Young Scientists Journal Issue 17 - Royal Society Special

Celebrating 350 years of scientific publishing ROYAL SOCIETY SPECIAL ISSUE

YOUNG SCIENTISTS A Future for Green Plastics?

Interview with Martin Rees, Astronomer Royal How Does School Affect Your Brain Waves?

Experimenting With Low Temperature Plasma Algae! The Answer To Our Food, Pharmaceutical and Energy Needs?

Do Sports Drinks Really Work?

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Editorial I

n our last issue, Issue 16, we announced our partnership with the Royal Society. Now only a few months later, we are very pleased to present our first ever special issue which includes research done by schools sponsored by Royal Society Partnership Grants as well as an interview with Former President of the Royal Society, Martin Rees.

Although this research has been primarily carried out by secondary school children, we have three incredible pieces by primary school children which can be accessed by following the link or QR code in the journal. These include a video presented by the children themselves about earthquakes a, a presentation on making paints from plants and an experiment using a pendulum to kick tennis balls at a target. We are very proud of the fact that along with the Royal Society we are encouraging and helping these children to develop both the skills needed for the future and more importantly, a love of science.

Other than these, this issue sees a large variety of topics from all three main branches of science: physics, chemistry and biology. These range from Lockerbie Academy who looked at how car crashes are analysed and investigated to Redland Green School who used a Raspberry Pi computer to make a weather balloon, to a new selection of science in the news edited by Rachel Hyde. Many of these projects are still ‘work-in-progress’. We look forward to hearing how they shape up and will report back in a future issue.

In our modern world when so much plastic is thrown away, from milk bottles to empty take away cartons, it is very important to think about what will happen to them in the long term. Prior Park College has been doing this in their article, which compares the degradation of two different plastics. It is also very important to know what is in the products you use and so Dornoch Academy has been looking at the chemical makeup of shampoos and the essential oils contained within them using different chemical techniques.

Loreto College investigated plasma physics and its applications before running an experiment to find the ionisation energy of argon. Bordesley Green School set out to detect cosmic rays using a scintillation detector they had made as they were particularly interested in the effect of the atmosphere on cosmic rays and whether they could be related to lightning strikes.

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Finally we have an array of biologically orientated articles. The first is an article about an on-going research project at Sir Roger Manwood’s School into algae. They argue that algae may be a significant contributor in helping to combat the world’s approaching food and fuel shortages and so they are searching for the optimum growth conditions to help accelerate this process.

We then have two articles about sport, both by Brompton Academy. The first investigates the effects of stretching and in particular which kind of stretching is better for you whereas the second compares different hydrating drinks and their effect on performance.

La Sainte Union looks at the problems facing Britain’s native horse chestnut trees and whether anything can be done to save them, Boroughbridge High School looks at the practicalities and effectiveness of using essential oils as antimicrobial agents and Liverpool Life Sciences UTC looks at introducing the Darkling beetle into schools as an example of omic science. Finally, The Misbourne investigates something that preys on every students mind – what does school actually do to your brain and how does it change We hope you enjoy reading Issue 17 and will check out our website - ysjournal.com - for new articles, written by students from all over the world, published week by week. If you are interested in writing and publishing your own article or research, please visit our website or if you want to get involved with running the journal in any way, contact jointheteam@ ysjournal.com. For any other questions email editor@ ysjournal.com. We invite all our readers to join us at our second conference in Canterbury, UK, on the 14th of October 2015 with speakers, workshops, discussions and poster presentations, check ysjournal.com for updates.

Ed Vinson Chief Editor

Ed is a year 13 student at The King’s School, Canterbury, hoping to read Medicine at university.

If you are interested in applying for a Partnership Grant for your school, take a look at the Royal Society website (royalsociety.org/partnership) or contact the Education Outreach Team on education@royalsociety.org

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Foreword I

n this 350th anniversary year of scientific publishing, which began with the first issue of Philosophical Transactions in 1665, we can reflect on the huge impact the invention of the scientific journal has had on the way science is done.

Before the advent of the journal, scientific ideas were closely guarded by their originators, who often only communicated them – if they communicated them at all – in personal letters to their colleagues and competitors, which were all too easily lost. Afraid of being usurped by others, these early ‘natural philosophers’ (the term scientist didn’t come into use for another two centuries) would often use anagrams or coded messages in their letters to simultaneously keep their discovery a secret, and be able to claim priority once an idea became more established.

Secrecy is no foundation for building up a body of useful, reliable knowledge to be used for the benefit of humanity, however, and so the sharing of ideas was limited and progress was slow.

The Royal Society’s charter, granted by King Charles II in 1662, gave it the right to publish – a significant step when print was otherwise tightly controlled.

Set up by the Royal Society’s first secretary, Henry Oldenburg, Philosophical Transactions provided a means by which natural philosophers could gain credit for sharing their discoveries, with their names appearing in print alongside a date stamp that proved when the discovery was communicated. The decision of what would make it into the journal rested not only with Oldenburg, but also with the Council of the Royal Society, who were allowed to revise the tract, and so provide a framework for what we now call peer review to eventually fully develop. This condition established that the best judges of what counted as good science were other scientists.

Because the journal was published monthly, it was a quicker way of sharing the latest scientific ideas than a book, in addition to being cheaper to produce and

buy. The journal also allowed significant standalone ideas, which on their own might not be substantial enough for an entire book, to be shared, framing scientific discovery as an ongoing process rather than a finished body of knowledge. Ideas were, for the first time, made accessible for others to scrutinise, challenge and improve upon.

Scientific publishing has therefore been crucial for the progress of science, and so it is fitting that in this significant anniversary year we are working with Young Scientists Journal to publish the findings of scientific projects funded by our Partnership Grants scheme, which funds science, technology, engineering and mathematics projects in schools around the country with grants of up to £3000. Since 2000, the scheme has awarded £1.3 million to 770 schools and colleges, allowing young scientists the opportunity to work on their own investigative project with the help of a scientist or engineer. In this special issue of Young Scientists Journal, we present 15 papers by school groups whose projects were funded by our Partnerships Grants Scheme – all of which have undergone rigorous peer review by other young scientists.

The advent of the web just over a quarter of a century ago, and the first online journals a few years after that, has brought about some significant changes to scientific publishing, including open access, and changes to how data can be accessed and linked to. Fundamentally, however, the tens of thousands of journals that are published today all operate on the same principles established 350 years ago. I hope that the original research presented in this issue will provide the foundations for further projects that extend the work outlined here, both in the schools that undertook the projects originally, as well as others that have their own ideas about how those findings.

Sir Paul Nurse President of The Royal Society

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Contents Page No.

Title

2

Editorial

3

Foreword by Sir Paul Nurse

6

8

News

12

Car Crash Physics

14

Experimenting with Low Temperature Plasma

18

Younger Scientists Journal - Work by Primary Schools

20

A Raspberry Pi Weather Balloon

25

How Does School Affect Your Brain Waves?

A Future for Green Plastics?

27 Algae! The Answer to Our Food, Pharmaceutical and

Energy Needs?

30

The Enigma of Cosmic Rays

34

Interview with Lord Rees

36

How Does Stretching Help Us Do Sport?

38

Smells Like Teen Shampoo

43

Essential Oils, the Answer to Antibiotic Resistance?

46

Do Sports Drinks Really Work?

49

Philosophical Transactions: a Historical Perspective

53

What Ails Our Horse Chestnut Trees and How Can We Save Them?

62 The Darkling Beetle for Exploring “–omic” Science.

On the Cover

Plate 2 from the paper “An Account of Morne Garou, a Mountain in the Island of St. Vincent, with a Description of the Volcano on Its Summit. In a Letter from Mr. James Anderson, Surgeon, to Mr. Forsyth, His Majesty's Gardener at Kensington...”, Philosophical Transactions of the Royal Society, vol.75 (1785), pp.16-31.

The schematic painting shows the circumference of the crater, two lakes of water within it and a central cone issuing smoke. Also including the forested slopes of the mountain with some hurricane-destroyed trees.

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27

62

38

53

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News I Biology & Chemistry Genes from the woolly mammoth have successfully been inserted into the genome of an elephant by scientists at Harvard University. They disappeared from the Northern Hemisphere 10,000 years ago, but many of the specimens have been well-preserved due to the layer of permafrost protecting them from decomposition and being eaten by predators. Since DNA degrades over time, not enough mammoth DNA has yet been found to attempt cloning experiments.

[DISCOVERY]

This year, the first ever attempt to transplant a human head will be revealed. The idea, proposed by Canavero of the Turin Advanced Neuromodulation Group, aims to extend the lives of people whose organs are plagued with cancer. A major obstacle, the fusion of the spinal cord, could be overcome in time for surgery to begin in 2017. The patient, Canavero suggests, would be able to speak with the same voice, move their face and walk within a year.

[SKY]

Three men are able to control prosthetic hands with their minds, after their own were amputated due to severe nerve damage. The operation resulted in all three men bring able to pour water into a cup, pick up a ball and do up buttons.

Having sustained damage to the brachial plexus – the network of nerves running from the spine to the hand - the new ‘bionic’ hands improved their score on a standard test from 9 to 65 out of 100.

[BBC]

Children with three biological parents are now a possibility in the UK after the vote to legalise the use of donor mitochondrial DNA for IVF conceptions by the House of Commons.

Mothers with certain genetic conditions will be able to have children that share the majority of her genes, without passing the faulty genes on. The technology has received some strong ethical opposition, despite the fact that children born using such methods face no health problems.

[BBC]

Chimpanzees can learn additional languages; a new study shows. A team lead by Katie Slocombe recorded vocalisations of the word “apple” by a group of chimps from the Netherlands before and 3 years after moving to Edinburgh Zoo. The findings showed that the peak frequencies of the Dutch chimps’ calls fell from 932 to 708 hertz, which was very similar to the frequency of that of the Scottish ape, suggesting that they learned the local language.

[BBC]

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News I Astronomy & Physics The most complete solar eclipse for more than 15 years in Britain occurred in March, as the Moon passed directly between the Sun and the Earth. Percentage coverage varied from 98% in Northern Scotland to 85% in London. The alignment of the Sun, Earth and Moon is very rare due to the varying distances between them caused by the elliptical orbits of the Earth and Moon and their titled planes of rotation. The next total eclipse in Britain will be in 2090.

[NATIONAL GEOGRAPHIC]

Russian ice explorers have finally reached a lake buried underneath 4 km of Antarctic ice, having been isolated from the surface for 15 million years. Due to such a long period of isolation, Lake Vostok may be home to unseen life forms.

A team claimed in 2012 that water samples they obtained from the lake contained DNA dissimilar to known bacteria.

However, their results were negligible due to contamination of their sample with drilling fluid.

[ROYAL SOCIETY]

Light can form a Möbius strip - a surface with one side and edge. They are visualised by the description of twisting a strip of paper and sticking its ends together. Isaac Freund proposed that the polarisation of light, which describes the plane its which its electric field vibrates, could be twisted.

Peter Banzer and his team confirmed this by scattering polarised laser beams off a gold nanoparticle, resulting in a twisted polarisation pattern.

[PETER BANZER]

The Large Hadron Collider, which was restarted in March, has a new mission to find miniature black holes which would reveal the existence extra dimensions. The particle accelerator will smash protons together at double the energy that was used to find the Higgs boson. If holes are found at a particular energy, the theory of ‘rainbow gravity’, suggesting that the universe stretches infinitely back into time, with no Big Bang, could be proved true.

[CERN]

Two scars in the Earth’s crust, which are believed to be the remains of the largest meteorite crater ever found, have been discovered in Australia. They are thought to mark the place where a meteorite split in half before it collided with the ground over 300 million years ago, forming a crater of 400 kilometres in diameter. The impact would have sent thick dust clouds into the atmosphere possibly resulting in the extinction of many species.

[Australian Geographic]

Editor: Rachel Hyde, Arnold KEQMS

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INVESTIGATION A Future for Green Plastics?

A Future for Green Plastics?

Abstract

Our project was to discover whether polylactide, a bioplastic material made from extracted corn starch, would degrade more easily than polystyrene when exposed to different chemical environments. The polystyrene samples all increased in mass and most of the polylactide samples decreased in mass. Our results showed that polystyrene doesn’t easily degrade, which confirms our hypothesis.

Introduction

P

olylactic acid (PLA) or polylactide is a biodegradable thermoplastic aliphatic polyester derived from renewable resources, such as corn starch (in the United States), tapioca roots, chips or starch (mostly in Asia), or sugar cane (in the rest of the world). In 2010, PLA had the second highest consumption volume of any bioplastic of the world1

Corn Starch Corn

Biodegradable

PLA cycle4

Lactic Acid

PLA Cup

We are a group of Year 6 students from Paragon Junior School, Bath and Year 7 and Year 8 pupils from Prior Park College. Our project was to discover whether polylactide, a material made from extracted corn starch, could be used as a ‘green’ alternative to polystyrene. To establish this, the degradation properties of polylactide and polystyrene were measured by exposing the material to different chemicals and measuring the resulting change in mass.

We carried out numerous tests using different substances: acid (to represent fruit juice), alkali (to represent soap and hand gel), warm pond water (to 8

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[AGRODAILY]

A Future for Green Plastics? INVESTIGATION

see if it dissolves or breaks down), room temperature pond water and soil (to see if it breaks down under the ground).

In all of our experiments we compared polylactide and polystyrene. As well as considering how well the two plastics degrade, there is the question of the availability of the raw materials used to make each. Oil is used to make plastics like polythene and, according to The Institution of Mechanical Engineers, at the rate it’s being used it will run out by 2055!2

Bioplastic film used to help grow crops3

Equipment used to expose polystyrene and polylactide to various substances.

Making polylactide

Polylactide production is not made from oil but begins with corn or sugar beet. This is taken to larger factories to be fermented and create lactic acid.

It then undergoes a number of different industrial processes to form polylactide resin. This resin is then manufactured into everyday products, such as food products. The hope is that this will then decay and decompose to give off water and carbon dioxide which can be used again by the corn and sugar beet in the process of photosynthesis. This would mean we still have plastics but they might have less impact on the environment.

Method

Equipment: Independent variables: tap water, salt water, warm pond water, room temperature pond water, acid, alkali, soil.

Steps: Heat up an equal amount (3.5g) of polylactide and polystyrene until they have both melted, ensuring that they never come into contact with each other.

Try to get them into the same shape – a disc.

Remove the plastics and place them into separate containers which are the same size, using tweezers to avoid contamination (when a person contaminates something they make it dirty). Check the masses of the plastic samples and log them in a table.

Pour 50cm3 of the chosen independent variable,

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INVESTIGATION A Future for Green Plastics?

starting with tap water, over the plastic. If the plastic does not float do not touch it. Store both plastic samples in the same location at the temperature.

Check the plastics once a week, by drying them on a paper towel, logging the masses and placing the plastics back in the same containers only emptied, then pour some fresh independent variable. After some period of time, a recommendation is 6 weeks, stop the experiment.

Repeat the whole experiment with a different independent variable and ensure everything else stays the same and measure your results accurately.

The other independent variables include: soil, pond water, acid, alkali, brine (salty water) and warm pond water (50oC). As shown in the images of the experiments.

Results

From the graph it is possible to see the all the results for polystyrene (orange bars) show an increase in mass whereas for most of the tests on polylactide (blue bars) there has been a decrease in mass, i.e. some degradation.

The greatest increase in mass for polystyrene occurred in salt water and it increased by 0.135g.

Tap water also showed a large increase in mass of 0.125g (our graph shows rounded data). The acidic conditions showed the smallest increase in mass and only increased by 0.015 g. Soil and alkali also caused a quite large increase in mass whilst pond water and warm pond water only showed a smaller increase in mass.

Graph

From the graph on polylactide it is possible to see that there were three conditions where we saw a decrease in mass. There conditions were tap water, warm pond water and salt water. Tap water caused a decrease in mass of 0.02g and warm pond water and salt water decreased by 0.01g. However, the other conditions all caused an increase in mass, with the greatest increase in mass in the acidic and alkaline conditions. Both of these increase by 0.05g. The pond water and soil increased by 0.02g

Discussion

Polylactide – The tap water decreased in mass the most. We wondered if there had been some erosion or dissolving of the plastic in this experiment, perhaps indicating a chemical reaction. To be sure of this we would need to conduct further experiments and a number of repeats.

Salt water and warm pond water also all decreased in mass and we think this is due to some form of chemical reaction as with the tap water. However, the other substances dissolved in the water might have slowed this down. Again, we would need to conduct further experiments.

The acids and alkali did not decrease the mass and so we wondered if pH might affect the reaction.

Soil and pond water increased in mass and we wondered if it might be to do with the presence of other particles. We cannot come to firm conclusions, however, because we only did one disc in each condition and therefore cannot identify anomalous results. We have not conducted the experiment for long enough and to get clear results we would need to do this for longer, maybe years, otherwise we

Graph depicting the increase in mass of polystyrene and polylactide after exposure to various substances over a fixed duration of time.

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A Future for Green Plastics? INVESTIGATION

won’t know if it is successful. We think this requires further research, however, as we think there are some strong results here.

• •

We would take care to ensure that none of the fragile samples dropped on the floor or the benches.

We would try to use one single set of scales so that any scale error is nullified and be sure to clear off anything that might have dropped things onto the scales.

During this investigation people used their hands rather than forceps so got oil and grease on the samples so next time we would use gloves throughout.

We would also try to ensure that the room temperature samples were kept at a constant temperature.

“Our investigation shows that polylactide would • break down more easily than polystyrene, which makes it good for the • environment, especially considering that the oil from which polystyrene Conclusion is made is running out.

However, manufacturers might Polystyrene – All of the results show an increase in mass. For the salt water, it may be that as the be reluctant to choose water evaporated it left salt particles in the plastic disc. With the tap water we are not sure why it has polylactide if it is less gained mass but one explanation may be that it durable.” wasn’t dried properly. The alkali increased in mass Evaluation

On reflection there are a number of things we could do which would help us to improve our investigation further. If we were to repeat it, we would make sure we did the following things: •

• • • •

We would be sure to arrange a time when we know we can meet every week at the same time with no gaps for school holidays or other activities.

We would make sure we tested the polylactide and polystyrene simultaneously and also repeat the test with at least 2 more polylactide discs.

We would try to think of a way to keep the samples covered in a similar way to the soil.

We would need to be consistent about which way up the samples were positioned each time.

We would ensure we were more careful about how we dry the samples making sure we dry them enough, but not too vigorously to break them.

and we are unsure why but we wonder if there was some absorption of the alkali. For the experiment with the soil, there were definitely pieces of soil left in the plastic disc. There was a smaller increase in pond water and warm water and acid, which might be because there were no particles which could stick to the plastic discs. This shows us that polystyrene doesn’t degrade so it confirming our initial ideas.

Our investigation shows that polylactide would break down more easily than polystyrene, which makes it good for the environment, especially considering that the oil from which polystyrene is made is running out. However, manufacturers might be reluctant to choose polylactide if it is less durable.

References

1. Polylactic acid. (n.d.). Retrieved from Wikipedia 2. Oil forecast 3. “Mulch Film made of PLA-Blend Bio-Flex” by F. Kesselring, FKuR Willich. Licensed under CC BY-SA 3.0 de via Wikimedia Commons 4. PLA cycle

Author Prior Park College & Paragon Junior School, Bath Year 6 Paragon and Year 7 and Year 8 Prior Park College students joined together under the careful supervision of Dr Buchard to take the opportunity to experience the exploration of the unknown properties of Green Plastics.

Authors: Amelia Bouchaud, Hamish Row, Finlay Gall, Louis Wright, Jack Kerrigan, Tom Lynch, Charlie Mullin, Harish Karthikeyan, Max Smith, Ava Graham, Florence Robertson, Findley Taylor supported by Miss Frances Haynes, Dr Kathryn Rix, Dr Buchard, Mrs Fiona Bromley and Mrs Laura Michelsen-Cooney ROYAL SOCIETY SPECIAL I ISSUE 17 I WWW.YSJOURNAL.COM

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INVESTIGATION Car Crash Physics

Car Crash Physics Abstract

Working with Police Scotland, Physics students from Lockerbie Academy took part in a simulated crash investigation, based on a real crash that occurred in the local area. We used our knowledge of kinematics and problem solving skills to determine the cause of the collision. To do this we took measurements of displacement and deceleration and calculated the initial velocity of the car. The investigation found that the driver was at least partly to blame for driving too fast, therefore emphasising the importance of staying within the speed limit.

Funding Statement

Royal Society Partnership Grant

Introduction

O

ur project involved investigating a car crash that took place in the area local to Lockerbie Academy. A pedestrian was hit by a car on a tranquil town road near the public house late at night12 . The road had a 30mph speed limit. The driver of the car fled the collision site and the pedestrian was sent to hospital, unconscious. Witnesses were present, but their recollections were divergent, which could be due to factors such as the stress of the incident and the way in which our brains reconstruct memories as they are recalled1. Due to this lack of reliable eyewitness testimony, the cause of the collision and who was to blame had to be discovered using physics3 .

Methods

The artificial crash site was set up in the Assembly Hall at Lockerbie Academy at a 1/3 scale, using toy dolls and miniature cars. Our initial hypothesis was that the pedestrian walked into the path of the car as a result of being intoxicated, leaving the car insufficient time to brake.

We used the following equation to calculate the velocity at which the car was travelling before the driver noticed the pedestrian, as well as the impact speed4 .

v2 = u2 + 2as

Equation 1: where v is final velocity (ms-1), u is initial velocity (ms-1), a is acceleration, or deceleration if negative, (ms-2) and s is displacement (m).

Skid marks

Skid marks are the result of friction between a tyre and the road. The friction produces heat, which causes the breaking of intermolecular structures 12

within the rubber, leaving a black mark of melted bitumen on the surface of the road4 . We measured the length of the skid mark produced in the artificial crash site and scaled it up. This value was taken to be the displacement of the car as it decelerated and was used in Equation 1.

The pedestrian’s body

We also studied the pedestrian’s body using the simulated crash scene. Small pieces of masking tape were used to show the collision points on the body as well as the corresponding points on the car. These were then compared to consider what sort of impact occurred and how the speed of the pedestrian compared to the speed of the car at impact.

Deceleration

In order to calculate the velocity of the car when it collided with the pedestrian, we needed an estimate of the car’s deceleration as it slid across the road.

When crash investigators are studying a crash, they perform a skid test, using the car in the collision or, if that is not possible, a car of the same model and load5 . The vehicle is driven on the same road, with the same weather conditions, and the brakes are applied to their full extent. The vehicle has an accelerometer fitted to show the crash investigators the deceleration value in ms-2. The test is performed twice and, if the two values are within 10% of each other, they use the lower value as this gives a lower speed, which favours the driver2 . (If they are not within 10% of each other, the investigators continue repeating the test until they find two values that are.)

Values from the actual crash scene were used in the calculations.

Impact

Another important calculation to be made was the car’s speed when it impacted the pedestrian. We used Equation 1 again, with a value for displacement taken from the distance between the centre of the front wheels where they came to rest and the point where the skid marks wavered marginally, showing where the impact took place.

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Car Crash Physics INVESTIGATION

Results

Skid marks Using the artificial crash scene and scaling up the result, we discovered that the car had skidded 17.28 m before hitting the pedestrian and then another 7.17 m before stopping, making the skid mark length, and thus the displacement, 24.45 m. One issue with this result is that skid marks only form when the wheels of the car lock, not necessarily when the brakes are applied.

The pedestrian’s body There were injuries on the pedestrian’s upper leg, abdomen, shoulder and on the side of the head.

These were all on the right-hand side of their body.

Corresponding marks were on the bumper, bonnet and windscreen of the car. The pedestrian was hit below the waist, meaning they were ‘run under’, meaning the car passed below their body. This means that the pedestrian’s initial velocity was the instantaneous velocity of the car at the point of impact.

Deceleration The deceleration values recorded during the skid test were -6.80 ms-2 and -7.01 ms-2. We substituted the former value into Equation 1 along with the other values already gained, in order to find the car’s initial velocity. Below is the list of values: u=? v = 0 ms-1 a = -6.80 ms-2 s = 24.45 m Using Equation 1: 0 = u² + (2 x -6.80 x 24.45) So u²= 332.52 and u = 18.23 ms-1 or 41 mph. This shows that the driver was at fault, as they were driving at 11 mph over the speed limit.

Impact The distance between the centre of the front wheels and the point where the skid marks wavered marginally was measured and scaled up to be 7.17 m. We used Equation 1 to calculate the velocity at impact, which was found to be 9.87 ms-1 or 22 mph. It was also calculated that if the car had been travelling at the speed limit of 30 mph, it would

Reconstruction of the crash scene.

have stopped a full 4 m away from the pedestrian, meaning they would not have been harmed.

Conclusion

The results of our investigation have disproven the hypothesis that the pedestrian was solely responsible for the collision, as it was shown that the driver was travelling above the speed limit and could have stopped sooner if they had not done so. As a result of their dangerous driving, the driver was given an 8 month jail sentence and banned from driving.

However, the investigation has also shown that rash decisions made while intoxicated can threaten your life. This project has demonstrated how physics can be used outside of the classroom, as well as how difficult it can be to solve the mysteries held within a collision site.

Acknowledgements

The authors would like to thank Inspector Neil Hewitson, Constable Alan Hope and their colleagues at Police Scotland, as well as their teacher Mrs J.A. Hargreaves, for their contributions this project. They would also like to thank the adult volunteers who attended the Royal Society Summer Exhibition with them.

References

1. Hewitson, N. (2015). Personal communication with Inspector Hewitson, Police Scotland.

2. Hope, A. (2015). Personal communication with Constable Allan Hope, Police Scotland.

3. Arkowitz, H. and Lilienfeld, S.O. (2009, January 8) “Why Science Tells Us Not to Rely on Eyewitness Accounts”, Scientific American Mind. Online.

4. Duncan, T. (1994). Advanced Physics Fourth Edition. John Murray, London. page 140 5. Clayton, A. (2009, July 12) “Collision Analysis: Professional Road Accident Investigation”, Online.

Author Lockerbie Academy, Dumfries and Galloway Physics students from S2 (13 years) to S5 (16 years) from Lockerbie and Moffat Academies experienced the Road Crash investigator event as part of their Physics and Health & Well Being courses. From these students a group was selected based on their completing a selection of tasks relating to the event. Written by Leelah Grant-McMillan and Laura Webster Other Authors: Heather Beattie, Shona Beattie, Robyn Burns, Connall Hannah, Rebekah Hargreaves, Tom Hargreaves, Rory Holden, Hannah Hyslop, Angus Johnstone, Megan Johnstone, Callum Kingstree, Erin Lowry, Holly McKie, Owen Muir and Alyth Ross.

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EXPERIMENT

Experimenting with Low Temperature Plasma

Experimenting with Low Temperature Plasma Abstract

This paper describes a low temperature plasma physics and visible spectroscopy experiment set up and run

by A level physics students at Loreto College. Results are presented from the measurement of the breakdown voltage for an argon plasma, successfully measured for a wide range of pressures. The minimum breakdown voltage from these results has been used to find an experimental value of ionisation energy for argon. In addition, the results from a visible spectroscopy system are also presented, using a fibre optic array coupled to a monochromator and microchannel. The first set of results from this study is shown as a plot of relative intensity as a function of wavelength.

Introduction

P

lasma is the most abundant form of matter1 and was first identified by Sir William Crookes in 18792 . The word ‘plasma’ was first applied to ionised gas by Dr. Irving Langmuir, an American physicist, in 19273 . Plasmas consist of a collection of free moving electrons and ions. Energy is required to remove electrons from atoms to create ions; this energy can come in various forms including thermal, electrical or light. If there is insufficient energy to sustain the plasma, the particles recombine into atoms to form a neutral gas. Plasmas can be accelerated, directed and confined using magnetic fields. This allows them to be controlled and applied to a wide range of practical uses including space propulsion, industrial plasma processing, nuclear fusion, positron storage in dusty plasmas, plasma arcs, torches, steel recycling and lighting. Plasmas usually exist at high temperatures as high energy is required to sustain them, but they can also exist at lower temperatures.

Low Temperature Plasma System

The direct current (DC) low temperature plasma system used for the study is an Edwards S150 sputter coater, comprising two conducting plates (electrodes) separated by 10 cm. A potential difference of up to 1.5 kV is applied across the plates in a relatively low pressure environment of argon gas of 0.15 Torr (Torr is a unit of pressure where 1 Torr ≈ 133.3 Pascals). The electrical potential difference between the plates is enough to break down and ionise the gas to form a plasma. A picture of the argon plasma used in this experiment is shown in figure 1. The characteristics of the plasma are controlled by four variables: potential difference, distance between the plates, the type of gas used and the gas pressure.

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Paschen Law Experiment

In 1889, Friedrich Paschen developed a law to describe the minimum breakdown voltage of a gas as a function of the electrode spacing, d, and the pressure of the gas, P. The breakdown voltage is the potential difference necessary for a gas to discharge and become plasma. The process in which this happens is called a Townsend discharge, named after John Sealy Townsend. The Townsend discharge is a gas ionization process whereby free electrons are accelerated by a strong electric field and cause an electric current to flow through a gas. This current is then continued by avalanche multiplication caused by the ionization of molecules by ion impact. In this avalanche, positive ions drift towards the cathode (the negative electrode), while free electrons drift towards the anode. If the electric field is strong enough, the free electrons gain enough energy to liberate further electrons when they next collide with other molecules. These free electrons then travel towards the anode and gain enough energy from the electric field to cause impact ionisation when the next collisions occurs, creating more electrons; and so on. This process is a chain reaction of electron

WWW.YSJOURNAL.COM I ISSUE 17 I ROYAL SOCIETY SPECIAL Figure 1: Photograph of the argon plasma used

in the project.

Experimenting with Low Temperature Plasma

production which depends on the free electrons gaining sufficient energy between collisions to keep the avalanche going.

By considering Townsend’s first coefficient, α (units of m-1), the breakdown voltage can be shown as a function of potential difference, V, using the following equation:

where T is the temperature of the gas (K), σ is the cross section of the ionelectron collision (m2), k is the Boltzmann constant (1.38 x 10-23 J K-1) and d is the probability of ionising a gas per unit length of path (m-1).

To keep the discharge going, free electrons must be created at the cathode’s surface. Otherwise, there will be no electrons for ionisation to occur. This is possible because the ions hitting the cathode release secondary electrons upon impact. The mean number of generated secondary electrons per ion, γ, is given by:

Method

γ is also known as Townsend’s second coefficient (it has no units).

The aim of the experiment was to discover the relationship between the breakdown voltage of argon as a function of pressure and distance between the cathode and anode. This was achieved by varying the pressure in the gas discharge chamber in the Edwards S150 Sputter Coater. Unfortunately, the distance between the electrodes in the chamber is fixed at 12.5cm ±2 mm, so the only pressure could be changed for the experiment. A voltmeter was connected in parallel to the electrodes, in order to record the potential difference across the discharge.

An analogue Pirani gauge was used to measure the argon gas pressure to within ±0.02 T. The pressure in the gas chamber was varied by altering the opening of the gas input valve. The breakdown voltage of the gas was measured by gradually increasing the voltage applied to the electrodes, to the plasma has been just visible in a dark room. The potential at which this occurred was recorded as the breakdown voltage to within an absolute error of ± 3V.

Results

The results from the experiments are shown by figures 2(a), (b) and (c) in which minimum breakdown potential difference has been plotted against argon gas pressure. For the first experiment, figure 2(a), thirteen results were recorded and the graph shows a Paschen curve trend, with many results recorded around 0.2 T to accurately locate the minimum point of the curve. This is considered to be at a voltage of

EXPERIMENT

138 V and a pressure of 0.17 ±0.02 T. For the second experiment, thirty results were recorded to provide a wider range of values. Once again, a large number of these were measured at around 0.2 T, and the minimum of the graph was located at 133 V and 0.19 ±0.02 T. For the third and final experiment, twenty results were recorded and this experiment locates the minimum of the curve at 137 V and 0.18 ± 0.02 T.

The average pressure for the minimum breakdown voltage from all three results is 0.18 T (24 Pa).

From this data, α is calculated to be 0.013 ± 0.001 m-1, using T = 295.15K (room temperature) and σ = 3.5×10-20m2(calculated by McDaniel)4 . γ is therefore calculated to be 6000 ± 600 using α and d (expressed to 2 s.f.). The ionisation energy for argon was therefore calculated to be (8.3 ± 0.8) x 10-17 J, by taking the average of the minimum breakdown voltages discovered from the experiments, which is 136 ± 14 V. This is a factor of 33 times larger than the published ionisation energy of an argon atom of 2.5 × 10–18 J; experimental or human error could be factors, so carrying out more trials would be advantageous.

Visible Spectroscopy System

Atomic emission spectroscopy helps to identify the intensity of light at different wavelengths produced by a plasma to determine the elements it contains.

This type of spectroscopy is most commonly performed with a spectrometer and detector. For this experiment, a combination of a monochromator, photodetector and oscilloscope has been used to scan the visible wavelengths of an argon plasma.

Optical fibres have been used to transmit the light emitted from the plasma to the entrance slit of the monochromator. Optical fibre cables work by the principle of total internal reflection. When light enters a less optically dense medium (lower refractive index) from an optically denser medium (high refractive index), the emergent ray is reflected from the point at which the two mediums meet when the incident angle is higher than the critical angle. The core of the optical fibre cable is often made out glass or plastic and has a refractive index higher than the cladding surrounding it. This means that the light travelling down the cable bounces off the side at the same angle each time, so it can travel further.

For optical fibre cables used over a relatively short range, the diameter of the core can be increased with negligible adverse effect on the quality of the light being transmitted due to the short distance of the transmission. In the experiment, initially 1mm optical fibres were used, but the light received and transmitted by the cables was not sufficiently intense. The 3mm diameter fibre optics were added to the 1mm fibre configuration, which vastly improved the light level received and transmitted by

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EXPERIMENT

Experimenting with Low Temperature Plasma

Figure 2a: Plot of minimum breakdown voltage against argon gas pressure.

Figure 2b: Plot of minimum breakdown voltage against argon gas pressure.

Figure 3: Entrance and exit slits, mirror and diffraction grating set up for a monochromator, illustrating the light ray paths

mirror (E) at the exit slit (F). Each wavelength of light is focused to a different position at the slit, and the wavelength which is transmitted through the slit (G) depends on the rotation angle of the diffraction grating. The monochromator used in this experiment has a microchannel plate coupled to the exit slit, which acts as a photodetector.

A microchannel plate is made out of many vacuum tubes called microchannels, which are spread across the microchannel plate in parallel with each other, as shown in figure 4. A potential difference of 1 kV is applied across the microchannel plate.

When the photons from the plasma arrives at the photodetector, the incident photons strike the photocathode material of the photomultiplier. Due to the photoelectric effect, electrons are liberated from the photocathode material. As the incident photon is absorbed by the electron which exists in an orbital around the atom of the photocathode material, the electron gains enough energy to be freed from the

Figure 2c: Plot of minimum breakdown voltage against argon gas pressure.

the cables to the monochromator and increased the signal output to the oscilloscope.

A monochromator is an optical device that transmits a mechanically selectable narrow band of wavelengths of light, chosen from a wide range of input wavelengths. The wavelength of the atomic spectral line gives the identity of the element, while the intensity of the emitted light is proportional to the number of atoms of the element. A diagram of a common Czerny Turner design monochromator set-up is shown in figure 3. Light (A) is focused onto an entrance slit (B) and is collimated with a curved mirror (C). The collimated beam (light rays are parallel) is diffracted from a rotatable grating (D) and the dispersed beam is re-focused by a second 16

Figure 4: Diagram to show the structure and electron gain process for a microchannel plate

atom. The number of primary electrons produced is dependent on the number of photons of light entering the photodetector, and is therefore determined by the intensity of the light exiting the monochromator.

The primary electrons produced are directed by a focusing electrode toward an electron multiplier, the microchannel plate, as shown by the schematic diagram of electron gain in figure 5.

When the primary electrons arrive at the microchannel (also known as a dynode), they are accelerated by the electric field applied across

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Experimenting with Low Temperature Plasma

the micro channel, directed towards the wall of the microchannel and collide with it. Due to the phenomenon of secondary electron emission6 , more electrons of reduced energy are produced.

These secondary electrons are also accelerated by the electric field further along the microchannel and more collisions occur with the wall, so the same process repeats with evermore increase in the number of electrons produced. The electrons produced are picked up by an anode which produces a current proportional to the number of photons

Figure 5: Schematic diagram of the microchannel plate electron gain process

initially entering the photomultiplier. This process of multiplying electrons makes it possible to detect very small electromagnetic signals, in the form of photons entering the photodetector initially.

The output signals from the photodetector for the different wavelength settings of the monochromator, are input into an oscilloscope allowing the relative intensities to be recorded. The initial set of results of relative intensity has been plotted as a function of wavelength and is shown in figure 6. The next step for this study will be to compare the characteristic peaks of the graph with published wavelengths to identify the chemical composition of the argon plasma and any impurities and contamination that may be present.

Summary

Results have been presented from an experimental study of plasma physics and visible spectroscopy for a low temperature argon plasma. The breakdown voltage for the argon plasma has been successfully measured for a wide range of pressures and repeated three times. The minimum breakdown

EXPERIMENT

Figure 6: A graph of relative intensity as a function of wavelength for the argon plasma used in this study.

voltage has been used to find an experimental value of the ionisation energy of argon, (8.3±0.8) x 1017 J per atom. This value compares well with the published value of 2.5 x10-18 J per atom, though further experiments could help to eliminate any sources of error.

A visible spectroscopy system has been set-up for the argon plasma using a fibre optic set-up coupled to the entrance slit of a monochromator.

The monochromator itself is connected to a microchannel plate which has been used to measure the relative intensities of the argon plasma. The first set of results from this study is shown as a plot of relative intensity as a function of wavelength.

The next step will be the identification of the chemical composition of the plasma and possible contaminants.

References

1. Gurnett, D.A. (2005) “Introduction to Plasma Physics: With Space and Laboratory Applications”, Cambridge, Cambridge University Press, pg. 2.

2. Crookes, W. (1879) “Radiant Matter”, Philadelphia, James W. Queen & Co. 3. Tonks, Lewi, and Irving Langmuir. “A general theory of the plasma of an arc.” Physical review 34.6 (1929): 876.

4. McDaniel, E. (1964). Collision Phenomena in Ionized Gases.

New York: Wiley & Sons.

5. Czerny, M., and A. F. Turner. “Über den astigmatismus bei spiegelspektrometern.” Zeitschrift für Physik 61.11-12 (1930): 792-797 6. Wiza, Joseph Ladislas. “Microchannel plate detectors.”

Nuclear Instruments and Methods 162.1 (1979): 587-601.

Author Loreto College, Manchester We are a group of students at Loreto College, we had tremendous fun with this project, and are inspired to carry on with STEM subjects at University.

Authors: Y Alhamwy, E AlShami, HB Qu, CE Rockson ROYAL SOCIETY SPECIAL I ISSUE 17 I WWW.YSJOURNAL.COM

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YOUNGER SCIENTISTS JOURNAL It’s never too early to get excited by Science, as the projects on this spread conducted by younger scientists at primary school testify. Just scan the QR codes with your smartphone or ysjournal.com/issue-17-primary to see their projects in more detail. If your school would like to do a similar project visit the Royal Society website (royalsociety.org/partnership) or email education@royalsociety.org

Nature’s Palette - Making Paint from Plants

St Godric’s RCVA Primary School Investigate whether natural materials (such as berries and seeds) could be used to make paints and dyes.

See the investigation by scanning the QR Code or going to: ysjournal.com/issue-17-primary 18

WWW.YSJOURNAL.COM I ISSUE 17 I ROYAL SOCIETY SPECIAL

Earthquakes: Small or Far Away?

Birdwell Primary School produce an informative dramatized video on Earthquakes

Watch the video by scanning the QR Code or going to: ysjournal.com/issue-17-primary

Pendulum Swing Experiment Wharton C of E Primary School experiment with a device to make kicking a ball more accurate.

View the Prezi by scanning the QR Code or going to: ysjournal.com/issue-17-primary

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PROJECT

A Raspberry Pi Weather Balloon

A Raspberry Pi Weather Balloon Abstract

The aim of this project is to collect environmental data and take photographs from the upper atmosphere as an exercise in engineering and programming. The intention is to fly a helium-filled weather balloon up to a height of 37,000 metres, suspending a capsule of sensors powered by a Raspberry Pi microprocessor. Flight path will be determined using GPS data taken at regular intervals, with a pressure meter to help determine altitude. Temperature will also be taken at the same intervals via another module. Finally, a camera module will be attached to take a time lapse of the ascent. All of the data will be saved to an SD card. A radio module will broadcast the GPS signal so it is possible to find it once it has completed its ascent and fallen back to the ground. The capsule will consist of a high density closed cell foam box to protect the Raspberry Pi and sensors from damage during the fall.

Funding Statement

Royal Society Partnership Grant

Introduction

T

he aim of this project is to release a microprocessor-powered data-recording capsule into the upper atmosphere, attached to a helium-filled weather balloon. This launch has not yet taken place, but much work has been done on the capsule. As the team had experience with using a small single-board Raspberry Pi computer (also referred to as Pi), this was used as the microprocessor. Temperature, air pressure and the GPS data will be recorded at regular intervals during the ascent using sensors wired to the Raspberry Pi, and the data broadcast to the ground via a radio module. This will also allow the calculation of the balloon’s altitude and its location as it returns to Earth. A small camera is also fixed to the capsule to record the flight. Preliminary research into similar projects indicated that the balloon would reach an approximate height of 37 km, at which point the balloon should burst, releasing the capsule.

The Raspberry Pi’s descent will be controlled by a parachute and the impact of landing lessened by a shock-resistant casing of some kind.

Method

A standard helium-filled weather balloon will be used and the capsule containing the Pi and modules attached to it. The dimensions of the balloon will be determined based on the mass of the final load.

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Coding and Raspberry Pi

Since the Pi must conduct multiple tasks, the components of the capsule are split into modules, each of which could be developed on multiple Pis. This solves potential issues like wiring conflicts and makes bug fixing easier – minor coding or wiring modifications can cause lots of problems, but any work done on one set of modules will not affect the others. The grouping of the modules is based on which components are dependent on each other.

For example, the temperature and pressure sensors are configured using the same Pi, as data will be logged to the same text file. The temperature and pressure file will be completely independent from image files, so the camera can be part of a separate module. Setting up the workflow like this means that multiple people can code at once on separate Pis. All the scripts that are created this way will be collected together and run by a single master script, making debugging a lot easier. Each development Pi and its corresponding breadboard of components will be combined to a single 256MB Pi, to which a high data capacity SD card with all the scripts and master script on it will be inserted.

All of the functions and data collection from various sensors need to be programmed so the Pi can carry out the desired functions exactly. Python, a programming language that comes preinstalled on Raspbian (Raspberry Pi’s operating system), was chosen for the project, as it is relatively easy for less experienced programmers to pick up. As most Pi users also use Python, there are many tutorials and existing codes on the internet that are useful for this project.

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[vitaminoc.com]

A Raspberry Pi Weather Balloon

The first element the project tackles is recording the ambient environment of the capsule and storing this data in a text file, beginning with the connection of the physical sensors to the Pi so they could communicate. A Raspberry Pi has two rows of 13 General Purpose Input/Output (GPIO) pins that can be used to connect the Pi to anything that does not have a USB. Sensors must be attached to these.

Research into how the components should be attached is summarised in figure 1.

PROJECT

The BMP085 pressure sensor (Figure 2) is much more complex, consisting of its own small circuit board. However, it does have labelled pins which can be easily be connected to the right parts of the Pi. After accessing the right GPIO ports for each sensor and calling the right part of the output data, temperature and pressure, it is output to a single text file. The programme can also be looped and a time stamp added to each reading to aid interpretation.

The next challenge is integrating the GPS module (Figure 3) into the other sensors and writing the capsule’s latitude and longitude to the same text file.

The GPS module is another stand-alone component with comprehensive pre-installed software that outputs a range of data from location to velocity.

Figure 2: The BMP085 pressure sensor.

After connecting the GPS to the correct GPIO pins, the Adafruit website became very useful in helping to extract the latitude and longitude from the data the module provided. The data could then easily be inserted into the temperature and pressure text file.

A minor setback faced whilst trying to work with the GPS unit is that in order to test and troubleshoot the code, a GPS signal was required which was not

Figure 3: Adafruit ultimate GPS module with aerial. www.learn.adafruit.com always available within the school building.

There is also the possibility of using GPS to calculate altitude, though further testing and research would be needed to confirm if it would work above a certain altitude.

Figure 1: Diagram showing the pins on a on the Raspberry Pi and connections to the temperature sensor. The DS18B20 temperature sensor is a simple component, connected to the 3.3V, GND and 4th GPIO pin.

Casing

For the casing of the Raspberry Pi and the modules, high-density closed-cell foam will be used. There were concerns about the impact of low pressure on the foam and whether this would cause it to

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PROJECT

A Raspberry Pi Weather Balloon

Figure 5: Radiometrix NTX2 Transmitter Figure 4: Capsule (unfinished) with the battery pack and Pi in place. expand, possibly resulting in structural damage and an inability to hold all the components safely.

However, tests on the foam in a vacuum jar showed that the foam was not affected by the extremely low pressure in any way and retained its strength on repressurisation.

The Raspberry Pi and other components were measured to determine appropriate dimensions that would leave enough space for all the components.

The foam was cut using a scroll saw and will be finished with the belt sander to ensure straight edges. The casing can be seen in figure 4.

The casing will be finished at a later date after bringing all the different components together onto one Raspberry Pi. It will also be drop-tested with the small parachute. After this, any modifications for strength or fit, such as adding a space on the outside for the camera, will be added. This will be done later as all of the modules need to be brought together to determine how it will all fit, before foam inserts are added to ensure snug, gapless fit, so nothing can be damaged.

Data Transmission

The broadcast of data back down to Earth has been one of the biggest challenges. The NTX2 transmitter from Radiometrix (Figure 5) is small, light and, crucially, broadcasts on a frequency outside that of any radio station, removing the likelihood of encroaching on any regulations. Connecting the transmitter to the Pi was a straightforward procedure.

A laptop was used to receive and interpret the data rather than another Pi, as this would require much more processing power than available on a Pi, and there are no weight limits. This also allows the broadcast of the minimum amount of data from the Pi, as the data can be processed into graphs on the ground.

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Figure 6: YAESU Transceiver The difficulty was getting the Pi to use this transmitter to communicate with a laptop at a distance. The language Radioteletype (RTTY) was used for transmission, as it can convert data into basic binary that can be received and easily decoded into the relevant data. Thanks to the University of Southampton, who procured a transceiver that could receive the signal and output data to the computer (Figure 6), the laptop is able to receive at the frequency the Pi is broadcasting. Weeks of deliberation and research into which of the many output ports on the transceiver should be used, involving laptop chipsets and complex specifications, showed that an audio jack would work perfectly.

At this stage, the 434.075MHz radio frequency from the transmitter could be converted into an audio format, and outputted to a computer via the microphone port. To interpret the audio, Dl-FLdigi, a downloadable interpretation programme that even came with a high-altitude ballooning edition, allowed us to take this signal and translate it into readable numbers. The programme required a programming language, baud rate, frequency band, and the desired frequencies to be set. It would then convert any sound the laptop picked up to a string of letters and numbers.

The next and most challenging task so far is to

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A Raspberry Pi Weather Balloon

code the Pi to convert a text file to RTTY, then broadcast this encoded file’s 1s and 0s as high and low frequencies. To demonstrate control of the transmitter, with assistance from a technician, the GPIO pin, to which the transmitter was connected, was turned on and off. This involved a simple code consisting of a loop which set the pin to on (true), waited half a second, then set it to off (false), then waited before repeating. This would produce a regular oscillation between two frequencies, which could be received as two distinct pitches through the transceiver. However, work on how to encode and transmit the initial text file is still ongoing. It is a matter of finding the right code on the internet and adapting it to the needs of the project.

Camera

There will be a camera on the capsule which will be used to take photos at regular intervals of the ascent and descent. This will be Raspberry Pi’s own camera module (Figure 7), with a fixed focus and 5-megapixel sensor. The pictures will be used to create a time-lapse which will be corrected for

PROJECT

In Python the ‘for’ loop repeats a user-defined number of times. In the loop, the picamera.capture function was used, which was imported at the start of the script. The function being used takes a photo and then names it x.jpg in any chosen location, ‘x’ being the iteration number of the loop. This means that no pictures will be written over, and we are able to set location allowing multiple time lapses to be recorded during testing and be stored in separate folders. After the picamera.capture has completed the loop moves onto the time.sleep function which pauses the code for a set amount of time which can be controlled by changing the variable. Once time. sleep has completed the code the loop ends and starts again from the beginning until the code is told to stop or until the loop has reached the end.

The images taken by the camera that are stored on the SD card will be used to create a time lapse using Adobe Premiere Pro. They will then be stabilised and colour corrected using Adobe After Effects.

Power

The Raspberry Pi, for normal use, requires a DC power input via a standard micro USB. Whilst programming a wall socket adapter has been used, but unfortunately there are no wall sockets 30 kilometres up, so battery power is required. Rather than buying one of the increasingly popular USB battery chargers, a battery pack was designed and built (Figure 8), which uses a step down DC transformer to convert the 9 volts produced by 6 AA batteries to the 5 volts the Pi needs for a sufficient duration of time.

Figure 7: The Raspberry Pi camera

stabilisation and exposure in post-processing on the ground with a video editing suite.

The camera has been coded with a loop that will repeat for the number of photos wanted. Within the loop there is a command to take a photo, after which the programme waits for a set length of time. This will be the interval between photos.

The Pi camera came with its own set of commands which, after downloading, can be called in any script to take video and images. The python-picamera commands by Dave Jones were used as they best fitted this project’s needs. Raspberry Pis come with a camera slot attached to their circuit board, so connecting the camera consisted only of plugging it in.

Figure 8: Power pack, including transformer and batteries.

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PROJECT

A Raspberry Pi Weather Balloon

Discussion and Conclusion

This paper is far from a complete description of our high altitude balloon flight and its results, but more a summary of our endeavours up to this date, and how we intend to proceed.

The biggest issue and the main task that has slowed progression is the problem of getting the Pi to communicate with the laptop. With the ability to code and transmit in RTTY, the rest of the project can proceed. With all of the components assembled

Figure 9: The 256MB Raspberry Pi model A, with a heat sink mounted on the CPU.

and coded on individual Pis, the master code can. be assembled, and coded to run on start-up. This will go on a large 64MB SD card, and then in a super-lightweight Raspberry Pi model A (Figure 9), which has less RAM but also fewer unnecessary sockets such as the Ethernet port the other models have. The challenge then will be integrating the wiring for the various sensors, resistors and other components onto a single tiny breadboard (Figure 10), and soldering each join in place. This will involve some code editing as different components need to use the same GPIO pins, but should not be too difficult. A spreadsheet on the ground will also be necessary to process the received data and output graphs, including changes in pressure, temperature and speed. While the GPS data will give a rough idea of altitude, the pressure sensor will provide much more accurate data, but raw pressure data must be converted into an equivalent altitude. The current setup is pictured in Figure 11.

The aim is to launch from Exmoor summer 2015 once the weather becomes more appropriate for a balloon launch. The capsule and the modules within it will be tested rigorously beforehand to ensure there is no sudden malfunction at any point.

Resources

Figure 10: Raspberry Pi breadboard.

• • • • • •

Barometer from Adafruit GPS from Adafruit Camera from Raspberry Pi Radio module from Radiometrix Radio transceiver from Yaesu Temperature module from Dallas Semiconductor

Glossary • • • •

Figure 11: Temperature, pressure and GPS sensors on a breadboard connected to a Raspberry Pi B.

Baud rate: a measure of how many times per second a signal changes (or could change).

Breadboard: a board of holes that are connected underneath in rows, allowing pins to be inserted in columns to connect to each other.

Import: tells the code to use a certain library of commands which can be called later in the programme.

RTTY: RadioTeleTYpe, a communications system.

Acknowledgements

Mr Tom Wilson, Redland Green School, and Professor Philip Wilson, University of Southampton.

Author Redland Green School, Bristol We are a tenacious group of comprehensive school students at Redland Green School Bristol aged 12-17, who have spent 3 years working on an after school STEM club project to send a balloon to the edge of Space. Authors: James Hinschelwood, Alex Sidiqui, Issaac Wales, Max Williamson 24

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How Does School Affect Your Brain Waves?

EXPERIMENT

How Does School Affect your Brain Waves?

[TELEGRAPH]

Abstract

We carried out an experiment testing our brain waves to see how relaxed we were during different activities in school, using the Myndplay App. We hypothesised that activities such as constructing a star in Design & Technology (D&T) and drawing would be “resting” activities, whereas activities requiring more cognitive function, like typing and gaming, would be “non resting” activities. Our results showed that some activities such as attending the theatre, typing, and weaving are relaxing for us, but activities such as making things and playing percussion are not. he aim of our experiment was to how our Funding Statement brains respond to certain activities. In Royal Society Partnership Grant particular, we wanted to study brain waves and how they change according to what activity you are Materials and Methods doing. We used the following equipment to do this: • Neurosky Mindwave mobile headsets bought from Myndplay (see figure 1) • iPhones/iPads with Myndplay App • Myndplayer Pro Software

T

The following activities, which involved many different departments of our school, were investigated: • cutting a star with a saw in D&T (referred to as “constructing the star”) • drawing some sweets in art • playing percussion in music (call and response activity) • observing a light show in music • watching a play in drama (“Bugsy Malone”) • typing up a story (“Goldilocks and the Three Bears”) • making a rug out of threads in textiles • playing a computer game (Pacman) • solving a maths problem

Figure 1: The Neurosky Mindwave mobile headset

To start, we uploaded the Myndplay App onto our iPads and iPhones. This is an app where you can observe and record your brain waves1. We were interested mainly in mid Gamma, high Alpha, and high Beta waves, as these are active when we are conscious2 (see figure 2 for an image of different types of brain waves). To record data during the

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EXPERIMENT

How Does School Affect Your Brain Waves?

activity, we had to pair our NeuroSky headset by Bluetooth to our iPhone or iPad. We then had to carry out breathing exercises to calm ourselves down. Thereafter, we recorded our brain wave

Figure 2: different types of brain waves [SSRC] patterns whilst carrying out the respective activity in approximately five one minute recordings (longer recordings tended to crash Myndplay). All data was then saved and analysed using the Myndplayer Pro Software. The data was converted to an Excel file so that a graph could be generated from the data. Users also use Python, there are many tutorials and existing codes on the internet that are useful for this project.

We only looked at the middle 20 seconds because the first 20 seconds are based on starting the recording, and the last 20 seconds are on based on stopping the recording. So the middle section contained the data we were interested in, and we found out the mean of the three waves, and plotted a bar chart for each 20 second set of data and recorded the majority wave.

Results

195 graphs were analysed and the results showed that the following activities are: • “Resting” (α wave) activities: watching drama, typing, problem solving in maths, watching a light show and weaving • “Non resting” (β wave) activities: playing percussion and constructing the star

•

“Problem solving” (γ wave) activities: drawing and gaming

Discussion

Before we started the project we thought that activities such as constructing the star and drawing would be “resting” activities, and activities requiring more cognitive function, like typing and gaming, would be “non resting” activities. Looking back at the experiment there were factors that could affect our results, such as interruptions from people entering and leaving the room whilst we were collecting data.

Texting, photographs being taken, weather (data collection occurred throughout the year), incidents in lessons prior to data collection, mood and talking with others could have affected our results as well.

We also had to start and end the data collection on our iPhones and iPads ourselves, and this would have affected the results. Ideally, it would have been better if we could have had another person starting and finishing the data collection. Other improvements would be to have minimum of 5 students to carry out each activity and have a controlled environment to carry out data collection, without disturbances.

What the results mean for us as students is that some activities like attending the theatre, typing, and weaving are relaxing for us, but activities like making things and playing percussion are not. This kind of data can be useful when you want to get yourself to a certain state, or help teachers when they want a calm atmosphere, or a busy environment, where students are engaged in higher learning tasks like maths problems. Teachers can manipulate the learning atmosphere in the classroom by altering the type of activity given to their students.

Acknowledgements

Dr. Pascal Durrenberger, Ms. Anita Kapila, Mr. Danny Noctor, Mrs. Maxine Nicholls, Miss. Grace Curtis, Mr. Neil Maguire, Mr. Tom Stratford, Mr.David Lewis, Mrs Robyn Jeffries, Ms. Cathy Hillier, Mrs Jan Russell, and Myndplay

References

1. Myndplay app (2015). “Myndplay Explained”, Online.

2. Brogaard, B. (2012) “Brain Waves as Neural Correlates of Consciousness”, Psychology Today, Online.

Author The Misbourne School, Buckinghamshire The Misbourne is a close-knit family community school in Great Missenden, Buckinghamshire. We found this project fascinating; we’ll never think of thinking in the same way again.

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The Answer to Our Food, Pharmaceutical and Energy needs? INVESTIGATION

Algae! The Answer to Our Food, Pharmaceutical and Energy Needs?

Abstract

Our world is constantly searching for new energy sources and new mass food supplies due to the constant high demand and so a decrease in their supplies and the answer could be…algae! Algae have the potential to help solve some of these problems. In order to achieve this, however they must be produced at an accelerated rate, and we’re hoping to find out how. We will do this by finding the optimum growth conditions required by the algae and understanding some of their vital growth requirements. This includes the need for a symbiotic relationship with bacteria which may supply Vitamin B12 to the algae. Our experiments will measure the algal growth in different conditions so we can find if algae needs symbiotic conditions to grow fastest.

Funding Statement

Royal Society Partnership Grant

See our glossary below for explanations of the words in italics.

Introduction

Our experiment (still work-in-progress):

Algae are a potential source of fuel for the future as they can produce many natural oils and can become a rather useful renewable source to help replace natural oil, which is a non-renewable fuel2.

Method:

M

icro-algae (microscopic plants) are unicellular species that are quite unfamiliar to most people.1 Many readers will be unaware about an innovative plan that has the possibility to change our future and energy forever. We are a group of year 12 students taking part in a project in collaboration with AlgaeCytes – a biotechnology company based in Sandwich, Kent, UK. We aim to accelerate the production of high value products from algae by carrying out this investigation.

Algae could also produce active bio-ingredients and proteins for healthcare3. They are already being used as food throughout the world, and could become more popular in the western world, lowering demand and strain on our current food supplies. Currently algae are being used as bulking or gelling agents in the food industry by using algal strains, since they are capable of producing high levels of carbohydrates especially polysaccharides. The fact that algae can use phosphates and nitrates from recovered waste process water from food and beverage factories also make it very economical and environmentally friendly. It also means the factories can meet EU and USA legislation for water quality discharge. This all shows the huge future benefits for algae and so illustrates the benefits of our investigation.

Our hypothesis is that algae will grow at an optimum rate in symbiotic conditions. This means “helper bacteria” are needed for the algae to grow optimally because they may be providing B12 to the algae, a vitamin vital to growth. (Algae are unusual in their requirement of Vitamin B12 as higher plants do not require it at all.) Vitamin B12 is also known as cobalamin and is an organic micronutrient uniquely made by bacteria. The algae may be dependent for their metabolism for this.

Our aim is to grow four separate samples of algae each under different conditions in order to investigate the best conditions for growth. A centrifuge was used to separate the algae.

1. One will be washed three times to remove all bacteria and create the cleanest conditions to see how that will affect algal growth. It may show that algae actually need only a small amount of bacteria to grow.

2. The second will be washed once and spun in a centrifuge so that bacteria will still be present in this sample. We expect that this algal culture will grow well as the bacteria present may be providing Vitamin B12 to the algae.

3. The third sample of algae will be washed and spun three times to remove bacteria but Vitamin B12 will be added as a supplement. This is to see whether Vitamin B12 is the factor being supplied

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INVESTIGATION The Answer to Our food, Pharmaceutical and Energy needs?

Figure 2 (Below): Cobalamin4

Figure 1 (Above): Micro-algae4 by the bacteria and hence why it is growing so well and would provide an answer as to why algae would need bacteria to grow.

4. The fourth and final sample of bacteria will also be washed three times and antibiotics will be added to remove all bacteria present to give axenic conditions for the algae to grow – this is a culture where only one single species is present.

This will also give a clear indicator as to whether bacteria are needed.

Experiments on each flask will be repeated to increase the reliability of our results, and strict adherence to aseptic technique will reduce the risk of anomalous results.

To determine the growth of the algae we will measure the cell density every week for 8 weeks using a haemocytometer. This is a microscopic grid that provides an easy counting system. Using mathematical methods, the algal density will be determined and results will be displayed as a growth curve.

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INVESTIGATION

Figure 3: Haemocytometer5

Glossary

We will also monitor the presence of bacteria in the cultures at the beginning and end of the algal growth period. A sample from each culture will be serially diluted and each diluted sample will be spread on an agar plate. After incubation, this will allow us to count the number of colonies. As each colony originates from a single cell, the original number of viable bacteria in the original culture can be determined using mathematical methods.

• •

Summary:

Acknowledgements

With this project we hope to show that algae are dependent on a symbiotic relationship with bacteria to grow at an optimal rate and therefore cannot grow as quickly in an axenic environment. Furthermore we hope to show that it is Vitamin B12 that the bacteria are providing for the bacteria. Watch this space: we’ll report back to Young Scientists Journal!

• • • •

unicellular - a single-celled organism algal strain - a strain is a genetic variant or sub-type of a species symbiotic - a close and long-term relationship between two or more different organisms metabolism - life-sustaining chemical reactions within an organism centrifuge - lab equipment which spins samples at high speed causing less dense components to move to the centre aseptic - techniques conducted in sterile conditions

Dr Jackie Wilson, Sir Roger Manwood’s School. Dr John Dodd, AlgaeCytes Ltd.

References

1. Wikipedia 2. Scott, S. A.; Davey, M. P.; Dennis, J. S.; Horst, I.; Howe, C. J.; Lea-Smith, D. J.; Smith, A. G. (2010). “Biodiesel from algae: Challenges and prospects”. Current Opinion in Biotechnology 21 (3): 277–286 3. Tokuşoglu, O.; Uunal, M. K. (2003). “Biomass Nutrient Profiles of Three Microalgae: Spirulina platensis, Chlorella vulgaris, and Isochrisis galbana”. Journal of Food Science 68 (4): 1144 4. Cobalamin (possible chemical form of Vitamin B12)

Author Sir Roger Manwood’s School, Kent

The three authors are Genevieve Butt, Georgia Green and Lois Mitchell. They are all Year 12 students and are all studying A levels, including Biology, Chemistry and Maths or Physics. Genevieve and Georgia are interested in studying Natural Sciences and Lois has a particular interest in Environmental Science. They are part of a bigger group of fourteen Year 12 AS Biology students who have been working on the project. They started last November by practising some of the methods needed for the project and then began the actual project in January 2015.

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PROJECT

The Enigma of Cosmic Rays

The Enigma of Cosmic Rays

[geek.com]

Abstract

The purpose of this project is to find out more about how cosmic rays are affected by the Earth’s atmosphere, if cosmic rays are related to lightning strikes and where they originate from. To test our hypotheses on the behaviour of cosmic rays, we constructed and tested a detector at our school, to be used for collecting data on cosmic rays. This information will be analysed and used by scientists all over the world to aid their research. In years to come, future students will be able to use the scintillator to test other hypotheses and contribute to the scientific community. This article will describe our current progress on constructing the detector.

Funding Statement Introduction

To investigate the provenance of ultra-high energy cosmic rays: where do cosmic rays come from?

Possible sources are the Sun and supernovae explosions in the Milky Way, but the most energetic cosmic rays probably come from extra-galactic sources2. Therefore, the question to investigate is: do showers of cosmic rays point to known objects in the sky map?

To investigate whether there is a correlation between the atmospheric weather conditions and the number of cosmic rays that enter the Earth’s atmosphere.

Cosmic rays can penetrate the atmosphere and influence the electrical properties of the air, as theoretical physicist A.V. Gurevich theorized for lightning1. Therefore, the question to investigate is: can cosmic rays be related to lightning strikes?

HiSPARC is an international, hands-on, physics research experiment which allows students to participate in actual European research collaboration3. It was created 10 years ago and there are currently around 90 detector stations in the Netherlands, along with many other active detectors in Denmark, Vietnam, Kenya and other countries around the world. The fact that similar detectors to ours are dotted all over the world will give us insight into how weather and climate relate to cosmic rays.

The research and investigation of cosmic rays is

Royal Society Partnership Grant

The purpose of this project is to find out more about how cosmic rays are affected by the Earth’s atmosphere, if cosmic rays are related to lightning strikes and where they originate from. Our objectives are:

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The Enigma of Cosmic Rays

fairly new, which means our findings and work could lead to pioneering discoveries. It is a rare opportunity for us to work with professionals and hi-tech equipment, and has opened our eyes to the world of particle physics.

Little is known in depth about the nature and origin of cosmic rays. As they are charged particles, the interstellar magnetic fields cause their trajectories to change numerous times4. Cosmic ray detectors allow us to measure the energy these particles have, expanding our scientific understanding of them. Any data that we collect will contribute to the scientific community and our understanding of cosmic rays, providing us with ground-breaking information and widening our knowledge of the universe. We aspire to gain a better understanding of cosmic rays and their behaviour in multiple scenarios as well as answering our specific questions about them.

Background

Prior to starting this project, we were unaware of the nature of cosmic rays, so we carried out research through various means, primarily the internet, to find secondary data and research to aid us. We also asked the professionals working with us about cosmic rays, because they had invaluable past experience with HiSPARC. Most of the cosmic rays that reach the Earth are muons5. A muon is a type of lepton particle, similar to the electron but with a larger mass. The mass of a muon is about 200 times the mass of an electron.

Our detector is made of a slab of a substance which exhibits scintillation; namely, it luminesces when excited by ionising radiation. When a high energy particle passes through the scintillator slab, it gives energy to the atoms in the scintillator, also known as exciting them. The atoms release flashes of light (photons) and return to their ground state, the lowest energy state of an atom or other particle. The detector also includes a photomultiplier tube, which can detect faint amounts of light by taking advantage of the photoelectric effect6. This effect involves electrons being emitted from certain metals when light hits them. Within the photomultiplier tube, the photons hit the photocathode, a plate coated with a light sensitive material that has a low work function, meaning the material loses its electrons easily. These electrons are multiplied into a measurable electric current by a chain of electrodes, called dynodes, using potential difference. They travel along the tube, bouncing off the dynodes and producing more and more electrons7.

PROJECT

Construction of the Detector

To build the cosmic ray detector, we took the following steps.

1. First, we removed the clear plastic cover from the scintillator plates.

2. Using optical wipes and propanol, we cleaned both sides of the scintillators and all the edges.

We decided that propanol was the best solution to clean the scintillators with because it would evaporate quickly and leave almost no oil traces, as compared to alternative solvents.

3. We made sure that everyone wore gloves while handling the scintillators, as dust and fingerprints could decrease the quality of reflectivity or transmission. A good handling of the optics is essential to obtain results of high quality.

4. We wrapped the scintillators with aluminium foil to reflect light, so it would travel to the photodetector without being lost on the way. The aluminium was especially thick to reduce the chance of its tearing and leaving a strip of the scintillator bare.

5. To secure the foil in place, we used black insulation tape.

6. Next, we wrapped the scintillator in black pond liner to prevent light leaks, securing it with black insulation tape (Figure 1). We carried out this process on two rectangular and two triangular pieces of the scintillator, leaving the tops of the triangular pieces bare to be glued onto the rectangles.

7. We used optical glue to make sure that the photons pass through as much as possible without losses (Figure 2). After attaching a photomultiplier to the top of the scintillators, we tested for light leaks as we wanted to make sure that no light would escape or enter. We did this by a computer programme installed in our laptop, specifically created by HiSPARC (Figure 3). In order to create an environment similar to one the detector would be in while in use, we blacked out the room and tested it.

8. The final step is to attach a DAQ (Data Acquisition) system which will translate the signals we receive into a form that can be measured and recognised using computer software. The DAQ electronic box (Figure 4) also gives the necessary high voltage to the photomultipliers. After testing the detector, the final step is to place it into a special ski box (Figure 5) on the roof of our school, and begin research with the data.

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PROJECT

The Enigma of Cosmic Rays

Figure 1: Wrapping the scintillators in black pond liner.

Figure 2: Creating the optical glue.

Figure 3: Using the HiSPARC programme to test for light leaks.

Figure 4: The DAQ electronic box.

Figure 5: Ski box containing the scintillator.

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Testing the Detector

We had numerous complications with the optical glue. For instance, it would not set properly and the scintillator parts would come apart. To overcome this hurdle, we carefully scraped the glue off, so that the scintillator was not scratched, to create a smooth surface for the new optical glue to be applied. The first time we created the glue, air bubbles were present, so we tried using a vacuum subsequently – however, that approach was unsuccessful. A second attempt also proved unsuccessful. The third time we created the glue, we stirred very slowly and cautiously to prevent any air bubbles from entering.

This was successful and the scintillators were glued together, ready to use and collect data.

It is vital for us to carry out light leaking tests consistently; if there are light leaks in the scintillator, they could interfere with the cosmic rays to be detected. That is why we must double check and make any necessary repairs. No light must enter through the black plastic sheet over the aluminium; otherwise, the noise caused by the light leak would overcome the signal from cosmic rays. Voltage is important and must be optimised for the correct use of the photomultipliers. We will test a range of different voltages, keeping a record of the results. We will compare the data inside a room where all lights are off, and finally compare all results to check for light leaks within the scintillator. We want to find the conditions in which all signals from cosmic muons are detected efficiently with minimum noise. This is essential as this data will determine how many cosmic rays pass through the scintillator considering the variables that are provided. After this has been carried out, we will record the events in which muons pass through both our two scintillators at the same time, as this indicates that a shower has passed.

PROJECT

the chance to do research with it. It is imperative that we continuously gather the data from the scintillators. This will enable us to collect a sample large enough to find strong, reliable trends that support our hypothesis. All the processed data will be then sent to our collaborators in other parts of the world, like the Netherlands, where they will be collectively analysed using cutting-edge technology.

It is to determine whether there are any similar trends or even differences in all the data. A cause for the results can then hopefully be found. We are still in the process of establishing the best working conditions for the scintillators, but we will soon start our investigation on cosmic rays. We are very excited about doing real research with real scientists, and we hope to discover something new and significant!

This work has been made possible by funding from the Royal Society. We will present our work at the Summer Exhibition.

Acknowledgements

We would like to thank Cristina Lazzeroni and Angela from the University of Birmingham, as well as our Physics teachers, Abdul Salom and Ingrid Murray, for supporting us with this project.

References

1. A. V. Gurevich, G. M. Milikh, R. A. Roussel-Dupre, Phys. Lett. A 165, 463 (1992).

2. Preuss, P. (2012) “Where Do the Highest-Energy Cosmic Rays Come From? Probably Not from Gamma-Ray Bursts”, Berkeley Lab News Centre, Online.

3. The HiSPARC website 4. Mewalt, R.A. (1996) “Cosmic Rays”, Online.

5. Kliewer, S. (2006) “Muons”, The Berkeley Lab Cosmic Ray Telescope Project, Online.

6. ET Enterprises (2011) “Understanding Photomultipliers”, Online.

7. Nave, R. (2013), “The Photoelectric Effect”, HyperPhysics, Online.

Future Work

The detector now belongs to our school and has been installed on the roof. It will stay there for years to come, so that many students will have

Author Bordesley Green Girls’ School, Birmingham

The Bordesley Green Girls’ School HiSparc Group consists of twelve Sixth Form A Level students with a keen interest in particle physics.

Authors: Rahima Sultan, Sahra Abdirahman, Lamisah Salam, Moriom Begum, Moyrom Mir, Nadia Ahmed, Saeeda Begum, Saamiya Hassan, Rabia Gul, Yasmin Gul, Aishah Akhtar, Aminah Qasim

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INTERVIEW

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Interview with Lord Rees

Interview with Lord Rees

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Interview with Lord Rees

n the 10th of March YSJ Editorial Team Leader, Claire Nicholson, interviewed current Astronomer Royal, Martin Rees. Martin Rees is not only a Professor of Astronomy at Cambridge but also a member of the House of Lords. He is also a former President of the Royal Society.

Martin told YSJ that being President of the Royal Society was an incredibly demanding job, requiring him to talk to a wide variety of people, including scientists in many different fields, multiple government departments and contacts at the international counterparts of the Royal Society.

Part of the Royal Society’s role is to advise the government on issues involving science, sometimes giving immediate, urgent information, but at other times carrying out longer term studies on topics such as human population, geoengineering and health issues such as influenza. On the topic of the relationship between politics and science, Martin pointed out that politicians care more about the short term and local matters, whereas science often has to deal with plans that span decades and work on a national scale. He suggested that politics should perhaps be “less parochial in space and less constricted in time”.

Another question posed to Martin was why we should continue to study subjects such as astronomy when there are so many pressing concerns, such as food shortages and climate change, here on Earth.

He acknowledged that, although using science to solve the problems that the human race faces is essential, understanding our place in the universe is part of being human, and studying astronomy and astrophysics is one way to do this. For example, due to the knowledge gained by astrophysicists, we can now trace the atoms we’re made of back to stars, to understand how we came into being. Lord Rees also believes the discovery that everything is made of atoms is the greatest scientific breakthrough of all time, as it has enabled us to do “proper chemistry”, which is the most basic part of modern science and technology.

Martin is also the chair of the Longitude Prize committee, which is offering a £10 million prize to anyone who can solve the problem of antibiotic resistance. When asked about this topic, he said that new antibiotics must be developed if they are to continue helping people. However, there is a significant obstacle to overcome: companies are generally unwilling to develop new drugs without financial incentives. It is more lucrative to make drugs for people with lifelong illnesses, since they have no choice but to continue buying them, whereas drugs that will be used over a shorter period of time, such as antibiotics, will not make as much money.

INTERVIEW

In addition to creating new antibiotics, existing ones also need to be used a great deal less and no longer used at all on animals. Martin pointed out that “all science empowers human beings, and this can be used for good or for ill”, citing biotechnology as a developing field that could potentially help many people, but will also face ethical issues in the future.

The importance of science education was emphasised throughout the interview. Martin stated that “everyone in society should know about science because decisions on how science is used should always be made, not just by the scientists, but by everyone else”. He advised that teachers should recognise that they are not only teaching future scientists, but citizens who require a basic level of scientific knowledge to participate in society. Many children lose interest in science once they get to secondary school, so in order to stop this happening he suggested that children’s natural curiosity needs to be built upon more in school.

Martin believes that it is incredibly important for scientists to be able to communicate their research to the wider public; they should be able to write and speak, and present and argue their case well.

He said that this happens more now than when he was young, partly because email has become so widely used. In terms of advice for future science communicators, Martin said that is essential to know your own area of science well, but it is also important to have broad interests. You should also practise as much as possible by giving talks and getting involved however you can. His final piece of advice to any young person considering a career in science was this: “go into a subject where new things are happening – then you are not at a handicap compared to the old guys, because it’s new to everyone”.

Our thanks to Lord Rees for spending time with Young Scientists Journal.

Longitude Prize

In 1714, £20,000 was offered by the British government to anyone who could find longitude to within half a degree. 300 years later, in 2014, a new Longitude Prize, chosen by scientists and the public was launched. This is £10m to create/find a diagnostic test to detect bacterial infections, in order to prevent the overuse of antibiotics.

Claire Nicholson

Editorial Team Leader

Herts & Essex High School

Edited by Courtney Williams

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INVESTIGATION How Does Stretching Help Us Do Sport?

INVESTIGATION

How Does Stretching Help Us Do Sport?

Abstract

Over the past few years, long held beliefs regarding the value of pre-event stretching have been questioned, and increased attention has centred on the performance of higher-intensity movements during the warm-up period. The purpose of this investigation was to examine the acute effects of two different warm-up protocols on selected fitness measures in Brompton Academy students. Specifically, we compared the effects of two different warm up techniques using either static or dynamic stretching on the standing jump test, the agility t-test and a 20 metre sprint. We found that dynamic stretching was more effective, particularly for exercise involving power and strength.

Funding Statement

Royal Society Partnership Grant provided us with funding for sport science equipment to be used during the investigation and for future use.

Introduction

B

efore performing, training or competing, athletes must performing stretching exercises, as they help make sure the chance of injury is lower and prepare muscles for exercise1. There are two common stretching techniques, dynamic and static (shown in figure 1). Dynamic stretching is movement that stretches the muscles and keeps them moving at the same time, while static stretches are stretches that are held in a still position and include no movement2. Most athletes mix the two stretches up when warming up but the stretches have different effects so they might not be as useful and might even limit performance. We hypothesised that dynamic stretching would result in superior performance because, as it involves more movement, it must increase blood flow to the muscles.

Figure 1: examples of dynamic and static stretches 36

Method

To work out which set of stretches were more beneficial, we tested the effect of each with tests based on agility, power and speed. For agility we used the t-test which is a small course that is timed how long it takes for the participant to complete (see figure 2 for an example). For power we used the standing jump test, in which participants must jump from a standing position and the height they jump is measured. For speed, the amount of time participants took to sprint 20 metres was measured.

When planning our experiment we had to consider several different factors. We were aware that our participants were doing multiple tests and that this could affect our results. Because of this, we made sure that all participants completed exactly the same warm-ups and tests, in the same order. We also knew that there were many different things that could effect an individual’s performance, so to prevent us from getting completely anomalous results we asked each of our participants not to eat anything drastically different on each day of the sessions. We made sure to control every factor we possibly could and keep each test consistent, e.g. the same order every time, the type of warm-up and the facilities in which the tasks were completed.

For the static stretching session we made sure each participant did the stretches in the same order, held each stretch for 8-10 seconds and had the correct form. In the warm-up they had to do the adductor stretch, modified hurdles stretch, hip rotator stretch, bent-over toe raise, quadriceps stretch and a calf stretch. Similarly, for the dynamic stretching session, we checked they were doing the stretches correctly and that they

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INVESTIGATION

How Does Stretching Help Us Do Sport? INVESTIGATION and strength because they improve your ability in these areas more.

Limitations of the study Figure 2: A typical t-test

all did the same stretches in the same order. The stretches they had to complete were a high knee walk, straight leg march, hand walk, lunge walks, backwards lunge, high knee skip with arms, lateral shuffle, back pedal, by flicks and a high knee run.

When doing the warm-up two members of the team helped participants by telling them what to do and ensuring they were doing it correctly. Participants also walked for 5 minutes before each warm-up.

Results

For the standing jump test the mean height jumped was 187.50cm when the participants completed the static stretch warm-up and 199.75cm for the dynamic stretch warm-up. The dynamic value is 12.25cm more than the static, about 6%, which is a significant amount. This shows that dynamic stretching was more beneficial.

For the t-test the mean for static stretching was 13.48 seconds and for dynamic it was 12.96 seconds, meaning the difference between them was 0.52 seconds, or 4%, not as significant as the results for the standing jump test.

Finally, the results for the sprint test were a mean of 4.26 seconds for the static stretching and 4.14 seconds for the dynamic stretching. This was only a difference of 0.12 seconds, or 3%.

These results show that dynamic stretching was more beneficial for the participants when completing the tests. The standing jump test had the most significant result, and while the other two tests had smaller differences, they still showed that the dynamic stretching was more effective. The results could also suggest that dynamic stretching is best used when participating in sports that rely on power

There were some limitations to the study. One was that we had a small sample size, which reduced the strength of our statistical analysis. For more accurate results we would have to find a larger group of participants. Another limitation was that the order of the tests was the same for all participants and a different order may have suited some people better.

A final limitation was that a familiarisation trial was not completed, so the results could have been affected by the fact that some participants were doing these tests for the first time.

Conclusion

Our results showed that dynamic stretching significantly improved the participants’ results in the standing long jump, which shows that if you are competing in a sport where power is vital then it is better to have a warm-up consisting of dynamic stretches. The results for speed and agility showed that dynamic stretching had only a small effect, although it still resulted in some improvement in the both tests even if it was only by a small amount.

These results are in agreement with previous research that suggest that static stretching has the opposite effects on muscle strength and power3.

Acknowledgements

We would like to thank Mr. Denness, our teacher, for the opportunity to create our own sports science survey. We would also like to thank the University of Kent, who provided us with knowledge and understanding of sport science, as well as two sport ambassadors who guided us through the process.

Finally, thank you to the Royal Society for providing our Academy with funding so we could purchase sport science equipment.

References

1. AAOS (2012, January). “Warm Up, Cool Down and Be Flexible”, OrthoInfo, Online.

2. Appleton, B.D. (2012) “Types of Stretching”, Online.

3. Reynolds, G. (2013, April 3) “Reasons Not to Stretch”, New York Times Well Blog, Online.

Author Brompton Academy, Kent The group first met together at the Sport Science workshops which took place at the University of Kent. The project took place over five months in a series of phases.

Authors: Samantha Robinson, Grace Abbie Marriott and Prashida Rai. ROYAL SOCIETY SPECIAL I ISSUE 17 I WWW.YSJOURNAL.COM

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EXPERIMENT

Smells Like Teen Shampoo

Smells Like Teen Shampoo Abstract

Shampoos are an important part of our daily lives and they vary in terms of their smells and cleaning actions.

This project involved making shampoo using distillation to extract the key ingredient of a fragrance, essential oil. A variety of plants were used to extract the oils. To understand the chemical ingredients of the oils, two methods of analysis were performed: a process called thin layer chromatography, conducted in-class; and another called gas chromatography-mass spectrometry which was conducted by the Scotch Whisky Research Institute. Both tests revealed the chemicals present in the oils, the latter with a much higher accuracy. Once the shampoo was made, it was tested for pH, ability to clean and the all important ability to foam. To test if the shampoos could clean, horse hair and dolls’ hair were used. Afterwards, the shampoo work was presented in a Dragon’s Den style poster session to other students, teachers and a professional scientist who was as a partner in our project. Overall the shampoos all worked well and a greater understanding and enthusiasm for chemistry was gained.

Funding Statement

Royal Society Partnership Grant.

Introduction

T

his project studied the chemistry of the production of essential oils, the making of commercial shampoos, what chemicals are in shampoos and how to find out what chemicals are in shampoos. The school project at Dornoch Academy was performed in partnership with Whyte and Mackay, which allowed a professional scientist to give advice, look at our work and do chemical analysis that would otherwise be too expensive or difficult for our school to do. James Pryde is the chief chemist at Whyte and Mackay and has published a paper in which he analysed whisky taken to the South Pole by the explorer Ernest Shackleton and used chemical techniques such

gas chromatography, mass spectrometry and gas chromatography (GC) olfactrometry to identify the whisky and its components.1 Steam distillation was used to separate the essential oil from plants. This works by heating the mixture above the boiling point of the essential oil allowing the components to evaporate into the condenser.

The condenser permits the distillate to condense and run off into the collection flask.

Thin layer chromatography (TLC) was then carried out on the distillate and pure essential oils, to allow separation of the components of each essential oil and identification. TLC separates mixtures of substances into their component parts, allowing the distillate to be separated into the compounds it is composed of, and by comparison with the known pure compounds, the separate components can be identified. Different components separate due to them travelling different distances on the chromatography plate.

The emulsifier (in this case polysorbate-20) bonds with a polar water molecule on the left and the non-polar limonene from citrus oils on the right. This allows oil and water to mix and form a shampoo emulsion.

[HEADLINE]

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“Two important ingredients for shampoo: emulsifier to blend the oil and water; foaming agent to form the bubbles”

The distillate was then mixed along with the emulsifier (polysorbate-20) to allow the oils and the water to form an emulsion. The oils do not mix with water normally because the oils are non-polar and the water is polar. The emulsifier is able to bind to both the water and the oils due to it having a long non polar tail and a polar head, this forms a stable emulsion (figure 1).

Figure 2: Steam distillation setup by condensing the rising steam and to not char the plant matter. The sand is also a safety precaution to prevent the glass from shattering. The essential oil would gather in the collecting basin (figure 2)

Figure 1: Chemistry of emulsion formation Sodium laureth sulfate was the foaming agent we used; its purpose is to give the shampoo the bubbles that are seen when shampoo is used and also to give the impression that it is thoroughly cleaning.

Method

The main outline of the task was to extract essential oils from various materials and use them in the production of a shampoo. This involved blending and testing the shampoo to see how it performed and acted.

Preparation for distillation: Firstly the plants were chosen for the distillations to extract the essential oils. This included ginger, pine needles and citrus fruits such as lemon, orange and grapefruit. These were all obtained from local shops except pine needles, which came from a pine tree in the school. These plants needed to be cut or grated into smaller pieces to achieve a sufficient yield due to the increase in surface area. Water and a few antibumping granules were added to the plant matter.

These granules are made from aluminium oxide and help ensure smooth boiling.

Carrying out the distillation of plant matter: A heating plate combined with a sand basin provided a consistent and gentle heat. This meant that the plant matter’s extract could be collected efficiently

Forming the Shampoo: The essential oil extract (which provides the scent) was added to a 250cm3 beaker to which 5cm3 of water was added. The next chemical added was 30cm3 of sodium laureth sulphate (this is the foaming agent in shampoo) which works by encapsulating the dirt molecules by folding itself around it. It needed to be stirred in well so a magnetic stirrer was used for a consistent and thorough stir. Then 10cm3 of coco betaine was added and stirred in to the existing mixture; this was added to reduce irritation to the skin. 2cm3 of polysorbate-20 was added and stirred in. Polysorbate-20 is an emulsifier and which makes it useful in binding other components together. Coco Betaine is a surfactant, along with polysorbate-20, which bonds the water and oil molecules and reduces potential irritation by the sodium laureth sulfate. This is in the soap as it suspends the dirt molecules in the water to make it easier to wash away. Next the essential oils were added, only 0.5cm3 was needed due to the intensity of the fragrances. The mixture was then stirred to ensure total blending of all the components involved.

Thin Layer Chromatography: One drop of the essential oil dissolved in 1 ml hexane – along with two pure sample terpenes that were believed to be present in the essential oil – was spotted onto TLC paper and put it in a glass jar with 0.5 ml of solvent (Figure 3). After the solvent had run to 1cm from the top of the TLC paper, the TLC was removed and soaked in p-anisaldehyde solution or a permanganate dip. This procedure was a modified version of a published one.2 The TLC strip was then gently heated on a heating mantle to evaporate the solvent and reveal the terpenes present in the essential oil. Thin layer chromatography was

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Shampoo analysis Figure 3: Spotting essential oils onto Thin Layer Chromatography plates

Figure 4: Shampoo mixed with green ink. Note how there is no ink in the foam, a good sign.

attempted on the distillates but the yields of oils appeared to be too low for detection. Commercially bought essential oils were used for the thin layer chromatography analysis instead and the steam distillates were used for the shampoo.

The next test was the dirt test, or rather ink test as ink was used instead of dirt. This involved putting 2 drops of shampoo and one drop of ink into 10 ml of distilled water in a test tube then shaken vigorously and left to settle.

Results

This would produce foam. The ideal outcome is for there to be no ink/dirt in the foam, for it is meant to be in the water so that when you wash your hair it easily runs off your head. If it stayed in the foam, it could easily be redistributed into your hair as foam is harder to wash out than water (Figure 4). The final tests were an analysis of the foam produced upon vigorous shaking. 50 ml of 1% shampoo was put into a 250 ml graduated cylinder and shaken 10 times, the volume of the foam was then recorded as was the size of the bubbles, they could be either small, medium or large. A good shampoo should produce a foam volume of around twice the original volume of the shampoo, which our shampoo did3 .

The bubbles of the foam should also be small as it means the retention time of the foam will be longer.

At the same time as measuring the volume of foam the time of retention was also measured, a good shampoo will keep the same volume for around 5 minutes. Our shampoos managed to do this. To test if the shampoos could clean, horse hair and dolls’ hair were used.

Various fragrances of distillate were created, such as: lemon, lime and ginger. The distillations were a success, all groups produced a good product.

However the distillates by themselves proved not to be concentrated enough and so essential oils were bought commercially and also added in tiny quantities, such as ylang ylang and pine oil.

“red would mean it was acidic and so possibly irritant but would make the outer layer of hair lay flat and so make hair seem smoother”

There were several tests done to analyze the shampoo based on published methods3 , they are as follows: the pH test, which was done in order to see if the shampoo was safe enough for even the most sensitive of scalps, it was done using pH paper strips and universal indicator, red would mean it was acidic and so possibly irritant but would make the outer layer of hair lay flat and so make hair seem smoother, blue/purple would mean alkali and so possibly irritant but would make the outer layer of hair open up and swell making the hair frizzier. What was looked for was a nice shade of green meaning it was neutral and so would cause no harm and not be irritant in the slightest. All the shampoos produced green using the pH test.

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The results from the TLC experiments are summarised in the table: the table shows the terpenes present in each essential oil that were detected. Example TLCs are shown in figures 5 and 6.

The essential oil distillates were sent off for GC-MS analysis at the Scotch Whisky Research Institute.

Gas chromatography allows separation of the

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TLC of spearmint oil

Figure 5: This TLC result shows spearmint oil contains L-carvone but not eugenol.

TLC of orange oil Figure 6: The TLC shows that orange oil contains limonene and citral. The TLC plate was stained using a permanganate dip.

The results from the TLC experiments are shown here

Chemical Zingerone L-carvone L-limonene Citral

Essential oil Ginger X

Spearmint

Grapefruit

X X

X

Orange

X X

GC-MS data summary

Oil distillate Lemon Ginger Pine Grapefruit

Compounds detected by GC-MS Citral L-limonene X X X X X X

chemical components and mass spectrometry allows identification of the components. The results were sent back to the class to analyse the data, with the conclusions shown in the table.

Pinene and myrcene were expected to be in the pine oil but were not detected, although limonene was.

It is possible that heat damaged the pinene and myrcene but not the limonene.

Shampoo Project – Poster Presentation

Once the shampoo had been made, a presentation was done, showing how effective the shampoo was.

Myrcene

Pinene

Since there were three groups, it was decided that there would be a competition for best presentation and results. Posters were produced and explained to James Pryde from White and Mackay, Katie Elder (Science Curriculum Development Officer for the region) and pupils from the Advanced Higher chemistry class. The processes of steam distillation, TLC and the making of the shampoo were explained.

Demonstrations were then done to show that the shampoo lathered, that it removed dirt, and that it was suitable for use on skin. At the end of the presentation, questions were asked and satisfactorily answered. This project was very beneficial, as the information involved had to be learnt for the Higher

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Smells Like Teen Shampoo

chemical analysis was performed on the oils and shampoo was created and tested. Posters were presented to a professional scientist, GCMS data was analysed and next year the class will judge the shampoo projects of the pupils in the year below. The class were lucky enough to be visited by the two representatives of the Royal Society, who got to make shampoo with the class’s assistance. One thing that the class would have liked to have done is add colour to the shampoos, which may be tried next time with suitable dyes as the project continues to develop.

Acknowledgements

Figure 7: Horse hair was used to show the effectiveness of the shampoo.

Chemistry exam. It was easier to understand the theory behind the shampoo production because it was actually concocted. Making it a competition motivated the class to work to a high standard.

Presenting the shampoo to professionals meant that the information had to be thoroughly learnt, to avoid severe embarrassment!

Summary

This was an enjoyable project which seemed to make chemistry more relevant as we all use shampoos in our daily lives. Essential oils were extracted,

We would like to acknowledge the support of Dr James Pryde for agreeing to be a project partner and for technical advice, help with analysis, allowing visits to his lab and for judging the poster presentations. We would also like to thank John Connor of the Scotch Whisky Research Institute for analysing the steam distillates by GC-MS and concentrating our samples so they could be analysed. We would also like to thank Katie Elder, Laura Terry, Abbie Crew and Alex Wright for judging the poster session. Finally we would like to thank Dr Adrian Allan for giving us the opportunity to do the project and for help and support throughout.

References

1. Pryde, J., Conner, J., Jack, F., Lancaster, M., Meek, L., Owen, C., Paterson, R., Steele, G., Strang, F. and Woods, J. (2011), Sensory and Chemical Analysis of ‘Shackleton’s’ Mackinlay Scotch Whisky. Jnl Institute Brewing, 117: 156–165. doi: 10.1002/j.2050-0416.2011.tb00455.x 2. Isolation of Three Components from Spearmint Oil: An Exercise in Column and Thin-Layer Chromatography Don R. Davies and Todd M. Johnson Journal of Chemical Education 2007 84 (2), 318 3. SSERC shampoo tests

Author Dornoch Academy, Northern Scotland The authors are pupils aged 17-18 who are currently in their final year at Dornoch Academy having studied chemistry at Higher and Advanced Higher level. Most of them are going to study science at university after summer in areas such as medicine, chemistry, biochemistry, environmental sciences and life sciences. Authors: Rebekah Bryan, James Davidson, Sam Herbert, Zia Low, Andrew Mackay, Connie Mackinnon, Charlie Meeres, Brodie Pryde. Harry Richardson, Luis Stevens and Catriona Wilson 42

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Essential Oils, the Answer to Antibiotic Resistance? INVESTIGATION

Essential Oils, the Answer to Antibiotic Resistance?

Abstract

Essential oils have been known to inhibit bacterial growth so more and more companies are using them in their products as an alternative to ‘harsh chemicals’. We wanted to understand if, with increased usage, bacteria could become resistant to essential oils in a similar way to bacteria are becoming resistant to antibiotics. This was a useful way to understand the threat of antibiotic resistance. Would bacteria evolve resistance, or adapt?

These two possibilities may seem identical however if a bacterial cell were to evolve resistance it will forever have that resistance but if a bacterial cell adapts to the exposure of the essential oils, if you were to remove the bacterium from that environment the resistance would be reduced until it was non-existent. So what we are testing is if they adapt or evolve. We are doing this by putting a strain of E. coli in an environment where it can still grow but at a reduced rate because of the essential oils in its environment which may lead to the E. coli evolving or adapting.

Funding Statement

pathogens that cause many fatalities every year.

Royal Society Partnership Grant

The Project

Introduction: t Boroughbridge High School, our Year 10 gardeners have agreed to grow a medicinal herb garden with the plants chosen by students working on the Royal Society Partnership Grant project. These plants are also found in the Booke of Sovereign Medicines circa 15701, an electronic copy of which was given to the school by the Prior of Ampleforth Abbey. The plants will be used to teach pupils not only the many uses of the plants, but also the processes used to extract the oils. This will make the garden a valuable resource for the whole school and visiting primary school pupils.

Since the discovery of antibiotics, many believe that the pathogenic micro-organism threat to the population has been removed, with fatal infections and infectious diseases brought under control. Since synthetic drugs have shown such great success, there has been less research into drugs containing natural compounds. But now we are facing the rising problem of antibiotic resistance and must look at alternatives. New drugs are failing to keep up with the emergence of antibiotic resistant strains of

A

Summary of methods and results: Mr Inglis a teacher at Boroughbridge High School, started a weekly lunchtime microbiology club after a conversation with Professor Kevin Kerr, Head of Pathology at Harrogate Hospital. Prof. Kerr came into the school to discuss the looming antibiotic crisis with us and he suggested that studying essential oils might help us to understand antimicrobial properties. A number of plants produce aromatic oils which are described as the ‘essence’ of the plant; this is what gives lavender and rosemary their smell.

Essential oils are popular in fringe medicine and alternative remedies but it is difficult to obtain reliable references concerning their pharmacological merits.

The specialist equipment needed to carry out our experiments included Gilson multi-channel pipette and tips, microtitre trays and an autoclave.

Each member of our group suggested an oil to investigate, so we tested 5 different essential oils: • Lavender • Geranium • Cedar Wood • Rosemary • Thyme

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INVESTIGATION Essential Oils, the Answer to Antibiotic Resistance?

Rosemary at 1/16% dilution. These results allow us to conclude that some essential oils do inhibit bacterial growth, even at quite low concentrations; that they contain antimicrobial agents.

A multichannel pipette, such as the one we used in our experiments against 2 different types of bacterium: Escherichia coli (common gram-negative gut bacteria) and Staphylococcus epidermis (common gram-positive skin bacteria, also a close relative of MRSA).

Contacts with experts: During our research we visited Chris Bax of ‘Taste the Wild’ a local bush-craft expert who described some traditional plant based remedies. We also held a Skype video conference with a pharmaceutical company representative, who explained the different stages a new medicine must successfully pass through before it is cleared to be given to humans.

Throughout our investigations, we have learned how antibiotics are becoming increasingly ineffective in fighting infections because bacteria are developing resistance to current antibiotics. Despite this, there is a worrying decline in the number of new drugs in research, since there is increasingly little prospect of the pharmaceutical companies making a profit.

Our work attracted the attention of Professor Laura Piddock of the University of Birmingham and the We used disc-diffusion methods for a preliminary UK-led Antibiotic Action group. She campaigns study to see if the oils affected bacterial growth. tirelessly to urge Governments to take action over Cedar wood oil had no effect on the bacteria. We the problems caused by antibiotic resistance; our didn’t know if this was because teacher, Mr Inglis was awarded it had no antimicrobial effects or ‘Antibiotic Champion’ status by the because the oil molecules were so large they didn’t diffuse very well Editor’s note: Readers Antibiotic Action group and they offered to support our exhibit by through the agar. The size of the may be interested in providing a variety of resources. clear areas around the discs, the

the related Longitude

zone of inhibition, is affected by Prize, which gets a There was great excitement a number of variables including mention in the interview when we were also interviewed the size of the oil molecules. with Lord Rees in this by the BBC’s World Service and Essential oils comprise a complex issue. He chairs the featured in a Guardian Science mix of molecules all different Longitude Prize, which is Podcast. Lots of opportunities shapes and sizes, right down to offered for a significant were forthcoming, including an very small volatile compounds. invitation to the University of development in the As we don’t know which actual molecules affect bacterial growth, research into antibiotic Oxford to visit the laboratory where penicillin was developed. we decided to use a doubling resistance. dilution of nutrient broth since this will allow us to identify the concentration at which the oil molecules inhibit growth. The concentrations used Further work: were 4%, 2%, 1%, 0.5%, 0.25%, 0.125%, 0.0625%. A We have a list of plant products (spices and oils) chemical indicator TTC (Tetrazolium Chloride) was added. This changed from a clear colourless liquid to which are reputed to have antimicrobial properties; we are going to establish the Minimum Inhibitory red by growing bacteria. The broth-dilution method Concentration and then the Minimum Bactericidal using microtitre trays was used as this allowed us Concentration for each one. We are also hoping to to quickly and easily identify the Minimum Inhibitory form links with York University chemistry department Concentration. Unfortunately, none of the essential to enable us analyse the many different components oils had an effect on the growth of Staphylococcus epidermidis. However, the E.coli showed sensitivity to in the oils used.

4 of the 5 essential oils, in particular lavender, thyme and geranium, which inhibited growth during the first 24 hours, at the lowest concentration of 1/32%; 44

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Essential Oils, the Answer to Antibiotic Resistance? INVESTIGATION

Acknowledgements

Our thanks to Mr Colin Inglis, Boroughbridge High School and Professor Kevin Kerr, Harrogate District Hospital.

References

Zones of inhibition can be seen where the bacteria have been prevented from growing near the antimicrobial agent.

1. Karen Reeds. “This Booke of Sovereign Medicines”....

Collected of Maister Doctour ffecknam late Abbott of Westmynster.” Bulletin of the History of Medicine 72, no. 3 (1998): 543-543. https://muse.jhu.edu/ (accessed March 31, 2015).

Author Boroughbridge High School, North Yorkshire We are a very passionate group of year 10 students at Boroughbridge High School, and since we started a weekly lunchtime microbiology club after a conversation with Professor Kevin Kerr, Head of Microbiology at Harrogate Hospital, we’ve really fallen in love with science and even more with this project.

Authors: Alexander Stamos, Adam Dickson, Kayleigh Coates, Rebecca Longbottom, Holly Barnes, Emma Scott-Spivey, Joe Headford, Georgina Gill, Charles Grasby, Thomas Kennedy, Laura Bickerdike, Caprice Aspey, Laura Tee, Bethany Grout, Georgia Armitage, Bethany Grant ROYAL SOCIETY SPECIAL I ISSUE 17 I WWW.YSJOURNAL.COM

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INVESTIGATION Do Sports Drinks Really Work?

Do Sports Drinks Really Work?

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[TELEGRAPH]

Do Sports Drinks Really Work? INVESTIGATION

Abstract

Our investigation’s aim was to determine whether a sports drink containing glucose would improve athletes’ performance. We took five male students between the ages of 12 15 and, with their consent as well as their parents, conducted a test on them over the course of three weeks. We asked them to take one of three different drinks – Lucozade Sport, orange squash and water – then perform an 800m run. Participants were provided with a different drink each week before they performed the test, which happened a total of three times. The experiment showed that Lucozade Sport increased their performance the most, though our study was quite limited.

Method

Funding Statement

Royal Society Partnership Grant

Introduction

W

hen participating in sports, you need to stay hydrated in order to maintain performance levels1. The more you exercise, the more you respire due to the energy required for the working muscles in the body2. The following equation represents what happens during aerobic respiration: Oxygen + Glucose → Energy + Carbon Dioxide + Water Sports drinks containing glucose have been shown to be useful during endurance training and performances, however it has also been suggested that water hydrates you better in comparison, as you need to drink water to replace the

water lost when exercising3. Some people believe that sports drinks are ineffective, so we were interested in finding out whether this was true or not. The aim of our investigation was to determine the influence of Lucozade Sport, a widely available British sports drink that contains glucose, on performance in an 800m running time trial..

We recruited five male students aged 12 to 15 and collected some of their personal and physical details, alongside consent from their parents. We explained to them what we were doing and how they were going to contribute. Each participant was required to run 800m three times over three weeks, taking a different drink 25 minutes before each run. The three drinks were Lucozade Sport, orange squash and water. The experiment was done on a school 400m running track, during the spring in the late afternoon and the procedure was the same each week. We took the participants’ heart rates before and after each test using the method of the participant counting how many beats their heart completed in 6 seconds and multiplying that figure by ten. Once on the school field, we led the participants through a specific warm up including a pulse raiser and stretches. The pulse raiser consisted of jumping jacks and a short 30m jog and was followed by both static and passive stretches. Once the participants had completed the test they performed a cool down activity.

Results

The mean values for all the 5 participants’ personal information were as follows: Gender: Male Height: 159 cm Weight: 46 kg Age: 13.

The participants’ mean time for completing the 800m test when drinking Lucozade Sport was 2 minutes 58 seconds. The mean time when taking orange juice was 3 minutes 9 seconds. Finally, the mean time when drinking water before the test was 3 minutes 20 seconds. This result indicates that drinking Lucozade Sport enhanced the participants’ performance the most, followed by orange juice and then water. However, using a computer generated system that calculates averages, it seems that this result may not be reliable or significant enough. This supports the idea that sports drinks do not affect exercise performance at this level, though they may be effective for more high intensity long endurance workouts.

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The participants’ heart rates at the end of the exercises show that they worked at a high intensity.

The maximum heart rate for a 13 year old is 22013=207 bpm4. The participants’ mean heart rate after exercise was 180 bpm, therefore participants were working at 88% of their maximum heart rate.

Limitations of the study

With our project, there were a few limitations. Our main limitation was the number of participants we had. If there had been more participants, the results would be more reliable. This is because a larger sample of participants would have reflected the population in general more accurately. It was very difficult to select individuals due to students wanting to participant in other after school clubs. We could also have randomised the conditions to reduce any learning effect that might have occurred – participants’ performance may have been influenced by the fact they knew they were drinking either water, orange squash or a well-known sports drink.

Another limitation discovered was the timings between taking the drinks and completing the run.

Sometimes we would have to wait for participants to get changed and walking up to the field and performing the warm-up took time as well.

Participants also conducted the testing over three different weeks and the environmental conditions were difficult on each occasion. The temperature and weather conditions varied and this may have affected both the participants’ physiological conditions and their motivation. I believe that if we were to repeat the same test over the period of a year with the same participants, we would gain more results on how fitness levels improve with the help of sports drinks.

More research could be done in future to find out the most effective amount of time before exercise to drink sports drinks. In a recent study, University of Kent students found that post-exercise heart rate was lowest in the Lucozade Sport category, which we wouldn’t have expected. This could be another interesting area of study.

Figure 2: Giving our presentation.

Conclusion

We found that the participants’ performance in the time trial was best when they drank Lucozade Sport, followed by orange squash and then water. However, due to the limitations of our experiment this result may not be reliable. However, there are a lot of options for us to take this study forward and learn whether sports drinks really do what they say on the bottle.

Acknowledgements

We would like to thank our teacher, Mr Denness, who made it possible for us to complete the project and encouraged me to write this article. We would also like to thank the people who took part in our study, as well as the University of Kent and their Ambassadors who allowed Brompton Academy to use their facilities and who coached us through our investigation.

The Royal Society gave invaluable support; without them, We would have never learned about how science influences sports performance. Finally, I would like to acknowledge Young Scientists Journal for the opportunity to publish this investigation.

References

1. Kerr, P. (2012) “Keeping hydrated for exercise”, Bupa UK Health Information, Online.

2. BBC (2014) “Aerobic Respiration”, GCSE BBC Bitesize, Online.

3. Caldwell, J. (2007) “Sports Drinks: Are they effective in improving Athletic Performance?”, Online.

4. Mayo Clinic (2014) “Exercise intensity: How to measure it”, Online.

Author Brompton Academy, Kent The group first met together at the Sport Science workshops which took place at the University of Kent. This was the first time the group met and got to know one another. The dynamics of the group consistent of students in various year groups ranging from age 15 to 18 years old.

Students had to build a positive relationship quickly in order to achieve their goals for the project. In brief, the project lasted 5 months and involve a series of phases where the group learnt how to: use specialised sports measurement equipment; design a scientific study; collect data and analyse results and produce a scientific poster. The highlight of the project was a student-led presentation evening which took place at the Academy in June 2014, with a Gillingham F.C and leading Sport Scientists.

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Philosophical Transactions

REVIEW

Philosophical Transactions: a Historical Perspective Introduction

I

believe it is in human nature to tell stories. We tell them all the time: when we tell someone about an event, when we describe an idea. Countless stories have been told over the centuries, passed down and re-told by word of mouth, or copied down and spread around. Whether they are the stories of our life we tell daily or epic yarns we spin, humans have a compulsion to tell stories. Maybe it’s to leave our mark. After all, words last longer than humans. Maybe it’s a desire to share knowledge and imaginings, to let people into our worlds.

Scientific publishing is also just about stories.

These are the tales of those who have discovered something new, perhaps something exciting and amazing. If it is indeed human nature to tell stories, then it is only natural that there should be a way to share these stories of science. And that is the purpose of journals such as Philosophical Transactions, which was the first ever scientific journal and is still published today.

What is the importance of being able to share information in such a way?

There is great importance in being able to share information in scientific journals; it enables us to use what others have discovered and incorporate it in our own work, to help develop our own ideas, all the time leading towards greater understanding.

Long ago ancient people made up stories of gods pulling the sun across the sky in golden chariots to try to explain the sun’s movement during the day, and understand why the world is the way it is. Now scientific papers help us understand such phenomena, and make sense of our complex world.

Publishing our ideas in scientific journals also means work can be peer reviewed, so others can test theories themselves to confirm results.

How much impact does the publication of discoveries have?

When discoveries are published it means that the information is freely available. Once everyone can read about it, people’s conceptions can be changed.

If Copernicus and Galileo had never published works proposing the heliocentric model we might still think that the sun orbited the earth! It can change the way we think and see the world.

How has the accessibility of journals like Philosophical Transactions changed over the years?

When it first was published in 1665 Philosophical Transactions cost one shilling a month. The accessibility of information meant that scientists could use information proposed by other scientists to advance their own work, but everyone got the credit they deserved. It was much more effective than the private letters previously used to communicate new ideas in science.

However, the circulation was largely restricted to the scientific community: many ordinary people couldn’t afford the one shilling a month, and many more still simply couldn’t read. The journal was actually published at a loss each month. It was not until the post-war period mid-20th century that it began to make a profit, when universities, industry and government began to subscribe to the journal. University researchers found science more accessible, scientific journals were more affordable, information more available.

And again we return to the idea that if the information is more available others can build upon it to advance our understanding. In 1997 the journal went online, meaning it was available to other countries.

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Philosophical Transactions

What are the Philosophical Transactions?

Philosophical Transactions is the world’s first and longest-running scientific journal.

It is published by The Royal Society

The term “philosophical” refers to “natural philosophy”, which was the term for “science” before the 19th Century

Please note all dates are in the Julian calendar, as the United Kingdom in converted to the Gregorian calendar in 1752 (For the 17th Century the Gregorian dates were 10 days ahead of Julian dates)

The first issue was published on 6th March 1665, with a charter granted by King Charles II Henry Oldenburg (1619-1677), German theologian and natural philosopher came to London in 1653, as a diplomat. He forged a strong relationship with many in UK and Europe. Robert Boyle was his lifelong patron.

At the foundation of the Royal Society he became the first Secretary and became the founding editor of the Philosophical Transactions. Oldenburg published the journal at his own personal expense, but the journal did not generate any profit. He put out 136 issues of the Transactions before his death in 1677.

The principal ideas of the new journal can be traced in a series of letters between Henry Oldenburg, left, and Robert Boyle, right

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Philosophical Transactions

REVIEW

Contents of the First Philosophical Transactions 1. Henry Oldenburg: Epistle Dedicatory A quote “So that no man can from these Glimpses of Light take any just Measure of Your Performances, or of Your Prosecutions; but every man may perhaps receive some benefit from these Parcels, which I guessed to be somewhat conformable to Your Design.

This is my Solicitude, That, as I ought not to be unfaithful to those Counsels you have committed to my Trust, so also that I may not altogether waste any minutes of the leisure you afford me. And thus have I made the best use of some of them, that I could devise; To spread abroad Encouragements, Inquiries, Directions, and Patterns, that may animate, and draw on-universal Assistances” 2. Introduction 3. An Accompt of the Improvement of Optick Glasse 4. A Spot in One of the Belts of Jupiter “The Ingenious Mr. Hook did, some moneths since, intimate to a friend of his, that he had, with an excellent twelve foot Telescope, observed, some days before, he than spoke of it, (videl. on the ninth of May, 1664, about 9 of the clock at night) a small Spot in the biggest of the 3 obscurer Belts of Jupiter, and that, observing it from time to time, he found, that within 2 hours after, the said Spot had moved from East to West, about half the length of the Diameter of Jupiter.”

Modern image of Jupiter showing the Great Red Spot Mr Robert Hooke reported

5. The Motion of the Late Comet Praedicted 6. An Experimental History of Cold: Robert Boyle 7. An Account of a Very Odd Monstrous Calf Oldenburg described how a butcher, having killed his fatted cow, found her womb full and opened it. Inside was a calf, “whose hinder Leggs had no Joynts, and whose Tongue was, Cerberus-like, triple . . .”

8. Of a Peculiar Lead-Ore of Germany, and the Use Thereof 9. Of an Hungarian Bolus, of the Same Effect with the Bolus Armenus 10 Of the New American Whale-Fishing about the Bermudas 11. A Narrative Concerning the Success of Pendulum-Watches at Sea for the Longitudes 12. The Character, Lately Published beyond the Seas, of an Eminent Person, not Long Since Dead at Tholouse, Where He Was a Councellor of Parliament Huygens first pendulum

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Philosophical Transactions

What have the importance of the group and the individual been to the publishing of Philosophical Transactions?

Phil Trans was the idea of one man, Henry Oldenburg, and he published and edited it himself. So without this one individual, Philosophical Transactions would not exist. But these journals rely on many people to contribute work and within one paper there are often collaborations of several people. And of course, the underlying principle is the sharing of information, the retelling of these science stories.

Original Stages for publication by The Royal Society

How will journals such as Philosophical Transactions adapt in the future to accommodate new generations?

The journal is already online, which is the fastest way to reach people and share information in these times, so perhaps the way to accommodate future generations is to incorporate them in it, to raise awareness and be inclusive. Also, to nurture an interest in science from a young age, to encourage discovery and the sharing of these discoveries may be key. To invite student scientists to celebrate learning through projects just like this one, to invite them to tell their stories.

This is exactly what the Young Scientists Journal is doing, involving us, the younger generation, in the field of scientific communication and making us aware 350 years on, reminding us of the importance of scientific publishing that will surely only grow with time.

Registration of the date of any new matter whereby the honour of the invention will be reliably preserved to all posterity

Dissemination “...all ingenious men will thereby be encouraged to impact their knowledge and discoveries”

Further reading:

1. Fyfe, Aileen, Julie McDougall-Waters, and Noah Joseph Moxham.

“Philosophical Transactions: 350 Years of Publishing at the Royal Society (1665–2015),” 2014.

2. https://research-repository.st-andrews.ac.uk/bitstream/10023/6058/1/ Fyfe_2014_RS_Philtrans.pdf 3. “History of Philosophical Transactions | Royal Society. https://royalsociety.org/ publishing350/history-philosophical-transactions 4. Partridge, Linda. “Celebrating 350 Years of Philosophical Transactions: Life Sciences Papers.” Philosophical Transactions of the Royal Society of London B: Biological Sciences 370, no. 1666 (April 19) 2015. http://rstb. royalsocietypublishing.org/content/370/1666/20140380 5. “Philosophical Transactions of the Royal Society - Wikipedia, the Free Encyclopedia.” http://en.wikipedia.org/wiki/Philosophical_Transactions_of_the_ Royal_Society

Author Valentine Bailey-Beckett Hi I’m Valentine, I’m 15, and am at school at Bodmin College, I have a deep passion for science. I thoroughly enjoyed researching for this article and feel privileged to be part of such an historic year for scientific publishing.

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Certification (peer review), all published work should be revised by members of the council of the Royal Society.

Horse Chestnut Trees INVESTIGATION

What Ails our Horse Chestnut Trees and How Can we Save Them?

Abstract

The horse chestnut leaf miner insect causes the brown, see-through blotches on the leaf as the Cameraria ohridella caterpillar lives and feeds in between the two surfaces of the leaves, creating mines. Several mines can merge together causing the leaves to dry up and turn brown. Eventually the leaves fall early, despite it usually only being towards the end of summer. The premature leaf loss means an early autumnal look. This project investigated the effects of natural predators (such as parasitoid wasps and blue tits) on the caterpillars, as well as exploring the potential for control of other interventions such as pheromone traps, insecticides and leaf sweeping.

Funding Statement

Royal Society Partnership Grant

Introduction

T

he white flowering horse chestnut (Aesculus hippocastanum) is a deciduous broadleaf tree native to the Balkan Peninsula. The first trees were planted here in the early 17th century by John Tradescant the Elder, an Elizabethan gardener and botanist [who studied at The King’s School Canterbury where this journal was founded], and they soon became a regular ornamental feature in the gardens of stately homes across the country. It is rarely found in woodland, but is a common sight in parks and gardens and along roads. Cameraria ohridella, the horse chestnut leaf miner of the Gracillariidae family, is a pest that has recently become apparent in Europe and attacks this tree almost exclusively.

This invasive moth species was first observed in 1984 and described as a new species in 19861 . It has however been noted in herbarium specimens from the late 1800s. The first sighting in the UK of the leaf mining moth, Cameraria ohridella, was on horse chestnut trees, Aesculus hippocastanum, in the London Borough of Wimbledon in July 2002 with signs of adult moth activity in the same area being noted in mid May 20032 .

The moth caterpillars feed by tunneling between the two epidermis layers of the leaf. Severely damaged leaves shrivel and turn brown in late summer and then fall prematurely. It is inevitable that the trees will be weakened by this in the long term and could become more vulnerable to attacks from pathogens.

Scientists think that the horse chestnuts may then

The effect of Cameraria Ohridella on a horse chestnut tree

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INVESTIGATION Horse Chestnut Trees

become more susceptible to the fatal bleeding canker disease, which causes trees to lose branches and bark, and already affects more than half of all chestnut trees in some parts of the UK3.

Life cycle of the horse chestnut tree The average lifespan of a horse chestnut tree is 300 years. The tree can grow to a height of around 28m. It begins as a conker seed which sprouts into a sticky bud. A green stem grows from the bud with five to seven small leaflets on it; each leaflet has toothed edges and a pointed tip. These leaflets radiate to form the familiar leaves of a horse chestnut tree that arrange around the green stem like a canopy. Beautiful large flower spikes appear in May – individual flowers have four to five fringed petals, which are white with a pink flush at the base.

The green stem grows to form its trunk. In autumn, the tree produces conkers, contained in spiky green husks, which drop to the ground.

Value to wildlife The flowers provide a rich source of nectar and pollen to insects, particularly bees. Deer and other mammals eat the conkers4.

How do we use the horse chestnut tree?

Horse chestnut trees are ornamental trees and were largely planted for their attractiveness. They have an attractive shape and beautiful flowers which makes them really desirable in parks and village greens. However, they have little commercial value when compared to trees used in forestry or fruit production. Horse chestnut timber is a pale creamy white to light brown with a smooth, soft, fine texture. It’s not very strong and is therefore not used commercially, but its soft texture makes it ideal for carving. The most famous use of the horse chestnut is in the game of conkers. The first record of the game is from the Isle of Wight in 1848. Various extracts from horse chestnut leaves and fruits which contain the active ingredients aescin or aesculin, are marketed as herbal remedies, because of their antiinflammatory properties. Other uses of the conkers include as additives in shampoo and bubble bath.

Chemicals extracted from conkers can be used to treat strains and bruises4.

Threats

Horse chestnut has been found to be susceptible to Guignardia leaf blotch, a fungal disease5. Trees can also be affected by bleeding canker, which can lead to their death5. The horse chestnut leaf miner can be found on trees in huge numbers, causing the foliage to turn brown and fall early. The trees may also suffer from and horse chestnut scale insect.

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History of introduction and geographical spread of the moth infestation The moth species was noticed for the first time in the early 1980s in the vicinity of Ohrid Lake in Macedonia, and in 1986 was described as a new species1 .

Since that time its gradual spread northwards was noted, and the species reached Croatia, Hungary and Romania within a few years. It has now spread through central and eastern Europe. It is not clear why it has made such a dramatic impact since it is not new to Europe. Cameraria ohridella has been found to be present in numerous herbarium collections of native horse chestnuts in Albania and Greece going back to 18796 . It is thought that it shifted from an Acer to the horse chestnut. Leaf miners in general can be found on a large variety of plants but the effect is usually not as devastating as in this case.

Life cycle of the horse chestnut leaf miner8 Caterpillars are the larval stage of the moths. The caterpillar hatches from a tiny egg, then spends its time eating and growing. This larval stage usually lasts from two weeks to about a month. As caterpillars grow, their exoskeleton becomes too tight for them, so they moult (lose their old exoskeleton).

Then the caterpillar pupates, covering itself with a protective shell, and metamorphosing into an adult moth. There can easily be 3 generations of moths per year. Caterpillars mostly eat the leaves of a particular type of flowering plant or tree, using their powerful jaws (mandibles). Caterpillars are very limited in their diet; many species will only eat the leaves of a single type of plant. They usually eat only the plant that the females carefully chose to lay their eggs on. Most caterpillars eat the leaves from the outside. However leaf miner moth caterpillars live and feed between the two layers of the leaf.

What is leaf mining?

A leaf miner is a species, the larva of which lives and feeds for a part of all of its time between the epidermal layers of a leaf. The eggs of leaf mining insects are laid on the leaf surface, whereupon the larvae must cut into the leaf, or the adult female cuts holes in the leaf and deposits eggs. The larvae may spend their entire existence in the leaf or mine initially and then feed externally when larger. The head is often wedge shaped to separate the epidermal layers, legs, antennae and eyes are small and reduced.

Why do we care about saving the trees and not the moths?

Both the horse chestnut tree and the Cameraria ohridella are invasive species. We consider the moths to be pests because they harm the trees that we chose to plant. The moths have come uninvited.

People like trees. We like to see leafy trees from their

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windows, to sit in green spaces, and to sit and play in the shade of trees. On the other hand in general we find small moths flying around us annoying even though both the trees and the moths are very attractive.

Horse chestnut tree moths The small adult moths are around 4 mm long.

They are metallic orange-brown with white streaks.

The legs equally banded white and black. They are diurnally active with peaks of activity from midmorning to mid-afternoon at moderate temperatures.

The food web starting from the horse chestnut tree The basic food material of the food chain is synthesized by the horse chestnut leaf (producer), which is consumed by the larvae of the horse chestnut moth (primary consumer), which itself in turn is predated by the blue tit (secondary consumer). Competing with the blue tits are a number of parasitoid wasps. A parasitoid is an animal that lives inside its host (like a parasite), but always kills its host (like a predator does, but unlike parasites). Predators (external) kill what they are feeding on. Parasites (are commonly internal but can be external) usually don’t kill what they are feeding on. The adult parasitoid wasp has a long ovipositor which she uses to insert a single egg through the leaf cuticle into the body cavity of the larva of the moth.

The wasp larva feeds within the moth larva, and eventually kills it3 .

Aims

We noticed that there was extensive early browning of the horse chestnut trees, which we found was caused by the horse-chestnut leaf-miner, and we wanted to find out what the cause was and if anything could be done to stop this. We investigated the following possibilities of control: • Natural predators (parasitoid wasp and blue tit) • Collecting and burning or burying fallen leaves in autumn to destroy the overwintering pupae • Pheromone traps that attract and kill male moths.

• Spraying with insecticide and root/soil treatment.

The soil is drenched with a systemic insecticide which is then is then absorbed by the roots and then distributed throughout the rest of the tree.

Horse Chestnut Trees INVESTIGATION

Brown leaf mines were obvious in July and by early September there was substantial browning of the leaves.

Adaptations of the larvae We cut open leaf mines and released caterpillars into a petri dish. We then made drawings of the caterpillars and observations about their adaptations.

The leaf miners (caterpillars) are small and dorsoventrally flattened. They have an obvious mouth part and deep indented segments. They are translucent and can be seen when the leaf is held against the light. Leaf miners are relatively small insects (4 mm long), physically constrained by the thickness and area of leaves they occupy.

What advantages does mining give the leaf miner caterpillar?

• Some protection from natural enemies (predators, parasites, pathogens) • Protection from the physical environment (desiccation, UV radiation, dislodgment by weather) • Selective feeding to maximize intake of most nutritious tissues There are approximately 10,000 described species of leaf miners. Lepidoptera includes more leaf mining families and species than any other order.

The effectiveness of the different types of control of the leaf miner

1. Natural control by parasitic wasps Leaves from an infected horse chestnut tree were collected and stored in zip-lock bags for two weeks on a cool and dark shelf.

We sealed the bags so not even tiny insects could escape. We then recorded the number of adult Cameraria ohridella moths, parasitoids, and ‘other insects’ that had hatched.

A Horse Chesnut Leaf Miner [British Lepidoptera]

Investigating the leaf miner

Number of leaf mines (15th July 2014) We worked in groups to visually estimate the number of horse chestnut leaf miner in one tree. We counted the number of the leaf miners in a small section of the tree and then scaled up to make an estimate for the tree. We estimated that there were 250,000 – 500,000 leaf miners per tree.

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INVESTIGATION Horse Chestnut Trees Table 1

Estimation of numbers of insects that emerge from the leaves. * Please see Conker Tree Website for Insect Identification Chart

Number of moths(metallic orange, brown with white stripes; 4 mm long)*

25 30 117 35 26 49 45 79 17 59 46 42 29

Number of wasps (pest controllers) (bodies with very narrow ‘waists’ and transparent wings;2-3 mm long)* 4 7 35 19 5 21 11 7 5 7 6 8 6

Other insects

0 0 3 2 0 0 0 0 4 2 0 0 0

62 12 0 41 8 1 21 10 0 Total = 724 Total = 171 Total = 12 There were 171 wasps altogether which means 171 horse chestnut tree leaf miner larvae were killed by the larvae of the parasitic wasps. If this had not happened, there would have been 894 leaf miners on 16 leaves (56 per leaf). % parasitoid wasps = 19% This ratio may vary depending on whether the leaves were collected from sunny or shady parts of the tree or whether they were on the edge of canopy or not.

Other studies report rates of parasitism of less than 10%10.

This does show that the wasps that prey on the moth’s caterpillars aren’t present in high enough numbers to control the moths’ spread.

2. Natural control by birds Blue tits learned to steal cream from our milk bottles in the 1980s, and they have now discovered that horse chestnut trees are absolutely loaded with caterpillars. Caterpillars are an important food

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source for blue tits, which feed them to their young.

It’s estimated that blue tit chicks eat 35 billion caterpillars a year. It’s not yet clear how many horse chestnut leaf miner caterpillars are being eaten by the birds, but if they were to start eating a substantial number it would help the horse chestnut tree.

We examined the leaves for v-shaped tears as evidence of ‘bird attack’. The majority of the leaves that were accessible did not have any v-shaped tears.

However there was patch on the tree in the orchard which is more secluded that showed evidence of ‘bird attack’. Each leaf was examined and v shaped tears were counted by 2 different people.

Table 2 Bird attack counts on horse chestnut tree leaves (18/9/14) Count 1 Count 2 Count 3 1 2

0 23

0 20

0 21.5

3 4 5 6 7

49 30 7 44 14

65 31 8 43 15

57 30.5 7.5 43.5 14.5

It was difficult for us to estimate contribution that birds were making to the controlling the numbers of leaf miners because we only looked at a small sample of leaves.

3. Control by pheromone traps The main component of the sex attractant (pheromone) released by the females of the horse chestnut leaf miner has been identified as E,Z-8,10Tetradecadienal12.

We used pheromone traps to catch male moths. This reduces mating and therefore egg laying. We started off by using a castellation moth trap. The moth is drawn by the pheromone attractant (obtained from Harrod Horticultural) into small holes in the side that are only big enough for moths.

Moths caught in the castellation trap (8th July -9th September 2014) We weighed the content of the trap and estimated that 30, 000 moths had been captured over a period of two months. This is about a tenth of the number we had estimated on each tree in July after the 1st of the 2 or 3 generations. If each female produces about 30 eggs then this trap caught an estimated 1% of the total during the whole summer.

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Horse Chestnut Trees INVESTIGATION

Blue tits, saviour of the horse chestnut tree?[science It was difficult to count the number of moths in the castellation trap so we switched to delta traps in later studies. The base of the delta trap was covered with incredibly sticky card (20 cm x 20 cm) to which the moths stuck. As controls we put up delta traps with sticky card but no pheromone. The traps were put up for periods of one hour, 24 hours of one week. At the end of the time period the traps were collected. The pheromone lure was removed and the sticky card was covered with transparent self-adhesive film. This was scanned, printed and enlarged to A3 paper.

The pheromone trap was very specific. All the moths trapped on the sticky card were identified as being Cameraria ohridella.

Table 3 Number of moths counted Counted by Number of Moths Catriona 1026 Mia 886 Lara 1059 Zoe 896 Elizabeth 885 Hannah 962 Mean 952

It was difficult to count the moths. We noticed that the counts varied when different people counted them. After this we decided that we needed to make two independent counts of the number of moths trapped each time.

Table 4 Cameraria ohridella male moths caught in Delta traps in the grounds of La Sainte Union Catholic School Treatment Time Number of moths mean ±SD Pheromone and One hour 258 ± 35 sticky card Pheromone and One day 568 ± 129 sticky card Pheromone and One week 1473 ± 397 sticky card Sticky card One week 34 ± 30 alone Traps with the pheromone caught a substantial number of moths compared to control traps (sticky card only). The numbers of moths caught in a day are not 24 times that caught in an hour because the moths are diurnal and are only active for a few hours

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daily]

INVESTIGATION Horse Chestnut Trees

(mid-morning to mid-afternoon). The numbers of moths caught in a week are not seven times those caught in a week because the moths are not active on cold and wet days. In retrospect we also realised that when we put the traps up we were more likely to avoid wet days.

The pheromone traps caught many thousands of leaf-miner moths but because this is only a small percentage of the total number of moths, traps by themselves will not provide a complete solution and will have to be part of an overall strategy.

4. Removing over-wintering leaf litter Early in the season (July), we noticed that the browning of the leaves is more prominent at the base of the tree. This is consistent with the moths emerging from the fallen leaves and spreading upwards first to the lower leaves.

We collected leaves from the base of the tree. It was difficult to count the pupae in dry leaves. However we found that if we soaked the leaves and then held them against the light it was possible to count the pupae quite easily.

The horse chestnut tree has compound leaves, with 5 to 7 leaflets.

We collected fallen leaves from under the horse chestnut tree. We counted the number of pupae in 120 leaflets.

The range= 0 – 63 pupae per leaflet The average length of leaflets was 15.4 cm The average number of pupae in a leaflet was 19.5 How could the infestation progress?

There can easily be 3 generations of moths per year.

Our estimation: First generation • Number of leaves at the base of tree = 100 • Number of leaflets per leaf = 5 • Total number of leaflets = 100 x 5 = 500 • Number of pupae per leaflet = 20 • Possible total number of pupae = 500 x 20 = 10,000 • Number females (5,000) x number of eggs (30) = 150,000 eggs If we estimate that there could be at least 100 fallen leaves in the vicinity of the tree. Each leaf could have 5 leaflets containing 20 pupae each. In this case potentially 10,000 moths could emerge and be 58

waiting to infect the tree in early summer. If half of these are females we could expect 150,000 eggs.

Nevertheless the large amounts of leaves at the base of the trees would be expected to have a positive impact on the population of the leaf miners that infest the horse chestnut trees. We would expect that the more dead leaves lying around near the tree, the bigger the infestation the following year.

Second generation Let’s assume that all the moths from the first generation survived and 150,000 moths hatch Let’s assume that 75,000 are female Number females (75,000) x number of eggs (30) = 2,250,000 eggs Third generation Let’s assume that all the moths from the second generation survived and 2,250,000 moths hatch Let’s assume that 1,125,000 are female Number females (1,125,000) x number of eggs (30) = 33,750,000 eggs In reality the number will be smaller because not all pupae, moths or eggs will survive. Nonetheless the number of potential moths is formidable bearing in mind that the calculation is based on just a hundred leaves.

By removing the fallen leaves in autumn and early spring, the pupae of Cameraria ohridella hibernating in the leaf mines are also removed, and consequently the number of adults emerging in the following spring will be reduced.

5. Use of insecticide The control of the horse chestnut leafminer with chemical products is very difficult since it lives inside the leaf mines during most of its life cycle. Bark and canopy sprays of diflubenzuron an insect growth regulator (trade name Dimlin Flo) has been shown to be successful if the whole canopy can be sprayed.

Spraying large trees with insecticides is not a viable option in urban areas.

One effective chemical control measure is the injection of insecticide imidacloprid (‘Admire’) in the trunk or soil13,14. Imidacloprid is a nicotine based insecticide which is used to control insect and mite pests of a range of fruit, vegetable and ornamental crops.

The leaf miner can cause halving of conker weight and also up to 48% reduction in growth

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and germination rates, and 16-98% loss in photosynthestic energy from late June to September with premature leaf loss14. Pheromone traps may not provide effective control and we may have to turn to insecticides.

Red versus white flowered horse chestnuts This red-flowered hybrid is a cross between our common horse chestnut and the red buckeye Aesculus pavia from the southern United States.

It has been in cultivation since the 1820s, often grown in avenues and parks where its large shapely stature can be well appreciated. It is often seen as the smaller, deep pink-flowered cultivar known as ‘Briottii’. The common horse chestnut Aesculus hippocastanum is very susceptible to infestation by the leaf miner. However, the red-flowering hybrid (Aesculus x carnea) is very resistant.

Visible difference between white and red flowered horse chestnut tree leaves

Leaves of the red flowered horse chestnut tree were glossier, tougher, more crinkled and darker green when compared to the white flowered tree.

The leaves of the red flowered horse chestnut tree felt thicker. We placed glass slides (2.5 x 7.5 cm) on the leaves and cut around them so that we had equal sized pieces from the leaves of the two types of trees and compared their masses. We avoided the thick mid vein and any areas with leaf mines.

Table 5 Comparison of the mass of white and red flowered horse chestnut tree leaves White flowered Red flowered horse chestnut horse chestnut trees Aesculus trees Aesculus hippocastanum carnea

Wet mass (g) Dry mass (g) Number of strips Wet mass per strip (g) Dry mass per strip (g)

6.49 2.09 35

8.07 3.13 23

0.185

0.351

0.060

0.136

Horse Chestnut Trees INVESTIGATION

The mass of the red flowered horse chestnut trees was approximately twice that of the white flowered trees regardless of whether we looked at wet or dry weight indicating the leaves were thicker or denser.

The caterpillars seem unable to feed successfully on these leaves.

In late summer red flowered trees that are near white flowered trees were beginning to show signs of moth infestation. Close examination showed that the caterpillars had died and the mines were short in length. It seems possible that in the future when the Aesculus hippocastanum trees have been decimated the leaf miner moths may adapt to feed on the Aesculus carnea. The present leaf miner problem only became apparent in the 1980s and it is thought Cameraria ohridella switched host trees at that time.

There was some evidence of leaf miner infestation at base of red flowered leaves. All the mines in the red flowered leaves were brown and small suggesting that they were old and that the larvae did not grow to pupation.

Examination of trees in the vicinity

Some trees had a ‘typical tree’ shape with a clear trunk and canopy whereas others had leaves also growing near the base of the tree ‘leafy base’.

See Table 6

Discussion of Results

The leaves of the horse chestnut tree have been found to be susceptible to infestation by caterpillars of a leaf mining moth. The caterpillar lives between the two epidermal layers of the leaf feeding on the nutrients there, causing browning of the leaf, premature leaf fall and reducing the size and therefore the viability of the trees fruit – conkers.

The food web for the horse chestnut tree and moth The larvae of the horse chestnut moth Camararia ohridella feeds on the leaves of the horse chestnut tree. The caterpillar itself is in turn is predated by the blue tit (secondary consumer). We found several v-shaped tears, with no remains of a miner inside the mine, indicating that the leaf had been opened by a beak. Blue tits also feed on greenfly and aphids which are pests in gardens, but Blue tits are in turn predated by e.g. sparrow hawk. Competing with the blue tits for the caterpillars are a number of parasitoid wasps. These lay eggs inside the moth larvae. The parasitic wasp larva then feeds within the moth larva, and eventually kills it.

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INVESTIGATION Horse Chestnut Trees Table 6 Red flowered and White flowered trees in the neighbourhood Location of Red flowShape Signs of infestation? ered horse chestnut trees Aesculus x carnea Highgate Road

Leafy base

Some short leaf mines at base of tree

Hampstead Heath by the coffee shop Hampstead Heath by the benches Hampstead Heath small tree in field opposite benches Hampstead Heath Back of field La Sainte Union School North wing path

Typical tree

No signs of infestation

Leafy base Typical tree

Few short mines at the base of tree No signs of infestation

Typical tree

No signs of infestation

Leafy base

Very few leaves at base of trunk affected Canopy not affected

Unfortunately although both the parasitoid wasps and the blue tits reduce the number of moth caterpillars, at present neither are able to have a sufficiently substantially effect to control the number of leaf miners nor on their effects on the tree.

Without an efficient predator for horse chestnut leaf miner, the tree’s future is in jeopardy.

Possible treatments outside of the natural food chain.

Pheromone traps and tree root treatment with insecticides may help, but treatment of 0.5 million trees in this way would be an unsustainable financial burden for the UK. The cost of one pheromone trap with three pheromone lures needed per tree per year is about £20. The numbers of moths caught by the traps indicate that this method by itself will not be sufficient. The cost of systemic soil/root treatment is about £300 per tree per year. This may be more effective that the pheromone traps but is not without its problems not least of all the cost.

Consequences of not treating the tree The inability of natural predators to limit the moth infestations may change the country’s scenery.

Horse chestnuts have been grown as ornamental trees in urban landscapes, particularly in avenues or along roadsides for their spectacular blossom during spring. They were introduced to Britain in the 16th Century. The early browning of the leaves by the leaf miner is therefore a serious problem. Trees that were planted for their attractiveness start to look withered 60

White flowered horse chestnut trees Aesculus hippocastanumin the vicinity?

Two trees nearby.

Leaves more brown than green and infestation throughout the tree No white tree in the immediate vicinity No white tree in the immediate vicinity No white tree in the immediate vicinity No white tree in the immediate vicinity White trees adjacent.

Leaves more brown than green and infestation throughout the tree

and unattractive. The horse chestnut tree has had to contend with bleeding canker as well as the leaf miner disease and so is at serious risk.

“The horse chestnut tree has had to contend with bleeding canker as well as the leaf miner disease and so is at serious risk.”

Nurseries have stopped planting horse chestnut saplings because there is no cure for infected trees – which means that as the trees die they are being replaced with different species. Horse chestnut tree sales fell by 98 per cent because of pests and diseases15. In 2011 at Barrington Court (a National Trust Tudor manor house), near Ilminster in Somerset, the last of an avenue of 93 conker trees that lined the driveway for nearly a century was removed and replanted with a variety of oak. In Cambridge University, the authorities will not replace horse chestnut trees suffering from bleeding canker along the city’s Backs16. Despite horse chestnuts being relatively new comers to the UK (1600s) they have become a traditional part of our landscape.

Beautiful and shiny conkers fall in the autumn. The first recorded game of conkers was in 1848 and this has become part of our culture.

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Horse Chestnut Trees INVESTIGATION The National Woodland Inventory of Woodland Trees estimates there are 470,000 horse chestnut trees in Great Britain: • England: 432,000 • Scotland: 29,100 • Wales: 11,100 Three-quarters found in towns and cities. Most of the rest are in landscaped parklands. We seem to be on course to lose our conker trees.

Replacement of horse chestnut trees with other trees will be very costly. We also have the possibility that Cameraria ohridella may switch host trees.

One possible solution

It may be time to follow for the UK to follow Berlin’s example where there is programme encouraging everyone to take part in raking up and clearing every single horse chestnut tree leaf. Householders, the unemployed and school children all take part.

It is considered to be every citizen’s civic duty to participate in the clearing of the leaves. Involving the community in this way may have many social benefits encouraging social interaction, interest and responsibility for the environment. Research has shown that leaf clearing can be done any time from when the leaves fall until spring17. The leaves do not have to be removed from the vicinity of the trees as long as they are covered or in bags until after the moths have hatched and died.

References

1. Deschka, G. and Dimić, N. 1986, Cameraria ohridella n. sp. aus Mazedonien, Jugoslawien (Lepidoptera, Lithocelletidae), Acta Entomol. Jugosl. 22:11-23 2. Horsechesnut 3. Conker tree science website 4. Woodland Trust website 5. OPAL and the Tree Health Survey 6. Lees, D. C., Lack H. W., Rougerie R., Hernandez-Lopez A., Raus T., Avtzis N., et al. (2011). Tracking origins of invasive herbivores using herbaria and archival DNA: the case of the horse-chestnut leafminer. Frontiers in Ecology and the Environment 7. Species 8. Photo 9. Our Web of Life 10. Svatos, A., Kalinová, B., Hoskovec, M., Kindl, J., Hovorka O. and Hrdy I. 2001, Identification of Cameraria ohridella sex pheromone and its possible use in horse chestnut protection Pheromones for Insect Control in Orchards and VineyardsIOBC wprs Bulletin Vol. 24(2) pp. 5-12 11. Ferracini, C. and Alma, A. 2008, Crop Protection, How to preserve horse Chestnut trees from Cameraria ohridella in the urban environment 27: 1251-1255 12. G.C. Percival et al. 2011: The impact of horse chestnut leaf miner (Cameraria ohridella Deschka and Dimic; HCLM) on vitality, growth and reproduction of Aesculus hippocastanum L., Urban Forestry & Urban Greening 10 (2011) 11–17 13. Daily Mail 14. Hort Week website 15. Kehrli, P. and Bacher S. 2003, Date of leaf litter removal to prevent emergence of Cameraria ohridella in the following spring, Entomologia Experimentalis et Applicata 107:159162 16. P. Kehrli and S. Bacher (2004): How to safely compost Cameraria ohridella-infested horse chestnut leaf litter on private compost heaps, JEN 128(9/10) 707–709 17. Germany

Below: Analysing Tree Samples

Acknowledgements

We would like to thank Dr Pari Collis, our teacher (La Sainte Union Catholic School, London) and Dr Michael Pocock, our Royal Society Science Partner (Centre for Ecology & Hydrology, Wallingford, Oxfordshire) for their guidance and encouragement.

Author

La Sainte Union Catholic School, Highgate, London This investigation was carried out by girls in Year 10-11 pupils at La Sainte Union Catholic School in Highgate, London, at the time of this research. The project was mainly done in an after school Science Club. Authors: Tito AdeOguns, Ursula Agyeman-Frempong, Elisabeth Azzopardi, Sharon Bonsu, Ariane Forien, Grace Gannon, Catriona Gilmour, Zoe Hartigan, Oghogho Igbineweka, Dea Loughlin, Mia Oliver, Lara Rosa, Hannah Sullivan and Ellie Themistokleous ROYAL SOCIETY SPECIAL I ISSUE 17 I WWW.YSJOURNAL.COM

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INVESTIGATION The Darkling Beetle for Exploring “–omic” Science.

The Darkling Beetle for Exploring “–omic” Science.

Abstract

The beetle Tenebrio molitor (often referred to as mealworm) is a relatively easy-to-manage insect that possesses a range of features that suggest it may be suitable for practical classes in schools. It is relatively inexpensive in the larval form, it is available from virtually all pet shops and it can be purchased both live and in a freeze-dried form, facilitating some biochemical experiments. The larvae are relatively large (between 1-5cm), the beetles are flightless, but easily visualized for anatomical studies, and they are harmless. In fact the mealworm is recommended by the WHO as a dietary supplement owing to its high protein levels per gram dry weight. In short, it is inexpensive, easy to handle, widely available – and nutritious!

“-omics” informally refers to a field of study in biology ending in -omics, such as genomics or proteomics, the study of the genome and proteome respectively.

Funding Statement

Royal Society Partnership Grant

Introduction

Tenebrio molitor is sometimes called the darkling beetle, or mealworm and the various stages of its life cycle are shown in Figure 1. Over approximately 2 months, larvae, obtained from any pet shop, can be kept on a diet of bran and sliced apple. During this time the eggs will become larvae, larvae will pupate and adult insects will appear after around 6 weeks, 62

on average. No special conditions are required and the insects can be maintained at all stages of development in simple plastic boxes.

The larvae, pupae and adult beetles can be used to demonstrate the key features of insects and using simple lenses. Students were able to draw annotated diagrams of these three stages. The eggs, however, are virtually impossible to isolate under the cultivation conditions used here, but one year into this project, students have been able to segregate the

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The Darkling Beetle for Exploring “–omic” Science. INVESTIGATION

various stages of development and to observe infant larvae develop into mature (full size) larvae, prior to the formation of the pupae and emergence of the beetle.

Methods

Biochemical fractionation of mealworm larvae for proteomics: The availability of freeze-dried larvae provided us with the opportunity to develop a robust method for the extraction of larval proteins. Students (approximately 100) were divided into groups of 5 and asked to devise a method for extracting protein using a range of mechanical breakage methods in conjunction with the addition of a physiological buffer (phosphate-buffered saline at pH 7.6).

“Mechanical Breakage is the separation or breaking of DNA strands into pieces.”

The success of the extraction procedure was determined by the visual yield of protein from a given mass of mealworm larvae. Thereafter the quality of the protein extracts was determined by the range of proteins identified by SDS polyacrylamide gel electrophoresis, and subsequent staining with Coomassie Blue.

“Polyacrylamide gel electrophoresis (PAGE), describes a technique widely used in biochemistry, forensics, genetics, molecular biology and biotechnology to separate biological macromolecules, usually proteins or nucleic acids, according to their electrophoretic mobility.

Mobility is a function of the length, conformation and charge of the molecule.”

A homogenizer is a piece of laboratory equipment, the modern equivalent of pestle and mortar!

This method was then applied to a single mealworm.

Individual live mealworm were frozen to kill them, the frozen individual larva was then distributed to each group and protein extracted as shown in the flow diagram (Figure 2). Samples were then separated into soluble and insoluble material following centrifugation in a bench top micro-centrifuge, at full speed. The soluble fractions were subsequently prepared for analysis by SDS PAGE and the results are shown in Figure 3.

Results and Discussion

The successful cultivation of mealworm larvae using a simple set of plastic growth containers at room temperature, enabled the class to perform a set of simple biological observations of the various stages of the insect Life Cycle. It also paved the way for the use of the larvae for preliminary work to begin to investigate the mealworm proteome. Conditions were obtained that enabled proteins to be extracted rapidly for analysis of SDS PAGE.

“The proteome is the entire set of proteins expressed by a genome, cell, tissue or organism at a certain time.

More specifically, it is the set of expressed proteins in a given type of cell or organism, at a given time, under defined conditions. The term is a portmanteau of proteins and genome.”

— Wikipedia

— Wikipedia

The flow chart in Figure 2 summarizes the final, successful method used for the success of the extraction of proteins. It was clear that the use of a glass homogenizer was the most promising and reproducible method, with samples maintained on ice being preferred, in order to guarantee results were repeatable.

ROYAL SOCIETY SPECIAL I ISSUE 17 Tenebrio I WWW.YSJOURNAL.COM Molitor

63 Larvae

INVESTIGATION The Darkling Beetle for Exploring “–omic” Science.

Future plans

The next phase of work, which has almost been completed is the use of liquid chromatography and mass spectrometry to begin to catalogue the proteome of the mealworm at different stages in development. This work will go hand in hand with our current collaboration with the University of Liverpool Genome Centre, to obtain the sequence of the mealworm genome.

Figure 2 Flow diagram for the extraction of mealworm, larval proteins:

Single, frozen larvae 

Figure 1 Panel a, mealworm larvae

Glass, 5ml dounce homogenizer (ice cold)  Slowly add 4ml ice cold phosphate buffered saline  Homogenise on ice, 10 minutes  Divide the suspension between 4 eppendorf tubes 

Panel b, adult beetles

Centrifuge top speed bench top microcentrifuge  Remove soluble proteins in the supernatant  Analyse 10μl by SDS PAGE

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The Darkling Beetle for Exploring “–omic” Science. INVESTIGATION Figure 3 1

2

3

4

5

SDS Polyacrylamide Gel analysis of larval proteins extracted manually.

Molecular weight markers are shown in Lanes 1 and 3 (the 4th band down is 70 000Da). Lane 2 is an extraction in 1M NaCl (PBS) and the fractions in lanes 4 and 5 are from different student groups in PBS.

Tenebrio Molitor

Acknowledgements

This work represents the first example of the introduction of a novel model organism into a school, laying the foundation for genome and proteome analysis by students. Participants: Jack Webster, students from year 10 at Liverpool Life Sciences UTC (the UK’s first school specialising in Sciences & Healthcare), David Hornby (on secondment from the University of Sheffield, Department of Molecular Biology and Biotechnology), Michael Kusimo and Jonathan Moore from Innovation Laboratories.

Author Liverpool Life Sciences UTC, Liverpool This project was run across the class of year 10 students at the Life Sciences UTC. Authors: Sasha Jordan,

Phoebe Dowling, Mikolaj Gajewski, Laura O’Reilly, Caitlyn Evans, Lois O’Brien, Marcus Page-Jones, Bethany Farr, Antonia Davis, Liam Hales, Mia Mulholland, Courtney Moran, Hannah Dooley, Molly Harris, Mollie Orme, Tamzin Pearce, Gabrielle Singleton, Charlotte Stevens-Cuthbert, Ellie Clifton, Ellie Clitheroe, Eleanor Curtis, Kyle Denton, Elle Harris, Aidan Hunt, Denise Preston, Lauren Scott, Stephanie Stazicker, Beth Tucker, Conor Young, Shane Clelland, Ellie Kavanagh, Millie Keegan, Marcus Kennedy, Callum Lamb, Amy Mccabe, Armand Morvai, Charlie Pendleton-Mcgee, Chloe Pisani, Jack Stewart, Dara Beesley, Jayne France, Kieran Harris, Claudia French, Ben Brownrigg, Tyra Calland-Green, Katie Foster, Abigail Gainford, Lauren Mason, Chelsea-Leigh Taaffe, Simon Dale, Radhika Joshi, Louis Keegan, Samuel Lamb, Emily Montgomery-Smith, Callum Morgan, Antonia Peters, Megan Robertson, Elizabeth Spellman, Rolake Akinyande, Callum Bishop, Chloe BlackwellTomlinson, Emily Challinor, Rhys Elgumati, Gabrielle French, Jesse Gitau, Rosie Hughes, Elisha Mcnulty, Jordan Ray-Roberts, Amelia Sampson, Christine Skillen, Asa Taylor, Jerome Thompson, Michelle van Zyl ROYAL SOCIETY SPECIAL I ISSUE 17 I WWW.YSJOURNAL.COM

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