Scientia - Issue 1

Scientia.

Abingdon School's Science Publication www.abingdon.org.uk

BRIDGING THE GAP THE CONNECTION BETWEEN PURE MATHEMATICS AND BRIDGES

+ REFUELLING ABINGDON

WINNER OF GAP 2014

THE SILVER SCREEN

THE ACCURACY OF CHEMISTRY IN MOVIES

DIDCOT - A GREENER FUTURE?

A GAP 2014 ENTRY

THE HUMAN MICROBIOME

ALL YOUR CRACKS ARE FILLED WITH MICROBES

Volume 1 March 2015

Scientia.

Letter from the editor

MAGAZINE

MARCH ISSUE 1

Welcome to the first issue of Scientia, an Abingdon School science publication.

FOUNDER

HENRY NUNNEY ____ CHIEF EDITOR

ANTHONY CHANG ____ DESIGN EDITORS

ASTEN YEO ANTHONY CHANG ____ CONTRIBUTORS

JAMES BRUCE JEREMY CHAN ANTHONY CHANG AGAMEMNON CRUMPTON GEORGE DYKE HENRY HART HENRY NUNNEY ALASTAIR SMITH AL TAYLOR GEORGE WILDER JUSTIN WILSON ARCHIE WIMBORNE PETER WANG ____ SPECIAL THANKS

RICHARD FISHER OLIVER LOMAX |

CONTENTS PAGE CREDITS “DIDCOT A / NIGHT” COURTESY OF HOWARD STANBURY IS LICENCED UNDER CC BY-NC-SA 2.0 “FLAME” COURTESY OF CAROLINA BIOLOGICAL SUPPLY COMPANY IS LICENCED UNDER CC BY-NC-ND 2.0 “DISASTER MOVIE” COURTESY OF [ANDREASS] IS LICENCED UNDER CC BY 2.0

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here is no denying that science is an integral part of our lives. From the cereal you eat for breakfast every morning to the very roads you walk on to get to school, everything we come across in our lives span across different branches of science.

The word “science” has its roots from the Latin word “scientia”, which translates into “knowledge” in English. The scientific method is now the modern, conventional way of acquiring new knowledge by academics and scientists. As students studying A-Level science, we hope to convey the knowledge that we have gained from learning more about our interests, and, by doing so, to help discover your own interest in this extremely broad and diverse subject.

To achieve this, we tried our very best to include a range of different topics of science. Our feature article, as shown on the front cover, introduces the application of pure maths in bridge construction, with another short piece delving deep into the possibility of tunneling the Atlantic. We also discuss the realism of chemistry in movies, as well as alternative energy sources for our school. In addition, we examine the age-old question of whether we can live forever, (literally) sleep on the research for why we desperately need snoozing time, and look into the organisms that live inside our bodies. To top it all off, there are some bits and bobs of colder branches of science that we have attempted to investigate too, such as the mysterious world of noetic science.

So really, we do offer some sort of variety of texts.

My heartfelt thanks to Mr Richard Fisher and Mr Oliver Lomax for dealing with the administrative and logistical nightmares, to Henry Nunney who pulled everyone together to form this amazing team, to Asten Yeo who has worked tirelessly with me on the layout, and to everyone who contributed in this publication. Without these people, Scientia would not have been possible.

If you feel like contributing to our publication, whether it is through writing an article, being an editor, or having some design input, please contact any member of our team.

And without further ado, please enjoy our first issue of Scientia.

“STAPHYLOCOCCUS AUREUS BACTERIA” COURTESY OF NIAID IS LICENCED UNDER CC BY 2.0

Anthony Chang Chief Editor

CONTENTS REFUELLING ABINGDON

by Alastair Smith and Al Taylor

2

ROBERT BUNSEN

by Henry Nunney

6

DIDCOT - A GREENER FUTURE?

by Anthony Chang and Jeremy Chan

7

BRIDGE MATHEMATICS

by Henry Hart

12

THE SILVER SCREEN

by Agamemnon Crumpton

16

NOETIC SCIENCE

by Jeremy Chan

20

TUNNELING THE ATLANTIC

by James Bruce

24

LIVING TO 1000

by Archie Wimborne

26

LITERATURE AND ENGLISH IN SCIENCE

by George Wilder

32

MR MIDDLETON'S MEGA MINDBENDER

33

THE HUMAN MICROBIOME

by Justin Wilson

34

WHY DO WE SLEEP?

by George Dyke

38

ROBERT BUNSEN

DIDCOT A GREENER FUTURE?

THE SILVER SCREEN

THE HUMAN MICROBIOME

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“MOVIE THEATRE” COURTESY OF ROEY AHRAM IS LICENCED UNDER CC BY-NC-ND 2.0

REFUELLING ABINGDON Al and Alastair tell us about the technology and possible benefits of using renewable fuels in our community

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ossil fuels will run out. There is no escaping it. In 2012, the world produced 35 billion tonnes of CO2, an average of 5 tonnes per capita (that is roughly 5000 m3 of CO2 per person, per annum) and we have reached, in total, 515 billion of the 800 billion tonnes of emissions needed to raise the average global temperature by 2 degrees Celsius.

In other words, we have just ten years left to make a difference. This paints an incredibly terrifying picture of the future, presenting a compelling argument for the need to curb our energy demands and to find new ways of producing energy sustainably. In this report we shall explore the production and use of potential future fuel candidates, both in a global and local setting.

When discussion comes to alternative fuels, there are three main ideas: ethanol, biodiesel, and hydrogen fuel cells.

ETHANOL

Ethanol is the fuel most people will think of when “biofuel” is mentioned. It is

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produced through either biological or non-biological methods, typical examples of which are as such: Live Fermentation. For production by this method, sugarcane, or other sugar- or starch-rich crops are grown, then processed with enzymes and other catalysts to become a ‘soup’ of simple sugars. Yeast is added to this, which uses the enzyme zymase to anaerobically convert sugars into ethanol and carbon dioxide.

C6H12O6 2CH3COOH + 2CO2 There are several benefits to this technique: the reaction occurs at a low temperature: zymase hits peak activity around 40°C so very little energy needs to be expended to keep the reaction going. Often in industrial plants, energy is expended to keep the reactor cool.

On the other hand, the process is not continuous, and needs to be run in batches, with the maximum yield at only around 14%. This is because a greater concentration of alcohol causes zymase

to denature, hence there needs to be additional processing to extract the alcohol from the resulting mixture, and to recycle unused sugar back into the start of the process.

The low (51%) atom economy of the reaction is got around by using carbon dioxide to carbonate drinks, but carbon dioxide is produced nonetheless.

Another important issue is of “fuel versus food”, that is, in many countries it would be more profitable to grow crops for the production of fuels than food for feeding the local populace. Thus this endangers local and, ultimately, global food supplies.

Another widely used way of producing ethanol is through the hydration of ethene using a phosphoric acid catalyst.

Here, a mixture of steam and ethene is heated with a phosphoric acid to around 300°C. The process is continuous, produces a 95% yield and high atom economy. The main drawbacks are that the process requires high temperatures, and therefore has a high energy demand; and ethene, the only main production

TRANSESTERIFICATION

DESIGN CREDIT: PETER WANG

Scientia. method of which is the reverse of this reaction, or from crude oil.

CH2CH2 + H2O CH3CH2OH Ethanol can be used as a combustible fuel, much in the same way as petrol or diesel, although a major drawback is that ethanol is not as dense; nor does it store as much energy as current fuels.

Hence more ethanol needs to be burned to produce the same amount of energy as either fuel. Also, at low temperatures (ten degrees Celsius or lower), not enough of the fuel can be vaporised for combustion.

This is due to hydrogen bonding between ethanol molecules requiring more energy to be broken than the van der Waal’s forces in typical hydrocarbons. For these reasons, and because ethanol improves the combustion of petrol, fuel ethanol is used mostly as a petrol additive in the USA and Europe, and often makes up around 25% of petrol burned in cars today.

BIODIESEL

Another “traditional” biofuel is biodiesel.

Biodiesel is a fuel produced from almost any fatty acid, lipid or fat through the process of trans-esterification.

Fats typically consist of three fatty acid chains (carboxylic acids) bonded to a glycerol molecule (three carbon atoms in a chain, with an –OH group on each carbon) with ester bonds. In trans-esterification, the fatty acids are removed and bonded to a simple alcohol (such as methanol, which can be produced from steam and carbon dioxide). This leaves a mixture of ester compounds, where one side of the molecule is larger than the other. The carboxylic acid part of the molecule has simply changed its alcohol group in the ester bond.

Since it is mostly a single, long hydrocarbon chain, biodiesel has many properties similar to regular, petroleum diesel, though it has a few notable differences.

For example, biodiesel is slightly denser (0.88 g cm-3 as opposed to 0.85 g cm-3), and

the point at which it vaporises in order to become combustible is more than 130°C as opposed to 64°C for petroleum diesel. On the other hand, biodiesel is more lubricating than regular diesel, and contains virtually no sulphur, since it is derived entirely from products containing just carbon, hydrogen, and oxygen.

This is important because regular fuels, as long as they have come from crude oil, are likely to contain sulphur, which when burned becomes sulphur dioxide, a precursor to acid rain.

Biodiesel can be used blended with ordinary diesel, in a similar way to ethanol and petrol, since biodiesel concentrations of up to 20% require no engine modifications. As stated, biodiesel can be made from almost any fatty acids, lipids, or fats, though the length of fatty acid chains will affect the properties of the resulting fuel. As a result, biodiesel production is an effective way of recycling waste oil, such as from deep-frying equipment. It can also be produced from specialist crops, such as rapeseed, though this has similar ethical implica-

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THE HYDROGEN FUEL CELL

DESIGN CREDIT: PETER WANG

Scientia. tions to growing feedstock for ethanol production. Two to five percent blends of biodiesel tend to be cheaper than regular diesel as well, by roughly 12 cents per gallon in the USA.

HYDROGEN FUEL CELLS

Hydrogen is often talked of as a possible future fuel source. It can either be burned in a modified internal combustion engine, in a similar fashion to petroleum (indeed, the first ever internal combustion engine was powered by hydrogen), or used to generate electricity in a hydrogen fuel cell.

When burning hydrogen in an internal combustion engine, there are a few differences to petroleum-based internal combustion engines. Firstly, the internal parts, such as valves, need to be effective for gas opposed to liquids. Hydrogen also requires far less energy to ignite.

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That is because the reaction has a lower activation energy (only a single H-H bond needs to be broken per molecule in order for the reaction to occur, while in petroleum fuels, many C-H and C-C bonds need to be broken).

To generate electricity via a fuel cell, oxygen and hydrogen enter the cell at opposite sides, often separated by a membrane or electrolyte. The actual electric current is created by the following ionisation reactions, where the electrons are exchanged between the reactions via a metal wire and the electrolyte, and so an electric current is formed.

Anode: H2 2H+ + 2eCathode: O2 + 4e+ 2O2The major drawback of using hydrogen as a fuel is its production. Hydrogen can be produced by the steam reforming of methane, with the following equation:

CH4 + H2O CO + 3H2 This naturally requires methane, or natural gas. Hydrogen can also be produced through the electrolysis of water, or dilute sulphuric acid, which in a sense is the reverse of the fuel cell reaction.

Hence hydrogen could be considered as a way of storing electrical energy produced in nuclear or other “green� power stations in a more effective way than using rechargeable batteries (which are in essence the same thing, but using other compounds to store potential energy.).

Another large drawback of using hydrogen as a fuel is storage. Being a gas at room temperature, hydrogen is not very dense, and so to store enough hydrogen to travel a reasonable distance would require a huge tank, or very high pressures. Alternatives include metal hydrides, which store hydrogen in a solid

“AGRILIFE-ALGAE-FACILITYCRANE” COURTESY OF TEXAS A&M AGRILIFE IS LICENCED UNDER CC BY-NC-ND 2.0

Algae can be grown to be used as a biofuel, shown here in an agricultural facility in Texas

ionic compound as opposed to a gas, and release it at low pressure, or complex nanotube-based structures, yet this remains a prominent research field.

There are other less well-known or traditional methods of producing and using alternative fuels. For example there is the production of biodiesel using algae.

This method involves growing colonies of fast-growing algae, which are harvested, their lipids removed and converted into biodiesel. In strong sunlight, the algae can grow up to 50 g per square metre per day, using 90% of the CO2 that it is exposed to. Furthermore, by genetically engineering algae, lipase enzymes in the algae (enzymes which cause the breakdown of fats and oils) can be switched off or even removed, thus causing a greater build-up of lipids within the algal cells. In addition, more genetic engineering could allow the algae to grow in inhospitable conditions, such as in varying pH and temperature levels. If such algae could be grown cheaply, the effects would be incredibly beneficial for both the production of fuels and plastics.

How feasible is the use of these fuels?

Well, it is unlikely that we would be able to requisition the transformation of Upper Field from a cricket pitch to a sugar cane field for the production of bio-ethanol! In the wider Abingdon

community though, there is the possibility to use empty fields in the area around town to grow crops for the production of biodiesel. Furthermore, the town council could run initiatives in the area, such as buying waste food oil from appliances at local restaurants to be used for the production of biodiesel.

The power station in Didcot raises the possibility of using electric vehicles or hydrogen fuel cells. It is widely known that electric vehicles can be far more efficient than regular cars and vans (some are reported to run at the equivalent of 500 miles per gallon), although they tend to have very short ranges (50 – 100 miles at best). Hence the benefits would probably be limited to only a few people outside large cities such as London, so would probably not be much use in the area local to Abingdon.

Another possibility would be the heating of school buildings. Our sports centre is very efficient in terms of energy use for heating, and so, probably, will our new science centre. It turns out that with a simple nozzle change, a home boiler can burn biodiesel rather than normal heating oil. Such an initiative would make the heating of our buildings carbon neutral.

Continuing with the school theme, rather than implementing a full scale

change to alternative fuel use, it could be worth using small scale production to educate the pupils as to the need to find viable alternatives to fossil fuel, and may even inspire them to develop them in the future. One such initiative would be to place algae growers, vertical tubes containing algae and water, around the school, and periodically extracting the algae for harvest, where it could be processed using one of the many kits on the market.

For the future, perhaps wider education and research into the use of alternative fuels, along with nationwide, regional, and local enticement for businesses to start using or producing alternative fuels may be a better solution than an immediate transition to technologies which are not ready, though time is running out.

REFERENCES: http://edgar.jrc.ec.europa.eu/news_docs/pbl-2013-trends-in-global-co2emissions-2013-report-1148.pdf http://www.carbonbrief.org/blog/2013/11/2013-emissions-edge-theworld-closer-to-2-degrees/ http://www.cefs.ncsu.edu/whatwedo/energy/biodieselpembroke.pdf http://www.afdc.energy.gov/pdfs/afpr_jul_07.pdf http://www.theregister.co.uk/2012/08/17/safe_hydrogen_storage/ http://www.freestateprojects.org/files/biodiesel+algae/Biodiesel%20 from%20algae%20-%20USDOD%20report.pdf http://www.sciencedaily.com/releases/2013/11/131120192147.htm

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Robert Bunsen Henry Nunney delves into the life of the Man behind the Burner

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his pioneer of the periodic table deserves special praise, since his infamous burner has enabled more inane stunts than any other lab equipment in history. Disappointingly, German scientist Robert Bunsen didn’t actually invent ‘his’ burner; he only improved the design and popularised it in the mid-1800s. Even without the Bunsen burner, he managed to pack plenty of danger and destruction into his life.

Bunsen’s first love was arsenic.

Although element thirty-three has had quite a reputation since ancient times (Roman assassins used to smear it on figs), few law-abiding chemists knew much about arsenic before Bunsen started sloshing it about in test tubes.

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He worked primarily with arsenic-based cacodyls, chemicals whose name is based on the Greek word for ‘putrid.’ Cacodyls smelled so foul, Bunsen said, they made him hallucinate, ‘producing instantaneous tingling of the hands and feet, even giddiness and insensibility.’ His tongue became ‘covered with a black coating.’

Perhaps from self-interest, he soon developed what’s still the best antidote to arsenic poisoning, hydrated iron oxide, a chemical related to rust that ‘clamps’ onto arsenic in the blood and drags it out. Still, he couldn’t shield himself from every danger. The careless explosion of a glass beaker of arsenic nearly blew out his right eye and left him half blind for the last sixty years of his life.

After the accident, Bunsen put

arsenic aside and indulged his passion for natural explosions. Bunsen loved anything that spewed from the ground, and for several years he investigated geysers and volcanoes by hand-collecting their vapours and boiling liquids. He jury-rigged a model geyser in his laboratory and discovered how geysers built up pressure and blow. Bunsen settled back into chemistry at the University of Heidelberg in the 1850s and soon ensured himself scientific immortality by inventing the spectroscope, which uses light to study elements. Each element on the periodic table produces sharp, narrow bands of coloured light when heated. Hydrogen, for example, always emits one red, one yellowish green, one baby blue and one indigo band. If you heat some mystery substance it emits those specific lines, you can bet it contains hydrogen. This was a powerful breakthrough, the first way to peer inside exotic components without boiling them down or disintegrating them with acid.

To build the first spectroscope, Bunsen and a student mounted a prism inside a discarded cigar box, to keep out stray light, and attached two broken off eyepieces from telescopes to peer inside, like a diorama. The only thing limiting spectroscopy at that point was getting flames hot enough to entice the elements.

So Bunsen duly invented the device that made him a hero to everyone who ever melted a ruler or set a pencil on fire. He took a local technician’s primitive gas burner and added a valve to adjust the oxygen flow. (Remember the knob on the bottom of a Bunsen burner? That’s it.)

As a result, the burner’s flame improved from an inefficient, crackling orange to the ‘roaring’ blue one you see today.

Bunsen’s work helped the periodic table develop rapidly. Although he was opposed to the idea of classing elements by their spectra, other scientists had fewer qualms, and the spectroscope immediately began identifying new elements. Just as important, it helped sort through claims of spurious elements by finding old elements in disguise of unknown substances. This new method of reliable identification got chemists a long way toward the ultimate goal of understanding matter on a deeper level.

DIDCOT:

A GREENER FUTURE? Anthony Chang and Jeremy Chan explore ideas for reusing the Didcot Power Station site

Green Chemistry – “The invention, design, and application of chemical products and processes to reduce or eliminate the use and generation of hazardous substances.”

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he Didcot Power Station stands, in southern Oxfordshire, as one of the main power sources in the UK. Consisting of a combined coal and oil power plant and a natural gas power plant, namely Didcot A and B respectively, the complex supplies directly to the National Grid and meets the needs of over 3 million people by generating a combined 3360 MW of electricity.

Didcot A, a coal-and-gas fired power station, was completed in 1968 with up to 2400 workers

employed at peak times. Its 200-metre tall chimney, six hyperbolic cooling towers, and four 500 MW generators are able to produce enough energy for more than twice the population of the entire county. The station burnt mostly pulverised coal (fine-powdered coal dust) as well as fired by natural gas, being the first power station in the UK to have this function.

On the other hand, Didcot B is a very efficient, gas-fired power station that began operation in 1997, using the latest technology of combined cycle

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gas turbines to produce electricity. This improves the net efficiency of the system from approximately 35% to 60%, as the wasted heat in a single cycle steam plant is extracted and recycled into the second turbine, resulting in a lower operating cost with an improved efficiency.

The combustion of fossil fuels to generate electricity produces waste gases. The emission of carbon dioxide into the atmosphere produces carbonic acid in the following chemical equations: CO2 + H2O → H2CO3 H2CO3 + H2O ⇌ H3O+ + CO32Sulphur deposits in coal becomes oxidised into sulphur dioxide or undergo further oxidation into sulfur trioxide.

These reacts with moisture in the atmosphere to form sulphurous and sulphuric acid respectively: SO2 + H2O → H2SO3 SO3 + H2O → H2SO4 H2SO3 + H2O ⇌ H3O+ + HSO3HSO3- + H2O ⇌ H3O+ + SO32(Note: Sulphuric acid H2SO4 dissocatiates in the same fashion.)

Nitrogen, at the high temperatures in the combustion chamber, reacts with oxygen

to form nitrogen oxides, which would again react with moisture in the air to form nitrous and nitric acid: 2NO2 + H2O → HNO2 + HNO3 HNO2 → NO + ·OH NO2 + ·OH → HNO3 HNO3 + H2O ⇌ H3O+ + NO3As shown in all the equations above, H3O+ ions, or simply H+ ions, are dissociated from their respective anions and thus making rain acidic. This has a major negative impact on aquatic life, plants, and limestone structures.

Radical chemistry plays a major role in our atmosphere. Radicals keep our ozone layer in check at a constant level to absorb harmful radiation. However, too many of them will catalyse the decomposition of ozone and result in ozone depletion. ·NO + O3 → NO2 + O2 NO2 + O → ·NO + O2 By preventing the above reactions from happening, it will certainly give the Earth a chance to recover from years of industrialisation and pollution.

INTRODUCTION Because of the traditional coal-firing method of producing power in Didcot A, a Flue Gas Desulphurisation equipment[1] was recommended to be installed, but was instead turned down; this has subsequently led to the decommissioning process. By removing sulphur from the waste gases of coal combustion, it would reduce the influence in the formation of acid rain and air particulates, thus having a lesser impact on the environment.

However, the decision for not upgrading meant that there was a limit of 20, 000 operating hours before closure.

As a result, the site area of Didcot A will be freed for development projects, with more than 580,000 m2 of land released by 2018 after demolition processes.

In light of this availability, we have researched and come up with ways of reusing the land for alternative, greener energy sources, or as processing plants for the county region, while discussing the chemistry behind such methods.

We have come up with ideas and they basically fall into 2 main groups: Energy Production and Waste Treatment.

ENERGY PRODUCTION Hydrogen Fuel Plant:

“URANIUM LEAK” COURTESY OF CLEMENT127 IS LICENCED UNDER CC BY-NC-ND 2.0

Hydrogen has been said for many years as the fuel of the future. Fuel cells have tremendous usage, whether in transport or in commercial buildings, or even in Terminators[2]. A particular type of hydrogen fuel cell, known as the Proton Exchange Membrane Fuel Cell (PEMFC), which features a low operation temperature at around 50-100°C and a polymer electrolyte membrane. When fed with hydrogen gas, the anode turns hydrogen molecules into protons and electrons.

The protons then pass through the membrane to the cathode, while electrons are forced to travel in an external circuit, thus creating an output current. At the cathode, oxygen is pumped to form water with the protons and electrons.

Anode: H2 → 2H+ + 2eCathode: ½ O2 + 2H+ → H2O

Radioactive waste is a major drawback from using nuclear fuel sources

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(+1.229V produced in this reaction)

This reaction has a maximum theoretical efficiency of 83% at room temperature, and the addition of platinum catalyses the reaction[3]. Since platinum is very expensive, scientists are looking for ways of using nanoparticles or different structures to increase catalytic activity.

“CELLS WITH NUCLEI IN BLUE, ENERGY FACTORIES IN GREEN AND THE ACTIN CYTOSKELETON IN RED” COURTESY OF ZEISS MICROSCOPY IS LICENCED UNDER CC BY-NC-ND 2.0

Hydrogen Storage:

Storing hydrogen gas is dangerous as it combusts and explodes very easily. One way to avoid this danger is to use metal hydrides, which can release hydrogen when heated to about 120-200°C. However, this is not a very efficient way of storage as they are only capable of storing a low weight percentage of hydrogen.

Another way is to use metal ammine complexes. These compounds contain ammonia ligands bound to a central metal atom, forming coordinate complexes.

Each ammonia group can give 3 hydrogen atoms (i.e. 1.5 moles of hydrogen) when decomposed using heat[4], and to form a complex, ammonia is passed over an anhydrous salt MX with heat, where M is a metal cation and X is an anion.

A major advantage of using metal ammine complexes over metal hydrides is that the former can give 1.5 moles of hydrogen per ammine ligand, which increases the percentage weight of hydrogen to around 9-10%. This in turn increases the amount of energy produced per mole of ammine complex compared to a hydride, but with current technology, there is less energy output than input from the compound. Perhaps, in the near future, there may be highly efficient catalysts available requiring a lower energy input.

Microbial Fuel Plant:

Mitochondria[5] can be said as the power source in all cells. By converting fatty acids and pyruvate[6], the digested products from sugar and fats, into adenosine triphosphate (ATP), a minute current is generated by the electron flow in the electron transport chain in the organelles[7]. By harnessing this current from immobilised mitochondria, the electrical energy can be extracted through an electrolyte to the anode when the substrate is completely oxidised to carbon dioxide.

An example of a eukaryotic cell, of which a minute current can be harnessed from the mitochondria

This is a completely renewable energy source, and is stable at room temperature and neutral pH for up to 60 days, meaning that replacing mitochondria frequently would be an issue in terms of workforce and costs. Fuel, as mentioned above, can be as simple as glucose or using digested food waste. The main limiting factor of this type of fuel cell is that the density of mitochondria on the electrode is not high enough, a problem resulting in a low output energy density. This is an area currently under active research by bioengineers. Nonetheless, to completely utilise the Didcot site as a mitochondria fuel plant would supply a significant amount of electricity to the National Grid.

Prokaryotic[8] fuel cells work very similarly to mitochondria fuel cells.

Although they do not have mitochondria, they have an electron transport system in the cytoplasm that does the same processes as in the eukaryotic electron transport chain.

WASTE TREATMENT Biofuels:

By redeveloping the site into a treatment plant, biofuels can be made by fermenting organic waste using bacteria/microorganisms under anaerobic conditions.

C6H12O6 → C2H5OH + 2CO2 Methane can also be produced by bacteria by the following mechanism: C6H12O6 + 4H2O → 2CH3COOH + 2H2CO3 + 4H2 CH3COOH → CH4 + CO2

The problem with using this method is that the climate in the UK is too cold for optimum enzyme activity. Perhaps it could be solved by using a temperature-controlled environment, but that needs to be accounted for in the energy produced.

Waste Gasification:

A substitute way of making fuel is to make it without combustion, using any carbon-containing compounds as feedstock.

Firstly, the biomass is dehydrated at around 100°C, and then heated to 200300°C where pyrolysis[9] occurs. Volatiles, such as hydrogen and methane, are released, as well as char (composed mainly of carbon). Some volatiles and some char may react with oxygen / steam in the air to as they are exothermic reactions: C + O2 → CO2 CO2 + H2O → CO + H2 CO + H2O → CO2 + H2

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An abandoned gas works facility

"At this stage, technological challenges are the main limiting factor behind greater output of energy."

The water-gas shift reaction[10] in the gasifier balances the amount of CO, CO2, H2O and H2 produced.

A major advantage of gasification over incineration is that it is much cheaper and more efficient. However, it is challenged by its large energy consumption balancing out the efficiency, as well as using large amounts of pure oxygen.

Plasma Gasification:

This is similar to traditional gasification, although an inert gas torch is used to raise the temperature to extremes (ranging from 2200 to 13900°C). At such heated conditions, molecules are broken

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“GAS WORKS TOWER” COURTESY OF BARON REZNIK IS LICENCED UNDER CC BY-NC-SA 2.0

into their individual atoms in gas state by a process called plasma pyrolysis, where the resultant mixture of gases can be used as fuel. Catalysts are used to increase reaction rates as well.

However, plasma gasification suffers from the same drawbacks as its traditional counterpart: the energy input is way higher than energy output from the chemical energy in the fuel gas. The initial investment will need to be high as well. Nonetheless this is one of the safer ways to destroy medical waste, such as needles, without any hazardous waste emitted. The alloys in the slag can be extracted and reused too.

Nuclear Power Plant and Waste Treatment Plant:

Nuclear fission is a very efficient way of producing energy, by firing neutrons at uranium atoms to start a chain reaction.

With an efficiency rate of around 92%, nuclear fission provides an exothermic reaction that heats up water to drive a turbine to generate electricity.

However, nuclear waste is a very difficult substance to process because of the long half-life of 235U and its radioactivity.

This meant that the used fuel has to be very well-kept to prevent leakage, as any spillages would be extremely harmful[11].

In order to be more sustainable, it would be sensible to try to reuse the nuclear waste and turn it into something useful, rather than burying it deep underground. Nuclear reprocessing can be done to chemically separate and recover fissionable radioactive metals from nuclear waste. This sounds awfully like nuclear weapons production, but setting aside the extraction of plutonium (and selling it to Syrian rebels), we will need to extract as much usable fuel as possible from the radioactive sources to reduce waste produced.

One way is to recycle processed fuel into MOX (Mixed Oxide) nuclear fuel[12] for thermal reactors. Though this method is only economical when radioactive fuel prices are high, it can be done to all actinides and could potentially increase the energy extracted from natural uranium by around 60 times! That is 3.5 x 1015 Joules of energy generated, equivalent to powering the entire United States of America for about 2.5 hours with only 1 kilogram of fuel!

These figures look promising, and reprocessing does reduce the volume of high radioactivity waste, but does not reduce the actual dose of radiation or heat generation, and hence there will still be a need for disposal.

Another way of reprocessing is PUREX[13]. It was originally invented as part of the Manhattan Project before becoming the standard method for chemically reprocessing nuclear materials.

The chemical process is as follows: Firstly the irradiated fuel is dissolved in a solution of nitric acid (conc. 7 mol dm-3), and any insoluble solids are filtered so not to interfere with the extraction process. A hydrocarbon solvent composed of 30% tributyl phosphate is mixed intensely with actinide-nitric acid solution, which separates the uranium and plutonium nitrates from actinide nitrates solution. Plutonium can then be separated from the solution by adding ferrous sulphamate solution, which selectively reduces plutonium to 3+, while uranium is extracted by backextraction into dilute nitric acid (conc.

0.2 mol dm-3).

PUREX allows the reuse of irradiated nuclear fuels after reprocessing, which increases the renewability and sustainability of nuclear power by successfully reducing waste. However, in light of recent political instability and tension in some parts of the world, this method is unlikely to be successfully developed in Didcot.

A less useful way of processing nuclear waste is to purify the radioactive water. Since the water in nuclear reactors contains radioactive contaminants such as toxic salts, heavy metals and radioactive fallout[14], filtration and distillation can remove such contaminants. They will of course need to be disposed of in a safe manner.

CONCLUSION Through this project, we have researched on and certainly learnt more about the various ways of producing energy greenly, in addition to greener treatment plants. Although it is quite clear that most of these methods are either improbable or impractical, such as nuclear reprocessing, we solely believe that the ideas that we have explored will in theory make Didcot a greener place. At this stage, technological challenges are the main limiting factor behind greater output of energy. Perhaps, in the near future, these ideas will become more viable and practical through leaps in the development of newer technology, which will eventually give benefit to our school and the surrounding areas as a source of energy from green chemistry.

CREDITS/REFERENCES: Dr. Leo Dudin Dr. Rebecca Howe Mr. Richard Fisher Mr. Simon James Mr. Ben Simmons Mr. Oliver Lomax John Wiejak’s Presentation on Metal Ammine complexes from Symposium 2013 kawaiihannah@deviantArt MindMeister Prezi ChemWiki www.chemicalformula.org http://dcwww.camd.dtu.dk/Nabiit/Metal%20ammine%20complexes%20for%20 hydrogen% 20storage.pdf http://en.wikipedia.org/wiki/Hydrogen http://en.wikipedia.org/wiki/Metal_ammine_complex http://en.wikipedia.org/wiki/Hydroxyl_radical http://en.wikipedia.org/wiki/Fuel_cell http://en.wikipedia.org/wiki/Proton_exchange_membrane_fuel_cell http://en.wikipedia.org/wiki/Ozone http://books.google.co.uk/books?id=5qWjAgAAQBAJ&pg=PA547&lpg=PA547&dq=metal+ammines&source=bl&ots=3k7zv8qwG6&sig=HZhAxMhNdOtBN18jgDolSIUrnNY&hl=en&sa=X &ei=JCIqU8T5Meqh0QWt7IBI&ved=0CD0Q6AEwAQ#v=onepage&q=metal%20ammines&f=f alse http://pubs.rsc.org/en/content/articlepdf/2011/cp/c0cp01362e http://www.rsc.org/chemistryworld/News/2010/August/27081001.asp http://uk.answers.yahoo.com/question/index?qid=20100527064643AA46dIu http://en.wikipedia.org/wiki/Citric_acid_cycle http://en.wikipedia.org/wiki/Pyrolysis http://en.wikipedia.org/wiki/Gasification http://en.wikipedia.org/wiki/PUREX http://en.wikipedia.org/wiki/Radioactive_waste http://freeenergynews.com/Directory/NuclearRemediation/Vesperman/ http://en.wikipedia.org/wiki/Water-gas_shift_reaction http://en.wikipedia.org/wiki/Nuclear_power http://en.wikipedia.org/wiki/Nuclear_reprocessing http://en.wikipedia.org/wiki/Ion_exchange http://en.wikipedia.org/wiki/PUREX http://chemwiki.ucdavis.edu/Physical_Chemistry/Nuclear_Chemistry/ Radioactivity/How_to _purify_radioactive_materials http://en.wikipedia.org/wiki/MOX_fuel Google

APPENDIX: [1]: Flue Gas Desulphurisation – Removal of sulphur dioxide in waste gases produced in power plants by reacting with metal hydroxides/carbonates to form sulphites or sulphates, for example: CaCO3 + SO2 → CaSO3 + CO2 [2]: Terminators – According to the movie franchise Terminator, Arnold Schwarzenegger’s character is a cyborg powered by two hydrogen fuel cells capable of producing a mushroom cloud when detonated.

[3]: Hydrogen fuel cell - Energy calculations: Energy = Voltage x Charge Energy = 1.229 x (2 x 1.6 x 10-19 x 6.02 x 1023) Energy = 192.6 kJ mol-1 [4]: Decomposition of ammonia: NH3 → 1 ½ H2 + ½ N2 [5]: Mitochondria - Membrane-bound organelles found in cells with nucleus (eukaryotes)

[6]: Pyruvate – A substance produced from the breakdown of glucose; 1 molecule of glucose forms 2 molecules of pyruvate. Structural formula is CH3COCOO-.

[10]: Water-gas shift reaction: The dynamic equilibrium of the reversible equation CO + H2O ⇌ CO2 + H2

[7]: Conversion of pyruvate into ATP in glycolysis process: Glucose 2(Pyruvate) + 2(ATP) + 2(NADH) Pyruvate Acetyl-CoA + NADH Acetyl-CoA 2(ATP) + 3(NADH) + FADH Electron Transport Chain (ETC): NADH 3(ATP) FADH 2(ATP Glycolysis of 1 molecule of glucose produces a maximum of 38 ATP. In the ETC, NADH/FADH molecules release electrons that are passed onwards by electron carriers with continuously lower energy levels.

This produces a minute current and therefore can be harnessed.

[11]: Interesting fact: Contrary to common belief, coal workers have a higher chance of getting cancer from mildly radioactive materials in ash than nuclear power station workers! This illustrates how safe nuclear power plants are, when there are no accidents happening...

[8]: Prokaryotic cells - Cells without a nucleus

[14]: Radioactive fallout: Since water itself cannot be radioactive, the radioactive components/ contaminants are referred to as radioactive fallout.

[9]: Pyrolysis – The thermal decomposition of a compound with the absence of oxygen

[12]: MOX / Mixed Oxide Fuel: A nuclear fuel that contains more than one oxide of fissionable material, usually consisting of plutonium blended with natural, reprocessed or depleted uranium.

[13]: PUREX: Plutonium Uranium Redox Extraction

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BRIDGE MATHEMATICS Henry Hart talks about the application of pure mathematics on bridge construction

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W

hen we think of pure maths, we think of results and functions that can be used on arbitrary expressions or equations but without much purpose or use, like determining the speed of a ball etc. Purpose is usually found in applied mathematics (hence the name) and pure mathematics is often given the underwhelming description of ‘interesting’.

In this article, I hope to show how bridges, as everyday structures, not

only connect landmasses but also bridge the void between pure and applied mathematics. If we consider a suspension bridge, the most efficient bridge type in terms of load per unit mass of construction materials, the most striking feature is the suspended curved cable, which looks like a parabola (!). Curves are of course heavily indicative of pure mathematics and we shall now dive into the mathematics of the cable and the internal and external forces on it.

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Before a suspension bridge can be completed, towers must be built and a cable hung and finally the deck is installed. In the case of the incredible Akashi-Kaikyo Bridge, a guide cable is hung over the towers so the main cables can be driven across.

Main questions include what length of cable is needed? And will anything happen to the cables when the deck is installed? Only mathematics can answer these questions accurately enough for such a large project.

What mathematics shall we use? Well, to discover the length of a curve, consider the following diagram:

To find the arc length f(x) between α and β, we first propose that γμ is an arbitrary segment of the arc αβ.

So now we need to determine the equation for a hanging cable: for this we need to return to the 17th century when Jacob Bernoulli issued a challenge to brother Johann Bernoulli, the teacher of Euler (perhaps the greatest mathematician of all time); Christiaan Huygens; and Gottfried Leibniz to derive the equation of a hanging cable. And they did indeed derive it as a catenary:

Cosh is the so-called hyperbolic cosine function because cosh, sinh and tanh all behave similarly to cos, sin and tan.

Without derivation, one would think that a hanging cable is exponential when one thinks about the forces on the cable: Tension always runs along the axis of a cable, so this asks how the force can change as shown in the diagram. If we perform a thought experiment where we hang a cable in zero gravity and apply a tension at both ends, we would find that the cable becomes a line. Thus we arrive at the answer that at every point tension changes due to the vector subtraction of cable weight:

Given that: ψ ≤ θ ≤ ψ + δψ, then: secψ < secθ < sec(ψ+δψ).

And as limγμ 0 γμ , then ψ = θ.

Using the identity sec2α ≡ tan2α + 1,

From above, we can use the equation

This arrangement suggests that the gradient changes with reference to f(x), which is the form of an exponential.

So what is the equation of the temporarily deckless Akashi Bridge, for example? We know that:

giving us:

Where f(x) is the formula of the curve, and α and β are the positions of the towers.

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Where x = 995.5 when y = 217.08 due to the height of the towers above the deck being 217.08m and the main span being 1991m (interestingly this was 1990m before the Kobe earthquake opened up a 1m wide fault in the Akashi strait, of which the bridge survived because of its huge dampers).

So:

so:

This is an iterative formula, so starting with: α = 2317.92 The iterations are 2317.919006, 2317.918516... and after very very many iterations, α = 2317.9180408801410483837582...

So we will use this value. Now we can work out the length of the cable needed for hanging:

When you ignore cable extension, this means the cable needs to be shorter to maintain the same depth, so the engineers will have to modify the length of the cable so that when hanging freely it does not reach its full depth. This is to ensure that it can extend when load is borne and can sink due to the changing of the shape. We can confirm that the parabola should be shorter by showing that the parabola deck and towers draw an area of:

Whereas the catenary draws a smaller area of:

Areac = 143189m2 So, as promised, it is reasonable to assume a loaded bridge is a parabola because it will be much closer to a parabola than a catenary. The shapes are so similar that the actual equation and the parabolic equation are practically the same.

Which seems about right for a 1991m bridge.

Now what happens when we place the deck on the hanging cables? The shape of a cable changes from a catenary to a parabola when a deck is placed on the cables and the cables have insignificant weight compared to the deck, which we shall for now assume and I shall later show is reasonable. A parabola has the equation y = βx2 and this will allow an easy calculation of β, unlike for the catenary and an exact value too! y = 217.08 when x = 995.5, so We can then say that:

As we can see here in these representations of the two curves, the black and red lines are fairly similar. It is therefore understandable that Galileo thought a chain hung in the shape of a parabola but certainly not acceptable for the precise construction of a bridge.

In this very applied field of bridge engineering, we have used supposedly very pure mathematics such as integration, differentiation, exponentials, Euler’s constant, imaginary numbers and hyperbolic trigonometric functions to model the shape of a bridge.

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“MOVIE THEATRE” COURTESY OF ROEY AHRAM IS LICENCED UNDER CC BY-NC-ND 2.0

THE

5

SILVER SCREEN

myths debunked by science

Aggy Crumpton reports on the accuracy of how chemistry is portrayed in movies

by Henry nunney

Superfoods prevent cancer Blueberries, beetroot, broccoli, garlic, green tea... the list goes on. Despite thousands of websites claiming otherwise, there is no such thing as a superfood. It is a marketing term used to sell products and has no scientific basis.

We’ve made no progress in fighting cancer This simply is not true. Thanks to advances in research, survival from cancer has doubled in the UK over the past 40 years. Death rates from it have fallen by 10% over the past decade alone. In fact, half of all patients now survive for at least 10 years.

Genetically modified crops create super-insects and super-weeds If farmers rely too heavily on Bt or glyphosate, then pesticide resistance is inevitable. It is an increasing problem that could lead to the return of harsher chemicals. The solution is to practise integrated pest management, which includes crop rotations.

Coffee is unhealthy and should be avoided Coffee has long been considered unhealthy, mainly because of the caffeine. However, most of the studies actually show that coffee has powerful health benefits. This may be due to the fact that coffee is the biggest source of antioxidants in the Western diet, outranking both fruits and vegetables combined. Drinkers have a much lower risk of depression, type 2 diabetes, Alzheimer’s and Parkinson’s, and some studies even show that they live longer than people who don’t drink coffee.

Saturated Fat raises LDL cholesterol in the blood, increasing risk of heart attacks Several massive review studies have recently shown that saturated fat is NOT linked to an increased risk of death from heart disease or stroke. The truth is that saturated fats raise HDL (the “good”) cholesterol and change the LDL particles from small to large LDL, which is linked to reduced risk of heart disease. For most people, eating reasonable amounts of saturated fat is perfectly and healthy.

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F

ilms show us the strange and wonderful, and they use this to create intrigue and entertainment so that we, as the audience, watch the films. This often results in people asking – “well, is that possible” or “can we actually do that?” I am going to be investigating just that, exploring the chemistry of films and evaluating the truth behind them. I will be doing this over a sample of 10 films and taking the chemistry out of them and scrutinizing it. I predict that there will be a lot of over-exaggeration as films want to show the fanciful and the impossible, since this is appealing to us as an audience.

I also predict (and hope) that as the budget increases, the accuracy of the chemistry (and physics) should increase proportionally as they have more money to spend on the research; however I feel this might not true as the budget might have been spent on other areas instead. Moreover, I think that movies will have become more realistic as we come forward in time, as I feel that audiences nowadays are a lot less tolerant with blatant impossibilities.

THE MUMMY

In the film The Mummy, salt acid is used in traps to stop people from entering

"AUDIENCES NOWADAYS ARE A LOT LESS TOLERANT WITH BLATANT IMPOSSIBILITIES." tombs by burning people’s faces and killing them. This acid would need to be stable for thousands of years, not evaporate and be extremely concentrated to kill people.

Salt acid is immediately an incorrect chemical term as salt is the product of an acid by definition. It is not known if the ancient Egyptian civilization at 2500 BC had acids, but it is a possibility they used green vitriol (green hydrated iron (II) sulphate) and collected the acidic vapor in a process first described by Vannoccio Biringuccio (1480-1539). Green vitriol is found amongst gold ores that were used by the ancient Egyptians in death masks.

Stomach acids of animals could be used but are unlikely to be of the concentration required. The possibility of storing strong acid could be in glass bottles but it would be difficult to ensure that no

evaporation took place over thousands of years. Also, since the pyramids and tombs are made from limestone, embedding a strong acid seems unlikely as it would destroy the building itself. The scene is theoretically possible but is extremely unlikely due to the complexity of the procedure.

CHARLIE AND THE CHOCOLATE FACTORY

In the film Charlie and the Chocolate Factory, green flames are seen as chocolate and sweet wrappers are thrown into fire. This usually indicates the presence of copper ions in flame tests.

When an element is given a lot of energy (e.g. through heat in a flame), it will cause the excitation of electrons to higher energy states (in the case of Bunsen flames ionising the electrons).

These electrons must then fall back down to their original sates and they release energy as they do so. This will emit a photon of a specific frequency and hence a unique colour. The other component of the colour of a flame is soot, which contributes to black body radiation (the radiation of energy from “black” objects when they are heated), causing the red and orange parts of the flame. This is interesting as dyes don’t contain copper ions, but instead could contain sodium or iron ions resulting in yellow and gold flame test results. This is not consistent with the film.

However, boron also produces a green flame result and there are some boron containing dyes, which are boron-phenylpyrrin dyes. They are currently under research by the Beijing Key Laboratory for Science.

high crystallinity, bonded together by amorphous linkages comprised of mainly glycine. The mixture gives it a combination of great strength as well as elasticity. Spider silk does still have the same breaking stress, though it is as high as as high alloy steel of 1850 MPa2.

This means that for Spiderman to have silk that is stronger than a climbing rope in strength, it would only have to be 1.5 mm in radius. This shows an underestimation the films have of the strength of spider silk; it would also be extremely lightweight: a kilometer of this thickness of spider silk would weigh 15.4 grams (which will take 12000 N, a massive overestimation of the force that is actually needed)! There are issues with the fact that the spider silk undergoes super-contraction when exposed to water, shrinking by 50% of its original length[1], which would not be good.

Spiderman uses spider webs to put on his wound, quite sensible as it contains vitamin K, which helps to clot blood as well as being an antiseptic.

A problem with Spiderman is the sheer amount of silk that would be

required, since in the film they took silk directly from spiders. This is incredibly impractical as there would be no way of regulating the type of silk produced, in addition to the inadequate thickness. A more realistic way of obtaining spider silk is to make it artificially, which has been done in real life by Nexia Biotechnologies dubbed as ‘Biosteel’.

This is made by genetically modified goats that secrete the silk into their milk in liquid form (spider silk is a liquid till it is spun). The silk is then extracted and made into microfibers to be used later.

‘Biosteel’ is 7 to 10 times stronger than steel if compared at the same weight, and can be stretched up to 20 times at its unaltered size without losing its strength properties. It also has very high resistance to extreme temperatures, not losing any of its properties between -20 and 330 degrees Celsius[1,2]. Spiderman may have also been missing a trick as spider webs would make excellent bulletproof armour, since it is light and flexible and is 5 times tougher than Kevlar.

“CANTILEVER” COURTESY OF ROB FRANKSDAD IS LICENCED UNDER CC BY-NC-SA 2.0

SPIDERMAN

We have seen the amazing properties of spiders’ silk when Spiderman swings around New York. In Spiderman his silk was used to swing on, so he would want some stretch in the silk. However if he were using capture spiral silk, which has more amorphous linkages and can stretch up to five times its relaxed length, it would be like being on a bungee rope. Spider silk is a protein chain made up of primarily glycine and alanine. This mixture of amino acids tends to form beta-pleated sheets with

Spider silk

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“1967 MUSTANG SHELBY GT 500 NOS BUTTON” COURTESY OF POE TATUM IS LICENCED UNDER CC BY-NC-ND 2.0

"THE IS REFERENCING TO N20, A NONTOXIC, FAIRLY STABLE MOLECULE."

Popularised in movies such as Gone in 60 Seconds, nitrous boosts have become a staple in action films.

MISSION IMPOSSIBLE 3

In Mission Impossible 3, a villain escapes from an armored truck using an orange foam, which causes the steel plating to become brittle and able to shatter. In theory this is completely plausible as metals (especially iron and steel) become very brittle at low temperatures. The orange foam may have super-cooled the steel to be able to shatter it. However, the thickness of the metal plating on an armored truck combined with the amount of cooling needed to get all of the metal at a temperature well below -150°C makes the scene unrealistic. There would also have to be a much larger force than just a sledgehammer’s worth to be able to shatter the steel plating that thick.

Overall I think the idea to cool the metal and shatter it is a good idea – there are still logistical concerns: ideally you would need a battering ram and a large quantity of liquid nitrogen, but it would be a safe way to extract the prisoner. My idea would just be to shatter the lock on the door or the hinges with liquid nitrogen,

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which is much easier to do and fits better within the timescale.

THE FAST AND THE FURIOUS

In The Fast and the Furious, nitrous oxide is used in quarter mile drag races to increase car performance. This is referencing to N2O, a nontoxic, fairly stable molecule. This is an accurate bit of chemistry and it works because nitrous oxide will decompose at high temperatures (at 300°C+)[3] into oxygen and nitrogen gas. This creates a mixture of 33% oxygen, which is an increase of over 50% in oxygen to be combusted compared to 21% oxygen in air. The nitrous oxide, or NOS, is stored as a liquid, so when it is injected into the inlet manifold (the place where the fuel and air are supplied to the engine in the right stoichiometric ratios), the liquid expands and cools the gases coming in, meaning that there is an increased density. Hence even more oxygen can be supplied to the engine.

Because of this, NOS systems have

to change the amount of fuel that is supplied to the engine to account for the increased oxygen. This means that there is more fuel reacting, thus a higher pressure is produced to drive the pistons at a much higher temperature (the decomposition of nitrogen oxide to its components is exothermic). This can cause some serious problems because the engine is not designed for the increased temperature and pressure, leading to piston rings being melted (as referenced in the film) as well as the possibility of the pistons breaking through the metal casing. The film seems to portray NOS as a very short burst; however, from what is quoted by a company’s “15- 18 full quarter mile passes”[4] (NY-Trex), it shows a massive underestimation of NOS in the film. The NOS is also quoted by the same website using their generic NOS kit (in the film it was probably custom made with the recommended increased fuel injectors and aluminum pistons) you could get “10 – 15 MPH in a quarter mile”[4], which is normal.

This shows the increase in speed due to nitrous in the movie is very realistic, if not an underestimation. Some different sources quote you can get a 3000HP increase[3], yet this however is in modified drag racers which solely run on NOS. The chemistry of nitrous systems is correct and the film surprisingly underestimates possible performance.

A KNIGHT'S TALE

In A Knight’s Tale, the blacksmith produces armour which is supposedly thinner but stronger than normal steel. The strength of steel means the steel is harder and hence is brittle. Steel can be hardened in a number of ways, first and foremost is by ‘work-hardening’, which is rolling the steel or beating it with a hammer.

The steel structure is deformed causing dislocations, and it is the dislocated parts

of the metal crystals that define the shape of the metal. Materials that are strong would not have dislocations that move, so to allow this to happen, more dislocations should be created. The strongest steel possible is a 100% martensite steel mix, which requires heating the steel to 1200°C with 2% carbon[5] (obtained from iron carbon phase diagram). The steel should be left to quenched to cool it rapidly, which produces very pure martensite steel – it is extremely austenitic and strong, but brittle. This creates problems with the idea of using thinner and stronger steel for armour for jousting, as it is really important that if you do get struck the armour could absorb some of the impact by bending as opposed to just fracturing; this steel is too brittle for the job so it would not be advantageous.

[1] Wikipedia, (2014) Spider silk [Online] Available at http://en.wikipedia.org/wiki/Spider_silk (Accessed 11 August 2014) [2] Harris, T. (2014) HowStuffWorks “Spider Silk [Online] HowStuffWorks Available at http://animals.howstuffworks. com/arachnids/spider3.htm (Accessed 11 August 2014) [3] Wikipedia, (2014) Nitrous oxide engine [Online] Available at http://en.wikipedia.org/wiki/Nitrous_oxide_engine (Accessed 11 August 2014) [4] Designengineering.com, (2014) Frequently Asked Questions - Nitrous Oxide | Exhaust Header Wrap and Thermal Performance Products | Design Engineering, Inc. [Online] Available at http://www.designengineering.com/nytrex/ faq (Accessed 11 August 2014) [5] MSE 300 Materials Laboratory Procedures (2014) 1st edn. (Tennessee, Dept. of Materials Science and Engineering) [Online] Available at http://web.utk.edu/~prack/MSE%20300/FeC.pdf (Accessed 11 August 2014)

TO CONCLUDE, there is no real correlation between the amount of money spent on the budget and the accuracy of the film, as deemed by me using my rating out of 10. However, my predictions look like it was proved slightly false by the slight negative correlation between rating and year, so there is a slight decrease in the standard of accuracy of chemistry over the years. This is probably due to the different genres of film where people would not really analyse the films very much.

I found that there was actually very good chemistry and theoretical physics shown by big famous films, which has evidently been well-researched (Avatar and Star Wars). I was also surprised by the underestimation in The Fast and the Furious and Spiderman, as I would have expected more over-exaggeration. There is a certain amount of pointlessness with this whole idea as I am scrutinising a small area of films that defies the science we know very thoroughly.

REFERENCES: Avatar Wiki, (2014) Unobtanium [Online] Available at http://james-camerons- avatar.wikia.com/wiki/Unobtanium (Accessed 11 August 2014) BBC Science, (2014) Frozen body: Can we return from the dead? [Online] Available at http://www.bbc.co.uk/science/0/23695785 (Accessed 11 August 2014) Bhadeshia, H. (2014) Materials Science & Metallurgy, 1st edn. [Online] Available at http://www.msm.cam.ac.uk/phase-trans/2002/martensite.html (Accessed 11 August 2014) Cavemanchemistry.com, (2014) Caveman to Chemist Projects: Acids [Online] Available at http://cavemanchemistry.com/oldcave/projects/acid/ (Accessed 11 August 2014) Competitionplus.com, (2014) Busting a few Myths about Nitrous Oxide [Online] Available at http://www.competitionplus.com/05_20_2004/n20_myths.html (Accessed 11 August 2014) Gallegos, J. (2014) Rocket Belts of Tecnologia Aeroespacial Mexicana [Online] Tecaeromex.com Available at http://www.tecaeromex.com/ingles/RB-i.htm (Accessed 11 August 2014) Geom.uiuc.edu, (2014) Translational Symmetry Student Page [Online] Available at http://www.geom.uiuc.edu/~lori/symmetry/translate.html (Accessed 11 August 2014) HowStuffWorks, (2014) HowStuffWorks "How does nitrous oxide help an engine perform better?" [Online] Available at http://auto.howstuffworks.com/question259.htm (Accessed 11 August 2014) Infoplease.com, (2014) Sulfuric acid: History of Sulfuric Acid | Infoplease.com [Online] Available at 1-http://www.infoplease.com/encyclopedia/science/sulfuric-acid-history- sulfuric-acid.html (Accessed 11 August 2014) Isracast.com, (2014) IsraCast: Like a fish - underwater breathing system [Online] Available at http://www.isracast.com/article.aspx?id=63 (Accessed 11 August 2014) Ncbi.nlm.nih.gov, (2014) Boron-phenylpyrrin dyes: facile synthesis, structure... [Chemistry. 2013] - PubMed - NCBI [Online] Available at http://www.ncbi.nlm.nih.gov/pubmed/23633394 (Accessed 11 August 2014) Newton.dep.anl.gov, (2014) Cold Metal Shattering [Online] Available at http://www.newton.dep.anl.gov/askasci/eng99/eng99249.htm (Accessed 11 August 2014) Scienceline.ucsb.edu, (2014) UCSB Science Line sqtest [Online] Available at http://scienceline.ucsb.edu/getkey.php?key=3239 (Accessed 11 August 2014) Scientificamerican.com, (2014) Why is spider silk so strong? [Online] Available at http://www.scientificamerican.com/article/why-is-spider-silk-so-str/ (Accessed 11 August 2014) Stronger, M. and Capudean, B. (2003) Making steels stronger - thefabricator.com [Online] Available at http://www.thefabricator.com/article/metalsmaterials/making-steels-stronger (Accessed 11 August 2014) Substech.com, (2014) Iron-carbon phase diagram [SubsTech] [Online] Available at http://www.substech.com/dokuwiki/doku.php?id=iron-carbon_phase_diagram (Accessed 11 August 2014) Watson, S. (2014) HowStuffWorks "How Cryonics Works" [Online] HowStuffWorks Available at http://science.howstuffworks.com/life/genetic/cryonics2.htm (Accessed 11 August 2014) Webexhibits.org, (2014) Flame tests | Causes of Color [Online] Available at http://www.webexhibits.org/causesofcolor/3BA.html (Accessed 11 August 2014) Wikipedia, (2014) Antimatter [Online] Available at http://en.wikipedia.org/wiki/Antimatter (Accessed 11 August 2014) Wikipedia, (2014) Antimatter rocket [Online] Available at http://en.wikipedia.org/wiki/Antimatter_rocket (Accessed 11 August 2014) Wikipedia, (2014) Black-body radiation [Online] Available at http://en.wikipedia.org/wiki/Black-body_radiation (Accessed 11 August 2014) Wikipedia, (2014) Cryonics [Online] Available at http://en.wikipedia.org/wiki/Cryonics#Revival (Accessed 11 August 2014) Wikipedia, (2014) Flame [Online] Available at http://en.wikipedia.org/wiki/Flame#Flame_color (Accessed 11 August 2014) Wikipedia, (2014) Fluoroantimonic acid [Online] Available at http://en.wikipedia.org/wiki/Fluoroantimonic_acid (Accessed 11 August 2014) Wikipedia, (2014) Iron (II) sulfate [Online] Available at http://en.wikipedia.org/wiki/Iron_(II)_sulfate (Accessed 11 August 2014) Wikipedia, (2014) Jet pack. [Online] Available at http://en.wikipedia.org/wiki/Jet_pack (Accessed 11 August 2014) Wikipedia, (2014) Thermite [Online] Available at http://en.wikipedia.org/wiki/Thermite (Accessed 11 August 2014) Wookieepedia, (2014) Carbonite [Online] Available at http://starwars.wikia.com/wiki/Carbonite (Accessed 11 August 2014) Wookieepedia, (2014) Miniature vaporator/water converter [Online] Available at http://starwars.wikia.com/wiki/Miniature_vaporator/water_converter (Accessed 11 August 2014) World-mysteries.com, (2014) Lights of the Pharaohs: the Electric Lights in Egypt? Guest article by Frank D?rnenburg [Online] Available at http://www.world- mysteries.com/sar_lights_fd1.htm (Accessed 11 August 2014)

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NOETIC SCIENCE

REALITY OR PRETENSE?

A graph showing interest over time of the term ‘Noetic Science.’

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SOURCE: GOOGLE TREN

DS, 7 FEBURARY 2014.

WEB. 7 FEBURARY 2014 .

Jeremy Chan brings us closer to the field of noetic science

2010

“How beliefs, thoughts, and intentions affect the physical world.”

- The Institute of Noetic Sciences

N

oetic science, not to be confused with noetic philosophy, has not been more popular ever since the release of Dan Brown’s novel The Lost Symbol in 2009 (I can’t blame you if you don’t read much), as the book mentioned scientific experiments on the metaphysics – abstract philosophical concepts.

The book certainly evoked the curiosity of many readers, some amazed by the potential of this ill-understood branch of science, and that the impossible, such as telekinesis and extra-sensory perception, could be made reality; however many skeptics believe that all this noetic science business is just nothing but a work of fiction, the excrement of B. Taurus and nothing more than a theme just to link science and religion together in the novel.

The Lost Symbol mentioned a man at the verge of death who was willing to donate his body to an experiment. The man was placed on an ultrasensitive scale in a sealed tube so nothing can enter or leave. At the exact moment of his death, the mass of the man decreased by a thousandth of a gram. One of the main characters, Katherine Solomon, who was conducting the experiment, deduced that the mass loss was due to the soul/spirit of the man leaving the body.

Dr. Duncan MacDougall, a doctor in Massachusetts who conducted research on attempting to weigh the human soul, had perhaps inspired Dan Brown to include this experiment in his novel. In 1901, MacDougall did a similar experiment by weighing his patients as they passed away.

Even though he had claimed that mass loss could be observed, there was a variation of mass loss amongst the subjects. The doctor also conducted the same experiment on fifteen dogs and observed no change in mass at death; hence he proved that dogs, unlike humans, have no souls. MacDougall did not seem to make any breakthroughs after 1911

and died in the following year. In 2000, an Oregon Rancher, Lewis Hollander Jr., conducted the same experiments on animals (eight sheep, three lambs and a goat). According to MacDougall’s research there should not be any mass lost, yet his results showed a gain in mass. Despite MacDougall’s efforts, his results were never successfully reproduced and hence are scientifically meaningless.

A Japanese author and entrepreneur, Dr. Masaru Emoto, believes that human conscience is able to manipulate the molecular structure of water. He claims that pure water or water that has positive thoughts directed to it would form a uniform and “beautiful” snowflake if frozen; while polluted water or negative feelings would create a deformed and “ugly” one.

Emoto conducted a noetic experiment involving a group of about two thousand in Tokyo. They were instructed to focus positive intentions towards water samples inside an electromagnetically shielded room in California. According to his reports, the results of the experiment were consistent and suggest that human thoughts could really alter physical reality.

Physicists criticised the idea since the very concept violates the laws of physics. Lebbrecht’s morphology diagram of ice crystal formation shows how ice crystal form into different structures depending on the temperature and the humidity of the air the water is in. His procedure did not control these two main factors – which was probably the contributing factor towards the change in the structure of the ice crystals. According to Emoto, his ice crystals started to form at -5°C. According to the morphology diagram, the crystals should be in the form of columns instead of plates, as shown in the photographs of Lebbrecht’s publications. Some suggest that Emoto might have excluded non-supportive data from his research.

Another famous experiment of Emoto was the ‘Rice Experiment’ – this requires three containers

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IT IS EXTREMELY DIFFICULT TO APPLY THE SCIENTIFIC METHOD OR THE BASIS OF MEDICAL AND BIOLOGICAL CONCEPTS ON SUCH POORLY DOCUMENTED NOTIONS of rice soaked in water. Something must be said to the rice containers every day for a month. The experimenter is required to say something positive to one of the rice containers (e.g. saying “thank you” or praying to it). The second rice container would be cursed at (e.g. saying “I hate you” or swearing at it).

The last one would be left as a control experiment.

According to Emoto’s results, the first container radiated a fine smell of rice wine fermenting; the rice in the second container turned black and reeked foully; finally the control experiment just turned moldy.

Many curious people over the world attempted the experiment, however their results were not as repeatable as they anticipated. Most experimenters ended up with three containers of moldy rice and a stinking room for a month. One suggested that the experiment contains many flaws – not having any controlled variables and operating on the smallest possible size. Furthermore, it was suggested that it was simply “a race to see which rice gets moldy first”.

Emoto was denounced for misleading the public with his claims, and for his experimental methods that were unable to investigate his claims properly.

As we look back into the past, people have practiced noetic principles on their own physical bodies via meditation for thousands of years. Eastern cultures within the spheres of influence of India and China have meditation practices involving the channeling of ‘life force’ or ‘vital energy’ (‘Prana’ if you are Indian, ‘Chi’ if you are Chinese, or ‘The Force’ if you are Jedi) through their bodies. Hindu concepts involve manipulating this ‘energy’ by unlocking chakras, or energy points, with immense amounts of concentration of the mind, while their Chinese counterparts focus on the concept of balancing the ‘energy’ using one’s internal alchemy. Ultimately, the goal is to achieve higher realms of awareness, unlocking one’s ‘true nature’ and enhanced performance. These practices were claimed to bring healing properties, with some people meditating as a form of alternative medication. Others may even apply these principles in martial arts like Kung Fu, Aikido, etc. However (surprise, surprise) current technology is unable to detect any of these ‘energies’.

Even though there is ongoing (barely funded) research, it is extremely difficult to apply the scien-

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tific method or the basis of medical and biological concepts on such poorly documented notions (but somehow they work – which is why they are still practised today). Yet despite how appealing the idea of noetic science is, many real scientists and skeptics have been heavily criticising it and calling it a form of pseudoscience because of large amounts of selection bias and methodological flaws. According to the Institute of Noetic Sciences, this field ”explores the ‘inner cosmos’ of the mind (consciousness, soul, spirit) and how it relates to the ‘outer cosmos’ of the physical world”. This definition is extremely similar to parapsychology – a branch of pseudoscience concerning the human mind to cause paranormal occurrences to happen. Like Emoto’s ice and rice experiments, parapsychology is notorious for its poor use of scientific method in investigation, often involving no or poor controls, small sample sizes, or even the consideration of using double-blind trials.

However, there are quite a few mainstream scientists who considered the idea of the mind directly affecting matter and proposed quite a few feasible theories that still going along the lines with the laws of physics, like “thought forms are simply another aspect of transmitted energy” or “an information transfer constantly carries on between living things”. Some even suggest it might be the bridge between classical physics, which we witness it taking action in our daily lives, and quantum physics, which occur in the subatomic level. After all, quantum entanglement does prove that there is a mesh in the universe that interlinks every single particle of matter, and string theory suggests matter and energy are vibrating, 1-dimensional strings.

But would it all turn out to be true? Or is it just a pile of made-up nonsense by fake scientists? We do not know yet, but I am sure there will be an answer in the future.

RESOURCES: Wikipedia http://www.snopes.com/religion/soulweight.asp http://themindunleashed.org/2014/01/scientific-proof-thoughts-intentions-can-alterphysical-world-around-us.html http://media.noetic.org/uploads/files/Double-blind_water.pdf http://www.ncbi.nlm.nih.gov/pubmed/16979104 http://www.creatingconsciously.com/ books/emotowaterbook.pdf http://organicuprising.com/the-rice-experiment/ https://www.youtube.com/watch?v=Ehlw-9PJkIE#t=16 https://www.youtube.com/watch?v=4sbzCaEsHfw http://sciencereporting.blogspot.co.uk/2012/02/how-to-design-rice-experiment.html http://is-masaru-emoto-for-real.com/ http://rationalwiki.org/wiki/Noetic_science http://www.huffingtonpost.com/ lynne-mctaggart/why-dan-browns-science-fi_b_325906.html

In 1988, John Chang, an Indonesian accupuncturist, claimed to have used Chi to ignite a piece of paper with his bare hands. This was documented by filmaking duo Lawrence and Lorne Blair, although skeptics insist that it was a carnival trick.

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CIVIL ENGINEERING:

TUNNELING THE ATLANTIC James Bruce discusses the problems of engineering a transatlantic tunnel

O

bviously, spanning the whole width of the Atlantic with an underwater tunnel would have a huge number of issues associated with it, and would it even be worth the money? Engineers have proposed various solutions to the problem but it is still very much a theoretical idea. Such a tunnel would cost upward of ÂŁ5 trillion and there are still limits on our knowledge of materials science; at the moment we may not even have access to the right tools for the job! However, if completed, it would be the greatest engineering wonder ever accomplished.

Deciding on the right depth would be a huge factor: if the tunnel ran too deep it would be under so much pressure from the water above that it would simply collapse, yet having it too high would interfere with shipping traffic. This would mean the only design possible is a suspended immersion tunnel.

Moreover, a tunnel contains large amounts of empty space, and hence the tunnel would have large buoyancy force acting upwards on it. This means it must be tethered down by strong cables.

These cables would also need to have enough give to allow the tunnel to survive impacts from ocean currents or even large sea currents.

Method of construction is also a new challenge to engineers, as immersed

tunnels have never been made to be suspended in water before. Assuming parts are manufactured beforehand and fitted at sea, transporting parts of the tunnel to be fitted in the middle of the Atlantic Ocean could be extremely dangerous, given the hazardous weather conditions.

Given that the areas of the bed of the Atlantic are extremely seismically active, further issues are presented: there would need to be constant monitoring of the whole length of the tunnel so that adjustments and/or repairs could be made.

One method would be to have seismic sensors that would trigger the cables attaching the tunnel to the bed to tighten in order to resist the shock. However, this will also mean that materials used are also going to need a certain amount of strength to resist the increased force when the cables are tightened, so material engineers will need to be employed to design materials with higher strengths and resist corrosion in salt water.

So many potential problems are associated with building a transatlantic tunnel. However, when we have made the right steps in the various fields of science, I believe it is well within the limits of what humans are capable of achieving and would be well worth an investment as it marks a huge step forward in engineering.

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{~} LIVING TO

1000 WILL IT EVER BE POSSIBLE?

Archie Wimborne looks into the possibility of living to 1000 years old

A

t 85, she decided to take up fencing; twenty years later she was still happily riding her bike. She made her first movie appearance at age 114 and decided to release her debut CD on her 121st birthday. Finally, aged 122, Jeanne Calment called it a day. She had the longest lifespan ever recorded. Born in 1875, she witnessed two world wars and 5 British monarchs (although she was French so wouldn’t care) before dying in 1997. A life that long is mind-boggling.

Having spent most her time in the twentieth century, Calment’s age could not be attributed to the standard of health care. On her 30th birthday, for example, gasoline was still being used to

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kill head lice. As a result, when queried on how to mirror her longevity, her advice was simply “always keep your smile”, backing up her age by suggesting that God had forgotten about her. It seems a life this long is down to luck of genetics more than anything else.

It is generally agreed that 122 years is a more than satisfactory time to spend on Earth - many would even hate to live that long. But is a world where Calment could be viewed as young ever possible?

Having been raised in a society where death is inevitable and unavoidable, the idea of eternal life is a fairytale - restricted to pop culture and myth for centuries.

Over 4000 years ago, in The Epic of

Gilgamesh, a Sumerian king seeks eternal life. And in the 1500s, Spanish explorer Ponce de Leon came to the Americas searching for the fountain of youth. Even today, ask most people about eternal life and they will instantly label it as fantasy.

Yet there are a select (but growing) few academics that don’t just believe eternal life will one day be possible - but that it will be so in our lifetime. In the words of futurist Ray Kurzweil: “I and many other scientists now believe that in around 20 years we will have the means to reprogram our bodies' stone-age software so we can halt, then reverse, ageing. Then nanotechnology will let us live for ever.”

“VANITAS II” COURTESY OF PATRICK RIGON IS LICENCED UNDER CC BY-NC 2.0

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“ There’s no evidence

that there’s a limit to human longevity

”

In order to achieve eternal life, ageing must be halted, and ideally, reversed.

Of course, there will always be certain uncontrollable causes of death - trauma, or a new tropical disease. Yet two thirds of deaths worldwide are attributed to old age, as high as 90% in industrialised countries. Prevent old age, and these billions of people may have lived for centuries - even millennia. And Miss Calment would still be alive today.

WHAT IS AGEING? From birth right up until death, our bodies are constantly changing, growing, and ageing. The signs of getting older are common knowledge: wrinkled, thin and inelastic skin; greying hair; deteriorating memory and immune systems, and a decline in muscle strength. They are things we see day-in, day-out in the elderly generation. It is a natural process that happens to everyone.

Sure, your lifestyle may affect the rate of ageing: it is generally agreed (and summed up in the German Dr. Huseland’s work On the Art of Prolonging Life, 1797) that by making wise food choices and monitoring portion sizes, drinking plenty of water, increasing physical activity (strength, flexibility, aerobic training along with your daily activities), and closely watching your posture, you can slow the ageing process. Add good

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care of your teeth; weekly bathing in lukewarm water with soap; good sleep; clean air; and being born to parents who themselves lived long lives, and Huseland proposed a human could live to 200 years.

Nowadays, whilst technically speaking there is no ‘biological limit’ on the human lifespan, (and everything is speculation), it is generally agreed Calment may have been pretty close to the maximum - especially without major scientific or medical intervention. Steven Austad from the University of Idaho sums up the guesswork pretty well: “There's no evidence that there's a limit to human longevity,” he says.

“Experts used to say that humans couldn't live past 110. When people blew past that age, they raised the number to 120. Then Jeanne Calment thumbed her nose at that stop sign. So why can't we go higher?”

WHY DO WE AGE? Ageing is an extremely complicated subject. After all, it seems strange that the Turritopsis nutricula, a jellyfish found in the Mediterranean sea, is able to revert its cells to their earliest form and grow anew (and therefore have infinite lives), whilst most jellyfish live less than a year; some only a few days. Between species, there is a massive variance in lifespan, and the reasons for these lifespans to end

“(ÓLEO/OIL - 120CM X 120CM)” COURTESY OF PATRICK RIGON IS LICENCED UNDER CC BY-NC-2.0

differ even more widely.

In humans, the ageing process is controlled largely by three main factors: oxidative stress, glycation, and telomere shortening. And in order for humans to live longer, all of these would have to be overcome.

OXIDATIVE STRESS Oxidative stress is damage to DNA, proteins, and lipids caused by oxidants, which are highly reactive substances containing oxygen. They are produced when we breathe, and also result from inflammation, infection, and consumption of alcohol and cigarettes. When oxidants react with certain molecules in the body, they release free radicals: atoms or groups of atoms with an odd number of electrons (unpaired electrons) - for example, superoxide (O2-). These free radicals can chemically interact with cell

components such as DNA, proteins or lipids and steal their electrons in order to become stabilised. This, in turn, destabilises the cell component molecules which then seek and steal an electron from another molecule, therefore triggering a large chain of free radical reactions.

This either kills the cell completely, or causes its DNA to change (and the cell to possibly mutate). It grows and reproduces abnormally and quickly. Before long, the body may become cancerous.

Fortunately, we are able to protect against this, by utilising â&#x20AC;&#x2DC;antioxidantsâ&#x20AC;&#x2122;.

Antioxidants are molecules present in cells that prevent these reactions, by donating an electron to the free radicals without destabilising themselves.

An imbalance between oxidants and antioxidants is the underlying basis of oxidative stress - something that becomes more and more prevalent as we

age. Over a lifetime this damage mounts up, eventually causing pathophysiological conditions in the body. These include neurodegenerative diseases such as Parkinson's and Alzheimer's, gene mutations and cancers, chronic fatigue syndrome, fragile X syndrome, heart and blood vessel disorders, atherosclerosis, heart failure, heart attack and inflammatory diseases.

How can it be beaten? Whilst changing your lifestyle to avoid taking in oxidants should have a positive affect (which Dr. Huseland unknowingly summed up earlier), studies show the benefits are minimal. Similarly whilst consuming antioxidants (vitamins A, C, E and β-carotene found in fruit and vegetables) to counteract the free radical damage should be beneficial, studies tend to show that antioxidant therapy has no effect and can even increase mortality. All

the same, recent tests where scientists exposed worms to two substances that neutralise oxidants increased their lifespan an average 44%. Unfortunately this method remains untested in humans. Since many different substances operate simultaneously in antioxidant defence, its complicated process may require more sophisticated approaches to determine if antioxidant therapy may benefit the ageing process - approaches which remain unknown.

GLYCATION Another factor in ageing is "glycation."

Again, it involves the degeneration of DNA, proteins, and lipids - but this time by glucose. This is due to the fact that when sugars react with amino acids, they form AGEs (Advanced Glycation Endproducts), which are extremely harmful. The process creates inflammation, which, having

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GGCTCGCTAATTCGC CCTTGGGTGTTTTGC TAGGCTAGCTGCGTG TG CTTGGTCTCTCGT activated your immune system, attract macrophages. It is their duty to respond to the AGES, possessing special receptors for them known as RAGEs (Receptor for Advanced Glycation Endproducts).

These RAGEs bind to the AGEs in your body and get rid of them. Unfortunately, this defensive process can also cause its fair share of damage. Inside your arteries, for example, the scar tissue created from this process is called plaque, which is linked to atherosclerosis and heart failure.

Furthermore, there is mounting evidence that AGEs may be implicated in the development of the chronic degenerative diseases associated with ageing, including cardiovascular disease, Alzheimer's, and diabetes mellitus.

How can it be beaten? Again, overcoming glycation does not promise immortality - without other anti-ageing procedures, it could only ever extend life by a few years. Still, in the lab, animals indicate that restricting calorie (and thus sugar) intake extends lifespan. These were subject to a complex interplay of genetics, nutrition and environmental factors, however, and hence may not be completely transferable to humans.

TELOMERE SHORTENING Inside the nucleus of a cell, our genes are arranged along twisted, double-stranded molecules of DNA called chromosomes. Telomeres reside at the end of the chromosome, also formed from DNA: repeating sequences of TTAGGG on one strand paired with AATCCC on the other strand. Similari-

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ties are often drawn between telomeres and the tip on the end of our shoelaces, because they keep chromosome ends from fraying and fusing together, which would destroy or scramble the genetic information of an organism.

Yet, each time a cell divides, the telomeres get shorter. This is due to the fact that during DNA transcription, there must be a space for short pieces of RNA at the ends of a strand. Therefore parts of the telomeres are replaced with RNA. To counter this, an enzyme named telomerase adds bases to the ends of telomeres. In young cells, telomerase keeps telomeres from wearing down too much. But as cells divide repeatedly, there is not enough telomerase, so the telomeres grow shorter and the cells age.

For example, in white blood cells, you have 8000 base pairs (as a newborn) in your telomeres, but this drops by between 30-200 with every division of the cell. This only allows for 50-70 divisions until the telomere becomes too short, becoming inactive, "senescent", or dead. This shortening process is associated with ageing, cancer, and a higher risk of death. In contrast, in the elderly a telomere starts out with as low as 1500 base pairs. Clearly, this allows for much fewer cell divisions before the DNA becomes senescent.

How can it be beaten? Telomerase is the key. In studies, mice, which had been genetically engineered to lack telomerase from birth, aged prematurely; but when supplied with the enzyme, they did not just seem to stop ageing,

but in fact appeared to become younger.

Shrivelled testes grew back to normal and the animals regained their fertility.

Other organs, such as the spleen, liver and intestines, recuperated from their degenerated state, and even their brains grew bigger. Dr. DePinho, one of the scientists performing the tests, was quoted to say: â&#x20AC;&#x153;It gives us a sense that there's a point of return for age-associated disorders. Drugs that ramp up telomerase activity are worth pursuing as a potential treatment for rare disorders characterized by premature ageing, and perhaps even for more common age-related conditions.â&#x20AC;?

We will have to wait and see whether telomerase can be used to such effect in humans.

The downside is that telomerase is often mutated in human cancers, and seems to help existing tumours grow faster. But scientists argue that telomerase should prevent healthy cells from becoming cancerous in the first place by preventing DNA damage.

ON THE SUBJECT OF LIVING FOREVER It seems that eternal life is still, at our current levels of technology, impossible.

In the years to come there will hopefully be many developments in anti-ageing procedures - such that the average human lifespan will continue to rise at its current rate. In the 1600s, it was as low as 30 - but by 2012, life expectancy in the West was reaching 80. There are no signs of it slowing down.

Even if it does one day become

CACTGTCGGG CACTAGCGTCAG “ Scientists argue that GGTCAAATATCG telomerase should TACTTCTCTCAG prevent healthy

“HEART CELLS” COURTESY OF ARBOREUS IS LICENCED UNDER CC BY-NC 2.0

cells from becoming cancerous

possible to eradicate all examples of death by natural causes, this in no way means everybody will live forever and ever. I am no philosopher, nor do I have the time to debate the pros and cons of eternal life, but I am sure many people would not want to live in a world where you cannot die.

The Earth is already struggling to accommodate its 7 or so billion inhabitants. If you were to remove all deaths from Earth, but keep all new births, the population would rise to around 10 billion by 2020. Clearly, at this rate, the Earth could not sustain the human race long enough to even find out if anyone is truly immortal.

And even in a hypothetical world where we somehow defeat over-population; whilst disease and ageing may be eradicated, evil and accident cannot. Say the chance of dying from an ‘unnatural cause’ (e.g. homicide, suicide, terrorism, trauma) each year is 0.005%. Sounds pretty low right? Well, the chance of dying unnaturally before you are 100 is 39.4%.

Before 200 is 63.3%. 500 is 92.8%, and less than 1 out of 100 would live to 1000 - past 5000 is almost statistically impossible.

Perhaps eternal life is better suited to fairy tales after all then.

”

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LITERATURE AND ENGLISH IN SCIENCE George Wilder studies the connections between language and science

D

ue to its existence as a humanities subject, the scientific study of English Literature is often thought to be rare, or even non-existent. Yet, the effect of literature has on both reader and writer is an area that has become far more intensely researched since the turn of the millennium. One example of this was research that investigated the many authors who have claimed that characters have the ability to actively disagree with the author.

The University of Oregon studied the phenomena from 2002 to 2003[1], where the common childhood psychological condition known as Illusion of Independent Agency (IIA) was observed to be commonplace in authors. The condition is commonly associated with the imaginary friends that children develop from the age of three onwards. However, out of 91 published authors 92% had experienced IIA during their writing, whereas most adults lose the condition during adolescence. This gives thought to the argument that once characters are formed in the mind of a writer, they are aware of change and able to resist it. Popular cases explored by Oregon University outside the sample included J.K Rowling’s encounters with Harry Potter after trying to change him into a female character and Sara Paratsky,

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who regularly had physical arguments with her characters. Writers from Jean Paul Satre to Quentin Tarantino have also reported these sorts of responses by characters, with E. M. Forster describing characters as “creations inside a creation that are often inharmonious towards it”.

In addition to psychiatric papers, studies have also been conducted using brain scans of readers. Studies in Spain recently commented on how describing something with a word that alludes to a human sense (e.g. leathery hands for touch) subconsciously activates the part of the reader’s brain that controls that sense. However, if the language used doesn’t indicate a sensually relatable experience, this area of the brain will remain inactive. Likewise, when describing actions such as running any particular focus on the body parts involved, like “he ran, his legs coursing away beneath him”, this will activate areas of the brain that control motor function in the legs. Similar tests have taken place in the field of neuro-cinematics, a branch of neuroscience that aims to find out what we enjoy about films and television in order to improve them.

Yet, the observation of brains in this field has not indicated a precise link despite numerous investigations (some of which can be found in the New Scientist health

pages). The ability of literature not just to describe an experience, but also to activate parts of the brain that relate to that experience, reflects how much thought must be given to every detail of the piece, as this will form a physically sensory experience as well as a mental one. Modern novelists, like Stephen King when writing “Under the Dome”, are able to combine these effects to deliver sensory impact by combining language that affects certain areas of the brain and alternating between them to deliver a piece of fiction that better relates to its genre.

The study of the effect of literature on our brains is a rapidly growing field as we try to unravel just how potent the impact can be. In the case of the first study, it was concluded that writers, by exposing themselves to the creation of characters, could cause them to empower the characters with a sense of psychosomatic free will. The second study is still undergoing as it tries to discover to what extent a piece of fiction can replicate a physical experience in the brain. Looking to the future, they will also try to discover what makes the brain so responsive to literature, and to what extent this can be used for educational and entertainment purposes.

1. When a moving car encounters a patch of ice the brakes are applied. Why is it desirable to keep the wheels rolling on the ice without locking up?

Static friction is greater than kinetic friction and there is static friction when cars wheels are rolling.

2. You are in a boat on a lake, in the boat there is a log that floats and in the lake there is an anchor. If you pull up the anchor and tie it to the log (so it would sink), would the lakeâ&#x20AC;&#x2122;s level rise, fall or stay the same?

It would rise as there is no change due to the anchor, but there is extra displacement from the log as it displaces its volume.

3. If a ball is rolling on a flat plane that never deforms, and the ball never deforms itself, can the ball roll forever? (Do not take air resistance into account in this model)

there all along anyway but are not so easy to break down, so they last longer.

5. The protons shown in green for 2,4-pentanedione (I) are roughly 1040 times more acidic than that of those on n-pentane (II). Why?

Because of the different resonance structures available to the (I) stabilising the anion.

6. Why do you feel dizzy when you spin?

The cochlea, in the ear, contains a liquid that moves when you do to tell your brain what position your body is in.

When you spin, the liquid also spins, but it takes time to stop after you do, so you continue to feel like youâ&#x20AC;&#x2122;re spinning until the liquid settles.

7. Why do cats always land on their feet?

MR MIDDLETON'S MEGA MINDBENDER Here are ten questions on different areas of science of varying difficulties. See if you can solve them all without peeking at the answers first...

Section written by Agamemnon Crumpton and Justin Wilson

adept brain. Another theory states that this is down to sexual selection as smarter individuals were more desirable, and hence were more likely to pass on their genes.

These are two of many theories.

it reacts with calcium in bones to form the stable and insoluble compound calcium fluoride.

By building a really tall tower, the moment of inertia can be increased, slowing down the rotation of the Earth.

It can be compared to an iceskater putting his/her arms out while spinning in order to slow the rotation.

Yes, because if you were to draw the force diagram, you must either create torque increasing the turning or increase velocity.

Cats have a unique skeletal structure, where the bones in their spine are very flexible and they do not have a collarbone.

This makes it easier for them to bend and rotate their bodies mid-air.

4. Why do leaves go red in autumn?

8. Why are human brains so large?

9. Why is hydrofluoric acid so dangerous even though it is a weak acid?

Chlorophyll is broken down in the winter. It reveals the yellow and orange pigments called carotenoids that are

Many theories exist.

One is that humans with larger brains were more able to plan ahead due to their more cognitively

HF, as a polar covalent molecule can diffuse through skin, and fluorine is very damaging to biological molecules and

10. How would you slow down the rotation of the Earth without any objects leaving it?

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THE HUMAN MICROBIOME Justin Wilson reveals to us the stuff that lives within us

W

e humans have always been concerned with our health, though we have not, until recently, been particularly good at determining what is important to it.

It turns out that the human microbiome is an important determinant of human health in many ways. For example, it can determine whether an individual will be allergic to a certain drug, a food substance or even dust.

Additionally, microbes in the intestines can help in the digestion of food (which can be beneficial and detrimental), influence behaviour and have an effect on the immune system.

WHAT IS THE HUMAN MICROBIOME? The human microbiome consists of all microorganisms in and on the human body, including bacteria, microeukaryotes, viruses and archaea. The most commonly studied microbiomes are that of the skin, intestines (fecal/gastrointestinal/gut), mouth (oral), and vagina.

It is important to note that each site on the human body has a characteristic set of microbes; therefore, if samples are taken from several body sites of several individuals, data from different body sites will tend to cluster together.

For example, the intestinal microbiome

is generally dominated by bacteria from phyla Firmicutes, Bacteroidetes and Actinobacteria. Fecal samples are typically analysed to look at the intestinal microbiome, due to the fact that to directly obtain a sample from the intestines would (obviously) require invasive surgery.

THE GASTROINTESTINAL MICROBIOME AND DISEASE The majority of microbes in any environment in or on the human body are what we would consider commensal, meaning that you receive no NET benefit of them being in or on you. Some others are sym-

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bionts, meaning that you receive a NET positive effect from the microbe. Finally, they can be pathogens, which have a NET negative effect on the human body. In every case, the microbe benefits from existing in the community that it does, due to the fact that the environment provides good conditions for growth.

A healthy human being will have relatively stable quantities of each type of microbe. However, when an individual is ill or if an individual has a chronic disease, the composition of the intestinal microbial community may change so that the pathobiont population is larger than normal, causing inflammation of the intestines. This can also cause the microbial diversity in the intestines to decrease, as other microbes cannot compete with these pathobionts.

This is worrying, as some microbes that are found to be associated with certain diseases, such as Crohn’s disease or ulcerative collitis, have been shown to carry out different functions in unwell people and healthy people, and this can be a contributing factor in the progression of the disease.

There is also increasing evidence that suggests some cancers are linked to bacterial agents. For example, Fusobacterium nucleatum has been linked to tumours of the large intestines in several different studies conducted independently. This anaerobe is present in low amounts in healthy intestinal tissue, but is present in high abundance in colonic tumours. Research is currently being done to investigate whether this bacterium causes tumour formation or whether they move to the tumour after it appears. F. nucleatum is, however, able to cause inflammation and induce the growth of cancerous lesions by interaction with human cells in the large intestines.

THE GASTROINTESTINAL MICROBIOME AND OBESITY The first study that linked the human microbiome to obesity involved leptin deficient mice, which cannot produce the hormone leptin (which induces the feeling of satiation). This results in the mice eating excessively until they become obese.

Analysis of fecal samples from these two different types of mice showed that the obese mice had broad, phylum-level changes in the composition of their intestinal microbial communities, showing an increased representation of Firmicutes and a decreased representation of Bacteroidetes.

As previously noted, one of the main benefits of having the intestinal microbiome is that they digest some molecules in food that we humans cannot, due to the fact that we do not possess the necessary enzymes to digest these molecules.

Hence, the microbes in the intestines are very useful in a Hunter-Gatherer society where food was scarce, as more energy could be ‘extracted’ from the same amount of food. However, this may have turned to become a disadvantage for some, as the microbes of an obese community possess a greater number of genes that code for enzymes that digest lipids and carbohydrates, hence meaning that a greater percentage of ingested foods are digested, meaning that the same food essentially has a higher calorific value for obese individuals than for lean individuals, making it harder for these obese individuals to lose weight.

Causation can be proved through the use of gnotobiotic mice, who are raised in microbe- free isolaters and are therefore not colonised by any microbes upon birth or during development. These mice can therefore be colonised by specific microbes decided by the experimenter, and research can be done on how this affects the body mass of the mouse. This can be done by fecal matter transplants, and showed that gnotobiotic mice who received transplants of samples from obese mice gained more weight at a faster rate than those who received samples from lean mice when food intake was controlled.

the cell-mediated response is against pathogens within the body’s cells and involves T-helper and T-killer cells that cause apoptosis (programmed cell death) of infected cells.

The intestinal microbiome is constantly interacting with the immune system, but the immune system must allow the microbes to exist by recognising that they are foreign but not pathogenic.

Hence, the gut microbiota is constantly monitored by the immune system through certain cells in the intestinal epithelium. They effectively ‘test’ the microbial content of the intestine and stimulate the production of an antibody called Immunoglobulin A (IgA), which is specific to certain microbes. This means that beneficial bacteria are not affected.

Additionally, it has been shown that the microbes in the intestine actually help the immune system to develop. For example, this can be seen in gnotobiotic mice, who have far fewer cells that are able to secrete IgA than regular mice.

Furthermore, a study by Ichinohe et al.

(2011) showed that exposure of mice to antibiotics during the development of the immune system impairs it during later life, possibly due to this exposure

causing decreased microbial diversity in the intestines.

Essentially, the more we research on the human microbiome, the more important it becomes in determining a large variety of health outcomes, and the more it will begin to affect standard health sector procedures, such as fecal transplants and antibiotic dispensing.

It has been shown to affect obesity, the development of the immune system and even mental health (though I didn’t have the space to go into it) through various mechanisms that we still hardly understand, and I predict that we will find that it affects much more, in time.

RESOURCES: https://www.coursera.org/course/microbiome http://en.wikipedia.org/wiki/Human_microbiome http://www.hmpdacc.org/ http://en.wikipedia.org/wiki/Microbiome#Immune_System http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3298082/

FURTHER READING: https://www.coursera.org/course/microbiome http://www.hmpdacc.org/

“VIBRIO CELLS 1” COURTESY OF ANTHONY D'ONOFRIO IS LICENCED UNDER CC BY 2.0

THE HUMAN MICROBIOME AND THE IMMUNE SYSTEM The adaptive immune system conducts humoural and cell-mediated responses against foreign pathogens. The humoural response is against pathogens outside of the body’s cells (hence ‘humoural’, as they existed in fluid around cells) and involves antibody production, whereas

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Why Do We Need Sleep ?

George Dyke gives an account on why it is essential that we get a good nightâ&#x20AC;&#x2122;s rest

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S

leep has been characterized as an altered state of consciousness, easier to wake from than a coma or hibernation, with relatively inhibited sensory activity, a declined ability to react to stimuli and inhibition of nearly all voluntary muscles. The main difference between wakefulness and that of being asleep is the lack of ability to react to stimuli.

WHY DO WE GO TO SLEEP? In all plants, animals, fungi and cyanobacteria there are circadian rhythms.

These rhythms are defined as any biological process that shows an oscillation of roughly 24 hours. The word circadian is derived from the Latin circa (around) and diem (day). The study of circadian rhythms is called chronobiology. These rhythms are built in to each human and also self-sustained. They can also be adjusted to the local environment (such as a different time zone) by zeitgebers.

Zeitgebers are external cues that cause a change to circadian rhythms, the most common and important zeitgeber being sunlight.

For example, the human sleep-wake cycle (a circadian rhythm) is controlled by the hormone melatonin (which chemically causes drowsiness and lowers the core body temperature). However when someone changes time zone their body must adjust and the circadian rhythm must change, this is caused by

FRANCIS CRICK (OF DOUBLE HELIX FAME) THEORISED THAT REM’S FUNCTION IS TO “REMOVE CERTAIN UNDESIRABLE MODES OF INTERACTION IN NETWORKS OF CELLS IN THE CEREBRAL CORTEX”. the melatonin secretion being inhibited by light (mainly inhibited by blue light of wavelength between 460nm and 480nm), which prevents drowsiness and the feeling of need to go to sleep. When it gets gloomy in the early evening secretion of melatonin starts (called dim-light melatonin onset) and drowsiness sets in. In this case sunlight has caused the change in the circadian rhythm and has acted as the zeitgeber. Studies have shown that power naps do not affect the circadian rhythms of a mammal.

However in recent times smartphones, televisions and other light-emitting gadgets have become a cause for diminished levels of sleep as people use them before they go to bed, or while in bed. These gadgets emit mainly blue light, which inhibits melatonin secretion, and this causes for people to unintentionally alter their circadian rhythm slightly. In adolescents their melatonin secretion schedule is delayed, causing for later sleeping and waking times. The sleep wake rhythm regulates the reticular

Table 1: Biochemical reactions in the body during different levels of wakefulness DURING WAKEFULNESS

DURING SLEEP

CORTISOL LEVEL IN THE BLOOD PLASMA

HIGH As it aids the metabolism of fat, protein and carbohydrates that are eaten while awake

LOW As an energy saving technique to keep energy stored in foods rather than metabolising them

MELATONIN SECRETION BY THE PINEAL GLAND

LOW While we are awake the body wants to stay awake

HIGH Melatonin is the hormone that makes us want to go to sleep

HIGH The body is very active, therefore a lot of respiration occurs

LOW There is very little movement at night, therefore a relatively less amount of respiration

CORE BODY TEMPERATURE

activating system, which is essential for maintaining consciousness. A complete reversal in the sleep-wake cycle can be an indicator of uremia, azotemia, and, potentially, acute renal failure.

There are 3 markers that can be used to measure the timing of the sleep-wake cycle in a mammal, as shown in Table 1.

WHAT ARE THE STAGES OF SLEEP? Normal sleep is mainly characterized as being made up of two parts: Rapid Eye Movement (REM) sleep and Non-Rapid Eye Movement (NREM) sleep. When we are asleep we go through the same pattern of sleep stages roughly 4 or 5 times a night. This pattern is usually N1 N2 N3 N4 REM. However as the night progresses the cycle alters slightly, with the mammal entering N3 and N4 sleep rarely (if at all).

REM sleep is seen as the most important stage of sleep, even though there has been no conclusive proof what its function is. REM is induced by the secretion of acetylcholine (a neurotransmitter that also lowers heart rate) and it is inhibited by serotonin secretion.

During REM, the brain arousal and oxygen consumption is higher than when the sleeper is awake, and is also the stage of sleep when dreaming occurs the most.

Moreover, descending muscle atonia (DMA) occurs. It has been hypothesised that this is due to the body paralysing itself to prevent self-harm during very vivid dreaming.

NREM is split into 3 stages (with N3 and N4 being merged to one as there is little to distinguish them). N1 is the period between sleep and wakefulness when muscles are still active and the eyes roll slowly (opening and closing occasionally). Also, during N1 the sleeper can have sudden twitches and they can

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experience very vivid hallucinations. N2 is not very different to N1 but the sleeper is harder to wake. N3 is also called Slow Wave Sleep (SWS) and during this phase many stimuli do not produce a reaction in the sleeper. This is the stage in which night terrors, nocturnal enuresis (bedwetting), sleepwalking and somniloquy (sleep talking) occur.

WHY DO WE NEED SLEEP? There are many theories regarding why we need sleep, and none yet have provided a definitive answer, however there are some that are more widely accepted than others.

There is a theory regarding sleep as a time when the brain consolidates certain types of memory. REM sleep has been showed to adversely affect the procedural and spatial memory of a human when not enough REM is attained. N3 has also been shown to be important in the retention of declarative memory.

Studies that have artificially enhanced NREM sleep duration have shown that the subjects have had improved recall of pairs of memorized questions. A study done by Tucker et al. (2006) showed that a daytime nap that solely contained NREM sleep enhanced declarative memory but had no effect on procedural memory. One study showed that a man who had sustained a shrapnel injury to the brainstem, which caused for him to be unable to enter REM sleep, demonstrated no memory impairment. Francis Crick (of double helix fame) theorised that REM’s function is to “remove certain undesirable modes of interaction in networks of cells in the cerebral cortex”.

This means that relevant memories are strengthened while “noise” memories are forgotten, a process called unlearning.

There is another plausible theory called the Ontogenetic Hypothesis of REM Sleep, which says that REM provides neural stimulation that allows for new-borns to form mature neural connections. This allows for a proper, healthy nervous system to develop.

This hypothesis has been backed up by the evidence shown by several studies regarding a lack of REM sleep and the adverse effects it has on maturing brains.

For example, a lack of REM in early life

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can result in behavioural problems, permanent sleep difficulties (such as insomnia or permanent nocturnal enuresis), decreased brain mass and a significantly higher-than-average rate of neural cell death. More support is shown for this theory due to the decreased requirement of REM required later in life. However one big consequence of this theory is that, effectively, REM has no effect on a mature brain and is therefore unnecessary.

Ionnanis Tsoukalas of Stockholm University published a theory in 2012 regarding the need for REM sleep that had a largely different basis to most others. He said that REM is an evolutionary transformation of the tonic immobility reflex (TIR) (otherwise called death feigning). He said that the basis for his theory was that the neurophysiology and phenomenology of REM and TIR are very similar (e.g descending muscle atomia occurs on both REM and TIR).

More proof for this theory is that both phenomena exhibit brainstem control, paralysis, sympathetic activation and thermoregulatory changes.

There are many more theories regarding the need for sleep, such as the hypothesis regarding monoamine receptor recovery published in 2002 by the University of California. They say that during REM these receptors shut down and recover to regain sensitivity to monoamines (e.g. adrenaline, dopamine, serotonin, melatonin and histamine) and their proof is that if REM is repeatedly interrupted, the sleeper will recover with longer REM duration the next time they go to sleep.

However there have been theories that have been widely accepted by the science community regarding why we need sleep. These include the expansion and contraction of the extracellular space increasing by 60% when the person is asleep, compared to them being awake.

This expansion and contraction effectively squeezes out harmful chemicals that build up in the brain to prevent damage to the cells. Another reason for sleep is that metabolism decreases by 10-15% when we are asleep, effectively saving energy. This is due to the decreased amount of cortisol present in the blood plasma.

Sleep deprivation has also been shown to hinder the healing of burn wounds in rats, opening up the hypothesis that sleep is needed for regeneration of cells.

Lastly, studies have shown a 20% drop in white blood cells (in rats) when they have been sleep deprived; therefore it can be deduced that a lack of sleep depresses the immune system, which increases the chance of infection.

WHAT HAPPENS IF WE DON’T SLEEP? A minor lack of sleep can result in yawning and a poorer level of performance doing complex tasks. However, the consequences of chronic lack of sleep are significantly more severe. The physiological effects include: muscle aches, memory lapses, depression, hand tremors, hallucinations, increased blood pressure (therefore increased risk of coronary heart disease), increased stress hormone levels and seizures. It also causes psychological conditions similar to the symptoms of ADHD and psychosis.

In 2005, a study was done (with 1400 participants) that showed people who consistently have 4 hours of sleep or less are more likely to get Type 2 diabetes due to an impaired glucose tolerance.

Also, a study in 1999 showed that sleep deprivation caused a reduced secretion of cortisol.

REFERENCES: http://www.dailymail.co.uk/health/article-90598/What-happensbody-youre-asleep.html http://europepmc.org/abstract/MED/9351134 http://www.maths.tcd.ie/~mnl/store/VertesEastman2000a.pdf http://www.ncbi.nlm.nih.gov/pubmed/12596522 http://web.mit.edu/dmalt/Public/9.10/newRun2.pdf http://en.wikipedia.org/wiki/Sleep http://en.wikipedia.org/wiki/Rapid_eye_movement_sleep http://en.wikipedia.org/wiki/Cortisol http://en.wikipedia.org/wiki/Melatonin http://en.wikipedia.org/wiki/Acetylcholine http://www.medscape.org/viewarticle/502825 http://www.nhs.uk/Livewell/tiredness-and-fatigue/Pages/ lack-of-sleep-health-risks.aspx http://integrativehealthconnection.com/wp-content/ uploads/2011/11/Sleep-loss-a-novel- risk-factor-for-insulin-resistance-and-Type-2-diabetes.pdf http://www.psychologytoday.com/blog/media-spotlight/201303/ exploring-the-mystery-rem-sleep Sleep: Why do we need it? Matt Davids, 2013, 1st edition