ISSUE
67
November/December 2014
€5 including VAT £4 NI and GB
SCIENCE
SPIN
IRELAND’S SCIENCE NATURE AND DISCOVERY MAGAZINE
www.sciencespin.com
SunSPotS
northern lights
WInnIng tHe raCe agaInSt drug reSIStanCe
Protein production
ask a scientist tuning into space SCIenCe WeeK
PHYSICS
In a spin
SCIENCE SPIN
Ireland’s science, nature and discovery magazine 6 issues a year covering science at home and abroad In newsagents throughout Ireland, and on subscription Subscribe on line from our website. €30 post included Ireland, UK and EU
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SPIN SPIN
Is there something in science that has you puzzled? Our panel of scientific experts is ready to answer your questions. Send in your question with your name and we’ll do our best to satisfy your curiosity. Email us at:
question@sciencespin.com Upfront
2
SCIENCE WEEK
8
S+T careers
10
Physics in a spin
12
A preview of some events from around the country
Making chips and keeping planes flying
Exploring the power of rotation
Tuning in to space
15
Basalt
18
Protein factories
23
Northern lights and sunspots
23
Ireland’s bid to join a European network of radio telescopes
Paddy Gaffikin describes the rock that covers a large part of Antrim
Understanding how tiny machines convert genetic code into proteins could help us win the race against drug resistance
Margaret Franklin explains why we sometimes see spectacular skies
Family science Christine Campbell on how to grow your own crystals
26
Weird and wonderful
28
Young Scientists
29
Dr How
31
Ask a scientist
32
Sive Finlay writes about how a parasite turns crabs into slaves
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Freshwater from the sea, downside of chlorination, and magnetic influence on life
Naomi Lavelle examines the science of snow
Our panel of scientific experts answer your questions
SCIENCE SPIN Issue 67 Page 1
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Recording life in the Antarctic
UPFRONT
FoR the past four years marine biologists have been compiling a list of species that inhabit the Southern ocean. As a result more than 9,000 species have been described. Dr louise Allcock from NuI galway, an expert in octopuses, was among the contributors, and she also took a strong interest in the phenomenon of bipolarity. Although it is unusual for species to occur on both poles, Dr louise said the way in which they diverged over time tells us a lot about evolution. As a species becomes more dispersed it can become bipolar, but because the flow of genes is restricted, the two populations begin to diverge.
Adélie Penguins, Pygoscelis adeliae. Photo: Alain De Broyer. The Antarctic octopus, Cirroctopus sp., with a leg span of almost one metre. Photo: C. d’Udekem d’Acoz, RBINS
Dr Louise Allcock, from NUI Galway was among those to compile information on more than 9,000 species.
Sea trout
For the past thirty years, scientists at the Eriff fishery at the head of Killary harbour have been assessing stocks of sea trout and salmon on an annual basis. Originally privately owned, the fishery, near leenane, was purchased by the State in 1982. In September a new research programme involving the release of sea trout fitted with acoustic tags was launched. According to Dr Ciaran Byrne, CEo of Inland Fisheries Ireland, the tags will help to determine the migration, distribution, habitat preferences and survival rates of sea trout and salmon smolts in the marine environment off the west coast. www.fisheriesireland.ie
Burning birds
Although arranging mirrors to focus sunlight on a boiler to produce steam might seem to be an environmentally harmless way to harness energy, the developers of a giant solar plant in the Mojave Desert have discovered that this is not the case. EIN News reports that the environmental group, Center for Biological Diversity, has raised an alarm about the number of birds being fried as they fly through the concentrated beams. the plant, which went into operation last February, has 300,000 mirrors reflecting light onto three giant towers that act as boilers producing steam to drive electricity generating turbines. the uS Fish and Wildlife Service now wants to know just how many birds are being killed before an even bigger solar plant, situated on a flight path between California’s biggest lake, the Salton Sea, and the Colarado River, gets the go ahead.
Marine Institute Foras na Mara
Our Ocean - A Shared Resource Ár n-Aigéan - Acmhainn Comhroinnte Ireland’s National Agency for Marine Research and Innovation An Ghníomhaireacht Náisiúnta um Thaighde Mara agus Nuálaíochta
www.marine.ie
SCIENCE SPIN Issue 67 Page 2
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UPFRONT
Food finders
VUlTURes are unusual in that they do not kill, but feed exclusively on carrion. however dead animals are not that easy to find, and as zoologists from TCD have found, two species of vulture in Kenya not only depend on keen-eyed eages to do the searching on their behalf but also rely on them to prepare the meal. In reporting on study of these birds, PhD researcher, Adam Kane, said that
Tawny and steppe eagles are better equipped to find carrion, and they use sharp beaks to open up the carcasses. Vultures, alerted by this activity swoop down and drive off the eagles, but not before the firstcomers have taken their fill of choice pieces. so, as Adam observed, the eagles do not lose out. Dr Andrew Jackson, Principal Investigator at TCD’s Centre of
Saving sight
When the eye’s cornea deteriorates to such an extent that sight is lost a transplant operation from healthy tissue from a donor can be performed. Unfortunately about 30 per cent of these procedures are not successful because the donor tissue is rejected. Throughout the world about 100,000 undergo this procedure every year, and although cornea transplantation is long established the high rate of rejection is still a big problem. however, this is about to change as researchers at nUI Galway report that rejection rates can be reduced dramatically by administration of mesenchymal stem cells. As Dr Thomas Ritter from the Regenerative Medicine Institute explained in the American Journal of Transplantation, these adult stem cells are readily available from bone marrow of donors and are easily grown. The development follows research showing that mesenchymal stem cells can modulate the immune response, dampening down inflammation and reducing the likelyhood of rejection. In a follow up study the Galway researchers are working with a number of collaborators around europe to study cornea transplant rejection in more detail.
Gut pain
Unless there is a very good reason to do so, antibiotics should not be given to babies. Antibiotics interfere with the natural growth of our beneficial gut microbes, and UCC scientists have now found evidence to show that negative effects are likely to persist into adult life. The scientists, from the Alimentary Pharmabiotic Centre and the Dept of Anatomy and neuroscience at UCC found that disturbing the gut microbiota in animals during early life increased their response to pain as adults. Although the gut microbiotica had returned to normal, this pain response was observed. According to Prof John Cryan this suggests visceral or abdominal pain which is common in adults, could be linked to an upset of gut microbiotica in early life.
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Biodiversity Research, said that these observations can help the vultures survive. Although once the most abandant birds of prey, vulture populations have declined, and they are under threat by habitat loss, poisoning and hunting. Vultures, he said, have an important role as recyclers of dead and decaying matter and they provide a valuable service by reducing the spread of disease.
Survivor
A sMAll insect, Polypedium vanderplanki, can survive almost total dehydration. The insect, a midge that occurs in northern nigeria, can lose 97 per cent of its body water, enabling it to survive extreme drought. As a team of scientists from Japan, Russia and the Us report, the midge can also survive extremes of temperature, from 90°C to minus 270°C, vacuums and high doses of radiation. In its home environment, the dry season lasts for six months or more, and droughts can persist for up to eight months. The larvae remain viable for 17 years or more. The scientists, who published their findings in Nature Communications, report that some of the genes that enable the midge to survive such harsh conditions are unique. normally, this high degree of dehydration would cause severe damage to the insect’s DnA, but as one of the researchers, Dr Takahiro Kikawada discovered, the species has the ability to repair this damage. In tests, normal physiological activity was restored in most of the larvae after rehydration.
Euclyptus under threat
There are hundreds of different Eucalyptus species in Australia, and about 13 of these have been introduced with success to Ireland. Some are being cultivated commercially for their decorative foliage, but in recent years a beetle pest from Tasmania has caught up with these exotics, possibly arriving as a passenger on imported plants. According to Teagasc, the beetle, Paropsisterna selmani, is a threat to these commercial planations because if leaves have been damaged by the beetle they cannot be sold. Treatment with insecticides is not an attractive option, so biological control, using a parastic wasp, Enoggera nassaui, is being investigated. Control using these wasps has been found successful in New Zealand, and Dorothy Hayden, from the Teagasc College of Amenity Horticulture at the National Botanic Gardens, is investigating this form of biological control in Ireland.
The parasitoid wasp enoggera nassaui in the act of parasitising a beetle egg.
Leaves of the decorative species e gunnii. Photo: Derek Ramsey The colourful leaf beetle pest Paropsistern selmani.
website: www.gsi Email: gsisales@gsi.ie
SCIENCE SPIN Issue 67 Page 4
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UPFRONT
Muscle origins
AnimAls have muscles, but when did these specialised bundles of cells first evolve? Scientists from the University of Cambridge working with colleagues from the Memorial University of Newfoundland have discovered some of the earliest examples in a relation of sea anemones that lived 560 million years ago. The fossils, which are thought to belong to the cnidarians, a group represented now by corals, sea anemones and jellyfish, have bundles of fibres, showing that they had acquired the ability to control body movements. Reporting on this discovery in Proceedings of the Royal Society, the scientists said that the fossils, found in Newfoundland and given the name Haootia quadriformis, are among the oldest in the world to show muscle development.
Marine projects
Left, fossils of Haootia quadriformis from Newfoundland and above, an artist’s impression of what they would have looked like in life.
Implanting neurons
PrimAry schools have been invited to participate in a marine related explorers education Programme. During the 2014 and 2015 school years workshops and other activities will be held at teacher education centres in counties Galway, Clare, Mayo and Sligo. More information and details about how to apply are available from www.explorers.ie or contact Noirin Burke at noirin@ nationalaquarium.ie
NeURoNS, produced by reprogramming skin cells, have been transplanted successfully to the brains of mice. Six months after the scientists from the Luxembourg Centre for Systems Biomedicine carried out this procedure, the neurons continue to perform normally. The researchers, led by Dr Jens Schwamborn and Katherine Hemmer commented that this raises hopes that treatment for diseases such as Parkinson’s may become possible in the future. It could be a long time before such treatments become a reality, but at least this success is a step in the right direction. Reprogramming skin cells from the patient, they explained, would have a big advantage in that the nerve cells are more likely to be accepted. With the mice, neurons implanted to the hyppocampus and cortex regions were not rejected, and they became fully integrated and functional.
Drug delivery
mAny of the newer types of drugs consist of proteins or genetic materials. A big problem with these drugs is that biomolecules become degraded before reaching their target. To overcome this, viruses that can naturally overcome barriers are used as carriers. Although these viruses are supposed to have been rendered harmless, they can give rise to unintended side effects. As researchers from Wageningen University working with colleagues from the University of Leiden, einthovan University of Technology and Radboud University Nijmegen have found, it is not the virus but its coat that matters most when it comes to packaging. For this reason the researchers focused on developing a trouble-free coat. This coat had to be as natural as possible, so after studying the structure of viral coat proteins, the researchers used yeast cells to produce an acceptable packaging. Reporting on this in Nature Nanotechnology, the researchers said that when mixed with DNA the protein spontaneously formed a protective coat around the molecules. The synthetic coating was found to be just as effective in delivering DNA to the target cells. The researchers commented that apart from being safer, the synthetic coatings are likely to become a useful tool in gene therapy and other applications that currently depend on viruses.
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UPFRONT
African giants
The dry deserts of North Africa were once tropical wetlands supporting a rich diversity of life. During the Cretaceous Period there were enormous dinosaurs, and one of the most spectacular of these was Spinosaurus, fossils of which were first discovered over a century ago by by a German palaeontologist, ernst Freiherr Stromer von Reichenback. During Allied bombing of Munich in 1944 these fossils were destroyed, but Stromer’s detailed notes survived. When some fossils, representing a partial skeleton of a Spinosaurus were found and smuggled out of Morocco, a young palaentologist, Ibram Nizar decided to investigate. As Science Spin reported in issue 33 (March 2009) Nizar succeeded in finding the site where the fossils had been found and since then a detailed reconstruction of the giant dinosaur has been created at the University of Chicago. An international team, drawing on Stromer’s notes, specimens from museums, CT scans and modelling of missing pieces, made a complete 3D life-sized replica model of the Spinosaurus. According to the scientists, this was the largest known dinosaur to have existed, and it was semiaquatic. Small nostrils high on the skull enabled Spinosaurus to breathe while swimming, sharp interlocking teeth were good for catching fishes, and short hind legs with muscular thighs shows that the dinosaur was adapted for paddling in water rather than walking on land. The fossils are on their way back to Morocco, where they are to form the centre-piece of a museum.
Mars as Gaeilge
LEARN about Mars and improve your Irish at the same time at a website developed by TCD’s School of Sciences in collaboration with the Department of Geography. Dr Mary Bourke from the Dept of Geography said that the website is an excellent way to promote language learning while stimulating interest in Marsian science. http://beautifulmars-irish.tumble.com and http://uahirise.org/ga
Space junk
The rising number of cost-cutting mini-satellites is increasing the risk of collisions between orbiting objects. Dr Hugh Lewis, from the University of Southampton said that between 2003 and 2013 about 160 of these small satellites have been launched. Known as CubeSats, each is about 10 cubic cm in size. CubeSats provide an opportunity for data and communication companies to get into space, but because they cannot be manoeuvered there is no way to avoid a collision and they cannot be desposed of at the end of their working life. According to Dr Lewis CubeSats have been involved in more than 360,000 close approaches of less than 5km since 2005. Based on projections, the number of close approaches will increase, possibly to millions over the coming 30 years, and some of these will result in collisions.
Lichen expert
The Chinese Mitten Crab. Photo: M Milne-Edwards
Mitten crabs
The Chinese Mitten Crab, a native of east Asia, has been spreading across north east Europe. Recorded in the Thames in 1935, the crab has now reached Scotland. According to scientists from the University of London and the Natural History Museum, the crab poses a threat to salmon, trout and other native species. Dr David Morritt from the University of London said that the crabs could have a devastating impact on fishing rivers. It is thought that the crabs could have arrived with ballast water in shipping. Spending most of their life in fresh water, the crabs return to tidal estuaries to mate, and after spending the winter at sea, the females return to lay their eggs. On hatching, the larvae head upstream to fresh water. While posing a serious threat to fisheries, the crab is a delicacy in China. Although present now in England, Wales and Scotland, only one sighting has been recorded so far in Ireland. The crab, Eriocheir sinensis, has furry mats on its claws, giving rise to the common name, Mitten Crab.
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The latest plaque to be erected to commerate Irish scientists recalls Matilda Knowles. Matilda, born 1864 in Ballymena, was an expert in lichens and was the first botanist to note that they grow in distinct zones along the seashore. The plaque was unveiled at the National Botanic Gardens, Glasnevin, where Matilda, as a non-pensionable assistant was in charge of the herbarium. Among her contacts was Roger Casement, and the rubber plants he donated are preserved in the collection. Maltilda Knowles who died in 1933 published a catalogue of 800 species, about 100 of which had not been recorded in Ireland before. The memorial was erected by the National Committee for Science and engineering Commemorative Plaques
Looking down on the Albertine Rift, one of Africa’s most biologically diverse areas. Although rich in wildlife, the area, is torn apart by conflict adding to the problem that not enough food being produced to support a dense population. in this composite of three Envisat radar images, we see a range of volcanoes surrounded by cultivated plots and national parks where efforts are being made to protect wildlife. Among the species under threat from poaching are the mountain gorillas. Two of the volcanoes, nyamurangira and nyiragongo are among the most active in Africa, the former, to the east, with an elongated lava flow (in red), erupting every few years. The Congo-Rwanda border runs between two of the volcanoes to the lower left and a cluster of white spots along Lake kivu (blue) is goma city. Although mountain gorillas are under threat from poachers, their population, currently recorded as 880, is reported to be increasing slowly. Photograph by Dave Proffer.
The power of science ons.
Ireland’s 19th annual
SCIEnCE WEEk From Lego robotics, magic science shows, ‘Coding for Adults’, a ‘Molecular and Synthetic Biology’ workshop, virtual reality displays, a crystallography workshop, science busking, robot soccer displays, opportunities to meet with astronaut Greg Johnson, and a nationwide tour, including school screenings, of Unbreakable: The Mark Pollock Story, Science Week 2014 offers a unique opportunity to explore the power of science and get answers to burning science questions.
Some highlights l The Curiosity Lab, Smock Alley, Temple Bar, Dublin, 8th and 9th November, will transform Temple Bar into a curiosity filled hub with free adventures in science, play and curious technology for all the family. l Earth Festival: Science through Art, Letterkenny Town Park, Co Donegal: 11th -13th November. A series of illuminated sculptures inspired by cutting edge scientific research accompanied by a programme of workshops, seminars and tours. l ReelLIFE Science; video competition for school students. Winners will be announced during Science Week. l Cell EXPLORERS course for teachers, Galway Education Centre, 15th November: ‘Working scientifically in the primary school classroom’.
l Junior Einstein shows in schools across the Midlands, 11th – 14th November. l What’s a Wakatobi? Abbeyleix Heritage House, Ballyroan Rd, Abbeyleix, Co. Laois, 10th November. An opportunity to hear first-hand about the discovery of a new species by Irish researcher Trinity zoologist Seán Kelly. l The Poetry of Physics, the Physics of Poetry, Luan Gallery, Athlone, 11th November. Conversation with Poet and Physicist Iggy McGovern. l A nationwide tour, including school screenings, of Unbreakable: The Mark Pollock Story to demonstrate how science can have a positive impact on people’s lives, as reflected in Mark’s rehabilitation following blindness and an accident which left him paralyzed.
Galway Science and Technology Festival
10th – 23rd November 2014 The Galway Science and Technology Festival will run from 10th – 23rd November as part of national Science Week with lots of fun interactive science activities for students, parents and teachers to get involved in. Cell Explorers will be running events such as the ‘Fantastic DNA Roadshow’ available to visit primary and post-primary schools, which will allow budding explorers discover DNA by building a DNA double helix and extracting DNA from bananas to take home, as well as the Cell Explorers CPD course for teachers, which will give them experience of hands-on activities aimed at exploring ’the scientific method and living things’. Visit www.cellexplorers.com and http://www.galwayscience.ie for more information.
For full up to date programme visit www.science.ie SCIENCE SPIN Issue 67 Page 8
9th to 16th november 2014 A key objective of Science Week is to inspire young people to take up studies and careers in the disciplines of science, technology, engineering and mathematics (STEM). It also seeks to demonstrate, to people of all ages, the importance and relevance of science to the future development of our society and economy.
www.science.ie Midlands Science Festival
An action-packed programme has been put together for this year’s Midlands Science Festival which will run 9th – 16th November. There will be an exciting range of new events and a return of some of the most popular sessions from last year, with the overall aim of inspiring, educating and entertaining through science. There are plenty of events planned for mini-scientists this year such the Junior Einsteins Science Club and a return of the Reptile Zoo Village, where pupils will have the opportunity to pet a snake or a large spider! In addition to fun and innovative demonstrations and talks, there will be a focus on activities that will help encourage young people around the Midlands region to develop an interest in STEM subjects beyond the confines of the curriculum and increase their awareness of potential careers in those areas. Some inspiring events will be on offer for the general public too. This will include the return of last year’s ‘Science Movie’ night, which is a unique audiovisual experience featuring some of the best science stories from the world of animation, radio and television. With top scientists such as Professor Luke O’ Neill attending, a number of alchemist cafés full of lively debate and discussion during the week are also promised. Check out the website to see updates to the full programme of events: http://www.midlandssciencefestival.com Stay up-to-date with the festival through their Twitter channel: https://twitter.com/ curiouskim1 www.midlandssciencefestival.com
8000 events 250,000 participants
Some midlands events Monday 10th November ask for evidence Challenging misleading claims in science and medicine. 1 to 2pm at Athlone IT
Tuesday 11th November antibiotic resistance Dr Fiona Walsh from NUIM talks about the rise of multidrug-resistant bacteria. 11am at Athlone IT alchemist Café Prof Luke O’Neill and Sile Lane discuss hot topics in science. 8pm at Athlone IT
Celebrate SCienCe is a festival of science that will coincide and run in conjunction with Science Week Ireland. Lots of fun and educational events of interest to school children and parents. In Cork, Celebrate Science will kick-off with a Family Open Day on November 9th in the UCC Western Gateway building with over 30 different workshops and displays for adults and children. Throughout Science Week there will be a series of lectures taking place in different departments in UCC, primary school visits, secondary school science workshops, and tours of UCC lab facilities. In Limerick, the main event for Celebrate Science will take place on Saturday 15th November at the Milk Market & Hunt Museum in Limerick city centre. In Dublin, there will be a science-based film festival with a series of workshops and discussion panels running from November 13th to 15th.
SliGO
Wednesday 12th November Silence of tenrecs Sive Finlay, author of Science Spin’s Weird and Wonderful series talks about the small mammals of Madagascar. 12 noon at Mountmellick Public Library, Co Laois. And at 4pm at Athlone IT alchemist Café Gary Donohoe, Head of Psychology at NUIG, talks about the science of the mind. 8pm at Hugh Lynche’s Bar, Tullamore, Co Offaly. the inventive irish Mary Mulvihill talks about how Irish scientists helped to create the modern world. 8.45pm at Portlaoise Library, Co Laois. Thursday 13th November enjoy the coffee Craig Slattery from UCD talks about the science of coffee. 10 to 11.30 at The Coffee Club, Tullamore, Co Offaly. Communicating science Dr Craig Slattery from UCD talks about engaging public interest. 2 to 5pm at Athlone IT Saturday 15th November Makerspace workshops Learning how to make smart things. 2 to 6pm at Making Space, Custume Place, Athlone.
9th to 16th Programme for the week includes the Science Fair on Sunday 9th November. At 7.30pm each evening there will be a lecture open to the public. www.sligo.ie
Discovery Festival, Cork
November 10th to 22nd In this exciting fortnight of Discovery, Lifetime Lab, CIT/Blackrock Castle, Rob Hill and Paul McCrory hit the road once more to bring workshops and shows to 2,500 students in classrooms and communities across Cork city and county. Another 2,500+ will visit the central exhibition in City Hall with their school, and 4,000 will come see the City Hall show with their family. Special events this year include some very serious games and the Cork link to sensors that are used on the International Space Station. Check the website www. discoverysciencefestival.ie from Oct 1 for full details and booking.
GalWaY SCienCe 10th to 23rd November Physics with Declan Holmes, Xtraordinary science with Sue McGrath and workshops for primary school pupils with Dr Naomi Lavelle, Dr How, on the science of sound. www.galwayscience.ie SCIENCE SPIN Issue 67 Page 9
4th November Scientific Sue presents three science magic shows to primary and secondary school students. 9am to 3.30pm at John Bosco Centre, Donegal Town. christopherhegarty@donegalvec.ie 9th November touring tyndall An opportunity to look inside the state-ofthe-art labs in the Tyndall Institute. 7 to 9am, Lee Maltings, Cork. info@celebratescience.eu 10th November Coderdojo, workshop for junior and senior students. 6 to 8pm at Valentia Island Resource Centre, Co Kerry darearca.ie@coderdojo.com 11th November Science experiments workshop with Dr trish Murphy for primary schools. 10.30am to 12.30pm Carndonagh Library, Co Donegal. ucutliffe@donegalcoco.ie Thursday 13th November regional finals in the irish Science teachers’ association schools quiz. 7.30pm at 12 different locations. Details at www.ista.ie 15th November Growing crystals: workshop on how to make your own. 12 noon to 3pm Hunt Museum, Limerick. Science Café Series of short talks on everyday science. 6 to 7pm at Hunt Museum, Limerick. 16th November Open day on science and technology GMIT Castlebar, Co Mayo 23rd November Cell explorers workshop A hands-on workshop on cellular and molecular biology for parents and children 11am to 3.30pm at NUI Galway galwaysciencefestival.gmail.com exploring the brain Workshop on the basics of brain biology with interactive and hands-on activities. 11am to 5pm at NUI Galway galwaysciencefestival.gmail.com
For full up to date programme visit www.science.ie
Careers of the future Judith Moffett from CPL runs workshops on science careers. 2pm at Athlone IT
Celebrate science festival
CAREER PROFILE
Supported by
Maria Delaney talked to Michael Keogh about his work as a Ryanair aircraft engineer. Describe your typical day? I am a B2 avionics maintenance engineer so I work on electrical, instruments and radio systems. B1 engineers work on airframe and engine systems. We work 12-hour days, working two days then two nights, followed by four days off. On a typical day, I carry out a technical status review of our operating aircraft, plan for scheduled maintenance and provide technical support for our operating aircraft in Dublin and abroad. On nights, we carry out routine and scheduled maintenance. What’s cool about your job? Every day is different; there are always new challenges. I get great job satisfaction when I have to recover an aircraft with a technical issue that prevents it from flying, especially when abroad. To recover an aircraft, we have to find the cause, repair or remove and install a component, followed by a complete test of the affected system. What are the main challenges? Working in a high-pressure environment and maintaining our aircraft in a safe, efficient and cost-effective manner. I must keep up to date with my Irish Aviation Authority (IAA) licence, company approval and recurrent training. Another challenge is learning about new aircraft and systems in a constantly changing industry. How do you get an IAA licence? After completing an apprenticeship and on-the-job training, you can apply to do IAA exams. Once completed, the IAA issues a licence.
What advice would you give to someone considering this job? Engineering and science subjects are extremely important as they help you to understand aircraft systems such as aerodynamics, pneumatic, hydraulics, jet propulsion, radio theory, electrical theory and instrumentation. What subjects did you take in school? I took maths, English, Irish, engineering, technical drawing, physics and French. The science and engineering subjects were essential during my apprenticeship and I use them every day in work. What did you do after school? I did an apprenticeship in aeronautical engineering with Ryanair in conjunction with FĂ S in Shannon and Dublin Institute of Technology (DIT). During my apprenticeship I did night classes in radio, instruments and electrical theory. What inspired your interest in engineering? Having a curious mind; I always loved the practical side of technical drawing, metalwork and physics.
SCIENCE SPIN Issue 67 Page 10
Maria Delaney talked to Morven Duffy about making computer chips. Morven has been working at Intel for the past 15 years. What is a process engineer and what do you do? Intel has a few hundred process engineers in Leixlip. Each one has responsibility for a number of process steps. We start with a silicon wafer and build a load of integrated circuits into it. My area is called metals. I work with complicated machines and ensure they operate consistently and at a reasonable cost. What are the wafers for and what size are they? We build hundreds of chips on to a silicon wafer that is 30cm across. We’re starting a new process using Intel’s newest technology called Broadwell.
Morven Duffy, right, Process Engineer at Intel Ireland
We use a measurement called the gate length, which is the basic measure of how small a chip can be manufactured. The new gate length is 14 nanometers (nm) – a human hair is around 75,000nm in diameter – and the most advanced in the world.
What subjects did you take in school?
What are the main challenges?
What did you do after school?
Some of the layers we use to build chips are so thin that the material doesn’t behave as expected so that is difficult. Keeping the yields up (how many good chips we get off a wafer) is very complicated as there’s a lot of reasons why it might not work.
I did applied physics in Dublin City University in 1995. I had to do a six-month work placement, which I did in Intel. Intel hired a bunch of us when we finished college.
Another challenge is the travel. Intel releases a new product every two to three years. They are developed in Oregon in the US and transferred to Ireland. When we are doing a process transfer, we have to live abroad. In the last three years, I’ve spent nine months in Oregon and just over a year in Israel. What’s cool about your job?
I picked physics, chemistry, biology, applied maths and German. When I was choosing my college course, I decided to go with the subject I liked best – physics.
What kind of work experience would provide a good background for this position? Anyone interested in this role should get experience in a manufacturing-type job. What inspires your love of engineering? My family has always been quite technical. We were very familiar with computers and had a laptop at home in 1990. That background has definitely fed through.
I get to play with really expensive machines!
Cpl Science, Engineering & Supply Chain is unique in that we have strategic partnerships with the majority of the pharmaceutical, biotechnology and medical device companies in Ireland and globally. As a result of our reputation for quality, excellence, delivery and understanding of our clients’ needs we are also the first port of call for any new scientific business ventures that are considering setting up in Ireland.
Cpl truly appreciates and values finding the “perfect technical match” and we provide candidates and clients with an individualised, quality service, carefully tailored to meet the specific needs of our customers.
CPL Resources plc, 83 Merrion Square, Dublin 2, Ireland. Phone: +353 1 614 6000 Email:info@cpl.ie www.cpl.ie
SCIENCE SPIN Issue 67 Page 11
ThE PoWEr of SPIN A roller coaster at the Olympus Theme Park, Wisconsin, designed and built of timber by the Gravity Group engineers.
Simply observing what happens when balls bounce back or watching how rotating wheels seem to defy gravity can show us how much we depend on spin. Tom Kennedy reports on how the physicist hugh hunt tells us not to throw away our old toys.
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hat is the connection between turning a telescope in space, using a light weight to lift a heaver one, and staying upright on a bicycle? As Hugh Hunt, from the Department of Engineering at the University of Cambridge explained at the recent Institute of Physics conference in Dublin, the answer is in how things spin. For some reason, he said, centripedal force is not being given the attention it deserves, and also it is not being explained properly in schools. Yet, as he argues, young children are quite capable of observing how spin works. By simply observing spinning objects, he said, we begin to grasp what’s happening without having to work it all out from abstract theory. This is something that can be done with everyday objects, and as Hugh remarked, physics provides us with a great excuse for not putting away your old toys.
We can, for example, talk about how spinning particles should behave, he said, but this is unlikely to mean anything to most people until they observe what happens with actual particles. The small bouncing balls that children like to play with provide a good example of a particle behaves, and Hugh used one of these to demonstrate how spin comes into play. When the ball is bounced between two surfaces, such as a solid floor and the bottom of a table, we expect to see it come out the far side, but what actually happens is that the ball returns along almost exactly the same path. We can try to explain this using fairly simple equations, said Hugh, but just seeing what happens makes it a lot easier to understand why the ball returns. When an aircraft lands, said Hugh, we just know that the wheels, on touching the runway, will turn. That does not
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surprise us, so why should we expect the bounding ball to behave any differently? In fact, the ball does exactly the same. On hitting a surface it begins to twirl, but what causes confusion is that we don’t take into account that the direction of spin reverses with the next impact. When the ball hits the floor it begins to spin, but then when it hits the bottom of the table the spin is reversed, sending the ball back down to the ground to bounce back again. With this simple demonstration, we see how the angular momentum of spin is conserved, and as Hugh said, this is something that primary school children can easily understand. Spin, he said, is thought to be complicated, yet it is something we encounter in everyday life. We can cycle because of spin, and another familiar example is the spinning top. As every child knows, the top will keep spinning as long at it turns fast
To conserve energy the spin of a bouncy ball goes into reverse making it return
enough. Spin creates a force that keeps the top up, and even if turned on its side and suspended on a string, the top seems to defy gravity just like a gyroscope. When suspended on a string, the spinning object does not seem to have weight at all, and at first this seems to contradict Newton’s Second Law. Surely the string should carry the weight? Obviously this does not happen, because, in fact, the top is not defying gravity at all, its force is being coupled, or combined, to that of spin. When spinning slows down, gravity wins, and the top will fall. While explaining why these forces occur is difficult, Hugh pointed out that we get a very good idea of how spin works by observing it in action. Another good demonstration of how spin works is in how an object, such as a tennis ball, can by twirled around to lift a heavy weight. If a tennis ball, attached to a long string threaded through a tube is swung around in a circle, the end of the string becomes a crane capable of lifting a heavy weight.
In describing what’s going on, Hugh said he likes to avoid words like momentum, torc and vectors. “It’s a bit like the word calculus, it just turns people off,” he said, adding that it would be much better just to talk about couples and arrows. Everyone immediately understands what an arrow means, and in primary school children have the added enjoyment of making them and moving them around. Arrows, said Hugh, provide a clear impression of force, and one of the advantages is that, unlike vectors, they are easy to select and manipulate. The word couple, he said, immediately conveys the idea that those arrow-like forces act on each other to produce a combined effect. As a distinguished physicist, Hugh obviously has nothing against complex mathematics, but he said getting the concepts right to begin with makes an enormous difference in how we learn about spin.
Hugh Hunt shows how everyday objects can be used to demonstrate the power of spin SCIENCE SPIN Issue 67 Page 13
By rotating around in a circle a lightweight object can lift a much heavier weight
A rotating wheel can he held up as if it has no weight
Space telescopes and ice skating
normAlly, if we wave our arms about we would not become aware of spin. However, if standing on a freely-rotating surface we would find that a wave to the right makes us twirl to the left and, vice versa. Starting with arms out in a swing and bringing them in to the body changes the angular momentum, making us twirl faster and this is now those magnificent ice skaters instinctively make use of the fact that the energy of spin has to be conserved. instead of waving our arms, holding a wheel rotating to the right will also make us go left, and if the wheel is inverted, we go to the right. in much the same way, spin is being used to turn telescopes in space. There is no friction or gravity, so when a wheel is turned clockwise, the telescope responds by going anticlockwise, and because this is something that can be controlled with great precision, spin is used extensively in space.
Tossers
Spin comes into play in unexpected ways, such as when something solid like a book is tossed up into the air. When a book, held lengthways and face up, is tossed up into the air, it twirls and always comes back with the front down. Toss it higher, and the same happens. As long as the axis is lengthways the result is always going to be the same. What might might seem suspiciously like magic is actually due to a complex coupling of spin, gravity and kinetic forces.
Cats are masters of spin, always landing on their feet. For many years scientists wondered how cats manage to do this without violating the strict rule that angular momentum has to be preserved. However cats are very flexible and during free-fall they instinctively change shape so they manage to make a controlled flip-over to land upright on their paws. Right, during free-fall a flexible back enables a cat to change its shape.
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Reaching out to make European connections Ireland scientists have an opportunity to become partners in boosting the performance of a European network of space telescopes. As Tom and T A Kennedy report Birr in Co Offaly is the ideal location for an Irish station.
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hile optical telescopes show us the visible Universe by gathering light, radio telescopes work by detecting the longer waves that are invisible to us. Our eyes can only detect a small portion of the electromagnetic spectrum, and as Peter Gallagher, Associate Professor of Physics at TCD explains, being able to detect longer waves enable us to continue observing beyond light. While many astronomers use radio telescopes to look back in time by probing the depths of space, the longer waves are of interest to Peter Gallagher and his group of researchers because of what they can reveal about solar storms. Like most scientists, Peter can only conduct research if he has access to the right kind of facilities and this is why he is so keen to see Birr in Co Offaly become part of the LOFAR network of radio telescopes. Gaining adequate access to internationally-shared facilities, he said, is a serious problem for many scientists working in Ireland, and with LOFAR we have an opportunity to do something positive to improve that situation. The Low Frequency Array, LOFAR, explained Peter, originated with a proposal by the Director of Leiden University in Holland, and UCD physics graduate George Miley, to boost radio telescope performance by combining data from a number of stations. Miley was interested in probing more deeply into the early Universe and he also wanted to improve Europe’s capacity in this field. In 2006 construction began in the Netherlands, and soon afterwards four
Top, the LOFAR core, situated in the Netherlands. Above, the LOFAR network with the possible connection to Birr in Co Offaly. Right, for many years the telescope at Birr was the largest in the world. The LOFAR radio telescope on an adjoining site would continue a great astronomical tradition among relatively radioquiet surroundings. Geographical location would also improve overall resolution and enhance the standing of Irish scientists
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given the go-ahead said Peter gallagher, Ireland’s radio telescope could be up and running by 2015
other European sites were set up, leading Miles to comment happily that the project had grown into something much more ambitious than his original proposal. There are now LOFAR stations in Germany, Sweden, the UK, France and the Netherlands, streaming data to the University of Groningen for processing. Further expansion of LOFAR, represents an exciting opportunity for Ireland, said Peter Gallagher, and for this reason a consortium representing a range of organisations is making a bid to establish a radio telescope in Birr, Co Offaly. Apart from TCD, NUI Galway, DIAS, Armagh Observatory, Queen’s, UCC, NUIM, UCD, DIT, CIT, UL Grid Ireland and the Irish Centre of High End Computing are involved in this group. As Peter observed, the range of participants indicates just how important LOFAR is to the science community in Ireland. Basing the telescope in Birr makes a lot of sense, both for historic and practical reasons. For 70 years the Leviathan six
foot telescope was the largest in the world, and its creator, the Third Earl of Rosse, was the first to observe a spiral galaxy. Added to this historical continuity are two other significant advantages; lack of electromagnetic interference and distance from all the other stations. For lack of radio interference Birr is ideal. Near cities, radio signals are swamped by Wi-Fi, mobile phones and radio, but the midlands, said Peter, is one of the quietest places in Europe. Distance from the other stations also means that the overall resolving power of the network would increase. In a paper making a case for Irish participation, the LOFAR consortium pointed out that “these low frequencies represent one of the last unexplored regions of the radio spectrum and consequently offer vast scientific return. The detection sensitivity of LOFAR will be hundreds to thousands of times better than previous prototype low-frequency telescopes.”
As Peter explained, extending the LOFAR network would make Europe a world leader in radio astronomy, and Ireland would benefit by participating as an equal partner. LOFAR would provide a great training base for people to go into astrophysics, it would attract people from abroad, and as Peter commented, we should not forget the potential for spin-offs. For example, the Wi-Fi that we all use to communicate on the go came from radio astronomy. When John O’Sullivan, who had begun his career with The Netherlands Foundation for Radio Astronomy, co-authored a paper on networking standards that supported aggregation of data from multiple antennas, he became the founding father of Wi-Fi. Support for the project is strong. Financial high-fliers such as Dennis O’Brien, Dermot Desmond and software entrepreneur John Hogan like the idea and have made quite sizable contributions and Birr school pupils have collected €700. The target, said Peter is €1.5 million, so fingers are crossed that the State will step in to close the gap. Four new LOFAR stations are due to come on stream over the coming months, three in Poland and one in Germany. Adding another would bring down the cost per station, said Peter, so now is the time to establish a footprint in Ireland. If we miss out now, he added, there might never be another opportunity to become directly involved in LOFAR. Given the go-ahead, the Irish station could be up and running by 2015. The site is ready, and the equipment can be shipped in and assembled fairly quickly. “Its like the flat-pack of radio astronomy,” said Peter.
WorkINg IN ISolatIoN ISOLATION is far from splendid for scientists who are cut off from shared resources, and as Peter Gallagher commented, exclusion from international organisations such as CERN, the European Organization for Nuclear Research, or of the European Southern Observatory is like clipping the wings of our high-flying scientists. Limiting access to international facilities, he argues, is not a smart way to retain the best scientific talent. With the European Space Agency, membership has paid off, particularly for the high-tech end of industry. By staying out of CERN and ESO Ireland runs the risk of trailing behind
international science and, as an outsider, industry is not going to pick up spin-out opportunities and contracts. CERN has a high profile, but as Peter said, not that many people would know about the European Southern Observatory. Yet the facilities, perched high up in the mountains of Chile, is of great interest to a sizeable scientific community in Ireland. The ESO, established in 1962 has some of the largest and most technically-advanced telescopes in the world. It is a shared resource, supported by fifteen countries. Ireland, like Luxembourg, stands out because it is not a member. Among scientists, said Peter, there is a sense of
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frustration at being excluded from such an important organisation. “For a country that goes on about the smart economy, not to be a member of ESO is crazy,” he said. To many people astronomy might seem fairly abstract, but it acts as a powerful driver for technology. Companies such as IBM are using knowledge gained from astronomy to solve big-data processing problems in medicine, he said, and if astronomers had not wanted to push out the boundaries of imaging we would not now have the ability to capture images on our mobiles.
Irish scientists are at risk of becoming isolated because Ireland is not a member of CERN or ESO. On the other hand, membership of ESA has brought many benefits to Ireland, particularly for industry. The European Southern Observatory is a shared resource supported by fifteen countries. Scientists from member countries work on some of the world’s most advanced facilities. The La Silla site at 2,400 metres above sea level in Chile is home to ESO’s original site. At La Silla, among others, there is a 3.6 metre telescope, the New Technology Telescope with a flexible computer-controlled mirror and the 2.2 metre Max-Planck telescope with a 67 million pixel wide imager.
Watching the Sun One of the reasons why Peter Gallagher’s group keeps a close eye on the Sun is to predict when stormy space weather is on the way. Gigantic flare-ups can shower the Earth with charged particles and create magnetic disturbances that can knock out our satellite communications. As Peter explained, we have become very dependent on GPS to find our way around, but following a solar storm, there can be loss of signal or a shift in location. For an emergency service this could mean arriving at the wrong address, and for the military it could mean bombing the wrong target, and this is not the only way that solar storms can affect us. “We have all these wires running around the country,” said Peter, “and they are like giant antennas.” The electromagnetic disturbances caused by flares generate a current, and the surge can burn out transformers.
This is not an everyday occurrence, and for some unknown reason sunspots flare up every eleven years, so every so often we go through a period of higher risk. In 1989 Canada was hit following a big solar flare causing a massive power failure. In the depths of winter, five million people were left without power for nine hours. To minimise the chances of this happening here, Peter’s group works with eirgrid, modelling the system to identify any vulnerabilities so that they can be engineered out. Improving prediction, said Peter, would help, and this is something the group is working on. Sunspots are huge, bigger than the earth, and as Peter said, if we want to get good forecasting “we need to know what’s going on.” However, this is not easy, and Peter said it’s a bit like looking at swirls in a river and trying to predict when one is going to break off.
While understanding what’s going on is a challenge, the group and scientists all around the world can see what’s happening in high definition and almost in real time. This is the feed from the Solar Dynamics Observatory, launched in 2010 to provide continuous observations of the Sun. The spacecraft has a direct, dedicated, high-speed link to a ground station in new Mexico. When the spectacular images arrive across the world they are just two hours old, said Peter. Peter’s group is currently working on the software for a new Solar Orbiter mission due for launch in 2017. With eSA preparing the craft and nASA paying for the launch, the craft will fly by Venus, then past Mercury and on to circle the Sun. “This will be the closest fly-by yet,” said Peter so the craft will need special protection against heat. That sunblock shield, he said, is being supplied by an Irish company, embio, based at UCD under a contract with eSA worth half a million euro. There will be twelve instruments on board, some for images, others for data, and as Peter explained his group’s job is to clean up and make sense of all this information. Peter said he is very excited about this mission that will send back extremely high definition close-up images of the Sun’s surface. As he remarked, for fifteen years he has been looking at images of the Sun and they never cease to amaze him. A massive event in 2012 with a filiament travelling out from the Sun’s surface at over 100 km per second. Image: Solar Dynamics Observatory, NASA.
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ASPECTS OF IRISH GEOLOGY EXPLAINED — SIMPLY
Paddy Gaffikin on what we need to know about
IrIsh basalt
...there is no definitive answer to all geological questions. Our knowledge increases and our interpretations change through time, but fundamentally we always need exposures of rocks, such as on the coast and in quarries, to piece together the jigsaw of Earth’s history. Dr. M. Parkes, Geologist, National Museum of Ireland. (2012).
Early morning at the Giant’s Causeway. About 37,000 columns occur beside sea level. Photo: NI Tourist Board. Around 60 million years ago, Ireland was approaching the latitude of presentday France and widening of the North Atlantic was proceeding – that is the European tectonic plate, which includes Ireland, was pulling away from the American plate. This ‘pulling’ caused the crustal rocks of the north-east of Ireland to stretch, thin and weaken, thus allowing deep fractures to develop. The basaltic magma ascended from deep in the Earth, through the fissures, to spill out over the surface of the land.
The Giant’s Causeway
Mthe north-east of the country, and
ost of the basalt in Ireland occurs in
most of this is in Co. Antrim.
What is basalt?
Basalt is an extrusive (or volcanic) basic igneous rock. It is called ‘extrusive’ because it is formed from very hot (over 1,000°C) molten magma, rising from deep in, or below, the Earth’s crust and then extruded onto the surface when it is called lava. The term ‘basic’ refers to it having a relatively high concentration of the oxides of iron, magnesium and calcium, because these oxides are ‘bases’ (a chemical term). In appearance, fresh (unweathered) basalt is a dark grey to black, finely crystalline rock. The main mineral present in Antrim Basalt is augite and, because it contains quite a high proportion of iron, it helps to give the rock an overall dark appearance and make it comparatively heavy. (Basalt has a higher density than, for example, granite.) Basalt exposed to weathering by air and water commonly has a rusty-brown surface. The weathered patina, like the rust on iron, is composed of iron compounds. Basalt is finely crystalline because the lava cooled so quickly, on contact with the air, that the crystals had little time to grow to any size. It is generally so fine that the individual minerals cannot be seen clearly with the naked eye, or even with a hand-
lens. So how can we see them? This requires a laboratory procedure which entails cutting a thin slice of the rock, mounting it on a glass slide, with suitable adhesive, and then grinding it down to a thickness of 30 microns (so light can shine through it) and then studying the thin section under a polarising microscope.
When and how did Antrim Basalt form?
Antrim Basalt contains radioactive chemical elements (e.g. radioactive potassium which, over a fixed period of time, decays to the more stable argon) that enable the rock to be dated. Radiometric dating shows the rock is around 60 million years old. That is, the basalt in north-east Ireland formed a few million years after the dinosaurs became extinct. Conditions in Co. Antrim at this time would have resembled those in central Iceland today. A sample of unweathered basalt from Co. Antrim. Note however, that much of the basalt occurring in the county is weathered.
2cm
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The best-known exposure of basalt in Ireland is at the Giant’s Causeway, near Portrush, on the north coast of Co. Antrim. In fact, it is Ireland’s most famous geological site. Due to its importance in the development of geology as a science, it has been designated a World Heritage Site, so no sampling or hammering is permitted here. The area is characterised by dramatic columnar basalts – about 37,000 columns in total at sea-level – most of which are hexagonal in shape but there is also a high percentage (one count suggested 30 per cent) of pentagonal ones and four-, seven- and eight-sided columns are known. There are also imperfect instances of nine- and tensided columns. Legend has it that an Irish giant, Finn Mac Cool, constructed the basalt rocks, in the form of a path, enabling him to travel dry-shod across the sea to confront his Scottish rival Benandonner. Certainly similar, but not just as spectacular, columns occur on the island of Staffa, in Fingal’s cave. But geologists tell a different story! Around 60 million years ago, molten lava cooled after becoming trapped, or ponded, in a river valley, allowing a columnar pattern of cracks or joints to develop due to contraction/shrinkage during cooling; the columns forming at right-angles to the cooling surface. A very rough analogy would be the polygonal pattern produced in mud, due to shrinkage, in a dried-up pond; although this phenomenon only affects the surface layers of the mud and occurs on a smaller scale. Visitors to Ireland, even those with no particular interest in geology, should have the Giant’s Causeway high on their list of ‘must see’ places.
ASPECTS OF IRISH GEOLOGY EXPLAINED — SIMPLY
Uses of Antrim Basalt
The basalt has long been quarried for use as aggregate, for the preparation of concrete, and for foundations of roads and buildings. To a lesser degree it has been employed as a building stone. With the exception of the Crumlin Road Jail and Clarendon Dock, it was not used extensively in central Belfast. However, it can be seen in the walls surrounding many buildings, particularly church buildings, in north Belfast. Also, it had widespread use in rural areas for drystone walling and the construction of farm outhouses. A view of the Cavehill as seen from north Belfast. It is mostly composed of basalt around 60 million years old.
Localities
Co. Antrim Basalt. Age: around 60 million years old (Early Palaeogene). There are quite a few places in Co. Antrim to see good examples of this basalt in situ. Some are: (1) Cavehill (in the area around the caves), north Belfast; (2) Blackhead, about 2km NE of Whitehead (follow the tourist path from Whitehead); (3) Craig’s Quarry, Glenwherry, Ballymena; (4) Tully Quarry, Moorfields Road, Ballymena; (5) Ballylig Quarry, Broughshane; (6) Clinty Quarry, Doury Road, Ballymena and (7) J. Boyd’s Quarry, Mallusk Road, Newtownabbey.
Antrim Basalt (mostly weathered) used for the wall surrounding Clifton House, at the corner of Clifton Street and North Queen Street, central Belfast.
NOTE: Before entering any working quarry you MUST have permission from the site manager and safety clothing MUST be worn. (Some of the quarries listed here may not be open to the general public.)
Books available from the Spin Store
www.spinstore.eu
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Life’s assembly lines
Tom Kennedy reports on how every cell in our body has thousands of tiny machines squirting out all the proteins that enable us to live.
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e need our proteins. The haemoglobin that carries oxygen to the lungs, and the rhodopsin that enables us to see are just two of up to about 20,000 different types on which we depend on for structure, regulation and function. Without the most abundant, collagen, consisting of three strands braided like hair, we could have no skin, cartilage or connective tissues to keep us in shape. The master plan for making up these proteins resides on our DNA, and as the 2009 Nobel Prize Winner, Venki Ramakrishnan explained, the translation process from code to protein is a bit like going from a four to twenty letter alphabet. The DNA code consists of just four nucleotide units, adenine, cystosine, guanine and thymine, and these are transcribed into closely related RNA with one difference in that thymine is replaced by uracil. While the DNA has the master plan, the RNA passes on the message, packaged into groups of three nucleotides, known as codons. The codons are like the letters in an alphabet that can be combined to spell out 20 different amino acids, and by combining these 20 amino acid words in different ways thousands of different proteins can be created. Each can have from about 200 to 35,000 amino acids arranged in a
complicated folding chain. Although scientists had a good idea of what was going on, said Venki, the first part of unravelling the puzzle was to determine where synthesis of proteins takes place. After observing what looked like little blobs when cells were examined under the electron microscope, scientists were able to identify these as the ribosome sites of protein assembly. Bacterial cells have thousands of these production sites and, our own more evolved eukaryotic cells can have millions. The ribosomes are like factories busy churning proteins out into a maze-like network of distribution channels. For Venki Ramakrishnan, knowing where protein production takes place was one thing, but the next challenge was to work out how the ribosomal machinery works. Venki had originally been a physicist, and this question drew him into applying his knowledge to biology. In order to understand what’s going on in a biological system, he said, you need to go way beyond the resolving power of ordinary light microscopes, and to record functional structures at an atomic level it
An outline of how amino acids are brought in by tRNA to match up with the mRNA codons. The amino acids join up within the ribosome and emerge as a protein chain which then folds into complex shapes.
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Ribosomes are extremely complex and determining their structure at an atomic level was a huge challenge. is necessary to use X-ray crystallography. X-rays have much shorter wavelengths, but they are also so energetic that they damage the objects being examined. To overcome this problem the materials to be examined are crystallised and cooled in liquid nitrogen. The scattering of X-rays form a pattern that can be reconstructed as an image of the molecular structure. The technique, developed first in 1912, is not new, it was used to reveal the DNA double helix, but the technology has advanced considerably over the years. Extremely powerful rays from a synchrotron can be used and there is a lot Earlier this year the Nobel Prize winner, Venki Ramakrishnan from the MCR Laboratory of Molecular Biology, Cambridge, was in Dublin to present prizes to three young winners of a DNA RNA writing competition organised by Prof John Atkins and the West Cork Education Centre. During the prize-giving ceremony Venki talked about how the complex machinery of protein production was unraveled. Every cell in our body has thousands of these little ribosomal factories, and by understanding how they work scientists may win the race against the rise in antibiotic drug resistance.
more processing power available now to interpret the results. In a way, said Venki, what scientists are doing with X-ray crystallography is similar to how we see the objects around us. Our eyes sense the rays of light reflected from our surroundings and our brain interprets this information as sight. In a similar way, the X-rays scattered from an object can be collected and processed into an image by computer. While this approach provides scientists with an image, this is not the atomic structure, said Venki. Working out the atomic structure, he said, is a bit like doing a very complicated jig-saw with some parts missing and no picture on the box to act as a guide. There are parts that cannot be seen and there are pieces that may as well have fallen in from another box, and on top of this the structure is in three rather than just two dimensions. Tackling this task is a daunting challenge, but as Venki said, like a complicated jig-saw puzzle, you begin with one or two bits that seems to make sense. Then, by zooming in, a few more pieces might fit in. “You poke around until you see features that you can recognize,” he said, and then zoom back out to begin somewhere else. Using this approach Venki, Tom Steitz and Ada Yonath worked out the atomic structure of the ribosome in 2000. This was a huge achievement, earning the three the Nobel Prize, for the proteinmaking machine is made up of almost a million atoms. The ribosomes are made up of two distinct parts, one a little bigger than the other, and to the surprise of the scientists, who expected a structure composed entirely of RNA, they found that some proteins were present. In bacterial ribosomes there were about 50 proteins, and in human cells, about 80, so, as Venki commented, here we have another puzzle for scientists to solve. How is it that a machine that produces proteins is itself partly made up of proteins? In this there is a parallel to an assumption previously held about RNA, which was originally thought of as just a messenger, but we now know that this is not the case, different types exist, and in fact RNA may even have evolved before DNA. Early ribosomes may well have consisted of RNA, and as soon as they started to make proteins, some stuck. By working out the detailed structure of the ribosome, it finally became possible to understand how the machinery works. Three different types of RNA are involved, ribosomal RNA (rRNA),
Our current approach to developing drugs is wrong and if we don’t change this, the battle against rising resistance will be lost.
Venki Ramakrishnan points out that by understanding how the ribosome works we can develop more effective antibiotics. messenger RNA (mRNA) and transferase RNA (tRNA). As the mRNA, arrives at the ribosome with a long string of bases, arranged in three letter codons, the tRNAs are on standby with a delivery of amino acids ready for assembly. One end of the mRNA has a codon which acts like a start button, and as the string feeds into the ribosome, the tRNAs that match the three base codons latch on, inserting the appropriate amino acid. As the mRNA string continues along through the ribosome, the tRNA with its amino acid is pushed up before the two part company. The used tRNA is cast out, and the amino acid is fed into a tunnel where the rRNA acts as a catalyst in creating a peptide bond linking it as next in line to the end of a growing protein chain. When the mRNA reaches the codon that tells it to stop, the long protein chain is set free to begin its journey to the final destination. Normally we want to ensure that this machinery continues to work perfectly, but in the case of infectious bacterial diseases, we use antibiotics to disrupt the process. Each step in this protein production process is of critical importance, and with antibiotics we are able, in effect, to throw a spanner in the works. Essentially the ribosomal machinery in bacteria and higher cells is similar, but antibiotics are more selective in blocking the bacterial version. Some antibiotics only have a small number of atoms, but even so, they can disrupt bonding so that peptides can no longer form a chain. Others can sit at the entrance of the tunnel, and Venki
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compared these to having an object stuck in a door hinge. When antibiotics were first developed they were greeted as the ‘miracle drugs’ that would clear up many of the world’s worst infectious diseases. As a reminder of just how serious these diseases were, Venki said it is remarkable how many of the great achievers in science died young. All, he added, died from infectious diseases. With antibiotics these brilliant people and millions more would have enjoyed longer lives. However, as we now know, antibiotics have a limited life. Infectious bacteria fight back. Like all living things they have survived by adapting, and bacteria in particular have an extraordinary ability to pick up and exchange useful tools, including those that enable them to overcome the barriers thrown up by antibiotics. When penicillin was introduced in the 1940s it was completely effective against the bacterium, Staphylococcus aureus. Within two decades nearly all hospital strains had become resistant, and now resistance is universal. Switching over to another antibiotic is just a temporary solution, and the more generous we are in treating every infection with antibiotics the worse it gets. Pathogens have acquired multi-drug resistance, and the so called ‘superbugs’ are killing 25,000 people a year in Europe alone. The old killer, tuberculosis, is becoming harder to treat, and globally it is causing two million deaths a year. As Venki pointed out, by understanding the details of what’s going on in the ribosome, we can do something to slow down or even halt the rise of drug resistance.
On that point Venki Adding to our limited “It’s funny how stock of antibiotics had an interesting we all start off as story to tell about how and using them with a company, Rib-X greater precision scientists. When we Pharmaceuticals, would help. are children we are had been making However, as Venki observed, “drug considerable progress all naturally scientists in developing companies do not because we ask ribosome-targeted like antibiotics.” The antibiotics before being cost of development is questions.” abandoned by investors. high and if better drugs The company, was set are developed, people will only use them once, he said, so up by researchers at Yale to apply this new-found knowledge to the financial incentive is low. From develop more advanced alternatives to an industry perspective, commented antibiotics such as erythromycin, which Venki, someone who has a combination are becoming less effective against acute of chronic diseases so they have to pop some pills every day for the rest of their infections because of resistance. One of the basic weaknesses of the lives is a good customer. existing antibiotics is that they knock In Venki’s view, the current approach out one link and it is relatively easy for to drug development is wrong and it disease-causing bacteria to get around needs to be reformed. It is possible, that problem. So, instead of targeting just he said, to develop new and better one step, as with existing antibiotics, the antibiotics, but if we don’t change our company synthesized a compound that approach, the battle to stay ahead of acted on two sites. As Venki explained, rising resistance will be lost.
this approach was very successful, the compound was found to kill all resistant strains. However, designing and making a drug, he explained, is just one side of the story. There are many reasons why a potentially useful drug can fail to reach the market, so on top of the initial investment to fund research, money has to be found to conduct clinical trials and work out effective forms of delivery. About two years ago, said Venki, Rib-X Pharmaceuticals attempted to raise this money by going public, but, unfortunately, the shares commanded too low a price, so the offer was withdrawn. As Venki pointed out, here is a company developing a product that could have solved enormous problems and saved hundreds of thousands of lives, yet a business involved in sharing of photo snaps can be worth over one hundred million dollars. “There is something screwy about this,” he remarked. There is something seriously wrong with our priorities, he said when this sort of thing happens.
Details about the next DNA/RNA competition for schools will be available on the West Cork Education website — www.westcorkeducationcentre.com
Growing young entrepreneurs
A line up of winners, from left, Hayley Todesco from Canada for her project on breaking down pollution, Mihir Ganimella from the US for his flying robot, Kenneth Shinozuka from the US for his wearable sensors, and the Irish team, Ciara, Sophie and Émer.
Google winners
WInneRS of the 2013 BT Young Science competition, Ciara Judge, emer Hickey and Sophie Healy-Thow, have topped the Google Science Fair. After competiting against young scientists from more than 90 countries the three students from
Kinsale Community School, County Cork were presented with the award at Google’s headquarters in California. After months of research, the three students found that root-dwelling bacteria boost the growth of important food crops such as barley by up to 70 per cent.
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In a bid to increase the number of startup businesses, entrepreneur awards are being offered to third-level students by enterprise Ireland and Invent nI.With an overall prize fund of €35,000 the top award for submissions is worth €10,000 plus €30,000 for consultancy. The awards for 2015 are being supported by Cruickshank Intellectual Property, Grant Thornton and Intel, and are open to all third-level students throughout Ireland. Last year Darren O’Connor from University of Limerick won an award for his joing rehabilitation system, and Dr eric Risser from Trinity College Dublin received his award for annimation software that makes it easier and cheaper to produce artwork. The closing date for entry is 17th March 2015. More information about the awards at www.studenterepreneurawards.com
Aurora Borealis over Alaska viewed from the International Space Station
SUN STORMS
ANDFranklin THE NORTHERN LIGHTS Margaret explains why the night sky lights up when Earth is showered by charged particles from the Sun
S
ince the beginning of 2011, sunspot activity has been on the increase, triggering geomagnetic storms and giving rise to spectacular displays of the Northern Lights. Normally these lights, also known as the Aurora Borealis, are only visible from at extreme northerly latitudes such as Norway, Finland, or the north of Scotland. However, spectacular auroral displays were observed in February 2014 from parts of Donegal and even as far south as Sligo. It is quite rare for the Northern Lights to be visible from Ireland, so why are they being observed now, in this country? The Sun has an eleven year cycle, alternating between active phases and less active phases. Even in its quieter phases, the Sun is seething with activity. Like all stars, it is a massive ball of extremely hot gas, held together by gravity. Unlike the gases in earth’s atmosphere, this gas is not composed of molecules, but of ionised atoms. These are atoms that have had their negatively-charged electrons ripped off by the intense heat, exposing the positively-charged nuclei. Most of the material of the Sun consists of the element hydrogen. The nuclei of
The Aurora Borealis and the Manicouagan Impact Crater reservoir (foreground) in Quebec, Canada, in this photograph taken by astronaut Donald R. Pettit on board the International Space Station. hydrogen atoms are tiny charged particles called protons. Such a hot ionised gas is known as plasma. We have three states of matter on our planet earth; solid, liquid and gas. Plasma is a fourth state, that occurs only at extremely high temperatures, such as in the stars. The Sun’s gravity produces enormous pressure in its centre and this, along with the high temperature, causes thermonuclear fusion to occur. In this process, four protons fuse to form helium nuclei, releasing enormous amounts of energy. The mass of a helium atom is slightly less than the combined masses of four protons. A great amount of
In the southern hemisphere, Aurora Australis appearing in the night sky at Swifts Creek, 100km north of Lakes Entrance, Victoria, Australia. Photo: Flagstaffotos
energy is produced because the missing mass is converted into energy, according to Einstein’s famous equation E = MC2. It is thermonuclear fusion which generates the Sun’s energy. In the interior of the sun, the temperature is much hotter than at the surface. This temperature difference causes convection currents, while the Sun’s rotation makes the plasma swirl around, with different parts of the sun rotating at different speeds. This turbulent motion of charged plasma creates strong fluctuating magnetic fields, whose lines of force create loops in the sun’s outer atmosphere, known as the corona. Closed magnetic loops cause a slight cooling in places, which appear as darker sunspots on the bright surface. When the sun becomes more active, more sunspots appear. When the magnetic fields are stable, they confine the plasma. But as energy builds up, an intense burst of radiation, known as a solar flare, can occur. The magnetic loops sometimes break, behaving rather like the rubber band in a catapult, releasing up to a billion tons of material in what is known as a coronal mass ejection (CME) which sends streams of charged particles (protons and electrons) out into space. If such an event occurs on the side of the sun facing earth, the charged particles may enter our earth’s atmosphere The earth’s magnetic field acts as a shield, protecting most of the earth from these charged particles, which are directed along the lines of force of the field, which converge towards the north and south magnetic poles, so that most of the charged particles enter the atmosphere above the poles. There they interact with molecules in the earth’s atmosphere, producing beautiful curtains of light in the sky, which we refer to as the ‘Northern Lights’ or Aurora Borealis in the northern hemisphere. The same phenomenon is known as the Aurora Australis when observed near the south pole. The light is emitted when electrons in the oxygen and nitrogen molecules return to their normal or ‘ground’ state, having first been ‘excited’, that is, raised to higher energy levels, by the interaction with the charged
Northern Light over Malmesjaur lake in Moskosel, Lappland, Sweden. Photograph: Jerry MagnuM Porsbjer
Hakoya island, Norway. Photo: Frank Olsen
Eielson Air Force Base, Alaska — The Aurora Borealis above Bear Lake
SCIENCE SPIN Issue 64 Page
particles from the sun. An aurora is observed as a green or sometimes red glow in the sky, which may look like wispy threads of light, or luminous curtains in the night sky. The aurora slowly changes its shape and it can be a really stunning sight. The magnetic storms caused by solar flares are not harmful to humans on earth, but they can disrupt satellite and radio communications and occasionally they can interfere with power distribution. If the magnetic surge is very strong, it could possibly induce electrical currents and burn out transformers. The radiation hits the upper atmosphere and does not penetrate any lower than about 100 km above sea level. The light that is emitted is quite safe. However, the astronauts on the International Space Station (ISS) could be at risk from the solar ‘wind’, so there is a special area inside the ISS for crew to shelter from sun storms. So far, our national grid has not been affected by the increase in solar activity. We get advance warning of geomagnetic storms, because the visible light and other electromagnetic radiation from the solar flares travel at the speed of light, reaching earth in eight minutes and can be detected by NASA and other space agencies. The material particles released during the coronal mass ejection do not travel quite as fast and take a day or two to reach our atmosphere, so it is known a couple of days in advance, when to expect these storms. This is what caused the amazingly brilliant display of the Northern Lightsin February 2014, allowing them to be seen much farther south than usual, even in Donegal! There are likely to be more coronal mass ejections and auroral displays in the coming months. To see them, we need to look towards the northern horizon on a clear night at a dark location, away from public lighting, and as far north as possible. More information about solar activity may be found on this website: http://www.thesuntoday.org/tag/coronal-mass-ejection/
Aurora image taken at Hillesoy island, Norway. In the distance the light from the city of Tromsø (Tromsoe) shines in a faint orange color. Photo: Frank Olsen.
Red and green Aurora in Fairbanks, Alaska. The unusual formation was at first thought to be due to the presence of a nearby star, but now it is understood to be a region where dust can build up into larger objects, thus beginning planet formation. To give an idea of scale, the orbit of Neptune is shown.
Dust traps
PLANeTS form from the dust around stars, but as scientists are not sure of how this happens. One of the mysteries that has been puzzling scientists is how larger particles manage to stay in orbit instead of falling back into the parent star. By the time particles have managed to clump into metre sized bodies computer modelling suggests that they should start falling back into the star. Another problem is understanding how larger
bodies can remain intact when constant high speed collisions would be expected to reduce them back into dust. Astronomers observing a young star, 400 light years away from earth, may have found some answers to these questions. A team of astronomers, led by Nienke van der Marel from Leiden Observatory in The Netherlands, observed an unusual formation of dust around the star located in the Serpent Bearer constellation using the giant Alacama Large Millimetre/submillimeter Array (ALMA) telescope in Chile. The One of the team members, Dr Vincent Geers from the Dublin Institute of Advanced Studies explained that instead of a symmetrical ring of dust, they observed a crescent-shaped cloud. From this, the astronomers concluded that some regions can become ‘dust-traps’ allowing objects to grow. These regions, he said, could be thought of as some kind of vortex where particles of dust can stick together forming objects that continue to grow until a few kilometres across. The observations were made while the telescope, situated at high elevation in Chile’s Atacama desert was still under construction. Dr Geers said that now that the full array of the ALMA telescope is coming into operation, astronomers should be able to see a lot more, and may even be able to observe planets forming.
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FAMILY SCIENCE
With Christine Campbell
Welcome back to Family Science. In this issue we are discussing crystals and have lots of ideas for growing your own. We welcome your feedback, photos of any of your experiments that you have tried at home, what worked and what didn’t.
Crystals and Crystallography
Growing crystals can be magical for children! Often young children think that if they dissolve a solid such as sugar or salt in water that the salt or sugar has gone. When I make salt water with children for use in an experiment they often tell me that their salt has gone and that they need more for it to be salt water again. When I tell them that the solid will reappear when the water evaporates that meets a lot of scepticism. Of course if you try this you will find that the water does in fact evaporate and leave the solid behind. Not only will the solid be left behind, but the solid that appears after dissolution will mostly consist of much larger particles than those you started with. Another interesting aspect of growing crystals is that different chemicals have characteristic crystal shapes. For example table salt, sodium chloride, forms cubic crystals whereas Epsom salts, magnesium sulphate, forms long needle-shaped crystals. 2014 is a special year for crystals – it has been designated the international year of crystallography. Crystallography is the science that examines the arrangement of atoms in solids. It is approx. 400 years since Keppler noticed that ice crystals are symmetric and 100 years since X-ray diffraction allowed the detailed study of crystalline materials.
Experiments with Crystals — Sodium Chloride Suitable for doing with the youngest children, growing sodium chloride crystals can be very satisfying. Most families will have everything they need for this experiment in the cupboard. Sodium chloride crystals have a characteristic cubic shape. To grow sodium chloride crystals you will need: l Small beaker capable of measuring less that 100ml water l Sodium Chloride (Table salt) l Sticky tape l Paper or your science diary l Ruler l 2 Teaspoons l Warm water l Coffee filter l Funnel (if possible) l Plastic tray such as a lunch box or disposable plastic tray. l Adult supervision
What to do:
l Sprinkle some salt onto a piece of paper or onto a page in your science diary. Stick them down with sticky tape so you will have a record of what you started with.
Other Crystals
l Heat the water to approx. 4555°C. You could just use water from the hot tap. l Taking care not to get scalded, measure out 50ml of water. l Using one teaspoon, add a spoonful of salt to the warm water. l Using the second spoon, stir the salt and water mixture carefully until the salt all dissolves. l Add another spoon of salt and stir until the salt has dissolved. Continue to add salt, spoon by spoon, until no more will dissolve. l Insert the coffee filter into the funnel and filter the salt solution. Collect the filtrate (the liquid) in the plastic tray. You need to be very patient while this is happening. l Discard the coffee filter and whatever has collected in it. l Leave the tray uncovered in a warm dry place, a sunny window ledge is ideal. l Check every hour for the first day and once or twice a day for the next few days. The water will evaporate and salt crystals will grow. l Remove the larger crystals from the tray and stick samples into your science diary. Measure and record their size.
Other crystals that are interesting to grow at home are Epsom Salt (Magnesium sulphate) crystals. Magnesium sulphate forms long needle shaped crystals. Follow the procedure for sodium chloride replacing the sodium chloride with magnesium sulphate. An interesting thing to do is to count how many spoons of solid dissolve in the 50ml of water and compare your result with the number of spoons of salt you were able to dissolve. Don’t forget to make sure your test is fair. You should check that things like the temperature of the water are the same at the start of both experiments. Magnesium sulphate is one of the ingredients of bath salts. People use bath salts to help them relax. Athletes use it to soothe sore muscles. It is also used on people and animals to help cuts heal faster.
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Synthesise and crystallise Rochelle Salt Sometimes when you mix two things together what scientists describe as a physical change occurs. In a physical change only the appearance changes, after the change you still have the same materials just in a different form. An example would be where water freezes and turns to ice. Ice is just frozen water. Another example is dissolving salt in water. The salt is still there. The particles have just divided up into much smaller units. Physical changes can easily be reversed – you can melt ice and it turns back to water. You can evaporate the water from a salt solution and get the salt back. There are other materials that when you mix them together they react and new materials are formed. Scientists call this synthesising a material. In this experiment we are going to start with 2 materials – Washing Soda (Sodium Carbonate) and Cream of Tartar (Potassium Hydrogen Tartrate). If you dissolve these two materials in warm water they react to make Potassium Sodium Tartrate (Rochelle Salt), Water and Carbon Dioxide. When the water evaporates very large Rochelle Salt crystals grow. Rochelle salt has numerous interesting properties and uses. As I mentioned above it form very large crystals. These crystals are piezo electric which means that when they are pressed they produce an electrical voltage. This means of producing electricity is currently
Royal Society of Chemistry Global Experiment Each year the Royal Society of Chemistry runs a global experiment. I would encourage everyone to take part in it. This year it is all about growing large crystals so check it out and share your results here too. http://www.rsc. org/learn-chemistry/resource/ res00001379/global-experiment2014?cmpid=CMP00003401
being investigated as a means of charging batteries in situations where mains electricity isn’t available. The same Rochelle salts are used as a food additive to give a cooling effect in foodstuffs. They have an E number – E337 so check out the ingredient lists of your food to see which ones contained it. You will need: l 36g Washing Soda l 47g Cream of Tartar l Weighing scales l Dishes or plastic cups for weighing l 2 500ml beakers or jugs l A saucepan l Heat source such as a cooking hob l Spoon for mixing l Funnel l Coffee Filter l Plastic tray such as a lunch box l Adult supervision What to do: l In the saucepan heat water to almost boiling (approx. 90°C). l Measure 50ml water into the 500ml beaker. Don’t forget 1ml water
Rochelle salt
weighs 1g so you can always weigh it if you don’t have graduations on your beaker. Stand the beaker in the water bath to heat the water. l Weigh out 47g of cream of tartar and add it to the heating water. l Weigh out 71g of washing soda and add it very slowly to the hot water stirring the mixture after each addition and waiting until the bubbles subside to add more. This reaction takes in heat from its surroundings so continue to heat your water bath. l Once the reaction has finished – you will know that it is complete when the bubbling stops, set up a funnel lined with filter paper and filter your mixture into a clean beaker. l Pour the filtrate into a plastic tray and leave uncovered in a warm dry place. l Check for crystal growth regularly over the next few days. l Remove large crystals and leave to dry.
Here are some photos of Rochelle Salt crystals that I grew recently. My largest one is 23mm long and 19mm wide. Do let us know how you get on and send us photos of your largest crystals.
Science Week
Starting November 9th 2014 This is a week packed with science activities all across the country. Many schools run special events and there are numerous science and technology festivals taking place across the country. Over 100 events are listed on the science week website so you are bound to find something in your area. Discovery, Cork’s Science Festival, is one of the biggest events of Science Week Ireland, with a 2-week programme of events for families, schools and youth groups.
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At the interactive exhibition in midNovember, families and school groups can enjoy exploring science, technology, engineering and maths by having fun - making teddies dance, constructing periscopes, and solving puzzles. Well worth a visit if you are in the Cork area.
Christine Campbell Anyone 4 Science anyone4science@eircom.com www.anyone4science.com
Sive Finlay introduces us to the Barnacle Puppet Master
Weird and wonderful animals
P
arasites are everywhere. They have evolved a whole host of weird and often disturbing ways to eke out a living from their host. Some parasites are relatively harmless; they take what they need and move on. Others have more sinister tactics in which they take over the host’s body entirely and manipulate it to serve their own purposes. Sacculina carcini is one such puppet master. It is a parasitic barnacle which infects green crabs (Carcinus maenas, the common shore crabs found on any Irish beach). As an adult, Sacculina doesn’t look like the barnacles which are familiar features of our rocky shores. Instead, they resemble large, bulbous masses of reproductive cells which bulge out from the crab’s abdomen. Charming! Sacculina starts life as a freeswimming, planktonic larva (a mobile stage which it has in common with other barnacle species). When a female larva finds a crab host, she “walks” along the crab’s hard shell until she finds a small chink in the armour at a leg joint. The larva then injects a sluglike mass of cells into the crab. The alien invasion has begun. Once inside the crab’s body, Sacculina grows a web of root-like tendrils which wind their way through the crab’s body cavity. They go everywhere: around the digestive system, nerves and they even surround the crab’s eyestalks. The tangled web not only gives Sacculina access to food nutrients from the crab’s digestive system but it is also an important control network. Infected crabs are at the mercy of their parasitic masters. Sacculina takes control of the crab’s hormonal and nervous system with dramatic consequences. The crab becomes a different type of animal: one whose only purpose is to serve the needs of its parasite. Sacculina stops crabs from growing so that it can direct all of that extra energy towards its own reproduction. Furthermore, the parasite castrates its host and instead co-opts all of the crab’s parental instincts for its own devices. When male Sacculina larvae come in contact with an already parasitised crab, they inject their own cells into the slug-like female Sacculina and fertilise her eggs. At this stage, infected crabs
develop a large mass predators that can have Female Carcinus maenas crab significant impacts on of parasite eggs in their with the eggs of Sacculina abdomen. If the crab both natural ecosystems carcini. host is male, Sacculina and commercial fisheries. Photo: Wikimedia commons. will control its hormonal Some researchers have system so that it develops suggested that Sacculina female characteristics carcini should be including a wider abdomen deliberately introduced which is more suitable into invasive green crab for incubating eggs. populations to limit their The crabs incubate the numbers. parasite’s eggs until they However, initial hatch into free larvae. experiments have Seemingly unaware that shown that Sacculina their “offspring” are not also infects other crab their own, infected crabs species so introducing continue to exhibit their the parasite could have normal parental behaviour. negative impacts on They climb to high places native crab populations. with fast flowing currents Current research is trying and disperse the parasite’s The larva seeks out a chink in to establish whether larvae as if they were their the crab’s armour and invades potential benefits for own eggs. They even stir controlling green crab to take over. the water with their claws populations outweigh the to help the parasites on their way. How risks of unwanted impacts on other crab about that for serving your master! species. Whether this insidious parasitic Sacculina are clever, weird and ever so puppet master can be tamed to act as a slightly disturbing. However, aside from pest control remains to be seen. their apparent roles as an evolutionary villain, Sacculina could be useful as biological control agents. Carcinus maenas Sive Finlay, a Zoology graduate, is currently crabs have spread beyond their natural working as a postgraduate scholar with the range to become unwanted, invasive Macroecology and Macroevolution group at species in North America, Australia Trinity College Dublin. and South Africa. They are voracious
SCIENCE SPIN Issue 67 Page 28
BT YOUNG SCIENTIST AND TECHNOLOGY EXHIBITION Saoirse O’Reilly, Aisling Murphy and Nicole Devitt with their freshwater system.
water is so scarce that little can be spared for irrigation. The students thought that evaporating seawater and collecting the condensed freshwater would help solve this problem, but as they argued, the solution has to be low-tech and inexpensive for it to be of use to people with limited
resources. The idea of evaporating water, they said is not new, but in their project all they had to use were ordinary plastic (PET) containers. Discarded in their thousands, yet ideal in that they are transparent and contaminant free. To make the device, tops were cut off, and a larger container placed over a smaller one filled with seawater. As the seawater evaporates, the salt is left behind, condensation forms on the outside and runs down for collection at the bottom. Saoirse, Aisling and Nicole said they got great encouragement from their teacher, John O’Brien, and also from the nuns who run an ecology centre next to their school. In tests, the students said they had no problem keeping their tomato plants watered, and they concluded that if this system works well in Ireland, results would be even better in countries such as Tananzia and Somalia. As long as there is seawater and heat from the Sun, they said the simple system works, and it would be easy to scale up. Just get bigger containers, they said.
The situation, they said, can be worse in rural areas, and where organic levels are high, trihalemethanes can go over the EPA 100 microgram per litre guideline. The EPA, they explained, monitors these levels, and where they are high, a consultant engineer is sent in to make improvements.
Even if water quality is quite good, where chlorination is being used for treatment, trihalemethanes are going to come through. This made the students wonder if there is some way to remove these chemicals. As they found, simple aeration and agitation can be quite effective. In a test they found that just
Freshwater from the sea Saoirse O’Reilly, Aisling Murphy and Nicole Devitt from the Dominican College in Wicklow observed that many countries suffering from drought have extensive coastlines. However, even if surrounded by seawater, people living in these countries often have to travel long distances to get fresh supplies. Fresh
Downside of chlorination
ADDINg chlorine to our drinking water kills off disease causing bacteria, but as students from the Dominican Convent in galway point out, chlorination has a down side. As Michaela van der Walt, Joanna Orlowska and Aislish Breathnach found when they began to investigate, when chlorine reacts with organic matter, hydrogen atoms are replaced by halogens to produces what are known as trihalemethanes, such as chloroform. These by-products, explained the students, can be quite harmful. Chloroform affects our nervous systems, and over years of exposure to trihalemethanes, we might not pick up a bacterial illness, but we are more likely to develop liver or bowel cancer and kidney damage. In Ireland, most of the water we drink comes from the surface, so it is high in organic matter. Because of this, said the students, chlorination must produce a high level of these harmful by-products. However, they found that while the Environmental Protection Agency has guidelines not much information was available on the subject.
From left, Michaela van der Walt, Joanna Orlowska and Aislish Breathnach
BT YOUNG SCIENTIST AND TECHNOLOGY EXHIBITION passing water from one vessel to another brings down the level of trihalemethanes and boiling results in a further reduction. Boiling, they noted is costly, but they suggested that an ordinary fish-tank pump at the bottom of a tank for aeration could be quite effective. Ailish and Michaela are in fifth year, Joanna is in sixth, and all three are studying chemistry. A lot of what they were interested in, they said, ties in well with the curriculum, and they got great support from their teacher, Dee King, particularly in understanding how to use scientific equipment. At the SciFest the students won the best chemistry award, and they followed this up by entering the BT Young Science and Technology competition. Being involved in the competition, they said is ‘brilliant‘, and they enjoy meeting all the other students and sharing ideas. Coming up with their own project, they added, is so much better than sitting around in a classroom.
European winner
oNCe again winners of the BT Young Scientist exhibition have gone on to distinguish themselves in the european competition. Paul Clarke from St Paul’s College, Raheny, shared the second prize in the eU Young Science competition with students from Bulgaria and Slovenia. Paul was presented with the award at a ceremony in Warsaw for his work on cyclic graph theory. Graph theory involves calculating changing values in a system of interconnecting nodes. The nodes can represent an entity, such as a device within a network of variable values. over one hundred young scientists from all around europe competed for awards in the eU contest. The three top prizes went to João Pedro Estácio Gaspar Gonçalves de Araújo from Portugal, Mariana De Pinho Garcia and Matilde Gonçalves Moreira da Silva also from Portugal, and Luboš Vozdecký from the Czech Republic.
Nathan O’Regan and Sofia Georgieva
Magnetic influence on life LoTS of people would prefer not to live next to power lines, and that made Nathan O’Regan and Sofia Georgieva, fourth year students at Davis College in Mallow, wonder if electromagnetic fields have any influence on living organisms. He came across a report from a Turkish university describing how microorganisms were observed to move towards a negative charge, so they decided to carry out their
own investigations to see what would happen to Paramecium and Amoeba when exposed to a magnetic field. Both are common microorganisms and they are highly mobile. Having obtained a supply of these microorganisms from a lab supplier they placed some on the stage of a microscope attached to a computer screen. Beside this, they set up a circuit, consisting of
SCIENCE SPIN Issue 67 Page 30
Paul Clarke talking about his project to visitors at the BT Young Scientist and Technology Exhibition
a variable resistor, ammeter and a coil around a bar magnet. As they explained, the bar magnet was there to increase the field. As the article they had read reported, the Paramecium and Amoeba were seen to move towards the negative terminal, and increasing the current by 200 milliamps ever ten minutes made them move faster. While it is clear that these microorganisms are influenced by an electromagnetic field, no one has yet come up with a satisfactory explanation for why they do this, they said. As the students suggested, some parts of the microorganisms might have their own charge, and that would make them respond to a magnetic field. At the exhibition, they talked to one of the judges, who raised another question that got them thinking of a follow on experiment to determine if a current alone, without the bar magnet, would produce the same results. As the students observed, there is a lot more to discover on how magnets and electric currents influence living organisms. We can see this at work with Paramecium and Amoebae, they said, but what about the influence on multi-cellular organisms? Observing what happens with singlecelled organisms made them think that multicellular life is also likely to be influenced by magnetic fields. However, that’s something that requires further research, they said.
Dr. How’s Science Wows
Junior science by Dr. Naomi Lavelle
...exploring snow WHAT INFLUENCES THE SIZE AND SHAPE OF A SNOWFLAKE?
HOW IS SNOW MADE?
ke w fla s can b o e sn
als yst r c
A snow flake refers to one snow crystal or a group of snow crystals all grouped together
TRY IT AT HOME... You will need: Borax powder, a jug of boiling water, a plastic cup or glass, some pipe cleaners, scissors, thread or string, a pencil or lollipop stick
Humidity Wind speed
WHY IS SNOW WHITE? The crystalline structure of snow creates many reflective surfaces making the light that falls on it “bounce back” or be reflected making the snow appear white.
CAN TWO SNOW FLAKES BE IDENTICAL? Scientists agree that the exact shape and structure of each natural snow crystal is unique – so that means no two snow flakes O T TO COL are GE NO, once D identical there is enough water vapour and circulating air then snow can be made at very low temperatures!
W? SNO
What is happening? When we heat the water it can dissolve more powder than when cold - we call this a saturated solution! As the water cools it cannot hold all that extra powder and the borax comes out of solution. This time it comes out as a crystal and not a powder and these crystalsform on the decoration.
Air temperature
TO
What to do: Keep adding borax powder to the boiling water and stir it in until no more will dissolve. Make your decoration out of the pipe cleaners, it needs to be small enough to fit into your plastic cup without touching off the sides. Tie some thread to your decoration and hang it from the lollipop stick and place it across the top of the cup so the decoration hangs down without touching the bottom. Pour the borax solution into the cup making sure you cover the pipe cleaner shape completely. Leave overnight and the next day your decoration should be covered in crystals. Remove it from the cup and leave to dry.
How far the snow flake has to fall
IT
Som e
How high up the cloud is
CAN
A snow crystal is a single crystal of ice that can come in many different shapes.
Dirt and dust particles
s of tiny snow red
WHAT IS THE DIFFERENCE BETWEEN SNOW CRYSTALS AND SNOW FLAKES?
Cloud temperature
de up of hun ma d
Snow is made much in the same way as rain, it is created from the moisture that makes up clouds. Moisture from the earth (seas, rivers, lakes, puddles etc) is constantly EVAPORATING (changing from a liquid to a gas form). This water vapour (gas) is picked up by warm air and carried to the sky where it forms clouds. When the temperatures get cold enough the water vapour turns into ice crystals that form around tiny particles of dust or dirt in the atmosphere. These ice crystals fall to the earth as snow.
If you want to know HOW something works why not write to Dr. How and ask? Send your e-mail to naomi@sciencespin.com
Ask a scientist
More than 25 experts from a wide range of fields including biology, physics, chemistry and astronomy are ready to answer your questions. If there is something that puzzles you, let the panel know. Email questions, with your name and contact to
question@sciencespin.com
Why does striking a flint produce a spark?
How do nettles sting?
Look closely and you see that leaf edges have hair-like projections. These are hollow and the base has a sac filled with irritating chemicals. The tips are brittle and easily break off to release the contents. Because the broken edges are sharp they puncture the skin and bending the hairs makes the irritating chemicals squirt out.
Joseph Cashell explains — When you strike the flint, tiny fragments of metal (usually magnesium) are knocked off it and the friction of the strike generates enough heat to ignite the fragments appearing as a ‘spark’ to the human eye. l Joseph Cashell, Tyndall National Institute. www.tyndall.ie
A close up of the stinging hairs. Photograph:Jerome Prohaska
How deep can mines go?
Niall Boohan explains — Theoretically there isn’t anything stopping you from drilling through the Earth, but temperature increases the further you go down. This is mainly from the heat released from radioactive decay, but also heat is generated by the force of Earth’s gravity. The temperature increases about 15°C per km you travel down into the crust. Because of this, unless you pay for expensive cooling equipment, about 2km is the limit. To go beyond this requires a big investment in engineering to overcome the heat. l Niall Boohan, Tyndall National Institute. www.tyndall.ie According to Mining Technology, the Mponeng gold mine, near Johannesburg in South Africa holds the record for depth, extending 3.9km below the surface. Cooling reduces the 55°C heat down to 28°C but rock surfaces can reach 60ºC, so working conditions are extremely difficult. The TauTona gold mine in South Africa comes a close second with a similar depth. The Savuka gold mine, also in South Africa comes third, with a depth of 3.7km. Other extremely deep mines are: Savuka Gold Mine, South Africa, 3.7km Ground 20ºC Driefontein Mine, South Africa, 3.4km Kusasalethu Gold Mine, South Africa, 3.2km Moab Khotsong Gold Mine, South Africa, 3km 1km 35ºC South Deep Gold Mine, South Africa, 2.9km Kidd Creek copper and zinc mine, Ontario, Canada, 2.9km Great Noligwa Gold Mine, South Africa, 2.6km 2km 50ºC Creighton Mine, Ontario, Canada, nickel, 2.5km
Is it true that the Moon is moving away from Earth?
Joseph Cashell explains — As you may know, the Moon is responsible for the ocean tides on Earth. This occurs because the Moon’s gravity pulls on the Earth’s oceans as it orbits causing them to swell and drop.
However, as the moon pulls on the Earth causing tidal effects, the Earth also pulls back, causing the Moon to slow down. The slower an orbiting body is, the larger it’s orbital radius is so as the moon slows down it’s getting further and further from the Earth. l Joseph Cashell, Tyndall National Institute. www.tyndall.ie
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The Moon reflects sunlight. The Sun is yellow, so why is the Moon white?
Joseph Cashell explains — The Sun is white and so is the Moon. The reason the Sun appears yellow is the same reason the sky is blue. The white light leaving the Sun is made up of the visible spectrum i.e. the colours of the rainbow. As the white light enters the atmosphere, the shorter wavelengths of light like violet, indigo and blue are scattered throughout the sky making it appear blue. However, the longer wavelengths like red, orange and yellow remain unscattered and come in a straight line from the Sun to your eye which is why you see a yellowish colour. When you look at the Moon you’re seeing the Sun’s light reflecting off of it so it should also appear yellow. When you see pictures of the Moon taken from space the true colour, white, is seen.
Where does uranium come from and how much is there?
Niall Boohan explains — Uranium like all heavy elements, is produced by supernovae (exploding) ancient stars. If you took our Sun as an example, it consists of mostly hydrogen and some helium and tiny amounts of the elements; lithium up as far as carbon. Our Sun is a fusion reactor Margaret Franklin explains — Uranium occurs widely in many rocks and minerals in the earth’s crust. It has roughly the same natural abundance as tin and occurs in trace amounts in rocks such as granite and is also present in seawater. At the moment, it is not economic to extract uranium from the latter source. Most uranium comes from mines in Australia, Canada and Kazakhstan, with smaller quantities being mined in the United Sates of America, Russia and some African countries. Very high-grade ores can contain up to 20 per cent of uranium.
for all intensive purposes. The force of the Sun’s gravity on the hydrogen atoms causes them to travel at enormous speeds and crash into each other with enormous energy, so much in fact, that their nuclei stick together and form helium atoms. When very large stars run out of hydrogen and helium they explode releasing even greater amounts of energy for short periods of time. It’s this short burst of ferocious amounts of energy that
stick the light elements like lithium and helium together to form that much larger elements like uranium. I’m not sure how much uranium there is in total but there’s about 3 micrograms in every cubic metew of water on the Earth’s surface (1340000000000000m3) which is a lot of uranium!
Ores with approximately 2 per cent uranium are classified as ‘high grade’, while ‘low grade’ ores may contain as little as 0.1 per cent of the metal. It is difficult to say how much uranium is there, because not all potential sources have been discovered as yet. Known uranium resources have tripled since 1975 and as more exploration takes place, more ore deposits are being found. Recent reports show that Australia has about 30 per cent of the world’s uranium resources, or about 1.67 megatons, while Kazakhstan has about 12 per cent (650 kilotons approx.) It is estimated that known
global resources would be enough to provide fuel for the world’s nuclear reactors for the next 200 years. Apart from the direct sources, uranium for nuclear fuel can be obtained from several indirect sources, including reprocessed spent nuclear fuel, recycled uranium from decommissioned nuclear weapons and stockpiles of depleted uranium.
Hydrates under the sea are supposed to lock up a lot of methane, so could we make use of these as a source of energy? Margaret Franklin explains — Methane hydrates are ice-like solids belonging to a class of compounds known as ‘clathrates’. Clathrates are defined as “Inclusion compounds in which the guest molecule is in a cage formed by the host molecule or by a lattice of host molecules.” (International Union of pure & Applied Chemistry) The clathrate cage may consist of a single large molecule, often a polymer, which has a cavity inside it big enough to hold a smaller molecule. Alternatively, the cage may be made up of small molecules linked together. In the case of methane clathrates, the cage is of the latter type; consisting of water molecules held together by hydrogen bonds. Methane clathrates are unstable at normal ambient temperatures and pressures. They are formed at very high pressures and low temperatures (close to the freezing point of water) and occur under the permafrost in polar regions and on the sea bed near the edges of continental shelves. If allowed to warm up at atmospheric pressure, the clathrate breaks down. The ice cage melts to form liquid water and methane gas escapes.
l Niall Boohan, Tyndall National Institute. www.tyndall.ie
l Margaret Franklin is Vice President of The Institute of Chemistry of Ireland. e-mail: mfranklin@eircom.net
fossil fuels. However, the technical difficulties of extracting it safely, without harming the environment, are considerable. The deposits are at great depth and difficult to access. There is the danger of destabilizing the ocean floor and causing submarine landslides. Finally, there is the risk that the hydrates may break down during the extraction process, with release of methane to the environment. The United States, Canada and Japan all have major research projects underway in an attempt to solve these technical problems, so there is a real chance that methane hydrates could be a source of energy in the future. l Margaret Franklin is Vice President of The Institute of Chemistry of Ireland. e-mail: mfranklin@eircom.net
As the ice cage melts, methane escapes and as here, the gas can be set on fire. Photograph, US Geological Survey. Environmental scientists have raised concerns that rising global temperatures may eventually cause methane to be released from these reservoirs, adding to the greenhouse gases already present in our atmosphere. It is estimated that the amount of methane trapped in methane hydrates could indeed become a significant energy source, possibly on a par with that of all known reserves of
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Methane contained in a cage of water molecules.
SCIENCE WEEK 2014 NOVEMBER 9TH - 16TH Every second around lightning bolts strike the Earth
100
Human THIGH BONES are stronger than
CONCRETE
YELLED
The wingspan of a
If you for more than eight years you would produce just enough sound energy to heat one cup of coffee
Boeing 747
is longer than the Wright brothers’ first flight Wright brothers
48 kph
A hippopotamus may seem huge but it can still run faster than a man
64m
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