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Page 1: Young Scientists Journal 12

Volume 5 Issue 12 Jul-Dec 2012

Online full text at

www.ysjournal.comOnline full text at

www.ysjournal.com

Young Scientists Journal • Volume 5 • Issue 12 • July-D

ecember 2012 • P

ages 49-??

Supported by

Page 2: Young Scientists Journal 12

Have you enjoyed reading Young Scientists Journal?

Read on for some ideas about how to get involved!

www.ysjournal.com

First of all, who are these “Young Scientists”?

They are…YOU!

All our articles are written by – and, perhaps even more unusually, EDITED - by young people aged 12-20. The journal was founded in 2006 by a group of students at The King’s School, Canterbury but now we have authors and editors from high schools all over the world, communicating across the globe by email, Skype,Facebook, etc. The team is managed by the Chief Editor, a student usually in her/his last year at high school.

It is the only peer review science journal for this age group, the perfect journal for aspiring scientists like you to publish research.

What if I’d like to write something for the journal?

Perhaps you’ve done a science project, coursework, holiday placement, competition or presentation in science which made you proud?

It is easy to submit your contribution by uploading it online at www.ysjournal.com and we can accept submissions in a variety of different forms, including pictures, videos and presentations.

We are also keen to receive shorter, review articles, and also other material such as news items, competitions, videos or cartoons for the website.

Can I help to run Young Scientists?

Yes! We love to hear from students aged 12-20 who would like to join our team, editing articles, managing the website, graphic designing, helping with publicity.

You gain unique experience of working on an open-access, peer-reviewed, ISSN-referenced journal while still at school, learning editing and journalism skills which will impress any university.

Send an email to our Chief Editor, Fiona Jenkinson: [email protected]

or find out more by visiting the Young Scientists Facebook page.

And if you are a scientist, science communicator or teacher and would like to know more about how to support the work of the journal, please contact Christina Astin, at [email protected]

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Young Scientists Journal

This magazine web-based Young Scientists Journal is online journal open access journal (www.ysjournal.com). It has been in existence since June 06 and contains articles written by young scientists for young scientists. It is where young scientists get their research and review articles published.

Published byMEDKNOW PUBLICATIONS AND MEDIA PVT. LTD.B5-12, Kanara Business Center, Off Link Road, Ghatkopar (E), Mumbai - 400075, INDIA.Phone: 91-22-6649 1818Web: www.medknow.com

Editorial Board

Chief Editor: Cleodie Swire, UK

Editorial Team Members Emma Copland, UKTeam Leader: Fiona Jenkinson, UK Rachel Wyles, UK

Chris Cundy, UK Arthur Harris, UKLouis Wilson, UK Niyi Adenuga, Nigeria

Louis Sharrock, UK Jake Shepherd-Barron, UKDavid Hewett, UK Harriet Dunn, UK

Fiona Paterson, UK Gilbert Chng, SingaporeMei Yin Wong, Singapore Maria Jose Tamayo, Peru

Alex Lancaster, UK Hannah Morrison, UKMatthew Brady, UK Anne de Vitry d'Avaucourt, FranceBen Lawrence, UK Kiran Thapa, UK

Tim Wood, UK Muna Oli, USARobert Aylward, UK Maddy Parker, UK

Chloe Forsyth, UK Technical TeamSavannah Lordis, UK Team Leader: Jacob Hamblin-Pyke, UKEmily Thompsett, UK Mark Orders, UK

Natalie Cooper-Rayner, UK

Young Advisory Board

Steven Chambers, UK Malcolm Morgan, UKTobias Nørbo, Denmark Arjen Dijksman, France

Lorna Quandt, USA Joanna Buckley, UKJonathan Rogers, UK Lara Compston-Garnett, UK

Otana Jakpor, USA Pamela Barraza Flores, MexicoMuna Oli, USA

International Advisory BoardTeam Leader: Christina Astin, UK

Ghazwan Butrous, UK Anna Grigoryan, USA/ArmeniaThijs Kouwenhoven, China Don Eliseo Lucero-Prisno III, UK

Paul Soderberg, USA Lee Riley, USACorky Valenti, USA Vince Bennett, USAMike Bennett, USA Tony Grady, USA

Ian Yorston, UK Charlie Barclay, UKJoanne Manaster, USA Andreia Alvarez Soares, UK

Alom Shaha, UK Armen Soghoyan, ArmeniaMark Orders, UK Linda Crouch, UK

Anthony Hardwicke, UK John Boswell, USASam Morris, UK Debbie Nsefik, UK

Baroness Susan Greenfield, UK Prof. Clive Coen, UKSir Harry Kroto, UK

Volume 5 | Issue 12 | Jul - Dec 2012

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Volume 5 | Issue 12 | Jul - Dec 2012Young Scientists JournalContents...All rights reserved. No part of this

publication may be reproduced, or transmitted, in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the editor.The Young Scientists Journal and/or its publisher cannot be held responsible for errors or for any consequences arising from the use of the information contained in this journal.The appearance of advertising or product information in the various sections in the journal does not constitute an endorsement or approval by the journal and/or its publisher of the quality or value of the said product or of claims made for it by its manufacturer.The Journal is printed on acid free paper.Web sites:www.ysjournal.comE-mail:[email protected]

Published byMEDKNOW PUBLICATIONS & MEDIA PVT. LTD.B5-12, Kanara Business Center, Off Link Rd, Ghatkopar (E), Mumbai - 400075, INDIA.Phone: 91-22-6649 1818Web: www.medknow.com

EditorialCleodie Swire .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .49

Photography Competition

Young scientists journal photography competition 2012Fiona Jenkinson .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .50

Interview

Interview with Professor Dr. Hamilton Othanel SmithLouis Wilson .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .55

Prize for molecule researchChloé Forsyth .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .57

Review Articles

To what extent can animals aid earthquake prediction?Claire Harnett .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .60

The inefficiency of sewage processing for oestrogen removalNicola King . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .66

The evolution of atomic theoryAllen Zheng .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .74

Should we promote the widespread consumption of biotech foods?Karen Wang .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .77

Evolution of drug resistance in bacteriaJake Shepherd-Barron . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .80

Opinion

The truth behind animal testingShany Sun .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .83

Original Research

Bringing back Betzuca Torrentto life: The bird cages projectEva Crespo, Neus Figols, Anna Junyent, Elena Dibarboure, Katherine Morel, Marta Díaz, Mar Fernández, Marta Sabaté, Sallatyel Carvalho, Albert Soto .. .. .. .. .86

The effect of light intensity on the stomatal density of lavender, Lavandula angustifoliaYoana Petrova .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .89

Addendum 59

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Young Scientists Journal | 2012 | Issue 12 49

Editorial

The Young Scientists Journal is proud to present Issue 12. It features articles on some of the most debated areas of science – genetically modified crops, animal testing, and drug resistance in bacteria – as well as some on topics that you may not know much about, such as proposed methods for lowering the levels of oestrogen in our water supply. I hope that you find this issue informative, interesting, and inspiring. On my last point, we are always looking to receive articles from budding young scientists between the ages of 12 and 20 who would like to see their own work in print.

Following on from the interview with Sir Harold Kroto, published in Issue 11, this issue contains two more interviews with Nobel Prize-winning scientists. The first is with Hamilton Smith, one of the discoverers of restriction enzymes, and the second is with Jean-Marie Pierre Lehn, who was rewarded for his work on the development of cryptates. Allen Zheng’s article on the development of the atomic theory continues the Nobel theme as some of the most famous winners of the Physics prize (Thomson, Bohr, Schrödinger, and Heisenberg) were instrumental to advancements in this field.

An area that has seen progression in recent years thanks to our greater understanding of DNA is biotechnology. Karen Wang’s article probes the idea of genetically modified food, which can present the advantages of being more nutritious, delivering vaccinations, and even disease resistance. The concerns about this technology include those about risk to human health and the possibility of genes spreading, allowing ‘super weeds’ to develop. This phenomenon, in bacteria, is posing one of the biggest challenges to healthcare; our supply of antibiotics for which there are no strains of resistant bacteria is diminishing. The article ‘Evolution of drug resistance in bacteria’ explains how these varieties have increased in prevalence.

The modern pathway in the development of new drugs often involves testing on animals, which has proved to be a controversial practice. Shany Sun explains why she believes that it is worthwhile, as without it challenges such as the antibiotic deficiency, cancer, and acquired immune deficiency syndrome (AIDS) would be overcome at a much slower rate. Another potential avenue for the employment of animals is in earthquake forecasting. Claire Hartnett presents case studies, theories, and quotes from specialists that she procured during her investigations in this well-researched piece.

Our first research article in this issue is a report on fieldwork that a group of Spanish volunteers undertook to help protect their local wildlife. Their tale about an unexpected find shows that investigative science is a possibility for every caliber of scientist. The other paper contains full details about an experiment studying how the density of the stomata on lavender leaves varies under different light intensities.

Finally, this issue is my last as the Chief Editor. Fiona Jenkinson shall fill my role while Chloé Forsyth replaces her as the Head of the Editorial Team. Fiona’s work alongside me over the past year gives me confidence that she will take to the post with aplomb, and I look forward to seeing what they both will bring to the journal. I would like to thank all of the authors, editors, and members of the International Advisory Board (IAB) who have helped make my time working on the journal both rewarding and thoroughly enjoyable.

Cleodie Swire Chief Editor

E-mail: [email protected]: ****

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50 Young Scientists Journal | 2012 | Issue 12

This year, the journal decided to run a photography competition from 1st February to 1st May in order to introduce a new form through which science can be communicated to the journal. We invited students aged 18 and under to take photos using any camera, phone, or other device to compete for prizes according to their age group, related to a scientific theme. These included: The general theme of ‘Energy’ open to all those aged 18 and under, ‘Camouflage’ open to those aged 12 and under, ‘Science behind the Olympics’ for those aged 12–15 years, and ‘The Result of Science’ for those aged between 16 and 18. The photos were submitted via our website along with an abstract to explain the photo.

The panel of judges, whom I would like to thank for giving their time and effort, consisted of: Christina Astin (chair IAB of Young Scientists Journal and Head of Science at the King’s School Canterbury), Ajay Sharman (regional director of STEMNET), Duncan Armour (Science teacher at Simon Langton Boy’s Grammar school and photographer), Ian Wallace (Head of Photography at the King’s School Canterbury), and myself. The photos were both marked and discussed anomalously by the panel of judges according to the following criteria: Image Aesthetics/Artistic qualities, scientific relevance/explanation, Photograph Quality and Concept Originality. It was based on these criteria that the panel decided first place, runner-up, and those highly commended for each theme – although in many cases it was very close.

Young scientists journal photography competition 2012

Photography Competition

Fiona JenkinsonThe King’s School Canterbury, UK. E-mail: [email protected]

DOI: ****

I am glad to announce that we received a total of 53 entries. Although the majority of submissions were from all over England and the USA, there were others from countries including Malaysia, India, Bali, and Latvia. We hope to see this list increase in length next year!

As can be seen from the graph below, the majority of entries were for the ‘Energy’ theme which, as well as being open to any age group, had the highest prize money. The other, age-restricted categories received a lot less entries although standards remained high. The range of ages of entrants is also shown below and perhaps with some of the most successful images coming from younger photographers, we would like to encourage more to enter our 2013 competition.

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It is now with pleasure that we present the winners of each category. Both winners and runners-up received a sum of money in the form of Amazon vouchers.

Prize-Winners

Title: Neon Beams Photographer: Emma DysonTheme: Energy School: St Paul’s Girls School, EnglandAward: Winner Age: 13

Inspired by electricity, Emma wanted to find a way to photograph this form of energy since it is hard to view. Having been captivated by the plasma ball in the science classroom when she was younger, she became interested in the vibrant currents of electricity being transmitted from the electromagnet through the neon gas. Her mother, a science teacher, has one of these plasma balls and this photograph is the result!

Emma explained, “A plasma ball works by the electromagnet in the middle of the glass bulb

sending high voltage currents through the gas (which could be neon or a mixture of other noble gases). These gases, when an alternating current is passed through them, create vivid colours. The reason that it works when a hand is placed on the glass ball is, because a circuit is effectively created through the person, while he or she feels a slight electric shock. However, on smaller voltage bulbs you are unable to feel this shock.”

Title: Hidden Frog Photographer: Jessica BennettTheme: Camouflage School: Forest Lakes Elementary, USAAward: Winner Age: 11

Jessica took this picture of a Cuban tree frog after finding it and remarking at how difficult it was to see, being the same colour as the sediment surrounding it.

She explained how the Cuban tree frog could do this. “[This frog species] can change a variety of colours including shades of green, black, brown and white. They have three different kinds of chromatophores, one that cases brown and black, one iridescent, and one yellow. Although some will have different colours like blue and red depending on whether they are poisonous or not and where they live. To change colour they move either the pigments or the reflective plates in these chromatophores. The colours are not usually based on the background, but they do it because of the amount of light, how they are feeling, and the temperature. Some will even turn white when they are hot and black when they are cold.”

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Title: Mystical Rings Photographer: Abegael TomlinTheme: Science behind the Olympics

School: Homewood school and sixth form centre, England

Award: Winner Age: 15

“The inspiration behind this picture was trying to capture the visual essence of energy as well as linking into the 2012 Olympic Games. I used a slow shutter speed on tripod, which enabled me to photograph the light over a certain amount of time and get it in the right position to show you what it actually is – the Olympic Rings. I used the deep velvety darkness of the background to enhance the brightness of the rings, which have an almost magical quality to them as they appear to be burning brightly like an eternal fire ball giving us a glimpse into the power and golden beauty of an energy that we either take for granted or never have the opportunity to fully appreciate its visual impact. I took this picture in the dark-room at school using an ordinary torch that was used to create this piece showing that sometimes, the ordinary can become extraordinary.”

Title: Fireballs Photographer: Gilda RastegarTheme: The Result of Science School: Lakeside School, USAAward: Winner Age: 16

“This photo demonstrates the physics of how cameras capture light. Like humans who can only see a portion

of the electromagnetic spectrum, cameras can only capture visible light. The quantum theory states that light is emitted from small bundles of particles called photons. In this photo, my camera captured a stream of photons coming from Christmas lights. I set the shutter for a one second exposure so that I could record the path of my camera’s movement. I focused on my subject, and quickly zoomed out. Since my camera moved slightly during the zooming process, the zoomed path is not perfectly linear. Due to the long exposure, all the little Christmas lights look as though they are connected in long strings. The charge coupled device (CCD) sensor in my camera detected the collisions of photons. All of the points of lights hit one point, and since I moved my camera, the points of light made a path, creating a cumulative effect. When I moved my camera, the place the photons first hit was recorded and continued to add on the other registered places. As each photon hit an area on the sensor, there was more cumulative light.

There was no editing done to this photo. When taking this image, I hoped to show what one can do with a source of light and the science behind how a camera captures the image.”

Title: Into The Sun Photographer: Crystal Ng Pei QiTheme: Energy School: SMK Aminuddin Baki

Kuala Lumpur, MalaysiaAward: Runner-Up Age: 16

“Solar energy is energy that is present in sunlight. It has been used for thousands of years in many different ways by people all over the world. As well as its traditional human uses in heating, cooking and drying, it is used today to make electricity where other power supplies are absent, such as in remote places and in space. It is becoming cheaper to make electricity from solar energy and in many situations it is now competitive with energy from coal

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or oil. Since ancient times, the sun has given earth life by emanating light and heat to empower life on earth. This image of the sun’s rays has been given a minimalist theme with very few other elements in the picture to isolate the sheer magnificence of the sun’s rays. Also included within the composition are pylons carrying electrical energy, also a form of energy generated by the sun’s own energy.”

Title: Lizard Hiding on A Rock

Photographer: Jemima Kingdon Jones

Theme: Camouflage School: Hazelwood, EnglandAward: Runner-Up Age: 10

“I was recently on holiday at Bushmans Kloof, a game reserve in South Africa and was on a safari trip looking at wild animals and ancient rock art. I spotted the lizard near one of the rock paintings and took this great picture.

The lizard has a skin colour and texture nearly the same as the rocks so it is very hard to see, if it closed its eye it would be nearly invisible. You can normally only spot lizards when they are moving as most of the time they sit very still. The lizard likes to be on the rocks as it hides it from predators but can get warm from the heat of the rocks. The lizard is cold blooded so needs heat to warm it up.”

Title: Minimizing Drag Photographer: Jackson AlgiersTheme: Science behind the Olympics

School: Mcgill-Toolen Catholic High School, USA

Award: Runner-Up Age: 15

Starting from the age of 5, swimming is Jackson’s favourite sport. He decided to take a picture of a swimmer in the water in the streamline position as the reason swimmers are told to do this is to minimize drag. This is particularly relevant in an Olympic event. Jackson explained “In the picture, the swimmer has pushed off of the wall and is gliding through the water. She is not very efficient. A person looses 91 percent of their energy in the water through drag. The equation, R= ½ DpAv2 is used in order to find the drag or resistance. R is resistance, D is the constant for the viscosity of the fluid, p is the density of the fluid, A is the surface area of the body travelling through the fluid, and v is the velocity of the travelling body. A swimmer can minimize their drag by tightening up and making the shape of a torpedo. They do this by putting one hand over the other with their arms above their head. They squeeze their ears with their biceps and keep their legs straight with their toes pointed. In swimming terminology, this is known as the ‘streamline position.’ It is assumed at the start and after each turn while swimming.”

Title: BLUE 293t Photographer: Elizabeth HamTheme: The Result of Science

School: The King’s School Canterbury, England

Award: Runner-Up Age: 17

“I took this photograph this Easter while interning in a stem cell research lab at The Children’s Hospital Boston. Over the course of the time I was there I grew my own 293t cells to use for artistic purposes. The 293t cells originated as human embryonic kidney cells, and had been transferred by gene mutation to

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cancer cells so they could be propagated in culture quickly by cancer growth. I used a program on the computer called Leica DFC300 FX, which connects the cells under a microscope to the computer where you can take snapshots of them. The cells shown are blue because I used a florescent nucleic dye called DAPI (4′, 6–diamino–2–phenylindole), which stains the nuclei of the cells being photographed blue. For this reason the photograph is made up of the cell’s nuclei only.

I think this photograph represents the result of science because in an abstract way the photograph can represent a section of the planet Earth. The darker region in the bottom right corner is the 96 well plate where the cells grew. In my opinion the shape of this area represents the curvature of the Earth, the cell groupings represent areas of land, and the blank areas are oceans. For this reason the photograph looks like a section of the world itself, and the photograph shows how the results of science are universal.”

Below is a list of those whose photos won, came runner-up and were highly commended:

Category Winner Runner-up Highly commendedEnergy(open to anyone aged 18 and under)

Neon BeamsEmma Dyson

Into The SunCrystal Ng Pei Qi

Birds and a Wind Turbine at Sunset, Michael HofmannHot Air Balloon, Eleanor PowellThe Unique Purple of Chemistry, Gwen LamSun Halo, Kiran ThapaLightning at Night, Stephen SmithLight from a Gherkin, Adam ShortallWater droplet, Kyle MeadowsDancing light, Emilie de BreeFlower power, Lauren Farrow

Camouflage(under 12)

Hidden FrogJessica Bennett

Lizard Hiding on a RockJemima Kingdon Jones

Chameleon Seahorse, Emily PhangThe Preyer, Jonah Linquist

Science behind the Olympics(12–15)

Mystical RingsAbegael Tomlin

Minimizing DragJackson Algiers

The torch, Ryan McDougaldHappy cyclist, Eleanor BennettHanging Mating, Gusti Ngurah Prana Jagannatha

The result of Science(16-18)

FireballsGilda Rastegar

Blue 293tElizabeth Ham

Power Station, Eleanor PowellLight Show, Sarah Cannavino

The other photographs from the competition are shown on the back cover of this magazine and can also be seen on our website. If you think you could be in with a chance to win up to £150, then do not miss next year’s photography competition!

About the Author

Fiona Jenkinson, Editorial Team Leader, is 17 years old and goes to The King's School Canterbury where she is currently studying for her A Levels. She is studying Biology, Chemistry, Physics and Further Maths and has already taken as French. In her free time she enjoys art, music, photography and reading. She wants to study Natural Sciences at University.

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ABSTRACT

Dr. Smith, thank you very much for joining us today. Can I ask you what your interests in science are and what you were awarded a Nobel Prize for?Prof. Dr. Smith: I have had several interests over the years. I started out as a microbial geneticist studying the transformation of bacteria and that work is what led to the Nobel Prize. By chance, I discovered an activity in a bacterium called Haemophilus influenzae [Figure 1], where extracts of the bacteria could cleave foreign DNA without cleaving the cell’s own DNA. In other words, here was an enzyme that could recognise DNA that was from another source – and that fitted the description of “restriction enzyme” that Werner Arber had postulated. So, I went ahead immediately to try to purify that enzyme, and in about 2 years, I had worked it out and published the data.

The interesting phrase you used there was ‘by chance’, which reflects Louis Pasteur’s idea that “chance favours the prepared mind”. Do you think that’s a correct statement?Prof. Dr. Smith: It is a correct statement. In this case,

because I knew about the postulated existence of these enzymes, and we made the chance observation that extracts could cleave foreign DNA, [we] assumed immediately that it was a restriction enzyme.

How old were you when you considered that you had started your scientific career?Prof. Dr. Smith: My father bought me a chemistry set when I was 5 years old, and I enjoyed mixing things, seeing different colours precipitated, burning sulphur etc. From my earliest memory, I think that my interest in both mathematics and science of any sort was almost genetic.

Did you still enjoy doing science as a teenager?Prof. Dr. Smith: Yes, every evening, I worked with my brother – who was also in science – in a basement laboratory that we had. We worked on all sorts of things – electrical things, motors, Tesla coils, radios; we had a fairly sophisticated collection of chemicals, including concentrated acids and so on – we just experimented!

Interview with Professor Dr. Hamilton Othanel Smith

Interview

Louis WilsonSimon Langton Grammar School for Boys, Kent, England, E-mail: [email protected]

Prof. Dr. Hamilton Smith was born in 1931 in New York. He studied at the University of Illinois, eventually transferring to the University of California, where he received a Bachelor of Arts in mathematics. Later, he studied at the Johns Hopkins University, receiving a medical degree in 1956. In 1967, Prof. Dr Smith returned to Johns Hopkins as an assistant professor of microbiology. It was there that in 1969, he made the discovery of Type II restriction enzymes – enzymes that cut DNA at specific points and are now a vital tool in modern genetics. He was subsequently awarded the Nobel Prize along with Prof. Werner Arber and Prof. Daniel Nathans in 1978.

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Did this sort of experience of carrying out experiments without any sort of training affect your scientific career?Prof. Dr. Smith: Yes, I’ve always thought that I was a natural in the laboratory, but it was because of that early experience that I knew about experimentation.

Did you have a role model in science?Prof. Dr. Smith: Well, surprisingly, it was the physicists that were my role models – Einstein is a classic example. It was only later on that I became interested in biological research.

What did you particularly admire about Einstein?Prof. Dr. Smith: The thing that impressed me was the fact that he didn’t benefit much from teachers; he went his own way and didn’t really do well in school. He developed all of his major theories just by thinking and doing thought experiments and using deductive power to build theories. I’ve always been in awe of the theoreticians, even though I’m an experimentalist.

So now you are at the top of your career, what is your advice to young people who are interested in science, especially those who haven’t entered university yet? Prof. Dr. Smith: The most important thing is to follow

what you want to do yourself – don’t let somebody direct you too much. If you enjoy working in a certain area, and maybe have some insights into it that other people don’t have, then pursue that line [Figure 2].

How exactly did you discover the restriction enzyme?Prof. Dr. Smith: The restriction enzyme discovery was a eureka moment – we’d made an observation in the lab that foreign DNA was being degraded by the Haemophilus influenzae organism and it occurred to us that it might possibly be one of the restriction enzymes of the sort postulated by Werner Arber but not yet isolated, so I went home that evening thinking it was probably not true. However, we had a way to assay1 it, so the next morning we set up to assay, and within five minutes, the first point told us we had the thing. It was a fantastic experience to know that you had a new unusual activity, which, although I didn’t know it, would be technologically valuable; it was something new that I could purify and isolate. It wasn’t in my grant, but we just pursued it! I think that was the very pinnacle of my career.

Dr Smith, it’s been a pleasure to talk with you, thank you very much for your time.1An assay is a procedure in molecular biology to evaluate the activity of biochemicals in an organism.

Figure 1: An Image of Haemophilus influenzae (available from http://upload.wikimedia.org/wikipedia/commons/d/dc/Haemophilus_influenzae_01.jpg)

Figure 2: A photograph of Hamilton Smith in 2011 (available from http://upload.wikimedia.org/wikipedia/commons/5/56/Hamilton_Othanel_Smith.png)

About the Author

Louis Wilson was born on 29th October 1994, and is currently studying Biology, Chemistry, Physics, ‘Double’ Mathematics and Russian. In addition to scientific pursuits, Louis enjoys classical music, and plays violin, piano and horn. He hopes to become a geneticist later in life.

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ABSTRACT

Interview with Nobel Prize winner Jean-Marie Pierre Lehn

Jean-Marie Pierre Lehn [Figure 1] is a French chemist who won the Nobel Prize in chemistry in 1987 for his synthesis of cation cryptates.[1] These are cage-like molecules which have an internal cavity that is capable of containing another molecule. He was the innovator in the field of “supramolecular” chemistry which is all about molecular recognition and how molecules selectively bind together.[1] Despite being at the forefront of this field, he looks back to the 1894 analogy of a lock and key to explain how molecules selectively bind to one another because a key has been designed to fit a certain lock in the same way that certain molecules are specifically designed to

bind to one another.

His research also touched on the problems which are linked with molecules binding together. This led to the realisation that specific interactions are needed for recognition between molecules; these interactions are different to those which hold atoms together. Atoms link together through what are known as covalent bonds to make molecules, while molecules bind together by non-covalent interactions.[2] This has led to the discovery of the field of chemistry known as “supramolecular” chemistry, the domain which Lehn has worked in for 30 years which leads to non-covalent bonds being manipulated for inducing recognition processes.

Lehn believes that his science career began in

Prize for molecule research

Interview

Chloé ForsythSir Roger Manwood’s School, Manwood Road, Sandwich, Kent. E-mail: [email protected]

Jean-Marie Pierre Lehn is a French chemist born in 1939 in Rosheim. In 1957 he achieved a baccalaureate in philosophy and experimental sciences before going on to the University of Strasburg to study Physical, Chemical and Natural Sciences. Then, after obtaining his bachelor degree in “Licencié ès sceinces” in 1960, he worked as a junior member of the Centre National de la reserche scientifique at Ourissons lab to work towards his Ph.D. Lehn obtained his degree of Docteur ès Sciences 3 years later and went to Robert Burn Woodward’s lab, Harvard, for a year to work on the total synthesis of B12. In 1966 he became an assistant professor at the Chemistry department of Strasburg University; it was here that Lehn became interested in the nervous system and how chemistry could contribute to him. While trying to find a component which could mimic the actions of natural antibiotics in making membranes permeable to cations, Lehn designed the cation cryptates. This led to the development of “supramolecular chemistry.” In 1970 Lehn became a professor and spent time lecturing at both Strasburg and Harvard. He was awarded the Nobel Prize in Chemistry in 1987 for the development and use of molecules with structure-specific interactions of high selectivity.

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high school. Although, at first, he wanted to study Philosophy at University, in the end, he found that science was more interesting. He began with biochemistry before settling on chemistry as what he wanted to do with his life, because he liked the idea that chemistry had the ability to transform matter. He believes that science and philosophy are closely linked; in fact science is more like philosophy than the latter because in his eyes the idea of philosophy is to acquire wisdom and that is what science does [Figure 1].

When he began his career as a chemist, Lehn never went looking for the celebrity status that he has achieved among his peers, and it has certainly not changed the way he lives his life. As for his own role models, he goes back to his interest in philosophy with the likes of Kant, Nietzsche and Freud. Lehn’s interest in Freud comes from the way he tackled what most people at the time thought of as taboo subjects. This struck a chord with Lehn because he disregards the idea that you can forbid the accumulation of knowledge. To illustrate his point, he uses the example of the creation story in Genesis as he believes that Eve taking the apple from the tree of knowledge was the first act of science as he believes that when trying to acquire knowledge it is important that scientists do not respect the boundaries set down by those in authority.

Lehn believes that science has limitless possibilities and any question can be challenged by science; however, it is also important for scientists to first ask whether or not now is a reasonable time to tackle the question. Lehn takes the example of the question “what is consciousness?” As while he personally believes that it is a consequence of human nature and the way our brain functions, this cannot be proven by science right now.

Lehn has a firm belief that there are no official scientists and this contributes to the comradely nature of science, where, when a scientist publishes any work; other scientists always try to critique and check their findings. To do this they use three criteria: is it observable, is it reproducible and is it explainable?

With his unquenchable desire for knowledge, Lehn finds it incredible when people do not want to understand science and how it shapes our world. He found it even more incredulous when a French Politician from the Green party refused to listen to a

scientific explanation from one of Lehn’s peers. He believes that someone who people are going to vote for should always try to understand the world around them so that they can represent the people of their nation to the best of their abilities.

While Lehn admits that there are some things which are more enjoyable than science in his life – he enjoys playing the piano and would have liked to be a pianist – he enjoys his job so much that if he were reborn he would still be a scientist because he believes that it is the best way to develop the brain in a controlled way. Science is a way of making sense of why we are here – a question that people do not get the chance to answer in everyday life. Science helps people to have a rational approach to life and accept that when you ask a question there are people out there who know better, and we should accept that. Lehn uses the example of having a referendum on genetically modifying organisms; most of the population don’t know anything about the science behind this type of genetics. Instead it would come down to populism, with political parties trying to convince voters what is right when they cannot possibly understand it like scientists do. After all, would you want to hold a vote as to who obtains the position of pilot of an airplane and award the job based on his popularity or would the fact as to whether he knows how to fly the plane be more desirable?

For Lehn the most important thing in life is following your passion, whether it is being a chemist or a

Figure 1: John-Marie Pierre Lehn (Available at: http://en.m.wikipedia.org/wiki/File:Jean-Marie_Lehn.jpg)

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baker, if you have the opportunity to follow your dreams then you should do whatever you can to accomplish them. It is Lehn’s belief that science is a profession and requires a lot of hard work. Take the analogy of a tennis player; you have to train for hours every week to become a professional and it is the same if you are a chemist. You have to work hard to achieve all of the knowledge that you need to become a good scientist. The way to achieve success is hard work as you cannot expect success to fall into your lap with a click of the fingers, this is

the example that Lehn hopes the next generation will take from his career as without the hard work he put in, he would never have achieved his dream, nor won the Nobel Prize!

References

1. Available from: http://superstarsofscience.com/scientist/jean-marie-lehn. [Last cited on 2012 Mar 5].

2. Available from: http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1987/lehn-cv.html. [Last cited on 2012 Mar 5].

About the Author

Chloé Forsyth studies Biology, English, History and Religious studies at Sir Roger Manwood’s School. She hopes to go university to study English and eventually become a journalist.

Addendum to Issue 11

We apologise for any inconvenience that the following mistakes to Issue 11 may have made.

Exploring the quantum world

Lauren Peter’s biography should have read as follows:

‘Lauren Peters is interested in the physics behind our natural world and started studying Physics at university in September 2011’

Household bacteria: Everyday elimination methods uncovered!

1. All DH5μ in the manuscript should be DH5α (alpha instead of mu). 2. In the abstract, e-coli should be E. coli 3. Escherichia coli should be written as E. coli after the first mention. 4. RPM is written as rpm.

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Review Article

To what extent can animals aid earthquake prediction?

ABSTRACT Earthquakes are very hard to predict. Even when Scientists believe an earthquake is likely, it is still hard to comprehend what the probability implies and what precautions should be taken. In this article, it is considered how valuable animal behavior can be for earthquake prediction. Since we cannot accurately predict earthquakes, how do we test the hypothesis that other species can heed warning signs currently unknown to technology?

Claire HarnettInvicta Grammar School, Kent ME14 5DR, England, E-mail: [email protected]

DOI: ***

Introduction

It is reported that around 500,000 detectable earthquakes occur every year, with an estimated 100,000 of those felt by humans without apparatuses and 100 causing damage to the affected area.[1] Though not all of these 100 cause significant damage to human life and economic well-being, in recent years, we have seen many catastrophic events such as in 2011, with the Christchurch earthquake and the Japanese tsunami. This surely raises the question: Why, in such a technologically advanced world, are we still so vulnerable to geological hazards? Is it not time that we were able to accurately forecast these events with enough warning to save human lives? As we are currently unable to successfully forecast earthquakes, there has been an interest in the folklore surrounding earthquakes to hopefully discover whether in this case, literary documentation is able to triumph over science.

Iain Stewart, a geosciences professor at Plymouth University and a well-known television presenter,

suggested in a discussion that unusual animal behavior is “very much the dark side of earthquake science” and that although there is not much information “in the main seismology literature... there are nuggets.” This report aims to find such “nuggets” of information and to explore whether there is biological or geophysical reasoning behind this unusual animal behavior.[2]

The 1975 Haicheng Earthquake

When discussing unusual animal behavior before an earthquake, it is impossible to avoid the 1975 Haicheng earthquake. This event has since been widely branded as the earthquake that was successfully predicted by animals. The earthquake, measuring 7.5 on the Richter scale, struck on February 4; however, thanks to officials evacuating the area several hours before the event, it is thought that hundreds of lives were saved. At the time of the earthquake, the Cultural Revolution was still heavily underway in China, and thus external scientists were not granted entry into the country[3] until months after the event. The Chinese

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people had been ordered to look out for unusual animal behavior, and from this came wide reports of snakes coming out of hibernation and freezing on the earth’s surface.[4]

Although the thought of successful earthquake prediction aroused interest in the Western world, reports since suggest that it was purely political propaganda to encourage support from the Chinese people. Personal communication with Lucile Jones, a USGS seismologist who went to China in 1980 to research the Haicheng earthquake, confirmed this idea:

“It was clear that the signal was politically motivated – the scientists were ordered to ‘learn from the people’ and the peasants were ordered to find animal anomalies and so they found them. The biggest signal in the data was the spike every Saturday afternoon after the Saturday morning commune meeting when the peasants were exhorted to find the anomalies.”[5]

In addition to this criticism, the prediction is frequently criticized by the large number of foreshocks that occurred before the main earthquake, as many geologists argue it was these that alerted officials, rather than the animal behavior.[6]

Reports of Unusual Animal Behavior

Helmut Tributsch is considered the world’s leading scientist when it comes to animals in earthquake prediction, and his book When the Snakes Awake is a list of 78 reports of unusual animal behavior before earthquakes. As the list was compiled in 1982, there have been further numerous reports. Moreover, Chinese scientists have identified 58 species of wild and domestic animals that are thought to have “reliable anomalous reactions before earthquakes.”[7]

A particularly strange report of unusual behavior is that of toad migration preceding an earthquake. Before the Sichuan earthquake of 2008, tens of thousands of toads are reported to have left Mianyang, a city close to the earthquake’s epicenter. [8] Many people reported this behavior; it has since been described as an “earthquake omen.” However, it has since been suggested by local experts that their migration was due to the depleting oxygen source in a nearby river, which would account for the effects on different groups of toads from surrounding villages. [9] Alternatively Andy Michael, a USGS seismologist,

claimed that this was actually an annual toad migration reported to occur the same time every year.[10] Either way, this documentation of unusual animal behavior before an earthquake seemed to be a false alarm.

However, a similar occurrence was seen before the 2009 earthquake in L’Aquila in Italy. Biologist Rachel Grant was completing a 29-day study of toad behavior in Italy around the time the earthquake struck. She documented that 5 days before the earthquake, the number of male toads fell by 96%, and 3 days before the earthquake, the number of breeding pairs unexpectedly dropped to zero.[11] As the documentation was part of a study unrelated to seismology, it is thought to be one of the most reliable documentations of unusual animal behavior in recent years. It has so far remained unexplained, but due to the mass of press surrounding the scientists who were on trial for “manslaughter” for the same earthquake, it has perhaps lacked the deserved media and scientific attention.

Though the majority of the evidence is anecdotal, it seems more than just coincidental that the reports are so widespread in aerial distribution and timescale. A frequent criticism of the documentations of unusual animal behavior comes from the difficulty in establishing a universal definition of “unusual.” Richard Walker, a Royal Society University research fellow from Oxford University, posed the question in an email discussion of “how many times animals behave in a way that we would describe as ’abnormal’ but which isn’t followed by an earthquake, and so is forgotten about.”[12] This idea seems a constant topic of debate within the scientific field.

Unusual Animal Behavior Immediately Before an Earthquake

The most frequently proposed reasoning behind unusual animal behavior before an earthquake is the occurrence of foreshocks, as seen when examining the case study of Haicheng. As there is currently no way to distinguish foreshocks from smaller earthquakes, it is thought that animals react to the shaking of the ground, rather than to any more complicated geophysical precursors.

There is a general consensus within seismological circles that the reason for this is that animals have the ability to detect P (primary) waves before

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humans detect the slower S (secondary) waves. An earthquake causes both S and P waves, but seismic P waves travel approximately 2–4 km/s faster than the S waves that cause the ground to shake,[13] and are therefore detectable by humans without instruments.

The Changes in Electric and Magnetic Fields and Their Effect on Animal Behavior

Before an earthquake, it is thought that electrical pulses in the earth increase the “telluric current.” This is thought to create an electric field, which sparks a magnetic field, thus the effects of them cannot be examined independently. The earth’s electric field naturally varies up to around 10−5 V/m, and before an earthquake, the electric field is thought to fluctuate by around 6 × 10−5. Though this is six times the usual amount, it is approximately the same level of variation that occurs during a normal thunderstorm, and thus cannot reliably be deduced as a geophysical earthquake precursor.

Changes in the magnetic fields on the other hand are thought to have a large impact on animals that use magnetic fields to orientate themselves, such as homing pigeons. In a conversation with former USGS seismologist Jim Berkland, it was mentioned that “homing pigeons were being lost” during stronger Californian earthquakes.[14] It seems that migrating birds show deviations from their usual course due to local geomagnetic anomalies. In a lecture given by Friedemann Freund, he showed a disruption of the circadian rhythm of rats that occurred at the same time as a spike in the magnetic field before the 2008 Sichuan earthquake.[15] Though both of these examples seem to suggest an animal reaction to geomagnetic anomalies, they are still only considered as “anecdotal,” so do not pertain to be reliable enough. The opposing argument is presented by Tong, who claims, “the variations due to normal (non-seismic) factors are only 30 gammas; those due to earthquakes are usually only 20 gammas.”[7] This therefore suggests that an animal would not be able to distinguish between a change in the magnetic field caused by impending seismic activity and a normal magnetic field variation.

Scientific Viability through the Theory of Increased Ionization

The possible precursors presented so far seem to be dubious in their reliability when examined in direct relation to the stimulation of unusual animal behavior. This theory has, for a long time, seemed inexplicable. However, a paper written in 2011 that mainly focused on ground water chemistry changes before major earthquakes may offer us a solution.[16] Grant et al.propose a theory of increased ionization, an idea that was also mentioned in Tributsch’s When the Snakes Awake but at that time required more research to be considered a serious possibility. This research has since been done, and Grant et al. appear to put forward a convincing argument.

When rocks are put under pressure, it is thought that an electric current is generated within the rock. The theory stems from the principles of the piezoelectric effect and has been furthered by Grant et al.[16] who put forward the idea that a reaction occurs between the silicon bonds of the rock and oxygen and forms what is called a “positive hole” in the rock. This hole can then move away from the initial site of strain, spreading the stress into the unstressed rock. This means that the original stressed rock becomes negatively charged as it has lost the charge to the originally unstressed rock, which gains a positive charge. This effectively turns the rock into a battery by creating a flow of electric potential. Not only does the electric charge create an electric current beneath the earth’s surface, but if it is strong enough (i.e., in more major earthquakes), it is thought that it can also generate microscopic electric fields that are able to ionize the air surrounding the rock.

Positive ions in the air are also thought to cause serotonin levels to increase, both in humans and animals, and thus would give reason to unusual animal behavior.[16] It is thought that an increase in serotonin levels in animals leads to irritable behavior, and also has the ability to cause physiological deterioration[17] which may explain the unusual animal behavior before earthquakes.

Though the idea of increased ionization seems the most likely as of yet, discussions with Alexander Densmore, the Deputy Director of the Institute of Hazard, Risk and Resil ience at Durham University, suggested, “just because something is possible, doesn’t mean that it is definite” (personal correspondence, 2012).[18] There are still flaws in this line of thinking, for example, the argument that the electrical conductivity of the ground means that the electric field would not be suggested at the

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magnitude required to ionize the air. Though this theory is without doubt the most promising, Iain Stewart’s claim that this is “dark side of earthquake science” still rings true.

Critical Response from Academics

The theory of animals in earthquake science is frequently criticized by the variability in the animal’s responses from reactions of agitation to panic to excitement. Cynics often argue that if one dog reacts unusually before an earthquake, surely all dogs should react the same way before all earthquakes. [10] However, this line of reasoning seems to have a fairly simple answer in that there is huge variability within a species. In addition to this, Tributsch’s list of 78 incidences of unusual animal behavior preceding an earthquake[19] includes around 85 different species,[20] which makes it unsurprising that one particular geophysical signal could be responsible for the reactions of so many different species. In addition to this, we have to take account of the variability within a species, which may lead to varying responses even to the same geophysical signal. In discussions with John Rollins, a professor from the University of Southern California, it was also made evident that the geophysical variability between earthquakes could easily be responsible for the variability in animals’ responses. He put forward the idea that “different faults have different failure strengths,” so their ability to surpass an animal’s stress threshold would be different for each earthquake that occurs. [21] This reasoning also shows how difficult coherent research would be into this field, as there are so many independent variables.

Another criticism of the usefulness of animals in earthquake forecasting often lies with the flaws in the people involved in the data collection. For example, the data are often collected after the event, which has led some critics to argue a theory of “confirmation bias.”[10] This means that an owner of a domestic animal will notice unusual behavior, but only link it to the earthquake after they have felt the shaking or heard news reports of the earthquake, and thus the information is unreliable. Such an idea was supported by Dr. Max Wyss, the Director of the World Agency of Planetary Monitoring and Earthquake Risk Reduction, who claims, “human beings have a tendency to believe anything that catches their fancy.”[22]

Primary research was conducted as part of this report, whereby an interview with 42 academics

from the fields of geology and seismology was conducted; in the majority of whom are experts in the fields of seismology. Table 1 shows just some of the responses in these interviews:

Figures 1 and 2 show the extent to which the idea of animals in earthquake prediction is ridiculed within academic circles. An almost unsurprisingly high percentage of the academics asked believe that animals present absolutely no chance of improvement in earthquake prediction. The email sent to the academics asked only for two yes/no answers; however, a large majority of the people responded with more comprehensive answers. Of the 31 more detailed replies, 58% blamed their cynicism on the “anecdotal” nature of the current evidence, making it unreliable. Conversations with Friedemann Freund, a senior NASA researcher, introduced an opposing viewpoint:

“Many mainstream seismologists use the word ‘anecdotal’ to call into question something which THEY don’t understand. They conveniently forget that every discovery in the natural sciences begins with ‘anecdotal’ observations. Just think of shooting stars. In the past people had to wait endless hours through the nights to see them. Once it was understood that they are debris particles in comet trails, which the Earth intersects at certain times of the year, the chances of seeing them and even seeing fireballs became much better... it all boils down to understanding.”[25]

Freund presents an interesting idea that is mirrored by Tributsch (p. 11), that “few seismologists had the courage to take the evidence seriously.”[20] This therefore presents the idea that the problems lie with the current world of science. Tributsch even goes so far as to suggest that the cynicism of the science world may have dissuaded many people from passing on their experiences of earthquake

Table 1: Descriptions used to directly describe the use of animals in earthquake predictionDescription Source“Magical thinking at its worst” Email correspondence with Lucile

Jones, 2012[5]

“Just voodoo” Email correspondence with Thorne Lay, 2012[23]

“Something of a distraction... a complete diversion from finding (a method of earthquake prediction)”

Email correspondence with Richard Phillips, 2012[24]

Part of “the pseudo-science realm” Email correspondence with Iain Stewart, 2012[2]

“Nonsense” Email correspondence with Max Wyss, 2012[22]

“Unscientific folklore” Tong, 1988[7]

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precursors, for fear of being ridiculed, a fear which is shown in Table 1 to have fair foundations.

Tributsch (p. 213) argues, “scientific progress seems able to offer us everything except the knowledge that takes centuries to acquire,”[19] which brings into question the future of the idea of animals in earthquake science. It is necessary for us to establish whether the cynicism comes from fear of researching something currently considered as “nonsense,” or whether the cynicism really is because the idea is just not scientifically plausible.

The Future of the Use of Animal Behavior in Earthquake Prediction

Susan Hough, another well-known author in earthquake science, claims, “earthquake prediction represents an ongoing collision between science and society.”[6] It seems almost that this collision is taking over from the importance of the research itself.

Hough does, however, pose the question of whether the small-scale approach of villages can in this case triumph over the advances of science. Tributsch[19] was really the first to make a serious impact in the field of animals in earthquake science, and after his demands for additional research, there seemed to be a boom in interest in the late 70s/early 80s. Fattahi, a geophysics lecturer from Oxford university, claims, “after the failure of all people who work on earthquake prediction, the available funding has declined a lot” (personal correspondence, 2012).[26]

The current available research makes it clear that more investigation is needed into the various different geological precursors, and particularly into the area of increased ionization. Kirschvink suggested, “it is clearly prohibitively expensive to record continuously a random variety of physical and chemical parameters near all possible earthquake epicenters”[13] (p. 314). This is an understandable argument as constant monitoring would be required; however, Kirschvink also suggests that the introduction of inexpensive monitors could severely impact our current knowledge. Constant monitoring does propose huge benefits as it would not only pick up unusual activity before an earthquake, but could also provide a baseline for “usual” activity. A constant record would also oppose the argument that we do not get reports of unusual behavior without an earthquake.

There is certainly controversy surrounding the concept of using animals in the forecasting of earthquakes. Though no conclusive research has yet been published, one could argue that there must at least be a possibility for truth in the “folklore,” else the idea would immediately be dismissed on a large scale. An idea further to those discussed in this report is that even if animals do not respond with enough notice to directly impact or enable earthquake prediction, they may at least point us to geophysical precursors that may otherwise have gone unnoticed.

It should be noted that the aforementioned research “boom” in the late 70s was even supported by the USGS, who according to Tong funded two research projects into “Abnormal Animal Behaviour Prior to Earthquakes.”[7] This suggests that the idea is not as ridiculous as many geologists and seismologists have implied, as it was once seriously considered by the USA’s leading seismological body. Our advances in technology have perhaps made people less open to traditional scientific methods. Tributsch’s view from over 30 years ago still rings true in that more

Figure 1: Answers to the question `Do you think examining animal behaviour has the potential to seriously impact earthquake prediction?'

Figure 2: A graph to show the percentage of academics asked who mentioned the idea of `anecdotal evidence' in their responses

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research is the only way to confirm or rule out the idea of using unusual animal behavior as a reliable method of earthquake prediction. Freund ended his research paper from 2003 with the quotation from philosopher Arthur Schopenhauer:

“All truth passes through three stages. First, it is ridiculed. Second, it is violent[ly] opposed. Third, it is accepted as being self-evident.”[27] (p. 67)

Based on this, one could say that the prospect of animals in earthquake science has already succumbed to ridicule and violent opposition. If Schopenhauer is to be true, the only stage left is self-evidence.

References

1. Mott M. Can Animals Sense Earthquakes? National Geographic News.2003 November 11.[Internet]. Available from: http://news.nationalgeographic.com/news/2003/11/1111_031111_earthquakeanimals.html. [Last accessed on 2012 Jan 9].

2. Stewart I. [email] Message to C. Harnett, sent 2012 January 27, 09:37.

3. Kanamori H. Earthquake prediction: An overview. IntHandb Earthquake EngSeismol 2003;81B:1205-16.

4. Bhargava N, Katiyar VK, Sharma ML, Pradhan P. Earthquake prediction through animal behaviour: A review. Indian J Biomech 2009;Special Issue:159-65.

5. Jones L. Earthquake Prediction.[email] Message to C. Harnett, sent 2012 January 28, 23:35.

6. Hough S. The road to haicheng. In: Predicting the unpredictable: The tumultuous science of earthquake prediction.Princeton: Princeton University Press; 2009. p. 58-85.

7. Tong WK. Abnormal behaviour and the prediction of earthquakes.Ph. D. Northeastern Illinois University; 1988.

8. Hongyi W. Public asked to report earthquake omens. China Daily 2011 May 30. [Internet]. Available from: http://www.chinadaily.com.cn/china/2011-03/30/content_12247121.htm. [Last accessed on 2012 Jan 3].

9. Jee Y. Toad migration in Jiangsu, China. YeinJee’s Asian Journal2008 May 19.[blog]. Available from: http://yeinjee.com/2008/toad-migration-in-jiangsu-china/. [Last accessed on

2011 Dec 30].10. Michael A. Skeptic check: Dubiology. Interviewed by. Seth

Shostack [radio] SETI Big Picture Science. 2011 November 28.11. Walker M. Toads can ‘predict earthquakes’ and seismic

activity. BBC Earth News 2010 March 31. [Internet]. Available from: http://news.bbc.co.uk/earth/hi/earth_news/newsid_8593000/8593396.stm. [Last accessed on 2012 Jan 3].

12. Walker R, [email protected]. Earthquake Prediction. [email] Message to C. Harnett, sent 2012 January 27, 11:27.

13. Kirschvink JL. Earthquake prediction by animals: Evolution and sensory perception. Bull SeismologSoc Am 2000;90:312-23.

14. Berkland J, [email protected]. Earthquake Prediction.[email] Message to C. Harnett, sent 2012 January 28, 06:32.

15. setiinstitute. Living with a Star, Dangerously – Friedemann Freund2011.[video online]. Available from: http://www.youtube.com/watch?v=Ndj85uAHrPg. [Last accessed on 2012 Jan 27].

16. Grant R, Halliday T, Balderer WP, Leuenberger F, Newcomer M, Cyr G, et al. Ground water chemistry changes before major earthquakes and possible effects on animals. Int J Environ Res Public Health 2011;8:1936-56.

17. Buskirk RE, Frohlich C, Latham GV. Unusual animal behaviour before earthquakes: A review of possible sensory mechanisms. Rev Geophys Space Phys1981;19:247-70.

18. Densmore A. Earthquake Prediction.[email] Message to C. Harnett, sent 2012 January 27, 12:22.

19. Tributsch H. When the snakes awake: Animals and earthquake prediction. In: Langner P, editor. Cambridge, Massachusetts: The Massachusetts Institute of Technology; 1982.

20. Tributsch H. Bionics of natural disaster anticipation. J Bionic Eng 2005;2:123-44.

21. Rollins J. Earthquake Prediction.[email] Message to C. Harnett, 2012 January 27, 21:16.

22. Wyss M. Earthquake Prediction.[email] Message to C. Harnett, sent 2012 February 7, 18:28.

23. Lay T. Earthquake Prediction. [email] Message to C. Harnett, sent 2012 January 27, 18:35.

24. Phillips R. Earthquake Prediction.[email] Message to C. Harnett, sent 2012 January 27, 10:31.

25. Freund F. Earthquake Prediction. [email] Message to C. Harnett, sent 2012 January 27, 16:32.

26. Fattahi M. Earthquake Prediction. [email] Message to C. Harnett, 2012 January 30, 8:41.

27. Freund F. Rocks that crackle and sparkle and glow: Strange pre-earthquake phenomena. Journal of Scientific Exploration 2003;17:37-71.

About the Author

Claire Harnett, 17 is a student at Invicta Grammar School, currently studying Further Maths, Geography, German and English Literature. She enjoys travelling and going to the theatre. Her interest in earthquakes has really flourished in the last year and Claire plans to study BSc in Geological Hazards next year at Portsmouth University.

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ABSTRACT

Source of the Problem

Currently, many of the water sewerage systems in the UK are not advanced enough to cope with the input of oestrogen into the water supply. Every day, millions of women around the world wake up and take their contraceptive tablet [Figure 1], the pill, thinking nothing more of it than as if they were simply taking any other pharmaceutical medication. However, the 17α–ethinylestradiol (oestrogen) within this tablet does not remain in the body. As the woman urinates, the drug leaves the body and enters the water system. Most of the sewerage systems around the world were built before the contraceptive pill was even invented; the thought of filtering out thousands of pharmaceuticals such as oestrogen was never a deliberation. In the society today, no fewer than 100 million women worldwide are taking the Pill and 3.5 million of those are from the UK.[1] The effect of the introduction of this hormone into the water system has only until very recently been flagged up as a problem.

Examples of the Problems Caused by the Lack of Efficient Filtering of Oestrogen

The problems caused are multifaceted; they include the following:

The feminization of the male roach fishVitellogenin is an oestrogen-responsive egg yolk precursor protein which is present in all female fish including the roach fish. In 1994, caged male roach fish were discovered to have excessive amounts of vitellogenin, suggesting that these fish had been exposed to high levels of forms of oestrogen; an extreme case is shown in Figure 2. Originally, this finding was put down to the existence of industrially created oestrogen replacements – for example, nonylphenol, a “breakdown product” of a variety of widely utilized non-ionic surfactants. However, it has been discovered that the natural 17α–ethinylestradiol (the oestrogen found in the Pill) as well as the natural steroids 17α-estradiol and estrone are more responsible than nonylphenol for

The inefficiency of sewage processing for oestrogen removal

Review Article

Nicola KingThe King's School, Canterbury, UK. E-mail: [email protected]

DOI: ???

One hundred million women worldwide take the contraceptive pill. The UK’s water systems do not have the capability to filter out the oestrogen introduced through the consumption of the pill. This causes problems such as the feminization of the roach fish, cancer, and infertility. Possible solutions include: incorporating biofilm into the sewage treatment process, which increases the biodegradation activity level of the microorganisms employed in the process; reverse osmosis, which filters the oestrogen out under pressure; ozonation, which uses ozone to decompose the oestrogen; and replacing the pill with the alternative contraceptive the mini-pill, which contains no oestrogen.

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contributing to this effect. Overall, studies have shown that it is the 17α-ethinylestradiol that is causing most of the problems.[2]

CancersThere are vast benefits to humans in filtering out the oestrogen in the water supply. It is well known that oestrogen is a major cause of cancers,[3] including breast, endometrial, cervical, colon, brain tumors, testicular, and prostate cancer. Elevated levels of the hormone can also cause an increase in infertility.

Cancer affects one in three people at some time in their lives, though some tumors are much less common than others. In the UK, the commonest form in women is breast cancer, followed by colorectal, lung, and skin cancer. The Office of Health Economics has calculated that the cost to the National Healthcare Service (NHS) of treating cancer in 1998/99 was £1986 million, of which £15754 million represented hospital treatment costs, £177 million was spent on anti-cancer medicines, and £54 million was accounted for by GP and pharmacy costs.[4] I must clarify that although oestrogen is a major cause in many types of cancer, not all cancers are related to this hormone.

Current Ineffective Sewerage Treatment Process

Generally, the chief process of sewerage treatment is activated sludge. Activated sludge is a process [Figure 3] in sewage treatment in which air or oxygen is forced into sewage liquor to develop a biological floc (precipitate that appears during flocculation), which

Figure 2: Testis of intersex roach showing presence of ova within the testicular tissue (tests have been done in labs which prove that oestrogen has this affect on the tissue) [Available from http://www.eng.ox.ac.uk/chemeng/pdf/oestrogens.pdf]

Figure 3: The current system of activated sludge plants [Available from http://www.oakharborcleanwater.org/proposed-future-treatment-facility-technologies]

Figure 1: Woman taking the pill [Available from http://topnews.net.nz/content/214776-hormonal-pill-tends-alter-sexual-desire-women-says-research]

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reduces the organic content of the sewage. Once the sewage has received sufficient treatment, excess mixed liquid is discharged into settling tanks and the supernatant is run off to undergo further treatment before discharge. Part of the settled material, the sludge, is returned to the start of the aeration system to re-seed the new sewage entering the tank. The remaining sludge then undergoes further treatment.

Currently, activated sludge plants remove about:• 70–88% of 17β-estradiol• 50–75% of estrone• 50–85% of 17α-ethinylestradiol

This appears effective but leaves about 1–10 ng/dm3 (parts per trillion) of these harmful hormones in the water system, which, despite the small concentrations, can still have a devastating impact on the environment as stated earlier.[5]

The UK’s Disadvantage

The United Kingdom has a particular disadvantage in that it has very small rivers [Figure 4] to source the supply of water in addition to the fact that it serves a high population density. As a result, the UK’s Environment Agency is thinking of ways to control the output of these hormones into the water supply. It has been brought to light that in London, water has passed through eight people prior to its ingestion by any individual.[6]

What Properties Should the Solutions Have and Why?

Many of these harmful estrogens possess hydrophobic characteristics, so they are insoluble.

The hydrophobic effect is fundamentally based on the tendency of (polar) water molecules to exclude non-polar molecules, which leads to segregation of water and non-polar molecules.[7]

In addition to the previously mentioned chemicals, which are endocrine disrupters, examples such as 17β-estradiol only slowly biodegrade – at the very least, it is necessary to modify the activated sludge plant to eliminate them at a reasonable rate.

Impractical Solutions to Improving the Ineffective, Current Activated Sludge Plants

• To double, triple, or even quadruple the quantities of activated sludge bacteria existing inside the last tank, where the biodegradation activity must be increased to break down more oestrogen. The last tank in many sewage works is not easily accessible and it is, therefore, difficult to place the bacteria sediment in this tank.

• Making the aeration tank much bigger will result in the tank holding water for longer, which will allow more time for the biodegrading process to take place. Again, there is a negative side to this in that the necessary large size of the treatment plant results in an increase in expenses. Furthermore, this expansion and modification can only happen in plants that have onsite space to allow for it.

As these treatments are very costly, other more practical solutions are more commonly being incorporated into sewerage systems.

Chosen Solutions

BiofilmA biofilm is a complex aggregation of microorganisms growing on a solid substrate. Biofilms are characterized by structural heterogeneity, bacterial genetic diversity, complex community interactions, and an extracellular matrix of polymeric substances.[8] The proportion of an organic contaminant such as oestrogen that can be removed from the sewage effluent depends on the attractive power of the biofilm sorbent and the quantity of sorbent present per unit of volume.[9]

As the capability to enlarge the biological sorbent’s “attractiveness” is restricted by space, it can be overcome by raising the quantity of sorbent. Activated

Figure 4: Image of Barlings Eau River [Available from http://www.geograph.org.uk/photo/186939]

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sludge tanks work with a biomass content ranging from 2.5 to 4 g/dm3, as an increased concentration may create a settling problem. A biofilm, when joined onto carrier substances, does not create the same difficulties in eliminating sludge out of the effluent as a standard biofilm. A biomass of 12–35 g/dm3 could possibly be upheld inside a separate section of the activated sludge tank using a biofilm; this is a 3–8.5 fold increase in biomass. and therefore an increase in biodegradation activity level.

Figure 5 shows how a biofilm actually lets organisms grow on it, as described in the previous paragraph. This can provide a more sorbent binding surface as well as an increased biodegradation capacity than is usually present. The ratio of high biomass and high available surface area offers the highest capability to absorb and remove the oestrogen compounds from the aqueous phase.

The process of eradication of the oestrogen contaminants is in two stages: primary adhering to the bacterial surfaces and biodegradation on the bacterial surfaces.

To demonstrate how biofilms are supported and cultivated under normal sludge plant conditions, scientists, including Andrew Johnson, carried out various studies. They obtained and positioned a large selection of different media inside cages made from stainless steel, and immersed them into the aeration tank of a standard activated sludge plant. The media were removed from the tank for analysis after some time for investigation in the lab.

The biofilm was used to start bacterial growth in a “bench-scale unit” [Figure 6]. For safety reasons, they used Ultra-High-Temperature (UHT) skimmed milk (with added nitrogen and phosphorus) instead of sewage as this has the same biomass range as regular sludge plant sewage. This fluid was then contaminated with oestrogen. The medium with biofilm fastened to it was placed in an “up flow glass bioreactor” [as seen in Figure 6]. The following passage is from the scientist who led the studies: “The feed liquor moved through the bio filter, was aerated and then overflowed to the next reactor. The typical hydraulic residence time in the bioreactors was around 20 minutes. Both the feed and effluent were constantly monitored for oestrogen using Liquid Chromatography Mass Spectroscopy.”[9]

To prove that the biofilm could efficiently remove

Figure 5: Showing how biofilm allows organism growth [Available from http://www.teamaquafix.com/h2s.aspx]

Figure 6: Showing how the experiment was carried out [Available from http://www.eng.ox.ac.uk/chemeng/pdf/oestrogens.pdf]

oestrogen, 100 μg/dm3 ethinylestradiol (EE2), the first orally active semi-synthetic steroidal oestrogen, was inserted into and remained in the bioreactor for 20 days. During the test, 90–95% of the EE2 was removed [Figure 7].

How appropriate is this solution?• This method is appropriate as it removes

almost all of the oestrogen in the effluent. It is

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a relatively low-cost solution compared to other more expensive approaches, as it only requires adding moderately cheap mechanisms into existing activated sludge plants. Other solutions involve building whole new plants or machinery that would be inappropriate, both in terms of cost and the environment.

• Although this solution appears to be economically superior to the other solutions, it does still involve a setup cost in correctly inserting the biofilm. There is also a time when the plant is not operative (during repairing and replacing biofilm) and one must consider where the sewage will be held during this period. Some options include: holding it in tanks, which is expensive; releasing the load into the sea and rivers, which is polluting; or sending it to other functioning plants, putting a strain on their work.

• Another flaw with this solution is that there is restricted growth of bacteria on the biofilm, and therefore with time, the ability to hold and biodegrade the oestrogen may be affected. Therefore, the biofilm may need replacement and this is inconvenient as constant inspection and repairing is required, and again, there is the problem of storing the sludge during the process.

• The risk of the method to other organisms is that the biofilm may begin to let harmful or polluting bacteria cultivate there, as there are optimum bacterial conditions. These have the threat of contaminating the effluent at a later stage, which may cause more harm than good to the

organisms that use the water.• The obvious benefit of the methodology is

removing at least 80% more oestrogen from the effluent, and consequently, the environment and the population would not be exposed to the high oestrogen levels, and are therefore less likely to be prone to the negative side effects that were previously discussed.

• There is an environmental benefit to this solution in that the Earth’s resources are not required in this method. It can be seen in Figure 8 that the aeration tank involved is easily accessible, so there would be no need to make a contraption to get inside it, again saving resources and conserving time.

Figure 7: A table showing EE2 escape following 2 h of treatment with biofilm sustained by synthetic sewage [Available from http://www.eng.ox.ac.uk/chemeng/pdf/oestrogens.pdf]

Figure 8: Aeration tank of an activated sludge plant [Available from http://www.alcosan.org/Education/HowitWorks/HowItWorks2/tabid/95/Default.aspx]

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• An additional environmental benefit is that aqueous plants and underwater habitats will be much less polluted by oestrogen.

• The only input of greenhouse gases into the atmosphere is in the transport of the materials to each of the sludge plants, when CO2 will be released.

Reverse osmosis“Reverse osmosis,” as the name suggests, involves the opposite action to osmosis and is shown in Figure 9. Osmosis is the movement of a solvent through a selectively permeable membrane into a s olution of higher solute concentration that tends to equalize the concentrations of solute on the two sides of the membrane.

In reverse osmosis, the membrane is used as a very fine filter to produce pure water from water contaminated with the oestrogen. The polluted water is kept on one side of the membrane and then pressure is applied to stop, and then reverse, the osmotic process.[10]

• There are many advantages to reverse osmosis. It is environmentally friendly because the process does not create or use harmful chemicals. Moreover, the process does not require many raw materials and in this respect, it is considered to be “green.” It is also very effective in oestrogen removal.

• However, a major disadvantage in the process

is that reverse osmosis requires a vast quantity of water as well as pressure. Such systems typically return as little as 5–15% of the water pushed through the system;[10] this means that the process is very time consuming, and the method very inefficient. This enormous volume of water also has to be free of bacteria; to create a system to carry out all this would require time and money. The outcome of removing oestrogen is beneficial though, so there is a decision to be made as to whether the amount of money required to be spent on this system is worth the benefit of the oestrogen removal.

OzonationOzone (O3) is an “unstable gas” containing three oxygen atoms; the gas will easily convert back to oxygen, and during this conversion a free oxygen atom or “radical” is created. The free oxygen radical is extremely reactive but has a short half-life. In normal circumstances, it can only last for milliseconds, and in this time, it will oxidize practically any chemical, including oestrogen. It has seven times the oxidizing capability of free chlorine atoms, but does not create toxic waste (which the majority of other chemicals do).

Role of ozone in water treatmentAs ozonation has the ability to break up virtually any chemical, oestrogen in the water is also broken up. As ozone degrades back to oxygen and free radicals,

Figure 9: Image of reverse osmosis process [Available from http://bmet.wikia.com/wiki/Reverse_Osmosis_Unit]

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the probability of water oxidizing other chemicals is raised. This capability to oxidize is determined as “redox” potential – the higher this potential, the greater the intensity of the free radicals. As the redox potential is increased, so is the range of chemical species that can be oxidized.

The advantages of ozonation are as follows• Removes oestrogen• Reduces oxygen demanding matter, turbidity

and surfactants • Removes most colours, phenolics and cyanides • Increases dissolved oxygen • No significant toxic products• Increases suspended solids’ reduction[11]

The disadvantages of ozonation are as follows• High capital cost • High electricity consumption • Highly corrosive, especially with steel or iron and

even oxidizes Neoprene[11]

The mini-pillThe mini-pill is another form of oral contraception that contains no oestrogen, as stated by the GP Dr. David Delvin: “Unlike the ordinary pill it contains just one hormone – not two. That hormone is a progestogen. A progestogen – which is an artificially manufactured hormone – is very like progesterone, which is one of the female hormones the body produces. Unlike the ‘ordinary’ pill, the mini-pill contains no oestrogen at all.”[12]

It may be suggested that the population increase their use of this form of oral contraception rather than using the regular oestrogen pill, which is currently the most popular form of contraception.

The latest progestogen only pill (POP) “Cerazette,” also known as “desogestrel,” is considered as effective as the oestrogen contraceptive pill (OCP; i.e. combined pill) in protecting against pregnancy [Figure 10].

Advantages• The first and obvious advantage is that there

will be a considerable reduction in the country’s oestrogen levels.Therefore, all the problems that these high levels of oestrogen create will either be terminated or significantly reduced.

• It protects the population from unwanted pregnancy.

• It has the following advantages in its primary

function as a contraceptive:1. Effective and reversible (failure rate 0.5% in

original POPs but 0.17% with Cerazette) 2. Decreased risk of venous embolism 3. Decreased risk of endometrial cancer,

pelvic inflammatory disease, premenstrual syndrome, mastalgia and thrush.

4. Does not interfere with breast-feeding. 5. Not affected by antibiotics, sodium valproate

or clonazepam. 6. Causes fewer metabolic changes – does not

raise blood pressure or increase cholesterol levels. Minimal effects on clotting mechanism and glucose metabolism.[13]

Disadvantages• There is insufficient evidence to support the idea

that the drug does not cause the same effects as oestrogen in effluent.

• It would be incredibly difficult to persuade a nation to switch to another form of contraception, if they are happy with their current choice, in a short time.

• The following are the disadvantages to its primary function as a contraceptive:1. Needs to be taken daily.If using any POP

other than Cerazette, it must be taken at the same time every day or within 3 hours.

2. Irregular periods, heavy periods or no periods, can occur.

3. Interactions with enzyme inducing drugs can occur (rifampicin and some anti-epileptics).

4. May worsen acne. Side effects – headaches, dizziness, nausea, bloating, breast tenderness, moodiness and loss of libido.

5. Ovarian cysts may occasionally develop.[13]

Figure 10: The Cerazette mini-pill [Available from http://www.2womenshealth.com/Cerazette.htm]

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Conclusion

Having evaluated the various solutions to the problems that oestrogen in the effluent creates, I conclude that biofilm in the aeration tanks of activated sludge plants is probably the best option, having considered the advantages and disadvantages of all the various solutions. The main advantages it has over the other solutions I have studied are as follows:• Biofilm is a more cost-effective solution compared

with ozonation and reverse osmosis.• Biofilm is a comparatively easy method to remove

oestrogen from the effluent. • Once the biofilm has been installed in activated

sludge plants, there is no requirement for annual replacement of materials, and aeration tanks allow for easy access.

• Biofilm does not rely on unpredictable public cooperation, whereas using the mini-Pill solution does.

• Biofilm is the most environmentally friendly solution.

• Biofilm is the most effective long-term solution for removing oestrogen from the water.

References

1. Stacey D. Top 10 Pill Myths. About.com, 2007. Available from: http://contraception.about.com/od/contraceptionmyths/tp/pillmyths.htm.[Last accessed 2011 Feb].

2. Delvin D. Contraception – The Contraceptive Pill. Net

Doctor, 2011. Available from: http://www.netdoctor.co.uk/sex_relationships/facts/contraceptivepills.htm.[Last accessed 2011 Feb].

3. Oestrogen – The Killer in Our Midst. Cancer Active, 2003. Available from: http://www.canceractive.com/cancer-active-page-link.aspx?n=661.[Last accessed 2011 Feb].

4. Bartlett S. A-Z of Medicines Research. 4th ed. United Kingdom: The Association of the British Pharmaceutical Industry; 2007.[Last accessed 2011 Feb].

5. What is Activated Sludge? Bionewsonline.com, 2005. Available from: http://www.bionewsonline.com/x/what_is_activated_sludge.htm.[Last accessed 2011 Feb].

6. 10 Facts About Water in London. Watercoolersdirect.com, 2008. Available from: http://www.watercoolersdirect.com/resources/10-facts-about-water-in-london.html.[Last accessed 2011 Feb].

7. Hydrophobic Effect. Wikipedia.org. Available from: http://en.wikipedia.org/wiki/Hydrophobic_effect.[Last accessed 2011 Feb].

8. Bioscreen C. What is Biofilm? Bionewsonline.com, 2005.Available from: http://www.bionewsonline.com/n/what_is_biofilm.htm.[Last accessed 2011 Feb].

9. Johnson A,Darton R. Removing Oestrogenic Compounds from Sewage Effluent.Available from: http://www.eng.ox.ac.uk/chemeng/pdf/oestrogens.pdf.[Last accessed 2011 Feb].

10. Water Ozone Generator/Ozonator. Air Purifier’s Superstore. Available from: http://www.air-purifiers-superstore.com/air_water_ozonator.html.[Last accessed 2011 Feb].

11. Rossa-Lee C.Ozonation of Wastewaters. Mountain Empire Community College. Available from: http://water.me.vccs.edu/courses/ENV149/ozonation.htm.[Last accessed 2011 Feb].

12. Delvin D. The Mini-pill--Progesterone-only Pill or POP. Net Doctor, 2011. Available from: http://www.netdoctor.co.uk/sex_relationships/facts/mini-pills.htm.[Last accessed 2011 Feb].

13. Smithson J. Progesterone-onlyPill. Gp-training.net.Available from: http://www.gp-training.net/protocol/gynaecology/contraception/pop.htm.[Last accessed 2011 Feb].

About the Author

Nicola King goes to school in Canterbury. She studies Maths, Physics, Biology, and Art, and hopes to study Biology at University one day. The interest for this article started when she read an article in the news about the male roach fish turning female.

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Review Article

The evolution of atomic theory

ABSTRACT Imagine that the world around us is made of an uncountable number of small units. Up until 200 years ago, this was pure, perhaps ridiculous speculation. Now it is a widely accepted theory and we call these units atoms. In fact, it is believed that these units are made up of further, smaller units. How have we come to such a conclusion from just two centuries of experimentation?

Allen ZhengPalo Alto High School, Palo Alto, California, United States. E-mail: [email protected]

DOI: ***

The Beginning of Atomic Theory

The composition of matter is a question fundamental to our understanding of the world. Many once thought that matter could be split up into infinitesimal pieces; in fact, until the 19th century, the answer to the question remained largely speculative. However, in the years 1803–1807, John Dalton, an English schoolteacher, carried out several experiments based on the laws of conservation of matter and of definite proportions.[1] The flaws in Dalton’s conception of the atom were gradually corrected by other scientists, and the atomic model still undergoes modification as new discoveries are made.

Thomson’s Model and Rutherford’s Correction

The first formal model of an atom was put forth by British scientist J. J. Thomson in 1897, who proposed that an atom consisted of a sphere of positive charge, with negatively charged electrons dotted within it [Figure 1]. It was nicknamed the ‘plum-pudding’

model, as it represented an atom as a positively charged mass with electrons randomly laid about inside it, much like raisins in a cake[2] (Thomson is also credited with the discovery of the existence of electrons through an experiment involving the deflection of cathode rays with a magnetic field[3]). However, this model was disproved by Ernest Rutherford in an experiment in which α-particles (positively charged products of nuclear radiation) were passed through extremely thin gold foil (only several thousand atoms thick) [Figure 2]. According to Thomson’s model, all of the particles should have been deflected very slightly or not at all by the gold atoms. However, a tiny number of particles were deflected sharply. Rutherford remarked that it was ‘almost as incredible as if you had fired a 15-inch shell at a piece of tissue paper and it had bounced back and hit you!’ Rutherford’s revised model therefore consists of an extremely small, dense region in the atom with a positive charge called the nucleus that contains nearly all of its mass, while the rest of the volume is empty space in which electrons move around the nucleus. This explains the sharply deflected particles, as the nucleus had both the mass

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and the concentration of positive charge to deflect α-particles.

Bohr’s Model

Rutherford’s model was accurate in that atoms do have nuclei, but the nature of electron movement about the nucleus was still undetermined; most scientists at the time believed electrons orbit the nucleus the way planets orbit the sun. This idea was confronted by Niels Bohr using the idea that energy is quantized. That is, there is a minimum amount of energy called a ‘quantum’ that can be transferred. This is equal to the amount of energy contained in a single photon. He further proposed that classical laws of physics were inadequate to explain the nature of electron movement, reasoning that if the laws were true, electrons would spiral into and collide with the

nucleus. Using the hydrogen atom for simplicity’s sake, Bohr’s model assigns energy levels where electrons exist, and states that unless they are in those energy levels, electrons radiate energy until they enter an ‘allowable’ energy level [Figure 3]. This was the beginning of the modern model of atoms involving discrete energy levels held by the electrons. However, the Bohr model still had severe shortcomings in its inability to predict the behavior of more complex atoms.

Schrödinger’s Model and the Heisenberg Uncertainty Principle

Based on Louis de Broglie’s theory of the wave–particle duality of matter, Erwin Schrödinger expanded upon the Bohr model of the atom. Specifically, Schrödinger formed an equation describing the movement of electrons by treating electrons as waves instead of particles.[4] As electrons are evaluated as wave functions, the model assigns probabilities to

Figure 1: J.J. Thompson’s model of an atom [Available from http://upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Plum_pudding_atom.svg/220px-Plum_pudding_atom.svg.png]

Figure 2: An image depicting Rutherford’s experiment [Available from http://www.rsc.org/chemsoc/timeline/graphic/1911_gfoil_02.jpg]

Figure 3: A diagram illustrating Bohr’s model [Available from http://www.sciencekids.co.nz/images/pictures/chemistry/hydrogenatom. jpg]

Figure 4: A diagram illustrating the ‘electron probability density function’ [Available from http://lionsgensci.wikispaces.com/file/view/I15-53-quantum.jpg/137474757/I15-53-quantum.jpg]

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where an electron could be at any given time, forming an ‘electron probability density function’ around the nucleus rather than defining the specific location of an electron [Figure 4]. This uncertainty was looked into by Werner Heisenberg, who proposed that due to the dual nature of matter, there exists a fundamental restriction on the ability to know both the momentum and location of an electron at the same time. Only one could be found at any point in time for any given electron. Therefore, rather than making precise claims about the location and movement of each electron, the modern model assigns probabilities to these results.

Modern Applications of Atomic Theory

Atomic theory plays an important role in both physics and chemistry. By examining the behavior of electrons, scientists have formed cogent explanations for relatively new insights such as the configurations of complex molecules, bonding behavior, and molecule polarity, as well as explanations for more common phenomena such as water tension. Chemists and physicists after Rutherford have also

About the Author

Allen Zheng is 17 years old and currently attends Palo Alto High School. He participates in contest mathematics, debates at the national level, and plays tennis recreationally. He especially enjoys math, chemistry, and physics classes in school.

performed similar experiments to Rutherford and his colleagues on a different scale, bombarding radioactive elements with neutrons to form elements that, as far as we can tell, do not exist naturally. By examining some of the smallest particles in the universe, scientists have even managed to create some of the most powerful sources of energy, as well as the single most destructive weapon known to man.

References

1. Dalton J. On the Absorption of Gases by Water and Other

Liquids, in Memoirs of the Literary and Philosophical Society of

Manchester, 1803. [Retrieved on 2007 Aug 29].

2. Thomson JJ. On the structure of the atom: An investigation of

the stability and periods of oscillation of a number of corpuscles

arranged at equal intervals around the circumference of a circle;

with application of the results to the theory of atomic structure.

Philos Mag 1904;7:237.

3. Thomson JJ. Cathode rays ([facsimile from Stephen Wright,

Classical Scientific Papers, Physics (Mills and Boon, 1964)]).

Philos Mag 1897;44:293.

4. Schrödinger E. Quantisation as an eigenvalue problem. Ann

Phys 1926;81:109-39.

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ABSTRACT

Background on GMOs

In 1972, researchers spliced DNA from a virus and a bacterium together to create a “recombinant” molecule. Such a hybrid molecule combines traits from two different organisms to form a new genetic code. Scientists eventually discovered an innovative way of genetically modifying plants by inserting antibiotic-producing DNA into a bacterium and allowing it to “infect” plants, thus transferring the antibiotic producing capabilities to the plant’s genetic code. Since then, methods of artificial gene insertion have developed, including using a microsyringe to inject DNA molecules and a “gene gun” that fires DNA-coated metal particles into the cell.[1]

In the 1990s, the agricultural industry began offering biotech crops to the public. One such product was the FlavrSavr tomato which could retain its firmness for longer and thus boasted an extended shelf-life [Figure 1]. In nature, tomatoes contain a gene producing enzymes which decompose the structural pectin in the fruit. By reversing the gene to block enzyme production, food scientists created a tomato that could ripen without

softening.[1] Today, the most prevalent GM (genetically modified) crops are soybeans containing bacterium genes that allow the crops to resist herbicides sprayed onto fields. Another example is Bt-corn, engineered to produce Bt (Bacillus thuringiensis) proteins that provide resistance to insects. GM corn came under

Should we promote the widespread consumption of biotech foods?

Review Article

Karen WangLynbrook High School, San Jose, California, E-mail: [email protected]

DOI: ***

Genetically modified organisms, or GMOs, can be engineered to resist disease, produce more vitamins, and even provide lifesaving vaccines. Recently, scientists have been experimenting with modifying plant and animal genes to create new breeds of crops and livestock that grow faster, provide more nutrition, and minimize pollution. Why, then, are some citizens and experts hesitant about promoting the widespread consumption of these “biotech” foods? As shall be made clear, there are significant drawbacks to this agricultural innovation. As both national and worldwide consumers, we must ask if the benefits outweigh the risks of GMOs in terms of health, environment, economy, and ethics.

Figure 1: Image of a FlavrSavr Tomato (Available from http://inhabitat.com/gmo-tomatoes-could-stay-fresh-for-over-a-month/)

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attack in 2009 when a study claimed that ingestion of Bt-corn could lead to liver, kidney, and heart damage in mammals.[2] The results were dismissed by food safety authorities, who cited natural variation as the cause. However, this is neither the first nor the last time the safety of GMOs will be contested.

Health and Safety Issues

The fact remains that GM crops could be potentially harmful to human health. In 2000, a genetically engineered feed corn known as Starlink corn contaminated many corn-based processed foods. Starlink, which was not approved for human consumption, reportedly caused allergic reactions among many consumers, raising concerns about the safety of producing GMOs.[2] Numerous research projects spanning several decades claim that biotechnology is no riskier than conventional planting methods, which are also subject to contamination. In fact, GMOs might even be safer, as antibiotic-producing plants could resist potentially deadly Escherichia coli breakouts.[1] Nevertheless, opponents are still worried about the possible toxic effects of GMOs on the human body, especially concerning the growth hormone use in the milk industry.

One of the largest biotech food companies, Monsanto, injects dairy cows with the bovine growth hormone known as recombinant bovine growth hormone (rBGH). rBGH is used in a third of cows nationwide, and increases milk production by as much as 15% – a great benefit to American farmers. But its use is banned in 15 European nations as well as in Canada. Health Canada cites the issue of safety in both humans and cows, as cows injected with rBGH show higher levels of insulin-like growth factor 1 (IGF-1), a tumor-inducing substance. In addition, a report conducted by Monsanto itself shows that some rats fed with rBGH absorbed it into their bloodstream, suggesting a similar and potentially toxic effect in humans.[2] Although the Food and Drug Administration of the United States of America (USA) claims that the hormone is safe for cows and humans, a long-term study on the possible toxicity of rBGH has yet to be conducted. However, before this has been carried out, distrust in GM animals injected with hormones has led many consumers to switch to organic milk.

Worldwide Benefits

But, biotechnology holds promising applications on a global scale, which cannot be ignored. GM crops have great potential in alleviating world hunger, as scientists

have found new ways to make plants more nutritious and easier to grow. “Golden Rice” is a new breed of rice containing genes from daffodils and bacterium, which produce vitamin A. Set to be released in 2013, this could lower the malnutrition rates in citizens of third-world countries, who often lack essential vitamins.[1] In addition to providing more nutrition, GM organisms could possibly be used as edible vaccines in third-world countries that need vaccines but lack the resources and medical workers to distribute them. Harmless pathogen genes inserted into foods like bananas and potatoes would enter the patient’s digestive tract, allowing them to develop immunity to diseases including malaria and measles. While normal vaccination procedures require refrigeration, syringes, and needle sterilization, foods incorporated with medicines are easily distributable and could prevent millions of deaths in vulnerable areas like the African Congo.[1]

Advances in GMO Animals

Although genetically modified livestock remains a controversial topic, scientists are finding innovative ways to utilize this technology. In recent years, USA’s Agricultural Department has been experimenting with cows and pigs to produce disease-resistant livestock and leaner meat, which would be beneficial to both farmers’ wallets and consumers’ waistlines. In the latest advancement, scientists at Aqua Bounty Technologies have combined genes from Chinook salmon and ocean pout fish to create a breed of salmon that grows twice as fast as normal salmon [Figure 2].[3] Since faster production leads to cheaper market prices, more Americans will be able to afford this fish that supplies heart-healthy omega-3 fatty acids.

Phosphorus in livestock manure has always been a problem in the farming industry, as it contaminates the run-off and pollutes nearby rivers and lakes. Recently, researchers are experimenting with transferring enzyme-producing genes from bacteria into pigs.[3] These genes allow the pigs to digest more phosphorous and thus produce less toxic manure. This would reduce the number of fish killed as a result of algal blooms, a harmful by-product of conventional farming methods.

Economic and Environmental Effects

Genetically modified plants can translate to less pesticide and fertilizer usage in the agricultural industry, as GMOs produce their own insect repellents and growth hormones. Moreover, a recent study published

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About the Author

Karen Wang is currently a senior at Lynbrook High School in San Jose, California. She is studying computer science, statistics, Japanese, physics, economics, and contemporary literature. As hobbies, she participates in the Japanese Honour Society, Women in Science, Aikido, and Character Design clubs at school. She also enjoys watching anime and reading TIME Magazine. In addition to her studies in biology and chemistry, Michael Pollan’s books such as The Omnivore’s Dilemma and The Botany of Desire first sparked her interest in biotech agriculture. In the future, she hopes to pursue a career in either technology or engineering.

in Science magazine shows that GM corn [Figure 3] has benefitted American farmers with US$ 6.9 million since its introduction.[2] This is not surprising, as the genetically modified corn produces its own pesticides which results in less crop damage. Yet, opponents cite the various ways that GMOs could harm the environment. Pesticide-producing plants could kill beneficial insects such as ladybugs. Introducing disease-resistant crops might inadvertently create new, mutated super-viruses. Also, cross-pollination between wild plants could generate invincible weeds, such as the 1998 case where bio-engineered canola from a Canadian farm spread into the wild, requiring four herbicides to finally kill it.[1] If

GMOs escape into the wild and spread undesirable genes to their wild counterparts, it could possibly cause the extinction of other native species. Therefore, while biotech foods can reduce pollution and lower costs for farmers, they must be strictly regulated to ensure that GMO genes do not spread into the wild.

Conclusion

Through the ever-expanding field of genetic research, scientists have discovered how to insert, replace, and combine DNA in a plant or animal to produce useful traits and eliminate undesirable ones. GMOs can help to lower global hunger and disease mortality rates, reduce environmental pollution, and increase farmers’ income. However, they also pose health and safety risks, and are potentially harmful to the environment, so the production and distribution of GMOs must be tightly regulated. For example, policy-makers should require studies on the long-term side effects of GMO foods before approving them for the market.

Lastly, and perhaps most importantly, we must face the moral dilemma of such a technology – are humans justified in altering an organisms’ most intimate characteristic, its genetic code? In the future, will research extend beyond plants and animals to humans as well? One answer remains clear: As we continue to progress in all fields of science, we must uphold responsibility and consider the consequences of each technological advancement.

References

1. Hosansky D. Biotech foods. CQ Researcher 2001;11:249-72. Available from: http://library.cqpress.com/cqresearcher/cqresrre2001033000. [Last accessed on 2012 Apr 5].

2. Genetically Modified Food. Wikipedia, the Free Encyclopedia, 2011. Available from: http://en.wikipedia.org/wiki/Genetically_modified_food. [Last accessed 2011 Aug 24].

3. Pollack A. “Without U.S. Rules, Biotech Food Lacks Investors.” The New York Times, 30 July 2007, New York ed., A1 sec. Web. 23 Aug. 2011. Available from: http://www.nytimes.com/2007/07/30/washington/30animal.html. [Last accessed on 2012 Apr 5].

Figure 2: Image of salmon genetically engineered to grow twice as fast as normal (Available from http://www.nytimes.com/2007/07/30/washington/30animal.html?adxnnl=1andadxnnlx=1313859791-dEvFJk/A2YL/0AWiv7hCgAv)

Figure 3: Image of Bt-corn (Available from http://www.ipm.iastate.edu/ipm/icm/1998/1-19-1998/btdiscon.html)

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ABSTRACT

Darwin’s Theory of Evolution by Natural Selection

• When Darwin visited the Galapagos Islands in 1833, he discovered that there were several different species of finches, all closely related but with different sorts of beaks. Each type of finch was found on a different island with different food sources, and their beaks were seemingly adapted to those different food sources. These finches were the basis of Darwin’s evidence of natural selection [Figures 1 and 2].

Applying Darwin’s Theory to Drug Resistance in Bacteria

• In a colony of bacteria, a few individuals will have a natural resistance to an antibiotic drug caused by random genetic mutation. When an antibiotic such as penicillin is used, some of the bacteria will survive as a result of this resistance.

• When the surviving bacteria breed, they will pass on their property of resistance to the next generation of bacteria.

• This means that more and more of the bacteria will have a resistance to the drug [Figure 3].

Dangers of Drug Resistance in Bacteria

• Having drug resistance in bacteria is dangerous because it means infections are a lot harder to cure.

• It also means that the bacteria can spread more easily in ideally sterile environments, such as hospitals.

• One of the worst problems is that as bacteria become more resistant, you need to give them stronger doses of antibacterial drugs to kill them off – some people do not realize this and use weaker doses to treat already resistant bacteria, which just gives them a stronger resistance by means of the selection process.

• Antibacterial drugs are also sometimes mistakenly used against viruses, which have no effect on the viruses and instead make bacteria in the surrounding body more resistant to that type of drug.

Case Study: Klebsiella pneumoniae

• In August 2000, at Tisch Hospital in New York, a bacterium called Klebsiella pneumoniae was found that was resistant to almost every

Evolution of drug resistance in bacteria

Review Article

Jake Shepherd-BarronThe King's School, Canterbury, UK. E-mail: [email protected]

DOI: ***

This article explains the evolutionary mechanisms behind bacterial resistance to drugs. It uses Klebsiella pneumoniae, rod-shaped bacteria found in human and animal flora of the mouth, skin, and intestines, as an example of antibiotic-resistant bacteria.

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meaningful antibiotic Tisch Hospital had.[1] The only drug it was sensitive to was colistin, which had been abandoned as a treatment because of its potential to damage the kidneys [Figure 4].

• K. pneumoniae can survive in water and on inanimate objects. As humans, we can carry it on our skin and in our noses and throats, but it is most often found in our feces, and this is the most common method of infection in intensive care units.

• Klebsiella bacteria have a sugary coat, which makes it difficult for white blood cells to engulf them in order to destroy them.

• K. pneumoniae does not usually harm healthy people, but people who have conditions such as liver disease or severe diabetes, or those who are recovering from major surgery, are more likely to fall ill from a K. pneumoniae infection.

• The bacteria can travel deep into the lungs where they destroy the alveoli, resulting in hemorrhages. Klebsiella can also attach to the urinary tract

Figure 4: Klebsiella pneumoniae (Available from http://upload.wikimedia.org/wikipedia/commons/9/9e/Klebsiella_pneumoniae_01.png)

Figure 3: Antibiotic resistance as a result of natural selection (Available from http://upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Antibiotic_resistance.svg/500px-Antibiotic_resistance.svg.png)

Figure 1: Antibiotic test plate containing Staphylococcus aureus (Available from http://upload.wikimedia.org/wikipedia/commons/5/59/Staphylococcus_aureus_%28AB_Test%29.jpg)

Figure 2: Darwin’s finches (Available from http://upload.wikimedia.org/wikipedia/commons/a/ae/Darwin%27s_finches_by_Gould.jpg)

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About the Author

Jake is 16 and is a student of The King’s School, Canterbury, in England. He enjoys all three sciences as well as maths, and hopes to become a veterinarian later in life. Jake is not particularly into sports, although he does love non-competitive swimming, skiing, and water skiing. Jake also enjoys reading as well as the natural world (birds, insects, etc.), having grown up in the countryside. He also plays the violin and piano.

and infect the kidneys. When the bacteria get into a person’s bloodstream, they release a fatty substance known as an endotoxin, which damages the lining of the blood vessels and can cause a fatal shock.

Other Bacteria that are Resistant to Drugs [Figures 5 a-d]

• Salmonella• Escherichia coli• Staphylococcus aureus

• Streptococcus• Enterococcus• Pseudomonas aeruginosa• Clostridium difficile• Acinetobacter baumannii

Reference

1. Woodford N, Tierno PM Jr, Young K, Tysall L, Palepou MF, Ward E,et al. Outbreak of Klebsiella pneumoniae producing a new carbapenem-hydrolyzing class A β-lactamase, KPC-3, in a New York Medical Center.Antimicrob Agents Chemother 2004;48:4793-9.

Figure 5a: Salmonella

Figure 5c: Enterococcus_histological_pneumonia

Figure 5b: Escherichia coli

Figure 5d: Clostridium difficile

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Opinion

The truth behind animal testing

ABSTRACT For many, animal testing invokes an image of some large cosmetic company applying undeveloped products to unsuspecting creatures, regardless of the consequences. However, the fact is that animal testing plays a vital role in industries and research such as in the first stages of pharmaceutical trials. In many cases, models and cell samples are just not as good as whole organisms. There is still a great deal of disagreement over whether animal testing should take place and to what extent. Some of the current viewpoints are represented in the following article.

Shany SunSchool: Lynbrook High, CA, USA. E-mail: [email protected]

DOI: ***

strict regulations which govern animal care. While alternatives to animal research exist, these do not provide researchers with as much useful information as vivisection.

Opposition

Many organizations, such as the People for the Ethical Treatment of Animals, actively condemn the cruel treatment of animals in medical research. However, the National Institute of Health (NIH) and the U.S. Department of Agriculture (USDA) have strict regulations for animal testing. The NIH funds over half of the medical research conducted in the US[5] and regularly visits research facilities to ensure that staff are following animal care regulations. The USDA surveys the total number of animals being used for research and how many of these animals experience pain. According to them, only 6% of animals being tested experience pain.[6] The Animal Welfare Act of 1966 is one of the laws that regulates animal care in

Upon learning that he won the Nobel Prize for medicine for his organ transplant research, Dr. Joseph Murray said, ‘None of this could have been done without animal experimentation. It is a tragedy and a waste of resources that scientists have to combat the anti-vivisectionists.’[1] Controversy surrounding animal testing first started in the 17th century, when physiologist Edmund O’Meara and his supporters argued, ‘the benefit to humans (does) not justify the harm to animals.’[2] However, on the other side, Claude Bernard, known as the ‘father of vivisection,’[3] argued thus: ‘experiments on animals … are entirely conclusive for the toxicology and hygiene of man… the effects of these substances are the same on man as on animals, save for difference in degree.’[4] Although many people are against animal testing for medical and drug research, I believe animal testing is necessary because there has been a lot of medical knowledge gained from this experimentation. Animal rights activists protest against the inhumane treatment of animals, but animals in research facilities are actually treated quite well, in accordance with the

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research and exhibitions. This act is enforced by the USDA and the Animal and Plant Health Inspection Service. Groups such as the Use Committee and Animal Care were formed through this act. They aim to guarantee that allowing facilities to test substances on animals is a last resort, to be condoned only after other methods have failed or been deemed unsuitable. These committees are also responsible for providing the animals with medical care and good living conditions whilst undergoing experimentation. Animal testing protesters make it seem as though animals are being treated badly on a regular basis, but in reality cases of mistreatment are rare. Tom Still, president of the Wisconsin Technology Council, states, ‘Information about the true extent of animal research – and its benefits for humans and animals alike – deserves to be heard above the bullhorns and protest signs.’[7]

Benefits

Animal research makes it possible for new drugs and vaccines to be developed, benefiting both animals and humans. For example, one of the most famous cases of animal experimentation is Louis Pasteur’s chicken cholera experiment. Pasteur [Figure 1] acquired some of the cholera bacteria and infected some chickens with it. His assistant, Charles Chamberland, was supposed to inject the chickens with the bacteria again while Pasteur was on holiday, but Chamberland did not follow Pasteur’s instructions and went on vacation himself. When they came back, the month-old bacteria were injected in the chickens, but instead of making the chickens sicker, the chickens recovered completely from their disease. [8] Pasteur then created a weaker

strain of anthrax in 1881 in hopes of recreating the results of the cholera experiment[9] and found that the same method worked, thus finding the vaccine for both cholera and anthrax. Some other medical advancements that have been discovered through animal testing include penicillin, blood transfusions, insulin (that controls blood sugar levels of diabetics), kidney transplants, and vaccines for polio and meningitis.[10] Over 160 drugs and vaccines discovered by animal testing have been developed and approved by the U.S. Food and Agriculture Administration.[7] Almost every cure or vaccine that is known today is associated with animal testing. Cures for animals have been discovered, too. For example, vaccines for rabies, anthrax, feline leukemia, and canine parvo virus have been found.[11] According to the U.S. Department of Health and Human Services, animal testing has helped increase human life by 23.5 years.[12]

Alternatives

Tissue culture [Figure 2] and computer modeling are two examples of the alternatives that scientists can use. These could be used to replace animal testing, but (as I have already asserted) they do not provide as much information as animal testing. Tissue culture is a process where scientists take live tissue from a human or animal, and they test the chemical on that tissue. The problem with this type of testing is that it only shows the reactions of that group of tissues. Therefore, tissue culture tests do not show full-body reactions. Computer modeling is where scientists use a computer program to test a chemical. However, the information that scientists enter is based only on assumptions. Furthermore,

Figure 1: Louis Pasteur [Available from http://jnm.snmjournals.org/content/49/Suppl_2/24S/F9.expansion]

Figure 2: Tissue culture [Available from http://upload.wikimedia.org/wikipedia/commons/9/97/Tissue_culture_vials_nci-vol-2142-300.jpg]

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the reactions are the same every time the chemical is tested because the input is the same every time. Computer modeling does not show how a living body would react to the test. According to the John Hopkins Center for Alternatives to Animal Testing, scientists say we simply do not yet understand the complexities of the human body well enough to be able to design suitable non-animal alternatives. [13] On the other hand, Russell and Burch’s ‘The Principles of Humane Experimental Techniques’[14] lists the ‘Three R’s’ of animal testing: reduction, replacement, and refinement. These three principles can be used to improve the animals’ conditions. For example, scientists can reduce the amount of animals used in research while gaining the same amount of information. They can replace animals when it is possible to, like what the Use Committee and Animal Care groups do. Finally, researchers can refine their methods by minimizing pain for animals and giving them better living conditions.

Conclusion

Animal testing is one topic that many people do not understand. It is thought that the animals are being harmed and therefore animal testing is bad. But what these people do not appreciate is that animal testing has significantly benefited medical research; animals are not treated cruelly in the majority of cases and the alternatives are not as desirable. Many protesters will be holding up signs and yelling, ‘Stop testing now!’ every time a new research facility is constructed, but I believe we should follow the lead of Pro-Test, an Oxford-based group that is standing up for animal research and science. In the future, more and more vaccines will be developed, resulting in the treatment of more and more diseases. As Jocelyn Elders, former US Surgeon General, explains, ‘The use of animals in biomedical research and testing has been, and will continue to be, absolutely critical to the progress against AIDS and a wide range of other applications in both humans and animals.’[15]

References

1. Animal Rights.: West’s Encyclopedia of American Law. 2005. Encyclopedia.com. Available from: http://www.encyclopedia.com. [Last Accessed on 2012 May 14].

2. Ryder RD. Animal revolution: Changing attitudes towards speciesism. Oxford, England: Berg Publishers; 2000. p. 54.

3. Vivisection: When Man Turns Monster La Vivisection - Dissection Animale. Available from: http://www.artezia.net/animaux/vivisection/vivisection-gb.htm. [Last Accessed on 2012 May 14].

4. LaFollette H, Niall S. Animal Experimentation: The Legacy of Claude Bernard. University of California, San Diego. Available from: http://mechanism.ucsd.edu/teaching/philbio/Animal%20Experimentation%20The%20Legacy%20of%20Claude%20Bernard.htm. [Last Accessed on 2012 May 14].

5. Fact Sheet: Primates in Biomedical Research. California Biomedical Research Association. Available from: http://ca-biomed.org/pdf/media-kit/fact-sheets/FS-Primate.pdf. [Last Accessed on 2012 May 14].

6. Kanade S. Animal Testing Statistics. Buzzle.com, 17 Oct. 2011. Available from: http://www.buzzle.com/articles/animal-testing-statistics.html. [Last Accessed on 2012 May 14].

7. Still T. Animal Testing: Beyond the Protests, Instances of Mistreatment Are Rare. WTN News. WTN News, 21 Nov. 2005. Available from: http://wtnnews.com/articles/2489/. [Last Accessed on 2012 May 14].

8. Sternberg GM. A Textbook of Bacteriology. New York: William Wood and Company; 1901. p. 278-9.

9. Louis P. History Learning Site. Available from: http://www.historylearningsite.co.uk/louis_pasteur.htm. [Last Accessed on 2012 May 14].

10. RDS and Coalition for Medical Progress. Medical Advances and Animal Research. RDS and Coalition for Medical Progress; 2007. Print.

11. Boerner P. Animal research: How it benefits both humans and animals. California Veterinary Medical Association. Available from: http://www.cvma.net/doc.asp?ID=2403. [Last Accessed on 2012 May 14].

12. PCRM Opposes Animal Research. Physician Scam. The Physicians Committee for Responsible Medicine. Available from: http://physicianscam.com/articles/research.cfm. [Last Accessed on 2012 May 14].

13. FAQs (Frequently Asked Questions). Johns Hopkins Bloomberg School of Public Health. Available from: http://altweb.jhsph.edu/resources/faqs.html. [Last Accessed on 2012 May 14].

14. Three Rs. Animal Ethics Infolink. A NSW Department of Primary Industries and Animal Research Review Panel Initiative. Available from: http://www.animalethics.org.au/three-rs. [Last Accessed on 2012 May 14].

15. Research Facts: Quotations. Partners In Research. Available from: http://partnersinresearch.wordpress.com/health-research/research-facts/. [Last Accessed on 2012 May 14].

About the Author

Shany Sun is currently a junior at Lynbrook High in San José, California. She is currently taking AP Biology and has found the class highly interesting and engaging.

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Original Research

Bringing back Betzuca Torrentto life: The bird cages project

ABSTRACT A group of Spanish students observe birds in Betzuca Torrent and accordingly set up nesting boxes.

Eva Crespo, Neus Figols, Anna Junyent, Elena Dibarboure, Katherine Morel, Marta Díaz, Mar Fernández, Marta Sabaté, Sallatyel Carvalho, Albert Soto

IES Sant Quirze, Sant Quirzedel Vallès, Barcelona, Spain. E-mail: [email protected]

DOI: ***

One year ago, a group of 15-year-old students started a project with the following aims: To increase their knowledge about the natural system of the Galliners Hills and the Betzuca Torrent, to encourage their interest in nature, and to defend the town environment.

The relevance of this project comes from the fact that it is impossible to defend an environment without a deep knowledge about it. We had meetings every Tuesday at noon with our Environmental Educator (Neus Fígols) and our Biology and Geology teachers (Jordi Roldán and Xavier Juan). During the first sessions, we learnt about the ecological importance of the Galliners Hills as a biological connector between two Natural Parks, as well as its wealthy flora and fauna; unluckily, its environmental health is not very good. The group identified the main agents responsible for this situation: a forest fire in 1994 and anthropic pressure (such as extensive building). Then, we moved to the area of Betzuca Torrent to study the SQVnatura (Sant Quitzedel Vallès Natura) project, which is attempting to recover this fluvial space, where long ago migrant birds used to stop for a rest and drink water.

The first time we went to the hills we realized that the

trees were very young because of the 1994 fire. So, many birds such as tits (Parus spilonotus), the short-toed treecreeper (Certhia brachydactyla) [Figure 1], and the European scops owl (Otusscops) do not have enough holes to nest in.

Our task was then to install a number of bird cages to provide them with places to nest in and a night shelter for the cold winter nights. We focused on three tit species, little insectivore birds that we knew had, in previous years, used the bird cages to nest without problems.

We learnt how to identify the birds living in this area, how important they are for the environment, and how we could help with our bird cages project. We also studied the reproductive cycle of birds in order to decide the most suitable months to have the bird cages hanging in the trees of the forest. Our plan was to monitor the birds’ activity around them. We focused mainly on physical aspects such as their size, feathers, eggs, and excrement: all of them are key clues in identifying signals of life around the cages.

During our first field trips, we had to learn how to work with the cages – how to hang them up and take

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them down. We also had to decide the most suitable places to install them. Once we had decided on their locations, we recorded them with the help of a GPS device and identified each one with a number. During the breeding time (March-June), we monitored the activity in the cages. We tried to identify the presence of tits near the cages and we looked for excrement on the ground. We also took notes that could provide us with relevant information about the reproductive habits of these birds, as well as how successful the cages were in preserving this species in our area.

Once we had finished our first campaign, we felt very positive about it. We learnt a lot about the tits and the importance of their conservation for the health of the ecosystem. We also learnt to work as a team, to coordinate our efforts, and to be responsible with a project that is relevant to our community.

We enjoyed working in the field, a key activity for

science, and we hope this will contribute to our development as responsible citizens. Most of us are continuing with this experience and a number of new pupils have joined it this year. One of the main problems is that we think that 1 h per week is not enough and the fact that when the school term finishes, our activity as a group also stops.

Tragedy in a Bird Cage – Who Killed the Little Tit?

In September 2010, we resumed our project. We were checking the bird cages [Figure 2] and describing what we found inside. We had already checked two bird cages that contained spectacular bird nests when we found a big surprise in the third one.

When we opened the door, we found a cadaver amongst the materials that birds used for building the nest. We could clearly see the skeleton of a little bird

Figure 4: The spider

Figure 1: Short-toed treecreeper [from http://en.wikipedia.org/wiki/File:Boomkruiper1reversed.jpg] Figure 2: Checking the bird nests

Figure 3: The bird’s skeleton

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[Figure 3]. It was well exposed in a corner of the nest, just waiting for a forensic examination. We took some pictures of the scene and removed the nest for a future exhibition.When we were cleaning the bird cage to hang it up again, one of us screamed in panic, as people not familiarized with arachnids usually do when they see one of them. There it was! A spider of considerable size appeared and disappeared again intermittently while we were waiting patiently armed with a small defensive branch [Figure 4]. Finally, we saw it going out of the cage toward the protection of the ground. We took pictures of the spider and started hypothesizing about the dramatic death of the little bird in its bird cage.

About the Author

Eva Crespo likes playing sports, reading and walking in the forest. She wants to be a scientist in the future.

Jordi Roldán likes sports, music and nature; he wants to be a science teacher.

Anna Junyent loves music, nature, and writes some stories for her school. She wants to be a film director.

Marta Sabaté loves music and she has always wanted to be a teacher.

We then did some research using the picture of the spider as a clue to try and identify it. We found a candidate (Hygrolycosa rubrofasciata) that we knew was a poisonous spider often found in this habitat.

We think the spider killed the little bird, but we want you to bring forward new information, new hypotheses, and new evidence we should look for to close the case of ‘the little bird found dead in a bird cage.’

You can see a video of the spider at http://www.youtube.com/watch?v=O_jcakrgq5Y

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ABSTRACT

Introduction

Stomata are tiny pores found on the epidermis of the leaf, surrounded by guard cells.[1] Their main function is gas exchange[1] for photosynthesis and respiration. The development of stomata on the leaves of a plant is determined by interaction between different genes and environmental factors. A few studies have been conducted in order to establish a relationship between stomatal densities and given environmental factors. Research has shown that stomatal densities are controlled by environmental conditions during leaf development, but are fixed after the leaf matures.[2]

The article “The influence of light on stomatal density of a tomato” by A. P. Gay and R. G. Hurd describes their findings that plants grown under high light

intensity have more stomata per 1 mm2 than plants grown under low light intensity.[3]

The purpose of my investigation is to determine whether there is a correlation between the light intensity and the stomatal density on lavender leaves and whether the initial height of the plants influences the stomatal densities. The hypothesis is that an increase in the light intensity will lead to an increase in the stomatal density of the lavender leaf.

Materials and Methods

Materials• Four plant pots with soil• Rooting hormone• Lavender plant

The effect of light intensity on the stomatal density of lavender, Lavandula angustifolia

Original Research

Yoana PetrovaCity of Bristol College, Bristol, UK. E-mail: [email protected]

DOI: ???

The first aim of this investigation was to find whether there is a significant correlation between the stomatal density of lavender plants and the light intensity under which they are grown. The second aim of the investigation was to find out whether the initial height of the plant influences its stomatal density. Cuttings were taken from lavender plants to ensure that all the plants were genetically identical and that the only changes occurring in the stomatal density would be due to environmental conditions. Four cuttings were short (3 cm initial height) and four were tall (6 cm initial height). The cuttings were put under compact fluorescent light bulbs with four different power ratings (8, 11, 14, and 20 W). One short and one tall cutting were put under each of the four light bulbs for 28 days in order to grow them. Both the short and the tall plants showed a positive correlation between their stomatal densities and the light intensity. The correlation was statistically significant at a 0.025 significance level according to the Pearson product-moment correlation test. The short and the tall plants grown under the same light intensity did not show any statistically significant difference between their stomatal densities.

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Figure 1: The wooden box with the separations and the light bulbs

Figure 2: Nail polish impression of stomata (http://www.google.co.uk/imgres?imgurl=http://upload.wikimedia.org/wikipedia/en/d/de/Nail_polish_impression_of_stomata.jpg)

polish off the leaf. This is the leaf impression you will examine.[4]

15. Put the leaf impression on a clean microscope slide and put a cover slip over the leaf impression.

16. Put the prepared slide on a lit microscope stage.17. Observe the leaf impression under low

magnification.18. Adjust the light, the fine and coarse focus until a

clear image of the leaf can be seen.19. Change to a higher magnification of about 640×;

stomata should appear, looking like tiny pores on the leaf [Figure 2].

20. Count the stomata present in the field view at 640× magnification for short and tall plants grown at the same light intensity and different light intensities.

21. Record your results in a table.22. You require 10 readings for each short and

tall plant grown under the same light intensity. This will ensure you have enough data when performing the Mann–Whitney test to look for significant difference in stomatal density between short and tall plants grown under the same light intensity.

• Sterilized scissors• Clear plastic bags• Four fluorescent lamps of power ratings 8, 11,

14, and 20 W• Wooden box with four separate sections; the box

dimensions are 0.5 m height by 1.0 m width• Microscope• Cover slips and microscope slides• Nail polish and cellophane tape• White correction fluid• Cellophane tape

Methods1. Take cuttings from a single lavender plant. Use

sterilized scissors and cut the branches of the lavender plant at an angle of 45°.

2. Take eight cuttings in a way that four of them should be with an initial height of 3 cm (short plants) and four of them with an initial height of 6 cm (tall plants).

3. Dip the cut end of the cutting in a root hormone and place it in a pot containing soil. Place one short and one tall plant in a single flowerpot. Put a clear plastic bag, with a few holes in it, over the pot. Place the four flowerpots near the window, so that they are exposed to sunlight.

4. Water the plants every day, but not directly in the pot. Put the water in a small tray below the pot.

5. Keep the plants for 2 weeks before they develop roots. You can check whether roots have been developed by gently pulling the plant. Resistance when pulling indicates that roots have developed.

6. After the two initial weeks have passed, remove the plastic bags from the plant pots.

7. Place the flowerpots in a wooden box with four separate sections. Each of the four sections should be illuminated by a fluorescent light bulb of different power [Figure 1].

8. Leave only four old leaves on each plant and put a tiny correction fluid dot on them to mark them.

9. Switch the lights on for an average of 12 h each day. Water the plants with the same volume of water each time. Keep the plants under the lights for 28 days or until new leaves develop.

10. Collect all the new leaves formed under the light bulbs.

11. Paint a thick patch (few millimeters) of nail polish on the lower epidermis of each leaf.

12. Allow the nail polish to dry completely.[4]

13. Tape a piece of clean cellophane tape to the dried nail polish patch.[4]

14. Gently peel the nail polish patch from the leaf by pulling on a corner of the tape and “peeling” the

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Table 1: Results showing stomatal densities for both short and tall lavenders under different light intensities Light intensity (W/m2)

Initial height (cm)

Stomata under 640× Average stomata number

Stomatal density in 1 mm2 area

8 Short 6 7 7 9 9 8 8 7 8 7 7.6 275 Tall 8 6 8 7 9 7 8 9 7 9 7.8 28311 Short 13 14 11 12 12 10 11 11 10 11 11.5 417 Tall 10 11 13 12 11 11 12 11 12 11 11.4 41314 Short 15 14 15 16 15 16 14 15 16 14 15.0 544 Tall 14 15 15 16 16 17 15 16 15 14 15.3 55420 Short 19 18 19 18 17 20 19 18 18 18 18.4 667 Tall 18 18 19 18 19 18 17 22 19 19 18.7 678

23. Plot a graph of light intensity on the x-axis against stomatal density on the y-axis for the short plants and tall plants separately.

24. To calculate the stomatal density, which is number of stomata in a given area (e.g. 1 mm2), you must first find the microscope field view.

25. To find the field view, place a clear plastic ruler under low magnification (e.g. 40×).

26. Count the millimeter spaces you can see at that magnification;[5] this is the diameter of the field view at 40´ magnification.

27. To calculate field view at 640´ magnification, use the formula:[5]

high power field of view=

low power magnificationlow power field of view high power magnification 28. The field view under high magnification gives you

the diameter of the field view.

To calculate the area, use the formula:

Area = 2d

4p

, where “d” is the diameter of the field view.

In the investigation, there are variables that should be kept as controls because otherwise they may affect the investigation. The volume of water that the plants receive and how often they are watered can easily be controlled. Other confounding variables such as carbon dioxide concentration can be controlled in laboratory conditions only. However, in the experiment I conducted, carbon dioxide concentration would not be expected to vary a great deal.

Results

Using the described method, the following results were collected [Table 1] and underwent statistical analysis (below).

Pearson’s correlation coefficient[6]

• 0.978 for short plants• 0.979 for tall plants

Mann–Whitney U test[7]

• 8 W/m2, U = 44.0• 11 W/m2, U = 48.0• 14 W/m2, U = 41.5• 20 W/m2, U = 51.5

Discussion

In order to establish a correlation between the independent and the dependent variables, Pearson product-moment correlation was used for both the short and the tall plants. The null hypothesis is that there is no statistically significant correlation between the light intensity and the stomatal density on plants. To reject the null hypothesis, the calculated value for Pearson’s correlation coefficient must be greater than the critical value.

The critical value for four sets of data at a 0.025 significant level is 0.9500.[6] The values for the Pearson’s correlation coefficient for the tall and the short plants are both greater than the critical value; therefore, the null hypothesis can be rejected at a 0.025 significant level. Therefore, there is a correlation between the stomatal density and the light intensity. The correlation is positive as can be seen from Figures 3a and b.

When trying to explain the correlation, it is important to consider what stomata are in the first place and what their most important functions are. Stomata are tiny pores[1] found on the epidermis of the plants and their main role is gas exchange between the leaf and the environment. Although stomatal development is essentially controlled by different genes, the environment also has a significant effect on stomatal development.[8] Using plants that are clones in the investigation means that they all have the same genetic material and any changes in stomatal density on their leaves should be due to environmental

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factors.[9] Both light intensity and carbon dioxide concentration have been shown to influence the frequency at which stomata develop on the leaves of plants.[8] Plants can respond to changes in environmental conditions by changing their stomatal frequency. Recent research has shown that signals from older leaves can influence the development of stomata on the younger leaves.[10] In that way, if the environmental conditions to which the older leaves are exposed change, then the younger leaves can increase or decrease their stomatal density; this physiological adaptation can help the plant cope with the changing environment.

Why is the increased light intensity leading to increased stomatal density? Photosynthesis is the process by which plants synthesize glucose from carbon dioxide and water. The energy of the reaction is supplied by the sunlight. However, there are two main stages in photosynthesis – light-dependent

and light-independent stages.[11] The light-dependent stage depends on the light because the energy from the light is used to split water in the process of photolysis and excite electrons in the chlorophyll.[11]

The products from the light-dependent stage are ATP and the electron acceptor – reduced NADP.[11] The products from the light-dependent stage are fed into the light-independent stage of photosynthesis, the Calvin cycle.[11] Carbon dioxide is fixed in the light-independent stage and converted to glucose; in the Calvin cycle, the products of the light-dependent stage are needed. So, more ATP and reduced NADP will result in an increased rate of carbon fixation. If the rate of carbon fixation increases, the rate at which carbon dioxide diffuses in and out of the leaf will increase.

The light intensity is simply the energy per second per unit area carried by the incident light and it is proportional to the number of photons per second carried by the incident light.[12] Higher light intensity means more photons per second resulting in more electrons per second that would be excited during the light-dependent stage of photosynthesis, and more ATP and reduced NADP are produced. Therefore, increasing the light intensity will increase the overall rate of photosynthesis. The rate of gas exchange will increase as a result.

Coming back to the main function of the stomata, increasing the rate of gas exchange may lead to increased stomatal density on the epidermis of the leaf. The adaptation leads to higher carbon dioxide assimilation as the results of recent studies have shown.[2]

However, the energy of the incident light arriving per second is also proportional to the wavelength of the light. Therefore, the light intensity depends on the light wavelength. Plants have combinations of chlorophyll pigments[11] that absorb sunlight from the visible spectrum. The light of wavelengths 400–500 nm and 650–700 nm[11] is absorbed the most. These are blue and red light, respectively. Lavender grows well under compact fluorescent light bulbs.[13] By placing colored filters in front of the light bulbs, it can be established which color of light is most suitable for growing lavender and whether the color of light affects the stomatal density.

To determine whether there is a statistically significant difference between the stomatal densities on the tall and short plants grown under the same light intensity,

Figure 3a: A graph showing stomatal density against light intensity for the short plants

Figure 3b: A graph showing stomatal density against light intensity for the tall plants

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the Mann–Whitney U test is used. The null hypothesis is that there is no statistically significant difference between the stomatal densities of the tall and the short plants grown under the same light intensity. The null hypothesis may be rejected if the calculated value of U is equal to or smaller than the critical value. The critical value for U for 10 sets of data is 16.[7] Looking back at the results section, all the calculated values of U are bigger than the critical value, so the null hypothesis is accepted. The initial height did not seem to influence the stomatal development in my investigation.

Conclusion

Stomata are tiny pores found on the epidermis of the leaf and they are important for gas exchange between the plants and the environment. Their development is determined both by genes and the environmental conditions. The investigation showed a positive correlation, which was statistically significant at 0.025 level between the stomatal density on lavender plants and the light intensity. The initial height of the plants did not seem to affect the stomatal density and there was no statistically significant difference between the stomatal density on the short and the tall plants grown under the same light intensity.

References

1. Swarthout D, Hogan CM. Stomata, Encyclopedia of Earth, 2010.2. Schlüter U, Muschak M, Berger D, Altmann T. Photosynthetic

performance of Arabidopsis mutant with elevated stomatal density under different light regimes.J Exp Bot 2003;54:867-74.

3. Gay AP, Hurd RG.The influence of light on stomatal density of a tomato.New Phytol1974;75:37-46.

4. Biological Activities, Counting leaf stomata. Available from:http://www.biologyjunction.com/leaf_stomata_lab.htm.[Last Accessed 2010 Nov].

5. Gardner D. Measuring with a microscope, Cornell Centre for Material Research. Available from:http://www.ccmr.cornell.edu. [Last Accessed 2010 Nov].

6. Clegg F. The Pearson product moment correlation, Simple statistics. Cambridge University Press;1982. p. 186-7.

7. Clegg F. Mann-Whitney U test, Simple statistics. Cambridge University Press;1982. p. 164-6.

8. Casson S, Gray JE. Influence of environmental factors on stomatal development. New Phytol 2008;178:9-23.

9. Fulick A. Interations between genes and the environment, Edexcel AS Biology. Pearson Education Limited; 2008. p.188.

10. Miyazawa S, Livingston NJ, Turpin DH.Stomatal developmentin new leaves is related to the stomatal conductance of mature leaves in poplar (Populus trichordata x P deltoids). J Exp Bot 2006;57:373-80.

11. Fulick A. The biochemistry of photosynthesis, Edexcel A2 Biology. Pearson Education Limited;2008. p. 14-6.

12. Breithaupt J. More about photoelectricity. AS Physics A; 2008. p. 33.13. Home Harvest Garden Supply, Lavender. Available from:http://

herbgardening.com/growinglavender.htm.[Last Accessed 2007Mar 13].

About the Author

Yoana Petrova finished college this summer and completed an A Level in Biology, Chemistry, and Physics. During her second year, she did an extended project and this is what her article is based upon. Her plans for the future are to study Biochemistry at university and become a researcher or lecturer in biochemistry/chemistry or biology. At the moment, she is on her gap year and is working as a pharmacy assistant. Her job allows her to learn about the different medicines which is very interesting and could be useful in her future career. She does many activities in her free time such as rock climbing, ice skating, snowboarding, skiing, cycling, jogging, and reading books.

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Have you done a project, coursework, holiday placement, presentation in science which made you proud?

Will the files lie forgotten in your computer or USB drive? Will your displays gather dust in a corner of your bedroom or school lab? Or… would you like to consider publishing it in a science journal for others to

read and for posterity? (and being a published author looks great on your CV!)

Young Scientists Journal is an online science journal, written by young scientists for young scientists (aged 12-20). More than that, the journal is run entirely by teenagers, including a team of students at The King’s School, Canterbury, where the journal was founded, but including editors from all over the world. It is the only peer review science journal for this age group, the perfect journal for aspiring scientists like you to publish research.

Many of our authors have conducted scientific research for coursework, competitions, holiday placements or projects, just like you. We are also keen to receive shorter, review articles, and also other material such as news items, competitions, videos or cartoons. It is easy to submit your contribution by uploading it online at www.ysjournal.com and we can accept submissions in a variety of different forms, including pictures, videos and presentations.

If you would be interesting in getting more involved, and helping to run the journal, we are actively recruiting students at the moment to our Young Scientists team, editing articles, managing the website, graphic designing, helping with publicity.

Send an email to our Editorial Team Leader, Fiona Jenkinson: [email protected]

or find out more by visiting the Young Scientists facebook page.

We look forward to publishing your article!

A message to science students about publishing an article in:

Young Scientists online journal

www.ysjournal.com

Page 51: Young Scientists Journal 12

YSJ Photography Competition 2013

Last Year, Young Scientists Journal decided to run a Science Photography Competition. We had a great number of entries from Artists and Scientists alike and a number won the cash prizes. To see all of last year’s entries, head to our website www.ysjournal.com and find the link on the front page. A summary of the highlights of the competition is included in this issue.

This year, we want to do the same thing again so keep an eye out for the next Competition starting May 2013 and in the mean time, why not suggest the themes by starting a forum on our website?

Next Issue and Upcoming Events

Our next issue will be publishing presentations given at the St. Paul’s Anglo-Japanese Science Conference 2012. It promises to contain a variety of topics including artificial photosynthesis, the conservation of sea turtles, lift generation and many more.

This year, the conference is happening again at St. Paul’s Boys School, London on 8th March 2013 to include Science students from Germany, Japan and the UK presenting posters and presentations.

We’re also hoping to be present at the Danish Science Exhibition, either this year or next.

Join Us On Facebook. Follow us on Twitter

One of our goals for the coming year is to improve communications in the journal. Long term we hope to set up chat groups for authors and Editors so you can discuss and meet young people with a common interest in Science or Media. In the mean time, please join our Facebook page. If you find a Science subject interesting on the Web, why not post it there for us all to see? You could find people

with common interests or who may be able to help you understand more advanced ideas.

Our team do our best to update pages and feeds with stories of interest but ultimately if you could help us, it will make all the difference!

What is Young Scientists Journal?

Young Scientists Journal is an online science journal, written by young scientists for young scientists (aged 12-20). More than that, the journal is run entirely by teenagers, including a team of students in Kent, England, but involving editors from all over the world. It is the only peer review science journal for this age group, the perfect journal for aspiring scientists to publish research.

If you are a student wanting to submit an article, head to our website www.ysjournal.com. It can be on any Science-related subject, be it a previous science project, original research or opinion/knowledge that you would like to share. You can put this on your CV

or use it to contribute to awards such as D of E. To get even more involved as part of our editorial, technical or publicity teams, contact the current Chief Editor, Fiona Jenkinson by e-mailing [email protected]. Alternatively, find us on Facebook or Twitter, represent us at a Science Event or tell your friends about us – every little helps!

Teachers can get involved by joining our International Advisory Board and encouraging students to submit their work.

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The Butrous Foundation

The foundation aims to motivate young people to pursue scientific careers by enhancing scientific creativity and communication skills. It aims to provide a platform for young people all over the world (ages 12-20 years) to participate in scientific advancements and to encourage them to express their ideas freely and creatively.

The Butrous FoundationButrous Foundation

The Butrous Foundation is a private foundation established in 2006. The current interest of the foundation is to fund activities that serve its mission.The MissionThe foundation aims to motivate young people to pursue scientific careers by enhancing scientific creativity and communication skills. It aims to provide a platform for young people all over the world (ages 12-20 years) to participate in scientific advancements and to encourage them to express their ideas freely and creatively.

Thematic approaches to achieve the foundation mission:1. To enhance communication and friendship between young people all over the world and to help each other with their scientific interests.2. To promote the ideals of co-operation and the interchange of knowledge and ideas.3. To enhance the application of science and its role in global society and culture.4. To help young people make links with scientists in order to take advantage of global knowledge, and participate in the advancement of science.5. To encourage young people to show their creativity, inspire them to reach their full potential and to be role models for the next generation.6. To encourage the discipline of good science where open minds and respect to other ideas dominate.7. To help global society to value the contributions of young people and enable them to reach their full potential.Visit Young Scientists journal www.ysjournal.com

The Butrous Foundation

The foundation aims to motivate young people to pursue scientific careers by enhancing scientific creativity and communication skills. It aims to pro-vide a platform for young people all over the world (ages 12-20 years) to participate in scientific advancements and to encourage them to express their ideas freely and creatively.

The Butrous FoundationThe Butrous Foundation is a private foundation established in 2006. The current interest of the foundation is to fund activities that serve its mission.

The Mission

The foundation aims to motivate young people to pursue scientific careers by enhancing scientific creativity and communication skills. It aims to provide a platform for young people all over the world (ages 12-20 years) to participate in scientific advancements and to encourage them to express their ideas freely and creatively.

Thematic approaches to achieve the foundation mission:1. To enhance communication and friendship between young people

all over the world and to help each other with their scientific interests.

2. To promote the ideals of co-operation and the interchange of knowledge and ideas.

3. To enhance the application of science and its role in global so-ciety and culture.

4. To help young people make links with scientists in order to take advantage of global knowledge, and participate in the advance-ment of science.

5. To encourage young people to show their creativity, inspire them to reach their full potential and to be role models for the next generation.

6. To encourage the discipline of good science where open minds and respect to other ideas dominate.

7. To help global society to value the contributions of young people and enable them to reach their full potential, visit Young Scientists journal www.ysjournal.com

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Young Scientist Journeys Editors: Paul Soderberg and Christina Astin

This book is the first book of The Butrous foundation’s Journeys Trilogy. Young scientists of the past talk to today’s young scientists about the future. The authors were members of the Student Science Society in high school in Thailand in the 1960s, and now, near their own 60s, they share the most important things they learned about science specifically and life generally during their own young scientist journeys in the years since they published The SSS Bulletin, a scientific journal for the International School Bangkok.

Reading this first book is a journey, that starts on this page and ends on the last one, having taken you, Young Scientist, to hundreds of amazing “places,” like nanotechnology, Song Dynasty China, machines the length of football fields, and orchids that detest wasps. But the best reason to take the journey through these pages is that this book will help you

prepare for all your other journeys. Some of these will be physical ones, from place to place, such as to scientific conferences. Others will be professional journeys, like from Botany to Astrobiology, or from lab intern to assistant to researcher to lab director. But the main ones, the most exciting of all your journeys, will be into the Great Unknown. That is where all the undiscovered elements are, as well as all other inhabited planets and every new species, plus incredible things like communication with dolphins in their own language, and technological innovations that will make today’s cutting-edge marvels seem like blunt Stone Age implements.

For further information please write to [email protected]

The Butrous Foundation, which is dedicated to empowering today the scientists of tomorrow. This foundation already publishes Young Scientists Journal, the world’s first and only scientific journal of, by, and for, all the world’s youngsters (aged 12-20) who want to have science careers or want to use science in other careers. 100% of proceeds from sales of The Journeys Trilogy will go to the Foundation to help it continue to fulfill its mission to empower youngsters everywhere.

Book Details:

Title: Young Scientist Journeys

Editors: Paul Soderberg and Christina Astin

Paperback: 332 pages

Dimensions: 7.6 x 5.2 x 0.8 inches, Weight: 345 grams

Publisher: The Butrous Foundation (September 26, 2010)

ISBN-10: 0956644007

ISBN-13: 978-0956644008

Website: http://www.ysjourneys.com/

Retailer price: £12.45 / $19.95

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The Butrous Foundation Journeys Trilogy Thirty-one years ago, Sir Peter Medawar wrote Advice to a Young Scientist, a wonderful book directed to university students. The Butrous Foundation’s Journeys Trilogy is particularly for those aged 12 to 20 who are inspired to have careers in science or to use the path of science in other careers. The three volumes are particularly for those aged 12 to 20 who are inspired to have careers in science or to use the path of science in other careers. It is to “mentor in print” these young people that we undertook the creation and publication of this trilogy.

Young Scientist Journeys (Volume 1) This book

My Science Roadmaps (Volume 2) The findings of journeys into key science issues, this volume is a veritable treasure map of “clues” that lead a young scientist to a successful and fulfilling career, presented within the context of the wisdom of the great gurus and teachers of the past in Asia, Europe, Africa, and the Americas.

Great Science Journeys (Volume 3) An elite gathering of well-known scientists reflect on their own journeys that resulted not only in personal success but also in the enrichment of humanity, including Akira Endo, whose discovery as a young scientist of statins has saved countless millions of lives.

Table of Contents: Introduction: The Journeys Trilogy, Ghazwan Butrous . . . 11 Chapter 1. Science is All Around You, Phil Reeves . . . 17 Chapter 2. The Beauty of Science, and The Young Scientists Journal, Christina Astin . . . 19 Chapter 3. The Long Journey to This Book, Paul Soderberg . . . 25 Chapter 4. Dare to Imagine and Imagine to Dare, Lee Riley . . . 43 Chapter 5. How the Science Club Helped Me Become a Human Being, Andy Bernay-Roman . . . 55 Chapter 6. Your Journey and the Future, Paul Soderberg . . . 63 Chapter 7. Engineering as a Ministry, Vince Bennett . . . 83 Chapter 8. Cold Facts, Warm Hearts: Saving Lives With Science, Dee Woodhull . . . 99 Chapter 9. My Journeys in Search of Freedom, Mike Bennett . . . 107 Chapter 10. Insects and Artworks and Mr. Reeves, Ann Ladd Ferencz . . . 121 Chapter 11. Window to Endless Fascination, Doorway to Experience for Life: the Science Club, Kim Pao Yu . . . 129 Chapter 12. Life is Like Butterflies and Stars, Corky Valenti . . . 135 Chapter 13. Tend to Your Root, Walteen Grady Truely . . . 143 Chapter 14. Lessons from Tadpoles and Poinsettias, Susan Norlander . . . 149 Chapter 15. It’s All About Systems—and People, J. Glenn Morris . . . 157 Chapter 16. A Journey of a Thousand Miles, Kwon Ping Ho . . . 165 Chapter 17. The Two Keys to Making a Better World: How-Do and Can-Do, Tony Grady . . . 185 Chapter 18. Becoming a Scientist Through the Secrets of Plants, Ellen (Jones) Maxon . . . 195 Chapter 19. The Essence of Excellence in Everything (and the Secret of Life), Jameela Lanza . . . 203 Chapter 20. The Families of a Scientist, Eva Raphaël . . . 211 Appendix: Lists of Articles by Young Scientists, Past and Present . . . 229 The SSS Bulletin, 1966-1970 . . . 230-237 The Young Scientists Journal, 2008-present . . . 237-241 Acknowledgements . . . 243 The Other Two Titles in the Journeys Trilogy . . . 247 Contents of Volume 2 . . . 249 Excerpt from Volume 3: A Great Scientist . . . 251 Index . . . 273

Editors Christina Astin and Paul Soderberg

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