Young Sceintists Journal by YSJournal

Volume 4 Issue 10 Jul-Dec 2011

Special Issue : Origin of Life

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Young Scientists Journal • Volume 4 • Issue 9 • January-June 2011 • Pages 1-42

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Young Scientists Journal

Volume 4 | Issue 10 | Jul - Dec 2011

Editorial Board Chief Editor: Pamela Barraza Flores, Mexico Editorial Team Members Team Leader: Cleodie Swire, UK Phoebe Leung Nicola King Hannah Todd Rosie Ffoulkes Isobel Wingrad Harriet Cousins Fiona Paterson Chidera Ota Elizabeth Morcom Eleanor Powell Jacob Shepherd-Barron Fiona Jenkinson Chris Cundy Louis Wilson Harriet Dunn

Louis Sharrock David Hewett Arthur Harris Mei Yin Wong Chloe Chalmers Alex Lancaster Matt Harrison Joseph Keel Matthew Brady Ben Lawrence Tim Wood Robert Aylward

Technical Team Team Leader: Malcolm Morgan, UK Mark Orders, UK Jacob Hamblin-Pyke

Young Advisory Board Jonathan Rogers, UK Malcolm Morgan, UK

International Advisory Board Team Leader: Christina Astin, UK Ghazwan Butrous, UK Mark Orders, UK Joanne Manaster, USA Paul Soderberg, USA Andreia Azevedo-Soares, UK Lee Riley, USA Paul Soderberg, USA Corky Valenti, USA Anna Grigoryan, USA / Armenia Vince Bennett, USA Don Eliseo Lucero-Prisno, UK Mike Bennett, USA Linda Crouch, UK Tony Grady, USA Steven Chambers, UK Ian Yorston, UK Thijs Kouwenhoven, China Charlie Barclay, UK

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

Young Scientists Journal 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.com E-mails:editor@ysjournal.com

Volume 4 | Issue 10 | Jul - Dec 2011

Contents... Editorials Pamela Barraza Flores .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43 Cleodie Swire .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

Origin of Life From hominids to humans: An overview of the evolution of man Emma Greaves.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 46 Are we alone after all? Ana Pavlova.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48 The life-cycle of stars Cleodie Swire .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52 The role of supernovae in the origins of life Ben Maybee.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56 The Endosymbiotic Theory Cleodie Swire .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61 A review of 10 of the best Origin of Life books Fiona Jenkinson.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65

Interviews Interview with Dr. Luis Delaye Liliana Corona Martínez.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 Interview with Dr. Gabriela Olmedo Liliana Corona Martínez.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71

Review Articles A dual nature of light Maciej Bąk.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73 Melanomas and their effect on the grey horse Katherine Burden.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 75

Research Article Knowledge of HPV and cervical cancer among women in Little Haiti Paula-Suzanne Lapciuc, Nadia Willy .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82

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

Author Index, 2011

Title Index, 2011

Editorial Where do we come from? Where are we going? Who or what made life? These questions have kept us awake at night. They have for centuries intrigued the minds of the greatest scientists. From the Greeks to modern times, we have still not discovered with certainty the origin of life. It is indeed one of the most promising, intriguing, and perhaps least understood questions of the humanities and sciences. How close are we to discovering the truth? How are our lives going to change when we do? Will it set the time for a new generation of science? It is us, the new generation of scientists, who will uncover the truth. Can you, young scientist, imagine yourself discovering the biggest secret of life? In this special edition about The Origin of Life, we will travel through the ancient discoveries, modern science and beyond to find how close we are to unraveling the true meaning of this mystery. Many important theories have been conceived in human history. In this issue, we bring you a score of information in the form of articles and interviews with experts in the field. These include the best articles from our latest aptly-themed competition. The winner is entitled â&#x20AC;&#x153;Are we alone after all?â&#x20AC;?; it is a very interesting article about life on other planets. Other articles from the competition discuss the quantum world, complex cells, evolution, supernovae, and more that will bring you even closer to the origin of life. There is also a review of ten of the best books on this subject. This issue also contains articles on a wide range of other topics from coronary heart disease to questioning the compatibility of science and religion. On another subject, this is going to be my last issue as Chief Editor. I would like to thank all the editors involved and give special recognition to Professor Butrous, founder of the Young Scientists Journal, who has allowed my voice as a young scientist to be heard. Christina Astin and the Young Scientists team are an amazing group of young science communicators that are always open to collaboration from all around the world. I invite all young readers to join the team and to recruit other enthusiasts; this is a life changing experience. Cleodie Swire is already doing excellent work leading the editorial team, and will now take on the role of Chief Editor. I am sure that she will take the journal to even greater heights.

Pamela Barraza Flores Chief Editor DOI: 10.4103/0974-6102.92191

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Editorial The Young Scientists Journal is going to run a competition with the theme, ‘The Dark Ages’. We are looking for articles about many scientific advances occurring in the East during the so-called Dark Ages, which were actually a very fruitful time in the Muslim world. This theme is based on The 1001 Inventions Exhibition, and some ideas for topics are detailed below. The 1001 Inventions Exhibition, which acts to educate people about the advances in all types of technology by the Muslim communities that were going on during the so-called ‘Dark Ages’, was started by a group called FSTC, which is based in Manchester. It,initially,wasa smaller exhibition in 2006, funded by a range of sponsors, which travelled the UK and had great success. Due to this, a decision was made to develop the exhibition even further, and tour internationally. Scholars and scientists from all over the world have verified the information collected for the exhibition, which was in The Science Museum from the 21st January until the 30th June 2010, and proved to be the most successful temporary exhibition there ever. Around 10,000 people visited the exhibition per week, which is now going to Turkey, and then America. The exhibition comprises of various stations with information on advances on a diverse selection of subjects. It puts a lot of emphasis on the idea that the objects we use now only exist due to the discoveries made by the Muslim civilizations during the ‘black hole in history’ between 700 and 1700 AD. The exhibition is divided into about six sections, each dealing with a different topic: • There is one dedicated to mechanical technology, which featured the famous elephant clock and the Banu Musa brothers’ trick flask. • Another focused on education, explaining about the libraries full of handwritten books, and universities – one of which (Al-Qarawiyin in Morocco) still functions today. • Industries such as glassmaking, papermaking, and distillation are described – all paid for in early currencies, such as cowry shells in the Maldives. • Many medical methods and tools that we still rely were used in these societies, such as scalpels, drills, and forceps. Although William Harvey is credited with the discovery of the blood circulatory system, he was only elaborating on the recently-translated works of Ibn Nafis, who lived in Syria in the 13th century. • Architecture since the Dark Ages has been greatly influenced by the designs and fashions of the Middle East. • The study of the starswas something that greatly interested the Muslims, and many of the constellations still studied today were identified and named by these civilizations. One of the highlights of the exhibit is a short video featuring Sir Ben Kingsley, which demonstrates the aim of the exhibition: To educate people about the Arabic world and its heritage, which is publically ignored in comparison to Ancient Egyptian or Roman life. The video introduces some of the main characters featured in the exhibition, such as ‘Abbas Ibn Firnas, the first person to attempt to construct a flying machine, and Abul al-Zahrawi, one of the most famous Muslim surgeons of his time. There are many interactive elements to the exhibition, such as a room where you can place the constellations in the sky by pointing your hand, as well as many interactive boards.These include an exhibit to link up words in our language that are derived from Arabic sources, such as the word ‘giraffe’ which came from the Arabic ‘Zarafa’, and ‘sofa’ which stems from the word ‘suffah’, meaning ‘long bench’. Although nearly every conceivable aspect of modern life has been directly influenced by the discoveries and inventions made by the Muslims in these times, only a limited number of examples could be presented in

Young Scientists Journal | 2011 | Issue 10

the exhibition, but the book, Muslim Heritage in Our World, gives full justice to the scale of the research that has gone into the project.

Cleodie Swire Head of the Editorial Team DOI: 10.4103/0974-6102.92192

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Origin of Life

From hominids to humans: An overview of the evolution of man Emma Greaves Haybridge High School. E-mail: emmagreaves94-xo@hotmail.co.uk DOI: 10.4103/0974-6102.92193

In the last few million years or so, our earliest ancestors evolved. These ancestors were very human-like and are now known as hominids. Scientists are always discovering new fossils and links to earlier species, and the family tree is forever growing. Hominids are all different making it difficult to identify fossils and some species [Figure 1]. But where did hominids come from? And how do we know about them? Like modern humans, these hominids used stone tools, had a human-like tooth structure, and also walked similarly to us; although, unlike modern humans, the brain case was smaller. So as the hominid family diversified from apes, what happened next? Australopithecines happened next. Now we don’t have much of record of how they behaved, but we do have records of the change of the shape of the head

Figure 1: Main stature of hominid evolutionary stages [available from http://www.edupics.com/image-human-evolution-i10176.html]

to a more modern man-like shape. This species was a small species, with three distinct sub-species; they existed between three and five million years ago. It was thought that this species moved from the jungle into the open land; however, since they were not suitably adapted to this environment, they retreated back to jungle.

Australopithecus afarensis and ‘southern ape from afar’ There are not a lot of records about the southern ape from afar; however, we do know it was slender built with smaller canines and molars and a relatively small brain size. This was getting closer and closer to human kind and existed about four million years ago. Australopithecus africanus was also an early hominid, which was supposedly alive two to three million years ago and very similar to the ‘southern ape from afar’, thought to be a direct ancestor of modern humans of today. It had many similar features such as slightly larger legs than arms and human-like cranium features. Around 1.5-two million years ago, following on from the development of the hominids, the ‘homo’ species was evolved. A very obvious change in the size of the brain was present. The change in the overall species structure meant that taxonomists gave an entirely new name to this evolved species. The homo Young Scientists Journal | 2011 | Issue 10

species is a more recent link to the modern day man. The first signs of intelligence were present in the â&#x20AC;&#x2DC;homoâ&#x20AC;&#x2122; species; for example, they carved small stones to catch prey or cut branches off trees. This new-found intelligence gave them the chance to go back into the open land, much like the ambitions of their earlier ancestors. This huge advantage was natural selection in its prime, and a critical stage in the development of man. Homo sapiens, meaning wise man, were moving even closer to modern man. It exhibited a larger head and heightened intelligence. The tools they used were sophisticated and the species found new ways of adapting to its environment. It has also been found that they used wooden tools such as spears. They arrived on earth about a quarter of a million

years ago. The Neanderthals were widespread around Europe and Asia during that time; they were slowly disappearing as this new intelligent species were developing, giving opportunity to develop and adapt. Homo sapiens from 30,000 years ago to modern day, have won many battles and environmental challenges. At this point, human history is being made. So in conclusion, the human race has evolved and adapted to inhabit open land, originating from the jungle. We have developed longer legs and arms so we can walk vertically rather than horizontally, and we have also increased in intelligence along with head size.

About the Author Emma Greaves is 16 years old. She is in year 11 at Haybridge High School. She is going to study Chemistry, Biology, Maths and P.E. at A Level. She would love to be a veterinary surgeon and is working really hard to achieve this ambition. She is a competitive swimmer and loves the sport!

Author Institution Mapping (AIM)

Please note that not all the institutions may get mapped due to non-availability of the requisite information in the Google Map. For AIM of other issues, please check the Archives/Back Issues page on the journalâ&#x20AC;&#x2122;s website.

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Origin of Life

Are we alone after all? Ana Pavlova British School of Bucharest, Bucharest, Romania. E-mail: pavlova_ani@hotmail.com DOI: 10.4103/0974-6102.92196

Who to believe? Is it possible that intelligent life in outer space exists? Could it be that Earth has already been visited by aliens? Are there traces left for us to find? Is it up to us to make the first step? These thoughts have captivated mankind for centuries, and still inspire the quest to reach out, find out, and discover; despite the fact that scientists are fundamentally split on the question of whether or not life outside the Earth exists. Some believe that there are simply so many planets out there that it would be impossible for us not to find intelligent life someday. Others believe that due to the lack of evidence, we cannot accept this prospect until presented with proof. So which scientists should we agree with? Those for or those against? Throughout history, our predecessors have shown remarkable resistance to accepting ground-breaking concepts, greeting new ideas with denial, sometimes even persecution, only to be proven wrong eventually. There are many examples of this happening: over 2,000 years ago, Aristarchus of Samos wrote about the Earth being just one of many objects moving around the Sun, even though the modern idea of planetary orbits did not exist. His work shows geometrical calculations based on observations, showing the Sun to be much bigger than the Earth and the Moon. Even though these calculations supported his ideas, they were not accepted as true until the 17th century. And so throughout the dark ages and beyond, people continued to believe that 48

the Earth was the centre of the universe â&#x20AC;&#x201C; to say otherwise was heresy. Indeed even Copernicus and Galileo, who we celebrate today as great visionaries and seekers of truth, were severely punished for challenging the Roman Catholic Churchâ&#x20AC;&#x2122;s view that the Earth was the center of the universe.[1] So should we rule out the possibility of extraterrestrial life just because of insufficient evidence? Interestingly, some scientists believe that it is our loneliness in the universe that causes us to imagine that extraterrestrial life is possible. The universe is vast and never-ending; there are billions of trillions of stars, planets, meteors, and comets. To think of this seemingly infinite space with no intelligent life other than our own is not a comforting thought to say the least. In fact, it is positively terrifying when one really thinks about it. It has been suggested that to calm these fears, we invent stories to fill up the void beyond our solar system, in order to imbue a lifeless universe with intelligent life and thus to make it seem a more habitable and friendly place to live. On the other hand, scientists such as Carl Sagan and Stephen Hawking argue that it is exactly because the universe is so vast that it would be improbable for life not to exist somewhere other than Earth. Hundreds of planets are being discovered every year. In six weeks alone, the National Aeronautics and Space Administration (NASA), found 700 possible planets and 5 new solar systems. [2] Scientists Young Scientists Journal | 2011 | Issue 10

believe that a small group of these may be capable of supporting life. Many such planets, nicknamed ‘Goldilocks planets’ (not too cold, not too warm – the conditions are ‘just right’ to support life) have been found already; including Gliese 581 c, Gliese 581 d and OGLE-2005-BLG-390Lb, all of which have Earthlike qualities.[3] Recently, on September 29th, 2010, a new Goldilocks planet was discovered by scientists using one of the most powerful telescopes on Earth - the Keck telescope in Hawaii. Gliese 581 g lies 20 light-years away from Earth in its star’s Goldilocks zone – an area where temperatures are favourable and planets may be capable of containing water, and therefore also life [Figure 1]. This planet might be the most similar Goldilocks planet to Earth yet discovered. “The fact that we were able to detect this planet so quickly and so nearby tells us that planets like this must be really common,” commented Steven Vogt, an astronomer at the University of California Santa Cruz.[3] The planet’s average temperature is thought to be between −31°C and −12°C, and we know for a fact that there are many intelligent animals living in these types of conditions on Earth, such as polar bears, whales, and even humans (for instance the Inuit people). Dr. Vogt goes on to state that, “The number of systems with potentially habitable planets is probably in the order of 10% or 20%, and when you multiply that by the hundreds of billions of stars in the Milky Way, that’s a large number. There could be tens of billions of these

systems in our galaxy”.[3] Tens of billions of planets is a huge number. Surely we cannot be so naïve to think that we are the only intelligent life in such a vast universe? This problem has been drawing attention since the conception of the Drake equation1 in 1960. Yet, some scientists argue that if the chance of finding life were so huge, we should have found it by now. Frank Tipler, for example, has proved that, if using pessimistic numbers, the chances of finding a civilization in the galaxy is lower than one. Even Frank Drake (the inventor of the Drake equation) has stated that the Drake equation is just a way of “organizing our ignorance” on the subject.[4] On the other hand, Dr. Carl Sagan used optimistic numbers to conclude that there might be millions of civilizations in the Milky Way alone.[5] Arsenic Based Life One reason for which we have not yet found any traces of intelligent life might be because we have no idea what to look for. The key to actually finding intelligent life is to fully understand what the term means. But how do we define intelligent? Some think that any form of life that can survive should be classified as intelligent, whereas others state that even Homo sapiens cannot be placed in this category.[6] Search for Extraterrestrial Intelligence (SETI) believes that intelligent life must be able to transmit and receive signals,[7] whereas a more general definition is perhaps that intelligent life must be able to learn. Furthermore, just because we Earthlings need certain elements and compounds to survive (for example oxygen and water) it does not necessarily mean that any other intelligent life form would as well. Recently, as a matter of fact, a microorganism has been found2 which uses arsenic instead of phosphorus in its cell components. Phosphorus is essential to both DNA and RNA, which carry genetic information for life, and was until recently considered absolutely essential for all living cells. Arsenic on the other hand, despite The Drake equation is used to estimate the number of extra-terrestrial civilizations in the Milky Way galaxy with which communication might be possible. 2 A microorganism called Strain GFAJ-1 was found on 2nd December, 2010, by NASA researchers in Mono Lake in California [Figure 2]. Strain GFAJ-1 belongs to the class Gammaproteobacteria. The researchers began by giving the microbe both phosphorus and arsenic and eventually removed the phosphorus. The microorganism continued to grow, living only on arsenic. The location was chosen because of its high alkalinity and levels of arsenic, which are partly a result of Mono Lake’s 50-year isolation from a source of fresh water. 1

Figure 1: ESO. (unknown) “The star Gliese 581”. ESO. http://www.eso. org/public/images/eso0722c/ on 29-12-10. Used with permission under the Creative Commons Attribution 3.0 Unported license. http://www. eso.org/public/outreach/copyright.html

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being chemically similar to phosphorus, is poisonous to most life on Earth.[8] According to NASA, this finding will dramatically expand the search for intelligent life, as it affirms the possibility of life which does not need the same conditions as most other organisms in order to survive. “The idea of alternative biochemistries for life is common in science fiction,” said Carl Pilcher, director of the NASA Astrobiology Institute in California. “Until now, a life form using arsenic as a building block was only theoretical, but now we know such life exists in Mono Lake.”[8] This discovery also leads us to the revelation that we might not as easily recognize intelligent life forms in outer space – they could be completely different from our expectations. As Felisa Wolfe-Simone, a NASA Astrobiology Research Fellow in California and the research team’s lead scientist, stated: “We know that some microbes can breathe arsenic, but what we’ve found is a microbe doing something new – building parts of itself out of arsenic. If something here on Earth can do something so unexpected, what else can life do that we haven’t seen yet?”[8] This shows us that so far, we might have been looking for the wrong thing. “The definition of life has just expanded,” said Ed Weiler, NASA’s associate administrator for the Science Mission Directorate at the agency’s Headquarters in Washington. “As we pursue our efforts to seek signs of life in the Solar system, we have to think more broadly, more diversely and consider life as we do not know it.”[8]

Public Reaction This change of mindset presents a new question: If we were to discover intelligent life, what would the result be for us? A reaction similar to the War of the Worlds radio panic3 in 1938 could be the outcome of such news. Awe is another option. Is terror or amazement the more likely response from our side? There is also a lot of speculation as to what the intelligent life forms if found would do. Would they be friendly and wish to establish contact with us? Or is it more likely for them to be hostile and angry 50

Figure 2: Blum, J. (unknown) “GFAJ-1 grown on arsenic”. Available from: http://www.nasa.gov/topics/universe/features/astrobiology_toxic_ chemical.html on 20-12-10

for having been discovered? It is impossible to tell at this point. However, to avoid a worldwide panic, agencies and organizations are trying to prepare us, the people of Earth, for the possibility of finding intelligent life. The Search Reassured that public relations on the E.T. topic are well taken care of; scientists are free to pursue the quest to find extraterrestrial intelligent life. New projects are constantly cropping up to try and discover any trace of other-worldly intelligence. Organisations such as SETI, for example, are searching the skies for radio wave activity – if found such evidence would settle the matter and thus prove that intelligent life exists. An associated idea is that intelligent life might send laser signals into outer space. This is one of the best ways to discover other possible intelligent life forms in the galaxy – by looking for evidence of technology developed by that life. Scientists conducting the High Resolution Microwave Survey in 1992 scanned the whole sky for strong microwave signals; their logic being that at some point intelligent beings on other worlds might eventually develop radio technology capable of sending these signals. In 1993, however, the United States Congress advised NASA to end the project.[9] Nevertheless, in 1998, NASA astronomers began to search for pulses of laser light. They thought that possible intelligent creatures in outer space might have developed powerful lasers. They then may have transmitted short laser light pulses into the universe for observers, such as us, to detect.[10] Young Scientists Journal | 2011 | Issue 10

The only drawback with such space communication is that light signals must travel for thousands of light years in order to reach their destination, and it would take just as long for any reply or laser pulse to reach us. So, if we were to receive any kind of signal from outer space, it would be from the distant past, and there would be no guarantee that the life forms would be still alive. Have we reached a setback in our quest to find intelligent life in outer space? Yes. Does this mean we are going to stop searching? Definitely not. As Mark Twain put it, ‘There can’t be rainbows without rain,’ meaning that until you reach the end result, there are inevitably going to be obstacles along the way.

References 1. Finnochiaro M. “Sentence (22 June 1633)”. Available from: http://web.archive.org/web/20070930013053/http:// astro.wcupa.edu/mgagne/ess362/resources/finocchiaro. html#sentence on 12-01-11 [Last cited on 1989]. 2. QMI Agency. “700 new planets discovered by NASA”.

Available from: http://www.torontosun.com/news/ world/2010/07/25/14822461.html on 11-01-11 [Last cited on 2010]. 3. Moskvitch K. “Goldilocks planet just right for life”. Available from: http://www.bbc.co.uk/news/science-environment-11444022 on 17-12-10 [Last cited on 2010]. 4. Gowdy R. “SETI: Search for ExtraTerrestrial Intelligence”. Available from: http://www.courses.vcu.edu/PHY-rhg/astron/ html/mod/019/s5.html on 11-01-11 [Last cited on 2008]. 5. Sagan C. “Carl Sagan – Cosmos – Drake Equation”. Available from: http://www.youtube.com/watch?v=MlikCebQSlY on 2601-11 [Last cited on 1980]. 6. Watson D. (1997) – Kindly provide complete information 7. Morrison D. “What is the definition of Intelligent Life? Is it the ability to analyze situations and react in the correct way, or is the complexity the primary issue”. Available from: http:// astrobiology.nasa.gov/ask-an-astrobiologist/question/?id=918 on 19-12-10 [Last cited on 2004]. 8. Brown D, Weselby C. “NASA-Funded Research Discovers Life Built With Toxic Chemical”. Available from: http://www.nasa. gov/topics/universe/features/astrobiology_toxic_chemical.html on 20-12-10 [Last cited on 2010]. 9. New York Times reprint. Available from: http://www.war-of-theworlds.org/Radio/Newspapers/Oct31/NYT.html on 12-01-11. 10. Klein MJ. “Extraterrestrial intelligence.” World Book Online Reference Center. World Book, Inc. Available from: http://www. worldbookonline.com/wb/Article?id=ar189230. on 17-12-10 [Last cited on 2005].

About the Author Ana Pavlova was born in 1997 and lives in Romania. Her favourite subjects are Science, French and History. In her free time she enjoys playing tennis, reading, learning new things and spending time with her family; she particularly enjoys a heated debate! She hopes to study law or politics at University; however, she is still unsure as to what career path she would like to follow.

Information for Students Young Scientists Journal is a unique online science journal, written by young scientists for young scientists (aged 12-20). More than that, the journal is run entirely by teenagers. It is the only peer review science journal for this age group, the perfect journal for aspiring scientists like you to publish research. 1. Have you recently done an interesting school project? 2. Would you like to do some unique research? 3. Do you have documents written for competitions lying around on your computer? If so, you may be interested in having your article published by The Young Scientists Journal. Your article will be processed by a team of students and then an International Advisory Board before being made into an official article with its own unique code. As well as this being rewarding, it also will look very good on a CV! We are also keen to receive shorter, review articles, and creative material such as videos or cartoons. 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 for tasks such as editing articles, managing the website, graphic designing and helping with publicity. Young Scientists Journal | 2011 | Issue 10

Origin of Life

The life-cycle of stars Cleodie Swire The Kingâ&#x20AC;&#x2122;s School, Canterbury, E-mail: 07CCS@kings-school.co.uk DOI: 10.4103/0974-6102.92198

Stellar Nebula A nebula consists of dust and gas, and there are places where gravity causes these to clump together. This means their gravitational attraction to other atoms increases, pulling more atoms into the clump. The process where atoms fall into the clump and become part of the protostar is called accretion. To become a star, the protostar will need to achieve hydrostatic equilibrium by balancing the gravity, pulling atoms in, and the radiation pressure pushing heat and light out. When equilibrium is achieved, if a specific mass is not reached (around 0.08 times the mass of the Sun), the protostar will become a brown dwarf, but if this critical mass is reached, then nuclear fusion is able to begin, and the star is born, entering the main sequence [Figure 1].

that of the Sun and emit millions of times more light, but they only live for a few million years.

Low Mass Starsand Brown Dwarfs Stars which have just too little mass to become full stars are known as brown dwarfs. Although the boundary between what is a high-mass planet and what is a brown dwarf is fuzzy, if an object has more than 13 times Jupiterâ&#x20AC;&#x2122;s mass, it is called a brown dwarf, and if it has less mass, it is called a giant planet. Although some fusion can take place in a brown dwarf of fewer than 80 Jupiter masses, it is only fusion of deuterium and lithium-not enough to supply the brown dwarf with enough energy to counterract

Main Sequence The majority of a starâ&#x20AC;&#x2122;s lifetime is spent during the main sequence, although the duration of this stage varies dramatically, depending on the mass of the star; our Sun is in the main sequence at the moment. This stage is spent fusing hydrogen into helium in the core of the star. When the hydrogen supply begins to run out in the core, the core becomes unstable and contracts. The outer shell, which is still mostly hydrogen, starts to expand, cooling and glowing red [Figure 2].

High Mass Stars The most massive stars can have masses 100 times 52

Figure 1: Stellar Nursery in the Rosette Nebula [available from http:// www.nasa.gov/multimedia/imagegallery/image_feature_1653.html]

Young Scientists Journal | 2011 | Issue 10

gravity’s inward pressure. It is only at around 80 Jupiter masses that the brown dwarf has enough mass to fuse hydrogen, and be a fully-fledged star. Bizzarely, a 2006 article suggests that it may rain liquid iron on a brown dwarf [Figure 3].[1]

Red Supergiants Stars with more than 10 solar masses become red supergiants, after burning all their hydrogen,during the stage when they fuse helium into carbon. These supergiants have relatively cool surface temperatures (3500-4500 K) and radii between 200 and 800 times the Sun’s radius. As the helium turns into carbon, the core temperature increases, gravity continues to pull carbon atoms together and fusion creates all the elements up to iron. When the core contains mainly iron, fusion stops, as no energy is released by fusing iron nuclei together; indeed, energy must be put in to fuse iron.[2]

Figure 2: The Sun [available from http://www.nasa.gov/multimedia/ imagegallery/image_feature_21.html]

Supernovae Since energy is no longer being radiated from the core, the star collapses, causing the temperature to rise as the atoms are crushed together. The repulsive force between the nuclei overcomes gravity and the core recoils out in what we see as a supernova. As the shock wave hits material in the star’s outer layers the material is heated, fusing to form further elements. All heavy elements, including uranium and plutonium, are formed in supernovae. The material blasted into space by this explosion is known as the supernova remnant. This is the most common type of supernova (called a core-collapse supernova), but there are other, more exotic supernovae that may happen when extremely large stars collapse [Figure 4].

Figure 3: V838 Monocerotis (red supergiant) [available from http:// www.nasa.gov/multimedia/imagegallery/image_feature_784.html]

Black Hole If the remnant of a red supergiant core is more than three times the size of the Sun after a supernova, gravity overcomes the nuclear forces holding the protons and neutrons in the atoms apart. The core is then swallowed by its own gravity, eventually becoming a black hole. The black hole theoretically contains a ‘singularity’, a point of infinite density with a region of space around it, called an ‘event horizon’, beyond which it is impossible to escape from the black hole’s gravitational pull [Figure 5].

Neutron Star/Pulsar When a supernova explodes, if the remaining core is Young Scientists Journal | 2011 | Issue 10

Figure 4: Supernova 1994D in the outskirts of the galaxy NGC 4526 [available from http://en.wikipedia.org/wiki/File:SN1994D.jpg]

relatively small, the protons and neutrons combine to form neutrons. Neutron stars are very dense (1017Â times denser than water), having diameters of just 20 kilometers, yet masses three times that of the Sun [Figure 6].[3] Some neutron stars emit radio waves. These neutron stars are called pulsars. The waves seem to flash on and off, but this is only the case due to the beam of radio waves rotating around the poles of the stars, while the Earth remains relatively fixed relative to the rotating beams [Figure 7].[4]

Red Giant These are formed when low mass stars run out of hydrogen; they are very bright due to their large diameters, but they have lower surface temperatures

than the Sun (2300-3300 K). Like the red supergiants, they fuse helium into carbon in this phase. When all the helium in the core is used the core collapses again [Figure 8].[5]

Planetary Nebula These are the outer layers of a star that are lost when a star of around the Sunâ&#x20AC;&#x2122;s mass changes from a red giant to a white dwarf. The hot core of the star drives the outer half away in a stellar wind that lasts a thousand years. The remaining core is left, which heats the gases it has pushed away, causing them to glow [Figure 9].[6]

Blue/White Dwarf This is a very small, hot star with a similar mass to the Sun, but the same diameter as the Earth, that is

Figure 5: Simulated view of a black hole in front of the Large Magellanic cloud [available from http://en.wikipedia.org/wiki/File:BH_LMC.png]

Figure 6: The white dot in the centre of the image is the neutron star [available from http://www.nasa.gov/mission_pages/chandra/ multimedia/photos07-080.html]

Figure 7: Still from an animation of a pulsar [available from http:// www.nasa.gov/mission_pages/GLAST/multimedia/pulsar_stills.html]

Figure 8: The red giant Arcturus in comparison with The Sun [available from http://en.wikipedia.org/wiki/File:Arcturus-star.jpg]

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Figure 9: Helix nebula [available from http://www.nasa.gov/ multimedia/imagegallery/image_feature_77.html]

Figure 10: Sirius A (white dwarf) [available from http://www.nasa.gov/ multimedia/imagegallery/image_feature_468.html]

formed from the core of a red giant when it collapses. They are not very bright despite having temperatures of more than 8000째C. They cool and fade over billions of years [Figure 10].[3]

References

Black Dwarf

Black dwarfs are hypothetically what would remain once a white dwarf has cooled to around temperatures where they are not hot enough to emit light. However, none are expected to exist simply because the universe has not existed long enough to allow any white dwarfs to cool down enough to become black dwarfs.

4. 5. 6.

Jeanna B. Wild Weather: Iron Rain on Failed Stars. Space.Com, July 3, 2006. Available from: http://www.space.com/2576wild-weather-iron-rain-failed-stars.html. [Last accessed on 2011 Dec 30]. Available from: http://www.en.wikipedia.org/wiki/Red_ supergiant. [Last accessed on 2011 Dec 30]. Available from: http://www.telescope.org/pparc/res8.html. [Last accessed on 2011 Dec 30]. Available from: http://www.eclipse.net/~cmmiller/BH/blkns. html. [Last accessed on 2011 Dec 30] Available from: http://www.daviddarling.info/encyclopedia/R/ redgiant.html. [Last accessed on 2011 Dec 30] Available from: http://www.noao.edu/jacoby/. [Last accessed on 2011 Dec 30].

About the Author Cleodie Swire is doing Biology, Chemistry, Physics, Further Maths and Spanish at AS Level, and has already taken French. She is currently at The King's School, Canterbury, and hopes to do Medicine at University. She enjoys doing sport - especially hockey - and travelling.

Young Scientists Journal | 2011 | Issue 10

Origin of Life

The role of supernovae in the origins of life Ben Maybee Haybridge High School and Sixth Form, Worcestershire, UK. E-mail: maybeebw08@haybridge.worcs.sch.uk DOI: 10.4103/0974-6102.92199

This [Figure 1] is the Crab Nebula, the remnant of a supernova explosion that was observed in 1074 by Chinese astronomers. It is 6500 light years away from Earth. While being far away from the Earth, supernovae explosions are an essential part of the formation of life. This is because they have played a part in the formation and distribution of virtually every element that exists in the universe. Only hydrogen, some helium, and some lithium, formed 13.7 billion years ago in the Big Bang, were created independently of supernovae. So what are supernovae and how do they form large elements? The full answer is very complicated, but the simple one is through nuclear fusion.

Nuclear Fusion

Figure 1: Crab Nebula [Available from http://en.wikipedia.org/wiki/File: Crab_Nebula.jpg]

The sun is the closest star to Earth. All stars are driven through the process of nuclear fusion, a process by which atoms fuse together to produce new elements. An atom is mostly empty space; in the centre is the nucleus, which occupies a tiny proportion of the atom’s space yet constitutes 99.9% of its mass. Electrons occupy specific energy levels around the nucleus and determine the chemical properties of an element. However nuclear fusion, as its name suggests, is a nuclear, not chemical, reaction. The nucleus is composed of two different subatomic particles, the proton and the neutron. The number of protons in the nucleus of an atom is what defines what element the atom is. In nuclear fusion, the protons and neutrons of two different nuclei combine to form a single nucleus.[1]

Fusion, however, is not quite so simple, for while neutrons are electrically neutral, protons have a relative charge of +1. Electrostatic repulsion between protons is a barrier called the coulomb barrier, which protons must overcome in order to fuse. This is achieved by the strong nuclear force. The strong nuclear force is 1032 times stronger than gravity, while electromagnetism is only 1018 times stronger. However, we rarely feel the strength of the strong force, because it only acts over a distance of 1-1.5 × 10−15 m. If two particles come close enough together, the strong force will influence the particles and the electromagnetic Coulomb barrier is broken. But for this to take place, the particles require very high energies, in order to achieve the requisite velocity to come so close together.[2]

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Fusion in Stars In stars, there are two main different ‘cycles’ of nuclear fusion. These are called the proton-proton chain reaction (PP) and the Carbon-Nitrogen-Oxygen Cycle (CNO Cycle).[3] The PP chain is the reaction by which stars up to 1.3 times the mass of the sun fuse; its net results are the fusion of four protons to one alpha particle (a helium nucleus). Supernovae explosions can only result from stars that use the CNO Cycle[4] of fusion. The CNO cycle can only take place at temperatures of at least 13 × 106 K, hence its prominence in larger stars. In the CNO Cycle, four protons fuse, using carbon, nitrogen, and oxygen isotopes as a catalyst (the nuclei give fusion a platform on which to fuse and so lower the Coulomb barrier), to form an alpha particle, two positrons, and two electron neutrinos. The formation of another element by nuclear fusion is called nuclear synthesis. [5] Positrons are a form of antimatter (they are electrons with a positive charge), and so further energy is produced in the form of gamma rays when the positrons annihilate with electrons in the vicinity. The isotopes of carbon, nitrogen, and oxygen are essentially one single nucleus that is constantly recycled through the process. The nuclei either originate from the cosmic dust that the star formed from or a very small amount of fusing helium in a star’s core. The cycle is shown in Figure 2; the equations for the stages are: 612C+11H → 713N+γ+1.95 MeV 713N→613C+e++υe+2.22 MeV 613C+11H →714N+γ+7.54 MeV 714N+815O →713N+γ+7.35 MeV 715N+11H →612N+24He+4.96 MeV 815O→715N+e++υe+2.75 MeV The energy produced by the cycle’s fusion heats the star allowing fusion to carry on occurring until the star uses all of its hydrogen fuel. When a star has this equilibrium, it is said to be a ‘main sequence star’. All stars eventually reach the stage at which their hydrogen fuel runs out and their main sequence ends. Practically all stars have a brief stage at the end of their lives during which the helium that has been produced by hydrogen fusion begins to fuse, because the force of gravity (which is now larger than the radiation pressure) induces such immense pressures on the helium nuclei that three can fuse, by a process called triple alpha burning, into a carbon nucleus, or sometimes an oxygen nucleus. The increased fusion in the star’s core causes an Young Scientists Journal | 2011 | Issue 10

Figure 2: CNO Cycle [available from http://en.wikipedia.org/wiki/File: CNO_Cycle.svg]

Figure 3: S-process [available from http://en.wikipedia.org/wiki/File: S-process-elem-Ag-to-Sb.svg]

expansion into an Asymptotic Giant Branch star, virtually always a red giant. Red giants play a role in producing new elements. During their lives a slow neutron capture system called the S-process [Figure 3] increases the mass of the helium and carbon nuclei in the star until about half of the elements heavier than iron are produced; the other half are formed in the supernova itself by the R-process[6] (see end of section on supernovae). The nuclei of atoms can capture neutrons, increasing their mass whilst doing so. Neutrons in neutron-heavy nuclei undergo beta-minus decay, in which, through the weak force, a neutron decays into a proton, electron and an anti-neutrino. The S-process is the combination of these processes over thousands of years to form new elements. Normally the heavy elements are only formed in stars large enough to go supernova; they are only released into space during the actual explosion.

Supernovae There are two types of supernova; type I and type II.[7] 57

Ninety seven percent of all stars in the universe will collapse to form white dwarf stars at the end of their lives; most of the other 3% form type II supernova explosions.[8] As has been shown, a star’s helium will typically fuse to form carbon at the end of its life, and then collapse into a white dwarf. Whereas, if a star has a mass more than nine times than that of our sun, then when the star collapses after the helium fusion, the force of gravity is so immense that the pressures produced are high enough for the carbon produced by helium fusion to also fuse. Because of the reignited fusion, the radiation pressure is once again high enough to make the star expand, and so the cycle of expansion-contraction is repeated [Figure 4]. The main products of the carbon fusion are neon, sodium, and magnesium. When the gravitational contraction occurs the neon nuclei begin to fuse, so that the cycle is repeated until a nickel ion is formed.[9] The

cycle goes through this order [Figure 5], in which the element with an arrow coming from it is fusing. The specific nickel nucleus produced is that of a nickel-56 ion. The most important thing that now occurs in relation to the supernova explosion is that the nickel nucleus undergoes several beta decays to produce an iron-56 nucleus. Iron has the highest binding per nucleon of any element. The binding energy of an element is the energy required to break the nucleus’s components apart. Because of this, any fusion afterward is endothermic, not exothermic (i.e. takes in energy instead of giving it out). Therefore, an iron and nickel core accumulates in the centre of the star, with the other fusion products surrounding it in layers, so that the shown structure evolves. All of the elements lighter than nickel that exist in the universe, other than hydrogen, some helium and some lithium, were produced by this initial process. So how do the elements heavier than iron and nickel get formed? As further fusion is impossible, the answer is in the actual supernova explosion itself. The core at the center of the star is under immense pressure from gravity, and because no

Figure 4: Core collapse [available from http://en.wikipedia.org/wiki/ File: Core_collapse_scenario.png, edited by Ben Maybee]

Figure 5: Order through elements - Ben Maybee

Figure 6: Galaxy NGC 4526 [available from http://hubblesite.org/ gallery/album/pr1999019i/]

Figure 7: Star layers [available from http://en.wikipedia.org/wiki/File: Evolved_star_fusion_shells.svg]

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fusion is occurring, the star is only supported by the degeneracy pressure of electrons in the core’s atoms. By quantum mechanics, electrons occupy energy levels, or shells, around their central nucleus, and there are a finite number of spaces in each shell. Pauli’s Exclusion Principle prevents two electrons from occupying the same space in a shell. It is this quantum exclusion that is the degeneracy pressure. However, if the iron core accumulates to more than 1.44 solar masses, a point called the Chandrasekhar Limit, the degeneracy pressure is no longer enough to repel gravity and the core collapses. The electrons and protons of atoms, if given enough energy, can combine to form neutrons, in the process releasing neutrinos as well. This is what the collapse causes, and the energy involved is so high that the outer layers of the core travel at 70000 kms−1, almost a quarter of the speed of light. Because neutrinos rarely interact with matter they escape from the collapse, and in doing so, remove energy and further accelerate the collapse. Eventually, contraction is halted by neutron interactions, mediated by the strong force. Because of the incredibly large gravitational energy that was held by the collapsing material, the collapsing matter rebounds, producing a huge shock wave that travels through the star. The newly produced neutron core has a temperature of about one hundred billion Kelvin at this point. Much of the excess thermal energy is lost by the release of more neutrinos, resulting in a ten second neutrino burst. These neutrinos carry a massive 1046 Joules of energy, but 1044 J is reabsorbed by the stalled shock wave, producing a massive explosion. This reinvigoration of the shock by interaction with the neutrino burst blasts away the layers that surrounded the core, leaving behind a neutron star, or if the star was more than 20 times larger than the sun, a black hole. The supernovae release so much energy and radiation that they can appear brighter than whole galaxies. Figure 6, taken from the Hubble Space Telescope demonstrates this; the bright dot in the left corner is one single supernova, 1994D in Galaxy NGC 4526. During the explosion, about half of all of the other elements heavier than nickel are formed, by a process called the R-process. The R-process is caused by the massive amount of neutrons that exist in a supernova after the core collapses. Because of this, in the explosion, there is an incredibly high ‘neutron flux’, or the amount of neutrons that pass through an area per second increases; in this case, it is about 1 × 1022 per cm2 per second. This high Young Scientists Journal | 2011 | Issue 10

neutron flux is combined with a very high temperature. The R-process is dependent on exactly the same processes as the S-process, neutron capture and beta decay. However, due to the high temperature and neutron flux in a supernova, the R-process is much, much quicker and the rate of neutron capture is higher than the rate of beta decay. Because of this, nuclei produced before the explosion rapidly capture neutrons until they reach something called the neutron drip line. At this point, the nuclei are so neutron-heavy they must undergo beta decay before more neutrons can be captured. Both the atomic number and atomic mass of the nuclei increase very rapidly, as protons are being formed by alpha decay and the neutrons are then captured. This process forms very high-mass radioactive elements; the maximum possible mass is thought to be about 270 nucleons. Most of the high-mass elements then decay into heavy, but stable, neutron-rich nuclei. This process all happens very rapidly during the explosion, which blasts the nuclei into interstellar space along with those formed by the S-process in the original red dwarf.

Why are Supernovae Important for Life? It is at this point that we should now consider the initial title: Why are supernovae important to life? The simple answer is that other than hydrogen, some helium, and some lithium (which were formed in the Big Bang); every element in the universe was produced by a star at the end of its life and expelled into space by a supernova explosion. Supernovae are thought to be solely responsible for the formation of half of all the elements heavier than iron, and also the formation of virtually every element in the mass range between helium and iron. Through all of this nucleosynthesis, supernovae are what produce the elements that not only are fundamental for all known life forms, such as carbon, oxygen, and nitrogen, but also the elements that form the planets on which life evolves and develops. Supernovae are responsible for the dispersion of heavy elements, produced by both the R and S-processes, all around the universe. Without the formation of an iron and nickel core [Figure 7] at the very end of a massive star’s life, the core of our own planet could not possibly have formed. Without this core, our planet [Figure 8] would never have been able to form from the dust cloud that existed in the early years of our solar system. In fact, without the nucleosynthesis inside supernovae, explosions and the conditions that existed just before, as well as the dispersion of the heavy elements produced by red 59

all made of stardust”.

References 1. 2. 3.

4. 5. Figure 8: The Earth [available from http://en.wikipedia.org/wiki/ File:The_Earth_seen_from_Apollo_17.jpg]

6. 7.

giants, none of the planets, asteroids, comets, and heavy mass objects that we observe in the universe would exist. The universe would be completely lifeless, containing just stars and giant clouds of gas. Then, in short, as the old saying goes: “We are

8. 9.

Nuclear Fusion. Available from: http://www.atomicarchive.com/ Fusion/Fusion1.shtml [Last cited on 2011 25 Jan]. Jim al-Kahili, Quantum: A Guide for the Perplexed (Phoenix, 2004). CNO Hydrogen Fusion Simulator. Available from: http://www. astrophysicsspectator.com/topics/stars/FusionHydrogenCNOSim. html [Last cited on 2011 25 Jan]. The CNO Cycle. Available from: http://en.wikipedia.org/wiki/ CNO_cycle [Last cited on 2011 25 Jan]. Nuclear Synthesis. Available from: http://www.hyperphysics. phyastr.gsu.edu/hbase/astro/nucsyn.html#c1 [Last cited on 2011 25 Jan]. R-process. Available from: http://www.encyclopedia.com/ topic/r-process.aspx [Last cited on 2011 25 Jan]. Type II Supernova. Available from: http://www.en.wikipedia. org/wiki/Type_II_supernova [Last cited on 2011 25 Jan]. What are Supernovae? Available from: http://www.spider.ipac. caltech.edu/staff/vandyk/supernova.html [Last cited on 2011]. Supernovae: An Overview. Available from: http://www. astrophysicsspectator.com/topics/supernovae/ [Last cited on 2011 25 Jan].

About the Author Ben Maybee is a 15 year old student at Haybridge High School and Sixth Form, Worcestershire, UK. He finds physics beyond the standard curriculum really fascinating because of the challenging ideas and way of understanding the universe that it presents us, and he thus has a particular interest in quantum and particle physics. Nuclear fusion and how it operates in stars is another area that intrigues Ben, because it incorporates many different fields of physics and it is the fundamental process by which most of the universe was built.

Announcement

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Young Scientists Journal | 2011 | Issue 10

Origin of Life

The Endosymbiotic Theory Cleodie Swire The King's School, Canterbury, E-mail: 07ccs@kings-school.co.uk DOI: 10.4103/0974-6102.92200

Definitions Prokaryote – Organism with cells without a true nucleus or other membrane-bound organelles Eukaryote – Organism whose cell(s) contain(s) a distinct, membrane-bound nucleus Autotroph – An organism that can make its own food Heterotroph – An organism that must obtain readymade food Endocytosis – A process in which a cell takes in materials by engulfing them and fusing them with its membrane, as shown in Figure 1

Carbon dioxide + Water (with sunlight and chlorophyll) → Carbohydrate + Oxygen Figure 2 shows that mitochondria and chloroplasts are very similar to prokaryotic cells; these observations lead to The Endosymbiotic Theory.

Theory Researchers comparing the structures of prokaryotes and cell organelles, as shown in Figure 2, came to the conclusion that organelles such as mitochondria and chloroplasts had originally been bacteria that were taken into larger bacteria by endocytosis and not digested. The cells would have had a mutually beneficial (symbiotic) relationship. The ingested cells developed

Aerobic – Organism that requires oxygen for survival Anaerobic – Organism that can function without oxygen Symbiosis – Two different organisms benefit from living and working together Endosymbiosis – One organism lives inside another Mitochondrion – Organelle where aerobic respiration occurs within the cell Carbohydrate + Oxygen → Carbon dioxide + Water + Energy Chloroplast – Organelle where photosynthesis occurs in plant cells Young Scientists Journal | 2011 | Issue 10

Figure 1: A diagram showing endocytosis [available from http:// en.wikipedia.org/wiki/File: Average_prokaryote_cell-_en.svg]

Cell type DNA

Eukaryote Organized into chromosomes Ribosomes 80S Size/microns 50-500 Cell nucleus? Yes Membrane-bound organelles? Yes Replication Mitosis Number of cells One or more Example/image Animal cell

[available from http:// en.wikipedia.org/wiki/File: Pinocytosis.svg]

Prokaryote Single loop 70S 1-10 No No Binary fission Usually one Bacteria

Mitochondria Single loop

Chloroplasts Single loop

70S 1-10 No No Binary fission

[available from http:// en.wikipedia.org/wiki/File: Animal_cell_structure_ en.svg]

[available from http:// en.wikipedia.org/wiki/File: Animal_mitochondrion_ diagram_en_(edit).svg]

[available from http:// en.wikipedia.org/wiki/File: Animal_cell_structure_ en.svg]

Figure 2: A table comparing various characteristics of different cells and cell types

into organelles, such as mitochondria and chloroplasts, which now cannot live outside the host cell.

Mitochondria Aerobic bacteria were taken in by anaerobic bacteria. The enveloped bacteria would have used the oxygen from the air (which was useless to its host) to provide far more adenosine triphosphate (ATP) (useful energy) than the host could produce on its own, while the host cell would provide materials to respire, protection, and a steady environment.

Chloroplasts Autotrophic photosynthetic bacteria cells were taken in by the heterotrophic prokaryote cells. The ingested cell would continue to provide glucose and oxygen (which could be used by the mitochondria as endocytosis of the photosynthetic prokaryote occurred after the endocytosis of aerobic cells) by photosynthesis. The host cell would provide carbon dioxide and nitrogen for the engulfed cell, as well as protecting it.

to the 80S ribosomes found in eukaryotic cells. These cells all divide by binary fission, as shown in Figure 3. DNA The organelles have their own DNA, separate to the DNA found in the nucleus of the cell, which they use to produce enzymes and proteins to aid their function. This was predicted by the researchers, and was later proved to be true for mitochondria and chloroplasts. All of these likenesses suggest that mitochondria and chloroplasts developed from prokaryotes. Double outer membranes Mitochondrion and chloroplasts have double outer membranes â&#x20AC;&#x201C; the inner layer came from the engulfed cell and the outer membrane from the host cell during endocytosis.

Proof

Replication Mitochondrion and chloroplasts can only arise from pre-existing organelles â&#x20AC;&#x201C; the DNA that codes for them is not found in the nucleus of the cell, but in naked loops of DNA within the organelles themselves. This suggests that these organelles were originally separate cells that needed to replicate themselves.

Similarities to bacteria Figure 2 shows that mitochondria and chloroplasts have many similarities to prokaryotic bacteria. They are of a similar size and have 70S ribosomes, as opposed

Fossil record [Figure 4] Fossil evidence shows that bacteria were present 3.8 billion years ago, when there was no oxygen in the atmosphere and all organisms were anaerobic.

Over time, both cells lost their ability to survive without each other.

Young Scientists Journal | 2011 | Issue 10

Photosynthetic bacteria appeared about 3.2 billion years ago, producing oxygen. As the oxygen levels increased, the anaerobic organisms began to die out as oxygen is toxic to most cells (even ours!). Organisms that could respire aerobically developed about 2.5 billion years ago. This evidence suggests that the ‘ancestors’ to the mitochondria and chloroplasts developed outside the cell, and later merged with other larger prokaryotes, leading to the development of eukaryotes. Uses The discoveries regarding the origins of the mitochondria and chloroplasts have led to several scientific applications.

History of Evolution The DNA found in mitochondria (mtDNA) is passed

directly from mother to child, and changes much more slowly than other types of DNA, providing information about evolutionary history. This can be used to determine how closely related two species are to one another and migration patterns as shown in Figure 5.

Astrobiology Organisms called archaebacteria, which live in the most extreme habitats on Earth, have been studied as they are the organism believed to be most like the bacteria that inhabited the Earth billions of years ago. They now inhabit salt ponds and boiling hot springs. As they live in places previously assumed to be unsuitable for life, they are being studied as they may provide clues about extra-terrestrial life. There has been some research done suggesting that the archaebacteria could survive space travel by meteorite, so there is potential for life on other planets.

Researcher The Endosymbiotic Theory of eukaryote evolution was first suggested by Dr. Lynn Margulis [Figure 6] in the 1960s, and officially in her book, ‘Symbiosis in Cell Evolution' in 1981. Her ideas were initially ridiculed by her fellow biologists, but through research and persistence her theory was eventually accepted and is now regarded as the most credible explanation of eukaryote evolution. She is best known for her theory of symbiogenesis,

Figure 3: A diagram showing binary fission of a prokaryotic cell [available from http://en.wikipedia.org/wiki/File: Binary_fission.svg]

Event Origin of the Earth Prokaryote bacteria dominate Oxygen starts to accumulate in the atmosphere Eukaryotes appear Cambrian explosion of multicellular eukaryote organisms

Years ago 4.5 billion 3.5 billion 2.5 billion 1.5 billion 0.5 billion

Figure 4: Timeline of events affecting The Endosymbiotic Theory

Figure 5: A graph showing human migration patterns, created by studying mtDNA. The letters denote the different groups of mtDNA [available from http://en.wikipedia.org/wiki/File: Migration_map4.png]

Young Scientists Journal | 2011 | Issue 10

Figure 6: Dr. Lynn Margulis [available from http://en.wikipedia.org/ wiki/File: Lynn_Margulis.jpg]

which expanded on the aspect of The Endosymbiotic Theory in which the relationship between the prokaryotic cells becomes so strong that the two grew to be dependent on one another. Margulis suggested that this process may have also occurred

at other times during evolution. This theory challenges Darwinâ&#x20AC;&#x2122;s idea that mutations occur by genes being passed down from parents to offspring, rather than the genetic material of unrelated organisms being brought together.

About the Author Cleodie Swire is doing Biology, Chemistry, Physics, Further Maths and Spanish at AS Level, and has already taken French. She is currently at The King's School Canterbury, and hopes to do Medicine at University. She enjoys doing sport - especially hockey - and travelling.

Lynn Margulis (born on the 5th March1938, died on the 22nd November 2011), who was mentioned in the article, sadly died at home after a stroke, aged 73. Many tributes can be for her glorious scientific life can be seen in various obituaries (see the Daily Telegraph Newspaper - http://www.telegraph.co.uk/news/obituaries/ science-obituaries/8954456/Lynn-Margulis. html, the New York Times News Paper - http:// www.nytimes.com/2011/11/25/science/lynnmargulis-trailblazing-theorist-on-evolutiondies-at-73, the Nature 22/29 December 2011 issue - http://www.nature.com/nature/journal/ v480/n7378/full/480458a.html, Scientific American - http://blogs.scientificamerican. com/cross-check/2011/11/24/r-i-p-lynnmargulis-biological-rebel/ and Discovery News - http://news.discovery.com/earth/lynnmargulis-pioneer-of-evolutionary-biology-diesat-73-111124.html). 64

Dr. Lynn Margulis at work (Photo: Lynn Margulis at work in a greenhouse, circa 1990. (Nancy R. Schiff/Getty Images))

Young Scientists Journal | 2011 | Issue 10

Origin of Life

A review of 10 of the best Origin of Life books Fiona Jenkinson The King’s School, Canterbury, E-mail: 08flvj@kings-school.co.uk DOI: 10.4103/0974-6102.92201

As soon as man gained consciousness, it is almost certain we began to wonder where we and everything else came from. For a few thousand years now, this has been a topic for which religion has always found some sort of explanation, and, for many thousands of years, this seemed satisfactory. In the most recent centuries, science has undergone a revolution and it has been possible to date, trace, and even begin to envisage our past like never before, forever getting closer to the origin of life itself. Of course, this had led to controversy, exaggeration and plain myth in many different areas. Since the origin of life is a topic which still mystifies everyone, it is best to be able to evaluate the many theories that stand today for oneself. So here is a list of books which feature the theme of our origins: The Origin of Life – by Paul Davies. It is simple and informative, but broad - a great start to thinking about how life ended up, was created or appeared on earth. It allows the reader to create their own hypothesis as to how it all began before presenting the present-day ideas using evidence from a range of sciences. Seven Clues to the Origin of Life – a scientific detective story by A.G. Cairns-Smith is an enjoyable read, explaining the different pieces of biological evidence with regards to the origins of life with a lot of inspiration from Sherlock Holmes. Although some interpretation of primitive Earth’s atmosphere has changed since this was written, it gives you a complete sensation of the biological enigma – where Young Scientists Journal | 2011 | Issue 10

did this life come from? Somewhat the extreme opposite to a murder mystery. Revolutions that Made the Earth – by Tim Lenton and Andrew Watson is a detailed and vivid account of the creation of the Earth and life, according to our present day scientific knowledge. An interesting read, which links earth-changing events to the origin of life, to show how the basic necessities for life, which we take for granted, all ended up on our small blue planet. Rare Earth: Why Complex Life is Uncommon in the Universe - by Peter Ward is easily comprehensible and describes effectively how the conditions for complex life that are found on Earth are at least very scarce in the universe. It gives balanced accounts on most information and considers the frequency of simple life forms in the universe, arguing that this may not at all be a rare occurrence. The Ancestor's Tale: A Pilgrimage to the Dawn of Life - by Richard Dawkins. Starting with the present day Homo sapiens and ending with the creation of RNA, each chapter traces back the evolutionary tree for each species that produced mankind. This looks at the origin of life from an evolution perspective. The Seven Daughters of Eve: the astonishing story that reveals how each of us can trace our genetic ancestors by Brian Sykes. This book, focusing on human origins, begins with the gruesome discovery of a frozen body in the Alps and ends by finding that 65

almost all Europeans are related to one of seven women. It is an intriguing story and you soon find yourself well â&#x20AC;&#x153;informed of what has gone before and ignorant of what [lies] aheadâ&#x20AC;?, as was the author, on his own autobiographical adventure. It is written with 66

humour and in itself can be read for plain leisure. Although it must be well noted that the depictions of the European ancestors are fictional, you are left with a true appreciation of genetic inheritance, time and the lives of our ancestors. Young Scientists Journal | 2011 | Issue 10

Are we alone? – by Gloria Skurzynski explores the possibility of extra-terrestrial life: as a research team in the Brazilian jungle await radio signals from other life in the universe, some are observing moons and planets which potentially have the ideal conditions for life to exist and others contemplate the possibility that the origin of life may be from elsewhere – that we may be the aliens. Genesis: The Scientific Quest for Life's Origins - by Robert M. Hazen is quite a personal account in which he considers the value of many of the present day theories, such as primordial soup and the origin of life, from thermal vents and highlights others as plain myths. It mostly considers how the chemical processes and molecules necessary for life came about. What is life? The Physical Aspect of the Living Cell - by Erwin Schrödinger. Although written before the discovery of DNA, this book presents the idea of life from the point of view of a physicist. In broad terms, it implies how it is necessary to abandon ideas of

interactions on the quantum scale, when dealing with life on its similarly complex macro scale. The Origins of Life - Melvyn Bragg and guests (Richard Dawkins, Richard Corfield, and Linda Partridge) discuss when and how life on earth originated. For those who prefer listening to reading, this 45 minute, informative BBC radio four program covers many views on the origin of life including the definition of life itself. It is easy to listen to and explains almost everything from basic to complex ideas on this topic. The broadcast is found on this link: http:// www.bbc.co.uk/iplayer/console/p004y29f Bibliography – all images sourced from www.google. co.uk/books, www.amazon.com and http://www.bbc. co.uk/iplayer/console/p004y29f

About the Author Fiona Jenkinson is 16 years old and goes to The King's School Canterbury where she is currently studying for her AS Levels. She is studying Biology, Chemistry, Physics and Maths. In her free time she enjoys art, music, photography and reading. She is unsure of what she wants to do in the future. Young Scientists Journal | 2011 | Issue 10

Interview

Interview with Dr. Luis Delaye Liliana Corona Martínez Autonomous University of Queretaro, Mexico, E-mail: lilianabroken@hotmail.com

ABSTRACT

Dr. Luis Delaye works at the Research and Advanced Studies Centre of the National Polytechnic Institute of Mexico (CINVESTAV). His work takes place in the Evolutionary Genomics laboratory within the department of Genetic Engineering, and his area of research is the origin and evolution of new genes, the evolution of reduced genomes, and horizontal gene transfer. In his early years, his interests were focused on the origin of organisms, and as a result, he has been devoted to the subject of evolution since his undergraduate studies in Biology at the National Autonomous University of Mexico (UNAM). In 2009, Dr. Delaye completed his postdoctoral studies in Valencia, Spain.

Liliana Corona (LC): Hello, today we are with Dr. Luis Delaye,and we would like to know a bit more about his work as a researcher of evolution at CINVESTAV. Dr. Luis Delaye (LD): Hello, thank you very much, it is a great pleasure to be here. LC: Let’s start with the essential, how would you define ‘evolution’? LD: Well, evolution is a fascinating process and in my opinion it could be defined on three levels corresponding to the way in which we study it: The first is microevolution, which refers to the change of allele frequencies in populations, where mutations play a fundamental role in the change between generations. The intermediate level, where we study the speciation process, is the part that connects macroevolution with microevolution, and involves the mechanisms,by which new species arise, the role of natural selection and endosymbiosis. The third is macroevolution, by which large groups 68

of living things arise, such as molluscs, plants, eukaryotes, and etc. It is also responsible for order within the ‘evolutionary tree’ structure. This level requires large-scale study. LC: Why is it important to study evolution? LD: Well, it has a fundamental importance – first of all because nothing in biology makes sense or is logical without the light of evolutionary theory – evolution provides coherence, and most importantly, allows us to attempt to understand what the origin of life was. Secondly, evolutionary theory is useful for practical applications. It was Pasteur who said: “There are no such things as applied sciences, only applications of science”.The scientific study of living beings allows us to learn how microorganisms adopt new mechanisms, for example resistance to antibiotics, which is particularly relevant when it comes to fighting viruses, where it is necessary to investigate their mechanisms of defense. Artificial selection is also important in the improvement of agricultural produce. Young Scientists Journal | 2011 | Issue 10

LC: Why did you decide to work in this area? What was your motivation? LD: Since I first began studying, the most important question I had was how life originated. This led me to venture into the laboratory of Dr. Antonio Lazcano at UNAM, which was devoted to the study of the origin of life. In that lab, they studied a number of evolutionary processes that explain the characteristics of microorganisms and that was fantastic. LC: What have been your favourite research projects in your career so far? LD: Well, one of them was my thesis for my degree, since to explain the main subject it relied on two theories – Horowitz’s theory and the Patchwork theory – and I found all this material fascinating. I have also worked on a project on the evolution of polymerases, and although it was not published, I enjoyed it all the same. When I worked on the reconstruction of SOPE genome, a really interesting apparent product of endosymbiosis, I was fascinated because I really enjoyed discovering the origin of new genes. LC: What has been the most interesting result from your research? LD: It was when I worked with the issue of the origin of new genes, because when I made my hypothesis for the project, my prediction was correct. I had originally developed a theory; but a few years ago,it was tested experimentally in the U.S. and the result was as I had predicted. This was very exciting for me. Also during my PhD, I worked on a project about endosymbiosis in which I began to study genomes, and it was quite challenging for me to assemble something so complex (which, by the way, is still incomplete). I was fascinated by collecting new and interesting data about a biological system.

was difficult for me because during my undergraduate studies, I did not see much Math, and when I began looking at the theory of evolution, there was a lot of Math involved. It gets even more complicated with mathematical modeling of things such as the inference of past processes, which allows you to connect events and find out how they happened. Math is also vital in order to make correct predictions. LC: What tool do you use to study evolution? LD: Well, it depends which area you study – there are all sorts of areas that you could focus on in evolution, from archaeology to ecology, but in my case, I use computers. They are a basic tool, but they are essential for the creation of databases. LC: And speaking of computers, what is the role of bioinformatics in the study of evolution? LD: Critical, because it provides the means to answer the questions we have, for example BLAST is a program that helps us to find homologous genes for evolutionary analysis. We also have tools that allow us to do phylogenetic analysis to study protein structures or gene databases. There are also programming languages like Python, which are built to carry out programs that simulate the evolutionary processes that we are interested in. LC: What message would you give to young people who want to work in this area? LD: To trust their intuition and skills; evolution is the most fascinating branch of biology, and there is now almost no field of biological research that doesn’t

LC: What projects are you currently working on? LD: I am studying a series of overlapping genes that have demonstrated their existence experimentally, and by estimating rates of evolution, I am trying to infer whether there is a related feature, and also evidence of natural selection in viral proteins. As well as this, I am creating a project with the aim of constructing a database in order to study the comparative biology of reduced genomes. LC: What obstacles do you face? What is the biggest challenge in the study of evolution? LD: Well, in my case, it has been the mathematics. It Young Scientists Journal | 2011 | Issue 10

Dr. Luis Delaye Photo courtesy of Liliana Corona Martínez

require a tool or knowledge provided by evolutionary biology. LC: Finally, do you have any advice for readers? LD: I can recommend reading some authors, such as Darwin of course, but also Lynn Margulis, Stephen Jay Gould, Richard Dawkins, Ernst Mayr to start with.

Also, if you want to work in bioinformatics, I would advise studying biology first and then studying computer science afterwards. LC: Dr. Delaye thank you very much for this valuable information about your training and work as a researcher in the very interesting topic that is evolution.

About the Author Liliana Corona MartĂnez is currently studying at the University of Queretaro in Mexico.

Information for Teachers 1. Have you seen examples of STEM work in schools which deserves to be published? 2. Are there projects or coursework out there which will otherwise lie forgotten on a shelf or USB memory stick? 3. Would you like to encourage a student (or group) to consider publishing it in a science journal for others to read and for posterity? (â&#x20AC;Śbeing a published author looks great on their CV!) The Young Scientists Journal allows students to enter into the world of scientific publishing and journalism by providing them with the opportunity to research and write their own articles. The articles will then be processed by student Editors and an International Advisory Board before being sent to the publishers where they will be made into official articles, each with a unique code. Many of our authors have conducted scientific research for coursework, competitions, holiday placements or projects. We are also keen to receive shorter, review articles, and creative material such as videos or cartoons. There is also the opportunity for them to discuss scientific issues with students between the ages of 12 and 20 from all over the world. On a weekly basis, the latest international science news is summarised on the website, providing a simple resource for aspiring scientists. If you know a student who would be interested in getting more involved, and helping to run the journal, we are actively recruiting students at the moment to our Young Scientists team in many roles including editing articles, managing the website, graphic designing and helping with publicity. You may be interested in becoming an ambassador for Young Scientists by joining our International Advisory Board. If so, please send an email to Christina Astin, cma@kings-school.co.uk 70

Young Scientists Journal | 2011 | Issue 10

Interview

Interview with Dr. Gabriela Olmedo Liliana Corona Martínez University of Queretaro, Mexico, E-mail: lilianabroken@hotmail.com

ABSTRACT

Dr. Gabriela Olmedo works for the Center for Research and Advanced Studies of National Polytechnic Institute (CINVESTAV) Irapuato, Guanajuato where she is the chief of the Department of Genetic Engineering. She is an expert microbiologist, with her research focusing on RNA metabolism and bacterial comparative genomics. She is currently working on a research project studying the biodiversity of Cuatro Cienegas, Coahuila, Mexico. This place is known for its 300 lakes that have a similar trophic chain to the Jurassic Period. She received her PhD at the University of Pennsylvania, Philadelphia.

Liliana Corona (LC): Today we are with Dr. Gabriela Olmedo (GO) to find out about her work as a research scientist. LC: Well, let’s start: How could you define ‘evolution’? GO: I can describe it as a number of changes in genetic material that result in alterations in the

Dr. Gabriela Olmedo [available from 1. http://www.ira.cinvestav.mx/ Investigaci%C3%B3n/DepartamentodeIngenier%C3%ADaGen%C3%A9 tica/ProfesoresInvestigadores/DraOlmedoAlvarezGabriela/tabid/114/ language/es-MX/Default.aspx]

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morphology and metabolism of organisms over many years, resulting in the diversity that we now see. LC: Why has Cuatro Cienegas (CC) become a place to study evolution? GO: CC has a very special microbial population and the study of bacteria is a simple model that allows us to understand how changes occur in the genetic material in a short time. We analyze changes in the genomes at a molecular level, and study their relationship to specific genes that contribute to metabolic characteristics that we can monitor. It also demonstrates how the environment affects organisms to generate diversity. LC: What makes CC so special? GO: The geological origin of the lakes at CC makes it a very special place. Also, the isolation has helped it remain untainted and has kept the organisms that live there cut off which makes it an ideal system to study. Each of the lakes at CC has different organisms and it is very interesting to compare the bacteria between them. We also compare them with bacteria that live outside of CC, making it possible to ask questions about the biology and evolutionary 71

relationships of bacteria. These can be answered using microbiological and genomic tools. LC: Which have been the most important discoveries in CC? GO: For over 10 years, researchers from different countries have expressed interest in studying the valley of CC because they know the diversity and large number of endemic organisms that it has. The best known are the fish and snails studied by a group led by Dr. Minkley. Dr. Valeria Souza was a pioneer in microbiology research, and she found that many bacteria that live in the lakes have genetic characteristics indicative of a marine origin. Another feature of the lakes is the limited nutrients, especially phosphorus; it has been interesting trying to understand what mechanisms the bacteria use to survive there. LC: Have any microorganisms with special characteristics been found in these pounds? GO: Dr. Souzaâ&#x20AC;&#x2122;s group isolated heat-resistant bacteria of the genus Bacillus and then sequenced their DNA to see if this would reveal what metabolic characteristics made it possible for the bacteria to survive in a lake with such low phosphorus levels. Bacillus coahuilensis was the strain chosen for sequencing. One of the salient features that we found in its genome was the presence of two genes that give this bacterium the ability to synthesise sulpholipids. Most living organismsâ&#x20AC;&#x2122; membranes have a high content of phospholipids, so this is an important adaptation in an environment absent of phosphorus. The presence of the sulpholipids was later proved biochemically. The genes that give this property are very similar to the genes in cyanobacteria, so we speculate that they were acquired by horizontal transfer of genetic material from cyanobacteria (with which Bacillus coexists). LC: Why has this microorganism been able to survive? GO: Another feature of B. coahuilensis that has allowed it to survive at CC in the lake Churince is its ability to absorb nutrients using several transport proteins in the membrane. Therefore, despite

lacking several metabolic pathways and the ability to synthesize eight amino acids, it is able to obtain these nutrients from other bacteria. LC: What expectations do you have about the future of this project? GO: We have a large collection of bacteria of the genus Bacillus and we are planning to study them with genomic tools to understand their metabolism and ecology. A challenge for us is to analyze these bacteria and bacterial communities to learn about the exchange of genes, the metabolic characteristics which allow them to live in a community and other adaptations that allow them to grow and survive in this environment. LC: What message would you give to young people thinking about a future in the study of evolution? GO: Learning about the evolutionary process is fascinating, with new methods of DNA sequencing and analysis giving us the possibility to make comparisons at different levels and to explore how the microorganisms manage to be so diverse and to adapt to countless extreme environments. These range from those deficient in nutrients to those contaminated with metals to those with very high temperatures. It is interesting to find out about how there is a continuous exchange of genetic material in bacterial populations through plasmids and bacteriophages (viruses that infect bacteria). This DNA is a shared asset that belongs to no individual bacterium and is continuously exchanged. Therefore, bacteria have to use mechanisms to defend against the invasion of DNA and maintain a balance between defending their genetic identity and exploiting the adaptive opportunities that the DNA may bring. LC: Finally, do you have any advice to readers? GO: If anyone is thinking of engaging in research you must expect a fascinating world where there are surprises every day; science itself evolves continuously. It takes effort and perseverance to keep pace and not fall behind in research.

About the Author Liliana Corona MartĂnez is currently studying at the University of Queretaro in Mexico.

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Review Article

A dual nature of light Maciej Bąk Jagiellonian University, E-mail: bakmaciej@wp.pl DOI: 10.4103/0974-6102.92204

Have You ever Wondered Exactly What Light is? No cheating. Have you ever looked at a beam of light and asked yourself that question? Some say it is nothing more than a wave, while others insist that light consists of lots of tiny elementary particles. However, is it possible that both of these statements prove to be true? A whole new branch of science, called quantum mechanics, deals with such issues and its latest research may shed some light on it. In physical terminology, a quantum is the minimum unit of any entity – in this case a quantum of light would be called a photon. So, are the photons able to behave like particles and still maintain their wave properties? For a better understanding of this case, try to imagine that dualism before moving on.

Particles of Light Nowadays, most people would describe light as a wave, probably because it seems more intuitive. However, do you know that many great scientists of earlier centuries would not agree with that statement? One of the most famous physicists - Isaac Newton - who is well known for his description of universal gravitation and the three laws of motion also dealt with the issue of light. He claimed that it is no more than a cluster of unimaginably small particles, emitting energy. A simple experiment can prove his theory. The light (more precisely – the photons) falling on the metal plate releases electrons. These can then be captured Young Scientists Journal | 2011 | Issue 10

Figure 1: The photoelectric effect

by the second plate, which means that electric current, that can be measured, flows between these two objects. This phenomenon is called the photoelectric effect1 [Figure 1] and is widely used in modern devices, such as photocells, solar batteries, digital cameras, etc. Light absorbed by these devices is used to produce electricity and generate an electrical charge. Of course Newton did not know any of this, or even the definition of an electron, which was discovered in 1897 – more than a hundred years after his death.

A Diffracted Wave From the time of Newton’s postulates, people The person who discovered the photoelectric effect was none other than Albert Einstein. It was for this experiment that he gained the Nobel Prize in 1905 not for, what many believe, General relativity (which describes the influence of gravity on space-time) or Special relativity (which explains the behavior of physical bodies with a speed close to speed of light in vacuum). 1

thought light actually consisted of small particles. However, a breakthrough came in the early 19th century. An English polymath, Thomas Young, made a revolutionary discovery. He made an experiment, later named The Double-slit Experiment, which proved that light has the structure of a wave. Young used a source of a coherent light (waves in phase with each other) to illuminate a screen. Between that he placed a thin plate with two parallel slits cut into it. The wave nature of light causes its waves passing through both slits to interfere, creating an interference pattern of bright and dark bands on the screen.2 This is very similar to waves which appear on water when one throws a rock. Similarly, if one throws two rocks, waves will interfere with each other and create a characteristic wave system.

The Unification of Theories Since photons have shown they can behave both as particles and as waves, scientists had no choice but to agree on the wave–particle duality of light. The most common argument for its dual nature is Compton Scattering [Figure 2]. Put simply, it is all about the dispersal of a short light wave into free electrons and a longer wave.3 Now it is also known that the shorter the wavelength is, the more energy is carried by the beam. In fact, colours of visible light are nothing other than the effect of different energy values – for example: blue light (short wavelength, In this experiment Young also exploited the phenomenon of wave diffraction. This means all waves bend around small obstacles, slightly changing the direction of propagation. 3 In fact, a visible light beam is an electromagnetic wave of a specific length, possible to see with the naked eye. Shorter waves of the same structure (also comprised of photons) are, for example, X-rays or infrared. Compton scattering concerns X-rays of high frequency and electrons. An electromagnetic wave scatters on free particles, creating a shorter wave (less energetic) and knocking out the electron (which just gained the difference of the energies) in a specific direction. Photons are able to knock out electrons only because of their particle properties and we are able to measure their energy only by registering the frequency of the light wave. Compton scattering is widely used in technology and medicine, especially in radiology. 2

Figure 2: The Compton scattering

high frequency) carries much more energy than a beam of red light (relatively long wavelength and, because the speed of light is always the same, lower frequency). Due to the dualistic nature of light, we may also say that its “red photon” has less energy than a “blue one”. Not many years ago, more scientific research was carried out at Harvard University in the USA. Researchers managed to illuminate a container with an ultra-cold cloud of sodium atoms. When the beam was switched off, the gas mixture that recorded the properties of trapped light was pumped into the second container and exposed to a laser beam. Seconds later, the container glowed. Scientists say that this process may be used during manipulation of information transmission in future quantum computers, which would have a much greater computing power than conventional devices. Some say that the ability to record the properties of a wave and then regain it in other place may be the very first step to teleportation. In summary, the photon’s action can actually depend on the situation- it can behave as if it were a particle and as if it were a wave. According to quantum mechanics, the whole matter is characterized by this dualism. Each particle and even each object can be attributed to its characteristic wave function, resulting from the probabilistic nature of matter. On the other hand, each wave interaction can be described in terms of particles.

About the Author Maciek Bąk is a Polish 19 year old and currently studies Biotechnology at Jagiellonian University. He is very keen on Genetics, Immunology and Quantum Mechanics. He went to private high school in Kielce.

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Review Article

Melanomas and their effect on the grey horse Katherine Burden The King's School, Canterbury, E-mail: 06kb@kings-school.co.uk DOI: 10.4103/0974-6102.92207

A melanoma is a form of cancer that develops in the melanin-producing cells of the skin. Melanin is known to be noticeably abundant in the skin of grey horses as it is the pigment that makes some skin darker than others. Melanomas can be hard or soft and may be found to be solitary or amongst multiple groups massed in certain areas of the horse. Often they are located subcutaneously and are not visible to the naked eye as they are covered by normal haired skin; however, they may become ulcerated and infected. Typically, they are dark brown to black or grey, but some are non-pigmented. Diagnosis of non-pigmented (amelanotic) melanomas requires microscopic examination of biopsy specimens. Equine melanomas are differentiated solely by the terms of either being benign or malignant. They are not classified into stages as is the case with human melanomas. Many human melanoma patients die merely 12 months after diagnosis, dependent on the stage to which the melanoma has progressed, as the usual metastasis of cancer cells is quick and consistent in the body. However, in comparison to humans, grey horses have been said to hold the â&#x20AC;&#x2DC;secret to survival from melanomasâ&#x20AC;&#x2122;. Dr. John Powderly, whose expertise on melanoma in several species including both human and horses, said melanomas in horses are known to act very differently from those found in humans. They are usually only locally invasive and are slow growing. The round, usually black nodules [Figure 1] are most commonly found under the tail and around the vulva or rectum as shown in Figure 1, near the base of the ears, around the neck and jugular groove Young Scientists Journal | 2011 | Issue 10

Figure 1: Black nodules [available from http://www.ride-the-sunshineglow.com/equine-melanoma.html]

(the indentation on the side of the neck where the jugular lies between muscle groups) as well as around the eyes. Although these lumps are generally smooth and not painful, should the melanomas begin to metastasize, devastating consequences could occur. For instance, cancerous lumps which develop deeper within the internal body system of the horse, within the abdomen or chest could add pressure and potentially inhibit the function of vital organs. If the lump is developed in the abdomen, the first symptom is often recurrent bouts of colic, with the intervals between episodes becoming shorter. Alternatively, horses with massive cancerous lumps that infiltrate their intestines will slowly become less able to absorb nutrients from their food. These horses will show slow but progressive weight loss, despite eating as much extra feed as you can provide. 75

The rapid distortion of the horse's face is common when melanomas have grown inside the head region of the horse due to the local invasion of the cancerous cells. Cancer cells spread quickly as they are transported around the body through the bloodstream, should they initially form as a lump in the spleen. As these small clusters of cells are deposited around the body, they will continue to grow to form yet more cancerous lumps. Some cancer tissues can even produce inappropriate hormones that disturb the normal hormonal balance of the animal. For example, mares with a type of tumour of the ovary, known as an equine granulose, are subject to the production of excess testosterone. This male hormone, normally at very low levels in mares, leads to stallion-like behavior and aggression towards other horses. Fortunately, this particular cancer is usually surgically removable and the mare can experience full recovery after the cancerous ovary is removed. It is estimated that benign forms of the tumour are found on about 80% of grey horses over the age of 15 years. [1] In 2008, researchers at Uppsala University, Sweden, identified the genetic mutation that governs the greying process. The presence of an identical genetic mutation from a common ancestor of all grey horses which lived thousands of years ago, has also been discovered through the study. “By taking our genetic map and mapping the markers on DNA collected from a large number of progeny from a grey stallion, we were able to map where the grey locus (the position of a particular gene on a chromosome) was on the horse genome-and found it’s on horse chromosome 25 in a particular place,” explains Dr. Matthew Binns, Head of Genetics at The Animal Health Trust at Newmarket.[2] This proves how humans have specifically chosen attractive mutations in domestic animals.

bridle, and halter application if they obstruct paths for such items on the horse. The price of most melanoma treatment (as with most veterinary charges) is far from low in terms of finance.

Diagnosis of Melanomas Simple diagnosis of tumours is made by using a microscope. It is a relatively simple task involving taking a piece of the mass and identifying the presence of characteristic dark, black granules of melanin within the tumour cells [Figure 2], thereby confirming the disease. Small melanomas within the guttural pouches and the abdomen of horses can be found and monitored with the aid of medical instruments such as laparoscopes/endoscopes. A more complex examination, such as cytologic examination, reveals two different melanocytes, either pleomorphic or atypical. Melanomas are characterized by sheets, packets and cords of atypical melanocytes. These lesions most commonly occur in close association with hair follicles and epithetical sweat glands. In humans, dogs and cats melanomas usually form within close contact of the epidermis and dermoepidermal junction, which differ from horses. Melanoma identification can be further confirmed by the positive testing of vimentin.

Treatments of Melanomas Veterinarians recommend a vigilant approach to melanomas as operation can ‘activate’ the cells and increase the chance of tumour growth. Melanomas should only be operated on if they are causing harm to the horse. For example, large masses that interfere with and therefore disallow the horse to be ridden,

The discovery of the gene is particularly significant to medical researchers as the risk of melanomas is enhanced by this mutation. Both STX17 (syntaxin-17) and the neighboring NR4A3 gene are over-expressed in grey horses with melanomas, and those carrying a lossof-function mutation in ASIP (agouti signaling protein) have a higher incidence of melanoma, implying that increased melanocortin-1 receptor signalling promotes melanoma development in grey horses. Despite their type and nature, both benign and malignant melanomas can be practical as well as financial nuisances. As they can preclude saddle, 76

Figure 2: Melanoma cells [available from http://nabuleong.tistory. com/582]

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and those which prohibit the horse from defecating, have to be treated. Treatments that may be useful in dealing with equine melanomas include environmental management, wide surgical excision, cryonecrosis, biological response modifiers, and chemotherapy. A consistently satisfactory form of treatment still does not exist.

Solution 1 - Surgical Excision and Cryonecrosis Melanomas in easily accessible anatomic regions (tumours which are on the surface of the skin) of a relatively small size (less than 3 cm in diameter) which are not numerous (less than 15), can be treated by wide surgical excision [Figures 3, 4a and 4b]. Wide surgical excision is the removal of tissue using a scalpel or other cutting instruments, removing the entire melanoma and a certain width border of the surrounding normal-looking skin, depending on the depth of the melanoma.

Figure 3: A photo showing the wound left after surgical removal of a tumour [available from http://www.acvs.org/AnimalOwners/ HealthConditions/LargeAnimalEquineTopics/SkinTumorsInHorses/]

Additional tissues, usually skin and fat, are also removed from under the melanoma. This method generally refers to melanomas found in the perineal and perianal areas which may then be clinically managed by cryonecrosis as primary entity to surgical excision of cutaneous melanomas. It is also applied for the treatment of tumours which preclude removal by surgical excision, although excision is usually used to reduce tumour recurrence before cryonecrosis. Risks The main risk of using surgical excision and the reason that it is not seen as an ideal treatment solution is due to the rapid reoccurrence of melanomas from abnormal melanoblasts near to the surgical field. In some circumstances, coalescence of multiple smaller melanomas could lead to the development of huge undulating sheets of black tumorous tissue. The remaining cells are then cryonecrized to −20°C before being allowed to thaw. The cells are then re-cryonecrized once more.[3] It is essential that the process of cryonecrization takes place faster than the body’s ability to thaw the treated tissue. Despite the fact that this type of melanoma is rarely cured, it can be managed by cryonecrosis once or twice a year. Cryonecrosis can usually be accomplished in standing, sedated horses, in some horses; however, general anesthesia may be required. Particularly in large horses, the risks of anesthesia should not be Young Scientists Journal | 2011 | Issue 10

Figure 4a: A tumour pre-operation [available from http://www. carolinaequineclinicnc.com/casestudy-melanoma.html]

Figure 4b: Post-operation [available from http://w w w. carolinaequineclinicnc.com/casestudy-melanoma.html]

out ruled as a recent detailed survey concluded that 1 in a 100 horses die due to the anesthesia process.[4]

Solution 2 - Cimetidine Medical management of melanomas is the more traditional approach. The use of Cimetidine as a beneficial treatment for horse melanomas was first discovered in 1985. Malignant tumours in both humans and animals can be effectively treated by Cimetidine, a recognized biological response modifier. Cimetidine is a drug usually used to deal with stomach ulcers in horses and humans. This drug also has a potent effect on some melanomas and, while not curative, can effectively reduce the size of melanomas. Patients who suffer with neoplastic disorders may have suppressor T-cells that alter the bodyâ&#x20AC;&#x2122;s own antitumour defense mechanism. Histamine activates suppressor T-cells via H2 histamine receptors. Cimetidine blocks the activation of these cells, thereby augmenting cell-mediated and humoral immune responses. This can be evidently shown in Figure 5 as Cimetidine is proven to have increased the survival of colorectal cancer patients with high levels of sialyl Lewis-X and sialyl Lewis-A epitope expression on tumour cells. Comparison of the control group and patients treated with Cimetidine showed that the cumulative 10-year survival rate of the Cimetidine group was 84.6%, whereas that of the control group was 49.8%. This is an increased cumulative 10-year survival rate of 34.8% due to the effect of Cimetidine, thus identifying the significance of using the drug as an adequate and substantial solution to melanoma treatment.[5]

For melanomas which are actively increasing in both number and size, Cimetidine is found to provide the greatest of therapeutic benefits in horses, yet it has minimal effects on melanomas which have remained unchanged in size or appearance for many years. The horses which have responded best to the treatment were treated every eight hours with a dose of 2.5 mg/kg three times a day. Though if this administration cannot be delivered, a dose of 7.5 mg/kg per day will suffice.â&#x20AC;&#x2030;[3] Discontinuation of treatment is advisable if, after a three month period of treatment, there is no change in the number or size of melanomas. On the other hand, if therapy is seemingly successful and the melanomas appear to have decreased in size and number, then treatment should cease two to three weeks after positive response is no longer apparent. After cessation of Cimetidine administration, the succession of the disease may be haltered for months to even years. Benefits Response to treatment is not predictable, but a good reaction to treatment is deemed to be a reduction of 50% or more in both melanoma size and number and no further growth in several years. Changes in the number or size of melanomas during therapy typically become clinically discernible after two to seven weeks of treatment. In some cases, melanoma activity may be restored after a few years of disease quiescence.â&#x20AC;&#x2030;[5] Cimetidine can also be used in correspondence with other treatments such as cryonecrosis, surgical excision, or chemotherapy, as well as to decrease chance of melanoma reccurrence or to decrease size or number before surgical intervention. As far as scientists currently know, no toxic effects of Cimetidine treatment have been reported in horses. Therefore, Cimetidine is used with minimal risk in comparison to the consequences of using of the newer, more potent H2 antagonists which are not yet known. Not only this, but Cimetidine can be used without great expense and does not require excessively prolonged administration.

Alternative Solution 1 - Systematic Chemotherapy and Cisplatin

Figure 5: Effect of cimetidine on the survival of patients with colorectal cancers [available from http://www.nature.com/bjc/journal/v86/n2/ fig_tab/6600048f1.html#figure-title]

Cisplatin [Figure 6] is a platinum-based chemotherapy drug used to treat various types of cancers. According to recent investigations with cisplatin, solitary cutaneous melanomas may be sufficiently benefited by intralesional chemotherapy. But surgically debulking the melanoma, the potential local toxicity as well as the overall cost is decreased by minimizing Young Scientists Journal | 2011 | Issue 10

approximately eight months after treatment at the periphery of treated lesions. Benefits This is a highly useful drug as recurrent tumours do not develop resistance to cisplatin and can be treated a second time using the protocol used during the initial treatment.

Figure 6: A cisplatin molecule [available from http://www.clinbiochem. info/studentmagnesium3.html]

the quantity of drug used.[3] This procedure before the injection of cisplatin, although in smaller melanoma of a size less than two centimeters of diameter, does not require the initial debulking that is required before intralesional treatment. Four treatments are usually administered at two-week intervals with a dosage of 1 mg/cm of tumour each time. Yet leakages of cisplatin from the injection sites are inevitable with this dosage.The tumours should be individually injected with a 22- to 25-gauge needle with its tract filled by cisplatin as it is withdrawn. The cisplatin absorption ability of tissue is limited and so the injection tracks should be about 5 to 8â&#x20AC;&#x2030;mm apart. The administration of anti-inflammatory (phenylbutazone) drugs and systematic antimicrobial (potentiated sulphonamide or penicillin) reduces post-injection swelling. Cisplatin should be prepared immediately before it is injected, using a sesame oil carrier to prolong its effect. The reconstituted drug is stable at room temperature for 15 hours.[3] With local intralesional therapy, a tissue concentration that is significantly higher than that obtained following systemic (intravenous) therapy can be achieved with essentially no signs of toxicity. This form of treatment has been used on pregnant broodmares and breeding stallions without ill effect. Tumor resistance to cisplatin has not been described. Less-than-ideal therapeutic outcomes are most likely the result of inadequate tissue deposition of the drug secondary to less-than-optimum injection technique. Recurring melanomas usually become apparent by Young Scientists Journal | 2011 | Issue 10

Risks As with Cimetidine, the risks of use are minimal. The only risk that is seemingly worth mentioning is that there is the slight possibility of injection sites providing entrance sites for infection. Although with the current day standards of hygiene and sanitation being so high, this is a relatively small threat, however, it is not worth completely disregarding.

Alternative Solution 2 - Herbal Remedies For melanomas in general, the herbs which are recommended by Robert McDowell, a trained medical herbalist, as the combination for a basic support mix are; Equisetum, comfrey, yarrow, bladderwrack, ginseng, rose hip, and sage. The Bach Flower Remedies which are included are honeysuckle, holly, and Mimulus.[6] This amalgamation of these particular herbs helps to support one another, and addresses the damage done by the environment in general and the sun in particular. A 100 ml bottle of the mixture would be prescribed with dosage instructions of 20 drops, three times daily in water. This will provide six weeks of continuous treatment at costs ranging from ÂŁ50 to ÂŁ60. As the ingredients are purely natural, they should not cause any harmful side effects and are safe to use, without the added price of vet implication (the herbs can be given to the horse without the need of a vet). Therefore, the risks are minimal. In addition, Robert McDowell advises the administration of Maritime Pine Bark [Figure 7], an antioxidant, to dramatically stimulate the subject's immunity and ability to fight the cancer. Even with the many treatment modalities presently available for equine melanomas, the disease may still be difficult to manage clinically. Often, a successful therapeutic outcome mandates the use of combination therapy that takes into account the age of the horse, the time of the year, the number, 79

examined by a vet before purchase, the vet is now obliged to warn purchasers of the increased chance of melanoma development, and so purchasers may be put off buying a grey horse. The above reasons have led to some breeders even going to the extent of purposefully choosing to breed with the specific intention of avoiding grey offspring.

Ethical Issues

Figure 7: Maritime Pine Bark Extract [available from http://www. wellcorps.com/ingredients-benefits-maritime-pine-bark-extract.html ]

size, and progression of the lesions, and the financial limitations of the owner.

Social Issues As with most veterinary procedures, melanoma treatment can be very expensive. The initial ‘debulking’ of the melanoma using wide surgical excision alone, usually costs around £500 without any additional melanoma treatment costs added. On top of that, the initial diagnosis and examination fees must be taken into account as well as the cost of the horse staying overnight in the veterinary surgery as is often the case depending on the severity of the operation needed to remove the targeted melanomas. In addition to this, excision requires a highly trained vet with complex surgical expertise and extensive surgery equipment is needed for the procedure itself. Small veterinary practices may not fulfill such requirements; therefore, further travel to reach a veterinary surgery means further expenditure on the owner’s behalf as well as added stress for the horse. As previously stated, most melanomas which grow in grey horses are inactive and rarely metastasize to other parts of the body, therefore, owners can become negligent of the melanomas. This is not as an act of cruelty, but owners think that they can depend on the fact that melanoma growth will not be harmful to their grey horse, and so to avoid financial costs, choose not to treat them. However, if the melanomas are found to be of a malignant nature, this could lead to horse fatality or at the very least an increased amount of money to treat the melanomas at a more advanced stage. As a result of all of this, when grey horses are pre80

In compliance with some of the stated reasons above, such as that a potential purchaser can be put off buying grey horse due to increased melanoma development, we can see how selective breeding has now become increasingly apparent in the attempt to avoid breeding grey offspring. There are many issues with this phenotype manipulation of offspring by selective breeding and the desire to pass on favorable traits or to eliminate undesired traits. Selective breeding decreases the variety of alleles in the gene pool of that particular organism, therefore decreasing genetic diversity and prohibiting the natural process of evolution. The selectively bred species are likely to be more genetically prone to hereditary diseases as well as being more susceptible to other diseases as they may not inherit the genes which provide immunity against such diseases. It is obvious that this is becoming an increasingly dominant concern within horse breeding as more organisms are ending up with similar genomes and it is clear that horse breeders need to produce more heterozygous offspring with the grey allele to ensure the long term welfare of the species and keep the gene pool as diverse as possible. There also have been many debates on whether melanoma removal in grey horses should be allowed if it is purely for cosmetic reasons or if the horse is otherwise oblivious to its existence. Furthermore, members of certain religious communities strongly believe that horses with melanomas should not be treated as the natural body should not be altered.

Glossary Subcutaneously: Below the skin. Equine: Belonging to the family Equidae, which comprises horses, zebras, and asses. Mares: Female horses. Young Scientists Journal | 2011 | Issue 10

Laparoscope/Endoscope: A medical instrument consisting of a tube that is inserted through an incision in the abdominal wall to enable a doctor to examine the internal organs and perform operation. Cytologic: A branch of biology that deals with the formation, structure, and function of cells. Melanocytes: A pigment-producing cell in the skin, hair, and eye. Lesions: Infected patch of skin/wound. Vimentin: A family of proteins that is especially found in connective tissues. Scalpel: A sharp (surgical) knife. Perianal: Around the anus. Intralesional: Implies injecting a drug directly into the skin lesion for faster action and better results. (Amalgamation) Amalgamate: Combine or unite.

References 1. Melanoma, Virgina-Maryland, Regional College of Veterinary Medicine. Available from: http://www.vetmed.vt.edu/research/ CeCo/melanoma.asp [Last cited on 2010 Nov 18]. 2. Briggs H. ‘All the Grey Horses’, BBC News, October 9, 2002. Available from: http://news.bbc.co.uk/1/hi/sci/tech/2296131. stm [Last cited on 2002 Oct 09]. 3. Goetz TE. Melanomas in Horses-Case Study 2 ‘Treatment of Melanomas in Horses’, The Compendium, April 1993. Available from: http://www.miravalandalusians.com/garbosa/ melanom2.htm [Last cited on 1993 Apr]. 4. Horse Operations- What Actually Happens When a Horse is Given a General Anaesthetic. Available from: http://www. horserides.org/horse-operations.html [Last cited on 2010 Nov 18]. 5. Matsumoto S, Imaeda Y, Umemoto S, Kobayashi K, Suzuki H, Okamoto T. ‘Cimetidine increases survival of colorectal cancer patients with high levels of sialyl Lewis-X and sialyl Lewis-A epitope expression on tumour cells’. Br J Cancer 2002;86:1617, January 21, 2002. Available from: http://www.nature.com/ bjc/journal/v86/n2/fig_tab/6600048f1.html#figure-title[Last cited on 2002 Jan 21]. 6. McDowell, Robert, ‘Melanoma Herbal Support Treatment’ Available from: http://www.cancer-herbal-treatment.com/ herbs_melanoma_cancer.html [Last cited on 2010 Nov 18].

About the Author Katherine Burden studied for her A Levels at The King's School, Canterbury. Her hobbies include riding.

RCSU Science Challenge - Essay prize Submitted by cma on Tue, 13/12/2011 - 08:25 Organiser: Royal College of Science Union Age Limits: 12-20 Start Date: Launch 17 Jan 2012 Finish Date: Not yet announced, but probably Feb 2012 Prize: TBA at launch Launch event at Imperial College on 17 Jan 2012, featuring Lord Robert Winston, Pallab Ghosh, Mark Henderson. 4 essay titles will be announced at the launch, plus deadline and prizes. Final to be held on 22 Mar 2012 at the House of Lords. All winning entries in the 12-20 age range to be published in YOUNG SCIENTISTS JOURNAL! Young Scientists Journal | 2011 | Issue 10

Research Article

Knowledge of HPV and cervical cancer among women in Little Haiti Paula-Suzanne Lapciuc, Nadia Willy1 Ransom Everglades School, 1Miami Northwestern Senior High E-mail: paulasuzannelapciuc@gmail.com DOI: 10.4103/0974-6102.92209

ABSTRACT

Haitian women in Little Haiti have a higher cervical cancer incidence rate than women of other ethnic groups in Miami, Florida. In our study, we surveyed 246 women about their Pap smear screening behavior, as well as their knowledge of human papillomavirus (HPV) and cervical cancer. Data was collected as part of an ongoing Community-Based Participatory Research project called ‘Patnè en Aksyon’ (‘Partners in Action’). From our results, we were able to conclude that study participants have limited knowledge of HPV and cervical cancer, and they infrequently participate in Pap smear screening. Therefore, it is vital that Little Haiti’s female population learn more about HPV and cervical cancer in order to encourage disease prevention and reduce mortality rates.

Background Cervical cancer is a disease that occurs when abnormal cells in the cervix multiply uncontrollably. Most cervical cancers are caused by a sexually transmitted infection called human papillomavirus (HPV).[1] This disease is a growing cause of concern, particularly among ethnic minorities and medically deprived individuals. In the United States, Hispanic and Black women have the highest rates of cervical cancer. Among the country’s black women, those who are American born or Haitian born have higher rates of cervical cancer than those from the English speaking Caribbean.[2] In Miami, Florida, the incidence and mortality rates of cervical cancer are the highest among Haitian American women. Between 2000 and 2004, it was reported that about 38 out of 100,000 women were diagnosed with cervical cancer in Little Haiti. This number is about four times higher than the number of women diagnosed with cervical cancer in all of Florida during the same time period.[3] 82

Disparities in cervical cancer survival rates among different ethnic groups are partly due to difficulties in accessing medical services, including Pap smear screenings. [4] Pap smear screenings check for abnormal cervical cells, which may lead to cervical cancer,[5] and in doing so, help prevent cervical cancer through early detection of the disease.[6] Nearly 95% of women with cervical cancer have not had proper screenings before they are diagnosed with the disease. Immigrants, in particular, may have less opportunity to get regular Pap smear tests and therefore are not screened as often as American-born citizens.[7] The data seen for Haitian Americans is in agreement with these statistics; about one third of Haitian women in Little Haiti have never had a Pap test. Among those that have, only 44% have been screened within the past three years, contrary to the recommendation given by the national guidelines.[6] The area of Little Haiti contains the highest concentration of Haitians in the United States. This community encompasses one of the largest groups Young Scientists Journal | 2011 | Issue 10

of people living at or below the national poverty line; the poverty rate, 30%, is almost double that of Miami-Dade County’s, which is 18%.[8] Many of its inhabitants have limited literacy in English, and many others have limited proficiency in reading or writing Creole, their native language; this is another obstacle Haitian immigrants must overcome to access medical knowledge and aid. These and other factors may contribute to the high incidence of cervical cancer in Little Haiti’s community.[8] Our study examined one such factor: The knowledge of HPV and cervical cancer. Some theories suggest that a woman’s decision to seek health information or participate in Pap smear screening may depend on her fear of risk taking, opinions about healthcare, cultural values, confidence, and any prior knowledge that she may have.[4] The “health belief model” argues that if a person at risk of developing a certain health condition learns new information about it, he or she will attempt to prevent severe illness from occurring by methods that are necessary for prevention, such as check-ups and screenings.[9] Our study examined knowledge of cervical cancer and HPV among Haitian women living in Little Haiti, a predominately Haitian neighbourhood in Miami, Florida. By understanding this group’s current level of knowledge about HPV infection and cervical cancer, we were able to develop community based interventions to increase awareness about screening for cervical cancer and early detection of the disease.

risk factors for disease onset and progression. For our paper, we used data from this project to examine knowledge of cervical cancer and HPV. As discussed, we decided to focus on knowledge because increased awareness about cervical cancer risk factors and prevention may improve health outcomes among women in Little Haiti. Data for the study came from in-depth interviews with Haitian women living in Little Haiti conducted by Community Health Workers (CHWs) of Haitian descent. These CHWs also spoke English and Haitian Creole fluently. There were two full time CHWs that were hired and trained to recruit participants and collect information using a standardised training manual created by a researcher active in Patnè en Aksyon. This manual instructed CHWs on how to recruit participants and how to gather and manage study data. The CHWs approached Haitian women in many different locations who appeared to be 21 years of age or older and told them about the study. Women who met study eligibility criteria (21 years of age or older, no history of cancer, Haitian descent) and agreed to participate arranged a time to be interviewed by a CHW. The interviews occurred in places where the participant felt most comfortable. In most cases, the interviews took place in the participant’s home or the home of a friend. The participants chose whether to have the interview in English or Haitian Creole.

The data for our study came from an ongoing Community-Based Participatory Research (CBPR) project, known as ‘Patnè en Aksyon’ (‘Partners in Action’), started in 2004 by the University of Miami and members of civic organizations in Little Haiti. The overall goal of the project is to reduce cancer disparities within the South Florida Haitian community. Community-Based Participatory Research is a collaborative research method where trained scientific investigators work together with local community members to conduct studies that are pertinent to the district.[10] The co-operation of the scientific and local communities can help minimize health disparities.[11]

Between September 2007 and March 2008, the CHWs approached 362 women. Of the 362 women, 297 decided to participate; 290 were eligible and 250 actually completed the interview. A small percentage of women (seven percent) who expressed initial interest in the study refused interview. Most women who refused, feared that signing the informed consent documents would somehow affect their own or their family members’ immigration status. The interview took approximately one hour to complete and included questions about Pap smear screening history, risk factors for HPV infection, cervical cancer, and health in general. The questionnaire also incorporated HPV knowledge questions from the Health Information National Trends Survey, conducted by the National Cancer Institute twice each year.

Patnè en Aksyon supports multiple research projects to understand the excess burden of cervical cancer in Little Haiti. One of these projects examined known

All data from the questionnaires was entered into a statistical software program called Statistical Package for the Social Sciences (SPSS Statistics).

Materials and Methods

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SPSS is used by commercial, government, and academic organizations to solve business and research problems.[12] For our study, we used SPSS to generate descriptive statistics to test our hypothesis.

Results Table 1 shows that 67.2% of the respondents in our study sample had a family income of $15,000 or less per year. Nearly half (49.2%) of study participants had not received a high school diploma, and a staggering 44.3% were unemployed. The majority (54.1%) of inhabitants were recent immigrants, having come to the United States less than 10 years ago. Pap smear screening is used to detect abnormal cells in the cervix which may lead to cervical cancer. TableÂ 2 clearly indicates that most women in our sample (78.9%) had undergone Pap smear screening in their life time. However, only 60.2% of women in our sample had undergone one in the last three years. The American Cancer Society recommends that a woman is screened for cervical cancer every three years after she becomes sexually active.[13] Many women in our study claimed to have been screened less frequently than the national average.[14,15] Being screened routinely is the best method to detect early stages of cervical cancer and prevent mortalities from the disease.[1] Table 3 demonstrates the lack of knowledge surrounding cervical cancer among Haitian women in our study sample. A total of 68.7% of the women believed that being hit in your lower abdomen could cause cervical cancer. Most of the women (82.5%) also thought that if they are diagnosed with cervical cancer, they will die from the disease. Meanwhile, more than two thirds (72.8%) of the study sample incorrectly believed that multiple abortions can cause cervical cancer, and 76.8% of participants did not know that a high number of sexual partners increases your risk of this disease. The majority of the participants (77.6%) were also not aware women who smoke are more likely to develop cervical cancer than those who do not. Among the 246 women from Little Haiti who participated in the study, more than three quarters (78%) of respondents had not heard of HPV. As shown in Table 4, 81.7% of our sample of Haitian women did not know that HPV could cause cervical cancer, and 81.3% did not think that HPV is a sexually transmitted infection. An even greater percentage of 84

Table 1: Socio-demographic characteristics of study sample Characteristic Annual family income (n = 183) $15,000 or less More than $15,000 Educational attainment Less than high school graduate High school graduate and above Health insurance coverage No Yes Employment status Unemployed Employed part or Full time Years in the United States 10 Years or less More than 10 years

Percentage 67.2 32.8 49.2 50.8 85.3 14.7 44.3 55.7 54.1 45.9

Table 2: Pap smear screening Variable

Percentage

Have you ever had a Pap smear? Have you had at least one Pap smear in the last three years?

Yes 78.9 60.2

No 21.1 39.8

Table 3: Knowledge of cervical cancer Variable Do you think that being hit in your lower abdomen can cause cervical cancer? Do you think that most women diagnosed with cervical cancer die from the disease? Do you think that multiple abortions can cause cervical cancer? Do you think that having a high number of sexual partners increases your risk of cervical cancer? Do you think that women who smoke are more likely to develop cervical cancer than non-smokers?

Participants who answered incorrectly (%) 68.7 82.5 72.8 76.8 77.6

women (83.7%) incorrectly believed that HPV does not cause abnormal Pap smears. As shown in Table 5, of the 192 women in our sample who had not heard of HPV, 98.4% were born in Haiti, compared with 92.6% of the 54 women who had heard of HPV. Participants who had heard of the virus had also lived in the United States longer; about 87% of the women who had heard of it had been living in the United States for more than five years, compared with 71.9% of the women who had not heard of HPV. Furthermore, most of the women informed of this infection had had a greater success in education, employment, and income. There was almost a 30% difference in high school graduation rates among participants who had heard of HPV (74.1%) and those who had not (44.3%). Young Scientists Journal | 2011 | Issue 10

Table 4: Knowledge of human papillomavirus (HPV) Variable

Participants who answered incorrectly (%) 81.7

Do you think HPV causes cervical cancer? Do you think that HPV is a sexually transmitted disease? Do you think that HPV can cause abnormal Pap smears?

81.3 83.7

Table 5: Differences among Haitian women who reported having heard of human papillomavirus (HPV) and those who had not Heard of HPV Age 18-25 26 and older Born in the United States No Yes Years Lived in the United States Five years or less More than five years Education Less than high school graduate High school graduate and above Income $15,000 or less More than $15,000 Language-Monolingual Creole speaker No Yes Screening ever had a Pap smear No Yes Pap smear within the past three years No Yes

Yes (Total 54) Participants (%)

No (Total 192) Participants (%)

9 (16.7) 45 (83.3)

6 (3.1) 186 (96.9)

50 (92.6) 4 (7.4)

189 (98.4) 3 (1.6)

7 (13) 4 (87)

54 (28.1) 138 (71.9)

14 (25.9)

107 (55.7)

40 (74.1)

85 (44.3)

22 (48.9) 23 (51.1)

101 (73.2) 37 (26.8)

46 (85.2) 8 (14.8)

100 (52.1) 92 (47.9)

6 (11.1) 48 (88.9)

46 (24) 146 (76)

14 (25.9) 40 (74.1)

84 (43.8) 108 (56.3)

A total of 51.1% of the people who responded “yes” to having known about HPV earned more than $15,000 annually, and only 26.8% of the people who responded “no” earned more than $15,000, which is well below Florida’s median family income.[16] Many of the women (47.9%) who did not know about HPV were monolingual Creole speakers, compared with just 14.8% of the women who claimed to have heard of HPV. When the respondents were asked if they had ever had a Pap smear, almost one quarter (24.0%) of the sample that was not aware of HPV responded “no”. Only 11.1% of those, who were aware of HPV, had not had a Pap test. Out of the women from the study sample who had not heard of HPV, 56.3% had been tested within the past three years, compared with 74.1% that had previously heard of HPV. Young Scientists Journal | 2011 | Issue 10

Discussion Haitian American women living in Little Haiti, Miami, Florida, have an increased risk of developing and dying of cervical cancer. One reason that may account for this is the fact that many women living in Little Haiti may not be screened for cervical cancer as often as recommended by the national guidelines. The purpose of this study was to examine the knowledge of cervical cancer and HPV among Haitian women residing in Little Haiti. Our results suggest that a large portion of women who participated in the study are monolingual Haitian Creole speakers, have limited formal education, and are economically disadvantaged. Most of the women in the sample also falsely believed, perhaps influenced by their cultural and traditional backgrounds, that physical trauma may lead to diseases such as cervical cancer. Results from the study also indicate that many Haitian women residing in Little Haiti have limited knowledge of Pap smears, HPV, and cervical cancer. These linguistic, economic, social, and cultural barriers may make it more difficult for Haitian women living in Little Haiti to access or understand health related information about cervical cancer risk factors and disease prevention. This research was limited to the area of Little Haiti, thus the size of the sample was relatively small (246 participants) considering that Little Haiti is home to the largest population of Haitian immigrants in the United States. The majority of respondents had never heard of HPV, so only 22.0% were able to answer the remainder of questions on the survey concerning HPV. However, despite these limitations, study results clearly show that the majority of Haitian women in our sample had limited or incorrect knowledge about HPV and cervical cancer. There were also significant socioeconomic differences among those women who had not heard of HPV and those that had. Findings from this study may encourage communitybased interventions to increase knowledge about HPV and cervical cancer in Little Haiti, and other similar immigrant communities trying to tackle the problem. This knowledge may encourage women to take preventative action, including participating in routine screenings for cervical cancer, and ultimately reduce the number of women who die from this disease.

References 1. ‘Cervical Cancer: Prevention and Early Detection’, 2009, American Cancer Society. Available from: http://www.cancer.

2. 3.

4. 5. 6. 7. 8.

org/docroot/PED/content/PED_2_3X_Pap_Test.asp+best+meth od+for+early+detection+of+cervical+cancer cd=3 and hl=en and ct=clnk gl=us. [Last cited on 2011 Nov 10]. Williams DR. Racial/ethnic variations in women’s health: The social embeddedness of health. Am J Public Health 2002;92:588-97. Blanco J, Kobetz E, Barbee L, Ashlock B, Jacques M, August PD, et al. Knowledge about HPV and Cervical Cancer in Little Haiti, Miami, FL. Poster presented at University of Miami, Institute of Women’s Health Research Day. Stark A, Gregoire L, Pilarski R, Zarbo A, Gaba A, Lancaster WD. Human papillomavirus, cervical cancer, and women’s knowledge. Cancer Detect Prev 2008;32:15-22. Pap Test. Women’s Health. Jan. 2009. US Department of Health and Human Services. Available from: http://www.womenshealth. gov/faq/pap-test.cfm. [Last cited on 2011 Nov 10]. Kobetz E, Menard J, Barton B, Pierre L, Diem J, Auguste PD. Patnè en Aksyon: Addressing cancer disparities in Little Haiti through research and social action. Am J Public Health 2009;99:1163-5. Fruchter RG, Remy JC, Burnett WS, Boyce JG. Cervical cancer in immigrant Caribbean women. Am J Public Health 1986;76:797-9. Cruz-Taura A, LeVeen Farr J. Miami, FL: The Little Haiti Neighbourhood. Federal Reserve Bank of Atlanta. Available from: http://www.frbsf.org/cpreport/docs/miami_fl.pdf. [Last cited on 2011 Nov 10]. Glanz K, Rimer BK, Viswanath K. Health Behavior and Health Education: Theory, Research, and Practice. San Francisco:

Jossey-Bass; 2002. 10. About Community Based Participatory Research, 2009. Academic Autistic Spectrum Partnership in Research and Education. Available from: http://aaspireproject.org/about/cbpr. html. [Last cited on 2011 Nov 10]. 11. Community-Based Participatory Research, 2009. Communitycampus Partnerships for Health. Available from: http://depts. washington.edu/ccph/commbas.html. [Last cited on 2011 Nov 10]. 12. SPSS Press Releases, 2009. SPSS Inc. Available from: http://www. spss.com/press/template_view.cfm?PR_ID = 1048. [Last cited on 2011 Nov 10]. 13. ‘Can Cervical Cancer Be Prevented?’ Cancer Reference Information, 2009. American Cancer Society. Available from: http://www.cancer.org/docroot/CRI/content/CRI_2_4_2X_Can_ cervical_cancer_be_prevented_8.asp?sitearea=. [Last cited on 2011 Nov 10]. 14. Green EH, Freund KM, Posner MA, David MM. Pap smear rates among Haitian immigrant women in eastern Massachusetts. Public Health Rep 2005;120:133-9. 15. National Center for Chronic Disease Prevention and Health Promotion: Behavioural Risk Factor Surveillance System, Atlanta, GA: Centers for Disease Control and Prevention; 2008. 16. Median Family Income in the Past 12 Months by Family Size, 2008. U.S. Census Bureau. Available from: http://www.census. gov/hhes/www/income/medincsizeandstate.html. [Last cited on 2011 Nov 10].

About the Author Paula-Suzanne Lapciuc and Nadia Willy attend Ransom Everglades School and Miami Northwestern Senior High respectively. Both enjoy taking part in their school’s sports teams and actively read around their chosen subjects. In the summer of 2009, Paula Suzanne and Nadia were interns at the Department of Epidemiology at the University of Miami, where they conducted research on cervical cancer. Paula-Suzanne Lapciuc is 19 years old, she was born and raised in Miami, Florida, but currently lives in New York City and attends Columbia University. Throughout her life, she has had a passion and excitement for learning about different cultures and exploring public health effects among various communities. At 16, she went to Tanzania and lived amongst an impoverished community in the outskirts of Arusha. The atrocious health conditions left her with a desire to help those in distress. The next year she interned in the University of Miami’s Howard Hughes Medical Institute at the Department of Epidemiology. Under Dr. Erin Kobetz and her team, she studied and observed the effect of cervical cancer among the Haitian women in the community. These experiences have led her to pursue a major in epidemiology and human nutrition.

Young Scientists Journal | 2011 | Issue 10

Author Index, 2011 Bak M. A dual nature of light Bonilla G. Noctilucent clouds or polar mesospheric clouds Burden K. Melanomas and their effect on the grey horse Clark S. Water as an alternative fuel Dunn K see Goldsmith W et al Faure J. Can space-based solar power save the climate? Flores PB. Editorial Flores PB. Editorial Gearing S see Goldsmith W et al Goldsmith W, Gearing S, Dunn K, Harvey G, Swire C. Engineers' advice to students Greaves E. From hominids to humans: An overview of the evolution of man Harvey G see Goldsmith W et al Hilton N. Climate change: Our choice Jakpor O. Do artificial nails and nail polish interfere with the accurate measurement of oxygen saturation by pulse oximetry? Jenkinson F. A review of 10 of the best Origin of Life books

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73 13 75 30

20 1 43

38 46 7

33 65

Lapciuc P, Willy N. Knowledge of HPV and cervical cancer among women in Little Haiti 82 Loyn C. Can nuclear power save the climate? 16 Lui K. Can "terra preta" be used to combat climate change? 24 Mahapatra A, Nanda R. Bio-diesel and Bio-gas: Alternatives of the present 4 MartĂnez LC. Interview with Dr. Gabriela Olmedo 71 MartĂnez LC. Interview with Dr. Luis Delaye 68 Maybee B. The role of supernovae in the origins of life 56 Nanda R see Mahapatra A et al Pavlova A. Are we alone after all? 48 Robertson N. Harnessing the power of radioactivity 10 Swire C see Goldsmith W et al Swire C. Editorial 2 Swire C. Editorial 44 Swire C. The Endosymbiotic Theory 61 Swire C. The life-cycle of stars 52 Todd H. Top ten easy-read books on climate change 28 Willy N see Lapciuc P et al

Title Index, 2011 A dual nature of light

Engineers' advice to students

A review of 10 of the best Origin of Life books

Are we alone after all?

From hominids to humans: An overview of the evolution of man

Bio-diesel and Bio-gas: Alternatives of the present 4

Harnessing the power of radioactivity

Interview with Dr. Gabriela Olmedo

Can "terra preta" be used to combat climate change? 24

Interview with Dr. Luis Delaye

Knowledge of HPV and cervical cancer among women in Little Haiti 82

Can space-based solar power save the climate? 20

Melanomas and their effect on the grey horse

Noctilucent clouds or polar mesospheric clouds 13

Climate change: Our choice

The Endosymbiotic Theory

The life-cycle of stars

The role of supernovae in the origins of life

Top ten easy-read books on climate change

Water as an alternative fuel

Can nuclear power save the climate?

Do artificial nails and nail polish interfere with the accurate measurement of oxygen saturation by pulse oximetry? Editorial

1, 2, 43, 44

Young Scientists Journal | 2011 | Issue 10

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 The Butrous Foundation, which is take the journey through dedicated to empowering today the these pages is that this scientists of tomorrow. This book will help you foundation already publishes Young prepare for all your other journeys. Some of these will be Scientists Journal, the world’s first and physical ones, from place to place, such as to scientific only scientific journal of, by, and for, conferences. Others will be professional journeys, like from all the world’s youngsters (aged 12Botany to Astrobiology, or from lab intern to assistant to 20) who want to have science careers researcher to lab director. But the main ones, the most exciting or want to use science in other of all your journeys, will be into the Great Unknown. That is careers. 100% of proceeds from sales where all the undiscovered elements are, as well as all other of The Journeys Trilogy will go to the inhabited planets and every new species, plus incredible things Foundation to help it continue to like communication with dolphins in their own language, and fulfill its mission to empower technological innovations that will make today’s cutting-edge youngsters everywhere. marvels seem like blunt Stone Age implements. For further information please write to info@butrousfoundation.com 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

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

The Butrous Foundation

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

(ages 12-20 years) to participate in scientific advancements and to The Butrous encourage them toFoundation express their ideas freely and creatively. The Butrous Foundation is a private foundation established in 2006. The TheButrous current interestFoundation of the foundation is to fund activities that serve its mission. Butrous Foundation The Mission

The Butrous Foundation is a private foundation established in TheThe foundation aims to motivate young people to pursue 2006. current interest of the foundation is to scientific fund activities careers by enhancing scientific creativity and communication skills. that serve its mission. It aims to provide a platform for young people all over the world The(ages Mission 12-20 years) to participate in scientific advancements and to Theencourage foundation aims to motivate young people to pursue them to express their ideas freely and creatively. scientific careers by enhancing scientific creativity and Thematic approaches to achieve the foundation mission: communication skills. It aims to provide a platform for young 1. To enhance communication and friendship between young people peopleall allover over world (ages 12-20 years) to participate in thethe world and to help each other with their scientific scientific advancements and to encourage them to express their interests. 2. To promote ideals of co-operation and the interchange of ideas freely and the creatively. knowledge and ideas. 3. To enhance the application of science and its role in global soThematic approaches to achieve the foundation mission: ciety and culture. 1. To communication and young 4. enhance To help young people make links withfriendship scientists in between order to take advantage of global knowledge, and participate in the advancepeople all over the world and to help each other with their ment of science. scientific interests. 5. To encourage young people to show their creativity, inspire them 2. To promote thefull ideals of co-operation and the of to reach their potential and to be role models for interchange the next knowledge and ideas. generation. 6. To encourage discipline of of good scienceand where 3. To enhance thethe application science itsopen roleminds in global and respect to other ideas dominate. society and culture. 7. To help global society to value the contributions of young 4. To help young people make links with scientists in order to people and enable them to reach their full potential, take advantage of globaljournal knowledge, and participate in the visit Young Scientists www.ysjournal.com

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.