JUST Volume II Issue II SPRING 2017

Volume II Issue II

Beam Me Up, Scotty

An Insight Into Quantum Teleportation p. 19

Children and Game Theory // p. 28

Hyperoxia and Mitochondria // p. 24

Parasites, Pollution, and Streams // p. 34

A MESSAGE FROM THE DEAN OF CALS Dear Reader,

I’m pleased to congratulate the editors of the Journal of Undergraduate Science and Technology (JUST) on the successful completion of their second issue. The vision for JUST to serve as a premier undergraduate research journal is inspiring and aligns well with the Wisconsin Idea and the mission of the College of Agricultural and Life Sciences (CALS). As UW President Charles Van Hise called on us to do back in 1904, we support not only the search for truth, but also the dissemination of what we learn, for the benefit of the people of Wisconsin and those beyond our state’s borders.

Cutting-edge research at UW-Madison has led to developments that have bettered the world as we know it: the round silo, the Babcock butterfat test for milk quality, vitamins, hybrid corn, and numerous advances related to human health, economic development, and food production, among others. The Board of Regents proudly declared in 1894 that “the great state University of Wisconsin should ever encourage that continual and fearless sifting and winnowing by which alone the truth can be found.” The pages in this volume contribute to this important search for truth and reflect our desire to share the discoveries that result from that search. This is the Wisconsin Idea in action.

Not all research will change the world in the ways that Nobel-prize winning work has done, but participation in undergraduate research significantly shapes a student’s time at UW-Madison and leaves a lasting imprint on both the student and the campus. Students who engage in undergraduate research report closer connection to faculty members and meaningful amplification of their classroom learning. And part of the wonder of research is that we never know in advance which project will lead to what discoveries.

JUST provides an opportunity to highlight undergraduate research while engaging students in publishing, refining essential writing skills, and promoting science literacy. I am proud to support opportunities for students to become involved in research and to share the fruits of that labor. I invite you to join the authors here in the proud tradition of sifting and winnowing, and to join me in congratulating them on their impressive accomplishments.

On Wisconsin!

Sarah K.A. Pfatteicher, Ph.D. Associate Dean & Research Professor

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LETTER FROM THE EDITOR IN CHIEF Dear Reader,

In celebration of the one year anniversary of the Journal of Undergraduate Science and Technology (JUST), I would like to start off this letter by recognizing the student researchers and JUST board members who have made this publication and organization what it is today. Moreover, without the generous support from the College of Agricultural and Life Sciences and the Holtz Center for Science and Technology Studies, the publication of our second issue would not have been possible. Thus, my sincere thanks goes out to everyone who has contributed to JUST over the past year.

JUST was established with the goal of expanding opportunities for undergraduate researchers at UW to share their research with the Madison community. Since Fall 2015, our organization has grown significantly to offer students the opportunity to not only do just that, but also learn how to strengthen their scientific writing and editing abilities through peer review, to collaborate with expert faculty researchers to refine their research, and to explore the intersections of science and art through web, infographic and layout design. We recognize that undergraduate research is worth sharing as much as it is worth pursuing, and we are fortunate to serve as a platform that is dedicated to disseminating research conducted by some of the most brilliant students to the Madison community.

Each semester, I am amazed by the quality and range of research submissions that JUST receives—and this semester is no exception. In this issue of JUST, you will find editorials and research reports that cover a variety of sciencerelated topics. From economics, mathematics and psychology to molecular biology, environmental conservation and ecology, the breadth of scientific disciplines featured within is not only impressive, but is also a reflection of the great diversity and wealth of research found at UW.

This year marks the end of my time as Editor-in-Chief of JUST. As CoFounder, I have watched JUST grow from the very beginning and I am amazed at how far it has come. While we have accomplished much together in one year, I look forward to seeing JUST continue to grow and support undergraduate researchers in the years to come. In closing, it is with great honor I present to you the Spring 2017 issue of JUST. Sincerely,

Edward Ruiz Founder, Editor in Chief

Volume II Issue II Spring 2017 Editor in Chief Edward Ruiz

Managing Editors Lucy Kohlenberg Bailey Spiegelberg

Manager of Submissions Emma Hazel

Finance Chair Amanda Padlo

Treasurer Jieun Heo

Director of Design Margaret Seybold

Design Editor Alexa Machnik

Webmaster

Cayman McKee

Editors of Content Madelyn Goedland Noah Johnson Jeremy Mandel Meng Lou Sam Tesch Greg Zilberg Annie Novak Evan Cory Rose Walters Eric Clapper Alyssa Joachim Amirah Mat Lani Andrew Elton Jieun Heo Hope Beyer Teja Karimikonda

Copy Editors Alice Vagun Brittany Seefeld

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TABLE OF CONTENTS TEAM PAGE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 EDITORIAL // BIOTECHNOLOGY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Madelyn Goedland EDITORIAL // EVOLUTIONARY GENETICS. . . . . . . . . . . . . . . . . . . . . . . . . . 8 Evan Cory EDITORIAL // HEALTH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 .

Bailey Spiegelberg EDITORIAL // MOLECULAR BIOLOGY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 .

Meng Lou EDITORIAL // QUANTUM PHYSICS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 Rose Walters REPORT // HYPEROXIA AND MITOCHONDRIA. . . . . . . . . . . . . . . . . . . . . . 24 Megan Shwarz REVIEW // CHILDREN AND GAME THEORY. . . . . . . . . . . . . . . . . . . . . . . . .28 Carlos Ramiro REPORT // PARASITES, POLLUTION, AND STREAMS. . . . . . . . . . . . . . . . 34 Sarah Di Bartolomeo

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// Biotechnology

Personalized medicine: Printing Your Own Future

How can we make medical treatments better for patients? Personalized Medicine! Advancements in tissue engineering, regenerative medicine, and medical genetics are offering new opportunities for medical professionals and scientists to tailor medical treatments to the specific, unique needs of individual patients. This personalization of medicine could drastically improve the effectiveness of medical treatments for patients in the future.

I

f you were to go to the hospital today for an illness, you would likely receive the same medical treatment as another individual with a similar ailment even though that individual may vary in age, gender or ethnicity from you. Despite these differences, the field of medicine often utilizes a “one-size-fits-all” approach to serve its patients.

However, the unique genetic makeup of an individual has a significant impact on that person’s health and how these “universal” treatments will be tolerated by the body.

As a result, the field of personalized medicine has gained much attention in recent years. This method tailors a medical treatment plan to the characteristics, needs and preferences of each individual patient [1].

In the case of organ transplants, few patients today know that instead of waiting for an organ donor with the perfect compatibility, they can potentially participate in personalized medicine by procuring an artificial organ derived from their very own cells. Currently, in the United States, more than 120,000 people are on the waitlist for a life-saving organ transplant, with the addition of another individual every ten minutes [2]. However, a large shortage of donors is

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insufficient to fulfill this demand, with only about 11,700 organ donations made annually [2]. One novel solution to this shortage is the development of engineered tissues through a derivative of personalized medicine: 3D bioprinted organs.

Since its birth in 1986, 3D printing has been utilized in many, if not all, aspects of STEM applications, spanning form aeronautics to tissue engineering. 3D printing employs the concept of additive printing to allow the formation of a three-dimensional object in a highly accurate and consistent manner. Similar to how your traditional printer creates a two dimensional image through

"Few patients today know that instead of waiting for an organ donor with the perfect compatibility, they can potentially participate in personalized medicine by procuring an artificial organ derived from their very own cells.

"

a series of one-dimensional lines, 3D printing fabricates a threedimensional object from layers of two dimensional “images”. If one can mold plastic, glass, metal and even food into any shape and form, why not cells?

The very first inkjet printers used for 3D bioprinting were simply modified versions of commercially available 2D office printers. Instead of providing ink within the printer cartridges, biological materials, such as living cells, proteins and interstitial

structures are substituted and printed upon an adjustable stage [3]. Once one layer of material is successfully printed, the stage lowers, allowing for another layer to be deposited upon the first. Through this repetitive process of administration and solidification, a three-dimensional product is obtained. Since 2D inkjet printers are widely available, a fully customizable setup can be achieved for a relatively low price.

This method also provides high resolution and speed, which are critical for tissue organization and cell survival.

via reprogramming into any type of cell in the patient’s body through a stem cell intermediate. Using cells obtained from oneself decreases the probability of triggering negative immune responses that are often associated with rejection of transplanted organs from foreign sources, such as another person or animal [5]. These techniques have been successfully utilized to grow functional heart valves and bladders with the aid of biomaterial scaffolds and have been successfully transplanted into patients [4, 6]. Until fairly recently,

"Three-dimensional

tissue generation has begun to gain momentum for less complex applications. Tissue samples can be collected from a localized area of a patient, grown outside the body, and then be transplanted without manipulation back into that same individual to aid in regeneration.

"

Large strides have been made in laboratories across the world in growing the many different cell types that comprise the human body in a dish: Heart muscle cells capable of contracting on their own in a synchronized fashion, neurons that develop complex communication networks and epithelial cells that organize themselves into vascular tubes. Countless researchers have demonstrated the resilience and potential of tissue growth in vitro, or outside of the body [4]. The next step of this pipeline is to mediate the transition between cultured cells and full-scale organ regeneration — a feat possible through 3D organ bioprinting.

Three-dimensional tissue generation has begun to gain momentum for less complex applications. Tissue samples can be collected from a localized area of a patient, grown outside the body, and then be transplanted without manipulation back into that same individual to aid in regeneration. Likewise, a simple cheek swab from a patient can be used to recover cells that can be manipulated

Structures such as this can be 3D-printed and used as support scaffolds for cells ready to be modeled into usable tissue for implantation into patients in need.

backbone structures like these have been primarily made by careful mechanical manipulation in a machine-independent fashion, introducing susceptibility to human error in crafting such structures.

Today, there are biomaterial 3D printers with smaller margins of error capable of accurately generating the scaffold of transplanted organs [6].

Although the concept itself is promising, it is important to note that 3D bioprinting adds another layer of complexity to the equation: Living tissue. Due to the highly selective nature of cells, choice of material, growth and differentiation factors and biomechanical patterns become crucial when it comes to crafting 3D printed organs. In order to fully recapitulate native functional tissues, 3D bioprinters need to be further adapted to a wider range of biological components of the microenvironment before reaching their full potential. In order for these organs to be successfully translated from the lab bench into common clinical applications,

these methods will require further optimization of printing speed and biocompatibility. In addition, quality standards and regulations will also need to be addressed by the FDA.

The field of personalized medicine is advancing the health care system toward a more predictable, powerful and individualized patient experience.

Continued research will hopefully mitigate the effects of genetic makeup on health, disease and drug response in order to provide the ideal care to each unique individual, creating a medical community in which each individual treatment can be tailored to match the extensive diversity of the population.

--Madelyn Goedland REFERENCES

1.

"Paving the way for personalized medicine: FDA’s role in a new era of medical product development," in U.S. Food and Drug Administration, 2013. [Online].

Available: http://www.fda.gov/downloads/ S c i e n c e R e s e a r c h / S p e c i a l To p i c s / PersonalizedMedicine/UCM372421.pdf.

Accessed: Nov. 27, 2016.

2.

"OPTN: Organ procurement and transplantation network," 2016. [Online].

Available: https://optn.transplant.hrsa. gov/. Accessed: Nov. 5, 2016.

3.

L. Gilpin, “3D 'bioprinting': 10 things you should know about how it works,” TechRepublic, 23-Apr2014. [Online]. Available: http://www. techrepublic.com/article/3d-bioprinting10-things-you-should-know-about-howit-works/. [Accessed: 17-Nov-2016].

4.

F. J. O’Brien, “Biomaterials & scaffolds for tissue engineering,” ScienceDirect.

Marc-2011.

[Online].

Available: http://www.sciencedirect.com/ science/article/pii/S136970211170058X. Accessed: 17-Nov-2016.

5. “Advanced Immunology: Transplantation," Immunopaedia. [Online].

Available: http://www.immunopaedia. org.za/immunolog y/advanced/1transplantation/. Accessed: 15-Nov-2016.

6.

R. Weiss, “First Bladders Grown in Lab Transplanted,” Washington Post, 04Apr-2006. [Online]. Available: http://www. washingtonpost.com/wp-dyn/content/ article/2006/04/03 /AR2006040301387. html. Accessed: 15-Nov-2016.

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// Evolutionary Genetics

Ancient DNA

What does ancient DNA extracted from the remains of our ancestors tell us? Advancements in DNA sequencing technologies have enabled researchers to better understand how our DNA has changed over time, giving insight to the evolution of man through genetic changes over time. The wealth of information that can be found within ancient DNA may reveal more about our current selves than researchers ever thought.

A

s part of the International Steenbock Lecture Series, the University of Wisconsin-Madison hosted world renowned researcher Svante Pääbo (sv-AH-nte p-AY-b-oh) in December 2016. To place Pääbo into an academic niche proves difficult — he is a world leader in the fields of anthropology, genetics, evolution and molecular biology, with many even going so far as to name him the ‘father of evolutionary genetics.’

Pääbo’s prolific research career has brought him into intimate contact with genomes of all kinds, ranging from ancient Egyptian mummies to Neanderthals to extinct cave bears. In the 1980s, Pääbo overcame various technical issues related to isolating and characterizing deoxyribonucleic acid

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(DNA) from Ancient Egyptian Mummies [1]. Over the next decade or so, he became an expert in analyzing ancient DNA. Years later, Pääbo moved on to the archaic cousin

on smaller parts of the genome, such as the mitochondrial DNA and a few nuclear genes of Neanderthals [2]. Eventually, with the help of his collaborators, Pääbo

"With the completion of the Human Genome Project in 2001,

[Pääbo] and his colleagues could begin an unprecedented comparison and analysis of the two genomes to uncover genetic differences between the two and implications for human evolution in the approximate 400,000 years since the human lineage split from Neanderthals.

"

of humanity that went extinct around 30,000 years ago: The Neanderthal, or Homo neanderthalensis. Initially, Pääbo and his team were limited by poor DNA sequencing technologies, so they worked

announced he and his team had put together a draft sequence of the entire Neanderthal genome in 2010 [3]. This was the crown jewel for Pääbo. With the completion of the Human Genome Project in 2001, he

and his colleagues could begin an unprecedented comparison and analysis of the two genomes to uncover genetic differences between the two and implications for human evolution in the approximate 400,000 years since the human lineage split from Neanderthals [4]. In short, Pääbo has shaped and continues to shape the field of evolutionary genetics with his innovative research and has emerged as the world expert on ancient DNA. Sifting through the scientific literature, it’s difficult to find a publication concerning ancient DNA that doesn’t have his name all over the citations.

The rise of efficient DNA sequencing technologies starting in the late 1980s is essential to Pääbo’s research. The human genome contains around three billion base pairs (bp). The way we “read” the order of these bases is called sequencing. Prior to the 1980s, scientists were handicapped by their ability to only reliably sequence around 500bp at a time [5]. Sequencing whole genomes was impossible due to the low throughput nature of the technology. Luckily for researchers,

the early 1990s was a golden age for biotechnology with rapid advances in many molecular techniques, including sequencing.

One of the most pertinent advances of this golden age was highthroughput sequencing, which allowed for the generation of DNA sequences at a rate magnitudes faster than previous methods [6].

But, even with the new technologies, working with the ancient Neanderthal DNA presented challenges of its own. Pääbo spent a significant portion of his career developing complex protocols to determine reliable and authentic sequences from fragmented ancient DNA. A complication contributing to the amount of time he spent refining his protocols was the issue of contaminant DNA. The same properties of DNA that allow it to persist in archeological specimens for tens of thousands of years give other pieces of contaminating DNA extraordinary longevity as well.

When amplifying DNA in the process of sequencing it, a single piece of contaminating DNA can render the results useless [1]. A combination of new technologies, Pääbo’s decades of experience with ancient DNA, and a rational approach allowed his team to

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announce the draft assembly and analysis of the full Neanderthal genome in the May 2010 issue of the journal Science [3].

While the complete Neanderthal genome does reveal important information on the nature of Homo neanderthalensis, more significant findings appear from analyzing the Neanderthal genome in the context of human genetics. Detailed sequence comparisons between the two hominins provide an unprecedented level of detail on human evolution in the last few hundred thousand years. Put simply, by comparing the modern human to a hominin that we diverged from some time ago, Pääbo’s team identified versions of traits and genes novel to the human genome that may have had functional ramifications. Perhaps the most exciting result from this monumental project was the conclusion that early humans most likely interbred with Neanderthals.

Analysis of the frequency of single nucleotide polymorphisms — mutations in one base pair of DNA, known as SNPs — between the Neanderthal and Human genomes revealed Neanderthals are significantly more closely related to all non-African humans than to their counterpart populations that never left Africa. This data suggests Neanderthals exchanged genetic information with

"Pääbo’s

molecular findings suggest with strong data-driven evidence, modern Eurasian populations have 1 to 4% Neanderthal DNA due to gene transfer between populations of early humans and Neanderthals. This revelation fundamentally changes our understanding of early human population expansion.

"

early humans that left Africa. Previously, experts made arguments for and against human-Neanderthal interbreeding, both based on poor evidence [7,8]. Pääbo’s molecular findings suggest with strong data-driven evidence, modern Eurasian populations have 1 to 4% Neanderthal DNA due to gene transfer between populations of early humans and Neanderthals. This revelation fundamentally changes our understanding of early human population expansion.

Previous models claim a small African population of humans migrated and drove other archaic hominins to extinction by virtue of being more evolutionarily fit. The 1 to 4% Neanderthal DNA that persists today in non-African genomes brings along genetic relics that have suspected effects in humans.

For example, sequences imply that humans acquired Neanderthal versions of genes involved in keratin filament formation — a protein that makes up hair and fingernails — may have helped early humans adapt to harsher nonAfrican environments [3].

In light of Pääbo’s work on the Neanderthal genome, there are many genes worthy of further examination. One particularly intriguing gene is Forkhead Box Protein P2 (FOXP2), one

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of the only human genes known to be essential in the normal development of speech and language. Mutation or inactivation of this gene in humans causes severe disorders in language development [9]. Functional language is something uniquely human and constitutes a symphony of complex anatomical, physiological, neurological and genetic pathways. And while many of the exact functions of FOXP2 are not yet characterized, at this point, it is beyond reasonable doubt this gene plays a role in speech and language development. Now, to dig into the molecular basis behind this claim, we need to examine the evolutionary genetics of the gene. First, FOXP2 is an unusually conserved gene among mammals [10]. To be “conserved” in a genetic sense means the sequence of the gene is observed to be very similar across species over evolutionary. Conserved sequences like this tend to remain conserved unless a scenario where a mutation is favored by selection arises. Two mutations in FOXP2 became fixed in the time following the human lineage’s split from the chimpanzee. We know these mutations arose before many archaic hominins diverged from their common ancestor with humans because Neanderthals share the modern variant of FOXP2 almost identically with humans [11]. These two changes represent a significant increase in the rate of mutation at the FOXP2 locus, indicating the gene may have experienced a strong positive when selected in early hominin populations, possibly indicating that developing speech was an evolutionary boon to early humans [12]. In an effort to characterize the neurological implications of the human FOXP2,

Pääbo and his colleagues introduced the human version of FOXP2 into the genomes of mice and observed the phenotypic manifestations of this change. Through complex behavioral assays performed on mice, scientists observed the addition of the gene resulted in a tendency to rely on procedural learning more than the wild type mice. Procedural learning involves the “how” of solving problems and constructs complex neural circuits that provide long term, automatic responses to tasks. While the results of this study are far from conclusive on the role of humanized FOXP2 in mouse learning, one scenario they may suggest is that the human FOXP2 increased the efficiency of human procedural learning which allowed better language acquisition [13]. Whether or not

"While the results of this study are far from

conclusive on the role of humanized FOXP2 in mouse learning, one scenario they may suggest is that the human FOXP2 inceased the efficiency of human procedural learning which allowed better language acquisition.

"

FOXP2 is the “speech gene” many scientists hope it is, it is still a proof of concept in how evolutionary genetics and Pääbo’s research can provide insights into the mechanisms of selection that acted upon archaic hominins and produced the complex, intelligent and industrious species that dominates the earth today: Homo sapiens sapiens [14].

--Evan Cory REFERENCES

1.

Pääbo S. Ancient DNA: extraction, characterization, molecular cloning, and enzymatic amplification. Proc Natl Acad Sci U S A. 1989;86(6):1939-43. PubMed PMID: 2928314; PubMed Central PMCID: PMCPMC286820.

2.

Krings M, Stone A, Schmitz RW, Krainitzki H, Stoneking M, Pääbo S. Neandertal DNA sequences and the origin of modern humans. Cell. 1997;90(1):19-30. PubMed PMID: 9230299 3.

Green RE, Krause J, Briggs AW, Maricic T, Stenzel U, Kircher M, et al. A draft sequence of the Neandertal genome. Science.

2010;328(5979):710-22. doi: 10.1126/science.1188021. PubMed PMID: 20448178; PubMed Central PMCID: PMCPMC5100745.

4.

Lander ES, Linton LM, Birren B, Nusbaum C, Zody MC, Baldwin J, et al. Initial sequencing and analysis of the human genome. Nature. 2001;409(6822):860-921. doi: 10.1038/35057062.

PubMed PMID: 11237011.

5.

Sanger F, Nicklen S, Coulson AR. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977;74(12):5463-7. PubMed PMID: 271968; PubMed Central

PMCID: PMCPMC431765.

6.

Bentley DR, Balasubramanian S, Swerdlow HP, Smith GP, Milton J, Brown CG, et al. Accurate whole human genome sequencing using reversible terminator chemistry. Nature.

2008;456(7218):53-9. doi: 10.1038/nature07517. PubMed PMID: 18987734; PubMed Central PMCID: PMCPMC2581791.

7.

Evans PD, Mekel-Bobrov N, Vallender EJ, Hudson RR, Lahn BT. Evidence that the adaptive allele of the brain size gene microcephalin introgressed into Homo sapiens from an archaic Homo lineage. Proc Natl Acad Sci U S A. 2006;103(48):1817883. Epub 2006/11/07. doi: 10.1073/pnas.0606966103. PubMed PMID: 17090677; PubMed Central PMCID: PMCPMC1635020.

8.

Currat M, Excoffier L. Modern Humans Did Not Admix with Neanderthals during Their Range Expansion into Europe. PLOS Biology. 2004;2(12):e421. doi: 10.1371/journal. pbio.0020421.

9.

Lai CS, Fisher SE, Hurst JA, Vargha-Khadem F, Monaco AP. A forkhead-domain gene is mutated in a severe speech and language disorder. Nature. 2001;413(6855):519-23. doi: 10.1038/35097076. PubMed PMID: 11586359.

10.

Enard W, Przeworski M, Fisher SE, Lai CS, Wiebe V, Kitano T, et al. Molecular evolution of FOXP2, a gene involved in speech and language. Nature. 2002;418(6900):869-72.

Epub 2002/08/14. doi: 10.1038/nature01025. PubMed PMID: 12192408.

11.

Krause J, Lalueza-Fox C, Orlando L, Enard W, Green RE, Burbano HA, et al. The derived FOXP2 variant of modern humans was shared with Neandertals. Curr Biol. 2007;17(21):1908-12 Epub 2007/10/18. doi: 10.1016/j. cub.2007.10.008. PubMed PMID: 17949978.

12.

Zhang J, Webb DM, Podlaha O. Accelerated protein evolution and origins of human-specific features: Foxp2 as an example. Genetics. 2002;162(4):1825-35. PubMed PMID: 12524352; PubMed Central PMCID: PMCPMC1462353.

13.

Schreiweis C, Bornschein U, Burguière E, Kerimoglu C, Schreiter S, Dannemann M, et al. Humanized Foxp2 accelerates learning by enhancing transitions from declarative to procedural performance. Proc Natl Acad Sci U S A. 2014;111(39):142538. Epub 2014/09/15. doi: 10.1073/pnas.1414542111. PubMed PMID: 25225386; PubMed Central PMCID: PMCPMC4191787.

14.

Pääbo S. The human condition-a molecular approach.

Cell. 2014;157(1):216-26. doi: 10.1016/j.cell.2013.12.036.

PubMed PMID: 24679537.

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// Health

The Fate Of Bacon: Will Its Link To Cancer Cause Its Doom?

Bacon has recently been classified as a Group 1 carcinogen, a substance that can cause cancer, by the World Health Organization. Does this mean the end of bacon as we know it? As is often the case with any foods, moderation is key.

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F

or some, the thought of having to eat breakfast on Saturdays without bacon is unbearable. However, this is the decision that mankind thought it would have to face when the World Health Organization’s (WHO) International Agency for Research on Cancer (IARC) announced in a press release that bacon and other processed meats would now be classified as a Group 1 carcinogen [1]. Does this mean the end to bacon-eating as the world knows it? Research suggests that there may still be hope for bacon-lovers.

A carcinogen is any substance that can cause cancer [2]. Through a meta-analysis, the IARC constructed a system to classify environmental factors and other substances on their carcinogenic potential. A substance in Group 1 is carcinogenic.

Group 2A contains substances that are likely carcinogens. Group 2B contains possible carcinogens. Group 3 encompasses nonclassifiable substances, while substances in Group 4 are likely not carcinogenic. Substances within Group 1 include bacon and other processed meats, in addition to ultraviolet (UV) rays, alcohol, tobacco, and asbestos [3]. Not only does this report recommend that we should no longer eat bacon, drink alcohol, or go outside, but also it suggests that these things are equally as bad as smoking and asbestos. How can this be true?

Well, in fact, that’s not quite the whole picture. The IARC’s classifications specify the carcinogenicity of a substance, but these classifications do not account for the degree of exposure needed for a substance to be considered carcinogenic [4]. This makes more sense when we compare tobacco and processed meat, both classified in Group 1. This classification indicates that the IARC is confident that the evidence for processed meat as a cancer risk-factor is as strong as the evidence for tobacco as a risk-factor; however, the risk of getting cancer from tobacco is much higher than that from processed meat. In fact, tobacco use will increase the risk of lung cancer by 2,500%, whereas regular bacon consumption will increase the risk of colorectal cancer by only 18%. Additionally, compared to lung cancers, colorectal cancer is a lower-risk cancer. Colorectal cancers account for 3% of all cancers, whereas lung cancers accounts for 19% of all cancers.

This suggests that the risk of developing cancer from processed meat consumption does not near the risk of that caused through tobacco use, despite a singular classification of these substances [4].

A carcinogen expert from King’s College London, Professor David Phillips provides an analogy to increase the understanding of why not only bacon, but also UV rays and alcohol, are categorized with tobacco and asbestos. This analogy proceeds as follows: A banana skin can cause an accident. It is unlikely, but it can happen. A car can also cause an accident, which can occur quite frequently. Both can cause accidents, but one with greater frequency and more harmful repercussions [5].

Ultimately, for all bacon lovers, it comes down to this: eating bacon doesn’t mean you will get cancer, but increased consumption will heighten your risk. So, maybe instead of eating six pieces of bacon come Saturday morning, eat two pieces every other Saturday. In this way, risks will be reduced and bacon will be enjoyed for years to come.

--Bailey Spiegelberg REFERENCES

1.

IARC Monographs evaluate consumption of red meat and processed meat. International Agency for Research on Cancer; 2015. http://www.iarc.fr/en/media-centre/pr/2015/pdfs/ pr240_E.pdf.

2.

Carcinogen. Merriam-Webster. http://www.merriamwebster.com/dictionary/carcinogen.

3.

Bacon Causes Cancer? Sort Of. Not Really. Ish. Zhang, Sarah; 2015. https://www.wired.com/2015/10/who-does-baconcause-cancer-sort-of-but-not-really/.

4.

Processed Meat and Cancer – What You Need to Know.

Dunlop, Casey; 2015. http://scienceblog.cancerresearchuk. org/2015/10/26/processed-meat-and-cancer-what-you-need-toknow.

5.

Diesel Exhaust Fumes “Definitely” Cause Cancer – Should We be Worried? Phillips, David. Interviewed by Scowcroft, Henry; 2012. http://scienceblog.cancerresearchuk. org/2012/06/14/diesel-fumes-definitely-cause-cancershould-we-be-worried/.

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Want your research featured here?

Now accepting

submissions for Fall 2017

w w w. ju stj ou r n a l. or g contact@justjournal.org also recruiting: EDITORS PEER REVIEWERS

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// Molecular Biology

Apoptosis: Degradation in Preventing Cell Death T

he commitment of a cell to apoptotic programmed cell death is as essential as it is irreversible – too much of which has been linked to neurodegradation and dysfunction; too little, an accumulation of mutant cells, transmission of defective genes, and proliferation of aggressive cancers. Classically mediated by stress, the canonical apoptosis activation pathway in mammalian cells is branched into two

holocytochrome c-dependent intrinsic pathway mediated by apoptosome multimerization [1]. In the intrinsic apoptosis central dogma, it is believed that pro-apoptotic proteins effectors BAK/ BAX, activated by BH3-only initiators and sequestered by multi-domain antiapoptotic protein BCL-2, are exclusively necessary in outer mitochondrial membrane permeability and therefore apoptotic

"A

recent investigation revealed an alternative non-canonical mitochondria outer membrane permeabilization (MOMP)–mediated apoptotic pathway mediated by BOK protein, one that is independent of BH3-only protein signaling and BCL-2 inhibition.

"

major sections: (i) a caspase 8-depedent extrinsic pathway that is triggered through death receptor stress signaling; (ii) a

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signaling. However, a recent investigation

by Llambi et al. in 2016 revealed an alternative non-canonical mitochondria

outer membrane permeabilization (MOMP)–mediated apoptotic pathway mediated by BOK protein, one that is independent of BH3-only protein signaling and BCL-2 inhibition [2].

Upon its initial discovery in 1997, BCL2 ovarian killer (BOK) shared striking sequence and structural homology to BAK/BAX [2,3]. Aside from its ability to slightly heterodimerize with antiapoptotic BCL-2 and induced death in the ovarian cells, its role in apoptosis

was largely ambiguous [3]. Further in vivo and in vitro studies involving BOK/- specimen failed to illustrate significant impact on proliferation of lymphomas and development in general [4]. To clarify the true effect of BOK on apoptosis, Llambi et al. generated BOK-/- mouse embryonic fibroblast (MEF) mutants as well as a Doxinducible Venus-BOK fluorescent fusion MEF line. Upon failure to find BOK protein despite presence of mRNA in the WT lines and Dox induction treatment, the authors proposed that BOK is under endogenous constitutive degradation [2]. As predicted, BOK expression upon treatment with proteasome inhibitors was observed through fluorescent imaging and induction of apoptosis, the latter of which was also attenuated by subsequent BOK-targeted siRNA silencing [2]. In a double knockout BAK-/-/BAX/- background, Llambi et al. also demonstrated caspase-dependent cell death with analogous characteristics of apoptosis (blebbing) after enforcing BOK expression via proteasome inhibition. The authors thus have expertly shown that BOK-triggered apoptosis acts in a BAK/BAX-independent manner (Fig.1).

Next, Llambi and colleagues focused the mechanism in which BOK degradation was controlled, leading them to explore BOK’s connection to the ER-associated degradation (ERAD) pathway in an apoptotic context. Endogenously, when overloaded with misfolded protein or oligomerized complexes, the cell activates endogenous ubiquitin- and proteasome-

microscopy illustrated strong colocalization of BOK with the gp78 Ub-ligase complex.

Llambi et al. also showed that knockdowns of gp78 and VCP lead to consistent BOK expression and induced stronger death phenotype. Finally, by compromising ERAD through inhibition of PERK along with TN stimulation, they revealed that the gp78 complex (responsible for BOK degradation) was in turn degraded under these conditions [2]. Through these perturbations of the components of the ERAD system, the

dependent mechanisms to degrade the proteins to relieve ER stress. The activated mechanism in mammalian cell utilizes gp78 for ubiquitination on lysine residues and valosin-containing protein (VCP) for elongation of the ubiquitin chain, as well as PERK for sensing and signaling [5]. Nonconservative lysine-to-arginine substitutions of BOK promoted stable expression by preventing gp78 E3-executed ubiquination [2]. Further live confocal

stabilized BOK expression initiated MOMP and therefore release of holocytochrome c [2]. The authors then dissected the necessity of BOK localization to the mitochondria on its activity by generating three variants of BOK: (i) truncation of the C-terminus transmembrane domain therefore cytosolic sequestering BOK; (ii) anchoring to the plasma membrane; (iii) anchoring BOK mitochondrial outer membrane. It was observed that only the latter BOK

form, anchored to the mitochondria, was functional. Differing from BAK/BAX, whose activation is BH3-only protein dependent, BOK in its endogenous multimeric form is constitutively competent and sufficient in permeabilizing the OMM [2]. Finally, through affinity precipitation and examining enzyme kinetics, BOK was not found to be sequestered by BCL-2 as BAK/BAX is (Fig.1).

In summary, Llambi and colleagues have extrapolated a novel pathway from a previously-known yet unexplored BCL-2 family member protein BOK through which intrinsic apoptosis may be induced. This

Figure 1. BOK-mediated apoptosis pathway in comparison to canonical intrinsic pathway. The BOK protein is regulated by components in the ERAD system (green box) and is normally degraded by endogenous proteasomes. It is interestingly independent from BH3 activation and anti-apoptotic BCL-2 protein suppression in inducing MOMP. Image adapted from2.

authors beautifully showed the dependency of BOK-mediated apoptosis on the ER stress response (Fig.1).

Further delving into the mechanism in which BOK is controlled, Llambi et al. compared its effects to that of BAK/BAX. Similar to BAK/BAX apoptotic effector,

"Llambi and colleagues have extrapolated a novel pathway from a previously-known yet unexplored BCL-2 family member protein BOK through which intrinsic apoptosis may be induced."

pathway differs from the BAX/BAK pathway in that being constitutively active it does not require BID activation [6]. Therefore, it is controlled by constant degradation associated with the integrity of ERAD activity, the disruption of which promotes stable BOK expression and triggering subsequent MOMP and apoptosis, much unlike the underlying mechanism of BAK/ BAX [6,7]. Finally and most remarkably, BOK activity is not attenuated by BCL2 antiapoptotic protein, giving it great potential in pharmacology. Despite its excellent and meticulous methodology, a limitation of this investigation lies in the in vitro nature of this investigation. Whether a similar pattern observed in MEF’s translates across cell types (aside from ovaries and fibroblasts) as well as microenvironments are left unanswered and should be explored before application to medicine.

Nevertheless, the discovery of the BOK pathway provides great knowledge in

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expanding the understanding of intrinsic apoptotic signaling, as it provides a molecular basis and further detail for the extraordinary connection between ERAD PERK and apoptotic signaling. Additionally, it provides potential insight into the evolutionary history of apoptosis and its corresponding triggers, since many cases of apoptosis are often implicated (and logically so) to failed control of protein synthesis and folding [5]. Finally, considering the BOK-mediated apoptosis pathway is not limited by the many components (BH3-onlyprotein/BID) in play for the canonical intrinsic pathway, it provides an alternative route of inducing apoptosis unaffected by perturbation of such proteins. This is especially significant in the front of cancer development, in which upregulation of BCL-2 anti-apoptotic proteins are often correlated to [8]. Being unresponsive to BCL-2 anti-apoptotic protein, BOK-mediated apoptosis possesses great medical significance, as it holds great potential serving as a very attractive model for developing novel cancer-targeting therapeutics.

--Meng Lou REFERENCES

1.

Miyamoto, Shigeki. "Death Signaling 2." Biochem 630.

Madison. 21 Nov. 2016. Lecture.

2.

Llambi, Fabien, Yue-Ming Wang, Bernadette Victor, Mao Yang, Desiree M. Schneider, SĂŠbastien Gingras, Melissa J. Parsons, Janet H. Zheng, Scott A. Brown, StĂŠphane Pelletier, Tudor Moldoveanu, Taosheng Chen, and Douglas R. Green.

"BOK Is a Non-canonical BCL-2 Family Effector of Apoptosis Regulated by ER-Associated Degradation." Cell 165.2 (2016):

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421-33 3.

Hsu, S. Y., A. Kaipia, E. Mcgee, M. Lomeli, and A. J. W. Hsueh. "Bok Is a Pro-apoptotic Bcl-2 Protein with Restricted Expression in Reproductive Tissues and Heterodimerizes with Selective Anti-apoptotic Bcl-2 Family Members." Proceedings of the National Academy of Sciences 94.23 (1997): 12401-2406 4.

Ke, F., A. Voss, J. B. Kerr, L. A. O'reilly, L. Tai, N. Echeverry, P. Bouillet, A. Strasser, and T. Kaufmann. "BCL-2 Family Member BOK Is Widely Expressed but Its Loss Has Only Minimal Impact in Mice." Cell Death and Differentiation 20.1 (2012): 183 5.

Tsai, Y. C., and A. M. Weissman. "The Unfolded Protein Response, Degradation from the Endoplasmic Reticulum, and Cancer." Genes & Cancer 1.7 (2010): 764-78.

6.

Westphal, Dana, Grant Dewson, Peter E. Czabotar, and Ruth M. Kluck. "Molecular Biology of Bax and Bak Activation and Action." Biochimica Et Biophysica Acta (BBA) - Molecular Cell Research 1813.4 (2011): 521-31 7.

Luna-Vargas, Mark P.a., and Jerry Edward Chipuk.

"Physiological and Pharmacological Control of BAK, BAX, and Beyond." Trends in Cell Biology 26.12 (2016): 906-17 8.

Yip, K. W., and J. C. Reed. "Bcl-2 Family Proteins and Cancer." Oncogene 27.50 (2008): 6398-406.

// Quantum Physics

Beam Me Up, Scotty

Over the course of the 20th and 21st centuries, few technological advancements have captivated the science fiction imagination as much as teleportation. While far from achieving the capability of Captain Kirk’s transporter, quantum teleportation stands to have a practical impact on information transfer protocols including long-distance quantum communication and secure quantum networks.

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I

n 1993, C.H. Bennett and others published the first paper expounding the theoretical possibility of quantum teleportation and laid the groundwork for a decades-long process of achieving and refining such a quantum mechanical feat [1]. Based on John S. Bell’s seminal 1964 paper — written during his brief stint at the University of Wisconsin-Madison — quantum teleportation enables complete long distance information transfer through a combination of quantum measurement and operation and classical communication.

Unlike classical bits, quantum bits, or qubits, can exist in both

"Quantum teleportation enables complete

long distance information transfer through a combination of quantum measurement and operation and classical communication.

"

the usual 0 and 1 logic states as well as in a superposition of both 0 and 1 simultaneously. The four Bell states are maximally entangled qubit pairs in which information is contained exclusively in the pair: not all information can be known about either of the individual qubits. These maximally entangled states, also called Einstein-Podolsky-Rosen (EPR) pairs, are ironically both the basis of Einstein’s objections to quantum mechanics and Bell’s evidence for that same quantum mechanical nonlocality against which Einstein protested.

Einstein specifically objects to “spooky action at a distance,” which is the apparent violation of special relativity where a manipulation of one entangled particle generates a seemingly instantaneous reaction by the other, distant particle [2].

The canonical quantum teleportation protocol uses two parties, Alice and Bob, whose respective qubits A and B are prepared in a Bell state, one of four particular, maximally entangled states of two qubits. Alice also possesses a third qubit, initialized in an unknown state, which is the one that will be teleported to Bob. Akin to its science fiction analogue — where the transporter kills and recopies its user every time one is teleported — in order to teleport the particle, Alice must

perform a destructive Bell measurement (the original state cannot be preserved) on her qubit A and also the one that will be teleported, which is subsequently received by Bob. This Bell measurement reveals information about the entangled

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pair’s state but destroys its quantum mechanical nature. Furthermore, due to the entanglement of A and B, it also projects Bob’s qubit into a specific quantum state based upon the outcome of Alice’s measurement. Alice sends a classical two-bit message telling Bob the outcome of her measurement (this resolves the EPR paradox’s apparent violation of special relativity), after which Bob applies the proper local quantum logic operation on qubit B to recover the original unknown input state [1].

Free space teleportation over a lab bench (about one meter) was first achieved five years after Bennett’s theorization, when Furusawa et al. achieved a 58% fidelity transportation.

In quantum computing, fidelity is a measure of the degree to which the final state, in this case the teleported state, matches the ideal state expected as a result of the operations performed [3]. Since then, improvements have been made in free space teleportation, exemplified by a 2015 teleportation of over 16 m with an average fidelity of 89%. Using a teleportation scheme that calls for two particles instead of three, therefore allowing for a full Bell measurement, the experimenters exploited the theoretical possibility of perfect Bell measurements to achieve excellent fidelity [4].

This mention of the theoretical potential for perfect Bell measurements leads us to one significant practical limitation of quantum teleportation: the difficulty of fully distinguishing between the Bell states. As the current standard of Bell detection, using photodetection and linear optics, can only distinguish between two of the four Bell states, there is an upper limit for Bell measurement efficiency at 50%. In an effort to resolve the gap between theory – which states that with linear optics and n qubits one can approach 100% Bell-efficiency as n approaches infinity – and experiment, Hussain A. Zaidi and Peter Van Loock achieved over 60% unambiguous discrimination of Bell states. They did so with only linear optical elements, which never add frequency components or modify frequencies with respect to others in the system, and single-mode squeeze operators, which add pairs of photons, thus preserving the overall sign of the qubits’ spatial coordinates [5].

Teleportation over optical fiber, which stands to have perhaps the most immediate impact on communications networks, has especially suffered from these low detection efficiencies, where high photon loss and internal decoherence, or the destruction of stored quantum information, further limit

A quantum machine. The mechanical resonator is placed in a superposition, situated in the bottom left of the chip. The smaller white rectangle is the coupling capacitor between the mechanical resonator and the qubit.

Erik Lucero, Creative Commons

the maximum transmission possibility. In 2015, Takeuse et al. used superconducting nanowire single-photon detectors in order to teleport qubits over an astonishing 100 km of fiber [6].

Somewhat more practically, in 2016 another research group used a Calgary fiber network to teleport photons over 6.2 km [7]. As we move towards teleportation over many kilometers

"As we move towards teleportation over many kilometers with standard fiber, the reality of a quantum network becomes closer than ever."

with standard optical fiber, the reality of a quantum network becomes closer than ever.

Despite current practical limitations, recent research in both free space and optical fiber quantum teleportation has improved by orders of magnitude over early implementation efforts. With quantum computing capable of processing superpositions of logic states, these future networks offer the possibility for much higher efficiency computing over a distributed network, all relying on entangled photonic teleportation — that “spooky action at a distance”[7].

--Rose Walters

REFERENCES

1.

Bennett CH, Brassard G, Crépeau C, Jozsa R, Peres A, Wootters WK. Teleporting an Unknown Quantum State via Dual Classical and Einstein-Podolsky-Rosen Channels. Phys. Rev. Lett.

1993 March 29; 70 (13): 1895-899.

2.

Bell, JS. On the Einstein Podolsky Rosen Paradox. Physics.

1964 Novemebr 4; 1 (3): 195-200.

3.

Furusawa A, Sorensen JL, Braunstein SL, Fuchs CA, Kimble HJ, Polzik ES. Unconditional Quantum Teleportation.

Science. 1998 October 23; 282 (5389): 706-09.

4.

Jin X, Ren J, Yang B, Yi Z, Zhou F, Xu X, et al. Experimental Free-space Quantum Teleportation. Nature Photonics. 2010 May 16. 4 (6): 376-81.

5.

Zaidi HA, Van Loock P. Beating the One-Half Limit of Ancilla-Free Linear Optics Bell Measurements. Phys. Rev. Lett.

2013 January 15. 110 (26): 110.26 (2013): 260501.

6.

Takesue H, Dyer SD, Stevens MJ, Verma V, Mirin RP, Nam SW. Quantum Teleportation over 100 km of Fiber Using Highly Efficient Superconducting Nanowire Single-photon Detectors.

Optica. 2015. 2 (10): 832.

7.

Valivarthi R, Puigibert MG, Zhou Q, Aguilar GH, Verma VB, Marsili F, Shaw MD, Nam SW, Oblak D, Tittel W. Quantum Teleportation across a Metropolitan Fibre Network. Nature Photonics. 2016 September 19. 10 (10): 676-80.

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REPORT | Hyperoxia Affects the Expression of Mitochondrial Proteins UCP-3, SOD-1 and SOD-2

24

REPORTS

Many premature infants undergo aggressive oxygen and ventilator therapies to maintain oxygen saturation in under-developed lungs. Exposing rats to hyperoxia, an excess supply of oxygen, provides a well-accepted model for infants born prematurely who face these life-threatening circumstances. Here, I propose post-natal hyperoxia will decrease the expression of uncoupling protein-3 (UCP3) — a protein that affects energy metabolism in the skeletal muscle of newborns — and will increase the expression of superoxide dismutase-1 (SOD-1) and superoxide dismutase-2 (SOD-2) — enzymes that prevent damage from oxygen radicals. Rats were exposed to either hyperoxia (HYP) or normoxia (NORM) for 14 days. Oxygen exposure had no significant effect on the expression of SOD1. SOD-2 was found to be significantly lower in HYP rats compared to NORM rats. In addition, expression of UCP-3 among HYP rats was significantly lower compared to NORM rats. These findings suggest that high levels of post-natal oxygen lead to decreased expression of SOD-2 and UCP-3, which can lead to metabolic inefficiencies. If we are better able to understand the molecular impacts that premature birth has on infants, we can provide better care early on for these infants in order to decrease the risk of developing further pathologies in adulthood.

REVIEW | Who receives more? Using cognitive development to understand economic reasoning during resource allocation The economic field tends to assume rational agents for many mathematical models that explain strategic situations in our daily lives. The problem with these economic models is that they sometimes do not encapsulate the complexities of human behavior. In this review, I describe the results of the ultimatum game and the dictator game and provide alternative explanations based on psychological evidence for why the outcomes of these game theory games do not follow economic reasoning. To investigate why there is a discrepancy between the predicted and actual results of these games, we focus on developmental psychology and what research in the field can tell us about how cognitive processes, such as theory of mind, computing ratios, and determining reliability, develop. Theory of mind allows children to understand what other people are thinking and influences decisions regarding resource allocation. The ability to compute proportional ratios is advantageous for children when assessing equity among individuals. Determining reliability offers children a way to evaluate others during strategic tasks. By exploring human cognition’s effect on these specific strategic tasks in the context of development, we can better understand how competitive and cooperative decision making is not driven by achieving a mathematical equilibrium, but instead by developing cognitive processes that affect how choices are made.

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REPORT | Greater Parasitic Gregarine load in aquatic beetle larvae from polluted streams than pristine streams Human population growth and consumption have resulted in widespread pollution of tropical streams, yet, there are few studies examining the effects of pollution on aquatic invertebrates, which are often important bioindicators. Pollution severely impairs immune system function in a variety of organisms making them more susceptible to parasite colonization. Here, I examine the differences in colonization of Elmidae larvae by gregarine parasites in polluted and pristine stream environments. The stream habitat study sites were located in lower montane wet forest of Monteverde, Costa Rica. Twenty larvae were collected from two sites, both along the Quebrada Maquina. After larvae were collected, body length was measured and the peritrophic membrane of the gut was removed. Gregarine parasite abundance was determined by counting individuals after midgut staining. As expected by my hypothesis, individuals in the polluted environment had greater parasite abundance, greater numbers of parasites per cm of body length and were significantly smaller as larvae. This demonstrates that pollution is impacting gregarine parasite abundance in Elmidae beetles, specifically making hosts more susceptible to parasite infection.

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HYPEROXIA AFFECTS THE EXPRESSION OF MITOCHONDRIAL PROTEINS UCP-3, SOD-1 AND SOD-2 BY| MEGAN SHWARZ

ABSTRACT Many premature infants undergo aggressive oxygen and ventilator therapies to maintain oxygen saturation in underdeveloped lungs. Exposing rats to hyperoxia, an excess supply of oxygen, provides a well-accepted model for infants born prematurely who face these life-threatening circumstances [1]. Here, I propose post-natal hyperoxia will decrease the expression of uncoupling protein-3 (UCP-3) — a protein that affects energy metabolism in the skeletal muscle of newborns — and will increase the expression of superoxide dismutase-1 (SOD-1) and superoxide dismutase-2 (SOD-2) — enzymes that prevent damage from oxygen radicals. Rats were exposed to either hyperoxia (HYP) or normoxia (NORM) for 14 days.

Oxygen exposure had no significant effect on the expression of SOD-1. SOD-2 was found to be significantly lower in HYP rats compared to NORM rats. In addition, expression of UCP-3 among HYP rats was significantly lower compared to NORM rats.

These findings suggest that high levels of post-natal oxygen lead to decreased expression of SOD-2 and UCP-3, which can lead to metabolic inefficiencies. If we are better able to understand the molecular impacts that premature birth has on infants, we can provide better care early on for these infants in order to decrease the risk of developing further pathologies in adulthood.

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INTRODUCTION |

Conditions in the intrauterine environment and early postnatal life stages contribute to development of diseases later on in life, such as the development of hypertension, type 2 diabetes and heart disease [2]. Reduced insulin sensitivity, which can lead to the pathogenesis of these diseases, has been recognized in premature infants [2].

In a study conducted by Hovi et al. [3], adults who were born at term with normal birth weights (5 pounds, 8 ounces to 8 pounds,13 ounces) were tested for glucose tolerance and insulin sensitivity. Subjects who had a low birth weight had a 6.7% increase in fasting blood glucose, and an average increase of 40% in fasting insulin as compared to those who had normal birth weights, suggesting that adults who had a low birth weight had higher insulin resistance and lower glucose tolerance as compared to those who were born at term [3].

Premature infants face many challenges starting immediately after birth, including being born with immature lungs, weak breathing muscles and respiratory distress syndrome [4]. These issues can lead to hypoxia, a shortage of oxygen, which can damage other parts of the body. Although hypoxia is often treated by administering supplemental oxygen [5], it is difficult to safely administer oxygen therapies to infants because it can lead to lung damage. For instance, bronchopulmonary dysplasia (BPD), a type of chronic lung disease, can result from long-term use of oxygen, which some infants may never recover from [4]. In addition, supplemental oxygen therapies can lead to hyperoxia, an excess of oxygen in the lungs. Exposing neonates to hyperoxia can also overwhelm antioxidant defense mechanisms [5].

This impacts the function and expression of superoxide dismutase-1 (SOD-1) and superoxide dismutase-2 (SOD2 — enzymes that prevent damage from oxygen radicals.

SOD-1 is responsible for destroying oxygen radicals in the body and is thought to function primarily in the cytoplasm.

SOD-2 is responsible for forming diatomic oxygen from

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superoxide (O2-) in the electron transport chain and mainly affects superoxide in the mitochondria. [6]

Uncoupling protein-3 (UCP-3) is expressed in skeletal muscle and has been related to the risk of developing obesity and type 2 diabetes due to its role in the development of insulin resistance [7]. UCP-3 is associated with protection from insulin resistance and is important in separating oxidative phosphorylation from the synthesis of ATP in mitochondria [8]. In particular, UCP-3 is involved in lipid oxidation and has been shown to affect energy metabolism in the skeletal muscle of newborns [9]. It has been theorized that UCP-3 is able to export fatty acids that cannot be oxidized out of the mitochondrial matrix [10]. This function prevents these fatty acids from being built up in the mitochondria, reducing the risk of mitochondrial damage [10]. However, this energy conversion mechanism may not be sufficiently developed among premature infants, which could greatly impact metabolic processes [11], such as the accumulation of fatty acids in non-adipose tissues, like skeletal muscle, which is characteristic of diabetes [12]. Brauner et al. [9] took muscle samples from 40 low birth weight infants who had passed away and found a positive correlation between gestational age at birth and an increase in the expression of UCP-3. This data suggests that the length of intrauterine development has an impact on the expression of UCP-3, leading to insufficient development of key metabolic pathways and risk of disease if the time of intrauterine development is cut short via premature births [9].

The purpose of this study is to understand the presence of essential protective uncoupling and antioxidant proteins and the impact of oxygen therapy in premature infants. I decided to compare the difference in expression of UCP-3, SOD-1 and SOD-2 between rats that were either exposed to hyperoxia or normoxia for 14 days. I hypothesized that hyperoxia (HYP, 85% oxygen) would decrease the expression of UCP-3 expression and increase the expression of SOD-1 and SOD-2 compared to control

rats exposed to normoxia (NORM, 21% oxygen). The rats were constantly exposed to the different oxygen conditions in order to simulate the same conditions premature infants face because all term-born rats are born with the same stage of organ development as premature infants [1]. By using rats as our model organism, we can gain knowledge on the effects of premature birth in humans, and inform health care professionals providing care to premature infants. The results can help guide future studies regarding the risk factors associated with preterm birth to make progress toward changes in health care.

normalize the expression of the proteins. Vinculin is able to bind to the proteins so protein expression can be analyzed.

By standardizing the expression of the proteins by Vinculin, protein expression is able to be quantified. The membrane was washed three times in TBST again. Then using the Licor Odyssey CLx (LI-COR, 9140) near-infrared fluorescence imaging system, the blot was imaged with Image Studio.

Analyzing band density, the expression of UCP-3, SOD-1, and SOD-2 were quantified and compared between HYP rats and NORM rats using a two-way ANOVA with post hoc analysis by Tukey’s for multiple comparisons tests. A twoway ANOVA test was used to measure the effects of the two independent variables. Because the rats were separated into two groups — each with equal numbers of males and females with each group receiving a different oxygen treatment — the test is able to determine the relationship between the independent variables (gender and treatment type) and the dependent variable (expression of proteins). Tukey’s for multiple comparisons test is able to determine which means are statistically significant, where statistical significance is indicated by a p-value less than 0.05.

TABLE 1 | P-values from a two-way Anova multiple comparisons test on SOD-1, SOD-2 and UCP-3 using an alpha value of 0.05.

FIGURE 1 | Average values of SOD1 standardized by Vinculin.

FIGURE 2 | Average values of SOD2 standardized by Vinculin.

REPORTS

METHODS |

New-born Sprague Dawley rats were used for this study. Immediately after birth, 12 pups received constant exposure to hyperoxic gas (85% O2) and 12 pups received normal levels of oxygen (21% O2) to generate a control group for comparison. After 14 days of treatment, the rats were euthanized. Gastrocnemius muscle was harvested and flash frozen in liquid nitrogen.

Homogenized and protein isolated tissue was powderized in liquid nitrogen then lysed in a RIPA buffer with protease and phosphate inhibitors (ThermoFisher, 89900).

The protein was isolated and quantified with Bradford protein assay (Bio-Rad, 5000001) [12]. Protein samples were then aliquoted based on quantification and diluted with deionized water. Sample buffer and reducing agent were added to each sample of protein. Samples were heated at 95 degrees Celsius for five minutes. The Criterion XT gel (Bio-Rad, 3450120) was placed in the Criterion cell tank along with running buffer and each sample was loaded into the gel and run at 200 volts for 45 minutes. The gel was then transferred on to a nitrocellulose membrane (Bio-Rad, 1620112) and was run for 30 minutes at 100 volts. Proteins that were separated and then transferred on to the nitrocellulose membrane allow the protein expression to be analyzed. The membrane was then removed from the transfer tank and incubated in bovine serum albumin (BSA) (ThermoFisher, 15561020), and then in primary mouse anti-rabbit antibodies (SOD1, SOD2 and UCP3) (Cell Signaling, 3678S) at 4ºC [13] and then washed three times in TBST. Secondary infrared antibodies (infrared conjugated donkey anti-mouse (LI-COR, 68180) and donkey anti-rabbit (68073)) were added in solution with BSA in order to detect the protein, along with Vinculin (Abcam, 18058) to

RESULTS |

In a two-way ANOVA multiple comparisons test on SOD-1 expression, there was no statistically significant effect of hyperoxia on the expression of SOD-1 (p-value= 0.8481).

The mean value of SOD-1 expression shown in Figure 1, was similar in NORM males and HYP males. There was also no statistically significant difference between NORM females and HYP females (p-value= 0.9985), shown in Table 1.

However, by a two-way ANOVA analysis of SOD-

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2 expression, there was an overall statistically significant effect of hyperoxia on SOD-2 (p-value= 0.0016). Figure 2 shows that there was a significant difference in the mean SOD-2 value when comparing NORM males to HYP males (p-value= 0.0010). It also shows that there was a statistically significant difference in SOD-2 expression between NORM females and HYP females (0.0245).

A two-way ANOVA showed a statistically significant difference in gender (p-value= 0.02471) and treatment group (p-value= 0.0021) in the expression of UCP-3. Figure 3 highlights the difference in gender by showing the difference in average UCP-3 expression between HYP males (1.041) and NORM males (0.9280), as well as between HYP females (0.6988) and NORM females (0.7408). Table 1 shows that there was a statistically significant difference in UCP-3 expression between HYP males and HYP females (p-value= 0.0043), as well as NORM females and HYP females (p-value= 0.0240).

There was also a statistically significant difference between NORM males and HYP females (p-value= 0.0015). Analysis showed that there was no significant difference between HYP males and NORM males (p-value= 0.9875).

REPORTS

FIGURE 3 | Average values of UCP3 standardized by Vinculin.

DISCUSSION |

Expression of essential protective proteins in rats can serve as a model for infants who are born prematurely and require life-sustaining therapies because all term-born rats are born with the same stage of organ development as premature infants [1]. It was hypothesized that expression of UCP-3 would decrease with exposure to hyperoxia while expression of SOD-1 and SOD-2 would increase.

Although SOD-1 has been known to be responsible for the metabolism of cellular oxygen radicals, my data showed the expression of this enzyme was not significantly different, with the expression of SOD-1 remaining relatively unchanged between HYP and NORM rats. Despite the fact there was no significant difference in SOD-1 expression, there was a significant difference in SOD-2 expression between HYP and NORM rats. However, in both males and females, the expression of SOD-2 was less among HYP rats compared to NORM rats. SOD-2 is responsible for forming diatomic oxygen from superoxide produced by the electron transport chain during normal metabolism, preventing

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oxidative damage [6]. Thus, I would have expected SOD-2 expression to be higher in HYP rats. Further research needs to be conducted in order to confirm these results because lack in statistical significance could be due to procedural errors during Western Blotting. For example, during the transfer of the gel onto the membrane, not all of the air bubbles may have been rolled out, which may have caused the image of the blot to show these bubbles, making it difficult to quantify the expression of the enzymes and proteins. This lack of statistical significance could also be due to flaws in the theories of SOD-2 expression.

Gender played a significant role in expression of UCP-3. Analysis showed that UCP-3 expression was lower in females than in males. This could be due to the fact that females tend to have more slow-twitch muscle fibers than males, and studies have shown that fast-twitch muscle fibers contain higher levels of UCP-3 [14]. Future studies can be conducted to show that females do have a decreased need for UCP-3. There was also a significant impact of hyperoxia on UCP-3 expression. This relationship suggests that there is a negative correlation between the amount of oxygen given to the rats and the expression of UCP-3. Post-natal hyperoxia exposure in rats is a model for premature infants because, similar to rats, they are born with underdeveloped organs and then treated with high levels of oxygen. Thus, it can be rationalized that premature infants may have lower levels of UCP-3. This correlation shows the energy mechanism may not be fully developed in premature infants, which can impact several metabolic processes, including insulin resistance [8]. My results show that UCP-3 is significantly decreased among HYP rats, similar to premature infants. However, we need to further pursue the role of UCP-3 in the risk of development of metabolic disease in premature infants. Furthering our understanding of how oxygen therapy and other care neonates undergo may help reduce long-term complications. The incidence of type 2 diabetes of adults who were born prematurely has yet to be analyzed. Investigating this rate could lead to correlational research between UCP-3 and the development of insulin resistance [11].

In addition to more UCP-3 research, further research on the expression of SOD-1 and SOD-2 among rat models, as well as the expression of UCP-3 in fast-twitch compared to slow-twitch muscle, should be conducted in order to determine the relationship between gender and mitochondrial protein expression. Additional research on the effects of hyperoxia on organ development, also needs to be conducted. Those born prematurely face challenges not only immediately after birth, but later in life as well. Further research could lead to increased understanding of the care we provide to premature infants in order to reduce their risks for diseases, like type 2 diabetes and BPD, and increase their quality of life.

REPORTS

REFERENCES | 1. Brauner P, Kopecky P, Flachs P, Kuda O, Vorlicek J, Planickova L, Vitkova I, Andreelli F, Foretz M, Viollet B et al. . 2006. Expression of uncoupling protein 3 and GLUT4 gene in skeletal muscle of preterm newborns: Possible control by AMP-activated protein kinase.

Pediatric Research 60(5):569-575 2. Brun S, Carmona M, Mampel T, Vinas O, Giralt M, Iglesias R, Villarroya F. 1999. Activators of peroxisome proliferator-activated receptor-alpha induce the expression of the uncoupling protein-3 gene in skeletal muscle - A potential mechanism for the lipid intakedependent activation of uncoupling protein-3 gene expression at birth. Diabetes 48(6):1217-1222.

3. Chan C, Harper M. 2006. Uncoupling proteins: role in insulin resistance and insulin insufficiency. Curr Diabetes Rev 2(3):271-83.

4. Gien J. 2011. Pathogenesis and treatment of bronchopulmonary dysplasia. Curr Opin Pediatrics 23(3):305-13.

5. Hofman PL. 2004. Premature birth and later insulin resistance (vol 351, pg 2179, 2004). New England Journal of Medicine 351(27):2888-2888.

6. Hovi P, Andersson S, Eriksson JG, Jarvenpaa A-L, Strang-Karlsson S, Makitie O, Kajantie E. 2007. Glucose regulation in young adults with very low birth weight.

New England Journal of Medicine 356(20):2053-2063.

7. O'Reilly M, Thebaud B. 2014. Animal models of bronchopulmonary dysplasia. The term rat models. Am J Physiol Lung Cell Mol Physiol 307(12):L948-58.

8. Pedersen S. 2016. Insulin and Contraction Directly Stimulate UCP2 and UCP3 mRNA Expression in Rat Skeletal Muscle in Vitro.

9. Schrauwen P. 2002. Skeletal muscle uncoupling protein 3 (UCP3): mitochondrial uncoupling protein in search of a function. Curr Opin Clin Nutr Metab Care 5(3):26570.

10. Schrauwen P, Hesselink M. 2016. The role of uncoupling protein 3 in fatty acid metabolism: protection against lipotoxicity? Proceedings of the Nutrition Society 63(2):287-292.

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WHO RECEIVES MORE? USING COGNITIVE DEVELOPMENT TO UNDERSTAND ECONOMIC REASONING DURING RESOURCE ALLOCATION BY | CARLOS A. RAMIREZ

ABSTRACT The economic field tends to assume rational agents for many mathematical models that explain strategic situations in our daily lives. The problem with these economic models is that they sometimes do not encapsulate the complexities of human behavior. In this review, I describe the results of the ultimatum game and the dictator game and provide alternative explanations based on psychological evidence for why the outcomes of these game theory games do not follow economic reasoning. To investigate why there is a discrepancy between the predicted and actual results of these games, we focus on developmental psychology and what research in the field can tell us about how cognitive processes, such as theory of mind, computing ratios, and determining reliability, develop. Theory of mind allows children to understand what other people are thinking and influences decisions regarding resource allocation. The ability to compute proportional ratios is advantageous for children when assessing equity among individuals. Determining reliability offers children a way to evaluate others during strategic tasks. By exploring human cognition’s effect on these specific strategic tasks in the context of development, we can better understand how competitive and cooperative decision making is not driven by achieving a mathematical equilibrium, but instead by developing cognitive processes that affect how choices are made.

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INTRODUCTION | In the field of economics, it is often assumed in many models that all agents are rational. In economics terms, this means that people will think logically about the situation at hand and mathematically discover a solution that will be the most rational choice in regards to their self-interest. For example, if there were two identical watches for two different prices, a person would always pick the watch with the lowest price.

However, in many cases, agents are economically irrational; people make choices that may not be mathematically rational per se, but makes sense in the context of how they are feeling, the situation they are in, or how the specific circumstance is framed [1]. To use the previous example, if a person’s mother owned a watch store and sold the watch they wanted at a higher price than another store, the person would be more likely to buy his or her mother’s watch instead of the cheaper watch due to feelings of attachment for his or her mother. The field of behavioral economics has thoroughly investigated irrational agents and researchers use a blend of economics and psychology to understand how people behave in competitive environments. In this review, I will be focusing on economically irrational agents as a basis for understanding how individuals interact in strategic situations through certain cognitive abilities.

Competition is a key aspect of human behavior and one of the main scenarios where people can behave irrationally. A common concept that researchers use to analyze competitive behavior is game theory. Game theory is a branch of mathematics that provides models for intelligent beings in strategic situations and has had a major impact on fields such as economics, biology, and psychology. There are many different takeaways from game theory, but the one that is important for this review are two games that are provided from the concept: the ultimatum game and the dictator game. These games provide a powerful tool for psychological research since they provide a quantitative way of testing

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social situations among people in controlled environments [2].

The ultimatum game is a task in which two people, the proposer and the responder, are asked to allocate resources. An example of a resource is money. Let us assume the proposer receives one hundred dollars and the responder receives nothing. The proposer is asked to give whatever amount they choose to the responder. The proposer has the knowledge that if the responder does not deem the portion fair, then they can decline the offer and neither one of them keeps any of the money. Therefore, the proposer should offer the responder as little money as they will accept so that the responder does not decline the offer and the proposer receives something. According to economic theory, the responder should take any offer of money that is greater than zero since having something is better than having nothing. However, it has been shown in experiments that the proposer typically offers around 40% of the total resource and the responder rejects offers below 25% [3, 4]. The experiments show that human behavior in this scenario does not follow economic theory because the results of this game are not predicted by the theories provided by economists.

The dictator game is similar to the ultimatum game, but it takes away the responder’s power to deny an offer and does not punish the proposer for their inequity. The proposer, therefore, acts as the “dictator” in this task. An economically rational decision for the proposer would be to keep all the money and not give any to the responder. Despite this notion, it has been shown that offers from the proposer are normally around 28% of the total resource in the dictator game [5].

It is clear that there is a discrepancy between what economists would expect to happen during these games and what is observed. What is causing this discrepancy and can it be modeled with an interdisciplinary approach by using already researched psychological variables? Do humans only act in mathematically self-interested ways or do cognitive

determining reliability) to help investigate how previously thought irrational behaviors can be classified as rational.

THEORY OF MIND | ----Theory of mind is the ability to infer that other people have mental states apart from one’s own. This ability is often mastered when kids are between four and six years old and does not develop well in children with Autism Spectrum Disorder [7, 11]. Theory of mind is typically tested in children with a false belief task that requires them to think about different characters in a story [11]. The researcher asks the children what the characters’ thoughts are after an action is finished. For example, a researcher shows the child a story about Bob and Sue. Bob and Sue are sitting on a couch with a ball between them. Bob leaves the room and Sue hides the ball underneath the couch. The researcher then asks the child where Bob will look for the ball when he reenters the room. Children with developed theory of mind answer that Bob will look on the couch for the ball because this is where he last saw it. However, children with undeveloped theory of mind answer that Bob will look for the ball under the couch because the child, not Bob, knows the true location.

Children with undeveloped theory of mind lack the ability to see the situation as Bob sees it. Another test that can be used is a second-order false belief task, where the researcher asks the child where Sue thinks Bob believes the ball is. This type of task normally distinguishes those with strong theory of mind and weak theory of mind. Theory of mind can be very useful in situations where it can be beneficial to know what your counterpart is thinking.

Theory of mind can change the outcome of games such as the ultimatum game and the dictator game. It has been hypothesized that theory of mind is important because it can help the proposer avoid punishment [8]. Haruto Takagishi and his colleagues displayed the usefulness of theory of mind when they tested children around the age of five with the ultimatum game using candy as the resource.

In this task, a child would be given ten candies and then asked to distribute the candies between himself and another child. Takagishi and his colleagues found that children with theory of mind as tested by a false belief task, similar to the false belief task described earlier in this section, made fairer offers than those children who did not have theory of mind.

The authors concluded that if the proposer can predict how the responder would react to various offers, the proposer can make an appropriate allocation that will not elicit a negative response from the responder [8].

David Sally and Elisabeth Hill performed a similar test with the ultimatum game, but also included child participants with Autism Spectrum Disorder [7]. Sally and Hill instructed children to play the ultimatum game on the computer with a point system instead of a candy system.

The children would choose one of eleven cards on the screen with various options of how the points could be split.

A child at another computer would then accept or reject the offer and the points would be split per the rules of the game.

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processes make their behavior more complex and variable?

Although there have been many proposals put forward that support both of these possibilities, I will discuss how research in cognitive development can aid in investigating the notion that cognitive processes make human behavior complex and variable, which can be observed from a young age [1,6].

The main goal of this literature review is to lay the foundation for creating a logical model that both economists and psychologists can use to explain economically irrational behavior that will help in creating more accurate economic models and expand the definition of rationality. Economists typically call behavior that strays from economic models “irrational” because they do not have a consistent way to explain these types of actions and choices. Taking a developmental psychological approach to investigate the types of behaviors that cannot be explained by economic models can lead to more information about the type of cognitive tasks that occur during these behaviors [2]. Furthermore, understanding how cognitive abilities develop can aid the research community in helping predict how humans will behave throughout their lives and will be a useful aid in developing a model for irrational behavior.

How is irrational behavior during resource allocation related to cognitive abilities? When deciding how to allocate resources, individuals are often engaged in the task with another partner, requiring not only an understanding of the social consequences of a decision, but also how that decision will be made based on a mathematical computation that divides the resource between the individuals participating.

Given these requirements, this literature review focuses on three cognitive skills that develop during childhood that have implications for the social and mathematical aspects of resource allocation during the ultimatum and dictator games: theory of mind, computation of proportional ratios, and determining reliability.

Research on theory of mind, computation of proportional ratios, and reliability determination can provide information about the cognitive factors that go into making decisions during economic games. Theory of mind, the ability to recognize that somebody other than yourself has a mind and thoughts, has been shown to positively correlate with the fairness of children’s offers in the ultimatum game and the dictator game [7, 8]. The capability of children to compute proportional ratios may influence their inequity aversion, the distaste for unequal distributions, and could result in them making more even offers due to their inability to feel comfortable with unequal allocations of goods [9, 10].

Furthermore, the way children determine reliability is related to how they begin to trust other individuals and, therefore, may affect the way they behave in strategic situations. It is still not known how and when these cognitive abilities develop in children and what their implications towards economic theory can be. This review will analyze the ultimatum game and the dictator game and see how children interact with these game theory situations through focusing on specific cognitive factors (theory of mind, computation of proportional ratios, and

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The children would play sixteen rounds of the game and their roles as proposer and responder would be switched twice.

They concluded that younger children and children with ASD had a more difficult time making and accepting fairer offers [7]. Furthermore, there seemed to be a discrepancy between those who passed the first-order false belief task and secondorder false belief task. While the prior had the ability to make non-random decisions, the latter had a stronger tendency to be fair as seen in their offers. This trend demonstrates that the strength of a person’s theory of mind is positively correlated with his or her fairness.

Along with fairness, cooperation is an important aspect in the ultimatum and dictator games and having a theory of mind helps children cooperate more effectively.

When children are playing the ultimatum game, there is a need to cooperate since the proposer and responder both have the same goal of getting the most amount of money as possible and not losing it all with an unfair allocation. The proposer needs to be more generous than they normally would be if they want to make sure that the responder accepts the offer. Meanwhile, the responder needs to make sure what they receive is fair and can therefore determine whether they can both keep their money. Research has shown that children will often work together in these types of situations to get fair amounts of the good [12]. This can be hard to do without well-developed theory of mind skills since neither player would be able to determine what the other is thinking in this situation [7]. The proposer must especially think about how the responder would respond because it is up to the responder to decide whether they keep their allocations of money.

Furthermore, the proposer’s theory of mind abilities influence the outcome of the dictator game as well. Instead of giving the responder nothing, children tend to be more generous with their offers [7]. It goes against economic reasoning that children give any amount to the responder since the responder has no way of punishing the proposer if they view the allocation of money to be unfair. The proposer could be giving for external cooperation outside of the game to simply be more fair [12]. Overall, theory of mind may help children behave in a more cooperative manner since it allows them to mentalize other people’s thoughts.

As shown in the research, theory of mind has a significant impact on how children behave during tasks such as the ultimatum game and the dictator game [7,8]. There are many different scenarios in the real world that replicate these games and theory of mind could lead people to be economically irrational during these situations. For example, individuals with ASD would find it incredibly difficult to reach the optimal outcome of the ultimatum game because it may be difficult for them to know what the other person is thinking. Lacking theory of mind could also prove difficult in situations where it might be beneficial to be cooperative and understand the perspectives of those around you. A focus on research of atypically developing children could be beneficial in further investigating economic choices as it is shown that

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certain mental abilities, notably theory of mind, are required for making economically rational decisions. Furthermore, additional research could help map out a trajectory of how atypically developing individuals behave during certain economic situations and broaden models to incorporate humans of varying abilities. Since there is evidence to suggest the strength of one’s theory of mind can have an effect on their strategy in game theory games, future experiments could alter how well children know each other before the tasks and maybe even train them on theory of mind [7,8]. By connecting strategic game theory games to theory of mind, there are many implications of how this can be researched in the future.

COMPUTING PROPORTIONAL RATIOS |

Theory of mind is important when children need to evaluate what other children are thinking, such as when making decisions in game theory games. However, to make a proper decision, they also need to understand the basic element of what they are deciding: the fairness of the offer.

Adams defined fairness as having the same proportion of reward as the work put into the task [9]. Therefore, to understand what fairness is, a person must assess how much individuals have contributed and how to distribute a proportional reward based on that information. There are numerous theories that indicate that fairness is how people assess equity. For example, Adams suggests that people are uncomfortable with inequity and thus experience “inequity aversion”, which lead people to become more equitable as to avoid unpleasant feelings [9]. It is important to see the origins of this behavior by investigating whether children have the mental capacity to process two different kinds of information and act equitable.

To examine how the amount of work distributed between children affects how children allocate resources, Hook and Cook reviewed research measuring how children behaved in allocation tasks [10]. Allocation tasks are situations where researchers describe how much work other children are doing while assigning work to the child they are conversing with. With this knowledge, children are asked to allocate the reward between themselves and another child. Hook and Cook suggest that children go through certain stages of equity as they develop and only reach proportionality with their fairness when they are older [10]. The authors describe four types of allocation behavior: self-interest, equality, ordinal equity, and proportional equity. Self-interest is simply doing what is best for oneself by optimizing the amount that one receives in a situation where there is choice. Equality is defined as allocating resources equally among all participants. Ordinal equity is when someone is given a larger amount of reward for doing more work than someone else, but the reward is not necessarily proportional to the amount of work they did. For example, if Katie painted five birdhouses and Sam only two, then Katie might receive four of the seven candies. Proportional equity is when the ratio of the work one does equals the ratio of the

and reveal important findings in the fields of developmental psychology and economics.

When children grow older, their inequity aversion and ability to compute proportional ratios leads them to create allocations that are equitable and fair; however, people of different backgrounds and cultures could view fairness in different ways. Some cultures may view a larger reward to an elderly person as common sense even if they did less work than a younger person whom which they are sharing the reward. In fact, one study demonstrates that a child’s selfinterest in fairness and distribution can vary depending on what type of culture they are from (e.g. those with traditional cultures in small urban areas are less self-interested) [14].

Another study has shown that there are some similarities in the development of cognitive skills that have impacts on allocation and distribution [15]. Whether the definition of equity is found consistent or inconsistent, it is clear that there are certain cognitive abilities that change the way people allocate resources. The ability to assess what people have contributed to an operation and dividing resources according to those contributions are the two variables that a child has to maintain in their mind. Furthermore, the relationships between these two variables must also be processed, which can be difficult for younger kids. Hook and Cook categorize these logical mathematical skills and what can be expected when kids obtain them [10]. This is useful when trying to map a trajectory on how humans will behave in game theory game scenarios, especially the ultimatum game.

The economic view of fairness is often static and focused on the individual’s needs. Normally this assumption leads researchers to believe that humans are inherently selfish and will not give unless their outcome is better if they did give. Through proportional reasoning and inequity aversion, we can see that this is not the case. Although one could argue that feeling uncomfortable with inequity is enough of an economic reason to give, it can also be argued that the underlying concept of fairness is key and leads humans to act economically irrationally. As illustrated in this review, it is clear that humans develop definitions of equity in stages and that acting completely selfishly is not the only outcome in sharing scenarios.

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reward they receive. Using our example from before, Katie would get five of the seven candies and Sam would get two candies since there is a one-to-one ratio between work and reward. Hook and Cook found that children under six years old acted either completely self-interested or equally when distributing resources; whereas children between six years old and thirteen years old understood ordinal equity and even displayed some inequity aversion when they are around nine years of age. When children are thirteen years or older, they understand inequity aversion and behave proportionally equitable. This type of understanding demonstrates that children understand what fair ratios are beginning at age six, but do not know exactly what is fair until the age of thirteen.

The developmental trajectory of understanding proportional equity mirrors the more general ability of understanding proportional relationships. Hook and Cook [10] also reviewed the literature that assesses how children compare dimensions or stimuli based on distance and time.

In the Piaget study (as cited in [10]), Piaget moves two objects together, A and B, with one moving farther than the other and asked the children after the demonstration which object moved faster [13]. Results indicated that seven to nine-yearolds could not solve the problem, ten to eleven-year-olds could solve the problem but did not understand the relationship between distance and time, and twelve to fourteen-year-olds could solve the problem, and understood that the object that moved farther in the same amount of time also moved faster.

Hook and Cook found that the development of this ability mirrors the shift to proportional equity [10]. They suggested that at the core of fairness is the ability to process multiple kinds of information. The fundamental ability here is being able to keep track of two different variables at once and then draw a conclusion by observing their relationship. Children have difficulty retaining this information, processing it, and formulating an answer. However, it is seen here that their cognitive abilities are not dependent on the situation one is in, but are truly applicable to many situations and inherently influence one’s thinking.

Using the ability to retain multiple pieces of information, children strategize differently during game theory games. Hook and Cook suggest that children at different ages can conserve varying amounts of information which influence their decisions when sharing with others [10]. In the ultimatum game and the dictator game, both children have done the same amount of work and deserve the same amount of reward [9]. Therefore, anything other than an equal split between the children would be deemed as unfair. Given the properties of these games, it is hard to test whether children consider the amount of work one is doing when allocating the rewards. A plausible experiment to test this would be to tell the children that one child is more deserving of the reward than the other. This could be done verbally (e.g. tell the child “she helped clean more today than you”) or as an action (e.g. have the kids perform a task in which one child does more work) before the game is played.

Overall, these games help put these cognitive skills in action

RELIABILITY |

An additional factor to consider when investigating how children play game theory games is how they determine the reliability of the person they are interacting with. In this review, reliability will be defined as being able to trust that the other person will do what is predicted they will do. It is important to be reliable in situations of strategy and cooperation because being unreliable makes it hard to predict what will happen in the future. It is also a valuable skill to be able to know when someone is reliable so that the best possible strategy can be made for oneself.

Reliability affects how children play game theory games because being able to determine trustworthiness can change the outcome. Gummerum and colleagues

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discovered that pregame communication can positively affect cooperation between the players [2]. Communication could lead to further understanding and trust in games such as the ultimatum game which could lead to more generous offers or more lenient acceptances of proposals. The literature on people communicating before they play the ultimatum game is not abundant. In one study, the researchers asked teachers to rate how well a child knew their partner with whom they played the ultimatum game [8]. The researchers did not find a link between how well children knew their partner and how fair their offers were. However, it is not clear if teachers’ assessments of children’s relationships is a good indicator of how friendly and communicative children would be with their partners. In future work, it would be useful to directly manipulate children’s communication with and knowledge of their partner to identify developmental trends in how they trust in competitive situations.

In another study, Koenig and Harris tested the ability of children to determine trustworthiness of individuals in three experiments where a video clip of actors would point at objects and say what they were [16].

In each experiment, a different introduction procedure would be used to frame the actors and objects in the video in a different way. The researchers found that there were certain tasks that children can and cannot do at certain ages.

Specifically, it was found that three-year-olds cannot figure out who to trust in the future, while four-year-olds can.

Furthermore, it was found that three and four-year-olds can both distinguish between knowledgeable informants and ignorant informants as well as detect verbal and nonverbal cues to determine trustworthiness. These results suggest that children can perceive others as trustworthy from around age four, which shows that there is potential that the perceived trustworthiness of an individual can affect the outcome of game theory games. For example, if one person deemed their counterpart untrustworthy in the prisoner’s dilemma game, a game where working together can lead to the best outcome for both players, they might choose to act selfishly rather than cooperate. Or, in the ultimatum game, if the proposer deems the responder unreliable, then they might pursue a bigger or smaller offer depending on how they are feeling.

Reliability and trustworthiness have been demonstrated to be influential factors in understanding how children interact during game theory games. Since people are constantly analyzing whether others can be trusted, an ability which children also have, one might wonder what the implications are during these tasks. Future studies could look into how economics can model reliability and trustworthiness as they affect how people behave in a strategic world.

CONCLUSION | The purpose of this review was to close the gap between what economists deem rational and irrational by reviewing the literature in developmental psychological research.

By investigating children and how their cognitive abilities develop, both economists and psychologists can better predict how adults behave in strategic situations. Theory of

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mind is a key factor in how fair children will be when sharing resources because they understand what other children are thinking. The ability to compute proportional ratios give children the ability to decide equity when allocating reward between children who have done varying amounts of work.

Determining reliability and trustworthiness have implications in how children behave during strategic tasks theoretically, although more research on this should be explored.

This review has implications in how rationality is formed in people from a young age. By exploring cognitive abilities and how these abilities develop, one can examine behavior during game theory games in a different light. Instead of viewing humans as completely self-interested beings looking for a mathematical equilibrium, one can describe them as complex entities who take into account multiple different variables before making a strategic decision. While many economic conclusions derived from game theory have powerful utility to many fields of study, one must consider cognitive abilities as well as human behavior is intricate. Overall, the literature suggests that cognitive behaviors influence economic decision making and taking developmental psychology research into consideration might be helpful when trying to understand irrational choices.

ACKNOWLEDGEMENTS | The author would like to thank Dr. Viridiana Benitez for mentorship and guidance and Prof. Jenny Saffran for continuous support and supervision.

REFERENCES | 1. Tversky A, Kahneman D. The framing of decisions and the psychology of choice. InEnvironmental Impact Assessment, Technology Assessment, and Risk Analysis 1985 (pp. 107-129). Springer Berlin Heidelberg.

2. Gummerum M, Hanoch Y, Keller M. When child development meets economic game theory: An interdisciplinary approach to investigating social development. Human Development. 2008 Oct 3; 51(4): 235-61.

3. Oosterbeek H, Sloof R, Van De Kuilen G. Cultural differences in ultimatum game experiments: Evidence from a meta-analysis. Experimental Economics. 2004 Jun 1; 7(2): 171-88.

4. Fehr E, Fischbacher U. The nature of human altruism.

Nature. 2003 Oct 23; 425(6960): 785-91.

5. Engel C. Dictator games: a meta study. Experimental Economics. 2011 Nov 1; 14(4): 583-610.

6. Miller DT. The norm of self-interest. American Psychologist. 1999 Dec; 54(12): 1053.

7. Sally D, Hill E. The development of interpersonal strategy: Autism, theory-of-mind, cooperation and fairness. Journal of economic psychology. 2006 Feb 28; 27(1): 73-97.

8. Takagishi H, Kameshima S, Schug J, Koizumi M, Yamagishi T. Theory of mind enhances preference for fairness. Journal of experimental child psychology. 2010 Feb 28; 105(1): 130-7.

9. Adams JS. Inequity in social exchange. Advances in experimental social psychology. 1965 Dec 31; 2: 267-

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10. Hook JG, Cook TD. Equity theory and the cognitive ability of children. Psychological Bulletin. 1979 May; 86(3): 429.

11. Wimmer H, Perner J. Beliefs about beliefs: Representation and constraining function of wrong beliefs in young children's understanding of deception. Cognition. 1983 Jan 31; 13(1): 103-28.

12. Blake PR, McAuliffe K, Warneken F. The developmental origins of fairness: The knowledge–behavior gap. Trends in Cognitive Sciences. 2014 Nov 30; 18(11): 559-61.

13. Piaget J. The child’s conception of movement and speed.

New York: Basic Books; 1970.

14. Rochat P et al. Fairness in distributive justice by 3-and 5-year-olds across seven cultures. Journal of CrossCultural Psychology. 2009 May; 40(3): 416-42.

15. Callaghan T et al. Synchrony in the onset of mental-state reasoning: Evidence from five cultures. Psychological Science. 2005 May; 16(5): 378-84.

16. Koenig MA, Harris PL. Preschoolers mistrust ignorant and inaccurate speakers. Child development. 2005 Nov 1; 76(6): 1261-77.

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GREATER PARASITIC GREGARINE LOAD IN AQUATIC BEETLE LARVAE FROM POLLUTED STREAMS THAN PRISTINE STREAMS BY | SARAH DI BARTOLOMEO

ABSTRACT Human population growth and consumption have resulted in widespread pollution of tropical streams, yet, there are few studies examining the effects of pollution on aquatic invertebrates, which are often important bioindicators. Pollution severely impairs immune system function in a variety of organisms making them more susceptible to parasite colonization. Here, I examine the differences in colonization of Elmidae larvae by gregarine parasites in polluted and pristine stream environments.

The stream habitat study sites were located in lower montane wet forest of Monteverde, Costa Rica. Twenty larvae were collected from two sites, both along the Quebrada Maquina. After larvae were collected, body length was measured and the peritrophic membrane of the gut was removed. Gregarine parasite abundance was determined by counting individuals after midgut staining. As expected by my hypothesis, individuals in the polluted environment had greater parasite abundance, greater numbers of parasites per cm of body length and were significantly smaller as larvae. This demonstrates that pollution is impacting gregarine parasite abundance in Elmidae beetles, specifically making hosts more susceptible to parasite infection.

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INTRODUCTION |

Human domination in the Anthropocene has had profound effects on Earth’s ecosystems and biodiversity [1]. This has resulted in extinction rates 100 to 1000 times greater than pre-human levels [2]. More specifically, unrestrained human growth and consumption have resulted in increased human impact on freshwater systems for irrigation, hydroelectric power, and flood control [3]. These anthropological impacts have had unparalleled effects on tropical stream ecosystems causing declines in biodiversity [4] and disruption of important ecological process like nutrient cycling, primary production, and decomposition [5].

Streams in highly populated areas that are subject to surfactant chemicals and wastewater dumping have higher concentrations of inorganic compounds and lower oxygen concentration, which places a large stress on stream communities [6]. Pollution often results in cover of the substrata, sediment on the bottom of a stream, reducing available space for stream organisms [7]. This pollution causes changes in biotic communities and species interactions, altering fragile stream ecosystems [5]; however, the full extent to which ecosystem structure is affected by anthropogenic disturbances remains largely unknown [8].

In many ecosystems, including streams, perturbations in structure and function (e.g. pollution) impact parasite transmission and abundance [9]. Polluted environments severely impair immune system function in a variety of host organisms [10]. Protozoan parasites, including gregarines, take advantage of the hosts’ compromised immune system and increase in colonization when under ecosystem stress [9]. Typically, parasite species are most abundant at moderate pollution levels suggesting that they may serve as good indicators for earlier detection of unwanted environmental effects [11].

Because of this, parasite populations may serve as powerful bioindicators of environmental stress [9]. Parasites can affect host fitness behaviorally, physiologically, or morphologically [9]. This has been observed in a variety of species throughout the animal kingdom. Previous studies

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examining parasite colonization of chub communities in various levels of polluted environments found greatest parasite richness in polluted rivers when comparing to pristine habitats and environments with signs of pollution [11]. Pollution also impacts parasite abundance of smaller organisms that are vital to stream ecosystems. Gut fungal parasite abundance of lotic black fly larvae was found to be in greater abundance in individuals from polluted streams than pristine [12].

Gregarine parasites (phylum Apicomplexa, class Conoidasida, subclass Gregarinasina) are large single-cellular parasitic protozoa commonly found inhabiting aquatic insect hosts [13]. Hosts typically ingest gregarine oocysts containing infective sporozoites [14] which then attach and penetrate the hosts’ intestinal cells or reproductive system [15]. Adults and larvae of family Elmidae (riffle beetles) are known hosts of gregarine parasites [16]. For the purposes of this study, it was assumed that gregarine parasites affect hosts similarly to other parasites. Elmidae is also particularly

FIGURE 2 | Dissection process for the removal of the peritrophic membrane of Elmidae larvae. (a). General external anatomy of Elmidae larvae with labeled abdominal segments. (b) Removal of midgut from inferior end of larvae abdomen. (c) Peritrophic membrane stained with Giemsa after feces content removal. (d) Gregarine parasite found in peritrophic membrane of Elmidae larvae viewed at 400x magnification.

FIGURE 1 | Maps of polluted and pristine collection sites. (a). Overhead map of collection sites. The pristine sampling site is denoted by I and the polluted sampling site is II. (b). Topographical map, pristine sampling site denoted by I and polluted sampling by II.

METHODS |

Study site | Elmidae larvae were collected from two sites in Lower Montane Wet Forest in Monteverde, Puntarenas, Costa Rica (Holdridge life zone). The first collection site (pristine) was an undisturbed stream habitat along the Quebrada Maquina at the Monteverde Biological Station at 1535 m in elevation (Fig. 1). The second collection site (polluted) was further downstream of the Quebrada Maquina, at an elevation of 1450 m, which experiences dumping of organics and other waste from residential areas

(Fig. 1). Sites were chosen as there was access off lightly used trail.

Larval collection | Larvae from the pristine habitat were collected every 3 days beginning April 16, 2016 and concluding April 30, 2016 for a total of 5 days. Larvae from the polluted habitat were collected every 3 days beginning April 26, 2016 and concluding May 3, 2016 for a total of 4 days.

Sampling was performed until 20 successful individuals were dissected from each site. All samples were obtained along a 20 m stretch of stream. At each site, a dip net was placed vertically into the substrate at the bottom of the stream.

Rocks and sand were disturbed in front of the net and were collected into the net. Contents of the net were placed onto a white tray for examination and identification of Elmidae.

Using tweezers, larvae were placed into jars containing 80 percent alcohol. Larvae were all dissected within 72 hours of capture and, if necessary, were refrigerated overnight to preserve the peritrophic membrane, a semi-permeable structure that forms the midgut of the larvae.

Dissection and Microscopy | Larvae were measured length-wise to the nearest hundredth of a centimeter under an Olympus CX22 dissecting microscope using a centimeter ruler. Body length was measured to approximate the length of gut. After measurement, a larva was placed in a Petri dish with a small pool of water containing a few drops of 1:4 dilution of Giemsa stain and buffer. Giemsa stain is commonly used to stain blood and bone marrow cells, as well as protozoan blood parasites. Using dissecting scissors, the ninth segment of the abdomen was removed to free the inferior end of peritrophic membrane of the midgut (Fig. 2a).

The head was then removed from the prothorax using a pin.

This served to separate the superior end of the midgut from the pharyngeal muscles. Using tweezers, the eighth segment

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sensitive to the degradation of streams and found at greater abundances in pristine habitats [17]. This ability to react to stream quality reflects their ability as bioindicators due to a chance in parasite abundance depending on stream quality.

Bioindicators are species that reflect the abiotic or biotic state of environment as well as serve to represent the impact of environmental change of an ecosystem [18]. Elmidae larvae, found most often in well-aerated streams [19], contribute greatly to stream ecosystems by feeding on wood and creating highly grooved and sculptured surfaces [20]. These spatially complex surfaces support diverse invertebrate communities [20].

To the best of my knowledge, there are no previous studies examining Elmidae and their response to anthropogenic impacts in the tropics. The purpose of this study is to determine whether Elmidae larvae have the potential to serve as bioindicators indicative of stream pollution. Here, I examine the difference in colonization of Elmidae larvae by gregarine parasites in polluted and pristine tropical stream environments. Based on previous studies, I hypothesize that individuals from polluted environments will have greater gregarine parasitic load, greater density of gregarine parasites as well as shorter body length, than individuals of pristine stream environments.

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FIGURE 3 | Gregarine parasites in the midgut of Elmidae hosts in pristine and polluted stream environments of Lower Montane Wet Forest of Monteverde, Puntarenas, Costa Rica. Polluted stream larvae possessed greater gregarine abundance than those of pristine stream habitat. Means are based on 20 individuals from each habitat. Error bars represent +/- standard error.

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of the abdomen was then squeezed to push the midgut out of the inferior end (Fig. 2b). Once a sufficient portion of the peritrophic membrane was visible, the midgut was removed by carefully grasping the end and pulling away from the abdomen. Following complete removal of the midgut, tweezers were squeezed along the membrane to completely clear the gut of feces content. This was also accomplished by gripping one end of the membrane with tweezers and repeatedly lifting out of a small pool of distilled water. The membrane was then colored with 1:4 dilution of Giemsa stain (Fig. 2c). After coloring, each larvae membrane was wet mounted and examined with an Olympus CX22 compound microscope at 400x magnification. Total number of gregarine individuals were counted and recorded for each larva midgut (Fig. 2d).

Statistical Tests| Statistic values are reported with mean and standard error. Unpaired Student’s t-tests were performed to analyze the comparison of individuals from the two sites. Analysis of covariance (ANCOVA) was conducted to determine if there was a significant difference between the number of gregarine parasites based on body length when controlling for habitat. All tests were performed in R and P<0.05 was regarded as significant.

RESULTS |

Twenty larvae were collected from each habitat: pristine and polluted. Individuals from the pristine habitat ranged in body length from 1.1 – 1.4 cm and hosted between 0 – 7 gregarine parasites. Individuals from the polluted habitat ranged in body length from 0.7 – 1.25 cm and hosted between 1 – 7 gregarines. To the best of my knowledge, all gregarine parasites belonged to the same species as they were morphologically similar and found inhabiting Elmidae midguts. The mean number of gregarine parasites counted on the peritrophic membrane of Elmidae larvae from polluted stream habitat (3.8 ± 0.4 SE individuals) was, on average, 33 percent higher than individuals collected from pristine

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FIGURE 4 | Gregarine number in the midgut of Elmidae hosts in pristine and polluted stream habitats of Lower Montane Wet Forest of Monteverde, Puntarenas, Costa Rica per centimeter of body length. Polluted stream larvae hosted greater abundance of gregarine per centimeter of body length than those of pristine stream habitat. Means are based on 20 individuals from each habitat. Error bars represent +/- 1 standard error.

habitat (2.55 ± 0.36 SE individuals; independent t-test, p = 0.026, t = 2.32, df = 37.6, n = 20 larvae/site; Fig. 3).

The mean number of gregarines counted on the peritrophic membrane of Elmidae larvae, adjusted by gut length, from polluted environments (3.57 ± 0.36 SE individuals/cm) were, on average, 45 percent higher than those from pristine habitat (1.97 ± 0.4 SE individuals/cm; independent t-test, p = 0.003, t = 3.18, df = 35.6, n = 20 larvae/site; Fig. 4).

Elmidae larvae displayed a significant difference in body length between pristine and polluted habitats (independent t-test, p < 0.001, t = 5.3265, df = 32.769, n = 20 larvae/site).

Individuals collected from pristine habitats (1.28 ± 0.02 SE cm) were, on average, 15 percent longer than individuals of

FIGURE 5 | Body length of Elmidae individuals in pristine and polluted streams of Lower Montane Wet Forest of Monteverde, Puntarenas, Costa Rica. Body length in centimeters was greater for individuals of pristine stream habitat than those from polluted areas. Means are based on 20 individuals from each habitat. Error bars represent +/- 1 standard error.

polluted environments (1.1 ± 0.03 SE cm; Fig. 5).

An ANCOVA was conducted to determine if there was a significant difference between the number of gregarine parasites based on body length when controlling for habitat.

It was determined that the number of gregarine parasites did not increase in proportion with increasing body length for either habitat (ANCOVA, F = 0.20, df = 1, p = 0.20, n = 20 larvae/site, Fig. 6).

FIGURE 6 | Effect of body length on gregarine count in the gut of Elmidae larvae of pristine and polluted stream sites in Lower Montane Wet Forest of Monteverde, Puntarenas, Costa Rica. Gregarine number did not increase with body length for the pristine or polluted stream habitats. Pristine and polluted samples are each represented by 20 individuals. Each point represents one individual sampled.

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DISCUSSION | This study demonstrated, consistent with my hypothesis, that gregarine parasites are more abundant in Elmidae hosts from polluted stream environments than those from pristine environments as found in previous studies with different host organisms. It was also demonstrated that gregarine infestation per centimeter of body length increased significantly in more polluted habitats when compared to pristine inhabiting individuals. Unsurprisingly, also consistent with my hypothesis, larvae from the polluted habitat were significantly shorter than those from pristine habitat.

These results clearly demonstrate that stream pollution is correlated with increased level of gregarine infestation of Elmidae midguts. Previous studies evaluating intestinal parasites of fish found that toxin exposure increases parasite burden [21]. It is often found that parasites, like gregarines, with direct life cycles increase in abundance in contaminated habitats [21]. Parasites with direct life cycles infect their host without an intermediate host where they reproduce and complete their entire life cycle. This is supported by the fact that pollution compromises host immune systems increasing susceptibility to parasite loads in a variety of organisms [9]. Another possible explanation is the â&#x20AC;&#x153;density-dependent prophylaxis hypothesisâ&#x20AC;? which states that as host densities increase and are more exposed to infective stages of parasites because of larger population sizes, hosts allocate more energy towards parasite resistance, making them less susceptible [22]. Studies on Oriental armyworm moth (Mythimna separata) larvae found that virus-induced mortality declined from 95 percent for insects

reared solitarily to 37 percent for insects reared at the highest density [23]. This idea could potentially be applied to parasite transmission. Thus, since Elmidae abundances are greater in pristine habitats, due to Elmidaeâ&#x20AC;&#x2122;s sensitivity to stream degradation, they will have greater resistance to parasite colonization in pristine habitats.

This study also shows that Elmidae larvae body length varied significantly between habitats with smaller individuals found inhabiting polluted stream habitats. While studies on Elmidae life cycles are somewhat lacking, it has been proposed that the larval cycle lasts one year with them hatching early summer which serves as a control for age [24].

Therefore, smaller individuals with higher gregarine loads were found in polluted environments. Gregarine infected individuals experience delayed development and decreased longevity, especially under environmentally stressful conditions [25]. Previous studies on earthworms (Lumbricus terrestris) determined that there was a significant negative relationship between parasite load and growth. Thus, parasite-mediated lower growth rate represents a fitness cost because mating success and choice is often correlated with size [26]. This connective nature between pollution, increased parasites and inhibition of growth demonstrates the potential overarching impacts on the ecological function of Elmidae.

While larvae were identified by family level characteristics, there was no reason to believe that genus or species level differences would result in different outcomes due to strong morphological similarities and similarities in substrate between individuals collected from both sites.

Therefore, there was no reason to believe the larvae were of different species despite my inability to classify them to species level.

In conclusion, elevated pollution levels are correlated with higher gregarine abundances in Elmidae hosts. This indicates that parasitism levels of Elmidae may serve as powerful bioindicators for stream water quality. Future studies sampling Elmidae from a range of stream qualities and determining if there is a correlation with parasitic load would shed light on Elmidae as an effective bioindicator.

Furthermore, the ecological impact of parasitized Elmidae larvae would help complete the overall ecological picture of anthropogenic impact. In order to determine, While the overall ecological impact of higher levels of parasitism in Elmidae is still yet well understood, this study demonstrates, consistent with my hypothesis, that pollution is impacting gregarine parasite abundance in Elmidae beetles, specifically making hosts more susceptible to parasite infection.

ACKNOWLEDGEMENTS | I would like to thank my advisor Dr. Johel Chaves for his continuous guidance throughout the research process.

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Thank you to Dr. Alan Masters for helping develop my project idea and Moncho Calderón for his continuous patience and support in developing my methods and general encouragement. I would also like to thank Madison Cox for her advice and answering any experimental design questions.

Finally, thank you to all CIEE staff and the Monteverde Biological Station for providing me with a field study site and facilities.

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JUST celebrates the unboxing of its inaugural Spring 2016 publication.

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JUST celebrates the unboxing of its inaugural Spring 2016 publication.

All images courtesy of creative commons (CC0) or Margaret Seybold.

We would like to sincerely thank CALS, the Office of the Dean of L&S, the Associated Students of Madison, and the Holtz Center for Science and Technology Studies for financially supporting the production of JUSTâ&#x20AC;&#x2122;s issue. Thank you!

Victoria Fok, WUD Publications Committee Director Jim Rogers, WUD Publications Committee Advisor Deshawn McKinney, Wisconsin Union President

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