YSM Issue 90.1

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Yale Scientific Magazine 

VOL. 90 ISSUE NO. 1 

CONTENTS 

DECEMBER 2016 

NEWS 6 

FEATURES 25 

ON THE COVER 

15 

STICKING IT 

TO CANCER 

Yale researchers demonstrate drug 

delivery efficacy via a bioadhesive 

class of nanoparticles designed for 

administering cancer treatment. 

12 

A ROCKY ROAD 

TO THE PAST 

Using new analytics to understand 

tiny mineral crystals, a Yale G&G team 

discovers evidence for the effect of 

volcanic activities on global climate. 

18 

CANINES ARE OVER 

OVERIMITATION 

A recent Yale study supports that 

overimitation is distinctly human, 

as dogs and dingoes are more 

inclined to evade irrelevant actions. 

20 

PERPLEXING FOSSILS 

& PECULIAR FORMS 

Researchers from Yale and other 

institutions unearth the origins of 

the Tully Monster, a Carboniferous 

creature with unusual morphology. 

“FEELING THE SURFACE TENSION” 

22 

EXPANDING QUANTUM 

COMPUTING 

Uniting quantum mechanics and 

computer science, Yale researchers 

make progress towards constructing 

more powerful quantum computers. 

More articles available online at www.yalescientific.org 

December 2016 


3

q a 

& 

CO 2 

Past the point of no return? 

►BY MATTHEW KEGLEY 

Climate change has been ranked a top 

global threat, with indicators such as carbon 

dioxide (CO 2 

) levels illustrating its 

rapid progression. Each year, CO 2 

levels 

are lowest in September—but this year, 

even at their annual minimum, CO 2 

levels 

stayed above 400 parts per million 

(ppm). Scientists consider 400 ppm to 

be the “fail-safe” ceiling for CO 2 

levels. 

Beyond this concentration means that 

Earth has permanently surpassed 350 

ppm, the highest level needed to maintain 

climate stability. So when the Mauna 

Loa Observatory, a global monitoring facility 

in Hawaii, discovered that CO 2 

levels 

remained unusually high this year, the 

news was concerning for many experts. 

“We won’t be seeing a monthly value 

below 400 ppm this year—or ever again 

for the indefinite future,” said Ralph 

Keeling, director of the Scripps Institute 

for Oceanography, after he analyzed the 

IMAGE COURTESY OF WIKIPEDIA COMMONS 

►Smoke is emitted from factory smokestacks 

beside a highway. 

daily Mauna Loa recordings. 

With global CO 2 

continuing to rise, 

has our atmosphere been irreversibly 

altered? Joshua Galperin, research 

scholar and lecturer in law at Yale Law 

School and the Yale School of Forestry 

and Environmental Studies as well as 

the director of the Environmental Protection 

Clinic, believes we can address 

the problem if both policymakers and 

citizens make changes. “[Policymakers] 

need to be imaginative,” Galperin said. 

Specifically, he promoted the elimination 

of coal power as a starting point 

for energy reformation. 

Galperin further suggested that citizens 

use their skills in economies “built 

on carbon” to ensure integrity as they 

retract from carbon. He also emphasized 

the need for hope at the forefront 

of our actions to combat climate 

change. 

Three’s a Crowd—How can a baby have three parents? 

►BY MILANA BOCHKUR DRATVER 

Modern technology has allowed for the 

creation of “three-parent” babies by incorporating 

genetic material from three individuals 

in the creation of a single embryo. 

For parents whose children are at risk of 

inheriting a mitochondrial disorder, genetic 

material from a third person can 

help them conceive a healthy child. Mitochondria 

are maternally inherited organelles, 

so if a mother’s mitochondrial DNA 

is mutated, her children are at risk of developing 

defects that frequently result in 

infant death. 

Researchers first attempted to prevent 

mitochondrial diseases in the 1990s by 

injecting mitochondrial DNA from a donor 

into another woman’s egg, along with 

sperm from her partner. Some of these 

children developed genetic disorders, and 

the US Food and Drug Administration 

stopped the procedure. 

IMAGE COURTESY OF WIKIPEDIA COMMONS 

►Sperm cells surround and fertilize a human 

egg as seen under a light microscope. 

A recently approved method now used 

in the United Kingdom is pronuclear 

transfer: the mother’s and a donor’s egg 

are fertilized with the father’s sperm, 

both nuclei are removed from their respective 

eggs, and the mother’s nucleus 

is transferred to the donor’s egg. The embryo 

then possesses mitochondrial DNA 

from the donor, as well as nuclear DNA 

from its parents. In this way, the child 

has genes from three different parents. 

Recent successful three-parent-births 

give hope to parents who have lost children 

to mitochondrial disorders. 

“Mitochondrial diseases were incurable 

until now. The opportunity to use 

mitochondrial replacement as a form of 

cell therapy to provide a ‘cure’ should be 

embraced,” explained Pasquale Patrizio, 

Director of Yale Fertility Center & Fertility 

Preservation Program.

3 

The year began with the thrilling discovery of gravitational waves. We said that 

was just the beginning, and indeed what a year it has been for science and for us 

at the Yale Scientific. From breakthroughs in cancer therapy in To Immunity and 

Beyond (89.2) to advances in quantum computing in Welcome to the Quantum Age 

(89.3) to new approaches to art restoration in Decko Gecko (89.4), it has been an 

absolute joy sharing these fascinating scientific stories with you, our readers. 

On this issue’s cover, we are excited to feature research conducted at Yale that 

harnesses nanotechnology to target drugs to cancer cells with greater potency and 

fewer side effects (pg. 15). Not to be outdone, another Yale team has discovered a 

new drug candidate for lung cancer that acts through a novel mechanism (pg. 8). 

Meanwhile, across the Pacific Ocean, a group of researchers in Melbourne are exploring 

a novel approach to treating antibiotic-resistant bacteria (pg. 30). 

This year also marks the 150th anniversary of the Yale Peabody Museum (pg. 25). 

Museums like the Peabody inspire awe with their remarkable collections of fossils 

and minerals. Easier to forget is the fascinating research that goes on behind the 

scenes. The intriguing tale of the Tully Monster, a fantastic creature that has finally 

been assigned its proper place in the tree of life, pays tribute to those efforts (pg. 20). 

In many ways, the past holds insights for the present. In this issue, we dive into 

the changes in carbon dioxide levels that have taken place across geologic time as 

volcanic activity rose and fell. What we see is troubling, with surging carbon dioxide 

levels driving a majority of species to extinction (pg. 12). As greenhouse gas levels 

continue to rise, we evaluate where we stand today (pg. 4) and report on the quest 

for cleaner sources of energy (pg. 10). 

We worry about the future of climate change research as a new administration 

takes over in January. Still, we take heart in the progress that scientists and engineers 

around the world have already made, and we remain quietly optimistic that 

scientists will respond to the increased urgency for clean-energy solutions with a 

wave of innovation. 

At our magazine, it is also time for us to pass on the baton to a new masthead. 

We are struck by their boundless energy and their refreshing ideas, and we have full 

confidence that they will carry this publication to greater heights. 

Thank you for reading these pages. It has been our privilege and pleasure. 



THE NATION’S OLDEST COLLEGE SCIENCE PUBLICATION 

DECEMBER 2016 VOL. 90 NO. 1 | $6.99 

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F R O M T H E E D I T O R 

A B O U T T H E A R T 

Lionel Jin 

Editor-in-Chief 

The cover, designed by arts editor Ashlyn Oakes, shows 

the artist’s interpretation of nanoparticles as they deliver 

drugs to cancerous endometrial cells. Endometrial cancer 

is resistant to many forms of chemotherapy and must 

be combated using powerful drugs which often have severe 

side-effects. In order to relieve some of those side 

effects and increase drug potency, Yale researchers have 

developed sticky nanoparticles that attach to the surface 

of tumor cells, delivering drugs in a targeted fashion to 

the tumor and promising safer, more effective treatments 

to a debilitating disease. 

Editor-in-Chief 

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NEWS 

in brief 

Modeling Mars: Life-Supporting Earthquakes? 

By Isa del Toro M. 

IMAGE COURTESY OF WIKIPEDIA 

►A topography map of Mars with different 

color intensities indicating the depth 

of craters and highlighting areas of possible 

seismic activity on its surface. 

There’s a new hypothesis on the block related 

to the possibility of life on Mars. Research 

conducted by Sean McMahon of the Yale Geology 

and Geophysics department, in collaboration 

with John Parnell and Nigel Blamey, 

looks into Earth’s subsurface hydrogen levels 

and how these indicate potential microbial 

activity on Mars. 

Hydrogen serves as an energy source for 

certain types of organisms. Subsurface hydrogen 

gas is created on Earth due to the grinding 

of rocks along ancient earthquake fault 

lines. McMahon’s experiment sought to determine 

whether these gas levels were enough 

to have spurred microbial life. Using crushfast-scan, 

a technique that involves crushing 

rocks to expel the gas contained with them 

and measuring the released gas composition, 

the researchers concluded that the hydrogen 

contained in these rocks was sufficient to fuel 

anaerobic life on Earth. Many types of rocks, 

including the basalt found on Mars, can likewise 

create hydrogen, leading researchers 

to determine that quake activity on Mars 

could fuel microbial life. In 2018, NASA’s 

InSight mission will collect data concerning 

seismological activity on Mars. This data 

will allow the researchers to re-evaluate the 

“Marsquake” models they used in their conclusions 

and determine whether their models 

fit Mars’s actual surface. 

McMahon’s results are an exciting find. 

They shed light on another possibility of life 

on Mars, which would have important consequences 

on how we approach the idea of human 

activity on the Red Planet, as well as our 

understanding of how life came to be in the 

universe. 

The Gruber Cosmology Conference at Yale 

By Urmila Chadayammuri 

PHOTOGRAPHY BY URMILA CHADAYAMMURI 

►Professor Manuela Campanelli of 

the University of Rochester presents 

her pioneering simulations of black 

hole mergers. 

The third annual Gruber Cosmology 

Conference took place at Yale on October 

7th, honoring discoveries advancing our 

understanding of the universe. This year’s 

Gruber Prize recipients were Rainer Weiss, 

Kip Thorne, and Ronald Drever, the leading 

scientists on the LIGO collaboration, which 

made the groundbreaking discovery of 

gravitational waves. The conference began 

with a history of gravitational waves, after 

which Weiss explained how the LIGO project 

worked. Speakers also highlighted upcoming 

detectors in Europe, India and Japan, which 

aim to pinpoint the origin of gravitational 

waves. 

The afternoon session outlined the impact 

of the discovery. Thorne described the 

new science we can probe with the help of 

gravitational waves, from learning about how 

the very early universe grew, to understanding 

spinning and colliding black holes. Harvard 

radio astronomer Shep Doeleman closed the 

conference with prospects for how we can 

directly image black holes and their power as 

gravitational lenses, which bend light from 

sources behind them, to directly image black 

holes. 

The presenters all spoke of their work as a 

conversation across centuries with the father 

of general relativity, Albert Einstein. What 

would Einstein have said if he heard of the 

LIGO observation? Thorne guessed he would 

try understanding the black hole merger that 

caused it, while Weiss thought he would ask 

how the equipment worked. Doeleman took 

a step back. We knew general relativity was 

correct before the gravitational wave detection, 

he said, as GPS would not work without it. If 

we were to present a map app to Einstein, he 

would most likely wonder, “What is a phone?” 

6 Yale Scientific Magazine December 2016 www.yalescientific.org

in brief 

NEWS 

The Miller laboratory of Yale’s Department 

of Chemistry recently made a discovery 

in peptide catalysis that could change how 

we think about enzymes. This discovery 

capitalized on the laboratory’s previous 

discovery of two peptide catalysts. Enzymes, 

or protein catalysts, are characterized by high 

specificity. Alford, the study’s first author, and 

his colleagues demonstrated that two short 

peptides, which are comprised of protein 

building block called amino acids, can catalyze 

two distinct, complementary reactions called 

oxidation reactions. This remarkable capacity 

is presumably due to the synthetic peptide’s 

overall structure: by varying just a few key 

amino acids outside of the active site where the 

reaction takes place, the same active residue can 

switch between catalyzing two very different 

reactions. This control of catalytic activity by 

Shrinking Enzymes 

By Giorgio Caturegli 

modifying secondary structure is a hallmark 

of enzymes but has had limited application 

in organic synthesis. “This finding is a really 

interesting manifestation of what the [Miller] 

group tries to do…using tools that nature has 

to understand natural processes,” said Nadia 

Abascal, a coauthor. Synthetic reactions can 

be studied to gain insight into processes in 

nature, which may follow a similar mechanism 

to the reactions observed in this study. 

Especially notable is the fact that peptides 

are orders of magnitude smaller than 

enzymes, and their small size and precise 

control could allow for synthetic applications 

in pharmaceutical and materials research. 

The Miller group’s recent finding in peptide 

catalysis is important to both understanding 

natural biochemical processes and developing 

synthetic applications. 

PHOTOGRAPHY BY NATALIA ZALIZNYAK 

►Miller’s laboratory discovered two 

peptides that can catalyze two different 

reactions based on secondary 

structure and reaction conditions. 

A New Excuse for Playing Video Games? 

By Jasper Feinberg 

Imagine if video games were a key to 

improving learning. Yale psychiatry professor 

Bruce Wexler believes they are. A study found 

that a video game-based learning regimen 

called Activate, developed by Wexler, improved 

the test performance of 583 schoolchildren 

compared to those without the regimen and 

those with one-on-one tutoring. The curriculum 

includes computer games aimed at cognitive 

improvement and a five minute warm-up 

computer activity designed to prepare students 

for learning. 

The Activate program harnesses 

neuroplasticity. The structure of the brain 

is shaped after birth from environmental 

stimuli that reorganize neuronal connections. 

Activate stimulates areas of the brain often 

underdeveloped in children who grow up in 

poverty or have neurodevelopmental problems 

like attention deficit hyperactivity disorder 

(ADHD). To accomplish this, Wexler used 

neuroimaging studies to identify the regions 

of the brain corresponding to certain cognitive 

tasks. Wexler describes Activate as “a school 

lunch program for the brain” customized to each 

individual student. 

The social implications of this educational 

strategy are vast. First, Activate has the potential 

to close the achievement gap by helping students 

with different educational backgrounds. As a 

technology-based tool, it is cheaper than many 

current solutions. Wexler’s research is also an 

effective treatment for depression and, in some 

cases, ADHD. 

Going forward, C8 Sciences, a Yale startup 

dedicated to spreading Activate, hopes to 

increase awareness and continue improving 

the program. Activate has been translated into 

multiple languages, and appears primed to 

expand. 

IMAGE COURTESY OF BRUCE WEXLER 

►A student using Activate, a gamebased 

learning program shown to 

improve test performance, in her 

school’s computer lab. 

www.yalescientific.org 

December 2016 


7

NEWS 

molecular biology 

BREATHE EASY 

New drug reduces lung cancer cell growth 

►BY EILEEN NORRIS 

Wouldn’t it be nice if killing lung cancer cells was as easy as 

flipping a switch? As it turns out, effectively targeting these 

cells is more like a dimmer rather than a switch, but it can 

be done, according to new research spearheaded by Joseph 

Contessa, associate professor of Therapeutic Radiology and 

Pharmacology at the Yale School of Medicine. Contessa led 

the discovery of a drug that reduces non-small cell lung cancer 

(NSCLC) tumor cell growth, proliferation, and survival, 

without causing toxic effects to healthy cells. 

NSCLC comprises about 80 to 85 percent of lung cancers and 

generally spreads more gradually than small cell lung cancer. 

Much cancer biology research surrounds the role of receptor 

tyrosine kinases (RTKs), cell surface receptor proteins, in the 

behavior of tumor cells. RTKs stimulate signals within cells 

that direct the cell to grow, divide, and proliferate, and can 

trigger survival signals in toxic environments. In cancer cells, 

RTK genes are overexpressed, causing more RTKs to appear 

on the cell surface, leading to more resilient and fastergrowing 

cancer cells. 

Contessa’s lab aimed to better understand how RTKs 

affect tumor growth and survival, and therefore explore how 

scientists can target these receptors to control tumors. Prior 

hypotheses extrapolate that if one can block the function of 

RTKs, turning them “off,” tumors can be treated with more 

success. Current drugs and compounds such as Gefitinib 

and Erlotinib target specific RTKs but do not work as well as 

hypotheses predict. Early in his research, Contessa postulated 

that these drugs failed due to redundant signaling, or the 

presence of dominant and backup receptors that all signal 

NSCLC tumor cell growth and proliferation. Therefore, 

drugs and compounds that only target one receptor are 

ineffective in treating the NSCLC tumor cells. 

Thus, Contessa looked for ways to target multiple 

receptors without creating a toxic environment for normal 

cells. He found that all of the receptors are glycoproteins— 

they have sugar chains attached to them. Contessa then 

hypothesized that by interrupting glycosylation—the 

addition of sugar chains—the function of the glycoprotein 

RTKs could be blocked. 

“What people thought before was that adding these sugar 

chains was a switch like a light switch, turning on and turning 

off. What we’ve shown is there’s actually a spot that you can 

hit it that’s more like a dimmer switch, where you can just 

turn it down. What we found is a small molecule, a drug-like 

compound, that can act this way—it can turn the dimmer 

switch down,” Contessa said. 

This drug, N-linked glycosylation inhibitor-1 (NGI- 

1), targets non-small cell lung cancer cells by inhibiting an 

enzyme that attaches sugar chains to RTK precursors and 

creates the mature glycoprotein RTKs. Contessa’s research 

showed that this drug reduces the expression of epidermal 

growth factor receptor (EGFR), a specific RTK, on the surface 

of the lung cell. In the drug-treated cells, the EGFRs were 

found inside of the cell, indicating that NGI-1 prevents the 

transport of RTKs to the cell surface. 

Contessa’s research further confirmed that NGI-1 is 

specific; although it inhibits RTK signaling, it does not 

inhibit the transport of all glycoproteins to the cell surface, so 

glycoproteins essential to healthy cell function are unaffected. 

“It means that tumor cells that are highly dependent on 

RTKs become very sensitive to this drug,” Contessa said. 

His research shows that NGI-1 arrests cellular growth and 

division in RTK-dependent NSCLC tumor cells. 

The project was not without difficulties. “The whole project 

was a challenge… it was a collaborative effort, and we worked 

with a couple different groups,” Contessa said. The process 

sounds easy—a step-by-step path towards a new method of 

battling lung cancer. In reality, this one drug resulted from 

five years of dedicated research and testing, screening over 

350,000 drugs. 

“You’re kind of on this detective hunt. You’re screening and 

you find this inhibitor, and then you don’t know exactly how 

it works. So you have to call on some expertise to help you, 

and then hopefully you get a little lucky and you figure out 

the mechanism and you can advance it to your experimental 

models,” Contessa reflected. 

Contessa’s detective mindset, along with the advice of 

many collaborators and a bit of luck, led the researchers 

to a potential drug candidate for battling NSCLC tumors. 

Contessa looks to translate their successes in laboratory cell 

models into successes in live animal tumor models, and we 

will hopefully see NGI-1 in future clinical studies. 

PHOTOGRAPHY BY JARED PERALTA 

►A member of Joseph Contessa’s lab at work at the Yale 

School of Medicine. 


computational biology 

NEWS 

SOLVING THE PROTEIN REPACKING PUZZLE 

Tinkering with the building blocks of life 

►BY KEVIN CHANG 


IMAGE COURTESY OF WIKIMEDIA COMMONS 

►Before the advent of computational methods, biologists 

and biochemists had to rely on bouncing x-rays off of protein 

crystals in order to determine the 3D structure of a protein. 

Proteins play an important role in all life processes. From 

catalyzing reactions to protecting our body to supporting 

cell structure, proteins have a wide variety of functions 

based on each specific protein’s structure. Naturally-occurring 

proteins are perfectly evolved for their specific functions 

in each organism. Synthetically designed proteins, 

however, have the potential to solve the multitude of global 

problems facing the world today. For example, engineered 

bacteria can make enzymes that help decompose plastics 

and reduce landfill waste, or produce designer proteins that 

can harvest energy from sunlight for clean energy. 

Direct experimental methods for designing synthetic 

proteins can be used for creating new proteins with the 

desired activities, but they are expensive and labor intensive. 

Another strategy is to employ computer simulations, 

which have the potential to greatly streamline the process 

and reduce costs. However, despite a number of successes, 

computational protein design software still frequently 

makes inaccurate predictions of protein structure and interactions. 

To solve this problem, two Yale groups are combining 

their expertise in an interdisciplinary effort led by Corey 

O’Hern, an associate professor of Mechanical Engineering 

& Materials Science, and Lynne Regan, a professor of Molecular 

Biophysics & Biochemistry and Chemistry. 

In a recent Protein Engineering, Design, and Selection 

paper published in July 2016, the team of researchers described 

a new computational model that helps solve the 

“repacking” problem, allowing them to accurately predict 

how each amino acid side chain fits into the core of a protein. 

Amino acids are the fundamental building blocks of 

proteins, so understanding how they are positioned within 

proteins is crucial to understanding protein structure. “It 

may sound trivial, but it is not because you have to try all 

side chain conformations to determine which one will fit. 

Our simple model performed as well as the state of the art 

software in repacking amino acid side chains,” O’Hern said. 

Other approaches include all possible energetic contributions 

to protein structure, such as steric interactions, electrostatic 

effects, van der Waals attractions, and hydrogen 

bonding. In contrast, the O’Hern and Regan team used a 

somewhat unconventional approach to modeling proteins 

by only considering steric interactions—repulsive forces 

that prevent atomic overlaps. In their approach, the amino 

acids are modeled as 3D puzzle pieces that are arranged to 

fit into the protein core without overlaps. The model can 

accurately predict how each amino acid must be positioned 

to best fit into the core, just like the way Tetris pieces in 

the 1980s video game need to be in certain orientations to 

tightly fit together and not overlap. 

“Our intention was to determine how far we could go in 

protein structure prediction using the simplest model and 

only add in additional factors when the simplest model can 

no longer predict the experimentally observed data. That 

was our idea: a bottom-up approach rather than throwing 

everything in at the beginning,” Regan said. “Surprisingly, 

we found that our model performs extremely well simply 

by avoiding steric overlaps. We didn’t need to explicitly put 

in any attraction or hydrogen bonding [or other factors].” 

The team discovered that their simple model worked well 

on many more amino acids than they anticipated. Even 

so, they were able to identify its limits and simultaneously 

learn much about the dominant forces that determine protein 

structure. This point is well illustrated by comparing 

the two hydroxyl functional group-containing amino acids, 

threonine and serine, which are typically considered 

similar in biochemistry textbooks. Although the position 

of the threonine side chain can be predicted by steric interactions 

alone, inclusion of hydrogen bonding is required to 

correctly position the serine side chain. O’Hern and Regan 

propose that this is because the steric interactions of the 

additional methyl group on threonine are dominant. 

The team has already expanded their original studies to 

successfully repack multiple amino acid side chains simultaneously, 

and they are working on calculating the energetic 

cost of mutating amino acids in protein cores and at 

interfaces. The O’Hern and Regan team are poised to apply 

their novel approach and combined expertise to design 

proteins for sustainability, biomedical, and pharmaceutical 

applications. 

December 2016 


9

NEWS 

materials science 

SOLAR CELLS 

Organic solar cells reach new heights in efficiency 

►BY JOE KIM 

The old solar cell revolution has come to a halt. The types 

of solar cells that are now widespread were commercialized 

more than 50 years ago. Despite scientific improvements and 

increased attention to solar energy, the cost of conventional 

solar cells remains high due to the high cost of silicon, which 

converts solar energy into electric energy by producing 

electrons when light hits the silicon layer in the solar cell. 

Understanding the negative effects of fossil fuels and the 

necessity for cheaper renewable energy, scientists have worked 

on engineering new solar cell designs using different materials. 

Currently, in contrast to the inorganic solar cells that dominate 

the field, organic polymer solar cells have been getting much 

attention due to their mechanical flexibility, large area, light 

weight, and low costs in mass-scale production. Organic 

polymer solar cells differ in that carbon-based polymer is used, 

and not the conventional silicon. The main hurdle that many 

researchers face in developing organic polymer solar cells is 

their low efficiency. Although slow improvements have been 

made, the most common design, single-junction cells with 

only one electron-producing active layer, has only an eight 

to ten percent power conversion efficiency—far less than the 

commercially required efficiency of over 20 percent. 

Recently, researchers in professor Andre Taylor’s 

transformative materials and devices lab broke through the 

10 percent boundary by incorporating multiple cocrystalline 

squaraines into the solar cell’s active layer. These cocrystalline 

squaraines are organic fluorescent dyes that absorb light 

and produce electrons, which are then picked up by the 

interlayer to produce a current. Tenghooi Goh, a recent PhD 

graduate, explained that their new design, which contains a 

greater number of electron donors, allows the solar cell to 

absorb a wider range of wavelengths, or types of light. Typical 

polymer cells only absorb specific types of light and waste 

the light outside that range, resulting in decreased efficiency. 

However, Goh said that incorporating more materials is 

extremely complicated, as undesirable interactions between 

incompatible chemicals can occur. “Mixing things are not as 

simple and direct as it may suggest. In a lot of times, if you 

mix two incompatible things together…they actually drive 

down the efficiency instead of having a positive effect,” Goh 

said. Even with the setback, Goh stated this was a path to a 

fundamental breakthrough in organic polymer solar cell 

efficiency. Thus, the researchers focused on minimizing this 

potential destructive interaction. 

Previously, Goh and Taylor’s team successfully combined 

squaraine and high efficiency polymer component, thanks 

to certain properties of the system. Chromophores, or lightsensitive 

molecules, transfer energy between an acceptor 

and donor molecule through Förster resonance energy 

transfer (FRET). Goh referred to FRET as “a mechanism like 

photosynthesis, with electrons jumping over non-conducting 

gaps.” Therefore, FRET stabilized the final mixture by allowing 

energy to be transferred between materials, ultimately helping 

the team mix together potentially incompatible components 

so that the wide wavelength of light was preserved. The energy 

transfer between two squaraines, ASSQ and DPSQ, along with 

high performance electron donating compounds in active 

layers, helped stabilize the final mixture in the active layer. 

The team found that photovoltaic efficiency increased 

by over 25 percent on average between solar cells with and 

without ASSQ and DPSQ incorporated. In addition, multiple 

FRET pairs with rapid and efficient energy transfer were 

observed through spectroscopy techniques, which measures 

rapid changes in the absorbance of certain wavelengths of light. 

Such observations corresponded with the abovementioned 

explanation validating that FRET was indeed responsible for 

the stable combination of components. 

The solar cells have their shortcomings—Goh pointed 

out that the organic polymer solar cells are not free from 

environmental consequences such as harmful solvent waste. 

Even so, this research can provide greater benefits by lowering 

costs of production, leading to more widespread usage of 

solar cells and decreased fossil fuel usage. The efficiency of 

Goh’s team’s solar cell was recorded to be up to 10.7 percent, 

widely considered a milestone in efficiency of organic polymer 

solar cells. Furthermore, he added that this is before efficiency 

optimization by researching and modifying the layers 

surrounding the active cell. Goh is very hopeful about future 

research. “In the future, if we combine the pinnacle of different 

research together, we can probably reach greater efficiency.” 

PHOTOGRAPHY BY JOSHUA MATHEW 

►Research in Andre Taylor’s lab focuses on organic solar cells, which 

consist of thin films with unique light-absorbing and energy-transfer 

properties that allow them to harness solar energy more efficiently. 


medicine 

NEWS 

THE FLU SEASON CRAVINGS PARADOX 

The connection between metabolism and disease outcome 

►BY MARY CHUKWU 


PHOTOGRAPHY BY CHUNYANG DING 

►Yale researchers in Professor Ruslan Medzhitov’s lab found 

connections between metabolism and infection that may lead to 

new approaches to nutrition for the critically ill. 

As winter settles in, perhaps the only seasonal “foods” more iconic 

than hot chocolate and s’mores are cough drops and tea. Why do 

some people want to weather colds holding steaming bowls of comforting 

soup, while others suffer queasy stomachs and leave dinner 

plates untouched? The seemingly paradoxical appetite changes associated 

with sickness are a well-recognized and evolutionarily ancient 

trait, but up until now scientists could only speculate about 

their cause and purpose. 

Yale researchers led by Ruslan Medzhitov, professor of immunobiology 

at the Yale School of Medicine, have found that the answer 

to this puzzle lies with the causes of infection. The key insight of 

their research is that not all sicknesses are created the same. Fighting 

viral versus bacterial infections requires completely opposite 

nutritional needs. The findings of their research hold the potential 

to transform how healthcare approaches nutrition in illness. 

The researchers began by tracing out how anorexia, or loss of appetite, 

affects disease outcome in bacterial infections. Researchers 

infected mice with Listeria monocytogenes, a common cause of 

food poisoning. Mice that were fed during infection died; those 

who did not eat lived. 

Similarly, the researchers infected mice with influenza virus, the 

cause of the flu, and again varied caloric intake. Now the fortunes 

were reversed: fed mice survived viral infection while those that did 

not eat mostly died. These trends held true not only for infection 

but also when the experiments were repeated for bacterial and viral 

inflammation—whole body immune activation. 

The real story linking nutrition and disease, however, emerged in 

the search for the nutrient causing the outcomes. Between protein, 

fat, and glucose, only glucose was required to induce the complete 

effects of caloric intake. Moreover, blocking glucose utilization rescued 

bacteria-infected mice while killing virus-infected mice. 

Interestingly, glucose does not change the number of pathogens 

or the strength of the immune response. Instead, glucose 

shapes the role of metabolism in the body’s tolerance of the immune 

response. Metabolism refers to all the chemical reactions 

needed to sustain life; use of the immune system comes at a price. 

“Depending on the type of inflammation or infection, there 

are different metabolic processes that are necessary to survive the 

critical illness condition,” Medzhitov explained. Specifically, bacterial 

and viral infections generate different kinds of tissue damage 

depending on the presence of glucose. 

While glucose dominates metabolism in the fed state, during 

a fasting state the body begins breaking down fat stores to utilize 

molecules called ketone bodies for energy. Bacterial infections 

cause an immune response that releases reactive oxygen species 

(ROS), or “free radicals,” which kill pathogens as well as damage 

host cells. Glucose exacerbates this negative side effect while ketone 

bodies from starvation are protective. A parallel exists for 

viral infection. 

In response to the cellular damage caused by viral infection, 

the unfolded protein response (UPR) targets and eliminates cells 

producing abnormal proteins. This process is regulated by glucose—without 

glucose, this stress-induced response leads to excessive 

cell damage. 

“We discovered that by blocking glucose utilization in viral infections 

we prevented a normal response against viruses and instead 

caused a response that ended up being destructive for the 

host,” said Andrew Wang, first author and clinical fellow in medicine. 

Shockingly enough, the battleground where glucose decided 

life and death was not in the heart or the lungs, as may be expected 

for a pulmonary illness like the flu, but rather in the brain. 

PET scans and tissue studies revealed damage at critical sites in 

the brain following bacterial and viral infection. Absence of glucose 

increased neuronal damage in viral infections while for bacteria 

the opposite was true. The damage was once again linked to 

either overactivity of the UPR or overproduction of ROS. 

Medzhitov and his team hope that these new findings can 

improve nutrition for the acutely ill. Currently, all ICU patients 

are fed intravenous liquid food that is 30 to 60 percent carbohydrates, 

but Medzhitov’s study suggests that these formulations 

need to be adjusted based on the cause of illness. The Yale 

team is currently preparing clinical trials that test that premise. 

Future studies by the team will continue using mouse models 

to study different types of infections, including parasitic and 

fungal. Their work will contribute to new holistic models of 

healthcare treatment. 

“The general implication is that there is a certain wisdom 

to the body’s reactions and our preferences during illness, and 

many of these are protective,” Medzhitov said. In sickness at 

least, we can all benefit from listening to our bodies. 

December 2016 


11

A ROCKY ROAD 

TO THE PAST 

BY KEVIN BIJU 

ART BY EMMA HEALY 

TWO HUNDRED AND 

FIFTY TWO MILLION 

YEARS AGO, THE WORLD 

WAS ENGULFED IN A 

NIGHTMARISH SCENARIO 

AKIN TO WHAT WE 

FEAR TODAY.

environmental science 

FOCUS 

Surging carbon dioxide levels, 

combined with increased radiation 

from the Sun, dramatically increased 

global temperatures. Ocean surface 

temperatures reached upwards of 104 

degrees Fahrenheit. Consequently, mass 

extinctions occured, with marine and 

terrestrial life suffering huge losses in 

biodiversity. 

Until now, the scientific community 

has struggled to determine the relative 

importance of the two forces that drove 

the Permian-Triassic mass extinction 

event: volcanic activity and erosion. A 

study led by Ryan McKenzie, a postdoctoral 

associate at the Yale Department 

of Geology and Geophysics, has now 

proposed a solution. The study argues 

that on the time scale of the past several 

hundred million years, volcanoes have 

been the principal driver of climate 

change. These revolutionary findings are 

key to understanding long-term climate 

change, and thus, may prove informative 

in our present-day combat against global 

climate change. 

The greenhouse effect 

Carbon dioxide (CO 2 

) is a double-edged 

sword—both vital to life yet potentially 

harmful. On one hand, much of Earth’s 

plant life depends on CO 2 

to produce 

food for itself and consumers, like us. At 

the same time, increasing CO 2 

levels since 

the industrial revolution have led to rising 

global temperatures, which pose a risk 

to the global ecosystem. How does this 

happen? 

The Earth’s atmosphere normally 

reflects much of the Sun’s invisible 

infrared radiation back into space, 

thereby preventing surface temperatures 

from becoming too high. However, 

when sufficiently concentrated in the 

atmosphere, CO 2 

can form a blanket of 

sorts, which traps some of this radiation 

and prevents it from leaking back to space. 

Thus, CO 2 

is aptly termed a greenhouse 

gas. 

Various processes regulate the levels 

of CO 2 

in the atmosphere. Volcanic 

eruptions, which release gases from the 

Earth’s interior, contribute to atmospheric 

greenhouse gases and raise global 

temperature levels. Chemical weathering, 

on the other hand, has the opposite 

effect. When CO 2 

reacts with water vapor, 

carbonic acid is formed. This weak acid 

then eats away at rocks and other surfaces. 

Other forms of chemical weathering 

include burial of carbonate minerals, 

along with burial of organic carbon. Thus, 

chemical weathering is a CO 2 

sink and has 

the ultimate impact of decreasing global 

temperatures. 

The scientific community recognizes 

these two forces—volcanism and 

weathering—as the principal drivers of 

long-term climate change. Due to these 

two processes oscillating and changing 

pace over time, the content of CO 2 

in the 

atmosphere is in constant flux. Thus, the 

Earth’s temperature has risen and fallen 

multiple times within its history, creating 

various periods of global warming 

followed by global cooling in the form of 

ice ages. 

The unearthing begins 

The study began with McKenzie’s 

fascination with the links between climate 

change and biodiversity. “I became 

interested in the anomalies characteristic 

of the Cambrian period,” McKenzie said. 

“A lot of species extinction occurred, 

which many people attribute to the 

Cambrian having one of the highest 

atmospheric carbon dioxide levels of the 

past six hundred million years.” McKenzie 

set out to discover the root cause of this 

carbon dioxide flux. 

First, McKenzie and team needed to 

obtain a record of Earth’s volcanic history. 

The Earth is made up of multiple tectonic 

plates, which are large pieces of the Earth’s 

crust. When an oceanic plate collides 

with a continental plate, a subduction 

zone is formed. The oceanic plate sinks 

deeper into the earth, liberating water in 

the process. This water gradually seeps 

upward, melting the hot mantle rocks 

and forming magma in the process. 

This magma finally rises to the surface 

and forms a chain of active volcanoes. 

Unfortunately, however, it is often difficult 

to track the formation of these volcanic 

emissions through Earth’s history because 

erosion and destruction of volcanoes 

obscures the important data. In addition, 

the commonly used sea-level approach to 

track volcanic rates through time relies 

on too many vague assumptions. This is 

where zircons come in. 

Zircons, otherwise known as zirconium 

silicate, are grains of sedimentary rocks 

that crystallize from magma. Young zircon 

is especially prevalent in the subduction 

zones of continental volcanoes, such as the 

Andes and the Cascade volcanoes. Zircon 

grains are able to withstand high degrees 

of erosion, so they represent untampered 

records of volcanic activity. Fortunately, 

due to zircon’s uranium impurities, the 

age of zircon samples can be determined 

very precisely through radioactive 

isotope analysis. Thus, if one can trace an 

abundance of young zircon to a specific 

period, this period likely experienced 

massive continental volcanic activity. 

McKenzie and his team used this property 

of zircon to contribute to a precise record 

of continental volcanic activity throughout 

the geologic timeline. The team could now 

accurately map the relationships between 

carbon dioxide levels and volcanic activity. 

IMAGE COURTESY OF RYAN MCKENZIE 

►Dr. Ryan McKenzie stands with a fuming 

Mt. Bromo in Indonesia. McKenzie analyzed 

sedimentary rock to more closely link volcanic 

emissions to long-term climate change driven 

by carbon dioxide concentration. 


December 2016 


13

FOCUS 

environmental science 

Mapping the Earth 

IMAGE COURTESY OF RYAN MCKENZIE 

►Shown is a photo of Mt. Vesuvius in 

Italy. Data on sedimentary rocks in the 

area contributed to McKenzie’s analysis of 

volcanic activity. 

“In addition to the scientific literature, 

we did extensive work in India, Myanmar, 

and North China to fill in the existing gaps 

within zircon data sets,” McKenzie said. 

Compiling analyses of close to 120,000 

zircons, McKenzie’s team found a promising 

pattern. The Cambrian, Jurassic, and 

Cretaceous periods, which saw high levels 

of CO 2 

, had very high proportions of young 

zircons. In contrast, the Neoproterozoic, 

Carboniferous, early Permian, and 

Cenozoic periods, when CO 2 

levels were 

low, had low proportions of young zircons. 

“We were able to establish a crucial link 

between the oscillations of volcanic gas 

activity and the flux of greenhouse gas 

levels,” McKenzie said. 

The findings of this study fit well into the 

geographic framework of continental shifts. 

Multiple times throughout Earth’s history, 

continents have rifted and amalgamated. 

Rifting periods—times when continents 

separate from each other—create extensive 

subduction zones, which in turn fuel 

continental volcanic activity, increasing 

zircon and CO 2 

abundance. On the other 

hand, amalgamation periods—times when 

two continents combine—lead to a loss of 

subduction zones, reducing volcanic activity 

and therefore zircon and CO 2 

abundance. 

Thus, the results of McKenzie’s study 

could be verified by existing knowledge 

about continental shifts. Ultimately, the 

techniques used in this project provide 

strong proof of the versatility of zircon as 

an indicator of volcanic CO 2 

emissions. 

Thus, with this innovative zircon 

technique, McKenzie’s team has provided 

compelling evidence that volcanism has 

been an important driver of climate change 

over the past 700 million years. “Many of 

the specialists in this field were initially 

skeptical of this work, so we faced the 

challenge of revising popular opinion,” 

McKenzie said. While McKenzie and his 

group have primarily focused on volcanism 

as a key driver, they still recognize the 

importance of weathering in contributing 

to CO 2 

changes. However, they argue that 

weathering can be interpreted simply as a 

secondary effect of volcanoes. Volcanoes 

contribute the primary influx of CO 2 

into 

the atmosphere, so they exert the greatest 

first-order control over long-term climate 

change. 

However, volcanoes do not just act in one 

direction. Volcanoes result in both global 

warming and global cooling. According 

to other studies, a fuller consideration of 

the effect of volcanism on climate change 

must include the long-term effects of 

volcanic rocks. Indeed, volcanic activity 

can certainly lead to immediate increases 

in CO 2 

emissions, leading to higher 

temperatures. However, during periods of 

volcanic dormancy, the volcanoes can be 

weathered. This weathering removes great 

quantities of CO 2 

from the atmosphere, 

leading to a global cooling events. Thus, 

if considered on a long-term time scale, 

each volcano is both a carbon source and 

a carbon sink. Indeed, volcanism is a major 

force that regulates long-term climate 

change. 

Future digs 

Modern-day, human-driving global 

warming is a formidable challenge, 

especially given the jump in CO 2 

emissions 

in such a short period of time. But placing 

ourselves in geological time, we would see 

that global warming has occurred multiple 

times since the formation of the Earth’s 

atmosphere as CO 2 

levels oscillated with 

the rise and fall of continental volcanic 

activity. Global warming has defined the 

landscape of existing biodiversity and 

geography on Earth, notably during the 

Permian-Triassic extinction when 70 

percent of land species and 90 percent of 

marine species went extinct. Importantly, 

global warming of the past educates us on 

the critical interactions that occur between 

carbon sources and carbon sinks, which 

is a part of present-day human-driven 

climate change as well as the climate 

variation of the past. 

Moving forward, McKenzie’s research 

group refuses to be constrained to 

one specific goal. “Up until now, the 

constraints of our data have been limited,” 

McKenzie said. “We hope to look at more 

high-resolution data sets and put more 

real numbers to this data.” Indeed, to fully 

uncover the Earth’s rich history, we must 

be willing to constantly dig deeper. 

ABOUT THE AUTHOR 

KEVIN BIJU 

KEVIN BIJU is a sophomore Molecular Biophysics and Biochemistry major in 

Morse College. He is the Alumni Outreach Coordinator of the Yale Scientific 

Magazine and is interested in the cross-talk between evolution and genetics in 

biomedical research. 

THE AUTHOR WOULD LIKE TO THANK Dr. Ryan McKenzie for his thoughtful 

interview, as well as his research team’s dedication. 

FURTHER READING 

M. R. Burton, G. M. Sawyer, D. Granieri Deep carbon emissions from 

volcanoes. Rev. Mineral. Geochem. 75, 323–354 (2013). 


STICKING 

IT TO 

CANCER 

FIGHTING 

TUMORS WITH 

NANOPARTICLES 

BY JESSICA TRINH 

ART BY 

LAURIE WANG 


December 2016 


15

FOCUS 

biomedical engineering 

Eyes on the prize, you jump into a river, furiously swimming for the shoreline. 

Yet, the second you reach for it, the current pulls you away. This is the 

challenge cancer drugs face in the human body: rapid clearance from the 

treatment site. The protection and safe delivery of these drugs as they travel 

to their target region are important factors in the drug’s success. 

In order to combat this problem of rapid 

clearance, a group of Yale researchers 

has been studying therapeutic drug delivery 

through the use of sticky biodegradable 

nanoparticles. This technique targets tumors 

more efficiently by releasing drugs directly 

into the cancerous regions. The Yale study 

found that bioadhesive nanoparticles were 

capable of remaining in the tumor regions for 

long periods of time, demonstrating the potential 

for drug delivery through nanoparticles 

to fight cancer. 

Promising potential 

Surgery and chemotherapy are common 

treatments for aggressive tumors arising from 

the ovary and uterus. Unfortunately, many 

patients undergoing these therapies redevelop 

tumors or, in the case of chemotherapy, 

see their tumors become resistant to the 

treatment. For a little over the past decade, 

nanoparticles have emerged as a delivery 

system for agents such as drugs, targeting a 

larger portion of the drug to the tumor and 

causing less severe side effects. Nanoparticles 

can be engineered to enclose these drugs, 

protecting them on their way to the target site 

in the body. 

Nanoparticle size plays an important role in 

the drug’s ability to stay in the region of the 

tumor. Too large a particle results in the drug’s 

accumulation in the lower abdomen, while 

too small of a particle results in a greater 

chance of abdominal fluid clearing the drug 

out of the system. With successful control 

of nanoparticle size, however, nanoparticles 

have the potential to allow for safer and more 

effective cancer treatment. 

A sticky finding 

Mark Saltzman, a professor at the Yale 

School of Engineering and Applied Science, 

is working to harness the potential 

of nanoparticles. His team developed 

nanoparticles with an outer coating of a 

polymer known as hyperbranched polyglycerol 

(HPG). HPG nanoparticles are like 

branched trees, where each branch is terminated 

in water-loving groups that make the 

particles water-soluble. This specific HPG 

outer coating has proven to be more effective 

than even the most highly regarded 

particle coating, possessing higher stability, 

lower risk of absorption in the body by proteins, 

and longer circulation in blood. 

Experimenting with nanoparticles of 

different sizes, the team found nanoparticles 

measuring around 100 nanometers to 

be most effective in distributing throughout 

the body cavity and dispensing their 

encapsulated drug to the target site. The 

longer the time in the body, the longer the 

nanoparticles will release the therapeutic 

drugs into the tumors. 

Initially, Saltzman and his laboratory 

team worked with non-sticky nanoparticles 

that would circulate around the body 

for extended periods of time and eventually 

accumulate in the tumor. However, Yang 

Deng, a postdoctoral associate working in 

the laboratory, had an interesting finding. 

With organic chemistry techniques, he was 

able to make the nanoparticles that stick to 

protein-coated surfaces. This was done by 

using sodium periodate to transform the 

outer coating of the particles, generating 

aldehyde groups which are able to form 

bonds with other proteins. 

Once the team discovered these sticky 

particles, the race was on to find suitable 

applications. The team was able to invent 

a new kind of sunblock that lasted longer 

on the skin, taking advantage of how the 

nanoparticles could stick to the skin’s top 

layer. However, the researchers also realized 

they could apply these sticky nanoparticles 

to areas such as cancer treatment. This is 

where Alessandro Santin came in. 

Alessandro Santin, a professor at the Yale 

School of Medicine, treats patients with gynecological 

tumors with origins in the uterus 

and ovaries. In some cases, the tumor 

spreads out of the reproductive tract and 

into the abdomen, where it would grow in 

PHOTOGRAPHY BY GEORGE ISKANDER 

►A member of the Saltzman lab prepares 

reagents for her experiment. The Saltzman 

lab has pioneered the use of nanoparticles 

for drug delivery. 

little clusters of cells that stick to the membrane 

surfaces of the abdomen. 

Saltzman believed his sticky nanoparticles 

were relevant to Santin’s work for 

a variety of reasons. “If they’re sticky, 

we thought they would stick to the same 

membranes that the cancer cells stick to 

and they should get all over the abdomen, 

and eventually stick to the same surfaces 

tumor cells stick to,” Saltzman said. 

Saltzman and his team hypothesized that 

the sticky nanoparticles they had created 

could be applied to deliver drugs to tumors. 


iomedical engineering 

FOCUS 

Targeting tumors with drugs 

Saltzman, Santin, and their team sought 

to apply the their invention to cancer therapy. 

First, they tested how adhesive the sticky 

nanoparticles were compared to nonadhesive 

nanoparticles. To do this, they tested both 

particles in human umbilical cords, measuring 

how long they remained on the luminal 

surface. As a marker to quantify the level of 

adhesiveness, both particles were loaded with 

a dye, which emitted a fluorescent signal corresponding 

to the amount of particles in the 

region. The results showed that the bioadhesive 

nanoparticles had a longer signal time 

than that of their non-sticky counterparts. 

Now, the researchers could proceed with 

loading a drug into these nanoparticles. 

Epothilone B (EB), a drug that inhibits 

microtubule function, can prevent cancer 

cell division . The researchers chose to load 

EB into these sticky nanoparticles because 

of its efficacy against both ovarian and uterine 

cancers. However, the drug comes with 

its dangers. “The problem with this drug is 

that it’s so potent at killing cancer cells that 

it’s toxic,” Saltzman said. Therefore, a way 

to introduce the drug to the cancerous region 

gradually and more directly is crucial. 

Saltzman hypothesized that by injecting 

these EB-loaded bioadhesive nanoparticles 

into the space between the membranes that 

line the abdominal cavity, they could get 

the nanoparticles to form bonds with the 

proteins on the tissue surfaces. This would 

increase the length of time over which drug 

would be delivered to the tissue. 

Traditionally, nanoparticles injected in 

this manner would be quickly cleared from 

the abdominal region. With the bioadhesive 

nanoparticles, however, the protein bonds 

formed with the cells layering this region 

held the nanoparticles in place. “We showed 

that if you take the particles and you expose 

them to a protein-coated surface, they stick 

very well,” Saltzman said. If successful, this 

would increase the bioavailabilty of the drug. 

To test if this indeed happened, the researchers 

created a mouse model with human 

tumors in the abdominal region to simulate 

the environment in a human cancer 

patient. They loaded EB into the nanoparticle 

vectors and injected them into the mice. 

The results were promising: at the end of four 

months, the mice subjected to this treatment 

had a 60 percent survival rate, whereas only 

10 percent of mice survived in the control 

groups. “We showed that by putting it in our 

bioadhesive nanoparticles, we can keep it in 

the abdomen for a long time with very little 

toxicity, particularly compared to the drug 

itself,” Saltzman said. 

Sticking with it 

The results of the Yale study offer the potential 

for more efficient methods for delivering 

drugs to target tumor cells. In the 

future, the researchers hope to increase the 

efficiency of drug delivery. For example, Santin 

is working on designing homing peptides 

that would target tumors specifically. “Doing 

so may increase the antitumor activity of the 

nanoparticle treatment,” Santin said. 

Yet, more research needs to be done on the 

deliver system used in the study. Saltzman 

states that the researchers did not see a specific 

immune response when they observed 

general markers of immune activation, but 

that there are still more areas of concern to 

be addressed before the drug delivery system 

is ready to be used for cancer patient treatment. 

According to Santin, the researchers 

are working on an investigator-initiated trial 

using the drug. “This clinical trial will help to 

understand the potential of this novel agent 

in the treatment of chemotherapy-resistant 

ovarian cancer,” Santin said. 

The results of the team’s work indicate the 

potential for bioadhesive nanoparticles as 

drug delivery agents to cancerous tumors. 

With more research on safer cancer treatment 

methods, nanoparticles may become a 

powerful weapon in our arsenal against devastating 

cancers. 


JESSICA TRINH 

JESSICA TRINH is a freshman and prospective biomedical engineering major 

in Branford. She enjoys volunteering for Synapse, Yale Scientific’s volunteer 

outreach program, being the Director of Operations for Resonance, Yale 

Scientific’s high school outreach program as well as the Communications 

Chair for Yale’s chapter of STEAM. 

THE AUTHOR WOULD LIKE TO THANK Dr. Mark Saltzman and Dr. 

Alessandro Santin for their time and enthusiasm. 


December 2016 


17

CANINES ARE OVER 

OVERIMITATION 

BY ANNA WUJCIAK | ART BY OLIVIA THOMAS 

When, as a child, we were learning 

to tie our shoes, we painstakingly 

followed the directions of our 

parents or a nursery rhyme. When we were 

picking up dining etiquette, we carefully 

observed the way others use the utensils. 

When we navigate our first day at school 

or at the workplace, we are quick to do as 

our colleagues do. Imitation is the foundation 

of our socialization. But sometimes, 

our tendency to replicate others extends 

beyond necessary or efficient actions, a 

phenomena scientists call overimitation. 

Overimitation is a human-specific form 

of social learning in which we faithfully 

copy irrelevant actions. It is largely responsible 

for the ability of our species to 

have so many rich cultural traditions and 

advanced technology because we are able 

to handle more information by accepting 

the way that other people behave. 

The purpose of a recent Yale study was 

to explore whether dogs and dingoes also 

display overimitation. There are many 

reasons to expect that dogs might follow 

human cues. For one, they follow human 

gaze and directions, and studies have repeatedly 

shown that dogs are prone to look 

for a human lead. Surprisingly, the results 

revealed that canines do not display this 

behavior, suggesting that humans are the 

only species to demonstrate this behavior. 

The merits of overimitation 

One of the most obvious drawbacks of 

overimitation is that it can cause a person 

to be misled. However, the benefits are 

much greater. Consider activities as mundane 

as washing your hands or brushing 

your teeth. It is important for health reasons 

that young children replicate these 

behaviors at a young age, regardless of 

whether they understand the reasoning 

behind the action. 

Thinking even further back, consider the 

Stone Age. Learning how to start a fire may 

have been more likely to persist because 

individuals had a tendency to overimitate 

the demonstrator. A stick must be spun 

quickly for a long time to create a spark. If 

the learner did not have the inclination to 

continue spinning the stick, despite its apparent 

uselessness, then they may not have 

been able to start a fire. Without the ability 

to start fire, our species would not have 

moved on to designing simple machines 

and advancing technology. 

Overimitation may also be particularly 

responsible for the depth and longevity 

of human culture. Other species do not 

have traditions. Humans maintain rituals 

by passing their knowledge on through 

generations, although it might not be 

necessary or relevant. Consider religious 

practices or decorative dressing that have 

survived for centuries; without overimitation, 

these practices could have been discarded 

as ornamental and extraneous. 

A drawback of overimitation is that it 

can sometimes constrain our exploration. 

Overimitation may dampen human trial 


cognitive science 

FOCUS 


ANNA WUJCIAK 

ANNA WUJCIAK is a senior Biomedical Engineering Major in Saybrook 

College. She works in Jay Humphrey's lab studying cardiovascular 

biomechanics and is a member of the Women's Club Water Polo Team. 

THE AUTHOR WOULD LIKE TO THANK Laurie Santos, Angie Johnston, 

and Paul Holden for their time and passion for their research. 

IMAGE COURTESY OF THE DOG BREED INFO CENTER 

►Dingoes look very similar to dogs. Yet, 

there are stark differences, both physical and 

psychological, between the two species of 

canines. 


Smith, B. & Litchfield, C. (2010). Dingoes (Canis dingo) can use human social 

cues to locate hidden food. Animal Cognition, 13, 367-376. 

and error behavior, while other species are 

more inclined to engage in this behavior 

because they do not automatically accept 

the information others have given them. 

Canine independence 

At the Canine Cognition Center at Yale, 

professor Laurie Santos, PhD candidate 

Angie Johnston, and research assistant 

Paul Holden explored whether dogs displayed 

overimitation. Dingoes were studied 

similarly at the Dingo Discovery Center 

(DDC) in Australia. Dogs were then 

compared to dingoes, a closely related but 

non-domesticated species, in an effort to 

explore the role of domestication. 

In four different trials, animals were 

tasked with opening a box to retrieve the 

treat inside. These boxes, which Holden 

designed at the Yale Center for Engineering 

Innovation and Design, were equipped 

with a lever on the side and a treat underneath 

a flip lid. Although the flip lid was 

necessary for getting the treat, the lever 

was completely ineffective. At the beginning 

of each test, a human completed both 

the relevant and irrelevant steps in the 

process of opening the box three times 

as a display for the animal. The box was 

considered solved if the animal was able to 

retrieve the treat. 

Results showed the dogs and dingoes 

filtered out the irrelevant lever action, 

even though it was demonstrated to them. 

With each of the four tries the test subjects 

had with the box, the rate of using the irrelevant 

lever decreased and the rate of 

solving the box increased. This indicated 

that both species of canines were learning 

which actions were relevant and which actions 

were not based on their own learning 

experiences. 

Although neither canine species displayed 

overimitation, there were differences 

in the two species. “Dingoes were 

using the lever less than dogs,” Holden 

said. “At first glance, dogs and dingoes 

look quite similar, but they’re actually very 

different.” Dingoes are clever problem 

solvers because they are more attentive 

and independent, Johnston added. Dogs 

have become domesticated over time due 

to their companionship with humans, and 

therefore they tend to look toward their 

human more often when a problem arises. 

As dogs have come to rely on humans 

more, they may have also become less 

adept at independent problem solving, 

which might explain why they used the lever 

more frequently than dingoes. 

A human behavior 

The brain mechanism behind overimitation 

is not yet well understood. Although 

it is outside the scope of Santos’s psychology 

lab, other researchers are exploring the 

complex brain processes that control decision-making 

and overimitation. 

Unfortunately, outside of dogs, dingoes, 

and chimpanzees, not many species have 

been tested for overimitation behavior. 

Dogs were selected as a species to study 

specifically at Yale because they are highly 

social. Chimpanzees have previously been 

studied because of their high intelligence 

and social tendencies. Scientists assume 

that since the closest relative to the human, 

the chimpanzee, does not display 

this behavior, it is human specific. The absence 

of overimitation in chimpanzee behavior 

also indicates that humans evolved 

this trait sometime within the last seven 

million years since our species diverged. 

Corvid species, which include birds and 

crows, may be valuable to explore next, 

as they are also very intelligent creatures. 

“Most animals exhibit innate behaviors 

that they’ve developed over many years 

of evolution,” Johnston said. For example, 

think of squirrels who bury nuts every 

winter. 

If not from overimitation, how do other 

species pass on information? Johnston 

explained that animals learn through observation, 

as opposed to the intentional 

instruction method of passing information 

like humans. Some information, such 

as locomotion, is instinctual. “It’s not that 

other animals can’t imitate, it’s just that 

they only do it when they need to, whereas 

humans tend to do it much more often 

than necessary. Animals are better at 

prioritizing the information they really 

need,” Johnston said. While humans have 

complex technology and intricate cultural 

practices, other species have more basic 

tasks that they can typically address on 

their own. Our species is the only one 

with a culture that forces us to rely on others. 

There are two general hypotheses about 

the driver of human overimitation. The 

first is that humans can’t help but overimitate. 

The second is that humans assume 

that the actions they observe are the culturally 

appropriate way to behave. “My 

thoughts are that it’s really a combination 

of both of these hypotheses that cause humans 

to overimitate,” Santos said. 

Overimitation, for better or worse, 

seems to be a distinctly human behavior. 

It assists our species to pass on complex 

cultural information and maintain a high 

degree of advanced technology. It certainly 

appears that overimitation is one of the 

reasons that humans differ so greatly from 

all other species. 


December 2016 


19

FOCUS 

evolutionary biology 

PERPLEXING 

FOSSILS & 

PECULIAR 

FORMS 

MAPPING THE TULLY 

MONSTER ONTO THE 

TREE OF LIFE 

by Andrea Ouyang | art by Emma Green 

One of the miracles of science is its 

ability to extend human memory. As 

our computational and technological 

capabilities expand, the searchlight of history 

broadens our vision into our past and uncovers 

new revelations and mysteries alike. Few fields, 

then, provide more fascinating applications of 

science than the tireless efforts to trace the evolutionary 

relationships of creatures, dead and 

alive, who populate the tree of life. 

Enter Tullimonstrum gregarium. 

In the 1950s, Francis Tully discovered a bizarre 

fossil in Mazon Creek, Illinois—a site 

known for the quality and diversity of creatures 

preserved in its deposits, formed 300 million 

years ago in the Carboniferous period. For half 

a century, no one was quite sure what to make 

of the fossil, dubbed the Tully Monster and 

declared the state fossil of Illinois in 1989. This 

oddly shaped sea creature did not fall under 

any neat category, with its pair of cuttlefish-like 

fins, long proboscis, and small sharp teeth. Indeed, 

paleontologists variously suggested the 

organism belonged to animal groups ranging 

from wormlike animals to mollusk-like creatures 

and even to fish. 

A Yale-led research team, led by then graduate 

student Victoria McCoy, has at last identified 

the Tully Monster. Combining morphological 

analysis and close examination of 

features resulting from the fossilization process, 

the researchers found that the Tully Monster 

was most likely a vertebrate with lamprey-like 

features. The study, published in April, has put 

to rest the mystery of the Tully Monster while 

also opening new avenues to further explore 

the life of this extraordinary animal. 

The exemplary enigma 

For a long time, the phylogenetic origins of 

the Tully Monster were unknown. 

“It’s a classic example of what we generically 

call a ‘problematic fossil,’ which is a way of 

saying we don’t really know, or didn’t know, 

what it was or where it sat in the grand scheme 

of things,” said co-author Derek Briggs, a professor 

of Geology and Geophysics at Yale and 

curator at the Yale Peabody Museum. "There 

were a number of these problematic fossils in 

older rocks, particularly during the Cambrian 

explosion 530 million years ago," Briggs said. 

This explosion of life saw the evolution of 

animals that would look alien to us today, but 

which were actually early offshoots of lineages 

leading to modern groups. Subsequently, most 

of these peculiar-looking fossils disappeared, 

replaced by groups more recognizable to paleontologists 

today. 

“What we see in the fossil record later on are 

generally things that we can identify, or at least 

relate to living groups,” Briggs said. “The Tully 

Monster was one of those exceptions.” Present 

in Carboniferous rocks dating from about 300 

million years ago, the Tully Monster was considered 

one of the problematica, or fossils that 

are difficult to classify. Besides its aquatic environment, 

no one really knew anything about it. 

Previous solutions to this “problem of the 

problematica” included simply classifying the 

problematica as phyla that went extinct—in 

other words, they were considered a long, divergent 

branch of the evolutionary tree of life 

that had been cut short, rather than a branch 

more closely nested in ancestral animal groups. 

Though modern computational approaches to 



FOCUS 

classification have resolved lingering questions 

about many previously problematic fossils, the 

Tully Monster had largely resisted phylogenic 

placement. 

The mission begins 

In 2015, McCoy was leading the Briggs lab 

group’s annual project, on which all the researchers 

in the group were collaborating. 

“The Field Museum independently thought 

that they would want someone to look at the 

Tully Monster, so I independently met with 

the Field Museum and curators and collection 

managers at the Geological Society of America 

meeting,” McCoy said. “We both kind of 

simultaneously said we’d like to work on the 

Tully Monster.” 

The Field Museum, in Illinois, is the closest 

major museum to Mazon Creek, where the 

majority of Tully Monster fossils have been 

unearthed. Its close relationship with local collectors 

has helped it acquire a vast collection 

of Tully Monster fossils—at over 2,000 specimens, 

the largest in the world—which made it 

the ideal location to work on the project, according 

to Briggs. 

It’s elemental, not elementary 

Part of what helped the Yale team succeed 

where others had failed was meticulous attention 

to detail. The fossilization process, though 

permitting long-term preservation, can make 

morphological features difficult to decipher as 

organisms decay and fossilize. 

In total, the researchers examined around 

1,200 Tullimonstrum specimens, organ by organ, 

for general morphological features. As an 

example, at the end of the Tully Monster’s proboscis, 

the team counted and measured teeth 

structures and studied how they were situated 

in the Tully Monster’s claw structure. They also 

looked at features such as whether the eye bar 

sat at the top of the head or went through the 

center of the body. 

The second component of the research involved 

studying features of preservation where 

the Tully Monster was discovered. The fossils 

were preserved as a discolored film on surrounding 

rock where the organism had been 

buried, and what appear to be morphological 

features sometimes are merely discoloration 

from the fossilization process. 

This combined analysis of morphological 

and preservational features in the Tully Monster 

helped McCoy and the team conclude that 

the Tully Monster had a notochord, a cartilaginous 

skeletal rod and evolutionary precursor 

to the spine that classified the fossil as vertebrate. 

The researchers had noticed a long line 

running down the middle of specimens, previously 

identified as the gut of the organism. 

While it was entirely possible that the line was 

the fossil imprint of either a gut or a notochord, 

examining preservation in conjunction with 

morphology allowed the researchers to determine 

which feature it was. 

To further test the vertebrate hypothesis, 

the researchers took specimen samples to Argonne 

National Laboratory for synchrotron 

analysis, a technique that allowed the team to 

determine which elements in a sample were 

enriched, what differences existed in the elemental 

composition of different tissues, and 

when they were preserved in the fossil. The 

synchrotron data indicated that Tully Monster 

eyes were often preserved in pyrite mineral, a 

preservational feature shared only by the fish 

—the other chordates—at the fossil site. This 

was particularly strong evidence that the Tully 

Monster was preserved similarly to fish, rather 

than other proposed animal groups, such as 

worms or mollusks. 

The researchers also found that Tully Monster 

teeth had a distinct composition from that 

of the rest of the bifurcated, claw-like structure 

at the end of its proboscis. This discovery also 

pointed to chordate affinity, since arthropods, 

another previously proposed position for the 

Tully Monster, have teeth-like spikes made of 

the same material as their claw. Fish teeth, on 

the other hand, are biomineralized—minerals 

were produced in those tissues to harden them, 

making teeth tissue distinct from the rest of the 

fish’s mouth. 

The teeth were pyritized, or replaced with 

iron sulfide, suggesting they were composed 

of sulfur-rich material, but not biomineralized, 

in contrast to most cartilaginous fishes, 

like sharks, whose fossils typically contain 

calcium or phosphate compounds. The sulfur-rich 

soft tissue was likely made of keratin, 

a sulfur-containing protein that is the main 

component of fingernails. Interestingly, keratin 

is also a component of hagfish and lamprey 

teeth, which do not biomineralize, so the 

researchers could conclude not only that the 

Tully Monster was a chordate, but also that 

it preserved similarly to soft-bodied fish like 

lampreys and hagfish. 

A fossil’s future 

Future studies of the Tully Monster include 

understanding its ecology and interactions 

with its environment and other organisms of 

the Carboniferous. It is unknown whether it 

was a parasite (like modern lampreys) or a 

scavenger, an ambush predator or one that 

could sustain periods of continuous swimming. 

Its many morphological oddities make 

it particularly compelling to study, according 

to McCoy. 

Luckily for researchers, the Field Museum 

recently acquired more Tullimonstrum fossils, 

a collector’s gift that could provide researchers 

the opportunity to explore and refine 

their findings against the new specimens. An 

important step, according to Briggs, is to examine 

the new collection and see whether it 

supports the team’s conclusions. While the 

Tully Monster may be long dead and gone, 

the story of its existence is sure to fascinate 

generations to come. 


ANDREA OUYANG 

ANDREA OUYANG is a sophomore and prospective MCDB major in 

Davenport College. 

THE AUTHOR WOULD LIKE TO THANK Dr. Victoria McCoy and Professor 

Derek Briggs for their time and enthusiasm in speaking about their work. 


Clements, T. “The Eyes of Tullimonstrum reveal a vertebrate affinity.” Nature 

532, 500-503, 2016. 

Richardson, E.S. “Wormlike Fossil From the Pennsylvanian of Illinois.” 

Science 151 (3706), 75-76, 1966. 


December 2016 


21

FOCUS 

physics 

E X P A N D I N G 

the Quantum Computing Toolbox 

By Noah Kravitz 

Art by Yanna Lee 


physics 

FOCUS 

In 2011, Canadian tech company 

D-Wave stunned the world by announcing 

that it would market a 

functioning quantum computer. Soon, 

companies ranging from Google to NASA 

bought versions of the device, and scientists 

began scrambling to evaluate what 

potentially was the biggest technological 

breakthrough of the century. One 

third-party test, in which the new quantum 

computer solved a complex math 

problem 3,600 times faster than a cutting-edge 

IBM supercomputer, seemed 

to substantiate D-Wave’s claims of quantum 

computation. Other tests found 

no evidence of quantum activity at all. 

Quantum computing, an idea which has 

captivated physicists and computer scientists 

alike since its conception in the 1980s, 

has proven difficult to realize in practice. 

Because quantum computers rely on the 

uncertainty built into the laws of quantum 

physics, they are extremely sensitive to 

their environments. A small imperfection 

in even a single component of the design 

can be devastating. One technical challenge 

is that heat energy can disrupt the 

fragile quantum states, so quantum technology 

is usually cooled almost to absolute 

zero (-273 degrees Celsius). D-Wave’s 

quantum computer is small enough to 

hold in the palm of your hand but has to 

be housed in a 10-foot-tall refrigerator. 

Yale researchers, led by Professor of 

Electrical Engineering and Physics Hong 

Tang, have developed a new version of a 

device called a piezo-optomechanical resonator 

that could allow quantum computers 

to operate at higher temperatures. The 

paper, which is co-authored by graduate 

students Xu Han and Chang-Ling Zou, describes 

an improved method of connecting 

information in physical and electrical 

domains. This advance could be used as 

the basis for reliable memory storage for 

quantum computers—an important step 

towards stronger quantum computing. 

From Schrodinger’s cat to national 

security 

Quantum computing fundamentally 

differs from classical computing in that 

it relies on the non-intuitive quantum 

properties of light and matter. In familiar 

classical computation, information is 

stored as bits which can take on the values 

0 and 1—they are simple on/off electrical 

switches, and it is easy to check their 

positions. The computer then performs 

tasks using sequences of logical operations 

on the bits. For example, it might 

say that if bit A is 0, then bit B should 

be set to 0, but if bit A is 1, then bit B 

should be set to 1; or that bit C should be 

set to 1 only if bits A and B are different. 

In quantum computing, by contrast, the 

situation is not so straightforward. First of 

all, information is stored in qubits (short 

for “quantum bits”) which have more than 

two possible values: 0, 1, and a combination 

of 0 and 1. These qubits are particles 

with distinct measurable quantum states 

corresponding to “0” and “1,” but one of 

the principles of quantum physics is that 

sometimes we can predict the result of 

a measurement only in terms of probabilities. 

So in quantum mechanics, even 

though sometimes we might know that 

we will always measure the particle as “0,” 

there can also exist a scenario in which 

there is a 50 percent chance of finding the 

particle in the “0” state and a 50 percent 

chance of finding it in the “1” state. The 

surprising part is that, mathematically 

speaking, the latter particle is actually in 

both states equally until we measure it as 

being in one or the other, and it is meaningful 

to think of such a qubit as having 

value ½ representing a “mixed” state even 

though ½ is not a possible measurement. 

Another useful property of quantum 

mechanics called entanglement links the 

measurements of different particles. For 

example, if particles A and B are entangled, 

then we might know that whenever 

we measure both particles, we will get one 

“0” and one “1.” In this case, measuring 

one qubit immediately determines the 

value of the other, and it is possible to use 

this property to “teleport” information! 

The unique logical underpinnings of 

quantum computation allow quantum 

computer to approach old problems in 

new ways. Since qubits are more complex 

than regular bits, quantum algorithms are 

often more streamlined than their classical 

counterparts, especially when searching 

for optimal solutions to problems. For 

example, if we want to find a car that is 

hidden behind one door out of a million, a 

classical computer would have to check the 

doors one by one, and, in the worst-case 

scenario, it would have to make a million 

queries. A quantum computer, by contrast, 

can use a probabilistic algorithm to find 

the car in at most only a thousand queries. 

Quantum computation has potential applications 

in many problems that would 

take classical computers longer than the 

age of the Earth. In the best-known example 

of this principle of “quantum speedup,” 

computer scientists have created a quantum 

algorithm that can factor large numbers 

(essentially a needle-in-a-haystack 

problem like the car example above) exponentially 

faster than is possible for any 

classical algorithm. Although this problem 

may not seem very exciting, it in fact underlies 

many more complex processes such 

as cryptography. Similar principles apply 

to choosing cost-effective combinations of 

building materials and even to identifying 

keywords for news articles. Unsurprisingly, 

quantum computation is often the best 

way to model complex natural systems. 

We have made significant progress over 

the past few decades towards meeting the 

challenges of quantum computing. As early 

as the mid-1990s, we have manipulated 

qubits and written codes to correct spontaneous 

errors in quantum computers. In 

the 2000s, we demonstrated long-distance 

entanglement. In 2013, Hong Tang and his 

team contributed to the corpus of knowledge 

when they determined a method 

for measuring quantum systems without 

permanently altering them. Now, in 2016, 

the Tang Lab at Yale has once again expanded 

the quantum computing toolbox, 

this time in the stubbornly challenging 

field of information storage and transfer. 

A new approach to quantum memory 

You probably carry around in your 

pocket a crucial piece of the new Yale 

device: Smartphones contain the materials 

that Tang and his team used to bridge 

the mechanical-electrical gap. Piezoelectrics 

are materials, usually crystals, that 

accumulate charge when compressed, 

twisted or bent. For instance, when 

a piezoelectric sheet is creased, a net 

negative charge forms at the fold, and 

net positive charges form at the ends. 

Conversely, when an external magnetic 

field causes charges in a piezoelectric to 


December 2016 


23

FOCUS 

physics 

IMAGE COURTESY OF HONG TANG 

►Professor Hong Tang (right), along with graduate students Chang-Ling Zou (left) and Xu Han 

(not pictured), developed a piezo-optomechanical resonator that has applications to quantum 

memory storage. 

move, the object responds by changing 

shape physically. In this way, vibrations 

in physical objects and electrical fields 

can easily be connected, or, as physicists 

say, coupled. Piezoelectrics in smartphones 

often power tiny speakers— they 

convert electrical signals into sound 

waves, which arise from physical pulses. 

The Yale piezo-optomechanical device 

consists of a pair of tiny resonators: 

a silicon wafer and a wire loop situated 

above it. “It is useful to think of a resonator 

like a tuning fork because it responds 

most powerfully to a particular resonant 

frequency,” said Han, an electrical engineering 

Ph.D candidate who worked on 

the project. The two ends of the wire 

loop do not quite connect, so electrical 

charges tend to bounce back and forth 

around the circle, which functions as an 

electrical resonator in the microwave region 

of the electromagnetic spectrum. 

The wafer, which is about as thick as five 

sheets of paper, functions as an acoustic, 

or mechanical, resonator. This resonator 

is coated with a thin layer of aluminum 

nitride, a piezoelectric material, 

which facilitates the exchange of oscillations—and 

energy— between mechanical 

and electrical components. “If you 

want to transfer information between 

two systems, it is necessary to have an 

efficient coupling mechanism,” Han said. 

The idea of coupling between mechanical 

and microwave electrical domains 

is not new; the Yale team’s innovation 

is achieving stronger coupling on a 

smaller scale. The key is using resonators 

with a higher frequency: Whereas 

other designs have used frequencies on 

the order of a few million oscillations 

per second, the Yale design runs at ten 

billion oscillations per second. As a result, 

the device is solidly in the so-called 

strong-coupling regime —meaning that 

the rate of information transfer is greater 

than the natural energy dissipation 

rates of the individual systems—and 

transmitted signals are clearer and longer-lasting. 

Yet high frequency comes at 

the cost of increased construction difficulties. 

“Since the device is small, it 

is more susceptible to perturbations in 

the environment,” Tang said. As a result, 

the design carefully balances considerations 

of compactness and robustness. 

The researchers believe that applications 

of their breakthrough lie mostly in the far 

future. “This is fundamental research, so 

it’s not immediately pertinent to daily life,” 

Han said. Instead, the piezo-optomechanical 

resonator’s real value is as a component 

of more complex systems. Because of the 

strong coupling achieved, it is well suited 

for quantum uses where “noise” from ambient 

heat (analogous to TV static) would 

otherwise be disruptive. “For high-frequency 

devices, the temperature requirement is 

not as low,” Han said. Chang-Ling Zou, a 

postdoctoral student in Tang’s lab, hopes to 

develop this strength into a basis for quantum 

memory storage, which is currently 

unfeasible at most temperatures. Small 

vibrating crystals would serve as physical 

memory, and the resonators would convert 

between these crystals and the computational 

part of the computer, which would 

likely operate in the microwave domain. 

The Yale team is also looking to incorporate 

visible light into their design. “The 

next step is integrating an optical resonator 

and using the acoustic resonator 

as an intermediary between microwave 

and optics,” Han said. Accomplishing 

this feat could improve computer signal 

processing, radio receiving efficiency, 

and information transmission across 

long distances via optical fiber cables. 

Given its versatility, the piezo-optomechanical 

resonator may find its way into 

all kinds of applications. From analyzing 

the stock market to sending trans-Atlantic 

messages, you can expect to hear more about 

this small device in big-time situations. 


NOAH KRAVITZ 

NOAH KRAVITZ is a freshman in Calhoun College. He is interested in 

studying math, music, physics and philosophy. 

THE AUTHOR WOULD LIKE TO THANK Xu Han, Chang-Ling Zou, and 

Professor Hong Tang for explaining their research. 


Li, Mo, W.H.P. Pernice, and H.X. Tang. “Ultrahigh-Frequency Nano- 

Optomechanical Resonators in Slot Waveguide Ring Cavities.” Applied 

Physics Letters 07 (2010). 



FEATURE 

A WORLD OF WONDER 

Opening the David Friend Hall at the Peabody Museum 

►BY CHUNYANG DING 

Nearly every observed galaxy has a giant black hole at 

its center. Step into the Peabody’s new David Friend Hall 

and it might take a minute for your eyes to adjust to the 

darkness—and then another hour for your mind to adjust 

to the dazzling marvels that surround you. From the 

2000-pound, single-quartz crystal from Namibia to the 

30-million-year-old sandstone concretion with smooth 

undulating curves, each object in the hall aims to wows 

visitors. Curators carefully chose every detail—from the 

lighting to the case design—to showcase the world-class 

treasures here in New Haven, Connecticut. 

Dramatic lighting highlights specimens with dazzling 

clarity and draws attention to the kaleidoscope of colors 

filling the hall. This focus on showmanship was well 

developed; David Friend (YC ’69), who donated three 

million dollars for the exhibit, hoped to fill people with 

a sense of wonder. “The function of a museum is not so 

much to teach but to inspire a desire to learn,” Friend 

said shortly before he cut the ribbon to officially open 

the exhibit. 

It is fitting for Yale to host this transformative mineral 

exhibit, since modern mineralogy originated here. Just 

as Carl Linneaus brought order to the natural world 

by classifying plants and animals, Yale professor James 

Dwight Dana brought order to the world of rocks and 

minerals with a classification scheme that is still used 

today. Geology has always been strong at Yale; Benjamin 

Silliman, Yale’s first science professor, started the 

American Journal of Science in 1818. Not only is the AJS 

IMAGE COURTESY OF MICHAEL MARSLAND 

►Prominent members of the Yale and New Haven communities 

attended the ribbon cutting ceremony with David Friend (YC 

’69). The opening speeches set the tone for an exhibit that 

would wow visitors. 

the oldest scientific journal in the United States, it is one 

of the most influential journals in the fields of geology 

and mineralogy. 

The Peabody Museum continues to challenge the 

expectations for natural history museums with the David 

Friend Hall. Rather than bombard visitors with text, the 

exhibit isolates the singular beauty of sparkling minerals. 

Educational materials for the displays are captured by a 

smartphone application, where visitors can access and 

browse background information. In addition, the gallery 

will feature rotating exhibits: many gems are on loan from 

private collectors, so new treasures can be featured in the 

future. Although art galleries often feature loaned art, 

the David Friend Hall is one of the first natural history 

exhibits to do the same. 

And the treasures are dazzling, indeed. Beside the 

2000-pound quartz stands a giant geode from Uruguay, 

completely encrusted by deep purple amethyst shards. 

Nearby, a white-board-sized fossil of a fan-like frond 

flanked by ancient fish demands your attention. The 

crystals, ranging from a five-by-four-foot fluorite from 

China to miniature “thumbnail” specimens in a display 

case, vary in size, shape, and geographic origin. “If 

you go around and look at every single crystal, they’re 

from all over the world,” said Dave Skelly, the Director 

of the Peabody Museum. Stefan Nicolescu, head of the 

Peabody’s minerology collections, guided the selection 

of minerals, consulting private collections throughout 

the region and selecting specimens for their wow factor. 

“The interest is to stir curiosity and to make people want 

to know more about these things,” said Nicolescu. 

The recent ribbon cutting ceremony thoroughly 

explored this theme of curiosity and inspiration: “The 

goal is to capture people’s imagination, particularly the 

imaginations of budding young scientists, to get them 

fascinated by the natural world,” said Jay Ague, chair of 

Yale’s Geology and Geophysics department. They hope 

to reach far beyond New Haven. Since its conception 

150 years ago, the Peabody Museum has served as the 

archetype for many natural history museums. The 

curators of the David Friend Hall hope that their setup 

will also set an example that diffuses globally. 

For New Haven residents and Yale University students, 

the hall breathes new life into an already brilliant 

collection of natural history. “I think this exhibit will 

certainly bring more students up [to the Peabody],” 

said Dean Jonathan Holloway. The brilliant jewels may 

prompt curiosity for understanding our world. 


December 2016 


25

FEATURE 

human evolution 

THE EXISTENTIAL CRISIS OF THE 

FEMALE ORGASM 

►BY KRISSTEL GOMEZ 

The female orgasm has always provoked biologist’s curiosity. 

From an evolutionary perspective, the male orgasm has a 

clear purpose: it is required for ejaculation and the subsequent 

transfer of sperm. Explaining the female orgasm is more difficult, 

since fertilization and reproduction will occur whether 

or not a female orgasm occurs. In fact, female orgasms occur 

more frequently during masturbation or homosexual intercourse 

than during heterosexual intercourse. Natural selection, 

the driving process of evolution, favors traits that yield a 

survival or reproductive advantage to a species, so why has the 

female orgasm evolved if it provides no apparent survival or 

reproductive advantage? 

Yale’s Günter Wagner and his colleague, Mihaela Pavlicev, 

recently identified that the female orgasm—like the male orgasm—predates 

the primate lineage. Thus, the human female 

orgasm likely evolved from an older, functional trait and was 

passed down through generations. Here, we will explore the 

history of this trait and how its function has changed since it 

originated. 

For species whose ovulation is induced by copulation, it is 

thought that orgasms stimulate the release of hormones such 

us prolactin and oxytocin, triggering ovulation. In contrast, 

women are spontaneous ovulators. Although they too release 

prolactin and oxytocin during orgasm, their ovulation cycles 

do not depend on these hormones. 

Differences in ovulation cycles between species may have 

evolved in tandem with anatomical differences. Wagner’s 

study predicted that for spontaneously ovulating animals, the 

distance between the clitoris and the vaginal opening can be 

larger than for animals with copulation-induced ovulation, 

whose clitorises should be within (or near) their vaginal openings. 

In accordance with this prediction, external, non-penile 

stimulation of the clitoris is required for many women to 

achieve orgasm, because the clitoris is relatively far from the 

vaginal canal. 

Looking deeper into anatomical evolution, Wagner and his 

colleague studied databases of veterinary literature comparing 

female animal anatomy. In spite of a dearth of accurate studies 

on female genitalia, they found enough data to support 

their hypothesis. They discovered that in most species of reptiles, 

birds, and mammals, a single canal is used for urination 

and copulation. In these animals, the clitoris is often within or 

nearby the copulatory canal. However, in the ancestors of humans 

and other primates, the urogenital canal–the canal used 

for urination and copulation–shortened until the urethra became 

an entirely independent canal. As these two canals separated, 

the distance between the copulatory canal and the clitoris 

also increased. 

Wagner realized copulation-induced ovulation occurred 

most often in animals in which the clitoris was located within 

or near the copulatory canal. Spontaneous ovulators, in contrast, 

evolved to separate the clitoris and vagina. Together, 

this information suggests that the common ancestor of many 

mammals was a copulation-induced ovulator. However, as 

spontaneous ovulation evolved in humans and primates, clitoral 

stimulation as a means to induce ovulation became useless, 

and evolution distanced the clitoris from the copulatory canal. 

Though researchers have yet to prove that copulation-induced 

ovulation is triggered by clitoral stimulation and orgasm, 

the theory is pharmacologically testable. Future studies 

could use drug-induced anorgasmia–the inability to achieve 

orgasm–and the subsequent monitoring of an animal’s ovulation 

cycle, to begin to answer this question. 

In the context of spontaneous ovulation, clitoral stimulation 

leading to female orgasm may serve another purpose. For example, 

orgasm might improve pair bonding. Wagner emphasized 

that, although the female orgasm may not make a clear 

contribution to reproductive fitness, this does not reflect its 

modern importance. “Maybe the way to think about the female 

orgasm is as a type of art . . . which doesn’t have to have 

a specific purpose but still has value,” Wagner explained, referencing 

the way we value our ability to admire art despite its 

non-existent connection with reproduction or fitness. 

Wagner’s research has powerful and liberating implications 

for both men and women, freeing them from preconceived 

notions about the meaning of female orgasm during heterosexual 

intercourse. The research will hopefully discourage unhealthy 

notions, such as Sigmund Freud’s labeling of the clitoral 

orgasm as “infantile,” or theories that claim the female 

orgasm occurs more frequently with higher-quality males as 

a mechanism for retaining larger quantities of their sperm. 

Wagner and Pavlicev explain the difficulties associated with 

achieving female orgasm during heterosexual intercourse as 

an effect of evolution without any intrinsic implications regarding 

the male’s value. 


►The female orgasm releases the hormones prolactin and 

oxytocin, which are theorized to trigger ovulation and fertilization. 


materials science 

FEATURE 

PLASTIC PREYS ON DEEP-SEA 

ORGANISMS 

►BY DIANE RAFIZADEH 

IMAGE COURTESY OF WIKMEDIA COMMONS 

►Marine debris, the result of human plastic waste, on the 

beaches of Dar es Salaam, Tanzania. These large plastic 

pieces are shredded by weathering into more dangerous, easily 

ingestible microplastics. 

The dangers of oceanic plastic pollution are well known: 

throughout social media, trending videos portray turtles 

trapped in plastic netting and decomposed birds with 

plastic in their stomachs. The reality of plastic pollution is 

heart-wrenching, and researchers are continuously producing 

more evidence to demonstrate the extent of the problem. 

Discoveries from the past 20 years have revealed that organisms 

living in shallow waters and the middle layers of 

the ocean ingest copious amounts of plastic. Most recently, 

however, researchers at the University of Oxford discovered 

that deep-sea organisms—rarely studied in this context until 

now—are also consuming plastic at alarming rates. Their 

finding is particularly concerning because it demonstrates 

the vast impact of human plastic pollution: our trash has 

reached one of the Earth’s most remote and fragile environments. 

Conducted primarily by Michelle Taylor and Lucy Woodall 

at Oxford, the research concentrates on microfibers, the 

most common type of microplastic found in the environment. 

Microplastics are small plastic pieces, usually less than 

five millimeters in diameter (the width of a thumbtack), that 

are created when larger plastic debris is weathered and broken 

apart, while microfibers are a sub-class of fiber-shaped 

microplastics that often come from fibers on clothing. They 

are particularly dangerous for aquatic wildlife because they 

can easily get trapped in an animal’s digestive track or gills, 

lessening its feeding ability, damaging its digestive track, and 

often leading to its starvation. Organisms also face contamination 

by concentrated organic pollutants and metals that 

are harbored by the plastics. 

Taylor and Woodall’s research was inspired by earlier findings 

that discovered microplastics in deep-ocean sediments. 

“We were discussing what deep-sea animals eat, which is 

mostly particle matter falling from shallower waters—something 

called marine snow, and if this snow would have microplastics 

in it,” said Taylor, a senior postdoc at Oxford. 

The researchers explored deep-sea organisms in the equatorial 

mid-Atlantic and southwest Indian Ocean by sending 

a robot to the seafloor to scoop up organism samples. Reaching 

such depths was a major challenge, but the research team 

had access to a UK research ship and the Remote Operated 

Vehicle Isis robot, which can reach depths of 6000 meters. 

From their collected samples, they studied three distinct 

phyla: Cnidaria (such as jellyfish and corals), Echinodermata 

(such as starfish and sea cucumbers), and Arthropoda (such 

as crustaceans). The researchers recorded the depth where 

each organism was found, the type of microplastic it had interacted 

with, and the microplastic’s location on or within 

the organism. Most of the studied organisms, such as squat 

lobsters, corals, and sea cucumbers, contained microplastics 

in their oral areas, stomachs, and gills, indicating that 

the plastics were either ingested or inhaled. For example, the 

researchers found microplastics made of polypropylene, a 

polymer that can carry compounds such as DDE, a pesticide. 

The logical follow-up question is what we can do about human 

plastic pollution, but the answer is difficult because of 

the sheer prevalence of plastics in daily life. “It’s surprising 

how much clothing we wear is made up entirely of acrylic or 

polyester—I challenge you to check yours now,” said Taylor. 

Scientists are currently designing safer plastics. Paul Anastas, 

the Director of Yale’s Center for Green Chemistry and 

Green Engineering, says research should focus on developing 

biodegradable plastics that do not persist in the environment. 

“There is a worldwide network of people producing 

these solutions, and they need to be implemented much 

more rapidly.” The twelve principles of green chemistry include 

designing safer chemicals, using safer solvents, and reducing 

energy use. 

Governments, too, are taking measures to reduce the 

amount of plastic waste released into marine environments. 

In December of 2015, President Obama signed the Microbead-Free 

Waters Act, banning the cosmetics industry from using 

plastic microbeads, such as the exfoliating beads in facial 

soaps that are washed down the drain and released into the 

ocean. 

The public also has a responsibility to keep plastics out of 

our oceans. We can trash the “throw-away” mentality that 

leads us to use disposable plastic cups and utensils and opt 

for reusable options like cloth bags at the grocery store. In the 

meantime, Taylor hopes to see further research that probes 

deep-sea plastic pollution. 


December 2016 


27

FEATURE 

medicine 

insight into 

EYESIGHT 

REAWAKENING RETINAL STEM CELLS 

by CHRISTINE XU 

art by YANNA LEE 


A 

lizard escaping from a predator can lose its tail as a defense 

mechanism—while the detached tail writhes on the ground 

and confuses the predator, the lizard scurries away. During 

the following months, the lizard grows back a new tail. How does 

this regeneration occur? The answer lies in the behavior of stem 

cells, specialized cells that can both renew themselves and generate 

various other cell types. 

Humans have stem cells, too, although they behave differently 

from those in the lizard’s tail. Many distinct populations of stem 

cells reside within each of us. Neural stem cells in our brains, for 

instance, can become new neurons or glial cells. Blood stem cells 

in our bone marrow can turn into new white blood cells, red blood 

cells, or platelets coursing through our bloodstream. Since stem cells 

are extremely versatile and can generate a number of new cell types, 

a recent goal of researchers and clinicians has been to harness their 

regenerative abilities for replacement therapies—restoring lost organs 

and tissues in human patients. 

Bo Chen, associate professor of Ophthalmology at Yale, studies 

human retinal stem cells. Recently, his team figured out how to 

reawaken the stem cell ability of a special group of dormant cells, 

called Muller glial cells (MGs). MGs are found in the retina, a tissue 

at the back of the eye that detects visual information in the form of 

light. While MGs in humans are not true stem cells, they can behave 

like stem cells under certain circumstances, such as extreme injury. 

MGs are normally asleep, in an inactive state, but injury can reawaken 

them and cause them to reenter the cell cycle and develop regenerative 

stem cell abilities. Chen and his research team discovered 

how to wake up MGs and cause them to proliferate without injuring 

them, a strategy that could potentially help to restore retinal cells 

damaged by disease. 

In invertebrates, such as zebrafish, MGs are permanently active 

retinal stem cells capable of regenerating damaged and lost cells. In 

mammals, however, MGs typically remain dormant and incapable 

of spontaneously re-entering the cell cycle without outside intervention. 

While past studies have shown that severe retinal injuries 

can stimulate MG proliferation and stem cell activation, Chen found 

that injuring MGs was counterproductive to the goal of regeneration. 

“We wanted to do something different: activating these cells 

without inflicting any damage to the retina. Our goal was to make 

neurons without having to kill any neurons in the first place,” Chen 

said. 

The cell’s decision to remain dormant or become active depends 

on a network of signaling pathways that is poorly understood. 

Chen’s team suspected that the Wnt signaling pathway was involved, 

since this pathway is also involved in embryonic development and 

the regulation of stem cell behavior. Thus, the researchers decided 

to test if they could reawaken MGs by increasing the activity of the 

Wnt pathway. 

In the traditional signaling pathway, Wnt proteins bind to cell receptors 

to initiate a cascade that eventually results in inhibition of 

the GSK3 protein. GSK3 normally degrades β-catenin, a signaling 

molecule that causes a number of cellular effects. Therefore, when 

the Wnt signaling pathway is activated, GSK3 is inactivated and 

β-catenin accumulates inside the cell. The increase in β-catenin then 

turns on a set of genes that can change the activity of the cell by 

promoting proliferation. To study how Wnt signaling affects MGs, 

Chen’s team used viruses to transfer the β-catenin gene into mouse 

MG cells, thus mimicking the effects of an activated Wnt pathway. 

medicine 

FEATURE 

After the team transferred the β-catenin gene into the cells, a 

significant number of MGs began to reenter the cell cycle and proliferate. 

To confirm the role of β-catenin, the researchers next deleted 

the GSK3 gene, which encodes for the protein that degrades 

β-catenin—again causing a buildup of β-catenin. Once again, they 

observed significantly increased proliferation of MGs. They also 

discovered that β-catenin directly affected the expression of a gene 

called Lin28, which has been shown to regulate stem cell decisions. 

Chen’s team had made a remarkable discovery, being the first 

to activate the proliferative response of MGs without retinal injury. 

Now that they were capable of waking up MGs, they wanted to 

know whether their reactivated MGs were behaving like true stem 

cells—that is, whether the MGs were capable of generating other 

cell types. They transferred the β-catenin gene to a population of 

MGs and gave them time to activate and differentiate. When they 

analyzed the gene expression of the MGs, they found that the reactivated 

MGs expressed similar genetic profiles to several retinal cell 

types, suggesting that the MGs were able to differentiate in a stemcell-like 

manner. 

The impact of Chen’s study lies in its implications for stem cell 

regenerative therapy. “Stem cell therapies are promising for treating 

diseases of the human retina, where there is a loss of retinal cells,” 

Chen explained. These diseases include macular degeneration and 

glaucoma, both of which cause vision problems and can eventually 

lead to blindness. If stem cells could be used to regenerate lost retinal 

cells, then scientists and clinicians would have a novel tool to 

treat these types of degenerative retinal diseases. “We can activate 

this group of MG cells and potentially direct their differentiation 

into any type of retinal neurons, which could replace lost cells. Essentially, 

we are asking our retinas to repair themselves,” Chen said. 

Although the preliminary results are promising, Chen and the 

other scientists still do not fully understand the complex process of 

MGs differentiation. For instance, the researchers still do not know 

how reactivated MGs choose to become one cell type or another. 

“The challenge now is that even when the MGs reenter the cell cycle, 

they might not make the exact type of neuron we want,” Chen 

said. He would like to better understand the signaling pathways that 

guide MG differentiation in order to produce the cell types required 

for regenerative therapy. In the future, Chen would like to test different 

sets of factors that control MG differentiation. “We hope to use 

these factors to guide the differentiation of the reactivated MGs to 

make the types of cells that we want.” 

Chen and his team are currently focusing on two types of neurons: 

photoreceptor cells and ganglion cells. Both cell types are extremely 

important in eyesight, detecting light from the environment and 

converting it into electrical signals that can be routed to the brain. 

If scientists such as Chen’s team successfully produce new photoreceptor 

cells and ganglion cells from MGs, then these cell types could 

be restored in patients who have lost them due to injury or disease. 

Retinal stem cells are an important research topic, and Chen’s findings 

will be extremely valuable for other researchers in the field. For 

the first time, retinal cells regained stem cell abilities without injury. 

As the discovery improves our understanding of the fundamental 

signaling pathways behind stem cell differentiation, researchers 

could soon harness the abilities of stem cells to heal damaged tissues 

in patients. Chen is optimistic that other scientists will continue to 

build upon his findings. “This type of research will ultimately greatly 

benefit patients if we are successful,” he predicted. 


December 2016 


29

SUPERBUGS 

SEE 

STARS 

by Grace Niewijk || art by Anusha Bishop 

“We talk about a pre-antibiotic era and an antibiotic era. If we’re not careful, we will soon be in a post-antibiotic era. 

And, in fact, for some patients and some microbes, we are already there.” 

- Tom Frieden, CDC Director 

Scientists predict that, without a major pharmacological breakthrough, 

deaths from antibiotic-resistant bacteria will surpass 

cancer deaths by the year 2050. However, thanks to a team from 

the Melbourne School of Engineering, that breakthrough may be a bit 

closer. The team designed tiny, star-shaped polymers that were highly 

effective against multiple types of bacteria without allowing resistance 

development. Though more testing and development is required, scientists 

are hopeful that these polymers could avert a deadly global 

health crisis. 

Just as humans can build up tolerance to poisons by exposing themselves 

to incremental, sub-lethal doses over time, bacterial colonies 

can develop resistance to antibiotic drugs when exposed to non-lethal 

quantities. Although the biological processes are different, the result is 

the same: substances that would normally prove lethal suddenly fail to 

have an effect. In the case of antibiotic-resistant bacteria, this can mean 

infections and diseases that were once easily treated suddenly become 

deadly. Without antibiotics, even routine procedures like kidney dialysis, 

appendectomies, hip replacements, and biopsies would suddenly 

carry extremely high risk. 

Manisha Juthani-Mehta, an infectious diseases physician at the 

Yale School of Medicine, notes that drug-resistant bacteria have been 

around for decades, but modern medicine is exacerbating their proliferation. 

“We have far more [drug-resistant bacteria] now with prevalent 

overuse of antibiotics,” she said. The agricultural industry is by far 

the largest culprit of overuse, purchasing 80 percent of all antibiotics 

sold in the United States every year. The drugs help promote plant and 

livestock growth and protect crops and animals from diseases. While 

these uses are important, they are not so crucial that cutting back 

would be impossible. Overuse drastically increases the rate at which 

drug-resistant bacteria develop and spread in the environment and in 


iomedical engineering 

FEATURE 

the food supply. Nursing homes and hospitals are other major breeding 

grounds for antibiotic-resistant bacteria. “In nursing homes, infections 

are commonly suspected and antibiotics are frequently prescribed. 

Older nursing home residents have multiple medical problems and are 

often exposed to multiple rounds of antibiotics” said Juthani, whose 

expertise involves infections in older adults. Although scientists and 

government agencies have encouraged farmers and medical professionals 

to limit antibiotic use, no strict regulations have been passed. 

For some infections, we are running out of treatment options. “We 

are more often stuck using very toxic, old antibiotics because we have 

no choice,” said Juthani. In some cases, even these last resorts are failing. 

Each time a bacterial infection becomes resistant to a particular 

drug, physicians can only hope that a new, more effective drug will 

be developed. Unfortunately, because bacteria generally develop resistance 

to a drug very quickly and thereby render it obsolete, antibiotic 

development is not profitable for pharmaceutical companies. “There 

have only been one or two new antibiotics developed in the last 30 

years,” said Greg Qiao from the University of Melbourne in a Science 

Daily article. 

That’s where the real stars come in. A team of Australian scientists— 

including Qiao, Eric Reynolds, and PhD candidate Shu Lam—recently 

published a paper in Nature Microbiology describing a promising alternative 

technology to combat multidrug-resistant bacteria. Instead 

of designing a traditional chemical drug treatment, the team developed 

what they call “structurally nanoengineered antimicrobial peptide 

polymers,” or SNAPPs, for short. The researchers were inspired 

by natural antimicrobial peptides, which are small proteins that play 

important roles in the immune systems of many organisms. Naturally 

occurring antimicrobial peptides cannot be used in clinical settings 

because they are often toxic to mammalian cells, but Lam and her 

team wanted to use them as a model for designing a powerful and safe 

antibiotic agent. 

The scientists meticulously designed the polymers down to the level 

of the individual building blocks—amino acids—that would make up 

the peptides. Out of the many amino acids available to them, the scientists 

chose lysine and valine. Lysine is a positively charged cation and 

was selected because cationic peptides were already known to exhibit 

antimicrobial activity. Valine, on the other hand, is uncharged and 

therefore hydrophobic, meaning it does not interact favorably with 

water or other polar molecules. Since hydrophobic materials interact 

favorably with other hydrophobic materials, valine’s hydrophobicity 

enables the SNAPPs to infiltrate the cell membrane, which is also 

mostly hydrophobic. Instead of just creating long chains of amino acids 

or allowing the polymers to self-assemble, the researchers attached 

groups of 16 or 32 chains to a multifunctional core, which served to 

promote water solubility and create the characteristic star shape. They 

hypothesize that the star shape optimizes functionality because it promotes 

peptide aggregation and localized charge concentration, which 

leads to more effective ionic interactions with bacterial membranes. 

After designing and successfully producing the polymers, the researchers 

assessed the activity of the SNAPPs against different species 

of bacteria. The SNAPPs were active against all bacterial species but 

were especially effective against Gram-negative bacteria, such as E. 

coli. Gram-negative bacteria are characterized by an outer membrane 

that normally acts as a highly impermeable barrier, but the researchers 

discovered that the SNAPPs could penetrate this membrane, since 

they have a high affinity for specific molecules found on it. The treatment 

was equally effective against antibiotic-resistant and susceptible 

strains of bacteria. The effectiveness of SNAPPs against Gram-negative 

bacteria is especially important because no antibiotic drugs currently 

under development are effective against Gram-negative infections. 

Before testing SNAPPs in living organisms, the researchers first performed 

a biocompatibility assay to ensure that the polymers would 

not attack mammalian cells. By incubating the polymers with sheep’s 

blood and measuring death rates of blood cells, the scientists determined 

that SNAPPs exhibit very low toxicity, even at concentrations 

100 times higher than what is required to kill bacteria. After confirming 

biocompatibility, they tested the effectiveness of SNAPPs by 

treating mice with rampant bacterial infections. The results were very 

promising—all mice treated with SNAPPs lived, compared to only 

20 percent of the untreated mice. In addition, SNAPP treatment enhanced 

the ability of white blood cells to infiltrate infected tissues, a 

benefit not displayed by mice treated with traditional antibiotics. 

The SNAPPs have multiple mechanisms of killing cells, making it 

more difficult for bacteria to develop resistance against them. The 

polymers’ partially hydrophobic composition allows them to infiltrate 

the membrane, but once they have done so, the positively charged 

amino acids disrupt membrane integrity and prevent regulation of ion 

flow. The star-shaped polymers can even aggregate and rip apart the 

membrane. The SNAPPs may also trigger the cellular processes that 

induce apoptosis, or cell suicide. All these mechanisms of antibiotic 

action are impressive individually, but when combined in a single molecule, 

they are incredibly powerful and difficult for bacteria to fight. 

Even after exposing 600 generations of bacteria to low concentrations 

of SNAPPs, the researchers could not detect bacterial resistance to the 

treatment. These results show great promise for SNAPPs as a longterm 

solution to the rise of superbugs. 

To bring treatments like SNAPPs into regular use, more research, 

development, and eventually clinical trials are needed. Although many 

industries and the public still fail to heed scientists’ warnings about antimicrobial 

resistance, governments and research institutions are starting 

to focus on the war against drug-resistant bacteria. On September 

21st, the United Nations held a summit on antimicrobial resistance 

and concluded that all countries must formulate a plan to combat it. 

At the beginning of October, the CDC announced that a Yale School of 

Public Health research team—along with 33 other teams—will receive 

funding as part of a $14 million effort to research antibiotic resistance. 

Hopefully, this collaboration between scientists and governments will 

allow SNAPPs—and perhaps other new technologies—to better aid in 

humanity’s battle against antibiotic-resistant bacteria. 


►Scanning electron micrograph image of methicillin-resistant 

Staphylococcus aureus (MRSA). MRSA is one of the most well-known 

drug-resistant bacteria and is especially common in hospitals and 

sports settings. 


December 2016 


31

FEATURE 

astronomy 

SHEDDING LIGHT ON A 

BIZARRE 

STAR 

BY THEO KUHN 


From space, most stars never twinkle. Some dim periodically, betraying 

the clocklike passage of planets. But there is one star that flickers 

unlike any other seen before. Known as “Tabby’s Star,” this astronomical 

enigma has captured the imaginations of thousands of scientists 

and amateurs alike. Its mysterious blinking behavior was first spotted 

by amateurs and was subsequently investigated by former Yale postdoctoral 

fellow Tabetha Boyajian ’16. Because the behavior of Tabby’s Star 

is completely unlike that of similar stars, scientists have resorted to an 

array of wild theories as potential explanations—from a massive comet 

chain to an alien megastructure. New research suggests that the star is 

even more peculiar than previously thought, complicating attempts to 

explain its behavior and reinforcing the need for continued study of its 

idiosyncrasies. 

Tabby’s Star (more formally known as KIC 8462852, and more colloquially 

as the “WTF”—Where’s The Flux?— Star) was observed from 

2009 to 2013 by NASA’s Kepler Space Observatory. This orbiting telescope 

is designed to detect the shadows of exoplanets as they pass in 

front of stars. But because of its foreign behavior, Tabby’s Star was not 

detected automatically; it took the relatively untrained eyes of citizen 

scientists—amateur astronomy enthusiasts who volunteered to pore 

through Kepler’s data with their own eyes—to spot the bizarre signal. 

“When they first showed the data to me, I just thought it was bad data”, 

Boyajian said. “Our automated pipelines missed this feature because it 

was unlike anything we had seen before,” she added. 

So just what is it about Tabby’s Star that is so perplexing? Most stars 

exhibit small, periodic, and symmetrical dips in their brightness, if they 

exhibit observable periods of dimness at all. These dips are the result of 

the regular passage of an orbiting planet in between the star and the telescope, 

a planetary eclipse of sorts. But research by Boyajian demonstrated 

that Tabby’s Star exhibits frequent and irregular dips in its brightness 

too large to be caused by a planet. New research led by postdoctoral researcher 

Benjamin Montet of the University of Chicago revealed another 

feature not seen in any nearby or similar stars: a dramatic, long-term 

dimming over the four-year course of the Kepler study. 

The sum of these observations leads to a troubling but fascinating dilemma: 

nothing like Tabby’s Star has been seen before, and no single 

theory can make sense of all of the star’s unique characteristics. “There is 

no good explanation for what’s going on,” Boyajian said. All explanations 

must involve an event far larger than anything of its kind seen before, 

or a controversial phenomenon that has been theorized but never observed. 

One of the favored explanations presented by Boyajian’s team 

consists of a comet swarm around the star that causes its fluctuations 

in brightness; however, all comet swarms observed so far are hardly a 

tenth of the size that would be necessary to produce such a large signal. 

The most well-known explanation for the star’s behavior is an energy 

harvesting system built by extraterrestrial life (known as a Dyson sphere 

or Dyson swarm). That said, any theory of such elaborate proportions, 

particularly one based on phenomena that have yet to be observed, must 

be regarded with suspicion. 

When Kepler refocused in 2013 on a new mission, it appeared that 

researchers would have to rely on only four years of data to solve this 

astronomical Rubik’s cube. But once again, astronomy enthusiasts came 

to the rescue: a Kickstarter project initiated by Boyajian raised over 

$100,000—enough to fund a year of constant observation of the star 

through Las Cumbres Observatory Global Telescope Network. With 

continuous monitoring of Tabby’s Star at multiple wavelengths, Boyajian’s 

team will be able to observe long-term trends. They will also be able 

to react in real time to short-term changes in the star’s intensity, which 

astronomy 

FEATURE 

wasn’t possible during the Kepler observations. Sudden changes will set 

off a “real-time trigger” that will cue the team to take a burst of higher 

resolution images, allowing them to better capture unprecedented rapid 

fluctuations in the star’s brightness. Subsequent analyses of these images 

have the potential to shed light on the cause of these fluctuations. 

While conclusions regarding Tabby’s Star are pending further observation, 

one message has already manifested: citizen science is a force 

with which to be reckoned. The discovery of Tabby’s Star and its continuing 

observation are the result of the massive amount of support that 

astronomy enthusiasts can provide; in addition being tracked by the 

global network of professional telescopes, Tabby’s Star will be monitored 

by the American Association of Variable Star Observers (AAVSO), an 

organization comprised primarily of amateurs. 

There are, of course, limitations to citizen science in the realm of astronomy. 

AAVSO is providing observations of Tabby’s Star to Boyajian’s 

team, collected by the home-operated telescopes of astronomy enthusiasts. 

Though these observations are useful, they are not as sophisticated 

or coordinated as those provided by a professional network. While this 

data may prove to be a helpful supplement, AAVSO is unable to provide 

a “real-time trigger” in the way that the Las Cumbres Observatory Global 

Telescope Network can. The numerous observation stations operated 

by AAVSO are not entirely standardized. As a result, observations from 

one station are systematically offset from others, precluding the use of 

AAVSO to identify short-term fluctuations. 

But what citizen science lacks in finesse, it makes up for in both manpower 

and willpower. “We were quite surprised by how many people 

were interested in supporting this project,” Boyajian said. Unlike many 

citizen scientist projects that rely on the human brain’s exceptional 

ability to recognize patterns in images— ‘pretty pictures,’” as Boyajian 

termed it—signing up for the Kepler project guaranteed hours of staring 

at graphs. That didn’t stop over 300,000 citizen scientists from contributing 

to the project and from being the first to spot this bizarre star. “Not 

a lot of astronomers take advantage of this immense resource,” Boyajian 

said. “I can definitely see citizen-science like this growing in the future.” 

IMAGE COURTESY OF WIKIMEDIA 

►A theoretical diagram of Dyson Rings, an extraterrestrial energy 

harvesting device that has been proposed as a possible, albeit farfetched, 

explanation for the observations of Tabby’s Star. 


December 2016 


33

COUNTERPOINT 

TIGHT JEANS? DON’T BLAME YOUR GENES 

►BY LUCINDA PENG 

The prevalence of obesity and Type 2 diabetes has been increasing for 

at least 50 years. Attempting to explain this trend from an evolutionary 

perspective, researchers developed the “thrifty gene hypothesis”: the 

idea that evolution selected for genes that promote fat storage as an 

evolutionary advantage during famines. 

The hypothesis originated in 1962, when James Neel proposed that 

modern living conditions had created an evolutionary mismatch, 

which occurs when genes that once were advantageous become 

deleterious in a new environment. He concluded that this mismatch 

had contributed to an increase in Type 2 diabetes, and his hypothesis 

was the first widely discussed idea on the subject. However, in 1989, 

Neel reviewed his own work and realized that his hypothesis was 

probably incorrect, for famines occurred too infrequently to have 

generated significant selection pressure. Since then, the theory has 

been put aside in favor of other hypotheses, and the new results 

discussed below solidify that move. 

Guanlin Wang and John Speakman of the Chinese Academy of 

Sciences found genetic evidence opposing the thrifty gene hypothesis. 

They examined 115 single nucleotide polymorphisms (SNPs), or 

common genetic mutations, that had previously been found to be 

correlated with obesity. They used genomes from a database compiled 

by the 1000 Genomes Project, an international collaboration to 

document genetic variability among different ethnicities, to ensure 

that effects of specific subpopulations did not influence their results. 

When Wang and Speakman analyzed the SNPs associated with a 

higher body mass index (BMI) in obese and control populations, they 

found no significant selection for these genes, suggesting that evolution 

has not selected for obesity. In fact, of the nine genes associated with 


►Calorie dense junk food has contributed to the rise of type 2 

diabetes and obesity. 

BMI, five of them had decreased, rather than increased, fat storage. 

Their discovery is not consistent with the genetic basis of the thrifty 

gene hypothesis, increasing the plausibility of other theories about 

the underlying causes of obesity. Dr. Stephen Stearns, Yale professor 

of Ecology and Evolutionary Biology, cites two other hypotheses to 

replace the thrifty gene hypothesis: the thrifty phenotype and the 

hygiene hypotheses. 

Hales and Baker proposed the thrifty phenotype hypothesis in 1992, 

suggesting that the body uses information from the environment 

early in life to predict its needs for the future environment. These 

environmental conditions can induce epigenetic changes, or 

nongenetic mechanisms, that affect phenotypic (observable) traits. 

They found that babies born during the Dutch Hunger Winter, a 

six-month food blockade by the Germans in the Netherlands, were 

more prone to insulin resistance due to a nutritional deficit in the 

womb. Insulin promotes the absorption of sugar from blood into 

tissues, but under starvation conditions, nonessential tissues become 

less responsive to insulin so that the brain can receive enough sugar. 

When the Germans left, food was abundant, so the environment that 

the baby was prepared for did not match the environment it was born 

into. As a result, the people born in this period were more prone to 

diabetes and other diseases. “This trend can be observed under normal 

circumstances, too, as birth weight is a good predictor of the risk of 

being affected by diseases later in life,” said Dr. Stearns. The thrifty 

phenotype hypothesis addresses a major problem from the thrifty 

genotype hypothesis. If there had been continued, strong positive 

selection for increased fat storage, all humans would be obese because 

these genes would be fixed, or permanently added to the human 

genome. In contrast, with “thrifty phenotypes,” epigenetic factors are 

affected by the environment and can vary among people. 

The hygiene hypothesis relates the gut microbiota to metabolic 

diseases. The gut microbiota is composed of bacteria that help to 

break down macromolecules and absorb nutrients; it is sensitive 

to environmental stimuli. For example, babies born by C-section 

rather than vaginal birth have different microbiota because they were 

not exposed to the bacteria in their mother’s birth canal, and being 

breastfed or taking antibiotics can also affect a baby’s gut microbiota. 

These changes have been shown to affect their risk of obesity, insulin 

resistance, and Type 2 diabetes. 

With a lack of genetic evidence to support the claim that humans 

evolved to better store fat, the thrifty phenotype and hygiene hypotheses 

are now favored to replace the thrifty genotype hypothesis. Wang and 

Speakman’s paper provides more concrete evidence to refute the thrifty 

gene hypothesis, supporting what many scientists already believed. 

Because the thrifty phenotype and hygiene hypotheses explain why 

metabolic diseases can be inherited but are also heavily influenced by 

the environment, they provide a more robust explanation for the rise 

in obesity and Type 2 diabetes. 


BLAST 

from 

the 

PAST 

Malaria: Finding the Missing Pieces of Malaria’s Migratory Patterns 

►BY WILL BURNS 

In 1925, Spain’s Catalan Government set up a humble 

hospital in the Ebro Delta region. The hospital treated 

patients suffering from malaria. Ildefonso Canicio, a 

doctor at the hospital, spent decades diagnosing and 

treating patients. By drawing blood from patients, 

and placing a drop on a microscope slide, he could 

determine whether the blood contained Plasmodium, 

the parasite that causes malaria. 

Canicio threw away most of his slides, but he kept 

a few slides from the 1940s. Little did he know that 

seventy years later, these slides would provide insight 

into the global migratory patterns of the malaria 

Plasmodium. 

To fight malaria in the present day, researchers are 

looking to the past to understand how the parasite 

evolved over time, specifically exploring how human 

movements transmitted the parasite across the globe. 

Malaria was successfully eradicated from Europe after 

World War II. Thus, researchers have had to search 

for old, badly preserved slides from Europe’s preeradication 

era, hoping to find clues about the nowextinct 

parasite. 

Carles Lalueza-Fox, a paleo-genomics researcher 

at the Institute of Evolutionary Biology in Barcelona, 

reached out to Canicio’s family who gave him three 

slides to analyze. Back at the lab, he quickly realized 

that analyzing the slides would be difficult. “There 

were just a few drops of blood in the samples. Once 

they were extracted and sequenced, they were gone. 

The slides were fragile and covered with stains and 

oils,” said Lalueza-Fox. 

Despite the fragility and small size of the samples, 

Lalueza-Fox and his team successfully obtained 

a huge amount of genetic data from Plasmodium 

mitochondrial DNA (mtDNA). Unlike nuclear DNA, 

mtDNA is inherited only from the mother, so it is 

better suited for determining the maternal lineage 

and genealogy of a species. “As far as I know, this is 

the first study where such old slides were used and 

such an amount of genetic data from the pathogens 

was retrieved,” Lalueza-Fox added. 

Using the reconstructed European Plasmodium 

mtDNA genomes, Lalueza-Fox and his team shed light 

on certain controversies surrounding the parasite’s 

evolutionary history. “It was not clearly understood 

how the pathogen spread along different continents, 

because Europe was central to some of these dispersals 

but no data from Europe was available,” noted Lalueza- 

Fox. 

His team found surprising genetic similarities 

between European Plasmodium mtDNA and Indian 

Plasmodium mtDNA. Lalueza-Fox believes that 

malaria was transmitted from India to Europe when 

the Persian Empire expanded into India in the sixth 

century BCE. 

The team also found evidence that European, 

Central American, and South American parasites 

are genetically similar–indicating that, the exchange 

of food, plants, culture, and technology between the 

Old World and the Americas in the 15th and 16th may 

have helped spread malaria. 

Lalueza-Fox is now attempting to construct the 

nuclear genome of the European Plasmodium 

parasite. “So far, we have about 40 percent of the 

nuclear genome of the P. falciparum. I reckon we need 

four or five more slides,” Lalueza-Fox said. 

In Lalueza-Fox’s opinion, understanding the 

nature of parasites from 100 years ago is critical for 

understanding the resistance of modern parasites to 

treatment. “Plasmodium is a very dynamic organism 

and very difficult to tackle because of these mutations,” 

Lalueza-Fox added. 

His team will continue to search for the missing 

pieces of the Plasmodium “puzzle,” researching the 

extinct parasite to enhance our understanding of 

malaria. 


December 2016 


35

UNDERGRADUATE PROFILE 

DEVIN CODY (SM’17) 

IT REALLY IS JUST ROCKET SCIENCE 

►BY ELIZABETH RUDDY 

Ten. Ten Yalies begin the countdown, holding their breath, 

praying. Nine. A lone rocket sits in an endless expanse of canyonfilled 

wilderness. Eight. They smile, their eyes never straying from 

Chronos, awaiting the culmination of their year of work. Seven. Six. 

The numbers fly, tumbling out of their mouths. Five. Four. Three. 

The exhilaration builds. Two. All they can do now is watch. One. 

Devin Cody, now a senior double majoring in Electrical 

Engineering and Applied Physics, remembers that day in June 

of 2014 clearly. The competition rocket team, a subset of the Yale 

Undergraduate Aerospace Association (YUAA), launched Chronos, 

a rocket which they had been developing for months, seven thousand 

feet into the air, earning second place at the Intercollegiate Rocket 

Engineering Competition. The objective of their launch was to test 

general relativity using two atomic clocks. They hoped that the clock 

in the rocket would tick slower (on the scale of ten trillionths of a 

second) relative to the clock on the ground due to time dilatation, 

a physics framework that dictates how time passes differently in 

different reference frames. Although the data from the clocks was 

ultimately inconclusive, the launch itself was successful. 

For Cody, launching Chronos was a thrilling experience. “It was 

exhilarating to see our rocket fly into the air at close to the speed of 

sound, just praying that the parachutes would deploy,” said Cody. 

Since the launch, he has become an active member of the YUAA. He 

served as one of the group’s co-presidents during his junior year, and 

he continues to serve as a senior advisor on their executive board 

this year. 

PHOTOGRAPHY BY GEORGE ISKANDER 

►Devin Cody serves as a senior advisor on the Yale Undergraduate 

Aerospace Association’s executive board. 

During his sophomore year, Cody was selected to lead a YUAA 

project to build a radio telescope. He drew on his experiences from 

the previous summer at the National Radio Astronomy Observatory 

in West Virginia, where he helped improve the accuracy of 

telescopes by developing code to both detect and correct errors and 

malfunctions. At Yale, Cody’s 16 person team designed and built an 

8 foot telescope, complete with a mount, receiver, and control code. 

“That was a really cool project for me because I got to work with 

some incredible engineers at Yale and with people who became some 

of my closest friends,” said Cody. The telescope currently sits on the 

roof of the Yale Leitner Observatory and Planetarium. 

Cody’s favorite research, however, was the work he did this summer 

with the Avionics and Hardware Engineering group of SpaceX, 

a private company currently pushing the boundaries of aerospace 

technology. SpaceX aims to bring down the cost of access to space by 

developing technology that will enable rocket reusability. At SpaceX, 

Cody developed an Electromagnetic Compatability (EMC) testing 

apparatus to test whether a coaxial cable provided adequate shielding. 

While he was there, Cody tested which shielding mechanisms were 

the most effective, research that was in great demand by members 

in other groups within SpaceX. “It was incredible seeing the impact 

that my work had almost immediately,” said Cody. “I think you 

realize your work matters when you have people from the other side 

of the company pushing you to get your work done fast because they 

need your results to make informed decisions about their work.” 

Well into his senior year at Yale, Cody is now exploring another 

passion, quantum computing. Together with Professor Michel 

Devoret, he is studying quantum bits (qubits) in order to determine 

their properties. Qubits are similar to regular computer bits— 

both are small units of data used to store information and execute 

instructions. However, qubits are used in quantum computers and 

are potentially capable of more efficient calculations. To investigate, 

Cody and a graduate student from Devoret’s lab are designing a 

computationally efficient method of optimizing qubit design. 

Devin Cody will graduate from Yale this spring with a double 

major in Applied Physics and Electrical Engineering and copious 

work experience at the National Radio Astronomy Observatory, 

SpaceX, NASA, and the Yale Quantum Institute. When asked about 

his plans for after Yale, Cody laughed. “It’s a valid question, I don’t 

have many answers just yet. I’m not entirely sure what I want to 

do… definitely electrical engineering.” But even within electrical 

engineering, Cody is certainly not tied to any one area, and it will be 

fascinating to see in which direction he chooses to launch. 


ALUMNI PROFILE 

DR. RALPH GRECO, M.D. ‘68 

CARING FOR THE CARETAKERS 

►BY ANUSHREE AGRAWAL 

Dr. Ralph Greco, a talented physician at Stanford Medical School, 

conducts research, but his biggest contribution to the field of medicine 

does not involve a pipette. Greco’s biggest contributions have 

been his improvements to the surgical residency program at Stanford. 

When asked about his motivation for researching resident wellbeing, 

Ralph Greco recites the chilling story of a promising student’s 

suicide. This incredibly talented man had graduated from the Stanford 

program and was completing further training in Chicago when 

he died. Greco recalls the memorial service he held in his house as 

particularly somber since the resident had left notes for his parents, 

recounting the verbal abuse he experienced daily from a surgeon in 

the program. 

The history of resident abuse can be charted back to a specific doctor 

from the 1800s. Greco cites surgeon William Stewart Halsted as 

the father of both the modern residency program and the cruelty 

associated with it. Greco’s theory is that Halsted’s implementation 

of the residency program at Johns Hopkins University had a basis in 

verbal abuse and authoritarian behavior, likely the result of his cocaine 

addiction. Because Halsted formally trained the first chairs of 

many medical schools, the cycle of abusive role models continued. 

After his resident died, Greco wanted to create a change and prevent 

further resident abuse. 

Greco, along with other esteemed academics interested in resident 

wellbeing at Stanford, began to break the cycle. Stanford was among 

the first institutions to implement a mandatory 80-hour workweek 

for residents: a precedent that other medical schools soon followed. 

He also created the Balance in Life program at Stanford—a program 

focused on promoting physical, psychological, professional, and social 

balance among residents through events, mentorships, healthy 

food and mental health initiatives. Since then, Greco has devoted 

the latter part of his career to improving the residency system, and 

he hopes to stop mentors from participating in abusive behavior targeted 

at residents. 

Not all medical professionals support Greco’s intentions, however. 

Greco recognizes that hospitals are reluctant to pour money into resident 

wellbeing—and into medical schools in general—because they 

want to maintain their efficiency. He has also had difficulty changing 

the mindset of doctors who once dealt with abusive behavior themselves. 

“Just as people who are abused sometimes become abusive 

parents, and learn to do that, this mindset becomes part of the upbringing,” 

Greco explains. The cycle is difficult to break. 

Greco has not limited himself to the pursuit of scientific endeavors. 

He is also an avid sculptor, and has been since he picked up the 

IMAGE COURTESY OF RALPH GRECO 

►Dr. Ralph Greco is a physician at the Stanford School of Medicine, 

where he has started the Balance in Life program to improve resident 

wellbeing. 

hobby at Princeton when an art teacher “took him under her 

wing.” Greco now considers stone his favorite medium. Art is extremely 

important to Greco, and he connects the activity to his focus 

on resident wellbeing. By pursuing his passion for art, he hopes to 

model a healthy work-life balance and show residents and doctors 

that they can make time for the hobbies that they love. He admits 

that finding this balance is difficult during residency, but creating a 

foundation for students to have a healthy mindset is critical. 

Greco cites Yale as an important place that opened doors for him 

as a physician scientist. He still talks with friends from medical 

school, and he continues to attend reunions. Greco plans to formally 

retire from Stanford next year, but he does not anticipate problems 

with his program after his retirement. He has already recruited the 

next leader of the program, and Greco is confident that she will continue 

working to educate residents and improve their lives at work. 

In retirement, Greco hopes to advance his artistic prowess and continue 

creating stone sculptures, although he does point out that stone 

is not the lightest material to work with. 


December 2016 


37

FEATURE 

book review 

SCIENCE IN THE SPOTLIGHT 

BOOK REVIEW: I CONTAIN MULTITUDES 

►BY SARAH ADAMS 

Until recently, microbes were primarily seen as carriers of sickness 

and disease. However, with technological advances and a few key 

discoveries that have highlighted their potential for medicine, microbes 

are now in the research spotlight. Ed Yong explores the nature of the 

close relationship between bacteria and animals in his new book I 

Contain Multitudes: The Microbes Within Us and a Grander View of 

Life. 

Yong begins by discussing the sheer ubiquity of microbes, thousands 

of which exist in the air, food, water, and even on this page. Then, he 

weaves a narrative that follows how microbes affect our bodies: how 

we maintain and manipulate our relationship with them, the benefits 

we reap from this relationship, and what happens when it fails. His 

chapter on horizontal gene transfer, the movement of genes from 

one organism to another without a parental-offspring relationship, 

was particularly interesting. He included an example of Bacteroides 

plebeius, a bacterium common throughout the world, and Zobellia 

galactanivorans, a bacterium found on seaweed. In the Japanese 

population, which consumes seaweed more regularly than the rest of 

the world, Zobellia has transfered the genes responsible for seaweed 

digestion to Bacteroides, which resides in the gut of the Japanese 

population. 

Yong also weaves an interesting narrative about the Wolbachia 

bacterium into the book. “Wolbachia is so fascinating because 

of how widespread it is and how it plays important roles in human 

PODCAST REVIEW: ARE WE THERE YET? 

►BY PAUL HAN 

disease,” said Yong. It is heralded as 

one of the most successful microbes 

on the planet because of its presence 

in 40 percent of insect and arthropod 

species. It originally did not have a 

practical medical application when it 

was first discovered but has recently 

been found to be able to potentially 

treat tropical diseases like the Dengue 

fever. “The whole story is a testament 

to science that does not have to have an 

immediate and practical application,” 

said Yong. 

In I Contain Multitudes, Yong 

IMAGE COURTESY OF ED YONG 

nods to past, notable discoveries in 

microbiology research, while incorporating examples of current 

research that connect to his themes. He also introduces a refreshing 

feeling of wonder—a feeling that is often ignored in books on 

similar topics—by highlighting the beauty of these microbial-animal 

interactions. “I wanted to get people to appreciate how interesting 

microbes are, rather than viewing them as sources of disease or dirt, 

to actually realize that they are important parts of the world around 

us. We should embrace that they are the dominant form of life on the 

planet with profound influences on the way life works,” said Yong. 

In popular science, few things are as romanticized as space exploration. 

It is the classic science fiction plot: the fearless captain and his loyal crew, 

journeying where no man has gone before. Yet to the average American, 

space exploration appears to be beyond our grasp, a distant, fanciful 

possibility in the drudgery of day-to-day life. 

A new podcast is hoping to change that perception. “Are We There 

Yet,” hosted by Brendan Byrne, follows the multifaceted efforts of 

interplanetary space travel, ranging from NASA’s New Horizons Probe 

to Elon Musk’s mission to Mars. Through informative discussion and 

interviews with the men and women at the forefront of space exploration, 

Byrne hopes to answer to question: “Are we there yet?” 

Byrne was inspired to start his podcast after researching NASA’s and 

other organizations’ plans to go to Mars. Byrne chose the podcast format 

over a traditional news segment so that he could explore his topics in 

greater detail. “I get the chance to really dig into these topics and not 

be constrained by time,” he explained. “I hope each episode inspires the 

listener to do some more exploring on their own.” 

Each week, Byrne introduces a topic, briefly shares his own perspective 

on the state and significance of the issue, and introduces his guest, 

whom he then interviews for the remainder of the podcast. His guests 

are typically scientists, researchers, and engineers from institutions such 

as NASA and Caltech’s Jet Propulsion Laboratory—all at the forefront of 

their field. They are courteous, intelligent, and highly informed. 

They are not, however, entertaining. While excellent sources of 

information, Byrne’s interviews are often dry and at times descend into 

jargon. While expert sources are an invaluable part of the show, the 

podcast would benefit from more speaking time for the host. When 

Byrne speaks, he immediately makes the subject more accessible. “I hope 

to take these insanely complicated technologies or plans and make them 

understandable,” he explained. He also understands the importance of 

public interest in the future of space exploration. “To succeed at space 

exploration, we need public support.” As a host, Byrne is excellent at 

exposing his listeners to these complicated technologies. He simply 

needs to put greater emphasis on making them accessible. 

While “Are We There Yet?” presents scientifically accurate and 

relevant information, it does not capture the audience’s imagination. 

There is promise, though. “We’re hoping to expand the show into a 

more produced and immersive experience,” he stated. If Byrne can 

execute his vision, “Are We There Yet” will be a compelling, entertaining, 

and informative program. Right now, however, it is more like a weekly 

fireside chat. For those captivated by the subject alone, however, this 

podcast is still worth a listen. 


cartoon 

FEATURE 

►BY ABHI MOTURI 

advertisement 

The Economy Doesn’t 

Affect Our Quality.

10% discount for all yale faculty and students 

call (203) 787-0400 or (203) 376-0356 

visit 50 Whitney Ave, New Haven, CT 06510

YSM Issue 90.1

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