Science & Technology

Poulos Studies Endangered Grass on Texas-Mexico Border

Pictured third from right, Helen Poulos, adjunct assistant professor of environmental studies, gathers with the “Fescue Rescue” team at Maderas del Carmen Protected Area in Mexico. There, the scientists are studying Guadalupe fescue, an endangered grass species.

field sites in the Sierra del Carmens, Coahila Mexico

Helen Poulos, adjunct assistant professor of environmental studies, works at a field site in the Sierra del Carmens, Coahuila Mexico. In September 2017, the U.S. government determined that Festuca ligulata needed protected species status and designated it a critical habitat under the Endangered Species Act of 1973.

The rare Guadalupe fescue once thrived in abundance atop mountains spanning the Texas-Mexico border, however, the desert-growing perennial grass is now so endangered, it only flourishes in two locations on Earth.

The rapid population decline is leaving scientists puzzled.

“Developing an effective recovery plan is essential for protecting Guadalupe fescue, however, the lack of basic information about this species’ ecology is a serious barrier to that goal,” explained Helen Poulos, adjunct assistant professor of environmental studies. “Urgent action is needed to stabilize the two extant populations.”

This summer, under Poulos’s leadership, Wesleyan received a National Park Service Grant to study Festuca ligulata through the Southwest Borderlands Resource Protection Program. She joined a bi-national team of scientists known as “Fescue Rescue” to research the two isolated fescue populations in Texas’s Big Bend National Park and the Maderas del Carmen Protected Area in Coahuila, Mexico.

Said Poulos, a plant ecologist who has worked at desert borderland sites for more than a decade, “The Guadalupe fescue has become so endangered that this has become a significant national and international conservation concern.”

Backed by the NPS grant, the Fescue Rescue team will conduct onsite visits from October to mid-November 2019 during Guadalupe fescue seed maturation. Seeds will be collected during this time and transported to labs at Sul Ross State University in Texas and Universidad Autónoma Antonio Narro in Mexico. At these locations, scientists will germinate the seeds and grow their own fescue refugial populations for multiple research purposes.

“Together, they’ll provide a springboard for future plant population genetics, enrichment planting, and adaptive management research on both sides of the border,” Poulos said. “Such information is vital for elaborating site-specific management plans for the species on both U.S. and Mexican soils.”

They’ll study environmental variables, inventory seed production, identify key factors that promote reproductive viability, and ultimately establish refugial populations on both sides of the border.

Although virtually nothing is known about the environmental influences on the growth and reproduction of Guadalupe fescue, Poulos believes the fescue’s population decline is a result of multiple factors.

“Environmental factors that have likely negatively influenced the fescue populations include a recent shift to a hotter and drier climate, the genetic and demographic consequences of small population sizes and isolation, trampling by humans and pack animals, trail runoff, competition from invasive species, and fungal infection of seeds,” she said.

In addition, naturally occurring wildfires, which play an important role in rejuvenating ecosystems, are rare due to livestock grazing in the early 1900s and subsequent direct fire suppression continuing to the present. The remaining plants in the two disjunct populations are likely highly inbred and lack genetic diversity. This can threaten the capacity of populations to resist pathogens and parasites, adapt to changing environmental conditions, and colonize new habitats.

Poulos hopes to deliver her final reports to the National Park Service by summer 2020.

Undergraduates Share Summer Research

poster session

Ben Sullivan ’20 presents his poster titled “Tracking New York Times Coverage of Every Senator First Elected in the 1990s” during the Summer Program for Research in the Sciences Poster Session on July 25. His advisor is Logan Dancey, associate professor of government.

The Summe Program for Research in the Sciences culminated with a research poster session in the lobby of Exley Science Center, with more than 100 students participating.

The program, held May 29 to July 26, was open to frosh, sophomores and juniors currently enrolled at Wesleyan. Wesleyan science faculty members served as mentors for student research in their laboratories. In addition to the closing poster session, the students participated in weekly seminars and workshops, a symposium, and various social events. After the poster session, students displayed their posters in the hallways outside the introductory biology laboratories.

Wesleyan in the News

In this recurring feature in The Wesleyan Connection, we highlight some of the latest news stories about Wesleyan and our alumni.

Wesleyan in the News
1. Inside Higher Ed: ‘Safe Enough Spaces’

President Michael Roth is interviewed about defending free speech, inclusion on campus, and affirmative action, among other topics, in connection with the forthcoming publication of his new book, Safe Enough Spaces: A Pragmatist’s Approach to Inclusion, Free Speech, and Political Correctness on College Campuses, due out Aug. 20 from Yale University Press.

2. The New York Times: “The World’s Smartest Chimp Has Died”

William Griffin Professor of Philosophy Lori Gruen writes in this op-ed about the legacy of the “world’s smartest chimp” Sarah, who died recently in her 50s after a long career working with researchers. Sarah taught the world about animal cognition, including chimps’ understanding of the thoughts and desires of others. Her career showed us that “not only do chimpanzees have complex thoughts, but also distinct personalities with strong preferences and prejudices,” Gruen writes.

Wesleyan’s Girls in Science Summer Camp Gets Young Scientists Excited about STEM 

GIS

Marty Gilmore, the George I. Seney Professor of Geology, professor of earth and environmental sciences, leads an experiment about meteors during the Girls in Science Summer Camp Aug. 8. (Photo by Kerisha Harris)

(Story by Kerisha Harris)

For the sixth year in a row, the weeklong Wesleyan Girls in Science Summer Camp welcomed dozens of middle school-aged girls for a week of learning, exploration, and STEM-centered fun.

From Aug. 5-9 inside Exley Science Center, the 32 campers in grades 4-6 spent the week learning about everything from how to extract DNA from a strawberry, to the parts of the brain, and even how to make (but don’t touch) an ice-cold comet. By Friday, the young scientists were excited to share all they had learned with their friends and families, and did so through a poster presentation and art display.

Girls in Science participants observe a "comet" they created during the camp.

Girls in Science participants observe a “comet” they created during the camp.

This partnership between Wesleyan and Middletown Public Schools gives girls the chance to explore and cultivate their interest in science by conducting fun experiments in real-life labs, discovering scientific concepts, vocabulary and equipment, and learning from female Wesleyan professors and students in the sciences.

This year marked the first time in the program’s history that the camp took place fully under the umbrella of the Jewett Center for Community Partnerships.  Additionally, the Jewett Center partnered with In-Reach, a program coordinated by Melisa Olgun ’20, to bring local high school girls in as program assistants. These young scientists-in-training provided guidance and support for the campers, while also getting to spend time in research labs at Wesleyan.

College of the Environment Supports 32 Student Researchers this Summer

This summer the College of the Environment is funding 32 research opportunities here on campus, from coast to coast, and worldwide, from Connecticut and California to Costa Rica and Ghana.

That’s more than $135K for undergrad research, regardless of major or class year.

Students are studying forest fragmentation in Connecticut; volcanic lake ecosystems in Oregon; Lingzhi mushroom’s influence on Chinese medicine; effects of mercury pollution on Eastern Blacknose Dace snakes; solar cell materials; and much more. 

Personick Selected to Participate in an NSF-Funded Project

Michelle Personick joined the faculty this fall, and is teaching courses in Chemistry of Materials and Nanomaterials and an Integrated Chemistry Lab. (Photo by Olivia Drake)

Michelle Personick

Michelle Personick, assistant professor of chemistry, has been selected by the Leadership Council of the Interactive Online Network of Inorganic Chemists (IONiC) to participate in a National Science Foundation–funded study to develop, test, and refine a flexible, foundation-level inorganic chemistry course.

As a Virtual Inorganic Pedagogical Electronic Resource (VIPEr) Fellow, Personick joins 17 other inorganic chemists from across the country in a community of practice dedicated to improving student learning. The 2018 VIPEr Fellows are the first faculty who have been selected for this groundbreaking project.

The study, titled “Improving Inorganic Chemistry Education,” is being conducted with support from the National Science Foundation’s Improving Undergraduate STEM Education program. The project will use classroom observations, analysis of student work, student surveys, and faculty interviews to study how changes in the classroom affect student learning, interest, and motivation. The project also will investigate how IONiC may encourage the adoption of evidence-based classroom practices.

At Wesleyan, Personick teaches general, inorganic, and materials chemistry. Her research group focuses on developing tailored metal nanomaterials to enable fundamental research toward improved catalysts for resource-efficient chemical synthesis and the clean production of energy.

She received her undergraduate degree from Middlebury College, where she studied platinum anticancer drug analogs, and her PhD from Northwestern University, where she developed syntheses for shaped gold and silver nanoparticles. As a postdoctoral researcher at Harvard University, she studied the catalytic behavior of bimetallic nanoporous alloys.

Read more about Personick in these past News @ Wesleyan articles.

Paper by Robinson, Alumni Published in Behavioural Brain Research

Robinson Lab

A paper coauthored by several members of the Robinson Lab is published in the Oct. 3 issue of Behavioural Brain Research, Volume 371.

The coauthors include Mike Robinson, assistant professor of psychology; graduate student Charlotte Freeland, Callie Clibanoff ’19, Anna Knes ’19, John Cote ’19, and Trinity Russell ’17.

The flashing lights and celebratory sounds that dominate slot-machine gambling are believed to promote engagement and motivation to keep playing. However, these cues are often presented in the absence of reward, and previous research suggests that this reward uncertainty, which degrades their predictive value, also increases their incentive value. In their paper titled “Distinguishing between predictive and incentive value of uncertain gambling-like cues in a Pavlovian autoshaping task,” the researchers used a process called autoshaping to tease apart the impact of reward uncertainty on the predictive and incentive value of a conditioned stimulus using serial cues.

The Robinson Lab’s research program seeks to identify how intense incentive motivations are produced by brain systems, both naturally in extreme cases and less naturally, but still powerfully, in pathological addictions. Their areas of interest include the role of cues in diet-induced obesity, the impact of uncertainty in gambling, and how cues produce craving in drug addiction.

Herbst and Greenwood in The Conversation: The Tell-Tale Clue to How Meteorites Were Made

Wesleyan faculty frequently publish articles based on their scholarship in The Conversation US, a nonprofit news organization with the tagline, “Academic rigor, journalistic flair.” In a new article, John Monroe Van Vleck Professor of Astronomy Bill Herbst and Assistant Professor of Earth and Environmental Sciences James Greenwood write about the model they’ve proposed for how the most common kind of meteorites form—a mystery that has dogged scientists for decades.

The tell-tale clue to how meteorites were made, at the birth of the solar system

April 26, 1803 was an unusual day in the small town of L’Aigle in Normandy, France – it rained rocks.

Over 3,000 of them fell out of the sky. Fortunately, no one was injured. The French Academy of Sciences investigated and proclaimed, based on many eyewitness stories and the unusual look of the rocks, that they had come from space.

The Earth is pummeled with rocks incessantly as it orbits the Sun, adding around 50 tons to our planet’s mass every day. Meteorites, as these rocks are called, are easy to find in deserts and on the ice plains of Antarctica, where they stick out like a sore thumb. They can even land in backyards, treasures hidden among ordinary terrestrial rocks. Amateurs and professionals collect meteorites, and the more interesting ones make it to museums and laboratories around the world for display and study. They are also bought and sold on eBay.

Despite decades of intense study by thousands of scientists, there is no general consensus on how most meteorites formed. As an astronomer and a geologist, we have recently developed a new theory of what happened during the formation of the solar system to create these valuable relics of our past. Since planets form out of collisions of these first rocks, this is an important part of the history of the Earth.

This meteor crater in Arizona was created 50,000 years ago when an iron meteorite struck the Earth. It is about one mile across. W. Herbst, CC BY-SA

This meteor crater in Arizona was created 50,000 years ago when an iron meteorite struck the Earth. It is about one mile across. (Photo by Bill Herbst, CC BY-SA)

The mysterious chondrules

Paper by Kottos, Li ’19 Published in Physical Review Letters

Tsampikos Kottos, professor of physics, and Yaxin Li ’19 are the coauthors of an article titled “Coherent Wave Propagation in Multimode Systems with Correlated Noise” published in the April 18, 2019 issue of Physical Review Letters.

In this study, the coauthors utilize a random matrix theory approach to unveil a physical mechanism that shields wave coherent effects in the presence of disorder (noise).

Joshi ’20 Honored with Research Award to Study DNA Mismatch Repair

Meera Joshi '20

Meera Joshi ’20

Meera Joshi ’20 is the recipient of an American Society for Biochemistry and Molecular Biology (ASBMB) Undergraduate Research Award for her work on the DNA mismatch repair system.

The $1,000 award will support her research titled “Exploring the Dynamics of Msh2-Msh6 Binding to Holliday Junction Through ATPase Activity. Her advisor is Ishita Mukerji, professor of molecular biology and biochemistry.

Joshi’s research focuses on a DNA mismatch repair protein called Msh2-Msh6 that initiates the repair of DNA mismatches after replication in eukaryotes. This is a highly conserved process from bacteria to humans and has implications for human health.

“We are particularly interested in Msh2-Msh6 because of it’s involvement in DNA repair, which when faulty, can lead to cancer,” Joshi explained. Mutations in this protein have been linked to Lynch syndrome, an inherited cancer syndrome, and tumor development.

Joshi is building on the work of a previous Mukerji lab student who characterized the binding affinity of Msh2-Msh6 with Holliday Junctions—a cross-shaped DNA structure with four strands of DNA, mostly seen during genetic recombination. This structure is also an important intermediate in the repair of damaged DNA. As Msh2-Msh6 usually binds to DNA containing one mismatched base pair, the lab is interested in understanding its role when binding to Holliday Junctions.

In order to study how the protein interacts with the Holliday Junction, Joshi will use fluorescent analogs to observe how the protein binds to the junction and if there are any changes in structure because of binding. The award will be used to fund the fluorescent analogs and the DNA needed for the experiments.

“Meera is a strong research student who is dedicated and hard-working,” Mukerji said. “I think she will make a lot of progress on her project this summer and am excited to see the results.”

After graduating from Wesleyan, Joshi hopes to attend graduate school and find a lab that focuses on protein dynamics.

ASBMB’s mission is to advance the science of biochemistry and molecular biology through the publication of scientific and educational journals, the organization of scientific meetings, advocacy for funding of basic research and education, support of science education at all levels, and promoting the diversity of individuals entering the scientific workforce.

Study by Tavernier, Students Published in Sleep Health Journal

oyette Tavernier, assistant professor of psychology, is director of Wesleyan's Sleep and Psychosocial Adjustment Lab housed in Judd Hall. Here, she monitors an individual's nightly sleep patterns. (Photo by Olivia Drake)

Royette Tavernier, assistant professor of psychology, is director of Wesleyan’s Sleep and Psychosocial Adjustment Lab.

College-aged individuals are at an increased risk for mental health issues, as well as poor sleep. There is a rich body of research on the negative consequences of poor sleep for cognitive, physical, and mental functioning. Furthermore, several studies provide support for the importance of three basic psychological needs (autonomy, competence, and relatedness) for optimal mental well-being. Less well understood, however, is the issue of “directionality” between basic psychological needs and sleep as students transition across semesters.

“In other words, it is not clear whether an individual’s perceived fulfillment of these basic psychological needs predicts improvements in sleep later on; or whether sleep patterns at baseline might subsequently lead to improvements in these psychological needs over time,” said Royette Tavernier, assistant professor of psychology. “This issue of directionality (the ‘chicken and the egg’ phenomenon) is critical for understanding which factors interventions should target to promote optimal sleep and psychological well-being.”

Tamare Adrien '19 and Grant Hill '20 shared their sleep studies at the Department of Psychology’s Research Poster Presentation on April 25.

Tamare Adrien ’19 and Grant Hill ’20 shared their sleep studies at the Department of Psychology’s Research Poster Presentation on April 25.

In a recently published paper titled “Be well, sleep well: An examination of directionality between basic psychological needs and subjective sleep among emerging adults at university,” coauthors Tavernier, Grant Hill ’20, and Tamare Adrien ’19 examined the relationship between basic psychological needs and sleep quality. Their findings appear in the April issue of the journal Sleep Health.

They find that when University participants perceived that their psychological needs for autonomy, competence, and relatedness were met, they reported improvements in sleep duration (slept for longer hours) and sleep quality (reported fewer sleep problems) one semester later. Additionally, they found a significant ‘bidirectional effect’ between perceived fulfillment of the three basic psychological needs and lower daytime dysfunction (i.e., perceived enthusiasm to function during the day), indicating that both these variables mutually predict each other over time.

The authors conclude that while many sleep interventions focus on environmental aspects of sleep, their study highlights the importance of nurturing college students’ psychological needs as a possible approach to improve sleep among this vulnerable sample.

Tavernier is a developmental psychologist and is director of Wesleyan’s SPA Lab.

Natural Sciences and Mathematics Division Hosts Celebration of Science Theses

On April 26, honors and graduate students in the Natural Sciences and Mathematics Division presented posters at the Celebration of Science Theses.

On April 26, honors and graduate students in the Natural Sciences and Mathematics Division presented posters at the Celebration of Science Theses.

Han Yang Tay presented a poster titled "Rich Club and Diverse Club in Structural and Functional Neuroimaging Data." His advisor is Psyche Loui

Han Yang Tay ’19 speaks to Barbara Juhasz, associate professor of psychology, about his study titled “Rich Club and Diverse Club in Structural and Functional Neuroimaging Data.” His advisor is Psyche Loui, assistant professor of psychology.