Tag Archive for graduate students

Karimi Shares Enzyme Research during Graduate Speaker Series

graduate student

Neuroscience and biology BA/MA graduate student Helen Karimi presented a Graduate Speaker Series talk on Nov. 1.

On Nov. 1, neuroscience and biology BA/MA graduate student Helen Karimi presented a Graduate Speaker Series talk titled “All good things come in pairs: Uncovering the activity of BcnI through co-localization microscopy.”

Karimi’s talk focused on restriction endonucleases (REases), a large family of enzymes that make sequence-specific cuts in DNA. As her abstract details, type IIP REases usually cleave sequences as homodimers. However, BcnI, an enzyme belonging to this subtype, acts in a different way. Karimi’s work aims to observe the fine details of BcnI’s cleavage mechanism by using Total Internal Reflection Fluorescence (TIRF) microscopy, an imaging technique in which only molecules within a few hundred nanometers of a glass surface are illuminated.

Paper on Bacteria Adhesion Named “Editor’s Pick” by Journal of Biological Chemistry

Rich Olson

Rich Olson

Katherine Kaus PhD '18

Katherine Kaus

A paper written by Associate Professor of Molecular Biology and Biochemistry Rich Olson and his former students was designated as an “Editor’s Pick” by the Journal of Biological Chemistry. Only 2% of the approximately 6,600 papers published each year in the journal receive this designation.

Titled “The 1.9 Å crystal structure of the extracellular matrix protein Bap1 from Vibrio cholerae provides insights into bacterial biofilm adhesion,” the paper, published on Oct. 4, explores how bacteria “glues” itself to surfaces in the environment. The co-authors include Alison Biester ’19, Ethan Chupp ’18, Jianyi Lu ’17, Charlie Visudharomn ’17 and Katherine Kaus PhD ’18. Kaus, who is first author on the paper, is featured in a special profile on the JBC website.

Bacteria commonly form structures called biofilms, which are communities of living cells encapsulated by a three-dimensional matrix of secreted proteins, nucleic acids, and carbohydrates. Biofilms are a defense mechanism against environmental challenges and play a role in many pathogenic diseases.

Wesleyan in the News

NewsIn 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. The Nation: “Edward Snowden Deserves to Be Tried by a Jury of His Peers, Just Like Everyone Else”

In this op-ed, Associate Professor of Government Sonali Chakravarti argues against the Justice Department’s decision to deny Edward Snowden’s request for a jury trial. She contends that in Snowden’s case, in which he is accused of leaking classified information from the National Security Administration in 2013, a jury trial “is not only a viable alternative to a hearing before a judge; rather, given the nature of the charges—where the defendant has supposedly acted to protect the people from the very state that would charge him with a crime—jury deliberation is the proper forum for discussion of appropriate punishment and is the bulwark against the potential misconduct of the state.”

2. Transitions Online: “Stuck in the Middle”

Peter Rutland, the Colin and Nancy Campbell Professor in Global Issues and Democratic Thought, professor of government, and Dmytro Babachanakh ’20 explore the history of U.S. involvement in Ukraine, and call upon U.S. leaders of both parties to stop “treating lesser powers as political instruments.”

3. Tulsa World: “Save the Little Grouse on the Prairie”

Alex Harold ’20 is the author of this op-ed that calls for the lesser prairie chicken to be placed on the endangered species list to get the protections it desperately needs, as over 90 percent of its habitat has been degraded or destroyed. While many haven’t heard of this bird, Harold explains that it is an “indicator species” that “reflect(s) the health of the entire prairie ecosystem.” Harold wrote the op-ed as an assignment in E&ES 399, Calderwood Seminar in Environmental Science Journalism, taught by Professor of Earth and Environmental Sciences Suzanne O’Connell, this semester. The Calderwood Seminars are offered in a variety of disciplines to teach students how to effectively communicate academic knowledge to the public. Read more here.

Wesleyan Welcomes 60 New Graduate Students

graduate students

Wesleyan welcomes 162 graduate students to campus this fall, of which 60 are new.

Of these:

  • 23 new students are enrolled in the BA/MA programs in biology, chemistry, computer science, molecular biology and biochemistry, neuroscience and behavior, physics, and psychology.
  • 13 new students are enrolled in a two-year MA program in astronomy, earth and environmental sciences, and music.

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.

Varekamp Presents Papers at Volcanic Lakes Meeting in New Zealand, Receives Award

Johan (Joop) Varekamp

Joop Varekamp

Johan (Joop) Varekamp, the Harold T. Stearns Professor of Earth Science, presented three papers during the Commission on Volcanic Lakes (CVL) program held March 18-20 in Taupo, New Zealand. The papers were coauthored by Wesleyan students, graduate students, recent alumni, and faculty.

The CVL is a scientific, nonprofit organization of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI), connecting researchers that seek to understand how volcanic lakes relate to volcanic activity and their hazards.

Varekamp, who also is the Smith Curator of Mineralogy and Petrology of the Joe Webb Peoples Museum of Natural History and professor of earth and environmental studies, is a former leader of the CVL organization. In addition to delivering a keynote address, Varekamp was named the recipient of the 2019 IAVCEI Kusakabe Award.

Case, Hingorani Coauthor Study on Repair of DNA Damaged by Sunlight

Brandon Case

Molecular biology and biochemistry graduate student Brandon Case and Professor Manju Hingorani are coauthors of a study published in Nucleic Acids Research in March 2019.

The paper, titled “The ATPase mechanism of UvrA2 reveals the distinct roles of proximal and distal ATPase sites in nucleotide excision repair,” reports new findings on how the UvrA2 protein uses its ATPase activity to probe DNA for damage lesions, such as those caused by UV radiation, and initiate nucleotide excision repair (NER). This DNA repair process corrects tens of thousands of lesions introduced daily into the human genome by UV rays and chemical agents.

Naegele Lab Releases New Study on Temporal Lobe Epilepsy

Jyoti Gupta, who earned her PhD in biology in 2018, is pictured presenting her dissertation defense at Wesleyan. Gupta is the lead author on a recently published study that investigates abnormal neuron growth in mice that have temporal lobe epilepsy.

Adult neurogenesis, a process whereby new neurons are added to the brain, is thought to be confined in mammals to just a few regions, including the hippocampus, a structure important for learning. Whether this process occurs in the adult human brain is controversial, but in most other mammals that have been studied, adult neurogenesis in the hippocampus appears to be essential for forming memories.

Producing new neurons in the adult hippocampus is regulated by the environment, mood, exercise, diet, and disease. In some forms of epilepsy, the production of new cells in the hippocampus, called granule cells, becomes highly abnormal and the altered neurogenesis is thought to increase over-excitation and exacerbate seizures.

Students, Faculty, Alumni Present Research at 50th Annual Planetary Science Conference

Jeremy Brossier presented a talk titled "Radiophysical Behaviors of Venus’ Plateaus and Volcanic Rises: Updated Assessment." He also presented a poster titled "Complex Radar Emissivity Variations at Some Large Venusian Volcanoes."

At left, earth and environmental sciences postdoctoral research associate Jeremy Brossier presented a poster titled “Complex Radar Emissivity Variations at Some Large Venusian Volcanoes” during the Lunar and Planetary Science Conference in Texas.

Several Wesleyan students, faculty, and alumni attended the 50th Lunar and Planetary Science Conference (LPSC) March 18-22 in The Woodlands, Texas. Members of the Wesleyan Planetary Sciences Group presented their research on a range of planetary bodies.

This annual conference brings together international specialists in petrology, geochemistry, geophysics, geology, and astronomy to present the latest results of research in planetary science.

Earth and environmental studies major Emmy Hughes ’20 presented a poster titled “Observations of Transverse Aeolian Ridges in Digital Terrain Models” during a session on “Planetary Aeolian Processes.”

Earth and environmental science graduate student Reid Perkins MA ’19 presented a talk titled “A Reassessment of Venus’ Tessera Crater Population and Implications for Tessera Deformation” and a poster titled “Volumes and Potential Origins of Crater Dark Floor Deposits on Venus.”

Grad Student Kemble Discusses Heavy Metal Feminism

Katrice Kemble, a graduate student in ethnomusicology, presented a talk on "Daughters of Darkness: Performing Heavy Metal Feminism" on Feb. 27 during the Graduate Speakers Series.

Katrice Kemble, a graduate student in ethnomusicology, presented a talk on “Daughters of Darkness: Performing Heavy Metal Feminism” on Feb. 27 during the Graduate Speakers Series.

Kemble's research explores the oft-overlooked roles of women in the mainstream heavy music industry by following the bands Halestorm, In This Moment, and New Years Day on a female-fronted tour of the United States. Their performance of heavy metal feminism raises important questions about gender representation in popular culture, feminism and sexualization, genre expectations, and beyond.

Kemble’s research explores the oft-overlooked roles of women in the mainstream heavy music industry by following the bands Halestorm, In This Moment, and New Years Day on a female-fronted tour of the United States. Their performance of heavy metal feminism raises important questions about gender representation in popular culture, feminism and sexualization, genre expectations, and beyond. (Photos by Preksha Sreewastav ’21)

Klusmeyer Receives a Chambliss Award for Astronomy Research

After a star forms, a dusty ring of space debris may begin orbiting around a star. These circumstellar disks are composed of asteroids or collision fragments, cosmic dust grains, and gasses.

Astronomy graduate student Jessica Klusmeyer is interested in understanding the molecular composition of the debris disk gas. “It has important implications not only for our knowledge of debris disks but also for planet formation,” she said.

Klusmeyer joined more than 25 Wesleyan affiliates and shared her research during the 233rd American Astronomical Society Meeting Jan. 6-10 in Seattle, Wash. The American Astronomical Society (AAS) awarded Klusmeyer a Chambliss medal for her poster presentation titled, “A Deep Search for Five Molecules in the Debris Disk around 49 Ceti.”

The Astronomy Achievement Student Awards recognize exemplary research by undergraduate and graduate students who present at one of the poster sessions at the meetings of the AAS. Awardees are honored with a Chambliss medal or a certificate.

Klusmeyer competed for the Chambliss award against hundreds of graduate and PhD students from research universities around the country.

A second-year masters student, Klusmeyer is working on the project with her advisor, Meredith Hughes, assistant professor of astronomy and assistant professor, integrative sciences.

“Professor Hughes has a very active and supportive research group that covers a wide variety of circumstellar disks and planet formation topics,” Klusmeyer said. “She works in radio wavelengths of light and the group often utilizes data from the world-class Atacama Large Millimeter/submillimeter Array (ALMA) telescope.”

Klusmeyer joined Hughes’s group during her first year of graduate school and is working on unlocking the molecular composition of a nearby debris disk surrounding 49 Ceti, a star located in the constellation of Cetus. Cetus, which is named after a Greek sea monster, resembles the shape of a whale and can be viewed from campus (or as far away as Chile!).

Scientists once thought that debris disks would lose their gas composition after planet formation, however, more than 20 debris disks containing molecular carbon monoxide gas have already been detected by astronomers.

“Our project wants to understand the nature of this gas,” Klusmeyer explained. “Is it leftover material from when the star formed, or is it constantly being produced in collisions from exocomets or other small bodies orbiting around 49 Ceti?”

If a debris disk has gas, “it may provide a longer period of time for gas giant planet formation or we could detect other molecules commonly found in comets and have the first glance at the molecular composition of comets around other stars,” she said.

Girish Duvvuri ’17 received a Chambliss medal in 2018. Read more.

Students, Faculty, Alumni Attend American Astronomical Society Meeting

Mark Popinchalk ’13

Roy Kilgard and Mark Popinchalk ’13.

More than 25 Wesleyan affiliates attended the 233rd American Astronomical Society Meeting Jan. 6-10 in Seattle, Wash. All current Wesleyan students who attended presented posters of their research.

Campus attendees included: Bill Herbst, the John Monroe Van Vleck Professor of Astronomy and professor, integrative sciences; Roy Kilgard, associate professor of the practice in astronomy and associate professor of the practice, integrative sciences; Michael Henderson ’19; Allison Quintana ’19; graduate student Jessica Klusmeyer; graduate student Ismael Mireles; and graduate student Anthony Santini ’18.

Alumni included Hannah Fritze ’18, Aylin Garcia Soto ’18, Prajwal Niraula MA ’18, Amy Steele MA ’14, Nicole Arulanantham MA ’15, Mark Popinchalk ’13, Marshall Johnson ’11, Anna Williams ’09, Ken Rumstay MA ’77, Taft Armandroff ’82, Phil Choi ’95, Anil Seth ’98, Evan Tingle ’08, MA ’09, Diana Windemuth MA ’13, Trevor Dorn-Wallenstein ’15, Clara Moskowitz ’05, Emily Leiner ’10.

Diana Windemuth MA ’13 and Aylin Garcia Soto ’18

Diana Windemuth MA ’13 and Aylin Garcia Soto ’18.

Former graduate student Colin Littlefield, and former post-doctoral researchers Vicki Sarajedini and John Cannon also attended.

In addition, five college students who participated in the Keck Northeast Astronomy Consortium’s (KNAC) summer Research Experiences for Undergraduate (REU) program at Wesleyan attended the meeting. Karina Cooper, Sadie Coffin, Aleezah Ali, Katie Chapman, and Diego Garcia worked at Wesleyan’s observatory last summer and were under the direction of Wesleyan faculty and students.

View additional photos of the meeting in this Van Vleck Observatory blog.