Tag Archive for Chemistry

Scientific Images of Nanoparticles, Colliding Stars, Learned Words Win Annual Contest

We had 13 submissions this year.

Thirteen students, majoring in chemistry, physics, astronomy, molecular biology and biochemistry, biology, neuroscience and behavior, psychology, and quantitative analysis submitted images for the 2021 Scientific Imaging Contest.

At first glance, a viewer sees a single image of pink-tinted cubes, resembling a bacteria culture from high school biology.

But upon closer examination, the viewer begins to see a series of other shapes—triangles to hexahedrons to tetahexahedraons (cubes with four-sided pyramids on each face).

“If you stare at this image for a while, you can see that it’s actually a series of five images in the top row, and five images on the bottom row, and each of these images show us nanoparticles that are made of gold and copper,” said Brian Northrop, professor of chemistry. “It’s intriguing, captivating, and visually very interesting.”

The image, which depicts bimetallic gold-copper (Au-Cu) nanoparticles synthesized with varying concentrations and amounts of sodium iodide, was created by Jessica Luu ’24 using a scanning electron microscope. It also was the first place winner in Wesleyan’s 2021 Scientific Imaging Contest.

Jessica Luu

Jessica Luu ’24 took first place with a series of 10 images of bimetallic gold-copper (Au-Cu) nanoparticles synthesized with varying concentrations and amounts of sodium iodide. They were imaged using a scanning electron microscope (SEM).

The annual contest, spearheaded by Wesleyan’s College of Integrative Sciences, encourages students to submit images and descriptions of the research that they’ve been conducting over the summer.

Faculty Collaborate on New, Patent-Pending, Hypersensitive Accelerometer

Tsampikos Kottos, Lauren B. Dachs Professor of Science and Society, professor of physics; Rodion Kononchuk, postdoctoral physics research associate; and Joseph Knee, Beach Professor of Chemistry

Tsampikos Kottos, Lauren B. Dachs Professor of Science and Society, professor of physics; Rodion Kononchuk, postdoctoral physics research associate; and Joseph Knee, Beach Professor of Chemistry, are developing a hypersensitive sensor at Wesleyan.

When launching spacecrafts and missiles, small navigational mistakes could lead to catastrophic results. A satellite could spin completely out of orbit, a missile could mistakenly strike a civilian territory, or a spaceship could end up at another planet altogether.

Three Wesleyan researchers are collaborating on the development of a novel sensor that would benefit navigation and several other applications.

The new, hypersensitive acceleration sensor is based on a principle borrowed from nuclear physics and has been developed at Wesleyan. It provides enhanced sensitivity and precision compared to conventional sensors.

“Our underlying concept can be applied in a variety of sensing applications ranging from avionics and earthquake monitoring to bio-sensing,” said study co-author Rodion Kononchuk, postdoctoral physics research associate in Wesleyan’s Wave Transport in Complex Systems Laboratory. “We believe that our results will attract a broad interest from research and engineering communities across a wide range of disciplines, which could result in a realization of next-generation sensors.”

In a June 2021 Science Advances article titled “Enhanced Avionic Sensing Based on Wigner’s Cusp Anomalies,” Kononchuk, along with Tsampikos Kottos, Lauren B. Dachs Professor of Science and Society, professor of physics; Joseph Knee, Beach Professor of Chemistry; and Joshua Feinberg, professor of physics at the University of Haifa in Israel, shared their study’s results.

The Wesleyan team has demonstrated a whopping 60-fold improved performance in acceleration measurements compared to conventional accelerometers (i.e. sensing devices that measure variations in the acceleration). Wesleyan has already supported a provisional patent application for this study.

Kottos, who spearheads the Physics Department’s Wave Transport in Complex Systems Laboratory, says a “good sensor” is characterized by two elements: its high sensitivity to small “perturbations” and its dynamical range. The latter is the ratio of the maximum to the minimum perturbation that a sensor can detect. And the larger the dynamic range, the better it is.

“Think of a spacecraft or missile. When it takes off, it develops high accelerations, but in the voyage, it needs to detect small accelerations in order to correct its trajectory,” Kottos said. “We believe that our sensor has the ability to measure such a large range of accelerations. Moreover, it is simple to implement and does not suffer from excessive noise that can degrade the quality of the measurements—as opposed to some recent proposals of hypersensitive sensing.”

Although the project is heavily physics-based, Kottos and Kononchuk knew they needed a chemist to help turn their theories into a reality. As it turned out, Knee—who is an expert on optical sensing—had laboratory experience that was applicable to the current project.

“It was wonderful to be brought into such an exciting project,” Knee said. “My research area is in laser spectroscopy which requires significant expertise and experimental capabilities in optical physics. Fortunately, my lab had some key capabilities which helped us put together an experimental prototype that ultimately was used to validate the theoretical constructs.”

“Joe’s experimental expertise in the chemistry framework was crucial for building the experimental platform,” Kottos said. “Our initial discussions helped us to better understand what can or cannot be done and allowed us to successfully design the experiment with a limited budget.”

Kottos began research for the new hypersensitive avionic sensor design in 2018 after receiving a grant from the U.S. Department of Defense. The guiding principles were to maximize the sensitivity of the sensor without compromising its dynamical range [i.e. the ratio between the largest and smallest perturbation that a sensor can measure] while making it as cheap and simple to make, as possible.

The current sensor design is approximately 4 inches long, but the size could be reduced depending on the application. Smartphone sensors, for example, measure about 1/4 of an inch, but they are far less sensitive than the design created at Wesleyan. Wesleyan undergraduate Jimmy Clifford ’23 is currently working on simulations to come up with a miniaturized design of this concept.

“Once we have it, either we will have to partner with a fabricator or we will have to off-shore the design and test it at Wesleyan,” Kottos said. “We hope to take this concept to production and hopefully to the marketplace!”

Read more:
The Why Axis: Cutting-Edge Science at Wesleyan (Wesleyan University Magazine)

Kottos Awarded Simons Collaborative Grant to Advance Wave Transport Research

Kottos Awarded $2.8M DARPA Grant for High-Level Photonic Research

Kottos Awarded Engineering Grant from the National Science Foundation

Taylor Co-Authors 3 Articles, Writes Book Chapter on Lignin Enzymology

Erika Taylor

Erika Taylor

Erika Taylor, associate professor of chemistry, recently co-authored three papers and a book chapter related to (1) biomass to biofuel production and (2) development of new therapeutics to treat Gram-negative bacterial infections.

Taylor’s work investigates problems at the biological chemistry interface and seeks to find applications of her work to the fields of medicine and sustainable energy.

Her chapter called “Lignin Enzymology – Recent Efforts to Understand Lignin Monomer Catabolism” in the book Comprehensive Natural Products III: Chemistry and Biology, and her paper “Identifying Metabolic Pathway Intermediates that Modulate Enzyme Activity: A Kinetic Analysis of the DesB Dioxygenase from Sphingobium sp. strain SYK-6,” published in Process Biochemistry in January 2021, both help illustrate the mechanisms for breaking down Lignin, an important biopolymer that provides the structural integrity of terrestrial plants. The DesB paper is coauthored with alumnus Stacy Uchendu ’17 and other members of her lab. Her work is aimed toward helping understand ways to improve the efficiency of biofuel and fine chemical production.

The remaining papers describe efforts to understand the machine-like motions of the protein Heptosytransferase I and efforts to design inhibitors against them to treat bacterial infections:

A General Strategy to Synthesize ADP-7-azido-heptose and ADP-azido-mannoses and their Heptosyltransferase Binding Properties,” published in Organic Letters in February 2021.

Her paper, “Conserved Conformational Hierarchy Across Functionally Divergent Glycosyltransferases of the GT-B Structural Superfamily as Determined from Microsecond Molecular Dynamics,” published in the International Journal of Molecular Sciences in April 2021.

This summer, Taylor is overseeing the McNair research program with Ronnie Hendrix, and in the fall, she will be teaching a new First Year Seminar titled Chemistry in Your Life.

Cote PhD ’18, Hecht MA ’19, Taylor Co-Author New Paper in Biochemistry

Joy Cote PhD ’18, Cody Hecht ’18, MA’19, and Erika Taylor, associate professor of chemistry, are the co-authors of a study that explores how opposite charges on our substrate and enzyme cause a protein to change shape when the substrate binds.

The study, titled “Opposites Attract: Escherichia coli Heptosyltransferase I Conformational Changes Induced by Interactions between the Substrate and Positively Charged Residues,” appears in the February 2020 issue of Biochemistry.

“If you can imagine how the opposite charges of magnets are attracted toward each other, then you understand the results of this paper,” Taylor explained. “The enzyme uses positively-charged amino acids to attract its substrate, which has many negatively charged regions. The attraction of the enzyme to the substrate even causes the shape of the protein to change, closing in on the substrate, like the way the fingers of your hand might bend to grasp a ball.”

The researchers describe how they introduced mutations into the amino acid sequence of this protein, and observated how these mutated residues impact the reactivity and protein behavior both in laboratory experiments and in computational studies.

“The amazing thing about these interactions is that they allow the protein to be stable at 203 degrees F, which is almost the boiling point of water, when normally proteins from Escherichia coli are only stable near human body temperatures,” Taylor said.

Although it isn’t clear exactly how the protein becomes so stable, the researchers are intrigued by how the interactions of these charged groups play a major role in that stabilization process.

Taylor Named a “Top 35 Woman in Higher Education” by Diverse

Erika Taylor

Erika Taylor

Erika Taylor, associate professor of chemistry, is honored for being among the “Top 35 Women in Higher Education” in the March 20 issue of Diverse.

Taylor joined the Wesleyan faculty in 2007 and teaches courses in the areas of organic chemistry, biochemistry, environmental chemistry, and bio-medicinal chemistry, among others.

She’s also associate professor, environmental studies, and associate professor, integrative sciences, and takes a multidisciplinary approach to investigating problems at the biological chemistry interface.

Diverse acknowledged Taylor for “striv(ing) to find ways to exploit enzymes found in nature to perform reactions that can help advance the fields of chemistry and medicine.” Her research group has included over 75 students to date, spanning high schoolers to PhD students, with women and other underrepresented students comprising more than three-quarters of her lab members.

Molecular Biophysics Program Hosts 20th Annual Retreat

MBB

Three Wesleyan faculty, one guest, and one alumnus delivered talks during the 20th Annual Molecular Biophysics Retreat on Sept. 26. The speakers included David Beveridge, Joshua Boger University Professor of the Sciences and Mathematics, Emeritus; Lila Gierasch, Distinguished Professor of Biochemistry and Molecular Biology and Chemistry at the University of Massachusetts, Amherst; Erika Taylor, associate professor of chemistry; Michael LeVine ’11 of D.E. Shaw Research; and Laverne Melón, assistant professor of biology.

On Sept. 26, the Molecular Biophysics Program hosted its 20th Annual Molecular Biophysics Retreat at Wadsworth Mansion in Middletown. Several Wesleyan faculty, students, and guests attended the all-day event, which included five talks, two poster sessions, and a reception.

Lila Gierasch, Distinguished Professor of Biochemistry and Molecular Biology and Chemistry at the University of Massachusetts, Amherst, delivered the keynote address, titled “Hsp70s: Allosteric Machines that Perform a Multitude of Cellular Functions.” Gierasch, a leader in the field of protein folding, is a newly elected member of the National Academy of Sciences. Her work focuses particularly on folding in the cell and understanding the action of folding helper proteins, known as chaperones. Her career-long contributions were recently recognized by the American Peptide Society with a lifetime achievement honor, the Merrifield Award. She is also a recipient of the American Chemical Society’s Ralph F. Hirschmann Award in Peptide Chemistry, an elected member of the American Academy of Arts and Sciences, and is currently editor-in-chief of the premier biochemical publication, the Journal of Biological Chemistry.

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.

Members of the Class of 2019 Inducted into Phi Beta Kappa

PBK

On May 25, members of the Class of 2019 were inducted into Wesleyan’s Gamma Chapter of Phi Beta Kappa Society, the oldest national scholastic honor society. The Wesleyan Gamma Chapter was organized in 1845 and is the ninth-oldest chapter in the country.

To be elected, a student must first have been nominated by the department of his or her major. The student also must have demonstrated curricular breadth by having met the General Education Expectations and must have achieved a GPA of 93 and above.

Phi Beta Kappa is the oldest surviving Greek letter society in America, founded in December 1776 by five students who attended the College of William and Mary in Williamsburg, Virginia. The emblem contains the three Greek letters “Phi-Beta-Kappa,” which are the initials of the Greek motto, Philosophia Biou Kybernetes. This essentially means “the love of wisdom is the guide of life.”

The spring 2019 inductees are:

Caroline Adams
Yulia Alexandr
Erin Angell
William Bellamy
Cara Bendich
Zachary Bennett
Chiara Bercu
Sophie Brett-Chin
Nicholas Byers
David Cabanero
Talia Cohen
John Cote 

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.

Fowler, Northrop, Siry Receive Binswanger Prizes for Excellence in Teaching

2019 Binswanger winners

Wesleyan faculty (from left) Joseph Siry, Brian Northrop, and Erika Franklin Fowler join President Michael Roth before the 187th Commencement ceremony, May 26. During the ceremony, the three professors were honored with Binswanger Prizes for Excellence in Teaching. (Photo by Olivia Drake)

Every year at Commencement, Wesleyan recognizes three outstanding teachers with Binswanger Prizes for Excellence in Teaching. These prizes, made possible by gifts from the family of the late Frank G. Binswanger Sr., Hon. ’85, underscore Wesleyan’s commitment to its scholar-teachers, who are responsible for the University’s distinctive approach to liberal arts education.

Recommendations are solicited from alumni of the last 10 graduating classes, as well as current juniors, seniors, and graduate students. Recipients are chosen by a selection committee of faculty and members of the Alumni Association Executive Committee.

This year, during the 187th Commencement ceremony, Wesleyan honored the following faculty members for their excellence in teaching:

Erika Franklin Fowler
Erika Franklin Fowler, associate professor of government and director of the Wesleyan Media Project, has taught at Wesleyan since 2009. She has a BA in political science and mathematics from St. Olaf College, and an MA and PhD in political science from the University of Wisconsin–Madison. She served as a Robert Wood Johnson Scholar in Health Policy Research at the University of Michigan School of Public Health from 2007 to 2009.