Simons Society of Fellows: 2015 Junior Fellows

Junior Fellows by year

The Simons Foundation is pleased to announce the Junior Fellows appointed in 2015.

Tobias Bartsch

Tobias Bartsch is a postdoctoral researcher in Professor A. J. Hudspeth’s Laboratory of Sensory Neuroscience at the Rockefeller University. He attended college at the University of Würzburg in Germany and received his Ph.D. in physics from the University of Texas at Austin.

During his time in graduate school, Bartsch worked with Professor E. L. Florin on the development of a novel three-dimensional scanning-probe microscope capable of imaging soft matter with a nanometer spatial resolution at a megahertz bandwidth. Using the microscope, Bartsch studied the interaction of single ligand-receptor pairs, the cooperativity of molecular motors and the nanoscopic mechanics of biopolymer networks. His graduate research was supported by a full scholarship from the German Academic Exchange Service (DAAD) and a Lawrence Biedenharn Fellowship; his dissertation was recognized by the University of Texas at Austin as an “outstanding dissertation in physics.”

His current research focuses on the mechanical properties of soft biological matter under low, physiologically relevant forces close to the thermal limit. In particular, using a high-precision apparatus, he is elucidating the elasticity of the molecular spring that underlies auditory sensation and is investigating how different disease-associated mutations affect the properties of this spring.

Michal Breker

Michal Breker is a postdoctoral fellow in the laboratory of Professor Fred Cross at the Rockefeller University. She received her master’s degree in immunology in 2008 and completed her Ph.D. in 2013 at the Department of Molecular Genetics, both at the Weizmann Institute of Science in Israel. Her doctoral work focused on stress responses and proteome dynamics in baker’s yeast. Prior to coming to the Weizmann Institute, Breker received her B.Sc. in neuroscience at Tel Aviv University.

In her postdoctoral studies, Breker is interested in studying the genetic networks that underlie growth and division in plants. She employs the single-celled Chlamydomonas, a microbial representative of the plant superkingdom, to develop novel high-throughput genome-wide approaches, applied for the first time in plants, to better understand a key model organism for biofuel production and food supply.

Breker has earned numerous awards, including the L’Oreal-UNESCO For Women in Science Award for Israel, the Israel National Postdoctoral Award for Advancing Women in Science from the Weizmann Institute, and student grant awards from the Azrieli Institute for Systems Biology and The Khan Family Research Center for Systems Biology program.

Jennifer Bussell

Jennifer Bussell is a postdoctoral researcher in the laboratory of Dr. Richard Axel in the Department of Neuroscience at Columbia University. She received her Ph.D. from the Rockefeller University and her A.B. from the University of Chicago. Prior to entering graduate school, Dr. Bussell worked for three years as a management consultant, conducting market research for biotechnology companies.

Dr. Bussell wants to understand how neural circuits encode biological drives such as sex, hunger and curiosity. Her graduate work in the laboratory of Dr. Leslie Vosshall focused on the neural circuitry of sexual behavior. Using the more simple brain of the fly Drosophila melanogaster as a model system, she studied the social interactions flies use in deciding whether to mate and discovered a group of neurons that controls female mating receptivity.

Jairo A. Diaz

Jairo A. Diaz is a postdoctoral research associate at the Center for Soft Matter Research at New York University. There, he investigates the dynamics and self-assembly of soft matter at the mesoscopic scale with Professor David J. Pine. Diaz received his B.S. from the National University of Colombia, Bogota, and his Ph.D. from Purdue University.

His doctoral research was primarily focused on controlling the self-assembly of chiral nanocrystals to finely tune thermal and optical properties of thin films used for organic electronics. His approach of coupling contrast-enhanced microscopy with digital image correlation contributed to the measurement of thermal strains in soft materials. His research has deserved previous recognitions, such as the Purdue Bilsland Dissertation Fellowship and Materials Research Society Graduate Student Award.

Benjamin Harrop-Griffiths

Benjamin Harrop-Griffiths is a postdoctoral researcher in mathematics at the Courant Institute of Mathematical Sciences at New York University. He completed his Ph.D. at the University of California, Berkeley under the supervision of Daniel Tataru. He previously received an MMath in mathematics from Magdalen College, University of Oxford.

His research focuses on the local and global dynamics of nonlinear dispersive partial differential equations. These equations arise in numerous physical situations, such as water waves, plasma physics and nonlinear optics. His doctoral work has included low-regularity local well-posedness results for certain generalizations of the KdV equation, results on the modified asymptotic behavior of the mKdV equation and, in collaboration with Mihaela Ifrim and Daniel Tataru, results on the global behavior of solutions to the KP-I equation.

Kohei Inayoshi

Kohei Inayoshi received his bachelor’s and master’s degrees in physics from Kyoto University, Japan. He obtained his Ph.D. in physics from Kyoto University in 2014 and currently works at Columbia University as a JSPS research fellow.

His research focuses on supermassive black holes (SMBHs), which are extremely huge objects at the center of most galaxies possessing masses between millions to tens of billions of times that of the Sun. Such SMBHs are observed at the early epoch of the Universe, and the fact that SMBHs form and grow quickly gives a strong constraint on their formation process. One promising solution to this puzzle is the formation of massive seed black holes through the gravitational collapse of supermassive stars.

He studied the necessary conditions for supermassive star formation. Using hydrodynamical simulations, he showed for the first time that a primordial gas cloud undergoes runaway collapse without a major episode of fragmentation and forms a supermassive star if certain necessary conditions are satisfied. The results will be useful to understand the grand picture of SMBH evolution across the cosmic time.

Rafael Maia

Rafael Maia is a postdoctoral fellow in the Department of Ecology, Evolution and Environmental Biology at Columbia University, working in the laboratory of Dr. Dustin Rubenstein. Dr. Maia received his master’s in ecology from the Universidade de Brasília (Brazil) in 2008 and his Ph.D. in integrated bioscience from the University of Akron in 2014. Prior to joining Columbia, he was a postdoctoral fellow with Dr. Luke Harmon in the Department of Biological Sciences at the University of Idaho.

Dr. Maia’s research integrates multiple fields of biology, physics and materials science to understand the evolution and diversification of ornamental traits evolving under sexual and social selection. His research has focused on iridescent colors found in bird feathers, exploring how the optics of these nanostructurally organized tissues interact with light to produce colors, how these arrangements form from tissue interactions during feather development and the consequences of this architecture for the evolutionary trajectories of their plumage colors. His research has shown how the evolution of these colors, which are important visual signals in animal social interactions, can be evolutionary constrained due to these underlying templates and how evolutionary innovations can promote the rapid evolution of novel and unique signals. He also develops open-source software for color analyses and comparative macroevolutionary methods, which have been largely adopted by researchers in these fields.

Aditi Sheshadri

Aditi Sheshadri is a postdoctoral research scientist in the Department of Applied Physics and Applied Mathematics at Columbia University, hosted by Professor Lorenzo M. Polvani. She has a bachelor’s degree in mechanical engineering from the R. V. College of Engineering in Bangalore, India, and a master’s degree in aeronautics and astronautics from the Massachusetts Institute of Technology in Cambridge, Massachusetts.

She is expected to complete her Ph.D. in atmospheric science at MIT in June 2015. Her doctoral thesis advisor is Professor R. Alan Plumb. Sheshadri is interested in atmospheric dynamics and climate in general. Her doctoral work has focused on the dynamics and variability of the stratospheric polar vortices in both hemispheres, and the impact of their variability on surface weather and climate. Her recent work has been aimed at understanding the dramatic collapse of the stratospheric westerlies that occur in the wintertime northern hemisphere and at the end of winter in both hemispheres. These events have implications for surface climate, since they result in persistent perturbations to surface weather that can last for up to two months after the event. At Columbia, she will continue to study the circulation of the stratosphere and troposphere, eddy-mean flow feedbacks, and the role of the stratosphere in setting the state of climates of the past.