Congratulations to Grace Han, Assistant Professor of Chemistry and Landsman Career Development Chair in the Sciences. She has been awarded funds from the Department of Defense to purchase a bench-top X-ray diffraction instrument. This award is part of the DoD’s Defense University Research Instrumentation Program (DURIP) that will provide $59 million in FY 2023 to purchase research equipment at 77 institutions across 30 states.
Changes in the properties of organic materials undergoing transition between solid and liquid phases are employed in a variety of applications, including thermal energy storage, cooling, and actuation. The ability to regulate such phase transitions by light opens up new opportunities to achieve functions with a high spatial precision, triggered by the rapid, remotely applied, and non-invasive stimulus. This capability enables novel applications including photo-controlled heat storage, adhesion, actuation, and catalyst recovery, which the Han group investigates.
The DURIP award from the Air Force Office of Scientific Research (AFOSR) and the Department of Defense (DoD) will enable the Han team to build a new research capability on campus. A non-ambient, benchtop X-ray diffractometer, equipped with light sources and a heating/cooling stage, will allow the group to study how molecules change their geometry and intermolecular interaction in response to irradiation and temperature change. This will yield a deep understanding of photoswitch designs that undergo facile structural changes in solid phase, assisting the discovery and development of light-responsive functional materials.
Associate Professor of Physics Matthew Headrick was named by the American Physical Society as an Outstanding Referee for 2017. The award recognizes “scientists who have been exceptionally helpful in assessing manuscripts for publication in the APS journals”. Headrick, who works in string theory and related areas of theoretical physics, is one of 150 Outstanding Referees named this year, out of about 60,000 active referees for the APS journals. Headrick is not the only Brandeis physicist to have received this honor; Robert Meyer, now Emeritus Professor, was named an Outstanding Referee in 2011.
Headrick’s research is primarily focused on the intersection of quantum gravity, quantum field theory, and quantum information theory. He is specifically interested in information-theoretic aspects of holographic field theories (field theories that are dual to higher-dimensional gravitational theories), such as entanglement entropies and related quantities.
Hampton University and Brandeis University have formed a new initiative called the Partnership for Research and Education in Materials (PREM). Using a 5-year, $3 million grant from the National Science Foundation, the two universities have joined forces to foster interest in research science in under-represented groups of undergraduates.
A joint Pathway to Professorship (PtP) program will offer a path for under-represented research assistant professors to advance their research and possibly reach a tenure-track professorship at Brandeis or Hampton. These unique training positions could be filled by applicants in most disciplines including Biology, Chemistry, Physics, and Engineering. They involve one-year residences at Brandeis and Hampton Universities. Recruiting has started – interested applicants should start at the Hampton Career Opportunities website.
Shantanu Jadhav, assistant professor of Psychology and Neuroscience and one of our newest faculty members, has won the prestigious Sloan Research Fellowship from the Alfred P. Sloan Foundation.
Jadhav’s research focuses on how the hippocamus and the prefrontal cortex interact and communicate with each other. This activity influences the brain’s ability to learn, remember and make decisions.
More information about Shantanu Jadhav’s research and the Sloan Research Fellowship can be found at Brandeis NOW.
The guidelines for selecting the neuroscientists include: leadership, applicability (neuroscientists that have created technologies that have improved people’s lives); awards & recognition by the international science community and other notable accomplishments such as personal or educational achievements.
Marissa Kuzirian and Amy Ghiretti, graduate students in the lab of Dr. Suzanne Paradis, were each recently awarded Ruth L. Kirschstein National Research Service Awards for Individual Predoctoral Fellows (F31s) from the National Institutes of Health. Marissa’s 2.5-year award from the National Institute of Neurological Disorders and Stroke funds research to explore the role of Semaphorin4D and its receptor, PlexinB1, in regulating inhibitory synapse development and ultimately setting up proper neural connections in the mammalian CNS. Amy’s 2-year award from the National Institute on Drug Abuse funds a collaborative project between the Paradis, Lau, and Van Hooser labs here at Brandeis to elucidate the function of Rem2 in mediating experience-dependent changes in dendritic morphology in a living, intact animal system.
The basis for Marissa and Amy’s work comes from research into neurodevelopmental disorders such as Autism Spectrum Disorders (ASDs), as well as drug abuse and addiction. Proteins that regulate neurodevelopmental processes such as synapse development and dendritic morphology are important in both neurological disorders and drug addiction. Proper communication between neurons depends on the precise assembly and development of synaptic connections. The transmembrane protein Semaphorin4D (Sema4D) is necessary for proper GABAergic synapse formation, as knockdown of expression in the postsynaptic neuron by RNAi leads to a decrease in GABAergic synaptic density in cultured neurons (Paradis et al 2007). Marissa’s work will further explore this role of Sema4D in GABAergic synapse development.
Inhibitory synapses are identified in white along dendrites of a rat hippocampal neuron. Synapses are defined as sites of overlap between the postsynaptic protein GABAA receptor subunit γ2 (red) and the presynaptic protein GAD65 (blue) visualized by immunostaining. Neurons are visualized by immunostaining for MAP2 (green).
Marissa’s preliminary results demonstrate that adding the soluble, extracellular domain of Sema4D to cultured hippocampal neurons is sufficient to drive GABAergic synapse formation. This increase depends on the expression of Sema4D’s receptor, PlexinB1. Thus, Marissa’s work defines PlexinB1 as a novel receptor mediating GABAergic synapse formation in response to Sema4D in the mammalian CNS. The goal of Marissa’s project is to elucidate the role of Sema4D and its receptor, PlexinB1, in GABAergic synapse development. In experiments she proposed, she hypothesizes that Sema4D acts to initiate assembly of GABAergic synaptic proteins such as GABAA receptors and gephyrin through its receptor PlexinB1. This will be tested using a variety of imaging techniques in cultured hippocampal neurons, including confocal and time-lapse imaging, to measure the mobility and accumulation of GABAergic synaptic proteins in neurons after treatment with soluble Sema4D. The experiments will not only greatly expand our understanding of a novel receptor-ligand pair in GABAergic synapse development, it will inform as to some of the basic mechanisms underlying GABAergic synaptogenesis.
Molecular mechanisms, such as the Sema4D-PlexB1 interaction described above, are critical for the ability of the central nervous system (CNS) to respond to extracellular stimuli and make corresponding changes in the structure and function of a neuron. At the behavioral level, this plasticity allows an organism to respond to a changing environment appropriately in order to survive. At the level of individual neurons, this is reflected in changes in gene expression that occur in response to a variety of stimuli, including alterations in neuronal network activity. The goal of Amy’s work is to characterize a direct molecular link between changes in neuronal activity and changes in dendritic morphology.
A neuron in the optic tectum of a Xenopus tadpole; Green Fluorescent Protein expression allows the dendrites to be visualized.
Amy has previously implicated the protein Rem2, a type of signaling molecule known as a GTPase, as a mediator of such neurodevelopmental processes as excitatory synapse formation and dendritic morphology (Ghiretti & Paradis 2011). The expression of Rem2 in individual neurons is upregulated following increased neuronal activity, suggesting that it may serve as a direct link between changes in activity and corresponding changes in the structure and function of neurons. Her recently funded work will utilize Xenopus laevis tadpoles to study the effects of visual experience (by exposing the tadpoles to a light stimulus) on Rem2 expression, and in turn, how Rem2 mediates experience-dependent changes in the morphology of neurons in a region of the brain known as the optic tectum, where visual processing takes place. Ultimately, a full understanding of how Rem2 functions to shape the morphology of neurons in an intact system may help to inform knowledge of how the human brain changes as a result of neurological disorders or drug abuse, and aid in the development of more effective treatments to prevent these changes from occurring.
Former physics majors Keith Cheveralls ’09 and Daniel Beller ’10 and current physics major Netta Engelhardt ’11 have been awarded the prestigious National Science Foundation Graduate Research Fellowship. The fellowship recognizes and supports outstanding graduate students in the US who have demonstrated exceptional promise in science research. Keith is currently a first year graduate student at UC Berkeley; while at Brandeis he did his senior thesis with Professor Jane Kondev and was a co-author on a paper that appeared last year in the Proceedings of the National Academy of Sciences. Dan, a first year graduate student at the University of Pennsylvania, completed his senior thesis at Brandeis with Professor Zvonimir Dogic and Professor Robert Meyer. Currently, Dan is conducting research on liquid crystals in the group of Professor Randall Kamien at UPenn. Netta is currently doing her senior thesis with Professor Matthew Headrick, and is planning to attend graduate school in physics next year.
At the 2010 Brandeis commencement exercises this week, Assistant Professor of Biology Melissa Kosinski-Collins was awarded the Louis Dembitz Brandeis Prize for Excellence in Teaching. Melissa’s enthusiasm and energy in teaching are infectious, and her efforts in the development of our undergraduate teaching lab and other courses are vastly appreciated.
Congratulations to Grace Han, Assistant Professor of Chemistry and Landsman Career Development Chair in the Sciences. She has been awarded funds from the Department of Defense to purchase a bench-top X-ray diffraction instrument. This award is part of the DoD’s Defense University Research Instrumentation Program (DURIP) that will provide $59 million in FY 2023 to purchase research equipment at 77 institutions across 30 states.
urrigiano
Science at Brandeis 