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  • Date:26SundayJanuary 2020

    Quantifying Holocene rainfall and evaporation in East Asia

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    Time
    11:00
    Location
    Sussman Family Building for Environmental Sciences
    M. Magaritz Seminar Room
    Lecturer
    Yoni Goldsmith
    Hebrew University of Jerusalem
    Organizer
    Department of Earth and Planetary Sciences
    Contact
    Lecture
  • Date:26SundayJanuary 2020

    Mechanical interaction between cells in fibrous environments

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    Time
    11:00 - 12:00
    Location
    Perlman Chemical Sciences Building
    Room 404
    Lecturer
    Dr. Ayelet Lesman
    School of Mechanical Engineering, Faculty of Engineering, Tel-Aviv University
    Organizer
    Department of Materials and Interfaces
    Soft Matter and Biomaterials
    Contact
    AbstractShow full text abstract about Tissues are made up of cells and an extracellular matrix (EC...»
    Tissues are made up of cells and an extracellular matrix (ECM), a cross-linked network of fibers that exhibits complex mechanics. Cells actively alter the ECM structure and mechanics by applying contractile forces. These forces can propagate far into the matrix and allow for remote cellular sensing. We study experimentally and computationally how cell-generated forces are transmitted in fibrous environments, the associated physical mechanisms, and the ability of the propagated forces to support mechanical interaction between distant cells. Also, we demonstrate how the dynamic changes in the ECM structure can lead to improve transport of molecules traveling between the cells, facilitating mechano-biochemical interactions. Such long-range force interactions through the ECM can drive large-scale cooperative biological processes, such that occur during wound healing and morphogenesis. Our work can also provide design parameters for biomaterials used in tissue engineering applications.
    Lecture
  • Date:26SundayJanuary 2020

    Faculty Seminar

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    Time
    11:15 - 13:00
    Title
    On Parameterized Analysis and the Disjoint Paths Problem
    Location
    Jacob Ziskind Building
    Room 155
    Lecturer
    Meirav Zehavi
    Ben Gurion University
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of Parameterized Anaylsis leads both to deeper understanding of...»
    Parameterized Anaylsis leads both to deeper understanding of intractability results and to practical solutions for many NP-hard problems. Informally speaking, Parameterized Analysis is a mathematical paradigm to answer the following fundamental question: What makes an NP-hard problem hard? Specifically, how do different parameters (being formal quantifications of structure) of an NP-hard problem relate to its inherent difficulty? Can we exploit these relations algorithmically, and to which extent? Over the past three decades, Parameterized Analysis has grown to be a mature field of outstandingly broad scope with significant impact from both theoretical and practical perspectives on computation.

    In this talk, I will first give a brief introduction of the field of Parameterized Analysis. Then, I will discuss some recent work in this field, where I mainly address (i) problems at the core of this field, rooted at Graph Minors and Graph Modification Problems, and (ii) applications of tools developed in (i) in particular, and of parameterized analysis in general, to Computational Geometry and Computational Social Choice. Additionally, I will zoom into a specific result, namely, the first single-exponential time parameterized algorithm for the Disjoint Paths problem on planar graphs. An efficient algorithm for the Disjoint Paths problem in general, and on "almost planar" graphs in particular, is a critical part in the quest for the establishment of an Efficient Graph Minors Theory. As the Graph Minors Theory is the origin of Parameterized Analysis and ubiquitous in the design of parameterized algorithms, making this theory efficient is a holy grail in the field.
    Lecture
  • Date:26SundayJanuary 2020

    Chemical and Biological Physics Guest Seminar

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    Time
    14:00 - 15:00
    Title
    Non-Genetic “Optogenetics”: Silicon Based Bio-Interfaces for Multi-scale Optical Modulation
    Location
    Perlman Chemical Sciences Building
    Room 404
    Lecturer
    Dr Menahem (Hemi) Rotenberg
    The James Franck Institute, the University of Chicago
    Organizer
    Department of Chemical and Biological Physics
    Contact
    AbstractShow full text abstract about Bioelectronics for cellular interrogation requires a minimal...»
    Bioelectronics for cellular interrogation requires a minimally invasive introduction of an electrical probe to the cell. Despite tremendous developments in the field of electroceuticals in the past decades, the available technologies are still associated with major limitations. Micropipette electrodes, micro- and nanoelectrode arrays, and nano-field effect transistors allow intracellular access with extremely high spatial resolution. However, these technologies are substrate-bound, do not allow reconfigurable recording or stimulation, and lack deep tissue access, which limits their use to in vitro application. Optogenetics can offer numerous mechanistic insights into cellular processes, but its spatial resolution is limited, especially for 3D tissues. Moreover, it requires genetic modification, which limits its potential therapeutic applications. In this talk, I will present my recent studies of developing new approaches for bio-interfaces using silicon micro- and nanostructures for non-genetic optical modulation, spanning from sub cellular interrogation with extremely high spatial resolutions to whole organ optical modulation. For sub-cellular interrogation, we used tailored made photovoltaic silicon nanowires with p-i-n core-shell design. These nanowires were hybridized with living myofibroblasts and used as free sanding cell-silicon hybrids with leadless optical modulation capabilities. We used focused laser to perform intracellular electrical interrogation with high, sub-cellular spatial resolution. Thereafter, we used these hybrids to tackle a long-standing debate regarding electrical coupling between myofibroblasts and cardiomyocytes in vivo, by interrogating specific myofibroblasts within the 3D volume of the cardiac tissue. We also show this technology’s utility for neuronal investigation by hybridizing myelinating oligodendrocytes and interfacing them with neurons, allowing the investigation of calcium transients’ role in the myelination process with unprecedented spatial control. For whole organ interface we used flexible single crystalline silicon membranes, that were able to adhere and wrap around the heart and sciatic nerve. We used optical stimulation to perform heart pacing at different location on the heart, and sciatic nerve excitation. These results demonstrate potential biomedical applications for cardiac resynchronization therapy and sciatic nerve neuro-regenerative treatments.
    Lecture
  • Date:27MondayJanuary 2020

    Israeli Fly meeting 2020

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    Time
    08:00 - 08:00
    Location
    David Lopatie Conference Centre
    Kimmel Auditorium
    Chairperson
    Oren Schuldiner
    Contact
    Conference
  • Date:27MondayJanuary 2020

    Annual Pearlman lecture - Catalysts Live & Up Close: Hunting for the Hidden Chemistry in Catalysis

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    Time
    11:00 - 12:15
    Location
    Gerhard M.J. Schmidt Lecture Hall
    Lecturer
    Prof. Bert M. Weckhuysen
    University of Utrecht
    Organizer
    Faculty of Chemistry
    Contact
    Colloquia
  • Date:27MondayJanuary 2020

    Braginsky Center for the Interface between the Sciences and the Humanities

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    Time
    11:00
    Title
    Evolutions: Science as Storytelling
    Location
    Dolfi and Lola Ebner Auditorium
    Lecturer
    Prof. Oren Harman
    Science, Technology and Society, Bar Ilan UNiversity
    Organizer
    Braginsky Center for the Interface between Science and the Humanities
    Contact
    DetailsShow full text description of "Evolutions: Science as Storytelling" In this lec...»
    "Evolutions: Science as Storytelling"
    In this lecture I will present a creative project, Evolutions: Fifteen Myths That Explain Our World, in which I juxtapose ancient myths and modern science, to better understand both the differences between the two and their surprising commonalities. We’ll meet the Earth and the Moon presenting a cosmological view of motherhood, consider the meaning of sacrifice through the evolution of the whale, and see what the birth of language in our hominin past can teach us about the meaning of truth. Science may not solve our existential puzzles, but like the age-old legends, its magical discoveries can help us continue our never-ending search.

    Professor Oren Harman is Chair of the Graduate Program in Science, Technology and Society at Bar Ilan University and Senior Research Fellow at the Van Leer Institute. He was trained in history and biology at the Hebrew University, Oxford, and Harvard. His books have been translated into many languages and include The Man Who Invented the Chromosome, Evolutions: Fifteen Myths That Explain Our World, and The Price of Altruism, which won the Los Angeles Times Book Prize and was nominated for a Pulitzer prize. He lives in Jerusalem with is wife and two little children, and sings bass with the Tel Aviv Chamber Choir.
    Lecture
  • Date:27MondayJanuary 2020

    Computer Science Seminar

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    Time
    11:15 - 13:00
    Title
    Interaction is necessary for distributed learning with privacy or communication constraints
    Location
    Jacob Ziskind Building
    Room 155
    Lecturer
    Yuval Dagan
    MIT
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of Local differential privacy (LDP) is a model where users send...»
    Local differential privacy (LDP) is a model where users send privatized data to an untrusted central server whose goal it to solve some data analysis task. In the non-interactive version of this model the protocol consists of a single round in which a server sends requests to all users then receives their responses. This version is deployed in industry due to its practical advantages and has attracted significant research interest. Our main result is an exponential lower bound on the number of samples necessary to solve the standard task of learning a large-margin linear separator in the non-interactive LDP model. Via a standard reduction this lower bound implies an exponential lower bound for stochastic convex optimization and specifically, for learning linear models with a convex, Lipschitz and smooth loss. These results answer the questions posed in citep{SmithTU17,DanielyF18}. Our lower bound relies on a new technique for constructing pairs of distributions with nearly matching moments but whose supports can be nearly separated by a large margin hyperplane. These lower bounds also hold in the model where communication from each user is limited and follow from a lower bound on learning using non-adaptive emph{statistical queries}.

    Link: https://arxiv.org/abs/1911.04014

    Lecture
  • Date:27MondayJanuary 2020

    Singlet oxygen as an essential component in plant stress response

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    Time
    14:00
    Title
    PhD Thesis Defense - Room 690C - Floor 6
    Location
    Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer
    Tomer Chen
    Prof. Robert Fluhr's Lab., Dept. of Plant and Environmental Sciences, WIS
    Organizer
    Department of Plant and Environmental Sciences
    Contact
    DetailsShow full text description of Room 690C - Floor 6...»
    Room 690C - Floor 6
    Lecture
  • Date:27MondayJanuary 2020

    Inferring the dynamics of learning from sensory decision-making behavior

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    Time
    14:00
    Location
    Gerhard M.J. Schmidt Lecture Hall
    Lecturer
    Prof. Jonathan Pillow
    Dept of Psychology, Princeton University
    Organizer
    Department of Neurobiology
    Contact
    DetailsShow full text description of Prof. Jonathan Pillow is visiting as a Guest of "Studen...»
    Prof. Jonathan Pillow is visiting as a Guest of "Students-Invited Lecture Series in Brain Sciences" and will give 2 seminars.
    For more details please contact: Aharon Ravia tel: 6273 aharon.ravia@weizmann.ac.il

    For accessibility issues, please contact naomi.moses@weizmann.ac.il
    AbstractShow full text abstract about The dynamics of learning in natural and artificial environme...»
    The dynamics of learning in natural and artificial environments is a problem of great interest to both neuroscientists and artificial intelligence experts. However, standard analyses of animal training data either treat behavior as fixed, or track only coarse performance statistics (e.g., accuracy and bias), providing limited insight into the dynamic evolution of behavioral strategies over the course of learning. To overcome these limitations, we propose a dynamic psychophysical model that efficiently tracks trial-to-trial changes in behavior over the course of training. In this talk, I will describe recent work based on a dynamic logistic regression model that captures the time-varying dependencies of behavior on stimuli and other task covariates. We applied our method to psychophysical data from both human subjects and rats learning a sensory discrimination task. We successfully tracked the dynamics of psychophysical weights during training, capturing day-to-day and trial-to-trial fluctuations in behavioral strategy. We leverage the model's flexibility model to investigate why rats frequently make mistakes on easy trials, demonstrating that so-called "lapses" often arise from sub-optimal weighting of task covariates. Finally, I will describe recent work on adaptive optimal training, which combines ideas from reinforcement learning and adaptive experimental design to formulate methods for inferring animal learning rules from behavior, and using these rules to speed up animal training.
    Lecture
  • Date:28TuesdayJanuary 2020

    Chemical and Biological Physics Dept Seminar

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    Time
    11:00
    Title
    Wide-Field Single Photon-Counting Imaging for Fast and Highly Sensitive In Vivo Cell Tracking
    Location
    Perlman Chemical Sciences Building
    Room 404
    Lecturer
    Dr Rinat Ankri
    Postdoctoral Fellow, UCLA, CA
    Organizer
    Department of Chemical and Biological Physics
    Contact
    AbstractShow full text abstract about Biomolecular imaging at the preclinical stage is an essentia...»
    Biomolecular imaging at the preclinical stage is an essential tool in various biomedical research areas such as immunology, oncology or neurology. Among all modalities available to date, optical imaging techniques play a central role, while fluorescence, in particular in the NIR region of the spectrum, provides high sensitivity and high specificity with relatively cheap instrumentation. Several whole-body optical pre-clinical NIR imaging systems are commercially available. Instruments using continuous wave (CW or time-independent) illumination allow basic small animal imaging at low cost. However, CW techniques cannot provide fluorescence lifetime contrast, which allows to probe the microenvironment and affords an increased multiplexing power. In the first part of my talk I will introduce our single photon, time-gated, phasor-based fluorescence lifetime Imaging method which circumvents limitations of conventional techniques in speed, specificity and ease of use, using fluorescent lifetime as the main contrast mechanism.
    In the second part of my talk I will present the tracking and multiplexing of two different cell populations, based on their different lifetimes (following their fluorescent dyes-loading). Despite major advantages of optical based NIR imaging, the reason that NIR imagers are not clinically used, is that only very few such fluorescent molecules absorb and emit in the NIR (or in the shortwave infrared, SWIR region), and even fewer have favorable biological properties (and FDA approval). I will introduce small lung cancer and dendritic cells tracking using small polyethylene glycol/phosphatidylethanolamine (PEG–PE) micelles loaded with NIR dyes (using commercial dyes as well as dyes synthesized in Prof. Sletten’s lab, UCLA Chemistry Dept.). Micelles’ endocytosis into cells affords efficient loading and exhibits strong bio stability, enabling to track the loaded cells for several days using these formulations, even though dyes were diluted by cells division (leading to reduced dye concentration within the dividing cells). Moreover, fluorescent lifetime contrast (achieved through our time-gated imaging method), significantly improved these cells detection.
    These advances in NIR fluorescence based imaging open up new avenues toward NIR and SWIR imaging for biomedical applications, such as tracking and monitoring cells during immunotherapy and/or drug delivery (treatment monitoring) for various types of disease.
    Lecture
  • Date:28TuesdayJanuary 2020

    Catalyst Images, Imaging and Imagination: Visualizing Molecules and Atoms in Action on Catalytic Surfaces

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    Time
    11:00 - 12:00
    Location
    Helen and Milton A. Kimmelman Building
    Dov Elad Room
    Lecturer
    Prof. Bert M. Weckhuysen
    Inorganic Chemistry and Catalysis, Utrecht University
    Organizer
    Department of Organic Chemistry
    Contact
    AbstractShow full text abstract about Catalysts play a pivotal role in modern society since they e...»
    Catalysts play a pivotal role in modern society since they enable the production of chemicals and fuels that we rely on every day. The search for new and improved solid catalysts to speed up and access novel chemical reactions is a never-ending challenge, but has become increasingly important due to the environmental challenges that we are currently facing. For this purpose, constant improvements in synthesis methods are required in general, but more specifically, improvements in characterization methods in terms of spatiotemporal resolution is the key toward tailored catalytic reactions. In an ideal case, a real time visualization of the reactants, intermediates and reaction products on the surface of the catalyst is possible, allowing for a molecular movie of the catalytic reaction in space and time. Certain characterization techniques exist that are sensitive enough to measure the reactants at the reaction surface of the catalyst (e.g. vibrational spectroscopy). However, in order to really understand the catalytic behaviour, we need to move toward single molecules and atoms at the (sub-) nanometer scale. Improvements in this direction have already led to an increased understanding of the catalytic processes, but the combination of nanometer resolution in space and pico- to nanosecond resolution in time has remained largely elusive in the world of heterogeneous catalysis.
     In this lecture, I will discuss the state-of-the-art of time- and space-resolved spectroscopy and microscopy methods for catalysis research, and discuss the movement in the field toward the visualization of individual molecules at catalyst surfaces to construct the ultimate “molecular movie of sustainability” (Figure 1). Special emphasis will be on the compatibility of operando characterization techniques with the desired reaction environment (e.g. liquid or gas phase) and what we can do to ensure the spatiotemporal resolution is not hampered by the reaction requirements of the catalytic reactions. I will touch upon a variety of techniques, ranging from (time-resolved and surface-enhanced) vibrational spectroscopy, single molecule fluorescence, scanning probe techniques combined with optical and vibrational spectroscopy, as well as X-ray spectroscopy and microscopy.
    Lecture
  • Date:28TuesdayJanuary 2020

    New type-1 and type-3 microbial rhodopsins

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    Time
    11:30 - 12:30
    Location
    Nella and Leon Benoziyo Building for Biological Sciences
    Auditorium
    Lecturer
    Prof. Oded Beja
    Faculty of Biology, Technion-Israel Institute of Technology
    Organizer
    Department of Plant and Environmental Sciences
    Contact
    DetailsShow full text description of Hosts: Dr. Cathy Bessudo and Dr. Hadas Zehavi...»
    Hosts: Dr. Cathy Bessudo and Dr. Hadas Zehavi
    Lecture
  • Date:28TuesdayJanuary 2020

    Imaging single cells in live models for neurodevelopmental and sleep disorders

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    Time
    12:30
    Location
    Gerhard M.J. Schmidt Lecture Hall
    Lecturer
    Prof. Lior Applebaum
    Faculty of Life Sciences Bar Ilan University
    Organizer
    Department of Neurobiology
    Contact
    DetailsShow full text description of Host: Dr. Meital Oren meital.oren@weizmann.ac.il tel: 647...»
    Host: Dr. Meital Oren meital.oren@weizmann.ac.il tel: 6479
    For accessibility issues, please contact naomi.moses@weizmann.ac.il
    Lecture
  • Date:28TuesdayJanuary 2020

    Toward HCV vaccine - Structural studies of HCV E2 envelop glycoprotein that facilitates rational design of HCV vaccine.

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    Time
    14:00 - 15:00
    Location
    Helen and Milton A. Kimmelman Building
    Dov Elad Room
    Lecturer
    Dr. Netanel Tzarum
    HUJI
    Organizer
    Department of Structural Biology
    Contact
    Lecture
  • Date:28TuesdayJanuary 2020

    Department of Molecular Genetics Special guest seminar

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    Time
    14:00 - 15:00
    Title
    “Microtubule dynamics at synaptic contacts are modulated by neuronal activity and affected by oligomeric AB1-42"
    Location
    Arthur and Rochelle Belfer Building for Biomedical Research
    Botnar Auditorium
    Lecturer
    Prof. Francesca Bartolini
    Assistant professor Pathology and Cell Biology department, Columbia University Medical Center, NY, USA.
    Organizer
    Department of Molecular Genetics
    Guest Lecture
    Contact
    DetailsShow full text description of MTs, play key roles in neuronal function. In addition, synap...»
    MTs, play key roles in neuronal function. In addition, synaptic biphasic fluctuations of MT instability/stability and tubulin post-translational modifications (PTMs) are associated with memory formation and are disrupted in aging, indicating a primary role for the regulation of MT dynamics and tubulin PTMs in the maintenance of synaptic plasticity. In support of this model, we recently found that stabilization of dynamic MTs and induction of tubulin PTMs by the formin mDia1 contribute to oligomeric Aβ1-42 synaptotoxicity, and inhibition of MT dynamics alone is sufficient to promote tau hyperphosphorylation and tau dependent synaptotoxicity (Qu et al., J Cell Biol, 2017). To test whether these changes occur at synapses and are directly responsible for synapse loss, we have further developed microscopy assays that measure MT invasions into dendritic spines and MT contacts with single presynaptic boutons of hippocampal neurons in culture. Surprisingly, we found that dynamic MT plus ends preferentially grow near presynaptic boutons (Qu et al., Curr Biol, 2019), and rescue/nucleation at boutons is enhanced by neurotransmitter release or when neurons are challenged with oligomeric Aβ1-42, an activity mediated by tau. Our data underscore the existence of a previously uncharacterized formin-mediated pathway of synaptotoxicity and a subset of tau-dependent presynaptic dynamic MTs that respond to neurotransmission and excitotoxicity.
    Lecture
  • Date:28TuesdayJanuary 2020

    New methods for identifying latent manifold structure from neural data

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    Time
    14:00
    Location
    Gerhard M.J. Schmidt Lecture Hall
    Lecturer
    Prof. Jonathan Pillow
    Dept of Psychology, Princeton University
    Organizer
    Department of Neurobiology
    Contact
    DetailsShow full text description of Prof. Jonathan Pillow is visiting as a Guest of "Studen...»
    Prof. Jonathan Pillow is visiting as a Guest of "Students-Invited Lecture Series in Brain Sciences" and will give 2 seminars.
    For more details please contact: Aharon Ravia tel: 6273 aharon.ravia@weizmann.ac.il

    For accessibility issues, please contact naomi.moses@weizmann.ac.il
    AbstractShow full text abstract about An important problem in neuroscience is to identify low-dime...»
    An important problem in neuroscience is to identify low-dimensional structure underlying noisy, high-dimensional spike trains. In this talk, I will discuss recent advances for tackling this problem in single and multi-region neural datasets. First, I will discuss the Gaussian Process Latent Variable Model with Poisson observations (Poisson-GPLVM), which seeks to identify a low-dimensional nonlinear manifold from spike train data. This model can successfully handle datasets that appear high-dimensional with linear dimensionality reduction methods like PCA, and we show that it can identify a 2D spatial map underlying hippocampal place cell responses from their spike trains alone. Second, I will discuss recent extensions to Poisson-spiking Gaussian Process Factor Analysis (Poisson-GPFA), which incorporates separate signal and noise dimensions as well as a multi-region model with coupling between latent variables governing activity in different regions. This model provides a powerful tool for characterizing the flow of signals between brain areas, and we illustrate its applicability using multi-region recordings from mouse visual cortex.

    Lecture
  • Date:29WednesdayJanuary 2020

    Developmental Club Series 2019-20

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    Time
    10:00
    Title
    “Glia-neuron interactions facilitate axon pruning”
    Location
    Arthur and Rochelle Belfer Building for Biomedical Research
    Botnar Auditorium
    Lecturer
    Prof. Oren Schuldiner
    Organizer
    Department of Molecular Genetics
    Developmental Club
    Contact
    Lecture
  • Date:30ThursdayJanuary 2020

    New MRI methods to evaluate structure and function of the left atrium

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    Time
    09:30 - 10:30
    Location
    Gerhard M.J. Schmidt Lecture Hall
    Lecturer
    Prof. Dana C. Peters
    School of Medicine, Yale University
    Organizer
    Department of Materials and Interfaces
    The Helen and Martin Kimmel Institute for Magnetic Resonance
    Contact
    AbstractShow full text abstract about The left atrium is important as the site of many arrhythmias...»
    The left atrium is important as the site of many arrhythmias, is essential to the ventricle as a booster pump, and provides an early indicator of for many cardiovascular diseases.
    We have developed MR imaging methods for measuring remodeling of the left atrium including measurement and quantification of left atrial fibrosis, evaluation of function, volumes, strain, and diastolic indices of elevated filling pressure, which affect the atrium.
    Lecture
  • Date:30ThursdayJanuary 2020

    New MRI methods to evaluate structure and function of the left atrium

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    Time
    09:30 - 10:30
    Location
    Gerhard M.J. Schmidt Lecture Hall
    Lecturer
    Prof. Dana Peters
    Yale School of Medicine
    Organizer
    Department of Materials and Interfaces
    The Helen and Martin Kimmel Institute for Magnetic Resonance
    Contact
    Lecture

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