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February 21, 2016
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Date:08MondayJune 2020Lecture
Mean-field models for finite-size populations of spiking neurons
More information Time 10:00 - 10:00Lecturer Dr. Tilo Schwalger
Institute for Mathematics Technical University of BerlinOrganizer Department of Brain SciencesContact Abstract Show full text abstract about Firing-rate (FR) or neural-mass models are widely used for s...» Firing-rate (FR) or neural-mass models are widely used for studying computations performed by neural populations. Despite their success, classical firing-rate models do not capture spike timing effects on the microscopic level such as spike synchronization and are difficult to link to spiking data in experimental recordings. For large neuronal populations, the gap between the spiking neuron dynamics on the microscopic level and coarse-grained FR models on the population level can be bridged by mean-field theory formally valid for infinitely many neurons. It remains however challenging to extend the resulting mean-field models to finite-size populations with biologically realistic neuron numbers per cell type (mesoscopic scale). In this talk, I present a mathematical framework for mesoscopic populations of generalized integrate-and-fire neuron models that accounts for fluctuations caused by the finite number of neurons. To this end, I will introduce the refractory density method for quasi-renewal processes and show how this method can be generalized to finite-size populations. To demonstrate the flexibility of this approach, I will show how synaptic short-term plasticity can be incorporated in the mesoscopic mean-field framework. On the other hand, the framework permits a systematic reduction to low-dimensional FR equations using the eigenfunction method. Our modeling framework enables a re-examination of classical FR models in computational neuroscience under biophysically more realistic conditions. -
Date:08MondayJune 2020Colloquia
Chemistry Colloquium
More information Time 11:00 - 12:15Title An Adaptive Gravity Model for Insect SwarmsLocation https://weizmann.zoom.us/j/93522784475Lecturer Prof. Nir Gov
Department of Chemical and Biological PhysicsOrganizer Faculty of ChemistryContact -
Date:09TuesdayJune 2020Lecture
SARAF as a regulator of store-operated calcium entry
More information Time 10:00 - 10:45Location Nella and Leon Benoziyo Building for Biological SciencesLecturer Anna Meshcheriakova
Members - Dept. of Biomolecular Sciences-WISOrganizer Department of Biomolecular SciencesContact Abstract Show full text abstract about Calcium signaling serves as a means of regulation of virtual...» Calcium signaling serves as a means of regulation of virtually all processes in a cell throughout the life of an organism, from fertilization to death. One of the multiple aspects of calcium signaling is store-operated calcium entry (SOCE) that has been raising a great interest in the last 30 years. Disregarded first for its allegedly negligible effect on calcium changes inside a cell, it is being reconsidered nowadays as a ubiquitous phenomenon regulating pivotal processes, such as transcription, immune response and others. As other pathways of calcium signaling, SOCE is regulated by multiple proteins, required for adjusting calcium levels to current cellular needs. Among them is SARAF, a protein that has been shown to negatively regulate SOCE, thus preventing calcium excess inside a cell. I will try to elaborate on my attempts to decipher the mysterious mechanism of its regulation. -
Date:10WednesdayJune 2020Lecture
Developmental Club Series 2019-20 - cancelled
More information Time 10:00 - 10:00Location Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Prof. Eli Arama Organizer Department of Molecular GeneticsContact -
Date:11ThursdayJune 2020Conference
Weizmann- Garvan COVID-19 task force meeting (webinar)
More information Time 09:00 - 12:15Chairperson Ido Amit -
Date:14SundayJune 202016TuesdayJune 2020Conference
Making Connections Symposium 2020
More information Time 08:00 - 08:00Location The David Lopatie Conference CentreChairperson Ron Milo -
Date:14SundayJune 2020Lecture
Zoom Lecture: Designing In Situ Architectures in 3D Cell-Laden Hydrogels
More information Time 11:00 - 12:00Lecturer Prof. Dror Seliktar
Faculty of Biomedical Engineering, Technion Institute of TechnologyOrganizer Department of Molecular Chemistry and Materials ScienceContact Abstract Show full text abstract about One of the key advantages in using light-sensitive hydrogel ...» One of the key advantages in using light-sensitive hydrogel biomaterials is the ability to spatially structure cell scaffolds with three-dimensional mechanical cues that guide cellular morphogenesis. However, this has proven difficult because of the high toxicity associated with the cross-linking interactions. To overcome this challenge, we developed a new paradigm in micro-patterning using a reversible temperature-induced phase transition from liquid to solid vis-à-vis lower critical solubility temperature (LCST). This facilitates reduced transport kinetics of the polymer chains in solution, thus enabling crosslinking that is truly compatible with cell-laden 3D culture. Cellularized constructs were patterned to reveal a difference in morphogenesis between chemically crosslinked “stiffer” and physically crosslinked “softer” regions. Emphasizing the importance of mechanical heterogeneity in cellular morphogenesis, the results validate cutting-edge technology that can provide scientists with a robust set of tools for engineering cell and tissue growth in three dimensions. -
Date:14SundayJune 2020Lecture
Departmental Seminar by Aya Shkedy
More information Time 13:00 - 14:00Title "The intricate host-pathogen interactions: Protection from trypanosomes by the ApoL1 heritable mutations turns on specific cell death mechanisms"Organizer Department of Molecular GeneticsContact -
Date:16TuesdayJune 2020Lecture
Vesicle membrane ‘quarantine’ by mechanochemical insulation maintains apical membrane homeostasis during exocytosis
More information Time 10:00 - 11:00Location Nella and Leon Benoziyo Building for Biological SciencesLecturer Kamalesh Kumari
Members - Dept. of Biomolecular Sciences-WISOrganizer Department of Biomolecular SciencesContact Abstract Show full text abstract about Exocrine glands in our bodies secret copious amounts of carg...» Exocrine glands in our bodies secret copious amounts of cargo (like- sweat, saliva, digestive enzymes, chemokines, etc.) via. giant secretory vesicles, that are micron-scale in diameter. During the secretion of these giant vesicles, a large amount of the membrane is constantly added to the apical surface of the cells that can perturb its size, composition, and function that are vital to cell survival. Hemostatic maintenance of the cell surface in terms of size, shape, and composition is extremely challenging in the face of continuous secretion, which what we ventured to understand. We use a combination live-cell imaging and correlative light and electron microscopy (CLEM) approach, to uncover a novel a mechanism of exocytosis allowing the secretory cells to maintain membrane homeostasis during secretion. I will present to you data to describe what we call as - the crumpling and sequestration model of exocytosis. -
Date:16TuesdayJune 2020Lecture
Prof. Elisabetta Boaretto - Changing History by Changing Time
More information Time 12:00 - 12:00Title Changing History by Changing TimeLocation Dolfi and Lola Ebner AuditoriumLecturer Prof. Elisabetta Boaretto Organizer Communications and Spokesperson DepartmentHomepage Contact -
Date:18ThursdayJune 2020Conference
ECM, cytoskeleton and migration
More information Time 08:00 - 08:00Location The David Lopatie Conference CentreChairperson Oren Schuldiner -
Date:18ThursdayJune 2020Lecture
Real Time Quantum Sensing and Jüdisch-Deutsch
More information Time 09:30 - 10:30Lecturer Dr. Amit Finkler
Department of Chemical and Biological Physics, WISOrganizer Clore Institute for High-Field Magnetic Resonance Imaging and SpectroscopyContact Abstract Show full text abstract about Zoom Lecture: Link: https://weizmann.zoom.us/j/98578269625...» Zoom Lecture: Link: https://weizmann.zoom.us/j/98578269625
Magnetometry on the nanoscale range stands to benefit from quantum-enhanced sensing techniques, as these can potentially overcome classical noise limits. Specifically in our group we use a single nitrogen-vacancy center as an atomic-sized quantum sensor, with uT(nT) magnetic field sensitivity for dc(ac) fields.
Yet our measurement technique does rely on classical averaging due to a relatively poor signal-to-noise ratio. In this respect, a real-time response and feedback during signal acquisition based on (quantum) phase estimation promises to significantly reduce averaging time by using prior information obtained during the measurement.
I will present our current efforts in this direction, with the aim of performing adaptive sensing of nanoscale magnetic fields. Both static (dc) and dynamic (ac) problems will be addressed.
Finally, since this is after all a magnetic resonance seminar, I will present the relevant research context pertaining to electron spin resonance of small molecules and explain how we intend to reach the single molecule limit with this quantum sensing technology.
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Date:18ThursdayJune 2020Colloquia
TBA
More information Time 11:15 - 12:30Location Edna and K.B. Weissman Building of Physical SciencesLecturer Yuri Levin
ColumbiaOrganizer Faculty of PhysicsContact Abstract Show full text abstract about TBA ...» TBA -
Date:18ThursdayJune 2020Lecture
A new dawn for eosinophils in the tumor microenvironment
More information Time 14:00 - 15:00Location Nella and Leon Benoziyo Building for Biological SciencesLecturer Prof. Ariel Munitz Organizer Dwek Institute for Cancer Therapy ResearchContact -
Date:21SundayJune 2020Lecture
Departmental Seminar by Romano Strobelt
More information Time 13:00 - 13:45Title "A mechanism of hepatitis B virus (HBV) oncogenesis"Location Zoom: https://weizmann.zoom.us/j/92518717522Organizer Department of Molecular GeneticsContact -
Date:22MondayJune 2020Colloquia
Chemistry Colloquium
More information Time 11:00 - 12:15Title Shaping bio-tools out of the spins in waterLocation https://weizmann.zoom.us/j/96600250217Lecturer Prof. Lucio Frydman
WIS Department of Chemical and Biological PhysicsOrganizer Faculty of ChemistryContact -
Date:23TuesdayJune 2020Lecture
On the evolution of chaperones and co-chaperones and the exponential expansion of proteome complexity
More information Time 10:00 - 10:45Location Nella and Leon Benoziyo Building for Biological SciencesLecturer Saurav Malik
Members - Dept. of Biomolecular Sciences-WISOrganizer Department of Biomolecular SciencesContact Abstract Show full text abstract about We present a systematic analysis of how proteomes, and the c...» We present a systematic analysis of how proteomes, and the chaperones maintaining them, evolved across the Tree of Life (ToL). Proteomes have expanded exponentially. The total number of proteins per proteome expanded ~200-fold. Proteins became more complex: protein length increased ~3-fold, and multi-domain proteins expanded ~300-fold. Expansion also entailed the birth of completely new proteins. Along the ToL, the number of different folds had risen ~10-fold, also expanding fold-combinations by ~40-fold. Proteins prone to misfolding and aggregation (repeat and beta-rich proteins) proliferated ~600-fold. To maintain these exponentially expanding proteomes, core-chaperones, ranging from disaggregases to ATP-fueled unfolding/refolding machines, also evolved. However, today’s core-chaperones emerged already 3 billion years ago, and comprise ~0.3% of all genes from archaea to mammals. The challenge of supporting an exponential expansion of proteome complexity was met by higher cellular levels of core-chaperones, and continuous emergence of new co-chaperones that function cooperatively with core-chaperones, as a network. -
Date:24WednesdayJune 2020Lecture
Developmental Club Series 2019-20-cancelled
More information Time 10:00 - 10:00Location Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Prof. Ori Avinoam Organizer Department of Molecular GeneticsContact -
Date:24WednesdayJune 2020Lecture
Algebraic Geometry and Representation Theory Seminar
More information Time 16:30 - 18:00Title Restriction for general linear groups: the local non-tempered Gan-Gross-Prasad conjectureLecturer Kei Yuen Chan
Fudan UniversityOrganizer Faculty of Mathematics and Computer ScienceContact -
Date:25ThursdayJune 2020Lecture
Sparsity-based Methods for Rapid MRI
More information Time 09:30 - 10:30Lecturer Dr. Efrat Shimron
Department of Electrical Engineering and Computer Sciences (EECS) at UC BerkeleyOrganizer Clore Institute for High-Field Magnetic Resonance Imaging and SpectroscopyContact Abstract Show full text abstract about Zoom Lecture: https://weizmann.zoom.us/j/99058507421 Ma...» Zoom Lecture: https://weizmann.zoom.us/j/99058507421
Magnetic Resonance Imaging (MRI) is a superb imaging modality that provides high-quality images of the human body. However, one of its major limitations is the long acquisition time, which hinders the MRI clinical use. The acquisition time can be shortened by acquiring less data; however, this requires suitable methods for accurate image reconstruction from subsampled data, which is acquired with a sub-Nyquist rate.
In this seminar, four novel methods for image reconstruction from subsampled data will be presented. These methods build upon the well-established frameworks of Parallel Imaging (PI) and Compressed Sensing (CS), utilize a-priori knowledge about data sparsity, and address current limitations of PI-CS methods. The first two methods accelerate static MRI scans by introducing the Convolution-based Reconstruction (CORE) framework, which offers a parameter-free non-iterative reconstruction. Experiments with in-vivo 7T brain data demonstrated that these methods perform comparably to the well-established GRAPPA and l1-SPIRiT methods, with the advantage of shorter computation times and reduced need for parameter calibration. The next two developed methods accelerate dynamic MRI scans that provide temperature monitoring in High Intensity Focused Ultrasound (MRgHIFU) thermal ablation treatments. The developed methods enable rapid MR monitoring by reconstructing temperature changes from subsampled data. Validation experiments were performed with in-vivo data from clinical treatments of prostate cancer in humans; these showed that the proposed methods significantly outperform two state-of-the-art methods in the temperature reconstruction task