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פברואר 21, 2016
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Date:08שנייוני 2020הרצאה
Mean-field models for finite-size populations of spiking neurons
More information שעה 10:00 - 10:00מרצה Dr. Tilo Schwalger
Institute for Mathematics Technical University of Berlinמארגן המחלקה למדעי המוחצרו קשר תקציר 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:08שנייוני 2020סימפוזיונים
Chemistry Colloquium
More information שעה 11:00 - 12:15כותרת An Adaptive Gravity Model for Insect Swarmsמיקום https://weizmann.zoom.us/j/93522784475מרצה Prof. Nir Gov
Department of Chemical and Biological Physicsמארגן הפקולטה לכימיהצרו קשר -
Date:09שלישייוני 2020הרצאה
SARAF as a regulator of store-operated calcium entry
More information שעה 10:00 - 10:45מיקום בניין לביוכימיה על שם נלה וליאון בנוזיומרצה Anna Meshcheriakova
Members - Dept. of Biomolecular Sciences-WISמארגן המחלקה למדעים ביומולקולרייםצרו קשר תקציר 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:10רביעייוני 2020הרצאה
Developmental Club Series 2019-20 - cancelled
More information שעה 10:00 - 10:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Prof. Eli Arama מארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:11חמישייוני 2020כנסים
Weizmann- Garvan COVID-19 task force meeting (webinar)
More information שעה 09:00 - 12:15יושב ראש Ido Amit -
Date:14ראשוןיוני 202016שלישייוני 2020כנסים
Making Connections Symposium 2020
More information שעה 08:00 - 08:00מיקום מרכז כנסים על-שם דויד לופאטייושב ראש Ron Milo -
Date:14ראשוןיוני 2020הרצאה
Zoom Lecture: Designing In Situ Architectures in 3D Cell-Laden Hydrogels
More information שעה 11:00 - 12:00מרצה Prof. Dror Seliktar
Faculty of Biomedical Engineering, Technion Institute of Technologyמארגן המחלקה לכימיה מולקולרית ולמדע חומריםצרו קשר תקציר 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:14ראשוןיוני 2020הרצאה
Departmental Seminar by Aya Shkedy
More information שעה 13:00 - 14:00כותרת "The intricate host-pathogen interactions: Protection from trypanosomes by the ApoL1 heritable mutations turns on specific cell death mechanisms"מארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:16שלישייוני 2020הרצאה
Vesicle membrane ‘quarantine’ by mechanochemical insulation maintains apical membrane homeostasis during exocytosis
More information שעה 10:00 - 11:00מיקום בניין לביוכימיה על שם נלה וליאון בנוזיומרצה Kamalesh Kumari
Members - Dept. of Biomolecular Sciences-WISמארגן המחלקה למדעים ביומולקולרייםצרו קשר תקציר 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:16שלישייוני 2020הרצאה
פרופ' אליזבטה בוארטו - שינוי ההיסטוריה דרך שינוי הזמן
More information שעה 12:00 - 12:00כותרת שינוי ההיסטוריה דרך שינוי הזמןמיקום אולם ע"ש דולפי ולולה אבנרמרצה Prof. Elisabetta Boaretto מארגן המחלקה לתקשורת ודוברותדף בית צרו קשר -
Date:18חמישייוני 2020כנסים
ECM, cytoskeleton and migration
More information שעה 08:00 - 08:00מיקום מרכז כנסים על-שם דויד לופאטייושב ראש Oren Schuldiner -
Date:18חמישייוני 2020הרצאה
Real Time Quantum Sensing and Jüdisch-Deutsch
More information שעה 09:30 - 10:30מרצה Dr. Amit Finkler
Department of Chemical and Biological Physics, WISמארגן מכון קלור לדימות וספקטרוסקופיה של תהודה מגנטית בעוצמות גבוהותצרו קשר תקציר 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:18חמישייוני 2020סימפוזיונים
TBA
More information שעה 11:15 - 12:30מיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Yuri Levin
Columbiaמארגן הפקולטה לפיזיקהצרו קשר תקציר Show full text abstract about TBA ...» TBA -
Date:18חמישייוני 2020הרצאה
A new dawn for eosinophils in the tumor microenvironment
More information שעה 14:00 - 15:00מיקום בניין לביוכימיה על שם נלה וליאון בנוזיומרצה Prof. Ariel Munitz מארגן המכון לחקר הטיפול בסרטן עש דואקצרו קשר -
Date:21ראשוןיוני 2020הרצאה
Departmental Seminar by Romano Strobelt
More information שעה 13:00 - 13:45כותרת "A mechanism of hepatitis B virus (HBV) oncogenesis"מיקום Zoom: https://weizmann.zoom.us/j/92518717522מארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:22שנייוני 2020סימפוזיונים
Chemistry Colloquium
More information שעה 11:00 - 12:15כותרת Shaping bio-tools out of the spins in waterמיקום https://weizmann.zoom.us/j/96600250217מרצה Prof. Lucio Frydman
WIS Department of Chemical and Biological Physicsמארגן הפקולטה לכימיהצרו קשר -
Date:23שלישייוני 2020הרצאה
On the evolution of chaperones and co-chaperones and the exponential expansion of proteome complexity
More information שעה 10:00 - 10:45מיקום בניין לביוכימיה על שם נלה וליאון בנוזיומרצה Saurav Malik
Members - Dept. of Biomolecular Sciences-WISמארגן המחלקה למדעים ביומולקולרייםצרו קשר תקציר 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:24רביעייוני 2020הרצאה
Developmental Club Series 2019-20-cancelled
More information שעה 10:00 - 10:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Prof. Ori Avinoam מארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:24רביעייוני 2020הרצאה
Algebraic Geometry and Representation Theory Seminar
More information שעה 16:30 - 18:00כותרת Restriction for general linear groups: the local non-tempered Gan-Gross-Prasad conjectureמרצה Kei Yuen Chan
Fudan Universityמארגן הפקולטה למתמטיקה ומדעי המחשבצרו קשר -
Date:25חמישייוני 2020הרצאה
Sparsity-based Methods for Rapid MRI
More information שעה 09:30 - 10:30מרצה Dr. Efrat Shimron
Department of Electrical Engineering and Computer Sciences (EECS) at UC Berkeleyמארגן מכון קלור לדימות וספקטרוסקופיה של תהודה מגנטית בעוצמות גבוהותצרו קשר תקציר 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
