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אפריל 30, 2015
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Date:18חמישיינואר 2018כנסים
The 3rd meeting of the Israeli Breast Cancer Translational Research Group
More information שעה 08:00 - 08:00מיקום מרכז כנסים על-שם דויד לופאטייושב ראש Ruth Scherz-Shouvalמארגן המחלקה לפיזיקה של חלקיקים ואסטרופיזיקה , המחלקה לביולוגיה מבנית וכימיתדף בית -
Date:18חמישיינואר 2018הרצאה
Magnetic Resonance Seminar
More information שעה 09:30 - 09:30כותרת Magnetic Resonance Spectroscopy to Study Brains and its Metabolismמיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Dr. Malgorzata Marjanska
Center for Magnetic Resonance Research Minneapolisמארגן המחלקה לפיזיקה כימית וביולוגיתצרו קשר תקציר Show full text abstract about Magnetic resonance spectroscopy (MRS) is a non-invasive tech...» Magnetic resonance spectroscopy (MRS) is a non-invasive technique that allows the measurement of multiple metabolites in the brain in vivo at the same time. These MR visible metabolites are primarily located in the intracellular compartments and preferentially concentrated in certain cell types. For instance, N-acetylasparate and glutamate are predominantly located in neurons, total creatine (creatine + phosphocreatine) and choline containing compounds are found in both neuronal and glial cells, and myo-inositol is thought to be localized exclusively in astrocytes. In the first part of my presentation, I will focus on the application of 1H MRS to study aging of the brain and brain tumors. In the second part of my presentation, I will concentrate on hyperpolarized 13C work in the animal brain which focuses on validating the ability to quantitatively estimate the TCA cycle rate and examination of the effect of various levels of brain activity on the detection of metabolic products from hyperpolarized pyruvate. -
Date:18חמישיינואר 2018סימפוזיונים
Physics Colloquium
More information שעה 11:15 - 12:30מיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה TBA מארגן הפקולטה לפיזיקהצרו קשר תקציר Show full text abstract about TBA ...» TBA -
Date:18חמישיינואר 2018הרצאה
Chemical and Biological Physics dept Seminar
More information שעה 14:00 - 14:00כותרת Quantum disordered dynamics in the arrested relaxation of a molecular ultracold plasmaמיקום בניין פרלמן למדעי הכימיהמרצה Prof. Edward Grant
University of British Columbia, Vancouverמארגן המחלקה לפיזיקה כימית וביולוגיתצרו קשר תקציר Show full text abstract about Spontaneous avalanche to plasma splits the core of an ellips...» Spontaneous avalanche to plasma splits the core of an ellipsoidal Rydberg gas of nitric oxide. Ambipolar expansion first quenches the electron temperature of this core plasma. Then, long-range, resonant charge transfer from ballistic ions to frozen Rydberg molecules in the wings of the ellipsoid quenches the centre-of-mass ion/Rydberg molecule velocity distribution. This sequence of steps gives rise to a remarkable mechanics of self-assembly, in which the kinetic energy of initially formed hot electrons and ions drives an observed separation of plasma volumes. These
dynamics adiabatically sequester energy in a reservoir of mass transport, starting a process that anneals separating volumes to form an apparent glass of strongly coupled ions and electrons. Short-time electron spectroscopy provides experimental evidence for complete ionization. The long lifetime of this system, particularly its stability with respect to recombination and neutral dissociation, suggests that this transformation affords a robust state of arrested relaxation, far from thermal equilibrium. We argue that this state of the quenched ultracold plasma offers an experimental platform for studying quantum many-body physics of disordered systems in the long-time and finite energy-density limits. The qualitative features of the arrested state fail to
conform with classical models. Here, we develop a microscopic quantum description for the arrested phase based on an effective many-body spin Hamiltonian that includes both dipole-dipole and van der Waals interactions. This effective model offers a way to envision the quantum disordered non-equilibrium physics of this system.
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Date:21ראשוןינואר 2018הרצאה
Molecular Genetics Special Guest Seminar
More information שעה 10:00 - 11:00כותרת Seeing how life starts: Imaging the molecular and cell dynamics that form the early mouse embryoמרצה Dr. Nicolas Plachta
Institute of Molecular and Cell Biology A*STAR, Singaporeמארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:21ראשוןינואר 2018הרצאה
Governing microphysical parameters of shallow cumulus cloud ensembles and their parameterization using LES with bin microphysics
More information שעה 11:00 - 11:00מיקום בניין משפחת זוסמןמרצה Pavel Khain
Israel Meteorological Serviceמארגן המחלקה למדעי כדור הארץ וכוכבי הלכתצרו קשר -
Date:21ראשוןינואר 2018הרצאה
Molecular Genetics Departmental Seminar
More information שעה 13:00 - 13:00כותרת Cellular plasticity in the regenerating pancreasמיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Eran Yanowski מארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:22שניינואר 201825חמישיינואר 2018כנסים
New Insights in Tree Hydraulics
More information שעה 08:00 - 08:00מיקום המאיץ ע"ש קופלר במרכז קנדה לפיסיקה גרעיניתיושב ראש Dan Yakir -
Date:22שניינואר 2018סימפוזיונים
see in Hebrew
More information שעה 11:00 - 12:00כותרת "חינוך מדעי ככלי בונה קהילה"מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Dr. Liat Ben-David, CEO - Davidson מארגן הפקולטה לכימיהצרו קשר -
Date:22שניינואר 2018הרצאה
Bacterial transcription initiation gone awry: backtracking and pausing that lasts for durations comparable to the bacterial lifespan
More information שעה 14:00 - 15:00כותרת Special Guest Seminarמיקום בניין ע"ש מקס ולילאן קנדיוטימרצה Dr. Eitan Lerner
UCLAמארגן המחלקה לאימונולוגיה ורגנרציה ביולוגיתצרו קשר תקציר Show full text abstract about DNA transcription follows a chain of events: initiation, elo...» DNA transcription follows a chain of events: initiation, elongation and termination, in which initiation usually the slowest. This is mainly due to the process of RNA-polymerase (RNAP) proper binding to the promoter region on DNA and formation of the open transcription bubble, but also due to many failed attempts of the initially-transcribing complex (ITC) to escape the promoter region and transition to elongation. The latter involves multiple polymerization rounds of short transcript that are depleted from the complex after RNAP aborts a transcription trial to try again (abortive initiation). Traditionally, each round of abortive initiation was thought to be rapid. Using single-molecule FRET as well as magnetic tweezers nanomanipulation tools we have recently discovered an abortive initiation intermediate in which a short transcript on its way to be depleted, stabilizes the complex in a unique conformation with blockage of the nucleotide entry channel (the secondary channel). Even more intriguing was the fact that this paused-backtracked initiation intermediate was stabilized for ~4600 s. In addition, using single-molecule FRET measurements of multiple distances, we show that this long-lived paused-backtracked intermediate is associated with a conformation in the DNA transcription bubble different than any existing determined structure of the bacterial transcription initiation complex. Additionally, the initiation complex in this intermediate state avoids inhibition by the antibiotic molecule Rifampicin, for which there exist many different antibiotic-resistant mutants of RNAP. Therefore, it is important to understand how to stabilize this long-lived paused state as an antimicrobial strategy. This requires further structural determination, and because this intermediate state is heterogeneous, hence very hard to resolve using traditional structural biological techniques, we will discuss ways to resolve the possible structure through hybrid/integrative structural techniques, combining single-molecule spectroscopy and coarse-grained simulations. These findings open a new avenue in studying the mechanism of bacterial transcription initiation as well as new molecular therapeutic routes. -
Date:22שניינואר 2018הרצאה
Foundations of Computer Science Seminar
More information שעה 14:30 - 16:00כותרת Reproducibility in Randomized Log-spaceמיקום בניין יעקב זיסקינדמרצה Ofer Grossman
MITמארגן הפקולטה למתמטיקה ומדעי המחשב , המחלקה למדעי המחשב ומתמטיקה שימושית , המחלקה למתמטיקהצרו קשר -
Date:23שלישיינואר 2018הרצאה
Functions and regulation of 3D genome organisation in development and disease
More information שעה 10:00 - 11:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Prof. Francois Spitz
(Epi)Genomics of Animal Development Unit Department of Developmental and Stem Cell Biology Institut Pasteur Paris (France)מארגן מכון עזריאלי למערכות ביולוגיותצרו קשר תקציר Show full text abstract about The complex hierarchy of three-dimensional patterns that cha...» The complex hierarchy of three-dimensional patterns that characterize the 3D folding of mammalian chromosomes appears as an important element in controlling gene expression. At the megabase scale, chromosomes are partitioned into domains that define two main compartments, corresponding to transcriptionally active and inactive regions, respectively. Each compartment domain is itself composed of distinct domains characterized by increased self-interactions called topological domains (TADs). Recent high-resolution Hi-C approaches revealed a finer-scale organisation of the genome in smaller “contact domains”, often associated with loops linking specific points. At these different scales, the spatial organisation of the genome shows tight correlation with its chromatin structure and its transcriptional activity. However, while steady progress is being made in describing the 3D folding of the genome at increased resolution, the mechanisms that determine this folding, its dynamic properties and the functional implications of these emerging features are still poorly understood.
We use advanced genome tagging and engineering strategies, as well as targeted inactivation of factors involved in chromosomal folding to unravel the elements and mechanisms that drive the folding of large loci in specific yet dynamic conformations and their influence on gene expression. Our recent results show that the complex patterns of vertebrate HiC maps result from the superimposition of two distinct mechanisms: 1) a cohesin-independent mechanism which brings together regions of similar chromatin states 2) a cohesin-dependent folding that associate different small compartments into TADs. Within TADS, we show as well that enhancers are not acting in a homogeneous manner, but that their influence is distributed in complex patterns, partially guided by the underlying structure. I will discuss the different implications of these findings for our views of genome organisation. -
Date:23שלישיינואר 2018הרצאה
A deep 3D view into cells using cryo-scanning transmission electron tomography
More information שעה 10:00 - 11:00מיקום בניין לביוכימיה על שם נלה וליאון בנוזיומרצה Dr. Shron G. Wolf
Department of Chemical Research Support- WISמארגן המחלקה למדעים ביומולקולרייםצרו קשר תקציר Show full text abstract about CryoSTEM tomography (CSTET) is a novel combination [1-5] of ...» CryoSTEM tomography (CSTET) is a novel combination [1-5] of two well-established techniques: cryo-electron tomography (CET) and scanning transmission electron microscopy (STEM). Cryogenic fixation allows for the most faithful preservation of biological macromolecules, tissues and cells. By preserving the cryogenic temperature and maintaining a contamination-free environment inside the electron microscope, CET for such cryo-preserved specimens have resulted in major advances in their characterization [6]. However, due to technical constraints, sample thickness amenable to viewing by CET is limited (up to ~400 nm).
STEM provides a possibility for relieving these limitations because contrast and signal are produced incoherently. The natural limit for sample thickness is extended three-fold for CSTET, meaning that whole vitrified mammalian cells can be imaged at ~3-4 nm resolution for regions up to ~1 μm in thickness. For spreading cells, many inter- organelle contacts and morphologies can be studied. In addition, CSTET combined with Energy Dispersive X-ray Spectroscopy (EDX) allows for on-the-spot chemical characterization of cell contents.
References
1. Wolf, S.G., L. Houben, and M. Elbaum, Cryo-scanning transmission electron tomography of vitrified cells. Nature Methods, 2014. 11(4): p. 423-428.
2. Wolf, S.G., P. Rez, and M. Elbaum, Phosphorus detection in vitrified bacteria by cryo- STEM annular dark-field analysis. J Microsc, 2015. 260(2): p. 227-33.
3. Elbaum, M., S.G. Wolf, and L. Houben, Cryo-scanning transmission electron tomography of biological cells. MRS Bulletin, 2016. 41(07): p. 542-548.
4. Wolf, S.G., E. Shimoni, M. Elbaum, and L. Houben, STEM Tomography in Biology, in Cellular Imaging, Electron Tomography and Related Techniques, E.G. Hanssen, Editor. 2017, Springer, in press.
5. Wolf, S.G., Y. Mutsafi, T. Dadosh, T. Ilani, Z. Lansky, B. Horowitz, S. Rubin, M. Elbaum, and D. Fass, 3D visualization of mitochondrial solid-phase calcium stores in whole cells. Elife, 2017. 6: e29929.
6. Beck, M. and W. Baumeister, Cryo-Electron Tomography: Can it Reveal the Molecular Sociology of Cells in Atomic Detail? Trends Cell Biol, 2016. 26(11): p. 825-837. -
Date:23שלישיינואר 2018הרצאה
Students Seminar
More information שעה 11:15 - 12:30מיקום בניין וולפסון למחקר ביולוגימרצה Prof. Uri Alon's lab מארגן המחלקה לביולוגיה מולקולרית של התאצרו קשר -
Date:23שלישיינואר 2018הרצאה
Photorespiration is an adaptive response of plants to oxidative stress
More information שעה 11:30 - 11:30מיקום בניין לביוכימיה על שם נלה וליאון בנוזיומרצה Prof. Agepati S. Raghavendra
FNA, FASc, FTWAS, JC Bose National Fellow, School of Life Sciences, Dept. of Plant Sciences, University of Hyderabad, Hyderabad, Indiaמארגן המחלקה למדעי הצמח והסביבהצרו קשר -
Date:23שלישיינואר 2018הרצאה
Pay attention and learn from experience!: The transcriptional representation of experience and the role of the claustrum in attention
More information שעה 12:30 - 12:30מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Dr. Ami Citri
ELSC, The Hebrew University of Jerusalemמארגן המחלקה למדעי המוחצרו קשר -
Date:24רביעיינואר 2018הרצאה
Developmental Club Series 2017-2018
More information שעה 10:00 - 10:00כותרת How a key interface between the brain’s neuro-hormonal and vascular systems is assembledמיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Prof. Gil Levkowitz
Weizmann Institute of Scienceמארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:24רביעיינואר 2018הרצאה
Laser induced homogeneous and oriented ice nucleation probed by ultrafast X-ray pulses
More information שעה 11:00 - 12:00מיקום בניין פרלמן למדעי הכימיהמרצה Dr. Iftach Nevo
Dept. Materials and Interfaces, WISמארגן המחלקה לכימיה מולקולרית ולמדע חומריםצרו קשר תקציר Show full text abstract about Illumination of supercooled microliter water drops on a hydr...» Illumination of supercooled microliter water drops on a hydrophobic glass slide with pulsed ns-laser beams induces ice nucleation. The type of the ice nucleation, heterogeneous or homogeneous is determined by the illumination configuration. When analyzing the enhancement of the X-ray diffraction peaks from frozen drops and the first appearance of diffraction peak from the growing nuclei in a liquid drop by X-ray pulse after each laser pulse, a correlation to the polarization state is seen. This points toward the mechanism where the electric field defines preferred direction for water molecules to bind via the interaction between laser-induced dipoles. Furthermore, the latter observations also reveal particle ice attachment during growth. Finally, different illumination configurations yield freezing temperatures that can be higher by about 10 °C than from non-irradiated water drops. -
Date:25חמישיינואר 2018סימפוזיונים
Complexity-Theoretic Foundations of Quantum Supremacy Experiments
More information שעה 11:15 - 12:30מיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Scott Aaronson
UT Austinמארגן הפקולטה לפיזיקהצרו קשר תקציר Show full text abstract about In the near future, there will likely be special-purpose qua...» In the near future, there will likely be special-purpose quantum computers with 50 or so high-quality qubits and controllable nearest-neighbor couplings. In this talk, I'll discuss general theoretical foundations for how to use such devices to demonstrate "quantum supremacy": that is, a clear quantum speedup for *some* task, motivated by the goal of overturning the Extended Church-Turing Thesis (which says that all physical systems can be efficiently simulated by classical computers) as confidently as possible.
Based on joint work with Lijie Chen, https://arxiv.org/abs/1612.05903
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Date:25חמישיינואר 2018הרצאה
Optogenetic fMRI and the Investigation of Global Brain Circuit Mechanisms
More information שעה 14:00 - 14:00מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Jin Hyung Lee, PhD
Associate Professor of Neurology and Neurological Sciences, Bioengineering, Neurosurgery, and Electrical Engineering (Courtesy) Stanford Universityמארגן המחלקה למדעי המוחצרו קשר תקציר Show full text abstract about Understanding the functional communication across brain has ...» Understanding the functional communication across brain has been a long sought-after goal of neuroscientists. However, due to the widespread and highly interconnected nature of brain circuits, the dynamic relationship between neuronal network elements remains elusive. With the development of optogenetic functional magnetic resonance imaging (ofMRI), it is now possible to observe whole-brain level network activity that results from modulating with millisecond- timescale resolution the activity of genetically, spatially, and topologically defined cell populations. ofMRI uniquely enables mapping global patterns of brain activity that result from the selective and precise control of neuronal populations. Advances in the molecular toolbox of optogenetics, as well as improvements in imaging technology, will bring ofMRI closer to its full potential. In particular, the integration of ultra-fast data acquisition, high SNR, and combinatorial optogenetics will enable powerful systems that can modulate and visualize brain activity in real-time. ofMRI is anticipated to play an important role in the dissection and control of network-level brain circuit function and dysfunction. In this talk, the ofMRI technology will be introduced with advanced approaches to bring it to its full potential, ending with examples of dissecting whole brain circuits associated with neurological diseases utilizing ofMRI.
Short Bio:
Dr. Lee received her Bachelor’s degree from Seoul National University and Masters and Doctoral degree from Stanford University, all in Electrical Engineering. She is a recipient of the 2008 NIH/NIBIB K99/R00 Pathway to Independence Award, 2010 NIH Director’s New Innovator Award, 2010 Okawa Foundation Research Grant Award, 2011 NSF CAREER Award, 2012 Alfred P. Sloan Research Fellowship, 2012 Epilepsy Therapy Project award, 2013 Alzheimer’s Association New Investigator Award, 2014 IEEE EMBS BRAIN young investigator award, and the 2017 NIH/NIMH BRAIN grant award. As an Electrical Engineer by training with Neuroscience research interest, her goal is to analyze, debug, and engineer the brain circuit through innovative technology.
1. Hyun Joo Lee†, Andrew Weitz†, David Bernal-Casas, Ben A. Duffy, Mankin Choy, Alexxai Kravitz, Anatol Kreitzer, Jin Hyung Lee*, Activation of direct and indirect pathway medium spiny neurons drives distinct brain-wide responses, Neuron, 2016;91(2):412-424.
2. Jia Liu†, Ben A. Duffy†, David Bernal-Casas, Zhongnan Fang, Jin Hyung Lee*, Comparison of fMRI analysis methods for heterogeneous BOLD responses in block design studies, Neuroimage, 2017;147:390-408.
3. David Bernal-Casas, Hyun Joo Lee, Andrew Weitz, Jin Hyung Lee*, Studying brain circuit function with dynamic causal modeling for optogenetic fMRI, Neuron, 2017;93:522-532.