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  • Date:17רביעיינואר 2018

    Electron ratchets: producing currents without a bias

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    שעה
    11:00 - 12:00
    מיקום
    בניין פרלמן למדעי הכימיה
    Room 404
    מרצה
    Dr. Ofer Kedem
    Center for Bio-inspired Energy Science (CBES), Northwestern University
    מארגן
    המחלקה לחומרים ופני שטח
    צרו קשר
    תקצירShow full text abstract about Biological motors, such as the myosin-actin system respons...»

    Biological motors, such as the myosin-actin system responsible for muscle contraction, rectify Brownian motion using asymmetry and chemical energy. This type of rectification mechanism is called a ratchet, and has been implemented in artificial systems. Ratchets are non-equilibrium devices producing directed transport without an overall applied bias. Ratchets operate by breaking spatial and time-reversal symmetries through the application of a time-dependent potential with locally asymmetric features. In this talk, I will highlight some of our recent explorations of electron ratchets, using both experiment and theory. We find complex, unintuitive behaviors, with high sensitivity to structural and operating parameters, leading to effects such as current reversals. I will detail some promising features of a new experimental ratchet design, as well as a proposed photovoltaic device based on the ratchet principle.

    הרצאה
  • Date:17רביעיינואר 2018

    Algebraic Geometry and Representation Theory Seminar

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    שעה
    11:15 - 12:45
    כותרת
    Semisimplification of tensor categories
    מיקום
    בניין יעקב זיסקינד
    Room 290C
    מרצה
    Pavel Etingof
    MIT
    מארגן
    הפקולטה למתמטיקה ומדעי המחשב, המחלקה למדעי המחשב ומתמטיקה שימושית, המחלקה למתמטיקה
    צרו קשר
    הרצאה
  • Date:18חמישיינואר 2018

    The 3rd meeting of the Israeli Breast Cancer Translational Research Group

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    שעה
    08:00 - 08:00
    מיקום
    מרכז כנסים על-שם דויד לופאטי
    Kimmel Auditorium
    יושב ראש
    Ruth Scherz-Shouval
    מארגן
    בית ספר למחקר במתמטיקה ובמדעי המחשב על שם מורוס, הפקולטה לביוכימיה, הפקולטה לביולוגיה
    דף בית
    צרו קשר
    כנסים
  • Date:18חמישיינואר 2018

    Magnetic Resonance Seminar

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    שעה
    09:30
    כותרת
    Magnetic Resonance Spectroscopy to Study Brains and its Metabolism
    מיקום
    אולם הרצאות ע"ש גרהרד שמידט
    מרצה
    Dr. Malgorzata Marjanska
    Center for Magnetic Resonance Research Minneapolis
    מארגן
    המחלקה לפיסיקה כימית וביולוגית
    צרו קשר
    תקצירShow 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.
    הרצאה
  • Date:18חמישיינואר 2018

    Guest Seminar

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    שעה
    11:00 - 12:00
    כותרת
    Automated Verification of Infinite-State Systems with Certifiable Algorithms
    מיקום
    בניין יעקב זיסקינד
    Room 290C
    מרצה
    Shaull Almagor
    The Hebrew University
    מארגן
    הפקולטה למתמטיקה ומדעי המחשב, המחלקה למדעי המחשב ומתמטיקה שימושית, המחלקה למתמטיקה
    צרו קשר
    הרצאה
  • Date:18חמישיינואר 2018

    Physics Colloquium

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    שעה
    11:15 - 12:30
    מיקום
    בניין הפיסיקה ע"ש עדנה וק.ב. וייסמן
    Auditorium
    מרצה
    TBA
    מארגן
    הפקולטה לפיסיקה
    צרו קשר
    פרטים נוספיםShow full text description of 11:00 Coffee, Tea and more ...»
    11:00 Coffee, Tea and more
    תקצירShow full text abstract about TBA ...»
    TBA
    סימפוזיונים
  • Date:18חמישיינואר 2018

    Vision and Robotics Seminar

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    שעה
    12:15 - 13:30
    כותרת
    One-Sided Unsupervised Domain Mapping via Distance Correlations
    מיקום
    בניין יעקב זיסקינד
    Room 1
    מרצה
    Sagie Benaim
    Tel Aviv University
    מארגן
    הפקולטה למתמטיקה ומדעי המחשב, המחלקה למדעי המחשב ומתמטיקה שימושית, המחלקה למתמטיקה
    צרו קשר
    הרצאה
  • Date:18חמישיינואר 2018

    Geometric Functional Analysis and Probability Seminar

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    שעה
    13:30 - 15:30
    כותרת
    Double Seminar
    מיקום
    בניין יעקב זיסקינד
    Room 290C
    מרצה
    Oren Louidor (Technion) and Alexander Glazman (Tel Aviv).
    --
    מארגן
    הפקולטה למתמטיקה ומדעי המחשב, המחלקה למדעי המחשב ומתמטיקה שימושית, המחלקה למתמטיקה
    צרו קשר
    הרצאה
  • Date:18חמישיינואר 2018

    Chemical and Biological Physics dept Seminar

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    שעה
    14:00
    כותרת
    Quantum disordered dynamics in the arrested relaxation of a molecular ultracold plasma
    מיקום
    בניין פרלמן למדעי הכימיה
    Room 404
    מרצה
    Prof. Edward Grant
    University of British Columbia, Vancouver
    מארגן
    המחלקה לפיסיקה כימית וביולוגית
    צרו קשר
    תקצירShow 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.
    הרצאה
  • Date:21ראשוןינואר 201825חמישיינואר 2018

    New Insights in Tree Hydraulics

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    שעה
    08:00 - 08:00
    מיקום
    המאיץ ע"ש קופלר במרכז קנדה לפיסיקה גרעינית
    יושב ראש
    Dan Yakir
    צרו קשר
    כנסים
  • Date:21ראשוןינואר 2018

    Molecular Genetics Special Guest Seminar

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    שעה
    09:00 - 10:00
    כותרת
    Seeing how life starts: Imaging the molecular and cell dynamics that form the early mouse embryo
    מרצה
    Dr. Nicolas Plachta
    Institute of Molecular and Cell Biology A*STAR, Singapore
    מארגן
    המחלקה לגנטיקה מולקולרית
    צרו קשר
    הרצאה
  • Date:21ראשוןינואר 2018

    Governing microphysical parameters of shallow cumulus cloud ensembles and their parameterization using LES with bin microphysics

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    שעה
    11:00
    מיקום
    בניין משפחת זוסמן
    M. Magaritz Seminar Room
    מרצה
    Pavel Khain
    Israel Meteorological Service
    מארגן
    המחלקה למדעי כדור הארץ וכוכבי הלכת
    צרו קשר
    הרצאה
  • Date:21ראשוןינואר 2018

    Molecular Genetics Departmental Seminar

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    שעה
    13:00
    כותרת
    Cellular plasticity in the regenerating pancreas
    מיקום
    בניין ארתור ורושל בלפר למחקר ביורפואי
    Botnar Auditorium
    מרצה
    Eran Yanowski
    מארגן
    המחלקה לגנטיקה מולקולרית
    צרו קשר
    הרצאה
  • Date:22שניינואר 2018

    see in Hebrew

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    שעה
    11:00 - 12:00
    כותרת
    "חינוך מדעי ככלי בונה קהילה"
    מיקום
    אולם הרצאות ע"ש גרהרד שמידט
    מרצה
    CEO - Davidson
    מנכ״לית מכון דוידסון לחינוך מדעי- הזרוע החינוכית של מכון ויצמן למדע
    מארגן
    הפקולטה לכימיה
    צרו קשר
    סימפוזיונים
  • Date:22שניינואר 2018

    Bacterial transcription initiation gone awry: backtracking and pausing that lasts for durations comparable to the bacterial lifespan

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    שעה
    14:00 - 15:00
    כותרת
    Special Guest Seminar
    מיקום
    בניין ע"ש מקס ולילאן קנדיוטי
    Auditorium
    מרצה
    Dr. Eitan Lerner
    UCLA
    מארגן
    המחלקה לבקרה ביולוגית
    צרו קשר
    תקצירShow 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.
    הרצאה
  • Date:22שניינואר 2018

    Foundations of Computer Science Seminar

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    שעה
    14:30 - 16:00
    כותרת
    Reproducibility in Randomized Log-space
    מיקום
    בניין יעקב זיסקינד
    Room 290C
    מרצה
    Ofer Grossman
    MIT
    מארגן
    הפקולטה למתמטיקה ומדעי המחשב, המחלקה למדעי המחשב ומתמטיקה שימושית, המחלקה למתמטיקה
    צרו קשר
    הרצאה
  • Date:23שלישיינואר 2018

    Functions and regulation of 3D genome organisation in development and disease

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    שעה
    10:00 - 11:00
    מיקום
    בניין ארתור ורושל בלפר למחקר ביורפואי
    Botnar Auditorium
    מרצה
    Prof. Francois Spitz
    (Epi)Genomics of Animal Development Unit Department of Developmental and Stem Cell Biology Institut Pasteur Paris (France)
    מארגן
    מכון עזריאלי למערכות ביולוגיות
    צרו קשר
    תקצירShow 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.
    הרצאה
  • Date:23שלישיינואר 2018

    A deep 3D view into cells using cryo-scanning transmission electron tomography

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    שעה
    10:00 - 11:00
    מיקום
    בניין לביוכימיה על שם נלה וליאון בנוזיו
    Auditorium
    מרצה
    Dr. Shron G. Wolf
    Department of Chemical Research Support- WIS
    מארגן
    המחלקה למדעים ביומולקולריים
    צרו קשר
    תקצירShow 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.
    הרצאה
  • Date:23שלישיינואר 2018

    Photorespiration is an adaptive response of plants to oxidative stress

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    שעה
    11:30
    מיקום
    בניין לביוכימיה על שם נלה וליאון בנוזיו
    מרצה
    Prof. Agepati S. Raghavendra
    FNA, FASc, FTWAS, JC Bose National Fellow, School of Life Sciences, Dept. of Plant Sciences, University of Hyderabad, Hyderabad, India
    מארגן
    המחלקה למדעי הצמח והסביבה
    צרו קשר
    פרטים נוספיםShow full text description of Room 690C-Floor 6! Benoziyo for Biological Sciences Bldg. H...»
    Room 690C-Floor 6! Benoziyo for Biological Sciences Bldg.
    Hosts: Prof. Robert Fluhr and Dr. Assaf Gal
    הרצאה
  • Date:23שלישיינואר 2018

    Seminar in Geometry and Topology

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    שעה
    16:15 - 17:45
    כותרת
    Quantization of extremal metrics and applications
    מיקום
    בניין יעקב זיסקינד
    Room 290C
    מרצה
    Carl Tipler
    Universite de Bretagne Occidentale
    מארגן
    הפקולטה למתמטיקה ומדעי המחשב, המחלקה למדעי המחשב ומתמטיקה שימושית, המחלקה למתמטיקה
    צרו קשר
    הרצאה

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