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December 01, 2013
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Date:09ThursdayJanuary 2014Lecture
Carrier-envelope phase control over molecular dynamics in strong-field laser pulses
More information Time 11:15 - 12:30Location Edna and K.B. Weissman Building of Physical SciencesLecturer ITZIK BEN-ITZHAK
Kansas State UniversityOrganizer Faculty of PhysicsContact Abstract Show full text abstract about We have studied strong-field laser-induced fragmentation of ...» We have studied strong-field laser-induced fragmentation of the benchmark hydrogen molecule in sub 5 fs near infrared (IR) pulses. As the pulse duration approaches a single cycle, the molecular response depends on the waveform of the pulse. For a particularly simple example of the waveform which is characterized by the carrier-envelope phase (CEP) – the CEP can be used as a control knob for the ensuing molecular dynamics.
In this kind of experiments a “CEP-locking” or “CEP-tagging” technique is typically employed. The latter method was used in our studies as demonstrated in this talk by two examples. The first involves the study of CEP control over pathway interference in strong-field dissociation of H2+ [1,2], where a molecular-ion beam was used as the target. In the second example we explore the formation of long-lived excited H fragments from the fragmentation of an H2 target. As predicted by theory [3,4], the measurements show that the CEP steers protons of H2+ (or excited-hydrogen fragments H2) one way or the other along the laser polarization. Moreover, the fragmentation yield itself depends on the CEP.
Others contributing to this work:
N.G. Johnson, M. Zohrabi, B. Berry, U. Ablikim, B. Jochim, T. Severt, K. J. Betsch, K.D. Carnes,
Shuo Zeng, F. Anis, J. Hernández, Yujun Wang, and B.D. Esry
1Supported by the Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, Office of Science, US Department of Energy
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Date:09ThursdayJanuary 2014Lecture
What color is the sky?
More information Time 12:00 - 12:00Location Jacob Ziskind BuildingLecturer Yair Weiss
Hebrew University of JerusalemOrganizer Faculty of Mathematics and Computer ScienceContact -
Date:09ThursdayJanuary 2014Cultural Events
The Irony of Fate atty. Benny Don Yichye
More information Time 21:00 - 21:00Title The History of Jewish HumorLocation Dolfi and Lola Ebner AuditoriumContact -
Date:12SundayJanuary 201417FridayJanuary 2014Conference
Black Holes and Quantum Information Theory
More information Time 08:00 - 15:00Location The David Lopatie Conference CentreChairperson Micha BerkoozContact -
Date:12SundayJanuary 2014Lecture
Critical and gradual transitions in pattern-forming systems
More information Time 11:00 - 11:00Location Sussman Family Building for Environmental SciencesLecturer Dr. Golan Bel
Department of Solar Energy and Environmental Physics Blaustein Institutes for Desert Research Ben Gurion University of the NegevOrganizer Department of Earth and Planetary SciencesContact Abstract Show full text abstract about Critical transitions have attracted a great deal of attentio...» Critical transitions have attracted a great deal of attention due to their relevance to many natural and
social systems. Much research has been devoted to the characterization and identification of imminent
critical transitions. In spatially extended systems, the dynamics (close to and away from the critical
point) is more complicated due to the expansion, shrinking and coalescence of alternative-state
domains. Pattern-forming systems introduce additional complexity due to the patterned nature of one of
the stable states. In this talk, I will present several works in which we used the context of drylands
vegetation dynamics to study various aspects of this additional complexity: (i) Using a minimal model,
we showed that in systems exhibiting a bistability of a patterned state with a uniform state, a multitude
of intermediate stable localized states may appear, giving rise to step-like gradual shifts with extended
pauses at these states. This result suggests that a combination of abrupt-shift indicators and
gradual-shift indicators might be needed to unambiguously identify regime shifts. (ii) The existence of
these localized states in models for the dynamics of drylands vegetation and the response of the
systems described by these models to local perturbations will be discussed. (iii) We show how a
simplified version of a model for drylands vegetation dynamics can explain the emergence and the
observed dynamics of the spectacular phenomenon of “fairy circles” in southern Africa. If time
permits, I will present recent results demonstrating the effects of heterogeneity on the pattern
formation, survivability and resilience of water-limited vegetation.
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Date:12SundayJanuary 2014Lecture
The Euclid Space mission
More information Time 11:15 - 12:00Location Nella and Leon Benoziyo Physics BuildingLecturer Andrea Cimatti Organizer Nella and Leon Benoziyo Center for AstrophysicsContact -
Date:12SundayJanuary 2014Lecture
To be announced
More information Time 13:00 - 13:00Location Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Tomer Stern
Elazar Zelzer's group, Dept. of Molecular Genetics, WISContact -
Date:12SundayJanuary 2014Lecture
Boltzmann's Dog and Darwin's Finch: The statistical thermodynamics of self-replication and evolution
More information Time 13:15 - 13:15Location Dannie N. Heineman LaboratoryLecturer Prof. Jeremy England
Dept. of Physics MITOrganizer Clore Center for Biological PhysicsContact Abstract Show full text abstract about Living things operate according to well-known physical laws,...» Living things operate according to well-known physical laws, yet it is challenging to discern specific, non-trivial consequences of these constraints for how an organism that is a product of evolution must behave. Part of the difficulty here is that life lives very far from thermal equilibrium, where many of our traditional theoretical tools fail us. However, recent developments in nonequilibrium statistical mechanics may help light a way forward. The goal of this talk will be to explain some of these developments, and show how they offer a new perspective on the physics of self-replication, natural selection, and evolution. -
Date:12SundayJanuary 2014Lecture
The role of neutrophil infiltration for indcution of hepatic insulin resistance early in the course of High fat feeding
More information Time 15:00 - 16:00Location Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Prof. Rachel Levy
Faculty of Health Sciences, Soroka University Medical Center and Ben-Gurion University of the NegevContact -
Date:13MondayJanuary 2014Lecture
Adsorption of specially designed molecules on ionic substrates
More information Time 10:00 - 10:00Location Perlman Chemical Sciences BuildingLecturer Prof. Alex Shluger
Department of Physics and Astronomy, University College London, UKOrganizer Department of Molecular Chemistry and Materials ScienceContact -
Date:13MondayJanuary 2014Lecture
Clean nuclear-energ and climate-change
More information Time 11:15 - 12:00Location Nella and Leon Benoziyo Physics BuildingLecturer Frank Shu Organizer Nella and Leon Benoziyo Center for AstrophysicsContact Abstract Show full text abstract about We take a first principles approach to the science of climat...» We take a first principles approach to the science of climate change
and sustainable energy. We examine why carbon dioxide and
methane are worrisome greenhouse gases (GHG) despite being minor constituents
of the Earth's atmosphere, why the increase of extreme climate-related events is
exponentially sensitive to seemingly small increases in the mean temperature
of the surface of the Earth, and why it is so hard to displace fossil fuels
as the sources of primary energy generation by current clean-energy technologies.
We argue that climate mitigation now requires not only emitting less GHG,
but actually sources of negative carbon. We then present two technologies
researched by our group, supertorrefiers (STRs) and molten salt breeder reactors
(MSBRs), that taken together can result in a systematic lowering of GHG levels in
the Earth's atmosphere. STRs have the potential of creating solid, liquid, and gaseous
biofuels that are economically competitive with coal, petroleum, and natural gas.
MSBRs can replace, over the long-term, the light water reactors in current usage
with a walk-away safe, less expensive, more proliferation-resistant form of nuclear power,
with acceptable solutions for the problems of high-level and low-level nuclear waste.
Taken together, STRs and MSBRs allow a smooth and gradual transition away from fossil fuels
while exploiting the storage, transportation, and power-generation infrastructures
built up to support the fossil-fuel industry in a manner which can improve (if the biochar
is buried instead of burned), rather than degrade, the environment with increased use. -
Date:13MondayJanuary 2014Lecture
QIIME: Quantitative Insights Into Microbial Ecology
More information Time 14:15 - 16:00Location Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Prof. Rob Knight
Department of Chemistry and Biochemistry. University of ColoradoOrganizer Faculty of BiologyContact -
Date:13MondayJanuary 2014Lecture
Understanding the variability of growth in single cells
More information Time 14:15 - 14:15Location Edna and K.B. Weissman Building of Physical SciencesLecturer Nathalie Balaban
HUJIOrganizer Department of Physics of Complex SystemsContact Abstract Show full text abstract about Noise analysis in biological systems has greatly increased o...» Noise analysis in biological systems has greatly increased our understanding of the underlying cellular processes. Noise in the cell division process is often assumed to be responsible for variability in cell cycle duration, and to underlie heterogeneous responses of bacteria to antibiotics, as well as of cancer cells to drugs. We present a simple genetic module, known as a toxin-antitoxin motif, which exploits noise to generate a variability of growth in bacterial populations. More generally, we ask whether we can differentiate between stochastic and deterministic control of cell division variability. Using long-term time lapse microscopy to follow thousands of divisions and tools from non linear dynamics analysis, we show that the variability in cell-cycle duration in mammalian cells, which at first glance seems dominated by noise, is in fact controlled by a deterministic factor
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Date:13MondayJanuary 2014Lecture
מפגשים בחזית המדע
More information Time 19:30 - 21:15Location Davidson Institute of Science EducationOrganizer Science for All UnitHomepage Contact -
Date:14TuesdayJanuary 2014Lecture
The mechanobiology of cell adhesion
More information Time 10:00 - 11:00Location Wolfson Building for Biological ResearchLecturer Prof. Benny Geiger
Dept. of Molecular Cell Biology - WISOrganizer Department of Biomolecular SciencesContact -
Date:14TuesdayJanuary 2014Lecture
Gut microbes and their role in obesity and malnutrition
More information Time 10:00 - 10:00Location Arthur and Rochelle Belfer Building for Biomedical ResearchLecturer Prof. Rob Knight
Department of Chemistry and Biochemistry. University of ColoradoOrganizer Faculty of BiologyContact -
Date:14TuesdayJanuary 2014Colloquia
Life Sciences Colloquium
More information Time 11:00 - 11:00Title Mapping Developmental Pathways for Regenerative Medicine via Synthetic Modified mRNALocation Dolfi and Lola Ebner AuditoriumLecturer Prof. Kenneth Chien Contact -
Date:14TuesdayJanuary 2014Lecture
“FLP Mediated Reduction of CO2, CO and Flouroalkanes”
More information Time 11:00 - 11:00Title Organic Chemistry - Departmental SeminarLocation Helen and Milton A. Kimmelman BuildingLecturer Dr. Roman Dobrovetsky
Department of Chemistry University of TorontoOrganizer Department of Molecular Chemistry and Materials ScienceContact Abstract Show full text abstract about Frustrated Lewis pairs (FLPs) are sterically encumbered Lew...» Frustrated Lewis pairs (FLPs) are sterically encumbered Lewis acid/base combinations which do not form adducts, but successfully activate small molecules such as H2, CO2, N2O, NO etc. Recently, few examples of catalytic hydrogenation and hydroamination were shown employing FLP chemistry. However, despite this recent progress, the synthetic use of FLPs is still in its infancy.
In this talk some recent advancement of FLP chemistry will be presented e.g., a) catalytic reduction of CO2 to CO; b) Reduction of CO in CO/H2 mixture (analog of Fischer–Tropsch chemistry); c) Catalytic hydrodeflourination of flouroalkanes using Lewis acidic phosphonium.
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Date:14TuesdayJanuary 2014Lecture
"Studying the evolutionary constraints on metabolic pathway design"
More information Time 11:15 - 11:15Location Ullmann Building of Life SciencesLecturer Dr. Elad Noor
Dr. Ron Milo's lab, Plant Sciences Dept., Weizmann Institute of ScienceOrganizer Department of Plant and Environmental SciencesContact -
Date:14TuesdayJanuary 2014Lecture
Restoration of Sight with Photovoltaic Retinal Prosthesis
More information Time 12:30 - 12:30Location Gerhard M.J. Schmidt Lecture HallLecturer Dr. Yossi Mandel, MD, PhD, MHA
Ophthalmic Sciences and Engineering Lab Faculty of Life Sciences Bar Ilan UniversityOrganizer Department of Brain SciencesContact Abstract Show full text abstract about Retinal degenerative diseases, such as Retinitis Pigmentosa ...» Retinal degenerative diseases, such as Retinitis Pigmentosa (RP) and Age related Macular Degeneration (AMD), lead to loss of sight due to degeneration of photoreceptors, yet the inner retinal neurons which process the visual signals and relay them to the brain are relatively well preserved. Patterned electrical stimulation of the inner retinal neurons can elicit patterned visual perception, thereby restoring sight to some degree, as was demonstrated in recent clinical trials. However, current RF-powered implants require bulky electronics and trans-scleral cables, making implantation very complex and prone to failures. Even more importantly, low visual acuity achieved with the current implants limits their applicability to very small fraction of patients.
We have developed a wireless photovoltaic retinal prosthesis, in which camera-captured images are projected onto the retina using pulsed near-IR light. Each pixel in the subretinal implant directly converts pulsed light into local electric current to stimulate the nearby inner retinal neurons. Implants with pixel sizes of 280, 140 and 70µm were successfully implanted in the subretinal space of wild type and degenerate rats, and elicited robust cortical responses (eVEP) upon stimulation with NIR light. Amplitude of the eVEP increased with peak irradiance and pulse duration, and decreased with frequency in the range of 2-20Hz, similar to the visible light response.
Modular design of the arrays allows scalability to a large number of pixels, and combined with the ease of implantation, offers a promising approach to restoration of sight in patients blinded by retinal degenerative diseases.
Activation of the retinal bipolar cells by the implant makes our model a unique tool for studying retinal circuitry by comparing the response to stimuli elicited by the subretinal implant to those naturally elicited by visible light. I will discuss our novel approach to quantitative assessment of the visual acuity provided by the implant, as well as some unique aspects of prosthetic vision, such as stroboscopic stimulation. The theoretical and practical limits of visual acuity will be discussed along with future directions for restoration of sight to the blind.