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ספטמבר 12, 2014
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Date:28חמישינובמבר 2019סימפוזיונים
Attosecond Interferometry
More information שעה 11:15 - 12:30מיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Prof. Nirit Dudovich
WISמארגן הפקולטה לפיזיקהצרו קשר תקציר Show full text abstract about Attosecond science is a young field of research that has rap...» Attosecond science is a young field of research that has rapidly evolved over the past decade. The progress in this field opened a door into a new area of research that allows one to observe multi-electron dynamics in atoms, molecules and solids. One of the most important aspect of attosecond spectroscopy lies in its coherent nature. Resolving the internal coherence is a primary challenge in this field, serving as a key step in our ability to reconstruct the internal dynamics. As in many other branches in physics, coherence is resolved via interferometry. In this talk, I will describe advanced schemes for attosecond interferometry. The application of these schemes provides direct insights into a range of fundamental phenomena in nature, from tunneling and photoionization in atomic systems to ultrafast chiral phenomena in molecules. -
Date:01ראשוןדצמבר 2019הרצאה
Using cosmogenic 21Ne to quantify sediment residence time in large-scale fluvial systems throughout the geological record
More information שעה 11:00 - 11:00מיקום בניין משפחת זוסמןמרצה Michal Ben-Israel
The Hebrew University of Jerusalemמארגן המחלקה למדעי כדור הארץ וכוכבי הלכתצרו קשר תקציר Show full text abstract about Rivers are the most effective agent of erosion on earth, tra...» Rivers are the most effective agent of erosion on earth, transporting massive amounts of detrital and dissolved matter into depositional basins, making them a significant part of the rock cycle. To better understand the relationship between denudation of continents and the rivers that drain them, numerous studies examine the pathways of sediment transport through large drainage systems. However, due to the complex nature of sediment storage and transport dynamics in large-scale fluvial systems, the amount of time sediment spends in the sedimentary system is poorly constrained.
We measured cosmogenic 21Ne to quantify the exposure time of sediments within large-scale fluvial systems in large rivers: the modern Colorado river, the Miocene Hazeva River (~18 Ma), and the Lower Cretaceous (~130 Ma) Kurnub fluvial system. We observe that fluvial transport dynamics in large rivers are complex and that sediment transport time varies significantly and can last between very rapid (faster than our analytical measurement limitation ~103 yr) and 105 yr. To better understand the nature of fluvial transport dynamics in large rivers, we constructed a stochastic model that simulates repeated episodes of burial and exposure and examines the changes in concentrations of cosmogenic 26Al, 10Be, and 21Ne. We compared the simulated results to the concentrations measured in the Colorado River, and we predict that the total that sediment spent both buried and exposed – the residence time in large rivers is ~103-105 years. These observations suggest that the time-scales of sediment transport in large rivers have not changed significantly over the past 130 Myr and have remained significantly fast compared to other processes in the rock-cycle.
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Date:01ראשוןדצמבר 2019הרצאה
Departmental Seminar - Molecular Genetics Dept.
More information שעה 13:00 - 13:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:01ראשוןדצמבר 2019הרצאה
Active Matter: `active thermodynamics’ and the dynamics of biopolymer gels
More information שעה 13:15 - 13:15מיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Tomer Markovich
CTBP, Rice University and DAMTP, University of Cambridgeמארגן המחלקה לפיזיקה של מערכות מורכבותצרו קשר תקציר Show full text abstract about Active materials are composed of many components that can co...» Active materials are composed of many components that can convert energy from its environment (usually in the form of chemical energy) into directed mechanical motion. Time reversal symmetry is thus locally broken, leading to a variety of novel phenomena such as motility induced phase separation, reversal of the Ostwald process and flocking. Examples of active matter are abundant and range from living matter such as bacteria, actomyosin networks and bird flocks to Janus particles, colloidal rollers and macroscale driven chiral rods. Nevertheless, in many cases experiments on active materials exhibit equilibrium like properties (e.g., sedimentation of bacteria). In the first part of the talk I will try to answer the important question: how do we know a system is `active’? And if it is, can we have generic observables as in equilibrium thermodynamics? Can we measure how far it is from equilibrium? In the second part of the talk I will focus on examples of activity in biopolymer gels, such as the cytoskeleton of living cells. I will show some of the effects of active motors with emphasis on chiral motors. The latter does not have a unique hydrodynamic description, which one can utilize to gain access to the microscopic details of the complex motors using macroscopic measurements. I will also discuss non-motor activity and demonstrate how it can result in contractility, e.g., in the process of cell division. -
Date:01ראשוןדצמבר 2019הרצאה
Braginsky Center for the Interface between the Sciences and the Humanities, special guest lecture with Daniel Matt
More information שעה 16:00 - 17:00כותרת אלוהים והמפץ הגדול: גילוי ההרמוניה שבין מדע לרוחניותמיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Daniel Matt מארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:02שנידצמבר 2019הרצאה
A Song of Ice and Fire: Structural Results using Hot X-rays and Cold Electrons
More information שעה 11:00 - 12:00מיקום Benoziyo Biochemistry Auditoriumמרצה Prof. James Fraser
Department of Bioengineering and Therapeutic Sciences California Institute of Quantitative Biosciences (QB3)מארגן המחלקה למדעים ביומולקולרייםצרו קשר -
Date:02שנידצמבר 2019הרצאה
Special Guest Seminar
More information שעה 12:00 - 12:00כותרת “Using Systems Approaches to Understand the Mechanism of Disease”מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Nevan Krogan מארגן מכון עזריאלי למערכות ביולוגיותצרו קשר -
Date:02שנידצמבר 2019הרצאה
IMM Student seminar-Dr. Tzah Feldman (Dr. Liran Shlush’s la) and Serkalem Ayanaw (Prof. Steffen Jung's lab)
More information שעה 13:00 - 14:00מיקום בניין וולפסון למחקר ביולוגימארגן המחלקה לאימונולוגיה מערכתיתצרו קשר -
Date:02שנידצמבר 2019הרצאה
Networks mediating response and resistance to EGFR and other tyrosine kinase mediated therapies
More information שעה 14:00 - 15:00מיקום בניין ע"ש מקס ולילאן קנדיוטימרצה Dr. Sourav Bandyopadhyay מארגן המחלקה לאימונולוגיה ורגנרציה ביולוגיתצרו קשר -
Date:03שלישידצמבר 201905חמישידצמבר 2019כנסים
The 8th Annual Kahn Symposium- Frontiers in Biomedical Research,Michigan-Israel Partnership
More information שעה 08:00 - 08:00מיקום מרכז כנסים על-שם דויד לופאטייושב ראש Avraham Levy -
Date:03שלישידצמבר 2019הרצאה
Stem Cells, Regeneration and Aging Breakfast Seminar with Dr. Yonatan Stelzer, December 3rd at 9:00
More information שעה 09:00 - 10:00כותרת Stem Cells, Regeneration and Aging Breakfast Seminarמיקום בניין ע"ש מקס ולילאן קנדיוטימרצה Prof. Yonatan Stelzer מארגן המחלקה לאימונולוגיה ורגנרציה ביולוגיתצרו קשר -
Date:03שלישידצמבר 2019הרצאה
PhD Defense Seminar: The small molecule Chicago Sky Blue promotes heart repair following myocardial infarction in mice From high throughput screening to molecular mechanisms
More information שעה 10:00 - 10:00מיקום בניין וולפסון למחקר ביולוגימרצה Oren Yifa
Prof. Eldad Tzahor's lab, Department of Molecular Cell Biologyמארגן המחלקה לביולוגיה מולקולרית של התאצרו קשר -
Date:03שלישידצמבר 2019הרצאה
The Importance of Mechanistic Understanding for Developing Novel Umpolung Reactions and Solar Induced Processes
More information שעה 11:00 - 12:00מיקום בניין הלן ומילטון קימלמןמרצה Prof. Alex M. Szpilman
Department of Chemical Sciences, Ariel Universityמארגן המחלקה לכימיה מולקולרית ולמדע חומריםצרו קשר -
Date:03שלישידצמבר 2019הרצאה
Tailoring root exudation by plant-microbe interactions and long-distance signaling
More information שעה 11:30 - 12:30מיקום בניין לביוכימיה על שם נלה וליאון בנוזיומרצה Dr. Elisa Korenblum
At Prof. Asaph Aharoni's lab., Department of Plant and Environmental Sciencesמארגן המחלקה למדעי הצמח והסביבהצרו קשר -
Date:03שלישידצמבר 2019הרצאה
Rodents' social recognition: what the nose knows…and what it doesn't
More information שעה 12:30 - 12:30מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Shlomo Wagner
Sagol Department of Neurobiology University of Haifaמארגן המחלקה למדעי המוחצרו קשר תקציר Show full text abstract about The ability to recognize individual conspecifics, termed soc...» The ability to recognize individual conspecifics, termed social recognition, is crucial for survival of the individual, as it guides appropriate interactions with its social environment. In humans, social recognition can be based upon cues arriving from single sensory modalities. For example, humans can recognize a person just by looking at its face (visual modality) or hearing its voice (auditory modality). Such single-modality based social recognition seems to hold for other primates as well. Yet, how general is this ability among mammals is not clear.
Mice and rats, the main laboratory mammalian models in the field of neuroscience, are social species known to exhibit social recognition abilities, widely assumed to be mediated by stimulus-derived chemosensory cues received by the main and accessory olfactory systems of the subject. In the lecture, I will challenge this common assumption and show evidence that rodents' social recognition is based upon integration of olfactory, auditory and somatosensory cues, hence requires active behavior of the social stimuli. In that sense, social recognition in rodents seems to be fundamentally different from social recognition in humans.
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Date:03שלישידצמבר 2019הרצאה
Molecular basis of neuronal self-avoidance
More information שעה 14:00 - 15:00מיקום בניין הלן ומילטון קימלמןמרצה Dr. Rotem Rubinstein
Tel-Aviv Universityמארגן המחלקה לביולוגיה מבנית וכימיתצרו קשר -
Date:03שלישידצמבר 2019הרצאה
Spatial Transcriptomics: A getting started guide to the 10x genomics Visium Spatial Gene expression Solution
More information שעה 14:00 - 15:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Dr. Nicola Cahill
FAS 10x genomicsמארגן המחלקה לתשתיות מחקר מדעי החייםצרו קשר תקציר Show full text abstract about The Visium Spatial Gene Expression Solution from 10x Genomic...» The Visium Spatial Gene Expression Solution from 10x Genomics analyzes complete transcriptomes in
intact tissue sections, allowing you to discover genes and markers relevant to your research without
having to rely on known targets. Preserving spatial resolution offers critical information for
understanding the relationships between cellular function, phenotype, and location in the tissue. -
Date:03שלישידצמבר 2019הרצאה
The Braginsky Center for the Interface between the Sciences and the Humanities
More information שעה 15:00 - 16:00כותרת The Science of Memory and the Mechanisms of Mnemohistory - or, the fate of Jewish memory over >3300 yrsמיקום אולם ע"ש דולפי ולולה אבנרמרצה Prof. Yadin Dudai
Department of Neurobiology, WISמארגן המחלקה לפיזיקה כימית וביולוגיתצרו קשר תקציר Show full text abstract about From the vantage point of the Science of Memory, human cultu...» From the vantage point of the Science of Memory, human cultures can be considered as 'biocultural supraorganisms' that can store distributed experience-dependent, behaviorally-relevant representations over hundreds and thousands of years. I will describe cognitive and artefactual instruments that mediate encoding, consolidation, storage and retrieval of such cross-generational collective engrams in large human populations. Investigation of this type of long-duration memory is made possible by combining archeology, history and cognitive science.
I will focus on a model system for the analysis of long-duration cultural memory. This is the memory of the Jewish culture, that can be traced back ca. 3300 yr (i.e. ca. 130 generations) ago. I will zoom in on the core memory of this culture, i.e., the minimal set of cross-generational mnemonic items considered by members of that culture to define their collective origin, history and distinctiveness. Identifying a core memory item and tracing its fate over time can facilitate mechanistic understanding of remote as well as more recent collective memory.
I will present data and hypotheses concerning the encoding, transformation, persistence and reactivation of an early component of the core memory, that had amalgamated fact with fiction in its first ca. 1000 yrs before being put in writing ca. 2300 yrs ago in an information-dense text of only 63 Hebrew words. Its high-fidelity persistence relied on evolving procedural reactivations. Potential implications of this persistence mechanism for understanding remote memory in individuals will be discussed. In recent generations reactivation of this memory and its updating play a role in splitting Jewish cultural memory into sub-narratives that differ, inter alia, in geographical distribution and cultural signature. This enables data-based analysis of ongoing transformation of collective memory in a large distributed human population
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Date:05חמישידצמבר 2019הרצאה
Augmented methods for measuring one-bond heteronuclear spin pairs over a wide range of MAS frequencies
More information שעה 09:30 - 10:30מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Dr. Mukul Jain
WIS-TATA institute of Fundamental Research, Hyderabadמארגן המחלקה לכימיה מולקולרית ולמדע חומריםצרו קשר תקציר Show full text abstract about Measuring quantitative distances are important for studyin...»
Measuring quantitative distances are important for studying the structural properties of molecules at an atomic scale. Dipole-dipole coupling encodes for distance information between spin pairs. Additionally, the anisotropy of dipole-dipole coupling is also very sensitive to the sub-microsecond dynamics occurring in the molecules, and therefore can be used to estimate it. Rotational Echo Double Resonance (REDOR) and Correlation of Dipolar coupling and Chemical shift (DIPSHIFT) experiments are the most preferred experiments for measuring distances between a heteronuclear spin pair using Magic angle spinning (MAS) solid-state NMR. But these experiments can be used only for a small range of coupling strengths depending on the MAS frequency of the experiment. In the talk, I will discuss the latest developments we have made for measuring a wide range of coupling strengths using REDOR over a wide range of MAS frequencies. Further, I will also show that REDOR and DIPSHIFT are different realizations of a same experiment and this unification comes naturally out of our augmented REDOR sequence. Further, I will discuss a method to perform REDOR experiments with low radiofrequency amplitude pulses at MAS frequencies larger than 80~kHz. This method extends the application of REDOR and DIPSHIFT at very fast MAS frequencies, where the radiofrequency amplitude requirement becomes too high for nuclei other than 1H. Overall, the methods discussed here allow for measuring dipole-dipole coupling between heteronuclear spin-pairs over a wider range of MAS frequencies.
References:
1. T. Gullion and J. Schaefer, Journal of Magnetic Resonance, 1989.
2. M. G. Munowitz et al., Journal of American Chemical Society, 1981.
3. M. Hong et al., Journal of Magnetic Resonance, 1997.
4. P. Schanda et al., Journal of Magnetic Resonance, 2019.
5. M. G. Jain et al., Journal of Chemical Physics, 2017.
6. M. G. Jain et al., Journal of Chemical Physics, 2019.
7. M. G. Jain et al., Journal of Magnetic Resonance, 2019.
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Date:05חמישידצמבר 2019סימפוזיונים
What Processes Shape the Disks of Galaxies?
More information שעה 11:15 - 12:30מיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Hans-Walter Rix
Max Planck Institute for Astronomyמארגן הפקולטה לפיזיקהצרו קשר תקציר Show full text abstract about The Milky Way, as a very average spiral galaxy, can serve as...» The Milky Way, as a very average spiral galaxy, can serve as a galaxy model organism to tell us which physical processes shape
the current structure and stellar content of galaxies: what sets the overall radial profile of the disk,
which the present-day orbital of any star, and how much formation memory does the Milky Way's disk retain?
We can now draw on global Galactic stellar surveys that constrain orbits, abundances and ages.
I will show how modelling these data now shows that global radial orbit migration is a very strong effect that
decisively shapes the structure of the Milky Way's disk. If the Milky Way is typical in this respect this
explains why galaxy disk profiles are exponential. And I will also sketch how data from the Gaia mission
can now tell us in far more detail the mechanisms that drive orbit evolution throughout our disk.