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ינואר 01, 2015
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Date:16שנידצמבר 2024סימפוזיונים
Molecular junctions with semimetal contacts: a promising milestone on the roadmap to molecular thermoelectricity
More information שעה 11:00 - 12:15מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Yoram Selzer
Nano Center, TAUמארגן המחלקה לכימיה מולקולרית ולמדע חומריםדף בית צרו קשר תקציר Show full text abstract about The efficiency of a thermoelectric (TE) device depends on ...»
The efficiency of a thermoelectric (TE) device depends on the extent to which, in response to a given temperature gradient, its electron/hole transport symmetry at the Fermi level is broken. This requirement makes molecular junctions highly promising for TE applications due to their non-linear transmission properties. Yet, in the absence of an efficient method to tune the position of the Fermi level within the transmission landscape of these junctions, the Seebeck values of metal-molecules-metal junctions are typically |S|≤50μV/K, while based on their electrical and thermal conductance, it should be |S|≥1mV/K to be relevant for applications. I will describe our effort to reach this goal, which recently has culminated in molecular junctions with the semimetal Bismuth (Bi) as one of their leads and with |S| in the required mV/K range. Unlike the conventional approach to tweak the transmission properties by modifying the structure of the molecules, here the high Seebeck is a result of molecularly induced deterministic changes in the density of states within the Bi lead in the form of quantized 2D interfacial states, that in turn result in highly non-linear transport properties. I will argue that this effect is just one glimpse into the very rich and complex terra incognita of molecular layers on semimetals. -
Date:16שנידצמבר 2024הרצאה
Foundations of Computer Science Seminar
More information שעה 11:15 - 12:15כותרת Accountability in Threshold Cryptographyמיקום בניין יעקב זיסקינד
Room 1 - 1 חדרמרצה Lior Rotem
Stanfordמארגן המחלקה למדעי המחשב ומתמטיקה שימושיתצרו קשר תקציר Show full text abstract about Threshold cryptography has been fundamental to secure distri...» Threshold cryptography has been fundamental to secure distributed protocols for over three decades. However, it often comes at the expense of accountability: when secret information is shared among multiple parties, it can be difficult to determine who is at
fault if this information is leaked or misused.
In this talk, I will present a recent line of works that demonstrate that this trade-off is not inherent—we can indeed build accountable threshold cryptosystems. Most of the talk will focus on accountability in secret sharing. Suppose Alice uses a t-out-of-n secret sharing scheme to store her secret key on n servers. This guarantees that the servers learn nothing about her secret key, even if t-1 of them collude. But what happens if some servers decide to sell their shares? In this case, Alice should be able to hold them accountable; otherwise, they have a risk-free incentive to sell her shares. A secret sharing scheme that allows Alice to trace the leak back to the corrupted servers is called a traceable secret sharing scheme. I will present new definitions and practical constructions for traceable secret sharing, based on the natural and widely-used schemes of Shamir and Blakley. -
Date:17שלישידצמבר 2024הרצאה
Global virus outbreaks: Interferons as 1st responders
More information שעה 09:30 - 10:30מיקום בניין לביוכימיה על שם נלה וליאון בנוזיו
Auditorium room 191cמרצה Prof. Eleanor N. Fish
Dept. of Immunology, University of Toronto, Canadaמארגן המחלקה למדעים ביומולקולרייםצרו קשר תקציר Show full text abstract about Viral infections pose a major threat to human health. Vaccin...» Viral infections pose a major threat to human health. Vaccines protect from specificinfections, yet newly emerging or pandemic viral strains that exhibit genetic drift or reassortmentof genes preclude immediate responses using a vaccine strategy. Moreover, for SARS CoV-2,although current vaccines reduce severity of disease, they do not protect from re-infection,resulting in persistent community transmission and outbreaks. The emergence of drug resistancealso mitigates against pathogen-specific antiviral drugs. A complementary strategy focusing onthe host not the pathogen is the basis for development of broad-spectrum antivirals.Our immediate response to any and all virus infections is the immediate production of interferon(IFN). Data reveal that the robustness of an IFN response to respiratory infections, determinesthe outcome – an aggressive or mild infection. We provide evidence that an IFN response to viralinfection, and/or IFN treatment, induces an activated phenotype in target cells that results in anantiviral state and an optimized innate immune response, regardless of the virus. We extendedthese findings to examine the therapeutic potential of IFN treatment in hospitalized individualsinfected with SARS and showed that IFN treatment accelerated viral clearance and reduced lungabnormalities. Similarly, using human lung explants, IFN treatment cleared infection againstH5N1 avian and pandemic H1N1 influenza strains. During the Ebola virus outbreak in WestAfrica, we conducted a clinical study in Guinea and provided evidence of increased survivalassociated with IFN treatment. At the start of the COVID-19 pandemic we undertook a clinicalstudy in Wuhan, China, providing evidence that early treatment with an inhaled IFN acceleratedviral clearance, reduced inflammation and also reduced lung abnormalities. Given that limitingtransmission is the solution to shutting down any outbreak, we next conducted a clinical trial todetermine whether IFN treatment of SARS CoV-2 exposed, but uninfected individuals, wouldprotect from infection. We provide evidence that prophylactic treatment with IFN limitshousehold transmission, being most effective when the infected case in the household has a highviral burden. -
Date:17שלישידצמבר 2024הרצאה
Understanding drug resistance in leukaemia with computer simulations (and some experiments)
More information שעה 14:00 - 15:00מיקום Schmidt Auditoriumמרצה Prof. Ran Friedman מארגן המחלקה לביולוגיה מבנית וכימית -
Date:18רביעידצמבר 2024הרצאה
Special Guest Seminar
More information שעה 11:00 - 12:00כותרת Endocrine Cell Development in Human Fetal Thyroid Across Health and Diseaseמיקום בניין ע"ש מקס ולילאן קנדיוטימרצה Dr. Hassan Massalha
Wellcome Sanger Institute and University of Cambridge, UKמארגן המחלקה לאימונולוגיה ורגנרציה ביולוגיתצרו קשר -
Date:18רביעידצמבר 2024הרצאה
A Computational Perspective on Supercooled and Glassy Water
More information שעה 11:00 - 11:00מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Pablo G. Debenedetti מארגן מרכז לתיאוריה כימית וחישוביות על שם בן מיידף בית צרו קשר -
Date:18רביעידצמבר 2024הרצאה
זרקור מדעי
More information שעה 12:30 - 14:00מיקום אולם הרצאות ע"ש גרהרד שמידטצרו קשר -
Date:18רביעידצמבר 2024הרצאה
Why did the RNA Cross the (Nano) Road? To Get to the Other Side
More information שעה 12:30 - 14:00מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Dr. Gil Haimovich
Spotlight on Science lecture sponsored by the Staff Scientists Councilצרו קשר תקציר Show full text abstract about All cells communicate with their neighbors. One type of conn...» All cells communicate with their neighbors. One type of connection between animal cells is called Tunneling Nanotubes. These are open-ended natural tubes that allow cells to share small molecules, proteins, and even organelles.In the Gerst lab, we mostly study the transport of messenger-RNA molecules, which carry the information needed to produce proteins inside the cell. One amazing discovery that we made was finding out that mRNAs can also be transferred between cells through these nanotubes. We still don’t know exactly how or why. But we can use it!In this talk, I will describe the journey from the initial discovery to our plans to use it as a novel type of RNA therapeutic for rare genetic diseases. -
Date:18רביעידצמבר 2024הרצאה
ABC CHATS: Shira Eting
More information שעה 14:00 - 15:30כותרת Based on values, Delivering valueמיקום בניין על-שם גרשון ואסתר סאגאן
Bina Hub- loungeמרצה Shira Eting - Vintage Investment Partners צרו קשר תקציר Show full text abstract about During her conversation, Shira will share her personal journ...» During her conversation, Shira will share her personal journey and share what has led her to each decision and what are her key learnings.She will also share more about her position today as a Partner at Vintage, leading their investments in Healthcare and Climate.Join our ABC CHATS, Where CEOs share their ABC’s on scientific leadership, breakthroughs and failures throughout their personal stories -
Date:19חמישידצמבר 2024הרצאה
Geometric Functional Analysis and Probability Seminar
More information שעה 13:30 - 14:30כותרת Directional expansivity in ergodic Z^d systems and its applicationsמיקום בניין יעקב זיסקינד
Room 155 - חדר 155מרצה Sasha Fish
Sydneyמארגן המחלקה למתמטיקהצרו קשר תקציר Show full text abstract about By ergodicity, any set of positive measure is expanded to a ...» By ergodicity, any set of positive measure is expanded to a set of full measure under all translations in Z^d. But what happens if we restrict the translations to a specific line in Z^d? In this talk, we will explore this question and, using Furstenberg’s correspondence principle, demonstrate that the set of volumes of all simplices in Z^d formed by vertices of a positive-density set always contains an infinite arithmetic progression. This talk is based on joint works with M. Björklund (Chalmers) and S. Skinner (Sydney). -
Date:19חמישידצמבר 2024הרצאה
Reprogramming the Immune System: A New Avenue in Cancer Treatment
More information שעה 14:00 - 15:00מיקום בניין ע"ש מקס ולילאן קנדיוטימרצה Prof. Mira Barda-Saad
The Mina and Everard Goodman Faculty of Life Sciencesמארגן מרכז הבינתחומי לחקר סרטן עש מורוסצרו קשר -
Date:22ראשוןדצמבר 2024הרצאה
Multi-level ecosystem response to drying climate trends
More information שעה 11:00 - 12:00מיקום בניין משפחת זוסמן
M. Magaritz seminar roomמרצה Ehud Meron תקציר Show full text abstract about Climate change and the development of drier climates threate...» Climate change and the development of drier climates threatenecosystems’ health and the services they provide to humans.Understanding ecosystem response to drier climates may provide clueson improving their functioning and resilience. This response is likely toinvolve mechanisms operating at different levels of ecologicalorganization. At the single-plant level, phenotypic changes can occur; atthe population level, spatial patterns can form; and at the communitylevel, community reassembly and biodiversity changes can occur.These mechanisms must affect one another, as stress relaxation byone mechanism weakens the driving forces of other mechanisms, butcomplex ecosystem responses involving coupled mechanisms havehardly been studied. In this talk I will focus on the interplay betweenphenotypic changes and spatial patterning and between spatialpatterning and community reassembly. Using mathematical models ofwater-limited plant communities, I will show that incorporatingphenotypic plasticity into vegetation pattern-formation theory canresolve two outstanding puzzles associated with the fascinatingNamibian fairy circle phenomenon and describe a predicted bufferingeffect of spatial patterning on community composition along rainfallgradients. Possible implications of these results to ecosystemfunctioning in stressed environments will be discussed. -
Date:22ראשוןדצמבר 2024הרצאה
Making Climate Tech Work – Policies that Drive Innovation
More information שעה 13:00 - 14:00מיקום בניין לביוכימיה על שם נלה וליאון בנוזיו למדעי הצמח
690מרצה Prof. Alon Tal
Host: Prof. Ron Milo, IES Directorמארגן המכון לסביבה וקיימות , ממונה על היוזמה לחקר האנרגיה והקיימותצרו קשר -
Date:22ראשוןדצמבר 2024הרצאה
The Clore Center for Biological Physics
More information שעה 13:15 - 14:30כותרת The harmonic three-body problem: from gauge field theory of falling cats to fractional rotational diffusionמיקום ספרית הפיסיקה על שם נלה וליאון בנוזיומרצה Prof. Efi Efrati
lunch will be served at 12:45מארגן מרכז לפיזיקה ביולוגית עש קלורצרו קשר תקציר Show full text abstract about In this talk I will present the study of the non-h...» In this talk I will present the study of the non-holonomic rotational dynamics of the classical harmonic three mass system in the strongly nonlinear regime. This is the simplest isolated spring-mass system capable of displaying rotation with zero angular momentum as well as chaotic dynamics. Combined together these two phenomena lead to a wide variety of qualitatively distinct dynamical phases as a function of the system's internal energy. For low energy, where dynamics are regular, we observe a constant rotation rate with zero angular momentum. For sufficiently high energy we observe a rotational random walk driven by the system's internal chaotic dynamics. For intermediate energies, we observe ballistic bouts of constant rotation rates interrupted by unpredictable orientation reversal events. In this regime, the system constitutes a simple physical model for Levy walks and the orientation reversal statistics lead to fractional rotational diffusion interpolating smoothly between the ballistic and regular diffusive regimes. FOR THE LATEST UPDATES AND CONTENT ON SOFT MATTER AND BIOLOGICAL PHYSICS AT THE WEIZMANN, VISIT OUR WEBSITE: https://www.biosoftweizmann.com/ -
Date:23שנידצמבר 2024הרצאה
The Israel Rubinstein 4th Memorial Lecture -"The challenge of rechargeable batteries with very high energy density and prolonged cycle life: from basic science to practical devices"
More information שעה 11:00 - 12:00מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Doron Aurbach
Bar Ilan University, Department of Chemistryמארגן המחלקה לכימיה מולקולרית ולמדע חומריםצרו קשר תקציר Show full text abstract about The development of high energy density, long running recharg...» The development of high energy density, long running rechargeable batteries like
Li ion batteries, that power so successfully all mobile electronic devices, can be
considered as the greatest success of modern electrochemistry.
However, the basis for this success was the capability of exploring most complex
electrodes, electrolyte solutions and reactive interfaces by most sophisticated
electroanalytical tools in conjunction with advanced spectroscopic and microscopic
was a first-rate leader in electroanalytical ז"ל techniques. Professor Israel Rubinstein
chemistry. I learned a lot from him.
The main theme of this presentation is to examine what is the true horizons for advanced
high energy density batteries that can promote the electro-mobility revolution. The
limiting factor in Li-ion batteries in terms of energy density, cost, potential, durability
and cycling efficiency are the cathode materials used. We will examine most energetic
cathode materials and novel approaches we developed for their stabilization. We
describe in this lecture which electrode materials can be relevant, methodologies
of their stabilization by doping, coating, and affecting electrodes surface chemistry
by the use of active additives. Most important cathode materials are comprising the
5 elements Li,Ni,Co,Mn,O at different stoichiometries that determine voltage and
specific capacities. We will explain how the stoichiometry dictates basic cathodes
properties.1,2 We will discuss the renaissance of Li metal-based rechargeable batteries.3
We have learned how the stabilize Li metal anodes in rechargeable batteries using
reactive electrolyte solutions that induce excellent passivation through controlled
surface reactions. The emphasis is on fluorinated co-solvents that open the door for a
very rich surface chemistry that forms passivating surface films that behave as ideal
solid electrolyte interphase on both anodes and cathodes in advanced secondary Li
batteries. This field provides fascinating examples how systematic basic scientific
work leads to development of most practical devices for energy storage & conversion. -
Date:23שנידצמבר 2024הרצאה
Foundations of Computer Science Seminar
More information שעה 11:15 - 12:15כותרת On Cryptography and the Perebor Conjecturesמיקום בניין יעקב זיסקינד
Room 1 - 1 חדרמרצה Noam Mazor
Tel Aviv Universityמארגן המחלקה למדעי המחשב ומתמטיקה שימושיתצרו קשר תקציר Show full text abstract about The Perebor (Russian for "brute-force search") con...» The Perebor (Russian for "brute-force search") conjectures are among the oldest conjectures in complexity theory. These conjectures, a stronger form of the P!=NP conjecture (which they predate), assert that for "meta-complexity" problems—such as the Time-Bounded Kolmogorov Complexity Problem and the Minimum Circuit Size Problem (MCSP)—no algorithms significantly outperform brute-force search.
In this talk, we will refute the non-uniform version of the Perebor conjecture for the Time-Bounded Kolmogorov Complexity Problem. Specifically, for every polynomial t(.), we will see a circuit of size 2^{4n/5+o(n)} that solves the t(.)-bounded Kolmogorov complexity problem on all instances. Along the way, and of independent interest, we will extend the Fiat-Naor result, by showing that any efficiently computable function can be inverted by a circuit of size 2^{4n/5+o(n)}.
Furthermore, we will show that, under cryptographic assumptions, Gap versions of meta-complexity problems are not NP-complete under Levin (witness-preserving) reductions. Finally, we will demonstrate how this barrier, combined with known NP-completeness results for meta-complexity problems, leads to a lower bound on the overhead of indistinguishability obfuscation (iO).
This talk is based on joint works with Zhenjian Lu, Igor C. Oliveira, and Rafael Pass. -
Date:24שלישידצמבר 2024הרצאה
Winter STAR Workshop
More information שעה 10:00 - 18:00מיקום בניין יעקב זיסקינד
1 & 155 -
Date:24שלישידצמבר 2024הרצאה
Anterior-Posterior Insula Circuit Mediates Retrieval of a Conditioned Immune Response in Mice
More information שעה 12:30 - 13:30מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Kobi Rosenblum מארגן המחלקה למדעי המוחצרו קשר תקציר Show full text abstract about The brain can form associations between sensory information ...» The brain can form associations between sensory information of inner and/or outer world (e.g. Pavlovian conditioning) but also between sensory information and the immune system. The phenomenon which was described in the last century is termed conditioned immune response (CIR) but very little is known about neuronal mechanisms subserving it. The conditioned stimulus can be a given taste and the unconditioned stimulus is an agent that induces or reduces a specific immune response. Over the last years, we and others revealed molecular and cellular mechanisms underlying taste valance representation in the anterior insular cortex (aIC). Recently, a circuit in the posterior insular cortex (pIC) encoding the internal representation of a given immune response was identified. Together, it allowed us to hypothesize and prove that the internal reciprocal connections between the anterior and posterior insula encode CIR. One can look at CIR as a noon declarative form of Nocebo effect and thus we demonstrate for the first time a detailed circuit mechanism for Placebo/Nocebo effect in the cortex. -
Date:25רביעידצמבר 2024הרצאה
Winter STAR Workshop
More information שעה 10:00 - 18:00מיקום בניין יעקב זיסקינד
1 & 155 -
Date:25רביעידצמבר 2024הרצאה
Machine Learning and Statistics Seminar
More information שעה 11:15 - 12:15כותרת Communal AI - Open, Collaborative & Accessible LLMsמיקום בניין יעקב זיסקינד
Room 1 - 1 חדרמרצה Leshem Choshen
MITמארגן המחלקה למדעי המחשב ומתמטיקה שימושיתצרו קשר תקציר Show full text abstract about Developing better Language Models would benefit a myriad of ...» Developing better Language Models would benefit a myriad of communities. However, it is prohibitively costly. The talk would describe collaborative approaches to pretraining, such as model merging, which allows the combining of several specialized models into one. Then, it would introduce efficient evaluation to reduce overheads and touch on other accessible and collaborative aspects that best harness the expertise and diversity in Academia.