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January 01, 2013
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Date:23MondayDecember 2024Lecture
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 Time 11:00 - 12:00Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Doron Aurbach
Bar Ilan University, Department of ChemistryOrganizer Department of Molecular Chemistry and Materials ScienceContact Abstract 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:23MondayDecember 2024Lecture
Foundations of Computer Science Seminar
More information Time 11:15 - 12:15Title On Cryptography and the Perebor ConjecturesLocation Jacob Ziskind Building
Room 1 - 1 חדרLecturer Noam Mazor
Tel Aviv UniversityOrganizer Department of Computer Science and Applied MathematicsContact Abstract 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:24TuesdayDecember 2024Lecture
Winter STAR Workshop
More information Time 10:00 - 18:00Location Jacob Ziskind Building
1 & 155 -
Date:24TuesdayDecember 2024Lecture
Anterior-Posterior Insula Circuit Mediates Retrieval of a Conditioned Immune Response in Mice
More information Time 12:30 - 13:30Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Kobi Rosenblum Organizer Department of Brain SciencesContact Abstract 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:25WednesdayDecember 2024Lecture
Winter STAR Workshop
More information Time 10:00 - 18:00Location Jacob Ziskind Building
1 & 155 -
Date:25WednesdayDecember 2024Lecture
Machine Learning and Statistics Seminar
More information Time 11:15 - 12:15Title Communal AI - Open, Collaborative & Accessible LLMsLocation Jacob Ziskind Building
Room 1 - 1 חדרLecturer Leshem Choshen
MITOrganizer Department of Computer Science and Applied MathematicsContact Abstract 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. -
Date:26ThursdayDecember 2024Cultural Events
An intimate meeting with the families of the hostages Tal Shoham and Yagev Buchshtab
More information Time 09:45 - 11:15Location Nella and Leon Benoziyo Building for Biological Sciences
AuditoriumOrganizer Department of Molecular Cell BiologyContact -
Date:26ThursdayDecember 2024Lecture
Winter STAR Workshop
More information Time 10:00 - 18:00Location Jacob Ziskind Building
1 & 155 -
Date:26ThursdayDecember 2024Lecture
Foundations of Computer Science Seminar
More information Time 10:15 - 11:45Title Algorithmic Contract DesignLocation Jacob Ziskind BuildingLecturer Tomer Ezra
HarvardOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about We explore the framework of contract design through a comput...» We explore the framework of contract design through a computational perspective. Contract design is a fundamental pillar of microeconomics, addressing the essential question of how to incentivize people to work. The significance of contract design was acknowledged by the Nobel Prize awarded to Hart and Holmström, and it applies to various real-life scenarios, such as determining bonuses for employees, setting commission structures for sales representatives, and designing payment schemes for influencers promoting products.
While contract design has been extensively studied from an economic perspective, this talk will examine it from a computational viewpoint. Specifically, we introduce combinatorial extensions of classic contract design models, where a principal delegates tasks to one or multiple agents. The agents have sets of potential actions they can take to complete the task, and the chosen actions by the agents stochastically determine the success of the task. We analyze the structure and computational aspects of these models, and present algorithms that provide (approximately) optimal guarantees. -
Date:26ThursdayDecember 2024Lecture
Vision and AI
More information Time 12:15 - 13:15Title Discovering and Erasing Undesired ConceptsLocation Jacob Ziskind BuildingLecturer Niv Cohen
NYUOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about The rapid growth of generative models allows an ever-increas...» The rapid growth of generative models allows an ever-increasing variety of capabilities. Yet, these models may also produce undesired content such as unsafe images, private information, or copyrighted material.
In this talk, I will discuss practical methods to prevent undesired generations. First, I will show how the challenge of avoiding undesired generations manifested itself in a simple Capture-the-Flag LLM setting, where even our top defense strategy was breached. Next, I will demonstrate a similar vulnerability in state-of-the-art concept erasure methods for Text-to-Image models. Finally, I will describe the notion of ‘Unconditional Concept Erasure’ aiming to mitigate such vulnerabilities. I will show that Task Vectors can achieve Unconditional Concept Erasure, and discuss the challenge of applying Task Vectors in practice.
Bio: Niv is a postdoctoral researcher at New York University hosted by Prof. Chinmay Hegde. He received a BSc in mathematics with physics as part of the Technion Excellence Program. He received his PhD in computer science from the Hebrew University of Jerusalem, advised by Prof. Yedid Hoshen. Niv was awarded the Israeli data science scholarship for outstanding postdoctoral fellows (VATAT). He is interested in anomaly detection, model personalization, and AI safety for Vision -
Date:26ThursdayDecember 2024Lecture
Deep language models as a cognitive model for natural language processing in the human brain
More information Time 12:30 - 13:30Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Uri Hasson
Special SeminarOrganizer Department of Brain SciencesContact Abstract Show full text abstract about Naturalistic experimental paradigms in cognitive neuroscienc...» Naturalistic experimental paradigms in cognitive neuroscience arose from a pressure to test, in real-world contexts, the validity of models we derive from highly controlled laboratory experiments. In many cases, however, such efforts led to the realization that models (i.e., explanatory principles) developed under particular experimental manipulations fail to capture many aspects of reality (variance) in the real world. Recent advances in artificial neural networks provide an alternative computational framework for modeling cognition in natural contexts. In this talk, I will ask whether the human brain's underlying computations are similar or different from the underlying computations in deep neural networks, focusing on the underlying neural process that supports natural language processing in adults and language development in children. I will provide evidence for some shared computational principles between deep language models and the neural code for natural language processing in the human brain. This indicates that, to some extent, the brain relies on overparameterized optimization methods to comprehend and produce language. At the same time, I will present evidence that the brain differs from deep language models as speakers try to convey new ideas and thoughts. Finally, I will discuss our ongoing attempt to use deep acoustic-to-speech-to-language models to model language acquisition in children. -
Date:26ThursdayDecember 2024Lecture
Exploring the role of pipecolic acid in Plasmodium falciparumnnounced
More information Time 15:00 - 16:00Location Nella and Leon Benoziyo Building for Biological Sciences
Cafeteria, floor 0Lecturer Sonia Oren Organizer Department of Biomolecular SciencesContact Abstract Show full text abstract about Plasmodium falciparum (Pf) parasite is the major ca...» Plasmodium falciparum (Pf) parasite is the major cause of malaria disease, resulting in more than 600,000 deaths annually. Patients with cerebral malaria, the most severe form of malaria, show elevated plasma L-pipecolic acid (PA) concentrations in their blood compared to those with mild malaria. However, the origin and function of PA in Pf infection remain mostly elusive. Here, using LC/MS targeted metabolomics we found that the malaria parasite, while growing inside its host human Red Blood Cell (RBC), secretes PA during a specific life stage, the trophozoite. We then demonstrated that pretreatment of the host naïve human RBCs with PA significantly enhances parasitic growth. To further investigate the effect of PA on its primary host, RBCs, we measured the biophysical alterations in the pretreated naïve RBCs using atomic force microscopy combined with machine learning. Surprisingly, we found that PA modifies the mechanical properties of the host cell’s membrane, turning it significantly softer. Electron paramagnetic resonance data on liposomes suggest that PA’s mechanism may involve altering the lipid mobility. Overall, our findings reveal that the parasite secretes PA to prime its host RBCs for invasion by inducing mechanical changes in the stiffness of the host membrane. These results indicate that PA functions as an active secreted metabolite, facilitating Pf growth within its host cell. -
Date:29SundayDecember 2024Lecture
Atmospheric stability sets extreme surface moist heat
More information Time 11:00 - 12:00Location Sussman Family Building for Environmental Sciences
M. Magaritz seminar roomLecturer Talia Tamarin-Brodsky Contact Abstract Show full text abstract about Heatwaves have been extensively studied in the past, primari...» Heatwaves have been extensively studied in the past, primarily from the standpoint of heatwave formation.Previous studies have identified air subsidence, diabatic heating, and warm air advection as the primary mechanisms for heat accumulation at the surface. However, less workhas focused on what leads to eatwave termination. A recent study suggests that surface temperature can onlyincrease until convection is triggered, and thus proposed a theoretical upper bound of maximum surface airtemperature, assuming a neutrally buoyant atmosphere and a dry surface. Given that most midlatitude heatwave events involve moist surface conditions, which also support theaccumulation of Convective Available Potential Energy (CAPE), we propose an alternative theory that quantifieschanges in surface moist temperature while correctly accounting for the buildup of CAPE. We show that the lower free tropospheric inversion predicts the maximum intensity ofboth moist heat and moist convection in midlatitudes. Implications for heatwave evolution and projected future changes in extreme moist heat events are discussed. -
Date:29SundayDecember 2024Lecture
Perceptual decision coding is inherently coupled to action in the mouse cortex
More information Time 12:00 - 13:15Location Max and Lillian Candiotty Building
AuditoriumLecturer Michael Sokoletsky PhD Defense
Student Seminar-PhD Thesis DefenseOrganizer Department of Brain SciencesContact Abstract Show full text abstract about How do animals make perceptual decisions about sensory stimu...» How do animals make perceptual decisions about sensory stimuli to guide motor actions? One hypothesis is that dedicated "perceptual decision" cells process sensory information and drive the appropriate action. Alternatively, perceptual decisions result from competition among cells driving different actions, making decisions inherently coupled to actions. To distinguish between these hypotheses, we designed a vibrotactile detection task in which mice flexibly switched between standard and reversed contingency blocks, respectively requiring them to lick after stimulus presence or absence. Optogenetic inactivation of somatosensory and secondary motor cortices reduced stimulus sensitivity without impairing the ability to lick. However, widefield and two-photon imaging found that differences in cortical activity across perceptual decisions were almost exclusively action-coupled. In addition, we identified a subset of cells that encoded the current contingency block in a gated manner, enabling mice to flexibly make decisions without relying on action-independent decision coding. -
Date:30MondayDecember 2024Lecture
Hierarchical Design Principles for Multifunctional Biocomposites
More information Time 10:00 - 11:00Location Schmidt Lecture HallLecturer Dr. Israel Kellersztein -
Date:30MondayDecember 2024Lecture
Foundations of Computer Science Seminar
More information Time 11:15 - 12:15Title Can We Bypass the Curse of Dimensionality in Private Data Analysis?Location Jacob Ziskind Building
Room 1 - 1 חדרLecturer Eliad Tsfadia
Georgetown UniversityOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about Differentially private (DP) algorithms typically exhibit a s...» Differentially private (DP) algorithms typically exhibit a significant dependence on the dimensionality of their input, as their error or sample complexity tends to grow polynomially with the dimension. This cost of dimensionality is inherent in many problems, as Bun, Ullman, and Vadhan (STOC 2014) showed that any method that achieves lower error rates is vulnerable to tracing attacks (also known as membership inference attacks). Unfortunately, such costs are often too high in many real-world scenarios, such as training large neural networks, where the number of parameters (the ambient dimension) is very high.
On the positive side, the lower bounds do not rule out the possibility of reducing error rates for "easy" inputs. But what constitutes "easy" inputs? And how likely is it to encounter such inputs in real-world scenarios?
In this talk, I will present a few ways to quantify "input easiness" for the fundamental task of private averaging and support them with upper and lower bounds. In particular, I will show types of properties that are both sufficient and necessary for eliminating the polynomial dependency on the dimension.
I will conclude by outlining future research directions and providing a broader perspective on my work.
The talk is mainly based on the following three papers:
(1) FriendlyCore https://arxiv.org/abs/2110.10132 (joint with Edith Cohen, Haim Kaplan, Yishay Mansour, and Uri Stemmer, ICML 2022),
(2) https://arxiv.org/abs/2307.07604 (joint with Naty Peter and Jonathan Ullman, COLT 2024),
(3) https://arxiv.org/abs/2402.06465 (NeurIPS 2024) -
Date:31TuesdayDecember 2024Lecture
Special Guest Seminar, Dr. Neta Gazit Shimoni
More information Time 10:00 - 11:00Title Molecular and Cell Biology, University of California at BerkeleyLocation Belfer Building, Botnar AuditoriumLecturer “Neuropeptides as Modulators of Synaptic Function and Behavior in Rodents” -
Date:31TuesdayDecember 2024Lecture
The Neural Basis of Affective States
More information Time 12:30 - 14:00Location Gerhard M.J. Schmidt Lecture HallLecturer Dr. Amit Vinograd Organizer Department of Brain SciencesContact Abstract Show full text abstract about How does the brain regulate innate behaviors and emotional s...» How does the brain regulate innate behaviors and emotional states? My researchis driven by a vision to decode evolutionarily conserved neural circuits that regulateaffective states like aggression and anxiety. In my work, I combine deep-brain 2-photoncalcium imaging and holographic optogenetics with theoretical neuroscience approachesto unravel latent manifolds of neural activity and their dynamics. One such dynamic, lineattractors, is hypothesized to encode continuous variables such as eye position, workingmemory, and internal states. However, direct evidence of neural implementation of a lineattractor in mammals has been hindered by the challenge of targeting perturbations tospecific neurons within ensembles. In this talk, I will present our recent breakthroughsdemonstrating causal evidence for line attractor dynamics in neurons encoding anaggressive state and highlight functional connectivity within specific neuronalensembles. This work effectively bridges circuit and manifold levels, providing strongevidence of intrinsic continuous attractor dynamics in a behaviorally relevant mammaliansystem. -
Date:31TuesdayDecember 2024Lecture
Go with the flow: energetic robustness in bacterial photosynthesis
More information Time 14:00 - 15:00Location Gerhard M.J. Schmidt Lecture HallLecturer Asst. Prof. Dvir Harris Organizer Department of Chemical and Structural Biology -
Date:01WednesdayJanuary 2025Lecture
students seminar series- Azrieli
More information Time 10:30 - 12:30Location Camelia Botnar BuildingContact