Pages
October 05, 2015
-
Date:05MondayMay 2025Lecture
conference on Representation Theory and Algebraic Geometry in honor of Joseph Bernstein on the occasion of his 80th birthday
More information Time All dayLocation The David Lopatie Conference Centre -
Date:05MondayMay 2025Colloquia
The Shaping and Unshaping of DNA
More information Time 11:00 - 12:15Location Gerhard M.J. Schmidt Lecture HallLecturer Prof. Erez S. Lieberman Aiden Homepage Abstract Show full text abstract about Stretched out from end-to-end, the human genome is a two met...» Stretched out from end-to-end, the human genome is a two meter long polymer chain. But this one-dimensional polymer is arranged inside a three-dimensional nucleus, so that genomic elements far apart along DNA can come into close spatial proximity. This interplay between linear genomic space, in which the heteropolymer’s complex monomer sequence is arrayed, and three-dimensional nuclear space, where the polymer actively interacts with its environment, gives rise to the genome’s 3D architecture. It has long been known that this architecture has the potential to regulate gene activity and drive cellular identity and function. Yet for decades, the principles governing the genome's shape were largely unknown. My research has focused on deciphering these principles—developing technologies to map the genome’s 3D structure and using the resulting maps to discover fundamental folding mechanisms in living cells. We and our collaborators have shown that the polymer chain adopts conformations at multiple scales: simple physical constraints at large scales, domain formation and compartmentalization at intermediate scales, and highly regulated, non-equilibrium loop extrusion events at fine scales.I will also show how we've applied these methods to accelerate genome sequencing, enabling us to study the evolution of chromosome architecture across the tree of life. This has led to the discovery of chromosome (sub)fossils in the remains of extinct creatures, and revealed how the DNA in these fossils gradually loses its shape over deep time. -
Date:05MondayMay 2025Lecture
Foundations of Computer Science Seminar
More information Time 11:15 - 12:15Title Approximate counting of permutation patternsLocation Jacob Ziskind Building
Room 1 - 1 חדרLecturer Omri Ben-Eliezer
TechnionOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about A copy of a permutation pattern (say, 132) in a sequence of ...» A copy of a permutation pattern (say, 132) in a sequence of numbers is any subsequence whose values have the same relative order as in the pattern. (Say, for 132, the first element is smallest, the second is largest, and the third is in-between.)
Counting permutation patterns has a surprisingly rich set of connections and applications in ranking, statistics, combinatorics, fine-grained complexity, and parametrized complexity, especially for fixed small k. Here are three examples:
(i) Counting 4-cycles in sparse graphs is equivalent to counting 4-patterns [Dudek and Gawrychowski, 2020].
(ii) Many fundamental tests in nonparametric statistics amount to counting k-patterns for k up to 5.
(iii) The study of twin-width in parametrized complexity has originated from a breakthrough FPT algorithm of Guillemot and Marx [2013] for permutation pattern detection, which runs in linear time when k is fixed.
In this talk I will describe an algorithm for approximately counting all k-patterns for k up to 5 in near-linear time, deterministically, to within a (1+eps)-multiplicative error. This algorithm gives the first known (conditional) separation between exact and approximate counting in this domain. Interestingly, our algorithm leverages sublinear techniques from distribution testing, which to our knowledge have not been used in a pattern counting context before.
Joint work with Slobodan Mitrović (UC Davis) and Pranjal Srivastava (MIT) -
Date:05MondayMay 2025Lecture
Midrasha on Groups Seminar
More information Time 11:15 - 13:00Title The representation theory of PGL2Location Elaine and Bram Goldsmith Building for Mathematics and Computer Sciences
Room 208 - חדר 208Lecturer Assaf Reiner
HUJIOrganizer Department of MathematicsContact Abstract Show full text abstract about I will give an introduction to the representation theory of ...» I will give an introduction to the representation theory of PGL2 over the reals and the p-adics, using a unified treatment of both cases, and connect it with the eigenvalues of
the corresponding Laplacians. I will also present the tree associated with PGL2(Qp) analogous to the hyperbolic upper half-plane associated with PGL2(R). I will mainly follow pages 61–70 of [Lub]. -
Date:05MondayMay 2025Lecture
Midrasha on Groups Seminar
More information Time 14:15 - 16:00Title Measure equivalence rigidity via groupoidsLocation Elaine and Bram Goldsmith Building for Mathematics and Computer Sciences
Room 208 - חדר 208Lecturer Corentin Le Bars
WeizmannOrganizer Department of MathematicsContact Abstract Show full text abstract about A central question in measured group theory is to classify g...» A central question in measured group theory is to classify groups up to measure equivalence. In this talk, I will present an approach to measure equivalence rigidity involving the language of groupoids. This approach was introduced by Kida for mapping class groups of surfaces, building on earlier works of, notably, Furman and its seminal result on orbit equivalence rigidity for lattices in higher rank simple Lie groups. If time allows it, I will mention an ongoing project with A. Derimay and S. Gurieva aiming at studying rigidity properties of products of such lattices, a case not covered by the celebrated Monod-Shalom paper for products of negatively curved groups. -
Date:06TuesdayMay 2025Lecture
conference on Representation Theory and Algebraic Geometry in honor of Joseph Bernstein on the occasion of his 80th birthday
More information Time All dayLocation The David Lopatie Conference Centre -
Date:06TuesdayMay 2025Lecture
The evolution of host-virus interactions: Lessons from viral mimicry
More information Time 14:00 - 15:00Location Gerhard M.J. Schmidt Lecture HallLecturer Dr. Tzachi Hagai Organizer Department of Chemical and Structural BiologyAbstract Show full text abstract about Evolutionary changes in the host-virus interactome can alter...» Evolutionary changes in the host-virus interactome can alter the course of infection, but which and how often interactions evolve and how this is realized at the interface residue level, remain largely unexplored. Here, we focus on viral mimicry of motifs and domains of host proteins, that allow efficient binding to host proteins by mimicking interfaces of host proteins. Our results show that in contrast to the prevailing view of rapid interface evolution between host- and viral-interacting proteins, viruses evolved to target highly conserved host proteins. The similarity between viral mimics and their host mimicked proteins limits host capacity to escape interaction with mimics, enabling efficient viral interaction with host targets through mimicry. These results have important implications for our understanding of zoonotic events where novel host-virus protein interactions may evolve and for designing new antiviral drugs targeting interface regions between host and viral proteins. -
Date:07WednesdayMay 2025Lecture
students seminar series- Azrieli
More information Time 10:30 - 12:30Location Camelia Botnar BuildingContact -
Date:08ThursdayMay 2025Lecture
Recent advances in Flow Cytometry – from nano-particles to whole organisms
More information Time 09:00 - 10:00Location Candiotty AuditoriumLecturer Dr. Ziv Porat Organizer Department of Life Sciences Core FacilitiesContact -
Date:08ThursdayMay 2025Colloquia
Dark Matter snooker (Dark matter via multiple collisions)
More information Time 11:15 - 12:30Location Physics Weissman AuditoriumLecturer Prof. Maxim Pospelov
The University of MinnesotaOrganizer Department of Physics of Complex SystemsContact Abstract Show full text abstract about Despite enormous experimental investment in searches of part...» Despite enormous experimental investment in searches of particle darkmatter, certain well-motivated corners of parameter space remain to beelusive "blind spots" for direct detection. In my talk I will address two ofsuch exceptions: light particles that simply do not have enough kineticenergy to detect, and strongly-interacting particles that quickly thermalizeand also become sub-threshold for direct detection. I show that both blindspots can be probed through double collisions of Dark matter -- first withsome energetic Standard model particles (solar electrons, cosmic rays,particles in a beam, neutrons in nuclear reactors etc) that bring DM toenergies above thresholds followed by the scattering inside a detector. Thisway, I derive novel constraints on light dark matter, as well as stronglyinteractingdark matter models, using existing dark matter and neutrinoexperiments. -
Date:08ThursdayMay 2025Lecture
Vision and AI
More information Time 12:15 - 13:15Title Image Restoration and Compression with Generative Models: Theory and PracticeLocation Jacob Ziskind Building
Room 1 - 1 חדרLecturer Guy Ohayon
TechnionOrganizer Department of Computer Science and Applied MathematicsContact Abstract Show full text abstract about In this seminar, I will discuss several fundamental challeng...» In this seminar, I will discuss several fundamental challenges and limitations associated with high-perceptual-quality image restoration methods, and propose practical restoration and compression schemes. Specifically, I will first examine deterministic image restoration algorithms and show why striving for high output quality while maintaining consistency with the input measurements inevitably leads to algorithmic instability and vulnerability to adversarial attacks. Secondly, since the perceptual quality and distortion of the reconstructions are typically at odds with each other, a key challenge in image restoration is to minimize the distortion under a constraint of perfect output quality. To address this optimization problem, I will introduce a novel algorithm that leverages a rectified flow model to approximate the optimal solution. Finally, I will present an innovative generative approach based on pre-trained diffusion models, which produces high-quality image samples along with their losslessly compressed bit-stream representations. This new generative framework seamlessly extends to a variety of tasks, including image compression, compressed image restoration, compressed image editing, and more generally, any compressed conditional generation task.
Bio:
Guy Ohayon holds a BSc in Computer Engineering from the Technion (2021) and is in the final stages of his PhD, working under the supervision of Prof. Michael Elad and Prof. Tomer Michaeli. His doctoral research focuses on the theory and practice of image restoration and compression using generative models. Guy will soon begin a postdoctoral fellowship at the Flatiron Institute (Simons Foundation) in New York City, where he will work with Prof. Eero Simoncelli. -
Date:08ThursdayMay 2025Academic Events
Career Fair
More information Time 12:45 - 18:00Title Shaping Israel’s Future through Science and InnovationLocation David Lopatie Conference CentreHomepage Contact -
Date:08ThursdayMay 2025Lecture
Geometric Functional Analysis and Probability Seminar
More information Time 13:30 - 14:30Title Gaussian Free Field on the Tree Subject to a Hard WallLocation Jacob Ziskind Building
Room 155 - חדר 155Lecturer Oren Louidor
TechnionOrganizer Department of MathematicsContact Abstract Show full text abstract about We study the discrete Gaussian free field on the binary tree...» We study the discrete Gaussian free field on the binary tree when all leaves are conditioned to be positive. We obtain sharp asymptotics for the probability of this ``hard-wall constraint'' event, and identify the repulsion profile followed by the field in order to achieve it. We then provide estimates for the mean, fluctuations and covariances of the field under the conditioning, which show that in the first log-many generations the field is super-exponentially tight around its mean. These results are then used to obtain a comprehensive, sharp asymptotic description of the law of the field under this conditioning. We provide asymptotics for both local statistics, namely the (conditional) law of the field in a neighborhood of a vertex, as well as global statistics, including the (conditional) law of the minimum, maximum, empirical population mean and all subcritical exponential martingales. We conclude that, even in a local sense, the recentered repelled field is asymptotically not the unconditional field, thereby resolving an open question of Velenik from 2006, albeit in the analogous case of the tree.
Joint work with Maximilian Fels (Technion) and Lisa Hartung (Mainz). -
Date:08ThursdayMay 2025Lecture
EARLY-ONSET GI CANCER – AN EVOLVING ENTITY
More information Time 14:00 - 15:00Location Max and Lillian Candiotty Building
AuditoriumLecturer Prof. Irit Ben-Aharon MD, PhD Organizer Dwek Institute for Cancer Therapy Research -
Date:11SundayMay 2025Conference
Early Cancer Detection and Precision Prevention
More information Time 08:00 - 08:00Title Early Cancer Detection and Precision PreventionLocation The David Lopatie Conference CentreChairperson Sima LevOrganizer Swiss Society Institute for Cancer Prevention Research , Moross Integrated Cancer Center (MICC)Contact -
Date:11SundayMay 2025Lecture
The Clore Center for Biological Physics
More information Time 13:15 - 14:30Title Second law of Thermodynamics in Living MatterLocation Koffler Accelerator of the Canada Center of Nuclear PhysicsLecturer Dr. Tomer Markovich
Lunch will be served at 12:45Contact Abstract Show full text abstract about Materials that are constantly driven out of thermodynamic eq...» Materials that are constantly driven out of thermodynamic equilibrium, such as active and living systems, typically violate the Einstein relation. This may arise from active contributions to particle fluctuations which are unrelated to the dissipative resistance of the surrounding medium. In this talk I will show that in these cases the widely used relation between informatic entropy production and heat dissipation does not hold. Consequently, fluctuation relations for the mechanical work, such as the Jarzynski and Crooks theorems, are invalid. The breaking of the correspondence between informatic entropy production and heat dissipation will then be related to the departure from the fluctuation-dissipation theorem. I will finally propose a temperaturelike variable that restores the correspondence between information and thermodynamics and gives rise to a generalized second law of thermodynamics. The Clausius inequality, Carnot maximum efficiency theorem, and relation between the extractable work and the change of free energy are recovered as well. -
Date:11SundayMay 2025Cultural Events
Blow the Trumpet | The Israel Camerata Jerusalem
More information Time 20:00 - 21:30Location Michael Sela AuditoriumHomepage Contact -
Date:12MondayMay 2025Academic Events
Seminar for PhD thesis defense
More information Time 14:00 - 15:00Title TDP-43 pathology in ALS: from organelles to splicing, and an unexpected link to Alzheimer's DiseaseLocation Arthur and Rochelle Belfer Building for Biomedical Research
Botnar AuditoriumLecturer Joelle Welmoed Rachel Van Zuiden -
Date:12MondayMay 2025Academic Events
David Lerner, PhD. Defense Seminar
More information Time 16:00 - 17:00Title The evolution and distribution of tree species across the latitudinal axis - From a global to a regional scaleLocation Nella and Leon Benoziyo Building for Plant and Environmental Sciences
690Lecturer David Lerner
Department of Plant and Environmental SciencesContact -
Date:14WednesdayMay 2025Lecture
Development as a Metabolic Regulator: How Molting Controls Cholesteryl Ester Metabolism in the Somatic Stem Cells of C. elegans
More information Time 10:00 - 11:00Location Arthur and Rochelle Belfer Building for Biomedical Research
Botnar AuditoriumLecturer Dr. Amir Sapir Contact Abstract Show full text abstract about Development as a Metabolic Regulator: How Molting Controls C...» Development as a Metabolic Regulator: How Molting Controls Cholesteryl Ester Metabolism in the Somatic Stem Cells of C. elegans Raj Rani1, Or Ben-Hemo1, Benjamin Trabelcy1, Agam Bar1, Hans-Joachim Knölker2, Yoram Gerchman1,3,4, and Amir Sapir1*1Department of Biology and the Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon, 36006 Israel2 Fakultät Chemie, Technische Universität Dresden, Bergstrasse 66, 01069 Dresden, Germany3Institute of Evolution, Faculty of Natural Sciences, University of Haifa, Haifa, Israel4Oranim Academic College, Kiryat Tivon, Israel The metabolism of steroids, such as cholesterol, is critical for mammalian physiology and human health, yet its function in invertebrates remains poorly understood. Using Caenorhabditis elegans, we constructed the first comprehensive homology-based enzymatic atlas of steroid metabolism in invertebrates, identifying 159 candidate genes. We performed a two-dimensional genetic and metabolic screen, knocking down the atlas genes under varying cholesterol conditions to identify those functioning in steroid metabolism. Among the screen hits, we focused on mboa-1, an ortholog of mammalian SOAT1/2 enzymes that synthesize cholesteryl esters from sterols and fatty acids. Surprisingly, mboa-1 knockdown and knockout disrupt hypodermis and cuticle integrity. Consistent with its predicted enzymatic function, bacterially expressed C. elegans MBOA-1 generates cholesteryl esters when supplemented with the steroid 4,3-cholesta and fatty acids. Moreover, 4,3-cholesta—but not steroid hormones—rescued the mboa-1 RNAi phenotype, suggesting a new branch of steroid metabolism in C. elegans. mboa-1 is expressed specifically in the somatic stem cells of C. elegans, the seam cells, which contribute to the hypodermis and cuticle. Expression begins in mid-embryogenesis, persists throughout larval development, but declines sharply in adults. Underscoring its role in cuticle dynamics, mboa-1 expression oscillates with the molting cycle and is regulated by lin-29–mediated heterochronic control during the larval-to-adult transition, a stage when seam cells terminally differentiate. Our functional studies in Clade IV and V nematodes, along with insect expression data, suggest that during evolution, mboa-1 regulation was rewired to support a structural role for cholesteryl esters in cuticle formation, diverging from their primarily metabolic functions in mammals and insects. Our findings reveal how, during evolution, steroid metabolism was repurposed for a novel function in nematodes through the mechanistic reconfiguring of developmental regulation and stem cell biology.