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  • Date:27WednesdayOctober 2021

    Algebraic Geometry and Representation Theory Seminar

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    Time
    15:00 - 16:00
    Title
    On the socles of certain parabolically induced representations of p-adic classical groups
    Location
    Jacob Ziskind Building
    Room 155
    Lecturer
    Hiraku Atobe
    Hokkaido University
    Organizer
    Faculty of Mathematics and Computer Science
    Algebraic Geometry and Representation Theory Seminar
    Contact
    DetailsShow full text description of In this talk, we consider representations of p-adic classica...»
    In this talk, we consider representations of p-adic classical groups parabolically induced from
    the products of shifted Speh representations and unitary representations of Arthur type of good parity.
    We describe how to compute the socles (the maximal semisimple subrepresentations) of these representations algorithmically.
    As a consequence, we can determine whether these representations are reducible or not.
    In particular, our results produce many unitary representations.

    AbstractShow full text abstract about In this talk, we consider representations of p-adic classica...»
    In this talk, we consider representations of p-adic classical groups parabolically induced from
    the products of shifted Speh representations and unitary representations of Arthur type of good parity.
    We describe how to compute the socles (the maximal semisimple subrepresentations) of these representations algorithmically.
    As a consequence, we can determine whether these representations are reducible or not.
    In particular, our results produce many unitary representations.


    Lecture
  • Date:27WednesdayOctober 2021

    Superalgebra Theory and Representations Seminar

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    Time
    19:15 - 20:15
    Title
    Minicourse on Duflo-Serganova functors
    Lecturer
    Alex Sherman (BGU) and Crystal Hoyt (Bar Ilan University)
    .
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar, Department of Computer Science and Applied Mathematics
    Faculty of Mathematical Sciences Seminar, Department of Mathematics
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of ***The mini-course will consist of 3 talks on Wednesdays...»


    ***The mini-course will consist of 3 talks on Wednesdays (Oct. 20th, Oct. 27th, Nov. 3rd), at 19:15 Israel time.
    AbstractShow full text abstract about Given an odd element x in a Lie superalgebra g satisfying [...»
    Given an odd element x in a Lie superalgebra g satisfying [x, x] = 0, we have that x^2 = 0 in the universal enveloping algebra of g, and so for every g-module M, we can define the cohomology DS_x (M) := Ker (x) / Im(x).In fact, DS(M) is a module for the Lie superalgebra g_x := DS_x (g) = Ker ad(x) / Im ad(x), which is a Lie superalgebra of smaller rank than g. For example, if g = gl(m|n) and x is a root vector, then g_x = gl(m − 1|n − 1). Duflo and Serganova defined the functor DS_x from the category of g-modules to the category of g_x-modules which is now called the Duflo–Serganova functor. This minicourse will give an overview of the theory of Duflo–Serganova functors and the recen
    Lecture
  • Date:28ThursdayOctober 2021

    Zoom: “Fast, accessible hyperpolarization for MRI and liquid-state NMR”

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    Time
    09:30 - 10:30
    Lecturer
    Ilai Schwartz
    NVision Imaging Technologies, Ulm
    Organizer
    Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy
    Contact
    DetailsShow full text description of . ...»
    .


    AbstractShow full text abstract about Zoom Lecture: Zoom: : https://weizmann.zoom.us/j/9236283...»
    Zoom Lecture:

    Zoom: : https://weizmann.zoom.us/j/92362836861?pwd=Q29EMVcxaXJkSE5QbWxpUEdPdGNQUT09

    Passcode: 526083


    Nuclear spin hyperpolarization provides a promising route to overcome the challenges imposed by the limited sensitivity of nuclear magnetic resonance. Significant progress in the last decades was achieved by the development of new hyperpolarization techniques (e.g. dissolution-DNP). This has resulted in the demonstration of new MRI applications utilizing hyperpolarized 13C nuclei in metabolic probes as well as promising results in hyperpolarized liquid state NMR. However, hyperpolarization for both MRI and liquid state NMR applications is still a challenging endeavor, requiring expensive hardware and imposing limitations on the experimental setup.

    In this talk I will present our latest developments for achieving fast, accessible polarization for both MRI and NMR applications utilizing a variety of polarization techniques: (1) For MRI applications we have demonstrated for the first time that using parahydrogen induced polarization (PHIP), hyperpolarized fumarate and pyruvate can be prepared at clinically relevant concentrations (> 100mM) and hyperpolarization values up to 20% at the time of injection. In a comparative study we show that PHIP based methods can compete and even surpass both polarization and concentration levels of metabolic tracers prepared by DNP but at a fraction of the cost, complexity and preparation time. (2) Leveraging optical polarization, we developed a technique for versatile liquid state NMR hyperpolarization, achieving between 200- and 1730-fold signal enhancement at 1.45T for a range of small molecules. The signal enhancement is induced by using optically polarized pentacene-doped naphthalene crystals as a source of spin polarization. We demonstrate that rapid dissolution of the highly polarized crystal enables transfer of polarization to the target molecules via intermolecular cross relaxation in the liquid state at room temperature. Due to the extremely high magnetization of the naphthalene molecules, the cross relaxation leads to a substantial polarization buildup in the target analytes. Crucially, the polarization transfer is achieved without costly instrumentation and occurs in less than a minute inside the NMR spectrometer
    Lecture
  • Date:28ThursdayOctober 2021

    PhD defense seminar by Daoud Sheban ( Merbl lab and Hanna lab )

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    Time
    12:00
    Title
    Will lecture on: “Deciphering Mechanisms of SUMO-Dependent Chromatin Regulation in Mammalian Early Development.”
    Lecturer
    Daoud Sheban
    Organizer
    Department of Immunology
    Contact
    DetailsShow full text description of The lecture will take place on Thursday, October 28th, at 12...»
    The lecture will take place on Thursday, October 28th, at 12:00. You are invited to join on Zoom:
    https://weizmann.zoom.us/j/6224628543?pwd=OTNXNHhzUmxRY1hHczZoT1gyMjcrdz09
    Lecture
  • Date:31SundayOctober 202104ThursdayNovember 2021

    SAAC meeting 2021

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    Time
    All day
    Contact
    International Board
  • Date:31SundayOctober 2021

    Promenades through Nobels' landscapes: From disorder & fluctuations to organization in Earth’s climate and other complex systems

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    Time
    11:00
    Location
    https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer
    Michael David Chekroun
    Department of Earth and Planetary Sciences Weizmann Institute of Science
    Organizer
    Department of Earth and Planetary Sciences
    Contact
    Lecture
  • Date:01MondayNovember 2021

    ISBMB annual meeting on Protein Engineering Design and Evolution, Commemorating the work of Professor Dan Tawfik

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    Time
    09:00 - 17:30
    Location
    The David Lopatie Conference Centre
    Contact
    Conference
  • Date:02TuesdayNovember 2021

    Special Guest Seminar

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    Time
    10:00 - 11:00
    Title
    Self-organized morphogenesis of a stem-cell derived human neural tu
    Location
    https://weizmann.zoom.us/j/91871920099?pwd=Qm1kZzc2emV3cGQyekthNWFCOThWdz09
    Lecturer
    Dr. Eyal Karzbrun
    Self-organized morphogenesis of a stem-cell derived human neural tube
    Organizer
    Department of Molecular Genetics
    Contact
    Lecture
  • Date:02TuesdayNovember 2021

    Order from Chaos: Chromosome Catastrophes Drive Cancer Evolution

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    Time
    10:00 - 11:00
    Location
    Nella and Leon Benoziyo Building for Biological Sciences
    Auditorium
    Lecturer
    Dr. Ofer Shoshani
    Dept. of Biomolecular Sciences
    Organizer
    Department of Biomolecular Sciences
    Contact
    AbstractShow full text abstract about Chromosomal instability is one of the major hallmarks in can...»
    Chromosomal instability is one of the major hallmarks in cancer driving numerical and structural chromosome aberrations. Cancer cells can use the chaotic background of chromosome instability to generate ordered genomic events leading to accelerated tumor formation or drug resistance. I will show how chromothripsis, the catastrophic shattering of a chromosome and random religation of its pieces, can promote resistance to therapy. Using cancer cells and patient samples, I identified that chromothripsis drives the formation and evolution of extrachromosomal DNA (ecDNA) elements that can amplify genes conferring drug resistance. I will then discuss how transient centrosome amplification can induce a burst of chromosomal instability in vivo. This triggers the formation of random aneuploidies (changes in chromosome numbers) with cancer initiating cells carrying a specific aneuploidy signature leading to accelerated tumorigenesis. This work has uncovered aneuploidy as a direct driver of cancer and enables a better understanding of the involvement of specific aneuploidies in cancer.
    Lecture
  • Date:02TuesdayNovember 2021

    The Contribution of Epicuticular Wax to Functional Fitness in Tree Tobacco

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    Time
    11:30 - 12:30
    Title
    PhD Thesis Defense seminar
    Location
    Nella and Leon Benoziyo Building for Biological Sciences
    Auditorium
    Lecturer
    Boaz Negin
    Prof. Asaph Aharoni’s Lab, Dept. of Plant and Environmental Sciences - WIS
    Organizer
    Department of Plant and Environmental Sciences
    Contact
    DetailsShow full text description of Host: Prof. Asaph Aharoni...»
    Host: Prof. Asaph Aharoni
    AbstractShow full text abstract about Epicuticular waxes coat the aerial parts of land plants almo...»
    Epicuticular waxes coat the aerial parts of land plants almost ubiquitously. These waxes consist mainly of very long chain fatty acids and their derivatives, though epicuticular wax exact composition may vary greatly between plant species. Despite their wide distribution and decades of extensive study, the role of cuticular lipids in sustaining plant fitness is far from being understood. The main goal of my PhD research has been therefore to answer this fundamental question. To this end, I identified 16 different cuticular lipid related genes based on their enriched expression in the leaf epidermis and slight drought induction and generated knock out mutations in these genes using the CRISPR Cas9 system. Of these 16 mutants, nine displayed a cuticular lipid related phenotype and five were selected for further analysis. The mutated plants had a reduced wax load, or were completely lacking certain wax components altogether. This led to drastic shifts in wax crystal structure and to elevated cuticular water loss, although under non stressed conditions plants with an altered wax composition did not have elevated transpiration. In contrabst, once exposed to drought plants lacking alkanes were not able to strongly reduce their transpiration, leading to leaf death and impaired recovery upon resuscitation. When interactions of snails and insects with this mutant populations were examined, I found that these interactions were best divided based on their type – leaf chewing, phloem feeding or non-feeding interactions. Here I found that fatty alcohols were correlated with reduction in caterpillar weight gain, while cutin but not wax composition affected phloem feeders. Non feeding interactions examined in tobacco white fly showed an effect of wax crystal structure rather than chemical composition. Finally, to examine the effects of epicuticular wax under natural conditions two field plots were planted with these mutants and monitored during several months. I found, that similar to the results of the drought trials, under non-competitive conditions epicuticular wax had little effect on plant fitness. however, when plants were under severe competition with foreign plants, all wax components contributed greatly to fitness. in these plots, similar to the caterpillar assays, caterpillars from a wider range of species preferred the fatty alcohol devoid far mutants. These were also preferred by web weavers, and especially spiders. From this diverse range of settings and interactors I concluded that under optimal conditions, epicuticular wax has little effect on plant fitness. however, once conditions are stressful epicuticular wax contributes greatly whether these conditions be drought, competing vegetation or insect herbivores eating the plants’ leaves. That being said, not all wax components contribute equally to every process. Alkanes are essential for drought recovery while fatty alcohols reduce insect herbivory.
    Lecture
  • Date:02TuesdayNovember 2021

    PhD Thesis Defense seminar by Boaz Negin ( Prof. Asaph Aharoni’s Lab)

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    Time
    11:30 - 12:30
    Location
    Benoziyo Bldg. for Biological Sciences Auditorium - Floor 1
    Lecturer
    Boaz Negin
    Organizer
    Department of Plant and Environmental Sciences
    Contact
    AbstractShow full text abstract about The sinking of organic particles in the ocean and their degr...»
    The sinking of organic particles in the ocean and their degradation by marine microorganisms drive one of the most conspicuous carbon fluxes on Earth, the biological pump. Yet, the mechanisms determining the magnitude of the pump remain poorly understood, limiting our ability to predict this carbon flux in future ocean scenarios. Current ocean models assume that the biological pump is governed by the competition between sinking speed and degradation rate, with the two processes independent from one another. In this talk, I will demonstrate that contrary to this paradigm, sinking itself is a primary determinant of the rate at which bacteria enzymatically degrade particles in the ocean. By combining video microscopy and microfluidic experiments to directly observe and quantify bacterial degradation of individual organic particles in flow, I will show that even modest sinking speeds of 8 meters per day enhance degradation rates more than 10-fold. I will further discuss the molecular mechanism behind the sinking-enhanced degradation, as well as possible ways by which bacteria can slow the sinking of particles. Finally, using the results obtained from a mathematical model, I will show that the coupling of sinking and degradation may contribute to determining the magnitude of the vertical carbon flux in the ocean, and will outline major open questions in the field.
    Lecture
  • Date:02TuesdayNovember 2021

    Brain-wide networks underlying behavior - Insights from functional ultrasound imaging

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    Time
    12:30 - 13:30
    Lecturer
    Dr. Emilie Macé
    Max Planck Institute of Neurobiology, Martinsried, Germany
    Organizer
    Department of Brain Sciences
    Contact
    DetailsShow full text description of Zoom link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1...»
    Zoom link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09

    Meeting ID: 954 0689 3197
    Password: 750421

    Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il tel: 2995
    AbstractShow full text abstract about Functional ultrasound imaging (fUS) is an emerging neuroimag...»
    Functional ultrasound imaging (fUS) is an emerging neuroimaging tool capable of measuring brain-wide vascular signals linked to neuronal activity with a high spatial-temporal resolution (100 µm, 10 Hz) in real-time. This technology is portable, affordable and adaptable to many species, and has already found applications in areas ranging from basic research to the clinic. Focusing on fundamental neuroscience, I will outline some of the recent technical advancements of fUS, such as the capacity to image the entire rodent brain while manipulating specific neuronal circuits with optogenetics. I will exemplify how promising this imaging technique is for shedding new light on the brain-wide circuits underlying behavior, as fUS is one of the few methods that enables imaging of activity deep in the brain of behaving mice.
    Zoom link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09
    Meeting ID: 954 0689 3197
    Password: 750421

    Lecture
  • Date:02TuesdayNovember 2021

    Why Chirality Is Essential for Life

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    Time
    14:00 - 15:00
    Location
    Gerhard M.J. Schmidt Lecture Hall
    Lecturer
    Prof. Ron Naaman
    Department of Chemical and Biological Physics Weizmann Institute
    Organizer
    Department of Chemical and Structural Biology
    Contact
    Lecture
  • Date:03WednesdayNovember 2021

    Superalgebra Theory and Representations Seminar

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    Time
    19:15 - 20:15
    Title
    Minicourse on Duflo-Serganova functors
    Lecturer
    Alex Sherman (BGU) and Crystal Hoyt (Bar Ilan University)
    .
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar, Department of Computer Science and Applied Mathematics
    Faculty of Mathematical Sciences Seminar, Department of Mathematics
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of ***The mini-course will consist of 3 talks on Wednesdays (Oc...»
    ***The mini-course will consist of 3 talks on Wednesdays (Oct. 20th, Oct. 27th, Nov. 3rd), at 19:15 Israel time.
    AbstractShow full text abstract about Given an odd element x in a Lie superalgebra g satisfying [x...»
    Given an odd element x in a Lie superalgebra g satisfying [x, x] = 0, we have that x^2 = 0 in the universal enveloping algebra of g, and so for every g-module M, we can define the cohomology DS_x (M) := Ker (x) / Im(x).In fact, DS(M) is a module for the Lie superalgebra g_x := DS_x (g) = Ker ad(x) / Im ad(x), which is a Lie superalgebra of smaller rank than g. For example, if g = gl(m|n) and x is a root vector, then g_x = gl(m − 1|n − 1). Duflo and Serganova defined the functor DS_x from the category of g-modules to the category of g_x-modules which is now called the Duflo–Serganova functor. This minicourse will give an overview of the theory of Duflo–Serganova functors and the rece
    Lecture
  • Date:04ThursdayNovember 2021

    Physics Colloquium

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    Time
    11:15 - 12:30
    Title
    From Quantum Mechanics to Thermodynamics and Back: On Quantum Systems, Baths and Observers
    Location
    Edna and K.B. Weissman Building of Physical Sciences
    Auditorium
    Lecturer
    Gershon Kurizki
    Weizmann Institute of Science
    Organizer
    Faculty of Physics
    Contact
    DetailsShow full text description of 11:00 - Coffee, Tea and more......»
    11:00 - Coffee, Tea and more...
    AbstractShow full text abstract about Thermodynamics requires a system to equilibrate with its t...»
    Thermodynamics requires a system to equilibrate with its thermal environment, alias a bath. However, our results over the years have shown that, surprisingly, nonintrusive observations of a quantum system may heat or cool it, thus preventing the equilibration [1,2]. Recently, we have shown that also the bath state, which is considered immutable in thermodynamics, is dramatically changed by a quantum probe and its observations [3]. These effects stem from the unavoidable entanglement between quantum systems and baths even when they are weakly coupled, thus undermining the tenets of thermodynamics in the quantum domain. Most remarkably, we have recently demonstrated that probe observations can render thermal bath states nearly pure [4]. The implications are far reaching, most prominently the ability to reverse the time arrow of the entire system-bath compound, by causing its quantum coherent oscillation. This raises the question: Is thermodynamics, which rests on the concept of a bath, compatible with quantum mechanics? It may appear necessary to assume that a quantum working medium in a heat machine is dissipated by a bath [5,6]. Yet, most recently, we have shown that heat machines can be perfectly coherent, non-dissipative devices realized by nonlinear interferometers fed by few thermal modes [7], so that baths are redundant. Finally, I will discuss the ability of observers to commute information to work [8] and speculate on the role of observers in physics [9].

    References to our work
    1. Nature 452, 724 (2008).
    2. PRL 105,160401 (2010).
    3. NJP 22, 083035 (2020).
    4. Arxiv 2108.09826 (2021)
    5. Nat. Commun. 9, 165 (2018).
    6. PNAS 115, 9941 (2018); PNAS 114, 12156 (2017).
    7. Arxiv2108.10157 (2021).
    8. PRL 127, 040602 (2021).
    9. G.Kurizki and G. Gordon, “The Quantum Matrix” (Oxford Univ. Press, 2020).
    Colloquia
  • Date:07SundayNovember 202110WednesdayNovember 2021

    the 73rd Annual General meeting of the International Board

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    Time
    All day
    Location
    David Lopatie Conference Centre
    Kimmel Auditorium
    Contact
    International Board
  • Date:07SundayNovember 2021

    TBA

    More information
    Time
    11:00
    Location
    https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer
    Idan White
    Organizer
    Department of Earth and Planetary Sciences
    Contact
    Lecture
  • Date:08MondayNovember 2021

    Two Hundred Years after Hamilton: Exploring New Formulations of Classical and Quantum Mechanics

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    Time
    11:00 - 12:15
    Location
    https://weizmann.zoom.us/j/98063488104?pwd=N3VqTC9sU1A4RHVDZ1dhOGVxbU1iUT09
    Lecturer
    Prof. David Tannor
    Department of Chemical and Biological Physics, WIS
    Organizer
    Faculty of Chemistry
    Contact
    AbstractShow full text abstract about This talk has three parts. The first part is an introduction...»
    This talk has three parts. The first part is an introduction to Hamilton’s two monumental papers from 1834-1835, which introduced the Hamilton-Jacobi equation, Hamilton’s equations of motion and the principle of least action. These three formulations of classical mechanics became the three forerunners of quantum mechanics; but ironically none of them is what Hamilton was looking for -- he was looking for a “magical” function, the principal function S(q_1,q_2,t) from which the entire trajectory history can be obtained just by differentiation (no integration). In the second part of the talk I argue that Hamilton’s principal function is almost certainly more magical than even Hamilton realized. Astonishingly, all of the above formulations of classical mechanics can be derived just from assuming that S(q_1,q_2,t) is additive, with no input of physics. The third part of the talk will present a new formulation of quantum mechanics in which the Hamilton-Jacobi equation is extended to complex-valued trajectories, allowing the treatment of classically allowed processes, classically forbidden process and arbitrary time-dependent external fields within a single, coherent framework. The approach is illustrated for barrier tunneling, wavepacket revivals, nonadiabatic dynamics, optical excitation using shaped laser pulses and high harmonic generation with strong field attosecond pulses.
    Colloquia
  • Date:09TuesdayNovember 2021

    To be announced

    More information
    Time
    10:00 - 10:00
    Location
    Nella and Leon Benoziyo Building for Biological Sciences
    Cafeteria
    Organizer
    Department of Biomolecular Sciences
    Contact
    Lecture
  • Date:09TuesdayNovember 2021

    Firing Rate Homeostasis in Neural Circuits: From basic principles to malfunctions

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    Time
    12:30
    Location
    Gerhard M.J. Schmidt Lecture Hall
    Lecturer
    Prof. Inna Slutsky
    Head, Dept of Physiology and Pharmacology Sackler Faculty of Medicine, Tel Aviv University
    Organizer
    Department of Brain Sciences
    Contact
    DetailsShow full text description of Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il...»
    Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il tel: 2995
    AbstractShow full text abstract about Maintaining average activity level within a set-point range...»
    Maintaining average activity level within a set-point range constitutes a fundamental property of central neural circuits. Accumulated evidence suggests that firing rate distributions and their means represent physiological variables regulated by homeostatic systems. Utilizing basic concepts of control theory, we developed a theoretical and experimental framework for identifying the core members of homeostatic machinery. I will describe an integrative approach to study the relationships between ongoing spiking activity of individual neurons and neuronal populations in local microcircuits, synaptic transmission and plasticity, sleep and memory functions. I will show our new data on a state-dependent regulation of firing rate set-points, their dysregulation at the presymptomatic stage of Alzheimer’s disease, and the role of mitochondria in these processes.
    Lecture

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