Events

Details: Host-Dr. Yoav Livneh yoav.livneh@weizmann.ac.il tel-6230 For accessibility ... Read more

Abstract: For centuries, consciousness was considered to be outside the reach of scientifi ... Read more For centuries, consciousness was considered to be outside the reach of scientific investigation. Yet in recent decades, more and more studies have tried to probe the neural correlates of conscious experience, and several neuronally-inspired theories for consciousness have emerged. In this talk, I will focus on four leading theories of consciousness: Global Neuronal Workspace (GNW), integrated Information Theory (IIT), Recurrent Processing Theory (RPT) and Higher Order Theory (HOT). I will first shortly present the guiding principles of these theories. Then, I will provide a bird's-eye view of the field, using the results of a large-scale quantitative and analytic review we conducted, examining all studies that either empirically tested these theories or interpreted their findings with respect to at least one of them. Finally, I will describe the first results of the Cogitate consortium - an adversarial collaboration aimed at testing GNW and IIT.

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Beyond Touch: Exploring Audible Aspects of Rodent Whisking

Date:

09

Tuesday

April

2024

Lecture / Seminar

Time: 14:00-15:00

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Ben Efron PhD Thesis Defense

Organizer: Department of Brain Sciences

Details: Zoom:Zoom: https://weizmann.zoom.us/j/95498604599?pwd=eVFqZnBJYTloWjZLOGpkMVhGM1 ... Read more

Abstract: Sensory processing is fundamental for animal adaptation and survival, linking th ... Read more Sensory processing is fundamental for animal adaptation and survival, linking them to their environments. Understanding the nervous system's integration of sensory information is crucial for comprehending behavior and cognition. This process involves integrating external cues across modalities, along with internal states, cognitive processes, and motor control, leading to complex behaviors and a nuanced understanding of the world. To facilitate research on these processes, we aimed to identify natural behaviors that produce both auditory and somatosensory stimuli, steering clear of artificial stimulus sources. We discovered that whisking, previously considered a unimodal behavior associated solely with tactile sensations, also produces sounds with distinctive acoustic features within the auditory frequency range of mice. We explored the auditory neuronal representation of sounds generated by whisking and their implications for behavioral performance. We demonstrate that sounds produced by whisking elicit diverse neuronal responses in the auditory cortex, encoding the object's identity and the mouse's whisking state, even in the absence of tactile sensations. Furthermore, we show that mice are capable of completing behavioral tasks relying solely on auditory cues generated by whisking against objects.

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Information processing in spiking networks: Converging assemblies

Date:

09

Tuesday

April

2024

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Eran Stark

Organizer: Department of Brain Sciences

Details: Host: Dr. Yoav Livneh yoav.livneh@weizmann.ac.il tel:6230 For accessibility i ... Read more

Abstract: How information is processed within the brain is a key question in systems neuro ... Read more How information is processed within the brain is a key question in systems neuroscience. We address the issue in spiking neuronal networks of freely moving mice. I will describe our recent findings and conclusions pertaining to three specific information processing steps: transmission, representation, and storage. First, using feedforward optogenetic injection of white noise input to a small group of adjacent neocortical excitatory cells, we find that spike transmission to a postsynaptic cell exhibits error correction, improved precision, and temporal coding. The results are consistent with a nonlinear coincidence detection model in the postsynaptic neuron. Second, by triggering input on animal kinematics, we create an artificial place field in an otherwise-silent pyramidal cell. In hippocampal region CA1 but not in the neocortex, artificial fields exhibit synthetic phase precession that persists for a full cycle. The local conversion of an induced rate code into an emerging phase code is compatible with a dual-oscillator interference model. Third, by triggering input on spontaneous spiking, we impose self-terminating spike patterns in a group of presynaptic excitatory neurons and a postsynaptic cell. The precise timing of all pre- and postsynaptic spikes has a more substantial impact on long-lasting effective connectivity than that of individual cell pairs, revealing an unexpected plasticity mechanism. We conclude that intrinsic properties of single neurons support millisecond-timescale operations, and that cortical networks are organized in functional modules which we refer to as “converging assemblies”.

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Studying Ageing and Neurodegenerative Brain with Quantitative MRI

Date:

02

Tuesday

April

2024

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Aviv Mezer

Organizer: Department of Brain Sciences

Details: Host: Yoav Livneh yoav.livneh@weizmann.ac.il tel:6230 For accessibility issue ... Read more

Abstract: Aging and neurodegeneration are associated with changes in brain tissue at the m ... Read more Aging and neurodegeneration are associated with changes in brain tissue at the molecular level, affecting its organization, density, and composition. These changes can be detected using quantitative MRI (qMRI), which provides physical measures that are sensitive to structural alterations. However, a major challenge in brain research is to relate physical estimates to their underlying biological sources. In this talk, I will discuss the community's efforts to use qMRI to identify biological processes that underlie changes in brain tissue. Specifically, I will highlight approaches for differentiating between changes in the concentration and composition of myelin and iron during aging. By exploring the molecular landscape of the aging and neurodegenerative brain using qMRI, we aim to gain a better understanding of these processes and potentially provide new metrics for evaluating them.

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Hippocampal pathology and pathophysiology in the development of temporal lobe epileptogenesis

Date:

24

Sunday

March

2024

Lecture / Seminar

Time: 11:00-12:00

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Robert S. Sloviter

Organizer: Department of Brain Sciences

Details: Host: Prof. Menahem Segal menahem.segal@weizmann.ac.il For accessibility issu ... Read more

Abstract: In families with febrile seizures and temporal lobe epilepsy, mutations affectin ... Read more In families with febrile seizures and temporal lobe epilepsy, mutations affecting different GABAergic mechanisms suggest that failure of chloride conductance to limit depolarization may be directly epileptogenic. This “GABAergic disinhibition” hypothesis has been discounted historically for two reasons. First, early attempts to produce hippocampal sclerosis and epilepsy simply by eliminating hippocampal GABA neurons consistently failed to do so. Second, the notion persists that because clinical epilepsy diagnosis is typically delayed for years or decades after brain injury, temporal lobe epileptogenesis should be presumed to involve a complex pathological transformation process that reaches completion during this “latent period.” Recent advances clarify both issues. Although spatially limited hippocampal GABA neuron ablation causes only submaximal granule cell hyperexcitability, more spatially extensive ablation maximizes granule cell hyperexcitability and triggers nonconvulsive granule cell status epilepticus, hippocampal sclerosis, and epilepsy. Recent studies also show that disinhibited granule cells begin to generate clinically subtle seizures immediately post-injury, and these seizures then gradually increase in duration to become clinically obvious. Therefore, rather than being a seizure-free “gestational” state of potentially interruptible epileptogenesis, the “latent period” is more likely an active epileptic state when barriers to seizure spread and clinical expression are gradually overcome by a kindling process. The likelihood that an epileptic brain state exists long before clinical diagnosis has significant implications for anti-epileptogenesis studies. The location, magnitude, and spatial extent of inherited, autoimmune, and injury-induced disinhibition may determine the latency to clinical diagnosis and establish the continuum between the benign, treatable, and refractory forms of temporal lobe epilepsy.

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Allosteric modulation of protein kinase A in individuals affected by NLPD-PKA , a neurodegenerative disease in which the RIß-L50R variant is expressed

Date:

21

Thursday

March

2024

Lecture / Seminar

Time: 15:00-16:00

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Dr. Ronit Ilouz

Organizer: Department of Biomolecular Sciences

Details: Protein Kinase A (PKA) plays a crucial role in regulating neuronal functions, an ... Read more

The Golden Approach for Overcoming Bio-Barriers: Delivering Nanomedicine to Brain and Beyond

Date:

21

Thursday

March

2024

Lecture / Seminar

Time: 14:00-15:00

Location: Max and Lillian Candiotty Building

Lecturer: Prof. Rachela Popovtzer

Organizer: Dwek Institute for Cancer Therapy Research

Contact: michalav@weizmann.ac.il

Details: Meeting URL: https://weizmann.zoom.us/j/5065402023?pwd=a3Z6KzRCU0xJaUFoM2Y5emZwZ ... Read more

A brain-computer interface for studying long-term changes of hippocampal neural codes

Date:

13

Wednesday

March

2024

Lecture / Seminar

Time: 15:30-16:30

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Linor Baliti Turgeman-PhD Thesis Defense

Organizer: Department of Brain Sciences

Details: Student Seminar-PhD Thesis Defense

Abstract: Brain-computer interfaces (BCI), have important applications both in medicine an ... Read more Brain-computer interfaces (BCI), have important applications both in medicine and as a research tool. Typically, BCIs rely on electrode arrays to capture electrical signals, which are then processed by algorithms to translate neural activity into actions of an external device. However, these electrophysiological techniques are often inadequate for tracking large populations of the same neurons over timescales longer than ~1 day. To address this, we developed calcium imaging-based BCI for freely behaving mice, facilitating continuous recording and analysis of specific neuronal populations over extended periods. This BCI allowed investigating the long-term neuronal coding dynamics in the hippocampus, revealing changes in neuronal population activity both within and across days. I am hopeful that this BCI will advance studies on spatial cognition and long-term memory.

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Travelling waves or sequentially activated modules: mapping the granularity of cortical propagation

Date:

12

Tuesday

March

2024

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Mark Shein-Idelson

Organizer: Department of Brain Sciences

Details: Host: Dr. Yoav Livneh yoav.livneh@weizmann.ac.il tel:6230 For accessibility ... Read more

Abstract: : Numerous studies have identified travelling waves in the cortex and suggested ... Read more : Numerous studies have identified travelling waves in the cortex and suggested they play important roles in brain processing. These waves are most often measured using macroscopic methods that do not allow assessing wave dynamics at the single neuron scale and analyzed using techniques that smear neuronal excitability boundaries. In my talk, I will present a new approach for discriminating travelling waves from modular activation. Using this approach I will show that Calcium dynamics in mouse cortex and spiking activity in turtle cortex are dominated by modular activation rather than by propagating waves. I will then show how sequentially activating two discrete brain areas can appear as travelling waves in EEG simulations and present an analytical model in which modular activation generates wave-like activity with variable directions, velocities, and spatial patterns. I will end by illustrating why a careful distinction between modular and wave excitability profiles across scales will be critical for understanding the nature of cortical computations.

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The Clore Center for Biological Physics

Date:

03

Sunday

March

2024

Lecture / Seminar

Time: 13:15-14:30

Title: A Statistical Physics Approach to Bacteria under Strong Perturbations

Location: Nella and Leon Benoziyo Physics Library

Lecturer: Prof. Nathalie Q. Balaban

Organizer: Clore Center for Biological Physics

Contact: debbie.hen@weizmann.ac.il

Details: refreshments will be served at 12:45

Abstract: Statistical physics successfully accounts for phenomena involving a large number ... Read more Statistical physics successfully accounts for phenomena involving a large number of components using a probabilistic approach with predictions for collective properties of the system. While biological cells contain a very large number of interacting components, (proteins, RNA molecules, metabolites, etc.), the cellular network is understood as a particular, highly specific, choice of interactions shaped by evolution, and therefore difficultly amenable to a statistical physics description. Here we show that when a cell encounters an acute but non-lethal stress, its perturbed state can be modelled as random network dynamics. Strong perturbations may therefore reveal the dynamics of the underlying network that are amenable to a statistical physics description. We show that our experimental measurements of the recovery dynamics of bacteria from a strong perturbation can be described in the framework of physical aging in disordered systems (Kaplan Y. et al, Nature 2021). Further experiments on gene expression confirm predictions of the model. The predictive description of cells under and after strong perturbations should lead to new ways to fight bacterial infections, as well as the relapse of cancer after treatment.

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Highly multiplexed imaging of tissues with subcellular resolution by imaging mass cytometry

Date:

29

Thursday

February

2024

Lecture / Seminar

Time: 14:00

Lecturer: Prof. Bernd Bodenmiller

Organizer: Dwek Institute for Cancer Therapy Research

Contact: michalav@weizmann.ac.il

Details: Meeting URL: https://weizmann.zoom.us/j/5065402023?pwd=a3Z6KzRCU0xJaUFoM2Y5emZw ... Read more

Immunology and Regenerative Biology Colloquium

Date:

28

Wednesday

February

2024

Lecture / Seminar

Time: 11:00-12:00

Title: Multi-Potent Lung Stem Cells for Lung Regeneration

Location: Max and Lillian Candiotty Building

Lecturer: Prof. Yair Reisner

Organizer: Department of Immunology and Regenerative Biology

Contact: ronen.alon@weizmann.ac.il

Mapping the world around us: A topology-preserved schema of space that supports goal-directed navigation

Date:

20

Tuesday

February

2024

Lecture / Seminar

Time: 12:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Raunak Basu

Organizer: Department of Brain Sciences

Details: Host: Dr. Yoav Livneh yoav.livneh@weizmann.ac.il For accessibility issues: na ... Read more

Abstract: Successful goal-directed navigation requires estimating one’s current position ... Read more Successful goal-directed navigation requires estimating one’s current position in the environment, representing the future goal location, and maintaining a map that preserves the topological relationship between positions. In addition, we often need to implement similar navigational strategies in a continuously changing environment, thereby necessitating certain invariance in the underlying spatial maps. Previous research has identified neurons in the hippocampus and parahippocampal cortices that fire specifically when an animal visits a particular location, implying the presence of a spatial map in the brain. However, this map largely encodes the current position of an animal and is context-dependent, whereby changing the room or shape of the arena results in a new map orthogonal to the previous one. These observations raise the question, are there other spatial maps that fulfill the cognitive requirements necessary for goal-directed navigation? Using a goal-directed navigation task with multiple reward locations, we observed that neurons in the orbitofrontal cortex (OFC) exhibit distinct firing patterns depending on the goal location, and this goal-specific OFC activity originates even before the onset of the journey. Further, the difference in the ensemble firing patterns representing two target locations is proportional to the physical distance between these locations, implying the preservation of spatial topology. Finally, carrying out the task across different spatial contexts revealed that the mapping of target locations in the OFC is largely preserved and that the maps formed in two different contexts occupy similar neural subspaces and could be aligned by a linear transformation. Taken together, the OFC forms a topology-preserved schema of spatial locations that is used to represent the future spatial goal, making it a potentially crucial brain region for planning context-invariant goal-directed navigational strategies.

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iSCAR seminar

Date:

19

Monday

February

2024

Lecture / Seminar

Time: 09:00-10:00

Title: The ultimate sacrifice? The germline regulates longevity and somatic repair in a sex-specific manner

Location: Max and Lillian Candiotty Building

Lecturer: Dr. Itamar Harel

Organizer: Department of Immunology and Regenerative Biology

Contact: karina.yaniv@weizmann.ac.il

The role of the corpus callosum in interhemispheric communication

Date:

14

Wednesday

February

2024

Lecture / Seminar

Time: 14:00-15:00

Location: The David Lopatie Hall of Graduate Studies

Lecturer: Yael Oran-PhD Thesis Defense

Organizer: Department of Brain Sciences

Details: Student Seminar-PhD Thesis Defense

Abstract: Interhemispheric communication is a comprehensive concept that involves both the ... Read more Interhemispheric communication is a comprehensive concept that involves both the synchronization of neural activity as well as the integration of sensory information across the two brain hemispheres. In this work, we explored these properties in the somatosensory system of the mouse brain. We show that during spontaneous activity in awake animals, robust interhemispheric correlations of both spiking and synaptic activities that are reduced during whisking compared to quiet wakefulness. And that the state-dependent correlations between the hemispheres stem from the state-depended nature of the corpus callosum activity. Further, to understand how sensory information is integrated across the brain's hemispheres, we studied bilateral and ipsilateral responses to passive whisker stimulation using widefield imaging and then employed a virtual tunnel environment to explore bilateral integration in active whisking

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Vision and AI

Date:

08

Thursday

February

2024

Lecture / Seminar

Time: 12:15-13:15

Title: Strong and Precise Modulation of Human Percepts via Robustified ANNs

Location: Jacob Ziskind Building

Lecturer: Guy Gaziv

Organizer: Department of Computer Science and Applied Mathematics

Abstract: The visual object category reports of artificial neural networks (ANNs) are noto ... Read more The visual object category reports of artificial neural networks (ANNs) are notoriously sensitive to tiny, adversarial image perturbations. Because human category reports (aka human percepts) are thought to be insensitive to those same small-norm perturbations — and locally stable in general — this argues that ANNs are incomplete scientific models of human visual perception. Consistent with this, we show that when small-norm image perturbations are generated by standard ANN models, human object category percepts are indeed highly stable. However, in this very same "human-presumed-stable" regime, we find that robustified ANNs reliably discover low-norm image perturbations that strongly disrupt human percepts. These previously undetectable human perceptual disruptions are massive in amplitude, approaching the same level of sensitivity seen in robustified ANNs. Further, we show that robustified ANNs support precise perceptual state interventions: they guide the construction of low-norm image perturbations that strongly alter human category percepts toward specific prescribed percepts. These observations suggest that for arbitrary starting points in image space, there exists a set of nearby "wormholes", each leading the subject from their current category perceptual state into a semantically very different state. Moreover, contemporary ANN models of biological visual processing are now accurate enough to consistently guide us to those portals. project webpage Bio: Guy is a Computer Vision postdoctoral researcher at the DiCarlo Lab at MIT, interested in the intersection between machine and human vision. His PhD focused on decoding visual experience from brain activity. His current focus is on harnessing contemporary models of primate visual cognition for neural and behavioral modulation. Guy holds a PhD in Computer Science and an MSc in Physics from The Weizmann Institute of Science, and a BSc in Physics-EECS from The Hebrew University of Jerusalem.

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Geometric Functional Analysis and Probability Seminar

Date:

01

Thursday

February

2024

Lecture / Seminar

Time: 13:30-14:30

Title: Scaling limits for growth driven by reflecting Brownian motion

Location: Jacob Ziskind Building

Lecturer: Amir Dembo

Organizer: Department of Mathematics

Contact: hany.kochavi@weizmann.ac.il

Abstract: In joint works with Kevin Yang, we consider a stochastic Laplacian growth model, ... Read more In joint works with Kevin Yang, we consider a stochastic Laplacian growth model, that can be viewed as a continuum version of origin-excited random walks. Here, we grow the (d 1)-dimensional manifold M(t) according to a reflecting Brownian motion (RBM) on M(t), stopped at level sets of its boundary local time. An averaging principle for the RBM characterizes the scaling limit for the leading order behavior of the interface (namely, the boundary of M(t)). This limit is given by a locally well-posed, geometric flow-type PDE, whose blow-up times correspond to changes in the diffeomorphism class of the growing set. Smoothing the interface as we inflate M(t), yields an SPDE for the large-scale fluctuations of an associated height function. This SPDE is a regularized KPZ-type equation, modulated by a Dirichlet-to-Neumann operator. For d=1 we can further remove the regularization, so the fluctuations of M(t) now have a double-scaling limit given by a singular KPZ-type equation.

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One molecular- and one circuit-level insight into cognition from studying Drosophila

Date:

30

Tuesday

January

2024

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Gaby Maimon

Organizer: Department of Brain Sciences

Details: Host: Yoav Livneh yoav.livneh@weizmann.ac.il tel:6230 For accessibility issue ... Read more

Abstract: A major goal of cognitive neuroscience is to clarify the functions of central br ... Read more A major goal of cognitive neuroscience is to clarify the functions of central brain regions. Over the past decade, the high-level functional architecture of a region in the middle of the insect brain––the central complex––has come into focus. I will start by briefly summarizing our understanding of the central complex as a microcomputer that calculates the values of angles and two-dimensional vectors important for guiding navigational behavior. I will then describe some recent findings on this brain region, revealing (1) how neuronal calcium spikes, mediated by T-type calcium channels, augment spatial-vector calculations and (2) how an angular goal signal is converted into a locomotor steering signal. These results provide inspiration for better understanding the roles of calcium spikes and goal signals in mammalian brains.

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Geometric Functional Analysis and Probability Seminar

Date:

25

Thursday

January

2024

Lecture / Seminar

Time: 13:30-14:30

Title: Determinants of Laplacians and heat-kernel bounds

Location: Jacob Ziskind Building

Lecturer: Renan Gross

Organizer: Department of Mathematics

Contact: hany.kochavi@weizmann.ac.il

Abstract: In this talk, we will smash together spanning trees, Brownian motion and negativ ... Read more In this talk, we will smash together spanning trees, Brownian motion and negative-curvature manifolds. The "tree entropy" of a converging sequence of graphs roughly counts how many spanning trees per vertex each graph has, and can be calculated using the Laplacian of the graph. A similar quantity can be defined for compact hyperbolic surfaces, but is much trickier to compute. In this talk we will discuss spectral and geometric conditions which lead to its convergence for locally-converging surfaces. The proof involves analyzing the return density of Brownian motion to the origin, averaged over the entire surface.

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Non-canonical circuits for olfaction

Date:

16

Tuesday

January

2024

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Dan Rokni

Organizer: Department of Brain Sciences

Details: Host: Yoav Livneh yoav.livneh@weizmann.ac.il tel: 6230 For accessibility issu ... Read more

Abstract: : I’ll describe two projects: In the first, we examined the circuitry that un ... Read more : I’ll describe two projects: In the first, we examined the circuitry that underlies olfaction in a mouse model with severe developmental degeneration of the OB. The olfactory bulb (OB) is a critical component of mammalian olfactory neuroanatomy. Beyond being the first and sole relay station for olfactory information to the rest of the brain, it also contains elaborate stereotypical circuitry that is considered essential for olfaction. In our mouse model, a developmental collapse of local blood vessels leads to degeneration of the OB. Mice with degenerated OBs could perform odor-guided tasks and even responded normally to innate olfactory cues. I will describe the aberrant circuitry that supports functional olfaction in these mice. The second project focusses on the nucleus of the lateral olfactory tract. This amygdaloid nucleus is typically considered part of the olfactory cortex, yet almost nothing is known about its function, connectivity, and physiology. I will describe our approach to studying this intriguing structure and will present some of its cellular and synaptic properties that may guide hypotheses about its function.

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How Do Muscle Fibers Grow and Regenerate?

Date:

16

Tuesday

January

2024

Lecture / Seminar

Time: 10:00-11:00

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Sharon Havusha-Laufer

Organizer: Department of Biomolecular Sciences

Abstract: The skeletal muscle tissue that allows our bodies to move, is comprised of enorm ... Read more The skeletal muscle tissue that allows our bodies to move, is comprised of enormous muscle fibers, termed myofibers. Myofibers must grow with our body and adapt to its needs throughout life. This is accomplished by adding nuclei via cell-to-cell fusion. However, the fusion mechanism is poorly understood. To gain a better understanding of the fusion and repair mechanisms I recapitulated myoblast-to-myofiber fusion in culture, which allowed me for the first time to visualize the fusion and regeneration processes at high resolution, generating the seminal observations that form the central hypothesis for my PhD.

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Immunoception: Brain Representation and Control of Immunity

Date:

09

Tuesday

January

2024

Lecture / Seminar

Time: 13:00

Location: Wolfson Building for Biological Research

Lecturer: Prof. Asya Rolls

Organizer: Department of Brain Sciences

Details: Host. Dr. Yoav Livneh yoav.livneh@weizmann.ac.il For accessibility issues: na ... Read more

Abstract: To function as an integrated entity, the organism must synchronize between behav ... Read more To function as an integrated entity, the organism must synchronize between behavior and physiology. Our research focuses on probing this synchronization through the lens of the brain-immune system interface. The immune system, pivotal in preserving the organism's integrity, is also a sensitive barometer of its overall state. I will discuss the emerging understanding of how the brain represents the state of the immune system and the specific neural mechanisms that enable the brain to orchestrate immune responses.

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Special Clore Seminar - Leenoy Meshulam

Date:

09

Tuesday

January

2024

Lecture / Seminar

Time: 12:45-13:45

Title: Bridging scales in biological systems – from octopus skin to mouse brain

Location: Nella and Leon Benoziyo Physics Building

Lecturer: Leenoy Meshulam

Organizer: Clore Center for Biological Physics

Contact: malka.avraham@weizmann.ac.il

Details: Lunch will be held at 12:15

Abstract: For an animal to perform any function, millions of cells in its body furiously i ... Read more For an animal to perform any function, millions of cells in its body furiously interact with each other. Be it a simple computation or a complex behavior, all biological functions involve the concerted activity of many individual units. A theory of function must specify how to bridge different levels of description at different scales. For example, to predict the weather, it is theoretically irrelevant to follow the velocities of every molecule of air. Instead, we use coarser quantities of aggregated motion of many molecules, e.g., pressure fields. Statistical physics provides us with a theoretical framework to specify principled methods to systematically ‘move’ between descriptions of microscale quantities (air molecules) to macroscale ones (pressure fields). Can we hypothesize equivalent frameworks in living systems? How can we use descriptions at the level of cells and their connections to make precise predictions of complex phenomena My research group will develop theory, modeling and analysis for a comparative approach to discover generalizable forms of scale bridging across species and behavioral functions. In this talk, I will present lines of previous, ongoing, and proposed research that highlight the potential of this vision. I shall focus on two seemingly very different systems: mouse brain neural activity patterns, and octopus skin cells activity patterns. In the mouse, we reveal striking scaling behavior and hallmarks of a renormalization group- like fixed point governing the system. In the octopus, camouflage skin pattern activity is reliably confined to a (quasi-) defined dynamical space. Finally, I will touch upon the benefits of comparing across animals to extract principles of multiscale function in biological systems, and propose future directions to investigate how macroscale properties, such as memory or camouflage, emerge from microscale level activity of individual cells.

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Chemical and Biological Physics Guest seminar

Date:

07

Sunday

January

2024

Lecture / Seminar

Time: 15:00

Title: Static and dynamic biophysical properties of tissue microstructure: Insights from advanced in vivo MRI

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr Noam Shemesh

Organizer: Department of Chemical and Biological Physics

Contact: daniella.goldfarb@weizmann.ac.il

Abstract: In living systems, the tissue micro-architecture consists of myriad cellular and ... Read more In living systems, the tissue micro-architecture consists of myriad cellular and subcellular elements whose density, size/shape distributions, composition, and permeability, endow the tissue with its biological functionality. Dynamic transport mechanisms are further critical for maintaining homeostasis and supporting diverse physiological functions such as action potentials and biochemical signaling. Still, how these biophysical properties change over time and how they couple to activity, remains largely unknown. This is mainly due to the difficulty in mapping these properties in-vivo, longitudinally, and with sufficient specificity. Magnetic Resonance Imaging (MRI), with its capacity for longitudinal studies and wealth of microscopic information leading to multiple contrast mechanisms, provides an outstanding opportunity to decipher these phenomena. In this talk I will discuss our recent advances in diffusion and functional MRI, including novel pulse sequences and biophysical modeling of diffusion processes in the microscopic tissue milieu, which provide, for the first time, the sought-after specificity for density, size, and permeability of particular (sub)cellular elements in tissues. I will show new experiments in rodents proving unique power-laws predicted from biophysical models, revealing axon density and size, as well as cell body density and size, along with validations against ground-truth histology and applications in animal models of disease. Evidence for exchange between the intracellular and extracellular space will also be given, along with a first approach for quantitatively mapping permeability in tissue. I will also introduce correlation tensor MRI (CTI), a new approach for source-separation in diffusional kurtosis, that offers surrogate markers of neurite beading effects, thereby further enhancing specificity, especially in stroke. Finally, I will touch upon dynamic modulations of neural tissue microstructure upon neural activity, and provide evidence for the existence of a neuro-morphological coupling in diffusion-weighted functional MRI signals. Future vistas and potential applications will be discussed.

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Clore Seminar-Professor Jay Fineberg

Date:

07

Sunday

January

2024

Lecture / Seminar

Time: 13:15-14:15

Title: The Fundamental Physics of the Onset of Frictional Motion: How do laboratory earthquakes nucleate?

Location: Nella and Leon Benoziyo Physics Building

Lecturer: Prof. Jay Fineberg

Organizer: Clore Center for Biological Physics

Contact: malka.avraham@weizmann.ac.il

Details: Lunch at 12:45

Abstract: Recent experiments have demonstrated that rapid rupture fronts, akin to earthqua ... Read more Recent experiments have demonstrated that rapid rupture fronts, akin to earthquakes, mediate the transition to frictional motion. Moreover, once these dynamic rupture fronts (“laboratory earthquakes”) are created, their singular form, dynamics and arrest are well-described by fracture mechanics. Ruptures, however, need to be created within initially rough frictional interfaces, before they are able to propagate. This is the reason that “static friction coefficients” are not well-defined; frictional ruptures can nucleate for a wide range of applied forces. A critical open question is, therefore, how the nucleation of rupture fronts actually takes place. We experimentally demonstrate that rupture front nucleation is prefaced by extremely slow, aseismic, nucleation fronts. These nucleation fronts, which are often self-similar, are not described by our current understanding of fracture mechanics. The nucleation fronts emerge from initially rough frictional interfaces at well-defined stress thresholds, evolve at characteristic velocity and time scales governed by stress levels, and propagate within a frictional interface to form the initial rupture from which fracture mechanics take over. These results are of fundamental importance to questions ranging from earthquake nucleation and prediction to processes governing material failure.

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Chemical and Biological Physics Guest seminar

Date:

03

Wednesday

January

2024

Lecture / Seminar

Time: 15:00-16:00

Title: Atomic arrays as programmable quantum processors and sensors

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr Ran Finkelstein

Organizer: Department of Chemical and Biological Physics

Contact: lucio.frydman@weizmann.ac.il

Abstract: Large arrays of trapped neutral atoms have emerged over the past few years as a ... Read more Large arrays of trapped neutral atoms have emerged over the past few years as a promising platform for quantum information processing, combining inherent scalability with high-fidelity control and site-resolved readout. In this talk, I will discuss ongoing work with arrays of Alkaline-earth atoms. These divalent atoms offer unique properties stemming largely from their long-lived metastable states, which form the basis of the optical atomic clock. I will describe the design of a universal quantum processor based on clock qubits and its application in quantum metrology, and I will address the challenge of generating and benchmarking highly entangled states in an analog quantum simulator. First, we realize scalable local control of individual clock qubits, which we utilize to extend the Ramsey interrogation time beyond the coherence time of a single atom [1]. To realize a universal quantum processor, we demonstrate record high-fidelity two-qubit entangling gates mediated by Rydberg interactions, which we combine with dynamical reconfiguration to entangle clock probes in GHZ states and perform Ancilla-based detection [2]. We then use the narrow clock transition to measure and remove thermal excitations of atoms in tweezers (a technique known as erasure conversion) and generate hyperentangled states of motion and spin [3]. In the second part of the talk, I will describe a different approach for generating large scale entangled states in an analog quantum simulator configuration [4], including error mitigation [5] and benchmarking of a 60-atom simulator [6]. Together, these show the great promise and the large variety of experiments accessed with this emerging platform. [1] A. Shaw*, R. Finkelstein*, R. Tsai, P. Scholl, T. Yoon, J. Choi, M. Endres, Multi-ensemble metrology by programming local rotations with atom movements, arxiv:2303.16885, Nature Physics in press (2023). [2] R. Finkelstein, R. Tsai, A. Shaw, X. Sun, M. Endres, A universal quantum processor for entanglement enhanced optical tweezer clocks, in preparation. [3] P. Scholl*, A. Shaw*, R. Finkelstein*, R. Tsai, J. Choi, M. Endres, Erasure cooling, control, and hyper-entanglement of motion in optical tweezers, arXiv:2311.15580 (2023). [4] J. Choi, A. Shaw, I. Madjarov, X. Xie, R. Finkelstein, J. Covey, J. Cotler, D. Mark, H.Y. Huang, A. Kale, H. Pichler, F. Brandão, S. Choi, and M. Endres, Preparing random states and benchmarking with many-body quantum chaos, Nature 617 (2023) [5] P. Scholl, A. Shaw, R. Tsai, R. Finkelstein, J. Choi, M. Endres, Erasure conversion in a high-fidelity Rydberg quantum simulator, Nature 622 (2023). [6] A. Shaw, Z. Chen, J. Choi, D.K. Mark, P. Scholl, R. Finkelstein, A. Elben, S. Choi, M. Endres, Benchmarking highly entangled states on a 60-atom analog quantum simulator, arXiv:2308.07914 (2023).

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Special Guest Seminar: Dr. Sharon Fleischer

Date:

03

Wednesday

January

2024

Lecture / Seminar

Time: 10:00-12:00

Title: Stem cell based cardiac tissue models to study the human heart in health and disease

Location: Wolfson Building for Biological Research

Lecturer: Dr. Sharon Fleischer

Organizer: Department of Molecular Cell Biology

Contact: michal.ovadia@weizmann.ac.il

A paradigm shift in GPCR recruitment and activity: GPCR Voltage Dependence Controls Neuronal Plasticity and Behavior

Date:

02

Tuesday

January

2024

Lecture / Seminar

Time: 00:00

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Moshe Parnas

Organizer: Department of Brain Sciences

Spatial Biology by Imaging Mass Cytometry Lecture / Seminar website

Abstract: : G-protein coupled receptors (GPCRs) play a paramount role in diverse brain fun ... Read more : G-protein coupled receptors (GPCRs) play a paramount role in diverse brain functions. Twenty years ago, GPCR activity was shown to be regulated by membrane potential in vitro, but whether the voltage dependence of GPCRs contributes to neuronal coding and behavioral output under physiological conditions in vivo has never been demonstrated. We show in two different processes that muscarinic GPCR mediated neuromodulation in vivo is voltage dependent. First, we show that muscarinic type A receptors (mAChR-A) mediated neuronal potentiation is voltage dependent. This potentiation voltage dependency is abolished in mutant flies expressing a voltage independent receptor. Most important, muscarinic receptor voltage independence caused a strong behavioral effect of increased odor habituation. Second, we show that muscarinic type B receptors (mAChR-B) voltage dependency is required for both efficient and accurate learning and memory. Normally, to prevent non-specific olfactory learning and memory, mAChR-B activity suppress both signals that are required for plasticity. Behavior experiments demonstrate that mAChR-B knockdown impairs olfactory learning by inducing undesired changes to the valence of an odor that was not associated with the reinforcer. On the other hand, mAChR-B voltage dependence prevents mAChR-B to interfere with plasticity in neurons that are required for the learning and memory process. Indeed, generating flies with a voltage independent mAChR-B resulted in impaired learning. Thus, we provide the very first demonstrations of physiological roles for the voltage dependency of GPCRs by demonstrating crucial involvement of GPCR voltage dependence in neuronal plasticity and behavior. As such, our findings create a paradigm shift in our thinking on GPCR recruitment and activity. Together, we suggest that GPCR voltage dependency plays a role in many diverse neuronal functions including learning and memory and may serve as a target for novel drug development. Light refreshments before the seminar.

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Spatial Biology by Imaging Mass Cytometry

Date:

07

Thursday

December

2023

Lecture / Seminar

Time: 09:00-10:00

Location: ZOOM

Lecturer: Dr. Sean Pawlowski(Ionpath) & Dr. Tomer-Meir Salame (LSCF)

Organizer: Department of Life Sciences Core Facilities

Contact: tomer-meir.salame@weizmann.ac.il

Gallery: Spatial Biology by Imaging Mass Cytometry Gallery

Context-Dependent Dynamic Coordination of Head and Eye Movements During Visual Orienting

Date:

06

Wednesday

December

2023

Lecture / Seminar

Time: 14:00-15:00

Lecturer: Ofer Karp-PhD Defense seminar

Organizer: Department of Brain Sciences

Details: Zoom link: https://weizmann.zoom.us/j/98466393859?pwd=blJkSDUyWkR0L2FhQUFueS9FY2 ... Read more

Abstract: The orienting response, described by Pavlov as the “what is it?” reflex, aim ... Read more The orienting response, described by Pavlov as the “what is it?” reflex, aims to describe an individual's reaction to unexpected stimuli in their environment. Many experimental results show that in such an event, the quickest motor response is of a saccadic eye movement, and if the head is free to move, a head-shift follows the eye to meet the event. Studying orienting in different tasks and contexts have uncovered several variations in head-eye coordination, including modulations of the number of saccades during a single orienting motion and modulations of the relative timing between head and eye movements. In this presentation, I will present my attempt at understanding and modeling the brain-environment loops underlying the visual orienting response. For this aim I have designed and constructed a virtual reality (VR) setting that allows head and eye real-time tracking during visual tasks in different contexts. I will show that, with head-free viewing, the classic eye-leading, fast saccadic gaze-shift response is typical for cases of external visual stimuli. In contrast, multi-saccadic, head-leading gaze-shifts are typical for cases in which the subject orients towards an internal reference position, with no external visual que, regardless of the angle. I demonstrate that the kinematics of the first saccadic eye movement is different between the two conditions, suggesting different motor control mechanisms. My results suggest that the context of orienting, whether it is exogenous (targeting an external stimulus) or endogenous (targeting an internal reference point) affects the balance between the two mechanisms. A comparison of the orienting responses towards visual versus auditory stimuli suggests different modalities (such as auditory and proprioceptive) are treated as endogenous by the visual control system. Based on these results, I suggest a competitive multiple-closed-loop dynamic model of gaze orienting. Simulations of the model show it can replicate the empirical kinematics and statistics. My results suggest that the traditional view of the mechanism underlying gaze orienting response should be revisited to take into account the source of the response as well as the subjective context of orienting. I propose that the closed-loop model for orienting presented here can address this aspect. If accepted, this model can facilitate the diagnosis and treatment of several oculomotor impairments. Zoom: https://weizmann.zoom.us/j/98466393859?pwd=blJkSDUyWkR0L2FhQUFueS9FY2lwZz09 Id: 98466393859 passcode: 059130

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Dissecting the role of peripheral immunity in Alzheimer’s Disease pathogenesis and disease course

Date:

23

Thursday

November

2023

Lecture / Seminar

Time: 11:30-12:30

Title: Student Seminar PhD Thesis Defense ZOOM

Lecturer: Tommaso Croese PhD Defense

Organizer: Department of Brain Sciences

Details: Zoom Link: https://weizmann.zoom.us/j/5420322495?pwd=ZmhUR0kxWTB6aDh0bklBNFlzV1J ... Read more

Abstract: Recent research has increasingly focused on the intricate interactions between t ... Read more Recent research has increasingly focused on the intricate interactions between the brain and the immune system, a critical line of inquiry for understanding neurological disorders like Alzheimer's Disease (AD). AD, once defined primarily by amyloid-β and tau aggregations, is now being explored for its complex interplay with immune processes, offering a deeper understanding of its development. This study delves into the dynamic relationship between the brain and the immune system, utilizing human samples from individuals predisposed to AD and various preclinical models. Our findings reveal that both environmental and genetic risk factors for AD significantly influence immune phenotypes and functions, which in turn impact disease progression. Further, we discovered that disrupting brain-spleen communication alters myeloid cell fate and cognitive performance in 5xFAD mice. These insights demonstrate the profound and reciprocal influence between the brain and the immune system. They underscore the importance of these interactions in understanding not only AD but also a wider array of neurological conditions, suggesting that this interplay is crucial for comprehending the complexities of such diseases. Zoom Link: https://weizmann.zoom.us/j/5420322495?pwd=ZmhUR0kxWTB6aDh0bklBNFlzV1JNdz09 Meeting ID: 542 032 2495 Password: 862769

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Disordered crystals as viewed by light scattering

Date:

23

Monday

October

2023

Colloquium

Time: 11:00-12:15

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Omer Yaffe

Organizer: Department of Chemical and Biological Physics

Disordered crystals as viewed by light scattering Colloquium website

Abstract: In materials science, there is a prevailing paradigm that single crystals are al ... Read more In materials science, there is a prevailing paradigm that single crystals are almost perfectly ordered, allowing their structure to be precisely represented as a unit cell, from which their electronic and mechanical properties can be derived. However, our research has uncovered that thermal motion disrupts this ideal representation in numerous materials, including halide perovskites, ion conductors, and organic semiconductors. In this talk, I will describe our journey to comprehend thermal motion in single crystals through Raman spectra. We investigate the discrepancies between experimental observations of light scattering and theoretical predictions and consider the coupling between vibrational modes. Furthermore, we explore how such coupling impacts the functional properties of these crystals.

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Gallery: Disordered crystals as viewed by light scattering Gallery

The Southern Lights — Rhodopsin Complexes Discovered in an Algae Near Antarctica Can Help Unravel the Secrets of the Brain

Date:

16

Monday

October

2023

Colloquium

Time: 11:00-12:15

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Moran Shalev-Benami

Organizer: Department of Chemical and Structural Biology

Gallery: The Southern Lights — Rhodopsin Complexes Discovered in an Algae Near Antarctica Can Help Unravel the Secrets of the Brain Gallery

Abstract: Rhodopsins are a ubiquitous family of light sensing/signaling proteins. In recen ... Read more Rhodopsins are a ubiquitous family of light sensing/signaling proteins. In recent work, our group discovered an intriguing family of rhodopsins in algae: the bestrhodopsins. Through cryo-EM and comprehensive biochemical and electrophysiological studies, we showed that bestrhodopsins are fusions of rhodopsins and ion channels which assemble as mega-complexes to enable light-controlled passage of ions across membranes. Regulation of a classical ion channel by an attached photoreceptor has never been found before in nature, and previous attempts to engineer light-regulated fused channels have yielded limited success. The discovery and characterization of bestrhodopsins thus provide a new template for designing proteins with light-sensing and ion-conducting activities, as well as represent a platform for regulating cellular signaling in living organisms using light. These findings are therefore not only important as a basic scientific discovery but also for the field of optogenetics where neural activity is controlled by light. In the present talk, I will present the discovery of the bestrhodopsins, and explain how we use our cryo-EM work for structure-based design of dramatically improved tools to manipulate signaling cascades in cells by light control, paving the way for the next generation of optogenetics tools to study brain function in vivo.

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The Southern Lights — Rhodopsin Complexes Discovered in an Algae Near Antarctica Can Help Unravel the Secrets of the Brain Colloquium website

Experience-dependent genetic and synaptic regulation of stability and plasticity in cortical circuits

Date:

28

Thursday

September

2023

Lecture / Seminar

Time: 11:00-12:15

Location: The David Lopatie Hall of Graduate Studies

Lecturer: Dahlia Kushinsky-Student Seminar PhD Thesis Defense

Organizer: Department of Brain Sciences

Details:

Abstract: Neural circuits in the brain must be plastic enough to allow an animal to adapt ... Read more Neural circuits in the brain must be plastic enough to allow an animal to adapt to and learn from new experiences yet they must also remain functionally stable such that previously learned skills and information are retained. Thus, fundamental questions in neuroscience concern the molecular, cellular, and circuit mechanisms that balance the plasticity and stability of neural circuits. During my studies, I investigated these mechanisms in three studies that focused on sensory- and behavioral state-dependent changes in transcription and GABAergic inhibition in the visual cortex of adult mice. In my Ph.D. defense, I will elaborate on the novel molecular-cellular mechanisms that I discovered in these studies and discuss their role in conveying both plasticity and stability to visual processing and perception.

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Effects of cocaine use on organization and dimensionality of neural representations in rat orbitofrontal cortex

Date:

18

Monday

September

2023

Lecture / Seminar

Time: 14:00-15:00

Location: Nella and Leon Benoziyo Building for Brain Research

Lecturer: Prof. Geoffrey Schoenbaum MD/PhD

Organizer: Department of Brain Sciences

Details: Room 113 Host:rony.paz@weizmann.ac.il For accessibility issues: naomi.mose ... Read more

Abstract: Substance use disorder can be partly understood as a failure to properly learn a ... Read more Substance use disorder can be partly understood as a failure to properly learn about or use information about consequences, particularly when they are rare, delayed, or even anecdotal. Such behaviors require access to cognitive models to allow estimation of likely outcomes, capabilities which depend critically on prefrontal and particularly orbitofrontal areas in rats, monkeys, and humans. We have previously shown that prior cocaine use disrupts performance in a variety of experimental settings that isolate orbitofrontal-dependent, inference-based behavior. In the current experiment, I will describe the effect of prior cocaine use on the organization of information by neural ensembles in rat orbitofrontal and prelimbic cortices during performance of a multi-dimensional choice task.

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Ph.D. Defense Seminar

Date:

04

Monday

September

2023

Lecture / Seminar

Time: 11:30-12:30

Title: The reasons behind better DNA preservation in the petrous bone: cellular and 3D structural analysis of modern pig and ancient human petrous bones

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Jamal Ibrahim

Organizer: Scientific Archeology Unit

Contact: jamal.ibrahim@weizmann.ac.il

Details: The seminar will be also via zoom: Meeting ID: 940 5265 6196 Meeting password: 449244

Understanding spontaneous neuronal activity with neurophotonics

Date:

30

Wednesday

August

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Anna Devor

Organizer: Department of Brain Sciences

Details: Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il For accessibility issues: ... Read more

Abstract: The last decade has seen a rapid advance of neurophotonic technologies, in large ... Read more The last decade has seen a rapid advance of neurophotonic technologies, in large part thanks to the BRAIN Initiative as well as other large-scale neuroscience projects in the US and around the world. We now have a large array of diverse experimental and computational tools to study the brain across species, scales, levels of description, in animals and humans. Notably, the lion’s share of these technologies falls under the general umbrella of neurophotonics. This lecture will focus on several microscopic neurophotonic technologies in the context of understanding spontaneous neuronal and neurovascular activity in the mouse cerebral cortex. Among these tools is optically transparent Windansee electrode arrays that can be combined with optical imaging. Combining Windansee recordings with two-photon imaging and biophysical modeling, we show that spontaneous inputs to layer 1 were coded by a selective, sparse sub-population of local neurons. This is in contrast with earlier studies in the same system where each instance of a sensory input activated a different subset of neurons indicating redundancy in coding. Because selective coding by a few “oracle” neurons is nonredundant, we are tempted to speculate that the health of internally generated brain activity may be more vulnerable to damage or disease compared to that in response to external stimuli. Light refreshments before the seminar

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The safety pharmacology of Syk inhibitors: Cardiovascular complications resulting from off-target tyrosine kinase inhibition

Date:

24

Monday

July

2023

Lecture / Seminar

Time: 14:00-15:00

Location: Max and Lillian Candiotty Building

Lecturer: Ms. Marieke Van Daele

Organizer: Dwek Institute for Cancer Therapy Research

Contact: michalav@weizmann.ac.il

Plant structure and motion as inspiration for bioinspired buildings and soft machines

Date:

18

Tuesday

July

2023

Lecture / Seminar

Time: 11:30-12:30

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Prof. Thomas Speck

Organizer: Department of Plant and Environmental Sciences

Contact: david.zeevi@weizmann.ac.il

Details: Host: Dr. David Zeevi

Tools & Techniques Seminar

Date:

18

Tuesday

July

2023

Lecture / Seminar

Time: 10:00-11:00

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Saar Ezagouri/Moshe Goldsmith/Elad Stolovicki

Organizer: Department of Biomolecular Sciences

Abstract: Saare - Circa-SCOPE: high-throughput live single -cell imaging method for analys ... Read more

Special Guest Seminar by Dr. Konstantin Feinberg

Date:

17

Monday

July

2023

Lecture / Seminar

Time: 13:00-14:00

Title: Schwann cells are key regulator of corneal epithelial renewal

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Dr. Konstantin Feinberg

Organizer: Department of Molecular Neuroscience

Contact: ronitrosenberg@weizmann.ac.il

Abstract: Purpose: Corneal sensory nerves protect the cornea from injury. They are also th ... Read more Purpose: Corneal sensory nerves protect the cornea from injury. They are also thought to stimulate limbal stem cells (LSCs) to produce transparent epithelial cells constantly, enabling vision. In other organs, Schwann cells (SCs) associated with tissue-innervating axon terminals mediate tissue regeneration. This study defines the critical role of the corneal axon-ensheathing SCs in homeostatic and regenerative corneal epithelial cell renewal. Methods: SC localization in the cornea was determined by in situ hybridization and immunohistochemistry with SC markers. In vivo SC visualization and/or ablation was performed in mice with inducible corneal SC-specific expression of TdTomato and/or Diphtheria toxin, respectively. The relative locations of SCs and LSCs was observed with immunohistochemical analysis of harvested genetically SC-pre-labeled mouse corneas with LSC-specific antibodies. The correlation between cornea-innervating axons and the appearance of SCs was ascertained using corneal denervation in rats. To determine the limbal niche cellular composition and gene expression changes associated with innervation-dependent epithelial renewal, single cell RNA sequencing (scRNA-Seq) of dissociated healthy, de-epithelized and enervated cornea limbi was performed. Results: We observed limbal enrichment of corneal axon-associated myelinating and non-myelinating SCs. Induced local genetic ablation of SCs, while leaving corneal sensory innervation intact, markedly inhibited corneal epithelial renewal. scRNA-seq analysis (i) highlighted the transcriptional heterogeneity of cells populating the limbal niche and (ii) identified transcriptional changes associated with corneal innervation and during wound healing that model potential regulatory paracrine interactions between SCs and LSCs. Conclusions: Limbal SCs are required for innervation-dependent corneal epithelial renewal.

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Vision and AI

Date:

16

Sunday

July

2023

Lecture / Seminar

Time: 12:15-13:15

Title: Deep Learning Approaches for Inverse Problems in Computational Imaging and Chemistry

Location: Jacob Ziskind Building

Lecturer: Tomer Weiss

Organizer: Department of Computer Science and Applied Mathematics

Abstract: In this talk, I will present two chapters from my Ph.D. thesis. The core of my r ... Read more In this talk, I will present two chapters from my Ph.D. thesis. The core of my research focuses on methods that utilize the power of modern neural networks not only for their conventional tasks such as prediction or reconstruction, but rather use the information they “learned” (usually in the forms of their gradients) in order to optimize some end-task, draw insight from the data, or even guide a generative model. The first part of the talk is dedicated to computational imaging and shows how to apply joint optimization of the forward and inverse models to improve the end performance. We demonstrate these methods on three different tasks in the fields of Magnetic Resonance Imaging (MRI) and Multiple Input Multiple Output (MIMO) radar imaging. In the second part, we show a novel method for molecular inverse design that utilizes the power of neural networks in order to propose molecules with desired properties. We developed a guided diffusion model that uses the gradients of a pre-trained prediction model to guide a pre-trained unconditional diffusion model toward the desired properties. This method allows, in general, to transform any unconditional diffusion model into a conditional generative model.

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Dendritic voltage imaging, excitability rules, and plasticity

Date:

10

Monday

July

2023

Lecture / Seminar

Time: 12:45-13:45

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Adam E. Cohen

Organizer: Department of Brain Sciences

Details: Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il For accessibilit ... Read more

Abstract: Membrane voltage in dendrites plays a key role in mediating synaptic integration ... Read more Membrane voltage in dendrites plays a key role in mediating synaptic integration and activity-dependent plasticity; but dendritic voltages have been difficult to measure. We developed molecular, optical, and computational tools for simultaneous optogenetic perturbations and voltage mapping in dendrites of neurons in acute slices and in awake mice. These experiments revealed relations between dendritic ion channel biophysics and rules of synaptic integration and plasticity. I will also describe tools for mapping large-scale network dynamics with millisecond time resolution, and for mapping brain-wide patterns of plasticity.

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Cancer Imaging in the Clinics

Date:

10

Monday

July

2023

Lecture / Seminar

Time: 12:15-13:00

Location: Wolfson Building for Biological Research

Lecturer: Prof. Dorith Shaham

Organizer: Life Sciences

Details: This lecture will be preceded by a lecture on “Cancer imaging Principles” ... Read more

Cancer Imaging Principles

Date:

10

Monday

July

2023

Lecture / Seminar

Time: 11:15-12:00

Location: Wolfson Building for Biological Research

Lecturer: Prof. Rachel Katz-Brull

Organizer: Life Sciences

Details: Within the FGS course on Translational Cancer Research Host. Zvi Livneh

Toward “reading” and “writing” neural population codes in the primate cortex

Date:

05

Wednesday

July

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Prof. Eyal Seidemann

Organizer: Department of Brain Sciences

Contact: devora.sofer@weizmann.ac.il

Details: host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il

Abstract: : A central goal of sensory neuroscience is to understand the nature of the neur ... Read more : A central goal of sensory neuroscience is to understand the nature of the neural code in sensory cortex to the point where we could “read” the code – i.e., account for a subject’s perceptual capabilities using solely the relevant cortical signals, and “write” the code – i.e., substitute sensory stimuli with direct cortical stimulation that is perceptually equivalent. Distributed representations and topography are two key properties of primate sensory cortex. For example, in primary visual cortex (V1), a localized stimulus activates millions of V1 neurons that are distributed over multiple mm2, and neurons that are similarly tuned are clustered together at the sub-mm scale and form several overlaid topographic maps. The distributed and topographic nature of V1’s representation raises the possibility that in some visual tasks, the neural code in V1 operates at the topographic scale rather than at the scale of single neurons. If this were the case, then the fundamental unit of information would be clusters of similarly tuned neurons (e.g., orientation columns), and to account for the subjects’ performance, it would be necessary and sufficient to consider the summed activity of the thousands of neurons within each cluster. A long-term goal of my lab is to test the topographic population code hypothesis. In this presentation, I will describe our progress toward developing a bi-directional, read-write, optical-genetic toolbox for directly testing this hypothesis in behaving macaques.

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Siah3 acts upstream to Parkin to limit mitophagy and facilitate the apoptotic machinery during axonal pruning

Date:

04

Tuesday

July

2023

Lecture / Seminar

Time: 10:00-11:00

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Omer Abraham

Organizer: Department of Biomolecular Sciences

Crosstalk between the ECM and Proteases from destruction to regeneration Conference website

Abstract: Spatial and temporal regulation of the apoptotic machinery is critical for the e ... Read more Spatial and temporal regulation of the apoptotic machinery is critical for the execution of multiple cellular events. Here we identify Seven In Absentia Homolog 3 (Siah3) as a new regulator of the cell death machinery during axonal pruning in developing mice. Sensory neurons from Siah3 KO mice exhibit delayed axonal degeneration and Caspase-3 activation in response to trophic deprivation. In agreement, the Siah3 KO mice display increased peripheral sensory innervation. Mechanistically, we show that Siah3 directly binds to the core mitophagy machinery protein Parkin, and, importantly, co-ablation of Prkn and Siah3 reverses the delay in axonal degeneration and Caspase-3 activation detected in Siah3 KO neurons. Strikingly, loss of Siah3 causes dramatic increase in axonal mitophagy upon trophic deprivation, suggesting that Siah3 is a positive regulator of axonal elimination acting by modulation of Parkin-mediated mitophagy. Overall, our results suggest that Parkin-mediated mitophagy restrains the apoptotic system by eliminating signaling mitochondria and reveal the role of mitochondrial signaling in axonal elimination.

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Physics Colloquium

Date:

22

Thursday

June

2023

Colloquium

Time: 11:15-12:30

Title: Seeking the Closest Habitable-Zone Planets

Location: Edna and K.B. Weissman Building of Physical Sciences

Lecturer: Prof. Suvrath Mahadevan

Organizer: Faculty of Physics

Contact: eti.shalem@weizmann.ac.il

Details: Coffee, Tea and more...

Abstract: The discovery of planets capable of hosting biosignatures, and the characterizat ... Read more The discovery of planets capable of hosting biosignatures, and the characterization of the atmospheres of these planets, is a key and achievable goal in our lifetime. These goals require some of the most demanding precision spectroscopic and photometric measurements. I will discuss the instrumental challenges of detecting such planets with the Doppler radial velocity technique, and the evolution of the design of these instruments as they seek ever-tighter control of environmental parameters, and increased measurement precision. A suite of new technologies like frequency stabilized laser combs, low drift etalons, and deeper understanding of the detectors is enabling a new level of precision in radial velocity measurements - as well as illustrating new challenges. I will then discuss how the stars themselves are the remaining challenge, as magnetically driven processes create ‘stellar activity’ noise that can masquerade as planets and obfuscate their detection, and I highlight a few paths to mitigate this, along with some of the latest scientific results from the HPF and NEID instruments. I will discuss one iteration of a possible future, weaving its way from now through JWST individual and mini-population studies of planet atmospheres, large population studies with missions like ARIEL, the near-future of RV surveys, detection and characterization prospects with large ground-based, and the challenges and opportunities with future imaging and spectroscopic missions like LUVOIR and LIFE. The goal of discovering and characterizing terrestrial mass planets capable of hosting liquid water on their surfaces may now be within reach! But true understanding of the origin and meaning of the biosignatures we detect will likely require transdisciplinary research across multiple fields.

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Crosstalk between the ECM and Proteases from destruction to regeneration

Date:

20

Tuesday

June

2023

-

22

Thursday

June

2023

Conference

Time: 08:00

Location: The David Lopatie Conference Centre

Contact: irit.sagi@weizmann.ac.il

Beyond the arcuate fasciculus: A multiplicity of language pathways in the human brain

Date:

13

Tuesday

June

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Michal Ben-Shachar

Organizer: Department of Brain Sciences

Contact: michal.ramot@weizmann.ac.il

Abstract: Early models of the neurobiology of language targeted a single white matter path ... Read more Early models of the neurobiology of language targeted a single white matter pathway, the left arcuate fasciculus, as the critical language pathway in the human brain. Current models, supported by structural and functional imaging data, describe a more elaborate scheme of semi-parallel and bilateral white matter pathways that implement a variety of linguistic processes. In this talk, I will describe our current understanding of the language connectome, and highlight some recent additions to this scheme, including the frontal aslant tract and cerebellar pathways. I will expand on the role of ventral language pathways in extracting word structure, and on the role of dorsal and cerebellar pathways in mediating speech fluency and written text production. Our experimental approach combines diffusion MRI and targeted behavioral measurements, relating specific aspects of language processing with structural tract properties assessed in the same individual. Our findings show that cognitive associations with tractometry generalize across independent samples, languages, modalities and tasks. I will discuss the implications of our findings in the context of dual stream models of spoken and written language processing.

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A link between viscoelastic mechanics and biochemical function of proteins

Date:

12

Monday

June

2023

Colloquium

Time: 11:00-12:15

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Tsvi Tlusty

Organizer: Faculty of Chemistry

A link between viscoelastic mechanics and biochemical function of proteins Colloquium website

Abstract: Our starting point is the idea that specific regions in the protein evolve to b ... Read more Our starting point is the idea that specific regions in the protein evolve to become flexible viscoelastic elements facilitating conformational changes associated with function, especially allostery. Simple theories show how these regions can emerge through evolution and indicate that they are easily identified by amino acid rearrangement upon binding (i.e., shear motion). Surprisingly, AlphaFold can also identify such regions by computing the shear induced by a single or a few mutations. With these methods, we have tested the concept of shear and its functional relevance in a variety of proteins. I will present recent results from an experimental study of the enzyme guanylate kinase linking shear, large scale motions, and catalytic function. Altogether, the present findings paint a physical picture of proteins as viscoelastic machines with sequence encoded specifications, and we will discuss its general implications for understanding proteins and designing new ones.

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Reprogramming the topology of the nociceptive circuit in C. elegans reshapes sexual behavior

Date:

12

Monday

June

2023

Lecture / Seminar

Time: 11:00-12:15

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Vladyslava Pechuk

Organizer: Department of Brain Sciences

Contact: devora.sofer@weizmann.ac.il

Details: Student Seminar Ph.D. Thesis Defense

Abstract: The effect of the detailed connectivity of a neural circuit on its function and ... Read more The effect of the detailed connectivity of a neural circuit on its function and the resulting behavior of the organism, is a key question in many neural systems Here, I study the circuit for nociception in C elegans which is composed of the same neurons in the two sexes, that are wired differently I set out to elucidate how the topological design of a compact neuronal circuit affects its behavioral output, how genetic sex affects the connectivity and dynamics of a circuit, and how specific circuit components orchestrate together to establish the behavioral sexual dimorphism I used behavioral assays, optogenetics calcium and glutamate imaging, measurement of protein expression, artificial connectivity, molecular and genetic tools, and show that the nociceptive sensory neurons respond similarly in the two sexes, yet the animals display sexually dimorphic behaviors to the same aversive stimuli To uncover the role of the downstream network topology in shaping behavior, I measured the neuronal activity of a key interneuron, and found dimorphic responses to the stimulus as well as dimorphic intrinsic basal interneuron activity I then showed that neuron specific genetic sex plays a role in shaping connectivity and circuit dynamics, and proceed to an artificial subtle synaptic rewiring which flips behavior between sexes Interestingly, when presented with aversive cues, rewired males were compromised in finding mating partners, suggesting that network topologies that enable efficient avoidance of noxious cues have a reproductive " My results present a deconstruction of the design of a neural circuit that controls sexual behavior, and how to reprogram it

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Vision and AI

Date:

08

Thursday

June

2023

Lecture / Seminar

Time: 12:15-13:15

Title: Imagic: Text-Based Real Image Editing with Diffusion Models

Location: Jacob Ziskind Building

Lecturer: Shiran Zada

Organizer: Department of Computer Science and Applied Mathematics

Abstract: Text-conditioned image editing has recently attracted considerable interest. How ... Read more Text-conditioned image editing has recently attracted considerable interest. However, most methods are currently either limited to specific editing types (e.g., object overlay, style transfer), or apply to synthetically generated images, or require multiple input images of a common object. In this paper we demonstrate, for the very first time, the ability to apply complex (e.g., non-rigid) text-guided semantic edits to a single real image. For example, we can change the posture and composition of one or multiple objects inside an image, while preserving its original characteristics. Our method can make a standing dog sit down or jump, cause a bird to spread its wings, etc. — each within its single high-resolution natural image provided by the user. Contrary to previous work, our proposed method requires only a single input image and a target text (the desired edit). It operates on real images, and does not require any additional inputs (such as image masks or additional views of the object). Our method, which we call "Imagic", leverages a pre-trained text-to-image diffusion model for this task. It produces a text embedding that aligns with both the input image and the target text, while fine-tuning the diffusion model to capture the image-specific appearance. We demonstrate the quality and versatility of our method on numerous inputs from various domains, showcasing a plethora of high quality complex semantic image edits, all within a single unified framework

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Local and long-range inputs contributing to sequence generation in the zebra finch

Date:

06

Tuesday

June

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Prof. Michael A. Long

Organizer: Department of Brain Sciences

Details: Host: Dr. Yarden Cohen Yarden.J.Cohen@weizmann.ac.il tel: 5138 For accessibi ... Read more

Abstract: : A central question in neuroscience is how local processing and long-range infl ... Read more : A central question in neuroscience is how local processing and long-range influences work together to create behaviorally relevant neural dynamics. We address this issue by examining the song control pathway in the zebra finch. We find sufficient synaptic information is present in a key cortical structure to enable propagation of song-related sequences. We further demonstrate that long-range inputs from the motor thalamus can engage this circuitry in the service of behavior and large-scale brain synchronization. Our findings suggest that thalamic inputs may play an important initiating role for behaviorally-relevant cortical activity across species.

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Chemical and Biological Physics Guest Seminar

Date:

06

Tuesday

June

2023

Lecture / Seminar

Time: 10:00-11:00

Title: Materials with a twist: atomically controlled interfaces for clean energy

Location: Perlman Chemical Sciences Building

Lecturer: Prof Magali Lingenfelder

Organizer: Department of Chemical and Biological Physics

Contact: ron.naaman@weizmann.ac.il

Abstract: Our society faces a critical challenge in shifting from a reliance on carbon-bas ... Read more Our society faces a critical challenge in shifting from a reliance on carbon-based energy to sustainable renewable sources. A key step towards achieving clean energy lies in developing efficient catalysts that can convert chemical energy into electricity or use electrons to generate chemical energy. In our research group, we tackle these challenges by creating customized materials that draw inspiration from nature (biomimicry) and combine principles from interfacial chemistry and surface physics. For this presentation, I focus on the process of photosynthesis as inspiration for the design, characterization, and dynamic nature of functional interfaces that drive energy conversion processes such as CO2 electroreduction and water splitting. I will also discuss the application of cutting-edge scanning probe microscopy, which allows us to visualize dynamic electrochemical processes at the nanoscale (operando imaging). Additionally, I will highlight our use of unconventional strategies that leverage chiral molecules and abundant two-dimensional materials to enhance electrocatalytic conversion processes. (References : Nanoletters, 2021, 21, 2059; Nature Comm., 2022, 13, 3356, IJC 62, 11, 2022).

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Volatile cortical working memory representations crystalize with practice

Date:

01

Thursday

June

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Prof. Peyman Golshani

Organizer: Department of Brain Sciences

Details: Host-Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il For accessibility issues: n ... Read more

Abstract: Working memory (WM), the process through which information is transiently mainta ... Read more Working memory (WM), the process through which information is transiently maintained and manipulated over a brief period of time, is essential for most cognitive functions. However, the mechanisms underlying the generation and stability of WM neuronal representations at the population level remain elusive. To uncover these mechanisms, we trained head-fixed mice to perform an olfactory working memory task and used optogenetics to delineate circuits causal for behavioral performance. We used mesoscopic and light bead two photon imaging to record from up to 35,000 secondary motor cortical neurons simulataneously across multiple days and show differential stabilization of different task parameters with learning and practice of the task. We find that cortical working memory representations causal for task performance are highly volatile but only stabilize after multiple days of practice well after task learning. We hypothesize that representational drift soon after learning may allow for higher levels of flexibility for new task rules. I will also review some of the new open-source tools developed for large-scale imaging of neural activity patterns in freely behaving animals.

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Vision and AI

Date:

01

Thursday

June

2023

Lecture / Seminar

Time: 12:15-13:15

Title: Spaceborne multi-view computational tomography (CT)

Location: Jacob Ziskind Building

Lecturer: Yoav Schechner

Organizer: Department of Computer Science and Applied Mathematics

Abstract: We describe new computer vision tasks stemming from upcoming multiview tomograph ... Read more We describe new computer vision tasks stemming from upcoming multiview tomography from space. Solutions involve both novel imaging hardware and computational algorithms, based on machine learning and differential rendering. This can transform climate research and medical X-ray CT. The key idea is that advanced computing can enable computed tomography of volumetric scenes, based scattered radiation. We describe an upcoming space mission (CloudCT, funded by the ERC). It has 10 nano-satellites that will fly in an unprecedented formation, to capture the same scene (cloud fields) from multiple views simultaneously, using special cameras. The satellites and cameras are built now. They - and the algorithms - are specified to meet computer vision tasks, including geometric and polarimetric self-calibration in orbit, and estimation of 3D volumetric distribution of matter and microphysical properties. Deep learning and differential rendering enable analysis to scale to big data downlinked from orbit. Core ideas are generalized for medical X-ray imaging, to enable significant reduction of dose and acquisition time, while extracting chemical properties per voxel. The creativity of the computer vision and graphics communities can assist in critical needs for society, and this talk points out relevant challenges.

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Cognitive neuroscience of learning and memory in human infants

Date:

30

Tuesday

May

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Nick Turk-Browne

Organizer: Department of Brain Sciences

Details: Host- Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues: ... Read more

Abstract: In this talk, I will present the approach my lab has developed for performing fM ... Read more In this talk, I will present the approach my lab has developed for performing fMRI studies in awake infants during cognitive tasks. I will share some of our recent studies and highlight some of the big open questions that remain to be addressed, with potential to reveal the brain systems underlying how infants perceive and attend to their environment, why infants are such proficient learners, and why we all have amnesia for infant experiences. Despite countless limitations and challenges at present, this work suggests that awake infant fMRI could become more feasible, useful, and ubiquitous in cognitive neuroscience.

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In-Vivo Imaging Technologies for Pre-Clinical Research

Date:

24

Wednesday

May

2023

Lecture / Seminar

Time: 13:00-14:00

Title: Spotlight on Science series

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Inbal Biton

Contact: ayelet.vilan@weizmann.ac.il

Machine Learning and Statistics Seminar

Date:

24

Wednesday

May

2023

Lecture / Seminar

Time: 11:15-12:30

Title: Cycle-edge message passing for group and non-group synchronization

Location: Jacob Ziskind Building

Lecturer: Prof. Gilad Lerman

Organizer: Department of Computer Science and Applied Mathematics

Abstract: The general synchronization problem asks to recover states of objects from their ... Read more The general synchronization problem asks to recover states of objects from their corrupted relative measurements. When the states are represented by group elements (e.g. 3-D rotations or permutations) this problem is known as group synchronization. In several applications, the algebraic structure of the states is more complicated, for example, the states can be represented by partial permutations. The synchronization problem has many applications, in particular, to structure-from-motion (SfM), where one needs to estimate the 3D structure of a scene from a set of its projected 2D images. I will first describe a general framework for group synchronization, the Cycle-Edge Message Passing (CEMP), and then explain its generalization to non groups, by exemplifying the case of partial permutation synchronization. I will emphasize mathematical difficulties, review some mathematical guarantees for the proposed methods and also demonstrate an application. This is a joint work with Shaohan Li and Yunpeng Shi.

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Exploring sex-specific regulation of aging and health

Date:

23

Tuesday

May

2023

Lecture / Seminar

Time: 10:00-11:00

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Dr. Itamar Harel

Organizer: Department of Biomolecular Sciences

Abstract: Bio: Experimental biology of vertebrate aging and age-related diseases: http://h ... Read more Bio: Experimental biology of vertebrate aging and age-related diseases: http://harel-lab.com/ Itamar Harel received his PhD in developmental biology at the Weizmann Institute of Science, and then trained in aging research at Stanford University. In 2018 he joined the Department of Genetics at the Hebrew University as Assistant Professor. The Harel lab is exploring fundamental questions in aging biology, such as why is aging such a strong driver of disease? To address a major challenge in aging research, Itamar has developed a comprehensive genetic platform for rapid exploration of aging and disease in a naturally short-lived vertebrate. The findings by the Harel lab have clinical implications for developing new strategies for modeling and treating age-related diseases, and for developing pro-longevity interventions.

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Ultrafast processes and the challenge of decoherence

Date:

22

Monday

May

2023

Colloquium

Time: 11:00-12:15

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Eberhard K. U. Gross

Organizer: Faculty of Chemistry

Ultrafast processes and the challenge of decoherence Colloquium website

Abstract: A prominent goal of present-day condensed-matter physics is the design of electr ... Read more A prominent goal of present-day condensed-matter physics is the design of electronic devices with ever faster switching times. As an example I will present the optically induced spin transfer between magnetic sublattices, the so-called OISTR effect, which allows the switching of magnetic textures on the scale of a femto-second or less. This effect was first predicted with real-time TDDFT and later confirmed in many experiments. To create from this effect a real-world device on has to face the problem of decoherence, i.e. the phenomenon that quantum systems tend to lose their quantumness due to interactions with the environment. For electrons, the principal source of decoherence is the non-adiabatic interaction with nuclear degrees of freedom, i.e. with an “environment” that cannot be removed. In fact, the paradigm of electronic-structure theory where electrons move in the static Coulomb potential of clamped nuclei, while useful in the ground state, is an idealization hardly ever satisfied in dynamical processes. Non-adiabaticity, i.e. effects of the coupled motion of electrons and nuclei beyond the Born-Oppenheimer approximation are found everywhere. In this lecture, the exact factorization will be presented as a universal approach to understand and, ultimately, control non-adiabatic effects, in particular decoherence, from an ab-initio perspective.

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Gallery: Ultrafast processes and the challenge of decoherence Gallery

“ Programmatic and Deep Learning Analysis Pipelines for 4D-STEM Materials Science Experiments”

Date:

21

Sunday

May

2023

Lecture / Seminar

Time: 11:00-12:00

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Colin Ophus

Organizer: Department of Molecular Chemistry and Materials Science

New Frontiers in Cardiac and Vascular Biology Conference website

Abstract: Scanning transmission electron microscopy (STEM) is one of the most popular mate ... Read more Scanning transmission electron microscopy (STEM) is one of the most popular materials science methods to characterize the structure and chemistry of nanoscale samples, owing to its high resolution and many flexible operating modes. In a conventional STEM experiment, we focus the electron beam down to a probe from nanometer to sub-angstrom scale, and scan it over the sample surface while recording diffracted signals which are transmitted through the specimen. STEM can also record analytic signals such as x-rays generated by the electron beam to measure composition, or energy loss of the transmitted electrons to probe the electronic structure of samples. Conventional STEM imaging detectors experiments produce only a few intensity values at each probe position, but modern high-speed detectors allow us to measure a full 2D diffraction pattern, over a grid of 2D probe positions, forming a four dimensional (4D)-STEM dataset. These 4D-STEM datasets record information about the local phase, orientation, deformation, and other parameters, for both crystalline and amorphous materials. 4D-STEM datasets can contain millions of images and therefore require highly automated and robust software codes to extract the target properties. In this talk, I will introduce our open source py4DSTEM analysis toolkit, and show how we use these codes to perform data-intensive studies of material properties over functional length scales. I will also demonstrate some applications of modern machine learning tools, to perform measurements on electron diffraction patterns where property signals have been scrambled by multiple scattering of the electron beam.

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New Frontiers in Cardiac and Vascular Biology

Date:

20

Saturday

May

2023

-

24

Wednesday

May

2023

Conference

Time: 08:00

Location: The David Lopatie Conference Centre

Organizer: The M.D. Moross Institute for Cancer Research,The Dimitris N. Chorafas Institute for Scientific Exchange

Contact: karina.yaniv@weizmann.ac.il

Non-invasive Methods for Extracting Microstructural Information from Human Tissues: Implementation in a Clinical MRI Scanner

Date:

18

Thursday

May

2023

Lecture / Seminar

Time: 09:30-10:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr Analía Zwick

Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy

Abstract: Extracting quantitative information about tissue microstructure using non-invasi ... Read more Extracting quantitative information about tissue microstructure using non-invasive methods is an exceptional challenge in understanding disease mechanisms and enabling early diagnosis of pathologies. Magnetic Resonance Imaging (MRI) is a promising and widely used technique to achieve this goal, but it still provides low resolution to reveal details of the microstructure. Recently, we have developed methods to produce images with quantitative information about the microstructure based on selective probing of spin dephasing induced by molecular diffusion restriction in cavities of the tissue microstructure [1-3]. The feasibility of the theoretical method has been demonstrated so far by first-principles experiments and simulations on typical size distributions of white matter in the mouse brain [3]. As a next step towards practical implementation, we have implemented this method in clinical scanners [4]. In this work, I present the challenges and preliminary results of this implementation in both phantoms and human volunteers. These results open up a new avenue for MRI to advance in extracting quantitative, and fast microstructural information from images. [1] A. Zwick, D. Sueter, G. Kurizki, G. A. Álvarez, Phys. Rev. Applied 14, 024088, (2020). [2] M. Capiglioni, A. Zwick, P. Jiménez, G. A. Álvarez. Proc. Intl. Soc. Mag. Reson. Med. 29, 2036 (2021) [3] M. Capiglioni, A. Zwick, P. Jiménez and G. A. Álvarez, Phys. Rev. Applied 15, 014045 (2021). [4] E. Saidman, A. Zwick, S. Tambalo, T. Feiweier, J. Jovicich, G. A. Álvarez. Proc. Intl. Soc. Mag. Reson. Med. (2023)

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Vision and AI

Date:

11

Thursday

May

2023

Lecture / Seminar

Time: 12:15-13:15

Title: Human Motion Diffusion Model

Lecturer: Guy Tevet

Organizer: Department of Computer Science and Applied Mathematics

Abstract: Natural and expressive human motion generation is the holy grail of computer ani ... Read more Natural and expressive human motion generation is the holy grail of computer animation. It is a challenging task, due to the diversity of possible motion, human perceptual sensitivity to it, and the difficulty of accurately describing it. Therefore, current generative solutions are either low-quality or limited in expressiveness. Diffusion models, which have already shown remarkable generative capabilities in other domains, are promising candidates for human motion due to their many-to-many nature, but they tend to be resource hungry and hard to control. In this paper, we introduce Motion Diffusion Model (MDM), a carefully adapted classifier-free diffusion-based generative model for the human motion domain. MDM is transformer-based, combining insights from motion generation literature. A notable design-choice is the prediction of the sample, rather than the noise, in each diffusion step. This facilitates the use of established geometric losses on the locations and velocities of the motion, such as the foot contact loss. As we demonstrate, MDM is a generic approach, enabling different modes of conditioning, and different generation tasks. We show that our model is trained with lightweight resources and yet achieves state-of-the-art results on leading benchmarks for text-to-motion and action-to-motion.

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Smell and our unconscious sense of self

Date:

10

Wednesday

May

2023

Lecture / Seminar

Time: 13:00-14:00

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Prof. Benjamin D. Young

Organizer: Department of Brain Sciences

Abstract: Benjamin D. Young Ph.D. is an associate professor in philosophy and interdiscipl ... Read more Benjamin D. Young Ph.D. is an associate professor in philosophy and interdisciplinary neuroscience at the University of Nevada, Reno. Previously he held a Kreitman Post-Doctoral Fellowship in the Department of Brain and Cognitive Sciences at Ben-Gurion University, as well as Visiting Assistant Professorship and Post-Doctoral Fellowship in the Department of Cognitive Science at Hebrew University. He conducts empirically informed philosophical research with a particular emphasis on olfaction focusing on non-conceptual content, qualitative consciousness in the absence of awareness, and the perceptible objects of smell. His most recent projects include co-editing the textbook Mind, Cognition, and Neuroscience and the collection Theoretical Perspectives on Smell. Ben is finishing a book on smell tentatively titled Stinking Philosophy! and beginning to work on a book about the unconscious mind. Previously he showed how olfaction calls into question the general neuroscientific theories of consciousness and the relationship between access and phenomenal consciousness. Dr. Young’s current research extends this framework and examines the role that smell plays in allowing us to recognize our embodied material composition and what we can perceive about others from their smell both with and without subjective awareness. For more information about Ben’s research see https://www.unr.edu/philosophy/faculty-staff/benjamin-young

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The unique life of the intrinsically disordered proteins (IDPs)

Date:

09

Tuesday

May

2023

Lecture / Seminar

Time: 10:00-11:00

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Prof. Yosef Shaul

Organizer: Department of Biomolecular Sciences

Abstract: Over 20% of our proteins are intrinsically disordered (IDP/IDR). IDPs/IDRs regul ... Read more Over 20% of our proteins are intrinsically disordered (IDP/IDR). IDPs/IDRs regulate many aspects of the living cells. They are generally highly dynamic, modifiable, adaptable, and short-lived proteins. We have previously reported that IDPs/IDRs undergoing proteasomal degradation via 26S and 20S proteasomes, the latter in a ubiquitin-independent manner. In this seminar, I will show data on the mechanisms of their 20S-mediated degradation in vitro and in the cells. Using proteomic approaches, we have identified many IDPs/IDRs undergoing 20S proteasomal degradation, all bearing unique structural features shared by liquid-liquid phase separation (LLPS) proteins. Proteasomal live imaging further highlighted the intracellular proteasomal dynamics and LLPS formation.

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Nature, nurture, and the neuroscience of parenthood

Date:

02

Tuesday

May

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Bianca Jones Marlin

Organizer: Department of Brain Sciences

Details: Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il tel: 6957 For accessibil ... Read more

Abstract: Introduction: Bianca Jones Marlin, Ph.D. is a neuroscientist and Herbert and Flo ... Read more Introduction: Bianca Jones Marlin, Ph.D. is a neuroscientist and Herbert and Florence Irving Assistant Professor of Cell Research at the Zuckerman Institute at Columbia University in New York City. Her research investigates how organisms unlock innate behaviors at appropriate times, and how learned information is passed to subsequent generations via transgenerational epigenetic inheritance. Dr. Marlin combines neural imaging, behavior, and molecular genetics to uncover how learned behavior in the parent can become innate behavior in the offspring— work that promises to make a profound impact on societal brain health, mental well-being, and parenting. For more information about Dr. Marlin, visit www.biancajonesmarlin.com

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Nature, nurture, and the neuroscience of parenthood

Date:

02

Tuesday

May

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Bianca Jones Marlin

Organizer: Department of Brain Sciences

Details: Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il tel: 6957 For accessibil ... Read more

Abstract: Introduction: Bianca Jones Marlin, Ph.D. is a neuroscientist and Herbert and Flo ... Read more Introduction: Bianca Jones Marlin, Ph.D. is a neuroscientist and Herbert and Florence Irving Assistant Professor of Cell Research at the Zuckerman Institute at Columbia University in New York City. Her research investigates how organisms unlock innate behaviors at appropriate times, and how learned information is passed to subsequent generations via transgenerational epigenetic inheritance. Dr. Marlin combines neural imaging, behavior, and molecular genetics to uncover how learned behavior in the parent can become innate behavior in the offspring— work that promises to make a profound impact on societal brain health, mental well-being, and parenting. For more information about Dr. Marlin, visit www.biancajonesmarlin.com

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Vision and AI

Date:

20

Thursday

April

2023

Lecture / Seminar

Time: 12:15-13:15

Title: Training Set Reconstruction and Single-Video Generation

Location: Jacob Ziskind Building

Lecturer: Niv Haim

Organizer: Department of Computer Science and Applied Mathematics

Neurotechnology 2023: Precision Approaches for Studying and Treating the Brain Conference website

Abstract: Over the past decade, deep learning has made significant strides in the fields o ... Read more Over the past decade, deep learning has made significant strides in the fields of computer vision and machine learning. However, there is still a lack of understanding regarding how these machines store and utilize training samples to generalize to unseen data. In my thesis (guided by Prof. Irani), I investigated how neural networks encode training samples in their parameters and how such samples can sometimes be reconstructed. Additionally, I examined the capabilities of generative models in learning and generalizing from a single video. Specifically, I explored the effectiveness of patch-based methods and diffusion models in generating diverse output samples, and how such models can utilize the motion and dynamics of a single input video to learn and generalize.

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Neurotechnology 2023: Precision Approaches for Studying and Treating the Brain

Date:

19

Wednesday

April

2023

-

20

Thursday

April

2023

Conference

Time: 08:00 - 20:30

Location: The David Lopatie Conference Centre

Contact: takashi.kawashima@weizmann.ac.il

Navigation in larval zebrafish:strategies and internal representations

Date:

03

Monday

April

2023

Lecture / Seminar

Time: 12:45-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Ruben Portugues

Organizer: Department of Brain Sciences

Details: Host: Takashi Kawashima takashi.kawashima@weizmann.ac.il For accessibility is ... Read more

Abstract: Larval zebrafish can navigate their environment and seek conditions that meet th ... Read more Larval zebrafish can navigate their environment and seek conditions that meet their physiological needs. We refer to this process as homeostatic navigation. We use careful behavioral analysis, whole-brain imaging, and neuronal perturbations to identify the behavioral strategy and the neuronal circuitry that underlie this important behavior. In addition, I will recap recent studies from our lab, involving perceptual decision making and the identification of a heading direction network, that all together, provide insights into how the brain of this small vertebrate controls behavior across these various paradigms.

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3D quantitative-amplified Magnetic Resonance Imaging (3D q-aMRI)

Date:

02

Sunday

April

2023

Lecture / Seminar

Time: 16:30-17:30

Location: Perlman Chemical Sciences Building

Lecturer: Itamar Terem

Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy

Brain plasticity Regulation and Modulation. Neurobiology symposium in honor of Prof. Menahem Segal Conference website

Abstract: Changes in blood vessel pulsation and cerebrospinal fluid dynamics cause cyclic ... Read more Changes in blood vessel pulsation and cerebrospinal fluid dynamics cause cyclic deformation of the brain, which can be altered by neurological pathologies. Various MRI techniques are available to visualize and quantify pulsatile brain motion, but they have limitations. Amplified MRI (aMRI) is a promising new technique that can visualize pulsatile brain tissue motion by amplifying sub-voxel motion in cine MRI data, but it lacks the ability to quantify the sub-voxel motion field in physical units. Here a novel 3D quantitative aMRI (3D q-aMRI) post-processing algorithm is introduced that can visualize and quantify pulsatile brain motion. To validate the algorithm, we tested it on a 3D digital phantom and on healthy volunteers. We also acquired preliminary data on participants with Alzheimer's disease and healthy aging controls. The results show that 3D q-aMRI can accurately quantify sub-voxel motion (of 0.005 pixel size) and has potential diagnostic value in identifying disease-induced biomechanical differences.

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Brain plasticity Regulation and Modulation. Neurobiology symposium in honor of Prof. Menahem Segal

Date:

29

Wednesday

March

2023

-

30

Thursday

March

2023

Conference

Time: 15:00 - 17:15

Location: The David Lopatie Conference Centre

Contact: ofer.yizhar@weizmann.ac.il

The neurobiological function of experience-regulated genomic enhancers From transcriptional mechanisms to control over synaptic plasticity and sensory processing

Date:

20

Monday

March

2023

Lecture / Seminar

Time: 14:45-15:45

Location: Max and Lillian Candiotty Building

Lecturer: Ori Roethler Dr. Ivo Spiegel Lab

Organizer: Department of Brain Sciences

Details:

Abstract: The brain consists of a mosaic of distinct cell-types with unique activity-regul ... Read more The brain consists of a mosaic of distinct cell-types with unique activity-regulated gene programs that can drive long-lasting changes in the function and structure of developing and matured neural circuits. However, the molecular mechanisms in specific neuronal subtypes underlying these cellular/circuit changes remain poorly understood and techniques for studying these molecular mechanisms in specific cell populations are still lacking. Genomic enhancers are thought to modulate specific sets of synapses by regulating experience-induced and cell-type specific transcription of genes that promote neural circuit plasticity. Nevertheless, this idea remains untested. Thus, here I set out to investigate the genomic mechanisms that control the experience-induced transcription of the Insulin-like growth factor 1 (Igf1) in disinhibitory VIP interneurons (INs) in the adult visual cortex and the cellular and circuit functions they underly. I found two cell-type specific sensory-induced enhancers that selectively drive sensory-induced Igf1 transcription. These enhancers homeostatically control the ratio between excitation and inhibition (E/I-ratio), thereby restricting the activity of VIP INs and preserving the response properties to visual stimuli.

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Animal morphogenesis as a dynamical phase transition

Date:

20

Monday

March

2023

Colloquium

Time: 11:00-12:15

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Erez Braun

Organizer: Faculty of Chemistry

Animal morphogenesis as a dynamical phase transition Colloquium website

Abstract: A remarkable hallmark of animal morphogenesis is the convergence of this dynamic ... Read more A remarkable hallmark of animal morphogenesis is the convergence of this dynamic process into a stereotypic viable organism. The current picture relies on biochemical patterning with a well-defined hierarchy of forward-driven processes. I will discuss the nature of developmental processes, arguing that morphogenesis is robust due to the synergistic dynamics of mechanical, biochemical and electrical processes. Hydra regeneration provides a unique experimental setup, allowing us to develop a physics framework for this pattern-formation process. We demonstrate that an external electric field can be tuned to drive morphogenesis in whole-body Hydra regeneration, backward and forward, around a critical point in a controlled manner. We show that calcium (Ca2+) fluctuations underlie Hydra morphogenesis. Utilizing an external electric field as a control, we study these fluctuations at the onset of morphogenesis showing their universal characteristics and their associations with the morphological dynamics. Our analysis shows that the Hydra's tissue resides near the onset of bistability and the external control modulates the dynamics near that onset. It paints a picture of morphogenesis analogous to a dynamical phase transition.

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Gallery: Animal morphogenesis as a dynamical phase transition Gallery

Neuronal activity and noise in synaptic wiring specificity

Date:

16

Thursday

March

2023

Lecture / Seminar

Time: 10:30-13:30

Location: Nella and Leon Benoziyo Building for Brain Research

Lecturer: Dr. Laura Andreae

Organizer: Department of Brain Sciences

Details: ROOM 113 Host: Dr. Yoav Livneh yoav.livneh@weizmann.ac.il For accessibility ... Read more

Abstract: The role of neuronal activity in the development of neurons and circuits remains ... Read more The role of neuronal activity in the development of neurons and circuits remains controversial. Historically, activity has been seen to be critical for the sculpting of connectivity patterns after the period of synapse formation, often pruning unused synapses and helping to maintain or grow active ones. We now have evidence that a specific type of activity, spontaneous transmitter release, in the past often regarded as simply 'noise', plays a role in synapse formation and the development of dendritic morphology at early stages in the developmental period. Using both in vitro and in vivo approaches in mice to manipulate spontaneous transmitter release and the postsynaptic receptors that detect it, we show that these effects are connection specific in the developing hippocampal circuit. Many of the key synaptic proteins involved are known to be mutated in severe neurodevelopmental disorders, indicating how important these early roles may be in healthy brain development.

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Special seminar: Simultaneous Imaging of millions of Single cells with the Xenium In situ platform

Date:

14

Tuesday

March

2023

Lecture / Seminar

Time: 10:00-11:00

Location: Max and Lillian Candiotty Building

Lecturer: Dr. Stephen Hague

Organizer: Department of Life Sciences Core Facilities

Contact: hadas.keren-shaul@weizmann.ac.il

Spatiotemporal Resolution of Conformational Changes in Biomolecules by Pulsed Electron-Electron Double Resonance Spectroscopy

Date:

09

Thursday

March

2023

Lecture / Seminar

Time: 09:30-10:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Tobias Hett

Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy

Abstract: Proteins are highly dynamic biomolecules that can undergo ligand-induced confor ... Read more Proteins are highly dynamic biomolecules that can undergo ligand-induced conformational changes, thus often playing a crucial role in biomolecular processes. For an in-depth understanding of protein function, the conversion of one conformational state into another has to be resolved over space and time. Pulsed electron-electron double resonance spectroscopy (PELDOR/DEER) in combination with site-directed spin labelling (SDSL) is a powerful tool for obtaining distributions of interspin distances in proteins [1, 2]. It allows for measurements with Angstrom precision, but it cannot directly determine the time scale and the mechanism of the conformational change. However, coupling PELDOR with rapid freeze-quench techniques adds the time axis to the distance distribution and thus permits studying conformational changes with temporal resolution. Here, we show that the combination of Microsecond Freeze-Hyperquenching (MHQ) [3] and PELDOR resolves ligand-triggered conformational changes in proteins on the Angstrom length and microsecond time scale. It allows taking snapshots along the trajectory of the conformational change by rapid quenching within aging times of 82-668 μs, and it is applicable at protein amounts down to 7.5 nmol (75 μM, 100 μL) per time point. We applied MHQ/PELDOR to the cyclic nucleotide-binding domain (CNBD) of the MloK1 channel from Mesorhizobium loti, which undergoes a conformational change upon binding of cyclic adenosine monophosphate (cAMP). We observed a gradual population shift from the apo to the holo state on the microsecond time scale, but no distinct conformational intermediates (Fig. 1a, b). [4] Figure 1: a) Interspin distance distributions obtained at different aging times and b) the corresponding fractions of apo and holo state. c) Free-energy profile of the ligand-induced conformational change. Corroborated by measurements of ligand-binding kinetics and molecular dynamics (MD) simulations, we interpret the data in terms of a dwell time distribution. The transitions across the free-energy barriers (Fig. 1c) i.e., ligand binding and the conformational change, are on the nanosecond time scale and thus below the time resolution of the MHQ device. However, the dwell time of the apo state in complex with the cAMP ligand is in the microsecond range and can be monitored by MHQ/PELDOR. [4] Literature: [1] A.D. Milov et al., Fiz. Tverd. Tela 1981, 23, 975-982. [2] G. Jeschke, Annu. Rev. Phys. Chem. 2012, 63, 419-446. [3] A.V. Cherepanov et al., Biochim. Biophys. Acta 2004, 1656, 1-31. [4] T. Hett et al., J. Am. Chem. Soc. 2021, 143, 6981-6989.

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"Uncovering novel Cardiac Biochemistry from large human cohort studies"

Date:

05

Sunday

March

2023

Lecture / Seminar

Time: 09:30-10:30

Location: Nella and Leon Benoziyo Building for Biological Sciences

Lecturer: Dr. Michael Elgart

Organizer: Department of Biomolecular Sciences

Abstract: "Mechanistic studies of human disease-related biochemistry typically rely on ani ... Read more "Mechanistic studies of human disease-related biochemistry typically rely on animal models to devise hypotheses and conduct functional testing. The success of this approach is conditioned on conservation of biochemical pathways between humans and the animal, and the ability of the model to recapitulate key features of human disease which is rare . This is rarely true for complex human conditions such as neurological and cardiovascular diseases. In the absence of a suitable animal model, the study of human diseases has been limited to analysis of associations between clinical outcomes and physiological and/or molecular traits. Using the recent availability of multi-dimensional data from very large human cohorts we have devised principally novel approaches to identify associations of biochemicals with existing biochemical pathways in the context of human disease. This new ability allowed us to formulate a new paradigm akin to Koch postulates but applied to mechanistic component identification of complex disease. It relies on identification of putative disease drivers from human data, verification of these findings in animal models, deriving novel mechanism-related associations from the animal model, and back-testing the new associations in human data. This workflow is much more likely to correctly reflect shared biology between the animal model and humans as it pertains to disease, and thus serve as a true tool for mechanistic biochemical research."

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Optical Imaging and image quantification across scales

Date:

02

Thursday

March

2023

Lecture / Seminar

Time: 09:00-10:00

Location: Max and Lillian Candiotty Building

Lecturer: Dr. Sefi Addadi

Organizer: Department of Life Sciences Core Facilities

Contact: yoseph.addadi@weizmann.ac.il

Horizontal cells of the vertebrate retina – From channels to functions

Date:

28

Tuesday

February

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Andreas Feigenspan

Organizer: Department of Brain Sciences

Abstract: Visual information is transferred at the ribbon synapse – the first synapse of ... Read more Visual information is transferred at the ribbon synapse – the first synapse of the visual system – from photoreceptors to bipolar cells and horizontal cells. Whereas multiple bipolar cell types form parallel channels of vertical signal transfer to ganglion cells, the output neurons of the retina, the molecular basis of horizontal function within the retinal circuitry remains enigmatic. We have combined electrophysiology and calcium imaging with immunocytochemistry as well as single-cell RNA-sequencing and machine-learning approaches to establish a detailed map of voltage- and ligand-gated ion channels expressed by horizontal cells of the vertebrate retina. Our results provide a characteristic molecular signature of ionotropic glutamate receptors responsible for converting photoreceptor signals into postsynaptic membrane potential changes. We suggest that local information processing in horizontal cell dendrites is accompanied by cell-wide signals mediated by activation of voltage-gated calcium and sodium channels, which generate spike-like events. Comparison across different vertebrate species indicates a common theme of ion channel expression with variations based on evolutionary distance. Correlating the spatio-temporal pattern of horizontal cell activity with the biophysical properties of ion channels and neurotransmitter receptors will provide a better understanding of early signal processing in the vertebrate retina.

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Sensory processing in the whisker system of awake, behaving mice

Date:

27

Monday

February

2023

Lecture / Seminar

Time: 14:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Rasmus Petersen

Organizer: Department of Brain Sciences

Details: Host: Prof. Ehud Ahissar ehud.ahissar@weizmann.ac.il For accessibility issues ... Read more

Abstract: The ultimate purpose of sensory systems is to drive behaviour. Yet the bulk of ... Read more The ultimate purpose of sensory systems is to drive behaviour. Yet the bulk of textbook knowledge of sensory systems comes from experiments on anaesthetised animals where the motor systems are disengaged. The broad aim of our research is to investigate the neural basis of sensation in the behaving brain. In this talk, I will present work that addresses two fundamental issues concerning the function of primary sensory cortex. First, what role does Sensory Adaptation play under awake, behaving conditions? Second, to what extent does behaviour modulate sensory processing in freely moving animals?

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How the brain transforms sensory input into action

Date:

21

Tuesday

February

2023

Lecture / Seminar

Time: 12:30-13:30

Lecturer: Prof. Tom Mrsic-Flogel

Organizer: Department of Brain Sciences

Details: Zoom link: https://weizmann.zoom.us/j/96661197731?pwd=QTM4dHcvUFovTjZRU1BUVGhnW ... Read more

Sensitizing P-selectin-expressing brain malignancies to immune checkpoint modulators

Date:

16

Thursday

February

2023

Lecture / Seminar

Time: 14:00-15:00

Location: Max and Lillian Candiotty Building

Lecturer: Prof. Ronit Satchi-Fainaro, PhD

Organizer: Dwek Institute for Cancer Therapy Research

Contact: michal.av@weizmann.ac.il

Details: https://weizmann.zoom.us/j/5065402023?pwd=a3Z6KzRCU0xJaUFoM2Y5emZwZm1oZz09

Special Guest Seminar

Date:

16

Thursday

February

2023

Lecture / Seminar

Time: 10:00-11:00

Title: Inter-organelle communication pathways revealed by imaging

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Prof. Jennifer Lippincott-Schwartz

Organizer: Department of Molecular Genetics

Contact: evi.ben-ami@weizmnn.ac.il

Molecular MRI of brain function

Date:

16

Thursday

February

2023

Lecture / Seminar

Time: 09:30-10:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Alan Jasanoff

Organizer: The Helen and Martin Kimmel Institute for Magnetic Resonance Research

Contact: ananaamat@gmail.com

Abstract: Understanding the neural bases of behavior and cognition requires determining ho ... Read more Understanding the neural bases of behavior and cognition requires determining how mechanistically distinct processing elements combine to carry out brain function at an integrated level. In this talk, I will introduce some of our laboratory’s efforts to address this goal using a combination of molecular sensors with noninvasive wide-field imaging. In the first part of the talk, I will discuss how workhorse optical neuroimaging approaches have inspired the design of molecular MRI probes for sensing physiological variables. Some of these probes detect light, providing a means for deep-tissue MRI-assisted optical imaging. I will next introduce an alternative molecular imaging concept inspired by widely used hemodynamic functional MRI techniques. By reengineering some of the proteins and peptides involved in neurovascular coupling, it is possible to create sensitive probes for a variety of neurobiological targets. I will illustrate how this strategy can be used to elucidate patterns of information flow and neurochemically specific functional connectivity in brain circuitry, with anticipated utility for deciphering mechanisms of learning and sensory processing in rodents and primates.

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Cerebral Cortex Connectomics

Date:

14

Tuesday

February

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Moritz Helmstaedter

Organizer: Department of Brain Sciences

Details: Host: Prof. Yaniv Ziv yaniv.ziv@weizmann.ac.il For accessibility issues:naomi ... Read more

Abstract: Dept of Connectomics Max Planck Institute for Brain Research Frankfurt ... Read more

Understanding nutritional impact on bone development and quality

Date:

12

Sunday

February

2023

Lecture / Seminar

Time: 15:00-16:00

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Prof. Efrat Monsonego Ornan

Organizer: Life Sciences

Contact: yael.kuperman@weizmann.ac.il

Mapping brainstem nuclei structure and connectivity in health and disease

Date:

07

Tuesday

February

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Marta Bianciardi

Organizer: Department of Brain Sciences

Details: Host: Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues c ... Read more

Abstract: Brainstem nuclei in humans play a crucial role in vital functions, such as arous ... Read more Brainstem nuclei in humans play a crucial role in vital functions, such as arousal, autonomic homeostasis, sensory and motor relay, nociception, and sleep and have been implicated in a vast array of brain pathologies, including disorders of consciousness, sleep disorders, autonomic disorders, pain, Parkinson’s disease and other motor disorders. Yet, an in vivo delineation of most human brainstem nuclei location and connectivity using conventional imaging has been elusive because of limited sensitivity and contrast for detecting these small regions using standard neuroimaging methods. In this talk, Dr. Bianciardi will present the probabilistic atlas and connectome of 31 brainstem nuclei of the arousal, motor, autonomic and sensory systems developed by her team in healthy living humans using structural, functional and diffusion-based MRI at 7 Tesla. She will also show the translatability of 7 Tesla connectivity results to conventional 3 Tesla imaging. Dr Bianciardi will conclude her seminar by presenting the first translational application of the brainstem nuclei atlas to investigate arousal and motor mechanisms in traumatic coma and premanifest synucleinopathy.

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Faculty Seminar

Date:

02

Thursday

February

2023

Lecture / Seminar

Time: 12:45-14:00

Title: Computational Imaging for Scientific Discovery: From Cloud Physics to Black Holes Dynamics

Location: Jacob Ziskind Building

Lecturer: Aviad Levis

Organizer: Department of Computer Science and Applied Mathematics

Details: Imaging plays a key role in advancing science, from revealing the internal struc ... Read more Imaging plays a key role in advancing science, from revealing the internal structure of clouds to providing the first visual evidence of a black hole. While both examples come from different imaging systems, they illustrate what can be achieved with modern computational approaches. Computational imaging combines concepts from physics, machine learning, and signal processing to reveal hidden structures at the smallest and largest of scales. In this talk, I will highlight how peeling away layers of the underlying physics leads to a spectrum of algorithms targeting new scientific discoveries. I will focus on the Event Horizon Telescope (EHT), a unique computational camera with the goal of imaging the glowing fluid surrounding supermassive black holes. In May of 2022, the EHT collaboration revealed the first images of the black hole at the center of our galaxy: Sagittarius A* (Sgr A*). These images were computationally reconstructed from measurements taken by synchronized telescopes around the globe. While images certainly offer interesting insights, looking toward the future, we are developing new computational algorithms that aim to go beyond a 2D image. For example, could we use EHT observations to recover the dynamic evolution or even the 3D structure? We tackle these challenges by integrating emerging AI concepts with physics models. Our hope is that in the not-too-distant future, these new and exciting prospects will enable scientific discovery and even provide a glimpse into the very nature of space-time itself in our galaxy's most extreme environment. Bio: Aviad Levis is a postdoctoral scholar in the Department of Computing and Mathematics at Caltech, working with Prof. Katherine Bouman. Currently, as part of the Event Horizon Telescope collaboration, his work focuses on developing novel computational methods for imaging black hole dynamics. Prior to that, he received his Ph.D. (2020) from the Technion and his B.Sc. (2013) from Ben-Gurion University. Notably, his Ph.D. research into 3D remote sensing of clouds is a key enabler in a novel interdisciplinary space mission (CloudCT) funded by the ERC and led by Yoav Schechner, Ilan Koren, and Klaus Schilling. Aviad is a recipient of the Zuckerman and the Viterbi postdoctoral fellowships.

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Abstract: Imaging plays a key role in advancing science, from revealing the internal struc ... Read more Imaging plays a key role in advancing science, from revealing the internal structure of clouds to providing the first visual evidence of a black hole. While both examples come from different imaging systems, they illustrate what can be achieved with modern computational approaches. Computational imaging combines concepts from physics, machine learning, and signal processing to reveal hidden structures at the smallest and largest of scales. In this talk, I will highlight how peeling away layers of the underlying physics leads to a spectrum of algorithms targeting new scientific discoveries. I will focus on the Event Horizon Telescope (EHT), a unique computational camera with the goal of imaging the glowing fluid surrounding supermassive black holes. In May of 2022, the EHT collaboration revealed the first images of the black hole at the center of our galaxy: Sagittarius A* (Sgr A*). These images were computationally reconstructed from measurements taken by synchronized telescopes around the globe. While images certainly offer interesting insights, looking toward the future, we are developing new computational algorithms that aim to go beyond a 2D image. For example, could we use EHT observations to recover the dynamic evolution or even the 3D structure? We tackle these challenges by integrating emerging AI concepts with physics models. Our hope is that in the not-too-distant future, these new and exciting prospects will enable scientific discovery and even provide a glimpse into the very nature of space-time itself in our galaxy's most extreme environment. // Bio: Aviad Levis is a postdoctoral scholar in the Department of Computing and Mathematics at Caltech, working with Prof. Katherine Bouman. Currently, as part of the Event Horizon Telescope collaboration, his work focuses on developing novel computational methods for imaging black hole dynamics. Prior to that, he received his Ph.D. (2020) from the Technion and his B.Sc. (2013) from Ben-Gurion University. Notably, his Ph.D. research into 3D remote sensing of clouds is a key enabler in a novel interdisciplinary space mission (CloudCT) funded by the ERC and led by Yoav Schechner, Ilan Koren, and Klaus Schilling. Aviad is a recipient of the Zuckerman and the Viterbi postdoctoral fellowships.

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My adventures in the rat interactive foraging facility (RIFF)

Date:

31

Tuesday

January

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Eli Nelken

Organizer: Department of Brain Sciences

Details: Host-Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues:na ... Read more

Abstract: We developed an arena (called colloquially the RIFF) for jointly studying behavi ... Read more We developed an arena (called colloquially the RIFF) for jointly studying behavior and neural activity in freely-behaving rats. The RIFF operates as a state machine, allowing us to implement a large number of different behaviors as Markov Decision Processes and therefore to analyze much of the data within the theoretical framework of reinforcement learning. In the studies I will show here, we recorded neural activity from auditory cortex while rats performed auditory-guided behavior. We observed an intricate interplay between behavior and neural activity that was much richer than we expected.

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"Molecules in a Quantum-Optical Flask"

Date:

25

Wednesday

January

2023

Lecture / Seminar

Time: 11:00-12:00

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Tal Schwartz

Organizer: Department of Molecular Chemistry and Materials Science

Abstract: "Molecules in a Quantum-Optical Flask" When confined to small dimensions, the ... Read more "Molecules in a Quantum-Optical Flask" When confined to small dimensions, the interaction between light and matter can be enhanced up to the point where it overcomes all the incoherent, dissipative processes. In this "strong coupling" regime the photons and the material start to behave as a single entity, having its own quantum states and energy levels. In this talk I will discuss how such cavity-QED effects can be used in order to control material properties and molecular processes. This includes, for example, modifying photochemical reactions [1], enhancing excitonic transport up to ballistic motion close to the light-speed [2-3] and potentially tailoring the mesoscopic properties of organic crystals, by hybridizing intermolecular vibrations with electromagnetic THz fields [4-5]. 1. J. A. Hutchison, T. Schwartz, C. Genet, E. Devaux, and T. W. Ebbesen, "Modifying Chemical Landscapes by Coupling to Vacuum Fields," Angew. Chemie Int. Ed. 51, 1592 (2012). 2. G. G. Rozenman, K. Akulov, A. Golombek, and T. Schwartz, "Long-Range Transport of Organic Exciton-Polaritons Revealed by Ultrafast Microscopy," ACS Photonics 5, 105 (2018). 3. M. Balasubrahmaniyam, A. Simkovich, A. Golombek, G. Ankonina, and T. Schwartz, "Unveiling the mixed nature of polaritonic transport: From enhanced diffusion to ballistic motion approaching the speed of light," arXiv:2205.06683 (2022). 4. R. Damari, O. Weinberg, D. Krotkov, N. Demina, K. Akulov, A. Golombek, T. Schwartz, and S. Fleischer, "Strong coupling of collective intermolecular vibrations in organic materials at terahertz frequencies," Nat. Commun. 10, 3248 (2019). 5. M. Kaeek, R. Damari, M. Roth, S. Fleischer, and T. Schwartz, "Strong Coupling in a Self-Coupled Terahertz Photonic Crystal," ACS Photonics 8, 1881 (2021).

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Naturalistic approaches for studying social interactions, communication and language at cellular scale

Date:

24

Tuesday

January

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Ziv Williams

Organizer: Department of Brain Sciences

Details: Host-Dr. Michal Ramot michal.ramot@weizmann.ac.il Contact for accessibility i ... Read more

Abstract: Social interactions are remarkably dynamic, requiring individuals to understand ... Read more Social interactions are remarkably dynamic, requiring individuals to understand not only how their behavior may affect others but also how others may respond in return. In humans, social interactions are also often dominated by processes such as language and theory of mind which allow us to communicate complex thoughts and beliefs. Understanding the basic cellular processes that underlie social behavior or by which individuals communicate, however, has remained a challenge. Here, I describe naturalistic approaches developed in animals and humans that aim of investigating these questions. First, by developing an ethologically based group task in three-interacting rhesus macaques, I describe representations of other’s behavior by neurons in the prefrontal cortex, reflecting the other’s identities, their interactions, actions, and outcomes. I also show how these cells collectively represent the interaction between specific group members and how they enable mutually beneficial social behavior. Second, by recording from neurons in the human prefrontal cortex during language-based tasks, I describe neurons that reliably encode information about others’ beliefs across richly varying scenarios and that distinguish self- from other-belief-related representations. By further following their encoding dynamics, I also describe how these cells represent the contents of the others’ beliefs and predict whether they are true or false. Finally, I describe how these cell ensembles track linguistic information during natural speech processing and how language can be used to ask specific questions about the single-cellular constructs that underlie social reasoning. Together, these studies reveal cellular mechanisms for interactive social behavior in animals and humans and highlight the prospective use of naturalistic approaches in social neuroscience.

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Chemical and Biological Physics Guest Seminar

Date:

22

Sunday

January

2023

Lecture / Seminar

Time: 12:00

Title: How crystals flow – plastic deformation of colloidal single crystals

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr Ilya Svetlizky

Organizer: Department of Chemical and Biological Physics

Contact: lucio.frydman@weizmann.ac.il

Abstract: Plastic (irreversible) deformation of crystals requires disrupting the crystalli ... Read more Plastic (irreversible) deformation of crystals requires disrupting the crystalline order, which happens through nucleation and motion of topological line defects called dislocations. Interactions between dislocations lead to the formation of complex networks that, in turn, dictate the mechanical response of the crystal. The severe difficulty in atomic systems to simultaneously resolve the emerging macroscopic deformation and the evolution of these networks impedes our understanding of crystal plasticity. To circumvent this difficulty, we explore crystal plasticity by using colloidal crystals; the micrometer size of the particles allows us to visualize the deformation process in real-time and on the single particle level. In this talk, I will focus on two classical problems: instability of epitaxial growth and strain hardening of single crystals. In direct analogy to epitaxially grown atomic thin films, we show that colloidal crystals grown on mismatched templates to a critical thickness relax the imposed strain by nucleation of dislocations. Our experiments reveal how interactions between dislocations lead to an unexpectedly sharp relaxation process. I will then show that colloidal crystals can be strain-hardened by plastic shear; the yield strength increases with the dislocation density in excellent accord with the classical Taylor equation, originally developed for atomic crystals. Our experiments reveal the underlying mechanism for Taylor hardening and the conditions under which this mechanism fails.

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Rapid learning (and unlearning) in the human brain

Date:

19

Thursday

January

2023

Lecture / Seminar

Time: 14:00-15:00

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Nitzan Censor

Organizer: Department of Brain Sciences

Details: Host: Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues c ... Read more

Abstract: A plethora of studies have pointed to sensory plasticity in the adult visual sys ... Read more A plethora of studies have pointed to sensory plasticity in the adult visual system, documenting long-term improvements in perception. Such perceptual learning is enabled by repeated practice, inducing use-dependent plasticity in early visual areas and their readouts. I will discuss results from our lab challenging the fundamental assumption in low-level perceptual learning that only 'practice makes perfect', indicating that brief reactivations of visual memories induce efficient rapid perceptual learning. Utilizing behavioral psychophysics, brain stimulation and neuroimaging, we aim to reveal the neurobehavioral mechanisms by which brief exposure to learned information modulates brain plasticity and supports rapid learning processes. In parallel, we investigate how these learning mechanisms operate across domains, for example by testing the hypothesis that similar inherent mechanisms may also result in maladaptive consequences, when brief reactivations occur spontaneously as intrusive enhanced memories following negative events. Unraveling the mechanisms of this new form of rapid learning could set the foundations to enhance learning in daily life when beneficial, and to downregulate maladaptive consequences of negative memories.

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Brain-body interactions: sensations and predictions in the insular cortex

Date:

15

Sunday

January

2023

Lecture / Seminar

Time: 15:00-16:00

Location: Arthur and Rochelle Belfer Building for Biomedical Research

Lecturer: Dr. Yoav Livneh

Organizer: Life Sciences

Contact: yael.kuperman@weizmann.ac.il

Physics Colloquium

Date:

12

Thursday

January

2023

Colloquium

Time: 11:15-12:30

Title: How crystals flow - plastic deformation of colloidal single crystals

Location: Edna and K.B. Weissman Building of Physical Sciences

Lecturer: Ilya Svetlizky

Organizer: Faculty of Physics

Contact: eti.shalem@weizmann.ac.il

Abstract: Plastic (irreversible) deformation of crystals requires disrupting the crystalli ... Read more Plastic (irreversible) deformation of crystals requires disrupting the crystalline order, which happens through nucleation and motion of topological line defects called dislocations. Interactions between dislocations lead to the formation of complex networks that, in turn, dictate the mechanical response of the crystal. The severe difficulty in atomic systems to simultaneously resolve the emerging macroscopic deformation and the evolution of these networks impedes our understanding of crystal plasticity. To circumvent this difficulty, we explore crystal plasticity by using colloidal crystals; the micrometer size of the particles allows us to visualize the deformation process in real-time and on the single particle level. In this talk, I will focus on two classical problems: instability of epitaxial growth and strain hardening of single crystals. In direct analogy to epitaxially grown atomic thin films, we show that colloidal crystals grown on mismatched templates to a critical thickness relax the imposed strain by nucleation of dislocations. Our experiments reveal how interactions between dislocations lead to an unexpectedly sharp relaxation process. I will then show that colloidal crystals can be strain-hardened by plastic shear; the yield strength increases with the dislocation density in excellent accord with the classical Taylor equation, originally developed for atomic crystals. Our experiments reveal the underlying mechanism for Taylor hardening and the conditions under which this mechanism fails.

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“Functional MRI Advances at the Nexus of Acquisition, Processing, and Neuroscience”

Date:

12

Thursday

January

2023

Lecture / Seminar

Time: 09:30-10:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Prof. Peter Bandettini

Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy

Abstract: MRI is truly unique in that contrast and acquisition can be manipulated to highl ... Read more MRI is truly unique in that contrast and acquisition can be manipulated to highlight a many tissues and physiologic processes at a wide range of speeds and resolutions. In the early 90’s, echo-planar imaging (EPI), a rapid imaging method that required specialized hardware, enabled time series acquisition of images - each collected in tens of milliseconds. Susceptibility contrast weighting sensitized the images to subtle shifts in blood oxygenation, allowing localized brain activation changes in oxygenation to be observed in near real time, thus introducing fMRI to the world. Since this breakthrough, fMRI has continued to advance in sophistication and impact. Higher fields, higher performance gradients, and novel pulse sequences and contrasts have allowed ever more subtle effects to be observed at higher fidelity, speed, and resolution. The signal became more informative as brain activation paradigms and processing methods advanced in conjunction with our deeper understanding of artifact and signal. Importantly, our insight into brain structure and function motivated and informed the experiments and, likewise, was enriched by the results. In this talk, I’ll trace the progress in fMRI, showing how the creative tension between advances in technology, processing, and our understanding of brain activation dynamics and physiology generated many of the innovations. My talk will include retinotopy, event-related fMRI, multi-echo EPI, resting state fMRI, connectivity, representational similarity analysis, decoding, naturalistic stimuli, inter-subject correlation, high field, and layer fMRI. Lastly, I’ll describe some of the technical and practical challenges facing the field today.

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Capturing Neuronal Activity with more Precision and Fidelity in Time and Space

Date:

10

Tuesday

January

2023

Lecture / Seminar

Time: 12:30-13:30

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Peter Bandettini

Organizer: Department of Brain Sciences

Details: Host - Dr. Michal Ramot michal.ramot@weizmann.ac.il

Abstract: My lab’s focus in recent years has been split between development of ultra-hig ... Read more My lab’s focus in recent years has been split between development of ultra-high resolution fMRI at high field and the exploration of more sensitive yet robust methods to find all the salient transients and trends in the signal. High field, high resolution fMRI relies heavily on the acquisition technology and the functional contrast used as well as unique processing approaches that segment, as well as possible, cortical layers for analysis. Our fMRI time series analysis research relies on creative paradigm design in conjunction with tailored processing methods that strike a balance between casting a wide net for potentially informative signals and applying just enough modeling to make sense of the data. Our goal is to use fMRI to see neuronal activity and capture neural correlates of behavior that have previously been elusive to more standard approaches. Specifically, for our high resolution fMRI work, I will describe experiments demonstrating layer-specific activity in motor, somatosensory, and visual cortex that changes with tasks that modulate the hypothesized input and output cortical communication. In our lab, we perform layer fMRI using a functional contrast called VASO (vascular space occupancy) that is sensitive to blood volume changes in micro vessels - having more specificity than BOLD with only a small tradeoff in sensitivity. Layer fMRI has the potential to provide cortical hierarchy information and communication directionality based on the understanding that feedforward connections terminate predominantly in middle layers and feedback connections terminate in predominantly upper and lower layers. Hence by determining activation location across cortical depth, one can infer whether the activation is feedforward or feedback. I will also demonstrate how the use of resting state connectivity in conjunction with layer fMRI is able to discern such cortical hierarchy in visual areas. Lastly, I will also show examples of applications of layer fMRI in frontal cortex during a working memory task. In addition, I will show our high resolution fMRI work that has allowed us to discern a new digit organizational pattern in motor cortex. For our time series work, I will show our recent results in using connectivity-based decoding for identifying, in an unsupervised manner, tasks being performed. In addition, I will show an application of naturalistic stimuli and inter subject correlation to characterize personality trait and language skills of individuals. Lastly, changes arousal state during scanning has been viewed as both a confound and opportunity. I demonstrate our effort to further characterize the temporal and spatial signatures of arousal state changes in fMRI time series.

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Graphullerene: a new form of two-dimensional carbon

Date:

02

Monday

January

2023

Lecture / Seminar

Time: 11:00-12:00

Location: Gerhard M.J. Schmidt Lecture Hall

Lecturer: Dr. Elena Meirzadeh

Organizer: Department of Molecular Chemistry and Materials Science