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  • Date:16WednesdayJanuary 2019

    Machine Learning and Statistics Seminar

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    Time
    11:15 - 12:15
    Title
    Semiparametric Wavelet-based JPEG IV Estimator for Endogenously Truncated Data
    Location
    Jacob Ziskind Building
    Room 1
    Lecturer
    Nir Billfeld
    Haifa University
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar, Department of Computer Science and Applied Mathematics
    Faculty of Mathematical Sciences Seminar, Department of Mathematics
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of We show that when data are endogenously truncated the widely...»
    We show that when data are endogenously truncated the widely-used IV fails to render the relationship causal as well as introduces bias into the exogenous covariates. We offer a newly-introduced semiparametric biorthogonal wavelet-based JPEG IV estimator and its associated symmetry preserving kernel, which is closely related to object recognition methods in Artificial Intelligence. The newly-introduced enriched JPEG algorithm is a denoising tool amenable for identifying redundancies in a sequence of irregular noisy data points which also accommodates a reference-free criterion function for optimal denoising. This is suitable for situations where the original data distribution is unobservable such as in the case of endogenous truncation. This estimator corrects both biases, the one generated by endogenous truncation and the one generated by endogenous covariates, by means of denoising. We introduce a multifocal variant of the local GMM (MFGMM) estimator to establish jointly the entire parameter set asymptotic properties. Using Monte Carlo simulations attest to very high accuracy of our offered semiparametric JPEG IV estimator as well as high efficiency as reflected by root n consistency. These results have emerged from utilizing 2,000,000 different distribution functions, generating 100 million realizations to construct the various data sets.
    Lecture
  • Date:16WednesdayJanuary 2019

    Special Guest Seminar with Dr. Shai Carmi

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    Time
    11:30
    Location
    Arthur and Rochelle Belfer Building for Biomedical Research
    Botnar Auditorium
    Lecturer
    Dr. Shai Carmi
    Organizer
    Department of Molecular Genetics
    Contact
    AbstractShow full text abstract about In this talk, I will review recent work by myself and others...»
    In this talk, I will review recent work by myself and others on Jewish population and medical genetics, focusing on Ashkenazi Jews (AJ). I will describe the mixture events of AJ in Europe, the founder event they have experienced in the late Middle Ages, and their connections to ancient populations of the Levant. I will then describe large-scale genomic databases that we have recently generated for AJ, and the opportunities they open in medical genetics given the unique AJ demographic history. I will describe a few medical genetics projects including carrier screening, genome-wide association studies of microbiome composition and other traits, and preimplantation genetic diagnosis.
    Lecture
  • Date:17ThursdayJanuary 2019

    Special Guest Seminar with Ariel Schwartz

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    Time
    10:00
    Title
    “Deep Semantic Genome and Protein Representation for Annotation, Discovery, and Engineering”
    Location
    Arthur and Rochelle Belfer Building for Biomedical Research
    Botnar Auditorium
    Lecturer
    Dr. Ariel Schwartz
    Co-founder and Chief Technology Officer at Denovium Inc
    Organizer
    Department of Molecular Genetics
    Guest Lecture
    Contact
    AbstractShow full text abstract about Computational assignment of function to proteins with no kno...»
    Computational assignment of function to proteins with no known homologs is still an unsolved problem. We have created a novel, function-based approach to protein annotation and discovery called D-SPACE (Deep Semantic Protein Annotation Classification and Exploration), comprised of a multi-task, multi-label deep neural network trained on over 70 million proteins. Distinct from homology and motif-based methods, D-SPACE encodes proteins in high-dimensional representations (embeddings), allowing the accurate assignment of over 180,000 labels for 13 distinct tasks. The embedding representation enables fast searches for functionally related proteins, including homologs undetectable by traditional approaches. D-SPACE annotates all 109 million proteins in UniProt in under 35 hours on a single computer and searches the entirety of these in seconds. D-SPACE further quantifies the relative functional effect of mutations, facilitating rapid in-silico mutagenesis for protein engineering applications. D-SPACE incorporates protein annotation, search, and other exploratory efforts into a single cohesive model. We have recently extended this work from protein to DNA, enabling assignment of function to whole genomes and metagenomic contigs in seconds. Conserved genomic motifs as well as the functional impact of mutations in coding as well as non-coding genomic regions can be predicted directly from raw DNA sequence without the use of traditional comparative genomics approaches for motif detection, such as multiple sequence alignments, PSSMs, and profile HMMs.
    Lecture
  • Date:17ThursdayJanuary 2019

    Using solution NMR spectroscopy to characterise the dynamics of side chains and ions in proteins

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    Time
    10:00 - 11:00
    Location
    Perlman Chemical Sciences Building
    Room 404
    Lecturer
    Prof. Flemming Hansen
    Institute of Structural & Molecular Biology, University College London
    Organizer
    Department of Materials and Interfaces
    The Helen and Martin Kimmel Institute for Magnetic Resonance
    Contact
    AbstractShow full text abstract about Proteins are dynamic entities and function is often related ...»
    Proteins are dynamic entities and function is often related to motions on time-scales from picoseconds to seconds. Understanding not only the backbone, but also the dynamics and interactions of side chains and ions within proteins is crucial, because side chains cover protein surfaces and are imperative for substrate recognition and both side chains and ions are key for most active sites in enzymes.
    New NMR-based methods, anchored in 13C-direct-detection, to characterise the motions and interactions of functional side chains in large proteins will be presented. One class of experiments is aimed at arginine side chains and allows the strength of interactions formed via the guanidinium group to be quantified. NMR measurements of the solvent exchange rate of labile guanidinium protons as well as measurements of the rotational motion about the Nε-Cζ bond allows for such quantifications. Secondly, a new class of NMR experiments is presented, which relies on 13C-13C correlation spectra and allows a general quantification of motion and structure of side chains in large proteins. The new 13C-13C correlation spectra are applied to a 82 kDa protein, where well-resolved spectra with minimal overlap are obtained within a few hours.
    NMR-based methods to characterise potassium binding in medium-large proteins will also be presented. Due to its size, 15N-ammonium can be used as a proxy for potassium to probe potassium binding in medium-large proteins. NMR pulse sequences will be presented to select specific spin density matrix elements of the 15NH4+ spin system and to measure their relaxation rates in order to characterise the rotational correlation time of protein-bound 15NH4+ as well as report on chemical exchange events of the 15NH4+ ion.
    Lecture
  • Date:17ThursdayJanuary 2019

    Imaging Topological Materials

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    Time
    11:15 - 12:30
    Location
    Edna and K.B. Weissman Building of Physical Sciences
    Auditorium
    Lecturer
    Prof. Jenny Hoffman
    Harvard
    Organizer
    Faculty of Physics
    Contact
    DetailsShow full text description of 11:00 – coffee, tea, and more...»
    11:00 – coffee, tea, and more
    AbstractShow full text abstract about Today’s electronic technology – the pixels on the screen and...»
    Today’s electronic technology – the pixels on the screen and the process to print the words on the page – are all made possible by the controlled motion of an electron’s charge. In the last decade, the discovery of topological band insulators with robust spin-polarized surface states has launched a new subfield of physics promising a new paradigm in computing. When topology is combined with strong electron correlations, even more interesting states of matter can arise, suggesting additional applications in quantum computing. Here we present the first direct proof of a strongly correlated topological insulator. Using scanning tunneling microscopy to probe the real and momentum space structure of SmB6, we quantify the opening of a Kondo insulating gap. Within that gap, we discover linearly dispersing surface states with the heaviest observed Dirac states in any material – hundreds of times the mass of a free electron. We show how single atom defects can scatter these surface states, which paves the way towards manipulating single atoms and thus controlling surface states and their excitations at the nanoscale.
    Colloquia
  • Date:17ThursdayJanuary 2019

    Special Guest Seminar with Dan Bracha

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    Time
    12:00 - 13:00
    Title
    “Optogenetic Protein Droplets: Mapping and Moving Through Intracellular Phase Space”
    Location
    Arthur and Rochelle Belfer Building for Biomedical Research
    Botnar Auditorium
    Lecturer
    Dan Bracha
    Department of Chemistry and Biological Engineering, Princeton University, USA
    Organizer
    Department of Molecular Genetics
    Special Guest Seminar
    Contact
    Lecture
  • Date:17ThursdayJanuary 2019

    What can phytoliths and other proxies reveal about anthropogenic soils and the first sedentary societies of pre-Columbian Amazonia?

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    Time
    13:00
    Location
    Helen and Martin Kimmel Center for Archaeological Science
    Seminar Room
    Lecturer
    Dr. Jennifer Watling
    Laboratório de Arqueologia dos Trópicos, Museu de Arqueologia e Etnologia Laboratório de Micropaleontologia, Instituto de Geociências Universidade de São Paulo
    Organizer
    Academic Educational Research
    The Scientific Archaeology Unit
    Contact
    Lecture
  • Date:17ThursdayJanuary 2019

    Geometric Functional Analysis and Probability Seminar

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    Time
    13:30 - 15:30
    Title
    Optimization of random polynomials on the sphere in the full-RSB regime
    Location
    Jacob Ziskind Building
    Room 155
    Lecturer
    Eliran Subag
    Courant
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar, Department of Computer Science and Applied Mathematics
    Faculty of Mathematical Sciences Seminar, Department of Mathematics
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of To compute the spectral norm of a p-tensor one needs to opti...»
    To compute the spectral norm of a p-tensor one needs to optimize a homogeneous polynomial of degree p over the sphere. When p=2 (the matrix case) it is algorithmically easy, but for p
    Lecture
  • Date:17ThursdayJanuary 2019

    SHIRAT HAMADA

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    Time
    19:30 - 21:30
    Location
    Dolfi and Lola Ebner Auditorium
    Contact
    Lecture
  • Date:20SundayJanuary 2019

    TBA

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    Time
    11:00
    Location
    Sussman Family Building for Environmental Sciences
    M. Magaritz Seminar Room
    Lecturer
    Caryn Erlick-Haspel
    The Hebrew University, Jerusalem
    Organizer
    Department of Earth and Planetary Sciences
    Contact
    Lecture
  • Date:20SundayJanuary 2019

    On the mechanics of leaves, flowers, and sea-slugs

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    Time
    13:00
    Location
    Edna and K.B. Weissman Building of Physical Sciences
    Drory Auditorium
    Lecturer
    Shankar Venkataramani
    Shankar Venkataramani University of Arizona.
    Organizer
    Department of Physics of Complex Systems
    Contact
    AbstractShow full text abstract about I will discuss some connections between the geometry and the...»
    I will discuss some connections between the geometry and the mechanics of thin elastic objects with negative curvature. I will motivate the need for new "geometric" methods for discretizing the relevant equations, and present some of our preliminary work in this direction.

    This is joint work with Toby Shearman and Ken Yamamoto.


    Lecture
  • Date:21MondayJanuary 2019

    "Molecular electronics as a playground for nanoscale thermal transport"

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    Time
    11:00 - 12:15
    Location
    Dolfi and Lola Ebner Auditorium
    Lecturer
    Prof. Juan Carlos Cuevas
    Theoretical Condensed Matter Physics Department, Universidad Autónoma de Madrid, Spain
    Organizer
    Faculty of Chemistry
    Contact
    AbstractShow full text abstract about Abstract With the advent of novel fabrication techniques...»
    Abstract

    With the advent of novel fabrication techniques in the 1980s and 1990s, it became possible to explore many physical phenomena at the nanoscale. Since then, a lot of progress has been done in the understanding of the electronic transport, mechanical, and optical properties of nanoscale devices. However, thermal transport in these systems has remained relatively unexplored because of the experimental difficulty to measure the flow of heat and energy at this small scale. In this talk, I will review our theoretical and experimental efforts to establish the fundamental laws that govern nanoscale thermal transport by using atomic and molecular junctions as a playground. In particular, I will discuss basic phenomena such as Joule heating and Peltier cooling in molecular junctions [1,2] and quantized thermal transport in atomic-size contacts [3].

    References

    [1] W. Lee, K. Kim, W. Jeong, L.A. Zotti, F. Pauly, J.C. Cuevas, P. Reddy, Nature 498, 209 (2013).
    [2] L. Cui, R. Miao, K. Wang, D. Thompson, L.A. Zotti, J.C. Cuevas, E. Meyhofer, P. Reddy, Nature Nanotechnology 13, 122 (2018).
    [3] L. Cui, W. Jeong, S. Hur, M. Matt, J.C Klöckner, F. Pauly, J.C. Cuevas, E. Meyhofer, P. Reddy, Science 355, 1192 (2017).
    Colloquia
  • Date:21MondayJanuary 2019

    IMM Guest seminar-Prof. Yoram Reiter will lecture on "Engineering Immune Effector Molecules and Cells for Immunotherapy of Cancer and Autoimmunity."

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    Time
    13:00
    Location
    Wolfson Building for Biological Research
    Auditorium
    Lecturer
    Prof. Yoram Reiter
    Faculty of Biology and Technion Integrated Cancer Center Technion-Israel Institute of Technology
    Organizer
    Department of Immunology
    Contact
    Lecture
  • Date:21MondayJanuary 2019

    Foundations of Computer Science Seminar

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    Time
    14:30 - 16:00
    Title
    Reliable and Interpretable Deep Learning
    Location
    Jacob Ziskind Building
    Room 155
    Lecturer
    Dana Drachsler-Cohen
    ETH Zurich
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar, Department of Computer Science and Applied Mathematics
    Faculty of Mathematical Sciences Seminar, Department of Mathematics
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of In this talk, I will present two novel, complementary method...»
    In this talk, I will present two novel, complementary methods for making deep learning models more reliable and interpretable.
    First, I will present AI2, a technique for proving that a neural network satisfies a given property (e.g., robustness). The key idea is to leverage abstract interpretation to soundly over-approximate the network's behavior, enabling the analysis of large convolutional models, for the first time. Then, I will present DL2, a method which bridges logic and differentiable reasoning, allowing one to both pose interesting queries on deep models as well as train them to satisfy formal properties which capture domain knowledge.
    Finally, I will briefly discuss few promising research directions where applications of automated reasoning, both discrete and probabilistic, can be effective in solving key challenges in systems (e.g., programmable networks) and security (e.g., differential privacy).

    Bio: Dana Drachsler-Cohen is an ETH Postdoctoral Fellow at the department of Computer Science, ETH Zurich. Her research interests span automated reasoning, program synthesis and machine learning. She obtained her PhD from the Computer Science Department at the Technion in 2017.
    Lecture
  • Date:22TuesdayJanuary 2019

    Connecting the dots: functional and structural insights into the Legionella pneumophila Dot/Icm secretion system

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    Time
    10:00 - 11:00
    Location
    Nella and Leon Benoziyo Building for Biological Sciences
    Auditorium
    Lecturer
    Dr. David Chetrit
    Dept. of Microbial Pathogenesis, Yale Univ.School of Medicine
    Organizer
    Department of Biomolecular Sciences
    Contact
    AbstractShow full text abstract about Type IV secretion systems (T4SS) are widespread in bacteria ...»
    Type IV secretion systems (T4SS) are widespread in bacteria and despite their fundamental importance in processes such as DNA conjugation and pathogenesis of plants, animals and humans, they are among the most complex and yet arguably the least understood secretion systems in the prokaryotic kingdom. Using live fluorescence microscopy in conjunction with cryo-electron tomography, we determined the in-situ structure of the T4SS of the respiratory pathogen Legionella pneumophila, called Dot/Icm. Unexpectedly, we have discovered that the major ATPases energizing center in the cytosol of the bacterial cell creates a dynamic assembly and forms a unique central channel in that it is constructed by a hexameric array of dimeric proteins. We have showed that the ATPase DotB cycles between the cytosol and the Type IV machine, indicating that it is involved in energizing the Type IV apparatus once a signal is received to initiate protein translocation. Our data changed the existing paradigm for how T4SS function and provides new insights for future studies that are important for a complete understanding of host pathogen interaction processes.
    Lecture
  • Date:22TuesdayJanuary 2019

    Understanding properties of advanced low-dimensional materials by low-voltage atomic-scale TEM experiments

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    Time
    11:00 - 12:00
    Location
    Perlman Chemical Sciences Building
    Room 404
    Lecturer
    Prof. Ute Kaiser
    Central Facility Materials Science Electron Microscopy, Ulm University, Ulm
    Organizer
    Department of Materials and Interfaces
    Contact
    AbstractShow full text abstract about A new type of transmission electron microscopes operating at...»
    A new type of transmission electron microscopes operating at electron energies between 80keV and 20keV has been developed to obtain structural and electronic properties of advanced low-dimensional material at the atomic scale. It allows to undercut most of the materials knock-on damage thresholds and enables sub-Angstroem resolution in an 4000x4000 pixels, single-shoot image down to 40keV by correcting not only the geometrical aberrations of the objective lens but also its chromatic aberration. During the imaging process, the interaction of the beam electrons with the low-dimensional material can, nevertheless, results in changes of the atomic structure due to ionization and radiolysis, and sophisticated sample preparation methods are employed to reduce these effects. In this talk, we briefly outline key instrumental and methodological developments and report on structural properties of low-dimensional materials. We not only determine the structure of the pristine material but also use the electron beam to engineer defined properties. Thus, we show for instance the dynamics of extended defects in MoTe2 and WS2 and the creation of a commensurate charge density wave (CDW) in a monolayer 1T-TaSe2, as well as properties of MnPS3, and moreover the dynamics and bond order changing of dirhenium molecule in single-walled carbon nanotubes. Finally we intercalate bilayer graphene by lithium and study in-situ lithiation and delithiation between bilayer graphene, identify single Li atoms as well as the structure of the new high density crystalline Li- phase.
    Lecture
  • Date:22TuesdayJanuary 2019

    Algebraic Geometry and Representation Theory Seminar

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    Time
    11:15 - 12:30
    Title
    Structure of degenerate principal series of exceptional groups
    Location
    Jacob Ziskind Building
    Room 155
    Lecturer
    Avner Segal
    -
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar, Department of Computer Science and Applied Mathematics
    Faculty of Mathematical Sciences Seminar, Department of Mathematics
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of The reducibility and structure of parabolic inductions is a ...»
    The reducibility and structure of parabolic inductions is a basic problem in the representation theory of p-adic groups.
    Lecture
  • Date:22TuesdayJanuary 2019

    Synaptic tenacity: When everything changes, do things really stay the same?

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    Time
    12:30
    Location
    Nella and Leon Benoziyo Building for Brain Research
    Lecturer
    Prof. Noam Ziv
    Rappaport Faculty of Medicine, Technion, Haifa
    Organizer
    Department of Neurobiology
    Contact
    DetailsShow full text description of Benoziyo Brain Research Building Room 113 Host: Dr.Ivo Sp...»
    Benoziyo Brain Research Building Room 113

    Host: Dr.Ivo Spiegel ivo.spiegel@weizmann.ac.il tel: 4415
    For assistance with accessibility issues, please contact naomi.moses@weizmann.ac.il

    AbstractShow full text abstract about Activity-dependent modifications to synaptic connections – s...»
    Activity-dependent modifications to synaptic connections – synaptic plasticity – is widely believed to represent a fundamental mechanism for altering network function. This belief also implies, however, that synapses, when not driven to change their properties by physiologically relevant stimuli, should retain these properties over time. Otherwise, physiologically relevant modifications would be gradually lost amidst spurious changes and spontaneous drift. We refer to the capacity of synapses to maintain their properties over behaviorally relevant time scales as 'synaptic tenacity'.

    The seminar will examine the challenges to synaptic tenacity imposed by the short lifetimes of synaptic molecules, their inherent dynamics and the logistics of replenishing remote synapses with these molecules at appropriate amounts and stoichiometries. It will then examine the effects these processes have on the (in)stability of synaptic properties , on synaptic size configurations and distributions and on the scaling of these distributions. Finally, it will compare the magnitudes of synaptic changes driven by these processes to those of changes driven by deterministic, activity-dependent synaptic plasticity processes.

    Lecture
  • Date:22TuesdayJanuary 2019

    Special Guest Seminar with Prof. Meytal Landau

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    Time
    14:00
    Title
    Functional Protein Fibrils as Antibacterial Agents and Targets
    Location
    Arthur and Rochelle Belfer Building for Biomedical Research
    Botnar Auditorium
    Lecturer
    Prof. Meytal Landau
    Assistant Professor, Faculty of Biology, Technion, Israel Institute of Technology, Haifa, Israel
    Organizer
    Department of Molecular Genetics
    Guest Lecture
    Contact
    Lecture
  • Date:23WednesdayJanuary 2019

    Machine Learning and Statistics Seminar

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    Time
    11:15 - 12:15
    Title
    The Gaussian Maximum Likelihood Approach for Independent Component and Vector Analysis
    Location
    Jacob Ziskind Building
    Room 1
    Lecturer
    Amir Weiss
    Tel Aviv University
    Organizer
    Faculty of Mathematics and Computer Science
    Faculty of Mathematical Sciences Seminar, Department of Computer Science and Applied Mathematics
    Faculty of Mathematical Sciences Seminar, Department of Mathematics
    Faculty of Mathematical Sciences Seminar
    Contact
    DetailsShow full text description of The Blind Source Separation (BSS) problem consists of retrie...»
    The Blind Source Separation (BSS) problem consists of retrieving signals of interest, termed the sources, from a dataset consisting of their mixtures. One of the most popular and common paradigms for solving the BSS problem is Independent Component Analysis (ICA), where the sources are assumed to be (only) mutually statistically independent random processes, and the mixtures are assumed to be linear combinations thereof, where the linear mixing operator is unknown. In this talk, we shall start with the Gaussian Maximum Likelihood (GML) approach for the semi-blind problem, in which the sources are assumed to be temporally-diverse Gaussian processes. Based on the principles of this approach, we shall then discuss two extensions. First, the noisy Gaussian ICA problem, for which two asymptotically optimal solutions, w.r.t. two different optimality criteria, will be presented. We shall see (both analytically and empirically) that these solutions possess attractive properties even for non-Gaussian mixtures. Then, we shall consider the Independent Vector Analysis (IVA) framework, which has emerged in recent years as an extension of ICA into multiple datasets of mixtures. In IVA, the sources in each set are independent, but may depend on sources in the other sets. We will show that in IVA, the GML approach leads to consistent separation regardless of the sources' distributions.
    Lecture

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