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פברואר 01, 2010
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Date:03שלישימאי 2011הרצאה
p53, a novel regulator of lipid metabolism pathways
More information שעה 12:15 - 12:15מיקום בניין וולפסון למחקר ביולוגימרצה Ido Goldstein מארגן המחלקה לביולוגיה מולקולרית של התאצרו קשר תקציר Show full text abstract about Maintaining normal lipid homeostasis is crucial for every bi...» Maintaining normal lipid homeostasis is crucial for every biological system. Although the transport of lipids in circulation in the form of lipoprotein complexes is an elaborate process orchestrated mainly by the liver, the molecular underpinnings of hepatic lipoprotein regulation are not entirely resolved. In this study, we identify a
novel role for the p53 protein in regulating lipid and lipoprotein metabolism, a process not conceptually conceived as related to p53, which is known mainly in its tumor suppressive functions. Gene expression microarray analysis revealed a group of 341 genes whose expression was induced by p53 in the liver-derived cell line HepG2.
Twenty of these genes encode proteins involved in many aspects of lipid homeostasis, especially lipoprotein metabolism. The mode of regulation of three representative genes (pltp, abca12 and cel) was further characterized. In addition to HepG2, the genes were induced in a p53-dependent manner in other cell types namely Hep3B cells, mouse hepatocytes, human liver cells and fibroblasts. Furthermore, p53 was found to bind to their promoter in designated p53 responsive elements (as measured by chromatin immunoprecipitation) and was able to increase the transcription of a reporter gene located downstream of the genes' promoters. Of note, p53 induced a significant elevation in the protein level of PLTP and CEL. Importantly, p53 augmented the activity of secreted PLTP, which plays a major role in lipoprotein biology and atherosclerosis pathology. These findings expose another layer of p53 functions unrelated to tumor suppression and render it a novel regulator of hepatic lipid metabolism and consequently of systemic lipid homeostasis and atherosclerosis development.
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Date:03שלישימאי 2011אירועי תרבות
"Aristrocrats" - Cameri Theater
More information שעה 20:30 - 20:30מיקום אודיטוריום מיכאל סלעצרו קשר -
Date:04רביעימאי 2011הרצאה
Forum on Mathematical Principles in Biology
More information שעה 10:00 - 11:00כותרת A design principle for protein promiscuityמיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Dima Lukatsky מארגן המחלקה לביולוגיה מולקולרית של התאצרו קשר -
Date:04רביעימאי 2011הרצאה
Fast Spectral Algorithms for Graph Partitioning and Graph Decomposition
More information שעה 11:00 - 11:00מיקום Ziskind Bldg.מרצה Nisheeth Vishnoi
Microsoft Research Indiaמארגן הפקולטה למתמטיקה ומדעי המחשב -
Date:04רביעימאי 2011הרצאה
Predictive Sparse Coding:A Dynamical Circuit Model of Early Sensory Processing
More information שעה 12:30 - 12:30מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Dmitri Chklovskii
Janelia Farm, HHMI, USAמארגן המחלקה למדעי המוחצרו קשר תקציר Show full text abstract about In early sensory systems, such as retina and olfactory bulb ...» In early sensory systems, such as retina and olfactory bulb in vertebrates or optic and antennal lobes in invertebrates, information about the world converges from a large number of receptors onto a much smaller number of projection neurons. Such bottleneck in the communication channel to the higher brain areas (Attneave, 1954, Barlow & Levick, 1976) can be overcome for sensory stimuli containing correlations by the predictive coding strategy (Srinivasan et al, 1982). In case of the retina, instantaneous subtraction of the least squares prediction compresses information and results in center-surround biphasic receptive fields. However, explaining variation of receptive fields with SNR (Srinivasan et al, 1982, Van Hateren, 1992, Atick & Redlich, 1990) would require circuit re-wiring which is unlikely on short time scales. Here we develop the predictive coding idea by proposing that a non-linear recurrent neuronal circuit can implement predictive coding adaptively: stimuli of different SNR result in different inhibitory surrounds. We solve the transient dynamics of this circuit in response to a step-like stimulus and demonstrate that it communicates a residual of the regularization path to higher brain areas. Thus, we are able to map a non-trivial computation on a concrete neuronal circuit and provide a theoretical framework to understand neural coding for many physiological experiments. -
Date:04רביעימאי 2011אירועי תרבות
"Aristrocrats" - Camari Theater
More information שעה 20:30 - 20:30מיקום אודיטוריום מיכאל סלעצרו קשר -
Date:05חמישימאי 2011הרצאה
Uniqueness and non-uniqueness for stochastic heat equations with H"older continuous coefficients
More information שעה 11:00 - 11:00מיקום Ziskind Bldg.מרצה Leonid Mytnik
Technionמארגן הפקולטה למתמטיקה ומדעי המחשב -
Date:05חמישימאי 2011הרצאה
TBA
More information שעה 11:15 - 12:30מיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Prof. Elad Schneidman
Department of Neurobiologyמארגן הפקולטה לפיזיקהצרו קשר -
Date:05חמישימאי 2011סימפוזיונים
Optimal population coding by noisy spiking neurons
More information שעה 11:15 - 12:30מיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Prof. Elad Schneidman
Weizmannמארגן הפקולטה לפיזיקהצרו קשר תקציר Show full text abstract about The In different neural systems, the collective activity of...» The In different neural systems, the collective activity of populations of neurons responding to natural-istic stimuli is well described by second order “maximum entropy” or Ising models. We asked, how should such interactions in the network be organized to maximize the amount of information represent-ed in population responses about the stimulus it was presented with? To this end, we extended the line-ar-nonlinear Poisson model of single neurons to include pairwise interactions, yielding a stimulus de-pendent, pairwise maximum entropy model. We found that as we varied the noise level in single neurons and the distribution of network inputs, the optimal pairwise interactions smoothly interpolated to achieve network functions that are usually regarded as discrete – stimulus decorrelation, error correc-tion, and independent encoding. These functions reflected a tradeoff between efficient consumption of finite neural bandwidth, and the use of redundancy to mitigate noise. Spontaneous activity in the optimal network reflected stimulus induced activity patterns, and single neuron response variability overes-timated network noise. Our analysis suggests that rather than having a single coding principle hardwired in their architecture, networks in the brain should adapt their function to changing noise and stimulus correlations. Initial results from the vertebrate retina indeed show how it relies on the network’s ‘ground states’ to encode information about the stimulus to the brain. -
Date:05חמישימאי 2011הרצאה
A Universal and Exact Linear Framework for Estimation Registration and Recognition of Deformable Objects
More information שעה 12:00 - 12:00מיקום Ziskind Bldg.מרצה Joseph M. Francos
Ben-Gurion Universityמארגן הפקולטה למתמטיקה ומדעי המחשב -
Date:05חמישימאי 2011הרצאה
Modeling the early steps of viral infection and analysis of cytoplasmic viral trajectories
More information שעה 14:15 - 14:15כותרת Astro Roomמיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה David Holcman
Ecole Normale Superieure, Franceמארגן המחלקה לפיזיקה של מערכות מורכבותצרו קשר תקציר Show full text abstract about Most viruses enter the cell through an endocytic pathway and...» Most viruses enter the cell through an endocytic pathway and subsequently travel through the cytoplasm inside an endosomal compartment before reaching the nucleus. To pursue their fate, viruses have to escape the endosome and deliver their genetic payload in the cytoplasm before being degraded. Although the escape process relies on the conformational changes of glycoproteins involved in membrane fusion, the details are still missing. To examine the escape dynamics, we first present a biophysical model and mathematical analysis to study cytoplasmic trafficking and the mean first passage time to reach any nuclear pores. Using Markov Jump processes, we then estimate the time for glycoproteins to change conformation and reach their fusogenic state, leading to fusion and viral escape from an endosome. We shall study separately the case of enveloped (influenza) and non-enveloped viruses (Adeno-Associated Virus). Finally, we will present a preliminary analysis to discriminate binding from crowding of recent acquired viral trajectories and we will finish by presenting some simulations of stochastic viral trajectories in a reconstituted EM picture of a cell. -
Date:08ראשוןמאי 2011הרצאה
"Biomineralization strategies in the acorn barnacle Balanus amphitrite"
More information שעה 10:00 - 12:00מיקום המשכן ללימודי מוסמכים על-שם דוד לופאטימרצה Gal Mor Khalifa
M.Sc. student of Prof. Lia Addadi & Prof. Stephen Weiner Department of Structural Bioloy, WISמארגן המחלקה לביולוגיה מבנית וכימיתצרו קשר -
Date:08ראשוןמאי 2011הרצאה
Property Testing Lower Bounds via Communication Complexity
More information שעה 11:00 - 11:00מיקום Ziskind Bldg.מרצה Kevin Matulef
IIIS, Tsinghua Universityמארגן הפקולטה למתמטיקה ומדעי המחשב -
Date:08ראשוןמאי 2011הרצאה
The geological input of the Japan happenings and a look at our region
More information שעה 11:00 - 11:00מיקום בניין משפחת זוסמןמרצה Prof. Emanuel Mazor
Weizmann Institute of Science Environmental Sciences Dept.מארגן המחלקה למדעי כדור הארץ וכוכבי הלכתצרו קשר -
Date:08ראשוןמאי 2011הרצאה
Journal club - A discussion on selected articles
More information שעה 12:30 - 14:00מיקום מעבדה על-שם דני נ. היינמןמרצה Dr. Nir Sapir מארגן מרכז לאסטרופיסיקה עש נלה וליאון בנוזיוצרו קשר -
Date:08ראשוןמאי 2011הרצאה
To be announced
More information שעה 13:00 - 13:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Efrat Dvash
Menachem Rubinstein's group Dept. of Molecular Genetics, WISמארגן המחלקה לגנטיקה מולקולריתצרו קשר -
Date:08ראשוןמאי 2011הרצאה
Sphingosine-1-phosphate: frpom insipid lipid to a regulator of cancer and inflammation
More information שעה 14:00 - 14:00מיקום בניין ע"ש מקס ולילאן קנדיוטימרצה Prof. Sarah Spiegel
Dept. Biochemistry and Molecular Biology Virginia Commonwealth University School of Medicine Richmond, VA. USAמארגן המחלקה לאימונולוגיה ורגנרציה ביולוגיתצרו קשר -
Date:09שנימאי 2011אירועי תרבות
טקס יום הזיכרון לחללי מערכות ישראל ולנפגעי פעולות האיבה
More information שעה 11:00 - 12:45מיקום בניין הלן ומילטון קימלמןצרו קשר -
Date:11רביעימאי 2011הרצאה
Lumen formation in the Drosophila heart
More information שעה 10:00 - 10:00מיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Prof. Talila Volk
Dept. of Molecular Genetics, WISצרו קשר -
Date:11רביעימאי 2011סימפוזיונים
Faculty of Chemistry Colloquium- Prof. Harold Kroto
More information שעה 11:00 - 12:30כותרת CARBON IN NANO AND OUTER SPACEמיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Harold Kroto
Nobel Laureate for the discovery of the C60 Dept. of Chemistry & Biochemistry The Florida State Universityמארגן הפקולטה לכימיהצרו קשר תקציר Show full text abstract about The age-old awe that man has had for the heavens has driven ...» The age-old awe that man has had for the heavens has driven almost all aspects of human culture and knowledge and resulted in technologies with generally positive, though occasionally negative effect. Arguably the most positive have taken place since Galileo recognized that the phases of Venus provided the evidence that confirmed the Copernican heliocentric system and cemented his position firmly as the “Father of Science”. From this moment on we had, at long last, a straightforward philosophical construct and language which enabled mankind to determine what is and is not “True”. Particularly important truths have resulted from the curiosity that humans have had for a detailed understanding of the way Universe works. This led to the development of astrophysics and the associated technologies that have been spun-off. Not least of these has been the telescope – from Galileo’s beautiful original design to the fantastic satellite-born devices put up by NASA. These have not only enabled us to observe the planets and stars more clearly but we have been able to see to the very edge of the Universe and make a plethora of discoveries about all aspects of the Universe from the occupants of the space between stars to the processes occurring deep inside stars. Perhaps the most fundamental advance based on space observations led to the development of Classical Mechanics in order to understand the motions of the planets and comets and concommitantly the development Calculus, one of the greatest of Mathematical achievements. As Quantum Mechanics developed along with Spectroscopy it was inevitable that we should start to study the atomic and molecular composition of heavenly bodies - first hot stars as well as cool comets. With the development of radiotelescopes, the very cold interstellar medium was found to be a veritable Pandora's Box, full to the brim with fascinating and exotic molecules, dust particles and also some highly puzzling material responsible for some as yet unidentified spectroscopic features. These latter are known as the Diffuse Interstellar Bands (DIBs) first observed in the 1920s.
Particularly fascinating, curious and crucial has been the role that the element carbon has played in almost every aspect of the development of our understanding of both the physical and natural sciences. The fact that the element is at all abundant is due to a curious set of coincidences involving its nucleosynthesis from helium in stars. If one furthermore adds into the overall carbon equation its uniquely profuse chemistry, ie Organic Chemistry, it is hard to conceive that life could be based on any other element. The most recent big surprise that the element had up its sleeve was the existence of C60, Buckminsterfullerene, the third well-defined form of carbon. The discovery was made serendipitously in 1985 during laboratory experiments which attempted to explain the chemical synthesis of some unusually long linear carbon chain molecules detected in the interstellar medium in the 1970’s. A second aim of these experiments involved curiosity as to whether the carriers of the DIBs might be long linear carbon chains. Interestingly the extraction of C60 in 1990 by Kraetschmer and Huffman resulted from experiments aimed at understanding another mysterious feature known as the 217nm hump and conjectured to also involve carbon – perhaps carbonaceous dust particles. The fact that this third, well-defined, form of carbon had been hiding in the shadows since time immemorial brings to mind the mysterious character lurking in the dark streets of Vienna, made famous by Orson Welles in the classic movie “The Third Man”. In fact we now know that the molecule forms fleetingly within sooting flames but is immediately destroyed as it passes through the flame barrier into an oxygen atmosphere. On the basis of such revelations the suggestion that C60 might exist in space and be responsible for the DIBs (Kroto & Jura) seemed an as good, if not a better, possibility than most other ideas that had heretofore been proposed. Especially compelling support for the idea that C60 existed in space lay in the fact that the original discovery was made serendipitously during laboratory experiments designed to simulate the atmospheric conditions in cool red giant carbon stars. This conjecture has just been confirmed by Cami et al who have found infra red bands in the spectra obtained by NASA’s Spitzer satellite telescope. The discovery also makes some recent work here at FSU on endohedral fullerenes, in which atoms are trapped inside the carbon cage, extremely relevant to certain anomalous isotope ratios observed in meteorites, in particular carbonaceous chondrites. This is yet another example of the remarkably synergistic relationship between terrestrial and space science. In these difficult times it lends useful support for the fundamental value of "Blue Skies" or perhaps more accurately “Black Skies” cross-disciplinary research. All these results taken together suggest that the 90 year-old mystery of the carrier of the DIBs might be close to being resolved at long last.
