The Weizmann Institute of Science is a public research university in Rehovot, Israel. It differs from other Israeli universities in that it offers only graduate and postgraduate tutelage in the science.It is a multidisciplinary research center, with around 2,500 scientists, postdoctoral fellows, Ph.D. and M.Sc. students, and scientific, technical, and administrative staff working at the Institute.Three Nobel laureates and three Turing Award laureates have been associated with the Weizmann Institute of Science. Wikipedia.
Weizmann Institute of Science | Date: 2016-08-22
A system and methods for controlling pulse parameters during transcranial magnetic stimulation are provided. Multiple coils are placed on external body parts, and are controlled using an external control unit coupled to a stimulator having fast switches. The timing of the switches, as well as other parameters within the stimulator, determine the pulse parameters, such as pulse shape. The variety of pulse shapes obtainable using such a system and methods provides controlled physiologic effects within an internal body organ.
Schwarz U.S.,University of Heidelberg |
Safran S.A.,Weizmann Institute of Science
Reviews of Modern Physics | Year: 2013
One of the most unique physical features of cell adhesion to external surfaces is the active generation of mechanical force at the cell-material interface. This includes pulling forces generated by contractile polymer bundles and networks, and pushing forces generated by the polymerization of polymer networks. These forces are transmitted to the substrate mainly by focal adhesions, which are large, yet highly dynamic adhesion clusters. Tissue cells use these forces to sense the physical properties of their environment and to communicate with each other. The effect of forces is intricately linked to the material properties of cells and their physical environment. Here a review is given of recent progress in our understanding of the role of forces in cell adhesion from the viewpoint of theoretical soft matter physics and in close relation to the relevant experiments. © 2013 American Physical Society.
Gunanathan C.,National Institute of Science Education and Research NISER |
Milstein D.,Weizmann Institute of Science
Chemical Reviews | Year: 2014
Activation of inert chemical bonds by transition metal complexes is an area of utmost importance. Efficient bond activation can provide a leading entry to successful catalytic design with the potential of providing greener synthetic methods for useful products. These coordinatively saturated and unsaturated ruthenium pincer complexes with heteroaromatic and aliphatic backbones developed in recent years exhibit new reactivities, activate strong chemical bonds, and act as efficient catalysts for several synthetic methods including unprecedented green transformations, the pivotal interest of this Review. One of the characteristic properties of pincer complexes is the ability to stabilize low valent metal complexes with uncommon geometries.
Klajn R.,Weizmann Institute of Science
Chemical Society Reviews | Year: 2014
In the past few years, spiropyran has emerged as the molecule-of-choice for the construction of novel dynamic materials. This unique molecular switch undergoes structural isomerisation in response to a variety of orthogonal stimuli, e.g. light, temperature, metal ions, redox potential, and mechanical stress. Incorporation of this switch onto macromolecular supports or inorganic scaffolds allows for the creation of robust dynamic materials. This review discusses the synthesis, switching conditions, and use of dynamic materials in which spiropyran has been attached to the surfaces of polymers, biomacromolecules, inorganic nanoparticles, as well as solid surfaces. The resulting materials show fascinating properties whereby the state of the switch intimately affects a multitude of useful properties of the support. The utility of the spiropyran switch will undoubtedly endow these materials with far-reaching applications in the near future. © 2014 The Royal Society of Chemistry.
Rybtchinski B.,Weizmann Institute of Science
ACS Nano | Year: 2011
Noncovalent systems are adaptive and allow facile processing and recycling. Can they be at the same time robust? How can one rationally design such systems? Can they compete with high-performance covalent materials? The recent literature reveals that noncovalent systems can be robust yet adaptive, self-healing, and recyclable, featuring complex nanoscale structures and unique functions. We review such systems, focusing on the rational design of strong noncovalent interactions, kinetically controlled pathway-dependent processes, complexity, and function. The overview of the recent examples points at the emergent field of noncovalent nanomaterials that can represent a versatile, multifunctional, and environmentally friendly alternative to conventional covalent systems. © 2011 American Chemical Society.
Lev S.,Weizmann Institute of Science
Nature Reviews Molecular Cell Biology | Year: 2010
The movement of lipids within and between intracellular membranes is mediated by different lipid transport mechanisms and is crucial for maintaining the identities of different cellular organelles. Non-vesicular lipid transport has a crucial role in intracellular lipid trafficking and distribution, but its underlying mechanisms remain unclear. Lipid-transfer proteins (LTPs), which regulate diverse lipid-mediated cellular processes and accelerate vectorial transport of lipid monomers between membranes in vitro, could potentially mediate non-vesicular intracellular lipid trafficking. Understanding the mechanisms by which lipids are transported and distributed between cellular membranes, and elucidating the role of LTPs in intracellular lipid transport and homeostasis, are currently subjects of intensive study. © 2010 Macmillan Publishers Limited. All rights reserved.
Haran G.,Weizmann Institute of Science
Current Opinion in Structural Biology | Year: 2012
Unfolded proteins under strongly denaturing conditions are highly expanded. However, when the conditions are more close to native, an unfolded protein may collapse to a compact globular structure distinct from the folded state. This transition is akin to the coil-globule transition of homopolymers. Single-molecule FRET experiments have been particularly conducive in revealing the collapsed state under conditions of coexistence with the folded state. The collapse can be even more readily observed in natively unfolded proteins. Time-resolved studies, using FRET and small-angle scattering, have shown that the collapse transition is a very fast event, probably occurring on the submicrosecond time scale. The forces driving collapse are likely to involve both hydrophobic and backbone interactions. The loss of configurational entropy during collapse makes the unfolded state less stable compared to the folded state, thus facilitating folding. © 2011 Elsevier Ltd.
Hausser J.,Weizmann Institute of Science |
Zavolan M.,Swiss Institute of Bioinformatics
Nature Reviews Genetics | Year: 2014
Comparative genomics analyses and high-throughput experimental studies indicate that a microRNA (miRNA) binds to hundreds of sites across the transcriptome. Although the knockout of components of the miRNA biogenesis pathway has profound phenotypic consequences, most predicted miRNA targets undergo small changes at the mRNA and protein levels when the expression of the miRNA is perturbed. Alternatively, miRNAs can establish thresholds in and increase the coherence of the expression of their target genes, as well as reduce the cell-to-cell variability in target gene expression. Here, we review the recent progress in identifying miRNA targets and the emerging paradigms of how miRNAs shape the dynamics of target gene expression. © 2014 Macmillan Publishers Limited. All rights reserved.
Fass D.,Weizmann Institute of Science
Annual Review of Biophysics | Year: 2012
It has been known for many decades that cell surface, soluble-secreted, and extracellular matrix proteins are generally rich in disulfide bonds, but only more recently has the functional diversity of disulfide bonding in extracellular proteins been appreciated. In addition to the classic mechanisms by which disulfide bonds enhance protein thermodynamic stability, disulfides in certain configurations contribute particular mechanical properties to proteins that sense and respond to tensile forces. Disulfides may help warp protein folds for the evolution of new functions, or they may fasten aggregation-prone flaps of polypeptide to protein surfaces to prevent fibrilization or oligomerization. Disulfides can also be used to package and secure macromolecular cargo for intercellular transport. A series of case studies illustrating diverse biophysical roles of disulfide bonding are reviewed, with a focus on proteins functioning in the extracellular environment. © 2012 by Annual Reviews. All rights reserved.
Geiger B.,Weizmann Institute of Science
Cold Spring Harbor perspectives in biology | Year: 2011
Cell adhesions mediate important bidirectional interactions between cells and the extracellular matrix. They provide an interactive interface between the extracellular chemical and physical environment and the cellular scaffolding and signaling machinery. This dynamic, reciprocal regulation of intracellular processes and the matrix is mediated by membrane receptors such as the integrins, as well as many other components that comprise the adhesome. Adhesome constituents assemble themselves into different types of cell adhesion structures that vary in molecular complexity and change over time. These cell adhesions play crucial roles in cell migration, proliferation, and determination of cell fate.