Institution
Humboldt University of Berlin
Education•Berlin, Germany•
About: Humboldt University of Berlin is a education organization based out in Berlin, Germany. It is known for research contribution in the topics: Population & Transplantation. The organization has 33671 authors who have published 61781 publications receiving 1908102 citations. The organization is also known as: Humboldt-Universität zu Berlin & Universitas Humboldtiana Berolinensis.
Papers published on a yearly basis
Papers
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TL;DR: The physics of the SLAC and KEK B Factories are described in this paper, with a brief description of the detectors, BaBar and Belle, and data taking related issues.
Abstract: This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C.
413 citations
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TL;DR: This work extends the definition of a convex risk measure to a conditional framework where additional information is available and introduces a suitably defined dynamic version of the class of entropic risk measures.
Abstract: We extend the definition of a convex risk measure to a conditional framework where additional information is available. We characterize these risk measures through the associated acceptance sets and prove a representation result in terms of conditional expectations. A suitable regularity property of conditional risk measures is defined and discussed. Finally, we introduce the concept of a dynamic convex risk measure as a family of successive conditional convex risk measures and characterize those satisfying some natural time consistency properties. As a reference example, illustrating all the proposed developments, we introduce a suitably defined dynamic version of the class of entropic risk measures.
412 citations
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TL;DR: An integrative model of telomere shortening and signaling is developed and suggests that t-loop formation hinders access of repair proteins to telomeres, leading to accumulation of a basic sites and single-strand breaks.
Abstract: Replicative senescence is tied into organismal aging processes in more than one respect, and telomeres appear to be the major trigger of replicative senescence under many conditions in vitro and in vivo. However, the structure-function relationships in telomeres, the mechanisms of telomere shortening with advancing replicative age, and the regulation of senescence by telomeres are far from understood. Combining recent data on telomere structure, function of telomere-binding proteins, and sensitivity of telomeres to oxidative damage, an integrative model of telomere shortening and signaling is developed. The model suggests that t-loop formation hinders access of repair proteins to telomeres, leading to accumulation of a basic sites and single-strand breaks. These might contribute to accelerated telomere shortening by transient stalling of replication as well as, if present in high concentrations, to a relief of torsional tension which might destabilize the telomeric loop structure. As a result, the single-stranded G-rich overhang, which is present at the very ends of telomeres but is normally protected at the base of the telomeric loop, will be exposed to the nucleoplasm. Free G-rich telomeric single strands are a strong inductor of the p53 pathway, and exposure of the overhangs seems to be the first step in the signal transduction cascade to replicative senescence.
411 citations
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TL;DR: A short history of metabolic pathway analysis can be found in this paper, where computer-aided algorithms for the synthesis of metabolic pathways are discussed and important algebraic concepts used in pathway analysis, such as null space and convex cone, are explained.
Abstract: This article reviews the relatively short history of metabolic pathway analysis. Computer-aided algorithms for the synthesis of metabolic pathways are discussed. Important algebraic concepts used in pathway analysis, such as null space and convex cone, are explained. It is demonstrated how these concepts can be translated into meaningful metabolic concepts. For example, it is shown that the simplest vectors spanning the region of all admissible fluxes in stationary states, for which the term elementary flux modes was coined, correspond to fundamental pathways in the system. The concepts are illustrated with the help of a reaction scheme representing the glyoxylate cycle and adjacent reactions of aspartate and glutamate synthesis. The interrelations between pathway analysis and metabolic control theory are outlined. Promising applications for genome annotation and for biotechnological purposes are discussed. Armed with a better understanding of the architecture of cellular metabolism and the enormous amount of genomic data available today, biochemists and biotechnologists will be able to draw the entire metabolic map of a cell and redesign it by rational and directed metabolic engineering.
411 citations
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TL;DR: This work screened a large number of ChR2 point mutants and discovered a dramatic increase in photocurrent amplitude after threonine-to-cysteine substitution at position 159, which suggests it may become the standard for light-controlled activation of neurons.
Abstract: Channelrhodopsin-2 (ChR2) has become an indispensable tool in neuroscience, allowing precise induction of action potentials with short light pulses. A limiting factor for many optophysiological experiments is the relatively small photocurrent induced by ChR2. We screened a large number of ChR2 point mutants and discovered a dramatic increase in photocurrent amplitude after threonine-to-cysteine substitution at position 159. When we tested the T159C mutant in hippocampal pyramidal neurons, action potentials could be induced at very low light intensities, where currently available channelrhodopsins were unable to drive spiking. Biophysical characterization revealed that the kinetics of most ChR2 variants slows down considerably at depolarized membrane potentials. We show that the recently published E123T substitution abolishes this voltage sensitivity and speeds up channel kinetics. When we combined T159C with E123T, the resulting double mutant delivered fast photocurrents with large amplitudes and increased the precision of single action potential induction over a broad range of frequencies, suggesting it may become the standard for light-controlled activation of neurons.
410 citations
Authors
Showing all 34115 results
Name | H-index | Papers | Citations |
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Karl J. Friston | 217 | 1267 | 217169 |
Peer Bork | 206 | 697 | 245427 |
Raymond J. Dolan | 196 | 919 | 138540 |
Stefan Schreiber | 178 | 1233 | 138528 |
Andreas Pfeiffer | 149 | 1756 | 131080 |
Thomas Hebbeker | 148 | 1984 | 114004 |
Thomas Lohse | 148 | 1237 | 101631 |
Jean Bousquet | 145 | 1288 | 96769 |
Hermann Kolanoski | 145 | 1279 | 96152 |
Josh Moss | 139 | 1019 | 89255 |
R. D. Kass | 138 | 1920 | 107907 |
W. Kozanecki | 138 | 1498 | 99758 |
U. Mallik | 137 | 1625 | 97439 |
C. Haber | 135 | 1507 | 98014 |
Christophe Royon | 134 | 1453 | 90249 |