Institution
University of Vienna
Education•Vienna, Austria•
About: University of Vienna is a education organization based out in Vienna, Austria. It is known for research contribution in the topics: Population & Context (language use). The organization has 44686 authors who have published 95840 publications receiving 2907492 citations.
Topics: Population, Context (language use), Stars, Computer science, Galaxy
Papers published on a yearly basis
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TL;DR: This work considers three different geometric centrality measures, excentricity, status, and centroid value, that were originally used in the context of resource placement problems and shows that these quantities lead to useful descriptions of the centers of biological networks.
350 citations
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TL;DR: In this paper it is shown how a scenario tree may be constructed in an optimal manner on the basis of a simulation model of the underlying financial process by using a stochastic approximation technique.
Abstract: Multiperiod financial optimization is usually based on a stochastic model for the possible market situations. There is a rich literature about modeling and estimation of continuous-state financial processes, but little attention has been paid how to approximate such a process by a discrete-state scenario process and how to measure the pertaining approximation error.¶In this paper we show how a scenario tree may be constructed in an optimal manner on the basis of a simulation model of the underlying financial process by using a stochastic approximation technique. Consistency relations for the tree may also be taken into account.
350 citations
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TL;DR: In this article, a comparative analysis of the vibrational and structural properties of carbon nanotubes is presented, where the first-order Raman spectrum exhibits two lines at 1582 cm −1 and at 1350 cm−1.
350 citations
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TL;DR: In vivo footprinting experiments indicated that both the sp1 and E2F binding sites are occupied throughout the cell cycle, in line with the hypothesis that E 2F functions as a growth- and cell cycle regulated tethering factor between Sp1 and the basic transcription machinery.
Abstract: Within the region around 150 bp upstream of the initiation codon, which was previously shown to suffice for growth-regulated expression, the murine thymidine kinase gene carries a single binding site for transcription factor Sp1; about 10 bp downstream of this site, there is a binding motif for transcription factor E2F. The latter protein appears to be responsible for growth regulation of the promoter. Mutational inactivation of either the Sp1 or the E2F site almost completely abolishes promoter activity, suggesting that the two transcription factors interact directly in delivering an activation signal to the basic transcription machinery. This was verified by demonstrating with the use of glutathione S-transferase fusion proteins that E2F and Sp1 bind to each other in vitro. For this interaction, the C-terminal part of Sp1 and the N terminus of E2F1, a domain also present in E2F2 and E2F3 but absent in E2F4 and E2F5, were essential. Accordingly, E2F1 to E2F3 but not E2F4 and E2F5 were found to bind sp1 in vitro. Coimmunoprecipitation experiments showed that complexes exist in vivo, and it was estabilished that the distance between the binding sites for the two transcription factors was critical for optimal promoter activity. Finally, in vivo footprinting experiments indicated that both the sp1 and E2F binding sites are occupied throughout the cell cycle. Mutation of either binding motif abolished binding of both transcription factors in vivo, which may indicate cooperative binding of the two proteins to chromatin-organized DNA. Our data are in line with the hypothesis that E2F functions as a growth- and cell cycle regulated tethering factor between Sp1 and the basic transcription machinery.
350 citations
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University of Bern1, Centre national de la recherche scientifique2, Paul Scherrer Institute3, University of Mainz4, Natural Environment Research Council5, Swiss Federal Institute for Forest, Snow and Landscape Research6, Forschungszentrum Jülich7, Stanford University8, National Center for Atmospheric Research9, University of Exeter10, Columbia University11, University of Basilicata12, University of Vienna13, University of Barcelona14, Finnish Environment Institute15, American Museum of Natural History16, AGH University of Science and Technology17, Swansea University18, Silesian University of Technology19, Vytautas Magnus University20, University of Naples Federico II21, Anglia Ruskin University22
TL;DR: In this article, the authors used long-term δ13C tree-ring measurements across a European forest network to reconstruct the physiologically driven response of intercellular CO2 caused by atmospheric CO2 (Ca) trends.
Abstract: Considering the combined effects of CO2 fertilization and climate change drivers on plant physiology leads to a modest increase in simulated European forest transpiration in spite of the effects of CO2-induced stomatal closure. The Earth’s carbon and hydrologic cycles are intimately coupled by gas exchange through plant stomata1,2,3. However, uncertainties in the magnitude4,5,6 and consequences7,8 of the physiological responses9,10 of plants to elevated CO2 in natural environments hinders modelling of terrestrial water cycling and carbon storage11. Here we use annually resolved long-term δ13C tree-ring measurements across a European forest network to reconstruct the physiologically driven response of intercellular CO2 (Ci) caused by atmospheric CO2 (Ca) trends. When removing meteorological signals from the δ13C measurements, we find that trees across Europe regulated gas exchange so that for one ppmv atmospheric CO2 increase, Ci increased by ∼0.76 ppmv, most consistent with moderate control towards a constant Ci/Ca ratio. This response corresponds to twentieth-century intrinsic water-use efficiency (iWUE) increases of 14 ± 10 and 22 ± 6% at broadleaf and coniferous sites, respectively. An ensemble of process-based global vegetation models shows similar CO2 effects on iWUE trends. Yet, when operating these models with climate drivers reintroduced, despite decreased stomatal opening, 5% increases in European forest transpiration are calculated over the twentieth century. This counterintuitive result arises from lengthened growing seasons, enhanced evaporative demand in a warming climate, and increased leaf area, which together oppose effects of CO2-induced stomatal closure. Our study questions changes to the hydrological cycle, such as reductions in transpiration and air humidity, hypothesized to result from plant responses to anthropogenic emissions.
349 citations
Authors
Showing all 45262 results
Name | H-index | Papers | Citations |
---|---|---|---|
Tomas Hökfelt | 158 | 1033 | 95979 |
Wolfgang Wagner | 156 | 2342 | 123391 |
Hans Lassmann | 155 | 724 | 79933 |
Stanley J. Korsmeyer | 151 | 316 | 113691 |
Charles B. Nemeroff | 149 | 979 | 90426 |
Martin A. Nowak | 148 | 591 | 94394 |
Barton F. Haynes | 144 | 911 | 79014 |
Yi Yang | 143 | 2456 | 92268 |
Peter Palese | 132 | 526 | 57882 |
Gérald Simonneau | 130 | 587 | 90006 |
Peter M. Elias | 127 | 581 | 49825 |
Erwin F. Wagner | 125 | 375 | 59688 |
Anton Zeilinger | 125 | 631 | 71013 |
Wolfgang Waltenberger | 125 | 854 | 75841 |
Michael Wagner | 124 | 351 | 54251 |