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
Papers
More filters
••
Paul Scherrer Institute1, University of Helsinki2, University of Leeds3, Goethe University Frankfurt4, University of Beira Interior5, University of Innsbruck6, CERN7, California Institute of Technology8, Helsinki Institute of Physics9, University of Eastern Finland10, University of Vienna11, Lebedev Physical Institute12, Leibniz Association13, Finnish Meteorological Institute14, Carnegie Mellon University15
TL;DR: It is shown, in experiments performed with the CLOUD (Cosmics Leaving Outdoor Droplets) chamber at CERN, that sulfuric acid and oxidized organic vapors at atmospheric concentrations reproduce particle nucleation rates observed in the lower atmosphere.
Abstract: Atmospheric new-particle formation affects climate and is one of the least understood atmospheric aerosol processes. The complexity and variability of the atmosphere has hindered elucidation of the fundamental mechanism of new-particle formation from gaseous precursors. We show, in experiments performed with the CLOUD (Cosmics Leaving Outdoor Droplets) chamber at CERN, that sulfuric acid and oxidized organic vapors at atmospheric concentrations reproduce particle nucleation rates observed in the lower atmosphere. The experiments reveal a nucleation mechanism involving the formation of clusters containing sulfuric acid and oxidized organic molecules from the very first step. Inclusion of this mechanism in a global aerosol model yields a photochemically and biologically driven seasonal cycle of particle concentrations in the continental boundary layer, in good agreement with observations.
446 citations
••
TL;DR: Development of techniques for extraction, cleanup, separation, and sample storage that introduce minimal artifacts to increase the speed, sensitivity, and specificity of analytical techniques, as well as the development of techniques that can differentiate between abundant, naturally occurring particles, and manufactured nanoparticles are needed.
Abstract: Advances in the study of the environmental fate, transport, and ecotoxicological effects of engineered nanomaterials (ENMs) have been hampered by a lack of adequate techniques for the detection and quantification of ENMs at environmentally relevant concentrations in complex media. Analysis of ENMs differs from traditional chemical analysis because both chemical and physical forms must be considered. Because ENMs are present as colloidal systems, their physicochemical properties are dependent on their surroundings. Therefore, the simple act of trying to isolate, observe, and quantify ENMs may change their physicochemical properties, making analysis extremely susceptible to artifacts. Many analytical techniques applied in materials science and other chemical/biological/physical disciplines may be applied to ENM analysis as well; however, environmental and biological studies may require that methods be adapted to work at low concentrations in complex matrices. The most pressing research needs are the development of techniques for extraction, cleanup, separation, and sample storage that introduce minimal artifacts to increase the speed, sensitivity, and specificity of analytical techniques, as well as the development of techniques that can differentiate between abundant, naturally occurring particles, and manufactured nanoparticles.
446 citations
••
TL;DR: This paper surveys the theoretical and computational development of the restricted maximum likelihood approach for the estimation of covariance matrices in linear stochastic models, and gives a new derivation of this approach, valid under very weak conditions on the noise.
Abstract: This paper surveys the theoretical and computational development of the restricted maximum likelihood (REML) approach for the estimation of covariance matrices in linear stochastic models. A new derivation of this approach is given, valid under very weak conditions on the noise. Then the calculation of the gradient of restricted loglikelihood functions is dis- cussed, with special emphasis on the case of large and sparse model equations with a large number of unknown covariance components and possibly incomplete data. It turns out that the gradient calculations require hardly any extra storage, and only a small multiple of the number of operations needed to calculate the function values alone. The analytic gradient procedure was integrated into the VCE package for co- variance component estimation in large animal breeding models. It resulted in dramatic improvements of performance over the previous implementation with finite difference gradients. An example with more than 250 000 normal equations and 55 covariance components took hours instead of days of CPU time, and this was not an untypical case.
446 citations
••
TL;DR: A protein is described, cytohesin-1, which specifically interacts with the intracellular portion of the integrin beta 2 chain (CD18), which shows homology to the yeast SEC7 gene product and bears a pleckstrin homology (PH) domain.
445 citations
••
Centre national de la recherche scientifique1, Roma Tre University2, University of Vienna3, Indiana Statewide Testing for Educational Progress-Plus4, University of Rennes5, Kandilli Observatory and Earthquake Research Institute6, National Institute of Geophysics and Volcanology7, Istanbul Technical University8, University of Potsdam9, University of Orléans10
TL;DR: In this paper, the authors review the geodynamic evolution of the Aegean-Anatolia region and discuss strain localisation there over geological times, and they favour a model where slab retreat is the main driving engine, and successive slab tearing episodes are the main causes of this stepwise strain localization and the inherited heterogeneity of the crust is a major factor for localising detachments.
444 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 |