scispace - formally typeset
Search or ask a question
Institution

University of Geneva

EducationGeneva, Switzerland
About: University of Geneva is a education organization based out in Geneva, Switzerland. It is known for research contribution in the topics: Population & Planet. The organization has 26887 authors who have published 65265 publications receiving 2931373 citations. The organization is also known as: Geneva University & Universite de Geneve.
Topics: Population, Planet, Galaxy, Exoplanet, Stars


Papers
More filters
Journal ArticleDOI
TL;DR: Plants utilize several families of photoreceptors to fine-tune growth and development over a large range of environmental conditions, and the molecular mechanisms involved include light-regulated subcellular localization of the photoreception, a large reorganization of the transcriptional program, and light- regulated proteolytic degradation of several photoreceptor and signaling components.
Abstract: Plants utilize several families of photoreceptors to fine-tune growth and development over a large range of environmental conditions. The UV-A/blue light sensing phototropins mediate several light responses enabling optimization of photosynthetic yields. The initial event occurring upon photon capture is a conformational change of the photoreceptor that activates its protein kinase activity. The UV-A/blue light sensing cryptochromes and the red/far-red sensing phytochromes coordinately control seedling establishment, entrainment of the circadian clock, and the transition from vegetative to reproductive growth. In addition, the phytochromes control seed germination and shade-avoidance responses. The molecular mechanisms involved include light-regulated subcellular localization of the photoreceptors, a large reorganization of the transcriptional program, and light-regulated proteolytic degradation of several photoreceptors and signaling components.

885 citations

Journal ArticleDOI
TL;DR: In this paper, the standard q-deformation of the Cartan-Weyl basis for o(3,2) ⋍ sp (4| R ) (real form of C2) is calculated.

882 citations

Journal ArticleDOI
A. A. Abdo1, A. A. Abdo2, Markus Ackermann3, Ivan Agudo4  +270 moreInstitutions (51)
Abstract: We have conducted a detailed investigation of the broadband spectral properties of the gamma-ray selected blazars of the Fermi LAT Bright AGN Sample (LBAS). By combining our accurately estimated Fermi gamma-ray spectra with Swift, radio, infra-red, optical, and other hard X-ray/gamma-ray data, collected within 3 months of the LBAS data taking period, we were able to assemble high-quality and quasi-simultaneous spectral energy distributions (SED) for 48 LBAS blazars. The SED of these gamma-ray sources is similar to that of blazars discovered at other wavelengths, clearly showing, in the usual log nu-log nu F-nu representation, the typical broadband spectral signatures normally attributed to a combination of low-energy synchrotron radiation followed by inverse Compton emission of one or more components. We have used these SED to characterize the peak intensity of both the low-and the high-energy components. The results have been used to derive empirical relationships that estimate the position of the two peaks from the broadband colors (i.e., the radio to optical, alpha(ro), and optical to X-ray, alpha(ox), spectral slopes) and from the gamma-ray spectral index. Our data show that the synchrotron peak frequency (nu(S)(peak)) is positioned between 10(12.5) and 10(14.5) Hz in broad-lined flat spectrum radio quasars (FSRQs) and between 10(13) and 10(17) Hz in featureless BL Lacertae objects. We find that the gamma-ray spectral slope is strongly correlated with the synchrotron peak energy and with the X-ray spectral index, as expected at first order in synchrotron-inverse Compton scenarios. However, simple homogeneous, one-zone, synchrotron self-Compton (SSC) models cannot explain most of our SED, especially in the case of FSRQs and low energy peaked (LBL) BL Lacs. More complex models involving external Compton radiation or multiple SSC components are required to reproduce the overall SED and the observed spectral variability. While more than 50% of known radio bright high energy peaked (HBL) BL Lacs are detected in the LBAS sample, only less than 13% of known bright FSRQs and LBL BL Lacs are included. This suggests that the latter sources, as a class, may be much fainter gamma-ray emitters than LBAS blazars, and could in fact radiate close to the expectations of simple SSC models. We categorized all our sources according to a new physical classification scheme based on the generally accepted paradigm for Active Galactic Nuclei and on the results of this SED study. Since the LAT detector is more sensitive to flat spectrum gamma-ray sources, the correlation between nu(S)(peak) and gamma-ray spectral index strongly favors the detection of high energy peaked blazars, thus explaining the Fermi overabundance of this type of sources compared to radio and EGRET samples. This selection effect is similar to that experienced in the soft X-ray band where HBL BL Lacs are the dominant type of blazars.

882 citations

Journal ArticleDOI
TL;DR: It is argued that the fundamental criteria for the amygdala to be a modular system are not met and the notion of a specific involvement of the human amygdala in the appraisal of relevant events that include, but are not restricted to, fear-related stimuli is suggested.
Abstract: Evidence from pioneering animal research has suggested that the amygdala is involved in the processing of aversive stimuli, particularly fear-related information. Fear is central in the evolution of the mammalian brain: it is automatically and rapidly elicited by potentially dangerous and deadly events. The view that the amygdala shares the main characteristics of modular systems, e.g. domain specificity, automaticity, and cognitive impenetrability, has become popular in neuroscience. Because of its computational properties, it has been proposed to implement a rapid-response 'fear module'. In this article, we review recent patient and neuroimaging data of the human brain and argue that the fundamental criteria for the amygdala to be a modular system are not met. We propose a different computational view and suggest the notion of a specific involvement of the human amygdala in the appraisal of relevant events that include, but are not restricted to, fear-related stimuli. Considering the amygdala as a 'relevance detector' would integrate the 'fear module' hypothesis with the concept of an evolved neural system devoted to the processing of a broader category of biologically relevant stimuli. In primates, socially relevant events appear to have become, through evolution, the dominant elements of the amygdala's domain of specificity.

881 citations


Authors

Showing all 27203 results

NameH-indexPapersCitations
JoAnn E. Manson2701819258509
Joseph L. Goldstein207556149527
Kari Stefansson206794174819
David Baltimore203876162955
Mark I. McCarthy2001028187898
Michael S. Brown185422123723
Yang Gao1682047146301
Napoleone Ferrara167494140647
Marc Weber1672716153502
Alessandro Melchiorri151674116384
Andrew D. Hamilton1511334105439
David P. Strachan143472105256
Andrew Beretvas1411985110059
Rainer Wallny1411661105387
Josh Moss139101989255
Network Information
Related Institutions (5)
Max Planck Society
406.2K papers, 19.5M citations

93% related

University of Oxford
258.1K papers, 12.9M citations

93% related

University College London
210.6K papers, 9.8M citations

93% related

Centre national de la recherche scientifique
382.4K papers, 13.6M citations

93% related

Yale University
220.6K papers, 12.8M citations

93% related

Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
2023171
2022520
20214,280
20204,142
20193,580
20183,395