Institution
University of Geneva
Education•Geneva, Switzerland•
About: University of Geneva is a education organization based out in Geneva, Switzerland. It is known for research contribution in the topics: Population & Galaxy. 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, Galaxy, Planet, Stars, Context (language use)
Papers published on a yearly basis
Papers
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TL;DR: In the absolute rigidity range ∼60 to ∼500 GV, the antiproton p[over ¯], proton p, and positron e^{+} fluxes are found to have nearly identical rigidity dependence and the electron e^{-} flux exhibits a different rigidity dependent.
Abstract: A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in
primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49 × 105
antiproton events and 2.42 × 109 proton events. The fluxes and flux ratios of charged elementary particles
in cosmic rays are also presented. In the absolute rigidity range ∼60 to ∼500 GV, the antiproton ¯p, proton
p, and positron eþ fluxes are found to have nearly identical rigidity dependence and the electron e− flux
exhibits a different rigidity dependence. Below 60 GV, the ( ¯ p=p), ( ¯ p=eþ), and (p=eþ) flux ratios each
reaches a maximum. From ∼60 to ∼500 GV, the ( ¯ p=p), ( ¯ p=eþ), and (p=eþ) flux ratios show no rigidity
dependence. These are new observations of the properties of elementary particles in the cosmos.
464 citations
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TL;DR: In the ultraviolet the Neptune-mass exoplanet GJ 436b (also known as Gliese 436b) has transit depths of 56.3 ± 3.5% (1σ), far beyond the 0.69% optical transit depth, and it is inferred that the planet is surrounded and trailed by a large exospheric cloud composed mainly of hydrogen atoms.
Abstract: In the ultraviolet spectrum, the Neptune-mass exoplanet GJ 436b is shown to have transit depths far greater than those seen in the optical spectrum, indicating that it is surrounded and trailed by a large cloud composed mainly of hydrogen atoms. Observations of the Neptune-mass exoplanet GJ 436b in the ultraviolet reveal a transit signature that is much deeper and longer than in the optical spectrum, an indication that it is surrounded and trailed by a large cloud of gas escaping from the planetary atmosphere. Numerical simulations indicate that in the ultraviolet GJ 436b looks like a giant comet. The authors propose that the gaseous 'tail' is composed mainly of hydrogen atoms and suggest that the exoplanet may have lost 10% of its atmosphere in its early life. Exoplanets orbiting close to their parent stars may lose some fraction of their atmospheres because of the extreme irradiation1,2,3,4,5,6. Atmospheric mass loss primarily affects low-mass exoplanets, leading to the suggestion that hot rocky planets7,8,9 might have begun as Neptune-like10,11,12,13,14,15,16, but subsequently lost all of their atmospheres; however, no confident measurements have hitherto been available. The signature of this loss could be observed in the ultraviolet spectrum, when the planet and its escaping atmosphere transit the star, giving rise to deeper and longer transit signatures than in the optical spectrum17. Here we report that in the ultraviolet the Neptune-mass exoplanet GJ 436b (also known as Gliese 436b) has transit depths of 56.3 ± 3.5% (1σ), far beyond the 0.69% optical transit depth. The ultraviolet transits repeatedly start about two hours before, and end more than three hours after the approximately one hour optical transit, which is substantially different from one previous claim6 (based on an inaccurate ephemeris). We infer from this that the planet is surrounded and trailed by a large exospheric cloud composed mainly of hydrogen atoms. We estimate a mass-loss rate in the range of about 108–109 grams per second, which is far too small to deplete the atmosphere of a Neptune-like planet in the lifetime of the parent star, but would have been much greater in the past.
464 citations
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TL;DR: It is suggested that EEG microstates represent a promising neurophysiological tool for understanding and assessing brain network dynamics on a millisecond timescale in health and disease.
464 citations
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TL;DR: It is proposed that Plk1 is an important target of the DNA damage checkpoint, enabling cell-cycle arrests at multiple points in G2 and mitosis, and blocking mitotic exit.
Abstract: Polo-like kinases (PLKs) have an important role in several stages of mitosis. They contribute to the activation of cyclin B/Cdc2 and are involved in centrosome maturation and bipolar spindle formation at the onset of mitosis. PLKs also control mitotic exit by regulating the anaphase-promoting complex (APC) and have been implicated in the temporal and spatial coordination of cytokinesis. Experiments in budding yeast have shown that the PLK Cdc5 may be controlled by the DNA damage checkpoint. Here we report the effects of DNA damage on Polo-like kinase-1 (Plk1) in a variety of human cell lines. We show that Plk1 is inhibited by DNA damage in G2 and in mitosis. In line with this, we show that DNA damage blocks mitotic exit. DNA damage does not inhibit the kinase activity of Plk1 mutants in which the conserved threonine residue in the T-loop has been changed to aspartic acid, suggesting that DNA damage interferes with the activation of Plk1. Significantly, expression of these mutants can override the G2 arrest induced by DNA damage. On the basis of these data we propose that Plk1 is an important target of the DNA damage checkpoint, enabling cell-cycle arrests at multiple points in G2 and mitosis.
464 citations
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TL;DR: Preincubation experiments reveal that GTP gamma S blocks the function of acceptor Golgi but not donor Golgi membranes, and a processing step in between vesicle attachment and the actual fusion event seems to be affected.
464 citations
Authors
Showing all 27203 results
Name | H-index | Papers | Citations |
---|---|---|---|
JoAnn E. Manson | 270 | 1819 | 258509 |
Joseph L. Goldstein | 207 | 556 | 149527 |
Kari Stefansson | 206 | 794 | 174819 |
David Baltimore | 203 | 876 | 162955 |
Mark I. McCarthy | 200 | 1028 | 187898 |
Michael S. Brown | 185 | 422 | 123723 |
Yang Gao | 168 | 2047 | 146301 |
Napoleone Ferrara | 167 | 494 | 140647 |
Marc Weber | 167 | 2716 | 153502 |
Alessandro Melchiorri | 151 | 674 | 116384 |
Andrew D. Hamilton | 151 | 1334 | 105439 |
David P. Strachan | 143 | 472 | 105256 |
Andrew Beretvas | 141 | 1985 | 110059 |
Rainer Wallny | 141 | 1661 | 105387 |
Josh Moss | 139 | 1019 | 89255 |