Cosmological constraints on decaying axion-like particles: a global analysis

Axion-like particles (ALPs) decaying into photons are known to affect a wide range of astrophysical and cosmological observables. In this study we focus on ALPs with masses in the keV–MeV range and lifetimes between 10$^4$ and 10$^{13}$ seconds, corresponding to decays between the end of Big Bang Nucleosynthesis and the formation of the Cosmic Microwave Background (CMB). Using the CosmoBit module of the global fitting framework GAMBIT, we combine state-of-the-art calculations of the irreducible ALP freeze-in abundance, primordial element abundances (including photodisintegration through ALP decays), CMB spectral distortions and anisotropies, and constraints from supernovae and stellar cooling. This approach makes it possible for the first time to perform a global analysis of the ALP parameter space while varying the parameters of ΛCDM as well as several nuisance parameters. We find a lower bound on the ALP mass of around m$_a$ > 300 keV, which can only be evaded if ALPs are stable on cosmological timescales. Future observations of CMB spectral distortions with a PIXIE-like mission are expected to improve this bound by two orders of magnitude

Cosmological constraints on decaying axion-like particles: a global analysis

Axion-like particles (ALPs) decaying into photons are known to affect a wide range of astrophysical and cosmological observables. In this study we focus on ALPs with masses in the keV-MeV range and lifetimes between 10$^4$ and 10$^{13}$ seconds, corresponding to decays between the end of Big Bang Nucleosynthesis and the formation of the Cosmic Microwave Background (CMB). Using the CosmoBit module of the global fitting framework GAMBIT, we combine state-of-the-art calculations of the irreducible ALP freeze-in abundance, primordial element abundances (including photodisintegration through ALP decays), CMB spectral distortions and anisotropies, and constraints from supernovae and stellar cooling. This approach makes it possible for the first time to perform a global analysis of the ALP parameter space while varying the parameters of ΛCDM as well as several nuisance parameters. We find a lower bound on the ALP mass of around m$_a$>300keV, which can only be evaded if ALPs are stable on cosmological timescales. Future observations of CMB spectral distortions with a PIXIE-like mission are expected to improve this bound by two orders of magnitude

An Automated Approach to map a French terminology to UMLS

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Strategies for the Identification of Bioactive Neuropeptides in Vertebrates

International audienceNeuropeptides exert essential functions in animal physiology by controlling e.g., reproduction, development, growth, energy homeostasis, cardiovascular activity and stress response. Thus, identification of neuropeptides has been a very active field of research over the last decades. This review article presents the various methods used to discover novel bioactive peptides in vertebrates. Initially identified on the basis of their biological activity, some neuropeptides have also been discovered for their ability to bind/activate a specific receptor or based on their biochemical characteristics such as C-terminal amidation which concerns half of the known neuropeptides. More recently, sequencing of the genome of many representative species has facilitated peptidomic approaches using mass spectrometry and in silico screening of genomic libraries. Through these different approaches, more than a hundred of bioactive neuropeptides have already been identified in vertebrates. Nevertheless, researchers continue to find new neuropeptides or to identify novel functions of neuropeptides that had not been detected previously, as it was recently the case for nociceptin

RNA Sequencing technology will help deciphering the morphogenesis mechanisms in the model diatom Phaeodactylum tricornutum

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RNA Sequencing technology will help deciphering the morphogenesis mechanisms in the model diatom Phaeodactylum tricornutum

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Etude des mécanismes de morphogenèse chez la diatomée modèle Phaeodactylum tricornutum par séquençage d’ARN à haut débit (RNA-Seq)

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Etude des mécanismes de morphogenèse chez la diatomée modèle Phaeodactylum tricornutum par séquençage d’ARN à haut débit (RNA-Seq)

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Elucidation of the morphogenesis mechanisms in the diatom P. tricornutum using RNA sequencing technology

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RNA-seq : a new tool to study Phaeodactylum tricornutum morphogenesis

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