Demographic profiles and environmental drivers of variation relate to individual breeding state in a long-lived trans-oceanic migratory seabird, the Manx shearwater

Understanding the points in a species breeding cycle when they are most vulnerable to environmental fluctuations is key to understanding interannual demography and guiding effective conservation and management. Seabirds represent one of the most threatened groups of birds in the world, and climate change and severe weather is a prominent and increasing threat to this group. We used a multi-state capture-recapture model to examine how the demographic rates of a long-lived trans-oceanic migrant seabird, the Manx shearwater Puffinus puffinus, are influenced by environmental conditions experienced at different stages of the annual breeding cycle and whether these relationships vary with an individual's breeding state in the previous year (i.e., successful breeder, failed breeder and non-breeder). Our results imply that populations of Manx shearwaters are comprised of individuals with different demographic profiles, whereby more successful reproduction is associated with higher rates of survival and breeding propensity. However, we found that all birds experienced the same negative relationship between rates of survival and wind force during the breeding season, indicating a cost of reproduction (or central place constraint for non-breeders) during years with severe weather conditions. We also found that environmental effects differentially influence the breeding propensity of individuals in different breeding states. This suggests individual spatio-temporal variation in habitat use during the annual cycle, such that climate change could alter the frequency that individuals with different demographic profiles breed thereby driving a complex and less predictable population response. More broadly, our study highlights the importance of considering individual-level factors when examining population demography and predicting how species may respond to climate change

Demographic profiles and environmental drivers of variation relate to individual breeding state in a long-lived trans-oceanic migratory seabird, the Manx shearwater.

Understanding the points in a species breeding cycle when they are most vulnerable to environmental fluctuations is key to understanding interannual demography and guiding effective conservation and management. Seabirds represent one of the most threatened groups of birds in the world, and climate change and severe weather is a prominent and increasing threat to this group. We used a multi-state capture-recapture model to examine how the demographic rates of a long-lived trans-oceanic migrant seabird, the Manx shearwater Puffinus puffinus, are influenced by environmental conditions experienced at different stages of the annual breeding cycle and whether these relationships vary with an individual's breeding state in the previous year (i.e., successful breeder, failed breeder and non-breeder). Our results imply that populations of Manx shearwaters are comprised of individuals with different demographic profiles, whereby more successful reproduction is associated with higher rates of survival and breeding propensity. However, we found that all birds experienced the same negative relationship between rates of survival and wind force during the breeding season, indicating a cost of reproduction (or central place constraint for non-breeders) during years with severe weather conditions. We also found that environmental effects differentially influence the breeding propensity of individuals in different breeding states. This suggests individual spatio-temporal variation in habitat use during the annual cycle, such that climate change could alter the frequency that individuals with different demographic profiles breed thereby driving a complex and less predictable population response. More broadly, our study highlights the importance of considering individual-level factors when examining population demography and predicting how species may respond to climate change

Haploinsufficiency of ARFGEF1 is associated with developmental delay, intellectual disability, and epilepsy with variable expressivity

ADP ribosylation factor guanine nucleotide exchange factors (ARFGEFs) are a family of proteins implicated in cellular trafficking between the Golgi apparatus and the plasma membrane through vesicle formation. Among them is ARFGEF1/BIG1, a protein involved in axon elongation, neurite development, and polarization processes. ARFGEF1 has been previously suggested as a candidate gene for different types of epilepsies, although its implication in human disease has not been well characterized. International data sharing, in silico predictions, and in vitro assays with minigene study, western blot analyses, and RNA sequencing. We identified 13 individuals with heterozygous likely pathogenic variants in ARFGEF1. These individuals displayed congruent clinical features of developmental delay, behavioral problems, abnormal findings on brain magnetic resonance image (MRI), and epilepsy for almost half of them. While nearly half of the cohort carried de novo variants, at least 40% of variants were inherited from mildly affected parents who were clinically re-evaluated by reverse phenotyping. Our in silico predictions and in vitro assays support the contention that ARFGEF1-related conditions are caused by haploinsufficiency, and are transmitted in an autosomal dominant fashion with variable expressivity. We provide evidence that loss-of-function variants in ARFGEF1 are implicated in sporadic and familial cases of developmental delay with or without epilepsy

Viral to metazoan marine plankton nucleotide sequences from the Tara Oceans expedition

A unique collection of oceanic samples was gathered by the Tara Oceans expeditions (2009-2013), targeting plankton organisms ranging from viruses to metazoans, and providing rich environmental context measurements. Thanks to recent advances in the field of genomics, extensive sequencing has been performed for a deep genomic analysis of this huge collection of samples. A strategy based on different approaches, such as metabarcoding, metagenomics, single-cell genomics and metatranscriptomics, has been chosen for analysis of size-fractionated plankton communities. Here, we provide detailed procedures applied for genomic data generation, from nucleic acids extraction to sequence production, and we describe registries of genomics datasets available at the European Nucleotide Archive (ENA, www.ebi.ac.uk/ena). The association of these metadata to the experimental procedures applied for their generation will help the scientific community to access these data and facilitate their analysis. This paper complements other efforts to provide a full description of experiments and open science resources generated from the Tara Oceans project, further extending their value for the study of the world's planktonic ecosystems

Mécanismes d inversion dans les émulsions stimulables et réversibles

Nous avons étudié l inversion de phase transitionnelle d émulsions stabilisées par des copolymères diblocs amphiphiles formés d un bloc polystyrène (PS) et d un second bloc de poly(méthacrylate de diméthylamino éthyle) (PDMAEMA) pouvant également contenir des unités styrène. La polymérisation radicalaire contrôlée par transfert d atome nous a permis de synthétiser plusieurs copolymères en variant la masse molaire des chaînes, le rapport des longueurs des deux blocs et la composition du second bloc. En raison de la présence des unités DMAEMA, le pH et/ou la température sont utilisés comme stimuli pour contrôler les propriétés des copolymères adsorbés aux interfaces eau/toluène. En particulier, nous contrôlons la nature et la stabilité des émulsions formées en balayant la séquence émulsions huile dans eau (H/E) - émulsions multiples ou coexistence d émulsions H/E et E/H instables - émulsions eau dans huile (E/H) . De manière originale, notre travail montre pour la première fois que des émulsions multiples stables mais stimulables peuvent être obtenues lors d une inversion de phase transitionnelle. Ces résultats laissent entrevoir des perspectives attrayantes dans le domaine de l encapsulation/libération de principes actifs par des émulsions multiples. D un point de vue fondamental, nous expliquons comment les séquences d émulsions formées dépendent de la nature du copolymère et du pH. Pour cela, nous avons conduit une étude multi-échelle en établissant des corrélations entre la nature de l émulsion formée, les microémulsions et le type d émulsifiant adsorbé à l interface. Les différentes techniques utilisées sont la tensiométrie, la microscopie confocale, la spectroscopie UV, la cryo-MET et la diffusion de neutrons aux petits angles. Nous montrons aussi des résultats originaux qui consistent à sonder la conformation des chaînes adsorbées par réflectivité de neutrons aux interfaces eau/toluène. Les mesures sont réalisées à l aide d une cellule que nous avons spécialement conçue.We studied transitional phase inversion of water/toluene emulsions stabilized by amphiphilic diblock copolymers with one polystyrene (PS) block and a second block consisting of either (dimethylamino)ethyl methacrylate (DMAEMA) unit or DMAEMA and styrene units. Atom transfer radical polymerization was used to synthesize several copolymers with different molar mass, block length ratio and composition of the hydrophilic block. Because of the presence of DMAEMA, pH and/or temperature were used as stimuli to control the properties of adsorbed copolymer chains at the water/toluene interface. More specifically, we exactly control emulsions stability and the sweep of the transitional sequence direct emulsions (O/W) - multiple emulsions or coexistence of O/W and W/O unstable emulsions - inverse emulsions (W/O) . Our work is original by several aspects. It shows for the first time that stable but stimulable multiple emulsions can be prepared within the transitional phase inversion domain separating the domains of inverse and direct emulsions. The results are indeed promising in the domain of encapsulation/release of active species. From a fundamental viewpoint, we explain how the sequence of formed emulsions depends on the copolymer type and pH. We performed a multiscale approach to establish correlations between emulsion kind, microemulsions and type of copolymer adsorbed at interface. To probe the various scales, we used rising and spinning tensiometry, confocal microscopy, UV spectroscopy, cryo-TEM and small angle neutrons scattering. We also presents original results of neutron reflectivity to probe the conformation of chain adsorbed at toluene/water interface. Measurements are achieved in a specially designed cell.PARIS-BIUSJ-Biologie recherche (751052107) / SudocSudocFranceF

Far infrared absorption and terahertz time domain spectroscopy of liquid CS2: experiments and molecular dynamics simulation

International audienc

Multiple Emulsions Controlled by Stimuli-Responsive Polymers

International audienceThe phase inversion of water-toluene emulsions stabilized with a single thermo- and pH-sensitive copolymer occurs through the formation of multiple emulsions. At low pH and ambient temperature, oil in water emulsions are formed which transform into highly stable multiple emulsions at pHs immediately lower than the inversion border. At higher pHs, the emulsion turns into a water in oil one

Le bilan d'une liaison infrarouge dans un environnement domestique

National audience.Lobjectif de notre article est de présenter un bilan d'un système optique sans fil, transmettant de l'infrarouge, dans un environnement domestique. Après une description des principes de base, une étude comparative entre des schémas de modulation d'intensité et de détection directe (IM/DD) est énoncée. Elle permet d'expliciter les performances globales de la liaison en fonction de la puissance de la lumière ambiante. Nous montrons qu'un simple égaliseur associé à la modulation tout ou rien OOK (On Off Keying) aurait, dans certaines circonstances et pour un même débit binaire, des meilleurs résultats que l'OFDM ou encore que l'OFDM/OQAM modifié