Effects of Thermal Stress on the Gut Microbiome of Juvenile Milkfish (Chanos chanos)

Milkfish, an important aquaculture species in Asian countries, are traditionally cultured in outdoor-based systems. There, they experience potentially stressful fluctuations in environmental conditions, such as temperature, eliciting changes in fish physiology. While the importance of the gut microbiome for the welfare and performance of fish has been recognized, little is known about the effects of thermal stress on the gut microbiome of milkfish and its interactions with the host's metabolism. We investigated the gut microbiome of juvenile milkfish in a thermal stress experiment, comparing control (26 degrees C) and elevated temperature (33 degrees C) treatments over three weeks, analyzing physiological biomarkers, gut microbiome composition, and tank water microbial communities using 16S amplicon sequencing. The gut microbiome was distinct from the tank water and dominated by Cetobacterium, Enterovibrio, and Vibrio. We observed a parallel succession in both temperature treatments, with microbial communities at 33 degrees C differing more strongly from the control after the initial temperature increase and becoming more similar towards the end of the experiment. As proxy for the fish's energy status, HSI (hepatosomatic index) was correlated with gut microbiome composition. Our study showed that thermal stress induced changes in the milkfish gut microbiome, which may contribute to the host's habituation to elevated temperatures over time

Stopping of energetic sulfur and bromine ions in dense hydrogen plasma

The concepts of communicative space, media sphere and public sphere are sometimes used like synonyms one of the other. However, according to us, they are three different concepts: public sphere and media sphere are two distinct spaces symbolic systems which, both, are anchored in communicative spac

Morphometric discrimination of two sympatric sibling species in the Palaearctic region, Culicoides obsoletus Meigen and C-scoticus Downes & Kettle (Diptera: Ceratopogonidae), vectors of bluetongue and Schmallenberg viruses

Background Some Palaearctic biting midge species (subgenus Avaritia) have been implicated as vectors of bluetongue virus in northern Europe. Separation of two species (C. obsoletus and C. scoticus) is considered difficult morphologically and, often, these female specimens are grouped in entomological studies. However, species-specific identification is desirable to understand their life history characteristics, assess their roles in disease transmission or measure their abundance during arboviral outbreaks. This study aims to investigate whether morphometric identification techniques can be applied to female C. obsoletus and C. scoticus individuals trapped at different geographical regions and time periods during the vector season. Methods C. obsoletus and C. scoticus were collected using light-suction traps from the UK, France and Spain, with two geographical locations sampled per country. A total of 759 C. obsoletus/C. scoticus individuals were identified using a molecular assay based on the cytochrome c oxidase subunit I gene. Fifteen morphometric measurements were taken from the head, wings and abdomen of slide-mounted specimens, and ratios calculated between these measurements. Multivariate analyses explored whether a combination of morphometric variables could lead to accurate species identification. Finally, Culicoides spp. collected in France at the start, middle and end of the adult vector season were compared, to determine whether seasonal variation exists in any of the morphometric measurements. Results The principal component analyses revealed that abdominal characteristics: length and width of the smaller and larger spermathecae, and the length of the chitinous plates and width between them, are the most reliable morphometric characteristics to differentiate between the species. Seasonal variation in the size of each species was observed for head and wing measurements, but not abdominal measurements. Geographical variation in the size of Culicoides spp. was also observed and is likely to be related to temperature at the trapping sites, with smaller individuals trapped at more southern latitudes. Conclusions Our results suggest that female C. obsoletus and C. scoticus individuals can be separated under a stereomicroscope using abdominal measurements. Although we show the length and width of the spermathecae can be used to differentiate between the species, this can be time-consuming, so we recommend undertaking this using standardized subsampling of catches. (Résumé d'auteur

Three-Terminal Junctions operating as mixers, frequency doublers and detectors: A broad-band frequency numerical and experimental study at room temperature

The frequency response of nanometric T- and Y-shaped three-terminal junctions (TTJs) is investigated experimentally and numerically. In virtue of the parabolic down-bending of the output voltage of the central branch obtained at room temperature under a push-pull fashion input, we analyze: the low-frequency performance (<1 MHz) of TTJs operating as mixers, their RF capability as doublers up to 4 GHz and detection at 94 GHz. Special attention is paid to the impedance matching and cut-off frequency of the measurement set-up. The numerical study is done by means of Monte Carlo simulations. We illustrate the intrinsic functionality of the device as frequency doubler or rectifier up to THz. The role of the width of the central branch on the highfrequency response is also explored, finding different cut-off frequencies for doubling and detection as a consequence of the diverse working principles of both mechanisms and the particular geometry of the TTJs.ROOTHz (FP7-243845

Evaluation des projets de télématique routière : contribution des programmes européens "DRIVE" et "4ème PCRD" à la réflexion méthodologique

Ce document a été rédigé par Eric Mouline, du CETE de l’Est, avec des contributions des membres du groupe de suivi CERTU-SETRA. Il s’attache dans un premier temps à définir ce que recouvre le terme évaluation, à préciser quelles sont les différentes « catégories » d’évaluation que l’on peut être amené à conduire, et enfin quelles sont les différentes étapes que l’on rencontre dans tout travail d’évaluation. La suite du document présente les différents apports méthodologiques notables à travers les différents programmes de recherche européens. La méthode d’évaluation socio-économique élaborée lors du projet EVA, très utile quant à la définition de critères d’évaluation « universels » ainsi que la méthode des « 12 ETAPES », ensemble de recommandations facilitant les évaluations nécessitant des essais de terrain, issue du projet FIELD TRIALS, deux projets du programme DRIVE I sont tout d’abord exposées. Le rapport se consacre ensuite à l’étude des travaux menés lors du programme DRIVE II et présente les résultats du projet CORD, qui a élaboré un certain nombre de recommandations adaptées à chacun des thèmes explorés par les projets DRIVE II, ainsi que du projet HOPES, proposant des recommandations utiles à l’appréciation de l’impact des projets en termes de sécurité. Enfin, l’actuel programme cadre de Recherche et Développement est à son tour étudié, et les apports du projet CONVERGE, notamment le guide conçu en 1996 destiné à aider les projets dans leurs tâches d’évaluation, ainsi que de l’étude APAS/ROAD 3 consacrée par la Direction Générale des Transports (DGVII) à l’évaluation sont présentés

Evaluation des projets de télématique routière : contribution des programmes européens "DRIVE" et "4ème PCRD" à la réflexion méthodologique

Ce document a été rédigé par Eric Mouline, du CETE de l’Est, avec des contributions des membres du groupe de suivi CERTU-SETRA. Il s’attache dans un premier temps à définir ce que recouvre le terme évaluation, à préciser quelles sont les différentes « catégories » d’évaluation que l’on peut être amené à conduire, et enfin quelles sont les différentes étapes que l’on rencontre dans tout travail d’évaluation. La suite du document présente les différents apports méthodologiques notables à travers les différents programmes de recherche européens. La méthode d’évaluation socio-économique élaborée lors du projet EVA, très utile quant à la définition de critères d’évaluation « universels » ainsi que la méthode des « 12 ETAPES », ensemble de recommandations facilitant les évaluations nécessitant des essais de terrain, issue du projet FIELD TRIALS, deux projets du programme DRIVE I sont tout d’abord exposées.Le rapport se consacre ensuite à l’étude des travaux menés lors du programme DRIVE II et présente les résultats du projet CORD, qui a élaboré un certain nombre de recommandations adaptées à chacun des thèmes explorés par les projets DRIVE II, ainsi que du projet HOPES, proposant des recommandations utiles à l’appréciation de l’impact des projets en termes de sécurité.Enfin, l’actuel programme cadre de Recherche et Développement est à son tour étudié, et les apports du projet CONVERGE, notamment le guide conçu en 1996 destiné à aider les projets dans leurs tâches d’évaluation, ainsi que de l’étude APAS/ROAD 3 consacrée par la Direction Générale des Transports (DGVII) à l’évaluation sont présentés

INVESTIGATION OF THE TRANSMISSION AND STOPPING OF LIGHT IONS PASSING THROUGH A PLASMA TARGET

Transmission and energy losses of 2 MeV/u Carbon and Sulphur beams passing through a plasma target, have been extensively investigated. A hydrogen plasma ignited by an electrical discharge was coupled to the Orsay Tandem beam accelerator. Fluctuations in beam transmission have been observed and attributed to a magnetic focusing effect generated during the plasma evolution. Energy loss measurements were performed on the basis of time of flight techniques and indicate an enhanced stopping power of the plasma relative to its cold matter equivalent