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Envirosciences is developing an integrated multi-parameter low-cost monitoring station encompassing the geohazard and geophysical community needs. It consists in integrating co-located sensors ((meteorology, seismology, GNSS) on the same data acquisition card with modular configurations compatible with the EPOS - European Plate Observing System- specifications (sensor type, data sampling, noise level, data and metadata format). On-line data dissemination sand on-demand processing services are further being developed in order to propose advanced products such as GNSS position time series, advanced hydro-meteorological variables and seismic/micro-seismic catalogues.A dense network of 45 stations is currently being implemented in the Western and Central Pyrenees (South France). The network consists of a seismological, meteorological and geodetic (GNSS) antennas. The measurement network is semi-permanent with at least ten years of observation. It will allow to create catalogues of hydro-geomorphological and tectonic events, to document Pyrenean tectonic uplift, and to better constrain local micro-meteorology from the valley bottoms to the summit ridges (by combining co-localised measurements of classic meteorological parameters - wind, temperature, pressure, humidity, precipitation - and tomography of vertical water vapor profiles from GNSS delays).The objective of the presentation is to present the technological development of the station which combines several types of sensors (2 Hz seismometers, dual-frequency GNSS receivers and meteorological stations), a high-frequency geophysical digitization module, a communication module (WiFi or4G) and a power supply module (by solar energy or 220V). Softwares to control the station have been created, as well as software to supervise the database and codes to interpret the measurements.We will further present the processing worklows and the time series of data acquired since November 2022 on 8 measurement stations already deployed in the Pyrenees. By the end of 2023, the full network of 45 autonomous real-time stations will be deployed with inter-station distances of around 5 km.

Increased predation risk or avoidance of wildlife underpasses by small mammals have been highlighted. To overcome this problem and to provide these species with an opportunity to safely cross road-crossing structures, we previously designed an Anti-Predation Tube (APT). The features (shape and size) of this device have been tested under laboratory conditions and its use by captive European hamsters (Cricetus cricetus) has been validated. In this study, we investigate both the enrichment and anti-predation functions of the APT for hamsters in an actual underpass. To do so, we built two small enclosures of 6 m2 at both extremities of an underpass and cross-manipulated the presence of the APT and a predator of hamsters, the European ferret. Our results show that the APT does not act as an enrichment, as it did not increase the crossing frequency of hamsters in the absence of the predator. However, it acts as an anti-predation device, since, in the presence of the ferret, male hamsters crossed more than 10 times as much when the APT was present inside the underpass than when it was not. We therefore recommend implementing the APT as a conservation measure to upgrade wildlife underpasses while conducting surveys to investigate how the presence of the APT influences the crossing of other small mammals and wildlife.

The period of emancipation in seabirds, when juveniles change from a terrestrial existence to a life at sea, is associated with many challenges. Apart from finding favourable foraging sites, they have to develop effective prey search patterns and physiological capacities that enable them to capture sufficient prey to meet their energetic needs. Animals that dive to forage, such as king penguins (Aptenodytes patagonicus), need to acquire an adequate breath-hold capacity, allowing them to locate and capture prey at depth. To investigate the ontogeny of their dive capacity and foraging performance, we implanted juvenile king penguins before their first departure to sea and also adult breeders with a data-logger recording pressure and temperature. We found that juvenile king penguins possess a remarkable dive capacity when leaving their natal colony, enabling them to conduct dives in excess of 100 m within their first week at sea. Despite this, juvenile dive/foraging performance, investigated in relation to dive depth, remained below the adult level throughout their first year at sea, probably reflecting physiological limitations as a result of incomplete maturation. A significantly shallower foraging depth of juveniles, particularly during their first 5 months at sea, could also indicate differences in foraging strategy and targeted prey. The initially greater wiggle rate suggests that juveniles fed opportunistically and also targeted different prey from adults and/or that many of the wiggles of juveniles reflect unsuccessful prey-capture attempts, indicating a lower foraging proficiency. After 5 months, this difference disappeared, suggesting sufficient physical maturation and improvement of juvenile foraging skills.

International audience; Agriculture intensification, marked by the generalization of crop monoculture, by the increase in plot size and by the reduction of plant diversity, has led to huge decline in wildlife in European farmlands. In such habitat, research has long been biased towards birds and invertebrates, while very few studies have investigated the effect on small mammals. Considering the European hamster, Cricetus cricetus, we therefore review the different techniques that can be used to investigate the impact of environmental changes and conservation measures in small and endangered wild mammals. We suggest that only a multidisciplinary approach will allow exploration of these effects, combining experimental laboratory work on captive-bred animals with the monitoring of wild individuals. In particular, individual energy balance has to be investigated and measured as accurately as possible, through either biochemical or bio-logging techniques. It is, indeed, the most affected physiological trait in a changing environment, as it determines both the reproductive output and the survival of the individual. We also discuss the inconvenience of capture-release approaches for such an endangered species and emphasize the disturbance that experimental protocols could impose on the hamster.

The tissue factor pathway inhibitor-2 (TFPI-2) is a Kunitz-type serine-protease inhibitor which is expressed in atherosclerotic plaques. Epigenetic regulation of the TFPI-2 gene, through methylation of CpG islands, has been advocated in cancer. We hypothesized that TFPI-2 gene methylation could regulate TFPI-2 expression in atherosclerosis.We used Methylation Specific PCR (MSP) and pyrosequencing in order to identify 18 CpG of the TFPI-2 promoter, in 59 carotid atherosclerotic plaques and 26 control mammary arteries.MSP showed methylation of the TFPI-2 gene (MSP+) in 16 plaques (27%), while no methylation (MSP-) was found in control arteries. Pyrosequencing confirmed that MSP+ plaques presented higher methylation levels than MSP- ones and arteries (p=0.03 and 0.01). Moreover, the TFPI-2 mRNA levels were lower in methylated plaques than in unmethylated ones and than in arteries (p=0.04 and0.0001). The methylated plaques contained less lipids and macrophage infiltration than unmethylated ones. Their TFPI-2 immunoreactivity was mainly detected in the macrophages located in the media on the adventitial side, rather than in the lipid-rich core.Methylation of the TFPI-2 gene takes place in atherosclerotic plaques and is associated with decreased TFPI-2 expression. The place of this process in atherosclerosis progression remains to be investigated.

Dietary segregation of sympatric seabirds in the Southern Ocean is partly linked to differences in their foraging techniques. We have investigated the activity of giant petrels (Macronectes spp.) in a king penguin (Aptenodytes patagonicus) colony day and night during the austral winter of 2001 on the Crozet Islands. Using an automatic identification system and an infrared video camera, we followed 15 petrels tagged with micro transponders. Our data show that giant petrels predate king penguin chicks during the night. The activity of giant petrels is even slightly higher during nighttime than during the day. In addition, our data show a higher nocturnal activity by northern giant petrels (M. halli) than by southern giant petrels (M. giganteus). These unexpected results raise questions concerning visual adaptations to nocturnal foraging in giant petrels and their potential impact on the sleep, vigilance and creching behavior of penguin chicks.

Le Tissue Factor Pathway Inhibitor-2 (TFPI-2) est un inhibiteur de sérineprotéase de type Kunitz exprimé dans la plaque d’athérosclérose. Le TFPI-2 y présenterait un effet athéroprotecteur en neutralisant les métalloprotéases matricielles (MMP). Le promoteur du gène du TFPI-2 présente plusieurs ilôts CpG dont l’hyperméthylation est associée à une diminution de son expression. Cette régulation épigénétique de l’expression du TFPI-2 a été mise en évidence dans la cancer mais n’a pas encore été étudiée dans l’athérosclérose. L’objectif de ce travail a été d’étudier la méthylation du gène du TFPI-2 dans l’athérosclérose carotidienne avec ses conséquences sur l’expression du transcrit TFPI-2. Le statut de méthylation du gène du TFPI-2 a également été confronté aux données cliniques des patients et à la morphologie des plaques.La méthylation de 18 motifs CpG du promoteur du TFPI-2 a été étudiée par Methylation Specific PCR (MSP) et pyroséquençage (PyroMark MD, Biotage) dans 59 plaques d’athérosclérose carotidienne et 26 artères mammaires contrôle.Seize plaques (27 %) étaient retrouvées méthylées par MSP (groupe MSP+) alors qu’aucune artère mammaire ne l’était. Le pyroséquençage a confirmé que les plaques MSP+ présentaient des niveaux de méthylation significativement plus élevés que les plaques MSP- mais aussi que les artères (p = 0,03 et 0,01, respectivement). Le niveau de transcrit TFPI-2 était significativement plus bas dans les plaques méthylées que dans les non méthylées et que dans les artères (p=0,04 et < 0,0001, respectivement). Les facteurs de risque cardiovasculaire, les accidents ischémiques cérébraux mais également l’activité MMP-9 des plaques n’étaient pas différents entre les échantillons méthylés et non méthylés. Cependant, les plaques méthylées présentaient des infiltrats lipidiques et macrophagiques réduits par rapports aux plaques non méthylées.Cette étude démontre pour la première fois que l’expression du TFPI-2 peut être régulée par hyperméthylation de son gène dans l’athérosclérose. L’hyperméthylation du gène du TFPI-2 est associée à une diminution de l’expression de son transcrit mais également à des plaques morphologiquement moins sévères. L’impact de la méthylation du TFPI-2 sur la régulation des MMP et sur la fragilité de la plaque d’athérosclérose reste à déterminer.