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Human Footprint and Forest Disturbance Reduce Space Use of Brown Bears (<i>Ursus arctos</i>) Across Europe
No full textInternational audienceThree-quarters of the planet's land surface has been altered by humans, with consequences for animal ecology, movements and related ecosystem functioning. Species often occupy wide geographical ranges with contrasting human disturbance and environmental conditions, yet, limited data availability across species' ranges has constrained our understanding of how human pressure and resource availability jointly shape intraspecific variation of animal space use. Leveraging a unique dataset of 758 annual GPS movement trajectories from 375 brown bears (Ursus arctos) across the species' range in Europe, we investigated the effects of human pressure (i.e., human footprint index), resource availability and predictability, forest cover and disturbance, and area-based conservation measures on brown bear space use. We quantified space use at different spatiotemporal scales during the growing season (May–September): home range size; representing general space requirements, 10-day long-distance displacement distances, and routine 1-day displacement distances. We found large intraspecific variation in brown bear space use across all scales, which was profoundly affected by human footprint index, vegetation productivity, and recent forest disturbances creating opportunity for resource pulses. Bears occupied smaller home ranges and moved less in more anthropized landscapes and in areas with higher resource availability and predictability. Forest disturbances reduced space use while contiguous forest cover promoted longer daily movements. The amount of strictly protected and roadless areas within bear home ranges was too small to affect space use. Anthropized landscapes may hinder the expansion of small and isolated populations, such as the Apennine and Pyrenean, and obstruct population connectivity, for example between the Dinaric Pindos population and the Alpine or Carpathian population. Our findings call for actions to maintain bear movements across landscapes with high human footprint, for example by maintaining forest integrity, to support viable bear populations and their ecosystem functions
Sustainable Scheduling in Manufacturing: Integrating NSGA-II and Discrete-Event Simulation for Hybrid Flowshop Environments
No full textInternational audienc
Exploration de la spécificité du domaine et des corrélats neuronaux de la méconnaissance de la mémoire dans la maladie d'Alzheimer
No full textInternational audiencePatients with Alzheimer's disease (AD) are less accurate than controls to predict their episodic performance, but they are as accurate as controls to predict their semantic performance. However, the dissociation between episodic and semantic metamemory had never been tested directly in the same patients. This study aimed to explore the dissociation between episodic and semantic metamemory in AD using the feeling-of-knowing paradigm. In addition, we investigated the link between memory awareness and resting-state cerebral glucose metabolism and gray matter density, in episodic and semantic tasks independently. Data from 50 patients with AD were compared to data from 30 healthy controls. Results showed that patients with AD had more difficulties to predict their recognition in the episodic task than in the semantic task, while this difference was smaller in controls. However, this dissociation was only shown with a measure of absolute accuracy, but not with a measure of relative accuracy. Lack of awareness in the episodic task was associated with hypometabolism in right frontoparietal areas in patients with AD, while semantic metamemory was associated with gray matter integrity in the left angular gyrus. The consequence of metacognitive bias and memory status on metamemory judgments are discussed.Les patients atteints de la maladie d'Alzheimer (MA) sont moins précis que les témoins pour prédire leurs performances épisodiques, mais ils sont aussi précis que les témoins pour prédire leurs performances sémantiques. Cependant, la dissociation entre la métamémoire épisodique et la métamémoire sémantique n'a jamais été testée directement chez les mêmes patients. Cette étude visait à explorer la dissociation entre la métamémoire épisodique et la métamémoire sémantique dans la MA en utilisant le paradigme de feeling-of-knowing. En outre, nous avons étudié le lien entre la conscience de la mémoire et le métabolisme cérébral du glucose et la densité de la matière grise à l'état de repos, dans les tâches épisodiques et sémantiques de manière indépendante. Les données de 50 patients atteints de la maladie d'Alzheimer ont été comparées à celles de 30 témoins sains. Les résultats ont montré que les patients atteints de la maladie d'Alzheimer avaient plus de difficultés à prédire leur reconnaissance dans la tâche épisodique que dans la tâche sémantique, alors que cette différence était plus faible chez les témoins. Cependant, cette dissociation a été mise en évidence avec une mesure de la précision absolue, mais pas avec une mesure de la précision relative. Le manque de conscience dans la tâche épisodique a été associé à un hypométabolisme dans les zones frontopariétales droites chez les patients atteints de la MA, tandis que la métamémoire sémantique a été associée à l'intégrité de la matière grise dans le gyrus angulaire gauche. Les conséquences des biais métacognitifs et de l'état de la mémoire sur les jugements de métamémoire sont discutées
Antiprotons and Elementary Particles over a Solar Cycle: Results from the Alpha Magnetic Spectrometer
No full textInternational audienceWe present results over an 11-year Solar cycle of cosmic antiprotons based on 1.1×106 events in the rigidity range from 1.00 to 41.9 GV. The p¯ fluxes exhibit distinct properties. The magnitude of the p¯ flux temporal variation is significantly smaller than those of p, e-, and e+. A hysteresis between the p¯ fluxes and the p fluxes is observed, whereas the p¯ and e- fluxes show a linear correlation. With a model-independent analysis, we found a universal relation between the shape of the rigidity spectrum and the magnitude of flux temporal variation over an 11-year Solar cycle for both positively and negatively charged particles. The simultaneous results on p¯ and p, e-, and e+ provide unique information for understanding particle transport in the Solar System as a function of mass, charge, and spectral shape
Rapport annuel des services du Centre de Données Sismologique Epos-France, année 2024
No full textThe Epos-France Seismological Data Center publishes the annual report on service usage for 2024. It contains KPI for the services supported
Evidence for decays
No full textInternational audienceThe first evidence for the decay is obtained using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb , at centre-of-mass energies of 7, 8 and 13 Tev. Here, the meson represents any of the three excited charm mesons , , and . The signal is measured with a significance of 3.5 , including systematic uncertainties. The combined branching fraction , where denotes both and contributions, is measured to be , where the last uncertainty reflects that of the branching fraction of the normalisation channel . The ratio between the tauonic and muonic semileptonic decays, with the latter taken from world average values, is also determined and found to be
A methodology for assessing environmental impact of building integrated PV in low carbon footprint electricity generation context
No full textInternational audienceWith the growing interest in renewable energy to mitigate climate change, photovoltaics are increasingly relevant due to their limited carbon emissions in the use phase. This study focuses on integrating photovoltaic technologies in countries with low-carbon electricity mixes, specifically the cases of France and Norway. It presents a comprehensive methodology assessing the environmental impact of PV technologies and their application in a French and a Norwegian building. The research includes a case study of a single-family house, modeled in TRNSYS for dynamic thermal systems simulation, operating in both locations. The photovoltaic panels' life cycle assessment is conducted using the SimaPro software and a functional unit of 1 kWh from mono-crystalline panels with an expected service life of 25 years. Such analysis aims to evaluate the environmental impact through key performance indicators during the life span of the photovoltaic panel, from cradle to use with a focus on the raw material use, manufacturing processes, transportation, use phase replacements and electricity production. The indicators analysed are global warming potential, cumulative energy demand (non-renewable, fossil), energy payback time and energy return on energy invested. The study also explores the impact of different manufacturing, transportation and installation scenarios of the photovoltaic panels, including a 100% European low carbon footprint electricity mix. In summary, the findings demonstrate that in countries with low-carbon electricity production, the use of photovoltaic panels presents a favorable outcome in terms of global warming potential for the French case (25-38.6 g e/kWh), regardless of their place of manufacturing. For the Norwegian scenarios (spanning 29.5-45.6 g e/kWh), the life cycle benefit in terms of emission reductions is only evident if the panels are locally produced in Europe. This conclusion is based on electricity from the photovoltaic installation modeled to replace the Norwegian production mix of electricity. Thus, the geographical system boundaries in relation to the replaced electricity is an important parameter. Cumulative energy demand (non-renewable, fossil) was found to vary between 0.34 MJ/kWh and 0.44 MJ/kWh, the Norwegian scenarios consistently showing higher numbers than the French. Energy payback times of the mono crystalline photovoltaic panel ranged between 0.75 to 0.97 years depending on the solar potential of the installation place and the scenarios of manufacturing
7000 ans d'histoire de la végétation et des activités agro-pastorales sur le plateau des Glières (Alpes du Nord françaises)
No full textInternational audienceLe paysage du Plateau des Glières, aujourd'hui marqué par les pratiques pastorales et récréatives, résulte d'une longue histoire d'interactions entre les écosystèmes, l'homme et le climat. L'analyse des carottes prélevées dans la tourbière des Glières a permis de reconstruire les dynamiques de végétations et des activités humaines dans le secteur régional et local au cours des 7000 dernières années, grâce à l'analyse combinée du pollen, des champignons coprophiles et des macro-charbons. L'histoire de la végétation des Glières s'avère être majoritairement forestière, du fait de son altitude, bien que plusieurs phases d'anthropisation soient également enregistrées depuis la fin du Néolithique
A Geometric View on Crossing-Symmetric Dispersion Relations
No full textInternational audienceWe introduce a general framework for constructing dispersion relations using crossing-symmetric variables, leading to infinitely many distinct representations of the 2-to-2 scattering amplitude of identical scalars. Classical formulations such as the Auberson-Khuri crossing-symmetric dispersion relations (CSDRs), the Mahoux-Roy-Wanders relations, and the local CSDR, as well as fixed-t dispersion relations emerge as special cases. Within this setting we re-derive the null constraints from a geometric perspective. Finally, we present, for the first time, an explicit extension of Roy-like equations that remain valid at arbitrarily high energies, relying only on the rigorously established analyticity domain of scattering amplitudes
What is the most suitable medicine ball mass for assessing maximal upper-extremity power in the seated single-arm horizontal push test?
No full textInternational audienceIntroduction. Different medicine ball (MB) masses are used for the unilateral MB push to indirectly determine upper-extremity power. This study aimed to identify the most suitable MB mass for assessing maximal upper-extremity power through the seated single-arm horizontal push test (SSAHPT).Methods. Thirty-four athletes performed the SSAHPT with three different MB masses (1 kg, 3 kg, and 5 kg) and the unilateral ballistic bench press test. For each limb, the SSAHPT distance was determined, and the maximal power (Pmax) and force-velocity profile (SFv) were extracted from the unilateral bench press test.Results. For the 1-kg and 3-kg MB, SSAHPT performance variation was explained by the variations of Pmax and Dominance (R2 = 0.82–0.86), with the effect of Pmax about 5.5 times greater than the effect of Dominance. For the 5-kg MB mass, SSAHPT performance variation was explained by the variations of Pmax, Dominance, and SFv (R2 = 0.85). The effect of Pmax was 5.3 and 1.6 times greater than the effect of Dominance and SFv, respectively.Conclusion. To limit the involvement of the athlete's force-velocity profile in SSAHPT performance with a 5-kg MB mass, it is advisable to use either a 1-kg or 3-kg MB mass when SSAHPT is employed to reflect maximal upper-extremity power