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Is non-local communication really impossible?
No full textThis paper shows the possibility of non-local communication between two entangled, spacelike separated sub-systems. More specifically, it is shown that if there exist (at least) two non-commuting observables respectively defined on these two sub-systems then, for some entangled state of the global system, the probability distribution of the outcomes of measurements performed in one of its parts is changed by the actions that have been performed in the other one. This causal dependency, which includes that of the settings, makes possible a nonlocal exchange of information between the parties
Du micro au macro : analyser les supports et les productions d'élèves pour enseigner une chimie durable
No full textInternational audienc
Synthesised database of wild bee and hoverfly records in Europe
No full textInternational audienceWild bees (Hymenoptera: Anthophila) and hoverflies (Diptera: Syrphidae), the two major groups of insect pollinators, are undergoing alarming declines worldwide, including Europe. The lack of accessible and verified spatial and temporal occurrence records currently challenges efforts to understand and mitigate this decline. Here, we compiled datasets from diverse sources, including taxonomists, national experts, public repositories, museum collections, published literature, verified open-access platforms, and aggregated datasets from previous European projects. The collected data were standardised, cleaned and validated by taxonomists and national experts. This collective effort resulted in two databases comprising more than 4.34 million and 1.04 million records for wild bees and hoverflies, respectively. The databases cover 97% of the European bee fauna (2,083 species out of 2,138 recorded in Europe) and 97% of the European hoverfly fauna (886 species out of 913 recorded in Europe). These standardised databases constitute essential resources for future assessments of status and trends, habitat associations, and other research and conservation initiatives to protect and understand wild pollinators on the European continent
Rethinking glacial cirque evolution: an exploratory case study of interglacial sediment contributions in Quaternary cirques widening (Vestfirðir, Iceland)
No full textInternational audienceThe classical paradigm of glacial cirque evolution, centered on glacial erosion, often underestimates the contribution of interglacial periods. This study quantitatively assesses the role of paraglacial (rock-slope failures, RSF) and periglacial (scree) processes in the morphogenesis of eight Quaternary cirques in Vestfirðir, Iceland. The methodology relies on building a Holocene reference model by quantifying the current volumes of cirques and their internal RSF (61.5%) and scree deposits (38.5%). This model is then extrapolated over 22 Quaternary interglacial cycles. The Quaternary extrapolation reveals a continuum of morphogenic controls: in smaller cirques, interglacial processes can account for the majority of the excavated volume, whereas larger cirques are dominated by glacial erosion. This highlights a scale effect. These findings challenge the traditional glacial-centric view and support a positive-feedback model where glacial and interglacial processes act in a synergistic relationship, driving cirque widening over successive climatic cycles. The study thus re-evaluates the role of interglacial slope dynamics as a crucial, and sometimes primary, agent in cirque development
Evaluation of lung VEGF-A transduction during hyperoxia-induced injury in rats
No full textBackground: Since Vascular Endothelial Growth Factor (VEGF) is a main factor for endothelial survival, we evaluated whether VEGF transduction could ameliorate hyperoxiainduced injury, which is associated with predominant endothelial injury. Methods and Results: Transduction (induced 48 hours before hyperoxic exposure) using adenoviral vector (Ad.) for VEGF (10 10 viral particles [VP]) increased moderately survival under hyperoxia (fraction of inspired oxygen [FIO 2 ] >95%) as compared with Ad.Null (10 10 VP) transduction, whereas VEGF transduction with a lower dose (5.10 9 VP) had no effect. After 48 hours of hyperoxia, Ad.VEGF transduction increased lung VEGF concentration, prevented the diffuse loss of capillary bed and induced patchy areas of endothelial cell proliferation (CD31 immunostaining) with interstitial inflammatory cell recruitment as compared to Ad. Null transduction. Hyperoxia was associated with diffuse apoptosis that was inhibited only in patchy areas of endothelial proliferation under VEGF transduction.Hyperoxia-induced alveolar inflammation was similar with Ad.Null and Ad.VEGF. Under normoxia, the high dose of VEGF transduction induced diffuse alveolar inflammation whereas the low dose did not suggesting a pro-inflammatory effect of VEGF that may have participated to increased survival under hyperoxia. Conclusions:We demonstrate that lung VEGF-A transduction despite inhibition of the loss of capillary bed has a marginal effect of on animal survival during hyperoxia-induced injury..</div
Incursions upon agricultural land within metropolitan peripheries: Deadlocks and geo-legal trajectories of regularization in Paris and Mexico-city
No full textInternational audienceWithin metropolitan peripheries, irrespective of the national or regional contexts, the clash between rural and urban areas is at the center of metropolitan production. This clash is a twofold movement with urban sprawl, on the one hand, and major environmental injunctions, on the other. By looking at the two contexts of Paris and Mexico City, our research objective is to comprehend peripheries as places magnifying competing land dynamics, leading to scenarios of crises as well as social, political and legal innovations. The methodology is based on the analysis of field observations and surveys, public databases and official documents, using a social geographical approach. The article analyzes how stakeholders within the land system control peripheral land, focusing on public authorities, property market actors, and developers. The goal is to show the limitations of this control and reveal how and why residents and citizen groups build arrangements and regularizations. At the end, this article aims to contribute to the debates on the land rules deadlocks in the urban-rural interface. From different deadlocks observed in each context, the comparison underlines converging geo-legal trajectories of land regulation
A Cauchy-Piola framework for micro-based micromorphic continua
No full textInternational audienceMany results on micromorphic media can be found in the literature, where the equations of motion and the energetic foundations of the Eringen micromorphic continuum have been well established. The present paper has been devoted to the continuum modeling of a finite number of interacting, separated continua (microdomains) at the microscale, in which the strain energy has been formulated through a generalization of the Cauchy-Green deformation tensor, resulting in a degenerate metric at the considered scale, and a (6 × 6) Green-Lagrange strain tensor. The equilibrium equations have been obtained by systematically applying the method of virtual power. For one of the first time, boundary-layer conditions appear in micromorphic mechanics. The paper concludes with a discussion on the number of constitutive parameters, shown to coincide, in number, with those of classical (Cauchy) elasticity, together with the recovery of micropolar continua as a special case and wide spectrum of applications of the proposed framework. Further details concerning the algebraic expressions of the tensors involved are provided in the Appendices
Natural Disasters and Economic Resilience in Caribbean
No full textInternational audienceNatural disasters are major threats to economic and human development, often leading to substantial disruptions in growth and welfare, particularly in developing countries. Focusing on twelve small island economies in the Caribbean, this paper examines the effects of natural disasters between 1992 and 2019 on key indicators of economic performance and development. Using a disaggregated empirical approach and satellite-based night-time light data, we estimate fixed-effects OLS models including a full set of country, region, and year effects, as well as country- and region-specific linear trends. The results indicate that natural disasters cause a significant contraction in local economic activity and in the rate of economic development. Complementary estimates from a Panel Vector Autoregression model show that these negative effects persist for up to four years after disaster events. Moreover, countries with higher income per capita, stronger institutions, greater political stability, and a higher degree of trade openness are found to be more resilient to disaster shocks. The study concludes by identifying structural factors that can strengthen macroeconomic resilience and by providing policy-relevant insights for mitigating the economic consequences of natural disasters
Des « miasmes » et « germes » du XIXᵉ siècle au Covid-19, ces controverses historiques sur le mode de transmission des épidémies
No full textUne mise en perspective historique éclaire la position initiale prise par l’Organisation mondiale de la santé lors du déclenchement de la pandémie de Covid-19. L’agence de l’ONU avait d’abord minoré la transmission par voie aérienne, mode de propagation majoritaire du SARS-CoV-2.Une mise en perspective historique éclaire la position initiale prise par l’Organisation mondiale de la santé lors du déclenchement de la pandémie de Covid-19. L’agence de l’ONU avait d’abord minoré la transmission par voie aérienne, mode de propagation majoritaire du SARS-CoV-2