Development of Cross-Linked Polystyrene-Supported Chiral Amines Featuring a Fluorinated Linker for Gel-Phase 19 F NMR Spectrometry Monitoring of Reactions

International audienc

Les concepts de l’usine du futur appliqués aux chantiers d’assainissement et de démantèlement

Le CEA en est convaincu, l’ensemble des concepts et méthodes de l’usine du futur peuvent s’appliquer aux chantiers d’assainissement et de démantèlement nucléaires, quelle que soit leur nature. À Marcoule, les équipes de l’organisme de recherche s’inspirent de l’industrie manufacturière pour modéliser toutes les étapes de la reprise au conditionnement des déchets radioactifs. En utilisant les technologies de l’industrie du futur – cobotique, réalité virtuelle, numérique pour l’analyse des données et l’interconnexion des systèmes, etc. – l’instrumentation est appelée à évoluer permettant de rendre les procédés plus sûrs et plus performants

Intégration du démantèlement lors de la conception des installations nucléaires

Le retour d’expérience acquis en assainissement-démantèlement des diverses installations nucléaires de typologies variées (usines du cycle, réacteurs, installations de R&D, accélérateurs…) a montré que certaines dispositions prises dès la conception (possibilité de démonter à distance, suppression de certaines impuretés susceptibles d’activation, protection des zones pouvant être contaminées, etc.) pouvaient simplifier notablement les opérations de démantèlement. Cette connaissance a été capitalisée récemment par l’AIEA et l’OCDE qui ont publié des recommandations correspondantes. Cet article résume ces recommandations et donne des exemples d’application dans certains projets en cours de conception en France

Chiral Discrimination in Host−Guest Supramolecular Complexes. Understanding Enantioselectivity and Solid Solution Behaviors by Using Spectroscopic Methods and Chemical Sensors

International audienc

Biogeography of ocean acidification: Differential field performance of transplanted mussels to upwelling-driven variation in carbonate chemistry.

Ocean acidification (OA) represents a serious challenge to marine ecosystems. Laboratory studies addressing OA indicate broadly negative effects for marine organisms, particularly those relying on calcification processes. Growing evidence also suggests OA combined with other environmental stressors may be even more deleterious. Scaling these laboratory studies to ecological performance in the field, where environmental heterogeneity may mediate responses, is a critical next step toward understanding OA impacts on natural communities. We leveraged an upwelling-driven pH mosaic along the California Current System to deconstruct the relative influences of pH, ocean temperature, and food availability on seasonal growth, condition and shell thickness of the ecologically dominant intertidal mussel Mytilus californianus. In 2011 and 2012, ecological performance of adult mussels from local and commonly sourced populations was measured at 8 rocky intertidal sites between central Oregon and southern California. Sites coincided with a large-scale network of intertidal pH sensors, allowing comparisons among pH and other environmental stressors. Adult California mussel growth and size varied latitudinally among sites and inter-annually, and mean shell thickness index and shell weight growth were reduced with low pH. Surprisingly, shell length growth and the ratio of tissue to shell weight were enhanced, not diminished as expected, by low pH. In contrast, and as expected, shell weight growth and shell thickness were both diminished by low pH, consistent with the idea that OA exposure can compromise shell-dependent defenses against predators or wave forces. We also found that adult mussel shell weight growth and relative tissue mass were negatively associated with increased pH variability. Including local pH conditions with previously documented influences of ocean temperature, food availability, aerial exposure, and origin site enhanced the explanatory power of models describing observed performance differences. Responses of local mussel populations differed from those of a common source population suggesting mussel performance partially depended on genetic or persistent phenotypic differences. In light of prior research showing deleterious effects of low pH on larval mussels, our results suggest a life history transition leading to greater resilience in at least some performance metrics to ocean acidification by adult California mussels. Our data also demonstrate "hot" (more extreme) and "cold" (less extreme) spots in both mussel responses and environmental conditions, a pattern that may enable mitigation approaches in response to future changes in climate

Biogeography of ocean acidification: Differential field performance of transplanted mussels to upwelling-driven variation in carbonate chemistry.

Ocean acidification (OA) represents a serious challenge to marine ecosystems. Laboratory studies addressing OA indicate broadly negative effects for marine organisms, particularly those relying on calcification processes. Growing evidence also suggests OA combined with other environmental stressors may be even more deleterious. Scaling these laboratory studies to ecological performance in the field, where environmental heterogeneity may mediate responses, is a critical next step toward understanding OA impacts on natural communities. We leveraged an upwelling-driven pH mosaic along the California Current System to deconstruct the relative influences of pH, ocean temperature, and food availability on seasonal growth, condition and shell thickness of the ecologically dominant intertidal mussel Mytilus californianus. In 2011 and 2012, ecological performance of adult mussels from local and commonly sourced populations was measured at 8 rocky intertidal sites between central Oregon and southern California. Sites coincided with a large-scale network of intertidal pH sensors, allowing comparisons among pH and other environmental stressors. Adult California mussel growth and size varied latitudinally among sites and inter-annually, and mean shell thickness index and shell weight growth were reduced with low pH. Surprisingly, shell length growth and the ratio of tissue to shell weight were enhanced, not diminished as expected, by low pH. In contrast, and as expected, shell weight growth and shell thickness were both diminished by low pH, consistent with the idea that OA exposure can compromise shell-dependent defenses against predators or wave forces. We also found that adult mussel shell weight growth and relative tissue mass were negatively associated with increased pH variability. Including local pH conditions with previously documented influences of ocean temperature, food availability, aerial exposure, and origin site enhanced the explanatory power of models describing observed performance differences. Responses of local mussel populations differed from those of a common source population suggesting mussel performance partially depended on genetic or persistent phenotypic differences. In light of prior research showing deleterious effects of low pH on larval mussels, our results suggest a life history transition leading to greater resilience in at least some performance metrics to ocean acidification by adult California mussels. Our data also demonstrate "hot" (more extreme) and "cold" (less extreme) spots in both mussel responses and environmental conditions, a pattern that may enable mitigation approaches in response to future changes in climate

Groundfish data for analysis from Signatures of the collapse and incipient recovery of an overexploited marine ecosystem

Zipped file of data files required for analyse

Supplementary Materials from Signatures of the collapse and incipient recovery of an overexploited marine ecosystem

Two supplemental tables and six supplemental figures for the main tex