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International audience; Ion processes are a key driver of chemistry in a wide variety of natural dilute environments such as the ionosphere of Earth, the atmosphere of solar system planets, and satellites and interstellar clouds. They also play a role in low-temperature plasmas that are commonly encountered in industrial settings. Uniform supersonic flows have proved to be pivotal in gaining insights into the kinetics of ionic processes. In more than three decades, a variety of ion-molecule reactions has been investigated with the CRESU (French acronym standing for Kinetics of Reactions with Uniform Supersonic Flows) method. They include bimolecular and termolecular reactions and often depart from predictions made by simple empirical models. Neglected in the 90s for the benefit of the study of less predictable radical-neutral reactions, the exploration of ion-molecule reactive collisions has seen a recent revival. It has been in particular stimulated by the discovery of molecular anions in astrophysical environments for which the formation and destruction processes remain elusive, mostly due to the lack of kinetic and branching ratio data. Despite the growing sophistication of competing methods which include crossed beams or cooled ion traps, uniform supersonic flows continue to be a method of choice, one of the rare techniques to provide rate coefficients obtained under well-controlled thermalized conditions over a wide range of low temperatures. Uniform supersonic flows turn out to be well suited for heavy neutral co-reactants. Some challenges remain and call for new directions of action. In a last section, the most promising routes and the limits of the method are outlined. The extension of the method to the study of dissociative recombination sounds perilous, and state-selective chemistry with ions could only marginally benefit from the CRESU. From a technical point of view, the implementation of isomer-specific detection schemes could, however, greatly expand the scope of ion-molecule reaction studies. In tight connection with planetary sciences, ion-induced nucleation appears to be a topic within reach today using the CRESU technique. Further development of the approach will contribute to validate approximate treatments and push further the knowledge of ion-molecule reactions at low temperatures. © 2022 by World Scientific Publishing Europe Ltd.

International audience; Background: We examined how the relationship between education and latelife cognitive impairment (defined as a Mini Mental State Examination score below 24) is influenced by age, sex, ethnicity, and Apolipoprotein E epsilon 4 (APOE*4).Methods: Participants were 30,785 dementia-free individuals aged 55-103 years, from 18 longitudinal cohort studies, with an average follow-up ranging between 2 and 10 years. Pooled hazard ratios were obtained from multilevel parametric survival analyses predicting cognitive impairment (CI) from education and its interactions with baseline age, sex, APOE*4 and ethnicity. In separate models, education was treated as continuous (years) and categorical, with participants assigned to one of four education completion levels: Incomplete Elementary; Elementary; Middle; and High School.Results: Compared to Elementary, Middle (HR = 0.645, P = 0.004) and High School (HR = 0.472, P < 0.001) education were related to reduced CI risk. The decreased risk of CI associated with Middle education weakened with older baseline age (HR = 1.029, P = 0.056) and was stronger in women than men (HR = 1.309, P = 0.001). The association between High School and lowered CI risk, however, was not moderated by sex or baseline age, but was stronger in Asians than Whites (HR = 1.047, P = 0.044), and significant among Asian (HR = 0.34, P < 0.001) and Black (HR = 0.382, P = 0.016), but not White, APOE*4 carriers.Conclusion: High School completion may reduce risk of CI associated with advancing age and APOE*4. The observed ethnoregional differences in this effect are potentially due to variations in social, economic, and political outcomes associated with educational attainment, in combination with neurobiological and genetic differences, and warrant further study.

We aimed to examine the relationship between Apolipoprotein E ε4 (APOE*4) carriage on cognitive decline, and whether these associations were moderated by sex, baseline age, ethnicity, and vascular risk factors. Participants were 19,225 individuals aged 54–103 years from 15 longitudinal cohort studies with a mean follow-up duration ranging between 1.2 and 10.7 years. Two-step individual participant data meta-analysis was used to pool results of study-wise analyses predicting memory and general cognitive decline from carriage of one or two APOE*4 alleles, and moderation of these associations by age, sex, vascular risk factors, and ethnicity. Separate pooled estimates were calculated in both men and women who were younger (ie, 62 years) and older (ie, 80 years) at baseline. Results showed that APOE*4 carriage was related to faster general cognitive decline in women, and faster memory decline in men. A stronger dose-dependent effect was observed in older men, with faster general cognitive and memory decline in those carrying two versus one APOE*4 allele. Vascular risk factors were related to an increased effect of APOE*4 on memory decline in younger women, but a weaker effect of APOE*4 on general cognitive decline in older men. The relationship between APOE*4 carriage and memory decline was larger in older-aged Asians than Whites. In sum, APOE*4 is related to cognitive decline in men and women, although these effects are enhanced by age and carriage of two APOE*4 alleles in men, a higher numbers of vascular risk factors during the early stages of late adulthood in women, and Asian ethnicity. © The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved.

Background: We examined how the relationship between education and latelife cognitive impairment (defined as a Mini Mental State Examination score below 24) is influenced by age, sex, ethnicity, and Apolipoprotein E epsilon 4 (APOE*4). Methods: Participants were 30,785 dementia-free individuals aged 55–103 years, from 18 longitudinal cohort studies, with an average follow-up ranging between 2 and 10 years. Pooled hazard ratios were obtained from multilevel parametric survival analyses predicting cognitive impairment (CI) from education and its interactions with baseline age, sex, APOE*4 and ethnicity. In separate models, education was treated as continuous (years) and categorical, with participants assigned to one of four education completion levels: Incomplete Elementary; Elementary; Middle; and High School. Results: Compared to Elementary, Middle (HR = 0.645, P = 0.004) and High School (HR = 0.472, P < 0.001) education were related to reduced CI risk. The decreased risk of CI associated with Middle education weakened with older baseline age (HR = 1.029, P = 0.056) and was stronger in women than men (HR = 1.309, P = 0.001). The association between High School and lowered CI risk, however, was not moderated by sex or baseline age, but was stronger in Asians than Whites (HR = 1.047, P = 0.044), and significant among Asian (HR = 0.34, P < 0.001) and Black (HR = 0.382, P = 0.016), but not White, APOE*4 carriers. Conclusion: High School completion may reduce risk of CI associated with advancing age and APOE*4. The observed ethnoregional differences in this effect are potentially due to variations in social, economic, and political outcomes associated with educational attainment, in combination with neurobiological and genetic differences, and warrant further study. © 2020 Elsevier B.V.

International audience; In Québec, the integration between different steps in the reforestation process, from seeds to outplanting, is unparalleled. The Direction de la recherche forestière (DRF the Research Directorate) of the ministère des Ressources naturelles et de la Faune (MRNF Ministry of Natural Resources and Wildlife) has a multidisciplinary research group which includes expertise in forest genetics, seed orchard management, seed technology, mass cutting propagation, somatic embryogenesis, seedling production, environmental monitoring, planting techniques and forest plantation sylviculture. In close collaboration with other research agencies (universities, research centres), this group is responsible for acquiring, integrating and transferring research results related to seed and plant production to the 24 Québec forest nurseries (6 government and 18 private), the provincial seed centre and the cutting propagation and somatic embryogenesis centres. DRF projects must answer research and development needs and are subject to rigorous evaluations of both pertinence and scientific value by independent committees. The evaluation of these projects, as well as those submitted by other research institutions, is administered by an independent agency (Fonds québécois de la recherche sur la nature et les technologies). The present report outlines the salient facts and results of the principal studies related to seed and plant production: seed germination and sowing factors, assessment of water activity, production of hybrid larch seed, genetics of seedling production, characterization and early selection of hybrid poplar clones, vegetative propagation by rooted stem cuttings and somatic embryogenesis (ES), as well as controlled crosses of plants produced by ES.; Au Québec, l'intégration des différentes étapes dans le processus de reboisement, des graines aux plants, est sans égal. La direction de la recherche forestière (DRF) du ministère des ressources naturelles et de la Faune (MRNF) a un groupe de recherche multidisciplinaire qui inclut l'expertise dans la génétique forestière, la gestion de vergers à graines, la technologie de la graine, la propagation de masse par bouturage, l'embryogenèse somatique, la production de plants, le contrôle de l'environnement, les techniques de plantation et la sylviculture des reboisements. En collaboration étroite avec d'autres agences de recherches (universités, centres de recherches), ce groupe a la charge d'acquérir, d'intégrer et de transférer les résultats de la recherche liés à la production de semences et de plants aux 24 pépinières forestières du Québec (6 gouvernementales et 18 privées), au centre provincial de semences ainsi qu'aux centres de propagation par bouturage et par embryogenèse somatique. Les projets de DRF doivent répondre aux besoins de recherche et de développement et sont soumis à des évaluations rigoureuses de leur pertinence et de leur valeur scientifique par des comités indépendants. L'évaluation de ces projets, aussi bien que ceux soumis par d'autres établissements de recherches, est administrée par une agence indépendante (Fonds québécois de la recherche sur la nature et les technologies). Le présent rapport décrit les faits et les résultats marquants des principales études relatives à la production de semences et de plants : de la germination et les facteurs d'ensemencement, l'évaluation de l'activité de l'eau, la production de graines hybrides de mélèze, la structuration génétique lors de la production de plants, la caractérisation et la sélection précoce de clones de peupliers hybrides, la multiplication végétative par bouturage de tiges et l'embryogenèse somatique (es), comme les croisements contrôlés d'arbres issus de l'embryogenèse somatique.

We report a large genomic deletion of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, viz.. a deletion that is frequently observed in Central and Eastern Europe. The mutation, termed CFTRdele2.3(21 kb), deletes 21,080 bp spanning introns 1-3 of the CFTR gene. Transcript analyses have revealed that this deletion results in the loss of exons 2 and 3 in epithelial CFTR mRNA, thereby producing a premature termination signal within exon 4. In order to develop a simple polymerase chain reaction assay for this allele, we defined the end-points of the deletion at the DNA sequence level. We next screened for this mutation in a representative set of European and European-derived populations. Some 197 CF patients, including seven homozygotes, bearing this mutation have been identified during the course of our study. Clinical evaluation of CFTRdele2.3(21 kb) homozygotes and a comparison of compound heterozygotes for Delta F508/CFTRdele2,3(21 kb) with pairwise-matched Delta F508 homozygotes indicate that this deletion represents a severe mutation associated with pancreatic insufficiency and early age at diagnosis. Current data show that the mutation is particularly common in Czech (6.4% of all CF chromosomes), Russian (5.2%), Belorussian (3.3%). Austrian (2.6%), German (1.5%), Polish (1.5%), Slovenian (1.5%), Ukrainian (1.2%), and Slovak patients (1.1%). It has also been found in Lithuania, Latvia, Macedonia and Greece and has sporadically been observed in Canada, USA, France, Spain, Turkey, and UK, but not in CF patients from Bulgaria, Croatia, Romania or Serbia. Haplotype analysis has identified the same extragenic CF-haplotype: XV-2c/KM. 19 “A” and the same infrequent intragenic microsatellite haplotype 16-33-13 (IVS8CA-IVS17bTA-IVSI7bCA) in all examined CFTRdele2,3(21 kb) chromosomes, suggesting a common origin for this deletion. We conclude that the 21-kb deletion is a frequent and severe CF mutation in populations of Eastern- and Western-Slavic descent.