Éditeur(s) : HAL CCSD Wiley-VCH Verlag
Résumé : International audience
Deciphering the assembly history of the Milky Way is a formidable task, which becomes possible only if one can produce high-resolution chrono-chemo-kinematical maps of the Galaxy. Data from large-scale astrometric and spectroscopic surveys will soon provide us with a well-defined view of the current chemo-kinematical structure of the Milky Way, but will only enable a blurred view on the temporal sequence that led to the present-day Galaxy. As demonstrated by the (ongoing) exploitation of data from the pioneering photometric missions CoRoT, Kepler, and K2, asteroseismology provides the way forward: solar-like oscillating giants are excellent evolutionary clocks thanks to the availability of seismic constraints on their mass and to the tight age-initial-mass relation they adhere to. In this paper we identify five key outstanding questions relating to the formation and evolution of the Milky Way that will need precise and accurate ages for large samples of stars to be addressed, and we identify the requirements in terms of number of targets and the precision on the stellar properties that are needed to tackle such questions. By quantifying the asteroseismic yields expected from PLATO for red-giant stars, we demonstrate that these requirements are within the capabilities of the current instrument design, provided that observations are sufficiently long to identify the evolutionary state and allow robust and precise determination of acoustic-mode frequencies. This will allow us to harvest data of sufficient quality to reach a 10% precision in age. This is a fundamental pre-requisite to then reach the more ambitious goal of a similar level of accuracy, which will only be possible if we have to hand a careful appraisal of systematic uncertainties on age deriving from our limited understanding of stellar physics, a goal which conveniently falls within the main aims of PLATO's core science.
ISSN: 0004-6337

hal-01541393
https://hal.archives-ouvertes.fr/hal-01541393
ARXIV : 1706.3778
BIBCODE : 2017AN....338..644M
DOI : 10.1002/asna.201713385

Éditeur(s) : HAL CCSD
Résumé : International audience
Cumulative human impacts have led to the degradation of marine ecosystems and thedecline of biodiversity in the European and contiguous seas. Effective conservationmeasures are urgently needed to reverse these trends. Conservation must entail societalchoices, underpinned by human values and worldviews that differ between the countriesbordering these seas. Social, economic and political heterogeneity adds to the challenge ofbalancing conservation with sustainable use of the seas. Comprehensive macro-regionalcoordination is needed to ensure effective conservation of marine ecosystems andbiodiversity of this region. Under the European Union Horizon 2020 framework programme,the MarCons COST action aims to promote collaborative research to support marinemanagement, conservation planning and policy development. This will be achieved bydeveloping novel methods and tools to close knowledge gaps and advance marineconservation science. This action will provide support for the development of macro-regional and national policies through six key actions: to develop tools to analysecumulative human impacts; to identify critical scientific and technical gaps in conservationefforts; to improve the resilience of the marine environment to global change and biologicalinvasions; to develop frameworks for integrated conservation planning across terrestrial,freshwater, and marine environments; to coordinate marine conservation policy acrossnational boundaries; and to identify effective governance approaches for marine protectedarea management. Achieving the objectives of these actions will facilitate the integration ofmarine conservation policy into macro-regional maritime spatial planning agendas for theEuropean and contiguous seas, thereby offsetting the loss of biodiversity and ecosystemservices in this region.
Research Ideas and Outcomes

hal-01474085
https://hal-univ-perp.archives-ouvertes.fr/hal-01474085
https://hal-univ-perp.archives-ouvertes.fr/hal-01474085/document
https://hal-univ-perp.archives-ouvertes.fr/hal-01474085/file/RIO_article_11884.pdf
DOI : 10.3897/rio.3.e11884

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Rapid cold hardening (RCH) is a form of thermal acclimation that allows ectotherms to fine-tune their physiological state to match rapid changes in thermal environment. Despite progress in recent years, there is still a considerable uncertainty regarding the physiological basis of RCH in insects. Here we investigated the physiological response of adult Drosophila melanogaster to a gradual reduction of temperature from 25 to 0°C followed by 1h at 0°C. As expected, this RCH treatment promoted cold tolerance, and so we hypothesized that this change could be detected at the proteomic level. Using 2D-DIGE, we found that only a few proteins significantly changed in abundance, and of these, we identified a set of four proteins of particular interest. These were identified as two different variants of glycogen phosphorylase (GlyP) of which three spots were up-regulated and another was down regulated. In subsequent experiments, we quantified upstream events by measuring the GlyP mRNA amount, but we found no marked effect of RCH. We also examined downstream events by measuring GlyP activity and the level of free sugars. We found no effect of RCH on GlyP activity. On the other hand, screening of whole animal sugar contents revealed a small increase in glucose levels following RCH while trehalose content was unaltered. This study highlights a complex regulation of GlyP in relation to RCH where we found associations between the cold tolerance, the protein abundance and the metabolite concentrations but no changes in mRNA expression and enzyme activity. These data stress the necessity of combining the hypothesis-generating power of an 'Omics' approach with subsequent targeted validations across several levels of the biological organization. We discuss reasons why different biological linked levels do not necessarily change stoichiometrically.
ISSN: 0022-1910

hal-00991032
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00991032
DOI : 10.1016/j.jinsphys.2014.01.009
PUBMED : 24508557

Éditeur(s) : HAL CCSD
Résumé : International audience
Women who drink light-to-moderately during pregnancy have been observed to have lower risk of unfavourable pregnancy outcomes than abstainers. This has been suggested to be a result of bias. In a pooled sample, including 193 747 live-born singletons from nine European cohorts, we examined the associations between light-to-moderate drinking and preterm birth, birth weight, and small-for-gestational age in term born children (term SGA). To address potential sources of bias, we compared the associations from the total sample with a sub-sample restricted to first-time pregnant women who conceived within six months of trying, and examined whether the associations varied across calendar time. In the total sample, drinking up to around six drinks per week as compared to abstaining was associated with lower risk of preterm birth, whereas no significant associations were found for birth weight or term SGA. Drinking six or more drinks per week was associated with lower birth weight and higher risk of term SGA, but no increased risk of preterm birth. The analyses restricted to women without reproductive experience revealed similar results. Before 2000 approximately half of pregnant women drank alcohol. This decreased to 39% in 2000–2004, and 14% in 2005–2011. Before 2000, every additional drink was associated with reduced mean birth weight, whereas in 2005–2011, the mean birth weight increased with increasing intake. The period-specific associations between low-to-moderate drinking and birth weight, which also were observed for term SGA, are indicative of bias. It is impossible to distinguish if the bias is attributable to unmeasured confounding, which change over time or cohort heterogeneity. © 2017, Springer Science+Business Media B.V.
ISSN: 03932990

hal-01647159
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01647159
DOI : 10.1007/s10654-017-0323-2
PUBMED : 29027084

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Thermal acclimation drastically alters thermotolerance of ectotherms, but the mechanisms determining this plastic response are not fully understood. The present study investigates the proteomic response (2D-DIGE) of adult Drosophila melanogaster acclimated at 11, 25 or 31 C. As expected 11 C-acclimation improved cold tolerance and 31 C-acclimation improved heat tolerance. We hypothesized that the marked organismal responses to acclimation could be detected at the proteomic level assuming that changes in the abundance of specific proteins are linked to the physiological changes underlying the phenotypic response. The 31 C-acclimated flies displayed a particular divergent proteomic profile where molecular chaperones made up a large number of the proteins that were modulated during heat acclimation. Many other proteins showed significant modulation during acclimation including proteins involved in iron ion and cell redox homeostasis, carbohydrate and energy metabolism, chromatin remodeling and translation, and contractile machinery. Interestingly the changes in protein abundance were often unrelated to transcriptional activity of the genes coding for the proteins, except for the most strongly expressed proteins (e.g. Hsp70). The 11 C-acclimation evoked weak proteomic response despite the marked effect on the organismal phenotype. Thus the acquired cold tolerance observed here may involve regulatory process such as posttranslational regulation rather than de novo protein synthesis.
ISSN: 0965-1748

hal-00826939
https://hal.archives-ouvertes.fr/hal-00826939
DOI : 10.1016/j.ibmb.2013.01.006
PUBMED : 23416132

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Low-level exposure to polychlorinated biphenyl-153 (PCB-153) and dichlorodiphenyldichloroethylene (p-p'-DDE) can impair fetal growth; however, the exposure-response relationship and effect modifiers of such association are not well established. This study is an extension of an earlier European meta-analysis. Our aim was to explore exposure-response relationship between PCB-153 and p-p'-DDE and birth outcomes; to evaluate whether any no exposure-effect level and susceptible subgroups exist; and to assess the role of maternal gestational weight gain (GWG). We used a pooled dataset of 9377 mother-child pairs enrolled in 14 study populations from 11 European birth cohorts. General additive models were used to evaluate the shape of the relationships between organochlorine compounds and birth outcomes. We observed an inverse linear exposure-response relationship between prenatal exposure to PCB-153 and birth weight [decline of 194g (95% CI -314, -74) per 1μg/L increase in PCB-153]. We showed effects on birth weight over the entire exposure range, including at low levels. This reduction seems to be stronger among children of mothers who were non-Caucasian or had smoked during pregnancy. The most susceptible subgroup was girls whose mothers smoked during pregnancy. After adjusting for absolute GWG or estimated fat mass, a reduction in birth weight was still observed. This study suggests that the association between low-level exposure to PCB-153 and birth weight exists and follows an inverse linear exposure-response relationship with effects even at low levels, and that maternal smoking and ethnicity modify this association.
ISSN: 0160-4120

hal-01118572
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01118572
PUBMED : 25314142
DOI : 10.1016/j.envint.2014.09.013

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
ABSTRACT: Environmental exposures during pregnancy and early life may have adverse health effects. Single birth cohort studies often lack statistical power to tease out such effects reliably. To improve the use of existing data and to facilitate collaboration among these studies, an inventory of the environmental exposure and health data in these studies was made as part of the ENRIECO (Environmental Health Risks in European Birth Cohorts) project. The focus with regard to exposure was on outdoor air pollution, water contamination, allergens and biological organisms, metals, pesticides, smoking and second hand tobacco smoke (SHS), persistent organic pollutants (POPs), noise, radiation, and occupational exposures. The review lists methods and data on environmental exposures in 37 European birth cohort studies. Most data is currently available for smoking and SHS (N=37 cohorts), occupational exposures (N=33), outdoor air pollution, and allergens and microbial agents (N=27). Exposure modeling is increasingly used for long-term air pollution exposure assessment; biomonitoring is used for assessment of exposure to metals, POPs and other chemicals; and environmental monitoring for house dust mite exposure assessment. Collaborative analyses with data from several birth cohorts have already been performed successfully for outdoor air pollution, water contamination, allergens, biological contaminants, molds, POPs and SHS. Key success factors for collaborative analyses are common definitions of main exposure and health variables. Our review emphasizes that such common definitions need ideally be arrived at in the study design phase. However, careful comparison of methods used in existing studies also offers excellent opportunities for collaborative analyses. Investigators can use this review to evaluate the potential for future collaborative analyses with respect to data availability and methods used in the different cohorts and to identify potential partners for a specific research question.
ISSN: 1476-069X

inserm-00785248
http://www.hal.inserm.fr/inserm-00785248
http://www.hal.inserm.fr/inserm-00785248/document
http://www.hal.inserm.fr/inserm-00785248/file/1476-069X-12-8.pdf
DOI : 10.1186/1476-069X-12-8

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
There are emerging concerns about potential effects on child health and development of early-life exposure to substances such as brominated flame retardants (BFRs), perfluorinated compounds (PFCs), phthalates and phenols (including bisphenol A (BPA)); pregnancy and birth cohort studies are ideally designed to study such concerns prospectively. As part of the ENRIECO project, we evaluated existing human biomonitoring data for these substances in European birth cohorts and develop recommendations for more harmonized methods that will enable combination and comparison of cohort data in the future. The ENRIECO inventory shows that 20 European birth cohorts have measured or are measuring BFRs (N=10), PFCs (N=11), phthalates (N=16) or phenols (N=8). Generally, samples were collected prenatally or at birth and measurements involved few subjects in each cohort (a few hundred maximum). Biological matrices, timing, and analytical methods of the measurements varied between cohorts. Few cohorts have measured at multiple time points or in children. In European cohorts, levels of BFRs were very low and at least 10-fold lower than in US; levels of PFCs and phthalates have decreased over the last decade since the phasing out of certain of these compounds; concentrations of phenols are comparable to those in the US. Although there is little published data in the cohorts now, many measurements are ongoing and we recommend that cohorts start working towards combined and comparison studies. Specific recommendations for use of existing data include the development of conversion models for the different media used for measurement of persistent chemicals, and inter-laboratory comparisons and calibrations. Recommendations for further data collection include more evaluation of exposure to these chemicals in children; repeated measurements of non-persistent chemicals; validation and harmonisation of questionnaires; and the development of mechanisms for fast European birth cohort response for the detection and prioritisation of new chemicals of concern.
ISSN: 1438-4639

hal-01118579
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01118579
DOI : 10.1016/j.ijheh.2012.05.009
PUBMED : 22795704