Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Chlordecone is a persistent organochlorine pesticide that was used in the French West Indies until the early 1990s for banana weevil borer control. Human exposure to this chemical in this area still occurs nowadays due to consumption of contaminated food. Although adverse effects on neurodevelopment, including tremors and memory deficits, have been documented in experimental studies conducted with rodents exposed during the gestational and neonatal periods, no study has been conducted yet to determine if chlordecone alters child development. This study examines the relation of gestational and postnatal exposure to chlordecone to infant development at 18 months of age in a birth-cohort of Guadeloupean children. In a prospective longitudinal study conducted in Guadeloupe (Timoun mother-child cohort study), exposure to chlordecone was measured at birth from an umbilical cord blood sample (n=141) and from a breast milk sample collected at 3 months postpartum (n=75). Toddlers were assessed using an adapted version of the Ages and Stages Questionnaire. Higher chlordecone concentrations in cord blood were associated with poorer fine motor scores. When analyses were conducted separately for boys and girls, this effect was only observed among boys. These results suggest that prenatal exposure to chlordecone is associated with specific impairments in fine motor function in boys, and add to the growing evidence that exposure to organochlorine pesticides early in life impairs child development.
ISSN: 0161-813X

hal-00875907
https://hal.archives-ouvertes.fr/hal-00875907
PUBMED : 23376090
DOI : 10.1016/j.neuro.2013.01.007

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
BACKGROUND: The insecticide chlordecone was extensively used in the French West Indies to control banana root borer. Its persistence in soils has led to the widespread pollution of the environment, and human beings are still exposed to this chemical. Chlordecone has been shown to impair neurological and behavioural functions in rodents when exposed gestationally or neonatally. OBJECTIVES: The aim of the study was to evaluate the impact of prenatal and postnatal exposure to chlordecone on the cognitive, visual, and motor development of 7-month-old infants from Guadeloupe. METHODS: Infants were tested at 7 months (n=153). Visual recognition memory and processing speed were assessed with the Fagan Tests of Infant Intelligence (FTII), visual acuity with the Teller Acuity Card, and fine motor development with the Brunet-Lezine. Samples of cord blood and breast milk at 3 months (n=88) were analyzed for chlordecone concentrations. Postnatal exposure was determined through breast feeding and frequency of contaminated food consumption by the infants. RESULTS: Cord chlordecone concentrations in tertiles were associated with reduced novelty preference on the FTII in the highly exposed group (β=-0.19, p=0.02). Postnatal exposure through contaminated food consumption was marginally related to reduced novelty preference (β=-0.14, p=0.07), and longer processing speed (β=0.16, p=0.07). Detectable levels of chlordecone in cord blood were associated with higher risk of obtaining low scores on the fine motor development scale (OR=1.25, p<0.01). CONCLUSION: These results suggest that pre- and postnatal low chronic exposure to chlordecone is associated with negative effects on cognitive and motor development during infancy.
ISSN: 0013-9351

hal-00875939
https://hal.archives-ouvertes.fr/hal-00875939
DOI : 10.1016/j.envres.2012.07.006
PUBMED : 22910562

Éditeur(s) : HAL CCSD Editions Paralia CFL
Résumé : Des techniques d'optimisation de formes sont utilisées dans des problèmes du Génie Côtier pour la protection des plages. En collaboration avec le bureau d'étude Bas-Rhône Languedoc ingénierie, un projet d'aménagement concret de la plage du Lido de Sète, utilisant des ouvrages immergés en géotextile, a été étudié. Des solutions optimales, visant à réduire la mise en suspension des sédiments, pour les structures de défenses ont été obtenues à partir d'un modèle hydrodynamique de propagation de houle. Une étude complémentaire à partir d'un modèle de circulation et des travaux expérimentaux en canal à houle permettent ensuite de valider les résultats optimaux numériques obtenus. Shape optimization techniques, focusing on coastal structures design, are used to solve coastal engineering problem. In collaboration with the Bas-Rhône Languedoc engineering Company, a actual development plan concerning the beach of the Lido of Sète has been studied. Optimal solutions, aimed at reducing sediments suspended, for defense structures have been obtained with a hydrodynamic water wave model. An additional study using a circulation model and experimental works in flume tend to validate optimal numerical results.
ISSN: 1760-8716

hal-00854031
https://hal.archives-ouvertes.fr/hal-00854031
DOI : 10.5150/jngcgc.2008.025-I

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Intrinsic tribological properties of lamellar compounds are usually attributed to the presence of van der Waals gaps in their structure through which interlayer interactions are weak. The controlled variation of the distances and interactions between graphene layers by intercalation of electrophilic species in graphite is used in order to explore more deeply the friction reduction properties of low-dimensional compounds. Three graphite intercalation compounds with antimony pentachloride, iron trichloride and aluminium trichloride are studied. Their tribological properties are correlated to their structural parameters, and the interlayer interactions are deduced from ab initio bands structure calculations.
ISSN: 1023-8883

hal-00767639
https://hal.archives-ouvertes.fr/hal-00767639
https://hal.archives-ouvertes.fr/hal-00767639/document
https://hal.archives-ouvertes.fr/hal-00767639/file/Delbe_6330.pdf
DOI : 10.1007/s11249-012-9981-0

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Perinatal exposure to endocrine-disrupting chemicals may affect thyroid hormones homeostasis and impair brain development. Chlordecone, an organochlorine insecticide widely used in the French West Indies has known estrogenic and progestin properties, but no data is available, human or animal, on its action on thyroid hormone system. Our aim was to evaluate the impact of perinatal exposure to chlordecone on the thyroid hormone system of a sample of infants from the Timoun mother-child cohort in Guadeloupe and their further neurodevelopment. Chlordecone was measured in cord blood and breast milk samples. Thyroid stimulating hormone (TSH), free tri-iodothyronine (FT3), free thyroxine (FT4) were determined in child blood at 3 months (n=111). Toddlers were further assessed at 18 months using an adapted version of the Ages and Stages Questionnaire (ASQ). Cord chlordecone was associated with an increase in TSH in boys, whereas postnatal exposure was associated with a decrease in FT3 overall, and in FT4 among girls. Higher TSH level at 3 months was positively associated with the ASQ score of fine motor development at 18 months among boys, but TSH did not modify the association between prenatal chlordecone exposure and poorer ASQ fine motor score. Perinatal exposure to chlordecone may affect TSH and thyroid hormone levels at 3 months, differently according to the sex of the infant. This disruption however did not appear to intervene in the pathway between prenatal chlordecone exposure and fine motor child development.
ISSN: 0013-9351

hal-01134317
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01134317
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01134317/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01134317/file/Perinatal%20exposure%20to%20chlordecone_accepted.pdf
PUBMED : 25747818

Éditeur(s) : HAL CCSD
Résumé : International audience
In the analysis of coastal hazards, the features of extreme waves are determining information to question the impact of storms to the coast. The spatial behaviour of extreme waves is even more valuable especially since it is sparsely provided. Regarding recent applications in other contexts, a kind of statistical models called max-stable processes is relevant for modelling spatial extreme events. Max-stable processes are extensions of the well-known Generalised Extreme Value (GEV) distribution. Unlike univariate approaches, max-stable processes consider spatial dependence of a phenomenon. Such a modelling also overtakes a standard multivariate approach by providing information continuously over the area studied, even where no observation is available. Relying on such a stochastic modelling, the aim of this study is to discuss the extreme waves hazards in the Gulf of Lions, focusing on their spatial behaviour.
34th Conference on Coastal Engineering
Seoul, South Korea

lirmm-01382568
https://hal-lirmm.ccsd.cnrs.fr/lirmm-01382568
https://hal-lirmm.ccsd.cnrs.fr/lirmm-01382568/document
https://hal-lirmm.ccsd.cnrs.fr/lirmm-01382568/file/7553-31212-1-PB.pdf
DOI : 10.9753/icce.v34.management.17

Éditeur(s) : HAL CCSD
Résumé : International audience
It is classically admitted that the goodfriction properties of lamellar compounds are strongly related to their anisotropic structure and especially to the existence of weak interlayer interactions through the van der Waals gap separating the basal layers. As it is also known, the presence of the van der Waals gap in the structure of lamellar compounds will allow lot of chemical species to be intercalated in the structure leading both to the expansion of structure parameters and inter layer interactions modifications. The present work is concerned with the experimental and theoretical study of friction propertiesof Graphite Intercalated Compounds (GICs) in order to better understand thetribologiclamellar compounds. In order to modulate the interlayer interactions, two types of intercalated species were used, electrophylic species (AlCl3, FeCl3, SbCl5) and nucleophilic species (Li, K, Rb).
40th Leeds-Lyon Symposium on Tribology & Tribochemistry Forum 2013
Lyon, France

Droits : info:eu-repo/semantics/OpenAccess
hal-00926509
https://hal.archives-ouvertes.fr/hal-00926509
https://hal.archives-ouvertes.fr/hal-00926509/document
https://hal.archives-ouvertes.fr/hal-00926509/file/Delbe_9781.pdf
OATAO : 9781