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The risk factors associated with metabolic syndrome (Met-S) including hypertension, hyperglycemia, central obesity, and dyslipidemia are preventable, particularly at their early stage. There are limited data available on the association between Met-S and preventable risk factors in young adults. We randomly selected 2,010 Saudis aged 18–30 years, who applied to be recruited in military colleges. All the procedures followed the guidelines of International Diabetes Federation. The results showed that out of 2,010 subjects, 4088 were affected with Met-S. The commonest risk factors were high blood sugar (63.6%), high systolic and diastolic blood pressures (63.3 and 37.3%), and high body mass index (57.5%). The prevalence of prediabetes and diabetes were 55.2 and 8.4%, respectively. Obesity, diabetes, hypertension, and hypertriglyceridemia were significantly associated with Met-S. The frequency of smoking was significantly linked with the development of Met-S. The prevalence of Met-S was found to be significantly higher in individuals with sedentary lifestyle. In conclusion, the results of this study clearly indicate that military recruits, who represent healthy young adults, are also prone to Met-S. The findings of this study will help in designing preventive measures as well as public awareness programs for controlling the high prevalence of Met-S in young adults.

Gypsum (CaSO4·2H2O) provides an opportunity to obtain information from both the oxygen isotopic composition of the water and sulfate of its formation waters, where these components are commonly sourced from different reservoirs (e.g., meteoric vs. magmatic). Here, we present δ18O values for gypsum and parent spring waters fed by the Kawah Ijen crater lake in East Java, Indonesia, and from these natural samples derive gypsum-fluid oxygen isotope fractionation factors for water and sulfate group ions of 1.0027 ± 0.0003‰ and 0.999 ± 0.001‰, respectively. Applying these fractionation factors to a growth-zoned gypsum stalactite that records formation waters from 1980 to 2008 during a period of passive degassing, and gypsum cement extracted from the 1817 eruption tephra fall deposit, shows that these fluids were in water-sulfate oxygen isotopic equilibrium. However, the 1817 fluid was >5‰ lighter. This indicates that the 1817 pre-eruption lake was markedly different, and had either persisted for a much shorter duration or was more directly connected to the underlying magmatic-hydrothermal system. This exploratory study highlights the potential of gypsum to provide a historical record of both the δ18Owater and δ18Osulfate of its parental waters, and provides insights into the processes acting on volcanic crater lakes or any other environment that precipitates gypsum.

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International audience; l’embouchure de l’oued Tamri, rive gauche, un paléorivage de faciès marin et fluvio-marin (unité U1) culmine aux environs de + 6m a.s.l. Une co-quille marine de Patella sp. prélevée dans cette unité U1 (faciès marin) a été datée 100,02 ± 1,662 ka et 101,188 ± 1,339 ka par la méthode U/Th (SIM 5.3). La dune surincombante (série Sx) a été datée par OSL 84 ± 4 ka (SIM 5.1). A Tighrine Imkssawne, à 200 m au Sud de l’embouchure, ce paléorivage est surmonté d’une séquence de dé-pôts dunaires et colluviaux de plus de 20 m d’épaisseur. Ces derniers renferment plusieurs paléosols rubéfiés interstratifiés et des encroûte-ments, témoins de périodes humides et de ruissel-lements, qui permettent de distinguer trois unités principales (unités U2, U3, U4) :(U2), unité d’accumulation interdunaire inférieure où dominent les faciès détritiques continentaux de colluvionnement/ruissellement. Elle renferme de nombreux Hélicidés et de rares témoins d’outillage lithique.(U3), unité d’accumulation éolienne moyenne, à séries dunaires encroûtées où la série (S5) a été datée par OSL 92 ± 6 ka (SIM 5.3 ou SIM 5.2), et où le paléosol rubéfié (S6) a fourni une industrie à proto-hachereaux.(U4), unité d’accumulation éolienne supérieure à séries friables, séparée de la précédente par une paléo-surface encroûtée (S6/S7) à industrie proba-blement épipaléolithique, et où des coquilles d’oeufs d’Autruche de la série (S8) sont datées par radiocarbone à plus de 30 ka. BPLes analyses géomorphologiques, sédimentolo-giques et pétrographiques aboutissent à un mo-dèle sédimentaire d’accumulation de pied de fa-laise morte qui permet de répondre aux contradic-tions apparentes entre la position de l’industrie lithique et des datations.

International audience; The Cueva del Angel (Lucena, Spain) is an open-air archaeological site with a sedimentary sequence remnant of a collapsed rock shelter which was part of a still active karst complex. The lithic assemblage consists essentially of abundant retouched tools including 46 identified handaxes along with non-modified flakes, and is associated with faunal remains dominated by Equus ferus and other large bovids and cervids. A large proportion of bones has undergone intense anthropic actions and been subjected to intense fire, thus evidencing sustained use of animal meat resources by humans. In order to better ascertain the chronological framework of the site, we dated several proxies. Various spe-leothem samples were processed by U-series using a coupled induced plasma mass spectrometer (ICPMS-MC). The resulting isotopic ratios are beyond the secular equilibrium and show that these samples do not appear to be in direct stratigraphic relation with the archaeological sequence. Nine Equus teeth were analyzed by the combined ESR/U-series method. These samples were taken from Unit I to Unit XVI representing at least 2.5 m of stratigraphic depth and approximately 90% of the infilling. Many of the dated samples are burnt given that more than 85% of the faunal remains exhibit traces of fire exposure. The bone retouchers, for which a comparative analysis with other sites has been published (Moigne et al., 2016), were probably produced during the Marine Isotope Stage (MIS 11-5) chronological interval corresponding to the later part of the Middle Pleistocene, inference that is in agreement with the palaeontological assemblage of the site. The radiometric results presented here are consistent and indicate a range from 350 to 183 ka, suggesting that a major part of the sedimentary infilling coinciding with the human occupation was contemporaneous with the MIS 9 to 7 time period.

The (234U/238) equilibrium state of borehole core samples from the deep, low-permeability limestone formations surrounding the target argilite layer of the Meuse/Haute-Marne experimental site of the French agency for nuclear waste management -ANDRA- (Agence nationale pour la gestion des déchets radioactifs) was examined to improve understanding of naturally occurring radionuclide behaviour in such geological settings. Highly precise, accurate MC-ICP-MS measurements of the (234U/238U) activity ratio show that limestone samples characterised by pressure dissolution structures (stylolites or dissolution seams) display systematic (234U/238U) disequilibria, while the pristine carbonate samples remain in the secular equilibrium state. The systematic feature is observed throughout the zones marked by pressure dissolution structures: (i) the material within the seams shows a deficit of 234U over 238U ((234U/238U) down to 0.80) and (ii) the surrounding carbonate matrix is characterised by an activity ratio greater than unity (up to 1.05). These results highlight a centimetric-scale uranium remobilisation in the limestone formations along these sub-horizontal seams. Although their nature and modalities are not fully understood, the driving processes responsible for these disequilibria were active during the last 1–2 Ma. Keywords: uranium isotopes, multiple-collector ICP-MS, waste management, remobilisation, migration

International audience

International audience; Ces dernières années, feu Amor Bkhairi était un chercheur dynamique et un animateur-clé de la coopération scientifique franco-tunisienne en géologie du Quaternaire et préhistoire. Sa coordination et sa participation à des projets de recherches impliquant les institutions françaises et tunisiennes a significativement contribué à préciser le cadre géochronologique et environnemental de la Tunisie centrale au Pléistocène et à l’Holocène. Pour ce colloque en hommage à notre collègue Amor Bkhairi, nous souhaitons présenter les objectifs scientifiques et les principaux résultats acquis dans les projets de recherche auxquels il a participé à nos côtés.Les projetsEnviMagO(Action Transversale du Muséum) et Carbo4 (DGRST-CNRS) étudient l’histoire des environnements de la Tunisie centrale au début du Pléistocène moyen dans des séquences paléo-lacustres du Haut-tell afin de définir le cadre chronologique des peuplements préhistoriques acheuléens. Sur le terrain, les prélèvements multi-paramètres (sédimentologie, palynologie, malacologie, microvertébrés) à haute-résolution temporelle permettent de caractériser les écosystèmes et les dynamiques hydro-sédimentaires des bassins lacustres et la composition de la végétation locale et régionale, ainsi que leurs réponses à la variabilité climatique il y a 700 000 ans. Dans ces séquences où alternent des dépôts détritiques et des formations carbonatées, les échantillons pour datations ESR et ESR-U/Th combinées donnent les jalons chronologiques indispensables pour replacer la description des milieux occupés par les Hommes préhistoriques de culture acheuléenne.Pour les périodes géologiques plus récentes de l’Holocène, le projet « Dynamique des écosystèmes à l’Holocène en Tunisie centrale » (PHC Utique) a pour objectif d’étudier les changements environnementaux et climatiques ainsi que l’évolution des paysages sur le versant méridional de la Dorsale Tunisienne au cours des 10 derniers millénaires. La séquence de la paléo-sebkha de Kasserine est un site clé de ce projet et des analyses sédimentologiques et palynologiques couplées à des datations 14C décrivent la dynamique des écosystèmes semi-aride au début de l’Holocène dans le contexte de la néolithisation en Tunisie Centrale.

International audience; Merging the late Quaternary Arctic paleoceanography into the Earth's global climate history remains challenging due to the lack of robust marine chronostratigraphies. Over ridges notably, low and variable sedimentation rates, scarce biogenic remains ensuing from low productivity and/or poor preservation, and oxygen isotope and paleomagnetic records differing from global stacks represent major impediments. However, as illustrate here based on consistent records from Mendeleev‐Alpha and Lomonosov Ridges, disequilibria between U‐series isotopes can provide benchmark ages. In such settings, fluxes of the particle‐reactive U‐daughter isotopes 230Th and 231Pa from the water column, are not unequivocally linked to sedimentation rates, but rather to sea‐ice rafting and brine production histories, thus to the development of sea‐ice factories over shelves during intervals of high relative sea level. The excesses in 230Th and 231Pa over fractions supported by their parent U‐isotopes, collapse down sedimentary sequences, due to radioactive decay, and provide radiometric benchmark ages of approximately 300 and 140 ka, respectively. These “extinction ages” point to mean sedimentation rates of ∼4.3 and ∼1.7 mm/ka, respectively, over the Lomonosov and Mendeleev Ridges, which are significantly lower than assumed in most recent studies, thus highlighting the need for revisiting current interpretations of Arctic lithostratigraphies in relation to the global‐scale late Quaternary climatostratigraphy.

International audience

Resumen del trabajo presentado en el World Congress of Malacology, celebrado en Ponta Delgada, Azores (Portugal), del 22 al 28 de julio de 2013

A comparative study of the climatic signals recorded in the Last Interglacial (~135–117 ka) coastal deposits from Sal Island (Cape Verde Archipelago), the Canary Islands and S-SE Iberian Peninsula is presented in this work, with particular attention paid to the fossil mollusc content. Palaeontological analyses are supported by previous geomorphological, stratigraphical and petrographical field data, including detailed mapping of marine and terrestrial deposits. Data are compared with previous works to reconstruct the coastal environments and climatic conditions during this time-period. Modern species distribution is compared with the fossil content in order to: 1) define those species that could be considered as warm-water proxies in the past; 2) describe the distribution of these species during the Last Interglacial in the Atlantic-Mediterranean linkage area; 3) interpret the oceanographic conditions that controlled the distribution and expansion of these molluscs during this time-period. A checklist of 52 warm-water species for the Canary and Mediterranean area is presented. In the Cape Verde archipelago and NW African coasts, more data related to the last and previous interglacial stages are necessary to confirm the palaeoclimatic and oceanographic interpretations, This work has been supported by funds of the following research projects: CGL2012/33430, CGL-2008-4000/BTE, CGL-2008-3998/BTE, Consolider- GRACCIE (CSD-2007-00067) IGCP 588, INQUA CMP Commission, GEOTOP Lab. Contrib., UCM R.G. 910198.

Trabajo presentado en el Macaronesian Paleoclimate Workshop, celebrado en Tenerife (España) , en octubre de 2012