Facteurs Explicatifs de la Fécondité des Femmes en union dans les Régions Septentrionales du Cameroun

A en croire les données des recensements, parmi les dix régions du Cameroun, celles septentrionales y représentent seules 34,4 % de sa population et ceci est dû au fait que la fécondité demeure très élevée dans ces régions. La présente étude s’est alors fixée comme objectif de chercher les déterminants de ce phénomène dans ces régions et de caractériser les femmes qui, toutes choses égales par ailleurs, y sont les plus concernées par le problème de forte fécondité. Pour atteindre ces objectifs, les données de l’Enquête Démographique et de Santé (EDS) réalisée au Cameroun en 2011 ont été utilisées. Leurs analyses ont été effectuées en recourant aux méthodes d’analyse de la variance, au niveau bivarié, et aux modèles de régression linéaire, au niveau multivarié explicatif. La valeur sociale de l’enfant étant élevée dans les milieux étudiés, il est ressorti des résultats de l’étude que la fécondité n’y varie pas significativement dans les ethnies autochtones et, contrairement à l’attente, elle est davantage élevée dans celles étrangères. Il en est aussi ressorti que la fécondité désirée est négativement associée aux religions chrétiennes, au degré élevé de modernité culturelle, au niveau de vie élevé, à l’exercice des activités dans le secteur moderne de l’économie et aux rapports égalitaires de genre, dans les régions où la relation entre chacun de ces facteurs et ce phénomène s’est avérée significative. En revanche, dans le cas de la fécondité effective, les effets inattendus de ces facteurs ont été davantage observés. Quant aux comportements de nuptialité, à savoir l’entrée tardive en union et les ruptures d’unions, ils ont tous été très négativement associés à la fécondité effective dans les milieux étudiés. En conclusion, la remise en question des valeurs sociales favorables à une forte fécondité est en cours dans ces milieux sous les effets des facteurs socioéconomiques mais elle devrait être renforcée par des actions de sensibilisation sur les conséquences néfastes d’une forte fécondité et accompagnée par celles d’amélioration de l’offre de Planification Familiale.   According to the census data, among the ten regions of Cameroon, the northern ones represent alone 34.4 % of its population and this is due to the fact that the level of fertility remains very high in these regions. Therefore, this study aims at highlighting the determinants of this phenomenon in these regions and characterizing the women who, all other things being equal, are the most concerned by the problem of high fertility. To achieve these objectives, data from the Cameroon 2011 Demographic and Health Survey (DHS) were analyzed, using the analysis of variance (ANOVA), at the bivariate level, and the linear regression models, at the explanatory multivariate level. As the child’s social value is high in the settings studied, the study results revealed that fertility does not significantly vary among native ethnic groups and, contrary to expectations, it is higher in foreign ones. They revealed also that the desired fertility is negatively associated with the Christian religions, the high degree of cultural modernity, the high standard of living, the exercise of activities in the modern sector of the economy, and the equal gender relations, in regions where the relationship between each of these factors and the desired fertility was significant. On the other hand, in the case of the effective fertility, the unintended effects of these factors were highlighted. As for marriage behaviors, namely the late entry into union and the union breakdown, they were all very negatively associated with effective fertility in the settings studied. In conclusion, the questioning of the social values favorable to high fertility is underway in the studied milieu under the influences of socioeconomic factors but it should be reinforced by the women’s sensitization on the harmful consequences of high fertility and accompanied by actions aimed at improving Family Planning offer

Thiron-Gardais – Parc de l’Abbaye

Le curage et la restauration du vivier situé dans le parc de l’église abbatiale de Thiron-Gardais ont été précédés par la réalisation de sondages archéologiques. Les sédiments observés, épais de 0,50 à plus d’1 m, semblent récents (céramique post-médiévale, fragments de verre, etc.), le bassin ayant dû être curé à plusieurs reprises. Aucun aménagement du fond du vivier n’avait été réalisé, l’argile alluviale ayant servi de fond imperméable. Mis à part le déversoir, les berges ne présentaient ..

Degradation of a benzene–toluene mixture by hydrocarbon-adapted bacterial communities

We examined the rate of degradation of a benzene–toluene mixture in aerobic microcosms prepared with samples of an aquifer that lies below a petrochemical plant (SIReN, UK). Five samples exposed to different concentrations of benzene (from 0.6 to 317 mg l−1) were used. Fast degradation (approx. 1–6 mg l−1 day−1) of both contaminants was observed in all groundwater samples and complete degradation was recorded by the seventh day except for one sample. We also identified the microbial community in each of the samples by culture-independent techniques. Two of the less impacted samples harbour the aerobic benzene degrader Pseudomonas fluorescens, while Acidovorax and Arthrobacter spp. were found in the most polluted sample and are consistent with the population observed in situ. Hydrogenophaga was found in the deepest sample while Rhodoferax spp. were recovered in an alkaline sample (pH 8.4) and may also be implicated in benzene degradation. Time series analysis shows that each of the samples has a different community but they remain stable over the degradation period. This study provides new information on a well not previously studied (no. 309s) and confirms that adapted communities have the ability to degrade hydrocarbon mixtures and could be used in further bioaugmentation approaches in contaminated sites

Ocean currents shape the microbiome of Arctic marine sediments

Prokaryote communities were investigated on the seasonally stratified Alaska Beaufort Shelf (ABS). Water and sediment directly underlying water with origin in the Arctic, Pacific or Atlantic oceans were analyzed by pyrosequencing and length heterogeneity-PCR in conjunction with physicochemical and geographic distance data to determine what features structure ABS microbiomes. Distinct bacterial communities were evident in all water masses. Alphaproteobacteria explained similarity in Arctic surface water and Pacific derived water. Deltaproteobacteria were abundant in Atlantic origin water and drove similarity among samples. Most archaeal sequences in water were related to unclassified marine Euryarchaeota. Sediment communities influenced by Pacific and Atlantic water were distinct from each other and pelagic communities. Firmicutes and Chloroflexi were abundant in sediment, although their distribution varied in Atlantic and Pacific influenced sites. Thermoprotei dominated archaea in Pacific influenced sediments and Methanomicrobia dominated in methane-containing Atlantic influenced sediments. Length heterogeneity-PCR data from this study were analyzed with data from methane-containing sediments in other regions. Pacific influenced ABS sediments clustered with Pacific sites from New Zealand and Chilean coastal margins. Atlantic influenced ABS sediments formed another distinct cluster. Density and salinity were significant structuring features on pelagic communities. Porosity co-varied with benthic community structure across sites and methane did not. This study indicates that the origin of water overlying sediments shapes benthic communities locally and globally and that hydrography exerts greater influence on microbial community structure than the availability of methane

Size resolved characterization of the polysaccharidic and proteinaceous components of sea spray aerosol

Dissolved organic polymers released by phytoplankton and bacteria abiologically self-assemble in surface ocean waters into nano-to micro-sized gels containing polysaccharides, proteins, lipids and other components. These gels concentrate in the sea surface microlayer (SML), where they can potentially contribute to sea spray aerosol (SSA). Sea spray is a major source of atmospheric aerosol mass over much of the earth’s surface, and knowledge of its properties (including the amount and nature of the organic content), size distributions and fluxes are fundamental for determining its role in atmospheric chemistry and climate. Using a cascade impactor, we collected size-fractionated aerosol particles from ambient air and from freshly generated Sea Sweep SSA in the western North Atlantic Ocean together with biological and chemical characterization of subsurface and SML waters. Spectrophotometric methods were applied to quantify the polysaccharide-containing transparent exopolymer (TEP) and protein-containing Coomassie stainable material (CSM) in these particles and waters. This study demonstrates that both TEP and CSM in surface ocean waters are aerosolized with sea spray with the greatest total TEP associated with particles <180 nm in diameter and >5 000 nm. The higher concentrations of TEP and CSM in particles >5 000 nm most likely reflects collection of microorganism cells and/or fragments. The greater concentration of CSM in larger size particles may also reflect greater stability of proteinaceous gels compared to polysaccharide-rich gels in surface waters and the SML. Both TEP and CSM were measured in the ambient marine air sample with concentrations of 2.1 ± 0.16 μg Xanthan Gum equivalents (XG eq.) m−3 and 14 ± 1.0 μg bovine serum albumin equivalents (BSA eq.) m−3. TEP in Sea Sweep SSA averaged 4.7 ± 3.1 μg XG eq. m−3 and CSM 8.6 ± 7.3 μg BSA eq. m−3. This work shows the transport of marine biogenic material across the air-sea interface through primary particle emission and the first demonstration of particle size discriminated TEP and CSM characterization of SSA and ambient aerosol under field conditions

Diversité des bactéries de la microcouche de surface de l'eau de mer (spécificité, adaptation et résistance aux radiations solaires)

La microcouche de surface est souvent enrichie en matières organiques d'origine naturelle et anthropique. La densité de microorganismes, qui constituent le bactérioneuston, est souvent très supérieure à celle trouvée dans la colonne d'eau. Des échantillons de microcouche de surface et d'eau sous-jacente ont été collectés pour isoler et analyser la diversité des bactéries cultivables. Le séquençage de l'ADNr 16S a révélé une grande diversité parmi les bactéries isolées de la microcouche. Parmi les souches isolées, certaines étaient tre s éloignées taxonomiquement d'espèces connues. Une majorité des souches a présenté une résistance importante face aux radiations solaires et ceci quelque soit leur localisation dans la colonne d'eau. L'ensemble des données obtenues nous a apporté des informations concernant la diversité et les stratégies d'adaptation du bactérioneuston à l'environnement particulier de la microcouche de surfaceLYON1-BU.Sciences (692662101) / SudocBANYULS/MER-Observ.Océanol. (660162201) / SudocSudocFranceF

Exploring practices in collaborative innovation: Unpacking dynamics, relations, and enactment in in-between spaces

In the field of innovation management, the study of collaborative innovation has focused primarily on the type of networks to support innovation, the modularity of the products architecture required to engage actors in collaboration, the strategies for patenting and knowledge appropriation, and the public policies likely to stimulate collaborative innovation. But given that many efforts to collaborate collapse and fail to generate the desired innovative value, previous research needs to be complemented with perspectives on what individuals and collectives actually do when creating collaborative innovation as they engage in "in-between spaces", spaces between actors created by and simultaneously creating social interaction, to understand the practices that both form and constitute the collaboration. Through such studies, new knowledge can be created building on detailed insights about what ensues as different actors engage in interaction to innovate together and contribute to identifying levers to build collaborative spaces that indeed foster innovation. With this special section, we wish to encourage innovation management scholars to rethink their approach to collaborative innovation research by complementing macro-level insights with an exploration of the micro-foundations of collaborative innovation to gain a more nuanced understanding of collaborative dynamics, relations and enactment

Formulation and manufacturing processes of biosourced candles : transition from petrochemical paraffins to paraffins obtained from biosourced products

La fabrication de bougies requiert l’utilisation de paraffines pétrochimiques. Cependant, malgré une demande croissante, les paraffines sont considérées comme des ressources rares où l’approvisionnement devient de plus en plus serré. A cela, s’ajoutent une concurrence grandissante et une augmentation des prix non négligeable. L’objectif de la thèse est donc de substituer les paraffines par des matières premières biosourcées dans de nouvelles formulations bougies. Le raffinage de ces matières jusqu’à la compréhension de leur comportement en mélanges sont étudiés dans cette thèse. La décoloration et la désodorisation sont des étapes clés dans le raffinage des matières premières afin d’éliminer les molécules odorantes et les pigments. Une amélioration de ces deux procédés est réalisée afin de diminuer le temps de réaction et la pureté de la matière première décolorée et désodorisée. La substitution des paraffines par un fort taux d’huile végétale via l’utilisation d’un organogélateur, l’acide 12-hydroxystéarique, est étudiée. L’organogel ainsi formé entraîne une modification multi-échelle de la structure des bougies : modification du réseau cristallin, du comportement thermique et de la combustion. Enfin, le remplacement d’additifs synthétiques par des additifs végétaux est étudié pour montrer leur effet sur la microstructure cristalline et sur le comportement mécanique des mélanges dans lesquels ils sont introduits. Cependant, peu de bénéfices ont été mis en évidence par rapport aux additifs synthétiques.The manufacture of candles requires the use of petrochemical paraffins. However, despite growing demand, paraffins are considered as a scarce resource where supplies are becoming increasingly tight. In addition, there is growing competition and a significant increase of prices. The aim of the thesis is to substitute paraffins with biosourced raw materials in candle formulations. The refining of these materials up to the understanding of their behaviour in mixtures are studied in this thesis. Bleaching and deodorization are key steps in the refining of raw materials in order to eliminate odor molecules and pigments. Both processes are improved in order to reduce the reaction time and the purity of the bleached and deodorized raw material. The substitution of paraffins by a high level of vegetable oil through the use of an organogelator, 12-hydroxystearic acid, is studied. The organogel thus formed leads to a multi-scale modification of the candle structure: modification of the crystal lattice, thermal behaviour and combustion. Finally, the replacement of synthetic additives by vegetable additives is studied to show their effect on the crystalline microstructure and on the mechanical behaviour of mixtures in which they are introduced. However, few benefits are demonstrated compared to synthetic additives

Le patrimoine préhistorique et protohistorique

Plaquette éditée par le Parc Naturel Régional Périgord - Limousin, p. 4-