128 research outputs found

    Anisotropy of the gap energy in high Tc Copper Oxides

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    Within the frame work of BCS phonon-mediated pairing with a logarithmic (2D) Van Hove Singularity in the density of states, we study the anisotropy of superconductors gap taking into account the anisotropy of attractive coupling and the coulomb repulsion .The results show that gap is more disperse and can explain some observed experimental data.Within the frame work of BCS phonon-mediated pairing with a logarithmic (2D) Van Hove Singularity in the density of states, we study the anisotropy of superconductors gap taking into account the anisotropy of attractive coupling and the coulomb repulsion .The results show that gap is more disperse and can explain some observed experimental data

    Risk assessment of mercury and methyl mercury intake via sardine and swordfish consumption in Algeria

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    NO ABSTRACT AVAILABLETotal mercury (Hg) and methylmercury (MeHg) concentrations in the flesh of sardine (Sardina pilchardus) and swordfish (Xiphias gladius) fished in three Algerian coasts were determined by a direct mercury analyzer (DMA). We also assessed the risk to which the consumer was exposed to by calculating the estimated daily intakes (EDIs), target hazard quotient (THQ) and hazard index (HI). The average concentrations of Hg and MeHg in the flesh of sardine were similar (0.04 mg/kg wet weight) and in swordfish were 0.61 mg/kg wet weight; 0.57 mg/kg wet weight, respectively. These concentrations have not surpassed the thresholds set by the Algerian and European regulations. The estimated daily intakes for Hg and MeHg were similar in sardine (0.0064 ÎŒg/kg/day) and were 0.098 ÎŒg/kg/day and 0.092 ÎŒg/kg/day for Hg and MeHg, respectively, in swordfish. These values did not exceed the provisional tolerable weekly intake (PTWI) established by the European Food Safety Authority (EFSA) and by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The target hazard quotient (THQ) and the hazard index (HI) calculated were < 1. Consequently, consumption of these fishes does not pose any risk for the adult groups of the Algerian population regarding mercury, and methylmercury studied

    Monoclinic polymorph of poly[[di-Ό-aqua-triaquadi-Ό-oxalato-barium(II)­copper(II)] monohydrate]

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    A monoclinic polymorph of the title compound, {[BaCu(C2O4)2(H2O)5]·H2O}n, is reported. The structure is best described as a coordination polymer where the CuII and BaII centers are coordinated by five and nine O atoms, respectively, in capped quadratic antiprismatic and tetragonal pyramidal geometries. The polymerization arises due to the presence of bridging mono- and bidentate oxalate ligands as well as bridging water mol­ecules. The crystal structure is consolidated by a three-dimensional network of hydrogen bonding

    Traitement peu invasif d’une breche osteo meningee associee a une hypertension intracranienne benigne

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    Description L’hypertension intracrĂąnienne bĂ©nigne (HTICB) est une augmentation anormale de la pression intracrĂąnienne non associĂ©e Ă  un processus occupant de l’espace intracrĂąnien, une thrombose des veinescĂ©rĂ©brales ou une hydrocĂ©phalie. CaractĂ©risĂ©e par des cĂ©phalĂ©es invalidantes, des acouphĂšnes pulsatiles, elle peut avoir une Ă©volution pĂ©jorative et irrĂ©versible entraĂźnant une cĂ©citĂ©. La survenue d’une rhinorrhĂ©e spontanĂ©e dans un contexte d’HTICB a Ă©tĂ© dĂ©crite dans la littĂ©rature mais demeure peu frĂ©quente. Objectif et cas cliniqueNous rapportons le cas d’une femme obĂšse ĂągĂ©e de 40 ans, qui a Ă©tĂ© admise pour rhinorrhĂ©e droite spontanĂ©e. Les explorations neuroradiologiques ont permis d’évoquer une hypertension intracrĂąnienne bĂ©nigne sur une brĂšche ethmoĂŻdale antĂ©rieure. Le monitoring de la pression a confirmĂ© le diagnostic. Elle abĂ©nĂ©ficiĂ© d’une dĂ©rivation ventriculo pĂ©ritonĂ©ale. L’évolution est favorable (disparition des symptĂŽmes) avec un delai de recul de 16 mois . Conclusion L’HTICB est une pathologie avec des consĂ©quences irrĂ©versibles si le traitement n’est pas adĂ©quat et rapide. En cas de rhinorrhĂ©e isolĂ©e dans le cadre de l’hypertension intracrĂąnienne bĂ©nigne la dĂ©rivation ventriculo pĂ©ritonĂ©ale est une attitude thĂ©rapeutique simple mais efficace

    Investigation of Rheological and Geometric Properties Effect on Nonlinear Behaviour of Fluid Viscous Dampers

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    Global approval of the use of fluid viscous dampers to control the buildings response against dynamic loadings is growing. The idea behind incorporating additional dampers is that they will reduce most of the energy that is transmitted to the building during shaking event. The objective of this work is to identify and enhance the design parameters that control the nonlinear behaviour of fluid viscous damper subjected to sinusoidal excitation. For this, a numerical model of the flow inside the dissipater has been carried out based on finite volume method. A novel approach has been adopted to simulate elastic behaviour of the fluid, taking into account its compressibility by using the Murnaghan equation of state. A comparison between the calculations of the proposed model and the experimental tests was carried out. The model proved to be sufficiently accurate. A fluid flow analysis was then conducted to fully understand the internal mechanism of the damper. A parametric study was then performed by varying aspects such as dimensions, geometric relationships between components and fluid properties in order to better understand their effect on the non-linear behaviour of the device.  The results highlight the relationship between the parameters governing the shear thinning behaviour of the fluid and the non-linearity exponent of the damper. This makes it possible to better control the non-linear behaviour of the device by selecting the appropriate silicone oil and the appropriate geometric dimensions of its components

    Impacts and social implications of landuse-environment conflicts in a typical Mediterranean watershed

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    In coastal watersheds, services and landuse favour coastal tourism and urbanization, depriving rural upstream of infrastructure and attention. This unbalanced management leads to an intensification of socioeconomic changes that generate a structural heterogeneity of the landscape and a reduction in the livelihoods of the rural population. The incessant dissociation between the objectives of the stakeholders triggers landuse-environment-economy conflicts which threaten to mutate large-scale development programs. Here, we used multi-assessment techniques in a Mediterranean watershed from Morocco to evaluate the effects of landuse change on water, vegetation, and perception of the rural population towards environmental issues. We combined complementary vegetation indexes (NDVI and EVI) to study long-term landuse change and phenological statistical pixel-based trends. We assessed the exposure of rural households to the risk of groundwater pollution through a water analysis supplemented by the calculation of an Integrated Water Quality Index. Later, we contrasted the findings with the results of a social survey with a representative sample of 401 households from 7 villages. We found that rapid coastal linear urbanization has resulted in a 12-fold increase in construction over the past 35 years, to the detriment of natural spaces and the lack of equipment and means in rural areas upstream. We show that the worst water qualities are linked to the negative impact of anthropogenic activities on immediately accessible water points. We observe that rural households are aware of the existence and gravity of environmental issues but act confusedly because of their low education level which generates a weak capacity to understand cause and effect relationships. We anticipate the pressing need to improve the well-being and education of the population and synergistically correct management plans to target the watershed as a consolidated system. Broadly, stakeholders should restore lost territorial harmony and reallocate landuse according to a sustainable environment-socioeconomic vision

    ANEVRISMES GEANTS DE L’ARTERE HYPOGASTRIQUE : DIFFICULTES DE PRISE EN CHARGE THERAPEUTIQUE

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    The isolated aneurysms of internal iliac artery are rare and present several difficulties of care. Their treatment is often difficult and contains relatively high rates of morbidity and mortality. The giant character complicates the methods of assessment and surgical dissection due in the complexity of the anatomical region and the modifications of marks engendered by the aneurismal mass. Bringing back us to two observations of giants’ aneurisms of the internal iliac artery discovered incidentally on an atypical symptomatology. Both patients were surgically handled with a good evolution. We evoke the variety of the aetiologies of these aneurysms and we discuss the difficulties of their surgical treatment.Les anĂ©vrismes isolĂ©s de l’artĂšre iliaque interne sont rares et prĂ©sentent plusieurs difficultĂ©s de prise en charge. Leur traitement est souvent difficile et comportent des taux de morbiditĂ© et de mortalitĂ© relativement Ă©levĂ©s. Leur caractĂšre gĂ©ant complique les modalitĂ©s de contrĂŽle et de dissection chirurgicale du Ă  la complexitĂ© de la rĂ©gion anatomique et les modifications des repĂšres engendrĂ©es par la masse anĂ©vrismale. Nous rapportons deux observations d’anĂ©vrismes gĂ©ants de l’artĂšre iliaque interne dĂ©couverts fortuitement sur une symptomatologie atypique. Les deux malades ont Ă©tĂ© traitĂ©s chirurgicalement avec une bonne Ă©volution. Nous Ă©voquons la diversitĂ© des Ă©tiologies de ces anĂ©vrismes et nous discutons les difficultĂ©s de leur traitement chirurgical
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