899 resultados para Site U1385


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Le site moustérien de la Grotte du Bison est situé au cœur des grottes préhistoriques longeant la rivière de la Cure à Arcy-sur-Cure (Yonne, France). La couche I-J de ce gisement représente une occupation néandertalienne datant de la fin du stade isotopique 4 (MIS 4) et du début du stade 3. Face à l’instabilité du climat durant cette période, les groupes de chasseurs-cueilleurs néandertaliens doivent faire des choix en matière d’acquisition des ressources alimentaires. Le mode de subsistance de ces groupes implique des choix stratégiques de comportements de chasse, de transport et de traitement des carcasses, ainsi que de mobilité de groupe. Quelles sont les stratégies d’exploitation de la faune employées par les Néandertaliens à Arcy-sur-Cure il y a un peu plus de 50 000 ans? Ce mémoire présente une analyse archéozoologique de l’assemblage faunique mis au jour durant la mission de fouilles 2014. Les résultats indiquent que les populations néandertaliennes ont occupé le site de façon saisonnière en alternance avec d’autres animaux carnivores comme l’ours des cavernes et la hyène des cavernes. Les hyènes et les Néandertaliens sont deux potentiels agents accumulateurs d’ossements dans la grotte. Un regard taphonomique sur l’assemblage faunique de la couche I-J suggère que les groupes néandertaliens ont chassé le renne et le cheval, alors que les meutes de hyènes ont accumulé des ossements de bovinés et de chevaux. Les groupes néandertaliens de la Grotte du Bison ont rapporté les carcasses entières de leurs proies sur le site. Ils en ont exploité la viande, la moelle, les peaux, ont fabriqué des outils en os et ont utilisé les plumes des rapaces, vraisemblablement à des fins symboliques.

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Soil fertility constraints to crop production have been recognized widely as a major obstacle to food security and agro-ecosystem sustainability in sub-Saharan West Africa. As such, they have led to a multitude of research projects and policy debates on how best they should be overcome. Conclusions, based on long-term multi-site experiments, are lacking with respect to a regional assessment of phosphorus and nitrogen fertilizer effects, surface mulched crop residues, and legume rotations on total dry matter of cereals in this region. A mixed model time-trend analysis was used to investigate the effects of four nitrogen and phosphorus rates, annually applied crop residue dry matter at 500 and 2000 kg ha^-1, and cereal-legume rotation versus continuous cereal cropping on the total dry matter of cereals and legumes. The multi-factorial experiment was conducted over four years at eight locations, with annual rainfall ranging from 510 to 1300 mm, in Niger, Burkina Faso, and Togo. With the exception of phosphorus, treatment effects on legume growth were marginal. At most locations, except for typical Sudanian sites with very low base saturation and high rainfall, phosphorus effects on cereal total dry matter were much lower with rock phosphate than with soluble phosphorus, unless the rock phosphate was combined with an annual seed-placement of 4 kg ha^-1 phosphorus. Across all other treatments, nitrogen effects were negligible at 500 mm annual rainfall but at 900 mm, the highest nitrogen rate led to total dry matter increases of up to 77% and, at 1300 mm, to 183%. Mulch-induced increases in cereal total dry matter were larger with lower base saturation, reaching 45% on typical acid sandy Sahelian soils. Legume rotation effects tended to increase over time but were strongly species-dependent.

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A revolution\0\0\0 in earthmoving, a $100 billion industry, can be achieved with three components: the GPS location system, sensors and computers in bulldozers, and SITE CONTROLLER, a central computer system that maintains design data and directs operations. The first two components are widely available; I built SITE CONTROLLER to complete the triangle and describe it here. SITE CONTROLLER assists civil engineers in the design, estimation, and construction of earthworks, including hazardous waste site remediation. The core of SITE CONTROLLER is a site modelling system that represents existing and prospective terrain shapes, roads, hydrology, etc. Around this core are analysis, simulation, and vehicle control tools. Integrating these modules into one program enables civil engineers and contractors to use a single interface and database throughout the life of a project.

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L’estudi de l’Anàlisi del Cicle de Vida (ACV) ha estat realitzat a l’empresa CRODA Ibèrica S.A - Mevisa Site, en concret a la línia productiva on s’hi fabrica el monoestearat de glicerina utilitzant una eina informàtica comercial denominada SIMAPRO que analitza i compara els aspectes mediambientals d’un producte d’una manera sistemàtica i consistent seguint les recomanacions de les normes ISO 14040

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Step by step guide.

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Synthetic vaccines constitute the most promising tools for controlling and preventing infectious diseases. When synthetic immunogens are designed from the pathogen native sequences, these are normally poorly immunogenic and do not induce protection, as demonstrated in our research. After attempting many synthetic strategies for improving the immunogenicity properties of these sequences, the approach consisting of identifying high binding motifs present in those, and then performing specific changes on amino-acids belonging to such motifs, has proven to be a workable strategy. In addition, other strategies consisting of chemically introducing non-natural constraints to the backbone topology of the molecule and modifying the a-carbon asymmetry are becoming valuable tools to be considered in this pursuit. Non-natural structural constraints to the peptide backbone can be achieved by introducing peptide bond isosters such as reduced amides, partially retro or retro-inverso modifications or even including urea motifs. The second can be obtained by strategically replacing L-amino-acids with their enantiomeric forms for obtaining both structurally site-directed designed immunogens as potential vaccine candidates and their Ig structural molecular images, both having immunotherapeutic effects for preventing and controlling malaria.

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Se desarrolla un proyecto de innovación educativa que se plantea para fomentar el conocimiento y el uso de la tecnologías de la información y la comunicación entre el profesorado y el alumnado. Se intenta mejorar el desarrollo educativo del alumnado y la cohesión de la comunidad educativa, así como aumentar la eficacia en el cumplimiento de la función social como centro público de enseñanza. El proyecto se estructura en tres fases: análisis de las necesidades de comunicación institucional, información administrativa, participación didáctica para el alumnado y profesorado y participación cultural para la comarca; realización de páginas que componen las diferentes secciones que incluye la realización de las imágenes y contenidos multimedia necesarios para componer las páginas; recopilación e incorporación de información, documentación, materiales didácticos y contenidos culturales. El diseño del Web-Site intenta recoger toda la información que resulte útil a la comunidad educativa, por ello se realizan evaluaciones de su contenido periódicamente. El trabajo de cada uno de los miembros del grupo es evaluado por el resto de los compañeros, y es presentando cada trimestre al equipo directivo. El equipo directivo valora como muy bueno y de calidad el trabajo desarrollado en el proyecto de innovación.

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The electron hole transfer (HT) properties of DNA are substantially affected by thermal fluctuations of the π stack structure. Depending on the mutual position of neighboring nucleobases, electronic coupling V may change by several orders of magnitude. In the present paper, we report the results of systematic QM/molecular dynamic (MD) calculations of the electronic couplings and on-site energies for the hole transfer. Based on 15 ns MD trajectories for several DNA oligomers, we calculate the average coupling squares 〈 V2 〉 and the energies of basepair triplets X G+ Y and X A+ Y, where X, Y=G, A, T, and C. For each of the 32 systems, 15 000 conformations separated by 1 ps are considered. The three-state generalized Mulliken-Hush method is used to derive electronic couplings for HT between neighboring basepairs. The adiabatic energies and dipole moment matrix elements are computed within the INDO/S method. We compare the rms values of V with the couplings estimated for the idealized B -DNA structure and show that in several important cases the couplings calculated for the idealized B -DNA structure are considerably underestimated. The rms values for intrastrand couplings G-G, A-A, G-A, and A-G are found to be similar, ∼0.07 eV, while the interstrand couplings are quite different. The energies of hole states G+ and A+ in the stack depend on the nature of the neighboring pairs. The X G+ Y are by 0.5 eV more stable than X A+ Y. The thermal fluctuations of the DNA structure facilitate the HT process from guanine to adenine. The tabulated couplings and on-site energies can be used as reference parameters in theoretical and computational studies of HT processes in DNA

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