794 resultados para Music -- Instruction and study -- Research
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This work has been presented in: V Conference AERNA, Faro (Portugal), 30 May 2012-1 June 2012 and IV Workshop on Valuation Methods in Agro-food and Environmental Economics, Castelldefels (Barcelona, Spain), 12 July 2012-13 July 2012.
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Supporting presentation slides to accompany the Janet network end to end performance initiative workshop
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The report provides recommendations to policy makers in science and scholarly research regarding IPR policy to increase the impact of research and make the outcomes more available. The report argues that the impact of publicly-funded research outputs can be increased through a fairer balance between private and public interest in copyright legislation. This will allow for wider access to and easier re-use of published research reports. The common practice of authors being required to assign all rights to a publisher restricts the impact of research outputs and should be replaced by wider use of a non-exclusive licence. Full access and re-use rights to research data should be encouraged through use of a research-friendly licence.
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There is no malaria vaccine currently available, and the most advanced candidate has recently reported a modest 30% efficacy against clinical malaria. Although many efforts have been dedicated to achieve this goal, the research was mainly directed to identify antigenic targets. Nevertheless, the latest progresses on understanding how immune system works and the data recovered from vaccination studies have conferred to the vaccine formulation its deserved relevance. Additionally to the antigen nature, the manner in which it is presented (delivery adjuvants) as well as the immunostimulatory effect of the formulation components (immunostimulants) modulates the immune response elicited. Protective immunity against malaria requires the induction of humoral, antibody-dependent cellular inhibition (ADCI) and effector and memory cell responses. This review summarizes the status of adjuvants that have been or are being employed in the malaria vaccine development, focusing on the pharmaceutical and immunological aspects, as well as on their immunization outcomings at clinical and preclinical stages.
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Several new ligand platforms designed to support iron dinitrogen chemistry have been developed. First, we report Fe complexes of a tris(phosphino)alkyl (CPiPr3) ligand featuring an axial carbon donor intended to conceptually model the interstitial carbide atom of the nitrogenase iron-molybdenum cofactor (FeMoco). It is established that in this scaffold, the iron center binds dinitrogen trans to the Calkyl anchor in three structurally characterized oxidation states. Fe-Calkyl lengthening is observed upon reduction, reflective of significant ionic character in the Fe-Calkyl interaction. The anionic (CPiPr3)FeN2- species can be functionalized by a silyl electrophile to generate (CPiPr3)Fe-N2SiR3. This species also functions as a modest catalyst for the reduction of N2 to NH3. Next, we introduce a new binucleating ligand scaffold that supports an Fe(μ-SAr)Fe diiron subunit that coordinates dinitrogen (N2-Fe(μ-SAr)Fe-N2) across at least three oxidation states (FeIIFeII, FeIIFeI, and FeIFeI). Despite the sulfur-rich coordination environment of iron in FeMoco, synthetic examples of transition metal model complexes that bind N2 and also feature sulfur donor ligands remain scarce; these complexes thus represent an unusual series of low-valent diiron complexes featuring thiolate and dinitrogen ligands. The (N2-Fe(μ-SAr)Fe-N2) system undergoes reduction of the bound N2 to produce NH3 (~50% yield) and can efficiently catalyze the disproportionation of N2H4 to NH3 and N2. The present scaffold also supports dinitrogen binding concomitant with hydride as a co-ligand. Next, inspired by the importance of secondary-sphere interactions in many metalloenzymes, we present complexes of iron in two new ligand scaffolds ([SiPNMe3] and [SiPiPr2PNMe]) that incorporate hydrogen-bond acceptors (tertiary amines) which engage in interactions with nitrogenous substrates bound to the iron center (NH3 and N2H4). Cation binding is also facilitated in anionic Fe(0)-N2 complexes. While Fe-N2 complexes of a related ligand ([SiPiPr3]) lacking hydrogen-bond acceptors produce a substantial amount of ammonia when treated with acid and reductant, the presence of the pendant amines instead facilitates the formation of metal hydride species.
Additionally, we present the development and mechanistic study of copper-mediated and copper-catalyzed photoinduced C-N bond forming reactions. Irradiation of a copper-amido complex, ((m-tol)3P)2Cu(carbazolide), in the presence of aryl halides furnishes N-phenylcarbazole under mild conditions. The mechanism likely proceeds via single-electron transfer from an excited state of the copper complex to the aryl halide, generating an aryl radical. An array of experimental data are consistent with a radical intermediate, including a cyclization/stereochemical investigation and a reactivity study, providing the first substantial experimental support for the viability of a radical pathway for Ullmann C-N bond formation. The copper complex can also be used as a precatalyst for Ullmann C-N couplings. We also disclose further study of catalytic Calkyl-N couplings using a CuI precatalyst, and discuss the likely role of [Cu(carbazolide)2]- and [Cu(carbazolide)3]- species as intermediates in these reactions.
Finally, we report a series of four-coordinate, pseudotetrahedral P3FeII-X complexes supported by tris(phosphine)borate ([PhBP3FeR]-) and phosphiniminato X-type ligands (-N=PR'3) that in combination tune the spin-crossover behavior of the system. Low-coordinate transition metal complexes such as these that undergo reversible spin-crossover remain rare, and the spin equilibria of these systems have been studied in detail by a suite of spectroscopic techniques.
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In June, 1961, discussions were held in London to consider the future of the East Africa High Commission Services. It was agreed that the functions of the East Africa High Commission, with the exception of Defence, should be transfered to the East African Common Services Organization, which was subsequently established on 9th December, 1961, on the achievement of independence by Tanganyika. The Common Services Organization is controlled by an Authority, consisting of the principal elected Minister in each of the East African territories, which is responsible for the overall policy and direction of the Organization. The Authority is assisted by four Ministerial Committees, of which one is responsible for the Social and Research Services of the Organization
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Marine line-fishing is seen to be of major importance to the social well-being and economy of many coastal people of Mozambique. Aspects of the artisanal and semi-industrial fisheries of Mozambique are described and a recent significant increase in effort is noted. Landings are seen to comprise a high proportion of vulnerable, endemic species, several of which are shared with neighbouring South Africa. Trends in CPUE, sex ratios and yield per recruit suggest that future landings may decline if conservative management is not introduced. Strategies for data collection and biological research on key species are proposed.