980 resultados para diverse nature


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Oestrogen produces diverse biological effects through binding to the oestrogen receptor (ER)(1). The ER is a steroid hormone nuclear receptor, which, when bound to oestrogen, modulates the transcriptional activity of target genes(2). Controversy exists, however, concerning whether ER has a role outside the nucleus(3), particularly in mediating the cardiovascular protective effects of oestrogen(4). Here we show that the ER isoform, ER alpha, binds in a ligand-dependent manner to the p85 alpha regulatory subunit of phosphatidylinositol-3-OH kinase (PI(3)K). Stimulation with oestrogen increases ER alpha-associated PI(3)K activity, leading to the activation of protein kinase B/Akt and endothelial nitric oxide synthase (eNOS). Recruitment and activation of PI(3)K by ligand-bound ERa are independent of gene transcription, do not involve phosphotyrosine adapter molecules or src-homology domains of p85 alpha, and extend to other steroid hormone receptors. Mice treated with oestrogen show increased eNOS activity and decreased vascular leukocyte accumulation after ischaemia and reperfusion injury. This vascular protective effect of oestrogen was abolished in the presence of PI(3)K or eNOS inhibitors. Our findings define a physiologically important non-nuclear oestrogen-signalling pathway involving the direct interaction of ERa with PI(3)K.

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KF, LiF and CsF/A(2)O(3) catalysts with different loadings from 1 to 20 wt% were prepared using aqueous solutions of the alkaline fluoride compounds by wet impregnation of basic mesoporous MSU-type alumina. The catalysts were activated under At at 400 degrees C for 2 h and monitored by in situ XRD measurements. The catalysts were also characterized using several techniques: N-2 adsorption/desorption isotherms at -196 degrees C, FTIR, DR-UV-vis, CO2-TPD, XRD, Al-27 CP/MAS NMR. These characterizations led to the conclusion that the deposition of alkaline fluorides on the alumina surface generates fluoroaluminates and aluminate species. The process is definitivated at 400 degrees C. The fluorine in these structures is less basic than in the parent fluorides, but the oxygen becomes more basic. The catalysts were tested for the transesterification of fatty esters under different experimental conditions using conventional heating, microwave and Ultrasound irradiation. Recycling experiments showed that these catalysts are stable for a limited number of cycles. (C) 2009 Elsevier Inc. All rights reserved.

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The potential to use Ionic Liquids (ILs) as novel solvents or fluids for a diverse range of applications has become increasingly rent as researchers in academia and try respond to challenges from atmospheric emissions and disposal of many common solvents by evaluating novel reaction media. The intrinsic non-volatile nature of ILs provides an opportunity to reduce, or even completely eliminate, hazardous and toxic emissions to the atmosphere, thus providing the promise for significant environmental benefits. In synthesis and catalysis, ILs have been used as solvents (or solvents and catalysts), with the greatest current effort on using the ILs as alternatives to VOCs. In contrast, electrochemical studies hove utills'ed the fact that ILs are liquid rather than solids to provide liquid electrolytes without needing to odd an additional solvent. is overview appraiso an appraisal of potential to use ILs in industrial applications, illustrating some areas where practical uses are being developed, and how, throuqh understanding ionic liquids in a conceptuo level, new opportunities ore continuing to evolve.

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This essay examines Norman Mailer's theory of the "commando raid" shooting style that guided his film MAIDSTONE (1970). Mailer's own published commentary is compared with the various narrative and aesthetic concessions he had to make during both the highly-improvised production phase and the tightly-controlled post-production phase.

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The process of divorce as a family change process including outcomes and consequences has received considerable research attention in the western context. However, the experience of divorce for children within specific ethnic contexts has been rather limited leading to poor planning and practice provision with diverse families. By drawing upon an empirical qualitative study of British Indian adult children, this paper will make a case for recognising diverse needs within specific historical, socio-cultural and developmental contexts. There is a need to acknowledge these contexts in policy design to establish practice that is flexible, accessible and relevant to the needs of different and diverse communities. Results indicate that areas of impact may be similar to those identified by other studies within the literature review. However, the experiences, expressions, implications and larger consequences of impact are located within specific socio-cultural contexts. In support of this, major findings of the study (outlined below) will be discussed - Context: patriarchy, stigma, immigration; Impact: economic, social, emotional, career/education, physical; Coping: psychological strategies, physical strategies, social strategies, sources of support.

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This article compares chronologies reconstructed from historical records of prices, wages, grain harvests, and population with corresponding chronologies of growing conditions and climatic variations derived from dendrochronology and Greenland ice-cores. It demonstrates that in pre-industrial, and especially late medieval, England, short-term environmental shocks and more enduring shifts in environmental conditions (sometimes acting in concert with biological agencies) exercised a powerful influence upon the balance struck between population and available resources via their effects upon the reproduction, health and life expectancy of humans, crops, and livestock. Prevailing socio-economic conditions and institutions, in turn, shaped society's susceptibility to these environmental shocks and shifts.

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Gentrification has for too long been investigated as an urban phenomenon. Only relatively recently has it been viewed as an avenue for fruitful rural research. This paper focuses on the repopulation of rural Scotland. Using survey and interview data it examines evidence of gentrification among in-migration flows and seeks to explore both the social transformation of rural areas and the social displacement of rural residents.

The findings point towards important geographical variations. Not all in-migration represents gentrification, and where it does gives rise to very differing impacts. Clear spatial divisions in the local housing market are identified, and evidence is obtained to support a number of differing theoretical debates. Issues of social displacement and population replacement are explored, with the paper tentatively suggesting an important link between urban and rural gentrification processes. Finally, temporal and geographical phases of gentrification are identified. Collectively these findings have direct relevance to how we define gentrification.

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