999 resultados para 1470
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The asymmetric Diels-Alder reaction between N-acryloyloxazolidinone and cyclopentadiene and the Mukaiyama-aldol reaction between methylpyruvate and 1-phenyl-1-trimethylsilyloxyethene have been catalysed by heterogeneous copper(II)-bis(oxazoline)-based polymer immobilised ionic liquid phase (PIILP) systems generated from a range of linear and cross linked ionic polymers. In both reactions selectivity and ee were strongly influenced by the choice of polymer. A comparison of the performance of a range of Cu(II)-bis(oxazoline)-PIILP catalyst systems against analogous supported ionic liquid phase (SILP) heterogeneous catalysts as well as their homogeneous counterparts has been undertaken and their relative merits evaluated.
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In this paper, we present a novel discrete cosine transform (DCT) architecture that allows aggressive voltage scaling for low-power dissipation, even under process parameter variations with minimal overhead as opposed to existing techniques. Under a scaled supply voltage and/or variations in process parameters, any possible delay errors appear only from the long paths that are designed to be less contributive to output quality. The proposed architecture allows a graceful degradation in the peak SNR (PSNR) under aggressive voltage scaling as well as extreme process variations. Results show that even under large process variations (±3σ around mean threshold voltage) and aggressive supply voltage scaling (at 0.88 V, while the nominal voltage is 1.2 V for a 90-nm technology), there is a gradual degradation of image quality with considerable power savings (71% at PSNR of 23.4 dB) for the proposed architecture, when compared to existing implementations in a 90-nm process technology. © 2006 IEEE.
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Dipeptidyl peptidase 4 (DPP-4) enzymatically inactivates incretin hormones, and DPP-4 inhibitor drugs are clinically approved therapies for type 2 diabetes. The primary substrates of DPP-4 are produced in the intestinal lining and we therefore investigated whether lactobacilli colonizing the gut can inhibit this enzyme. Fifteen Lactobacillus strains (Lb 1-15) from human infant faecal samples were isolated, identified, extracted and screened for inhibitory activity against DPP-4. Activity was compared against Lactobacillus reference strains (Ref 1-7), a Gram positive control (Ctrl 1) and two Gram negative controls (Ctrl 2-3). A range of DPP-4 inhibitory activity was observed (10-32%; P<0.05-0.001). Strains of L. fabifermentans (25%), L. plantarum (12-24%) and L. fermentum (14%) had significant inhibitory activity. However, we also noted that E. coli (Ctrl 2) and S. Typhimurium (Ctrl 3) had the greatest inhibitory activity (30-32%). Contrastingly, some isolates (Lb 12-15) and reference cultures (Ref 1-4) instead of inhibiting DPP-4 actually enhanced it, perhaps indicating the presence of X-prolyl-dipeptidyl-amino-peptidase (PepX). This provides a future rationale for using probiotic bacteria or their components for management of type 2 diabetes via DPP-4 inhibition.
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O presente relatório, no âmbito do Mestrado em Educação Pré-Escolar realizado na Escola Superior de Educação do Instituto Politécnico de Santarém, está dividido em três partes. A primeira parte é dedicada aos estágios em dois contextos, o de Creche e o de Jardim-de-Infância e refere-se aos trabalhos e projetos desenvolvidos, ao percurso profissional, aprendizagens realizadas, dificuldades sentidas e reflexões que daí decorreram. A segunda parte refere-se à componente investigativa “A entrada na Creche e as primeiras interações entre crianças: contributos do educador de infância para uma sociabilidade prazerosa”, apresentando um estudo sobre as interações infantis aquando da entrada na creche e sobre a importância que o educador tem neste processo, favorecendo momentos de interações positivas e mediando os problemas que vão surgindo. O estudo realizado é de natureza qualitativa, centrando-se em observações feitas em creche e na reflexão e discussão assentes nessas observações. A terceira parte, considerações finais, sintetiza o percurso realizado e o seu contributo para o desenvolvimento e crescimento pessoal e profissional.
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A review of 'Cartographies of Time: a history of the timeline' by Daniel Rosenberg and Anthony Grafton. Princeton, NJ: Princeton Architectural Press, 2010. (272pp. ISBN: 9781568987637). Keywords: timeline, chronographics
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Nach einer kurzen Einführung in die Themen Angst und Stress wird der Zusammenhang zwischen Stress und Leistung dargestellt. Abschließend werden Lösungsmöglichkeiten für Personen mit Prüfungsangst vorgestellt.
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Tese de doutoramento, Geologia (Geologia Económica e do Ambiente), Universidade de Lisboa, Faculdade de Ciências, 2014
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The article This is Live this is now (2011), contextualises the performance Under the Covers (2009) by Zoo Indigo. The journal article is written by Ildiko Rippel on behalf of Zoo Indigo theatre company (Rosie Garton and Ildiko Rippel) and it is published in the online Body, Space and Technology Journal:
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This paper outlines a theoretical framework which offers an explanation of the complexity of how teachers define their effectiveness in relation to their classroom practice. The research from which this framework emerged was a two-year, mixed method study of 81 primary and secondary school teachers. The use of repertory grid interviews combined with a number of other methods is unique in a study of teachers’ practice and, from the elicited constructs, seven key themes emerged. These themes, analysed in relation to three broad career phases, indicate a number of issues important for teachers as they transfer from early-to-late career.
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Generative divergent analysis (GDA) is a creative additive approach to raising insignificant details of experience to significance. A schematic view of the model highlights use of evocative objects as starting point for ‘turning towards’, ‘turning away’ and ‘being-in-relation-to’ as part of an ongoing burgeoning of experience.The model is exemplified by focusing on a wicker settee as an evocative object that was noticed in an early-years reception class. Revisiting the object generated several speculative ideas relating to the hidden curriculum and energies of childhood. Poetry and song were used during the revisiting in order to develop a more direct experience in addition to the more contemplative awareness that was evoked during the first encounters. As an additive process the outcome of GDA takes the form of unfinished resources for thinking.
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A legacy emphasis was one of the fundamental pillars of the London 2012 Olympic Games. The notion of an Olympic legacy was predicated on assumptions that the event’s value would not purely derive from the sporting spectacle, but rather, from the ‘success’ of enduring effects met out in London and across the country. For physical education students and practitioners, Olympic legacy agendas translated into persistent pressure to increase inspiration, engagement, participation and performance in the subject, sport and physical activity. Responding to this context, and cogniscent of significant disciplinary scholarship, this paper reports initial data from the first phase of a longitudinal study involving Key Stage Three (students aged 11-13) cohorts in two comparable United Kingdom schools: the first an inner-city (core) London school adjacent to the Olympic Park in Stratford, East London (n=150); the second, a (peripheral) school in the Midlands (n=198). The research involved the use of themed questionnaires focusing on self-reported attitudes toward the Olympic Games, and, experiences of physical education, sport and physical activity. Students from both schools demonstrated a wide variety of attitudes toward physical education and sport; yet, minor variances emerged regarding extreme enthusiasm levels. Both cohorts also expressed considerably mixed feelings toward the impending Olympic Games. Strong and variable responses were also reported regarding inspiration levels, ticketing acquisition and engagement levels. Consequently, this investigation can be read within the broader context of legacy debates, and, aligns well with physical educationalists’ on-going discomfort regarding legacy imperatives being enforced upon the discipline and its practitioners. Our work reiterates a shared disciplinary scepticism that while an Olympic Games may temporarily affect young peoples’ affectations for sport (and maybe physical education and physical activity), it may not provide the best, or most appropriate, mechanism for sustained attitudinal and/or social changes en masse.
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This article argues that the emergence of a trans-disciplinary discourse of ‘visual culture’ must be understood as, above all, a constitutively urban phenomenon. More specifically, it is in the historically new form of the capitalist metropolis, as described most famously by Simmel, that the ‘hyper-stimulus’ of modern visual culture has its social and spatial conditions. Paradoxically, however, it is as a result of this that visual culture studies is also intrinsically ‘haunted’ by a certain spectre of the invisible: one rooted in those forms of ‘real abstraction’ which Marx identifies with the commodity and the money form. Considering, initially, the canonical urban visual forms of the collage and the spectacle, these are each read in a certain relation to Simmel’s account of metropolitan life and of the money form, and, through this, to what the author claims are those forms of social and spatial abstraction that must be understood to animate them. Finally, the article returns to the entanglement of the visible and invisible entailed by this, and concludes by making some tentative suggestions about something like a paradoxical urban ‘aesthetic’ of abstraction on such a basis.
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In the present study, we evaluated stimulation of the angiotensin type 2 receptor (AT2R) by the selective non-peptide agonist Compound 21 (C21) as a novel therapeutic concept for the treatment of multiple sclerosis using the model of experimental autoimmune encephalomyelitis (EAE) in mice. C57BL-6 mice were immunized with myelin-oligodendrocyte peptide and treated for 4 weeks with C21 (0.3 mg/kg/day i.p.). Potential effects on myelination, microglia and T-cell composition were estimated by immunostaining and FACS analyses of lumbar spinal cords. The in vivo study was complemented by experiments in aggregating brain cell cultures and microglia in vitro. In the EAE model, treatment with C21 ameliorated microglia activation and decreased the number of total T-cells and CD4+ T-cells in the spinal cord. Fluorescent myelin staining of spinal cords further revealed a significant reduction in EAE-induced demyelinated areas in lumbar spinal cord tissue after AT2R stimulation. C21-treated mice had a significantly better neurological score than vehicle-treated controls. In aggregating brain cell cultures challenged with lipopolysaccharide (LPS) plus interferon-γ (IFNγ), AT2R stimulation prevented demyelination, accelerated re-myelination and reduced the number of microglia. Cytokine synthesis and nitric oxide production by microglia in vitro were significantly reduced after C21 treatment. These results suggest that AT2R stimulation protects the myelin sheaths in autoimmune central nervous system inflammation by inhibiting the T-cell response and microglia activation. Our findings identify the AT2R as a potential new pharmacological target for demyelinating diseases such as multiple sclerosis.