998 resultados para Critical doses


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This paper is written by democratic educators who stand for the idea that is it worth developing, through classrooms and schools, a socially just (egalitarian), anti-discriminatory society where interdependent relationships are valued. This paper significantly develops some of the ideas explored in the authors’ earlier contribution concerned with progress in Northern Ireland towards educational inclusion, and how this might more effectively advance in a post-conflict transforming society. In particular, the paper poses the ‘so what’ question, and it responds by exploring the practical implications of six key ideas thought essential for transforming learning environments supportive of cultural diversity, equity and excellence for all. In addition, it includes examples of how school staff, along with collaborating partners, might utilize these key principles in order to facilitate school improvement.

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The attempt to connect philosophy and social hope has been one of the key distinguishing features of critical theory as a tradition of enquiry. This connection has been questioned forcefully from the perspective of a post-philosophical pragmatism, as articulated by Rorty. In this article I consider two strategies that have been adopted by critical theorists in seeking to reject Rorty's suggestion that we should abandon the attempt to ground social hope in philosophical reason. We consider argumentative strategies of the philosophical anthropologist and of the rational proceduralist. Once the exchanges between Rorty and these two strands of critical theory have been reconstructed and assessed, an alternative perspective emerges. It is argued that philosophical reasoning best helps to sustain social hope in a rapidly changing world when we consider it in terms of the practice of democratic criticism.

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Genetic or vitamin D3-induced overexpression of thymic stromal lymphopoietin (TSLP) by keratinocytes results in an atopic dermatitis (AD)-like inflammatory phenotype in mice echoing the discovery of high TSLP expression in epidermis from AD patients. Although skin dendritic cells (DC) are suspected to be involved in AD, direct evidence of a pathogenetic role for skin DC in TSLP-induced skin inflammation has not yet been demonstrated. In a mouse model of AD, i.e. mice treated with the low-calcemic vitamin D3 analogue, MC903, we show that epidermal Langerhans cells (LC)-depleted mice treated with MC903 do neither develop AD-like inflammation nor increased serum IgE as compared to vitamin D3 analogue-treated control mice. Accordingly, we show that, in mice treated with MC903 or in K14-TSLP transgenic mice, expression of maturation markers by LC is increased whereas maturation of dermal DC is not altered. Moreover, only LC are responsible for the polarization of naive CD4+ T cells to a Th2 phenotype, i.e. decrease in interferon-gamma and increase in interleukin (IL)-13 production by CD4+ T cells. This effect of LC on T-lymphocytes does not require OX40-L/CD134 and is mediated by a concomitant down-regulation of IL-12 and CD70. Although it was previously stated that TSLP up-regulates the production of thymus and activation-regulated chemokine (TARC)/chemokine (C-C motif) ligand 17 (CCL17) and macrophage-derived chemokine (MDC)/CCL22 by human LC in vitro, our work shows that production of these Th2- cell attracting chemokines is increased only in keratinocytes in response to TSLP overexpression. These results demonstrate that LC are required for the development of AD in mouse models of AD involving epidermal TSLP overexpression.

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There is a growing interest in critical realism and its application to social work. This article makes a case for adopting this philosophical position in qualitative social work research. More specifically, it suggests that there is a concordance between critical realist premises and action research with its cyclical inquiry and advancement of social change. This combination of philosophy and method, it is argued, promotes anti-oppressive social work research and illuminates the processes shaping outcomes in programme evaluations. Overall, the article underscores the importance of 'depth' in qualitative inquiry by conceiving the social world in terms of five interlacing, social domains.

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The marine oligotrophic ultramicrobacterium Sphingomonas alaskensis RB2256 has a physiology that is distinctly different from that of typical copiotrophic marine bacteria, such as Vibrio angustum S14. This includes a high level of inherent stress resistance and the absence of starvation-induced stress resistance to hydrogen peroxide. In addition to periods of starvation in the ocean, slow nutrient-limited growth is likely to be encountered by oligotrophic bacteria for substantial periods of time. In this study we examined the effects of growth rate on the resistance of S. alaskensis RB2256 to hydrogen peroxide under carbon or nitrogen limitation conditions in nutrient-limited chemostats. Glucose-limited cultures of S. alaskensis RB2256 at a specific growth rate of 0.02 to 0.13 h(-1) exhibited 10,000-fold-greater viability following 60 min of exposure to 25 mM hydrogen peroxide than tells growing at a rate of 0.14 h(-1) or higher. Growth rate control of stress resistance was found to be specific to carbon and energy limitation in this organism. In contrast, V. angustum S14 did not exhibit growth rate-dependent stress resistance. The dramatic switch in stress resistance that was observed under carbon and energy limitation conditions has not been described previously in bacteria and thus may be a characteristic of the oligotrophic ultramicrobacterium, Catalase activity varied marginally and did not correlate with the growth rate, indicating that hydrogen peroxide breakdown was not the primary mechanism of resistance. More than 1,000 spots were resolved on silver-stained protein gels for cultures growing at rates of 0.026, 0.076, and 0.18 h(-1). Twelve protein spots had intensities that varied by more than twofold between growth rates and hence are likely to be important for growth rate-dependent stress resistance. These studies demonstrated the crucial role that nutrient limitation plays in the physiology of S. alaskensis RB2256, especially under oxidative stress conditions.

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Data from a series of controlled suction triaxial tests on samples of compacted speswhite kaolin were used in the development of an elasto–plastic critical state framework for unsaturated soil. The framework is defined in terms of four state variables: mean net stress, deviator stress, suction and specific volume. Included within the proposed framework are an isotropic normal compression hyperline, a critical state hyperline and a state boundary hypersurface. For states that lie inside the state boundary hypersurface the soil behaviour is assumed to be elastic, with movement over the state boundary hypersurface corresponding to expansion of a yield surface in stress space. The pattern of swelling and collapse observed during wetting, the elastic–plastic compression behaviour during isotropic loading and the increase of shear strength with suction were all related to the shape of the yield surface and the hardening law defined by the form of the state boundary. By assuming that constant–suction cross–sections of the yield surface were elliptical it was possible to predict test paths for different types of triaxial shear test that showed good agreement with observed behaviour. The development of shear strain was also predicted with reasonable success, by assuming an associated flow rule.

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Aminolaevulinic acid (ALA) is known to poorly penetrate into thick lesions, such as nodular basal cell carcinomas Short chain ALA esters, possessing increased lipophilicity relative to their hydrophilic parent, have previously been shown to be highly efficient at inducing protoporphyrin IX (PpIX) production in cell culture, at equimolar concentrations. In contrast, in vitro skin permeation and in vivo animal studies, which up to now have compared prodrugs on a % w/vv basis, have failed to demonstrate such benefits For the first time, equimolar concentrations of ALA, methyl-ALA (m-ALA) and hexyl-ALA (h-ALA) have been incorporated into an o/w cream preparation. In vitro penetration studies into excised porcine skin revealed that increased levels of h-ALA, compared to ALA and m-ALA were found in the upper skin layers, at all drug loadings studied. Topical application of the formulations to nude murine skin in vivo, revealed that creams containing h-ALA induced significantly higher levels of peak PpIX fluorescence (F-max = 289.0) at low concentrations compared to m-ALA (F-max = 159.2) and ALA (F-max = 191 9). Importantly, this study indicates that when compared on an equimolar basis, h-ALA has improved skin penetration, leading to enhanced PpIX production compared to the parent drug and m-ALA (C) 2010 Wiley-Liss, Inc and the American Pharmacists Association J Pharm Sci 99 3486-3498, 2010