994 resultados para Stimmer, Tobias, 1539-1584.


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N-(aminoalkyl)-4-chloronaphthalene-
1,8-dicarboximides 1, N-
(aminoalkyl)-4-acetamidonaphthalene-
1,8-dicarboximides 3 and N,N'-bis(aminoalkyl)-
perylene-3,4:9,10-tetracarboxydiimides
4 show good fluorescent off ±
on switching in aqueous alcoholic solution
with protons as required for fluorescent
PET sensor design. The excitation
wavelengths lie in the ultraviolet
(lmaxˆ345 and 351 nm) for 1 and 3 and
in the blue-green (lmaxˆ528, 492 and
461 nm) for 4; the emission wavelengths
lie in the violet (lmaxˆ408 nm) for 1, in
the blue (lmaxˆ474 nm) for 3 and in the
yellow-orange (lmaxˆ543 and 583 nm)
for 4. Compound 4b shows substantial
fluorescence enhancement with protons
when immobilized in a poly(vinylchloride)
matrix, provided that 2-nitrophenyloctyl
ether plasticizer and potassium
tetrakis(4-chlorophenyl)borate additive
are present to prevent dye crystallization
and to facilitate proton diffusion
into the membrane, respectively.

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OBJECTIVE: To study the effect of myopia and spectacle wear on bicycle-related injuries in rural Chinese students. Myopia is common among Chinese students but few studies have examined its effect on daily activities. METHODS: Data on visual acuity, refractive error, current spectacle wear, and history of bicycle use and accidents during the past 3 years were sought from 1891 students undergoing eye examinations in rural Guangdong province. RESULTS: Refractive and accident data were available for 1539 participants (81.3%), among whom the mean age was 14.6 years, 52.5% were girls, 26.8% wore glasses, and 12.9% had myopia of less than -4 diopters in both eyes. More than 90% relied on bicycles to get to school daily. A total of 2931 accidents were reported by 423 participants, with 68 requiring medical attention. Male sex (odds ratio, 1.55; P < .001) and spectacle wear (odds ratio, 1.38; P = .04) were associated with a higher risk of accident, but habitual visual acuity and myopia were unassociated with the crash risk, after adjusting for age, sex, time spent riding, and risky riding behaviors. CONCLUSION: These results may be consistent with data on motor vehicle accidents implicating peripheral vision (potentially compromised by spectacle wear) more strongly than central visual acuity in mediating crash risk.

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Despite an abundance of studies on hybridization and hybrid forms of organizing, scholarly work has failed to distinguish consistently between specific types of hybridity. As a consequence, the analytical category has become blurred and lacks conceptual clarity. Our paper discusses hybridity as the simultaneous appearance of institutional logics in organizational contexts, and differentiates the parallel co-existence of logics from transitional combinations (eventually leading to the replacement of a logic) and more robust combinations in the form of layering and blending. While blending refers to hybridity as an ‘amalgamate’ with original components that are no longer discernible, the notion of layering conceptualizes hybridity in a way that the various elements, or clusters thereof, are added on top of, or alongside, each other, similar to sediment layers in geology. We illustrate and substantiate such conceptual differentiation with an empirical study of the dynamics of public sector reform. In more detail, we examine the parliamentary discourse around two major reforms of the Austrian Federal Budget Law in 1986 and in 2007/2009 in order to trace administrative (reform) paradigms. Each of the three identified paradigms manifests a specific field-level logic with implications for the state and its administration: bureaucracy in Weberian-style Public Administration, market-capitalism in New Public Management, and democracy in New Public Governance. We find no indication of a parallel co-existence or transitional combination of logics, but hybridity in the form of robust combinations. We explore how new ideas fundamentally build on – and are made resonant with – the central bureaucratic logic in a way that suggests layering rather than blending. The conceptual findings presented in our article have implications for the literature on institutional analysis and institutional hybridity.

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The basics of laser driven neutron sources, properties and possible applications are discussed. We describe the laser driven nuclear processes which trigger neutron generation, namely, nuclear reactions induced by laser driven ion beam (ion n), thermonuclear fusion by implosion and photo-induced nuclear (gamma n) reactions. Based on their main properties, i.e. point source (< 100 μm) and short durations (< ns), different applications are described, such as radiography, time-resolved spectroscopy and pump-probe experiments. Prospects on the development of laser technology suggest that, as higher intensities and higher repetition rate lasers become available (for example, using DPSSL technology), laser driven methodologies may provide neutron fluxes comparable to that achieved by accelerator driven neutron sources in the near future.

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Da existência de instituições de ensino superior (IES) nas cidades e nas regiões decorrem efeitos variados que influenciam as dinâmicas sociais e económicas locais. Entre os efeitos mais significativos, e duradoiros, que resultam desta presença, destaca- se a possibilidade de melhorar a qualificação dos recursos humanos. Está demonstrado que territórios com populações mais qualificadas são mais desenvolvidos e, por isso, registam melhores níveis de qualidade de vida. Desta forma, a localização de IES pode ser mais relevante em territórios com níveis de desenvolvimento mais débeis, posicionando-se, nestes casos, como factor de promoção do desenvolvimento. Neste trabalho, que analisa de forma genérica o caso português, e o Alentejo em particular, procuramos avaliar a correlação entre a existência de IES num território e os respectivos níveis de desenvolvimento e qualidade de vida, de modo a consubstanciar o papel das IES enquanto instrumentos de coesão territorial.

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Educação e Formação de Adultos no Alentejo: o Processo de Reconhecimento, Validação e Certificação de Competências (RVCC), no período 2000-2005 pretende ser um contributo para a avaliação dos resultados do Processo de Reconhecimento, Validação e Certificação de Competências (RVCC) concretizado no Alentejo, entre 2000 e 2005, na perspectiva dos adultos que o protagonizaram. No período e território considerados, 2969 pessoas adultas concluíram, com êxito, os seus percursos de qualificação, no âmbito do Processo de RVCC, nas seis instituições que, então, o disponibilizavam: ESDIME – Agência para o Desenvolvimento Local no Alentejo Sudoeste, Fundação Alentejo, ADL – Associação de Desenvolvimento do Litoral Alentejano, Instituto do Emprego e Formação Profissional/Centro de Formação Profissional de Portalegre, Rota do Guadiana – Associação de Desenvolvimento Integrado e Terras Dentro – Associação para o Desenvolvimento Integrado.