995 resultados para Heterogeneous class
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This 24-chapter edited collection will be the first major study of the history of Irish working-class writing.
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Aims. We investigated the response of the solar atmosphere to non-thermal electron beam heating using the radiative transfer and hydrodynamics modelling code RADYN. The temporal evolution of the parameters that describe the non-thermal electron energy distribution were derived from hard X-ray observations of a particular flare, and we compared the modelled and observed parameters.
Methods. The evolution of the non-thermal electron beam parameters during the X1.5 solar flare on 2011 March 9 were obtained from analysis of RHESSI X-ray spectra. The RADYN flare model was allowed to evolve for 110 s, after which the electron beam heating was ended, and was then allowed to continue evolving for a further 300 s. The modelled flare parameters were compared to the observed parameters determined from extreme-ultraviolet spectroscopy.
Results. The model produced a hotter and denser flare loop than that observed and also cooled more rapidly, suggesting that additional energy input in the decay phase of the flare is required. In the explosive evaporation phase a region of high-density cool material propagated upward through the corona. This material underwent a rapid increase in temperature as it was unable to radiate away all of the energy deposited across it by the non-thermal electron beam and via thermal conduction. A narrow and high-density (ne ≤ 1015 cm-3) region at the base of the flare transition region was the source of optical line emission in the model atmosphere. The collision-stopping depth of electrons was calculated throughout the evolution of the flare, and it was found that the compression of the lower atmosphere may permit electrons to penetrate farther into a flaring atmosphere compared to a quiet Sun atmosphere.
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Diagnostic test sensitivity and specificity are probabilistic estimates with far reaching implications for disease control, management and genetic studies. In the absence of 'gold standard' tests, traditional Bayesian latent class models may be used to assess diagnostic test accuracies through the comparison of two or more tests performed on the same groups of individuals. The aim of this study was to extend such models to estimate diagnostic test parameters and true cohort-specific prevalence, using disease surveillance data. The traditional Hui-Walter latent class methodology was extended to allow for features seen in such data, including (i) unrecorded data (i.e. data for a second test available only on a subset of the sampled population) and (ii) cohort-specific sensitivities and specificities. The model was applied with and without the modelling of conditional dependence between tests. The utility of the extended model was demonstrated through application to bovine tuberculosis surveillance data from Northern and the Republic of Ireland. Simulation coupled with re-sampling techniques, demonstrated that the extended model has good predictive power to estimate the diagnostic parameters and true herd-level prevalence from surveillance data. Our methodology can aid in the interpretation of disease surveillance data, and the results can potentially refine disease control strategies.
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Liquid coordination complexes (LCCs) are a new class of liquid Lewis acids, prepared by combining an excess of a metal halide (e.g. GaCl3) with a basic donor molecule (e.g. amides, amines or phosphines). LCCs were used to catalyse oligomerisation of 1-decene to polyalphaolefins (PAOs). Molecular weight distribution and physical properties of the produced oils were compliant with those required for low viscosity synthetic (Group IV) lubricant base oils. Kinematic viscosities at 100 °C of ca. 4 or 6 cSt were obtained, along with viscosity indexes above 120 and pour points below −57 °C. In industry, to achieve similar properties, BF3 gas is used as a catalyst. LCCs are proposed as a safer and economically attractive alternative to BF3 gas for the production of polyalphaolefins.
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Some members of a series of novel pyrrolo-1,5-benzoxazepines (PBOXs) potently induce apoptosis in a number of human cancerous cell lines including HL-60 cells and the drug-resistant chronic myelogenous leukaemia cell line, K562. The apoptotic induction seems to be independent of the mitochondrial peripheral-type benzodiazepine receptor (PBR), which binds these PBOXs with high affinity, due to a lack of correlation between their affinities for the receptor and their apoptotic potencies and their high apoptotic activity in PBR-deficient cells. PBOX-6, a potent member of the series, induces a transient activation of c-Jun N-terminal kinase (JNK) in a dose-dependent manner, which correlates with induction of apoptosis. Expression of a cytoplasmic inhibitor of the JNK signal transduction pathway, Jip-1, prevents JNK activity and significantly reduces the extent of apoptosis induced by PBOX-6. This demonstrates the requirement for JNK in the cellular response to this apoptotic agent. In addition, PBOX-6 activates caspase-3-like proteases in K562 and HL-60 cells. The caspase-3 inhibitor, Z-Asp-Glu-Val-Asp-fluoromethylketone (z-DEVD-fmk), blocks caspase-3-like protease activity in both cell types but only prevents PBOX-6-induced apoptosis in HL-60 cells, suggesting that the requirement for caspase-3-like proteases in the apoptotic pathway is dependent on the cell type.
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This paper provides a comparative analysis of working class consumer credit in Britain and France from the early twentieth century through to the 1980s. It indicates a number of similarities between the two nations in the earlier part of the period: in particular, in the operation of doorstep credit systems. For the British case study, we explore consumer finance offered by credit drapers (sometimes known as tallymen) whilst in France the paper explores a similar system that functioned in the coalmining communities around the city of Lens. Both methods operated on highly socialised relationships that established the trust on which credit was offered and long-term creditor/borrower relationships established. In the second part of the paper, we analyse the different trajectories taken in post-war France and Britain in this area of working class credit. In France this form of socialized credit gradually dwindled due to factors such as ‘Bancarisation’, which saw the major banks emerge as modern bureaucratized providers of credit for workers and their families. In contrast, in Britain the tallymen (and other related forms of doorstep credit providers) were offered a new lease of life in the 1960s and 1970s. This was a period during which British credit providers utilised multiple methods to evade the hire purchase controls put in place by post-war governments. Thus, whilst the British experience was one of fragmented consumer loan types (including the continuation of doorstep credit), the French experience (like elsewhere in Europe) was one of greater consolidation. The paper concludes by reflecting on the role of these developments in the creation of differential experiences of credit inclusion/exclusion in the two nations and the impact of this on financial inequality.
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Heterogeneous catalysis is of great importance both industrially and academically. Rational design of heterogeneous catalysts is highly desirable, and the computational screening and design method is one of the most promising approaches for rational design of heterogeneous catalysts. Herein, we review some attempts towards the rational catalyst design using density functional theory from our group. Some general relationships and theories on the activity and selectivity are covered, such as the Brønsted–Evans–Polanyi relation, volcano curves/surfaces, chemical potentials, optimal adsorption energy window and energy descriptor of selectivity. Furthermore, the relations of these relationships and theories to the rational design are discussed, and some examples of computational screening and design method are given.
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In 1748, Bartholomew Mosse, a curious combination of surgeon, obstetrician and entertainment impresario, established a pleasure garden on the northern fringes of Dublin. Ostensibly designed to fund the construction of a maternity hospital to be located adjacently, Mosse’s New Pleasure Gardens became one of the premier leisure resorts in Dublin. This was to have a profound effect on the city’s urban form. Within a few years the gardens became an epicentre of speculative development as the upper classes jostled to build their houses in the vicinity. Meanwhile, the creation nearby of Sackville Mall, a wide and generous strolling ground, established a whole section of the city dedicated to haute spectacle, display and leisure. Like other pleasure gardens in the British Isles, Mosse’s venture introduced new, commodified forms of entertainment. In the colonial context of eighteenth-century Ireland, however, ‘a land only recently won and insecurely held’ (Foster, 1988) by the Protestant Anglo-Irish settler class, the production of culture and spectacle was perhaps more significant than elsewhere. Indeed, the form of Mosse’s gardens echoed the private city gardens of a key figure in the Anglo-Irish aristocracy, while the hospital itself was constructed in a style of a Palladian country house, symbol of colonial presence in the countryside. However, like other pleasure gardens, the mix of music and alcohol, the heterogeneous crowd culled from across social and gender boundaries, and a landscape punctuated with secluded corners, meant that it also acquired a dubious reputation as a haunt of louche and illicit behaviours. The curious juxtaposition between a maternity hospital and pleasure garden, therefore, begins to assume other, hitherto hidden complexities. These are borne out by a closer examination of the architecture of the hospital, the shape of its landscape and the records of its patrons and patients.