84 resultados para island exploration
Resumo:
Within the development discourse, the narratives of the poor are a well utilized rhetorical tool to describe poverty and its causes. However, narratives can also reveal the beliefs and ‘world-view’ of the narrators. To explore this influence, the authors applied a discursive approach, to deconstruct the narratives of 101 slum dwellers in Kibera, Nairobi. The results revealed that poverty was largely attributed to external constraints, beyond an individual's control. Despite wanting a better life, participants held low expectations for the future. Hopes and dreams were placed on their children. While risk and uncertainty was a constant theme, large differences were found between genders as to the aspirations for the future. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Resumo:
The study explores the uptake of livestock vaccination among poor farming communities in Tamil Nadu State, India by revisiting innovation diffusion theory. Overall, 601 farmers participated in the study. We found the adoption of particular vaccines was strongly influenced by socio-cultural grouping i.e. caste, rather than other factors such as income, age, education-level or gender. Adoption was also related to specific knowledge frames regarding disease causality, rather than any wider ethno-veterinary beliefs. Thus, the adoption of livestock vaccination is unlikely to improve without knowledge transfer activities, which acknowledge both social divisions and local epistemologies regarding animal health. Copyright © 2010 John Wiley & Sons, Ltd.
Resumo:
P>Type III secretion (T3S) plays a pivotal role in the colonization of ruminant hosts by Enterohemorrhagic Escherichia coli (EHEC). The T3S system translocates effector proteins into host cells to promote bacterial attachment and persistence. The repertoire and variation in prophage regions underpins differences in the pathogenesis and epidemiology of EHEC strains. In this study, we have used a collection of deletions in cryptic prophages and EHEC O157 O-islands to screen for novel regulators of T3S. Using this approach we have identified a family of homologous AraC-like regulators that indirectly repress T3S. These prophage-encoded secretion regulator genes (psr) are found exclusively on prophages and are associated with effector loci and the T3S activating Pch family of regulators. Transcriptional profiling, mutagenesis and DNA binding studies were used to show that these regulators usurp the conserved GAD acid stress resistance system to regulate T3S by increasing the expression of GadE (YhiE) and YhiF and that this regulation follows attachment to bovine epithelial cells. We further demonstrate that PsrA and effectors encoded within cryptic prophage CP933-N are required for persistence in a ruminant model of colonization.
The island and the world: kinship, friendship and living together in selected writings of Sam Selvon
Resumo:
This article argues that the ethical force of Trinidadian Sam Selvon’s creative writings comes from the particular configuration of living together that he is interested in, both in his Trinidadian novels and his London ones. It reads examples of this living together alongside and in difference that emerges through his focus on the relations between neighbours, friends and lovers, rather than the kinship relations of family. It argues that his works thereby map horizontal zones of attachment and possible solidarities across groupings that reconfigure vertically inscribed genealogical paradigms of belonging to place and each other based on models of historical continuity and inheritance.
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In this study two new measures of lexical diversity are tested for the first time on French. The usefulness of these measures, MTLD (McCarthy and Jarvis (2010 and this volume) ) and HD-D (McCarthy and Jarvis 2007), in predicting different aspects of language proficiency is assessed and compared with D (Malvern and Richards 1997; Malvern, Richards, Chipere and Durán 2004) and Maas (1972) in analyses of stories told by two groups of learners (n=41) of two different proficiency levels and one group of native speakers of French (n=23). The importance of careful lemmatization in studies of lexical diversity which involve highly inflected languages is also demonstrated. The paper shows that the measures of lexical diversity under study are valid proxies for language ability in that they explain up to 62 percent of the variance in French C-test scores, and up to 33 percent of the variance in a measure of complexity. The paper also provides evidence that dependence on segment size continues to be a problem for the measures of lexical diversity discussed in this paper. The paper concludes that limiting the range of text lengths or even keeping text length constant is the safest option in analysing lexical diversity.
Resumo:
The nature of private commercial real estate markets presents difficulties for monitoring market performance. Assets are heterogeneous and spatially dispersed, trading is infrequent and there is no central marketplace in which prices and cash flows of properties can be easily observed. Appraisal based indices represent one response to these issues. However, these have been criticised on a number of grounds: that they may understate volatility, lag turning points and be affected by client influence issues. Thus, this paper reports econometrically derived transaction based indices of the UK commercial real estate market using Investment Property Databank (IPD) data, comparing them with published appraisal based indices. The method is similar to that presented by Fisher, Geltner, and Pollakowski (2007) and used by Massachusett, Institute of Technology (MIT) on National Council of Real Estate Investment Fiduciaries (NCREIF) data, although it employs value rather than equal weighting. The results show stronger growth from the transaction based indices in the run up to the peak in the UK market in 2007. They also show that returns from these series are more volatile and less autocorrelated than their appraisal based counterparts, but, surprisingly, differences in turning points were not found. The conclusion then debates the applications and limitations these series have as measures of market performance.
Resumo:
This article investigates the nature of enterprise pedagogy in music. It presents the results of a research project that applied the practices of enterprise learning developed in the post-compulsory music curriculum in England to the teaching of the National Curriculum for music for 11-to-14-year-olds. In doing so, the article explores the nature of enterprise learning and the nature of pedagogy, in order to consider whether enterprise pedagogy offers an effective way to teach the National Curriculum. Enterprise pedagogy was found to have a positive effect on the motivation of students and on the potential to match learning to the needs of students of different abilities. Crucially, it was found that, to be effective, not only did the teacher’s practice need to be congruent with the beliefs and theories on which it rests, but that the students also needed to share in these underlying assumptions through their learning. The study has implications for the way in which teachers work multiple pedagogies in the process of developing their pedagogical identity.
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BipA is a novel member of the ribosome binding GTPase superfamily and is widely distributed in bacteria and plants. We report here that it regulates -multiple cell surface- and virulence-associated -components in the enteropathogenic Escherichia coli (EPEC) strain E2348/69. The regulated components include bacterial flagella, the espC pathogenicity island and a type III secretion system specified by the locus of enterocyte effacement (LEE). BipA positively regulated the espC and LEE gene clusters through transcriptional control of the LEE-encoded regulator, Ler. Additionally, it affected the pattern of proteolysis of intimin, a key LEE-encoded adhesin specified by the LEE. BipA control of the LEE operated independently of the previously characterized regulators Per, integration host factor and H-NS. In contrast, it negatively regulated the flagella-mediated motility of EPEC and in a Ler-independent manner. Our results indicate that the BipA GTPase functions high up in diverse regulatory cascades to co-ordinate the expression of key pathogenicity islands and other virulence-associated factors in E. coli.
Resumo:
Several bis-malonatooxidovanadium(IV) complexes of the general type [M(2)(H2(O))(n)][VO(mal)(2)(H(2)O)] (where M = Li(1), Na(2), K(3), Cs(4) and NH4(5); n = 3.5, 1, 3, 1 and 1, respectively) were isolated in good yield and high purity. These complexes were fully characterized by various physicochemical techniques (elemental analysis, UV- Vis, IR, EPR, CV, etc.) complexes 1, 2 and 3 were structurally characterized by single crystal X- ray diffraction technique. In vivo antidiabetic properties of bis- malonato complexes 1, 2, 3 and 5 have been studied using Streptozotocin induced diabetic rats. Significant lowering of blood sugar level has been noticed. At the same time these complexes were found to regulate secondary pathophysiological complications like liver damage and lowering of the total antioxidant status (TAS) in diabetic rats. Results of these study are expected to a expand the possibility of designing new oxidovanadium(IV) complexes of O, O chelating ligands with significant antidiabetic properties
Resumo:
Using the eye-movement monitoring technique in two reading comprehension experiments, we investigated the timing of constraints on wh-dependencies (so-called ‘island’ constraints) in native and nonnative sentence processing. Our results show that both native and nonnative speakers of English are sensitive to extraction islands during processing, suggesting that memory storage limitations affect native and nonnative comprehenders in essentially the same way. Furthermore, our results show that the timing of island effects in native compared to nonnative sentence comprehension is affected differently by the type of cue (semantic fit versus filled gaps) signalling whether dependency formation is possible at a potential gap site. Whereas English native speakers showed immediate sensitivity to filled gaps but not to lack of semantic fit, proficient German-speaking learners of L2 English showed the opposite sensitivity pattern. This indicates that initial wh-dependency formation in nonnative processing is based on semantic feature-matching rather than being structurally mediated as in native comprehension.
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Particle filters are fully non-linear data assimilation techniques that aim to represent the probability distribution of the model state given the observations (the posterior) by a number of particles. In high-dimensional geophysical applications the number of particles required by the sequential importance resampling (SIR) particle filter in order to capture the high probability region of the posterior, is too large to make them usable. However particle filters can be formulated using proposal densities, which gives greater freedom in how particles are sampled and allows for a much smaller number of particles. Here a particle filter is presented which uses the proposal density to ensure that all particles end up in the high probability region of the posterior probability density function. This gives rise to the possibility of non-linear data assimilation in large dimensional systems. The particle filter formulation is compared to the optimal proposal density particle filter and the implicit particle filter, both of which also utilise a proposal density. We show that when observations are available every time step, both schemes will be degenerate when the number of independent observations is large, unlike the new scheme. The sensitivity of the new scheme to its parameter values is explored theoretically and demonstrated using the Lorenz (1963) model.
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Version 1 of the Global Charcoal Database is now available for regional fire history reconstructions, data exploration, hypothesis testing, and evaluation of coupled climate–vegetation–fire model simulations. The charcoal database contains over 400 radiocarbon-dated records that document changes in charcoal abundance during the Late Quaternary. The aim of this public database is to stimulate cross-disciplinary research in fire sciences targeted at an increased understanding of the controls and impacts of natural and anthropogenic fire regimes on centennial-to-orbital timescales. We describe here the data standardization techniques for comparing multiple types of sedimentary charcoal records. Version 1 of the Global Charcoal Database has been used to characterize global and regional patterns in fire activity since the last glacial maximum. Recent studies using the charcoal database have explored the relation between climate and fire during periods of rapid climate change, including evidence of fire activity during the Younger Dryas Chronozone, and during the past two millennia.