622 research outputs found

    The Fuchs factor: Espionage, the Soviet atomic bomb and Anglo-American relations

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    oai:repository.canterbury.ac.uk:96z70Klaus Fuchs, born in 1911, was a communist and theoretical physicist. The Manhattan Project was infiltrated by a quiet, treacherous man who appeared loyal to his country. Fuchs also headed the British atomic bomb project at Harwell from 1946 until his arrest in 1949. The impact of Fuchs in theoretical physics, the atomic bombs of America, the Soviet Union and Britain is unprecedented. The impact of the Bomb did not just inject fear into Western allies and civilians of both the Soviet Union and America; it also resonated through popular culture, architecture, and the technological race which endeavoured space travel. This thesis examines Fuchs’s role in the Soviet atomic bomb project that conceived of Joe-1. Although Fuchs’s treason is at the epicentre of its analysis, the thesis peripherally considers the successes of the FBI and MI5, and whether their security apparatuses were efficient in catching Fuchs. It also scrutinises Fuchs’s impact on Anglo-American relations and post-war foreign policy. Other spy cases in the early Cold War are addressed, and their overall impact on Anglo-American atomic relations considered. The thesis concludes with a consideration of Fuchs’s impact on intelligence relations between the American and British establishments

    Believing is achieving: a longitudinal study of self-efficacy and positive affect in resettled refugees

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    Research has shown that self-efficacy can play an important role in recovery from trauma (Benight and Bandura 2004). We hypothesised that for refugees, whose (often traumatic) experiences pre- and post-resettlement have been linked to a decrease in their wellbeing (e.g., Aspinall and Watters 2010), self-efficacy would play a key role in improving wellbeing. This paper investigates the link between self-efficacy and positive affect among resettled refugees (N = 180). Research used mixed methods. The longitudinal survey with three time points confirmed that higher levels of general self-efficacy were consistently associated with better positive affect at later time points. The reverse effects, from positive affect to later self-efficacy, were not significant. In addition, qualitative interviews with a subsample provide suggestions as to how self-efficacy of refugees might be improved: that is, by improving access to employment and language classes, by clarifying how British social and cultural systems work, including the practical information necessary to navigate daily life, and by providing more opportunities to increase social networks, all suggesting the necessity of a proactive role of the receiving society

    ‘Howling at the scrabble-board’: Exploring classroom literature from an autistic viewpoint

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    There has, to date, been little discussion of how autism may affect the experience of the reading of fiction for pupils in the classroom, other than through a deficit model. One of the researchers in this study (‘Celia’) is training to be a secondary school English teacher and identifies as autistic. Her experience provides an enriched understanding of the subject and enables the study to be undertaken in line with best practice for autism research. Her experiences are explored within the concepts of Theory of Mind, empathic regulation, language awareness and local rather than global processing bias. Impact on managing authentic engagement with texts for all pupils is discussed, together with specific questions for teachers regarding appropriate support for – and celebration of – autistic pupils’ reactions to fiction

    Tin-containing zeolites are highly active catalysts for the isomerization of glucose in water

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    The isomerization of glucose into fructose is a large-scale reaction for the production of high-fructose corn syrup (HFCS; reaction performed by enzyme catalysts) and recently is being considered as an intermediate step in the possible route of biomass to fuels and chemicals. Here, it is shown that a large-pore zeolite that contains tin (Sn-Beta) is able to isomerize glucose to fructose in aqueous media with high activity and selectivity. Specifically, a 10% (wt/wt) glucose solution containing a catalytic amount of Sn-Beta (1∶50 Sn:glucose molar ratio) gives product yields of approximately 46% (wt/wt) glucose, 31% (wt/wt) fructose, and 9% (wt/wt) mannose after 30 min and 12 min of reaction at 383 K and 413 K, respectively. This reactivity is achieved also when a 45 wt% glucose solution is used. The properties of the large-pore zeolite greatly influence the reaction behavior because the reaction does not proceed with a medium-pore zeolite, and the isomerization activity is considerably lower when the metal centers are incorporated in ordered mesoporous silica (MCM-41). The Sn-Beta catalyst can be used for multiple cycles, and the reaction stops when the solid is removed, clearly indicating that the catalysis is occurring heterogeneously. Most importantly, the Sn-Beta catalyst is able to perform the isomerization reaction in highly acidic, aqueous environments with equivalent activity and product distribution as in media without added acid. This enables Sn-Beta to couple isomerizations with other acid-catalyzed reactions, including hydrolysis/isomerization or isomerization/dehydration reaction sequences [starch to fructose and glucose to 5-hydroxymethylfurfural (HMF) demonstrated here]

    How Does Treatment Coverage and Proportion Never Treated Influence the Success of Schistosoma mansoni Elimination as a Public Health Problem by 2030?

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    Background: The 2030 target for schistosomiasis is elimination as a public health problem (EPHP), achieved when the prevalence of heavy-intensity infection among school-Aged children (SAC) reduces to &lt;1%. To achieve this, the new World Health Organization guidelines recommend a broader target of population to include pre-SAC and adults. However, the probability of achieving EPHP should be expected to depend on patterns in repeated uptake of mass drug administration by individuals. Methods: We employed 2 individual-based stochastic models to evaluate the impact of school-based and community-wide treatment and calculated the number of rounds required to achieve EPHP for Schistosoma mansoni by considering various levels of the population never treated (NT). We also considered 2 age-intensity profiles, corresponding to a low and high burden of infection in adults. Results: The number of rounds needed to achieve this target depends on the baseline prevalence and the coverage used. For low-and moderate-Transmission areas, EPHP can be achieved within 7 years if NT ≤10% and NT &lt;5%, respectively. In high-Transmission areas, community-wide treatment with NT &lt;1% is required to achieve EPHP. Conclusions: The higher the intensity of transmission, and the lower the treatment coverage, the lower the acceptable value of NT becomes. Using more efficacious treatment regimens would permit NT values to be marginally higher. A balance between target treatment coverage and NT values may be an adequate treatment strategy depending on the epidemiological setting, but striving to increase coverage and/or minimize NT can shorten program duration.</p

    Postmetamorphic ontogenetic allometry and the evolution of skull shape in Nest-building frogs Leptodactylus (Anura: Leptodactylidae)

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    Allometry constitutes an important source of morphological variation. However, its influence in head development in anurans has been poorly explored. By using geometric morphometrics followed by statistical and comparative methods we analyzed patterns of allometric change during cranial postmetamorphic ontogeny in species of Nest-building frogs Leptodactylus (Leptodactylidae). We found that the anuran skull is not a static structure, and allometry plays an important role in defining its shape in this group. Similar to other groups with biphasic life-cycle, and following a general trend in vertebrates, ontogenetic changes mostly involve rearrangement in rostral, otoccipital, and suspensorium regions. Ontogenetic transformations are paralleled by shape changes associated with evolutionary change in size, such that the skulls of species of different intrageneric groups are scaled to each other, and small and large species show patterns of paedomorphic/peramorphic features, respectively. Allometric trajectories producing those phenotypes are highly evolvable though, with shape change direction and magnitude varying widely among clades, and irrespective of changes in absolute body size. These results reinforce the importance of large-scale comparisons of growth patterns to understand the plasticity, evolution, and polarity of morphological changes in different clades.Fil: Duport Bru, Ana Sofía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Ponssa, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Vera Candioti, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin
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