163 research outputs found

    Evaluating the role of media in fostering political engagement among young people in the UK: a comparative analysis of social and legacy media coverage of political events and contribution to feelings of political empowerment

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    The following thesis examines the impact of social and legacy media on young people’s political engagement as well as on their attitudes to, feelings towards and beliefs about politics. This was accomplished using a three-tiered design which integrated both quantitative and qualitative techniques. The aim of this design was to ensure that young people were afforded a voice in the ongoing debate around youth apathy. To this end, a direct comparison of social and legacy media coverage of various case studies was undertaken. This initial comparison was accompanied by a series of interviews using Interpretative Phenomenological Analysis (Smith, Flowers & Larkin, 2009). The interviews focused on individual engagement with politics and social and legacy media, in order to get a sense of each individuals understanding of their role in British politics as well as the feelings and attitudes towards media and politics more widely. The three-tiered design concluded with a quantitative questionnaire assessing governmental trust, political efficacy, self-efficacy, and self-esteem by way of a series of standardised measures. From this mixed-methods approach, two main findings arise. Firstly, that social media such as Twitter hold the potential to facilitate political engagement in young people, beyond what is currently achieved by the British legacy media. The second finding suggests that there has been fundamental paradigmatic shift of youth conceptions of politics from what could be considered traditional political behaviours (such as voting and party membership; StrĂžmsnes, 2009) to lifestyle orientated choices (such as boy/buycotts; Copeland, 2014; Gil de ZĂșñiga, Copeland & Bimber, 2014), mediated by social media. Overall the results of the thesis foster a dualistic understanding of British young people who are simultaneously engaged with and apathetic toward “politics” dependant on how the term is defined

    The biology and ecology of the swede midge Contarinia nasturii (Kieffer) (Diptera; Cecidomyidae).

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    PhD ThesisThe swede midge Contarinia nasturtii (Kieffer), a member of the family Cecidomyidae (Order, Diptera), is a small insect, the larvae of which induce gall formation on numerous cruciferous plants. Kieffer (1888) first described the midge which he reared from larvae occupying the closed flowers of Nasturtium palustre D. C., now known to be Rorippa islandica (Oeder) Borbas. In subsequent years numerous authors have reported the midge, under various synonyms, as a frequent pest of several important cruciferous crops. Briefly this thesis re-examines the life-cycle of the swede midge in detail and investigates the effect of what seem to be the important environmental factors on successive stages of development. After consideration of the observed population fluctuations of C. nasturtii at Nafferton, Northumberland, during 1957-1960, the thesis concludes with a discussion of population change in relation to various components of the environment.Agricultural Research Council

    On the incorporation of conservation laws in machine learning tabulation of kinetics for reacting flow simulation

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    Tabulation of chemical mechanisms with artificial neural networks (ANNs) offers significant speed benefits when computing the real-time integration of reaction source terms in turbulent reacting flow simulations. In such approaches, the ANNs should be physically consistent with the reaction mechanism by conserving mass and chemical elements, as well as obey the bounds of species mass fractions. In the present paper, a method is developed for satisfying these constraints to machine precision. The method can be readily applied to any reacting system and appended to the existing ANN architectures. To satisfy the conservation laws, certain species in a reaction mechanism are selected as residual species and recalculated after ANN predictions of all of the species have been made. Predicted species mass fractions are set to be bounded. While the residual species mass fractions are not guaranteed to be non-negative, it is shown that negative predictions can be avoided in almost all cases and easily rectified if necessary. The ANN method with conservation is applied to one-dimensional laminar premixed flame simulations, and comparisons are made with simulations performed with direct integration (DI) of chemical kinetics. The ANNs with conservation are shown to satisfy the conservation laws for every reacting point to machine precision and, furthermore, to provide results in better agreement with DI than ANNs without conservation. It is, thus, shown that the proposed method reduces accumulation of errors and positively impacts the overall accuracy of the ANN prediction at negligible additional computational cost

    Heterologous production of the insecticidal pea seed albumin PA1 protein by Pichia pastoris and protein engineering to potentiate aphicidal activity via fusion to snowdrop lectin Galanthus nivalis agglutinin; GNA)

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    BackgroundNew bioinsecticides with novel modes of action are urgently needed to minimise the environmental and safety hazards associated with the use of synthetic chemical pesticides and to combat growing levels of pesticide resistance. The pea seed albumin PA1b knottin peptide is the only known proteinaceous inhibitor of insect vacuolar adenosine triphosphatase (V-ATPase) rotary proton pumps. Oral toxicity towards insect pests and an absence of activity towards mammals makes Pa1b an attractive candidate for development as a bioinsecticide. The purpose of this study was to investigate if Pichia pastoris could be used to express a functional PA1b peptide and if it’s insecticidal activity could be enhanced via engineering to produce a fusion protein comprising the pea albumin protein fused to the mannose-specific snowdrop lectin (Galanthus nivalis agglutinin; GNA).ResultsWe report the production of a recombinant full-length pea albumin protein (designated PAF) and a fusion protein (PAF/GNA) comprised of PAF fused to the N-terminus of GNA in the yeast Pichia pastoris. PAF was orally toxic to pea (Acyrthosiphon pisum) and peach potato (Myzus persicae) aphids with respective, Day 5 LC50 values of 54 ”M and 105 ”M derived from dose–response assays. PAF/GNA was significantly more orally toxic as compared to PAF, with LC50 values tenfold (5 ”M) and 3.3-fold (32 ”M) lower for pea and peach potato aphids, respectively. By contrast, no phenotypic effects were observed for worker bumble bees (Bombus terristrus) fed PAF, GNA or PAF/GNA in acute toxicity assays. Confocal microscopy of pea aphid guts after pulse-chase feeding fluorescently labelled proteins provides evidence that enhanced efficacy of the fusion protein is attributable to localisation and retention of PAF/GNA to the gut epithelium. In contact assays the fusion protein was also found to be significantly more toxic towards A. pisum as compared to PAF, GNA or a combination of the two proteins.ConclusionsOur results suggest that GNA mediated binding to V-type ATPase pumps acts to potentiate the oral and contact aphicidal activity of PAF. This work highlights potential for the future commercial development of plant protein-based bioinsecticides that offer enhanced target specificity as compared to chemical pesticides, and compatibility with integrated pest management strategies

    Engineering sustainable shorelines: an evaluation framework

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    Over the past century, many of the shorelines in the Salish Sea have undergone a transformation from natural to armoured. In response, there is now a significant push to use soft solutions, such as gravel beaches and vegetation, to try to mitigate effects on the natural environment. While in many areas soft solutions are entirely appropriate, in others they do not provide adequate protection from erosion or flooding. This presentation explores the idea that a one-size-fits-all solution is insufficient, and outlines a novel evaluation framework to assess the feasibility of shoreline protection works using 11 environmental and engineering performance indicators. SNC-Lavalin Inc developed an Engineering and Environmental Evaluation Framework for the Town of Qualicum Beach, BC, to assess the feasibility of shoreline protection works proposed for the Town’s waterfront. The Framework assesses the relative feasibility and impact of shoreline protection alternatives (or options), recognizing that there may only be a ‘best’ option and not necessarily a ‘right’ option in some cases. Each shoreline protection alternative is evaluated based on the same set of 11 criteria, which identify option- and site-specific relationships with the expected coastal/marine conditions, foreshore ecological services, and efficacy of investment. We will outline the Framework basis and criteria, and present two real-world examples of how it was applied to waterfront projects in Qualicum Beach. The first project is a low-lying property with a natural shoreline that was undergoing significant erosion. The second project is located along a portion of the Town’s waterfront walkway, where upgrades to the adjacent roadway and estuary are underway. The examples illustrate the importance of considering multi-faceted performance indicators to determine the best option for a shoreline, whether that be a beach fill or a seawall

    Compliance of smokeless tobacco supply chain actors and products with tobacco control laws in Bangladesh, India and Pakistan: Protocol for a multicentre sequential mixed-methods study

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    Introduction: South Asia is home to more than 300 million smokeless tobacco (ST) users. Bangladesh, India and Pakistan as signatories to the Framework Convention for Tobacco Control (FCTC) have developed policies aimed at curbing the use of tobacco. The objective of this study is to assess the compliance of ST point-of-sale (POS) vendors and the supply chain with the articles of the FCTC and specifically with national tobacco control laws. We also aim to assess disparities in compliance with tobacco control laws between ST and smoked tobacco products.Methods and analysis: The study will be carried out at two sites each in Bangladesh, India and Pakistan. We will conduct a sequential mixed-methods study with five components: (1) mapping of ST POS, (2) analyses of ST samples packaging, (3) observation, (4) survey interviews of POS and (5) in-depth interviews with wholesale dealers/suppliers/manufacturers of ST. We aim to conduct at least 300 POS survey interviews and observations, and 6-10 in-depth interviews in each of the three countries. Data collection will be done by trained data collectors. The main statistical analysis will report the frequencies and proportions of shops that comply with the FCTC and local tobacco control policies, and provide a 95% CI of these estimates. The qualitative in-depth interview data will be analysed using the framework approach. The findings will be connected, each component informing the focus and/or design of the next component.Ethics and dissemination: Ethical approvals for the study have been received from the Health Sciences Research Governance Committee at the University of York, UK. In-country approvals were taken from the National Bioethics Committee in Pakistan, the Bangladesh Medical Research Council and the Indian Medical Research Council. Our results will be disseminated via scientific conferences, peer-reviewed research publications and press releases

    Spider venom neurotoxin based bioinsecticides: A novel bioactive for the control of the Asian citrus psyllid Diaphorina citri (Hemiptera)

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    The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a key vector of the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas) associated with huanglongbing (HLB), the most serious and currently incurable disease of citrus worldwide. Here we report the first investigation into the potential use of a spider venom-derived recombinant neurotoxin, ω/Îș-HxTx-Hv1h (hereafter HxTx-Hv1h) when delivered alone or when fused to snowdrop lectin (Galanthus nivalis agglutinin; GNA) to control D. citri. Proteins, including GNA alone, were purified from fermented transformed yeast Pichia pastoris cultures. Recombinant HxTx-Hv1h, HxTx-Hv1h/GNA and GNA were all orally toxic to D. citri, with Day 5 median lethal concentrations (LC 50) derived from dose-response artificial diet assays of 27, 20 and 52 ÎŒM, respectively. Western analysis of whole insect protein extracts confirmed that psyllid mortality was attributable to protein ingestion and that the fusion protein was stable to cleavage by D. citri proteases. When applied topically (either via droplet or spray) HxTx-Hv1h/GNA was the most effective of the proteins causing >70 % mortality 5 days post treatment, some 2 to 3-fold higher levels of mortality as compared to the toxin alone. By contrast, no significant mortality or phenotypic effects were observed for bumble bees (Bombus terrestris L.) fed on the recombinant proteins in acute toxicity assays. This suggests that HxTx-Hv1h/GNA has potential as a novel bioinsecticide for the management of D. citri offering both enhanced target specificity as compared to chemical pesticides and compatibility with integrated pest management (IPM) strategies

    The UK's Global Health Respiratory Network: Improving respiratory health of the world's poorest through research collaborations.

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    Respiratory disorders are responsible for considerable morbidity, health care utilisation, societal costs and approximately one in five deaths worldwide [1-4]. Yet, despite this substantial health and societal burden – which particularly affects the world’s poorest populations and as such is a major contributor to global health inequalities – respiratory disorders have historically not received the policy priority they warrant. For example, despite causing an estimated 1000 deaths per day, less than half of the world’s countries collect data on asthma prevalence (http://www.globalasthmareport.org/). This is true for both communicable and non-communicable respiratory disorders, many of which are either amenable to treatment or preventable
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