603 research outputs found

    Genetic Characterization of the Tick-Borne Orbiviruses

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    The International Committee for Taxonomy of Viruses (ICTV) recognizes four species of tick-borne orbiviruses (TBOs): Chenuda virus, Chobar Gorge virus, Wad Medani virus and Great Island virus (genus Orbivirus, family Reoviridae). Nucleotide (nt) and amino acid (aa) sequence comparisons provide a basis for orbivirus detection and classification, however full genome sequence data were only available for the Great Island virus species. We report representative genome-sequences for the three other TBO species (virus isolates: Chenuda virus (CNUV); Chobar Gorge virus (CGV) and Wad Medani virus (WMV)). Phylogenetic comparisons show that TBOs cluster separately from insect-borne orbiviruses (IBOs). CNUV, CGV, WMV and GIV share low level aa/nt identities with other orbiviruses, in 'conserved' Pol, T2 and T13 proteins/genes, identifying them as four distinct virus-species. The TBO genome segment encoding cell attachment, outer capsid protein 1 (OC1), is approximately half the size of the equivalent segment from insect-borne orbiviruses, helping to explain why tick-borne orbiviruses have a ~1 kb smaller genome

    Mars oxygen production system design

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    The design and construction phase is summarized of the Mars oxygen demonstration project. The basic hardware required to produce oxygen from simulated Mars atmosphere was assembled and tested. Some design problems still remain with the sample collection and storage system. In addition, design and development of computer compatible data acquisition and control instrumentation is ongoing

    Canonical Generations and the British Left: The Narrative Construction of the Miners’ Strike 1984–85

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    ‘Generations’ have been invoked to describe a variety of social and cultural relationships, and to understand the development of self-conscious group identity. Equally, the term can be an applied label and politically useful construct; generations can be retrospectively produced. Drawing on the concept of ‘canonical generations’ – those whose experiences come to epitomise an event of historic and symbolic importance – this article examines the narrative creation and functions of ‘generations’ as collective memory shapes and re-shapes the desire for social change. Building a case study of the canonical role of the miners’ strike of 1984–85 in the narrative history of the British left, it examines the selective appropriation and transmission of the past in the development of political consciousness. It foregrounds the autobiographical narratives of activists who, in examining and legitimising their own actions and prospects, (re)produce a ‘generation’ in order to create a relatable and useful historical understanding

    Comparison of bulk milk antibody and youngstock serology screens for determining herd status for Bovine Viral Diarrhoea Virus

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    BACKGROUND: This paper examines the use of Bulk Milk antibody (BM Ab), Youngstock (YS) serology (Check Tests) and Bulk Milk PCR (BM PCR) for determining the presence or absence of animals persistently infected (PI) with Bovine Viral Diarrhoea Virus (BVDV) within a herd. Data is presented from 26 herds where average herd sizes were 343 and 98 animals for dairy and beef units respectively. Seventeen herds had sufficient data to analyse using Receiver Operating Characteristic (ROC) and probability curves enabling calculation of the sensitivity and specificity of BM Ab and YS Check tests for determining the presence of PI animals within herds in this dataset. RESULTS: Using BM Ab to screen a herd for the presence of PI animals, achieved a herd level sensitivity and specificity of 80.00 % (44.39–97.48 %) and 85.71 % (42.13–99.64 %) respectively (95 % confidence intervals quoted). Sensitivity and specificity of YS Check Tests at a cut off of 3/10 Ab positive YS were 81.82 % (48.22–97.72 %) and 66.67 % (22.28–95.67 %) respectively (95 % confidence interval). These results were achieved by comparing the screening tests to whole herd PI searches that took place 1–19 months after the initial screen with a mean interval of 8 months. Removal of this delay by taking BM samples on the day of a whole herd test and simulating a YS Check Test from the herd test data produced improvements in the reliability of the Check Tests. BM Ab sensitivity and specificity remained unchanged. However, the Check Test sensitivity and specificity improved to 90.9 % (58.72–99.77 %) and 100 % (54.07–100 %) respectively (95 % confidence interval) at a cut of off 2.5/10 Ab positive animals. Our limited BM PCR results identified 5/23 dairy farms with a positive BM PCR result; two contained milking PIs, two had non-milking PIs and another had no PIs identified. CONCLUSIONS: Delaying a PI search following an initial herd screen decreased the diagnostic accuracy and relevance of our results. With careful interpretation, longitudinal surveillance using a combination of the techniques discussed can successfully determine farm status and therefore allow changes in BVDV status to be detected early, thus enabling prompt action in the event of a BVDV incursion

    Magnetoroton scattering by phonons in the fractional quantum Hall regime

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    Motivated by recent phonon spectroscopy experiments in the fractional quantum Hall regime we consider processes in which thermally excited magnetoroton excitations are scattered by low energy phonons. We show that such scattering processes can never give rise to dissociation of magnetorotons into unbound charged quasiparticles as had been proposed previously. In addition we show that scattering of magnetorotons to longer wavelengths by phonon absorption is possible because of the shape of the magnetoroton dispersion curve and it is shown that there is a characteristic cross-over temperature above which the rate of energy transfer to the electron gas changes from an exponential (activated) to a power law dependence on the effective phonon temperature.Comment: LaTex document, 3 eps figures. submitted to Phys Rev

    Practitioner accounts and knowledge production: an analysis of three marketing discourses

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    Responding to repeated calls for marketing academicians to connect with marketing actors, we offer an empirically-sourced discourse analysis of the ways in which managers portray their practices. Focusing on the micro-discourses and narratives that marketing actors draw upon to represent their work we argue that dominant representations of marketing knowledge production present a number of critical concerns for marketing theory and marketing education. We also evidence that the often promoted idea of a need to close the gap between theory - as a dominant discourse - and practice, as a way of doing marketing, is problematic to pursue. We suggest that a more fruitful agenda resides in the development of a range of polyphonic and creative micro-discourses of management, promoting context, difference and individual meaning in marketing knowledge production

    Prime beef cuts : culinary images for thinking 'men'

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    The paper contributes to scholarship theorising the sociality of the brand in terms of subject positions it makes possible through drawing upon the generative context of circulating discourses, in this case of masculinity, cuisine and celebrity. Specifically, it discusses masculinity as a socially constructed gender practice (Bristor and Fischer, 1993), examining materialisations of such practice in the form of visualisations of social relations as resources for 'thinking gender' or 'doing gender'. The transformative potential of the visualisations is illuminated by exploring the narrative content choreographed within a series of photographic images positioning the market appeal of a celebrity chef through the medium of a contemporary lifestyle cookery book. We consider how images of men 'doing masculinity'are not only channelled into reproducing existing gender hierarchy and compulsory heterosexuality in the service of commercial ends, but also into disrupting such enduring stereotyping through subtle reframing. We acknowledge that masculinity is already inscribed within conventionalised representations of culinary culture. In this case we consider how traces of masculinity are exploited and reinscribed through contemporary images that generate resources for rethinking masculine roles and identities, especially when viewed through the lens of stereotypically feminised pursuits such as shopping, food preparation, cooking, and the communal intimacy of food sharing. We identify unsettling tensions within the compositions, arguing that they relate to discursive spaces between the gendered positions written into the images and the popular imagination they feed off. Set against landscapes of culinary culture, we argue that the images invoke a brand of naively roughish "laddishness" or "blokishness", rendering it in domesticated form not only as benign and containable, but fashionable, pliable and, importantly, desirable. We conclude that although the images draw on stereotypical premeditated notions of a feral, boisterous and untamed heterosexual masculinity, they also set in motion gender-blending narratives

    The crisis of public sector trade unionism: evidence from the Mid Staffordshire hospital crisis

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    This article contends that there is a growing, if uneven, crisis in public sector trade unionism masked by relatively high membership figures that obscure a weakening of trade unions in the workplace, leaving hollowed out organisation vulnerable to further legislative and employer-led onslaughts. The weakening is not inevitable but to overcome it requires a refocusing of organising efforts on the everyday concerns of members such as understaffing and the provision of better public services. Only with an engaged membership will national issues and wider campaigns have material force. Having outlined a general argument, the article takes as illustrative the nature and performance of trade unions, and particularly UNISON, during the Mid Staffordshire hospital crisis

    Deletion of the protein tyrosine phosphatase PTPN22 for adoptive T cell therapy facilitates CTL effector function but promotes T cell exhaustion

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    Background: Adoptive cell therapy (ACT) is a promising strategy for treating cancer, yet it faces several challenges such as lack of long-term protection due to T cell exhaustion induced by chronic TCR stimulation in the tumor microenvironment. One benefit of ACT, however, is that it allows for cellular manipulations, such as deletion of the phosphotyrosine phosphatase non-receptor type 22 (PTPN22), which improves CD8+ T cell antitumor efficacy in ACT. We tested whether Ptpn22KO cytolytic T cells (CTLs) were also more effective than Ptpn22WT CTL in controlling tumors in scenarios that favor T cell exhaustion. Methods: Tumor control by Ptpn22WT and Ptpn22KO CTL was assessed following adoptive transfer of low numbers of CTL to mice with subcutaneously implanted MC38 tumors. Tumor infiltrating lymphocytes were isolated for analysis of effector functions. An in vitro assay was established to compare CTL function in response to acute and chronic restimulation with antigen-pulsed tumor cells. The expression of effector and exhaustion-associated proteins by Ptpn22WT and Ptpn22KO T cells was followed over time in vitro and in vivo using the ID8 tumor model. Finally, the effect of PD-1 and TIM-3 blockade on Ptpn22KO CTL tumor control was assessed using monoclonal antibodies and CRISPR/Cas9-mediated knockout. Results: Despite having improved effector function at the time of transfer, Ptpn22KO CTL became more exhausted than Ptpn22WT CTL, characterized by more rapid loss of effector functions, and earlier and higher expression of inhibitory receptors (IRs), particularly the terminal exhaustion marker TIM-3. TIM-3 expression, under the control of the transcription factor NFIL3, was induced by IL-2 signaling which was enhanced in Ptpn22KO cells. Antitumor responses of Ptpn22KO CTL were improved following PD-1 blockade in vivo, yet knockout or antibody-mediated blockade of TIM-3 did not improve but further impaired tumor control, indicating TIM-3 signaling itself did not drive the diminished function seen in Ptpn22KO CTL. Conclusions: This study questions whether TIM-3 plays a role as an IR and highlights that genetic manipulation of T cells for ACT needs to balance short-term augmented effector function against the risk of T cell exhaustion in order to achieve longer-term protection

    Intense Transpositional Activity of Insertion Sequences in an Ancient Obligate Endosymbiont

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    The streamlined genomes of ancient obligate endosymbionts generally lack transposable elements, such as insertion sequences (IS). Yet, the genome of Wolbachia, one of the most abundant bacterial endosymbionts on Earth, is littered with IS. Such a paradox raises the question as to why there are so many ISs in the genome of this ancient endosymbiont. To address this question, we investigated IS transpositional activity in the unculturable Wolbachia by tracking the evolutionary dynamics and history of ISWpi1 elements. We show that 1) ISWpi1 is widespread in Wolbachia, being present in at least 55% of the 40 sampled strains, 2) ISWpi1 copies exhibit virtually identical nucleotide sequences both within and among Wolbachia genomes and possess an intact transposase gene, 3) individual ISWpi1 copies are differentially inserted among Wolbachia genomes, and 4) ISWpi1 occurs at variable copy numbers among Wolbachia genomes. Collectively, our results provide compelling evidence for intense ISWpi1 transpositional activity and frequent ISWpi1 horizontal transmission among strains during recent Wolbachia evolution. Thus, the genomes of ancient obligate endosymbionts can carry high loads of functional and transpositionally active transposable elements. Our results also indicate that Wolbachia genomes have experienced multiple and temporally distinct ISWpi1 invasions during their evolutionary history. Such recurrent exposition to new IS invasions may explain, at least partly, the unusually high density of transposable elements found in the genomes of Wolbachia endosymbionts
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