298 research outputs found

    The first low-mass black hole x-ray binary identified in quiescence outside of a globular cluster

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    The observed relation between the X-ray and radio properties of low-luminosity accreting black holes (BHs) has enabled the identification of multiple candidate black hole X-ray binaries (BHXBs) in globular clusters (GCs). Here, we report an identification of the radio source VLA J213002.08+120904 (aka M15 S2), recently reported in Kirsten et al., as a BHXB candidate. They showed that the parallax of this flat-spectrum variable radio source indicates a - + 2.2 0.30.5 kpc distance, which identifies it as lying in the foreground of the GC M15. We determine the radio characteristics of this source and place a deep limit on the X-ray luminosity of ~4 × 1029 erg s.1. Furthermore, we astrometrically identify a faint red stellar counterpart in archival Hubble images with colors consistent with a foreground star; at 2.2 kpc, its inferred mass is 0.1-0.2Me. We rule out that this object is a pulsar, neutron star X-ray binary, cataclysmic variable, or planetary nebula, concluding that VLA J213002.08+120904 is the first accreting BHXB candidate discovered in quiescence outside of a GC. Given the relatively small area over which parallax studies of radio sources have been performed, this discovery suggests a much larger population of quiescent BHXBs in our Galaxy, 2.6 ± 104-1.7 × 108 BHXBs at 3× confidence, than has been previously estimated (~102-104) through population synthesis

    Grounds for engagement: Dissonances and overlaps at the intersection of contemporary civilizations analysis and postcolonial sociology

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    This article elucidates grounds for engagement between two fields of the social sciences engaged in critique of Eurocentrism: contemporary civilizations analysis and postcolonial sociology. Between the two fields there are both evident dissonances and points of potential dialogue and engagement. The article identifies three areas of high contention: divergent perceptions of essentialism, commitments to transformative politics and evaluations of the paradigm of multiple modernities. Despite extensive theoretical and normative differences, a notional intersection of the two fields is outlined in the form of three conceptual and methodological shifts. The first is a displacement of ideal typology. The second move is the most original. ‘Intercivilizational encounters’ and ‘intracivilizational encounters’ are re-cast as ‘intercivilizational engagement’. The goal is the demarcation of a discrete position based on a strong version of interaction that goes further than the notion of intercivilizational encounters recently re-developed in civilizational analysis. To illustrate potential grounds for engagement on this point, the article reviews the historiography of ‘connected histories’ and the insights of relational historians. Finally, the article urges for a nuanced definition of ‘region’ and deeper appreciation of the multiplicity of regionalisms as a meeting point for both fields of critique of Eurocentrism

    A Drastic Reduction in the Life Span of Cystatin C L68Q Carriers Due to Life-Style Changes during the Last Two Centuries

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    Hereditary cystatin C amyloid angiopathy (HCCAA) is an autosomal dominant disease with high penetrance, manifest by brain hemorrhages in young normotensive adults. In Iceland, this condition is caused by the L68Q mutation in the cystatin C gene, with contemporary carriers reaching an average age of only 30 years. Here, we report, based both on linkage disequilibrium and genealogical evidence, that all known copies of this mutation derive from a common ancestor born roughly 18 generations ago. Intriguingly, the genealogies reveal that obligate L68Q carriers born 1825 to 1900 experienced a drastic reduction in life span, from 65 years to the present-day average. At the same time, a parent-of-origin effect emerged, whereby maternal inheritance of the mutation was associated with a 9 year reduction in life span relative to paternal inheritance. As these trends can be observed in several different extended families, many generations after the mutational event, it seems likely that some environmental factor is responsible, perhaps linked to radical changes in the life-style of Icelanders during this period. A mutation with such radically different phenotypic effects in reaction to normal variation in human life-style not only opens the possibility of preventive strategies for HCCAA, but it may also provide novel insights into the complex relationship between genotype and environment in human disease

    Effect of HLA-DRB1 alleles and genetic variants on the development of neutralizing antibodies to interferon beta in the BEYOND and BENEFIT trials

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    BACKGROUND: Treatment of multiple sclerosis (MS) with interferon β can lead to the development of antibodies directed against interferon β that interfere with treatment efficacy. Several observational studies have proposed different HLA alleles and genetic variants associated with the development of antibodies against interferon β. OBJECTIVE: To validate the proposed genetic markers and to identify new markers. METHODS: Associations of genetic candidate markers with antibody presence and development were examined in a post hoc analysis in 941 patients treated with interferon β-1b in the Betaferon® Efficacy Yielding Outcomes of a New Dose (BEYOND) and BEtaseron®/BEtaferon® in Newly Emerging multiple sclerosis For Initial Treatment (BENEFIT) prospective phase III trials. All patients were treated with interferon β-1b for at least 6 months. In addition, a genome-wide association study was conducted to identify new genetic variants. RESULTS: We confirmed an increased risk for carriers of HLA-DRB1*04:01 (odds ratio (OR) = 3.3, p = 6.9 × 10-4) and HLA-DRB1*07:01 (OR = 1.8, p = 3.5 × 10-3) for developing neutralizing antibodies (NAbs). Several additional, previously proposed HLA alleles and genetic variants showed nominally significant associations. In the exploratory analysis, variants in the HLA region were associated with NAb development at genome-wide significance (OR = 2.6, p = 2.30 × 10-15). CONCLUSION: The contribution of HLA alleles and HLA-associated single-nucleotide polymorphisms (SNPs) to the development and titer of antibodies against interferon β was confirmed in the combined analysis of two multi-national, multi-center studies

    Antibacterial activity of traditional medicinal plants used by Haudenosaunee peoples of New York State

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    <p>Abstract</p> <p>Background</p> <p>The evolution and spread of antibiotic resistance, as well as the evolution of new strains of disease causing agents, is of great concern to the global health community. Our ability to effectively treat disease is dependent on the development of new pharmaceuticals, and one potential source of novel drugs is traditional medicine. This study explores the antibacterial properties of plants used in Haudenosaunee traditional medicine. We tested the hypothesis that extracts from Haudenosaunee medicinal plants used to treat symptoms often caused by bacterial infection would show antibacterial properties in laboratory assays, and that these extracts would be more effective against moderately virulent bacteria than less virulent bacteria.</p> <p>Methods</p> <p>After identification and harvesting, a total of 57 different aqueous extractions were made from 15 plant species. Nine plant species were used in Haudenosaunee medicines and six plant species, of which three are native to the region and three are introduced, were not used in traditional medicine. Antibacterial activity against mostly avirulent (<it>Escherichia coli, Streptococcus lactis</it>) and moderately virulent (<it>Salmonella typhimurium, Staphylococcus aureus</it>) microbes was inferred through replicate disc diffusion assays; and observed and statistically predicted MIC values were determined through replicate serial dilution assays.</p> <p>Results</p> <p>Although there was not complete concordance between the traditional use of Haudenosaunee medicinal plants and antibacterial activity, our data support the hypothesis that the selection and use of these plants to treat disease was not random. In particular, four plant species exhibited antimicrobial properties as expected (<it>Achillea millefolium, Ipomoea pandurata, Hieracium pilosella</it>, and <it>Solidago canadensis</it>), with particularly strong effectiveness against <it>S. typhimurium</it>. In addition, extractions from two of the introduced species (<it>Hesperis matronalis </it>and <it>Rosa multiflora</it>) were effective against this pathogen.</p> <p>Conclusions</p> <p>Our data suggest that further screening of plants used in traditional Haudenosaunee medicine is warranted, and we put forward several species for further investigation of activity against <it>S. typhimurium </it>(<it>A. millefolium, H. matronalis, I. pandurata, H. pilosella, R. multiflora, S. canadensis</it>).</p

    The piano music of Sterndale Bennett in the context of nineteenth-century pianism : a practice-based interpretive study with critical commentary

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    Sterndale Bennett (1816 - 75) made a significant contribution to piano music and pianism in London during the nineteenth-century, as evidenced by his substantial work list (see Appendix A). The aim of this thesis is to show how a knowledge of the performance practices of his time and of his own approach to style and interpretation can illuminate the performance of this repertoire. A secondary aim is to set this study within a clear historical framework and hence to make a strong connection between contextual and textual studies. An examination of his piano music and contemporary accounts of his piano playing reveal a conservative approach compared to other performers. The picture is amplified by an account of practices described in nineteenth-century writings on performance and of the differences between English and Viennese pianos. In the recordings, music by Sterndale Bennett is juxtaposed with music by selected predecessors and contemporaries, not only to show how his music relates to the nineteenth-century continuum, but also to present in sharp relief his special stylistic qualities. Some of the recordings reflect the work of members of the London Pianoforte School. The justification for this twentieth-century grouping is discussed in Chapter 1 in the context of London musical life and pianism in the nineteenthcentury, with reference to contemporary opinion-formers. The influence of Mozart and of the revival of Baroque keyboard music on Sterndale Bennett are also discussed. Publishing practices of the period are examined in Chapter 2, leading to a survey of Sterndale Bennett's sources and publications. Chapter 3 investigates approaches to nineteenth-century pianism, drawing on contemporary documents and secondary sources, comparing them with the preserved evidence we have regarding Sterndale Bennett's own stance on these matters. This process reveals, in many cases, that Sterndale Bennett represented a more scholarly and less commercial approach to piano playing than was prevalent among contemporaries such as Kalkbrenner, Thalberg and others. Finally, this study offers a paradigm for reinvigorating an historic but largely moribund repertoire incorporating it into contemporary practice.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
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