909 research outputs found

    Stellar Proper Motions in the Galactic Bulge from deep HST ACS/WFC Photometry

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    We present stellar proper motions in the Galactic bulge from the Sagittarius Window Eclipsing Extrasolar Search (SWEEPS) project using ACS/WFC on HST. Proper motions are extracted for more than 180,000 objects, with >81,000 measured to accuracy better than 0.3 mas/yr in both coordinates. We report several results based on these measurements: 1. Kinematic separation of bulge from disk allows a sample of >15,000 bulge objects to be extracted based on >6-sigma detections of proper motion, with <0.2% contamination from the disk. This includes the first detection of a candidate bulge Blue Straggler population. 2. Armed with a photometric distance modulus on a star by star basis, and using the large number of stars with high-quality proper motion measurements to overcome intrinsic scatter, we dissect the kinematic properties of the bulge as a function of distance along the line of sight. This allows us to extract the stellar circular speed curve from proper motions alone, which we compare with the circular speed curve obtained from radial velocities. 3. We trace the variation of the {l,b} velocity ellipse as a function of depth. 4. Finally, we use the density-weighted {l,b} proper motion ellipse produced from the tracer stars to assess the kinematic membership of the sixteen transiting planet candidates discovered in the Sagittarius Window; the kinematic distribution of the planet candidates is consistent with that of the disk and bulge stellar populations.Comment: 71 pages, 30 figures, ApJ Accepte

    Delineating the Implications of Dispersing Teams and Teleworking in an Agile UK Construction Sector

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    A scientometric analysis of extant literature is conducted to elucidate upon the practicality of teleworking throughout industry as a prelude to prescribing a bespoke conceptual adoption model that embeds innovative digital technologies to facilitate teleworking for construction professionals. The model is premised upon the Royal Institute of British Architects (RIBA) work stages and illustrates how technologies are being used at each incremental stage. An interpretivist philosophy and inductive reasoning were adopted using a sample of longitudinal secondary data contained within pertinent extant literature, where each publication constitutes a unit of analysis. The qualitative scientometric software VOSviewer and Voyant Tools were utilised to examine emergent research trends, with further manual review of prominent papers contained within the sample dataset. Four distinct historical advances are delineated in a timeline that describes the evolution of home working from the 1970s through to the present day (and during the global COVID-19 pandemic). Key milestones delineated indicate how technological advances have created new opportunities for teleworking. The research indicates that an acceleration of digital advances has engendered modernity in contemporary work location patterns and that these offer potentials to reduce the environmental impact of anthropogenic activities. This unique study highlights how COVID-19 and available digital technologies have shaped the future of teleworking from home and the potential environmental impact of such. This concludes by signposting directions for future research into the adoption of teleworking at the organisational level and establishing the cost and environmental savings to businesses from abandoning the traditional model of employer-based workin

    Notes on a scandal: the official enquiry into deviance and corruption in New Zealand police

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    Since 2004, the New Zealand Police Service has been engulfed by a series of scandals relating to allegations that officers have committed rape and sexual assault and conducted inappropriate sexual relations with vulnerable people. Moreover, it has been claimed that other officers engaged in corrupt practices to thwart the investigation and prosecution of criminal behaviour of police officers. In 2007, a Commission of Inquiry report established a program of reform intended to shape the future direction of the police service. This article provides an overview of these scandals, the context in which they have emerged, and the political and policing response to them. The analysis contained in the Commission report is compared with that offered by comparable investigations of police deviance and corruption in other countries. The methodological and conceptual limitations of the Commission are outlined and the prospects of the recommendations are considered

    Nitrogen-limited mangrove ecosystems conserve N through dissimilatory nitrate reduction to ammonium

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    Earlier observations in mangrove sediments of Goa, India have shown denitrification to be a major pathway for N loss1. However, percentage of total nitrate transformed through complete denitrification accounted for <0–72% of the pore water nitrate reduced. Here, we show that up to 99% of nitrate removal in mangrove sediments is routed through dissimilatory nitrate reduction to ammonium (DNRA). The DNRA process was 2x higher at the relatively pristine site Tuvem compared to the anthropogenically-influenced Divar mangrove ecosystem. In systems receiving low extraneous nutrient inputs, this mechanism effectively conserves and re-circulates N minimizing nutrient loss that would otherwise occur through denitrification. In a global context, the occurrence of DNRA in mangroves has important implications for maintaining N levels and sustaining ecosystem productivity. For the first time, this study also highlights the significance of DNRA in buffering the climate by modulating the production of the greenhouse gas nitrous oxide

    The Grizzly, February 15, 2000

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    UC Students Debate Pros, Cons of Pledging On Campus • Feelings of Brotherhood, Sisterhood Prevalent During Pledging Process • Employment Available for Graduating Seniors • True Love: Sorrow and Devotion • Hackers, Hijackers, and the Wide World of Sports • The Greeks Agree: Pledges Have no Free Will • Pledging: What\u27s the Big Deal Anyway? • muMs Schemes at Ursinus • Pat McGee to Jam at Ursinus • Music Review: The Alligator Blues Band • Gymnastics Tops RIC with Season High Score • Intramural 3 on 3 Action: Brains vs. Brute • Indoor Track Steps Up to Eight Way Challenge • Ursinus Wrestling Battles for 4-1 • Sports Profile: Shana Goanehttps://digitalcommons.ursinus.edu/grizzlynews/1459/thumbnail.jp

    Wheat-barley hybridization – the last forty years

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    Abstract Several useful alien gene transfers have been reported from related species into wheat (Triticum aestivum), but very few publications have dealt with the development of wheat/barley (Hordeum vulgare) introgression lines. An overview is given here of wheat 9 barley hybridization over the last forty years, including the development of wheat 9 barley hybrids, and of addition and translocation lines with various barley cultivars. A short summary is also given of the wheat 9 barley hybrids produced with other Hordeum species. The meiotic pairing behaviour of wheat 9 barley hybrids is presented, with special regard to the detection of wheat– barley homoeologous pairing using the molecular cytogenetic technique GISH. The effect of in vitro multiplication on the genome composition of intergeneric hybrids is discussed, and the production and characterization of the latest wheat/barley translocation lines are presented. An overview of the agronomical traits (b-glucan content, earliness, salt tolerance, sprouting resistance, etc.) of the newly developed introgression lines is given. The exploitation and possible use of wheat/barley introgression lines for the most up-to-date molecular genetic studies (transcriptome analysis, sequencing of flow-sorted chromosomes) are also discussed

    Increased Sensitivity to Broadly Neutralizing Antibodies of End-Stage Disease R5 HIV-1 Correlates with Evolution in Env Glycosylation and Charge

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    BACKGROUND: Induction of broadly neutralizing antibodies, such as the monoclonal antibodies IgGb12, 2F5 and 2G12, is the objective of most antibody-based HIV-1 vaccine undertakings. However, despite the relative conserved nature of epitopes targeted by these antibodies, mechanisms underlying the sensitivity of circulating HIV-1 variants to broadly neutralizing antibodies are not fully understood. Here we have studied sensitivity to broadly neutralizing antibodies of HIV-1 variants that emerge during disease progression in relation to molecular alterations in the viral envelope glycoproteins (Env), using a panel of primary R5 HIV-1 isolates sequentially obtained before and after AIDS onset. PRINCIPAL FINDINGS: HIV-1 R5 isolates obtained at end-stage disease, after AIDS onset, were found to be more sensitive to neutralization by TriMab, an equimolar mix of the IgGb12, 2F5 and 2G12 antibodies, than R5 isolates from the chronic phase. The increased sensitivity correlated with low CD4(+) T cell count at time of virus isolation and augmented viral infectivity. Subsequent sequence analysis of multiple env clones derived from the R5 HIV-1 isolates revealed that, concomitant with increased TriMab neutralization sensitivity, end-stage R5 variants displayed envelope glycoproteins (Envs) with reduced numbers of potential N-linked glycosylation sites (PNGS), in addition to increased positive surface charge. These molecular changes in Env also correlated to sensitivity to neutralization by the individual 2G12 monoclonal antibody (mAb). Furthermore, results from molecular modeling suggested that the PNGS lost at end-stage disease locate in the proximity to the 2G12 epitope. CONCLUSIONS: Our study suggests that R5 HIV-1 variants with increased sensitivity to broadly neutralizing antibodies, including the 2G12 mAb, may emerge in an opportunistic manner during severe immunodeficiency as a consequence of adaptive molecular Env changes, including loss of glycosylation and gain of positive charge
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