757 research outputs found

    Testing Women’s Athletic Shirts: Which is Better?

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    Erica Bell is an undergraduate student in the School of Human Ecology at Louisiana Tech University. Janay Williams is an undergraduate student in the School of Human Ecology at Louisiana Tech University. Jacoby Clark is an undergraduate student in Computer Information Systems in the College of Business at Louisiana Tech University. Kathleen Heiden is an Associate Professor in the School of Human Ecology at Louisiana Tech University

    Accelerated Recombination due to Resonant Deexcitation of Metastable States

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    In a recombining plasma the metastable states are known to accumulate population thereby slowing down the recombination process. We show that an account of the doubly-excited autoionizing states, formed due to collisional recombination of metastable ions, results in a significant acceleration of recombination. A fully time-dependent collisional-radiative (CR) modeling for stripped ions of carbon recombining in a cold dense plasma demonstrates an order of magnitude faster recombination of He-like ions. The CR model used in calculations is discussed in detail.Comment: 15 pages, 4 figures; to be published in JQSR

    VdBH 222: a starburst cluster in the inner Milky Way

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    Context. It has been suggested that the compact open cluster VdBH 222 is a young massive distant object.Aims. We set out to characterise VdBH 222 using a comprehensive set of multi-wavelength observations.Methods.We obtained multi-band optical (UBVR) and near-infrared (JHKS) photometry of the cluster field, as well as multi-object and long-slit optical spectroscopy for a large sample of stars in the field. We applied classical photometric analysis, as well as more sophisticated methods using the CHORIZOS code, to determine the reddening to the cluster. We then plotted dereddened HR diagrams and determined cluster parameters via isochrone fitting.Results. We have identified a large population of luminous supergiants confirmed as cluster members via radial velocity measurements. We find nine red supergiants (plus one other candidate) and two yellow supergiants. We also identify a large population of OB stars. Ten of them are bright enough to be blue supergiants. The cluster lies behind ‚Čą7.5 mag of extinction for the preferred value of RV = 2.9. Isochrone fitting allows for a narrow range of ages between 12 and 16 Ma. The cluster radial velocity is compatible with distances of ~6 and ~10 kpc. The shorter distance is inconsistent with the age range and Galactic structure. The longer distance implies an age ‚Čą 12 Ma and a location not far from the position where some Galactic models place the far end of the Galactic bar.Conclusions. VdBH 222 is a young massive cluster with a likely mass >20 000 M‚äô. Its population of massive evolved stars is comparable to that of large associations, such as Per OB1. Its location in the inner Galaxy, presumably close to the end of the Galactic bar, adds to the increasing evidence for vigorous star formation in the inner regions of the Milky Way

    The Evolution of the Kinematics of Nebular Shells in Planetary Nebulae in the Milky Way Bulge

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    We study the line widths in the [\ion{O}{3}]őĽ\lambda5007 and HőĪ\alpha lines for two groups of planetary nebulae in the Milky Way bulge based upon spectroscopy obtained at the Observatorio Astron\'omico Nacional in the Sierra San Pedro M\'artir (OAN-SPM) using the Manchester Echelle Spectrograph. The first sample includes objects early in their evolution, having high Hő≤\beta luminosities, but [\ion{O}{3}]őĽ5007/Hő≤<3\lambda 5007/\mathrm H\beta < 3. The second sample comprises objects late in their evolution, with \ion{He}{2} őĽ4686/Hő≤>0.5\lambda 4686/\mathrm H\beta > 0.5. These planetary nebulae represent evolutionary phases preceeding and following those of the objects studied by Richer et al. (2008). Our sample of planetary nebulae with weak [\ion{O}{3}]őĽ\lambda5007 has a line width distribution similar to that of the expansion velocities of the envelopes of AGB stars, and shifted to systematically lower values as compared to the less evolved objects studied by Richer et al. (2008). The sample with strong \ion{He}{2} őĽ4686\lambda 4686 has a line width distribution indistinguishable from that of the more evolved objects from Richer et al. (2008), but a distribution in angular size that is systematically larger and so they are clearly more evolved. These data and those of Richer et al. (2008) form a homogeneous sample from a single Galactic population of planetary nebulae, from the earliest evolutionary stages until the cessation of nuclear burning in the central star. They confirm the long-standing predictions of hydrodynamical models of planetary nebulae, where the kinematics of the nebular shell are driven by the evolution of the central star.Comment: accepted for publication in the Astrophysical Journa

    Understanding Persistent Non-compliance in a Remote, Large-Scale Marine Protected Area

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    UIDB/04647/2020 UIDP/04647/2020Area coverage of large-scale marine protected areas (MPAs) (LSMPAs, > 100,000 km2) is rapidly increasing globally. Their effectiveness largely depends on successful detection and management of non-compliance. However, for LSMPAs this can be difficult due to their large size, often remote locations and a lack of understanding of the social drivers of non-compliance. Taking a case-study approach, we review current knowledge of illegal fishing within the British Indian Ocean Territory (BIOT) LSMPA. Data stemming from enforcement reports (2010‚Äď20), and from fieldwork in fishing communities (2018‚Äď19) were combined to explore and characterise drivers of non-compliance. Enforcement data included vessel investigation reports (n = 188), transcripts of arrests (20) and catch seizures (58). Fieldwork data included fisher interviews (95) and focus groups (12), conducted in two communities in Sri Lanka previously associated with non-compliance in BIOT LSMPA. From 2010 to 2020, there were 126 vessels suspected of non-compliance, 76% of which were Sri Lankan. The majority of non-compliant vessels targeted sharks (97%), catching an estimated 14,340 individuals during the study period. Sri Lankan vessels were primarily registered to one district (77%) and 85% operated from just two ports within the fieldwork sites. Social Network Analysis (SNA) showed that 66% of non-compliant vessels were linked by social ties, including sharing crew members, compared with only 34% of compliant vessels. Thematic analysis of qualitative data suggested that perceptions of higher populations of sharks and social ties between vessels may both be important drivers. We discuss our findings within a global context to identify potential solutions for LSMPA management.publishersversionpublishe

    Necessary and sufficient factors in employee downsizing? A qualitative comparative analysis of lay-offs in France and the UK, 2008-2013

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    Embedded in the literature on financialization and institutional approaches, this study is an examination of the causal factors of employee downsizing in two institutionally dissimilar settings, France and the UK, using the fuzzy sets variant of Qualitative Comparative Analysis. The findings show that the roughly equivalent use of large-scale lay-offs in the two countries is coupled with strikingly different causal factors. Our argument suggests the importance of complex causation whereby employee downsizing reflects the growing influence of financial considerations in the governance of companies, but its diffusion across countries is shaped by different configurations of institutional arrangements

    Study of measured pulsar masses and their possible conclusions

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    We study the statistics of 61 measured masses of neutron stars (NSs) in binary pulsar systems, including 18 double NS (DNS) systems, 26 radio pulsars (10 in our Galaxy) with white dwarf (WD) companions, 3 NSs with main-sequence companions, 13 NSs in X-ray binaries, and one undetermined system. We derive a mean value of M = 1.46 +/- 0.30 solar masses. When the 46 NSs with measured spin periods are divided into two groups at 20 milliseconds, i.e., the millisecond pulsar (MSP) group and others, we find that their mass averages are, respectively, M=1.57 +/- 0.35 solar masses and M=1.37+/- 0.23 solar masses. In the framework of the pulsar recycling hypothesis, this suggests that an accretion of approximately 0.2 solar mass is sufficient to spin up a neutron star and place it in the millisecond pulsar group. An empirical relation between the accreting mass and MSP spin period is \Delta M=0.43 (solar mass)(P/1 ms)^{-2/3}. UNlike the standard recycling process, if a MSP is formed by the accretion induced collapse (AIC) of a white dwarf with a mass less than Chandrasekha limit, e.g. 1.35 solar mass, then the binary MSPs involved in AICs is not be higher than 20%, which imposes a constraint on the AIC origin of MSPs.Comment: 6 pages, 5 figures, in press, Astronomy and Astrophysics 2011, 527, 8

    Relationship of television time with accelerometer-derived sedentary time: NHANES

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    CLARK, B. K., G. N. HEALY, E. A. H. WINKLER, P. A. GARDINER, T. SUGIYAMA, D. W. DUNSTAN, C. E. MATTHEWS, and N. OWEN. Relationship of Television Time with Accelerometer-Derived Sedentary Time: NHANES. Med. Sci. Sports Exerc., Vol. 43, No. 5, pp. 822-828, 2011. Purpose: To examine the relationship of self-reported television (TV) viewing time with accelerometer-derived total sedentary time and to determine whether it differs by subgroup. Methods: Using data for adults (>= 20 yr) from the 2003-2004 and 2005-2006 nationally representative US National Health and Nutrition Examination Surveys (NHANES; n = 5738), linear regression models examined the associations of categories of self-reported TV viewing time (< 1, 1, 2, 3, 4, and 95 h.d(-1)) with accelerometer-derived sedentary time (< 100 counts per minute; h.d(-1)). Spearman rho assessed the correlation between participants' rankings on the two measures. Analyses were stratified by gender, age, race/ethnicity, and, in the 2003-2004 NHANES cycle, by work status among working-aged adults (20-65 yr, n = 2069). Results: TV viewing time was significantly associated with sedentary time, with positive associations for all gender, age, race/ethnicity groups, and for those not working or working part-time, but not for those in full-time work. However, correlations between rankings of the measures were only "fair" overall (rho = 0.22) and were similar for all gender and racial/ethnic groups and for those of mid- and older age but not for those of younger age (20-39 yr, rho = 0.05). In the working-aged subgroup, there was also a fair correlation between the measures for those not working (rho = 0.22) but no significant correlation for those in part-time (rho = 0.14) or full-time work (rho = 0.03). Conclusions: Associations of TV viewing time with accelerometer-derived total sedentary time were statistically significant, but correlations were of only fair magnitude, and the strength of the relationship was not consistent across all population subgroups. These findings suggest that TV viewing time has an influence on overall sedentary time at a population level; however, measurement of sedentary time in other domains is also important

    Sovereign wealth funds, productivity and people: The impact of Norwegian Government Pension Fund‚ÄźGlobal investments in the United Kingdom

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    Sovereign wealth funds have an increasing presence in the global financial ecosystem, principally through their investments in equities, which, in turn, may influence HRM. This study examines the influence of the world's largest sovereign wealth fund, the Norwegian Government Pension Fund‚ÄźGlobal (NGPF‚ÄźG), on employment in its U.K. investee firms. We find that firms with NGPF‚ÄźG investment are significantly less likely to reduce their demand for labour, more specifically in the immediate aftermath of the 2008 financial crisis. When a drop in the demand for labour does occur, it is less extreme when compared to similar organisations without a NGPF‚ÄźG shareholding, and this is evident even in the case of relatively small NGPF‚ÄźG investments. These findings are in line with the fund's objective of promoting corporate sustainability and Norwegian values. We draw out the key implications of our findings for HR practice
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