178 resultados para Galaxies: individual: M 51


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We present the Pan-STARRS1 discovery and light curves, and follow-up MMT and Gemini spectroscopy of an ultraluminous supernova (ULSN; dubbed PS1-11bam) at a redshift of z = 1.566 with a peak brightness of M UV ≈ -22.3 mag. PS1-11bam is one of the highest redshift spectroscopically confirmed SNe known to date. The spectrum exhibits broad absorption features typical of previous ULSNe (e.g., C II, Si III), and strong and narrow Mg II and Fe II absorption lines from the interstellar medium (ISM) of the host galaxy, confirmed by an [O II]λ3727 emission line at the same redshift. The equivalent widths of the Fe II λ2600 and Mg II λ2803 lines are in the top quartile of the quasar intervening absorption system distribution, but are weaker than those of gamma-ray burst intrinsic absorbers (i.e., GRB host galaxies). We also detect the host galaxy in pre-explosion Pan-STARRS1 data and find that its UV spectral energy distribution is best fit with a young stellar population age of τ* ≈ 15-45 Myr and a stellar mass of M * ≈ (1.1-2.6) × 109 M ⊙ (for Z = 0.05-1 Z ⊙). The star formation rate inferred from the UV continuum and [O II]λ3727 emission line is ≈10 M ⊙ yr-1, higher than in previous ULSN hosts. PS1-11bam provides the first direct demonstration that ULSNe can serve as probes of the ISM in distant galaxies. The depth and red sensitivity of PS1 are uniquely suited to finding such events at cosmologically interesting redshifts (z ~ 1-2); the future combination of LSST and 30 m class telescopes promises to extend this technique to z ~ 4.

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OBJECTIVES: Evaluate current data sharing activities of UK publicly funded Clinical Trial Units (CTUs) and identify good practices and barriers.

STUDY DESIGN AND SETTING: Web-based survey of Directors of 45 UK Clinical Research Collaboration (UKCRC)-registered CTUs.

RESULTS: Twenty-three (51%) CTUs responded: Five (22%) of these had an established data sharing policy and eight (35%) specifically requested consent to use patient data beyond the scope of the original trial. Fifteen (65%) CTUs had received requests for data, and seven (30%) had made external requests for data in the previous 12 months. CTUs supported the need for increased data sharing activities although concerns were raised about patient identification, misuse of data, and financial burden. Custodianship of clinical trial data and requirements for a CTU to align its policy to their parent institutes were also raised. No CTUs supported the use of an open access model for data sharing.

CONCLUSION: There is support within the publicly funded UKCRC-registered CTUs for data sharing, but many perceived barriers remain. CTUs are currently using a variety of approaches and procedures for sharing data. This survey has informed further work, including development of guidance for publicly funded CTUs, to promote good practice and facilitate data sharing.

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We observed 51 Peg, the first detected planet-bearing star, in a 55 ks XMM-Newton pointing and in 5 ks pointings each with Chandra HRC-I and ACIS-S. The star has a very low count rate in the XMM observation, but is clearly visible in the Chandra images due to the detectors' different sensitivity at low X-ray energies. This allows a temperature estimate for 51 Peg's corona of T⪉ 1 MK; the detected ACIS-S photons can be plausibly explained by emission lines of a very cool plasma near 200 eV. The constantly low X-ray surface flux and the flat-activity profile seen in optical Ca II data suggest that 51 Peg is a Maunder minimum star; an activity enhancement due to a Hot Jupiter, as proposed by recent studies, seems to be absent. The star's X-ray fluxes in different instruments are consistent with the exception of the HRC Imager, which might have a larger effective area below 200 eV than given in the calibration.

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This study assessed the effect of predisposition to perform harmful social behaviour, maternal rearing environment, and lactation environment on the responses of pigs to weaning at 3 or 5 weeks of age. Predisposed and non-predisposed gilts were selected as dams for this study at 7 weeks of age. Selection was based on behaviour in a

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Harris R. and Trainor M. (2007) Impact of government intervention on employment change and plant closure in Northern Ireland, 1983-97, Regional Studies 41, 51-63. Financial assistance to manufacturing industry is an important element of the industrial development policy in Northern Ireland. This paper uses the individual plant-level records of the Annual Respondents Database (ARD) for the Northern Ireland manufacturing sector (1983-97) matched to the plant-level details of financial support provided by the Industrial Development Board to examine the effect of selective financial assistance (SFA) on employment change and plant closure. It is found that SFA concentrated on protecting existing, rather than new, enterprises in terms of employment change. Using a hazard model, it is found that the receipt of SFA significantly reduced the probability of plant closure by, on average, between 15 and 24%.

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Background: Hip protectors are protective pads designed to cover the greater trochanter and attenuate or disperse the force of a fall sufficiently to prevent a hip fracture. Promising results from randomised controlled trials in nursing homes have resulted in hip protectors being widely recommended in the health care literature and in national guidelines. Objectives: The objectives of the study were to identify characteristics of individual residents, and the organisational features of the homes in which they live, which may affect adherence to wearing hip protectors. Design: An observational, correlation study designed to identify factors related to adherence. Setting: Forty nursing and residential homes in the UK. Participants: 1346 residents of the homes who were not confined to bed and with no pressure sore on the hip. Methods: The introduction of an evidence-based policy to offer Safehips hip protectors to residents free of charge and with support from a nurse facilitator. Adherence to wearing the hip protectors was observed over 72 weeks. Results: Initial acceptance of the hip protectors was 37.2%. Continued adherence was 23.9% at 24 weeks; 23.2% at 48 weeks; and 19.9% at 72 weeks. Greater adherence was associated with the following individual resident characteristics: a greater degree of dependency (95% CI 1.39 - m3.78) and cognitive impairment (95% CI 1.01 - 2.98); being male rather than female (95% CI 1.06 - 2.48). Greater adherence was also associated with the following organisational characteristics of homes: fewer changes of senior manager during the study period (95% CI 1.01 - 8.51), and being resident in a home with a resident profile showing a greater proportion of residents with a higher degree of dependency (95% CI 1.04 - 1.27). There was wide a variation in the degree of success in implementation between homes (adherence of 0 - 100% at 24 weeks). Conclusions: Those implementing a policy of introducing hip protectors into nursing and residential homes should consider targeting residents with cognitive impairment. Such residents are at greater risk of hip fracture and appear to be more likely to continue wearing hip protectors. Those charged with implementing changes inpractice or policy should consider how the context for implementation can be optimised to increase the likelihood of success.

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Abstract: Raman spectroscopy has been used for the first time to predict the FA composition of unextracted adipose tissue of pork, beef, lamb, and chicken. It was found that the bulk unsaturation parameters could be predicted successfully [R-2 = 0.97, root mean square error of prediction (RMSEP) = 4.6% of 4 sigma], with cis unsaturation, which accounted for the majority of the unsaturation, giving similar correlations. The combined abundance of all measured PUFA (>= 2 double bonds per chain) was also well predicted with R-2 = 0.97 and RMSEP = 4.0% of 4 sigma. Trans unsaturation was not as well modeled (R-2 = 0.52, RMSEP = 18% of 4 sigma); this reduced prediction ability can be attributed to the low levels of trans FA found in adipose tissue (0.035 times the cis unsaturation level). For the individual FA, the average partial least squares (PLS) regression coefficient of the 18 most abundant FA (relative abundances ranging from 0.1 to 38.6% of the total FA content) was R-2 = 0.73; the average RMSEP = 11.9% of 4 sigma. Regression coefficients and prediction errors for the five most abundant FA were all better than the average value (in some cases as low as RMSEP = 4.7% of 4 sigma). Cross-correlation between the abundances of the minor FA and more abundant acids could be determined by principal component analysis methods, and the resulting groups of correlated compounds were also well-predicted using PLS. The accuracy of the prediction of individual FA was at least as good as other spectroscopic methods, and the extremely straightforward sampling method meant that very rapid analysis of samples at ambient temperature was easily achieved. This work shows that Raman profiling of hundreds of samples per day is easily achievable with an automated sampling system.