We present optical photometric and spectroscopic coverage of the superluminous supernova (SLSN) PS1-11ap, discovered with the Pan-STARRS1 Medium Deep Survey at z = 0.524. This intrinsically blue ...transient rose slowly to reach a peak magnitude of M
u
= −21.4 mag and bolometric luminosity of 8 × 1043 erg s−1 before settling on to a relatively shallow gradient of decline. The observed decline is significantly slower than those of the SLSNe-Ic which have been the focus of much recent attention. Spectroscopic similarities with the lower redshift SN2007bi and a decline rate similar to 56Co decay time-scale initially indicated that this transient could be a candidate for a pair instability supernova (PISN) explosion. Overall the transient appears quite similar to SN2007bi and the lower redshift object PTF12dam. The extensive data set, from 30 d before peak to 230 d after, allows a detailed and quantitative comparison with published models of PISN explosions. We find that the PS1-11ap data do not match these model explosion parameters well, supporting the recent claim that these SNe are not pair instability explosions. We show that PS1-11ap has many features in common with the faster declining SLSNe-Ic, and the light-curve evolution can also be quantitatively explained by the magnetar spin-down model. At a redshift of z = 0.524, the observer-frame optical coverage provides comprehensive rest-frame UV data and allows us to compare it with the SLSNe recently found at high redshifts between z = 2 and 4. While these high-z explosions are still plausible PISN candidates, they match the photometric evolution of PS1-11ap and hence could be counterparts to this lower redshift transient.
The intention of this paper it to open up debate within the environmental modelling and software (EMS) community on how best to respond to the increasing desire to evaluate the success of EMS ...projects in terms of outcomes rather than outputs. Outcomes in these regards are changes beyond the walls of the research organisation (typically to values, attitudes and behaviour). The authors recognise that outcome evaluation is essential in ensuring the relevance and effectiveness of activities. To date, however, there is a limited appreciation within the EMS community of the nature of the challenge inherent in outcome evaluations. The paper presents an exploratory analysis of the challenges that outcome assessment raises for EMS. It does so using mutually reinforcing conceptual and practical perspectives. The paper presents a conceptual framework of three loosely coupled phases – research, development and operations. The nature of activities and their interactions within these phases is outlined and the forms of evaluation associated with each stage set out. The paper notes how existing forms of evaluation (e.g. peer review, validation and relevance) underpin the delivery of outcomes but do not of themselves evaluate outcomes. The paper proposes that outcomes need conceptually to be seen as an element of complex social processes mediated by government, regulation, markets and the media rather than as simply another form of output from research and development projects. As such outcomes of EMS are: less easily tangible than are outputs; more likely to occur at a significant time lag after any intervention; more difficult to assign causality for and to be subject to significant contestation. Thus EMS activity, however well conducted technically, may only have a minor influence on outcomes and EMS practitioners will have limited control over those outcomes that do occur. The paper uses a series of linked EMS projects to populate the conceptual framework showing the role of evaluations in research, development and operations phases. The paper then presents two forms (quantitative and qualitative) of outcome evaluation used as part of an operational phase evaluation of a project communicating the consequences of climate change to remote-rural land managers in Scotland. The authors conclude that while the challenges of EMS evaluation can be met, there needs to be care from the EMS community not to raise expectations of outcomes that cannot be met.
We present observations and analysis of PS1-10bzj, a superluminous supernova (SLSN) discovered in the Pan-STARRS Medium Deep Survey at a redshift z = 0.650. Spectroscopically, PS1-10bzj is similar to ...the hydrogen-poor SLSNe 2005ap and SCP 06F6, though with a steeper rise and lower peak luminosity (M sub(bol) Asymptotically = to -21.4 mag) than previous events. We construct a bolometric light curve, and show that while PS1-10bzj's energetics were less extreme than previous events, its luminosity still cannot be explained by radioactive nickel decay alone. We explore both a magnetar spin-down and circumstellar interaction scenario and find that either can fit the data. PS1-10bzj is located in the Extended Chandra Deep Field South and the host galaxy is imaged in a number of surveys, including with the Hubble Space Telescope. The host is a compact dwarf galaxy (M sub(B) approximately - 18 mag, diameter lap800 pc), with a low stellar mass (M sub(*) approximately 2.4 x 10 super(7) M sub(odot)), young stellar population (tau sub(*) approximately 5 Myr), and a star formation rate of ~2-3 M sub(odot) yr super(-1). The specific star formation rate is the highest seen in an SLSN host so far (~100 Gyr super(-1)). We detect the OIII lambda4363 line, and find a low metallicity: 12 + (O/H) = 7.8 + or - 0.2 (Asymptotically = to 0.1 Z sub(odot)). Together, this indicates that at least some of the progenitors of SLSNe come from young, low-metallicity populations.
We describe the development of a high performance liquid chromatography mass spectrometry (HPLC-MS) method that allows the identification and quantitation of sterols in mammalian cells and tissues. ...Bulk lipids are extracted from biological samples by a modified Bligh/Dyer procedure in the presence of eight deuterated sterol standards to allow subsequent quantitation and determination of extraction efficiency. Sterols and other lipids are resolved by HPLC on a reverse-phase C18 column using a binary gradient of methanol and water, both containing 5mM ammonium acetate. Sterol identification is performed using an Applied Biosystems (Foster City, CA) 4000 QTRAP mass spectrometer equipped with a TurboV electrospray ionization source and operated in the positive (+) selected reaction monitoring (SRM) mode. The total run time of the analysis is 30 min. Sterols are quantitated by comparison of the areas under the elution curves derived from the detection of endogenous compounds and isotopically labeled standards. The sensitivity of the method for sterol detection ranges between 10 and 2000 fmol on-column. Cultured RAW 264.7 mouse macrophages contain many different sterols, including the liver X receptor (LXR) ligand 24,25-epoxycholesterol. Tissues such as mouse brain also contain large numbers of sterols, including 24(s)-hydroxycholesterol, which is involved in cholesterol turnover in the brain. The extraction procedure described is flexible and can be tailored to sample type or information sought. The instrumental analysis method is similarly adaptable and offers high selectivity and sensitivity.
Pig production in Ireland has gone through enormous changes during the past 60 yr, from pigs being primarily produced as a sideline on dairy farms, to an industry with one of the highest average herd ...sizes in Europe. This happened in part due to external pressure on the industry, whereby economies of scale were needed to compete with pigs produced in other countries, but largely due to the instigation of national programmes to support the pig industry through research, education and knowledge transfer. These efforts helped producers to take advantage of genetic improvements and monitor their own performance over time, as well as allowing for benchmarking of the national herd against other countries. The research programme initiated in the 1960s continues to grow and expand, providing the pig industry with internationally renowned data and knowledge in the areas of nutrition, animal welfare, the environment and energy use. Recent initiatives such as the establishment of the Teagasc and Irish Farmers Association Pig Joint Programme, and a Pig Health Check section in Animal Health Ireland, will help to promote further cross-collaboration between stakeholders in the pig industry, and enable it to rise to the challenges of the years ahead.
We present the Pan-STARRS1 discovery and light curves, and follow-up MMT and Gemini spectroscopy of an ultra-luminous supernova (ULSN; dubbed PS1-11bam) at a redshift of z = 1.566 with a peak ...brightness of MsubUV approximately -22.3 mag. PS1-11bam is one of the highest redshift spectroscopically confirmed SNe known to date. 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; the future combination of LSST and 30 m class telescopes promises to extend this technique to z ~ 4.
Background Socioeconomic differentials have been described in the risk of coronary heart disease (CHD) but the extent to which these differentials are explained by lifestyle factors has been examined ...to a lesser degree. We have examined the contribution of socio-economic factors to risk of CHD in a large cohort study in France and Northern Ireland. Methods In all, 10 593 men aged 50–59 years were examined between 1991 and 1994 in centres in Northern Ireland, Lille, Strasbourg, and Toulouse. Details were obtained for a number of socio-economic indicators from the men at the baseline examination. Men were also screened for evidence of CHD and followed annually by questionnaire for incident cases of coronary disease. Coronary events (coronary deaths, myocardial infarction, and angina) were documented by clinical records and were reviewed by an independent medical committee. Results In all, 842 men (8%) showed some evidence of CHD at screening examination and these men were more likely to be living in poorer material circumstances, be unemployed, or have had less full-time education than men without CHD at screening in both France and Northern Ireland. These relationships persisted following adjustment for all known risk factors for CHD. Among men who were initially free of CHD there were clear socio-economic differentials (years of full-time education, unemployment, and educational level) in the distribution of several risk factors for CHD, notably smoking habit (which differs in France and Northern Ireland), systolic blood pressure, body mass index, and fibrinogen. Total cholesterol in contrast showed no socio-economic differential whilst those with a shorter period of full-time education and the unemployed tended to be high consumers of alcohol. In this cohort of men free of CHD at baseline few socio-economic indicators showed relationships with risk of CHD by 5 years of follow-up. Only years in full education, educational level, and unemployment status when adjusted only for age and country showed significant relationships with CHD risk, but these became non-significant following adjustment for major CHD risk factors. Conclusions Socio-economic differentials in long-term risk of CHD are apparent in both cohorts of men from France and Northern Ireland, particularly in men with evidence of CHD at baseline. Among men free of CHD at baseline, although there is strong evidence of socio-economic differentials in cardiovascular risk factors these do not contribute independently to risk of CHD at 5 years of follow-up in this large cohort of men from France and Northern Ireland.
Abstract Objective: To determine the size of reduction in homocysteine concentrations produced by dietary supplementation with folic acid and with vitamins B-12 or B-6. Design: Meta-analysis of ...randomised controlled trials that assessed the effects of folic acid based supplements on blood homocysteine concentrations. Multivariate regression analysis was used to determine the effects on homocysteine concentrations of different doses of folic acid and of the addition of vitamin B-12 or B-6. Subjects: Individual data on 1114 people included in 12 trials. Findings: The proportional and absolute reductions in blood homocysteine produced by folic acid supplements were greater at higher pretreatment blood homocysteine concentrations (P<0.001) and at lower pretreatment blood folate concentrations (P<0.001). After standardisation to pretreatment blood concentrations of homocysteine of 12 μmol/l and of folate of 12 nmol/l (approximate average concentrations for Western populations), dietary folic acid reduced blood homocysteine concentrations by 25% (95% confidence interval 23% to 28%; P<0.001), with similar effects in the range of 0.5-5 mg folic acid daily. Vitamin B-12 (mean 0.5 mg daily) produced an additional 7% (3% to 10%) reduction in blood homocysteine. Vitamin B-6 (mean 16.5 mg daily) did not have a significant additional effect. Conclusions: Typically in Western populations, daily supplementation with both 0.5-5 mg folic acid and about 0.5 mg vitamin B-12 would be expected to reduce blood homocysteine concentrations by about a quarter to a third (for example, from about 12 μmol/l to 8-9 μmol/l). Large scale randomised trials of such regimens in high risk populations are now needed to determine whether lowering blood homocysteine concentrations reduces the risk of vascular disease. Key messages Higher blood homocysteine concentrations seem to be associated with higher risks of occlusive vascular disease and with lower blood concentrations of folate and vitamins B-12 and B-6 Proportional and absolute reductions in blood homocysteine concentrations with folic acid supplements are greater at higher pretreatment blood homocysteine concentrations and at lower pretreatment blood folate concentrations In typical Western populations, supplementation with both 0.5-5 mg daily folic acid and about 0.5 mg daily vitamin B-12 should reduce blood homocysteine concentrations by about a quarter to a third Large scale randomised trials of such regimens in people at high risk are now needed to determine whether lowering blood homocysteine concentrations reduces the risk of vascular disease
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