4,226 research outputs found
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Firebreak (SPUR) project report: young people's views on healthy and abusive relationships
A FEROS spectroscopic study of the extreme O supergiant He 3-759
We present a study of the extreme O-type supergiant He 3-759 using new
high-resolution FEROS data, revealing that it is a near spectroscopic twin of
HD 151804 (O8 Iaf). We investigate the extinction towards He 3-759 using a
variety of methods, revealing A_V ~ 4.7 mag. If we assume He 3-759 has an
identical absolute K-band magnitude to HD 151804 we find that it lies in the
Sagittarius-Carina spiral arm at a distance of ~6.5 kpc. We derive the physical
and wind properties for He 3-759, revealing T* = 30.5 kK, log L/L(sun) = 5.9
and dM/dt = 10^-5.17 M(sun)/yr for a clumped wind whose terminal velocity is
estimated at 1000 km/s. The atmosphere of He 3-759 is enriched in helium (X_He
= 49%) and nitrogen (X_N = 0.3%). A reanalysis of HD 151804 and HD 152408
(WN9ha) reveals similar parameters except that the WN9ha star possesses a
stronger wind and reduced surface hydrogen content. HD 151804 and HD 152408 lie
within the Sco OB1 association, with initial masses of ~60 M(sun) and ages ~2.7
Myr, consistent with NGC 6231 cluster members using standard Geneva isochrones.
Improved agreement with observed surface abundances are obtained for similar
initial masses with more recent Geneva group predictions from which higher ages
of ~3.75 Myr are obtained. No young, massive star cluster is known to be
associated with He 3-759.Comment: 6 pages, 4 figures, accepted for A&
Metallicity in the Galactic Center: The Arches cluster
We present a quantitative spectral analysis of five very massive stars in the
Arches cluster, located near the Galactic center, to determine stellar
parameters, stellar wind properties and, most importantly, metallicity content.
The analysis uses a new technique, presented here for the first time, and uses
line-blanketed NLTE wind/atmosphere models fit to high-resolution near-infrared
spectra of late-type nitrogen-rich Wolf-Rayet stars and OfI+ stars in the
cluster. It relies on the fact that massive stars reach a maximum nitrogen
abundance that is related to initial metallicity when they are in the WNL
phase. We determine the present-day nitrogen abundance of the WNL stars in the
Arches cluster to be 1.6% (mass fraction) and constrain the stellar metallicity
in the cluster to be solar. This result is invariant to assumptions about the
mass-luminosity relationship, the mass-loss rates, and rotation speeds. In
addition, from this analysis, we find the age of the Arches cluster to be
2-2.5Myr, assuming coeval formation
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The gendering of violent crime: towards a human rights approach
This article reveals the diverse threats violent masculinities pose to human rights, especially females, in view of the idea that 'all things are equal now' between the genders. In the UK the Human Rights Act (1998) has sustained existing safeguards for the mainly male perpetrators of violence, but the needs of some female victims of domestic violence remain unmet. Contemporaneously, mainly female crime victims are vulnerable to violations of their basic human rights. The analysis in this paper identifies and interrogates the negative consequences of the principles of modernisation and six drivers of crime control underpinning government approaches since the late 1990s to dealing with violence against women in the context of general approaches to victimisation. Alongside issues relating to the receding influence of the state our argument is that a human rights-informed approach reveals not only the deficiencies and contradictions of government policy affecting change, but provides a vehicle for embedding a more comprehensive way of safeguarding human rights in practice
Perineal massage in labour and prevention of perineal trauma: randomised controlled trial
Objective: To determine the effects of perineal massage in the second stage of labour on perineal outcomes. Design: Randomised controlled trial. Participants: At 36 weeks' gestation, women expecting normal birth of a singleton were asked to join the study. Women became eligible to be randomised in labour if they progressed to full dilatation of the cervix or 8 cm or more if nulliparous or 5 cm or more if multiparous. 1340 were randomised into the trial. Intervention: Massage and stretching of the perineum during the second stage of labour with a water soluble lubricant. Main outcome measures: Primary outcomes: rates of intact perineum, episiotomies, and first, second, third, and fourth degree tears. Secondary outcomes: pain at three and 10 days postpartum and pain, dyspareunia, resumption of sexual intercourse, and urinary and faecal incontinence and urgency three months postpartum. Results: Rates of intact perineums, first and second degree tears, and episiotomies were similar in the massage and the control groups. There were fewer third degree tears in the massage group (12 (1.7%) v 23 (3.6%); absolute risk 2.11, relative risk 0.45; 95% confidence interval 0.23 to 0.93, P<0.04), though the trial was underpowered to measure this rarer outcome. Groups did not differ in any of the secondary outcomes at the three assessment points. Conclusions: The practice of perineal massage in labour does not increase the likelihood of an intact perineum or reduce the risk of pain, dyspareunia, or urinary and faecal problems.Georgina Stamp, Gillian Kruzins, Caroline Crowthe
The question of Early Lapita settlements in Remote Oceania and reliance on horticulture revisited: new evidence from plant microfossil studies at Reef/Santa Cruz, south-east Solomon Islands
Since the earliest discoveries of Lapita sites in Remote Oceania there has been ongoing debate about the nature of Pacific island colonisation. In the 1970s, based on the archaeological material from the SE-RF-2 and SE-RF-6 sites on the Reef Islands in the SE Solomons, Roger Green proposed that early Lapita communities there must have relied on horticulture as the mainstay of subsistence. Our analyses of phytoliths and starch in sediments and on pottery has found evidence for burning, food preparation and cooking in conjunction with a suite of wild and domesticated plants indicative of horticulture. Starch and phytoliths from seeded Australimusa (syn: Callimusa) bananas as well as domesticated Eumusa (syn: Musa) bananas were recovered, as well as Colocasia esculenta (taro) starch, and Metroxylon sp. (sago palm) phytoliths. Hence, Green’s early hypothesis finds support, but more analyses, together with more precise dating are needed to clarify the time taken to establish sustainable horticulture. The importation of selected plants is confirmed, with potential sources being the Bismarck region or stop-over islands along the way. This was followed by ongoing on-site breeding and/or new introductions from further human migrations into the region and establishment of trade and exchange networks.Introduction - Site locations and background Methods - Pottery - Sediments - Microfossil recording and identification Results - Starch Analysis - Phytolith Analysis SE-RF-2 SE-RF-6 Musaceae starch Musaceae phytoliths Discussion Conclusio
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