On the brightness distribution of type ia supernovae from violent white dwarf mergers

We investigate the brightness distribution expected for thermonuclear explosions that might result from the ignition of a detonation during the violent merger of white dwarf (WD) binaries. Violent WD mergers are a subclass of the canonical double degenerate scenario where two carbon-oxygen (CO) WDs merge when the larger WD fills its Roche lobe. Determining their brightness distribution is critical for evaluating whether such an explosion model could be responsible for a significant fraction of the observed population of Type Ia supernovae (SNe Ia). We argue that the brightness of an explosion realized via the violent merger model is mainly determined by the mass of Ni produced in the detonation of the primary COWD. To quantify this link, we use a set of sub-Chandrasekhar mass WD detonation models to derive a relationship between primary WD mass (m) and expected peak bolometric brightness (M). We use this m-M relationship to convert the masses of merging primary WDs from binary population models to a predicted distribution of explosion brightness. We also investigate the sensitivity of our results to assumptions about the conditions required to realize a detonation during violent mergers ofWDs. We find a striking similarity between the shape of our theoretical peak-magnitude distribution and that observed for SNe Ia: our model produces a M distribution that roughly covers the range and matches the shape of the one observed for SNe Ia. However, this agreement hinges on a particular phase of mass accretion during binary evolution: the primary WD gains ~0.15-0.35M? from a slightly evolved helium star companion. In our standard binary evolution model, such an accretion phase is predicted to occur for about 43 per cent of all binary systems that ultimately give rise to binary CO WD mergers. We also find that with high probability, violent WD mergers involving the most massive primaries (?1.3M?, which should produce bright SNe) have delay times ?500 Myr. © 2012 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.

The Right to a Fair Fight: Sporting Lessons on Consensual Harm

This article critically assesses the criminal law on consensual harm through an examination of the legality of fighting sports. The article begins by considering fighting sports such as bare-fisted prize fighting (dominant in the nineteenth century). It then, in historical chronology, examines the legality of professional boxing with gloves (dominant in the twentieth century). Doctrinally, the article reviews why and how, in a position adopted by the leading common law jurisdictions, fighting sports benefit from an application of the “well-established” category-based exceptions to the usual bodily harm threshold of consent in the criminal law. Centrally, fighting sports and doctrinal law on offenses against the person are juxtaposed against the theoretical boundaries of consent in the criminal law to examine whether and where the limit of the “right to be hurt” might lie. In sum, this article uses fighting sports as a case study to assess whether the criminal law generally can or should accommodate the notion of a fair fight, sporting or otherwise, predicated on the consent of the participants to the point that the individuals involved might be said, pithily, to have extended an open invite to harm.

Authority dependence and judgments of utilitarian harm

Three studies tested the conditions under which people judge utilitarian harm to be authority dependent (i.e., whether its right or wrongness depends on the ruling of an authority). In Study 1, participants judged the right or wrongness of physical abuse when used as an interrogation method anticipated to yield useful information for preventing future terrorist attacks. The ruling of the military authority towards the harm was manipulated (prohibited vs. prescribed) and found to significantly influence judgments of the right or wrongness of inflicting harm. Study 2 established a boundary condition with regards to the influence of authority, which was eliminated when the utility of the harm was definitely obtained rather than forecasted. Finally, Study 3 replicated the findings of Studies 1-2 in a completely different context—an expert committee’s ruling about the harming of chimpanzees for biomedical research. These results are discussed as they inform ongoing debates regarding the role of authority in moderating judgments of complex and simple harm. 2013 Elsevier B.V. © All rights reserved.

SN 2010LP - A type IA supernova from a violent merger of two carbon-oxygen white dwarfs

SN 2010lp is a subluminous Type Ia supernova (SN Ia) with slowly evolving lightcurves. Moreover, it is the only subluminous SN Ia observed so far that shows narrow emission lines of [O I] in late-time spectra, indicating unburned oxygen close to the center of the ejecta. Most explosion models for SNe Ia cannot explain the narrow [O I] emission. Here, we present hydrodynamic explosion and radiative transfer calculations showing that the violent merger of two carbon-oxygen white dwarfs of 0.9 and 0.76 M adequately reproduces the early-time observables of SN 2010lp. Moreover, our model predicts oxygen close to the center of the explosion ejecta, a pre-requisite for narrow [O I] emission in nebular spectra as observed in SN 2010lp. © 2013. The American Astronomical Society. All rights reserved.

Rejection, Shaming, Enclosure, and Moving On: Variant Experiences and Meaning Among Loyalist Former Prisoners:Variant Experiences and Meaning Among Loyalist Former Prisoners

This article unpacks the variant meanings, perceptions, and experiences of violent enactment and stigmatic shaming among loyalists with regard to rejection, harm, and masking. What we locate is a landscape of variable emotions, experiences, neutralization techniques, dependences, and embedded forms of fatalism as well as resilience. Attending to those alternate positions and well-beings is important in considering the capacity of re-integration and the presently uneven nature of it. In adopting an account-driven format we present and analyze how involvement in violent conflict can, on the one hand, provoke persistence and senses of transitional thinking and on the other engender rejection and related fatalistic attitudes.

A computational intelligent approach to multi-factor analysis of violent crime information systems

Various scientific studies have explored the causes of violent behaviour from different perspectives, with psychological tests, in particular, applied to the analysis of crime factors. The relationship between bi-factors has also been extensively studied including the link between age and crime. In reality, many factors interact to contribute to criminal behaviour and as such there is a need to have a greater level of insight into its complex nature. In this article we analyse violent crime information systems containing data on psychological, environmental and genetic factors. Our approach combines elements of rough set theory with fuzzy logic and particle swarm optimisation to yield an algorithm and methodology that can effectively extract multi-knowledge from information systems. The experimental results show that our approach outperforms alternative genetic algorithm and dynamic reduct-based techniques for reduct identification and has the added advantage of identifying multiple reducts and hence multi-knowledge (rules). Identified rules are consistent with classical statistical analysis of violent crime data and also reveal new insights into the interaction between several factors. As such, the results are helpful in improving our understanding of the factors contributing to violent crime and in highlighting the existence of hidden and intangible relationships between crime factors.

Degradation, Harm and Survival in a Women’s Prison:Special Issue on Gendered Violence

This article is derived in in-depth qualitative research in the women’s unit of a male prison in Northern Ireland. The researchers had unprecedented observational and interview access and moved freely within the unit including the punishment block. What follows focuses primarily on the experiences of women and girls, recording their accounts of the impact on their lives of a harsh and neglectful regime. It demonstrates how the institutionalisation of violation and neglect within women’s prisons is often gender specific. Finally, it considers the key research recommendations, noting official responses.

Research Ethics in Divided and Violent Societies: Seizing the Ethical Opportunity

This chapter explores how to conduct social research in divided and violent societies by developing the concept of the ‘ethical opportunity’. The ‘ethical opportunity’ is situated in a brief discussion of ‘action’ and feminist approaches to research. It argues that seizing the ethical opportunity requires researchers to: plan for their personal safety, plan for participants’ personal safety and plan how they will communicate and disseminate their results. It draws on the author’s personal experience researching in South Africa, Zimbabwe and Northern Ireland, concluding that it is in the communication and dissemination phase that researchers’ hopes for ‘making a difference’ may be realised or dashed. It cautions would-be researchers to manage their own – and research participants’ – expectations about what social research can achieve. Its effects may not often be as transforming and liberating as idealistic researchers hope for, but that should not dissuade them from striving towards those ends.

Accumulating research: a systematic account of how cumulative meta-analyses would have provided knowledge, improved health, reduced harm and saved resources

BACKGROUND: "Cumulative meta-analysis" describes a statistical procedure to calculate, retrospectively, summary estimates from the results of similar trials every time the results of a further trial in the series had become available. In the early 1990 s, comparisons of cumulative meta-analyses of treatments for myocardial infarction with advice promulgated through medical textbooks showed that research had continued long after robust estimates of treatment effects had accumulated, and that medical textbooks had overlooked strong, existing evidence from trials. Cumulative meta-analyses have subsequently been used to assess what could have been known had new studies been informed by systematic reviews of relevant existing evidence and how waste might have been reduced.

METHODS AND FINDINGS: We used a systematic approach to identify and summarise the findings of cumulative meta-analyses of studies of the effects of clinical interventions, published from 1992 to 2012. Searches were done of PubMed, MEDLINE, EMBASE, the Cochrane Methodology Register and Science Citation Index. A total of 50 eligible reports were identified, including more than 1,500 cumulative meta-analyses. A variety of themes are illustrated with specific examples. The studies showed that initially positive results became null or negative in meta-analyses as more trials were done; that early null or negative results were over-turned; that stable results (beneficial, harmful and neutral) would have been seen had a meta-analysis been done before the new trial; and that additional trials had been much too small to resolve the remaining uncertainties.

CONCLUSIONS: This large, unique collection of cumulative meta-analyses highlights how a review of the existing evidence might have helped researchers, practitioners, patients and funders make more informed decisions and choices about new trials over decades of research. This would have led to earlier uptake of effective interventions in practice, less exposure of trial participants to less effective treatments, and reduced waste resulting from unjustified research.