Nature and Nurture in Dark Matter Halos

Cosmological simulations consistently predict specific properties of dark matter halos, but these have not yet led to a physical understanding that is generally accepted. This is especially true for the central regions of these structures. Recently two major themes have emerged. In one, the dark matter halo is primarily a result of the sequential accretion of primordial structure (ie `Nature'); while in the other, dynamical relaxation (ie `Nurture') dominates at least in the central regions. Some relaxation is however required in either mechanism. In this paper we accept the recently established scale-free sub-structure of halos as an essential part of both mechanisms. Consequently; a simple model for the central relaxation based on a self-similar cascade of tidal interactions, is contrasted with a model based on the accretion of adiabatically self-similar, primordial structure. We conclude that a weak form of this relaxation is present in the simulations, but that is normally described as the radial orbit instability.Comment: 25 pages, 3 figures, fig with parts 1 to d, fig 3 with parts a to

Sensitivity of a national coronial database for monitoring unnatural deaths among ex-prisoners in Australia

<p>Abstract</p> <p>Background</p> <p>The period immediately after release from custody is a time of marked vulnerability and increased risk of death for ex-prisoners. Despite this, there is currently no routine, national system for monitoring ex-prisoner mortality in Australia. This study subsequently aimed to evaluate the sensitivity of Australia's National Coroners Information System (NCIS) for identifying reportable deaths among prisoners and ex-prisoners.</p> <p>Findings</p> <p>Prisoner and ex-prisoner deaths identified through an independent search of the NCIS were compared with 'gold standard' records of prisoner and ex-prisoner deaths, generated from a national monitoring system and a state-based record linkage study, respectively. Of 294 known deaths in custody from 2001-2007, an independent search of the NCIS identified 229, giving a sensitivity of 77.9% (72.8%-82.3%). Of 677 known deaths among ex-prisoners from 2001-2007, an independent search of the NCIS identified 37, giving a sensitivity of 5.5% (4.0-7.4%). Ex-prisoner deaths that were detected were disproportionately drug-related, occurring within the first four weeks post-release, among younger prisoners and among those with more than two prior prison admissions.</p> <p>Conclusions</p> <p>Although a search of the NCIS detected the majority of reportable deaths among prisoners, it was only able to detect a small minority of reportable deaths among ex-prisoners. This suggests that the NCIS is not effective for monitoring mortality among ex-prisoners in Australia. Given the elevated rates of mortality among ex-prisoners in Australia and elsewhere, there remains an urgent need to establish a process for routine monitoring of ex-prisoner mortality, preferably through record linkage.</p

Patterns of Non-injection Drug Use Associated with Injection Cessation among Street-Involved Youth in Vancouver, Canada

Although abstinence from drug use is often a key goal of youth substance use treatment, transitioning to less harmful routes and types of drug use is desirable from both a clinical and public health perspective. Despite this, little is known about the trajectories of youth who inject drugs including changes in patterns of non-injection drug use. The At-Risk Youth Study (ARYS) is a longitudinal cohort of street-involved youth who use drugs in Vancouver, Canada. We used linear growth curve modeling to compare changes in non-injection drug use among participants who ceased injecting drugs for at least one 6-month period between September 2005 and May 2015 to matched controls who continued injecting over the same period. Of 387 eligible participants, 173 (44.7%) reported ceasing drug injection at least once. Non-injection drug use occurred during 160 (79.6%) periods of injection cessation. In adjusted linear growth curve analyses, the only non-injection drug use pattern observed to decrease significantly more than controls following injection cessation was daily crack/cocaine use (p&thinsp;=&thinsp;0.024). With the exception of frequent crack/cocaine use, transitions out of injection drug use did not appear to coincide with increased reductions in patterns of non-injection drug use. Our findings indicate that most (80%) of the observed injection cessation events occurred in the context of ongoing substance use. Given that transitioning out of drug injection represents a significant reduction in risk and harm, efforts supporting vulnerable youth to move away from injecting may benefit from approaches that allow for ongoing non-injection drug use. &nbsp

A comprehensive overview of radioguided surgery using gamma detection probe technology

The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology

Exploring methods to investigate sentencing decisions.

The determinants of sentencing are of much interest in criminal justice and legal research. Understanding the determinants of sentencing decisions is important for ensuring transparent, consistent, and justifiable sentencing practice that adheres to the goals of sentencing, such as the punishment, rehabilitation, deterrence, and incapacitation of the offender, as well as reparation for the victim. It is important to frame research questions on sentencing that can feasibly be answered by appropriate research methods, within the constraints of limited time and resources. For illustration, this article presents three methodological approaches for investigating the factors that may influence sentencing decisions: multilevel analysis using existing sentencing data; sampling of, and data collection from, sentenced court case files; and experimental designs involving sentencers deciding on hypothetical cases. The strengths and weaknesses of each approach are compared and discussed

A record linkage study of hospital episodes for drug treatment clients in Scotland, 1996-2006

Despite drug users’ high mortality rates, their contacts with hospital and psychiatric treatment have received comparatively little quantification. We provide a comprehensive summary and characterisation of the hospital and psychiatric treatment episodes of a national cohort of drug treatment clients during 1996–2006. Drug treatment records were linked to national registers of deaths, hepatitis C virus (HCV) diagnoses and hospital and psychiatric episodes (hereafter hospital episode). Allowing for overdispersion, we calculated hospital episode rates (HERs) by main diagnosis at discharge; standardised hospital episode ratios (SHERs) during 2001/2002 to 2005/2006 only and Cox regression analyses of time-to-hospital-episode. The Scottish Drug Misuse Database (SDMD) cohort comprised 69,457 individuals and 350,317 person-years (pys) with 107,723 hospital episodes by 27,124 individuals: 70,094 hospital episodes occurred during 229,504 pys in 2001/2002 to 2005/2006. The five discharge-diagnoses with highest SHERs were: mental and behavioural disorders 40.3 (95% CI: 38.6–42.1), circulatory system disease 3.7 (3.5–4.0), infectious and parasitic diseases 3.7 (3.4–4.0), diseases of the skin and subcutaneous tissue 3.5 (3.4–3.7), injury, poisoning and other consequences of external causes 3.4 (3.3–3.5). HCV-diagnosed clients were at over twofold greater risk of hospital episode (hazard ratio (HR), for those without diagnosis, 0.41, 95% CI: 0.39–0.43) and alcohol misuse increased risk (HR: 1.69, 95% CI: 1.60–1.80). HERs and SHERs align with SDMD clients’ cause-specific mortality pattern. Interventions for drug treatment clients might incorporate preventive strategies to address the significantly elevated diagnosis-specific SHERs – in particular, dual diagnoses with mental illnes