Comparison of porcine thorax to gelatine blocks for wound

Published online first in International Journal of Legal Medicine. The support of EPSRC and The Home Office are recognised. Open Access, this article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http:/ /creativecommons.org/licenses/by/4.0/)Tissue simulants are typically used in ballistic testing as substitutes for biological tissues. Many simulants have been used, with gelatine amongst the most common. While two concentrations of gelatine (10 and 20 %) have been used extensively, no agreed standard exists for the preparation of either. Comparison of ballistic damage produced in both concentrations is lacking. The damage produced in gelatine is also questioned, with regards to what it would mean for specific areas of living tissue. The aim of the work discussed in this paper was to consider how damage caused by selected pistol and rifle ammunition varied in different simulants. Damage to gelatine blocks 10 and 20 % in concentration were tested with 9 mm Luger (9 × 19 full metal jacket; FMJ) rounds, while damage produced by .223 Remington (5.56 × 45 Federal Premium® Tactical® Bonded®) rounds to porcine thorax sections (skin, underlying tissue, ribs, lungs, ribs, underlying tissue, skin; backed by a block of 10 % gelatine) were compared to 10 and 20 % gelatine blocks. Results from the .223 Remington rifle round, which is one that typically expands on impact, revealed depths of penetration in the thorax arrangement were significantly different to 20 % gelatine, but not 10 % gelatine. The level of damage produced in the simulated thoraxes was smaller in scale to that witnessed in both gelatine concentrations,though greater debris was produced in the thoraxes.The support of EPSRC and The Home Office are recognised

Cerebellar Abiotrophy in Two Related Lion-tailed Macaques (Macaca silenus)

Cerebellar abiotrophy is a degenerative condition characterized by either early or late onset of severe neurological deficits caused by the marked depletion of Purkinje cells and granule cell neurons of the cerebellar cortex. The condition has been reported in numerous species with a proposed genetic basis of transmission. Here we present the anatomopathological investigation of two closely related lion-tailed macaques. Both cases, a 9-month-old male and a 4-month-old female, shared a long history of progressively worsening ataxia, incoordination and delayed body growth. Based on the characteristic findings, diagnoses of cerebellar abiotrophy were made. The relatedness of the two cases strongly supports an inherited mode of transmission. To the authors’ knowledge, this is the first report of cerebellar abiotrophy in a macaque species

Nuclear Black Hole Formation in Clumpy Galaxies at High Redshift

Massive stellar clumps in high redshift galaxies interact and migrate to the center to form a bulge and exponential disk in <1 Gyr. Here we consider the fate of intermediate mass black holes (BHs) that might form by massive-star coalescence in the dense young clusters of these disk clumps. We find that the BHs move inward with the clumps and reach the inner few hundred parsecs in only a few orbit times. There they could merge into a supermassive BH by dynamical friction. The ratio of BH mass to stellar mass in the disk clumps is approximately preserved in the final ratio of BH to bulge mass. Because this ratio for individual clusters has been estimated to be ~10^{-3}, the observed BH-to-bulge mass ratio results. We also obtain a relation between BH mass and bulge velocity dispersion that is compatible with observations of present-day galaxies.Comment: 10 pages, 3 figures, accepted by Ap

The protective performance of selected UK police body armor challenged by M75 grenades

UK Police ‘soft’ body armor is designed to provide protection from sharp-weapons and low-velocity pistol ammunition; if ‘hard’ armor plates are fitted then high-velocity rifle protection is provided. Several different levels of protection for both soft and hard armor are available and these are tailored to the individual police officers’ role. The level of protection offered by these types of armor from fragmentation threats is not known as fragmentation is not typically considered a threat to UK Police Officers. However, fragmentation from devices such as grenades may be a threat to certain specialized units and during terrorist incidents. In this work, neither the soft nor hard UK Police body armor (HG2 and RF1 respectively) investigated were perforated when challenged by M75 Yugoslavian grenades at a distance of 1 m from the point of detonation. The effect due to blast was not considered. The work has provided confidence regarding the performance of selected police body armor against fragmentation from a selected grenade threat

A preliminary study into injuries due to non-perforating ballistic impacts into soft body armour over the spine

The UK Home Office test method for ballistic protective police body armours considers anterior torso impacts to be the worst-case scenario and tests rear armour panels to the same standards as front panels. The aim of this paper was to examine the injuries from spinal behind armour blunt trauma (BABT) impacts. This study used a cadaveric 65 kg, female pig barrel and 9 mm Luger ammunition (9 × 19 mm, FMJ Nammo Lapur Oy) into HG1/A + KR1 soft armour panels over the spine. Injuries were inspected and sections removed for x-radiography and micro-CT assessment. All shots over the spine resulted in deep soft tissue injuries from pencilling of the armour and the shirt worn under the armour. The wounds had embedded fabric debris which would require surgery to remove resulting in increased recovery time over injuries usually seen in anterior torso BABT impacts, which are typically haematoma and fractured ribs. The shot with the deepest soft tissue wound (41 mm) also resulted in a fractured spinous process. Shots were also fired at the posterior and anterior rib area of the pig barrel, for comparison to the spine. Similar wounds were seen on the shots to the posterior rib area while shallower, smaller wounds were seen on the anterior and one anterior rib shot resulted in a single, un-displaced rib fracture. The anatomical differences between pigs and humans would most likely mean that injury to a human from these impacts would be more serious

Reconstructing the massive black hole cosmic history through gravitational waves

The massive black holes we observe in galaxies today are the natural end-product of a complex evolutionary path, in which black holes seeded in proto-galaxies at high redshift grow through cosmic history via a sequence of mergers and accretion episodes. Electromagnetic observations probe a small subset of the population of massive black holes (namely, those that are active or those that are very close to us), but planned space-based gravitational-wave observatories such as the Laser Interferometer Space Antenna (LISA) can measure the parameters of ``electromagnetically invisible'' massive black holes out to high redshift. In this paper we introduce a Bayesian framework to analyze the information that can be gathered from a set of such measurements. Our goal is to connect a set of massive black hole binary merger observations to the underlying model of massive black hole formation. In other words, given a set of observed massive black hole coalescences, we assess what information can be extracted about the underlying massive black hole population model. For concreteness we consider ten specific models of massive black hole formation, chosen to probe four important (and largely unconstrained) aspects of the input physics used in structure formation simulations: seed formation, metallicity ``feedback'', accretion efficiency and accretion geometry. For the first time we allow for the possibility of ``model mixing'', by drawing the observed population from some combination of the ``pure'' models that have been simulated. A Bayesian analysis allows us to recover a posterior probability distribution for the ``mixing parameters'' that characterize the fractions of each model represented in the observed distribution. Our work shows that LISA has enormous potential to probe the underlying physics of structure formation.Comment: 24 pages, 16 figures, submitted to Phys. Rev.

Direct cosmological simulations of the growth of black holes and galaxies

We investigate the coupled formation and evolution of galaxies and their embedded supermassive black holes using state-of-the-art hydrodynamic simulations of cosmological structure formation. For the first time, we self-consistently follow the dark matter dynamics, radiative gas cooling, star formation, as well as black hole growth and associated feedback processes, starting directly from initial conditions appropriate for the LambdaCDM cosmology. Our modeling of the black hole physics is based on an approach we have developed in simulations of isolated galaxy mergers. Here we examine: (i) the predicted global history of black hole mass assembly (ii) the evolution of the local black hole-host mass correlations and (iii) the conditions that allow rapid growth of the first quasars, and the properties of their hosts and descendants today. We find a total black hole mass density in good agreement with observational estimates. The black hole accretion rate density peaks at lower redshift and evolves more strongly at high redshift than the star formation rate density, but the ratio of black hole to stellar mass densities shows only a moderate evolution at low redshifts. We find strong correlations between black hole masses and properties of the stellar systems, agreeing well with the measured local M_BH-sigma and M_BH -M_* relationships, but also suggesting (dependent on the mass range) a weak evolution with redshift in the normalization and the slope. Our simulations also produce massive black holes at high redshift, due to extended periods of exponential growth in regions that collapse early and exhibit strong gas inflows. These first supermassive BH systems however are not necessarily the most massive ones today, since they are often overtaken in growth by quasars that form later. (abridged)Comment: 22 pages, 17 figures, submitted to Ap

Resolving Gas Dynamics in the Circumnuclear Region of a Disk Galaxy in a Cosmological Simulation

Using a hydrodynamic adaptive mesh refinement code, we simulate the growth and evolution of a galaxy, which could potentially host a supermassive black hole, within a cosmological volume. Reaching a dynamical range in excess of 10 million, the simulation follows the evolution of the gas structure from super-galactic scales all the way down to the outer edge of the accretion disk. Here, we focus on global instabilities in the self-gravitating, cold, turbulence-supported, molecular gas disk at the center of the model galaxy, which provide a natural mechanism for angular momentum transport down to sub-pc scales. The gas density profile follows a power-law scaling as r^-8/3, consistent with an analytic description of turbulence in a quasi-stationary circumnuclear disk. We analyze the properties of the disk which contribute to the instabilities, and investigate the significance of instability for the galaxy's evolution and the growth of a supermassive black hole at the center.Comment: 16 pages (includes appendix), submitted to ApJ. Figures here are at low resolution; for higher resolution version, download http://casa.colorado.edu/~levinerd/ms.pd

Drinking in the dark: shedding light on young people’s alcohol consumption experiences

This paper draws on 12 months of ethnographic research to explore the drinking experiences of young people, aged 15-24, living in the suburban case study locations of Chorlton and Wythenshawe, Manchester, UK. This paper moves beyond the contemporary geographical imaginary of alcohol consumption as a city-centre issue, to explore suburban indoor and outdoor drinking cultures. Through paying attention to atmospheres of darkness and lightness, I show how drinkscapes are active constituents of young people’s drinking occasions, rather than passive backdrops. More than this, I illustrate how young people transform dark and light drinkscapes, thereby shaping the drinking practices of themselves and others. Through looking at the interplay between the curating of an atmosphere, and the experience of that atmosphere when bodies, and practices are inserted into it, this paper offers a different take on the ‘drinking at home is bad, drinking in public spaces is good’ argument, with original policy suggestions