Cloud fluid models of gas dynamics and star formation in galaxies

The large dynamic range of star formation in galaxies, and the apparently complex environmental influences involved in triggering or suppressing star formation, challenges the understanding. The key to this understanding may be the detailed study of simple physical models for the dominant nonlinear interactions in interstellar cloud systems. One such model is described, a generalized Oort model cloud fluid, and two simple applications of it are explored. The first of these is the relaxation of an isolated volume of cloud fluid following a disturbance. Though very idealized, this closed box study suggests a physical mechanism for starbursts, which is based on the approximate commensurability of massive cloud lifetimes and cloud collisional growth times. The second application is to the modeling of colliding ring galaxies. In this case, the driving processes operating on a dynamical timescale interact with the local cloud processes operating on the above timescale. The results is a variety of interesting nonequilibrium behaviors, including spatial variations of star formation that do not depend monotonically on gas density

Compression of Atomic Phase Space Using an Asymmetric One-Way Barrier

We show how to construct asymmetric optical barriers for atoms. These barriers can be used to compress phase space of a sample by creating a confined region in space where atoms can accumulate with heating at the single photon recoil level. We illustrate our method with a simple two-level model and then show how it can be applied to more realistic multi-level atoms

A novel tissue inhibitor of metalloproteinases-3 mutation reveals a common molecular phenotype in sorsby's fundus dystrophy

Sorsby’s fundus dystrophy (SFD) is a dominantly inherited degenerative disease of the retina that leads to loss of vision in middle age. It has been shown to be caused by mutations in the gene for tissue inhibitor of metalloproteinases-3 (TIMP-3). Five different mutations have previously been identified, all introducing an extra cysteine residue into exon 5 (which forms part of the C-terminal domain) of the TIMP-3 molecule; however, the significance of these mutations to the disease phenotype was unknown. In this report, we describe the expression of several of these mutated genes, together with a previously unreported novel TIMP-3 mutation from a family with SFD that results in truncation of most of the C-terminal domain of the molecule. Despite these differences, all of these molecules are expressed and exhibit characteristics of the normal protein, including inhibition of metalloproteinases and binding to the extracellular matrix. However, unlike wild-type TIMP-3, they all form dimers. These observations, together with the recent finding that expression of TIMP-3 is increased, rather than decreased, in eyes from patients with SFD, provides compelling evidence that dimerized TIMP-3 plays an active role in the disease process by accumulating in the eye. Increased expression of TIMP-3 is also observed in other degenerative retinal diseases, including the more severe forms of agerelated macular degeneration, the most common cause of blindness in the elderly in developed countries. We hypothesize that overexpression of TIMP-3 may prove to be a critical step in the progression of a variety of degenerative retinopathies

Season-long changes in the body composition profiles of competitive female Rugby Union players assessed via dual energy x-ray absorptiometry

Background: Reference data for the body composition values of female athletes are limited to very few sports, with female Rugby Union players having mostly been omitted from such analyses. Methods: Using dual energy X-ray absorptiometry (DXA) scans, this study assessed the body composition profiles (body mass, bone mineral content; BMC, fat mass; FM, lean mass; LM, bone mineral density; BMD) of 15 competitive female Rugby Union players before and after the 2018/19 competitive season. Total competitive match-play minutes were also recorded for each player. Results: Body mass (73.7±9.6 kg vs 74.9±10.2 kg, p≤0.05, d=0.13) and BMC (3.2±0.4 kg vs 3.3±0.4 kg, p≤0.05, d=0.15) increased pre- to post-season for all players. Conversely, FM (21.0±8.8 kg), LM (50.7±3.9 kg), and BMD (1.31±0.06 g·cm-2) were similar between time-points (all p>0.05). Accounting for position, body mass (rpartial(12) = 0.196), FM (rpartial(12) = -0.013), LM (rpartial(12) = 0.351), BMD (rpartial(12) = 0.168) and BMC (rpartial(12) = -0.204) showed no correlation (all p>0.05) against match-play minutes. Conclusion: The demands of the competitive season influenced specific body composition indices (i.e., body mass, BMC) in female Rugby Union players; a finding which was unrelated to the number of minutes played in matches. While the causes of such differences remain unclear, practitioners should be cognisant of the body composition changes occurring throughout a female Rugby Union competitive season and, where necessary, consider modifying variables associated with adaptation and recovery accordingly

Particle size segregation in granular flow in silos

Segregation and layering of alumina in storage silos are investigated, with a view to predicting output quality versus time, given known variations in input quality on emplacement. A variety of experiments were conducted, existing relevant publications were reviewed, and the basis for an algorithm for predicting the effect of withdrawing from a central flowing region, in combination with variations in quality due to geometric, layering and segregation effects, is described in this report

Tuberculous dactylitis—an easily missed diagnosis

The prevalence of tuberculosis (TB) continues to rise worldwide. Current migration patterns and increased travel to high-prevalence TB countries will result in more frequent presentations of less common forms of TB. Tuberculous dactylitis, a form of tuberculous osteomyelitis, is well recognised in countries with a high prevalence of TB. We provide a systematic review of all published cases of tuberculous dactylitis in children and adolescents and describe a case to illustrate the typical features of the disease. Our review revealed 37 cases of tuberculous dactylitis in children and adolescents, all reported in the last 17years. Children less than 10 years of age are most frequently affected and the hand is the most commonly affected site. Concurrent pulmonary TB is present in a fifth of cases and systemic symptoms are usually absent. Positive TST and IGRA support the presumptive diagnosis, but cannot be used as rule-out tests. The definitive diagnosis relies on the detection M. tuberculosis by PCR or culture. Treatment should comprise of a standard three to four drug anti-tuberculous regimen. The optimal treatment duration remains unknown. Surgery has a limited role in the treatment in general but may play a supportive role, and curettage of the cavity has been recommended for avascular lesion

Radiocarbon dating results from the Beaker People Project, 2007: Scottish samples

The Beaker People Project is a major interdisciplinary five-year research programme, funded by the Arts and Humanities Research Council and led by one of the authors (Mike Parker Pearson of Sheffield University). It aims to investigate patterns of diet, mobility and health in British Beaker-associated skeletons (and in contemporaneous non-Beaker associated skeletons) to help address long-standing issues of identity, such as: are the people who were buried with Beaker pottery any different from their contemporaries who were not? Are possible immigrants identifiable, as was the case with the Amesbury Archer? The Project will investigate 250 sets of remains, from five geochemically-contrasting areas – namely eastern Scotland, Yorkshire, the Peak District, Wessex and Wales – using osteology, dental microwear, histology and pathology, and isotopic analysis of tooth enamel and bone (with carbon and nitrogen in bone providing information about diet, strontium and oxygen in tooth enamel providing information about mobility, and sulphur in bone providing information about coastal vs. non-coastal residence). A subset of the 250 individuals is to be radiocarbon-dated, to improve our understanding of Beaker chronology

Realistic Exact Solution for the Exterior Field of a Rotating Neutron Star

A new six-parametric, axisymmetric and asymptotically flat exact solution of Einstein-Maxwell field equations having reflection symmetry is presented. It has arbitrary physical parameters of mass, angular momentum, mass--quadrupole moment, current octupole moment, electric charge and magnetic dipole, so it can represent the exterior field of a rotating, deformed, magnetized and charged object; some properties of the closed-form analytic solution such as its multipolar structure, electromagnetic fields and singularities are also presented. In the vacuum case, this analytic solution is matched to some numerical interior solutions representing neutron stars, calculated by Berti & Stergioulas (Mon. Not. Roy. Astron. Soc. 350, 1416 (2004)), imposing that the multipole moments be the same. As an independent test of accuracy of the solution to describe exterior fields of neutron stars, we present an extensive comparison of the radii of innermost stable circular orbits (ISCOs) obtained from Berti & Stergioulas numerical solutions, Kerr solution (Phys. Rev. Lett. 11, 237 (1963)), Hartle & Thorne solution (Ap. J. 153, 807, (1968)), an analytic series expansion derived by Shibata & Sasaki (Phys. Rev. D. 58 104011 (1998)) and, our exact solution. We found that radii of ISCOs from our solution fits better than others with realistic numerical interior solutions.Comment: 13 pages, 13 figures, LaTeX documen