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Severity of Visual Field Loss at First Presentation to Glaucoma Clinics in England and Tanzania
Purpose: To compare severity of visual field (VF) loss at first presentation in glaucoma clinics in England and Tanzania.
Methods: Large archives of VF records from automated perimetry were used to retrospectively examine vision loss at first presentation in glaucoma clinics in Tanzania (N = 1,502) and England (N = 9,264). Mean deviation (MD) of the worse eye at the first hospital visit was used as an estimate of detectable VF loss severity.
Results: In Tanzania, 44.7% {CI95%: 42.2, 47.2} of patients presented with severe VF loss (< −20 dB), versus 4.6% {4.1, 5.0} in England. If we consider late presentation to also include cases of advanced loss (-12.01 dB to -20 dB), then the proportion of patients presenting late was 58.1% {55.6, 60.6} and 14.0% {13.3, 14.7}, respectively. The proportion of late presentations was greater in Tanzania at all ages, but the difference was particularly pronounced among working-age adults, with 50.3% {46.9, 53.7} of 18–65-year-olds presenting with advanced or severe VF loss, versus 10.2% {9.3, 11.3} in England. In both countries, men were more likely to present late than women.
Conclusions: Late presentation of glaucoma is a problem in England, and an even greater challenge in Tanzania. Possible solutions are discussed, including increased community eye-care, and a more proactive approach to case finding through the use of disruptive new technologies, such as low-cost, portable diagnostic aids
Characteristics of First-Order Vortex Lattice Melting: Jumps in Entropy and Magnetization
We derive expressions for the jumps in entropy and magnetization
characterizing the first-order melting transition of a flux line lattice. In
our analysis we account for the temperature dependence of the Landau parameters
and make use of the proper shape of the melting line as determined by the
relative importance of electromagnetic and Josephson interactions. The results
agree well with experiments on anisotropic YBaCuO and
layered BiSrCaCuO materials and reaffirm the validity of
the London model.Comment: 4 pages. We have restructured the paper to emphasize that in the
London scaling regime (appropriate for YBCO) our results are essentially
exact. We have also emphasized that a major controversy over the relevance of
the London model to describe VL melting has been settled by this wor
Flow fluctuations and long-range correlations: elliptic flow and beyond
These proceedings consist of a brief overview of the current understanding of
collective behavior in relativistic heavy-ion collisions. In particular, recent
progress in understanding the implications of event-by-event fluctuations have
solved important puzzles in existing data -- the "ridge" and "shoulder"
phenomena of long-range two-particle correlations -- and have created an
exciting opportunity to tightly constrain theoretical models with many new
observables.Comment: 10 pages, 2 figures, Proceedings for the 22nd International
Conference On Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter
2011), Annecy, France, May 23 - 28, 2011; includes Fig. 2 which was omitted
from journal submission for lack of spac
The far-infrared energy distributions of Seyfert and starburst galaxies in the Local Universe: ISO photometry of the 12 micron active galaxy sample
New far-infrared photometry with ISOPHOT, onboard the Infrared Space
Observatory, is presented for 58 galaxies with homogeneous published data for
another 32 galaxies all belonging to the 12 micron galaxy sample. In total 29
Seyfert 1's, 35 Seyfert 2's and 12 starburst galaxies, about half of the 12
micron active galaxy sample, plus 14 normal galaxies for comparison. The ISO
and the IRAS data are used to define color-color diagrams and spectral energy
distributions (SED). Thermal dust emission at two temperatures (one cold at
15-30K and one warm at 50-70K) can fit the 60-200 micron SED, with a dust
emissivity law proportional to the inverse square of the wavelength. Seyfert
1's and Seyfert 2's are indistinguishable longward of 100 micron, while, as
already seen by IRAS, the former have flatter SEDs shortward of 60 micron. A
mild anti-correlation is found between the [200 - 100] color and the "60 micron
excess". We infer that this is due to the fact that galaxies with a strong
starburst component, and thus a strong 60 micron flux, have a steeper
far-infrared turnover. In non-Seyfert galaxies, increasing the luminosity
corresponds to increasing the star formation rate, that enhances the 25 and 60
micron emission. This shifts the peak emission from around 150 micron in the
most quiescent spirals to shorter than 60 micron in the strongest starburst
galaxies.Comment: Accepted for publication in The Astrophysical Journal AASTeX preprint
with 49 pages and 20 figures Also available at
http://orion.ifsi.rm.cnr.it/publ.htm
Gravitational collapse in 2+1 dimensional AdS spacetime
We present results of numerical simulations of the formation of black holes
from the gravitational collapse of a massless, minimally-coupled scalar field
in 2+1 dimensional, axially-symmetric, anti de-Sitter (AdS) spacetime. The
geometry exterior to the event horizon approaches the BTZ solution, showing no
evidence of scalar `hair'. To study the interior structure we implement a
variant of black-hole excision, which we call singularity excision. We find
that interior to the event horizon a strong, spacelike curvature singularity
develops. We study the critical behavior at the threshold of black hole
formation, and find a continuously self-similar solution and corresponding
mass-scaling exponent of approximately 1.2. The critical solution is universal
to within a phase that is related to the angle deficit of the spacetime.Comment: 31 pages, 20 figures, LaTeX. Replaced with version to be published in
Phys. Rev.
Inhomogeneous tachyon dynamics and the zipper
We study the process of inhomogeneous tachyon condensation in an intersecting
D1- and anti-D1-brane system using an effective tachyon DBI action. By
switching to the Hamiltonian formalism, we numerically solve for the dynamical
evolution of the system at a small intersection angle. We find that the decay
proceeds indefinitely and resembles the action of two zippers moving away from
the intersection point at the speed of light, zipping the branes together and
leaving inhomogeneous tachyon matter behind. We also discuss the range of
validity of our analysis and discuss the relation of the D1-anti-D1 description
of the system to one in terms of an intersecting D1-D1-brane pair.Comment: 23 pages, 12 figures. v2: added references; v3: more references,
published versio
Crossover Scaling in Dendritic Evolution at Low Undercooling
We examine scaling in two-dimensional simulations of dendritic growth at low
undercooling, as well as in three-dimensional pivalic acid dendrites grown on
NASA's USMP-4 Isothermal Dendritic Growth Experiment. We report new results on
self-similar evolution in both the experiments and simulations. We find that
the time dependent scaling of our low undercooling simulations displays a
cross-over scaling from a regime different than that characterizing Laplacian
growth to steady-state growth
Magazine and reader constructions of 'metrosexuality' and masculinity: a membership categorisation analysis
Since the launch of men's lifestyle magazines in the 1980s, academic literature has predominantly focused on them as a cultural phenomenon arising from entrepreneurial and commercial initiatives and/or as cultural texts that proffer representations of masculinity such as 'new lad' and 'new dad'. This paper steps aside from the focus on culture and, instead, treats magazine content as a discursive space in which gender and sexuality are oriented to, negotiated, and accomplished within and beyond the magazine itself (i.e. through readers' responses). Specifically, membership categorisation analysis is deployed to explore how the relatively new (and perhaps alternative) category for men - 'metrosexual' - is presented and received. Our analysis suggests that masculinity concerns are central in debates about 'metrosexuality', with self-identified 'metrosexuals' invoking heterosexual prowess and self-respect on the one hand, and critics (e.g. selfidentified 'real men') lamenting 'metrosexuality' for its perceived effeminacy and lack of authenticity on the other. Implications for understanding contemporary masculinities are discussed
Prehabilitative versus rehabilitative exercise in prostate cancer patients undergoing prostatectomy
Purpose: The study compared the efficacy of commencing supervised exercise in men with prostate cancer before and after prostatectomy on objective and patient-reported outcomes, hospital length of stay, and urinary incontinence. Methods: Forty-one men were randomised to a 6-week prehabilitation or rehabilitation exercise programme. Prehabilitation involved resistance and aerobic exercise thrice weekly pre-surgery, while rehabilitation comprised the same commencing 6-weeks post-surgery. Assessments included strength, function (chair rise, stair climb, 400-m, 6-m usual, fast, and backwards walk), body composition, fatigue and quality of life, undertaken at pre-surgery, early post-surgery and late post-surgery phase, with urinary incontinence (24-h pad test) assessed at 2, 6, and 12-weeks post-surgery. Intention-to-treat and sensitivity analyses were undertaken. Results: Of thirty-eight men (48–73 years), 29 completed all assessments with most undergoing robotic-assisted laparoscopic prostatectomy (92.1%). In the pre-surgery phase, prehabilitation improved muscle strength (leg press: 17.2 kg; chest press: 2.9 kg; p ≤ 0.001), 400-m, chair rise, 6-m fast and backward walk tests (p ≤ 0.001–0.028). Strength and function declines in the early post-surgery phase were maintained late post-surgery. Rehabilitation showed declines of these outcomes after surgery with improvement late post-surgery (leg press: 14.6 kg, p \u3c 0.001; chest press: 6.8 kg, p \u3c 0.001; 400-m walk: -12.0 s, p = 0.005), resulting in no difference between groups at 12 weeks. There were no significant differences between groups for patient-reported outcomes, hospital length of stay or urinary incontinence. Conclusion: Pre-surgical exercise enhanced strength and function, protecting against post-surgery declines. Although exercise post-surgery is beneficial for recouping strength and function, where possible men undergoing prostatectomy are encouraged to exercise pre-surgery. Trial registration: ACTRN12617001115325 registered 31 July 2017
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