4,332 research outputs found
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A systematic review of lesbian, gay, bisexual and transgender health in the West Midlands region of the UK compared to published UK research
It is estimated that approximately 3-8% of the UK population identify as lesbian, gay, bisexual or trans (LGBT). Until now, most health research on gay and bisexual men has been around HIV, AIDS and sexually transmitted diseases and for trans people has been on the transitioning process only. However, it has been apparent to the LGBT community that that there are a wide variety of other physical and mental health issues that are also important and that the proportion of gay and bisexual men who have HIV/AIDS is relatively small. Very little general LGBT health research has been published so far and there are very few health services that specifically address the general health concerns of the LGBT community. This systematic review presents all available research conducted in the West Midlands on LGBT health since 2000. Local health research is compared to UK national, peer reviewed and published LGBT health research in order to determine whether the local results are unusual compared to national LGBT data, and to routinely collected data on the UK population, where appropriate, in order to determine whether and where the LGBT population differ from the general population. Only UK research has been included because there was no previous UK specific
systematic review so it was unclear how generalisable foreign research would be to the UK
Boundary conditions for the numerical solution of elliptic equations in exterior regions
Elliptic equations in exterior regions frequently require a boundary condition at infinity to ensure the well-posedness of the problem. Examples of practical applications include the Helmholtz equation and Laplace's equation. Computational procedures based on a direct discretization of the elliptic problem require the replacement of the condition on a finite artificial surface. Direct imposition of the condition at infinity along the finite boundary results in large errors. A sequence of boundary conditions is developed which provides increasingly accurate approximations to the problem in the infinite domain. Estimates of the error due to the finite boundary are obtained for several cases. Computations are presented which demonstrate the increased accuracy that can be obtained by the use of the higher order boundary conditions. The examples are based on a finite element formulation but finite difference methods can also be used
An adaptive pseudo-spectral method for reaction diffusion problems
The spectral interpolation error was considered for both the Chebyshev pseudo-spectral and Galerkin approximations. A family of functionals I sub r (u), with the property that the maximum norm of the error is bounded by I sub r (u)/J sub r, where r is an integer and J is the degree of the polynomial approximation, was developed. These functionals are used in the adaptive procedure whereby the problem is dynamically transformed to minimize I sub r (u). The number of collocation points is then chosen to maintain a prescribed error bound. The method is illustrated by various examples from combustion problems in one and two dimensions
Feeding the fire: Tracing the mass-loading of 10^7 K galactic outflows with O VI absorption
Galactic outflows regulate the amount of gas galaxies convert into stars.
However, it is difficult to measure the mass outflows remove because they span
a large range of temperatures and phases. Here, we study the rest-frame
ultraviolet spectrum of a lensed galaxy at z~2.9 with prominent interstellar
absorption lines from O I, tracing neutral gas, up to O VI, tracing
transitional phase gas. The O VI profile mimics weak low-ionization profiles at
low velocities, and strong saturated profiles at high velocities. These trends
indicate that O VI gas is co-spatial with the low-ionization gas. Further, at
velocities blueward of -200 km/s the column density of the low-ionization
outflow rapidly drops while the O VI column density rises, suggesting that O VI
is created as the low-ionization gas is destroyed. Photoionization models do
not reproduce the observed O VI, but adequately match the low-ionization gas,
indicating that the phases have different formation mechanisms. Photoionized
outflows are more massive than O VI outflows for most of the observed
velocities, although the O VI mass outflow rate exceeds the photoionized
outflow at velocities above the galaxy's escape velocity. Therefore, most gas
capable of escaping the galaxy is in a hot outflow phase. We suggest that the O
VI absorption is a temporary by-product of conduction transferring mass from
the photoionized phase to an unobserved hot wind, and discuss how this
mass-loading impacts the observed circum-galactic medium.Comment: 17 pages, 12 figures, accepted for publication in MNRA
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EXOGEN ultrasound bone healing system for long bone fractures with non-union or delayed healing
Boundary layer transition
The boundary layer stability, its active control by sound and surface heating and the effect of curvature are studied numerically and experimentally for subsonic flow. In addition, the experimental and flight test data are correlated using the stability theory for supersonic Mach numbers. Active transition fixing and feedback control of boundary layer by sound interactions are experimentally investigated at low speed over an airfoil. Numerical simulation of active control by surface heating and cooling in air shows that by appropriate phase adjustment a reduction in the level of perturbation can be obtained. This simulation is based on the solution of two-dimensional compressible Navier-Stokes equations for a flat plate. Goertler vortices are studied experimentally on an airfoil in the Low Turbulence Pressure Tunnel (LTPT). The flow pattern was visualized using the sublimating chemical technique and data were obtained using a three component laser velocimeter. The effect of curvature on swept leading-edge stability on a cylinder was numerically studied. The results suggest that transition is dominated by traveling disturbance waves and that the waves with the greatest total amplification has an amplitude ratio of e sup 11. Experimental data from the quiet supersonic tunnel and flight tests are analyzed using linear compressible stability theory
Time Delay Measurements for the Cluster-lensed Sextuple Quasar SDSS J2222+2745
We report first results from an ongoing monitoring campaign to measure time
delays between the six images of the quasar SDSS\,J22222745, gravitationally
lensed by a galaxy cluster. The time delay between A and B, the two most highly
magnified images, is measured to be days (95\%
confidence interval), consistent with previous model predictions for this lens
system. The strong intrinsic variability of the quasar also allows us to derive
a time delay value of days between image C and A,
in spite of modest overlap between their light curves in the current data set.
Image C, which is predicted to lead all the other lensed quasar images, has
undergone a sharp, monotonic flux increase of 60-75\% during 2014. A
corresponding brightening is firmly predicted to occur in images A and B during
2016. The amplitude of this rise indicates that time delays involving all six
known images in this system, including those of the demagnified central images
D-F, will be obtainable from further ground-based monitoring of this system
during the next few years.Comment: 9 pages, 9 figures, Version accepted for publication in Ap
On the lack of correlation between Mg II 2796, 2803 Angstrom and Lyman alpha emission in lensed star-forming galaxies
We examine the Mg II 2796, 2803 Angstrom, Lyman alpha, and nebular line
emission in five bright star-forming galaxies at 1.66<z<1.91 that have been
gravitationally lensed by foreground galaxy clusters. All five galaxies show
prominent Mg II emission and absorption in a P Cygni profile. We find no
correlation between the equivalent widths of Mg II and Lyman alpha emission.
The Mg II emission has a broader range of velocities than do the nebular
emission line profiles; the Mg II emission is redshifted with respect to
systemic by 100 to 200 km/s. When present, Lyman alpha is even more redshifted.
The reddest components of Mg II and Lyman alpha emission have tails to 500-600
km/s, implying a strong outflow. The lack of correlation in the Mg II and Lyman
alpha equivalent widths, the differing velocity profiles, and the high ratios
of Mg II to nebular line fluxes together suggest that the bulk of Mg II
emission does not ultimately arise as nebular line emission, but may instead be
reprocessed stellar continuum emission.Comment: The Astrophysical Journal, in press. 6 pages, 2 figure
Indigenous participation in monitoring megafauna within the Reef 2050 Integrated Monitoring and Reporting Program: final report of the Indigenous participation team in the megafauna expert group
[Extract] This report summarises a desktop review and analysis of Indigenous participation in monitoring megafauna in the coastal waters of the Great Barrier Reef (the Reef), and contributes to the development of design recommendations that satisfy the objectives of the Reef 2050 Integrated Monitoring and Reporting Program (RIMReP). The review commences with an overview of Traditional Owner groups in the Reef that have strong cultural connections to megafauna, particularly sea turtles and dugongs, and highlights their aspiration to participate in RIMReP comprising an inseparable component of the Reef 2050 Long-Term Sustainability Plan (Reef 2050 Plan). About 20 per cent (9/44) of Traditional Owner groups in the Reef were identified as participating in megafauna monitoring activities, mostly through ranger programs. However, apart from detailed reports of dolphin and dugong boat surveys undertaken by James Cook University (JCU) in partnership with five north Queensland Traditional Owner groups, representing 11 per cent of Traditional Owner groups in the Reef, we found no other documentation. Hence, our assessment should be treated with caution given the limitations of using information collated only from a desktop review. Nevertheless, the apparent absence of broad participation in megafauna monitoring activities provides an opportunity to implement a coordinated and standardised approach throughout the Reef from the outset as reflected in our recommendations
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