6,312 research outputs found
Hear My Voice: The Experiences of Transgender Sex-workers within the British Columbia Healthcare System
The purpose of this research project is to document the personal experiences of transgender sex workers (TSW) in dealing with the healthcare system. Healthcare professionals (HCP) exposure to sex workers or transgender people is limited, and often when exposed to this population, HCPs do not know the proper way to behave. This can lead to TSWs not feeling safe to access healthcare, which can have adverse health outcomes for them. Grounded in phenomenology and thematic analysis, phase one of this research involved collecting data through interviews with TSWs to explore the positive and negative experiences they have had with respect to their involvement in healthcare. During phase two of the research, a thematic analysis will be conducted focusing on a series of themes that were identified through interviews with TSWs, and any gaps or barriers to TSW care will be explored. The conclusions drawn from the research will provide a foundation for recommendations and suggestions to be made on how HCPs can help to provide a safe, supportive health care environment for TSWs. This will foster a better understanding of this unique population, and assist in equipping HCPs with the knowledge they need to provide competent care
Fuels treatment and wildfire effects on runoff from Sierra Nevada mixed-conifer forests
We applied an eco-hydrologic model (Regional Hydro-Ecologic Simulation System [RHESSys]), constrained with spatially distributed field measurements, to assess the impacts of forest-fuel treatments and wildfire on hydrologic fluxes in two Sierra Nevada firesheds. Strategically placed fuels treatments were implemented during 2011–2012 in the upper American River in the central Sierra Nevada (43 km2) and in the upper Fresno River in the southern Sierra Nevada (24 km2). This study used the measured vegetation changes from mechanical treatments and modelled vegetation change from wildfire to determine impacts on the water balance. The well-constrained headwater model was transferred to larger catchments based on geologic and hydrologic similarities. Fuels treatments covered 18% of the American and 29% of the Lewis catchment. Averaged over the entire catchment, treatments in the wetter central Sierra Nevada resulted in a relatively light vegetation decrease (8%), leading to a 12% runoff increase, averaged over wet and dry years. Wildfire with and without forest treatments reduced vegetation by 38% and 50% and increased runoff by 55% and 67%, respectively. Treatments in the drier southern Sierra Nevada also reduced the spatially averaged vegetation by 8%, but the runoff response was limited to an increase of less than 3% compared with no treatment. Wildfire following treatments reduced vegetation by 40%, increasing runoff by 13%. Changes to catchment-scale water-balance simulations were more sensitive to canopy cover than to leaf area index, indicating that the pattern as well as amount of vegetation treatment is important to hydrologic response
The Assembly of Diversity in the Morphologies and Stellar Populations of High-Redshift Galaxies
We have studied the evolution in the morphologies, sizes, stellar-masses,
colors, and internal color dispersion (ICD) of galaxies at z=1 and 2.3, using a
near-IR, flux-limited catalog for the HDF-N. At z=1 most luminous galaxies have
morphologies of early-to-mid Hubble-types, and many show transformations
between their rest-frame UV-optical morphologies. Galaxies at z=2.3 have
compact and irregular morphologies with no clearly evident Hubble-sequence
candidates. The mean galaxy size grows from z=2.3 to 1 by 40%, and the density
of galaxies larger than 3 kpc increases by 7 times. At z=1, the size-luminosity
distribution is broadly consistent with that of local galaxies, with passive
evolution. However, galaxies at z=2.3 are smaller than the large present-day
galaxies, and must continue to grow in size and stellar mass. We have measured
the galaxies' UV-optical ICD, which quantifies differences in morphology and
the relative amount of on-going star-formation. The mean and scatter in
galaxies' total colors and ICD increase from z=2.3 to 1. At z=1 many galaxies
with large ICD are spirals, with a few irregular systems. Few z=2.3 galaxies
have high ICD, and those that do are actively merging. We interpret this as
evidence for the presence of older and more diverse stellar populations at z=1
that are not generally present at z>2. We conclude that the star-formation
histories of galaxies at z>2 are dominated by discrete, recurrent bursts, which
quickly homogenize the galaxies' stellar content, and are possibly associated
with mergers. The increase in the stellar-population diversification by z<1.4
implies that merger-induced starbursts occur less frequently than at higher
redshifts, and more quiescent star-forming modes dominate. This transition
coincides with the emergence of Hubble-sequence galaxies. [Abridged]Comment: Accepted for publication in the Astrophysical Journal. 20 pages, in
emulateapj forma
Orbital, precessional and flaring variability of Cygnus X-1
We present the results of a 2.5-year multiwavelength monitoring programme of
Cygnus X-1, making use of hard and soft X-ray data, optical spectroscopy,
UBVJHK photometry and radio data. In particular we confirm that the 5.6-day
orbital period is apparent in all wavebands and note the existence of a
wavelength-dependence to the modulation, in the sense that higher energies
reach minimum first. We also find a strong modulation at a period of 142 +/- 7
days, which we suggest is due to precession and/or radiative warping of the
accretion disc. Strong modulation of the hard and soft X-ray flux at this long
period may not be compatible with simple models of an optically thin accretion
flow and corona in the low state. We present the basic components required for
more detailed future modelling of the system - including a partially optically
thick jet, quasi-continuous in the low state, the base of which acts as the
Comptonising corona. In addition, we find that there are a number of flares
which appear to be correlated in at least two wavebands and generally in more.
We choose two of these flares to study in further detail and find that the hard
and soft X-rays are well-correlated in the first and that the soft X-rays and
radio are correlated in the second. In general, the optical and infrared show
similar behaviour to each other but are not correlated with the X-rays or
radio.Comment: Accepted for publication in MNRAS, 2 figures in colou
Dust Emission from Active Galactic Nuclei
Unified schemes of active galactic nuclei (AGN) require an obscuring dusty
torus around the central source, giving rise to Seyfert 1 line spectrum for
pole-on viewing and Seyfert 2 characteristics in edge-on sources. Although the
observed IR is in broad agreement with this scheme, the behavior of the 10
micron silicate feature and the width of the far-IR emission peak remained
serious problems in all previous modeling efforts. We show that these problems
find a natural explanation if the dust is contained in about 5-10 clouds along
radial rays through the torus. The spectral energy distributions (SED) of both
type 1 and type 2 sources are properly reproduced from different viewpoints of
the same object if the visual optical depth of each cloud is larger than about
60 and the clouds' mean free path increases roughly in proportion to radial
distance.Comment: 11 pages, submitted to ApJ Letter
Infrared images of reflection nebulae and Orion's bar: Fluorescent molecular hydrogen and the 3.3 micron feature
Images were obtained of the (fluorescent) molecular hydrogen 1-0 S(1) line, and of the 3.3 micron emission feature, in Orion's Bar and three reflection nebulae. The emission from these species appears to come from the same spatial locations in all sources observed. This suggests that the 3.3 micron feature is excited by the same energetic UV-photons which cause the molecular hydrogen to fluoresce
Effects of magnetic field and disorder on electronic properties of Carbon Nanotubes
Electronic properties of metallic and semiconducting carbon nanotubes are
investigated in presence of magnetic field perpendicular to the CN-axis, and
disorder introduced through energy site randomness. The magnetic field field is
shown to induce a metal-insulator transition (MIT) in absence of disorder, and
surprisingly disorder does not affect significantly the MIT. These results may
find confirmation through tunneling experimentsComment: 4 pages, 6 figures. Phys. Rev. B (in press
Twisted partition functions for ADE boundary conformal field theories and Ocneanu algebras of quantum symmetries
For every ADE Dynkin diagram, we give a realization, in terms of usual fusion
algebras (graph algebras), of the algebra of quantum symmetries described by
the associated Ocneanu graph. We give explicitly, in each case, the list of the
corresponding twisted partition functionsComment: 47 pages, 25 figures and 17 tables. Several typos are corrected.
References adde
Electronic transport properties of quasicrystals: a Review
We present a review of some results concerning electronic transport
properties of quasicrystals. After a short introduction to the basic concepts
of quasiperiodicity, we consider the experimental transport properties of
electrical conductivity with particular focus on the effect of temperature,
magnetic field and defects. Then, we present some heuristic approaches that
tend to give a coherent view of different, and to some extent complementary,
transport mechanisms in quasicrystals. Numerical results are also presented and
in particular the evaluation of the linear response Kubo-Greenwood formula of
conductivity in quasiperiodic systems in presence of disorder.Comment: Latex, 28 pages, Journ. of Math. Phys., Vol38 April 199
Aplikasi Rekayasa Mutu Untuk Mengurangi Cacat Pada Mesin Injection Molding
The imperfect combustion process will be a problem in the development effort of diesel engine's performance. Nonhomogen air-fuel mixing process is one of the factors which cause the imperfect combustion.
By heating up the diesel fuel up to a certain temperature before it goes through the high pressure injection pump will lower its density and viscosity. Therefore, when injected in the combustion chamber, it will formed smaller droplets of fuel spray which result in a more homogenious air-fuel mixture. Also by using higher temperature will make the diesel fuel easier to ignite in order to compensate the limited time which is available in high speed operating conditions.
Diesel fuel heating can improve the combustion process to increase the power and decrease the fuel consumption optimally
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