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Point-of-care cryptococcal antigen screening - a case-control diagnostic accuracy study of the immuno-mycologics cryptococcal antigen lateral flow assay for screening finger-prick blood and urine among asymptomatic HIV-infected adults
HIV-Associated Cryptococcal Meningitis: Bridging the Gap Between Developed and Resource-Limited Settings.
Cryptococcal meningitis is a major cause of HIV-associated morbidity and mortality worldwide. Most cases occur in low-income countries, where over half of patients die within 10 weeks of diagnosis compared to as few as 10 % of patients from developed countries. A host of factors, spanning the HIV care continuum, are responsible for this gap in treatment outcomes between developed and resource-limited settings. We explore factors responsible for this outcomes gap and describe low-cost, highly effective measures that can be implemented immediately to improve outcomes in resource-limited settings. We also explore health-system challenges that must be addressed to reduce mortality further, recent research in disease prevention, and novel short-course treatment regimens that, if efficacious, could be implemented in resource-limited settings where the cost of standard treatment regimens is currently prohibitive
Spatially Extended Low Ionization Emission Regions (LIERs) at
We present spatially resolved emission diagnostics for eight
galaxies that demonstrate extended low ionization emission-line regions (LIERs)
over kpc scales. Eight candidates are selected based on their spatial extent
and emission line fluxes from slitless spectroscopic observations with the
HST/WFC3 G141 and G800L grisms in the well-studied GOODS survey fields. Five of
the candidates (62.5%) are matched to X-ray counterparts in the \textit{Chandra
X-Ray Observatory} Deep Fields. We modify the traditional
Baldwin-Philips-Terlevich (BPT) emission line diagnostic diagram to use
[SII]/(H+[NII]) instead of [NII]/H to overcome the blending of
[NII] and H+[NII] in the low resolution slitless grism spectra. We
construct emission line ratio maps and place the individual pixels in the
modified BPT. The extended LINER-like emission present in all of our
candidates, coupled with X-Ray properties consistent with star-forming galaxies
and weak [OIII]5007\AA\ detections, is inconsistent with purely
nuclear sources (LINERs) driven by active galactic nuclei. While recent
ground-based integral field unit spectroscopic surveys have revealed
significant evidence for diffuse LINER-like emission in galaxies within the
local universe , this work provides the first evidence for the
non-AGN origin of LINER-like emission out to high redshifts.Comment: 11 pages, 1 table, 6 figures, accepted for publication in the
Astrophysics Journal (ApJ
Dark energy constraints from cosmic shear power spectra: impact of intrinsic alignments on photometric redshift requirements
Cosmic shear constrains cosmology by exploiting the apparent alignments of
pairs of galaxies due to gravitational lensing by intervening mass clumps.
However galaxies may become (intrinsically) aligned with each other, and with
nearby mass clumps, during their formation. This effect needs to be
disentangled from the cosmic shear signal to place constraints on cosmology. We
use the linear intrinsic alignment model as a base and compare it to an
alternative model and data. If intrinsic alignments are ignored then the dark
energy equation of state is biased by ~50 per cent. We examine how the number
of tomographic redshift bins affects uncertainties on cosmological parameters
and find that when intrinsic alignments are included two or more times as many
bins are required to obtain 80 per cent of the available information. We
investigate how the degradation in the dark energy figure of merit depends on
the photometric redshift scatter. Previous studies have shown that lensing does
not place stringent requirements on the photometric redshift uncertainty, so
long as the uncertainty is well known. However, if intrinsic alignments are
included the requirements become a factor of three tighter. These results are
quite insensitive to the fraction of catastrophic outliers, assuming that this
fraction is well known. We show the effect of uncertainties in photometric
redshift bias and scatter. Finally we quantify how priors on the intrinsic
alignment model would improve dark energy constraints.Comment: 14 pages and 9 figures. Replaced with final version accepted in
"Gravitational Lensing" Focus Issue of the New Journal of Physics at
http://www.iop.org/EJ/abstract/1367-2630/9/12/E0
UBE2QL1 is Disrupted by a Constitutional Translocation Associated with Renal Tumor Predisposition and is a Novel Candidate Renal Tumor Suppressor Gene
Investigation of rare familial forms of renal cell carcinoma (RCC) has led to the identification of genes such as VHL and MET that are also implicated in the pathogenesis of sporadic RCC. In order to identify a novel candidate renal tumor suppressor gene, we characterized the breakpoints of a constitutional balanced translocation, t(5;19)(p15.3;q12), associated with familial RCC and found that a previously uncharacterized gene UBE2QL1 was disrupted by the chromosome 5 breakpoint. UBE2QL1 mRNA expression was downregulated in 78.6% of sporadic RCC and, although no intragenic mutations were detected, gene deletions and promoter region hypermethylation were detected in 17.3% and 20.3%, respectively, of sporadic RCC. Reexpression of UBE2QL1 in a deficient RCC cell line suppressed anchorage-independent growth. UBE2QL1 shows homology to the E2 class of ubiquitin conjugating enzymes and we found that (1) UBE2QL1 possesses an active-site cysteine (C88) that is monoubiquitinated in vivo, and (2) UBE2QL1 interacts with FBXW7 (an F box protein providing substrate recognition to the SCF E3 ubiquitin ligase) and facilitates the degradation of the known FBXW7 targets, CCNE1 and mTOR. These findings suggest UBE2QL1 as a novel candidate renal tumor suppressor gen
On the occupation of X-ray selected galaxy groups by radio AGN since z=1.3
Previous clustering analysis of low-power radio AGN has indicated that they
preferentially live in massive groups. The X-ray surveys of the COSMOS field
have achieved a sensitivity at which these groups are directly detected out to
z=1.3. Making use of Chandra-, XMM- and VLA-COSMOS surveys we identify radio
AGN members (10**23.6 < L_1.4GHz/(W/Hz) < 10**25) of galaxy groups (10**13.2 <
M_200/M_sun < 10**14.4; 0.1<z<1.3) and study i) the radio AGN -- X-ray group
occupation statistics as a function of group mass, and ii) the distribution of
radio AGN within the groups. We find that radio AGN are preferentially
associated with galaxies close to the center (< 0.2r_200). Compared to our
control sample of group members matched in stellar mass and color to the radio
AGN host galaxies, we find a significant enhancement of radio AGN activity
associated with 10**13.6 < M_200/M_sun < 10**14 halos. We present the first
direct measurement of the halo occupation distribution (HOD) for radio AGN,
based on the total mass function of galaxy groups hosting radio AGN. Our
results suggest a possible deviation from the usually assumed power law HOD
model. We also find an overall increase of the fraction of radio AGN in galaxy
groups (<1r_200), relative to that in all environments.Comment: 5 pages, 4 figures, accepted for publication in MNRAS Letter
Flood realities, perceptions, and the depth of divisions on climate
Research has led to broad agreement among scientists that anthropogenic climate change is happening now and likely to worsen. In contrast to scientific agreement, US public views remain deeply divided, largely along ideological lines. Science communication has been neutralised in some arenas by intense counter-messaging, but as adverse climate impacts become manifest they might intervene more persuasively in local perceptions. We look for evidence of this occurring with regard to realities and perceptions of flooding in the northeastern US state of New Hampshire. Although precipitation and flood damage have increased, with ample news coverage, most residents do not see a trend. Nor do perceptions about past and future local flooding correlate with regional impacts or vulnerability. Instead, such perceptions follow ideological patterns resembling those of global climate change. That information about the physical world can be substantially filtered by ideology is a common finding from sociological environment/society research
Ameliorating Systematic Uncertainties in the Angular Clustering of Galaxies: A Study using SDSS-III
We investigate the effects of potential sources of systematic error on the
angular and photometric redshift, z_phot, distributions of a sample of redshift
0.4 < z < 0.7 massive galaxies whose selection matches that of the Baryon
Oscillation Spectroscopic Survey (BOSS) constant mass sample. Utilizing over
112,778 BOSS spectra as a training sample, we produce a photometric redshift
catalog for the galaxies in the SDSS DR8 imaging area that, after masking,
covers nearly one quarter of the sky (9,913 square degrees). We investigate
fluctuations in the number density of objects in this sample as a function of
Galactic extinction, seeing, stellar density, sky background, airmass,
photometric offset, and North/South Galactic hemisphere. We find that the
presence of stars of comparable magnitudes to our galaxies (which are not
traditionally masked) effectively remove area. Failing to correct for such
stars can produce systematic errors on the measured angular auto-correlation
function, w, that are larger than its statistical uncertainty. We describe how
one can effectively mask for the presence of the stars, without removing any
galaxies from the sample, and minimize the systematic error. Additionally, we
apply two separate methods that can be used to correct the systematic errors
imparted by any parameter that can be turned into a map on the sky. We find
that failing to properly account for varying sky background introduces a
systematic error on w. We measure w, in four z_phot slices of width 0.05
between 0.45 < z_phot < 0.65 and find that the measurements, after correcting
for the systematic effects of stars and sky background, are generally
consistent with a generic LambdaCDM model, at scales up to 60 degrees. At
scales greater than 3 degrees and z_phot > 0.5, the magnitude of the
corrections we apply are greater than the statistical uncertainty in w.Comment: Accepted by MNRA
Clustering of Radio Galaxies and Quasars
We compute the cross-correlation between a sample of 14,000 radio-loud AGN
(RLAGN) with redshifts between 0.4 and 0.8 selected from the Sloan Digital Sky
Survey and a reference sample of 1.2 million luminous red galaxies in the same
redshift range. We quantify how the clustering of radio-loud AGN depends on
host galaxy mass and on radio luminosity. Radio-loud AGN are clustered more
strongly on all scales than control samples of radio-quiet galaxies with the
same stellar masses and redshifts, but the differences are largest on scales
less than 1 Mpc. In addition, the clustering amplitude of the RLAGN varies
significantly with radio luminosity on scales less than 1 Mpc. This proves that
the gaseous environment of a galaxy on the scale of its dark matter halo, plays
a key role in determining not only the probability that a galaxy is radio-loud
AGN, but also the total luminosity of the radio jet. Next, we compare the
clustering of radio galaxies with that of radio-loud quasars in the same
redshift range. Unified models predict that both types of active nuclei should
cluster in the same way. Our data show that most RLAGN are clustered more
strongly than radio-loud QSOs, even when the AGN and QSO samples are matched in
both black hole mass and radio luminosity. Only the most extreme RLAGN and
RLQSOs in our sample, with radio luminosities in excess of 10^26 W/Hz, have
similar clustering properties. The majority of the strongly evolving RLAGN
population at z~0.5 are found in different environments to the quasars, and
hence must be triggered by a different physical mechanism.Comment: 12 pages, 13 Figures, submitted to MNRA
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