112 research outputs found
Cotrimoxazole Prophylaxis in HIV-Infected Pregnant Women and their Infants: Associations with Parasitemia, Common Illnesses and Birth Outcomes
Cotrimoxazole prophylactic treatment (CPT) is recommended by the World Health
Organization for prevention of opportunistic infections in adults and children. CPT is also
recommended for HIV-exposed infants while they remain at risk of HIV acquisition through
breastfeeding. The benefits of CPT have been well established in adults and HIV-infected
children but limited information exists among HIV-infected pregnant women and HIVexposed,
uninfected infants, including whether CPT offers protection against malaria. Using
data from a longitudinal study of prevention of mother-to-child transmission of HIV, we
examined the effect of CPT, initiated at six weeks of age, on adverse health outcomes during
the first 36 weeks of life in HIV-exposed uninfected infants, and the effect of CPT in HIVinfected
pregnant women on birth outcomes, incident malaria during pregnancy, and CD4
cell count at 24 weeks postpartum.
Among HIV-exposed, uninfected infants, CPT was associated with fewer cases of incident
malaria during the first 10 weeks of CPT exposure (hazard ratio (HR) 0.35, 95% confidence
interval (CI): 0.21, 0.57), but not during the remaining 20 weeks of CPT use (HR 0.93, 95%
CI: 0.67, 1.29). CPT did not offer protection against other serious illness, moderate or severe
anemia, or underweight. Among HIV-infected pregnant women, CPT was not associated
with a protective effect against malaria after adjustment for confounding (adjusted HR 0.66,
95% CI: 0.28, 1.52), when compared to women receiving intermittent preventive treatment
during pregnancy with sulfadoxine-pyrimethamine. CPT was not associated with a protective
effect in analyses of low birth weight or preterm birth. CPT was associated with a lower CD4
cell count at 24 weeks postpartum, among women receiving antiretrovirals (-77.6 cells/ÎŒL,
95% CI: -125.2, -30.1) and among women not receiving antiretrovirals (-33.7 cells/ ÎŒL, 95%
CI: -8.8, -58.6).
CPT appears to offer limited protection against malaria among HIV-exposed, uninfected
infants. Compared to intermittent preventive treatment administered during the first two
years of the study, CPT did not offer greater protection against malaria in HIV-infected
pregnant women, or against low birth weight or preterm birth. CPT was associated with a
lower CD4 cell count at 24 weeks compared to women not receiving CPT
First spectroscopic measurements of [OIII] emission from Lyman-alpha selected field galaxies at z ~ 3.1
We present the first spectroscopic measurements of the [OIII] 5007 A line in
two z ~ 3.1 Lyman-alpha emitting galaxies (LAEs) using the new near-infrared
instrument LUCIFER1 on the 8.4m Large Binocular Telescope (LBT). We also
describe the optical imaging and spectroscopic observations used to identify
these Lya emitting galaxies. Using the [OIII] line we have measured accurate
systemic redshifts for these two galaxies, and discovered a velocity offset
between the [OIII] and Ly-alpha lines in both, with the Lya line peaking 342
and 125 km/s redward of the systemic velocity. These velocity offsets imply
that there are powerful outflows in high-redshift LAEs. They also ease the
transmission of Lya photons through the interstellar medium and intergalactic
medium around the galaxies. By measuring these offsets directly, we can refine
both Lya-based tests for reionization, and Lya luminosity function measurements
where the Lya forest affects the blue wing of the line. Our work also provides
the first direct constraints on the strength of the [OIII] line in
high-redshift LAEs. We find [OIII] fluxes of 7 and 36 x 10^-17 erg s^-1 cm^-2
in two z ~ 3.1 LAEs. These lines are strong enough to dominate broad-band flux
measurements that include the line (in thiscase, K_s band photometry). Spectral
energy distribution fits that do not account for the lines would therefore
overestimate the 4000 A (and/or Balmer) break strength in such galaxies, and
hence also the ages and stellar masses of such high-z galaxies.Comment: Accepted by the Astrophysical Journal. 11 pages, 3 figures, 1 table
(emulateapj
Validity of US norms for the Bayley Scales of Infant Development-III in Malawian children
Most psychometric tests originate from Europe and North America and have not been validated in other populations. We assessed the validity of United States (US)-based norms for the Bayley Scales of Infant and Toddler Development-III (BSID-III), a neurodevelopmental tool developed for and commonly used in the US, in Malawian children
Zonation of Ribosomal DNA Transcription Defines a Stem Cell Hierarchy in Colorectal Cancer
Colorectal cancers (CRCs) are composed of an amalgam of cells with distinct genotypes and phenotypes. Here, we reveal a previously unappreciated heterogeneity in the biosynthetic capacities of CRC cells. We discover that the majority of ribosomal DNA transcription and protein synthesis in CRCs occurs in a limited subset of tumor cells that localize in defined niches. The rest of the tumor cells undergo an irreversible loss of their biosynthetic capacities as a consequence of differentiation. Cancer cells within the biosynthetic domains are characterized by elevated levels of the RNA polymerase I subunit A (POLR1A). Genetic ablation of POLR1A-high cell population imposes an irreversible growth arrest on CRCs. We show that elevated biosynthesis defines stemness in both LGR5+ and LGR5â tumor cells. Therefore, a common architecture in CRCs is a simple cell hierarchy based on the differential capacity to transcribe ribosomal DNA and synthesize proteins
Review of code and phase biases in multi-GNSS positioning
A review of the research conducted until present on the subject of Global Navigation Satellite System (GNSS) hardware-induced phase and code biases is here provided. Biases in GNSS positioning occur because of imperfections and/or physical limitations in the GNSS hardware. The biases are a result of small delays between events that ideally should be simultaneous in the transmission of the signal from a satellite or in the reception of the signal in a GNSS receiver. Consequently, these biases will also be present in the GNSS code and phase measurements and may there affect the accuracy of positions and other quantities derived from the observations. For instance, biases affect the ability to resolve the integer ambiguities in Precise Point Positioning (PPP), and in relative carrier phase positioning when measurements from multiple GNSSs are used. In addition, code biases affect ionospheric modeling when the Total Electron Content is estimated from GNSS measurements. The paper illustrates how satellite phase biases inhibit the resolution of the phase ambiguity to an integer in PPP, while receiver phase biases affect multi-GNSS positioning. It is also discussed how biases in the receiver channels affect relative GLONASS positioning with baselines of mixed receiver types. In addition, the importance of code biases between signals modulated onto different carriers as is required for modeling the ionosphere from GNSS measurements is discussed. The origin of biases is discussed along with their effect on GNSS positioning, and descriptions of how biases can be estimated or in other ways handled in the positioning process are provided.QC 20170922</p
Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial
Background
Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy
The Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V
The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the
first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises
three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black
Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains
extensive targeting information for the two multi-object spectroscopy programs
(MWM and BHM), including input catalogs and selection functions for their
numerous scientific objectives. We describe the production of the targeting
databases and their calibration- and scientifically-focused components. DR18
also includes ~25,000 new SDSS spectra and supplemental information for X-ray
sources identified by eROSITA in its eFEDS field. We present updates to some of
the SDSS software pipelines and preview changes anticipated for DR19. We also
describe three value-added catalogs (VACs) based on SDSS-IV data that have been
published since DR17, and one VAC based on the SDSS-V data in the eFEDS field.Comment: Accepted to ApJ
The eighteenth data release of the Sloan Digital Sky Surveys : targeting and first spectra from SDSS-V
The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains extensive targeting information for the two multi-object spectroscopy programs (MWM and BHM), including input catalogs and selection functions for their numerous scientific objectives. We describe the production of the targeting databases and their calibration- and scientifically-focused components. DR18 also includes ~25,000 new SDSS spectra and supplemental information for X-ray sources identified by eROSITA in its eFEDS field. We present updates to some of the SDSS software pipelines and preview changes anticipated for DR19. We also describe three value-added catalogs (VACs) based on SDSS-IV data that have been published since DR17, and one VAC based on the SDSS-V data in the eFEDS field.Publisher PDFPeer reviewe
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