238 research outputs found
Prevalência da infecção pelo vírus da hepatite C em comunidades remanescentes de quilombos no Brasil Central
In order to determine the prevalence of hepatitis C virus (HCV) infection in quilombo remnant communities in Central Brazil, 1,007 subjects were interviewed in all 12 communities existing in Mato Grosso do Sul State, Central Brazil. Blood samples were collected and sera were tested for anti-HCV by enzyme-linked immunosorbent assay. Positive samples were retested for confirmation using a line immunoassay and were also subjected to HCV RNA detection. The prevalence of HCV infection was 0.2%. This finding shows a low prevalence of HCV infection in quilombo remnant communities in Central Brazil.Com objetivo de estimar a prevalência da infecção pelo vírus da hepatite C (HCV) em comunidades remanescentes de quilombos no Brasil Central, 1.007 indivíduos foram entrevistados nas 12 comunidades quilombolas existentes no Estado de Mato Grosso do Sul, Brasil Central. Amostras sanguíneas foram coletadas e os soros testados para anti-HCV pelo ensaio imunoenzimático. As amostras positivas foram testadas pelo ensaio confirmatório "line immunoassay" e também submetidas à detecção do RNA-HCV. A prevalência da infecção pelo HCV foi de 0,2%. Este achado mostra uma baixa prevalência da infecção pelo HCV em comunidades remanescentes de quilombos no Brasil Central
Safety and feasibility of thullium laser transurethral resection of prostate for the treatment of benign prostatic enlargement in overweight patients
Objective: We aimed to determine safety and feasibility of thulium laser transurethral vapoenucleation of prostate (ThuVEP) for treatment of obese patients affected by benign prostatic hyperplasia (BPH). Methods: We retrospectively analysed data of 452 patients with BPH who underwent ThuVEP from February 2012 to March 2016 in a single center. Patients were divided into three groups according to body mass index (BMI, kg/m2): Normal weight (18.5 64 BMI < 25; Group A), overweight (25 64 BMI < 30; Group B) and obese (BMI 65 30; Group C), for a total of 412 patients evaluable for this study. Preoperative total serum prostate-specific antigen (PSA), digital rectal examination of the prostate, transrectal ultrasound (TRUS), renal ultrasound, urine culture, uroflowmetry, International Prostate Symptoms Score (IPSS), and Quality of Life (QoL) score were analyzed. Post-operative complications, hospital stay and days of catheterization, questionnaires and uroflowmetry at 1 and 3 months after surgery were evaluated. Preoperative data, surgical outcomes, complication rate and clinical outcomes were compared between groups. Results: The median age of patients was 69 years (Interquartile Range [IQR 10]). The preoperative median IPSS among groups was 19 (IQR 8.75), 20 (IQR 10), and 18 (IQR 10) respectively. At 1 and 3 months of follow-up, this value was 8 (IQR 7), 8 (IQR 4), 7 (IQR 5) and 5 (IQR 6.25), 5 (IQR 6), 6 (IQR 5), respectively (all p between groups > 0.05). There was no statistically significant difference among three groups as for hospital stay and days of catheterization (p > 0.05). Conclusion: Our results showed that ThuVEP was safe and feasible even in overweight patients with substantially enlarged prostate
Fast variability from black-hole binaries
Currently available information on fast variability of the X-ray emission
from accreting collapsed objects constitutes a complex phenomenology which is
difficult to interpret. We review the current observational standpoint for
black-hole binaries and survey models that have been proposed to interpret it.
Despite the complex structure of the accretion flow, key observational
diagnostics have been identified which can provide direct access to the
dynamics of matter motions in the close vicinity of black holes and thus to the
some of fundamental properties of curved spacetimes, where strong-field general
relativistic effects can be observed.Comment: 20 pages, 11 figures. Accepted for publication in Space Science
Reviews. Also to appear in hard cover in the Space Sciences Series of ISSI
"The Physics of Accretion onto Black Holes" (Springer Publisher
An overview of jets and outflows in stellar mass black holes
In this book chapter, we will briefly review the current empirical
understanding of the relation between accretion state and and outflows in
accreting stellar mass black holes. The focus will be on the empirical
connections between X-ray states and relativistic (`radio') jets, although we
are now also able to draw accretion disc winds into the picture in a systematic
way. We will furthermore consider the latest attempts to measure/order jet
power, and to compare it to other (potentially) measurable quantities, most
importantly black hole spin.Comment: Accepted for publication in Space Science Reviews. Also to appear in
the Space Sciences Series of ISSI - The Physics of Accretion on to Black
Holes (Springer Publisher
Allophoma brasiliensis J.L.V.R. Carvalho, J.D.P. Bezerra &amp; Souza-Motta (Didymellaceae, Pleosporales): first occurrence in an agricultural site from Brazilian Atlantic Forest
Allophoma brasiliensis J.L.V.R. Carvalho, J.D.P. Bezerra &amp; Souza-Motta is reported for the &#64257;rst time as endophyte from leaves of Capsicum annuum L. (Solanaceae) isolated in an agricultural site from Brazilian Atlantic Forest. For species determination, morphological characters were analysed along with a multigene analysis performed using the ITS region of the rDNA, the partial large subunit nuclear ribosomal RNA gene (LSU rRNA), the partial second largest subunit of the RNA polymerase II gene subunit (rpb2), and the partial &beta;&ndash;tubulin gene (tub2). A key to Allophoma Qian Chen &amp; L. Cai species is provided. This new record contributes to the global fungal diversity, indicating a new geographical distribution, and a new lifestyle
The balance of power: accretion and feedback in stellar mass black holes
In this review we discuss the population of stellar-mass black holes in our
galaxy and beyond, which are the extreme endpoints of massive star evolution.
In particular we focus on how we can attempt to balance the available accretion
energy with feedback to the environment via radiation, jets and winds,
considering also possible contributions to the energy balance from black hole
spin and advection. We review quantitatively the methods which are used to
estimate these quantities, regardless of the details of the astrophysics close
to the black hole. Once these methods have been outlined, we work through an
outburst of a black hole X-ray binary system, estimating the flow of mass and
energy through the different accretion rates and states. While we focus on
feedback from stellar mass black holes in X-ray binary systems, we also
consider the applicability of what we have learned to supermassive black holes
in active galactic nuclei. As an important control sample we also review the
coupling between accretion and feedback in neutron stars, and show that it is
very similar to that observed in black holes, which strongly constrains how
much of the astrophysics of feedback can be unique to black holes.Comment: To be published in Haardt et al. Astrophysical Black Holes. Lecture
Notes in Physics. Springer 201
Probing Jet Launching in Neutron Star X-Ray Binaries: The Variable and Polarized Jet of SAX J1808.4-3658
Indexación ScopusWe report on an optical photometric and polarimetric campaign on the accreting millisecond X-ray pulsar (AMXP) x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">SAX x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">4-x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">J1808.x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">4-x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">3658 during its 2019 outburst. The emergence of a low-frequency excess x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">in the spectral energy distribution x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">in the form of a red excess above the disk spectrum (seen most prominently x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">in the z, i, and R bands) is observed as the outburst evolves. This is indicative of optically thin synchrotron emission due to a jet, as seen previously x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">in this source and x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">in other AMXPs during outburst. At the end of the outburst decay, the source enters a reflaring state. The low-frequency excess is still observed during the reflares. Our optical (BVRI) polarimetric campaign shows variable linear polarization (LP) throughout the outburst. We show that this is intrinsic to the source, with low-level but significant detections (0.2%-2%) x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">in all bands. The LP spectrum is red during both the main outburst and the reflaring state, favoring a jet origin for this variable polarization over other interpretations, such as Thomson scattering with free electrons from the disk or the propelled matter. During the reflaring state, a few episodes with stronger LP levels (1%-2%) are observed. The low-level, variable LP is suggestive of strongly tangled magnetic fields near the base of the jet. These results clearly demonstrate how polarimetry is a powerful tool for x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">probing the magnetic field structure x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">in X-ray binary jets, as for active galactic nuclei jets. © 2020. The American Astronomical Society. All rights reserved..https://iopscience-iop-org.recursosbiblioteca.unab.cl/article/10.3847/1538-4357/abc68
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