ABSTRACT:Here we report the results of several U-Pb zircon ages, made to generate an integrated history for the Rio Negro-Juruena tectonic province, for the northwestern part of the Amazonian Craton. This region comprises granitoid rocks, described as calc-alkaline syntectonic gneisses, granites and migmatites, affected by medium level amphibolite facies metamorphism. The new measurements, with the available Rb-Sr and K-Ar ages, indicate the formation of these rocks within a series of essentially juvenile magmatic arcs, that are closely related with subduction. Sm-Nd analyses indicate that all samples, regardless of their zircon ages, yielded T DM model ages roughly between 1.9 and 2.2 Ga, suggesting the absence of a much older source material. In the northeastern part (areas of Puerto Inírida and San Carlos), the Atabapo belt comprises rocks formed within a period of about 60 Ma, from 1800 to 1740 Ma. In the southwestern region, including the towns of Mitú and Iauaretê, the granitoids formed in the Vaupés belt between 1580 and 1520 Ma. Finally, the available K-Ar measurements indicate the onset of the Nickerie-K'Mudku intraplate heating event, with temperature above 300 o C within the entire region at 1200 -1300 Ma.KEYWORDS: Amazonian Craton; Rio Negro-Juruena province; geochronology; zircon ages; tectonic history.
RESUMO: Este trabalho inclui diversas idades U-Pb SHRIMP e LA_ICP-MS em zircão, produzidas para contribuir com o conhecimento da história geológica da província tectônica Rio Negro-Juruena na parte noroeste do Craton Amazônico. A região é constituída por rochas granitoides, descritas como gnaisses, granitos e migmatitos cálcio-alcalinos
The new coronavirus disease (COVID-19) is a challenge for clinical decision-making and the effective allocation of healthcare resources. An accurate prognostic assessment is necessary to improve survival of patients, especially in developing countries. This study proposes to predict the risk of developing critical conditions in COVID-19 patients by training multipurpose algorithms. We followed a total of 1040 patients with a positive RT-PCR diagnosis for COVID-19 from a large hospital from São Paulo, Brazil, from March to June 2020, of which 288 (28%) presented a severe prognosis, i.e. Intensive Care Unit (ICU) admission, use of mechanical ventilation or death. We used routinely-collected laboratory, clinical and demographic data to train five machine learning algorithms (artificial neural networks, extra trees, random forests, catboost, and extreme gradient boosting). We used a random sample of 70% of patients to train the algorithms and 30% were left for performance assessment, simulating new unseen data. In order to assess if the algorithms could capture general severe prognostic patterns, each model was trained by combining two out of three outcomes to predict the other. All algorithms presented very high predictive performance (average AUROC of 0.92, sensitivity of 0.92, and specificity of 0.82). The three most important variables for the multipurpose algorithms were ratio of lymphocyte per C-reactive protein, C-reactive protein and Braden Scale. The results highlight the possibility that machine learning algorithms are able to predict unspecific negative COVID-19 outcomes from routinely-collected data.
BackgroundThe Hamilton Depression Rating Scale (HAM-D) and the Montgomery–Asberg Depression Scale (MADRS) are used worldwide and considered standard scales for evaluating depressive symptoms. This paper aims to investigate the psychometric proprieties (reliability and validity) of these scales in a Brazilian sample, and to compare responses in bipolar and unipolar patients.MethodsThe sample comprised 91 patients with either bipolar I or major depressive disorder from a psychiatric institute at São Paulo, Brazil. Participants were recruited and treated by clinicians through the Structured Interview for DSM-IV criteria, and had previously been interviewed by a trained, blind tester.ResultsBoth scales indicated good reliability properties; however, the MADRS reliability statistics were higher than those of the HAM-D for detecting initial symptoms of unipolar depression. Correlation between the tests was moderate. Despite demonstrating adequate validity, neither test achieved the levels of sensitivity and specificity required for identification of a cutoff score to differentiate bipolar I and unipolar patients.ConclusionsBoth scales demonstrate adequate reliability and validity for assessing depressive symptoms in the Brazilian sample, and are good options to complement psychiatric diagnosis, but are not appropriate for distinguishing between the two affective disorder types.
BackgroundTreatment of bipolar disorder (BD) usually requires drug combinations. Combinations of lithium plus valproic acid (Li/VPA) and lithium plus carbamazepine (Li/CBZ) are used in clinical practice but were not previously compared in a head-to-head trial.ObjectiveThe objective of this trial was to compare the efficacy and tolerability of Li/VPA versus Li/CBZ in treating type 1 BD in any phase of illness in young individuals.MethodsLICAVAL was a randomized, unicenter, open-label, parallel-group trial that was conducted from January 2009 to December 2012 in a tertiary hospital in São Paulo, Brazil. Participants were between 18 and 35 years old and were followed up for 2 years. Our primary outcome was the number of participants achieving/maintaining response and remission during the acute and maintenance phases of BD treatment, respectively. Other outcomes assessed were symptom severity and adverse events throughout the study. In the analysis of the primary outcome, we compared groups by using a two-way repeated measures analysis of variance and estimated effect sizes by using Cohen’s d.ResultsOf our 64 participants, 36 were allocated to Li/VPA and 28 to Li/CBZ. Our sample was composed predominantly of females (66.6%) and the average age was 27.8 years. A total of 27 (45.0%) participants had depression, 17 (28.3%) had mania/hypomania, and 16 (26.7%) had a mixed state. We found no between-group differences in CGI-BP (Clinical Global Impression Scale modified for use in bipolar disorder) scores (P = 0.326) or in any other outcome. Side effects differed significantly between groups only in the first week of treatment (P = 0.021), and there were more side effects in the Li/VPA group. Also, the Li/VPA group gained weight (+2.1 kg) whereas the Li/CBZ group presented slight weight loss (−0.2 kg).ConclusionOur study suggests that Li/VPA and Li/CBZ have similar efficacy and tolerability in BD but that Li/CBZ might have metabolic advantages in the long term.Trial registrationClinicalTrials.gov identifier: NCT00976794. Registered on September 9, 2009.
Culture supernatants offour Campylobacterjejuni strains induced a net sodium secretory flux (plasma-lumen) and an impaired glucose transport in perfused jejunal segments of adult rats in vivo.
Abstract-In this paper, we evaluate the error criticality of radiation-induced errors on modern High-Performance Computing (HPC) accelerators (Intel Xeon Phi and NVIDIA K40) through a dedicated set of metrics. We show that, as long as imprecise computing is concerned, the simple mismatch detection is not sufficient to evaluate and compare the radiation sensitivity of HPC devices and algorithms. Our analysis quantifies and qualifies radiation effects on applications' output correlating the number of corrupted elements with their spatial locality. Also, we provide the mean relative error (dataset-wise) to evaluate radiation-induced error magnitude.We apply the selected metrics to experimental results obtained in various radiation test campaigns for a total of more than 400 hours of beam time per device. The amount of data we gathered allows us to evaluate the error criticality of a representative set of algorithms from HPC suites. Additionally, based on the characteristics of the tested algorithms, we draw generic reliability conclusions for broader classes of codes. We show that arithmetic operations are less critical for the K40, while Xeon Phi is more reliable when executing particles interactions solved through Finite Difference Methods. Finally, iterative stencil operations seem the most reliable on both architectures.
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