147 research outputs found

    Monogamy and (anti)colonialities: an indigenous narrativa craftmanship

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    Neste trabalho buscou-se apresentar perspectivas indígenas às noções de monogamia e não monogamia, tendo o conceito de colonialidade como principal chave de análise. Como inspiração cosmogônica, foi utilizado o conceito de “artesania narrativa guarani”, através do qual foram avaliados os efeitos e reverberações da cristianização na construção da monogamia em Abya Ayla. O trançado teórico-temporal do artigo foi realizado em três fios: no primeiro, foram investigadas as relações entre monogamia e cristianização; no segundo, os efeitos contemporâneos dos discursos presentes nas cartas jesuíticas e no terceiro apresentaram-se as perspectivas filosóficas guarani sobre não monogamia. O referencial teórico foi construído de modo interdisciplinar, contando com as contribuições de historiografias, estudos descoloniais, anticoloniais e relatos orais. Salientou-se que a monogamia insere-se em uma conjuntura dos sistemas coloniais de monocultura (monoteísmo, monogamia, monossexismo) os quais têm em comum os princípios da exclusividade, não concomitância e não convivência. Por outro lado, a não monogamia indígena teria como princípio a floresta como signo de diversidade e concomitância. Como resultado, pontuou-se a importância das vozes indígenas na articulação de perspectivas não monogâmicas e de lutas anticoloniais, rumo a um reflorestamento emocional das relações não só inter humanos, mas com o planeta.info:eu-repo/semantics/publishedVersio

    LAGOVirtual: A Collaborative Environment for the Large Aperture GRB Observatory

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    We present the LAGOVirtual Project: an ongoing project to develop platform to collaborate in the Large Aperture GRB Observatory (LAGO). This continental-wide observatory is devised to detect high energy (around 100 GeV) component of Gamma Ray Bursts, by using the single particle technique in arrays of Water Cherenkov Detectors (WCD) at high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). This platform will allow LAGO collaboration to share data, and computer resources through its different sites. This environment has the possibility to generate synthetic data by simulating the showers through AIRES application and to store/preserve distributed data files collected by the WCD at the LAGO sites. The present article concerns the implementation of a prototype of LAGO-DR adapting DSpace, with a hierarchical structure (i.e. country, institution, followed by collections that contain the metadata and data files), for the captured/simulated data. This structure was generated by using the community, sub-community, collection, item model; available at the DSpace software. Each member institution-country of the project has the appropriate permissions on the system to publish information (descriptive metadata and associated data files). The platform can also associate multiple files to each item of data (data from the instruments, graphics, postprocessed-data, etc.).Comment: Second EELA-2 Conference Choroni, Venezuela, November 25th to 27th 200

    Sarilumab in patients admitted to hospital with severe or critical COVID-19: a randomised, double-blind, placebo-controlled, phase 3 trial

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    Background: Elevated proinflammatory cytokines are associated with greater COVID-19 severity. We aimed to assess safety and efficacy of sarilumab, an interleukin-6 receptor inhibitor, in patients with severe (requiring supplemental oxygen by nasal cannula or face mask) or critical (requiring greater supplemental oxygen, mechanical ventilation, or extracorporeal support) COVID-19. Methods: We did a 60-day, randomised, double-blind, placebo-controlled, multinational phase 3 trial at 45 hospitals in Argentina, Brazil, Canada, Chile, France, Germany, Israel, Italy, Japan, Russia, and Spain. We included adults (≥18 years) admitted to hospital with laboratory-confirmed SARS-CoV-2 infection and pneumonia, who required oxygen supplementation or intensive care. Patients were randomly assigned (2:2:1 with permuted blocks of five) to receive intravenous sarilumab 400 mg, sarilumab 200 mg, or placebo. Patients, care providers, outcome assessors, and investigators remained masked to assigned intervention throughout the course of the study. The primary endpoint was time to clinical improvement of two or more points (seven point scale ranging from 1 [death] to 7 [discharged from hospital]) in the modified intention-to-treat population. The key secondary endpoint was proportion of patients alive at day 29. Safety outcomes included adverse events and laboratory assessments. This study is registered with ClinicalTrials.gov, NCT04327388; EudraCT, 2020-001162-12; and WHO, U1111-1249-6021. Findings: Between March 28 and July 3, 2020, of 431 patients who were screened, 420 patients were randomly assigned and 416 received placebo (n=84 [20%]), sarilumab 200 mg (n=159 [38%]), or sarilumab 400 mg (n=173 [42%]). At day 29, no significant differences were seen in median time to an improvement of two or more points between placebo (12·0 days [95% CI 9·0 to 15·0]) and sarilumab 200 mg (10·0 days [9·0 to 12·0]; hazard ratio [HR] 1·03 [95% CI 0·75 to 1·40]; log-rank p=0·96) or sarilumab 400 mg (10·0 days [9·0 to 13·0]; HR 1·14 [95% CI 0·84 to 1·54]; log-rank p=0·34), or in proportions of patients alive (77 [92%] of 84 patients in the placebo group; 143 [90%] of 159 patients in the sarilumab 200 mg group; difference −1·7 [−9·3 to 5·8]; p=0·63 vs placebo; and 159 [92%] of 173 patients in the sarilumab 400 mg group; difference 0·2 [−6·9 to 7·4]; p=0·85 vs placebo). At day 29, there were numerical, non-significant survival differences between sarilumab 400 mg (88%) and placebo (79%; difference +8·9% [95% CI −7·7 to 25·5]; p=0·25) for patients who had critical disease. No unexpected safety signals were seen. The rates of treatment-emergent adverse events were 65% (55 of 84) in the placebo group, 65% (103 of 159) in the sarilumab 200 mg group, and 70% (121 of 173) in the sarilumab 400 mg group, and of those leading to death 11% (nine of 84) were in the placebo group, 11% (17 of 159) were in the sarilumab 200 mg group, and 10% (18 of 173) were in the sarilumab 400 mg group. Interpretation: This trial did not show efficacy of sarilumab in patients admitted to hospital with COVID-19 and receiving supplemental oxygen. Adequately powered trials of targeted immunomodulatory therapies assessing survival as a primary endpoint are suggested in patients with critical COVID-19. Funding: Sanofi and Regeneron Pharmaceuticals

    Status and performance of the underground muon detector of the Pierre Auger Observatory

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    The Auger Muons and Infill for the Ground Array (AMIGA) is an enhancement of the Pierre Auger Observatory, whose purpose is to lower the energy threshold of the observatory down to 1016.5 eV, and to measure the muonic content of air showers directly. These measurements will significantly contribute to the determination of primary particle masses in the range between the second knee and the ankle, to the study of hadronic interaction models with air showers, and, in turn, to the understanding of the muon puzzle. The underground muon detector of AMIGA is concomitant to two triangular grids of water-Cherenkov stations with spacings of 433 and 750 m; each grid position is equipped with a 30 m2 plastic scintillator buried at 2.3 m depth. After the engineering array completion in early 2018 and general improvements to the design, the production phase commenced. In this work, we report on the status of the underground muon detector, the progress of its deployment, and the performance achieved after two years of operation. The detector construction is foreseen to finish by mid-2022

    A combined fit of energy spectrum, shower depth distribution and arrival directions to constrain astrophysical models of UHECR sources

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    The combined fit of the measured energy spectrum and distribution of depths of shower maximum of ultra-high-energy cosmic rays is known to constrain the parameters of astrophysical scenarios with homogeneous source distributions. Further measurements show that the cosmic-ray arrival directions agree better with the directions and fluxes of catalogs of starburst galaxies and active galactic nuclei than with isotropy. Here, we present a novel combination of both analyses. For that, a three-dimensional universe model containing a nearby source population and a homogeneous background source distribution is built, and its parameters are adapted using a combined fit of the energy spectrum, depth of shower maximum distribution and energy-dependent arrival directions. The model takes into account a symmetric magnetic field blurring, source evolution and interactions during propagation. We use simulated data, which resemble measurements of the Pierre Auger Observatory, to evaluate the method’s sensitivity. With this, we are able to verify that the source parameters as well as the fraction of events from the nearby source population and the size of the magnetic field blurring are determined correctly, and that the data is described by the fitted model including the catalog sources with their respective fluxes and three-dimensional positions. We demonstrate that by combining all three measurements we reach the sensitivity necessary to discriminate between the catalogs of starburst galaxies and active galactic nuclei

    Performance of the 433 m surface array of the Pierre Auger Observatory

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    The Pierre Auger Observatory, located in western Argentina, is the world’s largest cosmic-ray observatory. While it was originally built to study the cosmic-ray flux above 1018.5 eV, several enhancements have reduced this energy threshold. One such enhancement is a surface array composed of a triangular grid of 19 water-Cherenkov detectors separated by 433 m (SD-433) to explore the energies down to about 1016 eV. We are developing two research lines employing the SD-433. Firstly, we will measure the energy spectrum in a region where previous experiments have shown evidence of the second knee. Secondly, we will search for ultra-high energy photons to study PeV cosmic-ray sources residing in the Galactic center. In this work, we introduce the SD-433 and we show that it is fully efficient above 5×1016 eV for hadronic primaries with θ < 45°. Using seven years of data, we present the parametrization of the lateral distribution function of measured signals. Finally, we show that an angular resolution of 1.8° (0.5°) can be attained at the lowest (highest) primary energies. Our study lays the goundmark for measurements in the energy range above 1016 eV by utilizing the SD-433 and thus expanding the scientific output of the Auger surface detector

    Deep-learning based reconstruction of the shower maximum Xmax using the water-Cherenkov detectors of the Pierre Auger Observatory

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    The atmospheric depth of the air shower maximum Xmax is an observable commonly used for the determination of the nuclear mass composition of ultra-high energy cosmic rays. Direct measurements of Xmax are performed using observations of the longitudinal shower development with fluorescence telescopes. At the same time, several methods have been proposed for an indirect estimation of Xmax from the characteristics of the shower particles registered with surface detector arrays. In this paper, we present a deep neural network (DNN) for the estimation of Xmax. The reconstruction relies on the signals induced by shower particles in the ground based water-Cherenkov detectors of the Pierre Auger Observatory. The network architecture features recurrent long short-term memory layers to process the temporal structure of signals and hexagonal convolutions to exploit the symmetry of the surface detector array. We evaluate the performance of the network using air showers simulated with three different hadronic interaction models. Thereafter, we account for long-term detector effects and calibrate the reconstructed Xmax using fluorescence measurements. Finally, we show that the event-by-event resolution in the reconstruction of the shower maximum improves with increasing shower energy and reaches less than 25 g/cm2 at energies above 2×1019 eV

    The XY Scanner – A Versatile Method of the Absolute End-to-End Calibration of Fluorescence Detectors

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    One of the crucial detector systems of the Pierre Auger Observatory is the fluorescence detector composed of 27 large-aperture wide-angle Schmidt telescopes. In the past, these telescopes were absolutely calibrated by illuminating the whole aperture with a uniform large-diameter light source. This absolute calibration was performed roughly once every three years, while a relative calibration was performed on a nightly basis. In this contribution, a new technique for an absolute end-to-end calibration of the fluorescence telescopes is presented. For this technique, a portable, calibrated light source mounted on a rail system is moved across the aperture of each telescope instead of illuminating the whole aperture at once. A dedicated setup using a combination of NIST traceable photodiodes to measure the mean intensity and a PMT for pulse-to-pulse stability tracking has been built for the absolute calibration of the light source. As a result of these complementary measurements, the pulse-to-pulse light source intensity can be known to the 3.5% uncertainty level. The analysis of the readout of the PMT camera at each position of the light source together with the knowledge of the light source emission provides an absolute end-to-end calibration of the telescope. We will give a brief overview of this novel calibration method and its current status as well as show preliminary results from the measurement campaigns performed so far

    Combined Search for UHE Neutrinos from Binary Black Hole Mergers with the Pierre Auger Observatory

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    We present searches for ultra-high energy (UHE) neutrinos (> 0.1 EeV) with the Pierre Auger Observatory, following up binary black hole (BBH) mergers detected by the LIGO and Virgo detectors via gravitational waves (GWs). In this work, the so-far published BBH mergers are combined as standard candles with a hypothetical isotropic UHE neutrino luminosity L(t − t0) as a function of the time after the respective merger, t − t0. The UHE neutrino emission spectrum is assumed to follow a power law distribution ∝ Ev−2. Using these assumptions, L(t − t0) is probed, taking into account the instantaneous effective area of the Pierre Auger Observatory to UHE neutrinos and the 3D sky localizations of the sources. No UHE neutrino candidates have been found and upper limits on L(t − t0) are obtained for the hypothetical cases of emissions lasting 24 hours and 60 days after the merger, respectively. The corresponding upper limit on the total energy per source emitted in UHE neutrinos does not depend on the emission duration and demonstrates the competitiveness of the Pierre Auger Observatory with dedicated neutrino telescopes

    Constraining Lorentz Invariance Violation using the muon content of extensive air showers measured at the Pierre Auger Observatory

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    Lorentz Invariance (LI) implies that the space-time structure is the same for all observers. On the other hand, various quantum gravity theories suggest that it may be violated when approaching the Planck scale. At extreme energies, like those available in the collision of Ultra-High Energy Cosmic Rays (UHECRs) with atmosphere nuclei, one should also expect a change in the interactions due to Lorentz Invariance Violation (LIV). In this work, the effects of LIV on the development of Extensive Air Showers (EAS) have been considered. After having introduced LIV as a perturbation term in the single-particle dispersion relation, a library of simulated showers with different energies, primary particles and LIV strengths has been produced. Possible LIV has been studied using the muon content of air showers measured at the Pierre Auger Observatory. Limits on LIV parameters have been derived from a comparison between the Monte Carlo expectations and muon fluctuation measurements from the Pierre Auger Observatory
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