2,703 research outputs found

    Prediction of corona and multipactor RF breakdown thresholds using the CEST (Corona Simulation Electron Tool) software

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    This is an electronic version of the paper presented at the International workshop in Multipactor, Corona and Passive Intermodulation (MULCOPIM), held in Valencia (Spain) on 2008.This work was supported by ESA-ESTEC under program A=4025 ITT ESA entitled Surface treatment and coating for the reduction of multipactor and passive intermodulation (PIM) effects in RF components

    Diaphragmatic Rupture Due To Closed Thoracobdominal Trauma: A Case Report

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    Background. Diaphragmatic injuries (DI) represent less than 1% of traumatic injuries; they are a marker of severe trauma due to associated injuries, although they often go undiagnosed as they remain hidden. If undetected, delayed herniation and strangulation of the abdominal organs into the chest cavity will result as the defect in the diaphragm is not repaired. DI occurs from penetrating or blunt trauma. The former occurs in approximately 67% of cases; direct injury to the diaphragm caused by automobile accidents has been reported. The remaining third is due to falls and crush injuries. Blunt trauma causes larger tears, even bilateral. Mortality from DI reaches 25% of cases and is higher in patients with blunt mechanisms of injury in the acute setting due to associated injuries. Mortality due to delayed presentation with hernia of abdominal contents into the chest due to previous penetrating trauma is 20% and increases with intestinal strangulation. Case presentation. Male, two years, and eight months-old, admitted to the emergency department due to thoraco-abdominal trauma due to being crushed by a truck tire. Tachypnea and stable vital signs were observed. Chest X-ray revealed elevated diaphragm and right pleural effusion. The patient continued to have dyspnea. Abdominal ultrasound confirmed elevation of the hemidiaphragm. Computed tomography of the chest showed the hepatic gland within the chest cavity. In the operating room, a right lateral thoracotomy was performed, observing diaphragmatic rupture. To correct and restore the hepatic gland to its normal anatomical site, the ruptured diaphragm was sutured with 2-0 Prolene®, supported with a bovine pericardium band, and subsequently a 12-Fr® chest tube was placed. In the end, it was closed by planes. Conclusions. The patient presented a blunt diaphragmatic injury. Intra-abdominal pressure increased above the tensile strength of diaphragmatic tissue. The patient evolved favorably in the postoperative period. He was kept under observation for ten days and was discharged without complications. After discharge, follow-up was performed without observing a diaphragmatic hernia or other injury

    Evidence of ongoing radial migration in NGC 6754: Azimuthal variations of the gas properties

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    Understanding the nature of spiral structure in disk galaxies is one of the main, and still unsolved questions in galactic astronomy. However, theoretical works are proposing new testable predictions whose detection is becoming feasible with recent development in instrumentation. In particular, streaming motions along spiral arms are expected to induce azimuthal variations in the chemical composition of a galaxy at a given galactic radius. In this letter we analyse the gas content in NGC 6754 with VLT/MUSE data to characterise its 2D chemical composition and Hα\alpha line-of-sight velocity distribution. We find that the trailing (leading) edge of the NGC 6754 spiral arms show signatures of tangentially-slower, radially-outward (tangentially-faster, radially-inward) streaming motions of metal-rich (poor) gas over a large range of radii. These results show direct evidence of gas radial migration for the first time. We compare our results with the gas behaviour in a NN-body disk simulation showing spiral morphological features rotating with a similar speed as the gas at every radius, in good agreement with the observed trend. This indicates that the spiral arm features in NGC 6754 may be transient and rotate similarly as the gas does at a large range of radii.Comment: 8 pages, 4 figures, accepted for publication in ApJL 2016 September 2

    Seudomicetoma dermatofítico en un gato persa : aspectos clínicos, patológicos y evolutivos

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    En este trabajo presentamos los aspectos clínicos, anatomopatológicos y evolutivos de un caso de dermatitis piogranulomatosa múltiple causada por hongos del género Microsporum, también conocida como seudomicetoma dermatofítico, en un gato persa, no castrado, de un año de edad al comienzo de la enfermedad. Las lesiones se caracterizaron macroscópicamente por la formación de numerosos nódulos de diferentes tamaños, localizados en la cabeza y antebrazo derecho, extendiéndose posteriormente a zona dorso lateral del tronco. La evolución de estos nódulos, que se generalizaron en algo menos de un mes, era hacia la coalescencia y fistulización, con descarga de un material grumoso blanco-grisáceo. El estudio histopatológico reveló una dermatitis piogranulomatosa, supeficial y profunda, caracterizada por presentar en el centro de los granulomas agregados de hongos septados inmersos en una matriz acidófila. La extirpación quirúrgica de un gran número de nódulos proporcionó mejorías transitorias, aunque reaparecieron nuevas lesiones. En este trabajo se describe la evolución tras dos años de seguimiento clínico. Tras el tratamiento con griseofulvina no se detectan nuevas lesiones después de 6 meses de su aplicación y seguimiento.This paper reports the clinical and histopathological features of a case of pyogranulomatous dermatitis caused by Microsporum fungi, a condition also known as dermatophyte pseudomycetoma, in a eneyear-old Persian cat. Grossly apparent fistulized nodules of varying sizes displaying a granular discharge were localized on the head, back, elbow and tail. Microscopic analysis revealed a deep piogranulomatous dermatitis characterized by centrally-located clusters of fungi within an acidophilic matrix. In just under a month, nodules had beco me generalized. Partial surgical excision and non-specific treatment provided temporary improvement, but new lesions subsequentlyappeared

    Herschel Far-IR counterparts of SDSS galaxies: Analysis of commonly used Star Formation Rate estimates

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    We study a hundred of galaxies from the spectroscopic Sloan Digital Sky Survey with individual detections in the Far-Infrared Herschel PACS bands (100 or 160 μ\mum) and in the GALEX Far-UltraViolet band up to z\sim0.4 in the COSMOS and Lockman Hole fields. The galaxies are divided into 4 spectral and 4 morphological types. For the star forming and unclassifiable galaxies we calculate dust extinctions from the UV slope, the Hα\alpha/Hβ\beta ratio and the LIR/LUVL_{\rm IR}/L_{\rm UV} ratio. There is a tight correlation between the dust extinction and both LIRL_{\rm IR} and metallicity. We calculate SFRtotal_{total} and compare it with other SFR estimates (Hα\alpha, UV, SDSS) finding a very good agreement between them with smaller dispersions than typical SFR uncertainties. We study the effect of mass and metallicity, finding that it is only significant at high masses for SFRHα_{H\alpha}. For the AGN and composite galaxies we find a tight correlation between SFR and LIR_{IR} (σ\sigma\sim0.29), while the dispersion in the SFR - LUV_{UV} relation is larger (σ\sigma\sim0.57). The galaxies follow the prescriptions of the Fundamental Plane in the M-Z-SFR space.Comment: 24 pages, 23 figures, accepted for publication in MNRA

    Clinical Characteristics and Risk Factors For Mortality During the \u27First Wave\u27 of COVID-19 In Reynosa, Tamaulipas

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    Background: The COVID-19 pandemic has impacted public health in Mexico. As of February 2020, there have been at least four waves of contagion that resulted in 5.82 million positive cases and more than 325 thousand deaths. At the beginning of the COVID-19 pandemic, hospital and population-based information was available, frequently with non-specific symptoms. Little was known about the risk factors for mortality in specific conditions. We described the clinical characteristics of patients with COVID-19 in Reynosa, Tamaulipas during 2020 and identified the risk factors for mortality. Methods: The COVID-19 cases registered from March to November 2020 in Reynosa were divided into survivors and non-survivors. The study had a retrospective cohort design. Data was obtained from the platform of the Respiratory Disease Surveillance System (SISVER), belonging to the National Epidemiological Surveillance System (SINAVE) of the Mexican Ministry of Health (https://sinave.gob.mx/). The variables considered were the age and gender of each patient. Twenty-five symptoms were included (fever, cough, headache, myalgia, arthralgia, among others); the outcome variable was the detection of COVID-19. Associated comorbidities were diabetes, obesity, hypertension, among others. The outcome variable was mortality. Data were analyzed using χ2 tests, Mann-Whitney tests, principal component analysis, and the Cox regression model. Results:The highest number of COVID-19 cases and deaths was observed in July, in men between 36-40 years old. The most frequent symptoms (37-51%) were headache, fever, cough, myalgia, and arthralgia. Clinical characteristics between survivors and non-survivors were significant (P Conclusions: The most frequent symptoms in positive COVID-19 patients in Reynosa during 2020 were headache, fever, cough, myalgia, and arthralgia. Age, gender and diabetes, hypertension, heart disease, COPD, and CKD increase mortality. The factors with the highest risk of death were age over 80 years, admitted to the ICU or intubated

    Erosional and depositional contourite features at the transition between the western Scotia Sea and southern South Atlantic Ocean: links with regional water-mass circulation since the Middle Miocene

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    The aim of the present study was to characterise the morpho-sedimentary features and main stratigraphic stacking pattern off the Tierra del Fuego continental margin, the north-western sector of the Scotia Sea abyssal plain (Yaghan Basin) and the Malvinas/Falkland depression, based on single- and multi-channel seismic profiles. Distinct contourite features were identified within the sedimentary record from the Middle Miocene onwards. Each major drift developed in a water depth range coincident with a particular water mass, contourite terraces on top of some of these drifts being associated with interfaces between water masses. Two major palaeoceanographic changes were identified. One took place in the Middle Miocene with the onset of Antarctic Intermediate Water flow and the enhancement of Circumpolar Deep Water (CDW) flow, coevally with the onset of Weddell Sea Deep Water flow in the Scotia Sea. Another palaeoceanographic change occurred on the abyssal plain of the Yaghan Basin in the Late Miocene as a consequence of the onset of Southeast Pacific Deep Water flow and its complex interaction with the lower branch of the CDW. Interestingly, these two periods of change in bottom currents are coincident with regional tectonic episodes, as well as climate and Antarctic ice sheet oscillations. The results convincingly demonstrate that the identification of contourite features on the present-day seafloor and within the sedimentary record is the key for decoding the circulation of water masses in the past. Nevertheless, further detailed studies, especially the recovery of drill cores, are necessary to establish a more robust chronology of the evolutionary stages at the transition between the western Scotia Sea and the southern South Atlantic Ocean.Fil: Pérez, Lara F.. Instituto Andaluz de Ciencias de la Tierra; España. Geological Survey of Denmark and Greenland; DinamarcaFil: Hernández Molina, F. Javier. Royal Holloway University of London; Reino UnidoFil: Esteban, Federico Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Tassone, Alejandro Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Piola, Alberto Ricardo. Ministerio de Defensa. Armada Argentina. Servicio de Hidrografía Naval; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Maldonado, Andrés. Instituto Andaluz de Ciencias de la Tierra; EspañaFil: Preu, Benedict. Chevron North Sea; Reino UnidoFil: Violante, Roberto Antonio. Ministerio de Defensa. Armada Argentina. Servicio de Hidrografía Naval; ArgentinaFil: Lodolo, Emanuele. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; Itali

    Environmentally friendly analysis of emerging contaminants by pressurized hot water extraction-stir bar sorptive extraction-derivatization and gas chromatography-mass spectrometry

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    This work describes the development, optimiza- tion, and validation of a new method for the simultaneous determination of a wide range of pharmaceuticals (beta- blockers, lipid regulators ... ) and personal care products (fragrances, UV filters, phthalates ... ) in both aqueous and solid environmental matrices. Target compounds were extracted from sediments using pressurized hot water ex- traction followed by stir bar sorptive extraction. The first stage was performed at 1,500 psi during three static extrac- tion cycles of 5 min each after optimizing the extraction temperature (50 – 150 °C) and addition of organic modifiers (% methanol) to water, the extraction solvent. Next, aqueous extracts and water samples were processed using polydime- thylsiloxane bars. Several parameters were optimized for this technique, including extraction and desorption time, ionic strength, presence of organic modifiers, and pH. Fi- nally, analytes were extracted from the bars by ultrasonic irradiation using a reduced amount of solvent (0.2 mL) prior to derivatization and gas chromatography – mass spectrome- try analysis. The optimized protocol uses minimal amounts of organic solvents (<10 mL/sample) and time ( ≈ 8 h/sam- ple) compared to previous ex isting methodologies. Low standard deviation (usually below 10 %) and limits of de- tection (sub-ppb) vouch for the applicability of the method- ology for the analysis of target compounds at trace levels. Once developed, the method was applied to determin
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