18 research outputs found

    Distortion of the QRS in elderly patients with myocardial infarction

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    Background: Distortion of the terminal portion of the QRS in the initial electrocardiogram (ECG) is a strong predictor of adverse outcome in myocardial infarction. Our purpose is to assess the relationship of distortion of QRS and other ECG characteristics with older age. Methods and results: We analysed 634 consecutive patients (age 62.6 &#177; 13.7, 77% male) admitted in the first 12 hours of ST-elevation myocardial infarction. Two groups of age were defined: < 75 years-old and &#8805; 75 years-old. Additionally, we defined two ECG groups according to the presence of ST segment elevation with distortion of the terminal portion of the QRS in two or more adjacent leads (QRS+) or the absence of this pattern (QRS&#8211;). Older people had more often QRS+ (30% vs. 20%, p = 0.023). The older group with QRS+ had an in-hospital mortality of 18%, vs. 7% with QRS&#8211; (p = 0.04), and an incidence of major adverse events of 40% vs. 14% (p = 0.002). In the multivariate analysis, age &#8805; 75 years was an independent predictor of distortion of the QRS (odds ratio 2.1, 1.2&#8211;4.9, p = 0.016). Conclusions: The distortion of the terminal portion of the QRS in myocardial infarction is more frequent in elderly people, and is significantly related to adverse prognosis. This ECG finding can be helpful to promptly stratify the risk in elderly patient

    Determinación de hidrocarburos del petróleo en matrices acuosas mediante el empleo de la espectroscopía infrarroja

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    Los hidrocarburos totales de petróleo constituyen los agentes contaminantes del agua de mayor relevancia; pueden estar presentes en los sistemas de almacenamiento y las fuentes de abastecimiento subterráneas y superficiales debido a fugas, derrames, vertimientos y al deficiente manejo de residuos que contengan estos compuestos orgánicos. El objetivo de este trabajo es desarrollar un procedimiento analítico para cuantificar hidrocarburos en matrices acuosas mediante el empleo de la espectroscopía infrarroja de rango medio y tetracloroetileno como solvente de extracción. Se empleó la técnica de transmisión en celdas de cuarzo de 30 mm de espesor y se realizó la medición de la altura máxima de la señal en 2930 cm-1 correspondiente a la vibración de estiramiento C-H asimétrico de metilenos. El error medio de calibración y el límite de cuantificación fueron igual a 0,0002 mg/ml. Se obtuvieron recobrados de 77 y 84 % para los niveles de concentración 0,2640 y 0,5280 mg/l, respectivamente. El error global en las concentraciones fue 0,0001 mg/l y las desviaciones estándares relativas fueron inferiores al 5 %. El procedimiento propuesto es adecuado para el fin previsto en el intervalo de concentraciones de. 0,0002 a 0,0819 mg/ml

    Degradation mechanism analysis in temperature stress tests on III-V ultra-high concentrator solar cells using a 3D distributed model

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    A temperature stress test was carried out on GaAs single-junction solar cells to analyze the degradation suffered when working at ultra-high concentrations. The acceleration of the degradation was realized at two different temperatures: 130 °C and 150 °C. In both cases, the degradation trend was the same, and only gradual failures were observed. A fit of the dark I–V curve at 25 °C with a 3D distributed model before and after the test was done. The fit with the 3D distributed model revealed degradation at the perimeter because the recombination current in the depletion region of the perimeter increased by about fourfold after the temperature stress test. Therefore, this test did not cause any morphological change in the devices, and although the devices were isolated with silicone, the perimeter region was revealed as the most fragile component of the solar cell. Consequently, the current flowing beneath the busbar favors the progression of defects in the device in the perimeter region

    Search for subsolar-mass black hole binaries in the second part of Advanced LIGO’s and Advanced Virgo’s third observing run

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    We describe a search for gravitational waves from compact binaries with at least one component with mass 0.2 M⊙–1.0 M⊙ and mass ratio q ≥ 0.1 in Advanced LIGO and Advanced Virgo data collected between 1 November 2019, 15:00 UTC and 27 March 2020, 17:00 UTC. No signals were detected. The most significant candidate has a false alarm rate of 0.2yr−1 ⁠. We estimate the sensitivity of our search over the entirety of Advanced LIGO’s and Advanced Virgo’s third observing run, and present the most stringent limits to date on the merger rate of binary black holes with at least one subsolar-mass component. We use the upper limits to constrain two fiducial scenarios that could produce subsolar-mass black holes: primordial black holes (PBH) and a model of dissipative dark matter. The PBH model uses recent prescriptions for the merger rate of PBH binaries that include a rate suppression factor to effectively account for PBH early binary disruptions. If the PBHs are monochromatically distributed, we can exclude a dark matter fraction in PBHs fPBH ≳ 0.6 (at 90% confidence) in the probed subsolar-mass range. However, if we allow for broad PBH mass distributions we are unable to rule out fPBH = 1. For the dissipative model, where the dark matter has chemistry that allows a small fraction to cool and collapse into black holes, we find an upper bound fDBH &lt; 10−5 on the fraction of atomic dark matter collapsed into black holes

    Undertreatment of pain and low use of opioids in Latin America

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    Pain is highly prevalent among the adult Latin American population. However, many patients with moderate to severe pain do not have access to effective pain management with opioids due to limited access to healthcare, overuse of nonopioid analgesics, regulatory barriers and lack of appropriate information about opioids. There is scarce training on use of opioids among physicians and other healthcare providers, which leads to misconceptions, mainly related to a fear of prescribing opioids. Although opioids are safe and effective drugs for the treatment of moderate to severe chronic pain, the use of opioids in Latin American nations is clearly below standards compared with developed countries

    Estudio seroepidemiológico y entomológico sobre la enfermedad de Chagas en un área infestada por Triatoma maculata (Erichson 1848) en el centro-occidente de Venezuela An entomological and seroepidemiological study of Chagas' disease in an area in central-western Venezuela infested with Triatoma maculata (Erichson 1848)

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    En el presente trabajo se realizó un estudio seroepidemiológico, entomológico y de factores de riesgo para la infestación de las viviendas en un área infestada por Triatoma maculata (Parroquia Xaguas, Municipio Urdaneta, Estado Lara, Venezuela). Se muestrearon 140 viviendas, 509 personas y 110 cánidos, a los cuales se les determinó anticuerpos séricos anti-Trypanosoma cruzi mediante ELISA y MABA, utilizando antígenos recombinantes. La infección por Tr. cruzi de los triatominos fue determinada por microscopía óptica y PCR. Los resultados mostraron una seroprevalencia en humanos de 1,57% y en cánidos de 6,36%. De los 545 triatominos capturados 97,98% fueron T. maculata, 1,65% Eratyrus mucronatus y 0,37% Panstrongylus geniculatus; con índices vectoriales de infección 0,36%, infestación 16,4%, colonización 39,1%, coinfestación 8,6% y dispersión 100%. La presencia de vectores en el domicilio y peridomicilio estuvo asociada a la presencia de gallinas, desorden en el peridomicilio, caprinos, gallineros y/o distribución del domicilio. Los resultados permiten concluir que T. maculata es el vector predominante en la región, con capacidad de infestar y colonizar el domicilio y estaría involucrado en la transmisión de la enfermedad de Chagas.<br>This article presents a study on seroepidemiological, entomologic, and risk factors for domiciliary infestation in a circumscribed area infested with Triatoma maculata in Parroquia Xaguas, Urdaneta Municipality, Lara State, Venezuela. One hundred and forty households, 509 persons, and 110 dogs were sampled. Serum anti-Trypanosoma cruzi antibodies were determined by means of ELISA and MABA techniques using recombinant antigens. Tr. cruzi infection in the triatomines was determined by direct microscopy and PCR. According to the results, 1.57% of humans and 6.36% of dogs were positive for serum anti-Tr. cruzi antibodies. Triatomine species were: 97.98% T. maculata, 1.65% Eratyrus mucronatus, and 0.37% Panstrongylus geniculatus. Vector indices were: 0.36% vector infection, 16.4% household infestation, 39.1% household colonization, 8.6% household co-infestation, and 100% vector dispersion. Domiciliary and peridomiciliary infestation was associated with the presence of chickens and disorderly goat corrals, chicken coops, and domiciliary distribution. The results strongly suggest that T. maculata is the predominant Tr. cruzi vector in the area and that due to its capacity to infest and colonize human dwellings, it could be involved in Chagas' disease transmission

    Gaia Data Release 3: Reflectance spectra of Solar System small bodies

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    30 pages, 26 figuresThe Gaia mission of the European Space Agency (ESA) has been routinely observing Solar System objects (SSOs) since the beginning of its operations in August 2014. The Gaia data release three (DR3) includes, for the first time, the mean reflectance spectra of a selected sample of 60 518 SSOs, primarily asteroids, observed between August 5, 2014, and May 28, 2017. Each reflectance spectrum was derived from measurements obtained by means of the Blue and Red photometers (BP/RP), which were binned in 16 discrete wavelength bands. We describe the processing of the Gaia spectral data of SSOs, explaining both the criteria used to select the subset of asteroid spectra published in Gaia DR3, and the different steps of our internal validation procedures. In order to further assess the quality of Gaia SSO reflectance spectra, we carried out external validation against SSO reflectance spectra obtained from ground-based and space-borne telescopes and available in the literature. For each selected SSO, an epoch reflectance was computed by dividing the calibrated spectrum observed by the BP/RP at each transit on the focal plane by the mean spectrum of a solar analogue. The latter was obtained by averaging the Gaia spectral measurements of a selected sample of stars known to have very similar spectra to that of the Sun. Finally, a mean of the epoch reflectance spectra was calculated in 16 spectral bands for each SSO. The agreement between Gaia mean reflectance spectra and those available in the literature is good for bright SSOs, regardless of their taxonomic spectral class. We identify an increase in the spectral slope of S-type SSOs with increasing phase angle. Moreover, we show that the spectral slope increases and the depth of the 1 um absorption band decreases for increasing ages of S-type asteroid families
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