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Tungsten oxide thin films have applications in various energy-related devices owing to their versatile semiconductor properties, which depend on the oxygen content and crystalline state. The concentration of electrons increases with intrinsic defects such as oxygen vacancies, which create new absorption bands that give rise to colored films. Disorders in the crystal structure produce additional changes in the electrical and optical characteristics. Here, WO3-x thin films are prepared on unheated glass substrates by reactive DC sputtering from a pure metal target, using the discharge power and the oxygen-to-argon pressure ratio as control parameters. A transition from amorphous to polycrystalline state is obtained by increasing the sputtering power and adjusting the oxygen content. The surface roughness is higher and the bandgap energy is lower for polycrystalline layers than for amorphous ones. Moreover, the electrical conductivity and sub-bandgap absorption increase as the oxygen content decreases.
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Al-doped ZnO combines high transparency and conductivity with abundant and non-toxic elements; making it suitable for optoelectronic devices with large-scale applications. In order to check the quality of the material deposited over large areas, spectroscopic ellipsometry is a powerful technique that allows the determination of various optical and electrical parameters by applying suitable oscillator models. This technique is used here to obtain sheet resistance and visible transmittance data at several equidistant points of Al:ZnO thin films deposited using DC sputtering on 15 cm × 15 cm glass substrates. Independent measurements using other optical (spectrophotometry) and electrical (four point probe) methods show analogous visible transmittance but somewhat higher resistance values than those obtained with ellipsometry, which is explained by the contribution of grain-boundary scattering compared to in-grain properties provided using ellipsometry. However, the mapping of the data gives a similar spatial distribution to the different types of measurement; therefore, proving the capacity of ellipsometry to study with a single tool the uniformity of the optical and electrical characteristics of large areas.
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In advanced breast cancer, biomarker identification and patient selection using a metastatic tumor biopsy is becoming more necessary. However, the biology of metastasis according to the organ site is largely unknown. Here, we evaluated the expression of 771 genes in 184 metastatic samples across 11 organs, including liver, lung, brain, and bone, and made the following observations. First, all PAM50 molecular intrinsic subtypes were represented across organs and within immunohistochemistry-based groups. Second, HER2-low disease was identified across all organ sites, including bone, and HER2 expression significantly correlated with ERBB2 expression. Third, the majority of expression variation was explained by intrinsic subtype and not organ of metastasis. Fourth, subtypes and individual subtype-related genes/signatures were significantly associated with overall survival. Fifth, we identified 74 genes whose expression was organ-specific and subtype-independent. Finally, immune profiles were found more expressed in lung compared to brain or liver metastasis. Our results suggest that relevant tumor biology can be captured in metastatic tissues across a variety of organ sites; however, unique biological features according to organ site were also identified and future studies should explore their implications in diagnostic and therapeutic interventions.
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Neoplasias da Mama , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Receptor ErbB-2/metabolismo , Transcriptoma/genéticaRESUMO
Introducción: La Pandemia COVID-19, ha tenido impactos negativos en la salud física y mental de las personas, así como las medidas adoptadas por los gobiernos, para prevenir el contagio masivo de la población como el confinamiento, el aislamiento social, el trabajo y educación virtual. Dentro de los afectados por estos cambios, se encontrarían los estudiantes universitarios del área de la salud, que además de estudiar en estas condiciones de pandemia, no han podido hacer sus prácticas de los servicios de salud. Esta situación de exposición al aislamiento, podría afectar la salud mental de los jóvenes estudiantes universitarios. Objetivo: determinar los niveles de depresión, ansiedad y estrés en estudiantes universitarios y su relación con variables sociodemográficas y las características del aislamiento social durante la Pandemia COVID-19. Métodos: Se realizó un estudio descriptivo, observacional, de corte transversal y cuantitativo, con una muestra de 818 estudiantes universitarios de facultades de ciencias de la salud, mediante el cuestionario autoadministrado DASS-21. Resultados: Los principales hallazgos fueron: una mayor prevalencia en niveles altos (severos y extremadamente severos) en la ansiedad, alcanzado casi a 4 de cada 10 de los evaluados; por otro lado, en depresión y el estrés, 2 de cada 10 de los evaluados, se encontraron en los niveles mencionados. En relación con las variables sociodemográficas, las relacionadas con el COVID-19 y aislamiento social, se hallaron diferencias estadísticamente significativas con el género (mujeres > varones), el haber tenido COVID-19 (Sí > No) y vivir con familiares como antes de la pandemia (Sí > No) obtuvieron en promedio mayores puntajes en depresión, ansiedad y estrés. Conclusión: Los estudiantes que presentaron mayor depresión, ansiedad y estrés con una diferencia significativa fueron de género femenino, con antecedentes de haber tenido Covid-19, menor contacto con familiares y haber cumplido con aislamiento social total.
Introduction: The COVID-19 Pandemic has had negative impacts on the physical and mental health of people, as well as the measures adopted by governments to prevent the massive contagion of the population, such as confinement, social isolation, virtual work, and virtual education. Among those affected by these changes would be university students in the health area who, in addition to studying in these pandemic conditions, have been unable to do their health service practices. This situation of exposure to isolation could affect the mental health of young university students. Objective: To determine the levels of depression, anxiety, and stress in university students, their relationship with sociodemographic variables, and the characteristics of social isolation during the COVID-19 Pandemic. Methods: A descriptive, observational, cross-sectional, and quantitative study was carried out with a sample of 818 university students from health sciences faculties using the DASS-21 self-administered questionnaire. Results: The main findings were a higher prevalence of high levels (severe and highly severe) in anxiety, reaching almost 4 out of 10 of those evaluated; On the other hand, in depression and stress, 2 out of 10 of those evaluated were found at the mentioned levels. Concerning the sociodemographic variables, those related to COVID-19 and social isolation, statistically significant differences were found with gender (women > men), having had COVID-19 (Yes > No), and living with relatives as before. On average, the pandemic (Yes > No) obtained higher scores in depression, anxiety, and stress. Conclusion: The students who presented greater depression, anxiety, and stress with a significant difference were female, with a history of having had Covid-19, less contact with family members, and having complied with total social isolation
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BACKGROUND: Preeclampsia origin has no conclusive explanation. As part of its etiology it has been proposed immunologic disorders. This work explores several lymphocytes subsets and postulates possible mechanisms involved in a lost of immune tolerance in this entity. OBJECTIVE: To compare cellular populations of CD3+ CD56+, CD4+ CD25+, T lymphocytes (CD4+ and CD8+) and NK cells subsets in preeclamptic and pregnant healthy women. PATIENTS AND METHODS: Through flow cytometry antibodies, peripheral blood mononuclear cells were obtained from both groups of patients. CD3+ CD56+, CD4+ CD25+, T lymphocytes (CD4+ and CD8+) and NK cells were identified. Mean and standard deviation, Student ttest and Pearson correlation were calculated to analyze differences between groups and correlation between mean blood pressure and different lymphocytes subsets; p < 0.05 was considered significant. RESULTS: CD3+ CD56+ cells percentage was lower in preeclamptic patients (2.7 vs 6.1%; p < 0.002), CD4+ CD25+ cells percentage tend to be lower too (22.11 vs 33.86; p = NS). Mean blood pressure shown negative correlation with CD3+ CD56+ cells percentage (rp - 0.666; p = 0.001) and with CD25 on CD4+ T lymphocytes surface (rp - 0.526; p < 0.025). CONCLUSIONS: Based on the association between mean blood pressure and lymphocytes percentage for these two cellular subsets, data obtained suggest that CD3+ CD56+ and CD4+ CD25+ cells play an important role in preeclampsia development.
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Subpopulações de Linfócitos , Pré-Eclâmpsia/imunologia , Adulto , Feminino , Humanos , Contagem de Linfócitos , GravidezRESUMO
CuIn(1-x)Ga(x)Se2 [CIGS; x=Ga/(In+Ga)] thin films are among of the best candidates as absorber materials for solar cell applications. The material quality and main properties of the polycrystalline absorber layer are critically influenced by deviations in the stoichiometry, particularly in the Cu/(In+Ga) atomic ratio. In this work a simple, sensitive and accurate method has been developed for the quantitative determination of these thin films by inductively coupled plasma optical emission spectrometry (ICP-OES). The proposed method involves an acid digestion of the samples to achieve the complete solubilization of CIGS, followed by the analytical determination by ICP-OES. A digestion procedure with 50% HNO3 alone or in the presence of 10% HCl was performed to dissolve those thin films deposited on glass or Mo-coated glass substrates, respectively. Two analytical lines were selected for each element (Cu 324.754 and 327.396 nm, Ga 294.364 and 417.206 nm, In 303.936 and 325.609 nm, Se 196.090 and 203.985 nm, and Mo 202.030 and 379.825 nm) and a study of spectral interferences was performed which showed them to be suitable, since they offered a high sensitivity and no significant inter-element interferences were detected. Detection limits for all elements at the selected lines were found to be appropriate for this kind of application, and the relative standard deviations were lower than 1.5% for all elements with the exception of Se (about 5%). The Cu/(In+Ga) atomic ratios obtained from the application of this method to CIGS thin films were consistent with the study of the structural and morphological properties by X-ray diffraction (XRD) and scanning electron microscopy (SEM).
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Es bien conocido el hecho de que en la diabetes mellitus totalmente desarrollada se produce una serie de alteraciones metabólicas que se traducen en complicaciones vasculares en el ojo y en el riñon y aumento en la frecuencia de enfermedad coronaria y vascular periférica entre otras. Aquí se describen algunos cambios que ocurren en distintos sitios corporales al inicio de la diabetes y que se asocian con alteraciones en la circulación, donde destacan los cambios en los eritrocitos, leucocitos y plaquetas, así como la viscosidad plasmática y sanguínea, además de cambios en las concentraciones de proteínas, lipoproteínas y lípidos