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In this article the principle of the switched capacitor in a series RLC circuit is presented. The classical methods for phase angle control are described, and a novel control method, where the capacitor is placed in the centre of a bidirectional H bridge switches. Using an electronic circuit simulation program, the representative voltage and current curves are obtained. The phase angle at various transistor switching frequencies is determined. Also a study of the capacitor value and the switching frequency on the duty ratio resolution and phase angle is performed. The experimental results confirm the data acquired from computer analysis. [ABSTRACT FROM AUTHOR]

El ser humano, durante su desarrollo se ve enfrentado a experimentar diferentes cambios que van a repercutir en toda su existencia, originándole unos rasgos de personalidad perennes, compatibles con su propia identidad. Específicamente en la etapa de la adolescencia, ocurren transformaciones y ajustes determinados por factores biológicos, sicológicos y sociales. El comportamiento del adolescente es el producto y su consiguiente acúmulo, de las experiencias sociales vividas durante la infancia y la niñez y de la interpretación que elabore sobre las mismas; de esta forma, podemos observar que estos jóvenes, no sólo deben afrontar sus variaciones personajes sino que, además, requieren enfrentarse a las crisis sociales, económicas y culturales de la sociedad en que viven.

Andesiops peruvianus (Ulmer, 1920) is a small minnow mayfly with a distribution throughout the Andes Mountains, mainly in lotic environments. In recent years, the taxonomic status of the species has been shifting, even finding out molecular and morphological evidence to consider it as a cryptic species. In this work, we collected seven specimens of A. peruvianus from the Lake Titicaca in Peru, the type locality and perform molecular and morphological analyses to test their relationship with specimens from other regions. The species delimitation analysis revealed the existence of five MOTUs for specimens identified as A. peruvianus along the Andes Mountains, while the Lake Titicaca specimens formed a single MOTU with high interspecific distance. In this MOTU were found specimens with different types of abdominal gills, from translucent to markedly tracheated supporting the hypothesis of phenotypic plasticity at the abdominal gill level. Also, an extension in the range of tarsal claw denticles, from 10-12 to 10-14, were observed, higher than what were found in other regions. Our results support A. peruvianus as a species complex and reveal A. peruvianus from Titicaca as a single MOTU. Future morphological revisions of topotype specimens as well as from other Andean regions are required to strengthen the diagnosis of informative characteristics at both the larval and adult stage to elucidate the real status of the species.

Age-related eye diseases, including dry eye, glaucoma, age-related macular degeneration, and diabetic retinopathy, represent a major global health issue based on their increasing prevalence and disabling action. Unraveling the molecular mechanisms underlying these diseases will provide novel opportunities to reduce the burden of age-related eye diseases and improve eye health, contributing to sustainable development goals achievement. The impairment of neutrophil extracellular traps formation/degradation processes seems to be one of these mechanisms. These traps formed by a meshwork of DNA and neutrophil cytosolic granule proteins may exacerbate the inflammatory response promoting chronic inflammation, a pivotal cause of age-related diseases. In this review, we describe current findings that suggest the role of neutrophils and their traps in the pathogenesis of the above-mentioned age-related eye diseases. Furthermore, we discuss why these cells and their constituents could be biomarkers and therapeutic targets for dry eye, glaucoma, age-related macular degeneration, and diabetic retinopathy. We also examine the therapeutic potential of some neutrophil function modulators and provide several recommendations for future research in age-related eye diseases., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Introduction: Cerebral small vessel disease (SVD) predicts all-cause mortality in Eastern Asian and Caucasian populations. However, little is known about SVD impact in individuals of different races/ethnic groups. In this study, we sought to estimate the mortality risk according to the total SVD (tSVD) score in older adults of Amerindian ancestry., Methods: Participants aged ≥60 years from the prospective population-based Atahualpa Project cohort underwent brain MRI between June 2012 and June 2017. The tSVD score was calculated based on the presence of moderate-to-severe white matter hyperintensities, enlarged perivascular spaces, one or more lacune, and one or more cerebral microbleed. We ascertained all-cause mortality during post-MRI follow-up. Poisson regression and Cox-proportional hazards models adjusted for demographics and cardiovascular risk were obtained to estimate mortality risk according to the tSVD score., Results: Analysis included 375 participants with available brain MRI and clinical data (mean age 69.0 ± 8.3 years, 56.3% women). The tSVD score was 0 point in 216 individuals (57.6%), 1 point in 71 (18.9%), 2 points in 53 (14.1%), and 3-4 points in 35 (9.3%). Increasing tSVD score was associated with advancing age, hypertension, low level of education, and physical inactivity. Using tSVD score of 0 as reference, a multivariate Poisson regression model showed an increased mortality for individuals with a tSVD score 3-4 points (IRR: 2.27; 95% CI: 1.20-4.28). Likewise, in the Cox-proportional model adjusted for demographics and cardiovascular risk, participants with a tSVD score 3-4 maintained a greater than two-fold mortality risk when compared to those with tSVD score of 0 points (HR: 2.32; 95% CI: 1.23-4.39)., Conclusions: High-burden SVD as determined by the tSVD score predicts mortality in community-dwelling older adults of Amerindian ancestry. Incidental diagnosis of covert SVD should prompt aggressive control of cardiovascular health., Competing Interests: Declaration of conflicting interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© European Stroke Organisation 2021.)