Voltage compensation and power factor correction in distribution networks with DVR

The stability analysis and voltage regulation in distribution systems, as well as power quality problems such as voltage sags, swells, due to connection and disconnection of large loads, short circuits and the presence of non-linear loads, require of the consideration of adequate technical solutions. In this paper, a Dynamic Voltage Restorer ( DVR ) model based on a power converter scheme for voltage compensation due to the presence of sags of amplitude since 0.1pu to 0.9pu and swells with amplitude from 1.1pu to 1.9pu, and power factor correction in distribution networks is proposed. The results are verified through MATLAB & Simulink

Environmental and human factors drive the subtropical marine forests of Gongolaria abies-marina to extinction

Large brown macroalgae are foundational threatened species in coastal ecosystems from the subtropical northeastern Atlantic, where they have exhibited a drastic decline in recent years. This study describes the potential habitat of Gongolaria abies-marina, its current distribution and conservation status, and the major drivers of population decline. The results show a strong reduction of more than 97% of G. abies-marina populations in the last thirty years and highlight the effects of drivers vary in terms of spatial heterogeneity. A decrease in the frequency of high waves and high human footprint are the principal factors accounting for the long-term decline in G. abies-marina populations. UV radiation and sea surface temperature have an important correlation only in certain locations. Both the methodology and the large amount of data analyzed in this study provide a valuable tool for the conservation and restoration of threatened macroalgae.En prensa1,95

DSPWM multilevel technique of 27‐levels based on FPGA for the cascaded DC/AC power converter operation

In this paper, a digital sinusoidal pulse width modulation (DSPWM) multilevel technique of 27-levels based on field programmable gate array (FPGA) is introduced, as an alternative to control of the direct current/alternating current multilevel power converters. The implementation of this technique with an FPGA XC3S500E model is achieved in the Xilinx Spartan-3E FPGA platforms. An experimental prototype is implemented by 3-cascaded H-bridges controlled by the DSPWM multilevel technique, generating high efficiency, low cost, and lower harmonic content. The efficiency of the DSPWM multilevel technique using R, RL, RC, and RLC loads connected to the power network is verified

Classical dynamics of a two-species Bose-Einstein condensate in the presence of nonlinear maser processes

The stability analysis of a generalized Dicke model, in the semi-classical limit, describing the interaction of a two-species Bose-Einstein condensate driven by a quantized field in the presence of Kerr and spontaneous parametric processes is presented. The transitions from Rabi to Josephson dynamics are identified depending on the relative value of the involved parameters. Symmetry-breaking dynamics are shown for both types of coherent oscillations due to the quantized field and nonlinear optical processes.Comment: 12 pages, 5 figures. Accepted for publication as chapter in "Spontaneous Symmetry Breaking, Self-Trapping, and Josephson Oscillations in Nonlinear Systems

Determinants of image quality of rotational angiography for on-line assessment of frame geometry after transcatheter aortic valve implantation

To study the determinants of image quality of rotational angiography using dedicated research prototype software for motion compensation without rapid ventricular pacing after the implantation of four commercially available catheter-based valves. Prospective observational study including 179 consecutive patients who underwent transcatheter aortic valve implantation (TAVI) with either the Medtronic CoreValve (MCS), Edward-SAPIEN Valve (ESV), Boston Sadra Lotus (BSL) or Saint-Jude Portico Valve (SJP) in whom rotational angiography (R-angio) with motion compensation 3D image reconstruction was performed. Image quality was evaluated from grade 1 (excellent image quality) to grade 5 (strongly degraded). Distinction was made between good (grades 1, 2) and poor image quality (grades 3–5). Clinical (gender, body mass index, Agatston score, heart rate and rhythm, artifacts), procedural (valve type) and technical variables (isocentricity) were related with the image quality assessment. Image quality was good in 128 (72 %) and poor in 51 (28 %) patients. By univariable analysis only valve type (BSL) and the presence of an artefact negatively affected image quality. By multivariate analysis (in which BMI was forced into the model) BSL valve (Odds 3.5, 95 % CI [1.3–9.6], p = 0.02), presence of an artifact (Odds 2.5, 95 % CI [1.2–5.4], p = 0.02) and BMI (Odds 1.1, 95 % CI [1.0–1.2], p = 0.04) were independent predictors of poor image quality. Rotational angiography with motion compensation 3D image reconstruction using a dedicated research prototype software offers good image quality for the evaluation of frame geometry after TAVI in the majority of patients. Valve type, presence of artifacts and higher BMI negatively affect image quality

Más allá de las dimensiones del cuidado. Sistematización de la experiencia de enseñanza aprendizaje sobre el cuidado

The systematization of the teaching experience in human care is part of the project called Human Care in Nursing Education, Research, Care, and Administration. Its objective is to encourage the sharing of experiences in teaching and learning about Human Care, in order to make known the reach of the interaction and to recognize the knowledge that has been promoted or where a synergy has been generated from practice, collective and personal experience. The design of the study is qualitative; using the Participative Action Research and Learning by Experience methods. In this study, we describe what we do, feel and live, documenting the participants' opinion regarding, what is care? From the interpretation of opinion emerges a conceptual synergy unique, its own, and novel regarding the definition of care given by the respondents in a collective teaching session. Caring is to give love and support to a person in order to minimize the anguish and enter into a stage of tranquility, providing a feeling of security and confidence at the moment. (Affection 1): Caring is direct or indirect attention that is given to the human being founded on holism, observation, communication and feelings in order to strengthen the weaknesses and team work and, in this way, achieves what has been planned. (Affection 5) and among others, human care is the key to caring with human quality founded in affection, confidence and personal presence with the objective that the person achieves the greatest satisfaction in the moment and occasion of his/her health status. (Affection 24).Esta sistematización de experiencia sobre la enseñanza del Cuidado Humano se inscribe en el proyecto titulado Cuidado Humano en Educación, Investigación, Administración y Cuidado en Enfermería, cuya finalidad es favorecer el intercambio de experiencias en la enseñanza y el aprendizaje sobre el Cuidado Humano; concienciar los alcances de la interacción y reconocer el conocimiento que se ha potenciado o dónde se ha generado una sinergia desde la práctica, la experiencia colectiva y la experiencia personal. Materiales y Métodos: El diseño del estudio es cualitativo; utilizando el método Investigación Acción Participativa y el Aprendizaje por Experiencia. En el mismo se describe lo que hacemos, sentimos y vivimos, documentando la opinión de los participantes sobre ¿Qué es el cuidado? De la interpretación de las opiniones, emerge una sinergia conceptual, única, propia y novedosa sobre la definición de cuidado dada por los informantes, en una sesión colectiva de enseñanza. Los resultados son los conceptos de cuidado que emergen de forma empírica y significativa: entre otros, Cuidado es brindar amor y apoyo a la persona para que minimice la angustia y entre en un estadio de tranquilidad, proporcionándole en el momento, un sentimiento de seguridad y confianza. (Afecto 1); y entre otros, el cuidado humano es la clave de la atención, con calidad humana, fundamentada en el afecto, la confianza y con la presencia del personal, con el fin de que la persona alcance la mayor satisfacción, en el momento y en la ocasión, de su estado de salud. (Afecto 24). En conclusión, la sistematización de la práctica pedagógica sobre el cuidado humano proporciona una de las vías para hacer más significativo entre las enfermeras la contribución del cuidado en la vida de los cuidados y de los cuidadores como principio universal, conjuntamente, con el amor, en la vida de los humanos y de la humanidad

The relative age effect on physical fitness in preschool children

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ ¿ = 0.383; F10, 5996 = 369.64; p < 0.001, ¿p 2 = 0.381) and of quarter (Wilks’ ¿ = 0.874; F15, 8276.6 = 27.67; p < 0.001; ¿p 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers

RICORS2040 : The need for collaborative research in chronic kidney disease

Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true