Variable impedance LED matrix control system for lamps in PV applications

The interest in LED lighting has been growing recently due to the high efficacy, lifelime and ruggedness that this technology offers. However the key element to guarantee those parameters with these new electronic devices is to keep under control the working temperature of the semiconductor crystal. This paper propases a LED lamp design that fulfils the requ irements of a PV lighting systems, whose main quality criteria is reliability. It uses directly as a power supply a non·stabilized constant voltage source, as batteries. An electronic control architecture is used to regulate the current applied to the LEO matri)( according to their temperature and the voltage output value of the batteries with two pulse modulation signals (PWM) signals. The first one connects and disconnects the LEOs to the power supply and the second one connects and disconnects several emitters to the electric circuit changing its overall impedance. A prototype of the LEO lamp has been implemented and tested at different temperaturas and battery voltages

Radar Tracking System Using Contextual Information on a Neural Network Architecture in Air Combat Maneuvering

Air surveillance radar tracking systems present a variety of known problems related to uncertainty and lack of accurately in radar measurements used as source in these systems. In this work, we feature the theoretical aspects of a tracking algorithm based on neural network paradigm where, from discrete measurements provided by surveillance radar, the objective will be to estimate the target state for tracking purposes as accuracy as possible. The absence of an optimal statistical solution makes the featured neural network attractive despite the availability of complex and well-known filtering algorithms.Neural networks exhibit universal mapping capabilities that allow them to be used as a control tool for capturing hidden information about models learned from a dataset. We use these capabilities to let the network learn, not only from the received radar measurement information, but also from the aircraft maneuvering context, contextual information, where tracking application is working, taking into account this new contextual information which could be obtained from predefined, commonly used, and well-known aircraft trajectories. In this case study, the proposed solution is applied to a typical air combat maneuvering, a dogfight, a form of aerial combat between fighter aircraft. Advantages of integrating contextual information in a neural network tracking approach are demonstrated.This work was supported in part by ProjectsMEyC TEC2012- 37832-C02-01, MEyC TEC2011-28626-C02-02, and CAM CONTEXTS (S2009/TIC-1485).Publicad

INTERFAZ PARA LA SELECCIÓN DE MOTORES DE JAULA DE ARDILLA

En este artículo se desarrolla un algoritmo para la selección de motores de inducción trifásicos de jaula de ardilla, partiendo del conocimiento de la aplicación. El algoritmo es implementado en Microsoft Excel y parte de una metodología desarrollada que tiene en cuenta factores importantes, que en ocasiones se omiten y que intervienen en dicha selección. Todo con el fin de proporcionar una herramienta práctica que permite minimizar las fallas a causa de la mala selección y garantizar así, la continuidad del servicio

Association Between Substance Use Behaviors, Developmental Assets and Mental Health: A Glance at Latin American Young College Students

Positive Youth Development (PYD) is an approach that promotes resilience and focuses on youth strengths rather than their weaknesses as done by the traditional deficit-based perspective. Research in Europe and North America show that developmental assets are associated with school success, psychological well-being, and lower health risks among youth and young adults. However, not much research has been done on these associations in Latin American contexts. The purpose of this research study is to assess the association between substance use behaviors, such as drunkenness and the use of illicit drugs, and mental health, together with the mediating role of developmental assets representing youth strengths (e.g., social competence) and contextual resources (e.g., social support at home or school). Cross-national data was collected from Colombian (n = 210; 70.4% females) and Peruvian (n = 349; 66.5% females) 1st year university students. Results shed light on the protective role of developmental assets regarding substance use behaviors and mental well-being. Specifically, the results showed direct negative associations between developmental assets and substance use behaviors and positive associations of developmental assets with mental health indicators. Internal assets appear to be a stronger predictor of social, emotional, and psychological well-being compared to external assets. We did not find any statistical significance in the association of substance use behavior and mental health. We discuss implications regarding research, policy, and practice.publishedVersio

The geological guide of the Teide National Park: a case of educational geological guidebook

El Instituto Geológico y Minero de España, con la colaboración del Organismo Autónomo Parques Nacionales, ha iniciado la edición de una nueva serie de carácter didáctico-divulgativo: las Guías Geológicas de Parques Nacionales, con el fin de atender la demanda social de guías geológicas de los principales espacios naturales protegidos. La Guía Geológica del Parque Nacional del Teide es la primera de esta serie. El texto contiene una descripción de las principales formaciones volcánicas que conforman el parque y su entorno, así como de los eventos volcánicos más relevantes y de la historia geológica del Parque Nacional y de la isla de Tenerife, en el contexto de las islas Canarias. Una parte sustancial de la guía la compone la descripción de varios itinerarios geológicos. La guía incluye un mapa geológico y otro geomorfológico representados sobre un modelo de sombras elaborado a partir del Modelo Digital del Terreno (MDT).The Geological Survey of Spain (IGME) with de cooperation of the National Park Authorities has started the edition of a new tourist guidebook series: the National Park Geological Guidebooks. This new series intends to answer the growing social demand of geological guides in natural protected areas. The geological guide of the Teide National Park has been the first published volume of this series. A major part of the guide includes the description of main volcanic formations in the park and surrounding areas. A second part is devoted to the description of volcanic regional events and the geological history of the National Park area and the island of Tenerife, within the context of Canary Islands. A third, relevant part of the guide includes a description of some selected geological itineraries. The guide also includes a geological and a geomorphological map of the Park.Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

Consensus-based recommendations on physical activity and exercise in patients with diabetes at risk of foot ulcerations: a Delphi study

Background Patients with diabetes mellitus are exposed to important complications. Currently little evidence exist on the guidelines that these patients, at some risk of foot ulceration, should follow for physical exercise. Objectives To reach a consensus among multidisciplinary and international experts on physical activity/exercise recommendations for patients with diabetes, according to foot ulcer risk. Methods Using a three-round Delphi method, a panel composed of 28 multidisciplinary experts in the management of diabetic foot assessed 109 recommendations on physical activity/exercise for patients with diabetes mellitus, according to their risk of foot ulcer. Consensus was assumed when 80% of responses matched the same category (agreement/disagreement). Results Twenty-nine experts participated in the first and second rounds of consultation, and twenty-eight did so in the third, reaching final agreement on 86 of the 109 recommendations considered (78.9%). The study, thus, generated a consensus set of recommendations concerning different aspects of diabetic footcare before, during, and after exercise (e.g. when to examine the foot, how to assess it, what type of sock and insole to use, what types of exercise to perform, and when it is advisable to return to activity after an ulceration). Conclusion This Delphi study generated recommendations based on the consensus of international experts on physical activity and exercise by patient with diabetes at risk of ulceration. Recommendations considered the state of the foot and the patient's history and status before physical activity and included information on intensity, duration, frequency, and progressions of physical activity/exercise, and the use of custom-made plantar orthoses, shoe prescription, and the convenience of returning to physical activity after an ulceration

Planeación ambiental para la conservación de la biodiversidad en las áreas operativas de Ecopetrol: ventana Montes de María, Colosó, Sucre.

El estudio se realiza en la red hidrológica del municipio de Colosó y está determinada por la microcuenca del arroyo Colosó que tiene una extensión de 101,06 km con nacimiento en el arroyo Pitalcito a 600 msnm y desembocadura sobre el arroyo Pichilín (Alcaldía de Colosó 2008).BogotáPlaneación ambiental para la conservación de la biodiversidad en las áreas operativas de Ecopetro

Una España que envejece

257 p

Pobre incremento de la cobertura vacunal frente al VHA en personas que viven con el VIH, tras una intervención basada en la inmunización

[EN] Objectives: To assess HAV serologic and vaccination status among people who live with HIV (PLWH), and to evaluate the impact of a vaccination-based strategy on HAV-negative patients in Seville, Spain. Methods: Study with two time-overlapping phases: (i) cross-sectional study of HAV immunity prevalence among PLWH followed at a Spanish hospital between August 2019 and March 2020. (ii) Patients seronegative for HAV, reliably unvaccinated were included in a before-and-after quasi-experimental study, with an intervention focused on HAV vaccination according to national recommendations in force. Results: Six hundred and fifty-six patients were included, of which 111 [17%, 95% confidence interval (95% CI) 14–20%] were seronegative for HAV. Of these, 48 [43% (95% CI, 34–53%)] individuals were MSM. The absence of HAV immunity was attributed in 69 [62% (95% CI, 52–71%)] patients to non-referral to vaccination, followed by lack of achievement of a correct vaccination scheme [n = 26; 23% (95% CI, 16–32%)]. After the program implementation, 96 [15% (95% CI, 12–18%)] individuals were seronegative (17% vs. 15%, p = 0.256), of whom 42 [41% (95% CI, 32–51%)] were MSM. The absence of immunity after the intervention was mainly attributed to: adherence failure in 23 [24.0% (95% CI, 15.8–33.7%)] patients, on-course immunization scheme in 34 [33% (95% CI, 24–43%)] individuals and pending appointment at the vaccine delivery unit in 20 [20.8% (95% CI, 13.2–30.3%)] patients. Conclusions: A sizeable proportion of PLWH remains susceptible for HAV infection in future outbreaks. A program based on referral to the vaccine delivery unit yields poor results, largely due to program adherence failures. New strategies are needed to increase HAV vaccination coverage.[ES] Objetivos: Evaluar la prevalencia de inmunidad frente al VHA en personas que viven con VIH así como el impacto de una intervención basada en la vacunación de pacientes seronegativos frente al VHA. Métodos: Estudio con dos fases solapadas en el tiempo: 1) transversal de prevalencia de inmunidad frente al VHA en personas que viven con VIH seguidas en un hospital de tercer nivel, entre agosto de 2019 y el inicio de las medidas nacionales de contención de la epidemia por SARS-CoV-2, marzo de 2020. 2) Cuasiexperimental, con una intervención centrada en la vacunación frente a VHA de pacientes seronegativos, en la unidad responsable de esta. Resultados: Ciento once (17%, [95% IC, 14-20%]) de los 656 pacientes incluidos eran seronegativos frente al VHA. Las principales causas de la ausencia de inmunidad fueron: 69 (62% [95% IC, 52-71%]) individuos no derivados a la unidad responsable de la vacunación; 26 pacientes (23% [95% CI, 16-32%]) no completaron el esquema vacunal. Tras la intervención, 96 (15% [95% IC, 12-18%]) pacientes continuaron siendo seronegativos frente al VHA (comparada con la prevalencia basal, p = 0,256), 42 (18% [95% IC, 13-23%]) eran HSH. Las principales causas de la ausencia de inmunidad fueron: 26 (23% [95% IC, 15-32%]) individuos presentaron fallos de adherencia al circuito vacunal; 34 (33% [95% IC, 24-43%]) pacientes habían recibido una sola dosis; 22 (22% [95% IC, 14-31%]) seguían sin una primera valoración por parte de la unidad responsable de la vacunación. Conclusiones: Una proporción considerable de personas que viven con VIH, particularmente HSH, sigue siendo susceptible a la infección por VHA. La derivación sistemática a la unidad responsable de la vacunación se traduce en modestos incrementos de la prevalencia de inmunidad. Son necesarias nuevas estrategias para aumentar la cobertura vacunal.Peer reviewe

Incidence of recently acquired hepatitis C virus infection among HIV-infected patients in southern Spain.

Objectives: Spain is close to HCV microelimination, so rates of recently acquired HCV infection (RAHC) should decrease. Nowadays, men who have sex with men (MSM) carry the highest risk of HCV acquisition. Our aim was to estimate the incidence of and the factors associated with RAHC, together with reinfection rates, among patients sexually infected by HIV.Methods: Primary RAHC infection was diagnosed when anti-HCV antibody seroconversion was documented. In anti-HCV positive patients, initially without HCV viraemia, a diagnosis of reinfection was established if plasma HCV RNA was detected.Results: All 350 patients tested negative for anti-HCV at baseline and had at least one follow-up visit. Among them, there were 16 RAHC cases from 2016 to 2019. RAHC incidence rates [IR (95% confidence interval, CI)] per 100 person-years were 3.77 (0.5-12.9) in 2016, 1.85 (0.6-4.3) in 2017, 1.49 (0.4-3.8) in 2018 and 1.98 (0.6-4.5) in 2019. Only previous sexually transmitted infections [incidence rate ratio (IRR) = 18.23, 95% CI: 1.93-172.1; P = 0.011], male sex (IRR = 8.33, 95% CI: 1.38-54.15; P = 0.026) and sharing chem-sex drugs (IRR: 4.93, 95% CI: 1.17-20.76; P = 0.030), were independently associated with RAHC. Four out of 42 (9.5%) patients became reinfected. Conclusions: The incidence of RAHC among HIV-infected patients showed a decrease after 2016, although a lower but steady incidence of residual cases still remains. HCV reinfections showed a similar pattern. New infections were associated with sharing chem-sex drugs among MSM.This study was partly supported by grants from the Ministerio de Economía, Industria y competitividad, Instituto de Salud Carlos III (grant no. PI15/01124) and from Grupo de Estudio de Hepatitis Vírica-SEIMC (grant no. GEHEP-001). AG-S and AR-J are recipients of Miguel Servet Research Contracts by the Ministerio de Ciencia, Promoción y Universidades of Spain (CP18/00146; CP18/00111). JM is the recipient of a grant from the Servicio Andaluz de Salud de la Junta de Andalucía (grant no. B-0037). JAP is recipient of an intensification grant from the Instituto de Salud Carlos III (grant no. Programa-I3SNS)