Ubicación óptima de generación distribuida y dispositivos de protección usando optimización matemática

En este trabajo de presenta una metodología para resolver el problema de ubicación óptima de dispositivos de protección y generación distribuida en sistemas de distribución de energía eléctrica. Para solucionar éste problema se formula un modelo de programación no lineal entero mixto, el cual tiene como propósito minimizar el indicador de contabilidad SAIFI (System Average Interruption Frequency Index) sujeto a un conjunto de restricciones técnicas. El modelo matemático desarrollado en este trabajo está basado en la formulación presentada en [5] y para darle solución al problema se empleó el solver de programación no lineal BONMIN disponible en el software de optimización comercial GAMS. Para comprobar el desempeño de la metodología se consideran dos sistemas de pruebas de diferentes tamaños disponibles en la literatura especializada

Efectos clínicos del pedaleo pasivo en personas con lesión medular torácica crónica

Introducción: el pedaleo pasivo (PP) es considerado una herramienta en la rehabilitación de personas con lesiónmedular (LM). Objetivo: revisar la evidencia científica sobre los efectos clínicos producidos por intervenciones que emplean PP en personas con lesión medular torácica crónica. Metodología: revisión narrativa. Se realizó unabúsqueda en las bases de información  científica MEDLINE, CINAHL, LILACS, PEDro y Clinicalkey de artículos en inglés y español, con términos como “spinal cord injury”, “thoracic injuries”, “passive pedaling”, “cycling passive” y “protocol”, entre otros. Resultados: se obtuvieron 14 artículos que describen efectos limitados a nivel de los sistemas cardiovascular, neuromuscular y musculoesquelético; se encontró heterogeneidad clínica en los sujetos del estudio, así como diferencias en los parámetros de realización del pedaleo. Conclusiones: los estudios del PP en personas con LM torácica crónica evalúan en su mayoría el efecto de una única sesión. Los cambioscardiovasculares son estudiados con mayor frecuencia, aunque se requieren más investigaciones.Introduction: Passive leg cycling is considered as a tool in rehabilitation of people with spinal cord injury (SCI). Objective: To review the scientific evidence on the clinical effects produced by interventions that use passive leg cycling in people with chronic thoracic spinal cord injury. Methodology: Narrative review. A search was performed by using the MEDLINE, CINAHL, LILACS, PEDro and Clinicalkey databases, for articles in English and Spanish, with terms such as “spinal cord injury”, “thoracic injuries”, “passive pedaling”, “passive cycling” and “protocol”, among others. Results: 14 papers were included in our research which described limited effects at the level of the cardiovascular, neuromuscular and musculoskeletal systems. We found clinical heterogeneity in the subjects, as well as differences in the cycling parameters used by authors. Conclusions: Studies of PP in people with chronic thoracic SCI mostly evaluated the effect of a single session. Cardiovascular changes were mostly studied; however, more evidence is needed.Introducción: el pedaleo pasivo (PP) es considerado una herramienta en la rehabilitación de personas con lesiónmedular (LM). Objetivo: revisar la evidencia científica sobre los efectos clínicos producidos por intervenciones que emplean PP en personas con lesión medular torácica crónica. Metodología: revisión narrativa. Se realizó unabúsqueda en las bases de información  científica MEDLINE, CINAHL, LILACS, PEDro y Clinicalkey de artículos en inglés y español, con términos como “spinal cord injury”, “thoracic injuries”, “passive pedaling”, “cycling passive” y “protocol”, entre otros. Resultados: se obtuvieron 14 artículos que describen efectos limitados a nivel de los sistemas cardiovascular, neuromuscular y musculoesquelético; se encontró heterogeneidad clínica en los sujetos del estudio, así como diferencias en los parámetros de realización del pedaleo. Conclusiones: los estudios del PP en personas con LM torácica crónica evalúan en su mayoría el efecto de una única sesión. Los cambioscardiovasculares son estudiados con mayor frecuencia, aunque se requieren más investigaciones

Competitive Risaralda, generating research alliance for development

El presente libro lleva como título “Risaralda competitiva, generando alianzas en investigación para el desarrollo”, resultado del V encuentro de investigadores del departamento de Risaralda realizado en el mes de noviembre del año 2020. Evento en el cual se presentaron las últimas investigaciones realizadas en las diferentes instituciones educativas del departamento; quienes hacen parte de la Mesa de Investigaciones de Risaralda; ejercicio de gran interés que arroja resultados de investigaciones en diferentes áreas como son las Ciencias Agrícolas, Ciencias sociales, Ciencias de la salud, Ciencias de la tecnología y la información

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Factores de riesgo psicosociales y ambientales asociados a trastornos mentales

In Colombia, there are few studies on the association of psychosocial and environmental factors with the most prevalent mental disorders; such studies are important due to the context of violence, social insecurity, and job and economic instability in the country. The objective of this study was to identify the psychosocial and environmental risk factors for mental disorders, in users of psychological services in Colombia. The Mini International Neuropsychiatric Interview and a Questionnaire to evaluate the Axis-IV of the DSM-IV-TR were applied to 490 participants. The analysis comprised descriptive statistics and risk factors. As risk factors for depression, there were identified housing problems, access to health care services, problems related to the primary group, economics, problems of the social environment, and labor. For generalized anxiety, there were identified economic and education issues. For panic disorders, the risk factors were related to social environment, and for social phobia, the risk factors were problems in education, work and social environment.En Colombia, son escasos los estudios sobre la asociación de los factores psicosociales y medioambientales con trastornos mentales de mayor prevalencia; tales estudios son necesarios debido al contexto de violencia, inseguridad social e inestabilidad laboral y económica del país. El objetivo de este estudio fue identificar los factores de riesgo psicosociales y ambientales de los trastornos mentales, en los usuarios de servicios de psicología de Colombia. Para ello, se aplicaron el Mini International Neuropsychiatric Interview y un cuestionario de evaluación del Eje IV del DSM-IV-TR, a 490 participantes. Se utilizaron análisis descriptivos y de factores de riesgo. Como factor de riesgo para la depresión, se identificaron los problemas de vivienda, acceso a los servicios de asistencia sanitaria, los relativos al grupo primario, los económicos, del ambiente social y los problemas laborales. Para la ansiedad generalizada se identificaron los problemas económicos y los relativos a la enseñanza. Para los trastornos de pánico, fueron relevantes los problemas relacionados con el ambiente social, y para la fobia social, los problemas de enseñanza, los laborales y el ambiente social