47 research outputs found

    Evaluación de las propiedades físico-mecánicas del ladrillo tipo V sustituyendo parcialmente la arcilla por ceniza de carbón vegetal, Chimbote – 2022

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    La ceniza de carbón vegetal es un residuo que podría ser altamente contaminante. Por tal motivo, se presenta el trabajo de investigación de tipo aplicada, con un enfoque cuantitativo y diseño cuasi experimental; con el objetivo principal de determinar las propiedades físico mecánicas del ladrillo tipo V al sustituir la arcilla por 5%, 10% y 15% de ceniza de carbón vegetal, para ello, se realizaron ensayos y estudios previos como los estudios de composición química, granulometría y el índice de plasticidad, tanto para las cenizas como para la arcilla. Luego, se elaboraron 100 ladrillos como muestra a las cuales se realizaron ensayos de resistencia a la compresión, variación dimensional, alabeo y absorción. Finalmente se concluye que: Las propiedades físico mecánicas del ladrillo tipo V al sustituir arcilla por ceniza de carbón vegetal, mejora cuando se sustituye en pequeñas proporciones como al 5%, y mientras que sea sustituido en mayor porcentaje, sus propiedades principales como la resistencia a la compresión, reducirá significativamente. Según la norma E070 a base de los resultados evaluados en el presente proyecto, se acepta a los ladrillos experimentales como unidad de albañilería. Demostrando, la viabilidad de utilizar la ceniza de carbón vegetal en un ladrillo de albañilería

    Influence of non-Consecutive Bar Breakages in Motor Current Signature Analysis for the Diagnosis of Rotor Faults in Induction Motors

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    (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Studies of rotor asymmetries in squirrel-cage induction motors have traditionally focused on analyses of the effects of the breakage of adjacent bars on the magnetic field and current spectrum. However, major motor manufacturers have reported cases where damaged bars are randomly distributed around the rotor perimeter of large HV machines. In some of these cases, the motors were being monitored under maintenance programs based on motor current signature analysis (MCSA), and the degree of degradation found in the rotor was much greater than that predicted by analysis of their current spectra. For this reason, a complete study was carried out, comprising a theoretical analysis, as well as simulation and tests, to investigate the influence that the number and location of faulty bars has on the traditional MCSA diagnosis procedure. From the theoretical analysis, based on the application of the fault-current approach and space-vector theory, a very simple method is deduced, which enables the left sideband amplitude to be calculated for any double bar breakage, per unit of the sideband amplitude corresponding to a single breakage. The proposed methodology is generalized for the estimation of the sideband amplitude in the case of multiple bar breakages and validated by simulation using a finite-element-based model, as well as by laboratory tests.This work was supported by the Spanish Ministerio de Educacion y Ciencia under ´ the framework of the Programa Nacional de proyectos de Investigacion Funda- ´mental Project Reference DPI2008-06583/DPI. Paper no. TEC-00393-2008Riera-Guasp, M.; Fernandez Cabanas, M.; Antonino-Daviu, J.; Pineda-Sanchez, M.; Rojas García, CH. (2010). Influence of non-Consecutive Bar Breakages in Motor Current Signature Analysis for the Diagnosis of Rotor Faults in Induction Motors. IEEE Transactions on Energy Conversion. 25(1):80-89. https://doi.org/10.1109/TEC.2009.2032622S808925

    Tuberculosis en pacientes tratados con antagonistas del factor de necrosis tumoral alfa en un área endémica, ¿vale la pena el riesgo?

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    Tumor necrosis factor alpha antagonists (TNFA) are biological agents to treat chronic inflammatory and autoimmune diseases. However, their use is associated with an increased rate of tuberculosis, endemic mycoses, and intracellular bacterial infections. Since tuberculosis is moderately to highly endemic in Colombia, the risk of these infections in patients treated with TNFAs may be higher than previously reported in Colombia. Recently, four patients have developed tuberculosis during TNFA therapy. Tuberculosis appeared between 3 to 24 months after initiation of TFNA therapy and was independent of previous tuberculin skin test status. A review of the relevant literature and recommLos antagonistas del factor de necrosis tumoral alfa (infliximab, adalimumab y etanercept) son agentes biológicos utilizados en el tratamiento de enfermedades inflamatorias crónicas y autoinmunes. Sin embargo, su uso está asociado con el incremento de la tasa de tuberculosis, micosis endémicas e infecciones bacterianas intracelulares. Dado que la tuberculosis es moderada/altamente endémica en Colombia, el riesgo de esta infección en los pacientes tratados con estos agentes biológicos puede incrementarse y hacer dicha tasa mayor que la informada previamente (tanto en Colombia como en el mundo). Se presentan cuatro pacientes que desarrollaron tuberculosis durante el tratamiento con antagonistas del factor de necrosis tumoral alfa. La presentación de la tuberculosis ocurrió en promedio 15 meses después del inicio del agente biológico y fue independiente de la prueba de tuberculina. Se hace una revisión del tema y se plantea la necesidad de implementar guías y estrategias gubernamentales orientadas a la detección y profilaxis de tuberculosis en este grupo de pacientes

    ADGRL3 (LPHN3) variants predict substance use disorder

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    Genetic factors are strongly implicated in the susceptibility to develop externalizing syndromes such as attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder, conduct disorder, and substance use disorder (SUD). Variants in the ADGRL3 (LPHN3) gene predispose to ADHD and predict ADHD severity, disruptive behaviors comorbidity, long-term outcome, and response to treatment. In this study, we investigated whether variants within ADGRL3 are associated with SUD, a disorder that is frequently co-morbid with ADHD. Using family-based, case-control, and longitudinal samples from disparate regions of the world (n = 2698), recruited either for clinical, genetic epidemiological or pharmacogenomic studies of ADHD, we assembled recursive-partitioning frameworks (classification tree analyses) with clinical, demographic, and ADGRL3 genetic information to predict SUD susceptibility. Our results indicate that SUD can be efficiently and robustly predicted in ADHD participants. The genetic models used remained highly efficient in predicting SUD in a large sample of individuals with severe SUD from a psychiatric institution that were not ascertained on the basis of ADHD diagnosis, thus identifying ADGRL3 as a risk gene for SUD. Recursive-partitioning analyses revealed that rs4860437 was the predominant predictive variant. This new methodological approach offers novel insights into higher order predictive interactions and offers a unique opportunity for translational application in the clinical assessment of patients at high risk for SUD

    Consenso colombiano para el manejo de pacientes con Hipofosfatasia

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    La hipofosfatasia (HPP) es una enfermedad metabólica, de tipo hereditario, causada por mutaciones en el gen ALPL. Teniendo en cuenta los retos del manejo adecuado de los pacientes con HPP, se realizó un consenso interdisciplinario de expertos (endocrocrinólogos pediatras, nefrólogos pediatras, ortopedistas infantiles y genetistas clínicos) con el fin de proponer recomendaciones de utilidad clínica para el diagnóstico, tratamiento y seguimiento de los pacientes colombianos con HPP. Estas sugerencias se realizan en el contexto de los diferentes tipos de presentaciones y las edades de los pacientes.Q41-7Hypophosphatasia (HPP) is a hereditary metabolic disease caused by mutations in the ALPL gene. Taking into account the challenges found in the adequate management of patients with HPP, an interdisciplinary consensus of experts (pediatric endocrinologists, pediatric nephrologists, pediatric orthopedists and clinical geneticists) was carried out, in order to propose recommendations of clinical utility for the diagnosis, treatment and follow-up of Colombian patients with HPP. These suggestions are made in the context of the different types of presentations and the ages of the patients

    Proyecto Ensamblando en Colombia

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    Los dos volúmenes de esta obra reúnen los resultados del proyecto ganador de la «Convocatoria nacional de proyectos bicentenario 1810-2010 “Historia social de la ciencia, la tecnología y la innovación en Colombia: ciudadanía, saberes y nación”», lanzada por Colciencias en el 2009. El proyecto, titulado «Ensamblado en Colombia: producción de saberes y construcción de ciudadanías» se propuso estudiar la manera como se constituyen en el presente y se han constituido en el pasado «asuntos de interés público» que tienen una clara dimensión epistémica y ontológica, pues la producción de saberes nos interpela y convoca como académicos y como ciudadanos, como académicas y como ciudadanas. Se trata de comprender cómo se ensamblan saberes, naturalezas, tecnologías y ciudadanías y de ensayar diálogos de estilos, enfoques y miradas que reconozcan la alteridad, la multiplicidad y la heteroglosia como partes esenciales en y para la producción simultánea de conocimiento y formas de sociedad

    Zoonosis, cambio climático y sociedad

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    La sociedad contemporánea se enfrenta a uno de los retos más grandes de la historia humana, el calentamiento global, mismo que acarrea enormes consecuencias, tales como los disturbios climáticos, así como los patrones de las enfermedades de origen animal transmisibles al hombre. Precisamente ante este escenario las instituciones educativas de nivel superior deben dar cumplimiento a su responsabilidad y ser las generadoras de alternativas de solución mediante el trabajo especializado de investigación; y para ello, la pesquisa científica es la mejor de las alternativas a nuestro alcance para comprender y encarar estos desafíos.Universidad Autónoma del Estado de México y Ediciones y Gráficos Eón, S.A. de C.V

    Common variants in Alzheimer’s disease and risk stratification by polygenic risk scores

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    Funder: Funder: Fundación bancaria ‘La Caixa’ Number: LCF/PR/PR16/51110003 Funder: Grifols SA Number: LCF/PR/PR16/51110003 Funder: European Union/EFPIA Innovative Medicines Initiative Joint Number: 115975 Funder: JPco-fuND FP-829-029 Number: 733051061Genetic discoveries of Alzheimer's disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer's disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer's disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer's disease

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

    A global experiment on motivating social distancing during the COVID-19 pandemic

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    Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
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