438 research outputs found

    Migración tecnológica utilizando VDSL/FTTX para mejorar los servicios de telecomunicaciones de una red de acceso en Guano/Technological migration using VDSL/FTTX to improve telecommunications services in an access network in Guano

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    Este trabajo detalla el uso eficiente y reutilización de recursos de infraestructura a través de la migración de una red de acceso convencional a una nueva red que implemente tecnología VDSL/FTTX para mejorar los servicios de telecomunicaciones en la ciudad Guano por intermedio de CNT EP. Se realizó un análisis comprensivo del estado actual de redes FTTX que utilizan tecnología VDSL para establecer el aporte en la mejora de servicios en redes implementadas. Por otro lado, se realizaron mediciones de los principales parámetros eléctricos (resistencia de bucle, atenuación y señal ruido) en 427 redes telefónicas en diferentes sectores del cantón Guano para conocer sus estados actuales y determinar los sectores con mayor deficiencia de servicio y que por ende no cumplían con los valores mínimos admitidos en la normativa de CNT EP. La implementación se realizó en el sector El Cisne conforme a la Normativa de diseño de Planta Externa con Plataformas de Acceso Exterior de CNT EP. Los resultados de la implementación permitieron tener un 91.27% de nivel de aceptación de la red con respecto a la resistencia de bucle, un 91.03% de aceptación con respecto a la atenuación y 95.29% respecto a al SNR, conforme a los establecido en la normativa vigente. Por lo tanto, la red de acceso implementada permite brindar QoS en el servicio de voz y datos para garantizar una reducción de gastos operativos, aumentar la competitividad, prestación de servicio eficiente a los clientes y cumplimiento de requisitos de la normativa de CNT EP. This paper details the efficient use and reuse of infrastructure through the migration from a traditional access network to a new network that implements VDSL / FTTX technology in order to improve telecommunications services in Guano city through CNT EP. The current state of FTTX networks that use VDSL technology was analyzed in order to establish the contribution for improving services in networks already implemented. On the other hand, measurements of electrical parameters (loop resistance, attenuation and signal noise) were carried out on 427 telephone networks in different sectors of Guano city to know their current states and decide the sectors with the greatest service deficiency and did not meet the minimum values allowed in the CNT EP regulations. The implementation was carried out in El Cisne sector in accordance with the External Plant Design Regulations with External Access Platforms for Network Deployment with VTL / FTTC Technology, by CNT EP. The results of the implementation showed 91.27% acceptance level of the loop resistance in the network, a 91.03% acceptance level of the attenuation and a 95.29% with respect to the signal noise, in accordance with the parameters established in the regulations. In conclusion, the access network with VDSL / FTTC technology implemented allows to provide QoS in the voice and data service in order to guarantee an efficient service to the clients and fulfilling all the requirements requested by the CNT EP. Palabras Claves: FTTC, VDSL, Fibra óptica, Atenuación, Resistencia de Bucle, SNR. Keywords: FTTC, VDSL, Fiber optic, Attenuation, Loop Resistance, SNR

    Criterios para evaluar metodologías de ensamblaje de objetos de aprendizaje

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    [ES]—La selección y secuenciación del material educativo digital es un trabajo que requiere de un esfuerzo importante por parte de docentes, especialistas, e incluso de estudiantes. Actualmente, se busca acompañar estas tareas a partir de procesos de ensamblaje de materiales educativos digitales, y en particular de objetos de aprendizaje. Se han comenzado a desarrollar metodologías y herramientas que soportan e implementan este proceso. Este trabajo propone profundizar en el análisis de las metodologías de ensamblaje de objetos de aprendizaje, que constituyen un tema de investigación y debate en la comunidad científica y académica. Para ello se aporta un conjunto de criterios de análisis para este tipo de metodologías, y se los aplica a una selección de 33 metodologías recopiladas. Este análisis ha permitido obtener resultados de interés en relación al estado del arte de estas estrategias de ensamblaje. En particular, se visualiza una tendencia en el desarrollo de sistemas automáticos o semiautomáticos para apoyar a docentes y alumnos en la creación de itinerarios de aprendizaje, y una baja cantidad de herramientas disponibles que implementen las metodologías revisadas. Los resultados y conclusiones de este trabajo abren las puertas para profundizar la investigación en la temática

    An AFM Approach of RBC Micro and Nanoscale Topographic Features During Storage

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    Blood gamma irradiation is the only available method to prevent transfusion-associated graft versus host disease (TA-GVHD). However, when blood is irradiated, determine blood shelf time is crucial. Non-irradiated blood has a self-time from 21 to 35 days when is preserved with an anticoagulated solution and stored at 4°C. During their storage, red blood cells (RBC) undergo a series of biochemical, biomechanical and molecular changes involving what is known as storage lesion (SL). SL include loss of structural integrity of RBC, a decrease of 2,3-diphosphatidylglyceric acid levels, and an increase of both ion potassium concentration and hemoglobin (Hb). On the other hand, Atomic force Microscopy (AFM) represents a versatile tool for a nano-scale high-resolution topographic analysis in biological systems. In order to evaluate SL in irradiated and non-irradiated blood, RBC topography and morphometric parameters were obtained from an AFM XE-BIO system. Cell viability was followed using flow cytometry. Our results showed that early markers as nanoscale roughness, allow us to evaluate blood quality since another perspective

    Creation and validation of a new tool for the monitoring efficacy of neurogenic bowel dysfunction treatment on response: the MENTOR tool

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    STUDY DESIGN: Prospective observational study. OBJECTIVES: A tool to help decision-making tool for Neurogenic Bowel Dysfunction (NBD) in individuals with SCI is needed. We present a project to create and validate a new tool, the Monitoring Efficacy of NBD Treatment On Response (MENTOR), and to determine its level of concordance with decisions made by experienced clinicians in the field. SETTING: UK, Denmark, USA, Italy, The Netherlands, Germany. METHODS: The first phase was creation of the tool through a modified Delphi process. The second phase was the validation, wherein individuals with spinal cord injury with NBD were asked to complete the MENTOR tool immediately prior to clinic consultation. From the responses to the questionnaire of the tool, each participant was allocated into one of three categories reflecting the possible therapeutic recommendations ("recommend change", "further discussion" and "monitoring"). An expert clinician then assessed the participant, blinded to MENTOR results, and made an independent treatment decision. RESULTS: A total of 248 MENTOR forms were completed. Strong agreement was found when the MENTOR tool recommended monitoring (92%) or treatment change (83%); the lowest concordance when the decision was for the "further discussion" option (59%). Patient acceptability was reported by 97% of individuals. CONCLUSIONS: MENTOR is an easy to use tool to monitor the treatment of NBD and determinate progression through the clinical pathway. This validation study shows good correspondence between expert clinician opinion and MENTOR result. The tool has potential to be used in other patient groups, following further studies

    Los clubes deportivos de natación de Cataluña en el actual contexto competitivo del sector de las instalaciones deportivas

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    Swimming clubs are non-profit entities for sports and social purposes. The general objective of the study was to know the management of swimming clubs in Catalonia, fulfilling their social and sports role in the current competitive environment of sports facilities. As specific objectives were to know their values on management indicators, as well as to know if significant differences between swimming clubs are found, taking in consideration their areas and sports offer. The study sample consists of 19 swimming clubs of Catalonia. The data collection instrument was a questionnaire adapted to the objectives of the study, administered by email to the managers of each club. The clubs obtain the necessary income to achieve their sporting and social goals thanks to the fees of their members. It was found significant differences between them according to the spaces and sports offer in different management indicators analyzed.Los clubes de natación son entidades sin ánimo de lucro con fines deportivos y sociales. El objetivo general del estudio fue conocer la gestión de los clubes de natación en Cataluña cumpliendo su función social y deportiva en el actual entorno competitivo de instalaciones deportivas. Los objetivos específicos fueron conocer sus valores en indicadores de gestión, así como saber si existen diferencias significativas entre los clubes según sus espacios y oferta deportiva. La muestra del estudio ha sido formada por 19 clubes deportivos de natación de Cataluña. El instrumento de recogida de datos fue un cuestionario adaptado a los objetivos del estudio, administrado por correo electrónico a los gerentes de cada club. Los clubes obtienen los ingresos necesarios para lograr sus fines deportivos y sociales gracias a las cuotas de sus socios. Se encontraron diferencias significativas entre ellos según los espacios y oferta deportiva en diferentes indicadores de gestión analizados

    Efficiency of the cerebroplacental ratio in Identifying high-risk late-term pregnancies

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    Background and Objectives: Over the last few years, great interest has arisen in the role of the cerebroplacental ratio (CPR) to identify low-risk pregnancies at higher risk of adverse pregnancy outcomes. This study aimed to assess the predictive capacity of the CPR for adverse perinatal outcomes in all uncomplicated singleton pregnancies attending an appointment at 40–42 weeks. Materials and Methods: This is a retrospective cohort study including all consecutive singleton pregnancies undergoing a routine prenatal care appointment after 40 weeks in three maternity units in Spain and the United Kingdom from January 2017 to December 2019. The primary outcome was adverse perinatal outcomes defined as stillbirth or neonatal death, cesarean section or instrumental delivery due to fetal distress during labor, umbilical arterial cord blood pH < 7.0, umbilical venous cord blood pH < 7.1, Apgar score at 5 min < 7, and admission to the neonatal unit. Logistic mixed models and ROC curve analyses were used to analyze the data. Results: A total of 3143 pregnancies were analyzed, including 537 (17.1%) with an adverse perinatal outcome. Maternal age (odds ratio (OR) 1.03, 95% confidence interval (CI) 1.01 to 1.04), body mass index (OR 1.04, 95% CI 1.03 to 1.06), racial origin (OR 2.80, 95% CI 1.90 to 4.12), parity (OR 0.36, 95% CI 0.29 to 0.45), and labor induction (OR 1.79, 95% CI 1.36 to 2.35) were significant predictors of adverse perinatal outcomes with an area under the ROC curve of 0.743 (95% CI 0.720 to 0.766). The addition of the CPR to the previous model did not improve performance. Additionally, the CPR alone achieved a detection rate of only 11.9% (95% CI 9.3 to 15) when using the 10th centile as the screen-positive cutoff. Conclusions: Our data on late-term unselected pregnancies suggest that the CPR is a poor predictor of adverse perinatal outcomes

    Confronting the loss of trophic support

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    Classic experiments with peripheral sympathetic neurons established an absolute dependence upon NGF for survival. A forgotten problem is how these neurons become resistant to deprivation of trophic factors. The question is whether and how neurons can survive in the absence of trophic support. However, the mechanism is not understood how neurons switch their phenotype to lose their dependence on trophic factors, such as NGF and BDNF. Here, we approach the problem by considering the requirements for trophic support of peripheral sympathetic neurons and hippocampal neurons from the central nervous system. We developed cellular assays to assess trophic factor dependency for sympathetic and hippocampal neurons and identified factors that rescue neurons in the absence of trophic support. They include enhanced expression of a subunit of the NGF receptor (Neurotrophin Receptor Homolog, NRH) in sympathetic neurons and an increase of the expression of the glucocorticoid receptor in hippocampal neurons. The results are significant since levels and activity of trophic factors are responsible for many neuropsychiatric conditions. Resistance of neurons to trophic factor deprivation may be relevant to the underlying basis of longevity, as well as an important element in preventing neurodegeneration

    Risk of miscarriage after chorionic villus sampling.

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    OBJECTIVE: To estimate the risk of miscarriage associated to chorionic villus sampling (CVS). METHODS: This was a retrospective cohort study performed in eight fetal-medicine units in Spain, Belgium and Bulgaria. Two populations were included: first, all singleton pregnancies attending to their first-trimester assessment in Murcia, Spain, and second, all singleton pregnancies having a CVS following first-trimester assessment at any of the participating centers. We used propensity score matching analysis to estimate the association between CVS and miscarriage. We compared risks of miscarriage of CVS and non-CVS groups after propensity score matching (1:1 ratio). This procedure creates two comparable groups balancing the maternal and pregnancy characteristics that lead to CVS, in a similar way in which randomization operates in a randomized clinical trial. RESULTS: The study population consisted of 22,250 participants in the non-CVS group and 3,613 in the CVS group. The incidence of miscarriage in the CVS group was 2.1% (77/3,613), which was significantly higher than the 0.9% (207/22,250) in the non-CVS group (p <0.001). The propensity score algorithm matched 2,122 CVS cases with 2,122 non-CVS cases including 40 (1.9%) and 55 (2.6%) miscarriages in the CVS and non-CVS groups, respectively (OR 0.72 [95% CI 0.48 to 1.10]; p = 0.146). However, we found a significant interaction between the CVS risk of miscarriage and the risk of aneuploidies, suggesting a different effect of the CVS for different baseline characteristics in such a way that, when the risk of aneuploidies is low, the risk after CVS increases (OR 2.87 [95% CI 1.13 to 7.30]) but when the risk is high, the risk after CVS is paradoxically reduced (OR 0.47 [95% CI 0.28 to 0.76]), presumably due to prenatal diagnosis and termination of major aneuploidies that would have otherwise resulted in spontaneous miscarriage. CONCLUSIONS: The risk of miscarriage in women having a CVS is about 1% higher than in women without CVS, although this excess risk is not entirely due to the invasive procedure but to some extent the demographic and pregnancy characteristics of the patient undergoing CVS. After accounting for these risk factors and confining the analysis to low-risk pregnancies, CVS seems to increase the risk of miscarriage about three times above the patient's background-risk. Although this is a substantial increase in relative terms, in pregnancies without risk factors, the risk of miscarriage after CVS will still remain low and similar to or slightly higher than that of the general population. For example, if her risk of aneuploidy is 1 in a 1,000 (0.1%), her risk of miscarriage after CVS will increase to 0.3% (0.2% higher)

    MAGESTIC: Magnetically Enabled Structures Using Interacting Coils

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    In our NIAC Phase I study, awarded September 2011, the MIT Space Systems Lab (MIT SSL) began investigating a new structural and mechanical technique aimed at reducing the mass and increasing the stowed-to-deployed ratio of spacecraft systems. This technique uses the magnetic fields from current passing through coils of high temperature superconductors (HTSs) to support spacecraft structures and deploy them to operational configurations from their positions as stowed inside a launch vehicle fairing. These electromagnetic coils are tethered or hinged together in such a way that their motion in some directions or around some axes is constrained, as in Figure 1. Our Phase II study,awarded in Fall 2012, continued this work on electromagnetic structures, with an added focus on developing a new thermal system, investigating additional, non-structural electromagnet functions, and creating a maturation roadmap and plan for addressing barriers to feasibility of the technology. We now call the project MAGESTIC, or Magnetically Enabled STructures using Interacting Coils

    Territorios Hidrosociales: una metodología para promover la seguridad hídrica ante el cambio climático a través de la gobernanza, visión y acción participativa

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    La gobernanza en territorios hidrosociales a partir de la participación ciudadana, el diálogo de saberes, y la confianza entre los actores territoriales es fundamental para garantizar una distribución justa y sostenible del agua. Este artículo presenta un enfoque metodológico para la promoción de la seguridad hídrica fundamentada en el fortalecimiento de la gobernanza del agua que permitan formalizar las aspiraciones de seguridad hídrica en la comunidad, la construcción de una visión y acciones estratégicas colectivas y concertadas. El enfoque integra conceptos pragmáticos y transdisciplinarios considerando sólo aquellos conceptos que proveen una explicación a partir de las perspectivas de actores independientemente de su disciplina, promueve la adaptación al cambio climático y la transformación hacia territorios sostenibles. La implementación de enfoques transdisciplinarios suele carecer de documentación, con este manuscrito se busca sistematizar como una oportunidad para promover la transparencia y la reproducibilidad de este tipo de iniciativas
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