820 research outputs found

    Evaluación – prueba de habilidades practica CCNA.

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    Evaluación – prueba de habilidades practica CCNA.En este trabajo se desarrolla la evaluación denominada “Prueba de habilidades prácticas”, forma parte de las actividades evaluativas del Diplomado de Profundización CCNA, y busca identificar el grado de desarrollo de competencias y habilidades que fueron adquiridas a lo largo del diplomado. Lo esencial es poner a prueba los niveles de comprensión y solución de problemas relacionados con diversos aspectos de Networking.In this work the evaluation called "Test of practical skills" is developed, it is part of the evaluation activities of the CCNA Deepening Diploma, and seeks to identify the degree of development of competences and skills that were acquired throughout the course. The essential thing is to test the levels of understanding and solving problems related to various aspects of Networking

    Functional Contribution of the Transcription Factor ATF4 to the Pathogenesis of Amyotrophic Lateral Sclerosis

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    Endoplasmic reticulum (ER) stress represents an early pathological event in amyotrophic lateral sclerosis (ALS). ATF4 is a key ER stress transcription factor that plays a role in both adaptation to stress and the activation of apoptosis. Here we investigated the contribution of ATF4 to ALS. ATF4 deficiency reduced the rate of birth of SOD1G86R transgenic mice. The fraction of ATF4−/−-SOD1G85R transgenic mice that were born are more resistant to develop ALS, leading to delayed disease onset and prolonged life span. ATF4 deficiency completely attenuated the induction of pro-apoptotic genes, including BIM and CHOP, and also led to quantitative changes in the ER protein homeostasis network. Unexpectedly, ATF4 deficiency enhanced mutant SOD1 aggregation at the end stage of the disease. Studies in the motoneuron cell line NSC34 demonstrated that knocking down ATF4 enhances mutant SOD1 aggregation possibly due to alteration in the redox status of the cell. Our results support a functional role of ATF4 in ALS, offering a novel target for disease intervention

    Reglas de combinación de los efectos de las tres componentes de terremotos y respuesta crítica

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    La precisión de las reglas de combinación del 30% y SRSS, y la orientación crítica de las componentes de terremotos se estudian en este trabajo. Se analizan modelos estructurales complejos que representan edificios de baja y mediana altura. Se realiza un análisis estadístico de la precisión de las reglas de combinación aplicadas a parámetros de respuesta individuales y múltiples. El efecto de la correlación entre las componentes de los terremotos en dicha precisión también se estudia. Finalmente, se realizan análisis con varios ángulos de incidencia de las componentes con la finalidad de encontrar la orientación crítica. Los resultados muestran que las reglas subestiman la carga axial en columnas, pero sobreestiman razonablemente los cortantes de entrepiso. Ambas reglas son más conservadoras cuando los modelos se excitan por las tres componentes. Los efectos individuales pueden estar altamente correlacionados, incluso para componentes principales no correlacionadas. Las reglas no siempre son precisas para valores pequeños de coeficientes de correlación, y valores altos de éstos no siempre están relacionados a una estimación imprecisa de la respuesta combinada. La precisión de las reglas de combinación depende del grado de correlación de las componentes, del parámetro de respuesta, de la localización del elemento considerado y del nivel de deformación estructural

    Late-life depression is able to accelerate learning and memory impairment in a mouse model of Alzheimer´s disease

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    Clinical studies suggest that depression could be considered an important risk factor for the future development of cognitive impairment and Alzheimer's disease (AD). In fact, there is a strong association between late-life depression and AD. The age of AD onset has been shown to be accelerated in patients with mild cognitive impairment (MCI) with a history of depression, and women appear to be particularly more vulnerable to this condition. In addition, individuals with MCI who present depressive symptoms have an elevated burden of amyloid-beta (Aβ), the main toxic protein associated with Alzheimer's pathology, and a higher risk of developing AD compared to non-depressed MCI patients. Although it has been described that some transgenic models of AD can develop signs similar to depression in advanced stages, the induction of Alzheimer's pathology due to a depressive process has not been studied under experimental conditions to emulate late-life depression as a risk factor for AD. The objective of this study is to determine, by inducing unpredictable mild chronic stress (CUMS) in tau transgenic P301S mice, whether depression is a cause, rather than a consequence, of AD development. The results of our study indicate that the induction of CUMS in transgenic animals induces phenotypic changes related to a depressive state. Behavioral and histological studies suggest that depression-like induction can worse AD pathology. The findings generated in this project could provide evidence of depression as a risk factor for AD

    Empirical Validation of a Class of Ray-Based Fading Models

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    As new wireless standards are developed, the use of higher operation frequencies comes in hand with new use cases and propagation effects that differ from the well-established state of the art. Numerous stochastic fading models have recently emerged under the umbrella of generalized fading conditions, to provide a fine-grain characterization of propagation channels in the mmWave and sub-THz bands. For the first time in literature, this work carries out an experimental validation of a class of such ray-based models, in a wide range of propagation conditions (anechoic, reverberation and indoor) at mmWave bands. We show that the independently fluctuating two-ray (IFTR) model has good capabilities to recreate rather dissimilar environments with high accuracy. We also put forth that the key limitations of the IFTR model arise in the presence of reduced diffuse propagation, and also due to a limited phase variability for the dominant specular components.Comment: 9 pages, 13 figure

    Aplicación móvil para la gestión de ventas de la empresa Mahpsa S.A.C., Lima, 2023

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    Las empresas inmobiliarias se dedican a la compra y venta de bienes inmuebles (casas, departamentos, comercios, terrenos, entre otros). Las inmobiliarias que no adoptan herramientas tecnológicas tienen dificultad para enfrentar desafíos en términos de eficiencia, competitividad y satisfacción del cliente. La incorporación de tecnología puede mejorar significativamente las oportunidades en el mercado. Por tal motivo, esta investigación tuvo por finalidad determinar en qué medida una aplicación móvil mejora la gestión de ventas de la empresa Mahpsa S.A.C., 2023. El estudio utilizó un enfoque cuantitativo y una metodología aplicada, con un diseño experimental preexperimental. La muestra consistió en 50 registros de ventas, y se aplicó la técnica de fichaje para la recopilación de datos, utilizando la ficha de registro validada por expertos y procesada con el software SPSS Statistics V.26. Los resultados mostraron un crecimiento del 31.44% al 60.24%, demostrando un aumento del 28.8%, en la tasa de captación de clientes (TCC). Además, se registró un incremento importante del 40.42% al 94.78%, con un aumento del 54.36%, en la tasa de resolución de consultas (TRC). En resumen, se determinó que la mejora en la gestión de ventas de la empresa Mhapsa se atribuye a la implementación de la aplicación móvil, lo cual ha influido positivamente en la estrategia comercial y ha elevado la satisfacción de los clientes

    Adaptive trajectory tracking control for quadrotors with disturbances by using generalized regression neural networks

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    In this document, the development and experimental validation of a nonlinear controller with an adaptive disturbance compensation system applied on a quadrotor are presented. The introduced scheme relies on a generalized regression neural network (GRNN). The proposed scheme has a structure consisting of an inner control loop inaccessible to the user (i.e., an embedded controller) and an outer control loop which generates commands for the inner control loop. The adaptive GRNN is applied in the outer control loop. The proposed approach lies in the aptitude of the GRNN to estimate the disturbances and unmodeled dynamic effects without requiring accurate knowledge of the quadrotor parameters. The adaptation laws are deduced from a rigorous convergence analysis ensuring asymptotic trajectory tracking. The proposed control scheme is implemented on the QBall 2 quadrotor. Comparisons with respect to a PD-based control, an adaptive model regressor-based scheme, and an adaptive neural-network controller are carried out. The experimental results validate the functionality of the novel control scheme and show a performance improvement since smaller tracking error values are produced.Fil: Lopez Sanchez, Ivan. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Rossomando, Francisco Guido. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Automática. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Automática; ArgentinaFil: Pérez Alcocer, Ricardo. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Soria, Carlos Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Automática. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Automática; ArgentinaFil: Carelli, Ricardo. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Automática; ArgentinaFil: Moreno Valenzuela, Javier. INSTITUTO POLITÉCNICO NACIONAL (IPN)
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