4,197 research outputs found
Propiedades mecánicas de películas híbridas (orgánico-inorgánico) sobre acero inoxidable 304
Este trabajo muestra la conformación de películas cerámicas del sistema híbridoSiO2 - TiO2-Polímero Orgánico, a partir de tetraetil-ortosilicato (Si (OC2H5)4), ytetra-butoxido de titanio (Ti(OBu)4) y sintetizado por el método sol-gel en diferentesconcentraciones volumétricas de los precursores. Este sistema híbrido se depositósobre sustratos de acero inoxidable AISI 304 mediante la técnica de inmersión (dipcoating).Se estudió la viabilidad de obtener recubrimientos híbridos homogéneossobre este tipo de sustrato y evaluar las propiedades superficiales. Para tal efecto, seestudió microdureza y adhesión del recubrimiento. Adicionalmente, se caracterizó lasuperficie de las películas por microscopía electrónica de barrido (MEB). Del estudiose concluye que las características de las películas cambian en función de la cantidadvolumétrica de los precursores utilizados en la conformación de las mismas
Digital filter implementation over FPGA platform with LINUX OS
AbstractThe embedded processors on FPGA's are a good tool to specific propose works. In this work we present how the FPGA is used to apply a Sobel filter to a set of images, also the step needed to set-up the entire system is described. An embedded processor, with a Linux distribution implemented is used to run a special compilation of C filter program, the filter is compared with the results obtained with a PC running the same filter, in the embedded system all the process runs in the FPGA and the exit file can be accessed by ftp or http server embedded into the Linux system
Propiedades mecánicas de películas híbridas (orgánico-inorgánico) sobre acero inoxidable 304
Este trabajo muestra la conformación de películas cerámicas del sistema híbridoSiO2 - TiO2-Polímero Orgánico, a partir de tetraetil-ortosilicato (Si (OC2H5)4), ytetra-butoxido de titanio (Ti(OBu)4) y sintetizado por el método sol-gel en diferentesconcentraciones volumétricas de los precursores. Este sistema híbrido se depositósobre sustratos de acero inoxidable AISI 304 mediante la técnica de inmersión (dipcoating).Se estudió la viabilidad de obtener recubrimientos híbridos homogéneossobre este tipo de sustrato y evaluar las propiedades superficiales. Para tal efecto, seestudió microdureza y adhesión del recubrimiento. Adicionalmente, se caracterizó lasuperficie de las películas por microscopía electrónica de barrido (MEB). Del estudiose concluye que las características de las películas cambian en función de la cantidadvolumétrica de los precursores utilizados en la conformación de las mismas
Síndrome das pernas inquietas : evolução após um ano sem tratamento
PURPOSE: The primary concern of this study is to evaluate the clinical course of restless legs syndrome (RLS) in a group of patients who refused treatment. METHOD: This study compares the outcome of a group of RLS patients after one year without any specific treatment. The International Restless Legs Syndrome Scale (IRLS) was applied at baseline (irls_1) and after one year (irls_2). The patients answered a simple questionnaire for the evaluation of possible environmental or life habit changes after one-year evolution. Serum ferritin was determined at baseline. An improvement index (%improvement) was established through the formula: irls_1– irls_2/irls_1 ' 100. Results were compared and a correlation analysis performed. RESULTS: A negative significant correlation was found between the patientsí age and irls_2 (r= –0.9 p=0.0018) and between %improvement and irls_2 (r= –0.88 p=0.0039). A positive and significant correlation was determined between %improvement and age. There was only a marginally significant correlation between serum ferritin and ilrs_2 (r= –0.7 p=0.052). No significant changes were found in the other elements analyzed. CONCLUSION: A favorable outcome was found in this group of RLS patients after one year evolution without treatment. The outcome was positively influenced by the patientsí age. ____________________________________________________________________________________________________________________ ABSTRACTOBJETIVO: O objetivo deste estudo é avaliar a evolução de oito pacientes com diagnóstico de síndrome das pernas inquietas (SPI) após doze meses sem tratamento. MÉTODO: Estudo de coorte, retrospectivo, consistindo na aplicação da escala de gravidade da SPI (IRLS), de questionário para avaliação de mudanças ambientais ou de hábitos de vida e dosagem de ferritina sérica. Realizada comparação da pontuação IRLS obtida na consulta inicial (irls_1) e após doze meses de evolução (irls_2) e estabelecido um índice de melhora percentual (%melhora=irls_1 – irls_2 / irls_1 ' 100). Análise de correlação dos dados obtidos.
RESULTADOS: Foi demonstrada correlação negativa e significativa entre a idade e a irls_2 (r= –0,9 e p=0,0018) e entre %melhora e irls_2 (r= –0,88 e p=0,0039). Encontrou-se correlação positiva e significativa entre %melhora e a idade. Houve apenas correlação negativa marginalmente não-significativa entre a dosagem de ferritina sérica e ilrs_2 (r= –0,7 e p=0,052). CONCLUSÃO: Neste grupo demonstrou-se evolução favorável da SPI após doze meses que se correlacionou positivamente com a idade dos pacientes, não tendo sido influenciada aparentemente por hábitos de vida ou mudanças ambientais
Serum Vitamin D Levels Are Not Predictive of the Progression of Chronic Liver Disease in Hepatitis C Patients with Advanced Fibrosis
In animal models and human cross-sectional studies, vitamin D deficiency has been associated with liver disease progression. Vitamin D supplementation has been suggested as a treatment to prevent disease progression. We sought to evaluate the role of vitamin D levels in predicting chronic liver disease development. We conducted a nested case-control study of vitamin D levels in subjects with (cases) and without (controls) liver histologic progression or clinical decompensation over the course of the HALT-C Trial. Vitamin D levels were measured at 4 points over 45 months. 129 cases and 129 aged-matched controls were included. No difference in baseline vitamin D levels were found between cases and controls. (44.8 ng/mL vs. 44.0 ng/mL, P = 0.74). Vitamin D levels declined in cases and controls over time (P = 0.0005), however, there was no difference in the level of decline (P = 0.37). Among study subjects with diabetes mellitius, baseline vitamin D levels were higher in cases, 49.9 ng/mL, than controls, 36.3 ng/mL. (P = 0.03) In addition, baseline vitamin D levels were higher in black case subjects, 32.7 ng/mL, than in black control subjects, 25.2 ng/mL (P = 0.08) No difference in vitamin D levels was found between patients with and without progression of hepatitis C-associated liver disease over 4 years. Our data do not suggest any role for vitamin D supplementation in patients with advanced chronic hepatitis C and raise the possibility that higher vitamin D levels may be associated with disease progression
Una aplicación del muestreo aleatorio simple para la caracterización elemental de residuos sólidos en la industria
Una planta industrial colombiana genera residuos sólidos como subproducto de su proceso. En la actualidad estos residuos se están disponiendo inadecuadamente, aunque se cree que podrían ser utilizados, al menos parcialmente, como materias primas en otros procesos. Este artículo se refiere en particular al procedimiento para elegir muestras de los diferentes residuos sólidos del proceso, para su posterior caracterización, la cual conducirá a identificar sus usos potenciales o recomendará su adecuada disposición. Se analizan los resultados del análisis elemental y se evalúa el plan de muestreo aplicado para lograr esta caracterización
Una aplicación del muestreo aleatorio simple para la caracterización elemental de residuos sólidos en la industria
Una planta industrial colombiana genera residuos sólidos como subproducto de su proceso. En la actualidad estos residuos se están disponiendo inadecuadamente, aunque se cree que podrían ser utilizados, al menos parcialmente, como materias primas en otros procesos. Este artículo se refiere en particular al procedimiento para elegir muestras de los diferentes residuos sólidos del proceso, para su posterior caracterización, la cual conducirá a identificar sus usos potenciales o recomendará su adecuada disposición. Se analizan los resultados del análisis elemental y se evalúa el plan de muestreo aplicado para lograr esta caracterización
Expression and localization of the polarity protein CRB2 in adult mouse brain: a comparison with the CRB1rd8 mutant mouse model
Acquisition of cell polarization is essential for the performance of crucial functions, like a successful secretion and appropriate cell signaling in many tissues, and it depends on the correct functioning of polarity proteins, including the Crumbs complex. The CRB proteins, CRB1, CRB2 and CRB3, identified in mammals, are expressed in epithelial-derived tissues like brain, kidney and retina. CRB2 has a ubiquitous expression and has been detected in embryonic brain tissue; but currently there is no data regarding its localization in the adult brain. In our study, we characterized the presence of CRB2 in adult mice brain, where it is particularly enriched in cortex, hippocampus, hypothalamus and cerebellum. Double immunofluorescence analysis confirmed that CRB2 is a neuron-specific protein, present in both soma and projections where colocalizes with certain populations of exocytic and endocytic vesicles and with other members of the Crumbs complex. Finally, in the cortex of CRB1rd8 mutant mice that contain a mutation in the Crb1 gene generating a truncated CRB1 protein, there is an abnormal increase in the expression levels of the CRB2 protein which suggests a possible compensatory mechanism for the malfunction of CRB1 in this mutant background.This study was supported by Fondo de Investigaciones Sanitarias Instituto Carlos III (PI15/01240), co-funded by European Union (ERDF/ESF, “Investing in your future”) to C.L. A. Velasco, R. Arévalo and C. Lillo are members of the UIC.077 from Junta de Castilla y León
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