103 research outputs found

    EPIDEMIOLOGÍA, EL DISCURRIR DEL ESTADO DE SALUDENFERMEDAD

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    Aunque muchos indicadores de la calidad de vida se handesarrollado entre las personas de sociedadespreindustriales, industriales y postindustriales, uno de losmás importantes es el estado de salud de la población.El estado de salud no solo se une estrechamente al nivelde desarrollo industrial de un país, sino también a laedad y composición de genero de las personas, a ladistribución de la riqueza y el poder. Las enfermedades ypadecimientos, incluso las de origen mental, no sedistribuyen al azar en la población. Más bien, de unaforma irregular por edad, sexo, clase social, lugar deresidencia, origen, factor étnico, ocupación y hábitoscomo fumar o/y beber

    Spatial Atomic Layer Deposition

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    In conventional atomic layer deposition (ALD), precursors are exposed sequentially to a substrate through short pulses while kept physically separated by intermediate purge steps. Spatial ALD (SALD) is a variation of ALD in which precursors are continuously supplied in different locations and kept apart by an inert gas region or zone. Film growth is achieved by exposing the substrate to the locations containing the different precursors. Because the purge step is eliminated, the process becomes faster, being indeed compatible with fast-throughput techniques such as roll-to-roll (R2R), and much more versatile and easier and cheap to scale up. In addition, one of the main assets of SALD is that it can be performed at ambient pressure and even in the open air (i.e., without using any deposition chamber at all), while not compromising the deposition rate. In the present chapter, the fundamentals of SALD and its historical development are presented. Then, a succinct description of the different engineering approaches to SALD developed to date is provided. This is followed by the description of the particular fluid dynamics aspects and the engineering challenges associated with SALD. Finally, some of the applications in which the unique assets of SALD can be exploited are described

    Chapter Spatial Atomic Layer Deposition

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    In conventional atomic layer deposition (ALD), precursors are exposed sequentially to a substrate through short pulses while kept physically separated by intermediate purge steps. Spatial ALD (SALD) is a variation of ALD in which precursors are continuously supplied in different locations and kept apart by an inert gas region or zone. Film growth is achieved by exposing the substrate to the locations containing the different precursors. Because the purge step is eliminated, the process becomes faster, being indeed compatible with fast-throughput techniques such as roll-to-roll (R2R), and much more versatile and easier and cheap to scale up. In addition, one of the main assets of SALD is that it can be performed at ambient pressure and even in the open air (i.e., without using any deposition chamber at all), while not compromising the deposition rate. In the present chapter, the fundamentals of SALD and its historical development are presented. Then, a succinct description of the different engineering approaches to SALD developed to date is provided. This is followed by the description of the particular fluid dynamics aspects and the engineering challenges associated with SALD. Finally, some of the applications in which the unique assets of SALD can be exploited are described

    Ru- and Ir-complex decorated periodic mesoporous organosilicas as sensitizers for artificial photosynthesis

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    A versatile and facile strategy based on an inverse electron demand Diels–Alder reaction between 5-norbornen-2-yltriethoxysilane and a tetrazine derivative has been established for the synthesis of a new triethoxysilane precursor containing dipyridylpyridazine units. Such a precursor has been incorporated into the mesostructure of an ethylene-bridged periodic mesoporous organosilica (PMO) material through a one-pot synthesis via a co-condensation method. Upon attachment of Ru- and Ir-complexes to the pendant N-chelating heterocyclic ligands, the resulting decorated PMOs have acted as photosensitizers in artificial photosynthetic systems. The deposition of Pt on these PMOs has allowed us to obtain efficient photocatalytic materials for the hydrogen evolution reaction as a result of electron transfer from the light harvesting Ru- and Ir-complexes to the supported Pt nanoparticles through methyl viologen as an electron relay. They have exhibited total turnover number values of 573 and 846, respectively, under visible light irradiation. The role played by each component and the stability of the photocatalytic systems have been discussed. The present approach paves the way to the synthesis of different materials with coordination sites capable of forming surface complexes to be applied as sensitizers and catalysts

    Guía práctica para coocrear comunidades socioeducativas mediante el uso de la permacultura, la pintura y el teatro: los trece senderos del aprendizaje: espirales madre, aplicación de la permacultura [TOMO 2]

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    En el marco de los proyectos, gestionados por estudiantes, de Iniciativas Estudiantiles de Acción Social de la Vicerrectoría de Acción Social de la Universidad de Costa Rica, 2014-2015. El siguiente material aborda las vivencias, saberes, guías, conocimientos, compartidos entre los estudiantes y las comunidades costarricenses fomentando un vinculo entre la sociedad y la universidad pública. Específicamente se llevó a cabo en la comunidad aledaña a la Sede de Occidente de la Universidad de Costa Rica en San Ramón de Alajuela, por la iniciativa: IE-32 Coocreando comunidades socioeducativas por medio de la permacultura, el teatro, la música y pintura: hacia una cultura de redes para el intercambio local. Utilizando como medios lúdico-pedagógicos la permacultura, la pintura y el teatro para la sistematización del proceso y así generar una guía que pueda ser utilizada para replicar la experiencia o sirva de insumo en el desarrollo de experiencias e iniciativas similares. También, se plasmó un relato narrativo sobre la Espiral Madre y los trece senderos de la permacultura, que explica el proceso de la agricultura alternativa orgánica, amigable con el medio ambiente y socialmente responsable.UCR::Vicerrectoría de Acción Social::Iniciativas Estudiantiles de Acción Socia

    Validity of the Isometric Contraction Test of the Masticatory Muscles for Diagnosis of Muscular Temporomandibular Disorders

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    In recent years, the Diagnostic Criteria for Temporomandibular Pain Disorders (DC/TMD) has been questioned, mainly because of the dependence on the muscular pressure needed to be applied during the clinical examination. Therefore, it is necessary to establish improvements in diagnostic strategies for DC/TMD of axis I. The aim of this study was to determine the validity of the Isometric Contraction Test of the masticatory muscles (ICTest) to diagnose DC/TMD of axis I. Forty (n = 40) patients with muscular TMD (myalgia in any of its subtypes), as well as forty age and sex matched controls, participated. They were diagnosed according to DC/TMD of axis I and performed the ICTest in a single session. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and positive (LR+) and negative likelihood ratios (LR−) of the ICTest compared with the DC/TMD of axis I were calculated. The ICTest showed a specificity of 95% for the diagnosis of myalgia, and between 94.9% and 96.8% for all subtypes in relation to the DC/TMD of axis I. For sensitivity, lower values were obtained, that is, 90.0% for myalgia, and losing sensitivity depending on the type of myalgia. The LR+ was over 10 for all diagnoses, with the exception of myofascial pain with referral, which was lower. When addressing the LR−, the myofascial diagnosis was the only one below 0.2. According to the results, the ICTest could be considered a valid procedure to diagnose subjects with muscular TMD in a clinical setting

    Short-term exposure to benzalkonium chloride in bacteria from activated sludge alters the community diversity and the antibiotic resistance profile

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    The continuous introduction of cleaning products containing benzalkonium chloride (BAC) from household discharges can mold the microbial communities in wastewater treatment plants (WWTPs) in a way still poorly understood. In this study, we performed an in vitro exposure of activated sludge from a WWTP in Costa Rica to BAC, quantified the changes in intI1, sul2, and qacE/qacEΔ1 gene profiles, and determined alterations in the bacterial community composition. The analysis of the qPCR data revealed elevated charges of antibiotic resistance genes in the microbial community; after BAC’s exposure, a significant increase in the qacE/qacEΔ1 gene, which is related to ammonium quaternary resistance, was observed. The 16S rRNA gene sequences’ analysis showed pronounced variations in the structure of the bacterial communities, including reduction of the alpha diversity values and an increase of the relative abundance of Alphaproteobacteria, particularly of Rhodospseudomonas and Rhodobacter. We confirmed that the microbial communities presented high resilience to BAC at the mg/mL concentration, probably due to constant exposure to this pollutant. They also presented antibiotic resistance-related genes with similar mechanisms to tolerate this substance. These mechanisms should be explored more thoroughly, especially in the context of high use of disinfectant.Universidad de Costa Rica/[]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

    Soroprevalência da toxocaríase humana em três comunidades andinas do Nordeste de Lima, Peru

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    The aim of this study was to assess the seroprevalence of human toxocariasis in three Andean communities from the Northeast of Lima, Peru. A total of 303 subjects including children and adults were studied and blood samples were collected to detect anti-Toxocara antibodies by ELISA-IgG test and by hematological examination; stool samples were collected also for parasitological examination. The overall seroprevalence of toxocariasis observed in the total population was 20.46%, with a significant high proportion in children from one to 10 years old (p = 0.034). Among the subjects with positive serology, 32.26% of them had respiratory disturbances, 22.58% hepatomegaly, 17.74% ocular signs or symptoms, 14.51% abdominal pain, 9.68% neurological involvement, and 4.84% cutaneous signs, but none of these clinical features were associated to a positive serology by multivariate analysis. Furthermore, 79.03% of seropositive subjects also harbored at least one intestinal parasite, which was associated to a positive serology (p < 0.05). The presence of pets within the houses, a previous history of pica or geophagia and the use of public places were also present in this population, but only the latter was associated to the serology (p < 0.05). In conclusion, clinical, serological, and epidemiological evidences for larval Toxocara infection were found in the studied population.O propósito do presente trabalho foi estimar a soroprevalência da toxocaríase humana em três comunidades andinas do Nordeste de Lima, Peru. Foi estudado um total de 303 pessoas, entre crianças e adultos. Foram coletadas amostras de sangue para a detecção de anticorpos anti-Toxocara e para a análise hematológica, além de amostras fecais para o exame parasitológico. A soroprevalência geral da população foi de 20,46% com proporção significativamente maior de positividade em crianças de um a 10 anos (p = 0,034). Das pessoas com sorologia positiva, 32,26% apresentavam sintomas respiratórios, 22,58% moléstias hepáticas, 17,74% manifestações oculares, 14,51% dor abdominal, e 4,84% sinais cutâneos. Além disso, 79,03% das pessoas com sorologia positiva tinham pelo menos algum parasito intestinal com associação significativa (p < 0.05). A presença de cachorros dentro das casas, história de pica ou geofagia e o uso dos lugares públicos também estiveram presentes nesta população, mas o ultimo deles só esteve associado com a sorologia positiva (p < 0.05). Conclui-se que existem evidências clínicas, sorológicas e epidemiológicas de infecção por larvas de Toxocara na população estudada
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