533 research outputs found

    El ensayo de solubilidad diferencial como método de caracterización de la estructura fina de las fibras químicas

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    La solubilidad diferencial es un ensayo físico-químico para la caracterización de la estructura fina de las fibras de poliéster, poliamida, acrílicas y fibras químicas de celulosa. En esta publicación se describe esta técnica, así como la influencia de las variables del ensayo. También se interpreta la curva de solubilidad diferencial vs. temperatura del ensayo. Por último, se citan ejemplos de campos de aplicación de este ensayo a diferentes grupos de sustratos de las mencionadas fibras

    Species distribution modeling in the tropics: problems, potentialities, and the role of biological data for effective species conservation

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    In this paper we aim to investigate the problems and potentialities of species distribution modeling (SDM) as a tool for conservation planning and policy development and implementation in tropical regions. We reviewed 123 studies published between 1995 and 2007 in five of the leading journals in ecology and conservation, and examined two tropical case studies in which distribution modeling is currently being applied to support conservation planning. We also analyzed the characteristics of data typically used for fitting models within the specific context of modeling tree species distribution in Central America. The results showed that methodological papers outnumbered reports of SDMs being used in an applied context for setting conservation priorities, particularly in the tropics. Most applications of SDMs were in temperate regions and biased towards certain organisms such as mammals and birds. Studies from tropical regions were less likely to be validated than those from temperate regions. Unpublished data from two major tropical case studies showed that those species that are most in need of conservation actions, namely those that are the rarest or most threatened, are those for which SDM is least likely to be useful. We found that only 15% of the tree species of conservation concern in Central America could be reliably modelled using data from a substantial source (Missouri Botanical Garden VAST database). Lack of data limits model validation in tropical areas, further restricting the value of SDMs. We concluded that SDMs have a great potential to support biodiversity conservation in the tropics, by supporting the development of conservation strategies and plans, identifying knowledge gaps, and providing a tool to examine the potential impacts of environmental change. However, for this potential to be fully realized, problems of data quality and availability need to be overcome. Weaknesses in current biological datasets need to be systematically addressed, by increasing collection of field survey data, improving data sharing and increasing structural integration of data sources. This should include use of distributed databases with common standards, referential integrity, and rigorous quality control. Integration of data management with SDMs could significantly add value to existing data resources by improving data quality control and enabling knowledge gaps to be identified

    Efecto de la refrigeración sobre la maduración del fruto del chirimoyo

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    Cherimoya fruits have a typically climateric ripening characterized, among other parameters, by a peak in the ethylene production that produces the senescence. Several attempts have been made in our Department in order to extend the shelf life of the fruits, but sorne undesirable reactions affecting the flavour are always produced. The most simple and natural treatment is the control of the storage temperature. With sorne precautions, it allows a considerable delay in the onset of senescence, making possible the marketing of the fruits in, previously, inaccessible markets.El fruto del chirimoyo presenta una maduración típicamente climatérica caracterizada, entre otros parámetros, por un pico muy acentuado de producción de etileno que conduce a la rápida senescencia. Varios intentos se han hecho en nuestro Departamento para tratar de prolongar la vida comercial de los frutos, pero en todos ellos se producen algunas reacciones indeseables que afectan a la palatabilidad. El tratamiento más natural es el control de la temperatura de almacenamiento, que con ciertas precauciones permite un retardo en la aparición de la senescencia, suficiente para alcanzar mercados de otra forma inaccesibles

    Efecto de la refrigeración sobre la maduración del fruto del chirimoyo

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    El fruto del chirimoyo presenta una maduración típicamente climatérica caracterizada, entre otros parámetros, por un pico muy acentuado de producción de etileno que conduce a la rápida senescencia. Varios intentos se han hecho en nuestro Departamento para tratar de prolongar la vida comercial de los frutos, pero en todos ellos se producen algunas reacciones indeseables que afectan a la palatabilidad. El tratamiento más natural es el control de la temperatura de almacenamiento, que con ciertas precauciones permite un retardo en la aparición de la senescencia, suficiente para alcanzar mercados de otra forma inaccesibles.Cherimoya fruits have a typically climateric ripening characterized, among other parameters, by a peak in the ethylene production that produces the senescence. Several attempts have been made in our Department in order to extend the shelf life of the fruits, but sorne undesirable reactions affecting the flavour are always produced. The most simple and natural treatment is the control of the storage temperature. With sorne precautions, it allows a considerable delay in the onset of senescence, making possible the marketing of the fruits in, previously, inaccessible markets

    Evolución de diversas actividades enzimáticas durante la maduración del chirimoyo n atmosfera controlada

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    Cherimoya fruits after harvesting have a short shelf life thus conditioning their marketing. Polyphenoloxidase, peroxidase, catalase and acid phosphatase are enzymes implicated in the ripening process of cherimoya. We have studied the variations of activity for these enzymes during cherimoya ripening in an C02 atmosphere and in the same atmosphere in presence sulphite. There was a marked decrease in the protein contents of both epicarp and mesocarp, during fruit ripening in C02 atmosphere. Enzymic activities also decreased at the beginning of the ripening. These low activities were maintained while fruits were in presence of C02 or C02 and sulphite.El fruto del chirimoyo tiene un proceso de maduración muy corto, lo cual afecta a su vida comercial. En este proceso están implicadas una serie de enzimas, como son polifenoloxidasa, peroxidasa, catalasa y fosfatasa ácida. Se han estudiado la evolución de las actividades de estas enzimas, almacenando los frutos en atmósfera de C02 y en presencia de sulfito. Los resultados obtenidos indican que existe una disminución en la concentración de proteínas totales, tanto en el epicarpio como en el mesocarpio de los frutos, durante la maduración en presencia de C02. Igualmente se produce una disminución de las actividades enzimáticas con este tratamiento. Esta baja actividad se mantiene, al menos durante tres semanas de almacenamiento. La presencia de sulfito en atmósfera de C02, no condiciona variaciones ni en la concentración de proteínas del fruto ni en las actividades enzimáticas

    ENFERMERÍA Y EDUCACIÓN PARA LA SALUD EN NUTRICIÓN ENTERAL DOMICILIARIA.

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    Home enteral nutrition (HEN) allows, besides guaranteeing a correct nutricional treatment, improving patient autonomy and wellbeing along with a reduction of the expenditure on hospitalization. Due to the characteristics of this treatment, which is administered at home, Health Education becomes of high importance: the patient, their family and/or caregivers need to learn theoretical and practical aspects of this procedure. For this reason, one of the nursing tasks could be not only the identification and treatment of its complications, but also being a patient/family educator.La nutrición enteral domiciliaria (NED) permite, además de garantizar un correcto tratamiento nutricional, favorecer la autonomía y el bienestar del paciente, junto con una reducción del coste sanitario por hospitalización. Debido al carácter domiciliario de esta terapéutica, adquiere especial importancia en este procedimiento la Educación para la Salud (EpS), que deberá manifestarse mediante un aprendizaje teórico-práctico al paciente, familia y/o cuidadores. Es por esto, que el profesional de Enfermería puede ser requerido para atender a este tipo de pacientes, no sólo desde el punto de vista asistencial, con la identificación y tratamiento de las complicaciones, sino por su papel de educador al paciente y a sus familiares

    Evolución de diversas actividades enzimáticas durante la maduración del chirimoyo en atmosfera controlada

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    El fruto del chirimoyo tiene un proceso de maduración muy corto, lo cual afecta a su vida comercial. En este proceso están implicadas una serie de enzimas, como son polifenoloxidasa, peroxidasa, catalasa y fosfatasa ácida. Se han estudiado la evolución de las actividades de estas enzimas, almacenando los frutos en atmósfera de C02 y en presencia de sulfito. Los resultados obtenidos indican que existe una disminución en la concentración de proteínas totales, tanto en el epicarpio como en el mesocarpio de los frutos, durante la maduración en presencia de C02. Igualmente se produce una disminución de las actividades enzimáticas con este tratamiento. Esta baja actividad se mantiene, al menos durante tres semanas de almacenamiento. La presencia de sulfito en atmósfera de C02, no condiciona variaciones ni en la concentración de proteínas del fruto ni en las actividades enzimáticas.Cherimoya fruits after harvesting have a short shelf life thus conditioning their marketing. Polyphenoloxidase, peroxidase, catalase and acid phosphatase are enzymes implicated in the ripening process of cherimoya. We have studied the variations of activity for these enzymes during cherimoya ripening in an C02 atmosphere and in the same atmosphere in presence sulphite. There was a marked decrease in the protein contents of both epicarp and mesocarp, during fruit ripening in C02 atmosphere. Enzymic activities also decreased at the beginning of the ripening. These low activities were maintained while fruits were in presence of C02 or C02 and sulphite

    XPO1 Gene Therapy Attenuates Cardiac Dysfunction in Rats with Chronic Induced Myocardial Infarction

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    Transcriptomic signature of XPO1 was highly expressed and inversely related to left ventricular function in ischemic cardiomyopathy patients. We hypothesized that treatment with AAV9-shXPO1 attenuates left ventricular dysfunction and remodeling in a myocardial infarction rat model. We induced myocardial infarction by coronary ligation in Sprague-Dawley rats (n = 10), which received AAV9-shXPO1 (n = 5) or placebo AAV9-scramble (n = 5) treatment. Serial echocardiographic assessment was performed throughout the study. After myocardial infarction, AAV9-shXPO1-treated rats showed partial recovery of left ventricular fractional shortening (16.8 +/- 2.8 vs 24.6 +/- 4.1%, P < 0.05) and a maintained left ventricular dimension (6.17 +/- 0.95 vs 4.70 +/- 0.93 mm, P < 0.05), which was not observed in non-treated rats. Furthermore, lower levels of EXP-1 (P < 0.05) and lower collagen fibers and fibrosis in cardiac tissue were observed. However, no differences were found in the IL-6 or TNFR1 plasma levels of the myocardium of AAV9-shXPO1 rats. AAV9-shXPO1 administration attenuates cardiac dysfunction and remodeling in rats after myocardial infarction, producing the gene silencing of XPO1

    Species distribution modeling in the tropics: problems, potentialities, and the role of biological data for effective species conservation

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    In this paper we aim to investigate the problems and potentialities of species distribution modeling (SDM) as a tool for conservation planning and policy development and implementation in tropical regions. We reviewed 123 studies published between 1995 and 2007 in five of the leading journals in ecology and conservation, and examined two tropical case studies in which distribution modeling is currently being applied to support conservation planning. We also analyzed the characteristics of data typically used for fitting models within the specific context of modeling tree species distribution in Central America. The results showed that methodological papers outnumbered reports of SDMs being used in an applied context for setting conservation priorities, particularly in the tropics. Most applications of SDMs were in temperate regions and biased towards certain organisms such as mammals and birds. Studies from tropical regions were less likely to be validated than those from temperate regions. Unpublished data from two major tropical case studies showed that those species that are most in need of conservation actions, namely those that are the rarest or most threatened, are those for which SDM is least likely to be useful. We found that only 15% of the tree species of conservation concern in Central America could be reliably modelled using data from a substantial source (Missouri Botanical Garden VAST database). Lack of data limits model validation in tropical areas, further restricting the value of SDMs. We concluded that SDMs have a great potential to support biodiversity conservation in the tropics, by supporting the development of conservation strategies and plans, identifying knowledge gaps, and providing a tool to examine the potential impacts of environmental change. However, for this potential to be fully realized, problems of data quality and availability need to be overcome. Weaknesses in current biological datasets need to be systematically addressed, by increasing collection of field survey data, improving data sharing and increasing structural integration of data sources. This should include use of distributed databases with common standards, referential integrity, and rigorous quality control. Integration of data management with SDMs could significantly add value to existing data resources by improving data quality control and enabling knowledge gaps to be identified
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