414 research outputs found

    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

    Variaciones climáticas en la Zona Metropolitana de la Ciudad de Toluca, Estado de México: 1960-2007

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    Los científicos del Panel Intergubernamental para el Cambio Climático (ipcc, 2001), han analizado las posibles consecuencias que pueden representar los cambios climáticos en distintos espacios geográficos de la Tierra. En México, el cambio climático empieza a ser notorio, por esta razón se realizó una investigación en la Zona Metropolitana de la Ciudad de Toluca y su hinterland para estudiar el comportamiento de la temperatura y la precipitación entre 1960 y 2007, y demostrar la existencia de variaciones que pueden contribuir al cambio climático. El sustento teórico de esta investigación fue la geografía ambiental, y el metodológico se basó en la estadística, trabajo de campo, el método comparativo y la cartografía automatizada. Con los resultados obtenidos se puede concluir que el clima en la zmct y su hinterland están en proceso de cambio y, de acuerdo con las investigaciones e informes de la nasa y el ipcc, éste seguirá cambiando globalmente.Los cientíÀcos del Panel Intergubernamental para el Cambio Climático (ipcc, 2001), han analizado las posibles consecuencias que pueden representar los cambios climáticos en distintos espacios geográÀcos de la Tierra. En México, el cambio climático empieza a ser notorio, por esta razón se realizó una investigación en la Zona Metropolitana de la Ciudad de Toluca y su hinterland para estudiar el comportamiento de la temperatura y la precipitación entre 1960 y 2007, y demostrar la existencia de variaciones que pueden contribuir al cambio climático. El sustento teórico de esta investigación fue la geografía ambiental, y el metodológico se basó en la estadística, trabajo de campo, el método comparativo y la cartografía automatizada. Con los resultados obtenidos se puede concluir que el clima en la zmct y su hinterland están en proceso de cambio y, de acuerdo con las investigaciones e informes de la nasa y el ipcc, éste seguirá cambiando globalmente

    Calidad de vida universitaria: identificación de los principales indicadores de satisfacción estudiantil

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    La eficacia de los sistemas internos de calidad universitarios se ve mejorada cuando estos incorporan información referente al estudiante, concretamente, el grado de satisfacción con la vida universitaria. Para ello, se requiere identificar las variables que más valoran los estudiantes y, a partir de estas, establecer los indicadores pertinentes. Este artículo tiene como objetivo principal contribuir a la construcción de un sistema interno de garantía de calidad, mediante la identificación de indicadores relevantes en la calidad de vida universitaria conforme a su percepción. Partiendo del modelo propuesto por Sirgy, Grezeskowiak y Rahtz (2007) se mide la calidad de vida universitaria (CVU) mediante el estudio de la satisfacción de los estudiantes y se contrasta empíricamente en la Facultad de Ciencias Sociales de Talavera de la Reina (Universidad de Castilla-La Mancha) durante el curso académico 2010-11. Para ello se realizan encuestas online a los alumnos que cursan estudios de Administración de Empresa. Los datos obtenidos se tabulan desarrollando un modelo de ecuaciones estructurales que nos permite identificar aquellos elementos que influyen de manera significativa en la satisfacción de los alumnos respecto a tres aspectos: recursos e instalaciones, aspectos docentes y aspectos sociales. Los resultados obtenidos muestran que tanto los aspectos académicos como los sociales son dimensiones influyentes en la satisfacción de los alumnos. La docencia y la reputación académica son las variables académicas más influyentes; por su parte, las actividades deportivas y los programas internacionales son los aspectos sociales con mayor impacto en la satisfacción estudiantil. Con estos resultados podemos establecer que el desarrollo de programas de calidad universitaria, en sus sistemas internos de garantía de calidad, debe atender a los aspectos sociales en una magnitud similar al desarrollo de los aspectos académicos

    Velocidad media de infiltración en un vertisol bajo distintos sistemas de labranza

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    Soil compaction is regarded as the most serious environmental problem caused by conventional agriculture. Few studies are concerned with the assessment of soil compaction using infiltration speed, specifically in the Vertisol soil characteristic of the main maize producing area of the Toluca-Atlacomulco Valley in central Mexico. The aim of this research was to examine the effect on infiltration speed and penetration resistance of a Vertisol soil when compacted by wheeled agricultural traffic in three different types of tillage systems: zero, minimal and conventional. Penetration resistance was measured on the wheel track with a portable digital penetrometer, and the mean infiltration speed was determined according to the double cylinder infiltrometer method. The pressure exerted by the number of wheeled traffic passes increased Vertisol soil compaction at 30 cm depth. Even though the benefits of zero tillage were similar to those showed by mínimum tillage during the experimental period, minimum tillage reported the highest infiltration spee

    Industrial development of beef and pork cecina with different flavors

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    Cecina used traditional technique for salting and preserving meat as well as to impart flavor; however, addition of spices is a viable alternative to diversify the flavors of the product. The objective of this research was to develop beef and pork cecina of flavors and evaluate lipid oxidation after 30 days of storage. Beef and pork cecina were distributed independently in four treatments: Formulation 1 or base (10.7% salt, 1.3% sugar, 0.5% nitrite and seasoning 0.1%); formulation 2, base plus 10 g of mixture of coriander, celery, parsley dehydrated/kg meat; formulation 3, base plus 10 g dry mirasol chilli/kg of meat and liquid smoke (2 mL/L) and formulation 4, base plus 0.80 mL of essential oregano oil/L. Beef cecina was dried at 80 °C for 150 minutes and pork cecina for 180 minutes until these achieved a water activity (aw) of 0.75. Beef cecina was packaged in cellophane bag, while for pork cecina in vacuum bags. Lipid oxidation was determined using thiobarbituric acid test (TBA). The results revealed that only beef cecina presented fat rancidity

    Description of small and large-scale cross laminated timber fire tests

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    A large-scale fire test was conducted on a compartment constructed from cross laminated timber (CLT). The internal faces of the compartment were lined with non-combustible board, with the exception of one wall and the ceiling where the CLT was exposed directly to the fire inside the compartment. Extinction of the fire occurred without intervention. During the fire test, measurements were made of incident radiant heat flux, gas phase temperature, and in-depth temperature in the CLT. In addition, gas flow velocities and gas phase temperatures at the opening were measured, as well as incident heat fluxes at the facade due to flames and the plume leaving the opening. The fuel load was chosen to be sufficient to attain flashover, to achieve steady-state burning conditions of the exposed CLT, but to minimize the probability of uncertain behaviors induced by the specific characteristics of the CLT. Ventilation conditions were chosen to approximate maximum temperatures within a compartment. Wood cribs were used as fuel and, following decay of the cribs, self-extinction of the exposed CLT rapidly occurred. In parallel with the large-scale test, a small scale study focusing on CLT self-extinction was conducted. This study was used to establish: the range of incident heat fluxes for which self-extinction of the CLT can occur; the duration of exposure after which steady-state burning occurred; and the duration of exposure at which debonding of the CLT could occur. The large-scale test is described, and the results from both the small and large-scale tests are compared. It is found that self-extinction occurred in the large-scale compartment within the range of critical heat fluxes obtained from the small scale tests

    On the evolution of “cleaner production” as a concept and a practice

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    “Cleaner Production“(CP) is about less and more efficient energy and materials use and the substitution of more harmful products (for the environment and health) by less dangerous ones. CP was the reply of the industry to the call for sustainable development as launched by the WCED (1987) and further elaborated in Rio's Agenda 21 (UN, 1992). During the past 25 years, the concept was put in practice. During this period it changed in scope, methods, and application area. This provided a deeper socio-economic impact to an idea that was originally launched to awaken industry on its environmental responsibilities. This paper provides a review of essentials that contributed to the fundamental changes in CP during the most recent quarter of a century. It takes off with a review of CP definitions illustrating the changes of the content. Changes in scope are exemplified with the increasing importance of “Corporate Social Responsibility” (CSR). This includes that post-modern companies have not only responsibilities on their economic performance and the environment, but should also act on issues including human rights and resources, business ethics, and community involvement. The links between CP and green and circular economy are indicated. The CP approach is increasingly applied outside the industry. CP for sustainable tourism is discussed in more detail but is only an example of the wider application in e.g. agriculture or health services

    Analysis of TNFAIP3, a feedback inhibitor of nuclear factor-κB and the neighbor intergenic 6q23 region in rheumatoid arthritis susceptibility

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    Introduction Genome-wide association studies of rheumatoid arthritis (RA) have identified an association of the disease with a 6q23 region devoid of genes. TNFAIP3, an RA candidate gene, flanks this region, and polymorphisms in both the TNFAIP3 gene and the intergenic region are associated with systemic lupus erythematosus. We hypothesized that there is a similar association with RA, including polymorphisms in TNFAIP3 and the intergenic region. Methods To test this hypothesis, we selected tag-single nucleotide polymorphisms (SNPs) in both loci. They were analyzed in 1,651 patients with RA and 1,619 control individuals of Spanish ancestry. Results Weak evidence of association was found both in the 6q23 intergenic region and in the TNFAIP3 locus. The rs582757 SNP and a common haplotype in the TNFAIP3 locus exhibited association with RA. In the intergenic region, two SNPs were associated, namely rs609438 and rs13207033. The latter was only associated in patients with anti-citrullinated peptide antibodies. Overall, statistical association was best explained by the interdependent contribution of SNPs from the two loci TNFAIP3 and the 6q23 intergenic region. Conclusions Our data are consistent with the hypothesis that several RA genetic factors exist in the 6q23 region, including polymorphisms in the TNFAIP3 gene, like that previously described for systemic lupus erythematosus
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