449 research outputs found

    Arquitectura de la información: el diseño de los espacios y flujos de información en la World Wide Web

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    Vulnerability of Mesostriatal Dopaminergic Neurons in Parkinson's Disease

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    The term vulnerability was first associated with the midbrain dopaminergic neurons 85 years ago, before they were identified as monoaminergic neurons, when Foix and Nicolesco (1925) reported the loss of neuromelanin containing neurons in the midbrain of patients with post-encephalitic Parkinson's disease (PD). A few years later, Hassler (1938) showed that degeneration is more intense in the ventral tier of the substantia nigra compacta than in its dorsal tier and the ventral tegmental area (VTA), outlining the concept of differential vulnerability of midbrain dopaminergic (DA-) neurons. Nowadays, we know that other neuronal groups degenerate in PD, but the massive loss of nigral DA-cells is its pathological hallmark, having a pivotal position in the pathophysiology of the disease as it is responsible for the motor symptoms. Data from humans as well as cellular and animal models indicate that DA-cell degeneration is a complex process, probably precipitated by the convergence of different risk factors, mediated by oxidative stress, and involving pathogenic factors arising within the DA-neuron (intrinsic factors), and from its environment and distant interconnected brain regions (extrinsic factors). In light of current data, intrinsic factors seem to be preferentially involved in the first steps of the degenerative process, and extrinsic factors in its progression. A controversial issue is the relative weight of the impairment of common cell functions, such as energy metabolism and proteostasis, and specific dopaminergic functions, such as pacemaking activity and DA handling, in the pathogenesis of DA-cell degeneration. Here we will review the current knowledge about the relevance of these factors at the beginning and during the progression of PD, and in the differential vulnerability of midbrain DA-cells

    Personal Employability and employment outcomes in a university sample: a study before and after COVID-19

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    [EN] Labour market uncertainty makes difficult to get (and keep) a high-quality job even for graduate students. Moreover, this situation has been worsened due to the COVID-19 pandemic. The aim of this study is to test the influence that personal employability has on maintaining (or being able to find a new) high-quality job in a sample of young university graduates that faced the job market crisis caused by the COVID-19 pandemic. We focus on the four personal employability dimensions of Fugate et al.’s (2004) model: career identity, personal adaptability, human capital, and social capital. Our hypotheses state that the four dimensions of employability are positively related with employment status and with job quality indicators (salary, horizontal fit, job satisfaction). The results obtained in a sample of 136 university graduates show that social capital contributes to being employed after several months of job market uncertainty caused by COVID-19. Moreover, career identity positively predicts horizontal fit and job satisfaction. The study shows the importance of social capital and career identity under uncertain job market situations to foster positive employment outcomes.This work was supported by research grants provided by the Spanish Ministry of Economy and Competitiveness (MINECO), the Spanish State Research Agency (AEI), and the European Regional Development Fund (ERDF) [Ref. PSI2017-86882-R].Hernández, A.; Tomás, I.; Davcheva, M.; González-Romá, V. (2021). Personal Employability and employment outcomes in a university sample: a study before and after COVID-19. En 7th International Conference on Higher Education Advances (HEAd'21). Editorial Universitat Politècnica de València. 1303-1311. https://doi.org/10.4995/HEAd21.2021.13131OCS1303131

    Remarks on the daily rhythm of Lepidoptera in Simsia amplexicaulis (Cav.) (Asteraceae) in a cloud forest of Veracruz State, Mexico

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    A total of 424 Lepidoptera specimens (256 males, 168 females) visiting flower patches of Simsia amplexicaulis were collected. They were found to belong to six families within three superfamilies representing a total of 23 species: Papilionoidea: Pieridae (2 species), Lycaenidae (1 species), Riodinidae (2 species), Nymphalidae (6 species); Hesperioidea: Hesperiidae (11 species); and Noctuoidea: Erebidae (1 species). The temporal distribution of these lepidopterans shows a peak of species visiting a patch of flowers between 12:00 and 13:00. Twenty five of the species (93%) were recorded during such activity hourly peak while only two species were found visiting the flowers during most of the day. Twenty species (74%) visited the flowers only once. As far as we know, this is the first time that Cuanopepla bella (Ctenuchidae) is reported visiting flowers of Simsia amplexicaulis

    The effect of motor activity on improved memory andemotional well-being in elderly women

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    p. 20-32Este estudio investiga el efecto de diversos tipos de intervención (cognitiva versus cognitiva + motora versus no intervención) en la memoria y el estado de ánimo emocional en mujeres mayores con quejas de memoria y con una vida pasiva. Los sujetos (N=102, 80% mujeres, edad M/SD = 76/5 años) se distribuyeron de forma aleatoria en los tres grupos de tratamiento. El entrenamiento cognitivo consistió en ejercicios de atención, lenguaje, asociación de ideas y resolución de problemas. El entrenamiento motor consistió en ejercicios propioceptivos y dinámicos relacionados con el esquema corporal, el equilibrio y la coordinación de movimientos. La intervención se llevó a cabo durante 8 meses. Se aplicaron el Test Conductual de Memoria Rivermead (RBMT) y la Escala Geriátrica de Depresión de Yesavage (GDS) antes y después. Los resultados demuestran mejorías asociadas a ambas intervenciones y deterioro en el grupo de control. Sin embargo, sólo el grupo de intervención cognitiva-motora muestra una mejoría relevante según las pruebas citadas. Los resultados sugieren que la intervención combinada cognitiva-motora es más prometedora que la intervención simplemente cognitiva para mejorar la función de la memoria y del estado de ánimo en mujeres con pérdidas de memoria subjetivas, y que las dos son eficaces en comparación con la no intervenciónS

    Montfort, obres hidràuliques disperses

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    Les comarques del Vinalopó tenen moltes obres hidràuliques de origen musulmá i de tradició cristiana que es mantenen en l'actualitat com el cas de Montfort d'Alacant

    Examination of the Feynman-Hibbs Approach in the Study of NeN_N-Coronene Clusters at Low Temperatures

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    Feynman-Hibbs (FH) effective potentials constitute an appealing approach for investigations of many-body systems at thermal equilibrium since they allow us to easily include quantum corrections within standard classical simulations. In this work we apply the FH formulation to the study of NeN_N-coronene clusters (N=N= 1-4, 14) in the 2-14 K temperature range. Quadratic (FH2) and quartic (FH4) contributions to the effective potentials are built upon Ne-Ne and Ne-coronene analytical potentials. In particular, a new corrected expression for the FH4 effective potential is reported. FH2 and FH4 cluster energies and structures -obtained from energy optimization through a basin-hoping algorithm as well as classical Monte Carlo simulations- are reported and compared with reference path integral Monte Carlo calculations. For temperatures T>4T> 4 K, both FH2 and FH4 potentials are able to correct the purely classical calculations in a consistent way. However, the FH approach fails at lower temperatures, especially the quartic correction. It is thus crucial to assess the range of applicability of this formulation and, in particular, to apply the FH4 potentials with great caution. A simple model of NN isotropic harmonic oscillators allows us to propose a means of estimating the cut-off temperature for the validity of the method, which is found to increase with the number of atoms adsorbed on the coronene molecule
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