1,720,967 research outputs found
Study witj philogenetic criteria of the neuroprotective potential of "Parmeliaceae" lichens : mechanism of action of their secondary metabolites
Get PDFTesis inédita de la Universidad Complutense de Madrid, Facultad de Farmacia, Departamento de Farmacología y Biología Vegetal II, leída el 17-03-2017La ruptura del equilibrio que existe en condiciones fisiológicas entre especies pro-oxidantes (entre las que destacan las especies reactivas de oxígeno – ERO) y los sistemas antioxidantes provoca una situación de estrés oxidativo (EO) celular, que conlleva daño oxidativo a todas las biomoléculas, incluyendo proteínas, lípidos de membrana y ácidos nucleicos. Cuando el daño es excesivo o irreparable, se produce la muerte celular, generalmente por mecanismos de apoptosis. El EO afecta a todas las células del organismo, pero en especial medida, a las células del cerebro, que es un órgano especialmente susceptible al EO por sus características anatómicas y funcionales. Así, una sólida evidencia científica apoya la implicación del EO, como causa y/o consecuencia, en la patogenia de diversas enfermedades neurodegenerativas, entre las que destacan la enfermedad de Alzheimer, la enfermedad de Parkinson o la esclerosis lateral amiotrófica. Debido al incremento de la esperanza de vida y al envejecimiento paulatino de la población mundial, cada vez es mayor el impacto social y el coste sanitario de estos trastornos neurodegenerativos crónicos (asociados a la edad) que, además, carecen de tratamientos eficaces para prevenir, atenuar o retrasar la aparición de los característicos síntomas cognitivos o motores...Excessive levels of pro-oxidant species (namely, reactive oxygen species - ROS) in comparison to antioxidant systems may lead to the disruption of physiological redox homeostasis; this situation is called oxidative stress (OS). It provokes oxidative damage in biomolecules, including proteins, membrane lipids and nucleic acids. When cell damage is irreparable, it eventually leads to cell death, which normally occurs through the mechanism of apoptosis. Oxidative stress affects all cell types in the organism, but brain is especially sensitive to its noxious effects due to the peculiar anatomic and functional characteristics of that tissue. Furthermore, there are consistent scientific evidences that support the involvement of OS as a causal and/or consequential factor in the physiopathology of several neurodegenerative diseases, such as Alzheimeŕs disease, Parkinsońs disease and amyotrophic lateral sclerosis. The increase in life expectancy and the subsequent gradual ageing of the world population explain the remarkable and growing impact on society and the sanitary costs of these chronic neurodegenerative disorders (that are closely associated to ageing). Besides, these diseases lack effective treatments that prevent, attenuate or delay the onset of the specific cognitive and motor symptoms...Depto. de Farmacología, Farmacognosia y BotánicaFac. de FarmaciaTRUEunpu
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Nephromopsis annae – a new combination in the Parmeliaceae with notes on related species
No full textA new combination, Nephromopsis annae (Oxner) A.Thell & Divakar is proposed and the basionym Cetrariasubalpina Imshaug is preferred over the combination in Nephromopsis
Nephromopsis annae – a new combination in the Parmeliaceae with notes on related species [Elektronisk resurs]
No full textA new combination, Nephromopsis annae (Oxner) A.Thell & Divakar is proposed and the basionym Cetraria subalpina Imshaug is preferred over the combination in Nephromopsis
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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