1,721,448 research outputs found
The invertebrate phagocytic immunocyte: Clues to a common evolution of immune and neuroendocrine systems
No full textIn invertebrates, lower vertebrates and higher vertebrates, a common pool of highly conserved molecules appears to mediate phagocytosis, the stress response and inflammation. Here, Enzo Ottaviani and Claudio Franceschi propose an evolutionary hypothesis based on an integrated network of adaptive mechanisms that are critical for survival. The macrophage plays a pivotal role in this process
The immunology of exceptional individuals: the lesson of centenarians
No full textCentenarians are the best example of successful ageing, since they have escaped the major age-associated diseases, and most are in good mental and physical condition. Here, Claudio Franceschi and colleagues discuss how the study of their immune systems reveals that several immune parameters are well conserved, suggesting that a complex remodelling of most immune parameters occurs with age, rather than a unidirectional deterioration
Genetic Theories of Aging
No full textThe aging theories are a very high number, and also many scientists proposed different ways of dividing and categorizing them. As a major subset of these theories, the genetic theories of aging include three main concepts: (1) the genetics of aging can be interpreted in the light of the evolutionary theories; (2) the genetics of aging and longevity can be informative if ecological and anthropological views are considered; (3) the genetics components underpin all the theories of aging even if not specifically stated
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“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
Full text linkWe 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
Osteoporosis, inflammation and aging
No full textOsteoporosis is substantially an age-related condition characterized by low bone
mass and increased bone fragility, putting the patients at risk of fractures, which
are major causes of morbidity and mortality in older people. Although aging and
estrogen deficiency are probably the two most important risk factors, osteoporosis
can occur in any age of life. There are a large number of risk factors for the
development of senile osteoporosis. Osteoporosis is currently attributed to various
endocrine, metabolic, and mechanical factors. However, recent discoveries
suggest that these risk factors could exert their effects through immunologically
mediated modulation of bone remodeling. Emerging clinical and molecular
evidences suggest that inflammation exerts significant influence on bone turnover,
inducing osteoporosis. Currently, growing understanding of bone physiology
suggests that factors involved in inflammation are linked with those critical
for bone remodeling process. Numerous proinflammatory cytokines have been
implicated in the regulation of osteoblasts and osteoclasts, and a shift towards an
activated immune profile has been hypothesized as important risk factor. Chronic
inflammation and the immune system remodeling characteristic of aging may
be determinant pathogenetic factors. Inflamm-aging itself plays a role in bone
remodeling through proinflammatory cytokines, together with other more
recently discovered immunological mediators and transcription factors. Senile
osteoporosis is an example of the central role of immune-mediated inflammation
in determining bone resorption
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
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