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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
Effetti della stimolazione cronica in vivo del processo di autofagia-proteolisi epatica.
No full textAnti-aging effects of anti-lipolytic drugs
No full textGenetic disruption of insulin and insulin-like signaling pathways may extend
lifespan. Hyperinsulinemia and insulin resistance may accelerate aging. The
hypothesis was tested that a once-a-week life-long inhibition of insulin
secretion by the administration of anti-lipolytic drugs might have anti-aging
effects. Groups of 3-month-old male Sprague-Dawley rats were (a) given standard
laboratory food ad libitum (AL); (b) fed AL 6 days and fasted 1 day every week
(FW); (c) fed AL every other day (EOD), (d) fed like FW and given Acipimox (50
mg/kg b.w.) on the day of fasting (FWA) by the gastric tube. The AL, FW and EOD
groups received saline intragastrically. Treatment with ACIPIMOX transiently
decreased plasma free fatty acids, glucose and insulin and increased valine
plasma levels, and had no long-term effect on food consumption and body weight.
By age 6, 12 and 24 months subgroups were taken and the age-related changes in
liver dolichol and autophagic proteolysis--which are correlated with
life-expectancy--were measured. Liver dolichol levels increased and autophagic
proteolysis decreased in mature and older AL rats; EOD and FWA fully counteracted
these changes; FW rats had significant but smaller beneficial effects. It is
concluded that life-long weekly-repeated transient inhibition of insulin
secretion by antilipolytic drugs may have an anti-aging effect, additive to the
anti-aging effect of a milder caloric restriction. Speculation is that
transiently lower plasma insulin levels might stimulate the anti-aging
cell-repair mechanism autophagy, which has longer lasting effects on cell
housekeeping
L’effetto protettivo della restrizione calorica sul mantenimento dell’integrità delle citomembrane dipende dalla durata del trattamento.
No full textEffetti dell'invecchiamento e di interventi di restrizione dietetica sui livelli di dolicolo nei tessuti di ratto.
No full textVariations 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
The age-related accumulation of dolichol in rat liver may be correlated negatively with expectation of life
No full textIn order to test the hypothesis that the ageing-related alteration in membrane
lipids might reflect the biological age of rodents, the levels of liver dolichol
were assayed by the HPLC procedure in male ad-libitum fed (AL) Sprague-Dawley
rats aged 2, 6, 12 and 24 months, and in 24-month-old rats on anti-aging
food-restrictions (FR) differing in duration and in their effects on longevity.
Results showed that the effects on liver dolichol of FR initiated at 2, 6 and 12
months of age, or initiated at 2 and interrupted at 18 months of age were
significantly different, and reflected the differences in the effects of FR on
expectation of life (the longer the expected residual lifespan the lower the
content in liver dolichol). The conclusion is that assay of the quantity of
dolichol in the liver tissue may be used as a marker of the biological age of the
animal and therefore as an important biomarker of ageing
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