1,720,958 research outputs found

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

    Daily performance of a sustained attention task during light phase desynchronizes circadian oscillators in nocturnal rats.

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    Previous studies demonstrated that daily performance of a sustained attention task (SAT) for water reward during the light phase causes nocturnal rats to entrain to a diurnal activity pattern (Gritton et al., 2009). In addition, level of performance during the light phase was significantly lowered when compared to dark phase performance. We hypothesized that the shift to a diurnal activity pattern observed in animals trained during the light phase was due to desynchronization of the SCN and peripheral oscillators. To test this hypothesis, SAT practice occurred either during the light phase at ZT4 [SAT4] or during the dark phase at ZT16 [SAT16]. A control group practiced a daily fixed interval 9 s [FI-9] schedule of reinforcement at ZT4. Light/dark cycle was 12:12 and food was provided ad libitum. A second control group was handled at randomly selected times but was neither water-deprived nor performed [NP]. Circadian behavioral activity was recorded to verify the SAT effect on circadian rhythm. As circadian clock operates in most tissues via transcriptional feedback that involve the products of circadian clock genes, we hypothesized that expression of the clock genes present in the gastrointestinal tract (Hoogerwerf et al., 2007) were altered in SAT4 animals. Preliminary data show that SAT4 animals have dampened Period2 (Per2) rhythms in the colon when compared to FI-9 and NP animals. Results from ongoing experiments indicate that Per2 expression in the SCN is not altered by SAT4 practice; however, in non-SCN areas in the brain Per2 expression is attenuated. To better understanding the relationship between the SCN and the peripheral oscillators, additional biopsy data was collected from the heart, lung, liver, kidney, and stomach at 4 time points (ZT2, ZT8, ZT14, and ZT20). As circadian misalignment is associated with diabetes, obesity and metabolic syndrome, food intake and stool output of SAT4, SAT16, FI-9 and NP animals were collected. SAT4 animals’ food intake was significantly higher compared to NP and their gastrointestinal motility was altered as well. Furthermore, preliminary corticosterone data suggests that day/night differences are attenuated in SAT4 animals as compared to SAT16 animals, and SAT trained animals have overall elevated corticosterone levels compared to NP animals. This research provides new insights in understanding cognitive work-induced shifts in circadian rhythms, the cause and role of circadian abnormalities in neuropsychiatric disorders, obesity and metabolic syndrome, and it eventually will inform the development of treatments of such disorders

    Timed, sustained, attention-demanding performance reorganizes or dampens multiple circadian rhythms.

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    Gritton et al (2009) reported that rats practicing daily a sustained attention task (SAT) at ZT4 exhibit inverted activity patterns, such that the majority of activity as measured by movement occurs during the light phase. This shift was not apparent in animals trained under several other control conditions, including an operantly similar simple reaction task that requires less cognitive vigilance performed at the same time of day. Here we report that the SAT performance also alters circadian running wheel activity at ZT4 in a similar manner. Furthermore, the SAT performance causes phase advances (diurnality) at ZT4, a smaller phase advance at ZT10 and small phase delays at ZT16. Core body temperatures (Tb) are consistent with running wheel records for training at ZT10 and ZT16. However, at ZT4 the Tb is no longer synchronized with running wheel records, and contain elements of both daily training and LD effects. Acetylcholine (ACh) release in the prefrontal cortex, as measured via microdialysis, anticipates and remains entrained for at least 3 days after the last training session at ZT4. Entrainment to the time of daily training also occurs at ZT16, but the anticipatory rise is absent. In contrast, an operant schedule of reinforcement devoid of explicit demands on cognitive processes (FI-9) did not shift activity at ZT4 also did not entrain ACh release. Animals practicing at ZT4 the SAT, but not the FI-9, exhibit dampened food intake, stool output, and corticosterone rhythms in addition to the noted changes in activity rhythms and ACh release. Finally, the per2 rhythm in the colon also had a dampened level of expression. These data suggest that attention-demanding tasks may act to attenuate SCN-control of peripheral oscillators

    Dispelling the Myths Behind First-author Citation Counts

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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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