1,721,024 research outputs found
Investigating the nature of selective impairments in patients with Alzheimer's disease : relating structure and function
No full textThree tasks of selective attention were administered to test inhibition, visuospatial selective attention, and Decision-making in subjects with Alzheimer's disease (AD). Compared to normal elderly controls (NECs), subjects were significantly slower on the visuospatial and inhibitory tasks. The inhibitory measure revealed the largest (proportional reaction time) group difference. There were no significant inter-task correlations, suggesting the potential to fractionate selective attention.To assess the relationship between inhibition and atrophy in the anterior cingulate cortex (ACC), a manual segmentation was performed on T1 weighted MRI scans in NECs and AD subjects. We calculated the cerebrospinal fluid (CSF):grey matter ratio to obtain a biomarker of atrophy. The CSF:grey matter ratio was significantly greater in AD subjects than NECs. There was a significant correlation between task performance and the CSF:grey matter ratio in ADs, but not in NECs, suggesting that a relationship exists between inhibitory processes and atrophy in the ACC in AD
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
Mild cognitive impairment and the neuroanatomical changes associated with progression to dementia of the Alzheimer's type
No full textUsing longitudinal MRI volumetry we examined the relationship between the degree of cerebral atrophy and cognitive function in Mild Cognitively Impaired (MCI) subjects during the progression to Dementia of the Alzheimer's type (DAT). We used these patterns of atrophy to examine the Dichotomous Groups and Accelerated Aging theories of progression to DAT. We acquired MRI scans on 20 subjects with Mild Cognitive Impairment (MCI), 3 subjects with DAT, and 19 normal elderly controls. Scanning was carried out at two times with an average of 73 months between scans. At follow-up, 10 of the MCI subjects had progressed to dementia (Progressors) while 10 had remained stable (Non-Progressors). We found that the Progressors had a significant increase in medial temporal atrophy between Time 1 and Time 2, while the Non-Progressors remained stable. This data supports the Dichotomous Groups theory. Cognitively we found that delayed verbal recall followed the same pattern of change as medial temporal atrophy, but that language ability did not follow the same pattern of change as lateral temporal atrophy
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
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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