117,613 research outputs found
Supplemental Material - Evaluation of Medication Exposure on Exacerbation of Disease in Patients With Myasthenia Gravis
Supplemental Material for Evaluation of Medication Exposure on Exacerbation of Disease in Patients With Myasthenia Gravis by Nick Petrucelli, Megan E. Barra, and Jennifer L. Koehl in The Neurohospitalist</p
Going Beyond Counting First Authors in Author Co-citation Analysis
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
Intra-varietal analysis of Olea europaea L. cultivars using morphological, biochemical and molecular markers
Classification of olive germoplasm results very complex due to the cv genetic variability, to the lack of reference standards and genome characterisation, and, moreover, in the confusion of names attributed to the cultivars resulting in numerous synonyms and homonyms. An example is represented by the cv Moraiolo with about 90 synonymies and often with marked agro-morphological differences; on the contrary, other cultivars, as Leccino, seem to be more conserved, since the cv-populations show little morphological differences. The present work was carried out with the aim to identify the genetic similarity among 25 accessions of the Leccino cultivar collected in their origin zone (Pistoia province) and in the adjacent ones (Florence, Pisa, Leghorn and Grosseto). Biometric indexes of tree, leaf, fruit and stone were compared with the electrophoretic data obtained using RAPDs and total proteins extracted from seed teguments. Morphological and biochemicalmolecular data showed similar relationships into the cultivar
Molecular markers for cultivar characterisation in olea Olea europaea L.. Acta Hort. n. 586, vol I, 97-100, 2002
Square Dancing with the Stars to Enhance Dynamic Hirschman Linkages?
In this Presidential Address, the author takes the reader on a reconnaissance of his life and time as a regional scientist. He points out scenery he found scintillating along the way, hoping that some may pick up the banner and chew on a few of the ideas for a while. He suggests a revisit to Albert O. Hirschman’s notion of key sectors and more empirical analysis related to Marcus Berliant’s and Masahisa Fujita’s notion of knowledge creation and transfer.Presidential Address, San Antonio, Texas, March 29, 2014 (53rd Meetings of the Southern Regional Science Association
Appropriate Similarity Measures for Author Cocitation Analysis
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
Regional decreases of free D-aspartate levels in Alzheimer's disease
N-methyl-D-aspartate (NMDA) receptors have been shown to be involved in learning and memory processes. In Alzheimer's disease, there is a reduction of NMDA receptors. Since D-aspartate is an endogenous agonist for the NMDA receptor we hypothesized that if there are reduced levels of this amino acid in the AIzheimer's brain this could raise the reduction of NMDA receptor signal transduction system and contribute to the marked memory deficits seen in these patients. Therefore, using a chromatographic HPLC method, the regional distribution of free D-aspartate levels in post, mortem human brain samples from patients with Alzheimer's disease (AD) (n = 5) and age-matched controls (n = 5) were determined. We found that the levels of D-aspartate are significantly lower in Alzheimer's patients compared to controls (range: from -35 to -47%; P < 0.01). However, no differences were found in the cerebellum, a region spared from the neuropathological changes of AD. These data suggest that decreased levels of D-aspartate could contribute to a lower NMDA receptor function and consequently contribute to the memory deficits seen in AD
Letter from unknown writer to Jesse L. Boyce
Letter to Jesse L. Boyce from unknown author (possibly Jack) about the investigation into the powder magazine located in the Grand Canyon. Some personal news is included in the letter such as the writer's marriage to the daughter of C.A. Taylor, former Supervisor of Cochise County
Dispelling the Myths Behind First-author Citation Counts
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
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