104,850 research outputs found
Effects of GM1 ganglioside on developing and mature serotonin and noradrenaline neurons lesioned by selective neurotoxins
No full textThe effect of exogenous GM1 ganglioside on selective neurotoxin-induced lesions of serotonin (5-HT) and noradrenaline (NA) neurons in both the central and peripheral nervous systems has been investigated in developing and adult rats and mice by employing neuro- and histochemical techniques. 5,7-Dihydroxytryptamine (5,7-HT) was used to lesion 5-HT neurons, and 6-hydroxydopamine (6-OH-DA) was used to lesion NA neurons. In most lesion models investigated the neurotoxin causes primarily an axonal nerve terminal damage without notably affecting the perikarya. There was no evidence indicating that GM1 interferes with the primary and direct neurodegenerative actions of 5,7-HT or 6-OH-DA on 5-HT and NA nerve terminals, respectively. In all lesion models GM1 had in the chronic stage a counteracting effect on the neurotoxin-induced nerve terminal lesion or enhanced regrowth. The present results are compatible with the view that GM1 has a regrowth-stimulating effect and/or protective actions against secondary retrograde degeneration following the initial nerve terminal lesion induced by the neurotoxin
GM1 GANGLIOSIDE PROMOTES RECOVERY OF CENTRAL AND PERIPHERAL NORADRENALINE NEURONS AFTER A SELECTIVE NEUROTOXIN INDUCED LESION
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
No mutations in the BACH1 gene in BRCA1 and BRCA2 negative breast-cancer families linked to 17q22
No full textDispelling the Myths Behind First-author Citation Counts
No full textWe 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
The construction of Karen Karnak: The multi-author-function
No full textThis thesis is situated within the comparatively recent developments of Web 2.0 and the emergence of interactive WikiMedia, and explores the mode of authorship within a Read/Write culture compared to that of a Read/Only tradition. The hypothesis of this study is that the role of the audience has become merged with the author, and as such, represents new functions and attributes, distinct from a more conventional concept of authorship, in which the roles of audience and author are more separate. Read/Write and participatory culture, as defined by this study, is focused on collaboration, and includes the influences of D.I.Y. culture, Open-Source practices and the production of text by multiple authors. Multi-authorship presents a re-thinking of several concepts which support the notion of the individual author, since the focus of multi-authorship is not on attribution and ownership of a finished text, but on the continued malleability of a text. Modes of multi-authorship, demonstrated in the use of the pseudonyms Alan Smithee and Karen Eliot, represent declarative authors whose names signify multiple origins, whilst concurrently indicating a distinct body of work. The function of these names form an important context to this study, since primary research involves the construction of an experimental mode of multi-authorship utilising WikiMedia technology and the interaction of thirty nine participants, who are invited to create a body of work under the collective pseudonym Karen Karnak. The data generated by this experiment is analysed using aspects of Michel Foucault's author-function to identify and determine power structures inherent in the WikiMedia context. The interplay of power structures, including concepts such as identity, ownership and the body of work, affect the resulting mode of authorship and contribute to the construction of Karen Karnak, suggesting further areas of research into the emerging multi-author
Contribution of Information and Communication Technology (ICT) in Country’S H-Index
No full textThe aim of this study is to examine the effect of Information and Communication Technology (ICT) development on country’s scientific ranking as measured by H-index. Moreover, this study applies ICT development sub-indices including ICT Use, ICT Access and ICT skill to find the distinct effect of these sub-indices on country’s H-index. To this purpose, required data for the panel of 14 Middle East countries over the period 1995 to 2009 is collected. Findings of the current study show that ICT development increases the H-index of the sample countries. The results also indicate that ICT Use and ICT Skill sub-indices positively contribute to higher H-index but the effect of ICT access on country’s H-index is not clear
Absence of circulating adrenal autoantibodies in adult-onset X-linked adrenoleukodystrophy.
No full textX-linked adrenoleukodystrophy (ALD) is a frequent cause of adrenal insufficiency in young-adult patients with Addison's disease. As the contribution of an autoimmune process in the destruction of steroid cells in ALD is unclear, the aim of the present study was to evaluate the occurrence of adrenal-, thyroid- and islet-specific and non organ-specific autoantibodies in adult ALD patients. In all 5 patients, Addison's disease was the first manifestation of ALD. None of the ALD patients were positive for adrenal cortex autoantibodies in an indirect immunofluorescence assay, or for 21-hydroxylase autoantibodies in a radiobinding assay with recombinant human antigen. Similarly, we found neither non-organ specific autoantibodies (such as anti-nuclear, anti-ribosomal, anti-mitochondria, anti-smooth-muscle, anti-liver/kidney microsomal or anti-reticulin autoantibodies), nor islet-cell antibodies or glutamic acid decarboxylase (GAD65 or GAD67) autoantibodies, nor thyroglobulin autoantibodies in the sera of the 5 ALD patients. Two out of five patients were positive for thyroid microsomal autoantibodies. One of the two latter thyroid antibody-positive patients had clinical symptoms of hypothyroidism, and the other presented high levels of circulating TSH but no clinical signs or symptoms of hypothyroidism. Our study demonstrates that adult ALD is not immediately associated with the presence of adrenal autoantibodies and suggests that adrenal insufficiency is not mediated by an autoimmune process in adult ALD patient
Fully Turbulent Mean Velocity Profile for Purely Viscous non-Newtonian Fluids
No full textThe characteristic near wall behavior of turbulent flow of purely-viscous non-Newtonian fluids is discussed for both power-law (P.-L.) and Herschel-Bulkley (H.-B.) rheological models. A proper scaling is presented for H.-B. fluids to establish an analogy with power-law fluids with same flow index. To provide reference data for turbulent flow of non-Newtonian fluids, DNS simulations of power-law fluids are conducted in a rectangular channel for a large range of power-law indices ( = 0.5, 0.69, 0.75, 0.9, 1, 1.2). The DNS data show that the mean velocity profile in the viscous and logarithmic layers follow expressions of the form and respectively, where shows a logarithmic dependency on the flow index.Comparison with some experimental data shows the above formulation to be valid for Reynolds numbers (based on shear velocity) as high as 1000
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