1,721,549 research outputs found
Water pair potential of near spectroscopic accuracy. II. Vibration-rotation-tunneling levels of the water dimer
Get PDFContains fulltext :
14117.pdf (Publisher’s version ) (Open Access
Recommended from our members
Safety and tolerability of the antioxidant OPC-14117 in HIV-associated cognitive impairment
Get PDFCognitive impairment is a common and disabling complication of advanced HIV infection. Antiretroviral agents are the only proven therapies currently used for the treatment of HIV dementia, but the response to these agents is frequently unsatisfactory, short-lived, or complicated by intolerable side effects. We hypothesized that OPC-14117, a lipophilic antioxidant that acts to scavenge superoxide anion radicals, might ameliorate the toxic interactions between HIV infected macrophages and neurons. We conducted a double-blind, placebo-controlled, randomized clinical trial to assess the safety and tolerability of OPC-14117 240 mg per day. All 30 patients enrolled(15 per group) had cognitive impairment based on performance on neuropsychological tests. The primary outcome was tolerability of the study drug as measured by the proportion of subjects able to complete the study on their assigned dosage of experimental medication. Overall OPC-14117 was as well tolerated as placebo. Five subjects withdrew because of adverse experiences (two placebo, three OPC-14117). The OPC-14117-treated group had better scores on a clinical global impression scale, compared with the placebo group. There were trends toward improvement in the cognitive test scores; however, these changes were not statistically significant. These results demonstrate that this antioxidant intervention is well tolerated in cognitively impaired patients with advanced HIV infection, and suggest that a larger efficacy trial to assess the impact of OPC-14117 on cognitive performance is warranted
Inhibition of stimulated human leukocyte hydrogen peroxide generation by a novel antioxidant, OPC-14117
No full textOxygen free radicals generated by leukocytes may contribute to tissue injury after central nervous system (CNS) focal ischemia or trauma. Inhibiting oxygen free radicals has improved outcome in experimental models of these conditions and antioxidant therapy appears promising. We evaluated the ability of a novel antioxidant, OPC-14117, to reduce hydrogen peroxide (H2O2) production by stimulated human polymorphonuclear (PMN) leukocytes and monocytes. Stimulated PMN and monocytes were incubated with several concentrations of OPC-14117 for 20 min and H2O2 production, nmol/1 x 10(6) cells/30 min, was measured. OPC-14117 significantly reduced PMN H2O2 production (P less than 0.001) and monocyte H2O2 production (P less than 0.05). A dose response relationship was observed for both leukocytes, as the 100 microM drug concentration was significantly (P less than 0.05) more effective than the 10 microM concentration. These results demonstrate that OPC-14117 inhibits H2O2 generation by stimulated human leukocytes and support further studies of its effects in disorders such as CNS focal ischemia and trauma, conditions where antioxidant therapy may be beneficial
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
- …
