5,464 research outputs found
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
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
Correspondence on 'Seasonal variation in blood pressure:evidence, consensus and recommendations for clinical practice. Consensus statement by the ESH Working Group on Blood Pressure Monitoring and Cardiovascular Variability'
Full text linkUltraviolet radiation suppresses obesity and symptoms of metabolic syndrome independently of vitamin d in mice fed a high-fat diet
Full text linkThe role of vitamin D in curtailing the development of obesity and comorbidities such as the metabolic syndrome (MetS) and type 2 diabetes has received much attention recently. However, clinical trials have failed to conclusively demonstrate the benefits of vitamin D supplementation. In most studies, serum 25-hydroxyvitamin D [25(OH)D] decreases with increasing BMI above normal weight. These low 25(OH)D levels may also be a proxy for reduced exposure to sunlight-derived ultraviolet radiation (UVR). Here we investigate whether UVR and/or vitamin D supplementation modifies the development of obesity and type 2 diabetes in a murine model of obesity. Long-term suberythemal and erythemal UVR significantly suppressed weight gain, glucose intolerance, insulin resistance, nonalcoholic fatty liver disease measures; and serum levels of fasting insulin, glucose, and cholesterol in C57BL/6 male mice fed a high-fat diet. However, many of the benefits of UVR were not reproduced by vitamin D supplementation. In further mechanistic studies, skin induction of the UVR-induced mediator nitric oxide (NO) reproduced many of the effects of UVR. These studies suggest that UVR (sunlight exposure) may be an effective means of suppressing the development of obesity and MetS, through mechanisms that are independent of vitamin D but dependent on other UVR-induced mediators such as NO.</p
Books piece on a reading by Richard Price, author of Samaritan, which will b
No full textBooks piece on a reading by Richard Price, author of Samaritan, which will be presented at Rines Auditorium, Portland Public Library, on March 5
Francis Lee Utley (interview)
No full textThis interview is included in the American Folklore Society Oral History Project held at the Archive of Folk Culture, American Folklife Center, Library of Congress, Washington, D.C. This item consists of oral history interviews with folklorist Francis Lee Utley conducted in 1973 by Patrick B. Mullen and Richard Reuss for the American Folklore Society Oral History Project. This collection consists of 2 sound tape reels : analog, 3 3/4 ips, 2 track, mono. ; 7 in. Originally recorded on July 19, 1973 by Patrick B. Mullen on a 7-inch reel, 3 3/4 ips, 2 track at an unidentified location; and on November 3, 1973 by Patrick B. Mullen and by Richard Reuss at the annual meeting of the American Folklore Society in Nashville, Tennessee on a Sony audiocassette. Sound recordings are first generation copies on two sound tape reels, 7 in. Biography/History note: Francis Lee Utley was born May 25, 1907 in Watertown, Wisconsin, and died March 8, 1974. He was a folklorist, medievalist, linguist, educator, and author who earned his M.A. in 1934 and Ph.D. in 1936 in literature at Harvard University. He taught at Ohio State University and the University of California at Berkeley, and was president of the American Folklore Society from 1951-1952
The phytochrome-deficient pcd1 mutant of pea is unable to convert heme to biliverdin IXα
No full textWe isolated a new pea mutant that was selected on the basis of pale color and elongated internodes in a screen under white light. The mutant was designated pcd1 for phytochrome chromophore deficient. Light-grown pcd1 plants have yellow-green foliage with a reduced chlorophyll (Chl) content and an abnormally high Chl a/Chl b ratio. Etiolated pcd1 seedlings are developmentally insensitive to far-red light, show a reduced response to red light, and have no spectrophotometrically detectable phytochrome. The phytochrome A apoprotein is present at the wild-type level in etiolated pcd1 seedlings but is not depleted by red light treatment. Crude phytochrome preparations from etiolated pcd1 tissue also lack spectral activity but can be assembled with phycocyanobilin, an analog of the endogenous phytochrome chromophore phytochromobilin, to yield a difference spectrum characteristic of an apophytochrome-phycocyanobilin adduct. These results indicate that the pcd1-conferred phenotype results from a deficiency in phytochrome chromophore synthesis. Furthermore, etioplast preparations from pcd1 seedlings can metabolize biliverdin (BV) IXα but not heme to phytochromobilin, indicating that pcd1 plants are severely impaired in their ability to convert heme to BV IXα. This provides clear evidence that the conversion of heme to BV IXα is an enzymatic process in higher plants and that it is required for synthesis of the phytochrome chromophore and hence for normal photomorphogenesis.</p
A New Framework for the Citation Indexing Paradigm
Full text linkA new citation indexing paradigm is proposed: the cascading citation indexing framework (c2IF, for short). It improves the way research publications are assessed for their impact in promoting science and technology. Given a collection of articles and their citation graph, citations are considered at the (article, author) level. Each one article is uniquely identified by means of the Digital Object Identifier (DOI, http://www.doi.org). To identify each one author uniquely, a Universal Author Identifier (UAI) scheme is established. In addition to the citations directly made to a given (article, author) pair, citation paths that target each one citing article are also considered. The granularity of the paradigm is further increased by introducing the concept of the chord, whereby a citation path of length one co-exists with paths of length two or higher, involving the same source- and target- articles. The c2IF output emerges in the form
of a medal standings table, analogous to the one that ranks teams at athletic events: when two (article, author) pairs receive the same number of (direct) citations, the one that is cited by more popular articles (i.e. articles that comprise targets to a larger number of paths in the citation graph), is assigned a higher rank value
Sub-erythemal ultraviolet radiation reduces metabolic dysfunction in already overweight mice
Full text linkExposure to sunlight may limit cardiometabolic risk. In our previous studies, regular exposure to sub-erythemal (non-burning) ultraviolet radiation (UVR) reduced signs of adiposity and cardiometabolic dysfunction in mice fed a high-fat diet. Some of the observed effects were dependent on skin release of nitric oxide after UVR exposure. Here, we examine the effects of sub-erythemal UVR on signs of adiposity and metabolic dysfunction in already overweight mice, comparing the effects of two sunlamps with distinct emitted light spectra. Mice were fed a high-fat diet from 8 weeks of age, with UVR administered twice a week from 14 weeks of age until they were killed at 20 weeks of age. Mice were irradiated with the same dose of UVB radiation (1 kJ/m(2)) from either FS40 (65% UVB, 35% UVA) or CLEO (4% UVB, 96% UVA) sunlamps, but substantially more UVA from the latter. FS40 UVR (but not CLEO UVR) significantly reduced mouse weights and weight gain, compared to mice fed a high-fat diet (only). These effects were dependent on nitric oxide. Conversely, CLEO UVR (but not FS40 UVR) significantly reduced circulating LDL cholesterol. Both light sources reduced fasting insulin levels, and the extent of hepatic steatosis; the latter was reversed by topical application of cPTIO, suggesting an important role for skin release of nitric oxide in preventing hepatic lipid accumulation. These results suggest that there may be a number of benefits achieved by regular exposure to safe (non-burning) levels of sunlight or UV-containing phototherapy, with effects potentially dependent on the predominance of the wavelengths of UVR administered.</p
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