1,720,986 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
Risk of fracture prevention in spina bifida patients: correlation between bone mineral density, vitamin D, and electrolyte values.
No full textThe aim of our study was to investigate the relationship between bone mineral density (BMD), vitamin D, and electrolyte blood values in patients with spina bifida, to find a possible therapeutic regimen and an intervention to reduce the risk of fractures in this population.
METHODS:
BMD values were measured in 49 patients (32 females, 17 males; aged 14.1 ± 3.86 years; range 5-20 years) using dual-energy X-ray absorptiometry (DEXA) and were analyzed based on sex, the level of spinal involvement, vitamin D, and electrolyte values, physical activity, body mass index (BMI), and ambulatory status [patients were divided into three subgroups: full-time wheelchair (FTWC), limited ambulator (LA), and full-time ambulator (FTA)]. These data were analyzed considering sex-, age-, and BMD-matched values and compared with those of normal population.
RESULTS:
BMD was significantly lower in these patients compared with that in the general healthy population (Z-score: -1.2 ± 1.8); in particular, females had Z-score values significantly lower that of the males (Z-score: -2.43 ± 2.02; P < 0.0004). In FTWC subgroup, Z-score was lower than that of the other two subgroups (P < 0.009). Vitamin D values were significantly lower compared with those in the general healthy population (vitamin D spina bifida group: 14.6 ± 8.7 mg/dL; normal subjects: 35 ± 9.8 mg/dL; P < 0.001). Subjects with spina bifida showed hypophosphatemia (<3 mg/dL) because of the lower levels of vitamin D (3.1 ± 0.9 mg/dL; P < 0.001).
CONCLUSIONS:
Spina bifida patients showed lower BMD, vitamin D, and electrolyte values than the healthy population; hence, they have an increase risk of developing pathological fractures. Vitamin D supplementation for a longer time period could reduce this risk
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
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
Contrast enhanced gray scale and color Doppler voiding urosonography versus voiding cystourethtography in the diagnosis and grading of vesicoureteral reflux
No full textPurpose. The purpose of this study was to compare contrast-enhanced gray-scale voiding urosonography (CE-VUS) and contrast-enhanced color Doppler voiding urosonography (CE-CDVUS) with voiding cystourethrography (VCUG) to verify whether the use of color Doppler imaging improves the diagnosis and grading of vesicoureteral reflux (VUR). Methods. In 74 patients, CE-VUS and CE-CDVUS were compared with VCUG, which was used as the gold standard. SHU 508 A (Levovist) was used as the echo-enhancing contrast agent. VUR was diagnosed if hyperechoic dots or color signals were visualized in the ureter on sonograms. VUR grading was based on morphologic and dynamic findings on CE-VUS and morphologic and color findings on CE-CDVUS. VCUG was performed conventionally, and grading by VCUG was in accordance with the international system of radiographic VUR grading. Patients who voided during 1 examination only (either CE-VUS and CE-CDVUS or VCUG) were excluded from the study. Agreement between the results..
The prevalence of small intestinal bacterial overgrowth and methane production in patients with myelomeningocele and constipation
No full textSTUDY DESIGN:
Prospective study.
OBJECTIVES:
The objective of this study was to assess the prevalence of small intestinal bacterial overgrowth (SIBO), methane (CH4) production and orocecal transit time (OCTT) in children affected by myelomeningocele.
SETTING:
This study was conducted at the Catholic University in Rome, Italy.
METHODS:
Eighteen (6M/12F; 16.4±7.6 years) children affected by myelomeningocele were enrolled. All subjects underwent H2/CH4 lactulose breath tests to assess SIBO and OCTT. All patients performed a visual analog scale to investigate abdominal pain, bloating and flatulence, and maintained a diary of the frequency and consistency of the stool during the previous 7 days. A nephro-urological clinical evaluation of the number of urinary tract infections (UTIs) and neurogenic bowel disease score were also performed.
RESULTS:
Thirty-nine percent (7/18) of the children showed SIBO and 61% (11/18) presented a delayed OCTT. Moreover 44.4% (8/18) produced high levels of CH4. Interestingly, all myelomeningocele children who produced CH4 showed a delayed OCTT and a higher incidence of UTI, with a lower frequency of evacuation, compared with those with a normal or accelerated OCTT.
CONCLUSION:
The association between CH4 and constipation suggests that CH4 has an active role in the development of constipation. One of the most interesting features of our study is to identify a correlation between myelomeningocele, CH4, delayed OCTT and UTI. The intestinal decontamination with locally acting drugs in these children may reduce the number of UTIs and improve intestinal motility
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