172,656 research outputs found
Concentration in Knowledge Output: A case of Economics Journals
No full textThis paper assesses the degree of author concentration in seven economics journals, which were published in India during 1990-2002. To measure the degree of author concentration, Lotka's Law was used. Moreover, we also make an exploratory analysis of the geographic, economics subfield and institutional concentration in 704 economics journals. An important finding of this paper is that specialized journals in the sample report the highest degree of author concentration. This result is quite similar to the findings by Cox and Chung (1991). Furthermore, there are several instances showing that the journals lean towards certain norms; this may affect the flow of innovative ideas into economics. We conclude that a knowledge activity, involving the high degree of concentration and a biased publication process, may affect the flow of new ideas into the discipline.Concentration, Lotka's Law
Three-year experience of hypospadias surgery: Bracka′s method
No full textThis is the author′s experience of hypospadias reconstruction using Bracka′s technique (mainly) over a period of three years. A total of 98 procedures related to hypospadias were done in three years. The surgical technique is described. In the author′s hand, Bracka′s technique gives good result both functionally and in appearance. Its versatility enables its use in all types of hypospadias with consistently reproducible results with minimal complications. At the end of the second stage a circumcised penis with natural looking vertical slit neo-meatus at the apex of the glans is produced
Frequrncy response characterization
No full textThe fabricated device is characterized for its dynamic properties. The characterization setup is as follows. This piezoelectric buzzer is, in turn, attached to a rigid block using double-sided tape. Now, the piezo buzzer is actuated, and the response of the device is captured by the stroboscope software of Polytec vibrometer. Since a base excitation is given to the device, the relative displacement (displacement of the proof mass minus the displacement of the piezoelectric actuator) is represented in the Bode plot. The theoretical natural frequency is 289 Hz. And the experimentally observed resonant frequency is 268 Hz, as it can be seen that there is a phase change of 180 degree at 268 Hz.
The Q factor determined by the 3 dB bandwidth method is 335, so the slide film damping coefficient, c, is estimated to be 6.05e-10 Ns/m
Going 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
Mitomycin C in highly myopic eyes - Author reply
No full textOphthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
Dispelling 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
All Our Putures: Principles and resources for social work practice in a global era/ Ramanathan
No full textXVII, 277 hal: tab, ill: 23,5 c
Gene silencing and overexpression of porcine peptidoglycan recognition protein long isoforms
No full textPeptidoglycan recognition proteins (PGRPs) are a group of newly identified proteins with emerging functions in mammalian innate immunity. Here we report the identification and characterization of two long isoforms of porcine PGRP. Their complete cDNA sequences encode predicted peptides of 252 and 598 residues and are named pPGRP-L1 and pPGRP-L2, respectively. These porcine isoforms share identical PGRP domains at their C terminus, which are highly conserved with human and mouse orthologs. pPGRP-L1 is expressed constitutively in several tissues, including bone marrow, intestine, liver, spleen, kidney, and skin. pPGRP-L2 is highly expressed in the duodenum and liver, and expression in intestinal tissues is increased by Salmonella infection. In intestinal cells, expression of both pPGRP-L1 and pPGRP-L2 is increased by bacterial infection. Recombinant pPGRP-L1 and pPGRP-L2 have N-acetylmuramoyl-L-alanine amidase activity. Loss-of-function and gain-of-function experiments indicate that these two pPGRPs are involved in expression of the antimicrobial peptide beta-defensin-1. Silencing of pPGRP-L2 in intestinal cells challenged with Listeria monocytogenes results in downregulation of beta-defensin-1. Conversely, overexpression of pPGRP-L1 or pPGRP-L2 dramatically upregulates expression of beta-defensin-1. Collectively, these findings suggest that porcine PGRPs are involved in antimicrobial peptide expression.LR: 20061115; PUBM: Print; GENBANK/AF541955; GENBANK/AF541956; JID: 0246127; 0 (Carrier Proteins); 0 (DEFB1 protein, human); 0 (Protein Isoforms); 0 (beta-Defensins); 0 (peptidoglycan recognition protein); ppublishSource type: Electronic(1
All Our Putures: Principles and resources for social work practice in a global era/ Ramanathan
No full textXVII, 277 hal: tab, ill: 23,5 c
A new rational IPA and application to cruise tourism
No full textAt least two versions of IPA, namely the simple IPA and the asymmetric IPA, are available in tourism literature (Albayrak and Caber, 2015; Pritchard and Havitz, 2006). The simple IPA involves asking customers their perceptions relating to importance of various performance criteria and how the firm has performed in terms of these criteria. The simple IPA assumes a symmetric relationship between performance in terms of various criteria and customer satisfaction. The asymmetric IPA or AIPA (Albayrak and Caber, 2013; Caber et al., 2013) recognizes that these relationships could be asymmetric and uses the three-factor theory of customer satisfaction (Matzler and Sauerwein, 2002) to argue that criteria could be basic, excitement or performance criteria and uses regression analysis. While AIPA is an improvement over IPA, AIPA calculations take into account only the magnitude of regression coefficients but not their level of significance. Further, figure 3 of Albayrak and Caber (2015) uses performance in Xaxis but impact asymmetry, not importance, in Y-axis. It is not clear why impact asymmetry should be considered synonymous to importance. In this research note, we propose a variation of AIPA and call it Rational IPA (RIPA). RIPA involves the following steps. Step 1. Collect relevant data. Step 2. Run two sets of regressions with overall customer satisfaction as the dependent variable, and performance in terms of various service criteria as dependent variables. The first set of regressions is called low performance regressions where only ratings below median levels for each criterion are considered. In contrast, the second set of regressions is called high performance regressions. As highlighted in previous studies (Hartline et al., 2003; Ramanathan and Ramanathan, 2011; Silverman and Grover, 1995), the criteria are classified based on the results of the two sets of regressions. 1 a. A critical criterion remains significant in all regressions (except for low performance in terms of the criterion). b. A desirable criterion is significant both for high performance and low performance in terms of the criterion. c. A satisfier criterion is significant for high performance regression in terms of the criterion but not significant for low performance. d. A dissatisfier criterion is not significant for high performance regression but significant for low performance in terms of the criterion. e. All other criteria are neutral criteria. Step 3. Prepare IPA matrix with the importance of criteria on the X-axis and performance (mean ratings) in the Y-axis. Step 4. Conduct IPA based on the criterion classification (importance) and achievement (performance). We demonstrate RIPA in the following steps using publicly available online data on customer ratings of cruise operations
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