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A new, less invasive, laparoscopic-laparotomic technique for the cryptorchidectomy in the dog.
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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
Fertility ontrol by GnRH analogues in dogs.
No full textGnRH plays a pivotal role in reproduction by stimulating the release of gonadotrophins. Chemical substitutions in the GnRH molecule lead to analogues possessing antagonist or agonist activity (Paramo RM et al. 1993 J. Reprod. Fertil. Suppl. 47, 387–397). The highly potent agonist analogue, Buserelin, with up to 20 times of potency, by increasing binding affinity, desensitizing competitive receptors, and resisting metabolic degradation, shuts down rather than stimulates reproductive function (Bertschinger HJ et al. 2001 J. Reprod. Fertil. Suppl. 57, 275–283). In man, Buserelin is employed in several gonadal hormone-dependent diseases and for prostatic cancers. We suppress gonadal function in male dogs using Buserelin. Eight intact male German sheep dogs 20 months old were divided into two groups; A, 4 subjects treated for pharmacological castration (Buserelin acetate, 0.3 mg/each, s.c., every 8 h for 30 days) (Suprefact-Aventis Pharma, Italy); B, 4 subjects treated with placebo (NaCl, 0.9%, s.c., every 8 h for 30 days). Plasma testosterone concentrations were measured twice a week by RIA using commercial kits (Coat-A-Count, Los Angeles, USA). Clinical examination of the male genital tract was conducted by ultrasound monitoring. Before and after the pharmacological treatment, semen was collected and evaluated for macroscopic and microscopic parameters. After treatment, testicular specimens were collected by orchiectomy, fixed in Bouin's solution, and embedded in paraffin wax. Thin sections were cut and stained with hematoxylin/eosin. The presence of germ cells (spermatogonia to spermatozoa, Sertoli and Leydig cells number) were analyzed. Randomly selected fields of transverse and longitudinal sections of seminiferous tubules were observed and analyzed using a computer assisted image analyzer (MONO system, Italy). The images acquired were segmented and binarized in order to obtain the masks of the tubular profiles; the mean values of the area, major and minor axes, mean diameter, and perimeter occupied by the testicular tubules were calculated automatically. Data were analyzed by ANOVA test. After Buserelin, all dogs (group A) showed a reduction in testicular and prostatic diameters compared to group B. Azoospermia was observed in group A. Histological examination revealed a statistically significant cell reduction of the germinal line (spermatogonia and spermatocytes, P < 0.05; spermatids and spermatozoa, P < 0.001). GnRH pharmacological treatment induced a cessation of normal spermatogenesis at the spermatocyte level while no statistical difference in morphometric parameters of seminiferous tubules were observed. The basic testosterone level (3.2 ± 1.3 ng/mL) rose to 12 ± 3.7 ng/mL (21° day) and than shut down to 0.5 ± 0.3 ng/mL (30° day), giving a long-term suppression. The present study demonstrates that Buserelin is an anti-fertility agent that gives suppression of reproductive function in male dogs. The method may have a clinical application. The utilization of a Buserelin depot will be a successive step
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
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