1,720,963 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
Enrofloxacin and ciprofloxacin residues in broiler chicken feathers after enrofloxacin oral administration
Full text linkAntibiotics in animal feed are a public health concern. Drug residues could eventually be detected in animal food products intended for human consumption. Our aim was to study the residue depletion of enrofloxacin and its metabolite ciprofloxacin in broiler chicken feathers. A validated HPLC-fluorescence method was used to quantify both compounds in feather samples. Broiler chickens were treated through drinking water with 10 mg Kg-1 d of enrofloxacin for 5 consecutive days. Feather samples were taken from 10 random birds per day until 9 days. Extraction was performed by a liquid/liquid technique. Both fluoroquinolones concentrations were determined by liquid chromatography with fluorescence detection. High levels of enrofloxacin and ciprofloxacin were found in feathers after oral administration and these compounds were detected for 9 days. Feather meal is a potential source of drug residues that can pass through the food chain when contaminated meal is fed to food-producing animals. In the present study enrofloxacin and ciprofloxacin concentrations were 0.20 to 5.46 µg g-1 between 1 to 9 days after final treatment, which means that withdrawal time fit for edible tissues is not adequate to reduce antimicrobial residues in chicken feathers. Further studies to establish a withdrawal time may be useful to avoid that drug residues could result in adverse health consequences like increase in antibiotic resistance.Fil: Marchetti, Maria Laura. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacológicos y Toxicológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Buchamer, Andrea Veronica. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacológicos y Toxicológicos; ArgentinaFil: Buldain, Daniel Cornelio. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacológicos y Toxicológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Mestorino, Olga Nora. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacológicos y Toxicológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin
Tissue depletion profile of ivermectin in rabbits
Full text linkAvermectins are largely used in different animal species. Ivermectin, the most popular avermectin, is used against a wide spectrum of endo and ectoparasites. Some mange mites are particularly sensitive to ivermectin. Notoedres cati var. cuniculi, the agent of rabbit mange, is particularly sensitive to ivermectin. Pharmacokinetic and residual studies of ivermectin in rabbits, however, are scarce. The objective of the present paper was to study the tissue residue profile of ivermectin (IVM) after subcutaneous (s.c.) administration of a 1% w/w solution. Sixteen young healthy male rabbits received 200 μg/kg of a 1% w/w ivermectin formulation subcutaneously. Groups of four treated animals were sacrificed at 10, 20, 30 and 40 days after injection. Samples of liver, fat, kidney and muscle tissue were obtained. IVM concentrations were determined by liquid chromatography with fluorescence detection after automatic solid phase extraction with SPE C18 cartridges. Ivermectin was detected after subcutaneous administration until 40 days. Muscle samples showed the lowest IVM concentrations throughout the study. The highest IVM concentrations at all sampling times were measured in liver and fat tissues. Nevertheless, IVM concentrations in all the tissues analyzed were below the accepted maximum residue limits recommended by the European Union at 20 days posttreatment.Fil: Marchetti, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacologicos y Toxicologicos.; ArgentinaFil: Buldain, Daniel Cornelio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacologicos y Toxicologicos.; ArgentinaFil: Buchamer, Andrea Veronica. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacologicos y Toxicologicos.; ArgentinaFil: Zeinsteger, Pedro Adolfo. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacologicos y Toxicologicos.; ArgentinaFil: Mestorino, Olga Nora. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Laboratorio de Estudios Farmacologicos y Toxicologicos.; Argentin
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
Tissue depletion of doxycycline after its oral administration in food producing chicken for fattening
Full text linkDoxycycline (DOX), tetracycline of second generation, is mainly active against Gram–positive and Gram–negative bacteria, aerobic and anaerobic. Although there are few pharmacokinetic studies in chickens, it is frequently used for the colibacillosis treatment, salmonellosis, staphylococcal infections, avian mycoplasmosis and chlamydia. The objective of this study was to evaluate the withdrawal time (WT) of DOX formulation at 25 % in edible tissues, after its oral (PO) use in broilers. Forty healthy chicks (30–35 days of age) were used. DOX was administered with drinking water for 5 days at 10 mg kg–1 (N = 36); four untreated animals were reserved (control). Six animals per group were euthanized by cervical dislocation after desensitization by passage of an electric current through the head, after 24 hours until 9 d post treatment and control animals also. Muscle, liver, kidney and skin/fat samples were obtained. DOX was determined by HPLC with UV detection. DOX concentrations were determined in all tissues examined; generally falling below the MRL at 7 d after administration is terminated. It was estimated 6.58, 8.18, 8.69 and 6.96 d of WT for muscle, liver, kidney and skin/fat, respectively. After DOX administration at a rate of 10 mg kg–1 for 5 days in drinking water, a WT of 9 d is suggested in poultry destined for human consumption.Fil: Mestorino, Olga Nora. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Zeinsteger, Pedro Adolfo. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Buchamer, Andrea Veronica. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Buldain, Daniel Cornelio. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aliverti, Florencia. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Marchetti, Maria Laura. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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