1,720,972 research outputs found
Aflatoxin B1 and clinoptilolite in feed for laying hens: Effects on egg quality, mycotoxin residues in livers, and hepatic mixed-function oxygenase activities
No full textNinety-six laying hens were allocated to four groups administered different diets (group 0-0 received a complete diet, group 0-AF received a diet supplemented with 2.5 ppm of aflatoxin B1 [AFB1], group 2-0 received a diet supplemented with 2% clinoptilolite [CPL], and group 2-AF received a diet supplemented with 2% CPL and 2.5 ppm of AFB1) for 4 weeks to evaluate the effect of AFB1 and/or CPL on egg quality and the ability of CPL to interact with the oral administration of AFB1. The possible effects of AFB1 on cytochrome P450-dependent hepatic mixed-function oxygenase (MFO) activities were also evaluated. Mycotoxin reduced yolk weight, while CPL influenced albumen percentage relative to that of eggs laid by chickens in group 0-AF. Eggs laid by chickens in groups 0-AF and 2-AF had stronger shells and weighed less than the eggs of other groups. The eggs of treated groups were lighter in color than those of the control group (P < 0.01), and the tendency to yellowness in eggs was increased by CPL, probably through the affinity of red pigments for adsorbents and a consequent prevalence of yellow tonality. Color parameters might be connected with AFB1's interference with lipid metabolism and pigment deposition. The livers of hens in groups 0-AF and 2-AF showed very low mycotoxin concentrations that were significantly different (P < 0.01). The highest levels observed were those in the livers of the hens receiving the diet supplemented with the mycotoxin alone. AFB1 did not exert any significant effects on the hepatic MFO activities examined
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
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
Effetti del metodo biologico sulla produzione quanti-qualitativa delle uova e sul benessere delle galline ovaiole
No full textWithin of the project “Sicurezza ed aspetti tecnico-economici e giuridici delle produzioni biologiche”, the work of the research group of DIMORFIPA dealt with the study of organic egg production. In the present paper are shown the results of a trial carried out during the first year of the project concerning the influence of housing system (outdoor vs battery cages) and feeding (conventional vs. organic diets) on some egg qualitative characteristics. During a four month-period, four groups of 27 Warren Isa Brown (8.5-9-month-old) laying hens were studied: AT (in which hens were kept outdoor and fed a conventional diet); AB (in which hens were kept outdoor and fed an organic diet); GT (in which hens were kept into battery-cages and fed a conventional diet) and GB (in which hens were kept into battery-cages and fed an organic diet). The diets were formulated so as to supply the same amount of protein and energy. Freshly laid eggs were collected at the beginning of the trial and every three weeks up to the end of the trial to determine some physical and qualitative parameters. Feed intake and egg production of groups AT and GT were, on the whole, higher than those of group AB+GB. All the eggs were classified into the category L, with a weight comprised between 63.00 and 72.99 g (Regulation EC No. 2295/2003, modified by Regulation EC No. 1515/2004).
At the end of the trial, the heavier eggs were observed in groups fed the conventional diet, while the higher percentage of eggshell was detected in eggs of group AT+AB. The natural daylight and motor activity of outdoor animals were supposed to increase mineral metabolism leading to a better mineral deposition into eggshell. Haugh index and pH values were improved in eggs deriving from hens allocated in cages. Yolk from groups AT and AB was heavier and more intensively coloured, owing to the possibility to eat feeds containing xanthophylls, such as grass, herbs and insects. The comparison between the type of diets (conventional vs organic ) did not pointed out any significant difference.
Based on these results, we can conclude that some egg quality characteristics can be significantly influenced by the housing system and only at a slightly extent by the diet. During the following year 2004 and according to the above described experimental design, a second trial has been carried out. Besides the productive and qualitative analyses of eggs, some behavioural parameters of hens were collected. The housing system was confirmed as the main factor affecting birds’ behaviour: regardless of feeding type, free-range farming reduced some abnormal behaviour of hens such as the over-explorative behaviour at feeder and improved the quality of the plumage. These results might account for the attainment of a higher degree of welfare for free-ranged layers, which is worthy of note considering that organic hens must have access to outdoor areas
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
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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