1,720,966 research outputs found
DIETARY INTERVENTIONS TO IMPROVE HEALTHY STATUS IN PIG INTENSIVE FARM CONDITIONS: A MORPHO-FUNCTIONAL STUDY OF TARGET ORGANS.
Full text linkThe aim of my PhD thesis was to give a contribution in the field of improving pig welfare in different crucial phases of the rearing period. This on the basis that: i) keeping farm animals healthy is highly recommended for obtaining animal products that are safe for human consumers, and ii) pathologies and difficulties in food animal species growth result in severe economic losses in farming; really, a correct nutritional management may play a key role in animal production, above all when performed utilizing a multidisciplinary approach. We already know that the appropriate dietary composition and amount of nutrients are determinant for an optimal growth of animals. After the banning (2006) from EU countries of the use of chemotherapeutics as growing substances, the interest of scientific researchers for alternative nutritional strategies appears more and more increasing. Various nutritional approaches with different dietary integrations have been tested in the recent years for finding alternatives to the limited use of chemotherapeutics in animal rearing, as well as for enhancing the intrinsic quality of a food product of animal origin. In the last year most literature focus on the so called nutraceuticals. Here I present three assays aimed at evaluating the effects of different dietary supplementations in pigs in two different phases of the intensive farm industries: weaning, which is most often accompanied by acute stress, and growth-finishing period, which is characterized by a long term stress. In all these studies my approach was micro-anatomical, consistent with morpho-functional analyses of the pig alimentary tract. In addition with the description of important structural details, sometimes differently quantified (histometry) in treated animals in comparison with control ones, the used micro-anatomical approach let me to hypothesize in some instances mechanisms of action of the studied dietary interventions. Moreover I have worked to correlate the results obtained with the used micro-anatomical methods with those aimed at evaluating growth performance, thus respecting a multidisciplinary approach, which is useful when approaching the swine that is important both as a food animal species, and a largely used animal model for approaching biomedical themes important for human medicine.
In the first assay I studied the way to manage oxidative stress in the growth-finishing phase. The aim of the study was to investigate whether the use of verbascoside (VB), a polyphenolic plant compound, could modulate pig feeding oxidative and/or nitrosative stress in the gut. Eighteen male piglets were assigned to two groups, which were fed with either a control diet (CON) or a diet supplemented with 5 mg/kg of verbascoside (VB) for 166 days. At slaughter, duodenum and jejunum specimens were collected. Immunohistochemistry and Western blot analyses were performed on the samples to evaluate free radical adducts, including acrolein (ACR), 8-hydroxydeoxyguanosine (8-OHdg) and nitrotyrosine (NT). A KRL test was also used to assess the total blood antioxidant activity. Immunohistochemistry and Western blot showed that dietary treatment decreased the levels of nitrotyrosine in enteroendocrine cell populations (P<0.05). Characterization of the enteroendocrine cell typology was then performed, and serotonin immunoreactive cells were revealed to be directly involved in decreasing nitrosative stress status. This preliminary study demonstrates the important role of dietary VB in decreasing stress biomarkers in swine gut, thus highlighting a possible intervention aimed at building a large prospective for antioxidant dietary supplementation in food animal species.
In the second and third assays I studied how to manage the weaning period stressful condition focusing my attention on the intestine in the first work and on the liver in the second one. The effects of dietary supplementation of different copper sulphate forms (CuSO4) in post weaning piglets on growth performance, small intestinal and liver morphology and large intestine microbiota, as well as faecal and liver copper content were studied. At weaning 90 piglets were allotted to three dietary treatments for 18 d: control diet (with no copper sulphate) and two diets supplemented with 150 mg/kg of copper sulphate in protected and unprotected form. Unprotected copper sulphate showed a numerically higher feed:gain ratio. Moreover, duodenum villi length and crypts depth revealed to be higher in the treated animals (unprotected form). Furthermore, the two copper diets showed a decrease in Streptococci in the colon content, and an higher fecal copper content when compared to control animals (P<0.001). The obtained results revealed a modulation in the intestinal environment caused by addition of unprotected copper sulphate, as well as positive structural changes in the duodenum.
In the third and last work the aim of the study was to investigate whether the use of verbascoside in weaning pig feeding could modulate oxidative stress in the liver. Twenty four weaned female piglets were assigned to three experimental groups: the first group were fed a diet with 9% of sunflower oil (T1), the second one were fed with the same diet of the T1 but with an integration of antioxidant mix (T2), in particular with a 5 mg/kg of verbascoside (VB), and the third group was fed a control diet (C), where the oil was substituted by starch. The trial went on twenty nine days, and at the end the animals were slaughtered and the liver specimens were collected. Immunohistochemistry and Western blot analyses were performed on the samples to evaluate free radical adducts, including Heat Shock Protein (Hsp) 70, Hsp 90, lysozyme and desmin. These analyses showed an increase of the level of Hsp 70 in the liver treated with sunflower oil. A KRL test was also used to assess the total blood and plasma antioxidant activity. We evaluated also the impact of the use of antioxidant integrations with analyses on some plasma and liver enzymes related to oxidative stress: superoxide dismutase (SOD),catalase (CAT) and glutathione peroxidase (GPX). In the plasma compartment all enzymes were lower in the treated animals in comparison with control group. In the liver only SOD had significant results: T1 group presented a higher level of this enzyme related to other groups.
In conclusion, these three works support in my opinion the hypothesis that selected dietary integrations are possibly able to improve pig welfare in intensive farm, directing their actions, among other targets, upon the gut, and it is well known that a healthy gut may be responsible for a healthy individual. This in turn may be of a fundamental importance in the environment of the rearing farm that is so frequently rich of stressors, which may be with efficacy counteracted by nutraceuticals
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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