1,720,981 research outputs found
A microencapsulated feed additive containing organic acids, thymol, and vanillin increases in vitro functional activity of peripheral blood leukocytes from broiler chicks
Full text linkDuring the first week after hatch, young chicks are vulnerable to pathogens as the immune system is not fully developed. The objectives of this study were to determine if supplementing the starter diet with a microencapsulated feed additive containing citric and sorbic acids, thymol, and vanillin affects in vitro functional activity of peripheral blood leukocytes (PBLs). Day-old chicks (n = 800) were assigned to either a control diet (0 g/metric ton [MT]) or a diet supplemented with 500 g/MT of the microencapsulated additive. At 4 D of age, peripheral blood was collected (100 birds per treatment), and heterophils and monocytes isolated (n = 4). Heterophils were assayed for the ability to undergo degranulation and production of an oxidative burst response while nitric oxide production was measured in monocytes. Select cytokine and chemokine mRNA expression levels were also determined. Statistical analysis was performed using Student t test comparing the supplemented diet to the control (P ≤ 0.05). Heterophils isolated from chicks fed the microencapsulated citric and sorbic acids, thymol, and vanillin had higher (P ≤ 0.05) levels of degranulation and oxidative burst responses than those isolated from chicks on the control diet. Heterophils from the supplemented chicks also had greater (P ≤ 0.05) expression of IL10, IL1β, and CXCL8 mRNA than those from control-fed chicks. Similarly, nitric oxide production was significantly (P ≤ 0.05) higher in monocytes isolated from birds fed the supplement. The cytokine and chemokine profile in monocytes from the supplement-fed chicks showed a significant (P ≤ 0.05) drop in IL10 mRNA expression while IL1β, IL4, and CXCL8 were unchanged. In conclusion, 4 D of supplementation with a microencapsulated blend made up of citric and sorbic acids, thymol, and vanillin enhanced the in vitro PBL functions of degranulation, oxidative burst, and nitric oxide production compared with the control diet. Collectively, the data suggest feeding broiler chicks a diet supplemented with a microencapsulated blend of citric and sorbic acids, thymol, and vanillin may prime key immune cells making them more functionally efficient and acts as an immune-modulator to boost the inefficient and undeveloped immune system of young chicks
Isolation and characterization of a new T-even bacteriophage, CEV1, and determination of its potential to reduce Escherichia coli O157:H7 levels in sheep
Full text linkBacteriophage CEV1 was isolated from sheep resistant to Escherichia coli O157:H7 colonization. In vitro, CEV1 efficiently infected E. coli O157:H7 grown both aerobically and anaerobically. In vivo, sheep receiving a single oral dose of CEV1 showed a 2-log-unit reduction in intestinal E. coli O157:H7 levels within 2 days compared to levels in the controls. Copyright © 2006, American Society for Microbiology. All Rights Reserved.Fil: Raya, Raul Ricardo. The Evergreen State College.; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Varey, Peter. The Evergreen State College.; Estados UnidosFil: Oot, Rebecca A.. The Evergreen State College.; Estados UnidosFil: Dyen, Michael R.. The Evergreen State College.; Estados UnidosFil: Callaway, Todd R.. USDA Agricultural Station; Estados UnidosFil: Edrington, Tom S.. USDA Agricultural Station; Estados UnidosFil: Kutter, Elizabeth M.. The Evergreen State College.; Estados UnidosFil: Brabban, Andrew D.. The Evergreen State College.; Estados Unido
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
Organic acid blend with pure botanical product treatment reduces escherichia coli and salmonella populations in pure culture and in in vitro mixed ruminal microorganism fermentations
No full textFoodborne pathogenic bacteria can live in the intestinal tract of food animals and can be transmitted to humans
via food or indirectly through animal or fecal contact. Organic acid blend products have been used as nonantibiotic
modifiers of the gastrointestinal fermentation of food animals to improve growth performance efficiency.
However, the impact of these organic acid products on the microbial population, including foodborne
pathogens, remains unknown. Therefore, this study was designed to examine the effects of a commercial organic
acid and botanical blend product (OABP) on populations of the foodborne pathogenic bacteria, Escherichia coli
O157:H7 and Salmonella Typhimurium. Pure cultures (2 · 10
6
colony-forming units [CFU]/mL) of each pathogen
were added to tubes that contained water-solubilized OABP added at concentrations of 0, 0.1, 0.5, 1, 2, 5, and
10% (vol/vol; n = 3). Water-solubilized OABP reduced ( p < 0.05) the growth rate and final populations of E. coli
O157:H7 and Salmonella Typhimurium in pure culture at concentrations > 2%. E. coli O157:H7 and Salmonella
Typhimurium were added (2 · 10
5
and 3 · 10
6
CFU/mL, respectively) to in vitro mixed ruminal microorganism
fermentations that contained water-solubilized OABP at concentrations of 0, 1, 2, 5, and 10% (vol/vol; n = 3) that
were incubated for 24 h. OABP addition reduced ( p < 0.05) final populations of E. coli O157:H7 and Salmonella
Typhimurium in the ruminal fluid at concentrations ‡ 5%. The acetate–to-propionate ratios from the in vitro
fermentations were reduced ( p < 0.05) by OABP treatment ‡ 5%. Treatments to reduce foodborne pathogens must
be economically feasible to implement, and results indicate that organic acid products, such as OABP, can
enhance animal growth efficiency and can be used to reduce populations of pathogenic bacteria
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
Microencapsulated Sorbic Acid and Pure Botanicals Affect Salmonella Typhimurium Shedding in Pigs: A Close-Up Look from Weaning to Slaughter in Controlled and Field Conditions
No full textThe aim of this study was to assess the efficacy of a combination of sorbic acid, thymol, and carvacrol in
reducing the prevalence and shedding level of Salmonella Typhimurium in pigs either in a controlled challenge
environment or in a production setting. In the first study, 24 weaned piglets were separated in 4 isolation units (6
piglets/isolation unit). Each unit received either a basal diet (no treatment) or a microencapsulated mixture of
sorbic acid, thymol, and carvacrol at 1, 2, or 5 g/kg of feed. After 21 d, pigs were orally challenged with 6 log 10
colony-forming units of Salmonella Typhimurium. Blood samples and feces from rectal ampullae were collected
every week. On d56 of the study, pigs were euthanized and necropsied to collect intestinal contents
(jejunum through colon) and ileocecal lymph nodes. Samples were analyzed for Salmonella Typhimurium and
serological analysis was also conducted. In the second study, an all-in-all-out multisite pig farm that was
positive for monophasic Salmonella Typhimurium was followed throughout a production cycle from weaning to
slaughter. Pigs received either a basal diet or the basal diet including 5 g/kg of the microencapsulated additive.
Environmental, fecal, and blood samples were collected monthly, and cecal contents and ileocecal lymph nodes
were collected at slaughter to isolate and enumerate Salmonella. The results indicate that the additive at 5 g/kg
tended to reduce Salmonella fecal prevalence in both a controlled challenge ( p = 0.07) and in production
conditions ( p = 0.03). Nevertheless, the additive did not reduce the number of pigs seropositive for Salmonella,
nor it reduced the Salmonella prevalence at slaughter. The data indicate that these additives are not effective
alone but must be used in conjunction with appropriate containment measures at lairage in order to prevent
reinfection in pigs and to reduce the number of pigs carrying Salmonella entering the food chain
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
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