1,720,953 research outputs found
Assessment of Antibiotic Kamoran Against Acid Lactic Bacteria Contaminants in Ethanol Production From a Distillery Located in Valle del Cauca
No full textDigitalLas bacterias ácido lácticas (BAL) son consideradas contaminantes primarios en el proceso de fermentación de las destilerías, debido a su habilidad para tolerar altas temperaturas, bajos niveles de pH y su rápido crecimiento. Aunque su presencia en el proceso no supone una amenaza significativa para la calidad del producto final, sí afecta la eficiencia del proceso. Esto se debe a su capacidad para reducir el crecimiento, la viabilidad y la capacidad de fermentación de la levadura, por la generación de ácidos orgánicos. Para contrarrestar esta contaminación y controlar el crecimiento de las BAL en las destilerías, se emplean distintos tipos de antibióticos, como la penicilina, la virginiamicina, la estreptomicina, la monensina, entre otros. Es en este sentido, que el objetivó principal del trabajo fue aislar las BAL presentes en el proceso de fermentativo de la Destilería. Una vez se logró esto, se procedió a su identificación bioquímica y posterior se evaluaron solo las dos bacterias con mayor frecuencia de aparición en el proceso frente al antibiótico Kamoran, utilizando distintas dosificaciones y tiempo de exposición. Los resultados mostraron que, para la bacteria Lactobacillus paracasei, la dosificación más efectiva para controlar tanto la producción de ácido láctico como las unidades formadoras de colonias (UFC) fue a 7 ppm, durante un tiempo de 40 horas. Por otro lado, con la bacteria Lactobacillus pentosus, se observó que la mayor reducción de las UFC se alcanzó a las 16 horas; sin embargo, después de este periodo, las UFC aumentaron nuevamente. A pesar de ello, la dosificación de 7 ppm del antibiótico mostró un mejor control en la producción de ácido láctico. Por tanto, se sugiere realizar ensayos posteriores y considerar la adición nuevamente del antibiótico entre las horas 16 y 24 para esta bacteriaLactic acid bacteria (LAB) are considered primary contaminants in distillery fermentation processes due to their ability to tolerate high temperatures, low pH levels, and their rapid growth. Although their presence in the process does not pose a significant threat to the final product's quality, it does affect process efficiency. This is due to their capacity to reduce yeast growth, viability, and fermentation capability by generating organic acids. To counter this contamination and control LAB growth in distilleries, various types of antibiotics are used, such as penicillin, virginiamycin, streptomycin, monensin, among others. In this context, the main objective of the study was to isolate lactic acid bacteria (LAB) present in the distillery's fermentation process. Upon successful isolation, a biochemical identification was carried out, followed by an evaluation of the two most frequently occurring bacteria in the process against the antibiotic Kamoran. This assessment involved varied dosages and exposure times. The results revealed that, for Lactobacillus paracasei, the most effective dosage to control both the production of lactic acid and colony-forming units (CFU) was at 7 ppm over a 40-hour period. In contrast, with Lactobacillus pentosus, the greatest reduction in CFU occurred at 16 hours. However, after this time, CFU increased again. Nonetheless, the 7 ppm dosage of the antibiotic displayed better control over lactic acid production. Thus, further trials are recommended, and a re-administration of the antibiotic between the 16th and 24th hours for this bacteria should be considered.Introducción 20
Planteamiento del Problema 23
Pregunta de Investigación 26
Justificación 27
Hipótesis 29
Hipótesis Nula 29
Hipótesis Alterna 29
Marco Teórico 30
Biocombustibles 30
Biocombustibles en Colombia 31
Etanol 33
Características del Etanol Desnaturalizado 35
Etapas de la Producción de Etanol 36
Generalidades de las BAL 39
Características Fermentativas de las BAL 40
BAL Como Contaminantes en la Producción de Etanol 42
Ácido Láctico 44
Características Fisicoquímicas del Ácido Láctico 46
Producción del Ácido Láctico 46
Producción por Síntesis Química. 47
Producción por Síntesis Biológica. 48
Kamoran 50
Ingrediente Activo del Kamoran 51
Mecanismo de Acción del Kamoran 51
Estado del Arte 53
Objetivos 56
Objetivo General 56
Objetivos Específicos 56
Metodología 57
Diseño del Estudio 57
Etapas Experimentales del Proyecto 57
Etapa 1: Aislamiento de las Bacterias Ácido Lácticas 57
Recolección de la Muestra 57
Aislamiento de las Bacterias Ácido Lácticas 57
Conservación de las Bacterias Ácido Lácticas 57
Etapa 2: Caracterización Bioquímica de las Bacterias Ácido Lácticas 58
Preparación del Inóculo 58
Inoculación de las Galerías. 58
Etapa 3: Evaluación de las Bacterias Ácido Lácticas Frente al Kamoran 59
Preparación del pre Inóculo 59
Preparación del Inóculo 59
Evaluación de las Bacterias Aisladas Frente al Kamoran. 59
Resultados y Discusión 61
Resultado 1: Aislamiento de las Bacterias Ácido Lácticas Presentes en el Mosto con Mayor Frecuencia de Aparición 61
Resultado 2: Caracterización Bioquímica de las BAL Aisladas 64
Resultado 3: Evaluación de las BAL Identificadas Frente al Antibiótico Kamoran 66
Conclusiones 78
Recomendaciones 79
Referencias Bibliográficas 80
Apéndices 91PregradoMicrobiólogo Industria
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
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
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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