1,720,956 research outputs found
Natural river biofilms in the bioremediation of steroid hormones
Get PDFOrientador: Prof. Dr. Júlio César Rodrigues de AzevedoCoorientador: Prof. Dr. Charles Windson Isidoro HaminiukTese (doutorado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia de Recursos Hídricos e Ambiental . Defesa : Curitiba, 23/06/2025Inclui referênciasÁrea de concentração: Engenharia AmbientalResumo: Hormônios esteroides são compostos orgânicos, que podem ser naturais ou sintéticos, utilizados na medicina humana e veterinária. No entanto, eles também são considerados desreguladores endócrinos devido à sua atividade hormonal, o que é uma preocupação quando esses compostos aparecem nos ambientes naturais. Uma técnica para eliminar esses contaminantes em ambientes aquáticos é a biorremediação, que utiliza microrganismos para remover substâncias indesejadas. Em águas naturais, por exemplo, comunidades microbianas complexas formam biofilmes, os quais podem adsorver, bioacumular, biodegradar e transformar esses contaminantes presentes no ambiente. Esta pesquisa teve como objetivo avaliar se biofilmes naturais de rios tem capacidade de remoção dos hormônios esteroides Estrona (E1), 17ß-estradiol (E2), 17a-ethinylestradiol (EE2) e Progesterona (PRO) de ambientes aquáticos. A pesquisa envolveu amostras de biofilme obtidas do Rio Alb em Karlsruhe, Alemanha, e do Rio Barigui em Curitiba, Brasil. Os biofilmes foram mantidos, tanto em ambientes fluviais naturais quanto em microcosmos controlados de laboratório, para conduzir testes de remoção dos compostos alvo. Os resultados experimentais demonstraram a remoção completa de E1, E2 e EE2 sob condições específicas, apresentando como principais mecanismos envolvidos na remoção a biodegradação e/ou biotransformação. A análise microbiológica mostrou que Proteobacteria, Bacteroidota, Actinobacteria, Firmicutes e Deinococcota, representaram os principais filos responsáveis pelo processo, mas as duas regiões de estudo apresentaram gêneros dominantes diferentes. Os micropoluentes presentes no ambiente afetam a comunidade de biofilmes, o que leva à sensibilidade entre certas espécies, enquanto promove resiliência e possível adaptação entre outras. Portanto, esta tese revelou o potencial dos biofilmes fluviais para a remoção simultânea de hormônios esteroides, fornecendo assim um método capaz de ser usado em aplicações de tratamento de águas residuais. Além disso, o estudo fornece insights valiosos sobre os mecanismos de remoção de hormônios esteroides em água superficial de rios urbanosAbstract: Steroid hormones are organic compounds that can be either natural or synthetic, and are used in both human and veterinary medicine. However, they are also considered endocrine disruptors due to their hormonal activity, which is a concern when these compounds are released into the environment. One technique for eliminating these contaminants in aquatic environments is bioremediation, which uses microorganisms to remove unwanted substances. In natural waters, for example, complex microbial communities form biofilms, which can adsorb, bioaccumulate, biodegrade, and transform these contaminants present in the environment. This study aimed to evaluate the ability of natural river biofilms to remove the steroid hormones Estrone (E1), 17ß-estradiol (E2), 17a-ethinylestradiol (EE2), and Progesterone (PRO) from aquatic environments. The research involved biofilm samples obtained from the Alb River in Karlsruhe, Germany, and the Barigui River in Curitiba, Brazil. The biofilms were maintained both in natural river environments and controlled laboratory microcosms to conduct removal tests of target compounds. The experimental results demonstrated the complete removal of E1, E2, and EE2 under specific conditions, with biodegradation and/or biotransformation being the main mechanisms involved in the removal. The microbiological analysis showed that Proteobacteria, Bacteroidota, Actinobacteria, Firmicutes, and Deinococcota, represented the main phyla responsible for the process, but the two study regions showed different dominant genera. Micropollutants present in the environment affect the biofilm community, leading to sensitivity among certain species while promoting resilience and possible adaptation among others. Therefore, this thesis revealed the potential of river biofilms for the simultaneous removal of steroid hormones, thus providing a method capable of being used in wastewater treatment applications. Furthermore, the study provides valuable insights into the mechanisms of steroid hormone removal in the surface water of urban river
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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