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Studies of the habitat and ecological relationships of the microendemic species Nicotiana gandarela Augsten & Stehmann (Solanaceae) reveal the importance of conserving geodiversity in the Iron Quadrangle.
No full textMicroendemic and/or endangered species, with little knowledge about their ecological requirements, need urgent investment in research to support conservation guidelines. The subject of this study is the microendemic species Nicotiana gandarela Augsten & Stehmann, Solanaceae family, which occurs exclusively in the locality of André do Mato Dentro, Serra da Gandarela, Santa Bárbara, MG, Brazil. The general objective was to characterize the phenology, ecophysiological aspects, elementome, environmental requirements of the species, in order to identify the main environmental factors/filters involved in its microendemic character, as well as its current distribution of occurrences. The phenological studies covered the reproductive and vegetative phenophases, every two weeks for 17 months. At the same time, the microclimatic variables of air humidity and temperature were recorded using a datalogger in order to identify possible phenological associations with the microclimatic variables. For the ecophysiological studies, the light intensity and light spectrum were characterized using a spectrometer, with three measurements during the day, 8am, 12pm and 3pm. Gas exchange analysis was carried out using a portable infrared gas analyzer (IRGA), with a 6 cm² aperture camera coupled with an LED light source. The electron transport rate (ETR) in relation to light intensity was obtained from rapid light curves using a fluorometer. The specific leaf area (SFA) was calculated based on leaf area (LA) and leaf dry mass (DM), using the formula SFA = LA/MD, with leaf area obtained through photography and digital image processing. The photosynthesizing pigments were extracted in DMSO (Dimethylsulphoxide) stored in amber glasses for 48 hours in dark conditions and at room temperature (22 ± 2 ºC) and quantified in a spectrophotometer reader for the following wavelengths: 480, 649 and 665nm. The content of total chlorophylls (Ca+b), the ratio between chlorophyll a and b (Ca/b), and the ratio between chlorophylls and carotenoids (total chlorophyll/carotenoids) were also calculated. For comparative soil analyses, samples were obtained from the microhabitats of the known populations, as well as from similar environments in the Serra da Gandarela, with the presence of dolomite outcrops, during the search for new population records. With regard to the phenological profile, the species had a higher proportion of annual individuals, with reproductive phenology concentrated in the dry season, with a certain phenological lag between subpopulations and individuals evaluated. A potential association of most of the phenophases was identified with the air humidity variable, and the other variables were eliminated due to the occurrence of multicollinearity. The rarity of the species is linked to its evolutionary and restrictive adaptation to intensely shaded environments formed by carbonate (domolitic) rock outcrops, in which the soil has high ph, magnesium and silt values. The results of the soil analysis and other characteristics of the microhabitats studied, together with the evidence obtained for the elementome of N. gandarela, indicate the potential existence of a highly specialized floristic community (dolomitophytes) and singular in the complex of dolomitic outcrops and dolomitic marbles of the Gandarela formation distributed in the Iron Quadrangle.Espécies microendêmicas e/ou ameaçadas de extinção, com escassos conhecimentos acerca de suas exigências ecológicas, necessitam investimentos urgentes em pesquisas para subsidiar diretrizes de conservação. O objeto de estudo se trata da espécie microendêmica Nicotiana gandarela Augsten & Stehmann, família Solanaceae, com ocorrência exclusiva para a localidade de André do Mato Dentro, Serra da Gandarela, Santa Bárbara, MG, Brasil. Como objetivo geral pretendeu-se caracterizar a fenologia, aspectos ecofisiológicos, elementoma e requerimentos ambientais da espécie, de forma a identificar os principais fatores/filtros ambientais envolvidos em seu caráter microendêmico, assim como sua atual distribuição de populações. Os estudos fenológicos contemplaram as fenofases reprodutivas e vegetativas, com frequência quinzenal, durante 17 meses. Concomitantemente foi feito o registro das variáveis microclimáticas de umidade do ar e temperatura, por meio de datalogger, para identificar possíveis associações fenológicas com as variáveis microclimáticas. Para os estudos ecofisiológicos, foi realizada a caracterização da intensidade luminosa e o espectro luminoso utilizando um espectrômetro, com três medições durante o dia, 8hs, 12hs e 15hs. As análises de trocas gasosas foram realizadas com um analisador portátil de gases infravermelho (IRGA), com câmara acoplada de abertura de 6 cm2 com uma fonte de luz LED. A taxa de transporte de elétrons (ETR) em relação à intensidade luminosa foi obtida a partir de curvas rápidas de luz utilizando um fluorômetro. A área foliar específica (AFE) foi calculada com base na área foliar (AF) e massa seca foliar (MS), pela fórmula AFE = AF/MS, sendo área foliar obtida por meio de fotografia e processamento digital das imagens. Os pigmentos fotossintetizantes foram extraídos em DMSO (Dimetilsulfóxido) acondicionado em vidros âmbar armazenados por 48 horas em condições escuras e sob temperatura ambiente (22 ± 2 º C) e quantificados em um leitor espectrofotômetro para os comprimentos de onda: 480, 649 e 665nm. O teor de clorofilas totais (Ca+b), razão entre clorofila a e b (Ca/b), e razão entre clorofilas e carotenoides (clorofila total/carotenoides) também foram calculadas. Para análises comparativas de solo foram obtidas amostras nos microhábitats das populações conhecidas, assim como em ambientes similares na Serra da Gandarela, com presença de lapas de afloramentos dolomíticos, durante a busca por novos registros de populações. Com relação ao perfil fenológico, a espécie apresentou maior proporção de indivíduos anuais, com fenologia reprodutiva concentrada na estação seca, com certa defasagem fenológica entre subpopulações e indivíduos avaliados. Foi identificada associação potencial de grande parte das fenofases com a variável de umidade do ar, sendo as demais variáveis eliminadas, devido a ocorrência de multicolinearidade. A raridade da espécie está atrelada à sua adaptação evolutiva e restritiva aos ambientes intensamente sombreados e formados pelos afloramentos rochosos carbonáticos (domolíticos), nos quais o solo apresenta altos valores de ph, magnésio e silte. Os resultados das análises de solo e demais características dos microhabitats estudados, juntamente com as evidências obtidas para o elementoma de N. gandarela, indicam a existência potencial de uma comunidade florística altamente especializada (dolomitófitas) e singular no complexo de afloramentos dolomíticos e de mármores dolomíticos da formação Gandarela distribuída no Quadrilátero Ferrífero.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio
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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