1,721,285 research outputs found
Letter from A.C. Smith to Oscar Monnig
No full textLetter from A.C. Smith, director of the Smithsonian Museum of Natural History, to Oscar Monnig about the Moab iron
Semialarium mexicanum (Miers) A.M.W. Mennega, a new name for Hemiangium excelsum sensu A.C. Smith, not Hippocratea excelsa
No full textN. Hallé’s renaming of the genus Hemiangium A.C. Smith, in Semialarium N. Hallé necessitated a name change for the Mexican and Central American species Hemiangium excelsum (H.B.K.) A.C. Smith. Semialarium mexicanum (Miers) A.M.W. Mennega, comb. nov., is proposed as the new name
Physiological quality of Amburana cearensis (Allemão) A.C. Smith seeds stored / <br> Qualidade fisiológica de sementes armazenadas de Amburana cearensis (Allemão) A.C. Smith
No full textO objetivo deste trabalho foi determinar as melhores condições e períodos de armazenamento para conservação da viabilidade e vigor das sementes de Amburana cearensis (Allemão) A.C. Smith. O experimento foi instalado no Laboratório de Análise de Sementes (CCA - UFPB), seguindo-se um delineamento inteiramente ao acaso, cujos tratamentos constituíram-se de sementes acondicionadas em três tipos de embalagens (saco de papel Kraft, saco de pano de algodão e embalagem de papel alumínio); armazenadas em dois ambientes: ambiente de laboratório ± 25°C e 74,5% UR e geladeira 6 ± 2°C e 38% ± 3 UR), durante 270 dias. As características avaliadas foram: teor de água, porcentagem e índice de velocidade de emergência, comprimento e massa seca de plântulas. Após 270 dias de armazenamento a emergência das plântulas de A. cearensis acondicionadas na embalagem de papel alumínio e armazenadas em laboratório foi de 68%. A emergência e o vigor das sementes de A. cearensis são conservados, com eficiência, em todos os ambientes e embalagens por 90 dias e no ambiente de laboratório na embalagem de alumínio por 180 diasThis work aimed to determine the best conditions and storage periods adapted to conservation of seed vigor for Amburana cearensis (Allemão) A.C. Smith. The experiment was conducted at the Laboratory of Analysis of Seeds (CCA/UFPB), using an entirely randomized design. The treatments consisted of A. cearensis seeds packaged in: paper Kraft bags, bags of cotton and foil aluminum, two storage conditions: room temperature and humidity conditions and refrigerator for 270 days. The evaluated characteristics were: moisture content, percentage of emergence and emergence speed index (ESI), seedling length, and seedling dry matter. After 270 days of storage the emergence of A. cearensis seedlings of conditioned in aluminum packing and stored at laboratory was of 68%. The emergency and the vigor of A. cearensis seeds are conserved, with efficiency, in all the storage conditions and packings for 90 days; and under environmental conditions in packing of aluminum for 180 days
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
Metodologia para teste de tetrazólio em sementes de Amburana cearensis (Allemão) A.C. Smith Methodology for tetrazolium test in Amburana cearensis (Allemão) A.C. Smith seeds
No full textObjetivou-se com este trabalho estudar a metodologia do teste de tetrazólio para sementes de Amburana cearensis (Allemão) A.C. Smith, determinando as melhores condições de pré-umedecimento, bem como temperatura, período de coloração e concentração da solução de tetrazólio. Avaliou-se a coloração das sementes intactas e escarificadas (lixadas), ambas com tegumento, diretamente na solução de tetrazólio nas concentrações de 0,025; 0,050; 0,075 e 1% a 35 e 40ºC, por 12 e 24h no escuro. Verificou-se o pré-umedecimento para retirar o tegumento utilizando-se sementes intactas e escarificadas, as quais foram imersas diretamente em água e submetidas a embebição em papel toalha e por 12, 24, 36 e 48 horas em temperaturas de 35 e 40ºC. Após a determinação do método para retirar o tegumento os embriões foram submetidas à coloração em solução de tetrazólio nas concentrações de 0,025; 0,050; 0,075 e 1%. Com os resultados obtidos verificou-se a necessidade da retirada total do tegumento para que ocorra a coloração e que a temperatura de 40ºC é prejudicial para a embebição no pré-umedecimento. O teste de tetrazólio nas sementes de A. cearensis deve ser realizado com o pré-umedecimento das sementes escarificadas (lixadas) e imersas diretamente em água por 24 horas, na temperatura de 35ºC, para posterior retirada total do tegumento. E para atingir a coloração ideal os embriões devem ser imersos em solução de tetrazólio a 0,05% por 3 horas, a 40ºC.This work aimed to evaluate the methodology of tetrazolium test in Amburana cearensis (Allemão) A.C. Smith seeds, establishing the best pre-moistening conditions, as well as temperature, coloration period and tetrazolium solution concentration. The coloration of intact and scarified (sanded) seeds, both with tegument, was directly evaluated in tetrazolium solution at the concentrations of 0.025; 0.050; 0.075; and 1%, at 35 and 40ºC, for 12 and 24 h in the dark. Pre-moistening to remove the tegument was evaluated by using intact and scarified seeds, which were directly immersed in water and subjected to imbibition in paper towel for 12, 24, 36, and 48 h at 35 and 40ºC. After establishing the method to remove the tegument, embryos were subjected to coloration in tetrazolium solution at the concentrations of 0.025; 0.050; 0.075; and 1%. Based on the obtained results, the complete tegument removal is needed for coloration; besides, the temperature of 40ºC is harmful for imbibition during pre-moistening. The tetrazolium test in A. cearensis seeds should be performed including pre-moistening through direct immersion of scarified (sanded) seeds in water for 24h at 35ºC for later complete tegument removal. To achieve the ideal coloration, embryos must be immersed in tetrazolium solution at 0.05% for 3h at 40ºC
Avaliação do potencial fisiológico de sementes de Amburana cearensis (Allemão) A.C. Smith
Full text linkA semente é insumo básico que deve atender aos requisitos de qualidade fisiológica para garantir o estabelecimento de cultivos com alta produtividade. O presente trabalho teve como objetivo avaliar a eficiência de métodos que permitam separar as sementes em níveis de vigor, sendo utilizados para isso, quatro lotes de sementes de Amburana cearensis (Allemão) A.C. Smith (cumaru). As variáveis analisadas foram: teor de água, o peso de 1.000 sementes, porcentagem de germinação, emergência em campo, índice de velocidade de germinação e de emergência, comprimento e massa seca de plântulas do laboratório e campo. O peso de mil sementes não permitiu a separação dos lotes de sementes de A. cearensis em níveis de vigor, enquanto os testes de campo (emergência de plântulas, primeira contagem, índice de velocidade de emergência, comprimento e a massa seca das plântulas) são eficientes na separação dos lotes de sementes de A. cearensis em níveis de vigor
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
- …
