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Performance and variability of Cordia alliodora (Ruiz & Pav.) Oken provenances in Tapajos highlands, Belterra - Pará
No full textO presente trabalho trata de um ensaio de procedências de Cordia alliodora (Ruiz & Pav.) Oken, instalado no planalto de Tapajós, em Belterra, Estado do Pará, cujas sementes foram fornecidas pelo Commonwealth Forestry lnstitute - Universidade de Oxford. Foram estudadas 9 procedências provenientes de diferentes países, sendo 8 da América Central e uma oriunda de Fiji. O delineamento experimental utilizado foi o de blocos ao acaso com 5 repetições. A parcela foi constituída de 49 plantas. O espaçamento entre árvores foi de 3 x 3 metros. Aos 30 meses de idade, as características altura, diâmetro à altura do peito (DAP), forma do fuste (persistência e retidão), sobrevivência, ausência de seca de ponteiro e dominância apical das plantas foram avaliadas e analisadas no intuito de se determinar variações entre as procedências e possíveis correlações entre suas características. Para algumas características, estudou-se também variações intra-procedências. Foi efetuado o estudo do comportamento das procedências para o crescimento em altura em função da idade. Finalmente, fez-se comparações entre as características das procedências de Cordia alliodora com as de Cordia goeldiana, uma espécie natural da região amazônica. Para o crescimento em altura em função da idade, o estudo do comportamento das procedências revelou que a maior variação genética ocorreu a partir dos 18 meses de idade. As procedências que tiveram as maiores alturas na fase de viveiro não foram necessariamente as mesmas quando da avaliação aos 30 meses de idade e vice-versa. Os resultados das análises de variância, obtidos aos 30 meses de idade, demonstraram existir variações genéticas entre as procedências para todos os caracteres avaliados, com exceção de sobrevivência e ausência de seca de ponteiro. Da variação fenotípica, maior participação genética foi encontrado para altura, retidão do fuste e dominância apical e menor proporção para DAP e persistência do fuste. Os coeficientes de variação revelaram a existência de variação fenotípica intra-procedências para altura, DAP, persistência e retidão do fuste, sendo a maior variação detectada para retidão do fuste e a menor para persistência do fuste. O estudo das correlações fenotípicas entre as características mostrou que, as melhores procedências para as características de crescimento são também as mesmas que apresentaram melhor qualidade de fuste. A correlação positiva e significativa entre sobrevivência e ausência de seca de ponteiro demonstrou que a seca de ponteiro afetou a sobrevivência das procedências. Correlações negativas, mas não significativas, foram encontradas entre sobrevivência e as demais características. Para as condições em que se realizou o ensaio, as procedências 32/77 (Turrialba - Costa Rica), 20/77 (San Francisco - Honduras), 53/78 (San Carlos - Costa Rica) e 19/77 (Finca la Fortuna - Honduras) foram as que reuniram o maior número de características favoráveis, mostrando-se mais promissoras para continuidade no programa de melhoramento. A espécie de origem local (Cordia goeldiana) apresentou comportamento mais ou menos semelhante às melhores procedências de Cordia alliodora (exóticas), para algumas características estudadas.The present work deals with a provenance trial of Cordia alliodora (Ruiz & Pav.) Oken, established on the Tapajos highlands, in Belterra state of Para, using seeds collected by the Commonwealth Forestry Institute - University of Oxford. Nine provenances from different countries were studied; eight from Central America and one from Fiji. The experimental design used was of randommized blocks with 5 replications. The plot was composed by 49 trees planted on 3.0 x 3.0 meters spacing. At the age of 30 months, the height growth characteristics, dbh, stem form (straightness and axis persistence), survival, shoot dieback absence, were evaluated. After wards, these characteristics were analysed with the purpose of determining variations between provenances, as well as any possible correlations between its characteristics. The intra-provenance variations were studied for some characteristics. The study of the behavior of provenances regarding height growth in relation to the age of plants was achieved. Finally comparisons were made between the characteristics of provenances of Cordia alliodora and Cordia goeldiana, a natural species from the amazon region. The study of the behavior of provenances regarding height growth in relation to the age of plants, revealed that the greater genetic variation occurred after the age of 18 months, and the provenances that had the greatest height in the nursery phase were not necessarily the same by occasion of the 30 month evaluation and vice-versa. The results of the analysis of variance, obtained at the age of 30 months, showed the occurrence of genetic variations between provenances for all the evaluated characters, except for survival and shoot dieback absence. From phenotipic variation, greater genetic participation was found for height, stem straightness and apical dominance, and lesser genetic participation for dbh and stem persistence. The variation coefficients revealed the existence of intraprovenances phenotipic variation for height, dbh, stem straightness and axis-persistence, occurring greater variation for the stem straightness and lesser for the stem persistence. The study of phenotipic correlations between characteristics showed that the best provenances for the growth characteristics are also the same that presented better stem quality. The positive and significative correlation between survival and shoot dieback absence demonstrated that the shoot dieback affected the survival of provenances. Negative but not significative correlations were found between survival and other characteristics. The provenances 32/77 (Turrialba-Costa Rica), 20/77 (San Francisco-Honduras), 53/78 (San Carlos-Costa Rica), and 19/77 (Finca la Fortuna-Honduras), for the conditions on which the trial was achieved, presented the greatest number of favorable characteristics, and are thus the most promising for the continuity of the improvement program. For some studied characteristics the species of local origin (Cordia goeldiana) presented a behavior similar to the best provenances of Cordia alliodora (exotic)
Avaliação de rendimento e índice de conversão da madeira no processamento industrial de algumas espécies nativas da Amazônia
No full textA otimização ou melhoria contínua nos processos de transformação mecânica da madeira é uma necessidade nas indústrias e deve começar pelo setor de desdobro primário. Em geral, as técnicas que vêm sendo empregadas neste setor em muitas indústrias, nem sempre levam a resultados satisfatórios de rendimento, qualidade do corte e economia no consumo de energia para o processamento. A forma mais adequada de gerar alternativas para solucionar estes e outros problemas passa pelo conhecimento do rendimento produtivo das indústrias e do volume de resíduos existente, além dos possíveis usos que podem ser dados a este material. Sendo assim, neste trabalho determinou-se os índice de conversão da tora em madeira serrada, da tora em lâminas torneadas, da tora em lâminas faqueadas e do serrado bruto em madeira beneficiada ou acabada. O rendimento médio obtido para a conversão de tora em madeira serrada foi de 61,7%, para a conversão de tora em madeira torneada foi de 63,1%, para a conversão de tora em madeira faqueada foi de 48,0% e para a conversão de serrado bruto em produto acabado foi de 54,3% para piso e 68,1 % para deck. O rendimento da indústria na transformação de madeira serrada, torneada, faqueada e de produtos acabados, depende diretamente da qualidade e sanidade das toras, das espécies, da mão-de-obra especializada ou treinada, da regulagem e manutenção dos equipamentos e do grau tecnológico da indústria.The continuous improvement in the process of mechanical transformation of timber is a need in the industries and it must start by the primary saw sector. In general the techniques that are being used by this sector in several industries do not lead to sufficient results of yield, quality of cutting and economics in the use of energy for the timber processing. The best way to create alternatives to solve these problems goes by the knowledge of the yield of the industries, the existing volume of woody debris, and the use of that material. So, in this work the indices of conversion of log to lumber, log to sliced veneers, log to rotary cut veneers, and lumber to processed timber were calculated. The medium yield obtained to convert log to lumber was 61.7%, log to sliced veneers was 48.0%, lumber to final product was 54.3% for floor and 68.1 for deck. The yield of the industry in the lumber processing, rotary cut veneers, sliced veneers and final products depends on the quality and health of logs, species, specialized labour, calibration and maintenance of equipment and technologic dimension of the industry
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
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
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
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