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GLOMALES OF TAIWAN .3. A COMPARATIVE-STUDY OF SPORE ONTOGENY IN SCLEROCYSTIS (GLOMACEAE, GLOMALES)
No full textDuring the course of investigation on the Glomales of Taiwan, numerous sporocarps of Sclerocystis were isolated and identified as S. coremioides, S. clavispora, sinuosa, S. rubiformis, S. taiwanensis, and liquidambaris. After detailed comparison among these species by optical and electron microscopy, the similarity of spore ontogeny and spore arrangement in sporocarps was determined. Chlamydospores of S. coremioides with long, slender subtending hyphae also produced sporophores the same as those of other species of Sclerocystis and Glomus. The chlamydospores of S. coremioides are not always occluded by septa. The suggestion to define Sclerocystis as a monotypic genus is rejected. A modified generic concept and a hypothesis to explain sporocarpic evolution of Sclerocystis are proposed
GLOMALES OF TAIWAN .4. A MONOGRAPH OF SCLEROCYSTIS (GLOMACEAE)
No full textSix species of Sclerocystis (S. clavispora, S. coremioides, S. liquidambaris, S. rubiformis, S. sinuosa, and S. taiwanensis) from Taiwan are described and illustrated, and a key to species is provided. Spores of these species were assigned to one of three size-classes based on an area index calculated by multiplying length x width: 1000-3000 mu m(2), 6000-8000 mu m(2), and intermediate sized spores. Sclerocystis clavispora and S. liquidambaris formed large and small spores, sometimes in the same sporocarp. Sclerocystis rubiformis and S. taiwanensis mostly produced smaller spores; however, the spore size of S. sinuosa and S. coremioides were mainly intermediate between smaller and larger spore groups
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
Mechanisms of Phosphate-dissolving by Fungi
No full text磷是所有生物重要的營養成分之一，目前為止磷最常被植物吸收利用的化合物是以自由態無機磷酸鹽(例如HPO4-2、H2PO4-)為主。土壤溶磷真菌(菌根菌等)可分泌磷酸酵素(Phosphatase)，將含磷有機化合物(Phosphoesters、Nucleicacid等)及含磷無機化合物(Pyrophosphate metaphosphate等)加以解離，釋出自由態無機磷酸鹽。或者在生長過程中釋出具有嵌合基之代謝有機酸如糖膠酸(Glycollic acid)、琥珀酸(Succinic acid)等可與土壤中鈣、鐵等金屬離子嵌合成複合物，增加釋出自由態無機磷酸鹽，此外亦可降低土壤pH，使磷礦石、磷灰石等含磷化合物之溶解度增加。不同氮、碳源及鉀濃度也會影響溶磷真菌的溶磷能力•玉米粒和溶磷真菌一起施入土壤，可以顯著增進土壤有效磷濃度。一般而言土壤中溶磷真菌以Aspergillus、Penicillium為主。溶磷真菌比溶磷細菌較能使土壤中沉澱之磷酸鈣、磷礦石溶解而釋出自由態無機磷酸鹽，真菌溶磷能力可以達到細菌溶磷能力的十倍左右。溶磷真菌比溶磷細菌較能保持溶磷特性，有的溶磷細菌在實驗室中經繼代培養(Subculture)後，便失去溶解磷化合物的能力。
Phosphorus is an important element of living things. Usually, phosphorus is taken up by plants in free forms of inorganic phosphate, such as H2PO4, HPO42. Some soil-borne phosphate-dissolving fungi (including mycorrhizal fungi) can release phosphatase to dissolve organic and inorganic phospho-compounds. These fungi may also produce some metabolites such as glycollic acid, succinic acid, which can act as chelators binding calcium or irons in the soil, and then increase indirectly the concentration of available phosphate. Additionally, the organic acid may decrease the pH of the soil, and enhance the solubility of rock phosphate or apatite. The variety of nitrogen and carbon sources, and potassium concentration in culture medium may also influence the phosphate-dissolving ablility of fungi.
Corn grains and phosphate-dissolving fungi incorporated into soil at the depth of 0-5 cm, can increase the concentration of available phosphate at the depth of 0-10 cm. Normally, Aspergillus and Penicillium are the major genera of phosphate-dissolving fungi in soil. Phosphate-dissolving fungi show 10 times better phosphate-releasing effect on rock phosphate and calcium phosphate, if compared with phosphate-dissolving bacteria. Besides, fungi can maintain the phosphate-dissolving ability longer than bacteria
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
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