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Physiological mechanism of light-induced seminal root waving in rice seedlings
No full text光照是調控植物生長發育的重要環境訊息因子之一，本研究發現於水稻(Oryza sativa L.)種子發芽過程中，光照刺激會誘導秈型稻之台中在來1號(Taichung Native 1; TCN1)水稻種子根產生波動形態，而稉型稻之台農67號(Tainung 67; TNG67)則無此現象發生。幼苗局部照光之實驗結果指出，誘導根波動之光訊息主要是由根部組織直接接收及感應。由根部之切片觀察，發現光照會造成根部的中柱細胞兩側細胞產生不對稱生長，進而導致波動形態之發生。進一步觀察不同光質及光強度對TCN1水稻種子根之影響，結果發現不同光強度之紅光及白光處理下均會誘導TCN1水稻種子根產生捲曲及波動形態。另一方面，高光度之藍光(90 μmol m-2s-1)不會誘導根波動之現象發生，然而較低光度之藍光(30 μmol m-2s-1)則會誘導種子根波動；故不同藍光的光強度造成根部形態有明顯的差異。利用Aspirin抑制水稻內生茉莉酸之生合成，會降低TCN1水稻種子根於紅光(90 μmol m-2s-1)、低藍光(30 μmol m-2s-1)及白光(90 μmol m-2s-1)誘導下所產生的捲曲及波動百分比；進一步利用real-time RT-PCR分析TCN1水稻種子根中茉莉酸生合成及訊息傳導基因之表現，發現allene oxide synthase (OsAOS)家族基因、12-oxophytodienoic acid reductase 1 (OsOPR1)及root specific rice PR10 (RSOsPR10)均會受到紅光及白光處理而誘導其表現。N-1-naphthylphthalamic acid (NPA)會抑制生長素(Auxin)流出載體蛋白的功能，以破壞水稻之生長素極向運移，結果指出NPA會抑制白光誘導TCN1水稻種子根產生的波動形態且會影響根部之向地性反應。綜合以上實驗結果，推測茉莉酸生合成及生長素極向運移反應均為光照誘導TCN1水稻種子根產生捲曲及波動形態所必須之條件。Light is an important environmental factor controlling plant growth and development. In this study, it was observed that continuous white light can induce the wavy growth pattern of seminal roots in germinating rice (Oryza sativa L. cv. Taichung Native 1; TCN1) seeds. However, the phenotype of light-induced wavy root was genetic diverse among rice cultivars; for example, the light-induced wavy root could be presented in seedlings of indica type rice (such as TCN1), but could not be presented in that of japonica type cultivars (such as Tainung 67; TNG67). According to the experiment with plants partially exposed to light, it was suggested that the light signal for inducing the wavy roots were directly sensed by root tissues. Analysis of longitudinal sections of wavy seminal roots indicated that light-induced root waving was caused by the asymmetric cell growth on both side of vascular cylinder cells in the root tips. In addition to white light, red light (90 μmol m-2s-1) could also induce root curling phenotype on seminal roots. However; the blue light with high intensity (90 μmol m-2s-1) presented no effect on inducing root waving/curling. On the other hand, other results in our laboratory showed that low intensity (30 μmol m-2s-1) of blue light could induce root waving. Using Aspirin to inhibit endogenous jasmonic acid (JA) biosynthesis in TCN1 seedlings conducted the light-induced curling/wavy root phenotypes were absent. Furthermore, light effects on expressions of the genes involved in JA biosynthesis, i.e., allene oxide synthase (OsAOS) gene family and 12-oxophytodienoic acid reductase (OsOPR1), and a root specific JA-responsive gene, root specific rice PR10 (RSOsPR10) were observed. The data showed that transcript levels of most JA biosynthesis-related and JA-responsive genes were increased in white- and red-light conditions. Moreover, N-1-naphthylphthalamic acid (NPA), an inhibitor of auxin efflux carriers, was used to interrupt auxin polar transport in roots, and then the morphology of light-induced wavy root was eliminated. Thus, the results suggested that JA biosynthesis and auxin polar transport were essential for light-induced seminal root waving in seedlings of indica type rice
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
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