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CHEN, GING-ZHONG
No full text本研究主要目的除探討記述稗草皺縮矮化病毒（ERSV）引起之病徵、寄主範圍、傳播
特性外，並就其與水稻皺縮矮化病毒（RRSV）生體外之性質、血清類緣關係、核酸、
蛋白質以及病毒形態等特性加以分析比較，期以闡明兩種病毒之異同。
稗草皺縮矮化病主要病徵為植株矮化，分檗增加，葉色濃綠，葉片皺縮不平且於葉綠
形成鋸齒狀缺刻，並於罹病莖、葉之葉脈形成葉脈腫大現象。以帶毒媒介昆蟲接種２
１種禾本科植物結果，計有水稻、小米、小麥、黑麥草、龍爪稷、白茅、野稗及玉米
等出現病徵。
稗草皺縮矮化病毒由擬白背飛蝨（Sogatella longifurcifera）以持續方式傳播。成
、若蟲均能自罹病植物獲毒，約經９∼１０日潛伏期即可傳病，不同蟲群平均傳病蟲
率２２．７％。帶毒蟲最短獲毒及接種吸食時間分別為２小時及３０分鐘。擬白背飛
蝨最適獲毒及傳病溫度為２５℃。罹病植物對媒介蟲之傳病能力有顯著的影響，當媒
介蟲取食發病後３０日（２３．３％）及６０日（２０％）之病株，其傳病蟲率較取
食發病後１０日（１４．９％）及１４０日（９．６％）之病株為高。當取食同一病
株之葉片（２３．７％）或莖部（１９．６％）時，傳病蟲率較取食根部者（５．５
％）高。本病毒不能經卵傳播，亦不能經由其他七種棲息於雜草或水稻之飛蝨、浮塵
子類傳播。利用機械傳播方法不能傳播本病毒。利用玻璃毛細管將罹病粗汁液注射於
稗草幼苗之葉脈，約有５％供試苗表現病徵。以注射方法將罹病株汁液注射於擬白背
飛蝨，約有３２∼５７％供試蟲能獲毒及傳病。讓媒介蟲經由拉張之parafilm及食罹
病汁液，約有７．４％供試蟲能帶毒及傳病。
ERSV及RRSV之生體外性質方面，兩種病毒之熱不活化溫度均在７０∼８０℃間，稀釋
終點均為１０∼１０，帶毒擬白背飛蝨之稀釋終點為１０∼１０。
在４℃時，ERSV及RRSV之耐保存日數分別為９及１０日以上。兩種病毒經由三次凍結
及融解均不減低其感染力。以不同緩衝液萃取ERSV，並將汁液注射媒介蟲後之傳病率
順序為０．１M 醋銨酸，︿０．１M 磷酸緩衝液，︿０．１M 檸檬酸緩衝液，︿０．
１M 硼酸液，︿０．１M Tris緩衝液。RRSV於pH6-8 間病毒均極安定。以四氯化碳或
DaiflonS3 處理ERSV病毒時感染力分別為３１∼４５％；當以氯仿或正丁醇＋氯仿（
１：１）處理粗汁液時，病毒感染力顯著降低。證明ERSV與Fijivirus 亞群之病毒並
無血清類緣關係；但ERSV與RRSV間則具有血清類緣關係。
以 ％Polyacrylamide凝膠泳動時，ERSV可分析到１０條（３．０v ／cm，３０－４
６小時）或 條基因段（２．５v ／cm，４０－５０小時）；而RRSV均為１０條。以
WTV dsRNA 為標誌來同時泳動時，估算ERSV及RRSV之核酸分子量分別為１７．８９×
１０（１０條基因條）及１８．１５×１０daltons。
ERSV及RRSV蛋白鞘之電泳分析兩種病毒分析到１０種鞘蛋白構造單位。RRSV罹病植物
組織經固定，陰染後可在電顯微鏡下觀察到直徑５５∼６０nm之病毒粒子，偶亦可觀
察到直徑約７６nm之大型粒子，具A 突起。純化樣品陰染後，部份粒子可觀察到B 突
起。無突起中核直徑約４０∼４５nm。罹病植物葉片超薄切片可觀察到大量病毒粒子
分佈於韌皮細胞內之viroplasm 或散生於細胞質中或分佈於葉肉細胞內之細胞質並排
邛圍繞於葉緣體之周圍。帶毒媒介昆蟲擬白背飛蝨之組織器官超薄切片後可觀察到直
徑５０∼７５nm之病毒粒子，偶亦可觀察到直徑４０∼４５nm之未成熟粒子。病毒粒
子分佈於帶毒蟲之腦、複眼、胃盲囊、馬氏管或脂肪體等組織器官內。
以RRSV罹病葉片做成陰染標本，於電子顯微鏡下觀時，可發現直徑５０∼６６nm之病
毒粒子。純化樣品陰染時，可觀察到直徑５０∼５５nm之無突起中核或病毒亞粒子，
偶亦可觀察到B 突起中核。
綜合本研究結果ERVS與RRSV之媒介昆蟲種類、寄主範圍、病毒粒子構造、病毒核酸基
因段及蛋白鞘構造單位之排列位置均不相同，故二者為兩種不同之病毒。RRSV之部份
性質如病毒粒子具雙層蛋白鞘與第二亞群之病毒相似；而部份性質如核酸基因段大小
、排列位置及血清關係則於第三亞群相近似，故ERSV之分類地位仍有待商榷
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
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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