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Embryo rescue and polyploidization of interspecific crosses between Torenia fournieri and T. benthamiana
No full text夏蓳(Torenia fournieri Linden)為倒地蜈蚣屬植物，是臺灣夏季重要花壇植物，現今市面上流通之夏蓳皆為國外品種，臺灣具有原生種源，應有潛力開發本土自有的品種。已知本屬植物存在種間雜交受精後障礙。本試驗以夏蓳與臺灣原生之毛葉蝴蝶草(T. benthamiana Hance)進行種間雜交，透過胚拯救成功獲得雜交後代、並調查後代之性狀，切片觀察雜交胚及胚乳之發育情形，探討溫度對雜交後代生長與開花之影響，並以秋水仙素誘導雜交後代多倍體化，以增加觀賞價值。
在日/夜溫25/20 oC環境下，以夏蓳‘Clown Rose’為種子親與毛葉蝴蝶草為花粉親，以雜交授粉後12、14、16或18天之胚珠培養於含3g•L-1之 Hyponex培養基上，以授粉後16和18天培養者有較高的發芽率，而授粉後12或14天進行培養者則發芽率不佳，顯示授粉後天數是影響胚拯救成功與否的關鍵。
在日/夜溫25/20 oC環境下，以夏蓳 ‘Clown Rose’為種子親與毛葉蝴蝶草為花粉親，於授粉後8和12天進行胚珠培養，在添加0%、3%、6%或12%蔗糖濃度之1/2MS培養基中，胚發芽率極低。若於授粉後16天進行培養，以0%、3%或6%蔗糖之1/2MS培養基較適合，胚可順利發芽並發育為小植株；12%蔗糖會抑制發芽。另以授粉後8、12和16天之子房進行切片觀察。夏蓳自交授粉胚與胚乳發育完整，授粉後8天胚乳已充滿胚囊。夏蓳與毛葉蝴蝶草雜交者之胚和胚乳細胞數少。夏蓳自交授粉後12天胚乳充實，胚發育已達魚雷期，而與毛葉蝴蝶草雜交者胚僅發育至球胚期。授粉後16天，夏蓳自交者已有成熟胚且珠被絨氈層明顯加厚，雜交者胚乳發育較慢，缺乏完整內皮層結構。
夏蓳‘Clown Rose’與毛葉蝴蝶草雜交之後代，株型性狀皆為半匍匐性，花瓣顏色介於紫色與紫羅蘭色之間，花冠筒中具條帶性狀且唇瓣近喉部有黃色斑點。
將夏蓳、毛葉蝴蝶草與雜交後代置於日/夜溫30/25 oC和15/13 oC之自然光照室，栽培兩個月。夏蓳栽培於15/13 oC者皆萎凋死亡，而雜交後代雖生長緩慢，但仍可維持開花，顯示雜交後代可耐低溫至13 oC。
為誘導夏蓳與毛葉蝴蝶草雜交後代多倍體化，以1.25、2.5和5 mM秋水仙素進行瓶內莖段處理24、48、72和96小時。結果顯示已1.25 mM秋水仙素處理有較高之培植體存活率及出瓶時株高。經選拔出之多倍體後代之花朵長寬、保衛細胞長度和花粉粒徑皆顯著高於二倍體，而氣孔密度顯著較二倍體為低。多倍體株型和花色與二倍體無顯著差異。有一個多倍體單株可自交結實，經播種後可順利發芽。將14個疑似多倍體化植株以流式細胞分析儀確認倍體數，僅有編號234單株為四倍體，其餘13株參試植株皆為具有二倍體與四倍體細胞的混倍體。Wishbone flower (Torenia fournieri Linden) is one of the important summer bedding plants in Taiwan. There are Taiwan-native Torenia species, which could be used for breeding to develop domestic cultivars. However, post-fertilization barriers were known to exist when interspecific crossing. The objectives of the study were to 1) develop suitable conditions of ovule culture for producing progenies from crossing T. fournieri ‘Clown Rose’ and T. benthamiana, 2)investigate the floral traits of the progenies, 3) to observe endosperm and embryo development of selfed and crossed progenies, 4) determine the cold tolerance in progenies from crossing T. fournieri and T. benthamiana, and 5) induce polyploidization of the hybrid progenies with colchicines treatments to improve ornamental characteristics.
The ovules were taken 12, 14, 16, and 18 days after pollination (DAP) from crossing T. fournieri ‘Clown Rose’ with T. benthamiana and were cultured on Hyponex medium. Germination percentage was higher (12%-31%) when ovules were taken at DAP 16 and 18, as compared with 0.4% at 12 and 14 DAP. Time after pollination is vital for the success of ovule culture of the crossed progenies.
The ovules were taken 8, 12, and 16 DAP from crossing T. fournieri ‘Clown Rose’ with T. benthamiana and were higher cultured on 1/2MS medium with 0%, 3%, 6% or 12% sucrose. Germination percentage was higher when ovules were taken at 16 DAP than there at 8 or 12 DAP. Culture medium with 0%, 3%, or 6% sucrose increased germination percentage, while 12% sucrose significantly reduced germination. Capsules of self-pollinated T. fournieri ‘Clown Rose’, and those cross-pollinated with T. benthamiana were collected and sectioned at 8, 12, and 16 DAP. More embryo and endosperm development were observed in self-pollination than cross-pollination. At 8 DAP, embryo sac was fully occupied by endosperm in self-pollinated T. fournieri ‘Clown Rose’, whereas cross-pollinated ones had fewer embryo and endosperm cells. At 12 DAP, endosperm cells were enriched, and the embryo was at torpedo stage in self-pollinated T. fournieri ‘Clown Rose’. The cross-pollinated embryo remained at globular stage at 12 DAP. At 16 DAP, mature-seedlike embryo sac with thick-walled endosperm and enlarged endothelial cells were observed in selfed ‘Clown Rose’, whereas the development of cross-pollinated endosperm was significantly slower, without complete endothelial cells.
The hybrid progenies from crossing T. fournieri ‘Clown Rose’ with T. benthamiana were semi-prostrate. Corolla color ranged between violet and purple-violet. All flowers had papillae petals with yellow dot and corolla tube with strip pattern.
Torenia fournieri ‘Clown Rose’, T. benthamiana, and their hybrids were placed in natural light rooms with day/night temperature 30/25 oC and 15/13 oC for two months. T. fournieri ‘Clown Rose’ plants died when grown of 15/13 oC for two months, while the hybrid progenies flowered although grew slowly.
To induce polyploidization of progenies from crossing T. fournieri ‘Clown Rose’ with T. benthamiana, the stem section of the hybrids were treated in vitro with 1.25, 2.5, or 5 mM colchicine for 24, 48, 72, or 96 hours. A low concentration (1.25 mM) of colchicine concentration increase survival rate and plant height of the explants. The colchicine-induced polyploidy progenies had bigger pollens and flowers, longer guard cells, and fewer stomata density than the diploid ones. A fertile polyploid hybrid was obtained, as the progeny produced seeds that could germination. The ploidy level of the colchicine-treated individuals were analysed by flow cytometry. These techniques confirmed that, of the 14 putative polyploids, only code no.234 was tetraploid, and thirteen were mixoploid
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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