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The recognition region in SulA by ClpYQ protease from Escherichia coli
No full text大腸桿菌中ClpYQ蛋白酶為一種ATP依賴蛋白酶，由具有ATPase及unfoldase活性的ClpY，與具有peptidase活性的ClpQ所構成的雙單元體。這類蛋白酶在細胞中，可降解構形錯誤或是具危害性的蛋白質，以維持細胞正常生理作用，避免細胞受到危害。在ClpYQ蛋白酶中，ClpY會負責辨識基質，並水解ATP作為能量來源，將基質結構打開並傳送至ClpQ的活性區，以進行降解作用。然而，關於ClpYQ蛋白酶是如何選擇辨識基質，及後續降解作用的詳細機制，目前仍不清楚。SulA是一個細胞分裂的抑制物，當細胞暴露在逆境下時會產生SOS反應，誘導大量SulA蛋白表現，以避免受損的DNA傳到子代細胞。目前已知可分解SulA的蛋白酶為Lon及ClpYQ，其中又以Lon為主要負責分解的蛋白酶。之前有研究指出，Lon可以藉由辨認SulA之C-端末8個胺基酸，與之結合並將其降解，但是ClpYQ卻不能。對於ATP依賴蛋白酶來說，為避免不必要的降解，如何選擇辨認需要降解的基質是非常重要的。本實驗中，為確認ClpYQ蛋白酶辨認SulA蛋白的區域，建構SulA之C-端不同大小片段缺失的突變蛋白，以酵母菌雙雜交系統測試，各個SulA突變蛋白與ClpY之間交互作用的情形，發現ClpY辨識的區域可能位於C-端的高疏水性片段，C-端第20 - 30個胺基酸。於此區域內再建構點突變蛋白，分析不同性質的胺基酸對於ClpY交互作用的影響，結果顯示當點突變取代為親水性胺基酸時，會降低SulA蛋白與ClpY之間的交互作用。之後測試各個SulA突變蛋白的活性表現，及被ClpYQ蛋白酶降解之情形，結果顯示SulA之C-端第20 - 45個胺基酸的區域，對於其抑制細胞分裂的活性表現是重要的，且對於ClpYQ蛋白酶的降解作用也會造成影響，因此ClpYQ蛋白酶應可藉由SulA蛋白之活性表現與否，來辨別其是否需要降解。ClpYQ is an ATP-dependent protease from Escherichia coli and a two component complex composed of ClpY, which is an ATPase and unfoldase, and ClpQ peptidase. Degradation of denatured or damaged proteins by this proteases helps protect the normal cell growth from the harmful effects of these proteins. The ClpY is thought to recognize protein substrates, denature them, and translocate the unfolded polypeptide into the catalytic cavity of the ClpQ for degradation. However, little information is available on the recognition of substrates for ClpYQ and on the mechanism by which they were selected, unfolded, and translocated by ClpY to the interior of the ClpQ. SulA, induced in the SOS response, is a cell division inhibitor and prevents the distribution of damaged DNA into daughter cells during DNA repair processes. SulA can be degraded by ATP-dependent proteases such as Lon and ClpYQ, and the degradation in vivo seems to be predominantly by Lon, while ClpYQ appears to act as a backup for Lon. It was reported previously that the region of C-terminal eight amino acid residues of SulA was essential for interaction with Lon but not with ClpYQ. To avoid unnecessary degradation of cellular proteins, substrate selection by ATP-dependent proteases is tightly regulated; therefore, it is interesting to investigate the recognition region of SulA by ClpYQ. In this study, the deletion mutants of SulA with regard to C-terminus were constructed and the interaction with ClpY was analyzed in yeast two-hybrid system. The results showed that ClpY recognized the hydrophobic region of SulA, C20 - 30 aa, and the recognition was also likely to rely on hydrophobic interaction following the observation that the binding activity decreased if the substituted residue was polar. The C-terminal region of SulA, C20 - 45 aa, seemed to be important for its activity with an inhibition of cell division, and the region is necessary for the degradation by ClpYQ. Therefore, ClpYQ protease would be able to distinguish whether SulA is to be degraded by the activity of inhibition.目錄試委員會審定書 i謝 ii要 iiibstract iv錄 vi目錄 viii目錄 ix圖目錄 x、前言 1、ATP依賴蛋白酶 1、ClpYQ蛋白酶 2、ClpYQ複合體結構 4、ClpYQ蛋白酶之基質 5、細胞分裂抑制物SulA 7、蛋白酶對基質SulA辨認之相關研究 9、研究動機與目的 12、材料與方法 13、實驗材料 13一) 菌株與質體 13二) 藥品與試劑 14三) 器材設備 15四) 分析軟體 15、實驗方法 16一) 一般實驗方法 16二) 菌體的建構 20三) 突變基因建構 25四) 酵母菌雙雜交系統分析 28五) 大腸桿菌選殖基因表現系統 33六) 西方墨點分析 (Western Blotting) 35、實驗結果 41、確認SulA蛋白被ClpY辨識之區域 41一) 建構SulA蛋白C-端不同大小片段缺失之突變 41二) 以酵母菌雙雜交系統測試各個SulA突變蛋白與ClpY之交互作用 41、SulA蛋白被辨識區域之特性 43一) SulA蛋白C-端序列特性分析 43二) 於SulA蛋白被辨識區域中建構不同胺基酸性質之點突變 43三) 利用酵母菌雙雜交系統測試SulA點突變蛋白與ClpY之交互作用 44、不同蛋白酶對於SulA蛋白辨識區域之差異 45一) Lon蛋白酶與SulA缺失突變蛋白間之交互作用 45二) ClpY I domain上兩個loop對於SulA蛋白辨識之影響 46、SulA突變蛋白之活性表現及受ClpYQ蛋白酶降解之現象 47一) C-端末20個胺基酸缺失之SulA突變蛋白 48二) C-端二級結構部份缺失之SulA突變蛋白 50三) SulA不同性質胺基酸之點突變蛋白 51、討論 53、SulA蛋白被ClpY辨識之區域及其特性 53、不同蛋白酶對於辨認相同基質之差異 54、SulA突變蛋白之活性表現與FtsZ的相關性 55、ClpYQ蛋白酶對於SulA突變蛋白之降解情形 57、質體SulA的表現會誘導染色體之SulA表現 58、結論 60、參考文獻 61目錄一、本論文所使用的菌株與噬菌體 67二、本論文所使用的質體 68三、本論文所使用的引子對 69四、在酵母菌雙雜交系統中SulA突變蛋白與ClpY之交互作用情形 71五、SulA突變蛋白之活性測試及受ClpYQ蛋白酶降解之情形 72目錄一、大腸桿菌之SulA結構圖 73二、以酵母菌雙雜交系統分析Sul
A Study on the Attention-capturing Ability of Library Book Displays
No full text圖書館是保存文化、提供資訊、讓人可以從事終身學習與休閒閱讀的地方。為了推廣閱讀以及發揮館藏的價值，圖書館員致力於把館藏推薦給讀者，提升館藏的能見度，讓館藏被人所用。其中圖書展示是一種常用的管道。
如同零售業界的商品展示一樣，圖書館的圖書展示亦可運用各種陳列佈置技巧和行銷手法，提升展示的吸引力，爭取到更多讀者的駐足與青睞。尤其是視覺方面，是最容易且較會成功吸引注意力的途徑。因此從眾多視覺行銷的實務建議中，歸納出三項圖書展示陳列佈置的要點：
1.視線效果：優秀的陳列方式─像是將展品配置在與人視線同高之處─可以發揮展品本身的特色，吸引讀者靠近與選取。
2.焦點效果：展示營造出一個整體的畫面，且在畫面上有一個強調的焦點，搶先吸引到讀者的注意力。
3.內容效果：藉由陳列佈置的安排，充實展示的內容豐富性，提供各方面的訊息給讀者。
為檢驗上述三種吸引力效果的功效，本研究以臺北市萬興國小圖書館凱迪克得獎繪本展為背景情境，透過實驗法、觀察法以及焦點團體訪談法，測試三種圖書展示的陳列佈置技巧，分別為：直立或平放陳列、頒獎台與推薦插牌佈置、顏色分類陳列搭配內容簡介插牌佈置。探究其影響讀者注目、停留以及翻閱展品的閱讀行為。
結果發現在自由閱讀的圖書館情境中，若單就實驗法的T檢定結果，僅有繪本平放的視線效果是呈現顯著差異的，可能與平放的陳列方式比較符合兒童視線高度與瀏覽習慣有關；另外從焦點團體訪談也了解到繪本平放的優勢在於比較自然，較不會讓兒童有不敢取書的疑慮。而焦點效果和內容效果雖然在T檢定中皆沒有顯著差異，但若單純檢視位於圖書館走道中央的展桌之閱讀行為人次百分比，則會發現兩者的表現確實較佳，而且焦點團體訪談中大部分受訪者亦表示會受到頒獎台、推薦插牌、內容簡介的圖書展示方式吸引，因此可以認為焦點效果和內容效果仍有發揮一定程度的功效。以此作為圖書館在規劃圖書展示時的設計參考。Libraries provide a chance for life-long learning and leisure reading. To promote reading and make collections valuable, librarians strive to enhance the visibility of collections. One of means is the book display.
Just like the product display in the retail industry, library book displays can use many skills of layout and decoration to improve the attention-capturing ability. Sight is the much easier way to capture attentions in particular. Therefore, summed up many practical suggestions in visual merchandising, there are three effects of book displays:
1. Line-of-sight effect: putting books at the same height as the line of sight.
2. Focus effect: creating a focus in the overall picture.
3.Content-rich effect: providing information that is considered valuable to readers.
To test the attention-capturing ability of the three effects of book displays, this study was conducted with three experimental conditions. Using the special display of The Caldecott Medal picture books in an elementary school as a sample, this study tested the up-right display, flat display, podium display with recommendations and color-coded display with book introductions. This study recorded the number and ratios of passers-by, looking-at, stopping-by and picking-a-book. Besides, in order to understand motives and feelings of readers, this study did focus group interviews as well.
The findings show that only the flat display made a significant difference in the attention-capturing ability. It means that when the height of the book display is suit for children, line-of-sight effect will works. In addition, the subjects of focus group interviews mentioned that flat display makes it easy to get books. On the other hand, focus effect and content-rich effect didn’t show significant differences. But the ratios of looking-at, stopping-by and picking-a-book were better in the situation of podium display with recommendations and color-coded display with book introductions when the displays were setted at the table in the central aisle. Furthermore, the subjects of focus group interviews pointed out that they preferred these kinds of displays, because they thought they were attracting. It seems that focus effect and content-rich effect have a certain degree of attention-capturing ability. In conclusion, librarians can use line-of-sight effect, focus effect or content-rich effect to make a book display seems more charming.謝辭 iii
摘要 v
Abstract vii
目 次 ix
表 次 xi
圖 次 xiv
第一章 緒論 1
第一節 問題陳述 1
第二節 研究目的 2
第三節 研究範圍與限制 3
第四節 名詞解釋 3
第二章 文獻分析 5
第一節 消費者心理與購買決策 5
第二節 書店的圖書展示 22
第三節 圖書館的圖書展示 30
第三章 研究設計與實施 47
第一節 研究方法 47
第二節 研究步驟 70
第四章 結果與討論 71
第一節 展品陳列之視線效果 71
第二節 展品佈置之焦點效果 84
第三節 展品陳列佈置之內容效果 99
第四節 焦點團體訪談之研究結果 109
第五節 綜合討論 125
第五章 結論與建議 147
第一節 結論 147
第二節 建議 152
第三節 進一步研究之建議 155
參考文獻 159
附錄 169
附錄一：書展書單 169
附錄二：萬興國小閱讀課100學年度課表 172
附錄三：焦點團體討論大綱 17
Membrane repair induced HDAC6-independent autophagy and aggresome formation
No full text細胞因為機械壓力或外力所造成短細胞膜傷害，在細胞膜受傷後，細胞內會接觸到細胞外相對氧化的環境，造成胞內蛋白質被氧化形成蛋白質聚集(protein aggregates)。此外，細胞外Ca2+大量進入細胞內，促進液泡融合(vesicles fusion)或胞吐作用(exocytosis)於損傷處形成膜狀區塊，防止細胞內物質持續溢出細胞。之後細胞會進行胞吞作用(endocytosis)產生內吞體(endosome)移除細胞膜上的修補區域，而促進細胞膜的組成復原。目前還沒有人提出細胞膜傷害後，蛋白質聚集、膜狀區塊以及內吞體是如何被清除。篇論文中，利用磁珠滾動的方式大規模傷害細胞的細胞膜後，發現在滾珠後四小時會誘發自噬作用。若3-methyladenine (3-MA)抑制自噬作用則會使滾珠後細胞的存活率下降，顯示自噬作用可輔助細胞膜修補來增加細胞的存活率。此外，我們發現HDAC6不參與此類的自噬作用，而且此類的自噬作用並不幫助清除polyubiquitined proteins。由於蛋白質聚集、膜狀區塊以及內吞體沒有polyubiquitination，應該不是透過ubiquitin的途徑來降解，而且它們的分子量都很大，因此細胞滾珠後誘發的自噬作用可能可以幫助清除蛋白質聚集、膜狀區塊以及內吞體的機制。Transient plasma membrane disruptions commonly occur in cells that experience mechanical stress or external force. From what we have known, disruption of the plasma membrane would lead to the exposure of the cell interior to the external oxidizing environment and change the oxidation state of proteins in cells. These oxidized proteins would become extensively aggregated or cross-linked and attach to the disrupted plasma membrane. Furthermore, extracellular Ca2+ would enter cells, promoting vesicle fusion and exocytosis to form membrane patches that prevent cell contents from spilling out of cells. Afterward, damaged cells proceed to endocytosis and the formation of endosomes that promote the replacement of wound areas in plasma membrane. Protein aggregates, membrane patches, and endosomes that occur during plasma membrane disruption might cause cell stress. At present, it remains unclear how protein aggregates, membrane patches, and endosomes are eliminated in cells after membrane damage.ere, the results suggest that membrane damage at 4 hour after magnetic beads rolling is able to induce autophagy. By blocking autophagy with 3-methyladenine (3-MA), cell viability decreased after beads rolling. These results imply that autophagy participates in membrane repair. Moreover, we found that polyubiquitination and HDAC6 were not involved in the autophagic process following membrane damage and repair. Since ubiquitination plays a minimal role, autophagy, an alternative pathway caused by beads rolling, might help to eliminate protein aggregates, membrane patches and endosomes.目錄試委員會審定書謝 Ⅰ文摘要 Ⅱ文摘要 Ⅲ寫表 Ⅷ一章 前言一節 細胞膜修補(membrane repair) -1 細胞膜修補步驟 1-2 感應細胞膜受傷及液泡聚集 1-3 液泡融合和胞吐作用形成膜狀區塊 2-4 胞吞作用移除細胞膜上傷口 3-5 Tissue transglutaminase(TG)與細胞膜修補 3-6 Calcium phosphate binding protein-胎兒蛋白(Fetuin A) 4細胞膜修補二節 自噬作用(Autophagy)和自噬體(Autophagosome)-1 自噬作用的定義與形式 5-2 參與自噬體的蛋白質及marker 5-3 自噬作用藉由HDAC6抑制神經退化疾病 6三節 研究動機與目的 8 二章 材料與方法一節 細胞培養 9二節 細胞滾珠 9三節 cell lysate的萃取 9四節 SDS聚丙烯胺凝膠電泳[Sodium Dodecyl Sulfate－ 9olyAcrylamide Gel Electrophoresis (SDS-PAGE)] 五節 西方點墨法 (Western Blotting) 10六節 免疫螢光染色 (Immunofluorescence Staining) 11七節 建構EGFP-LC3 plasmid-1 引子(Primer)的設計 12-2 聚合酶連鎖反應 (Polymerase Chain Reaction, PCR) 12-3 洋菜膠電泳分析 (Agarose Gel Electrophoresis) 12-4 DNA去鹽 (Desalt) 13-5 DNA片段磷酸化 13-6 洋菜膠回收 13-7 PGEMT vector與DNA的接合反應(Ligation)和E. Coli細胞轉型 14 (Transformation) -8 菌落聚合酶連鎖反應 (Colony-PCR) 14-9 E. Coli液態培養 15-10 質體DNA(Plasmid)的抽取 15-11 核酸限制酶切割 (Digestion of Restriction Enzyme) 15-12 EGFP-C1 vector與DNA的接合反應 (Ligation) 15八節 細胞轉染 (Transfection) 16九節 MTT assay 16十節 藥物處理 17三章 實驗結果一節 細胞膜傷害後引起自噬反應 18二節 細胞膜傷害後引起適量的自噬作用可增加細胞存活率 19三節 HDAC6不參與細胞膜傷害後引起的自噬作用 20四節 細胞膜傷害後引起自噬作用不幫助清除polyubiquitined 21roteins 五節 細胞膜傷害後HDAC6立即減少並非進入細胞核內 22四章 討論一節 自噬作用與膜狀區塊和內吞體 23二節 自噬作用與氧化壓力 23三節 自噬作用與HDAC6 24四節 自噬作用與p38MAPK 24五節 HDAC6大量溢出細胞 25五章 圖表 1 細胞膜受傷後Fetuin A聚集在細胞膜表面隨後被清除 262 磁珠滾動傷害細胞的細胞膜後四小時誘發自噬作用 273 磁珠滾動傷害細胞的細胞膜後四小時利用免疫螢光染色觀察 28utophagosome 4 磁珠滾動傷害細胞的細胞膜後四小時利用細胞轉染EGFP-LC3B 29lasmid觀察autophagosome 5 磁珠滾動傷害細胞的細胞膜後四小時利用細胞轉染EGFP-LC3B plasmid及 30C3B免疫螢光染色觀察自噬體6 3-methyladenine(3-MA)抑制自噬作用與Rapamycin促進自噬作用對 31胞膜傷害後A431-Ⅲ細胞存活的影響 7 HDAC6對細胞膜傷害後引起自噬作用的影響 338 HDAC6不參與細胞膜傷害後引起的自噬作用 359 細胞膜傷害後引起自噬作用不幫助清除polyubiquitined proteins 3710 細胞膜傷害後HDAC6立即減少並非進入細胞核內 39六章 參考文獻 40七章 附錄錄1 Mitsugumin53 (MG53)可感應細胞膜受傷並促進細胞內液泡聚集 46錄2 Dysferlin可幫助液泡移動到細胞膜受傷的地方並促進液泡融合 47錄3 溶酶體(lysosome)是主要參與膜狀區塊形成的液泡 48錄4 液泡在細胞膜受傷的位置進行融合和胞吐作用，形成膜狀區塊 49錄5 Macroautophagy的形成 50錄6 mTOR pathway 51錄7 3-methyladenine (3-MA)抑制自噬作用 5
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
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