1,720,980 research outputs found
Gene expression of 14-3-3 family during zebrafish development and their overexpressions lead to the promotion of neurite outgrowth
No full text14-3-3是一種酸性蛋白，大小約25-30kDa，主要存在於腦部和神經性統中。它的功能廣泛，包含代謝，細胞週期的控制，訊息傳導，細胞凋亡，蛋白運送，轉錄，壓力反應及惡性轉型等。目前已知它和超過兩百種的受質結合，涵蓋細胞內幾乎所有的反應。本實驗根據其它物種比對所得之14-3-3序列來選殖斑馬魚14-3-3基因，並且收集資料庫中之其它已知的斑馬魚14-3-3序列，最後得到九種斑馬魚14-3-3蛋白家族成員，包括ζ，θ，β1，β2，β3，η，γ，ε1，以及ε2。經過胺基酸排序分析，親緣演化樹分析，基因結構分析，以及成對比較之結果，推論ζ，θ，β1，β2，及β3親緣關係較接近，屬於第一群；η和γ為第二群；ε1及ε2則為第三群。利用全胚胎原位雜交法分析斑馬魚14-3-3家族之mRNA在受精後六小時到一百二十小時的胚胎表現分佈位置，結果發現它們在腦部之表現量最多，其次則是視網膜，鰓，以及腸道。將斑馬魚14-3-3的九個基因以顯微注射方式表現在斑馬魚早期胚胎中，結果在受精後48小時，只有14-3-3 β3可觀察到明顯的神經纖維生長現象。將14-3-3 β3作R56A及R60A雙突變以破壞14-3-3和受質的結合，或是將14-3-3 β3與蛋白質去磷酸酶PP2A一同表現以使受質去磷酸化，均可有效抑制神經纖維生長的情形。而隨著MEK (MAPKK) 抑制劑PD98059的增加，神經纖維生長的抑制越明顯。將斑馬魚的Rho GTPase家族中的Rac-1及Cdc42均作T17N突變，和14-3-3 β3一同注射到斑馬魚胚胎中，也是隨著注射劑量增加，抑制神經纖維生長的效果越明顯。故由以上結果，推測斑馬魚14-3-3 β3和受質結合後，是經由MEK及MAPK路徑而使神經纖維生長，然而Rac-1及Cdc42在路徑中作用的位置則尚未明瞭。14-3-3 family proteins are adaptor proteins that specifically bind to a discrete phosphoserine or phosphothreonine motif in the substrate proteins. They play important roles in metabolism, cell-cycle control, signal transduction, apoptosis, protein trafficking, transcription, stress responses, and malignant transformation. They are found only in eukaryotes. In this study, I cloned and characterized 9 genes encoding nine members of zebrafish 14-3-3 family, designated theta (θ), zeta (ζ), beta1 (β1), beta2 (β2), beta3 (β3), eta (η), gamma (γ), epsilon1 (ε1), epsilon2 (ε2). Amino acid sequence alignment and phylogenetic tree analysis indicated that all zebrafish 14-3-3 members can be divided into three group. The ζ, θ, β1, β2 and β3 belong to Group I, while η and γ Group II. In addition, ε1 and ε2 are the third. Using whole-mount in situ hybridization to analyze the mRNA expression profile of zebrafish 14-3-3 family from 6 hpf to 120 hpf, the signal was found primarily in the brain while moderate in retina, gill and gut. Expression of GFP-fusion protein of each isoform of zebrafish 14-3-3 family by a neuron-specific HuC promoter in zebrafish embryos indicated that only 14-3-3-beta3 isoform could promote neurite outgrowth. A double mutant of 14-3-3-beta3 (R56A and R60A) abolished this effect. Coinjection of pHuC-14-3-3-beta3-HuC-GFP with protein phosphatase 2A (PP2A), Cdc42 dominant negative form (Cdc42-T17N), Rac1 dominant negative form (Rac1-T17N) and MAPKK inhibitor PD98059, respectively, reduced the neurite outgrowth induced by 14-3-3-beta3.目錄
中文摘要…………………………………………………………...….......................
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英文摘要 (Abstract)…………………………………………….….........................
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縮寫表………………………………………………………….......….......................
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目錄…………………………………………………………...........….......................
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表目錄………………………………………………………………………………..
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圖目錄………………………………………………………………………………..
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壹、序言……………………………………………………………..........................
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一、14-3-3的基本背景………………………………………………………….
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二、14-3-3的蛋白質結構……………………………………………………….
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三、14-3-3蛋白的作用機制…………………………………………………….
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四、14-3-3目標結合的調控…………………………………………………….
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五、不同物種間的14-3-3蛋白家族……………………………………………
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六、14-3-3蛋白家族在不同組織的表現分布………………………………….
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七、14-3-3對於人類神經性及腫瘤相關疾病的影響………………………….
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八、Rho GTPase 家族……………………………………………………...…...
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九、研究目的及策略……………………………………………………………
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貳、實驗材料與方法………………………………………………………………..
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I. 實驗材料……………………………………………………………....………
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II. 實驗方法……………………………………………………………………..
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一、斑馬魚14-3-3基因之選殖…………………………………………………
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二、斑馬魚胚胎之顯微注射…………………………………………………….
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三、斑馬魚14-3-3 mRNA在早期胚胎發育之表現：RNA全胚胎原位雜交 (RNA whole-mount in situ hybridization) ………………………………….
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參、結果…………………………………………………………..............................
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I. 斑馬魚14-3-3基因家族序列………………………………………………...
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一、選殖及分析斑馬魚14-3-3基因家族………………………………………
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二、斑馬魚14-3-3基因家族成員的親緣演化關係……………………………
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II. 斑馬魚14-3-3在不同胚胎發育時期的表現位置及表現量………………..
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一、斑馬魚14-3-3 ζ mRNA的表現分布……………………………………….
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二、斑馬魚14-3-3 θ mRNA的表現分布……………………………………….
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三、斑馬魚14-3-3 β1 mRNA的表現分布……………………………………..
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四、斑馬魚14-3-3 β2 mRNA的表現分布……………………………………..
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五、斑馬魚14-3-3 β3 mRNA的表現分布……………………………………..
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六、斑馬魚14-3-3 η mRNA的表現分布……………………………................
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七、斑馬魚14-3-3 γ mRNA的表現分布…………………………….................
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八、斑馬魚14-3-3 ε1 mRNA的表現分布……………………………………..
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九、斑馬魚14-3-3 ε2 mRNA的表現分布…………………………………..…
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十、綜合斑馬魚14-3-3各isoform的表現分布………………………………..
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III. 斑馬魚14-3-3基因家族影響神經纖維生長及其相關基因……………….
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一、過度表現斑馬魚14-3-3基因家族…………………………….……………
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二、斑馬魚14-3-3基因家族過度表現所導致神經纖維生長之比例…………
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三、抑制斑馬魚14-3-3 β3 和受質的結合會減少神經纖維的生長…………..
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四、MEK抑制劑可突變減少斑馬魚14-3-3 β3所導致之神經纖維生長的情形……………………………………………………………………………
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五、Cdc42及Rac-1的突變會抑制斑馬魚14-3-3 β3所導致之神經纖維生長的情形……………………………………………………………………....
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肆、討論……………………………………………………………………………..
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Study on the Taxi Amount in Urban Area
No full text計程車為都市內公共運具之一，被歸類為副大眾運輸，可輔助大眾運輸不足與移轉私人運具旅次使用，隨都市發展，角色更形重要。截至2002年年底，整體台北都會區計程車總數達66,321部。公路法中，規定依照人口與道路面積成長比例發放計程車牌照，台北營業區之標準為每120名人口新增乙付牌照。調查結果顯示，實際之空車率遠高於合理空車率，2002年台北地區之距離空車率達59.8％，原因實與計程車數目過量有關。本研究期望利用數學分析方法，並輔以現況調查資料，推算所需計程車車輛數，並據此探討逐步降低計程車車輛數之辦法，以提供都會區計程車數量管制決策之參考。
本研究希望能在同時考慮計程車旅次需求與駕駛員合理維生之下，求算都會區所需計程車車輛數之上下限。首先求算都會區每日計程車人旅次總數；再分別以駕駛員合理收入或駕駛員合理工作時間為原則，計算單位計程車之最低與最高臨界服務量；最後將兩者相除即得所求。
結果顯示，2000年台北都會區每日計程車總旅次數為115,996人次，每部車輛每天至少需服務41.56人旅次 ，即28車旅次，才達收支平衡，故最高約需33,600部計程車營業載客。而每部計程車一天最多可服務約45人旅次，即30車旅次，最低所需計程車數為31,000部。介於31,000部與33,600部間均屬合理。
依據車輛依法課徵「使用」牌照稅。且計程車管理規則中，亦有牌照不得轉讓或轉賣之規定，因此認為政府實質上具有計程車牌照之所有權，計程車牌照應為政府「無償授與」之營業許可證，可當作為資格符合的憑證。因此政府應有資格於牌照被不當使用或放棄使用時將之註銷收回。另外尚建議不應有價回收牌照、車輛使用年限為6年、個人車行牌照只收不發、引入營運許可年限等計程車數量管制相關辦法。Abstract目錄
中文摘要 一
目錄 二
圖目錄 五
表目錄 六
第一章 緒論 1
1.1研究背景與動機 1
1.2研究範圍與目的 2
1.3研究方法與流程 2
1.4論文章節說明 5
第二章 文獻回顧 6
2.1計程車供需數量與空車率 6
2.2計程車數量管制理論 7
2.3計程車管理相關法規 8
第三章 臺北都會區計程車現況分析 14
3.1計程車數量發展沿革 14
3.1.1車輛登記數 14
3.1.2職業駕駛員登記數 19
3.1.3臺北市人口與計程車車輛數 20
3.2計程車營業情形 21
3.2.1計程車營業區域劃分 21
3.2.2計程車行車成本 23
3.2.3計程車營運狀況 23
3.3計程車使用狀況 31
3.3.1個別旅次使用狀況 31
3.3.2計程車旅次特性分析 36
第四章 計程車數量推算方法 39
4.1以維持駕駛員之合理收入為原則 39
4.1.1推算變數設定 39
4.1.2計程車數量推算 41
4.2以駕駛員之合理工作時數為原則 44
4.2.1推算變數設定 44
4.2.2計程車數量推算 46
4.3台北都會區計程車所需數量 49
4.3.1 2000年調查資料推算結果 49
4.4敏感度分析 54
4.5預測2005年台北都會區計程車需求數量 58
4.5.1未來年推算過程所需參數之預估 59
4.5.2 2005年台北都會區所需計程車數量預估 61
第五章 數量管制方法研定 64
5.1計程車數量管制之重要性 64
5.2管制方法研擬 65
5.2.1現行計程車組織 66
5.2.2計程車牌照所有權以及使用權歸屬釐清 67
5.2.3數量管制時程與目標研擬 68
5.2.4牌照有價回收並不可行 70
5.2.5計程車管理引入營運期限許可規定 71
5.2.6計程車牌照重新核發申請辦法 72
5.2.7計程車客運業營運車輛車齡限制 73
5.2.8個人車行牌照只收不發 75
5.2.9其他 76
第六章 結論與建議 78
6.1結論 78
6.2建議 79
參考文獻 8
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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