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Study the Effect of IGFBP5 in Human Fibroblast Cells
No full text放射治療已被應用於治療多種癌症，視網膜母細胞瘤就是其中之一。然而，罹患遺傳性視網膜母細胞瘤的孩童其外表正常的雙親之皮膚纖維母細胞會對游離放射線產生預期外的高敏感性(hypersensitivity)現象。Dr. Chuang 等人於2006 年利用 DNA 微陣列晶片技術分析並挑選出42 個與游離輻射誘發細胞敏感度改變有關之基因。IGFBP5 (insulin-like growth factor binding protein 5)是42 個游離輻射敏感性相關的基因之一，此基因被選出並探討其在人類纖維母細胞中造成之細胞輻射敏感度效應。此外，IGFBP5 已被證實與內皮細胞之老化有關。因此，本論文之主題為研究IGFBP5 基因在人類纖維母細胞中造成的游離輻射敏感性及細胞老化之效應。
本篇研究顯示，IGFBP5 與人類纖維母細胞老化有關，此結果是經由老化相關特定酵素染色(SA-β-gal staining)、細胞增生分析、以及分析微陣列實驗數據得到與抗細胞增生、細胞週期中止以及細胞老化之相關基因得知。此外，IGFBP5 與人類纖維母細胞之游離輻射敏感度有關：經由細胞聚落形成分析(colony formation assay)得知，大量表現IGFBP5 之人類纖維母細胞 Hs68 其對於2 Gy 到4 Gy 的游離輻射有較高的耐受性。本篇實驗結果顯示，IGFBP5 造成人類纖維母細胞對輻射耐受性增加，是因為此基因使得細胞增生速率變慢，以及從微陣列實驗數據分析得知其間接活化PI3K-AKT 細胞訊息傳遞路徑有關。Radiotherapy is commonly used for the treatment of many kinds of cancer such as retinoblastoma. However, an unexpected hypersensitivity to ionizing radiation in skin fibroblasts derived from unaffected parents of children with hereditary retinoblastoma was observed. The results from Dr. Chuang et al. used DNA microarray technology to select the 42 significantly differential expressed genes and identified as radiosensitive genes were observed in 2006. IGFBP5 (insulin-like growth factor binding protein 5), one of these 42 genes, was chosen to further investigate the role in radiosensitivity in fibroblast cells. In addition, IGFBP5 was reported that it was involved in the cellular senescence in endothelial cells. As the result, the topic of this thesis was to evaluate the role of IGFBP5 in radiosensitivity and cellular senescence in human fibroblast cells.
The results of this study showed IGFBP5 was involved in senescence by the method of SA-β-gal staining, cell proliferation assays, and the identification of genes related to anti-proliferation, cell-cycle arrest and senescence by the analysis of array data. Also, IGFBP5 played a role in radiosensitivity: Hs68 IGFBP5-overexpressed cells were more resistant to radiation at 2-4 Gy verified by colony formation assays. The radioresistace of IGFBP5 might be the lower proliferation rate of Hs68 IGFBP5-overexpressed cells and the up-regulation of PI3K-AKT pathway found from the analysis of array data
Using a simplest passive walking model to analyze the friction force and the slip boundary
No full text近年來，老年人的比例日益增加，而跌倒成為老年人一個很普遍且嚴重的問題。每一年，有將近三分之一的老年人曾經發生跌倒的情況，而這些跌倒的老年人中又有二分之一甚至跌倒超過一次。跌倒會造成許多後續的問題，而其中最重要的是，跌倒造成了龐大的社會成本。在預防勝於治療的理念下，本論文希望能藉由模擬長者走路時磨擦力與正向力之關係，了解產生可能產生滑倒之情況，並探討產生滑倒之臨界狀況，以期能預防並減少長者滑倒的機率，以減少因跌倒而產生之巨大的社會成本。由文獻我們發現，老年人走路時，下坡比下樓梯更容易造成危險，因此，本論文將探討老年人走在斜坡上之受力情況。
首先，我們建立一最簡被動走路模型，此模型的腳為點狀，並具有兩支無膝蓋之腳，每支腳具有一點質量，而第三個點質量為上半身之質量集中在臀部。此模型具有兩個自由度，分別在站立腳之腳底與斜坡之接觸點，其角度為從水平至站立腳之角度；另一自由度則在臀部之關節，其角度為從水平至搖擺腳之角度。此外，此模型具有四個狀態變數，分別為兩個角度以及其微分值。我們利用尤拉拉格朗日法找出此最簡被動走路模型之動態方程式，並利用Matlab將狀態變數之初始值代入，利用不斷的積分以及迭代，我們即可得到在每一間隔時的狀態變數之值。當搖擺腳之腳底與地面產生接觸時，衝擊會產生並造成角速度之不連續。我們假設衝擊產生時，站立腳與搖擺腳互換之時間非常小，並由於沒有受到其他外力，在換腳的過程中，整體系統對接觸點之角動量和後腳對臀部關節的腳動量皆會守恆。由於此動態方程式之參數很多，為了將參數減少，我們定義了三個無因次的參數，並假設站力腳與搖擺腳之質量相等。因此藉由調整質量比和長度比，我們可得到不同的走路模型。最後，我們利用此走路模型對摩擦力進行分析，若磨擦力之值小於正向力乘上最大靜摩擦係數之值，則我們可推論此走路模型不會產生滑倒之現象。
我們利用極限圈和Poincare圖進行走路模型之週期解的探討，並利用不同的無因次化參數去觀察極限圈改變之情形;而在一走路週期中，由於沒有受到其他外力，因此總能量會守恆，但在產生衝擊時會產生消散，此消散之能量則用位能去彌補;最後利用力平衡之概念找出行走一步時磨擦力與正向力之值，由其比值找出所需之地面的摩擦力係數。
為了簡化走路模型，我們可將此走路模型簡化成倒單擺模型，此倒單擺之重量和走路模型之重量相等，而其受力則為走路模型的合力。由於在走路過程中，此走路模型不是剛體，因此造成力矩之不相等，若我們假設走路之過程非常緩慢，則此誤差則可忽略。In recent years, the population of elders is increasing day by day and the fall of elders has become a common and serious problem. Nearly one third of elders fall each year and half of these elders fall more than once. Fall caused lots of problems. The most important is that falls cause a huge economic burden. In the concept of prevention is better than cure, it is highly desired to prevent and reduce the probability of elders falling so that the huge economic burden which is caused by falls can be reduced. In this thesis, it is attempted to simulate the slip situation and to find the slip boundary. According to literatures, the risk of walking downward a hill is higher than downward a stairs. Thus, in this paper, the forces when the elders walk downward a hill are investigated.
First, we built a simplest passive walking model on an inclined slope. The passive walking model has two point feet and two knee-less legs each having a point mass. It also has a third-point mass at the hip joint which represents the mass of upper body. The walking model has two degrees of freedom. One is at the sole of stance leg from horizontal to the stance leg, and the other is at the hip joint from horizontal to the swing leg. The walking model has four state variables which are the two angles and the differential of the angles. Euler-Lagrange equation is used to find the equations of motion of the passive walking model. Then, the initial conditions of the four state variables are given in Matlab so that the value of state variables can be derived at each moment with regular internal by interative integration. When the sole of the swing leg contacts with the inclined slope, impact occurs and the angular velocities become discontinuous. We assume that when impact occurs, the duration of leg change is infinitesimally small. Thus, the angular momentum of the whole system to the contact point and that of the rear leg to the hip joint are conserved. Because there are too many parameters in the equations of motion, we defined three dimensionless parameters and assumed that the masses of the stance leg and legs are equal. We can obtain different walking models by varying the dimensionless parameters which are the mass ratio and the length ratio, respectively. Finally, we can analyze the slip situation by finding the friction force and normal force during walking. If the value of friction force is smaller than the value of normal force multiplying the coefficient of static friction, we can conclude that the walking model is under a non-slip situation.
In this thesis, we use limit cycle and Poincare’s map to determine whether there are periodic solutions or not. Different slopes and mass ratios are given to investigate how the limit cycle changes. The total energy of the passive walking model is conserved in a walking cycle and is dissipated when the inelastic impact occurs. During a walking cycle, the kinetic energy and the potential energy convert to each other. Finally, we use the force balance to find the normal force and friction force during a step and use the ratio of the friction force and normal force to find the needed coefficient of static friction.
In order to simplify the walking model, we can use an inverted pendulum whose mass is the total mass of the walking model. The force acting on the inverted pendulum is the resultant force of the walking model. Because the whole system of the walking model is not a rigid body, the moment of the inverted pendulum is different from that of the walking model. Thus, the slip boundaries between these two models should be different. If we assume the walking model moves very slowly, then the discrepancy of the slip boundaries would be tolerable
From a Good Wife and a Loving Mother to a Fearless Warrior: A Study of Female Military Training in Wartime Taiwan, 1937-1945
No full text女性向來扮演著賢妻良母的角色。女性在日治時期非徵兵對象，但日本政府卻在日本本土與臺灣實施女性的軍事訓練，本研究欲探其政策之原因、內容與實施狀況。本研究以歷史研究法為主，訪談為輔，蒐集史料並分析前因後果，客觀地解釋史料。本研究時間訂為1937-1945的戰爭時期，探究戰爭中女性與國家的關係，釐清臺灣女性軍事訓練的意義，並了解戰爭時期臺灣女性各種處境與女性在社會上可以發揮的空間。 日治時期女性的動員政策可分成三種，一是政府強調女性當母親的特質，二是女性要做防空演習，三是女性有軍事訓練。女性軍事訓練包含「軍事教練」與「武道」兩部分，實施對象有學生與一般婦女。 政策制定的原因在於日本素有「國民皆兵」理念，國民注重健康才能隨時面對戰爭。因此在戰爭時期，日本政府注重國民心身的鍛鍊與推行女性軍事訓練。女性軍事訓練有射擊、行軍、合宿、武術（薙刀、弓道、劍道）、木銃、銃劍術、馬術、竹槍。日本政府期盼女性藉由軍事訓練鍛鍊身心與體能，孕育健康的子女，也希望女性能由此增加軍事知識。由於日本的戰況趨劣，女性學習基本的軍事也能夠做鄉土防衛。最後，政府也希望女性也藉由軍事訓練以激發對士兵的感謝。對女性來說，無論是增強體能或是鄉土防衛，女性的身體終究是聽命於國家。 女性也因為軍事訓練，形象也有了轉變。女性武勇形象表現在女性對兵器的熟悉、愛國的熱情，以及勇敢的展現。但女性就算有了武勇的形象，卻也並未失去原本賢妻良母的原本職責，兩者並未衝突。日本政府藉著在報章雜誌刊登關於女性的軍事訓練報導，企圖藉此影響男性視聽，增加男性的報國意願。女性在軍事訓練的過程中，也獲得自我反思的契機，對軍國主義教育有了思考與反省。Abstract The role of women has traditionally been that of a good wife and a loving mother. While females were not generally conscripted, women in Japan and Taiwan sometimes received military training from programs implemented by the government. Following an historical approach, this study explores the factors, contents, effects, and causal links of such policy. This study also endeavors to ensure the objective interpretations of historical facts through collection of oral histories. The time period of this study covers the entire war-time era from 1937 to 1945, so as to investigate the relationship between females and the nation during wartime, clarifying the meaning of military training for Taiwanese women and understanding the various situations and potentials of Taiwanese females. The policy of mobilizing females during Japanese rule could be delineated into three dimensions. First, the emphasis of female’s role as a mother; second, their participation in air defense drills; and third, receipt of military training. Female military training in this case included “basic military training” and “budō,” particularly the use of naginata, kyudō, and kendō. Students and women in general were both included in the programs. The rationale of this policy for female participation in military training is derived from the concept of “the nation in arms” from Japan. According to this idea, citizens must maintain health-consciousness in order to be prepared to readily face any contingency during wartime. Therefore, during wars, the Japanese government implemented the policies of “national mental and physical exercises” and “female military training.” The female military training included shooting, marching, room sharing, budō, spears, the crafting of bamboo spears and spear fencing, and equestrianism. The Japanese government expected that through such military training, women could not only build a strong physique in order to maintain mental health and raise healthy children but also enhance their military knowledge. As the battlefield situation had gotten worse, females receiving military training would also serve to bolster domestic defenses as well. Eventually, through the training, the government also expected that females should rouse gratitude towards the soldiers. No matter training for own personal health or domestic defense, the females were dominated by the government. Military training also reshaped women’s role and image. The familiarity of weapons, patriotic and fearless acts exemplified the bravery of women. However, such images were not incompatible with their roles of being a good wife and loving mother. The Japanese government utilized the news of female training to serve as an element of propaganda in order to inspire males’ jingoism. The military training granted females chances of introspection toward themselves and a re-examination of the education of militarism. Keywords：a good wife and a loving mother, wartime, basic military training, budō, the nation in arms, domestic defens
A Competition Model for Mining Cryptocurrencies
No full text過往文獻所提出的競爭模型，只能讓消費者從競爭廠商中選擇一個提供較高效益的商品。然而，在密碼幣市場中，挖礦者可同時挖掘數種密碼幣，不受限於只能選擇一種密碼幣。因此，在本篇論文中，我們提出一權重式選擇模型以探討密碼幣的競爭情形，其中，每一位挖礦者可投注部份資源於一個密碼幣，再將剩餘資源投注於另一個密碼幣。此模型延伸了過往貨幣文獻中以網路外部性建構密碼幣的價值，並將挖礦成本、外部風險以及挖礦者對於挖礦效用的敏感度納入考量。有別於過往所提出的非權重式選擇模型(勝者全拿)，我們的權重式選擇模型將挖礦者所投注的小部份資源納入考量，使得較小的密碼幣，即使沒有網路外部性優勢，依然可以透過從每一挖礦者所蒐集的小部份資源而生存。另外，分析結果亦顯示，若採用權重式選擇策略，密碼幣基金會更能克服嚴峻的競爭情形，且挖礦者亦可獲得更高的效益。本研究的成果可提供挖礦者策略性的洞見，並幫助密碼幣基金會制定競爭策略以運作其密碼幣。Many previously proposed competition models only allow consumers to choose a product with a higher utility, provided by just one of the competitors. However, in cryptocurrency market, miners are allowed to mine multiple cryptocurrencies simultaneously, not just limited to one. Therefore, in this thesis, we propose a weighted effort model to study the competition between two cryptocurrencies, where every miner is allowed to allocate some efforts to one cryptocurrency and the rest to the other. The proposed model extends the concept of the previous currency studies by using the network benefit to model the value of a cryptocurrency, and takes mining cost, exogenous risk, miners’ intrinsic mining benefit sensitivity into account. Unlike previously proposed un-weighted effort models (winner-take-all), our weighted effort model takes the small amount of efforts collected from miners into account, and shows that the smaller cryptocurrency can survive by aggregating the small amount of efforts even though it doesn’t have the advantage of network benefit over its competitor. It also shows that foundations are more likely to overcome stiff competition and miners can obtain higher utilities if weighted effort strategy is adopted. The analytical results can provide some strategic insights for miners and help foundations formulate competitive strategies to run their cryptocurrencies.Table of Contents i
List of Figures ii
List of Tables iii
Chapter 1 Introduction 1
Chapter 2 Literature Review 7
Chapter 3 Model Setup 11
3.1 Miners’ and Foundations’ Formulations 12
3.2 Timeline of Model 13
Chapter 4 Equilibrium and Analysis 15
4.1 The Equilibrium 15
4.2 Impact of Risk Ratio and Unit Mining Cost 21
4.3 Discussions on Cryptocurrency Market Competition 28
4.4 Un-weighted Effort Model 34
Chapter 5 Conclusions and Future Work 39
Appendix A 42
References 4
Role of matriptase-2 in human prostate cancer migration and invasion.
No full text癌症轉移是導致癌症病人預後不佳及死亡率上升的主要原因。第二型細胞間質蛋白酶[(Matriptase-2 (MTX2)]，隸屬於第二型穿膜絲胺酸蛋白酶家族(TTPSs)，與第一型細胞間質蛋白酶[(Matriptase (MTX)]具高度相似性。先前報導指出MTX2可能抑制癌症細胞功能，然而其詳細的機制仍然不清楚。為了進一步探討MTX2如何抑制攝護腺癌細胞的移動與侵襲能力，我大量表達Matriptase-2在攝護腺癌細胞中(PC3 和DU-145)，並發現此蛋白酶可明顯地降低攝護腺癌細胞的侵襲和移動能力。因先前報導指出上皮細胞轉形成間葉細胞的過程(epithelial mesenchymal transition (EMT))在癌症的轉移進程中扮演重要的角色。利用QRT-PCR得知，在表達MTX2之PC3細胞中，EMT相關的轉錄因子基因(Twist, SIP-1)表現量都下降，且 MMP9 (Matrix metallopeptidase 9)的基因和活化程度也隨之降低，這些結果顯示MTX2可藉由改變EMT來抑制攝護腺癌細胞的移動能力。轉化生長因子β（TGF-β）已被報導為強效性的EMT促進者。而利用西方點墨法發現典型的TGF-β訊息傳導下游的Smad2及Smad3之蛋白質量和磷酸化程度因MTX-2的表達而下降。此外，上皮生長因子受體(EGFR)的磷酸化程度也隨之下降，因此而探討MTX-2是否可影響其他膜上蛋白酶，進而降低癌細胞的侵襲力，由於先前研究指出MTX與攝護腺癌細胞的轉移有很大的關係，我也探討MTX2和MTX之間是否會影響。結果顯示在表達MTX2的PC3細胞，MTX的基因和蛋白質表現量都是明顯的下降。同時MTX2會促進MTX被分泌到細胞外。綜合以上結果，MTX2可藉由降低TGF-β訊息路徑下游分子之活化，抑制EGFR磷酸化以及MTX的表達，故MTX2扮演具抑制攝護腺癌細胞侵襲的角色。Metastasis is often associated with a poor prognosis and isa leading cause of cancer mortality in prostate cancer. Matriptase-2 (MTX2) is a member of the type II transmembrane serine protease (TTSP) family and has a similar domain structure to matriptase which can enhance cancer cell invasion and migration. Some research results have indicated that MTX2 functions as a tumor suppressor. However, the molecular mechanisms by which MTX2 plays a negative role in prostate cancer are still unclear. In this study, examination the role of MTX2 in prostate cancer cell migration and invasion by ectopic expression of MTX2 in prostate cancer cells (PC3 and DU145). Data suggested that MTX2 reduced cell invasion and migration of PC3 and DU-145 cells. Moreover, MTX2 could down-regulate the mRNA levels of Twist, SIP-1, and the expression and gelatinolytic activity of MMP9, suggesting the involvement of MTX2 in altering an epithelial mesenchymal transition (EMT)-like event. Moreover, to further analyze if MTX2 was involved in modulating the TGF-β signaling pathway, a strong EMT inducer, we found that both protein and phosphorylation levels of TGF/BMP signaling effectors, Smad2 and Smad3, were decreased in MTX2-overexpressing cells. Furthermore, the ectopic expression of MTX2 also decreased the phosphorylation levels of epidermal growth factor receptor (EGFR), and was concurrent with a reduction of the gene and protein levels of matriptase, an oncogenic membrane-anchored serine protease in prostate cancer PC3 cells. Taken together, the data indicate that MTX2 functions as a suppressor of prostate cancer cell migration and invasion, at least in part via reducing the protein and phosphorylation levels of Smad2 and Smad3, the phosphorylation of EGFR, or the expression and activated levels of MTX
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
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