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The Effect of the Ocean Eddy on Tropical Cyclone Intensity
No full text2005年超級颶風Katrina侵襲美國紐奧良地區，重創美國經濟民生。觀測發現Katrina在經過墨西哥灣的暖水域(Loop Current)時，強度自第二級颶風快速地增強到第五級颶風。值得注意的是，除了Katrina外，無論在太平洋或大西洋上許多超級颱(颶)風，如2003年太平洋上的超級颱風Maemi及2005年大西洋上的超級颶風Rita，都被觀測到它們在經過海洋的暖渦或暖洋流(warm eddies or Loop Current)時明顯迅速增強 (rapid intensification)。這樣的快速增強過程，到目前為止是數值模式所無法完全掌握的，更遑論預報。本研究主要的目的即是討論不同的海水熱力結構（特別是海洋中存在的暖渦）對颱風強度有何重要的影響。
研究中使用一個理想的海氣耦合模式，模擬颱風在不同海洋結構中的發展。模擬結果發現，不同的海洋結構會影響到颱風所引起的海洋負回饋的強度，進而影響到颱風的最終強度。此研究同時也模擬颱風遭遇到暖渦時的反應，採用兩個回饋指數 -- FEDDY-S與FEDDY-T，來進一步地量化並探討海洋暖渦對颱風強度的影響程度。結果顯示當颱風遇到暖渦時，颱風的強度會快速增強，因為暖渦能夠提供較多的表面熱通量，且颱風所引起的海洋負回饋作用也因為暖渦深厚的混和層所產生類似絕緣體的角色(隔絕颱風與混和層下方的冷海水)而遭到抑制。 另外我們也利用大量的數值實驗及最小方差近似得到FEDDY-T與模式參數的相關性，由此並發現混和層厚度是個相當具有影響性的環境參數，其次為颱風移動速度與環境相對濕度。 研究中也討論當颱風遇到海洋冷渦時的反應，結果發現冷渦與暖渦對颱風強度影響相反但程度卻相當類似。The rapid intensification of Hurricane Katrina along with a devastating hit to the southern states of the U.S. is a case in point to highlight the critical role that the upper oceanic thermal structure (such as the ocean eddy or Loop Current) plays in affecting the development of tropical cyclones. In this thesis, the impact of the ocean eddy on tropical cyclone intensity is investigated using a simple hurricane-ocean coupled model.
Numerical experiments with different oceanic thermal structures are designed to elucidate the responses of tropical cyclones encountering the ocean eddies and the influence of tropical cyclones on the ocean. This simple model shows that rapid intensification occurs in a storm encountering the ocean eddy due to enhanced heat flux. While strong wind usually causes strong mixing in the mixed layer and thus cools down the sea surface, such a negative feedback to the storm intensity is limited at the presence of warm ocean eddy which provides insulating effect against the storm-induced mixing and cooling.
Two eddy factors, FEDDY-S and FEDDY-T, are defined to evaluate the effect of the eddy on tropical cyclone intensity. The efficiency of the eddy feedback effect depends on both the oceanic structure and other environment parameters, including properties of tropical cyclone. Analysis on the functionality of FEDDY-T shows that the mixed-layer depths of the large-scale ocean and of the eddy are the two most important factors determining the magnitude of eddy feedback effect. Next to them are the storm’s translation speed and the ambient relative humidity. In contrast to warm ocean eddies, cold ocean eddies impede storm’s intensification and even reduce storm’s intensity. The impact of the cold ocean eddy is similar in magnitude but opposite in sign to that of the warm ocean eddy.Table Captions iii
Figure Captions iv
Chapter 1 Introduction 1
1.1 Background and Motivation 1
1.2 Objectives 3
Chapter 2 Methodology 4
2.1 The Sea Surface Temperature Feedback Factor (FSST) 4
2.2 The Eddy Feedback Factors (FEDDY-S and FEDDY-T) 5
2.2.1 FEDDY-S: 5
2.2.2 FEDDY-T: 6
Chapter 3 Experiment design 7
3.1 Experiment A – Impact from the assimilated profiles of the NPACNFS 7
3.2 Experiment B – Sensitivity tests of some key parameters 8
3.3 Experiment C – Evaluation of the warm eddy’s role 8
3.3.1 TC encountering the perpetual warm ocean eddy 8
3.3.2 TC encountering a transient warm ocean eddy 9
3.3.3 Comparison of the values of FEDDY-T between the model and the real-case storms 9
3.3.4 A general function for FEDDY-T 10
3.4 Experiment D – Evaluation of the cold eddy’s role 10
3.4.1 TC encountering a transient cold ocean eddy 10
3.4.2 Comparison of the eddy feedback effects between the warm and cold eddies 10
Chapter 4 Experiment Results and Discussions 12
4.1 Control Experiment 12
4.2 Experiment A – Impact from the assimilated profiles of the NPACNFS 13
4.3 Experiment B – Sensitivity tests of some key parameters 15
4.3.1 Impact from the SST 16
4.3.2 Impact of the mixed-layer depth 16
4.3.3 The impact of DT and the lapse rate (G) of upper thermocline 17
4.4 Experiment C – Evaluation of the warm eddy’s role 18
4.4.1 TC encountering the perpetual warm ocean eddy 19
4.4.2 TC encountering a transient warm ocean eddy 22
4.4.3 Comparison of the values of FEDDY-T between the model and the real-case storms 25
4.4.4 A general function for FEDDY-T 26
4.5 Experiment D – Evaluation of the cold eddy’s role 30
4.5.1 TC encountering a transient cold ocean eddy 30
4.5.2 Comparison of the eddy feedback effects between the warm and cold eddies 31
Chapter 5 Conclusion and Future Work 33
5.1 Conclusion 33
5.2 Future Work 35
Appendix A-Model description 37
A.1 Hurricane Model 37
A.2 Ocean Model 48
A.3 Coupled Model 52
Reference 5
A Study on Identification of Opinion Holders and Analysis of Their Viewpoints
No full text意見代表人們對某個議題的主觀想法，人們常透過文章表述意見，意見探勘 (opinion mining) 的技術可以幫助使用者自動分析大量文章中的意見。意見包括意見傾向 (opinion polarity) 、意見強度 (opinion strength) 、意見持有者 (opinion holder) 及評論目標 (opinion target) 四個要素。意見中表述意見的人或組織稱為意見持有者，意見持有者在不同議題中發表過的意見代表他的意見立場。在意見探勘中，意見持有者辨識的技術對於了解有哪些人或組織在表述意見、某個意見持有者的意見立場及兩個意見持有者的意見立場是否相似等相關資訊特別重要。意見持有者辨識主要有五個挑戰：同指涉解析 (coreference resolution) 、巢狀結構 (nested structure) 、處理歧異的標記、完整的意見持有者及候選詞選擇。見持有者辨識的目的是從意見句中擷取表述意見的人或組織，本研究提出一個以機器學習為基礎的意見持有者辨識方法。本研究將意見持有者辨識分為作者意見辨識及意見持有者標記兩部分。在作者意見辨識中，本研究提出詞彙相關資訊、詞性相關資訊、具名實體資訊、標點符號資訊、文句組成資訊及意見相關資訊等特徵值並使用支援向量機來解決此問題。在意見持有者標記中，本研究提出詞彙相關資訊、詞性相關資訊、具名實體資訊、標點符號資訊、文句組成資訊、前後文相關資訊及意見相關資訊等特徵值並使用條件隨機域模型來解決此問題。最後結合作者意見辨識結果及意見持有者標記結果產生最後的意見持有者。研究所實作出來的系統，應用在NTCIR7多語意見分析評比項目繁體中文語料的評估上，可以達到F值為0.734的效能，是採取機器學習方法的參賽隊伍中效能最佳的，也相當接近目前最佳系統的效能。對於意見持有者辨識語料中標記歧異的情形，本研究加以分析，並提出使用此語料來訓練模型的方法，本研究也針對系統辨識錯誤之結果分析，並提出兩種解決方法：具名實體修復及意見持有者尾詞標記。研究將意見持有者辨識應用於意見立場分析，我們以意見持有者在不同主題中的意見傾向來代表意見立場，並以餘弦相似度代表兩個意見持有者的意見立場相似程度。我們分別使用正確答案與系統辨識出之答案做意見立場分析，雖然本系統辨識之答案的效能不是最佳的，但應用在意見立場分析上可以達到與正確答案類似的結果。People write various articles in order to express their opinions. The opinion includes opinion polarity, opinion strength, opinion target and opinion holder. In this paper, we focus on the identification of opinion holders. In each article, the opinion holder could be the post-author or a nominal (noun, noun phrase or named entity) which issues some opinions in the article. In this paper, the task of opinion holder identification is divided into two subtasks: identification of author’s opinions and labeling of opinion holders, respectively. In this paper, we apply SVM (Support Vector Machine) and CRF (Conditional random field) to automatically extract opinion holders. The SVM is adopted to identify author’s opinions, and the CRF is utilized to label opinion holders (i.e., nominals). We propose some features including lexical features, part-of-speech features, named entity features, punctuation mark features, position features, context features and opinion-word features in the SVM and the CRF. Finally, the mining process will combine the result of the SVM and CRF. In experiments, the proposed method achieves the F-score 0.734 in NTCIR7 MOAT task at traditional Chinese side. It is best than other teams who utility learning methods.誌謝 I文摘要 II文摘要 III錄 IV圖目錄 VI表目錄 VII一章 緒論 1.1 研究動機 1.2 研究目的 2.3 問題挑戰 2.4 相關研究 3.4.1 以經驗法則為基礎的相關研究 4.4.2 以機器學習為基礎的相關研究 4.4.3 本研究提出的方法 5.5 論文架構 5二章 意見持有者辨識方法 6.1 辨識流程 6.2 針對斷詞與詞性標記的特殊處理 7.3 作者意見辨識 8.3.1 特徵值擷取 9.3.2 支援向量機 10.4 意見持有者標記 11.4.1 特徵值擷取 11.4.2 決策樹演算法 14.4.3 條件隨機域模型 14.4.4 協同訓練 15.5 後置處理 16.5.1 意見持有者為詞組時之特殊處理 16.5.2 具名實體修復 17.6 合併作者意見辨識及意見持有者標記之結果 18三章 實驗與討論 20.1 實驗語料 20.1.1 NTCIR 7多語意見分析評比項目介紹 20.1.2 意見分析標記工具 21.1.3 意見持有者標記原則與答案產生方式 22.2 實驗資源 23.2.1 意見詞詞典 23.2.2 具名實體詞典 23.3 作者意見辨識實驗 24.3.1 實驗一、特徵集對作者意見辨識效能的影響 26.3.2 實驗二、訓練語料對作者意見辨識效能的影響 27.3.3 實驗三、標記歧異的語料對作者意見辨識效能的影響 29.4 意見持有者標記實驗 30.4.1 實驗一、分類演算法對意見持有者標記效能的影響 32.4.2 實驗二、特徵集對意見持有者標記效能的影響 35.4.3 實驗三、CRF標籤集對意見持有者標記效能的影響 36.4.4 實驗四、協同訓練與具名實體修復對意見持有者標記效能的影響 39.5 意見持有者辨識整體實驗 40.5.1 結果合併策略對效能的影響 40.5.2 與NTCIR 7參賽隊伍比較 41四章 意見立場分析 44.1 意見立場分析方法 44.2 意見立場分析結果 46.2.1 以所有意見持有者實體分析 46.2.2 以代表國家政府的意見持有者實體分析 47.3 意見立場分析的比較與討論 50五章 結論與未來展望 51.1 結論 51.2 未來展望 52考文獻 53錄一：意見持有者實體近義詞列表 5
Fluorescent Nanodiamond-Assisted Delivery of siRNAs
No full text發展安全且高效能的生物載體在癌症以及許多疾病的治療上面扮演至關重要的角色。以基因標靶治療為例，也就是利用設計特定基因序列的遺傳序列送入病人體內，藉由調整該基因的表現來治療相關的遺傳或後天疾病，這種治療方式已廣泛應用在許多癌症的臨床治療上面。其中短片段雙股核醣核酸干擾小體(siRNA)係藉由設計與特定基因相關的短片段雙股核醣核酸序列送入體內，抑制該基因的表現量來治療與該基因相關的疾病的方式，已被視為十分具有潛力也廣泛應用在臨床治療的重要研究領域。目前雖然有許多備受矚目的載體，但其本身的結構以及組成均可能造成對生物體的毒性，不僅如此，這些多功能的載體在生物體內長期累積可能造成免疫以及其方面的傷害，因此能夠發展新一代結合影像診斷及標靶治療於一身，最重要的是具有活體相容性的多功能奈米載體，更是生醫材料領域研究的當務之急！
螢光奈米鑽石是經由高速粒子束撞擊，再以熱能結合創造出晶格缺陷，這個真空的晶格空缺使螢光奈米鑽石在約560 nm波長的光激發之下，可以有效且穩定地放出約700 nm波長的大紅色永恆的螢光。而且，螢光奈米鑽石具有高光穩定性、完全無光漂白、且沒有blinking的獨特性質，使螢光觀察得以長期且穩定的執行。 螢光奈米鑽石不具生物毒性，而且其表面特性很容易處理成含氧的官能基，再進一步修飾得以與核酸分子或是蛋白質作結合。
本篇研究將以口腔癌細胞為基礎，系統性的研究螢光奈米鑽石與標的細胞及活體之間的生物交互作用，並找出適合的生物分子裝載條件，期望能達到最終發展口腔癌治療的依據。我們以短片段雙股核醣核酸干擾小體與螢光奈米鑽石及帶電荷聚合體結合，並且施加輕微短時間的離心作用，找到生物分子裝載最佳化之條件。並且利用奈米鑽石的螢光做為細胞追蹤工具，研究螢光奈米鑽石進入細胞並於期內所引發之交互作用。我們也同時使用冷光胜肽標定異體移植口腔癌之小鼠，了解螢光奈米鑽石結合特定雙股短片段核醣核酸在生物系統之作用效果與情形。我們的結果顯示，螢光奈米鑽石可作為極佳的生物分子載體，並證明我們可利用螢光奈米鑽石在無毒性反應下，達到更佳的基因抑制的效果。 此外我們也發現螢光奈米鑽石除了可藉由一般的細胞胞吞作用進入細胞以外，更能夠引發細胞的大胞飲作用。而離心的作用增加粒子與細胞表面接觸的頻率，因而增加活化細胞的胞吞作用，以達到更佳的基因抑制效果。我們藉由深入的探討螢光奈米鑽石與生物系統的交互作用，可望發展出可以追蹤目標細胞的核酸裝載系統，成為多功能奈米載體在癌症治療的應用上極具潛力的明日之星!Delivery technique holds the key to successful treatment of cancer and many diseases. For example, gene therapy is a promising method which manipulates the defective genes by delivery nucleotides into cells to treat inherited and acquired diseases that are currently considered incurable. It has been exercising in many clinical trials. RNA interference has been considered one of the most promising therapeutic platforms by introducing siRNA into the cell and switch off certain disease-relating genes. There are many vectors reported to be useful for genetic delivery, however, most of them have the concerns of cytotoxicities due to the component molecule and the induction of long-term damage. For these reasons, an efficient delivery system for siRNA remains to be developed.Type Ib fluorescent nanodiamonds (FNDs) can emit no photobleaching and no photoblinking fluorescence from their nitrogen-vacancy point defects, at a spectral range well suited for long term observation in living cells. They have good biocompatibility and can be easily functionalized for specific or nonspecific binding with biomolecules. In this study, based on the experiences of oral cancer, we propose to use cell and animal based oral cancer models to address the biological responses elicited by FNDs, and to simultaneously assess the best combinations of functionalization and cargo loading for future applications. We combined the FND with siRNA and common transfection reagents, applied with mild centrifugation to explore the gene-inhibition efficiency. In the same time, we studied the uptake mechanism and cellular response to the internalization of bare and cargo loaded FNDs. Besides, we tested the genetic delivery efficiency of FND-optimized siRNA complexes into xenografe bioluminescence-marked oral cancer animal models. From our results, FND showed dramatic improvement in silencing effect with good biocompatibility. And FND may be internalized into cells by macropinocytosis besides normal endocytosis pathways. We found that centrifugation facilitated the entrance of FND by increasing the contact between the particles and cellular surface, thus triggered more macropinocytosis responses to include more siRNA-combined FNDs. We provide the first and fundamental knowledge for a well-grounded development in biomedical applications of the FNDs. This is a powerful and promising achievement for subsequent improvements towards the final achievement of revolutionary new capabilities in the diagnosis, tracing and curing of cancer, as well as the treatment of other difficult diseases
Studies on the Biotransformation of Malonyl Glucosides of Isoflavone to 7-O-phosphate Conjugates by Bacillus subtilis var. natto BCRC 80517
No full textArabidopsis WRKY26 transcription factor regulates ORA47 gene expression involving in wounding signaling
No full text許多研究報導指出當植物受到傷害逆境的時候，會傳遞茉莉酸 (JA)訊息並 且誘導由 MYCs 和 ERFs 轉錄因子所調控的下游基因，進而啟動防禦機制。阿拉 伯芥 ORA47 為 AP2/ERF 轉錄因子的一員，在傷害逆境下會被誘導表現，本實驗 室前人研究中發現，ORA47 藉由辨認下游基因啟動子區域中嶄新的 cis-element (AC/GT)CGNCCA，正向調控 JA 生合成基因 LOX、AOS、AOC、OPR3、JAR1， 受傷害逆境活化的 MYC2 在傷害逆境下會辨認 ORA47 啟動子區域中的 G-box 序 列，作為 ORA47 上游正調控者，進而誘導 JA 生合成並形成正回饋路徑，在 MYC2 大量表現的轉殖株中可以偵測到被誘導表現的 ORA47 和 JA 生合成基因，然而在 myc2 knockout 突變株中，ORA47 和 JA 生合成基因表現量沒有顯著下降，所以 我們想找出其他的 ORA47 上游調控者。2008 年的文獻指出 WRKY 轉錄因子 WRKY26 具有能夠辨認 W-box-like (TTGATC)序列的能力，而我們在 ORA47 啟 動子區域中找到 4 個 W-box-like 可能的辨認位置，於是利用 EMSA 、 transactivation assay 和 ChIP 等實驗證實，WRKY26 會結合 W-box-like 4 這段 ORA47 啟動子區 域中的 DNA 序列。WRKY26 大量表現的轉殖株中，ORA47 和 JA 生合成基因在 傷害逆境下表現量都會被誘導，植株本身則有根部延長受到抑制、側根發展較促 進、生長緩慢和延遲老化等 JA 大量累積的外表型，而 wrky26 knockdown 突變株 中，ORA47 和 JA 生合成基因表現量都有些微下降，突變株的外表型則與野生型 沒有太大差異。總結本篇研究證實 WRKY26 作為 ORA47 上游正向調控因子，參 與傷害逆境誘導的 JA 訊息傳遞中，活化 JA 生合成基因表現。Jasmonates (JAs) are plant signaling molecules that play important roles in defense against insects and necrotrophic pathogens. The JA signaling pathway is relatively well studied. In our lab, Arabidopsis ORA47 was demonstrated to be the direct upstream regulator of many JA biosynthetic genes by recognizing a novel cis-element, (AC/GT)CGNCCA, in their promoters. Furthermore, MYC2 was proved to be the direct upstream regulator of ORA47 by recognizing the G-box in its promoter. Gene expression analysis shows that ORA47 and JA biosynthesis genes are all up regulated in 35S::MYC2-GFP overexpression transgenic plants, but are not down regulated in myc2 knockout mutants. Therefore, we believed that there are other transcription factors which regulate ORA47 gene expression. In this study, I confirmed that Arabidopsis WRKY26 could recognize the W-box-like cis-acting sequences, TTGATC, inthe ORA47 promoter region by EMSA, transactivation assay and ChIP assay. We suggested WRKY26 may also involve in wound-induced JA signaling via regulated ORA47 gene expression. Gene expression analysis shows that ORA47 and JA biosynthesis genes are all up regulated in 35S::WRKY26-GFP overexpression transgenic plants but down regulated in wrky26 knockdown mutants. Also, 35S::WRKY26-GFP overexpression transgenic plants show JA-related phenotype while wrky26 knockdown mutants show no difference compared with wildtype. This study reveals that WRKY26 recognizes the W-box-like cis-acting sequence in the ORA47 promoter region and is involved in wound-induced JA signaling
Binary Interaction between Typhoons Fengshen (2002) and Fungwong (2002) Based on the Potential Vorticity Diagnosis
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