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本研究的目的在於探討蜻蜓兩對翅膀在不同的相位差之下對升力有什麼影響。在觀察蜻蜓及察閱相關網站、研究後發現蜻蜓前後翅的相為差有相差0.5 週期、相差0.25 週期、同週期三種不同振翅方式。在界定欲實驗的種類和評估現有的能力及資源後,決定研究加上相差為0.125 週期的四種振翅方式,於無風條件、相同的振翅頻率下進行實驗,測量其升力的變化週期。測量結果參照前人的文獻後發現,0.5週期產生的升力雖最小,但最平穩,所以為蜻蜓最常用的飛行方式。而0.25 週期升力會疊加,往下的力被抵銷,故為向上加速時使用。 ;The purpose of this study is to investigate the phase-shift between the front-pair and rear-pair wings on the maximum lift of a dragonfly. As observing the flight of a dragonfly and the literature survey from web sides, it has been observed that the general phase-shift modes of the dragonfly are in-phase-shift, 1/2 period and 1/4 period. It has been decided to include a 1/8 period phase-shift mode into the known three modes under the no wind condition with a fixed flapping frequency, the cyclic lift force of the dragonfly wing model has been measured. When it is flapping, we put the model on an electronic scale for measuring the weight of the model. After that we minus the original weight of the model, knowing the increasing or decreasing weight and the extra weight is the lift force. The results show that 1/2 period phase-shift mode produces the least lift force; however, it is the most stable flight, and is being adopted by the dragonfly for level flight. The in-phase-shift mode can produce more lift force on the flapping processes. The 1/4 period phase-shift mode produce the most acceleration, being adopted by the dragonfly for the climb flight.
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微孔珊瑚是優良的生物氣候記錄器,可準確記錄海水表面水溫、陸源沉積物通量和其他微量海水組成等,已成為熱帶氣候變遷研究的重要工具。然而,珊瑚成長速率則顯著受限於海水表溫影響(邱景星,1999)。太陽是地表能量最主要來源,其活動狀態能深遠掌控地球氣候變化,因此其週期性變動規律,已成為近期地球科學家探討環境變遷的重要資訊。 本研究以台灣東南外海綠島採集的微孔珊瑚骨骼樣本,藉由X-ray精確測量其年平均生長速率及觀察骨骼內微量腐殖酸螢光特性,並透過比對太陽輻射量、珊瑚生長與太陽黑子數目的相關性分析,以推倒百年來控制地表氣候變遷的主要因素。 本研究經由頻譜分析、主變量計算、平均標準差和太陽輻射角修正,獲得正確太陽黑子數目、地區性輻射、海水表面溫度和珊瑚生長速率等資料,並討論其間的相互關係。 結果顯示,太陽輻射、海水表面溫度和氣溫有高度正相關(r2>0.62),證實太陽對地球氣候系統的重要性。太陽黑子與輻射資料,則因大氣折射、日照時數等因素影響,正設法解決這些干擾效應;而珊瑚生長速率與海水表面溫度的相關性,則涉及雙極化效應(註)及其他未知因素影響,尚待進一步釐清。 (註):雙極化效應指珊瑚在過高或過低的環境下,生長速率皆會停止 The skeleton of Porites corals is one of the most useful biogenic recorders, which provide relevant information of abrupt climate change, such as sea surface temperatures (SSTs), riverine sedimentary flux, and seawater compositional variations. Information retrieved from coral skeleton, therefore, has become a powerful tool for studying tropical climate change. The annual growth rate of Porites corals, however, was affected strongly by local SSTs (Chiu, 1999). On the other hand, the climatic condition on Earth surface is regulated significantly by solar activity. Subsequently any intensity or periodicity variation in sunspot activity will cause major global environmental changes. This research aims to study coral skeleton collected from the Orchid Island (Lan-yu) offshore southeastern Taiwan for precise measurement of annual growth rate using X-ray density bands, as well as the luminous characteristics of trace humic acids in skeleton. A systematic comparison among solar irradiation, SSTs and coral growth rate will provide critical information on major factors that may affect environmental changes occurred during the last millennium. In this study, we apply spectrum analyses, principal component, mean standard error method, and modified sun irradiation angle to correct biases presented in the available data of observed sunspot number, local irradiation, SSTs and coral annual growth rate and to examine possible relationships among these factors. We have found excellent correlation coefficient (r2>0.62) in solar irradiation, SSTs and air-temperature, which support the importance of solar irradiation to the earth surface climate. However, effects on cloud and length of sun irradiation need further investigation to emphasize the importance of sunspot activity to the annual growth rate of Porites corals. No straight forward relationships were observed between coral growth rate and local SSTs due to complicated biological effect (1*) or other unknown factors, waits for further investigation in the near future. 1* Complicated biological effect means that coral may stop growing their skeletons when the temperature it lives in is over range for growth.
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Synthetic Analogs of Smoothened Intracellular Loop as Potent Inhibitors of Cancer Cells Growth
Smoothened (SMO) is a critical component of Hedgehog (HH) pathway that is essential for stem cell renewal and is dysregulated in many cancer types. SMO is a seven transmembrane domain protein with three intracellular loops. Primary structures of SMO intracellular loops are unique and very much conserved among the species, which is indicative of significant and unique roles in intermolecular or intramolecular interactions. The hypothesis was that synthetic analogs of SMO intracellular loops may function as HH pathway inhibitors. Derivatives of second intracellular loop were synthesized utilizing automated solid phase peptide synthesis based on Fmoc chemistry. Peptides were purified by HPLC and there anti-proliferative activity tested on melanoma cells by MTT assay. Targeted libraries of second loop derivatives of varying length helped to identify compounds that inhibited the growth of melanoma cells in vitro with IC50 in nanomolar range. The most potent of antagonists obtained is the palmitoyl derivative of the Nterminal half of the loop, and is 12 residues long. Lipidation proved to be critical for the activity. Remarkably, retro-inverso versions of the peptide, in which all amino acids are in D-configuration, are even more potent and have IC50 in subnanomolar range. Circular dichroism studies proved that the peptides are folded both in aqueous solutions and in the presence of lipids mimicking the membrane environment. They also suggested that retroinverso analogs have a different fold, which may contribute to higher activity. The new compounds are promising drug candidates and present convenient tools for solving the\r mechanisms of hedgehog signaling.
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YWHAZ(14-3-3ζ)蛋白在肺腺癌細胞中可能活化Wnt路徑之探討
YWHAZ(14-3-3δ)蛋白被證實在肺腺癌中會引發上皮-間葉的轉變作用(epithelial - mesenchymal transition ; EMT)導致癌轉移,然而其分子機制卻不清楚。先前實驗室利用cDNA微陣列技術(microarray)發現肺腺癌細胞大量表現YWHAZ蛋白會導致Wnt訊息傳遞路徑之相關基因大量表現。因此,本研究目的是探討YWHAZ蛋白在肺腺癌細胞中是否會活化Wnt途徑而引發EMT。\r 本研究結果發現大量表現YWHAZ蛋白除了會增加細胞質中β-catenin的表現量,也會增加細胞核內 β-catenin 和TCF4 的蛋白表現量,並且在細胞核中與β-catenin和TCF4形成複合體;而臨床肺腺癌病患檢體中發現,相較於正常肺葉組織,YWHAZ蛋白與β-catenin在肺癌組織的檢體有較高的表現量,同時少部分會進入細胞核內。經由以上結果,我們推測YWHAZ蛋白可能會結合β-catenin與TCF4蛋白並活化Wnt途徑,因而引發EMT之產生,而促進肺癌轉移。說明YHWAZ蛋白有潛力成為日後診斷肺腺癌的指標蛋白(marker protein),同時亦成為治療肺腺癌的標的蛋白(target protein)。\r 重要性\r 1.提出YWHAZ可能在肺腺癌細胞中活化Wnt訊息傳遞路徑(Wnt signaling pathway)而導致癌轉移。\r 2.再度指出YWHAZ在腫瘤生物學的重要性。\r 3.對於肺腺癌轉移提供了臨床診斷及治療的另一種選擇 ─ YWHAZ。
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以阻抗匹配調整太陽能最大功率輸出之研究
In recent years, the price of the oil keeps rising continuously. As a result, the prices of the commodities are rising, too. But what does this mean? This situation stands for the resources on are becoming more and more valuable. A few months ago, I read a Weekly Business Magazine and a Scientist Magazine. They both pointed out that the resources such as oil would disappear after fifty years, and that was a horrible phenomenon. Since almost everything in our modern lives are related to oil, like automobile, motorcycle and air plane. They all need oil for its ingredient. Even plastic bag plays a part in the products of it. I really cannot imagine what it would be like if we don’t have oil after fifty years. Owing to the green house effect is becoming more severe, there are many substitution resources found, such as hydraulic power, wind power and solar energy…etc. What we’re discussing in our topic is how to enhance the power of solar energy, because for now, we all know that the solar module is very expensive and it cost a great deal of money just only one square meter, but the price of module converted from sunlight or heat energy can’t be higher. Therefore, the work is mainly to design and carry out a solar max power point track. 近年來,油價不斷的上漲,連帶著民生的物價漲幅也是越來越可觀,但…這意味著什麼 呢??這所代表的是地球上的資源可以說是越來越珍貴了,前陣子曾經看過商業週刊、科學人 雜誌…他們紛紛所指石油這種能源可能在五十年後就消失殆盡,這個可是非常可怕的結果。 鑑於溫室效應愈趨嚴重,許多的替代能源紛紛出籠,像是風力、水力和太陽能等等。我們這 次的主題是在討論如何提高太陽能效率,現在的太陽能模組我們都曉得非常的昂貴,但是由 太陽轉化成電能的效率卻是低的可以。所以本作品主要目的在於設計與實現一個太陽能最大 功率追蹤器。
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Recovering bioethanol from fruit wastes
1. Purpose of the research: Recovering bioethanol from fruit wastes by using brewing yeast and enzyme Viscozyme L\r 2. Procedures: Four different experiments were conducted in our project.\r Experiment-1: Samples in RM by the addition of only S.Cerevisia.\r Experiment-2: Samples in RM broth meduim by the addtion of 100 μl/g ViscozymeL and S. Cerevisiae\r Experiment-3 : ViscozymeL with different concentration\r Experiment-4: to determenine whether the enzyme with high concentration inhibited the fermentation.\r Analysis of ethanol: HPLC method was used for the analysis;\r HPLC method: (high performance liquid chromatography)\r 3. Data\r HPLC measured initial and final concentrations of glucose and ethanol by the addtion of S. Cerevisiae.\r Initial glucose concentration and final ethanol concentration was the highest in Grape pulp 12 and 9 g/L respectively. Despite the glucose concentration was the lowest, the ethanol concentration was quite high (7 g/L) in the mixture with orange. The lowest ethanol was produced in the mixture with pomegranate.\r Concentrations of ethanol and glucose from the samples in RM broth meduim by the addtion of 100 μl/g ViscozymeL and S. Cerevisiae\r After the 24 hour incubation by the addition of enzyme glucose concentration incresed by 1, 4 and 2 respectively in sample 1, 2 and 3. The ethanol concentrations in comparison to first experiment were higher especially in the sample1 (grape pulp).\r Effect of ViscozymeL with different concentration on glucose production.\r The glucose concentration generally increased by the addition of 200 micro L of enzyme as the time proceeded. In grape pulp sample glucose concentartion didnt increased by the addition of 500 micro L enzyme.\r The remaning glucose and produced ethanol concentrations by the addition of viscozyme L with two different concentartion and S. Cerevisiae\r As the concentartion of enzyme added incresed the amout of ethanol also inreased in sample 2 and 3 but in the sample 3 the fermentation was inhibited.\r 4. Conclusions\r In this study sugars in fruit wastes that are regularly not recylecled were fermented successfully into ethanol by using S. Cerevisiae.\r Generally we get more ethanol from the samples when the enzyme was used. As the graph5 shows the ethanol concentration generally increased as the enzyme concentration increased. But especially in the sample1 (mixture with pomegranate) at 200 and 500 micro liter concentrations, ethanol production were 2 and 0 g/L respectively. In the light of this daha we conluded that the enzyme with high concentartion might inhibit the fermentation. When the activity of enzyme was inhibited by keeping the pretreated enzyme in boiling water, the fermentation restarted and recovered more ethanol; 8 and 12 g/L at the enzyme concentration of 200 and 500 microliter respectively.
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Few plants can grow in the place where Wedelia trilobata grows. In the following experiment, the leaves ans stalks(of the plants from Wedelia trilobata) are extracted for experimental purpose .The data and records of the experiment have shown that Wedelia trilo ata indeed refain the growth of plants such as mung bean, teeding seed, yeast’s respiration and the photosynthesis. We use the function of dieing the polyphenols to know that the Wedelia trilobata can produce Allelochemicals called as the polyphemols The mesophycell produce the polyphemols from chloroplast of cortex,the polyphemols transport to root and release from root exudation. The plant will absorb polyphemols of the soil, and will affect the growth of the plant. If we can separate and purify the Allelochemicals, we can make it as natural herbicideb. 南美蟛蜞菊所在之處,少有其他植物,本實驗採南美蟛蜞菊植栽區之土壤與南美蟛蜞菊莖或葉之萃取液進行相剋作用之研究,結果顯示南美蟛蜞菊確實會抑制小麥與綠豆種子萌發及幼苗生長,並抑制酵母菌的呼吸作用及植物光合作用中之光反應。 利用多酚類染色方法得知南美蟛蜞菊產生的相剋化合物為多酚類,且該多酚類由葉肉細胞與莖內皮層中具葉綠體之細胞產生,經韌皮部輸送至根,再由根經泌濾作用釋出。土壤中的多酚類會被植物吸收,進而影響植物的生長與發育。 若能將該相剋化合物---多酚類分離與純化,或可作為具選擇性之天然除草劑。
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The objective of this project is to investigate styrene butadiene rubber(SBR), which is the most important synthetic rubber. The project contains production methods, properties, safety methods and applications for emulsion SBR. The goal is to determine which production technique of SBR is the most beneficial. This is based on the chemical and physical properties of the final product and its quality. The process that is used in the project is emulsion SBR with combined coagulation stripping. The rubber production plant is a profitable venture. The total capital cost is estimated around $31,361,572, with an annual production cost of about $67,281,378 yearly, generating revenues of $73,801,760 per fiscal year, with an interest rate of 5%. The life of the plant is 15 years and would produce 50,000 ton/year.
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口蹄疫病毒鞘蛋白rVP1 誘發Prohibitin 之遷移
細胞凋亡具有控制生物體細胞數目之功能,能讓特定的細胞走向死亡,因此若能掌握其作用機制,便可能藉由調控細胞凋亡的發生,進而應用於癌症治療。前人研究(2.)指出,經基因重組技術純化之口蹄疫病毒鞘蛋白rVP1,會導致BHK-21的Akt 蛋白質去活化,引起細胞凋亡的現象。然而在其後續的研究中,卻發現到在BHK-21中大量表現磷酸化的Akt 蛋白質,並無法反轉由rVP1 所誘發之細胞凋亡。因此本實驗利用二維蛋白質電泳,尋找Akt pathway 以外之細胞凋亡相關蛋白質。目前已證明Prohibitin 此一蛋白質,在由rVP1 所引起之細胞凋亡中,有自細胞核移動至細胞質的現象。此外,亦經由實驗排除Prohibitin 位於Akt pathway 的可能性。Western Blot 之結果更顯示,經rVP1 處理後,Prohibitin 在很短的時間內便出現遷移的現象,故推測其具有調控細胞凋亡上游反應的功能。Apoptosis can lead some specific cells to programmed death, thus, it is a major way for creatures to control their cells amounts. If we can command the mechanism of apoptosis, we may use it as a therapy for cancer by artificial regulation of apoptosis. VP1 is one of the capsid proteins of Foot and Mouth Disease Virus (FMDV). A research (2.) has indicated that the recombinant VP1 (rVP1) can result in dephosphorylation of Akt in BHK-21, and then lead the cells to apoptosis. However, in their follow-up experiments, they discovered that even if they expressed great amount of phospho-Akt in BHK-21, it still couldn’t reverse the apoptosis induced by rVP1. Therefore, this experiment takes the advantage of two-dimension protein electrophoresis (2D) in order to find apoptotic proteins excluded from the Akt pathway. I have found that Prohibitin exports from nucleus to cytosol after rVP1 treatment. Furthermore, I eliminate the possibility that Prohibitin’s may be located in Akt pathway. The results of Western Blot also shows that protein amount of Prohibitin in BHK-21 increase after rVP1 treatment, hence the purpose of nuclear export of Prohibitin might not be to degrade it. It might have some much more important function in the process of exportation. Besides, Prohibitin exports to cytosol in quite a short time after rVP1 treatment. According to this phenomenon, I suppose that Prohibitin has a role as a regulator of apoptotic up-stream reactions.
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鹼性電池使用的電解液均為強鹼,電池中的鋅極會與其發生腐蝕反應,使得電池放電壽命降低,並產生氫氣,而大量氫氣使得電池有爆裂的危險,為了改善上述問題,我們自行設計了氣體觀測儀器,用來檢測銀鋅電池充放電與靜置時之氣體產生量,更藉由探討影響變因的過程找出銀鋅電池較合適之使用條件,其中包含電解液種類及濃度之選擇、電極面積與充電電流對使用效果之影響,並改善電池腐蝕程度;我們將鋅極以浸鍍處理(Sn:Pb =1:1 )並搭配電解液添加物(KOH:Zn(OH)42 -= 2:1) 可效率地抑制氣體產生;更用氯化銀粉末取代傳統氧化銀極片為正極,發現氯化銀可代替氧化銀電極,且有不錯的放電效果。;As we know, the electrolyte solution used in an alkalinebattery is a concentrated alkaline solution, which corrodes the zinc electrode in a battery of this kind. The corrosive reaction not only reduces the lifespan of the battery but also produces hydrogen, causing the battery to explode. This study is intended to help us design a device to measure the quantity of hydrogen gas generated in the charging of a zinc-silver battery. We have studied several factors affecting zinc-silver battery, including the variety of electrolyte, the concentration of alkaline solution, the surface of electrode, and the density of charging current, etc. To reduce the corrosion of zinc electrode, we plate the zinc electrode by the immersion electroless plating method, using several kinds of low-polluting anti-corrosive additives (metallic compounds such as lead and tin). We also add zincate ion into electrolyte solution to further reduce the quantity of hydrogen produced. The experiments show a zinc-silver alkaline battery works most efficiently, if the powder of silver chloride is used instead of silver oxide.
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Synthesis and Characterization of Starch-Nanosized Calcium Phosphate Composites
Nano-sized calcium phosphate was used in the synthesis of starch-based composite plastics to provide a cheap but sturdier biodegradable alternative to petroleum derived plastics used in film packaging. Nano-sized calcium phosphates were produced from the precipitation reaction of calcium nitrate tetrahydrate (Ca(NO3)2 ‧ 4H2O) and phosphoric acid (H3PO4). The nanoparticles were co-extruded and molded with thermoplastic starch (TPS) at ratios of 0%, 1%, and 5% by mass. Tensile strength and elongation percentage of the resultant composite plastics were tested in three replicates. The results show that there is a significant difference between the tensile strengths of the 0% and 5% calcium phosphate composites at a 5% level of significance. The trend between the composite’s tensile strength and percentage calcium phosphate follows a geometric progression, enabling a projection for the 10% nano-calcium phosphate to have a tensile strength of 10 MPa, the average tensile strength for low-density polyethylene (LDPE). This shows that it is feasible to synthesize a 10% nano-calcium phosphate-TPS plastic that can be a viable substitute for LDPE plastics in film packaging, paving the way for the commercialization of starch-based plastics. The use of biodegradable plastics with improved physical characteristics will lessen consumer dependence on petroleum derived plastics and solve the environmental issues brought about by the use of such plastics.
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想像一下,原來固定的一個黑色大正方形(以下我們簡稱S1)四個角經過較小之正方形(以下簡稱S2)遮蓋後旋轉,為什麼會有放大縮小的感覺呢?(圖一)
我們猜測這是因為未被遮蓋部分(以下簡稱S3)的面積改變了,所造成的結果。令S1的邊長為 r,S2的一個小正方形邊長為n,k=r-n,θ為旋轉角度,我們實際算出了旋轉角度θ對S3的面積函數,
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