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Isolation and Expression of an Eoinephrine-Synfhesizing Enzyme (PNMT) from Entamoeba Parasites

Entamoeba histolytica is a protozoan parasite known to cause infectious colitis and amoebic dysentery in humans. Its life cycle consist of two parts: the infectious cyst stage and the multiplying trophozoite stage. Epinephrine, a neurotransmitter in vertebrates, is released by the trophozoites during the process of cyst formation. The addition of epinephrine to in vitro cultures of amoebas causes them to encyst, and addition of compounds that prevent epinephrine’s activity inhibits encystations. Therefore, epinephrine plays a critical role in encystation in vitro. An understanding of the molecular intricacies of epinephrine-induced encystations may allow for pharmacological manipulation of epinephrine metabolism to control cyst formation in vitro. Drugs that either prevent cyst formation or induce it before a large amoebic population is present would result in the release of fewer cyst forms of the parasite, reducing parasite transmission from person to person. Although trophozoites release epinephrine, it is no known if E.histolytica synthesizes epinephrine or extracts it from the growth medium. Phenylethanolamine N-methyltransferase(PNMT) is the enzyme that catalyzes production of epinephrine norepinephrine. This study aims to determine the source of epinephrine by determining if E.histolytica contains a PNMT-type enzyme. PNMT amino acid sequences from several higher organisms were compared to identify conserved regions of the enzyme. These conserved amino acid sequences were then used to search for similar sequences in a database containing the recently sequenced amoeba genome. A PNMT-like gene was found in the E.histolytica database and cloned in bacteria. Yeast cells containing the cloned E.histolytica PNMT gene expressed PMT enzyme activity. This suggests that E.histolytica produces its own epinephrine, and is the most evolutionarily ancient eukaryote shown to do so. The use of inhibitors against PNMT activity is under investigation.

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由心血管超音波影像之動態分析研究主動脈硬化

我們的研究工作有兩項重要成果:首先,根據物理學的彈性體振動模型發現:主動脈硬化的定量分析訊息可由測量主動脈相對於心臟運動的延遲時間明確得知,而且可用目前臨床使用中的心臟超音波儀器直接進行此一測量。在對23 個樣品、每個樣品分析大約50至100 次心跳的初步研究中發現,此一延遲時間是確實存在的,而且延遲時間超過大約0.17秒時,樣品就可能具有動脈硬化的現象。其次,在比照過10 組樣品的數據後發現,上述之延遲時間確定可由體外的胸前超音波掃描(TTE)準確測得,而不需要採用侵入式的經食道超音波掃描(TEE),以免除受測者的不適,及避免副作用的風險,使得此一新方法更具有方便、普遍的優點。而且此一方法也可能由數據的分佈發覺心血管之其他病徵。未來仍需應用此一方法對較多樣品進行研究以進一步確定此診斷方法之可靠性。 Two important results were achieved in this research. Firstly, according to the physical model of elastic oscillation, we found that the qualitative analysis of aorta stiffness could be obtained by a measurement of the delay time of the aorta motion relative to the cardiac motion. This measurement could be carried out with the conventional echocardiography. A preliminary analysis based on 23 samples, with 50 to 100 heartbeats per sample, confirmed the existence of this delay time. Also, a delay time of greater than 0.17 sec might imply the symptom of aorta stiffness. Secondary, after a comparison of 10 samples, the aforementioned delay time could be measured with TaransThoracic Echo (TTE) instead of TransEsophadeal Echo (TEE), in which the later is invasive while the former is not. Therefore, the discomfort of the patient and the risk of invasive operation can be avoided, making this new method more convenient and more common to accomplish. This method could also clearly discern some abnormal cardiac performance. A large-scale study with this method should be conducted in the future.

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電位式茶品發酵度探針

茶品的發酵程度對其香氣與口感有決定性的影響,然而業界卻缺乏相關的客觀指標與其有效的量測方法。茶品發酵的主要化學過程是其兒茶素的氧化與聚合,這些茶單寧將隨著發酵過程逐漸由還原態轉變成氧化態。所以,不同發酵程度的茶,其氧化態單寧與還原態單寧的比將有所不同。這個比值預料可由氧化還原電位間接地量測得知。本研究使用白金絲與銀/氯化銀參考電極為電極對來量測此氧化還原電位。量具則使用具高輸入阻抗(大於十億歐姆)的pH 電極用電位計以取得茶汁中微弱的氧化還原電位訊號,可於十秒內取得高再現性(相對標準差小於3%)的電位訊號所得到的電位訊號與發酵程度呈高度的線性相關(相關係數大於0.9)。Degree of fermentation is pivotal for the aroma and the aftertaste of tea, but an objective scale and efficient evaluating methods are demanded for the important quality factor. Oxidation along with the polymerization of catechins is known to be the major chemical process during tea fermentation; the tea tannins will gradually change from their reduced forms to their oxidized formats. As the consequence, the ratio of oxidized tannins to reduced tannins will differ with the extent of fermentation. The ratio can be measured simply by the redox potential. In the present study, we used a platinum wire and an Ag/AgCl reference electrode as the electrode pair to measure the redox potential. A pH meter with high input impedance (over Giga ohm) served as our voltmeter for the weak voltage signals retrieved from tea infusions. The measurement was quick (less than 10 second) and with good reproducibility (CV0.9).

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Hourglass 2011

Over the past year Conor has been developing an electronic time keeping device named Hourglass. Hourglass has a three-fold focus on functionality, intuitive design and simplicity. To simplify the device he has limited the hardware to a bare minimum. Just three buttons and an LCD screen comprise the user-interface. Although this interface is simple, the user can access many features. These include intuitive scrolling menus, countdown, lap and alarm functions, accessed through button combinations as well as multiple ways to use single buttons, such as holding or short pressing. Many functions have been integrated into the device, such as a stopwatch with lap times, a countdown, up to 99 Custom Alarms with an individual active/inactive state and a lock/unlock feature. The stopwatch is accurate to 1 second and can be started, stopped, reset and used to record lap times. When laps have been recorded, the user can then take the time value of a lap and turn it into a countdown. A countdown of up to 99 hours can be set, and will run until deactivated or until it reaches zero. Upon reaching zero the alarm is activated. The home screen displays the time, any active countdown and notifies the user if an alarm is active. It can be locked or unlocked by holding the blue button a set period of time, helping to reduce any inadvertent change in setting. All of the functions available can be operated easily with the intuitive 3 button interface method. The menu system is simple, but has been set up through clever coding. An arrow indicated which option is selected, by pressing the top button on the clock the option above the current selection is selected/the menu scrolls up. Pressing the bottom button selects the next option in the downward direction/scrolls down. The button in the centre positioned off to the left is used to activate an option. When a Yes or No prompt appears on the screen, the action corresponds with the button position. Therefore the triangle layout of the buttons is simple and intuitive. Thus Conor’s device relies on complicated, yet elegantly formulated and annotated code and simple hardware interfaces to interact with the user in a way which is intuitive and provides great functionality. It does this while being simple and easy to understand. Here these principles are applied to a clock project, but there are implications for good design that go way beyond this context.

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利用奈米級二氧化鈦(Tio2)在不同的變因下降解膠原蛋白之研究

本實驗使用奈米級二氧化鈦能經紫外線催化,分解空氣中的水分子產生自由基,攻擊膠原蛋白中碳與氫鍵結的部份,使膠原蛋白的分子量成功的從300000 減少至少到20000 以下。其次,利用紫外線波長或酸鹼值的變因之下,控制降解出來的分子量大小。利用此法可在4個小時內得到很好的降解效果,不僅可以節省反應所需的時間,所需的成本也比當今所使用的酵素降解法來得低。 其次,我們檢測降解完後膠原蛋白的活性,發現只要不照光超過2 小時,膠原蛋白所剩的活性還不錯。如此一來,我們就可以利用此法快速的製造出有用的膠原蛋白了。 ;In the experiment, we use the properties of TiO2 which can be catalyzed by UV rays and breaking the molecules of H2O and produce free radicals that can attack the bond between carbon and oxygen in collagen, degrading collagen's molecular weight from 300000 to at least below 20000. We also use different UV rays and pH to conduct the experiment, controlling the molecular weight by degradation. By using this technique, we can get good effect of degradation in 4 hours. It can not only cut back the reaction time, but also costs much lower than the way using enzyme to degrade collagen. Furthermore, after the degradation of collagen, we also carry out the experiment to make sure whether collagen is “alive” or not. We have got the result that collagen can still work if it is not shone under UV rays more than 2 hours. In this way, we can use the technique to produce useful collagen rapidly.

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ORGANIC AND NON ORGANIC CEREALS The experimental pattern that marks the difference

1. Purpose of the research The purpose of this research is to make a suitable experimental pattern to distinguish, by scientific method, organic cereals from non organic cereals. The reference ideas consider cereals (rice, barley and maize) as a complex system that possesses its own chemical–physical properties. These cereals are able to maintain traces of the cultivation process. In non organic cereal grains foreign molecules, from synthesis substances used during their cultivation and/or in their final processing, can be found. These kinds of molecules would be absent in organic cereals. The effect of these foreign molecules traces on the principal components (glucides, proteins, lipids) of cereals is investigated by Infrared Spectroscopy (IR). 2. Procedures The spectra of a small quantity of cereal meal are recorded by the ATR (Attenuated Total Reflectance) sampling method. The meal is obtained from selected grains of rice and barley, that are grated near the germ. On the contrary, the maize grains, are cut lengthwise and the two halves are grated on the interior surface. This procedure of preparing samples, withdraws that part of the non organic cereal grains where foreign molecules are more abundant. The meal mass amounts to only a few milligrams; so in this way the dilution effect caused by starchy and proteinic parts onto the lipid part, is reduced. The cereal packaging has to be intact, well preserved and the expiry date has to be far–off. The organic packaging has the European Certification symbol and that of the authorizing agency. The cereals used in this research, have been labelled with symbols. The experimental data are processed by the NMC (Nearest Means Classification: J.Chem. Educ. 2003, 80, 542) method, adapted to cereals. 3. Data The NMC method is based on the individuation of suitable absorption bands of the IR spectrum and, for each of them, the calculation of the following quantities: the average value of the wave number (); the (Σ) value; the |diff.|=|(ῡ–)| value and the Σ|diff.| value. At the end the sum of the Σ|diff.| for all selected bands is computed in order to obtain the Σ(Σ|diff.|). Then a graph is plotted using (Σ) and Σ(Σ|diff.|) variables. The graph has a gap between the organic cereals and the non organic ones; in other words the organic cereals are found in a particular area, whilst the non organic cereals are found in another area. The boundary between the two areas is a particular value of the Σ(Σ|diff.|). This is the pattern that distinguishes organic cereals from non organic ones. 4. Conclusions For some cereals, the gap is bigger than others; but in any case the position of the cereals on one side of the boundary line or on the other, is clear. An experimental scientific pattern that marks the difference between organic cereals and non organic ones, can be useful to organic farms, authorizing agencies and consumers. This research has planned a route to find such a pattern.

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約瑟夫數列的最後一章

所謂約瑟夫問題,就是有 n 個自然數排成一環狀,從頭開始,殺 1(個數)留 1(個數),求最後留下的數會是多少?該問題在台灣的全國中小學科學展覽出現多次(如表二)。而資訊界演算法大師 Donlad E. Knuth 在其著作 The Art of Programing,CONCRETE MATHEMATICS(具體數學),針對該數列作詳細的說明;但是,不論是歷屆科學展覽或是大師著作,對於該問題,都只是談及殺 1 留β或是殺α留 1。筆者本研究中利用獨創α分類、n 及 k 分類、F 函數、b 函數及循環節,將約瑟夫問題探討範圍提升至殺α(個數)留β(個數),求倒數第 k 個留下的數是多少?

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Automatically Categorizing Commercial Segments Using Multiple Computer Vision Techniques

The purpose of Computer Vision is to understand the methods by which humans\r process visual information and likewise to create computer algorithms similar to these\r processes. Through careful observation, a computer algorithm was developed to mimic\r how humans recognize logos in television commercials. After visual analysis of\r numerous commercial sequences, it was hypothesized that the key frames (frames in\r which the logo resides) could be found using the intersection of color histograms; the\r logo region could be found using the edge density within the key frames; and the logo\r could be identified utilizing a correlation method with a database of stored logos, scaled\r to different levels using Bilinear Interpolation.\r Color histograms were implemented using one-dimensional arrays with 24 bins;\r key frames were determined by calculating the intersection between consecutive frames’\r color histograms. The edge density was calculated by convolving the key frame with\r the number of edge pixels within a 21X21 area. The identification of the logo was\r determined by computing the Sum of Square Differences between the logo region and\r the database of logos on different scales; SSD values were normalized for different\r scales.\r The algorithm was tested on 14 different sequences and determined the key frame\r with 80% accuracy. By segmenting the sequence into two key frames, the algorithm\r generated 93% accuracy. The algorithm also identified the logo region with 93%\r accuracy. The identification of the logo yielded anomalous results. These data suggest\r that motion between consecutive frames in commercial segments decreases around the\r display of the logo. They also suggest that the logo region has the most visible edges\r within the key frame.\r Future study includes a complete overhaul of the logo recognition algorithm. The\r correlation algorithm (SSD) does not work accurately enough to be used. Therefore, the\r next step is possibly to look at the edge information about the key frames. As the Canny\r algorithm determines the edges of an image, it has to determine the direction (or\r orientation) of the edges. Therefore, a proposed study includes utilizing an edge\r orientation histogram of the database of the logos and the key frames. This would mean\r that the algorithm would identify the logo in the key frames by matching edge\r orientation histograms.

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Transiency

Transiency… something which only stays for a short time, and changes\r frequently. You’re probably wondering now what this has to do with our sports and\r we must admit that at first sight it really doesn’t seem to, but think of the world an\r how many changes sports have experienced. Is it not time we thought of how sports\r facilities could be improved? And what if you were told that there would be an\r “ever-changing” sports centre which you could use?\r You really might get the chance to use such a sports centre one day, and that’s\r what our idea is all about. A multipurpose sports center is what you could call it, but\r it’s not in the least like any one you’ve seen before. In places like Hong Kong, where\r space is everything, multipurpose sports centers are common, but they always have\r so many colored clines that tend to confuse both players on the court and spectators\r off the court. Just how often have you seen referees and players arguing about\r whether the ball is out or not? And how often have you found that you are not\r enjoying the game as much as you should? Yup, we’re sure it happens all the time,\r but you don’t have to worry anymore, as our innovative design will solve all your\r problems. Yes, its time for us to change…\r In our dream sports mat, we’ll have lines which can change and also detectors to\r tell you where the balls land. You’re probably thinking, “Lines which change?”, and\r yes that’s it! The perfect solution to all those confusing lines would be lines which\r could change their positions. And to do this, we’ve made use of some new technology\r called ‘E-INK’ which would make this possible. Of course it sounds like something\r which is really costly but in fact, this technology doesn’t cost that much and its really\r durable, so it’s really worth the money to start changing. Moreover, these mats can\r also be rolled up and stored somewhere else, so when you don’t need to use the sports\r ground you can just pack it up and the venue can be used for other purposes.

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哇!好多的1、2、3!──外觀數列

「外觀數列(The Look and Say sequence)」為依照外觀產生下一列的數列,第一列為「1」,第二列則描述第一列「1 個1」而為「11」,第三列「21」,第四列「1211」,依此類推。本研究針對外觀數列的各項數學性質作研究探討,並由此推導出外觀數列的一般式,即給定第n列就可知道該列的內容。

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評估不同有機酸用於燃料電池之可行性

本研究主要著重在以三極式電化學測試探討不同有機酸燃料甲酸、草酸、檸檬酸與不同觸媒Pt/C、PtRu/C、PtPd/C 在陽極電極的氧化反應之研究。從CV 圖可得知,分子量較低的甲酸有較低的氧化電位。以CV 與LSV 圖可知,以較高的氧化電流區分,是以PtRu/C 為三種觸媒中最適合當陽極電極的;若以穩定度區分,則以PtPd/C 為最佳。我們挑選PtRu/C 此觸媒進行燃料電池放電性能測試,得到的電流不高,原因在於配置的甲酸溶液為1M,甲酸在PtRu/C 電極反應太快,質傳推動力不足,使得燃料供應不足,造成電位迅速下降。This main target of this study is using three-electrode cells to choose which Formic Acid, Oxalic Acid or Citric Acid and Pt/C, PtRu/C or PtPd/C are better for fuel cell. From CV test, Formic acid which structure is simple has the lowest oxidation potential. Combine CV with LSV, if we focus on current, PtRu/C is the best catalyst for fuel cell. But if we focus on Stability, PtPd/C has the best of them. We choose PtRu/C to do the cell performance test. The current density isn’t enough high, this is because the concentration of formic acid is just 1M. Oxidation reaction of formic acid on PtRu/C is very fast. Mass transfer driving isn’t enough for this high reaction rate, so the potential drop is very fast.

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從小玩意探討大問題-磁浮隔空旋轉器的轉動情形與磁場變化之研究

磁浮隔空旋轉器是由一個旋轉軸和底座構成,利用兩者間相互排斥的磁力, 產生隔空漂浮的效果。本研究首先對旋轉軸的結構加以分析,並設計啟動裝置, 探討啟動電壓、旋轉軸重量及底座磁力等因素對漂浮轉動的影響。 我們分析維持旋轉平衡的各種作用力,並探討旋轉軸重心位置與摩擦力的關 係,以驗證我們的分析結果。此外,我們也利用自行設計的啟動裝置,提供穩定 的初始轉速,探討旋轉軸重心位置不同時,持續轉動時間的變化,進一步驗證所 做的分析。 為了瞭解磁場在旋轉軸漂浮過程中發生的變化,我們設計了支架把空間座標 化,再以高斯計測量出各點的磁場,獲得各平面的磁場強度分佈圖。配合磁力線 分佈圖與所測得的磁場強度分佈圖,我們以一個嶄新的分析模式,將抽象的磁場 概念具體化,使我們對旋轉軸放置前後及磁力與重力平衡時的磁場變化,更深入 的了解,同時也發現磁場強度會隨距離的增加而減弱。 最後我們在旋轉器上裝置感應線圈,經由旋轉實驗測得感應電壓的存在,證 明旋轉器轉動時,磁場會產生變化。 經由對磁浮隔空旋轉器的探討,我們得以了解它的漂浮原理、磁力與摩擦力 間的平衡關係,以及旋轉前後磁場變化。The Magnetic Floating Spinner(MFS) is composed of one spinner with a magnetic base. The floating effect of the spinner is caused by the interaction between the two opposite magnetic fields. We first analyzed the detail structure of the MFS, and then designed a starter to rotate it. Later, we studied the effect of starting electric potential, the weight of the spinner and the magnetic force of the base on the floating movement. We presented an explanation for the forces that maintained the floating of the spinner and, to support that, we studied the friction force with the position change of the spinner gravity centre. We also used the starter designed by us to provide a stable initial rotating force and analyzed the relationship between the change of gravity centre position and the duration of rotation. In order to understand the magnetic field change during floating movement, we designed a spatial frame to coordinate the spinner that floated above the base. We measured the surrounding magnetic force with the Goth’s apparatus and conducted a magnetic force distribution diagram. According to this diagram and the line of magnetic force, we therefore provide a brand new analysis model , which bring the abstract concepts of the magnetic field into a concrete theory. This research not only brings us to understand the magnetic field change of the spinner before and after its placement over the base and the balance between the magnetic and the gravity force, but also reveals that the magnetic force will wane with the increase of distance. Finally, we placed an induction coil by the spinner to detect a voltage change during spinner movement. This is an evidence that the magnetic field will change during the spinner movement. Through the study of MFS, we can now understand why it floats, the balance between magnetic and friction force, and the change of the magnetic force before and after the spinner movement. MFS = Magnetic Floating Spinner

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