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熱門關鍵字: the king 水果 豆漿 電腦
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Asymmetric Total Synthesis of GlaxoSmithKline’s Potent Phosphodiesterase PDE IVb Inhibitor

Phosphodiestarase of subtype PDE IVb inhibitors are considered as perspective drugs for the treatment of the central nervous system disorders (depression, Alzheimer’s disease, Parkinson’s disease). Pyrrolizidinone Glaxo-1, proposed by GlaxoSmithKline, is a highly potent PDE IVb inhibitor (IC50 = 63 nM), then conventional phosphodiesterase inhibitors Ro-20-1724, Rolipram and Cilomilast. However the activity of the Glaxo-1 was studied on a racemic sample, since the asymmetric approach to its synthesis has not been developed. Therefore the purpose of this research was the development of an efficient synthetic scheme enabling enantioselective excess to both (-)- and (+)-Glaxo-1, which can be than subjected to biological studies. \r The key stage in proposed asymmetric synthesis (-)- and (+)-Glaxo-1 is stereoselective [4+2]-cycloaddition of the nitroolefin to an optically activity vinyl ethers, derived from (-)- or (+)-trans-2-phenylcyclohexanols. The resulting chiral cyclic nitronates are transformed into a functionalized cyclic oxime ethers using tandem sylilation-nucleophilic substitution procedure. Reduction and decarboxylation of these products lead to optically pure Glaxo-1 and the regeneration of chiral 2-phenylcyclohexanols (91%). \r Thus both enantiomers (+) and (-)-Glaxo-1 were obtained selectively in average yield 12% from isovaniline and nitroethane. The study of biological profiles of each enantiomer of Glaxo-1 will be conducted in near future.

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Vitamin C in Cold and Flu Drinks

This chemistry project was designed to measure the vitamin C levels within liquid cold and flu remedies, and see if they had been accurately stated on the package. A range of Cold and flu drinks was selected, including one made with only cold water (Lemsip Original, Lemsip Max, Effer-C-Cold Water, Relief and Lemting) .The procedure used to carry out the experiment was a redox titration, each trial required two titrations, with the first being a blank titration to determine a sodium thiosulfate concentration in the absence of vitamin C. The following Drinks had more Vitamin C than stated on the packaging – Lemsip Original (19.4%), Lemsip Max (22.1%), Effer-C (17%) and Relief (8.8%). Lemting was the only drink made to directions that had less Vitamin C than stated by 31.8%. Two conclusions can be drawn from these results, the first being that Lemting has the most inaccurately recorded mass of vitamin C and is also the only drink with less vitamin C than stated. The other interesting result is that Effer-C (the only drink made with cold water) had 170mg of extra vitamin C. Of the other drinks that had more vitamin C, Lemsip Max was next with an extra 22.8mg. Early research had showed that Vitamin C was affected by high temperatures (above approximately 70oC) and, as cold and flu drinks are commonly made with hot water the Vitamin C levels might change when they were made up. This poses a further possible research question which is, in making cold and flu remedies with hot water is some of the available Vitamin C being destroyed?

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The Use of Simulated Annealing in Predicting Solar Flare Activity

A program based on the simulated annealing (SA) algorithm was developed to allow for a longer-term prediction of the occurrence of solar flares, thus reducing the risks they may pose to astronauts, satellites, and ultimately the planet Earth. Sunspot data such as the solar cycle, the appearance of sunspots, the sun's magnetic field, the occurrence of solar flares and other factors that concern the sun were considered in the development of the algorithm. The program, coded in C++, included providing for an initial random state that pertained to the sun's state at a specified time. A neighborhood function was designed based on how sunspots are formed and how they disappear, and the probability function was designed using previous solar cycles to show relationships between the number of sunspots and the time it takes for the sun to reach solar maxima. Finally, the cooling function was designed as a representation of the time. Recorded sunspot counts obtained from the US National Geophysical Data Center (NGDC) during the solar cycle 22 from 1986 to 1996 was used as test data. The output was compared to the actual recorded solar events or the period. The program was found to be 66.7% accurate in predicting solar flares when compared on a smoothed trendline, while it exhibited a 50.5% accuracy when comparing day-to-day data. Since solar flare acitivty is predicted in terms of the trend of activity and intensity, improving daily data accuracy is superfluous. Smoothed trendline prediction accuracy may however be improved by altering the importance of each factor in predicting solar flare activity and by devising a different sunspot classification scheme for intensity and activity.

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The Flying Chloroplasts Drug Test

Previously, I studied the acute effects of a common broadleaf herbicide, Killex (by Montsano) and a pesticide, Spidercide (by Wilson), on cytoplasmic streaming in detached leaves from the pond weed, Elodea canadensis. I found that Killex, active ingredient 2-4D, an auxin analog, applied at the recommended dose decreased the rate of cytoplasmic streaming by 64% over a 20 minute observational period. The Spidercide, active ingredient d-trans allethrin, a Na+ channel activator, stopped cytoplasmic streaming after a 5 minute exposure and no recovery was observed during the 20 minute observational period.

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直角三角形生成關係的研究與發展

k(2αβ ,α2 ? β2,α2 + β2 )是大家熟悉畢氏定理的通式解,且一般書籍的証明大都採用代數的手法證明。以國中生而言,上述的代數方對國中生來說不夠直接且較無推展的實用性。因此幾何觀點出發發展另一種思考方式,利用角平線的性質給予畢氏定理比例解另一種全新的詮釋,並賦予比例解中的參數α 、β 在幾何的意義。在推理的過程中,我們得到一個相當有用的對應關係:一個有理數對應到一個直角三角形、兩個有理數對應到海倫三角形,再將此對應關係運用到各種幾何圖形上面,即可證明出他們所對應的通式解。最後我的興趣鎖定在海倫三角形、完美海倫多邊形與超完美海倫多邊形上的做圖方法上,善用我們所發展的對應關係,上述的問題皆可迎刃而解。k(2αβ ,α2 ? β2,α2 + β2 ) is a popular formula in Pythagoras Theory, often proved in algebra approach among books. Nevertheless, in light of junior high students, the aforementioned algebra method is neither direct nor practical. Hence, a different thinking method is derived from geometry perspective, using the straight line concept to reinterpret Pythagoras Theory and define the geometric meanings of α andβ . In the process of logical development, a useful correlation emerges: a rational number correlates with a straight-angled triangle, and two rational numbers correlate with Heron Triangle. This correlation can be applied to all kinds of geometrical diagrams to prove the correlated homogenous solution. Ultimately, my interest lies in the diagram methods of Heron Triangle, Perfect Heron Polygon, and Super Perfect Heron Polygon in order to apply our developed correlations to solve the above mentioned problems.

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Tree'ting Wood Better:Sunscreen for Trees

The purpose of this experiment is to determine whether or not wood can be used as an alternative testing method for sunscreens and which species of wood are good for this objective. This will be accomplished by applying varying strengths, or SPFs, of sunscreens onto thin wood veneers. They will then be exposed using a weatherometer, in which real light and sun conditions will be simulated. Using a device called a Pulmac, the samples of wood will be pulled apart from the centre at zero span. Based on the consistency of the strengths, it can be determined how the wood reacts to the sunscreen and whether that species of wood is suitable as a testing medium. Trees are an important commodity which enrich the lives of many people, particularly those who live in British Columbia. They provide the means of living and recreation for numerous people, whether it is employment, business, housing, or camping. Since trees are a renewable resource, they are convenient and realistic to use for testing. There are two possible extensions to this project. If the active ingredients in sunscreens can be determined, then we may be able to use these elements to create a new type of stain for fences and other structures. This could make the necessity for painting less frequent, creating cheaper options for the homeowner. The second possible extension of this project is to use the results to as an initiative to reduce the amount of animal and human testing done by manufacturers. This is important, as animal testing not only causes unnecessary pain, but often the results are not very accurate. Overall, I determined that this method of testing sunscreens would work quite well, especially with the following species, listed in decreasing order. 1) Yellow Cedar 2) Yellow Poplar 3) Maple 4) Hemlock These results were based on how tightly grouped together the means of the strength values were for each species. The closer they were, the more consistent that type of wood and therefore the better they are for testing. Overall, I think this method of testing sunscreens would work quite well, particularly with the yellow cedar, maple, yellow poplar and hemlock, as they resulted in fairly consistent strength values. Generally, the sunscreens with a high SPF, or Sun Protection Factor, resulted in a lower strength loss than the sunscreen with SPF 15. In addition to proving that sunscreen is a good method for preventing UV rays from reaching the skin, this experiment has also confirmed that there are other methods of testing sunscreens, which can be researched further. Along with my main presentation I will be showing various graphs, statistics, and pictures. They will be supplemented by a booklet of “Commonly Asked Questions and Answers” and species descriptions for each type of wood.

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The Titanium Dioxide Toilet Disinfectant

This project aims to improve the quality of toilet hygiene. The product designed should fulfill the requirements of being an environmentally friendly, user friendly and economical toilet seat system which guarantees the safety and hygiene of the toilet. This project also aims to discover the efficiency of the toilet seat system in eliminating pathogens through conducting various experiments.\r In this project, the photocatalytic property of titanium dioxide is applied. When titanium dioxide is under exposure to ultraviolet radiation, they generate free radicals, which are efficient oxidizers of organic substances. Also, research has shown that the safest ultraviolet light used will be UVA. Thus, by using titanium dioxide paint under exposure to ultraviolet light to oxidize pathogens and toxins, the aims will be achieved. Other than that, experiments will be conducted to explore the efficiency of titanium dioxide under exposure to UV radiation in eliminating pathogens by counting the number of bacteria on the toilet seat system after different time intervals the seat system has been turned on.\r The procedure of constructing the product includes drafting the product, purchasing the appropriate apparatus and materials, constructing the prototype, and checking if the product fits the goals set. Lastly, improving the design based on the flaws found during the checking procedure, as well as checking the product to see if it fits the original goals set.\r The procedure of the experiments aimed to explore the efficiency of titanium dioxide under exposure to UV radiation in eliminating pathogens conducted includes\r counting the number of bacteria on the toilet seat system after different time intervals by inoculation of bacteria on the agar plates.\r Test results showed that the number of bacteria had a steady and notable decline after different time intervals. Results also showed that bacteria would be thoroughly terminated after the system had been turned on for at most one hour. The information was then used to set the delay timer to restrict the amount of time the ultraviolet lamp was turned on to save energy.\r Moreover, the toilet seat system has also been improved so that it will complete the automatic cleaning procedure even without the user lowering the toilet seat. This improvement was made so that the product could be more convenient to toilet users.\r The system also deodorizes the toilet as the oxidization of bacteria and organic substances reduces the putrid odor released by them when they carry out chemical reactions.\r In conclusion, the project succeeds in accomplishing the goals set and is capable of improving the quality of toilet hygiene, especially in common households. The project is also successful in finding out that the toilet seat system is efficient in eliminating pathogens.

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應用垂直循環層流淨化水質之研究

The results of the thermal diffusion experimental show that the separation efficient\r increases with increasing ΔT, but decreases with increasing Q at C0 constant. When\r Q is kept constant, the efficient of change ΔT are small, and the maximum at C0 about\r 545 mg/L. The purification efficient of raw water for thermal diffusion is low.\r And it is high energy consumption, difficult operation, and high costs. So the potential\r of the application is low. Therefore, the vertical circulatory laminar flow apparatus\r was developed in this study. And the separation equation of this apparatus was also\r set up. The results of vertical circulatory laminar flow experimental show that\r the efficient increase with increasing V, and the optimum conditions are at about\r Q= 1.05 L/min, C0=800±50 mg/L, and V=26 cm/min. The separation efficient of the\r vertical circulatory laminar flow apparatus is higher than thermal diffusion apparatus.\r And its energy consumption and costs are low, and easy to operate. Since all interior\r moveable plates have two operation sides, so the multiple channel apparatus is application.\r Therefore, the multiple channel apparatus can treat large amount raw water and has\r low costs. The efficient of the experimental all are better than the theoretical\r values that may due to: (1)the assumed partical diameter is too small,(2)the flow\r is not real laminar flow, and (3)the end-side effect is not considerate. \r 熱擴散實驗結果顯示在固定C0下,分離成效隨ΔT增加而增高,但隨進料流率增加而降低。在固定ΔT下,分離效率亦隨進料流率增加而降低。固定進料流率下,增加ΔT對分離效果的影響不大,以C0=545±10\r mg/L時,顯現出最佳成效。採用熱擴散裝置雖對降低原水中之懸浮微粒含量效果有限,且能源需求高,造成高成本和操作複雜,不具實用潛力。為提高分離原水微粒之成率,以及簡化操作與降低成本,本研究開發垂直旋轉帶裝置來製造出上下循環水流,並導出水流與微粒於其中之流速分布式,以及頂部、底部出口之微粒濃度計算式。垂直循環轉帶實驗結果,顯示提高V值有助於降低Ct/Cb比值;Q=\r 1.05 L/min左右、C0=800±50 mg/L下與V在26 cm/min左右,均有較低之Ct/Cb比值。垂直旋轉帶裝置分離成效明顯優於熱擴散裝置,且設備簡單、能源需求低與操作容易。由於旋轉帶之兩面均可以做為移動平板,因此不僅可以用來處理大量之高濁度原水,也能更具經濟效益。由理論與實驗結果之比較,顯示理論成效較實驗差,探討其原因可能是:(1)平均粒徑之假設值偏低、(2)流場並非全然以層流流動、(3)兩端終端效應未加考慮等。

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Mechanisms of Tumor Cell Invasion: The Role of Stat3 in Squamous Cell Carcinoma

Skin cancer, including basal cell and squamous cell skin carcinoma, is known to\r be the most common cancer type. Skin cancer is thought to make up half of all known\r cancers. Over one million non-melanoma skin cancers (NMSC) are reported every year. \r Approximately 300,000 of these cases are squamous cell carcinoma (SCC). It is\r estimated that about 2,000 people die from NMSC each year. Of the two skin cancer\r types, SCC tends to be the more clinically aggressive and likely to spread and invade,\r typically by way of blood or lymphatic vessels. Understanding the signaling pathways\r in SCC cells that regulate invasion will be important for developing improved cancer\r treatments. The signal transducer and activator of transcription 3 (Stat3) protein is a\r central regulator of numerous cellular activities, including proliferation, survival, and\r motility. Stat3 also has enhanced activity in many cancers, including skin SCC. This\r study shows that Stat3 regulates several invasive properties in a human skin SCC cell culture model.\r HGF (hepatocyte growth factor)- induced cell schattering was assessed for\r SRB12-p9 cells (p9WT), a human skin SCC cell line, along with SRB12-p9 cells\r engineered to have reduced Stat3 activity. Next, a cell viability-based adhesion assay\r was performed with these cells. Finally, severe combined immunodeficient (SCID)\r mice were injected subcutaneously with P9WT and S3DN cells and tumors were\r measured twice weekly. Extracted tumors were analyzed by immunohistochemistry and Western blotting for expression of the invasion related enzyme, MMP-2 and MMP-9.\r The suppression of Stat3 activity in S3DN cell lines resulted in reduced motility,\r greater adhesion, and a less invasive phenotype in SCID mice. Immunohistochemistry and Western blotting indicated higher levels of MMPs in the P9WT cells with\r expression localization towards the outer perimeter of the tumors. This data suggests\r that Stat3 plays a role in skin SCC invasion and better understanding of Stat3 function\r could lead to improved treatment and prevention of the disease.

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線鋁之情-以陽極氧化鋁模板製作氧化亞銅奈米線

我們使用陽極氧化鋁(AAO)模板來製備銅及其氧化物的奈米線。以硫酸銅和乳酸配製電鍍液,利用氫氧化鈉水溶液(NaOH)將其pH 值調整到12,供以不同電壓,可電鍍出銅及氧化亞銅奈米線。在較高電壓下可製備出銅奈米線,而在較低電壓下可製成氧化亞銅奈米線,若使用中間電壓則能製得銅及氧化亞銅的混合態。利用x 光繞射分析儀(XRD)來分析其結晶構造、使用場發射掃描式電子顯微鏡(SEM)以得知其表面形貌。電鍍出的奈米線直徑約60 nm。奈米線的長度可藉由調整電鍍時間或電壓來控制。在製作IC 內部導線方面,銅奈米線深具開發潛能;在提升太陽能電池的轉換效率、製作可見光光觸媒方面,氧化亞銅奈米線極具前瞻性。We electrodeposited copper and cuprous oxide (Cu2O) nanowires with anodic aluminum oxide (AAO) templates. Both Cu and Cu2O nanowires could be prepared with an alkaline cupric lactate solution, which was adjusted to pH 12 using a 6 M NaOH, when supplied with different electrolytic voltages. Cu nanowires could be prepared when a higher voltage was supplied, and Cu2O nanowires could be prepared with a lower voltage. A mixture of Cu and Cu2O nanowires could be prepared with a supply of a voltage in between. X-ray diffraction (XRD) is used to determine the phase composition, and scanning electron microscopy (SEM) is employed to characterize the morphology of the nanowires. The length of nanowires can be controlled by adjusting the time spent on electrodeposition and the voltage supplied. The resultant diameter of the nanowires was about 60 nm. Cu nanowires are promising materials for making the conductive wires in IC, and Cu2O nanowires hold great promise for improving the conversion efficiency of solar cells and manufacturing visible-light photocatalyst.

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Biosolids : Bio-transfer Factors of Trace Metals

With an increase in the use of biosolids as a soil replacement and as a fertilizer for crop production, consumers continue to question the safety of crops grown in biosolids.Although past research has shown that there are no adverse affectsin the nutritional value of plants grown in biosolids, I furtherresearched the safety levels of trace metals in crops fertilized using biosolids.

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Digital Viedo Compression Enhancement With Reduced Psychovisual Redundancy

Video compression is indispensable to web streaming and memory storage.Most video\r compression technology has difficulty to achieve high quality video at lower bit\r rates.Apparently,limited transmission bandwidth and network resources often degrade\r video signals.Thus the goal of my research was to enhance video degrade video\r signals.Thus the goal of my research was to enhance video compression performance and\r to improve visual quality.It is hypothesized that the reduction in neighboring pixels\r coding,and humans perceptual mechanisms(psychovisual)redundancy could produce a\r low-complexity geometry streams for animated visual objects.A set of algorithms is\r developed to parse bidirectional interpolation pixels into their characteristic cells,which\r vary in spectral energy and wavelength.The bits contained in these cells are vectorized and\r transformed recursively to identify lower correlations among vector arrarys for blocks\r filtering.DCT function calculates energy ratios between high spatial frequency and low\r spatial frequency,to devote most of the highest spatial frequency bits with the calculated\r energy ratios.A variable quantization method is used to measure the sensitivity of colors\r and its intensity ratios to restore any missing high spatial frequency pixels.presnted in\r mathematical intrinsic.This approach leads to the ability to compress video data that\r normally require a large amount of memory to store and high bandwidth to\r transmit,Results form the enhanced video compression experiment have attained\r 0.1bpp(256kbps,25fps)without noticeable effects comparable to the video compression\r technique that achieved 0.5bpp(1.5Mbps,25fps)in use today.

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