利用雷射光實驗研究液的折射率梯度
溶液和溶劑置於同一容器中，當溶質向上擴散時，會形成濃度梯度及折射率梯度 dn/dy，且dn/dy 對高度y 的關係圖會呈現隨著高度改變的現象。 半徑r 的Ｄ形容器，下方置溶液，上方置溶劑，以雷射光照射容器的平面部份時， 雷射光沿著法線出射，受折射率梯度的作用而向下偏Ζ距離，a 為容器至屏的距離， 得到dn/dy=Z/ar 的關係式；改變雷射光的高度y 可得dn/dy 圖。 以硫代硫酸那作實驗，其dn/dy-y 圖為以原始界面為對稱軸，因其擴散係數不隨濃 度改變；甘游水溶液的dn/dy-y 圖呈現不對稱，圖形的極大值往甘油方偏，主要係因 為甘油的擴散係數隨濃度的增大而減少。 我們成功第把不同時間對同一溶液的實驗結果予以模型化，得到的dn/dy-y 曲線隨 時間改變，並發現該曲線所涵蓋的面積為定值。 雷射光經光柵再照射半圓筒，可直接測出各高度的折射率，量出y、 dn/dy、n、及濃度可算出擴散係數。The mixing between a pure liquid and a solutionin a vertical column produced a concentration gradient , which in turn produced the refractive index gradient . As the solute particles diffused upward into the pure liquid , a gradient was generated because of the varying solute concentration . The plot of the refractive index gradient versus vertical position y (dn/dy vs y) is found to vary with time . A D-shape container of radius r is partly filled with a dense solution , and partly filled with solvent which is on the top of the solution. When laser beam pendicularly enters the flat surface of the container, the outgoing beam strikes the container at a normal incidence , and is deflected down a vertical distance Z by the refractive index gradient . We can get dn/dy=Z/ar , where a is the distance between the container and the screen . By changing the vertical position (y)of laser beam , we can get the plot of dn/dy vs y . We have successfully modeled the time dependent experimental gradient curves on the same solution . The area beneath the trace of dn/dy vs y at different time is found to be constant . Additionally, with a grating at the center of the semicircle, we can measure the index of refraction n and get the plot of n vs y. The diffusion coefficient D of the solute can be calculated using the plot of dn/dy,y,and time t.
高中各學期成績與指定考科相關性
在升學主義越來越興盛的社會中，考試成績成為人人關心的重點，這\r 次研究就是藉由數理資優班同學的各學期在校成績和指定考科成\r 績，透過迴歸分析，找出各學期成績與指考成績之間的關係，並利用\r 圖表來解釋各種科目在各學期的課程，在高中三年所學的重要性，在\r 藉由此結果，希望能對目前老師的教育重點及學生學習方式能有所幫\r 助，亦可了解學生在高中求學過程中，哪些階段對指考成績較有正面\r 影響，進而強化該學習階段，以有助在指定考科時能充分發揮所學。\r \r In a society that emphasize on degrees, examination scores become the\r spotlight, and the ultimate goal for a high school student who had worked\r so hard for three years is to achieve high scores in the J.C.E.E. In the\r three years of high school, each subject has different topics each semester,\r but which semester has the most decisive effect on the J.C.E.E. score?\r This research is to study the effect of each semester on the J.C.E.E. by\r analyzing the grades of a science and math talented class in Senior High\r School using Regression analysis to find out the connections between\r term grades and the J.C.E.E. Then finding out which term grades had the\r most decisive effect in each subject. By using the result, we hope it can\r help teachers in their teaching and students in their learning. Also, it can\r provide the information about which stage in high school has positive\r effects on J.C.E.E. grades, therefore enabling students to emphasize on\r that stage in order to perform well on the J.C.E.E.
包埋酵母菌的幾丁球珠對含銅、鐵、鋅、鉛離子之廢水處理及應用
本實驗的目的，就是希望利用幾丁質除污的效果，再配合酵母菌所能累積金屬的能力，以酵母菌包埋於幾丁質的方法，吸附廢水中的重金屬離子。用Langmuir理論求得飽和吸附量，進而求出休眠酵母菌-幾丁質所能吸附金屬離子0.14─0.027(g/g)的數量，與活化酵母菌-幾丁質所能吸附金屬離子1.15─0.050(g/g)，並比較回收效率，以應用於處理工業上工廠所排放的廢水。 筆者在偶然的機會將處理過的蟹殼幾丁質固體置於石綿心網上，竟然在數分鐘內像塑膠般熔化，探討原因竟然是石綿心網上的某些金屬鹽所造成，因此筆者希望能透過這發現，用簡單的方法製造出低去乙醯化、高強度及耐中度酸的幾丁基質，並可應用在廢水處理上。;The purpose of this experiment is to explore the effect of using chitin and yeast plat to clarify the heavy metal cation, and that yeast plat works on the accumulation. In the process, the yeast plat is embedded in chitin to absorb the metal cation, therefore, by the theory of Langmuir, the impregnate absorption of dormant yeast-plat-chitin (0.14-0.027[g/g]) can be obtained and yeast-plat-chitin (1.15-0.050[g/g]) can be activated as well. In this way, the efficiency can be compared to apply to work on the effluent in industry. By putting shell-chitin-solid on the wire gouze by chance, we found it melted like plastic in just a few minutes. Some kinds of metal salt on wire gouze cause this change. Therefore, this easy ways can be used to makelow-deamide function group become of high strength and durable under acid environment. The results obtained from this experiment can be applied for the processing of waste liquid.
台灣不同世代A 群鏈球菌對紅徽素抗藥性之研究
A total of 64 nonduplicate isolates of erythromycin-resistant (MIC, >1 μg/ml) Streptococcus pyogenes collected from 1979 to 2003 in Taiwan were evaluated. They were collected from three cohort period: 1979 –1989, 1990-1999 and after 2000. The in vitro activities of 10 antimicrobial agents were determined by the agar dilution method. Penicillin, cephalothin, cefotaxime, vancomycin, and ofloxacin were shown to be active against S. pyogenes isolates (100% sensitive). Erythromycin and azithromycin both had poor activities (MIC50s, 16 and >128 μg/ml, respectively; MIC90s, >512 and >128 μg/ml, respectively). The activities of tetracycline, clindamycin, and chloramphenicol against a significant number of these isolates were also limited. Among the 64 S. pyogenes isolates, 58% had constitutive resistance [cMLS], 40% had an M phenotype and 2% had an iMLS phenotype (inducible resistance [iMLS]). A substantial upsurge in the incidence of M phenotype erythromycin-resistant isolates was found with time for S. pyogenes (10% in 1979–1989, 48% in 1990–1999 and 65% after 2000). The erythromycin resistance genes in 64 isolates of the different cohorts were investigated by PCR. All cMLS phenotype isolates tested had ermB gene. The M phenotype isolates had only the macrolide efflux (mefA) gene. This study shows the secular changes of increasing susceptibility of S. pyogenes isolates to both erythromycin and clindamycin in Taiwan. The mechanisms of erythromycin resistance have changed from the predominance of ermB gene (cMLS) to mefA gene (M phenotype). 本研究是探討台灣自1970 年代末期以來不同世代A群鏈球菌菌株對紅黴素的抗藥性及抗藥基因特徵的演變。研究者收集台灣二十年前(1980 年代前後，第一世代)、十年前(1990 年代，第二世代)、)及最近(2000 年以後，第三世代)之A 群鏈球菌菌株共64 株，利用抗生素圖譜和雙藥錠擴散測試及聚合?連鎖反應(PCR)、和脈衝式膠體電泳研究A 群鏈球菌對紅黴素抗藥性的表現型及基因型特徵。結果發現第一世代的A 群鏈球菌對紅黴素最小抑菌濃度(MIC)值相當高，幾乎都是>512 μg/ml，90%為多重抗藥菌株。第二世代則相對有降低，在第三世代此現象更明顯，多重抗藥菌株為30%。在雙藥錠擴散測試結果，從第一世代來看cMLS 佔大多數(90%)，M 型佔10%；第二世代cMLS 及M 型相當分別佔52%及48%；第三世代主要為M 型佔65%，cMLS 佔30%，iMLS 佔5%。利用PCR研究紅黴素抗藥性基因發現所有cMLS 菌株皆有ermB 基因，所有M 型菌株皆有mefA 基因，iMLS 菌株則有ermTR 基因。由本研究顯示在台灣A 群鏈球菌對紅黴素之抗藥性隨著不同世代有逐年改善之趨勢，由MIC50的降低可看出，菌株對紅黴素的敏感性提高，可為臨床治療之參考。
Salinity effects on Duckweed growth
The purpose of this research was to investigate the most favourable salt concentration that promotes growth in the Lemna minor plant. Lemna minor, commonly known as lesser duckweed, is found growing among other aquatic plants or massed together in still or slow moving fresh water, such as ponds and lakes, in warmer regions around the world.
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.
Energy-Transformation Railway System
There are numerous problems caused by today's railway system. This makes Hong Kong a less attractive place to live in. We have to tackle these problems in order to make Hong Kong a better place. Our model can recycle the energy dissipated in the rail vibration, reuse the sound energy produced by the wheels and the rail by a sound energy conversion system, recycle the wind power in the tunnel by a new type of wind turbine, the Wind Power Generator Underground (WPGU), recycle the thermal energy produced by the air-conditioning system of railway stations by a new system, the Thermal Energy Conversion (TEC). When the rail is bent, the magnets attached to it are also pulled down. When the rail returns to its original position, the magnets attached to it are pulled out of the coils. In both cases, the magnets move against a force. The work done to move the magnets against the force is converted to electrical energy. Also, the bottom of the MTR is designed to be curved. The sound waves produced by the contact point of the wheels and the rail directing towards the bottom of the MTR would be reflected to an elastic material which has a number of magnets attached to it and corresponding number of solenoids are fixed on the ground below the magnets. Sound energy can be converted to electrical energy in this case. When a train approaches or passes through the section that the WPGU is installed, wind is generated. The wind forces the wind turbine to rotate at a certain high speed. The turbine transmits the rotation to the coils in the dynamo, and hence electricity is generated. Heat released from the air-conditioner is absorbed by water. The hot water is then pumped into the system. As the hot water in the pipe flows through the evaporator, liquid ammonia inside will evaporate and flow into the electricity generator. Inside the electricity generator, the gas will push the turbine to rotate and hence electricity is generated. The ammonia gas is then condensed in the condenser and flows back to the evaporator. Hence ammonia is used circularly. In order to explain our principle, we would like to introduce the Lenz's Law, an induced current flows in such a direction as to oppose the movement that started it, the Faraday's Law of electromagnetic induction, the induced electromotive force in a circuit is equal to the rate of change of magnetic flux through that circuit, the Law of Conservation of Energy, energy can neither be created nor destroyed, but can transform from one form to the other.