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本實驗在探討香草對蚊子的影響,用香草和一般較無氣味的雜草,來做實驗組和對照組,設計了兩大實驗。1.利用兩個箱子和一個連通管所製成的實驗箱,將植物水溶液噴灑於裝有20 隻母蚊子的箱中觀察由甲飛到乙、盤旋、垂直下降、及無反應等四種情況。得知艾草的驅蚊效果最佳,次之迷迭香、到手香,檸檬香茅最差,則其牠雜草效果不彰。2.手部實驗,將植物水溶液塗抹在手上,伸進裝有20 隻母蚊的實驗箱,停留一分鐘,觀察叮咬、停留在手上,等兩種情況。得知塗有香草的手蚊子比較少蚊子叮咬,效果為艾草最佳,次之迷迭香、到手香,最差檸檬香茅,而停留的數目,艾草最佳次之迷迭香、到手香,最差檸檬香茅,塗有雜草汁液的蚊子叮咬和停留的數目很多,幾乎沒效果。
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現時國民中學由於班級多,而實驗教室不敷使用,需在教室作示範實驗時,因實驗器材繁多,常有搬運不便之感,如將器具加以改良,可減少搬運時的麻煩,節省勞力和避兔器材的損壞。
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台灣稀有水生植物蓴菜生長型態構造觀察成分分析研究
本研究針對台灣產水生植物,蓴菜之構造與生長環境、蓴菜對腸胃道常見致病細菌之抑菌效果以及主要成分暨化合物分析。由本研究結果得知,崙埤湖內之稀有浮葉型水生植物蓴菜,其生長環境為無汙染之乾淨偏酸性水源,最適合生長之生深為50-160 ㎝;水溫則為22-25℃;而蓴菜之地下根莖對表皮金黃葡萄球菌(Staphylococcus aureus)具有輕度之抑菌效果,經由分離純化得知為BS-1:沒食子酸(Gallic acid);另外,由蓴菜之葉片分離出十種成分分別為BS-2 (Kaempferol-7-O-Glucosids)、BS-3 (Quercetin-7-O-glucosids)、BS-4(5,8,4’-Trihydroxyflavone-7-O-glucosids)、BS-5 (3,5,8,3’4’-Pentahydroxy flavone)、BS-6(Vitamin E: d-Tocopherol)、BS-7 (Glyceride)、BS-8 (Phenolic A)、BS-9(Quercetin)、BS-10(Kaempferol)、BS-11(Phenolic B)。其中發現BS-8 對神經膠腫瘤細胞株有18.42%之抑癌效果,另外,BS-2、BS-3、BS-5、BS-10、BS-11 等成分,呈現良好之美白作用。This investigation is to analyze Brasenia schreberi Gmel., a native rare floating water plant in Taiwan, focusing on the plant’ s structure, its growth environment and, most importantly, the effect of chemical compounds it produces on restraining the common pathogenic bacteria in human stomach. The result indicates that the most suitable growth environment for Brasenia schreberi Gmel. is in slightly acid, pollution-free water such as that in the lake Lung Pi in northern Taiwan. The ideal water depth for its growth is 50-160 cm, and the water temperature is 22-25°C. The impractical BS-1 (Gallic acid) extracted from the izome of Brasenia schreberi Gmel. by separation and purification has a light effect on restraining Staphylococcus aureus, a bacteria in the stomach. From the epidermis of the blade of Brasenia schreberi Gmel., ten other ingredients are also isolated, including BS-2 (Kaempferol-7-O-glucosids), BS-3 (Quercetin-7-O-glucosids), BS-4 (5,8,4’-Trihydroxyflavone-7-O-glucosids), BS-5 (3,5,8,3’,4’-Pentahydroxyflavone), BS-6 (Vitamin E: d-Tocopherol ), BS-7 ( Glyceride ), BS-8 (Phenolic A ), BS-9 (Quercetin), BS-10 (Kaempferol),and BS-11 (Phenolic B). BS-8 is found to resist cancer C6 ( Glioma ) by 18.42%, while BS-2,BS-3, BS-5, BS-10, and BS-11 show an outstanding effect on skin-whitening.
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Tea is the most widely accepted and consumed beverage worldwide due to its characteristic aroma and taste. Recent studies have provided the strong scientific basis for understanding the health promoting effects and cancer preventive actions of tea. The components of tea especial the catechins are varied with the conditions of making tea. To understand and determine the chemical composition of tea is very important. Some investigations of the parameters on the storage and making of tea were carried on in this study. The kinds of tea studied were including black tea, oolong tea, green tea, and instant tea bags. A high performance liquid chromatograph combined with UV detector and mass spectrometer used to analyze the components of tea. The results showed that the composition of tea solution is dependant of the exposure of light. One of the components of tea, (-)-epicatechin methylgallate (ECMG) was oxidized to quino form. The concentrations of (-)-catechin gallate (ECG) decreased and one of new compound (M.W. 442) produced with increasing the storage time. From the results show tea made with cold water is better than that made with hot water. The ingredients in green tea were changed faster than those in fermentative black tea and oolong tea. The components of tea can be kept unchanged for a long time at low temperature. In refrigerator, the time can be extended to overnight. 茶由於其具有特殊的芳香氣味及口味,廣泛地被世人用為飲料,近年來的研究證據顯示茶具有促進身體健康和防癌功效,但茶中成分之變化,尤其兒茶素隨茶的種類、茶沖泡保存方式及置放時間而有所不同,因此對於茶中成分及沖泡方式的認知是一門重要的課題。 本實驗主要是探討茶沖泡時間及貯存條件,對於茶液所含兒茶素變化的影響,探討的茶包含紅茶、烏龍茶、綠茶及其茶包。並使用質譜儀及高效能液相層析質譜儀配備紫外光偵測器分析茶液中之成分,實驗結果顯示成分變化速率以未發酵的綠茶較發酵的紅茶和烏龍茶快;低溫儲存時,亦可延緩茶液成分的變化,例如加蓋並存放於冰箱,則茶置放至隔夜其成分均未改變;同時結果顯示成分產生變化者,主要為兒茶素氧化,如將多酚類氫氧基經氧化變成?(quino) ,其次為斷裂再產生聚合其中綠茶以不照光變化較大。本研究並經實驗發現如果以冷開水沖泡綠茶20~30分鐘,咖啡因的溶出量雖略多於沖泡2分鐘的熱茶,但各種兒茶素的溶出量卻遠高之,尤其置放至隔夜茶液成分仍無氧化現象。
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結合Hamiltonian與Hiroimono的路徑研究
Hamiltonian和Hiroimono路徑問題都有百年以上的歷史,且沒有直接解決方法,可能因為是題目本身的條件在討論時尚不足解決問題,現階段只能用電腦去跑。
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本校的楊老師在朝會時,向我們報告每位同學要捐獻 1公斤的度紙廢物,把變賣的金錢做為仁愛工作基金。我們聽了很贊成,放學回家後,就在家裹找尋廢物,因此舊衣服、舊書報、破簿子都成了我們蒐集的對象,大家東翻西找,都希望多捐些東西,誰也不願落後,陳光明同學在尋找廢物時,突然發現一種身體銀白柔軟的小蟲,在舊衣服和舊書堆爬動,引起陳同學的好奇心,這是什麼蟲?呢?於是捉了一隻,帶到學校向老師請教,老師告訴我們這是一種昆蟲一一衣魚。對於人類的生活有害無益,大家非常好奇,也覺得很有趣,因此我們想對它多一認識。
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問題與想法:邊長1的正三角鏡ABC中,光由原點B射到CA上一點P(圖一),再依反射定律繼續反射下去,我們想探討:是否能回到原點B?而若回到原點B,所走路徑及反射次數可找到通式?考慮圖二探討此問題。圖二中的每一頂點都對應△ABC中每一頂點。主要結論:我們算出每一反射點在圖二中的座標得以下結論: (1)CP為有理數時,CP=b/a,(a,b)=1,a,b∈N,導出第一個相交頂點在展開圖的座標為(a-b,b)。再利用展開圖中,同名點構成的直線特徵(如圖三)得:由B射出光時,會返回原點B。並知反射後回到B所需的次數與路徑可由a、b決定,公式如下:若a+b≡0(mod3),次數為2(a-1)次,路徑為B→B 若a+b≡1(mod3),次數為6(a-1)次,路徑為B→C→A→B 若a+b≡2(mod3),次數為6(a-1)次,路徑為B→A→C→B (2)當CP為無理數時,我們得到由B射出的光線不會返回B。且所有無窮多的反射點,在邊上的分布具有稠密性。
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我們經常利用星期假日到野外郊遊與採標本,於途中常可見到多種的蔓生植物攀衍於草叢、竹林裹或在籬笆、屋頂上。其中以牽牛花為數最多,因此使我們產生強烈的好奇心走近觀察研究,但卻發生一個疑問,那就是牽牛花的蔓子是不是自己會邊找可做支柱的東西而攀附上升呢?雖經大家紛紛發表意見討論.但是最後,也是沒有辦法解開這個謎,便請教老師,經過老師解說,心中仍疑惑不解,為獲得更有力的證實,又請教老師指導我們實驗、觀察牽牛花尋找支柱的研究。
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The Interplay of Iron and α-synuclein in mediating Neuroinflammation in Parkinson’s Disease
Neuroinflammation is implicated as a contributive factor to neurodegeneration in Parkinson’s disease (PD). Increased iron accumulation and deposition of -synuclein within Lewy Bodies in PD brains have been observed. It has been hypothesized that unbound iron is able to react with H2O2 to generate free radicals. Using the Divalent Metal Transporter-1 (DMT1) as a vehicle to transport iron into the brain, a DMT1 transgenic mouse model (DTg) was generated to recapitulate iron deposition in PD. The DTg was crossbred with the SNCA (synuclein) transgenic mouse to produce a DMT1_SNCA (BTg) mouse model to study the link between iron, -synuclein and neuroinflammation in PD. Our hypothesis predicts that iron exacerbates -synuclein toxicity by inducing larger inflammatory responses and consequently compromising functions of biomolecules. Our study shows that –synuclein triggers a low-grade inflammatory response by microglia and astrocytes while iron exacerbates -synuclein toxicity by eliciting immunological responses mediated by glia cells in the brain observed both in the DTg and BTg mice. Elevated levels of nitrated proteins were observed in the DTg, suggesting the role of iron in inducing nitrosative stress via upregulation of iNOS in glia cells. With the BTg mice, we hope to understand the effect of iron accumulation as an environmental stressor in aggravating -synuclein toxicity which may lead to the selective demise of dopaminergic neurons.
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Drawing versus Clay
1. Purpose of Research / Project The purpose of this research was to find out whether clay has any diagnostic value as a three-dimensional medium compare to drawing which is two dimensional medium and to determine if learners would prefer to work with clay or to rather draw a picture when depicting their ″feeling-stories″. Furthermore to do research on the effect that different coloured clay has on the emotions and behavior of learners during therapy. 2. Procedure A number of learners from different backgrounds, ages and cultures were used in this empirical research. They were asked to draw a ″feeling-story″ with a two-dimensional medium and then depict a ″feeling-story″ with different coloured clay which is a three-dimensional medium. Afterwards they had to describe their stories. They also had to choose what they liked best-the two-dimensional medium (drawing) or the three-dimensional medium (clay). 3. Data From the results it was clear that clay projections have diagnostic value. The learners were able to communicate their ″feeling-story″ better by using the three-dimensional figures in a verbal and non-verbal way. Through actions and the choice of coloured clay they used, they could portray and describe their emotions and symbolic messages. This indicated that they enjoyed the clay projections more than the drawings they made. 4. Conclusion From my research I found that clay as a three-dimensional medium has diagnostic value and can be applied as a supplementary projection medium. Different coloured clay can be associated with different emotions and behaviours in children. More learners preferred to work with clay (three-dimensional) as a medium in depicting their ″feeling-story″ rather than drawing two-dimensional pictures.
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沖沖沖!石頭石頭我不怕~探討水的力量對大自然的災害及其防治之道
為了探究「水的力量」對大自然的影響,本組以抽水馬達、水位控制器、連通管、三通開關、大塑膠盆及電子秤等儀器,組成「水流沖力控制儀器」。實驗中:測得水位高度和水速平方成正比,而與出水口孔徑大小無關;以直立電子秤測得水的沖力與水速平方成正比;利用小石頭製成河床,並以密度與石頭相近的正立方體鋁塊受水流沖擊,推測出沖走鋁塊的最大重量和水速四次方以上成正比;利用陶土混水製成不同密度的泥漿,模擬土石流的流動情形;設計了梯形、倒梯形、河壩、倒河壩及丁壩等五種河道,測試發現河壩型河道最能減緩水流速,明顯地降低水流的沖擊力;改做不同階梯密度的減速模組,並以軟體Tracker輔助分析,得知低密度階梯減速模組,減速效果最佳。
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隨著物理、化學、生物等各學科的成熟,使得新興的復合學科成了當今炙手可熱的焦點,例如:生化科技(生物+化學)、奈米技術(物理+化學+生物)等,當然,它們也帶動了人類世界相當大的進步。因此,生活中看似理所當然的現象,若從不同學科的角度觀察,或許也能得到意外的收穫。本研究主要是以「物理光學的角度」分析「昆蟲複眼的視覺感受」研究的現象從「驅趕蒼蠅的清水袋」出發,試圖找出影響蒼蠅視覺最敏感的水袋顏色。然後,再以此種色光為主要,配合物理光學的成像知識與製作昆蟲複眼的巧思,分析「不同結構的複眼」在接收該色光後,其視網膜「成像的偏異情形」研究結果的發現有二;第一,複眼對紫光最為敏感,這樣的結果與「某些昆蟲複眼僅能看到短波長色光」的說法不謀而合。第二,從物理光學的角度亦能證實生命科學的說法,即「昆蟲的複眼曲度越大,對光線越為敏感」、「昆蟲複眼中小眼越多,對光線越敏感」等等。因此,本研究成功地用物理的方法解釋了昆蟲複眼的視神經感受,如此微妙結果,到底是意外呢?還是科學的神奇之處?一切的一切,將在以下的內容中說清楚、講明白....
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