明察秋毫-金屬的熱膨脹
Thermal expansion exists in our daily life. However, thermal expansion is generally too slight to be seen by naked eyes. Therefore, in the present project, a dilatometer was assembled to enhance better sensitivity toward thermal expansion. Hopefully the self-assembled dilatometer could contribute to teaching purpose.The structure of our 4th generation dilatometer is showed below. Using an ‘L’ square to hang up the metal stick and a rolling needle with a mirror to reflect the laser light are the critical parts of this equipment. By using this special reflection mechanism, the slight expansion of a metal stick caused by heat can be enlarged to a large scale. This special mechanism is where our creativity laid. Measuring in millimeter (mm), the measurement precision of the equipment can be extended to 0.0001 decimal. Our dilatometer was used to measure the expansion of various metal sticks caused by the temperature changes. Results were drawn from analysis of the data: 1) The average relative deflection was within 1.0~1.8%; 2) The relative deviation of linear thermal expansion coefficient was within –1.2~-4.4%.
物質熱漲冷縮的特性普遍存在於我們的生活環境中,但因其變化量相對微小,一般並不容易直接觀察,爲了進一步研究這課題,我們組裝偵測熱膨脹的儀器,並希望儀器的靈敏度高,能推廣為教學器材,經過我們不斷努力與改良,終於有了令人愉悅的成果。
自製第四代熱膨脹儀的結構如圖,設計「角尺懸吊金屬棒」與「滾針及鏡面反射」是儀器的重要部份,利用滾針旋轉及鏡面反射雷射光,加乘放大熱膨脹的微量變化,這是我們主要的創意,以公厘(mm)為單位,儀器的精確值到小數第四位。
利用自製的熱膨脹儀,探討金屬熱膨脹的影響因素。分析實驗所得數據,平均相對偏差在1.0~1.8﹪,而線膨脹係數的相對誤差約-1.2~-4.4﹪。
馬纓丹? 變!變!變!
Lantana is a very common plant in our lives. It grows easily and it has a long florescence and various colors. The colors of particular types of lantana alter as the changing florescence. In this experiment, paper chromatography, high-performance liquid chromatography, SDS-gel electrophoresis, the measurement of petal cellular pH values, and the comparative study of forms of trachoma on the epidermal cells of petals are exerted in order to explore factors that change the colors of the lantanaThe findings are as follows:\r (1)Lantana’s colors have inseparable relationships with the compositions of anthocyanins and flavonoids, but not with the pH values of petal cells.(2)The anthocyanins of petal cells are cyanidm, with glycosides as well.(3)Beside the differences in the compositions of pigments, the forms of trachoma on the epidermis of the petal, cone-like or caniniform, can also be used to distinguish different types of lantana, because the trachoma can influence the reflections of light from the epidermis of the petals and also affect colors of the flowers.(4)The result of SDS-gel electrophoresis shows that the biochemical pathways of petal cells in all species of lantana are similar, so we assume that there is mutant in the series of synthesizing enzyme when the anthocyanins of petal cells are formed, and thus, there are no anthocyanins appearing in the yellow and white species of lantanaThe results above are helpful for the understanding and discovering of lantana’s biological mechanisms, and can be used to create new types of lantana and to make further study of the metabolism of lantana’s complete anthocyanin’s biochemical pathway馬纓丹(Lantana ssp.)是常見景觀植物,容易栽種、花期長、花色多,且有些品系花色會隨著花期而變化。本實驗利用濾紙色層分析、高效能液相層析、SDS-gel電泳、細胞pH值測定及花瓣表皮細胞之毛茸(trichoma)型態之比較等方法探討馬纓丹花色之不同及變化的原因。結果顯示: (1)馬纓丹的花色及花色變化與花青素(anthocyanins)和類黃素(flavonoids)之組成有密切關係,而與花瓣細胞內pH值無關。(2)花瓣中所含花青素為矢車菊色素(cyanidm),並且具有配醣基(glycoside)。(3)花瓣表皮細胞之毛茸型態,如圓錐形或犬牙型,會影響光的反射,進而影響花色,所以毛茸型態可做為區分馬櫻丹品系之特徵。(4)SDS-gel電泳的結果顯示,馬櫻丹各品系的花瓣細胞生合成類似,推測花瓣細胞產生花青素的一系列酵素中,已有突變發生,而造成黃色、白色品系無花青素。以上結果有助於了解馬纓丹花色變化之機制,可將其應用於改良出新的馬櫻丹之品系,或更深入研究馬櫻丹花青素完整生成代謝路徑。
鬼腳圖的數學原理
We can prove 鬼腳圖 have an one-to-one characteristic; it is mean that you can not design a 鬼腳圖 which will make two starting point to the same end. We also can prove you can design any 鬼腳圖 you want; you can predict a result, and you can design a 鬼腳圖 which suit the result, no matter what the result it is. We can design any 鬼腳圖 we want, but it possibly becomes very big and complicated. We develop a method to make it become briefer. According to the method, we make a function that can design the 鬼腳圖 you want in a very short time. You predict a result in computer, and the\r function will design a 鬼腳圖 which suit the result, and it will be the briefest. 吾人已經可以證明鬼腳圖具備一對一的性質,意思就是:不可能從兩個起點開始畫線,最後到同一個終點上。吾人亦證明:鬼腳圖的結果沒有限定:同一組初始條件可以轉換成任何一組結果。而同一組結果也有許多種不同的畫法,顯示鬼腳圖的畫法不具唯一性。即使如此,畫出來的鬼腳圖可能過於複雜,於是吾人又發展出簡化鬼腳圖的方法,可畫出較簡潔的鬼腳圖。吾人並根據這種化簡方式編出一套程式,只要將欲得的結果輸入,電腦就可以畫出最簡潔的鬼腳圖。
橘子甜了
從研究抑制乙烯的實驗中碰巧得到的靈感,讓我們找到了水果中一種不可思議的變化,水果在撞擊之後乙烯量會增加,因而帶動水果的糖度上升,甜度增加!! 我們利用水果內的逆境機制,使得水果在外界刺激之下(如:撞擊),出現加速成熟的效果。我們經由多次的實驗,在各種水果的數據中,分析變甜的原因,及與乙烯量增加、pH 值下降的相互關係。並且找出除了搖動外,其他可以使水果糖度增加的方式。有了這些方法,我們可以在家中自行加工水果,使未成熟的水果快速成熟、使已經成熟的水果更甜,再也不會因非產季而妨礙到吃的興致!! We get an inspiration form the experiment for controlling ethylene. We find an unimaginably different change of fruits. After ramming, the amount of ethylene in the fruit will increase. This makes the sweet degree of the fruit increase, and it tastes more sweetly!! With adversity system of fruit, we make fruit ripe quickly by external excitement.(ex: ram)Through many experiments and the data of all kinds of fruits, we can assay the reason for fruits’ becoming sweeter, and interrelation between increasing ethylene and decreasing pH value. And find other ways except for shaking to make sugar degree rise. With these ways, we can process fruits by ourselves at home. We can make unripe fruit mature quickly, make ripe fruit sweeter, and we will no longer be obstructed to eat fruit even if it won’t be produced in that season.
移動棋子問題的致勝策略
We consider a game played with chips on a strip of squares. The squares are labeled, left to right, with 1, 2, 3, . . ., and there are k chips initially placed on distinct squares. Two players take turns to move one of these chips to the next empty square to its left. In this project, we study four different games according to the following \r rules: Game A: the player who places a chip on square 1 wins;Game B: the player who places a chip on square 1 loses;Game C: the player who finishes up with chips on 12 . . . k wins;Game D: the player who finishes up with chips on 12 . . . k loses. After studying the cases k = 3, 4,5 and 6 for Game A and the relation among these four games, we are led to discover the winning strategy of each game for any positive integer k. The strategies of Games A, B and C are closely related through a forward or backward shifting in position. We also found that such strategies are similar to the type of Nim game that awards the player taking the last chip. Game D is totally different from the rest. To solve this game, we investigate the Nim game that declares the player taking the last chips loser. Amazingly, the strategies of two Nim games can be concisely linked by two equations. Through these two Nim games, we not only find the winning strategy of Game D but also the precise relation between Game D and all others.\r 去年我研究一個遊戲:有一列n個的方格中,從左至右依序編號為1,2,3,....n。在X1個、第X2個、第X3個格子中各放置一個棋子。甲乙二個人按照下列規則輪流移動棋子:\r 一、甲乙兩個人每次只能動一個棋子(三個棋子中任選一個)。遊戲開始由甲先移動動棋子。二、甲乙兩個人每次移動某一個棋子時,只能將這個棋子移至左邊最近的空格(若前面連續有P個棋時可以跳過前面的P個棋子而且只能跳一次),而且每個方格中最多只能放一個棋子。\r 研究這個遊戲問題時,我討論四種不同"輸贏結果"的規定:甲乙兩個人中,A誰先將三個棋子中任意一個棋子移到第一個方格,誰就是贏家。B誰先將三個棋子中任意一個棋子移到第一個方格,誰就是輸家。C誰先不能再移動任何棋子,誰就是輸家。D誰先不能再移動任何棋子,誰就是贏家。\r 當"輸贏結果"的規定採用ABCD時─我們稱為遊戲ABCD。今年我將把這個遊戲問題中棋子的個數由三個推廣到一般K個情形之後,再繼續研究遊戲的致勝策略,同時也將研究遊戲ABCD之間的關係。
重金屬錯影響細胞生理功能的研究
儘管鍺在電子工業上被廣泛運用,但對於暴露在鍺化合物所產生的毒害則尚未被詳細的探討。在探討鍺對細胞所產生的生理影響中,我們使用了二氧化鍺 ( GeO2)和有機鍺( Ge-132 )。由實驗結果顯示, GeO2,會造成人類子宮上皮癌細胞( A 431 ) 及巨噬細胞株( Raw264.7 )死亡,而 Ge -132 對細胞生長則不造成任何影響,為了進一步了解鍺引起細胞死亡是否是經過細胞凋亡(apoptosis ) ,我們將鍺處理過的細胞進行染色體 D NA 的分析,結果發現細胞中 DNA 染色體沒有斷裂。由先前 Huang 等人於 1999 年的研究結果顯示,砷對細胞所造成的毒性是經由有絲分裂活化酵素( MAPK )傳導路徑,所以為了解鍺誘導細胞死亡的路徑,我們亦分析 MAPK 傳導路徑是否亦參與其中,我們發現 GeO2加入 A431 細胞後,會活化有絲分裂活化酵素中的 ERK ,但對JNK 及 p38 皆無影響,在對蛋白質表現方面,轉錄因子 c-Jun 的蛋白質表現也是隨著GeO2加入的時間增加而上升。 GeO2加入 Raw 264 . 7cell 後,會造成 JNK 、 ERK 的活化,同樣的轉錄因子 c- Jun 也會增加,由此一結果得知鍺對細胞的影響會因細胞的不同而有所差異,為了分析自由基是否參與砷及鍺所造成細胞死亡的過程,我們分析在 A431 細胞中可產生的 NO 的可誘導性 nitric oxide synthase ( iNOS )的表現,我們發現氧化鍺及砷都會誘導 iNOS 的表現量增加。綜合以上結果,可能顯示氧化錯可能會經由 M A PK 訊息傳遞路徑來促使細胞的死亡,並且 iNOS 亦可能參與此過程。就我們所知,這是第一個提出重金屬所造成的毒害可能會經由 iNOS 來誘導產生的研究。
Despite the extensive use of germanium (Ge) in the electronic industry and optical devices, the potential risks of exposure to germanium compounds have not been evaluated. The effects of germanium on cell physiological functions were studied. We first asked if germanium oxide (GeO2) or carboxyethylgermanium (Ge-l32) could affect cell viability. We found that GeO2, but not Ge-l32, reduced cell viability in a dose-dependent manner in epidermoid carcinoma A43 I and macrophage Raw 264.7 cells. In order to test whether apoptosis contributes to germanium cytotoxicity, DNA fragmentation was evaluated in A43 1 and Raw 264.7 cells treated with GeO2 or Ge-132, respectively. We found that neither GeO2 nor Ge- 132 had effect on chromosomal DNA fragmentation. Previous studies by Huang (1999) et al indicated that sodium arsenite (NaAsO2) cytotoxicity is mediated through mitogen-activated protein kinase (MAPK) pathways. In order to study the mechanism(s) by which GeO2 mediates cell death, we analyzed the signal transduction pathways triggered by GeO2 We found that GeO2 stimulated the extracellular signal-regulated kinase (ERK) activity and transcription factor c-Jun in a time-dependent manner, but not c-Jun amino-terminal kinasc (JNK), or p38 MAPK in A431 cells. Treatment of the Raw 264.7 cells with GeO2, induced activities of ERK, JNK and c-Jun in a time-dependent manner. Collectively, these results suggested that GeO2 effects might be cell type specific. To test whether free radicals were involved in NaAsO2 or GeO2 mediated cell death, the expression of inducible nitric oxide synthase (iNOS), which produced the NO free radical, was determined in A431 cells treated with NaAsO2 or GeO2. We found that expression of iNOS was induced in a time-dependent manner in NaAsO2 or GeO2-treted A431 cells. Taken together, our results indicated that GeO2-induccd cell death may be mediated through MAPK signal pathways and that iNOS may contribute to NaAsO2 or GeO2 mediated cell death. To our knowledge, this is the first report that iNOS may contribute to heavy metal mediated cytotoxicity.