全國中小學科展

三等獎

見微知「駐」-水珠律動與圓駐波

It is always fascinating to see water droplet’s dancing around on a Japanese teppanyaki hotplate surface. The water usually does not evaporate immediately, but form interesting shapes, dance around and follow by evaporation of gaseous water and disappear. In this experiment, we designed a very simple experimental set-up to observe the little water droplets dancing on a heated hotplate. A homemade stainless plate and a small heater attached to the plate, and a thermal couple was assembled. With this simple setup, we observed the variation of water droplet’s shape as a function of the hotplate temperatures. The temperature of the water droplets, the duration of the water on the hotplate, and the shape number were measured. The shape formation mechanism was proposed. We found when the water droplet was subject to high heat due to the contact of the surface and the hotplate, the abrupt evaporation of the water molecules and violent vibration cause the formation of the various shapes to reach thermal equilibrium; the number of the shapes and the oscillation can be described by Laplace’s equation,Using a high-speed camera, we found the higher the temperature of the water, the more variations of the water droplet shapes can be observed. In addition, at a certain temperature range, the number of the water shapes did not change, suggesting a similar phase transformation behavior on the shape formation. 緣起: 邂逅專題研究、水珠漫舞、剪輯影片,引起我們想更進一步揭開它的神秘面紗。 緣續: 了解熱平台上水滴大小的變化及水珠基本的形狀及變化律動。 緣繫: 進一步研究水珠多變的面貌,並探討水珠的大小、溫度、停滯時間及變化規律相關機制。 緣定: 糾纏在水珠圓舞曲中有如大珠小珠落玉盤的曼妙,其中埋藏了平均圓與能量量子化的律動。

幾丁聚醣包埋酵母菌球株對重金屬離子廢水處理

本實驗的目的,就是希望利用幾丁聚醣除污的效果,再配合酵母菌所能累積金屬的能力,以酵母菌包埋於幾丁聚醣的方法,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-幾丁聚醣所能吸附金屬離子(銅)0.2048(g/g)的數量,與活化酵母菌-幾丁聚醣所能吸附金屬離子(銅)0.1750(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. In this experiment , we want to use the ablation of chitosan and the accumulation in metal of saccharomycete to absorb the metal cation of waste liquid . In the process , we embedded the saccharomycete in chitosan to absorb the metal cation , and obtained the impregnate absorption of dormant saccharomycete and activated saccharomycete by the theory of Langmuir . Then , we compared the efficiency of them and applied them to work on the waste liquid in industry.

稀子蕨的生殖策略探討

稀子蕨(Monachosorum henryi Christ)生長在台灣中海拔山區,是少數具有特殊生殖方式(不定芽)的蕨類。本研究對東眼山的稀子蕨族群進行物候調查,以了解其進行孢子繁殖及不定芽繁殖的過程,並試圖探討稀子蕨的不定芽是否可增加其族群對環境的適應性。研究結果顯示稀子蕨的孢子體及原葉體都無法在乾旱的環境下生存,常有大規模乾死的現象;而其不定芽則具有很強的耐旱性,無論是在季節普遍性及幼苖發育程度上,生殖芽都比孢子繁殖較佔優勢。而且其不定芽於旱季結束後,可迅速萌發,長出的孢子葉可隨之進行有性(孢子)及無性(不定芽)生殖,使其族群不至於在旱季中有地區性滅絕之虞。;Monachosorum henryi Christ , which exists in the middle elevations of the mountainous regions of Taiwan, is a fern with a special reproductive system seldom found in other ferns.This study investigates the phenology of Monachosorum henryi population in the Don Yang mountain region. Its purpose is to understand the sexual and asexual reproductive cycles of these ferns and to interpret whether or not the buds can increase the fitness of their population during the dry season.The results show that it is extremely difficult for the sporophyte and prothallus of Monachosorum henryi to survive in a drought. However, the buds have a much stronger drought endurance. According to this investigation, the adventitious buds of Monachosorum henryi are superior to the spores in seedling development in every season. Adventitious buds are able to germinate soon after the dry season as well as in any other season, and are able to grow spores and buds on their fronds enabling both a sexual and asexual way of proliferation. In this way the fern avoids a district extinction of their population.

The role of miRNAs in plant development and virus defense

微型RNA是最近發現的小RNA,調控生物體內的反應,包括生長、細胞分化、對抗病毒…等。植物利用RNA干擾 (RNAi) 或過敏反應 (HR) 對抗病毒感染。有趣的是,miR168可藉由降解mRNA或抑制轉譯,調控阿拉伯芥AGO1的表達,而AGO1是RNAi的一個重要元件。miR398則調控銅鋅超氧化物歧化? (CSD1, CSD2) 的表達,而CSD1, CSD2負責產生過氧化氫去引發細胞凋亡 (cell apoptosis)。帶有竹嵌紋病毒 (BaMV) 全長基因的轉殖菸草 (Nicotiana benthamiana) 品系27-17是我們的研究材料。27-17的幼葉不具病徵,隨著葉子的生長,病徵會漸漸變嚴重。我發現被病毒感染時,植物會提高AGO1的表達,使RNAi更有效率。然而,病毒藉提高miR168使AGO1的量無法上升。植物亦可提高CSD1, 2 mRNA的量,促進細胞凋亡。病毒卻會引發miR398降解CSD2 mRNA。在病毒力價高的葉子中,雖然CSD2 mRNA降低且miR398升高,植物仍可大量提高CSD2蛋白的量。CSD1 mRNA沒有被miR398負調控,詳細原因仍有待研究。

碳黑受閃光產生爆鳴聲之研究

紙杯底部用蠟燭燻出碳黑,經數位相機閃光拍攝後會聽到爆鳴聲。探討的結果為爆鳴聲是由相機的閃光與碳黑之間的互動所引起,甚且到冒煙程度。\r 探討結果得到爆鳴聲大小會受電場、溼度的影響而且碳黑量愈多,電子傳遞路徑會縮短、導電性則增高,且與產生的電量接近線性關係。\r 發現波長較短的可見光可形成較多的電荷;若照度大、受照射面積大或碳黑的粒徑小,這些會產生較多的電量。\r 經由電顯及AFM圖可知去漬油、蠟燭、瓦斯、95汽油、酒精燃燒後產生的碳黑,大小範圍都是在30nm~100nm範圍內。將蠟燭碳黑接受不同次數的閃光後,看出表面碳粒會變成灰燼。

圓來如此─西姆松「圓」的研究

若從一個三角形的外接圓上取一點,作其對三角形三邊的垂足,我們知道這三點共線,是為西姆松線。\r 那麼當此點不在圓周上的情形呢?自平面上一點對一三角形的三邊分別做垂線,得到三垂足,並作此三垂足的外接圓,我定義其為:此點對此三角形的西姆松圓。這篇作品主要成果便是對西姆松圓的研究。透過不斷的研究,發現了許多關於西姆松圓的神奇性質,並得到了一些結果,主要的研究方向:討論共點、共圓、相似。\r 這篇報告是循序漸進的,後面的結果常用到前面的知識為基礎。此篇另一特點是:全篇的證明皆是自已給出的,採用方法皆為一般幾何證明,而沒有用到解析證明。\r 在研究過程中也得到關於著名的費爾巴哈定理及大上茂喬定理的另一種證明。

極速骨牌-骨牌終端速度及鏈鎖反應機制之探討

本研究主要在探討骨牌脈波在傳遞時的速度變化,並比較在不同的骨牌和不同的排列方式下骨牌的終端速度有何種差異;同時也研究骨牌在鏈鎖反應下能量的放大現象。觀察後發現單列骨牌脈波在傳遞一段距離後,由於空氣阻力的影響,脈波將會達到一終端速度,此終端速度與骨牌高度成反比,而與骨牌質量平方成正比。骨牌的脈波傳遞在鏈鎖反應下仍有一終端速度,但大於單列之骨牌脈波速,且鏈鎖反應具有放大推力之功能。由我們的研究可預測一列物體傾倒時所花費時間和所能達到之終端速度,而鏈鎖反應可比擬為一雷射模型能量集中和釋放的機制,相信可利用骨牌儲存能量的機制應用於需迅速釋能的機械中 This research is mainly discussing the changing of velocity of a domino pulse, and comparing the terminal velocity of various kinds of dominos and arresting modules. Also we focus on the energy-enlarging fact of chain-reaction of domino series. We found that after running a distance, the pulse of a single-series domino will finally reach a terminal velocity by the friction force of air. The terminal velocity will inversely proportion to the height of a single domino, and will proportion to the square of mass of a single domino. During a chain-reaction, the pulse still has a terminal velocity, but it is higher than the terminal velocity of a single series domino .The chain-reaction has an ability to enlarge the original force, too. By the research, we are able to predict the time interval and the terminal velocity while a series of objects are falling. On the other hand, the chain reaction is similar with mechanism of energy concentration and emission of LASER. We also believe that this mechanism is able to explain and apply to those machines which need to release energy rapidly.

核醣核酸蛋白粒之K 蛋白基因表現及功能之研究

核糖核酸蛋白粒之K 蛋白具有多種功能,可參與在基因轉錄和蛋白質轉譯等過程。我們發現\r 一新奇的cDNA 較已報告的K 蛋白cDNA 少了72 個核?酸,分別命名為S 形與L 形。由基因\r 組DNA 的分析,S 形可能是經由替代剪接少了第8 個exon 所形成。以西方墨點法分析細胞中\r 的K 蛋白,亦證明有S 形存在,其表現量較少且多存在於細胞核中。為了探究兩種K 蛋白等\r 形的表現和功能,我們以PCR 偵測K 蛋白在不同組織與細胞株和人類乳腺腫瘤組織中的RNA\r 表現,結果顯示主要以L 形為主;我們並將S 形與L 形K 蛋白分別轉染至人類乳癌細胞株MCF7\r 中,以抗生素篩選出穩定表現K 蛋白之細胞株,生長速率分析顯示表現S 形之細胞株生長速\r 率較慢,其分子機轉仍有待研究。另外在比對K 蛋白之基因組DNA 時,除了在第九對色體\r 上有完整之K 蛋白基因組DNA,我們亦發現在第2、3、5 及11 對染色體上有類似K 蛋白基\r 因的序列,以cDNA 的形式存在,這些DNA 序列是否可以表現RNA 及其意義為何,目前尚\r 不清楚。Heterogeneous nuclear ribonucleoprotein K (hnRNP K) is a multifunctional protein known to be\r involved in the regulation of transcription, translation, nuclear transport and signal transduction. We\r have identified an alternative splicing transcript of hnRNP K lacking exon 8. This novel isoform\r (named S form compares to L form of full-length hnRNP K) encodes a protein that is 24 amino acids\r depletion between RNA binding KH1 and KH2 domain. To explore the functional roles of both isoforms,\r we detect their expression in several tissues (including liver, lung, kidney and heart), cell lines (MCF7,\r 293T, HeLa, NIH3T3, WEHI, P388D1) and specimens of human mammary gland tumor by RT- PCR.\r The results showed that L form was expressed in all samples, whereas S form was only expressed in cell\r lines. Using Western blotting analysis, we found that L form existed in both cytosol and nuclear\r fractions, and little amount of S form was detected in the nuclear extract. Furthermore, we construct the\r MCF7 cell lines that stably expressed S form or L form hnRNP K. Growth rate analysis indicates that\r the overexpression of S form of hnRNP K could decrease cell growth rate. The molecular mechanisms\r of growth inhibition by S form hnRNP K are to be further investigated. On the other hand, when we\r blast the human genomic genebank, we found except the chromosome 9 containing complete hnRNP K\r genomic DNA, there are near complete hnRNP K cDNA sequence appears in chromosome 2, 3, 5, and 11.\r The meaning of these sequences is unclear.

磁流體的浪潮-磁場梯度下磁流波紋之研究

在本次實驗中,我們發現在不同厚度的磁流體薄膜中,會因本身磁性粒子結合,而呈現不同的影像圖形。隨著薄膜厚度增加,其磁性粒子會由鏈狀排列成塊狀叢集,可是一旦外加磁場後,又要全部轉向磁力線方向集結。另一個發現是將磁流體薄膜放在一個不均勻的磁場梯度中,則樣品內的磁流體粒子,不僅會隨著磁力線的方向排列移動,更會出現磁流波紋,其行進路徑是沿著垂直於磁力線的方向,向磁力線密集處移動。我們亦發現在不同的薄膜厚度及不同外加磁場下,其”磁流波紋”的波速亦會隨之改變。一般而言,樣品的厚度愈厚,或外加磁場愈大,其”磁流波紋”的波速愈快,反之則愈慢。最後,我們列出了一些磁流波紋的應用,相信是精采可期!In this experiment, we find that in different thickness of magnetic fluid different images will appear, because of the connection of magnetic particles. With the increasing of thickness the magnetic particles will change its shape from chains to blocks. But when we add external magnetic field, they will get in line one by one to the direction of magnetic line of force. We also find that we put the magnetic fluid film in the uneven magnetic gradient, the magnetic particle in the sample not only follow the direction of magnetic line of force but also show the “magnetic wave”. Its move path is perpendicular to the direction of magnetic line of force. In the different film thickness of magnetic field, the wave velocity of the “magnetic wave” will change. In generally, the thicker the sample is, or the larger the magnetic field is, the faster the wave velocity of magnetic wave is and adverse is true. At last, we list the applications of “magnetic wave”, we believe they are marvelous!

廣鹽性吳郭魚氯離子調節機制- - - NKCC在氯細胞中扮演之角色

本實驗中我們利用廣鹽性吳郭魚進行氯離子調節機制的研究,探討廣鹽性吳郭魚如何能在不同環境中維持體內氯離子恆定,進而適應生存環境。我門想要探討:『是否NKCC 這種蛋白質在淡水吳郭魚MR 細胞中扮演吸收 Cl- 的角色? 如果是,吳郭魚又如何藉NKCC 的調節適應環境中 Cl- 的變化呢?』我們利用細胞免疫螢光染色法、西方墨點法和共軛焦顯微鏡觀察分析NKCC 在不同 Cl- 濃度人工淡水馴養的吳郭魚MR 細胞上的表現量,結果發現 NKCC 分布於頂端細胞膜(又稱為細胞開口),及其附近的細胞質內;環境中 Na+ 濃度的差異對NKCC 在MR 細胞上的表現影響不大,但低 Cl- 環境馴養的吳郭魚,NKCC 表現量都高出其他組很多。顯示NKCC 參與了氯吸收的機制。另一個實驗中,我們將吳郭魚由淡水中轉移至海水以分析它們在適應海水的過程中NKCC 的表現變化。結果發現在馴養初期(16 小時內),圓點狀NKCC 仍然可以在MR 細胞的開口附近觀察到,但到了24 小時後,NKCC 在開口的表現就明顯減少甚至消失,取而代之的是轉移到底側邊細胞膜上的NKCC。此實驗證實了NKCC 這一個與Cl-運送相關的蛋白質,在廣鹽性吳郭魚氯離子調節中扮演了很重要的角色。 Euryhaline tilapia (Oreochromis mossambicus) is capable of maintaining internal ion constant ineither hypertonic or hypotonic environments (fresh water or seawater).MR cells in the gills of tilapia play critical role in absorbing Cl- from fresh water or pumping redundant Cl- from body fluid into seawater. Chloride transporter (NKCC) which distributed in basolateral membrane of MR cells is involved in Cl- secretion of seawater teleost. However, the mechanism of Cl- absorption in fresh water MR cells is still unclear. Whether NKCC is also involved in Cl- absorption and how do tilapia regulate Cl- absorption are the questions this study aim to answer. By using immunofluorescent staining, western blot, and confocal microscopy, the distribution and expression level of NKCC in fresh water MR cells were examined. We found that NKCC is distributed on the apical membrane of freshwater MR cells where is known to be the site for active Cl- absorption of MR cells. We compared the expression level of NKCC in MR cells from tilapia acclimated in high, normal, and low Cl- artificial water for 7 days. The results showed that NKCC is induced by ambient low Cl- , and in contrast suppressed by high Cl- water, indicating NKCC might be involved in Cl- absorption of freshwater MR cells and up-or down-regulated to maintain Cl- uptake constant. In addition, we also examine the expression pattern of NKCC in MR cells from tilapia transferred from fresh water to seawater. Confocal images show that apical expressed NKCC disappear gradually within 24h seawater acclimation and is substituted by basolateral expressed NKCC. This study provides a novel regulatory mechanism of NKCC in Cl- transporter of MR cells.