全國中小學科展

四等獎

雙叉桿菌於不同優酪乳中抗氧化性之研究

The objectives of this investigation were to evaluate the growth conditions and the antioxidant activities of fermented black bean soy milk(BBSM) with Bifidobacterium longum B6 and 15708 cultured in four media, namely, ( BBSM ( 100%)+ 1% glucose ), ( BBSM (100%)), ( BBSM (50%) + milk (50%)), (milk (100%)) . These results indicated that; (1) both strains attained viable cell numbers about 7.19~9.53 log CFU/ml after 18 hrs of incubation and were in the order of ( milk (100%))>( BBSM (50%) + milk (50%))> ( BBSM (100%) + 1% glucose)>( BBSM (100%)), (2) both strains in ( BBSM (100%)) exhibited higher pH value ranging from 4.79 to 5.50 , but lower titratable acidity(%) ranging from 0.27% to 0.61% than the three other media after 48h of fermentation, (3) both strains displayed an even smaller tolerance to simulated gastric juice at pH = 2.0 for 3h, especially in ( BBSM(100%)), while in simulated gastric juice at pH =3.0 for 3h had higher tolerance , (4) both strains had high resistance ranging from 72.51% to 92.62% to 0.3% bile solution for 12h, (5) the reducing power of ( BBSM (100%)) was more excellent than that of ( milk (100%)), (6) the scavenging effect of yogurt (BBSM ( 100%) + 1% glucose) on DPPH radicals was significantly higher than that of ( milk (100%)), (7) In general, at ten- fold dilution the chelating effect on copper ions of these four un-fermented media except ( milk (100%)) was significantly higher than that of fermented media with B.longum B6 or 15708. 本研究是探討雙叉桿菌(Bifidobacterium longum B6及15708)在四種發酵基質(【黑豆奶(100%)+1%葡萄糖】、【黑豆奶(100%)】、【黑豆奶(50%)+牛奶(50%)】、【牛奶(100%)】)中的生長情形及抗氧化活性。結果顯示: (一) 兩株菌在四種培養基中的生長菌數大小順序如下:【牛奶(100%)】>【黑豆奶(50%)+牛奶(50%)】>【黑豆奶(100%)+1%葡萄糖】>【黑豆奶(100%)】。 (二) 兩株菌在【黑豆奶(100%)】的pH值比較高於其他三種優酪乳,而最終發酵可滴定酸度比較低於其他三種優酪乳。(三) 兩株菌於pH2.0環境下,在【黑豆奶(100%)】優酪乳中耐酸性很低,而於pH3.0環境下卻有很高的耐酸性。(四) 兩株菌對0.3%膽鹽之耐受性均很高為72.52%~92.62%。(五) 在稀釋10倍的四種基質中,不論發酵前或發酵後的還原力皆以【黑豆奶(100%)】為最高,【牛奶(100%)】為最低。(六) 在濃度稀釋10倍時,【黑豆奶(100%)+1%葡萄糖】對DPPH‧自由基清除率明顯比【牛奶(100%)】高。(七) 在濃度稀釋10倍的四種優酪乳中,除【牛奶(100%)】外,發酵後比未發酵的銅離子螯合率明顯降低。

探討第三號誘餌受體對NOD小鼠糖尿病預防與T細胞分化影響之研究

DcR3是腫瘤壞死因子6B的成員(Tumor necrosis factor receptor superfamily),又稱為TR6或M68。DcR3會藉由與Fas Ligand, LIGHT或TL1A等細胞表面配位結合,阻擋T細胞的死亡訊息傳輸,保護該細胞免於細胞凋亡;另外,DcR3也會與抗原呈現細胞的硫化肝素糖蛋白結合,誘導未分化之T細胞發育成能減少自體免疫疾病發生的Th2細胞,顯示DcR3有充分作為自體免疫疾病預防之藥物的可能性。因此我藉本實驗探討DcR3對T細胞分化與發育造成的影響與造成此一現象的原因。 根據實驗結果,我們發現DcR3不僅有上述之功能,更能增加調節型T細胞(Treg)這種抑制免疫反應的特殊T細胞表現量,若能藉由Treg調控免疫系統活力,將可改善易般免疫抑制劑治療造成病人免疫力下降之缺點。因此我藉由NOD小鼠,實際檢測DcR3在活體中對抗自體免疫疾病發生的能力,並以DcR3與T 細胞之交互作用實驗,探討現象的成因。根據實驗結果,在Somatic gene therapy和Protein therapy的實驗中,皆可看出疾病延遲發生的現象。而在DcR3對T細胞存活率的影響方面,可看出DcR3並不會造成T細胞之異常死亡。故我們推測DcR3可藉由增加Treg表現量減緩或降低NOD小鼠糖尿病的發病。 因此我們認為DcR3非常有潛力作為未來自體免疫疾病預防或移植手術後用以抗排斥之藥物。

漂浮的油滴--CMC 的測定

Surfactants have a great effect on decreasing the surface tension in aqueous solution and thus they are important components in detergents. The present study aims to explore the cleaning mechanisms of the substances for greasy subjects such as bowls and clothes. The roles of various surfactants that have on the changes in the surface tension of aqueous solution in the presence and absence of additives such as tea and salt have been carefully studied by using a lab-made equipment. We carefully observed the changes in the oil droplets after pushing oil in a syringe to the aqueous\r solution containing surfactants and additives. With decreasing the surface tension of the aqueous solution, the size of the droplet becomes smaller. By using this simple lab-made equipment, we are able to determine the critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS), with a result of 0.0079 M at 20 ℃. The result is in a good agreement with the literature (0.0077M). With decreasing temperature and adding salts such as sodium sulfate, the decreases in the surface tension have been confirmed by our simple experiments. This simple equipment also allows study of the effects of impure additives such as salt, tea, vinegar that have on the changes in the surface tension of aqueous solution containing commercial detergents. We have found that most of the additives have a great effect on reducing the surface tension of the aqueous solution. The present study results suggest that the simple experimental set-up is practical for measuring the CMC of surfactants and for exploring the effects of additives on changes in the cleaning ability of commercial detergents.界面活劑性可有效降低水溶液的表面張力,因此,他們是清潔劑的重要成份。該實驗主\r 要在探討各種物質的清潔機制。利用自製的實驗裝置,針對各種不同的界面活性劑在添加了鹽類或茶水後界面張力的改變量,作詳盡的探討。我們將含有不同濃度界面活性劑以及添加物的水溶液裝入容器中,在推擠針筒使其的油通過針頭並進入該溶液後,我們仔細的觀察紀錄油滴大小的改變。結果顯示界面張力的降低會使得油滴變小。藉這個自製的裝置,在20℃下,本實驗所測得的陰離子型界面活性劑-十二烷基硫酸鈉之臨界微胞濃度0.0079M。結果幾乎與過去的文獻0.0077M 值符合。該實驗同時也證實了降低溫度,添加了鹽類後,可有效的降低界面張力。此外,此實驗裝置也可以用來測量市面上販售的清潔劑在添加了不純的物質後,其界面張力的改變量。我們發現大多數的添加物都能有效降低界面張力。目前的實驗結果顯示,這項實驗裝置在測定臨界微胞上有很高的實用性,同時也可以探討不同的添加物對市面上販售的清潔劑之洗淨力的影響。

水滴奇遇記-蓮花效應的真面目

Lotus self-cleaning effect arises because the leaves have the superhydrophobic surfaces. When rain falls onto a lotus leaf, water beads up as a result of surface tension. The water drops promptly roll off the surface, taking every dirt with them. This phenomenon is called the lotus effect. With the aid of a light microscope and an Environmental Scanning Electron Microscope, we observe and describe the morphology of the leaves of Nelumbo nucifera in detail. We successfully observe the real interface between air, water droplets and the papillae of a lotus leaf, and find the evidence of a composite surface that is formed by epicuticular wax crystals and air. These observations improve our understanding of the two-level composite surfaces that are formed by micro-scale papillae, nano-scale epicuticular wax crystals and air. We try the method of using the critical angle of a static drop beginning to roll on inclined surface to evaluate the self-cleaning ability. We then find out that it may be a more precise criterion compared to using the static contact angle for the evaluation of the lotus effect. Literature review shows that the earlier investigation lacks the height(H) and interval(I) of the projections on the lotus leaf surface. A close relationship between the self-cleaning property and the H/I ratio is found. In this study, we present the experimental data of the height and interval of the projections on four different species of plant leaves that all have lotus effect, which may be of great help to technological applications. 蓮花效應是指蓮葉表面具有超疏水性與自我潔淨的能力,當雨水落在葉面,因為表面張力的作用形成水珠,水滴迅速滾離葉面,把灰塵一起帶走。本實驗以光學顯微鏡和環境式掃描式電子顯微鏡觀察蓮葉,詳細描述其表面形態,成功的發現空氣、水滴和蓮葉乳突真實的接觸界面以及表面蠟和空氣構成複合表面的證據。實驗結果可以使乳突、奈米表面臘質和空氣構成的雙層次複合表面更容易被了解。我們嘗試以水滴傾斜滾動臨界角來評估自潔能力強弱,實驗結果比傳統使用靜止接觸角更為準確。表面高度和間距的比值與蓮花效應有很大的關係,查閱文獻顯示蓮葉缺乏這些資料,本研究提出四種有自潔能力的葉子的實驗數據,這些數據應該對科技應用有很大的幫助。

蟹狀星雲的擴張

By comparing eight different epoch images of the crab nebula taken through 1942 to 2004, we have calculated the expansion velocity of 27 optical bubble features and 60 filaments. The mean expansion velocity of bubble features and filaments is 0.173 arcsec/yr and 0.15 arcsec/yr, respectively. We also estimated the maximum radial velocity of the expansion by analyzing the emission spectrum of the nebula. The maximum radial velocity is 1385.5 km/s. Combining these measurements indicates that the crab nebular is approximately 5870 light year away. In addition, if we assume that the nebula has been expanding at a constant rate, our expansion velocity projected backward indicates the mean date of the supernova event as A.D 1124, more than 70 yrs later than the accepted date of 1054. The result confirms the well-known acceleration in the crab's expansion. Although we have analyzed eight images with a 62 yr baseline, the acceleration still can't be derived from this study. 透過量測由1942年到2004年之間八張不同年代的蟹狀星雲中爆炸後殘骸的位置變化,可以計算出蟹狀星雲爆發的擴張速度。本研究選定了27個包狀物和60個纖狀物,計算出的擴張速度分別為0.173 arcsec/yr.和0.150 arcsec/yr。再透過分析蟹狀星雲的光譜所計算出的徑向速度(radial velocity)為1385.5 km/yr,進而推得蟹狀星雲的距離分別為5430光年和6370光年,平均值為5870光年。 另外,如果假設擴張速度是等速運動,那麼把求得的擴張速度倒推出的爆發日期是在西元1124年,這比中國紀錄中超新星爆發的1054年晚了70年。這顯示出蟹狀星雲的確非等速擴張而是有加速度的狀態,才會造成以等速倒推發生日期時,晚了70年。雖然本研究中分析了相差62年之久的八張影像,仍然無法分析出星雲的擴張的加速度情形。

奈米碳管的成長機制與電性量測之研究

本實驗是控制奈米碳管的成長條件,研究奈米碳管的成長機制、電子場發射特性。奈米碳管的物理性質會因捲曲度(helicity)、管壁厚度(單層或多層)、管徑所影響,而不同的捲曲度,會形成不同電性(金屬性或半導體性)的奈米碳管。由此可知,探討奈米碳管的成長機制,以控制奈米碳管的穩定成長,及如何長出電性或光學性質相近的奈米碳管,是極為重要之事。為了研究奈米碳管的成長機制,我們使用微波電漿輔助化學氣相沈積法 (Microwave plasma ehanced chemical vapor deposition) ,在市售的縫衣針針尖上,成長奈米碳管,這個技術能夠經由吸收微波達到局部加熱針尖的方式,再透過控制微波功率、通入氣體的種類、壓力的變化以及催化劑的使用,能夠達到有效控制奈米碳管的成長條件。我們改變三個參數:催化劑的使用、氣體種類(Ar+CH4 或N2+CH4)及壓力,之後利用SEM 觀察奈米碳管的成長情形;再測量場發射(測量電性),討論不同成長的條件與場發射電流關係。

Applied Red Palm Weevil Farming

The Red Palm Weevil is a kind of pest commonly found in all coconut and palm growing areas, causing considerable damage to palm trees. The pest at larva stage was found to be a popular food dish for both local people and visitors and has been commercially bred for consumption. This project aimed to develop a farming method to increase the quantity of red palm weevil larvae for commercial use, instead of the natural farming which fed the insects on rare natural materials. Firstly, the most appropriate food formula to boost the multiplication of red palm weevil using local raw materials was determined. Four food formula were developed: 1.combination of palm leaves, coconut fibers, and pig food, 2.palm leaves, coconut fibers, and rice bran,3. palm leaves, coconut fibers and cassava,4. a combination of crushed palm leaves and coconut fibers. The mixture ration were 1:1:1 for formula1-3 and 1:1 for formula 4. Equal number of the adult weevils were raised in the different food formula, the length and weight of the larvae obtained were measured every week for seven weeks. The gross weights and the effectiveness of the red palm weevil farming were analyzed using the feed conversion ratio (fcr), the daily growth rate, and the percentage increase in weight. It was found that. the weevils raised with food formula 1 yielded the larvae which grew the fastest with highest effectiveness. The most appropriate ratio of the food mix which yielded the satisfactory larvae size was determined to be 1:1:1 3.Next, experiment was carried out to improve the quality of the insect larvae for consumption. The larvae produced had some distinct smell which some consumers do not like.To improve the smell, the larvae were fed with the selected food mix added with minced fresh Pandanus leaves 2 days prior to consumption. Food mix with coconut fibers instead of Pandanus were used as control. Consumers were most satisfied with the larvae fed with added Pandanus leaves. Analysis of the food mix, larvae and Pandanus leaves found the common compound, Coumarins. In conclusion, our project found a suitable system of red palm weevil farming an alternative to conventional method which farmed the pest on cut palm trees. The new method resulted in the best yield of insect larvae with the highest consumer satisfaction and reduce destroying natural resource.

綠色化學-應用吸水高分子螯合銀離子並製成奈米銀

聚丙烯酸(PAA)是尿布中吸水成份,我們利用其結構上的羧基螯合Ag+,並成功以甲醛將Ag+還原成奈米銀。但我們意外發現螯合Ag+的PAA白色粉末在沒有其他還原劑存在下也會漸漸變成黃色,與「利用甲醛還原製得的奈米銀」顏色十分相似。本實驗即揭開此粉末變色真相,希望能在不使用額外還原劑下,直接以PAA將螯合的Ag+製成奈米銀,不僅具環保與實用價值,更能使奈米銀製程朝向綠色化學。我們透過水溶性聚丙烯酸鈉(SPA)在均相中進行變色機制探討及影響變因的研究,找出有利的反應條件,再應用於PAA。研究證實PAA能將螯合的Ag+同步還原成奈米銀,反應機制與檸檬酸鈉作用模式相似,而提升濃度、溫度或照光有利於反應,酸性條件則不利,照各種色光也有所差異。

Self Assembly Mechanism of Water Droplets

這是一系列關於水蒸氣冷凝為極細微水珠的實驗。其中可以歸納為三大部分,第一部分是基礎實驗,將水蒸氣導引至親水性介面上,觀察冷凝水珠的結構。雖然看似簡單平常,但是卻發現:不同溫度的水蒸氣,其冷凝最初始的細微珠粒,尺寸相同;爾後溫度高者,堆疊速率較大,以至於最後同時呈現的水珠大小不一,尺寸不同! 第二部分,是針對冷凝水珠自我組裝機制的探討。實驗是將水蒸氣導引至密度小於1的高分子溶液上,並藉由揮發性溶劑快速揮發,將水珠粒「分層保留」以便更深入了解「解構」後的水珠群聚機制。在這組實驗中得到兩張有趣的圖片: 在討論時,我是從對流機制切入,嘗試解構上面兩張圖。 第三部分的實驗,是將水蒸氣導引到磁場及靜電場上,觀察冷凝的機構。這部分呈現出來的結果,推翻了一般「水分子為電中性應該在電場與磁場中不受影響?」刻板觀念,實驗呈現水分子:不但在電磁場上不易長大同時也有固定的散佈模式(assembly pattern)。同時也觀察到:水分子在正電場形成的凝結水珠較為均勻,在負電場則表現出較大親水性特質。這部分的實驗對日後研究細胞膜上水分子通道應有助益。 I have tried to ask a famous math professor if he can create a formula describing the ordered array of water droplets. “Then, I should study Physics first!” He said. Condensation is the thing we live with, being found everywhere, passing without notice. But we never know when it dose start? By coalescence, water droplets grow bigger, but are not round again. We used the polymer film as template and designed the solution lighter than water, so the minute droplets will sink to the bottom and layer by layer. After seconds we may have multilayers of ordered array. This experiment presented here is actually the diary of the growth of water droplets through condensation, upon volatile fluid, magnetic field and electric field. Through convection, it discusses the self assembly mechanism of water droplets and peep into the uniformity of the size of water droplets. In this experiment, convection and magneto-electric force did play important roles in the self assembly mechanism of water droplets. The topic is mostly concerned as we are surrounded by magneto-electric waves in today’s world. This is the first step in discovering the homogeneous state of water droplets, providing insights into the self assembly mechanism of water droplets with nano sizes.

Equipping, programming and testing a robot searching for an avalanche transceiver

1. Purpose of the research Because we live in a famous winter sport region in Switzerland, we have been confronted with the problematic of avalanches since we were born. In winter 2011/2012 alone, 179 people were involved in an avalanche accident, of whom 25 died. The most important device for searching and rescuing a buried person is the avalanche transceiver. It creates an electromagnetic field, which can be used to locate a buried person with another transceiver. The most important factor while searching is time: After 30 min. the chance of survival of a buried person has dropped to 40%. Considering the fact that people often make mistakes when they are put under such a big stress, valuable time gets lost. This is where our project comes into play. With an automation of the searching process a fast and reliable search should be achieved. The aim we agreed on for this paper is to develop a prototype of a robot that can find an avalanche transceiver automatically and reliably. To study and optimize the functionality of our robot more easily, our tests have only been performed on flat ground. 2. Procedures The components of an avalanche transceiver with only one transmitting antenna are used as a receiver. With the help of this receiver, the signal of a transmitting avalanche transceiver was analysed. Furthermore, the results were used to evaluate the most suitable search technique. Our robot is based on the “RP6” robot system, which is programmable in the C-language. The signal of the receiver is modified in a way which allows the robot to read it. Based on the results of the signal analysis, a search algorithm is developed. In the final tests the robot was examined as to its functionality and efficiency. Therefore, the robot was positioned at randomly chosen starting points to locate the transmitting device. 3. Data The transmitter could be located correctly in every test. The starting points were successfully located up to 11 m from the transmitter. The search ending points were found at a maximum range of 0.5 m from the correct position. 4. Conclusions In view of the results, the aim of developing an automatic localisation of an avalanche transceiver on flat ground as a prototype is seen as fulfilled. Outside the specified range, the transmitter can only be located unreliably. This is due to the fact that outside that range the signal differential in different directions is too small to be processed by the robot. Our prototype was tested under ideal conditions. Certainly, our robot is still some way from being ready for use in an actual avalanche. Many different questions have not been answered yet or have come up during this project, for example: ‘How should the robot should be applied on uneven terrain?’ or: ‘How should it deal with several buried people at once (multiple transmitted signals)?’ Two aspects of our prototype, the low weight and the low construction costs, however, are particularly favourable.