全國中小學科展

2002年

快速檢定抗生素對細菌生物膜敏感性之新技術

The purpose of this study is to set up a quick, easy and economical way to evaluate the ability of different concentration of various antibiotics to penetrate biofilm and establish the antimicrobial susceptibility patterns of various antibiotics. The susceptibility of five antibiotics upon sessile cultures of Bacillus subtlis ATCC 6633, Escherichia coli XL, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213 and Sarcina lutea ATCC 9341 were measured ATCC 27853, and S. aureus ATCC 29213 proved to be very difficult to eradicate, with only Gentamicin proving to effective at achievable drug concentrations, but the S. lutea ATCC 9341 biofilm was the most susceptible to the Penicillin. The results demonstrated that for biofilms of the same organisms, several hundred to thousand times the concentration of a certain antibiotic were often required for the antibiotic to be effect, while other antibiotics were found to be effective at the MICs. The concentration of antibiotic to penetrate the biofilm is proportional to the thickness of biofilm. Indeed, our research have already indicated that the use of MIC values to indicate antibiotics effectiveness is misleading, because MIC values can not represent the actual effect of anticbiotics on microbiologicals that have developed biofilm. The antimicrobial susceptibility patterns of antibiotics to various bacterial biofilm are different. The susceptibility of the mixed biofilm depends on the physical and biological change of biofilm. Our biofilm device offers a new technology for the rational evaluation of antibiotics effective against microbial biofilms and for the screening of new effective antibiotic drugs.此研究之目的是要建立一套操作簡便、快速且費用低廉之生物膜厚度產生方法,藉此探討不同生物膜厚度對抗生素抗菌之影響,進而完成抗生素對生物模之抗菌圖譜。本實驗將測試五種抗生素Bacillus subtilis ATCC6633,Escherichia coli XL,Pseudomonas aeruginosa ATCC27853,Staphylococcus aureus ATCC29213和Sarcina lutea ATCC9341之抗菌圖譜。試驗結果顯示Gentamicin對前四株試菌有較佳之穿透力,對S.lutea ATCC 9341則是Penicillin。實驗結果證明最小抑制濃度值確實無法實際有效地表達對已形成生物膜菌體之抗菌效果,要完全去除生物膜之抗生素濃度是為最小抑制濃度之數百倍到數千倍,而且抗生素用藥濃度隨著生物膜厚度增加而成比例增加。不同抗生素對不同菌株生物膜有不同之抗菌圖譜,混合菌株生物膜是否會促進或抑制抗生素之穿透力,端視其生物膜結構有無改變。本實驗方法可以做為一種快速檢定抗生素對細菌生物膜敏感性之新技術,同時亦可有效地篩選新的抗生素藥物對生物膜的抗菌效應。

颱風遇到山~談地形對侵臺颱風風速.雨量的影響

去年(民國九十年),我們在國中地科課本第六章「多變的天氣」中看到一段不懂的話:「颱風移到高緯度的海面以後,也會因低層水氣的供應變少變弱消失。」(104頁第二行)請教老師之後,疑惑未解。師長們幾番鼓勵之後,我們這群對大氣現象原本就充滿無限好奇的國中生便想試試能否一探問題真相,想到能夠挑戰學生心目中至高無上的課本,我們真的是非常興奮!\r 經過數週的資料蒐尋與交叉討論之後,我們發現這並不是件容易的事,事情並非我們想的那麼簡單。於是,在大家冷靜沉澱 想法之後,我們便把焦點放在颱風與地形的交互作用上,先從難度較低的項目開始學習。

大自然的奧妙~土壤自我淨化能力

大氣圈、水圈與土壤圈是構成自然環境的三大領域,三者之間相互的影響,原本這些空間都具有極大的包容力,亦所謂「自淨能力」,許多的物質進入其中皆會被氧化分解或稀釋而消失於無形。近年來由於工業發展、人口增加,產生大量的廢棄物,長期、密集且迅速的堆積於環境中,使得天然的自淨能力無法應付而失去功能,造成嚴重的後果。就土壤而言,雖有較佳的自淨能力,但是一受污染,除了嚴重破壞土壤品質之外,同時也會直接或間接污染水源 (如:地下水)及空氣,對動植物造成危害,並且難以回復,實不容忽視。本實驗探討:一、土壤淨化能力是否受到不同地區、不同土壤性質的影響。二、同樣的土壤,對不同的污染物(色素、肥料、重金屬)淨化能力強弱的影響。實驗結果顯示大肚山土壤過濾溶液中的色素、磷、及重金屬中的鉻、鎳、銅的能力較中寮及大甲土壤強,只有氮與鉀的過濾能力較大甲土壤差,所以這次實驗中大肚山土壤有最好的污染淨化能力。實驗結果將來也許可以應用於土壤處理場址之適宜性評估。The air, water and soil are three parts of the nature. They affect each other. In fact, they have the "self-purity ability" - they can disassemble many polluted thing by this kind of self-purity ability. These years, because the industry development and the population explosion make lots of waste, the self-purity ability cannot do its best. The soil has better self-purity ability, but if it is polluted, it will not only pollute the water (ex: underground water) and the air, but also damage the animals and plants. We cannot ignore the serious result. This experiment will discuss:1. If the soil self-purity ability is affected by different area and different soil specificity? 2. The different purified results according to the different pollutant (ex: color, fertilizer and heavy metal) in the same soil. Results showed that Da-Du-San soil had strong ability then Chung-Liao and Da-Cha soil in filtrated color, phosphor, chromium, nickel and copper in the solution, but had weak ability then Da-Cha soil in filtrated nitrogen and potassium. Therefore, Da-Du-San soil had the beast pollution-purity ability in this experiment. In the future, results may be applied to the suitability evoluation of the soil treatment place.

擬-Lucas多項式的幾個性質

本篇文章從"將aⁿ+bⁿ分解成(a+b)及ab的非線性組合"出發,在同樣的遞迴精神下引進並定義擬-Lucas多項式 <Sn (X)>:

三個新的鋅的幾何異構物

在本實驗中,我們合成了三個新的鋅的幾何異構物:trans-facial-[Zn(dipica)₂]Cl2.CH3OH(dipica=dipicolylamine,C12H13N3,雙(2吡啶甲基)胺)trans-facial-[Zn(dien)2]Cl2(dien=diethylenetriamine,C4H14N3,二乙基三胺)及反式-[Zn(demn)2Cl2](demn=N,N’-dimethylethylenediamineC4H12N2,N,N'-二甲基乙二胺)。本實驗的特色皆在室溫下反應,採用擴散法培養晶體。trans-facial-[Zn(dipica)22]Cl2.CH3OH晶體為三斜晶系,晶格常數a=8.8269(6)Å, b=8.9908(6)Å, c=10.0292(6)Å,α=76.715(1)。,β=81.232(1)。,γ=67.753(1)。;其空間群為P1,可信度R=0.025,Rw=0.0697。六配位的陽離子,其結構為扭曲八面體,兩個含氮三牙基(dipica)trans-facial配位,赤道面(ZnN(1)N(2)N(1A)N(2A))由兩個含吡啶環之氮(N(1)、N(1A))及兩個飽和胺之氮(N(2)、N(2A))所組成。主軸為兩個吡啶環之氮所組成。兩個含氮三牙基(dipica)與鋅的咬合角皆為84.5。。trans-facial-[Zn(dien)2]Cl2晶體為單斜晶系,晶格常數為a=11.3050(3)Å,b=10.9264(3)Å, c=12.6147(3)Å,β=92.884(1)。;其空間群為P21/c,可信度R=0.0191,Rw=0.0484。六配位的離子,其結構為扭曲八面體,兩個含氮三牙基(dien)與鋅的咬合角為156°、157°。反式-[Zn(dmen)2Cl2]晶體為單斜晶系,晶格常數 a=10.3397(4)Å,b=8.5916(4)Å,c=7.9774(3)Å,β=100.520(1)°;其空間群為C2/m,可信度R=0.0266,Rw=0.0686。其結構為八面體,鋅原子四個氮原子組成赤道面(ZnN(1)N(1A)N(1B)N(1C)),兩個氯原子位於此平面的兩側。兩個含氮雙牙基(dmen)與鋅的咬合角皆為83.0(1)Å。 In this study, we have synthesized three new geometrical isomers of zinc(II)complexes: trans-facial-bis(dipicolylamine)zinc(II)chloride-mathanol(1/2)(trans-fac-[Zn(dipica)2]Cl2.2CH3OH), trans-facial-bis(ethylenetriamine)zinc(II)chloride(trans-fac[Zn(dien)2]Cl2)and trans-bis(N, N'-dimethylethylenetriamine)zinc(II)chloride(trans-[Zn(dmen)2]Cl2). The crystals suitable for X-ray diffraction were obtained by slow diffusion of ether to solution of the products. There molecular strctures determined by X-ray diffraction. The complex trans-fac-[Zn(dipica)2]Cl2.2CH3OH crystallizes in the triclinic space group P 1 with a=8.8269(6)Å, b=8.9908(6)Å, c=10.0292(6)Å,α=76.715(1)。,β=81.232(1)。,γ= 67.753(1)。, for Z=1. The R value is 0.0259 for 3286 significant reflections. In the hexacoordinate cation, the two tridentate dipicolylamine ligands are trans-facially coordinated with two pyridine nitrogens and two secondary amine nitrogens situated on four positions in a basal plane(ZnN(1)N(2)N(1A)N(2A)). The remaining two pyridine nitrogens constitute the axis in a distorted octahedra structure. Colorless trans-fac-[Zn(dien)2]Cl2 crystallizes the monoclinic space group P21/c with a=11.3050(3)Å, b=10.9264(3)Å, c =12.6147(3)Å,β=92.884(1)。,and Z=1. The R value is 0.0191 for 3285 significant reflections. The zinc(II) atom has distorted octahedra coordination, in which the ligands are bound in a trans-facial configuration. Colorless trans-[Zn(dmen)2Cl2] crystallizes the monoclinic space group C2/m with a=10.3397(4)Å, b= 8.5916(4)Å, c=7.9774(3)Å,β=100.520(1)。, and Z=2. The R value is 0.0266 for 856 significant reflections. The zinc(II)atom of trans-[Zn(dmen)2Cl2]is six coordinate with 4 nitrogens of bidentate dmen forming a basal plane(ZnN(1)N(1B)N(1A)N(1C)),and two chlorines on the axial sites completing an octahedra structure.

自由基VS抗氧化物

自由基會產生在神經系統、免疫系統、血液循環系統等等,進而影響到人體各器官的運作,甚至於近年來許多醫生學者提出自由基病理:自由基是百病之源。本次實驗筆者挑選葡萄子、維生素C、綠茶來抑制清氧自由基(OH.)所採用的方法是將10%雙氧水製入注射筒並加亞鐵離子催化,,使其與抗氧化物反應,由於雙氧水分解會產生氫氣自由基與氧氣,因此筆者用倍率放大器(OPA)放大生成氧氣造成的電壓,並用Data Studio測量記錄,最後可由氧氣體積對電壓的趨勢圖看出抑制氫氣自由基的效果;Free radicals will be produced in our nerves system blood circulation immunization system etc. and they able to influene the operaion for our organs many medical scholars have even come up with "free radical pathology"-free radicals are sourse of all he diseases in recent years.In this study, I chose rape stone vitaminC and green tea to restrain hydroxide radicals(OH.) Here is summary of the experimental process. First,I put 10%hydrogen peroxide into an injector and then added ferrous ion to hydrogen peroxide to catalyze it. Second I let it reaact with the sample. Because hydrogen peroxide can produce hydroxide radicals and oxygen, I used the mutiplier(OPA) to amplify the pressure caused with the prducion of oxygen, measuring and recording resuls by the software"Data Studio"Finally, we can tell which antioxidant is more effective in restraining hydrode radicals from volume-voltage gragh.

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。

動物血型及血清的研究

人類血清中存在天然的抗體,能認識A型紅血球的A抗原及B型紅血球的B抗原,因此寫型不合的血液混合會導致血液凝結。在我們的實驗中,我們發現一種異體的血清與血球相混合也會產生凝集反應,顯示動物的血清中也存在認識異種異體紅血球抗原的天然抗體。然而在實驗是常用的基因相異的七種不同品系小鼠及一種大鼠血清中,卻看不到存有天然抗體可認識彼此血球的抗體而產生凝集反應,顯示老鼠似乎異於人類,血清中沒有天然抗體來引發彼此的血球凝集。而且抗馬血清可與經電泳分離後的馬血清在洋菜膠上形成三個沉澱線,但不會與老鼠血清及牛血清有任何反應。雖然抗馬血清與人及兔血清有交叉反應,但仍顯示出其結合的特異性。除此之外,我們發現來自不同品系的小鼠及大鼠的白血球彼此會互相反應並聚集在一起,顯示不同品系的小鼠及大鼠白血球可認識同種異體及異種異體的白血球抗原。因此不只是血清中的抗體,白血球本身也可認識同種異體及異種異體的抗原。所以除了人類血清中天然抗體及經由免疫注射產生的抗馬血清之外,為經過免疫注射的人或老鼠身上的白血球也具有認識同種異體及異種異體抗原的能力,因此我們認為不僅是抗體,連白血球都可當作鑑別物種的診斷工具。

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.

無尾翼飛行器之穩定與控制

無尾翼飛行器(Tailless Aircraft)在軍事上的價值極大,且對於目前正在起步的微飛行載具(Micro Air Vehicle)而言,亦是值得嘗試與投資的。然而,由於無尾翼飛行器缺乏用以平衡的水平尾翼,造成其靜態的不穩定,即使設法提高靜態穩定特性,但其氣動力阻尼低、穩定性仍舊不佳。操縱上更是困難,在飛行穩定性與控制系統設計上極其挑戰性。本研究目的在探討無尾翼飛行器之穩定性與控制技術,改善其先天之不穩定特性,考慮之項目有縱向靜態穩定性、動態穩定性、控制面與組件配置等因素等進行詳細之探討。首先,找出了適用於無尾翼飛行器之Reflex翼形,接著建立無尾翼飛行器之非線性縱向動態模式,然後針對一翼展8Ocm之小型飛行器進行外型設計,並觀察分析其實際飛行狀態,再以理論與經驗公式估算無尾翼飛行器之氣動力導數,探討其飛行穩定與操控性能。此外,並運用古典控制PID控制法則,設計控制器進行非線性受控系統之動態響應模擬。由模擬結果可看出,經由翼剖面改變與控制系統的輔助下,大幅提高了其性能,使得無尾翼飛行器克服了先天的不穩定特性,更提高了其發展空間 The tailless aircraft has a great value on the military use. Meanwhile, it is worthwhile to try and to invest in it for the investigation of MAV(Micro Air Vehicle), which is being developed now. However, because of lacking horizontal tail which is used for balance, the tailless aircraft is static unstable. Even with the attempt to enhance its characteristics of static stability, the stability of the tailless aircraft is still poor for the sake of it's low damping in aerodynamics. Therefore, it is a challenge to flight stability and control system designing. The purposes of this research are to study the stability and the control technique of the tailless aircraft. To improve its congenital lacking of stability, thought over the longitudinal static stability, dynamic stability and control system. First, find the "Reflex" airfoil is suitable for the tailless aircraft. Second, set up a non-linear and longitudinal dynamic model of the tailless aircraft. Third, design an 80cm span small airplane. Hence, observe and analyze its flying condition. Finally, utilize the theoretical and experiential equations to estimate the aerodynamic derivatives and investigate its stability and controllability. Besides, use the PID controller to proceeded the time-response simulation of the non-linear system. The result of simulation shows that the performance is improved through the change of the airfoil and with the auxiliary of the control system. With this improvement, the tailless aircraft overcome the congenital lacking of stability to broaden its utilization potential.