全國中小學科展

三等獎

Utilization of Starch for production of plastic-like material

The research is based on the production of biodegradable plastic-like material by only using household materials. Also, it can be made at home and it causes no harm to the environment. The biodegradable plastic-like materials made by different ratio of amylose, amylopectin, glycerol and water has different use. The finished product has smooth surface, highly transparency and well flexibility. Also, it can support strong load and be able to be deformed under stress. Ratios of components are tested on: 1. Easy to injection mold 2. Flexibility 3. Tensile strength and ductility & 4. Water resistance. It is found that the ratio of tapioca starch: glycerol: water = 1.5: 0.5: 9 can withstand 13N of force and 1.5: 0.93: 9 with high ductility. To improve water resistance, more amylopectin should be added to amylose. The best water resistance ratio is glutinous rice flour: tapioca starch: glycerol: water = 0.6:0.91:0.5:9 can withstand 16N force, while 0.6:0.91: 0.93:9 and 1.35:0.16: 0.5:9 with high ductility. All materials are available in supermarkets. Higher ratio of tapioca starch can produce bookmark, with laminate effect. More tough, higher ratio of glutinous rice flour can make cups, spoons and dishes.

Novel Biotechnological Approach for Recognition and Purification of Antibody: Lectin Affinity Membranes

Immunoglobulin G is a glycoprotein structured molecule that is produced by the immune system and protects organism from harmful effects of antigens. Ig G amount in the blood plasma is an appropriate indicator of; infection, cancer, diabetes, cardiovascular diseases, Alzheimer and other autoimmune diseases. Besides, purification of Ig G used in the treatment of these diseases from naturel sources is carried out at high costs on the World market. It is hard to obtain Ig G in high amounts and without any decomposes, that’s why it is important to develop new systems that will help to recognize and purify Ig G antibody. In this project, my purpose was; recognizing Ig G antibody with efficient, high amounted, fast, easily, with less toxicity, economically and purifying Ig G in high ratios from its natural sources. For this purpose p(HEMA-EDMA) membranes are synthesized with free radical photo polymerization method and characterized according to SEM images, swelling behaviors FTIR analysis and elemental analysis. In order to adsorb Ig G to polymeric membranes; polymeric membranes are activated with silanization agent (IMEO) and derivatized with Con A which is a lectin affinity ligand. In the SEM results it is examined that membranes are in spherical structures. Highest swelling value is determined as 224.8%.Binding of IMEO was demonstrated with FTIR and Elemental Analysis. Optimum conditions for Ig G adsorption to membranes are; 1.5 mg/ml initial Ig G concentration, 30 minutes of adsorption time, pH 4 citrate buffer 37 0C and without any different ion strength. Optimum adsorption capacity is determined as 253.8 mg/cm2 and it is also determined that this value is 7 times higher than nonspecific Ig G adsorption to p(HEMA-EDMA) membranes. Ig G adsorption-desorption cycles (5 times) proved that product is reusable without losing its adsorption capacity. According to the electrophoresis, Ig G could be desorbed in pure form without any denaturation to its structure.

Relationship between sexual deprived Drosophila, NPF, and the following behaviors

研究指出,公果蠅在求偶的過程中若被母果蠅拒絕,腦中的神經傳導蛋白NPF(neuropeptide F)會隨之下降,並提升其對酒精食物的攝取量。 我們的研究結果顯示求偶被拒的公果蠅是在「攝食酒精」後才對酒精成癮,而非在求偶被拒之後馬上去攝食酒精。而且,「求偶被拒」的公果蠅除了飲酒行為,也會提升其再求偶慾望。另外,我們利用Gal4-UAS系統調控了公果蠅腦中NPF神經的活性,發現公果蠅的NPF神經活性被抑制時,會出現與求偶被拒的公果蠅類似的行為。 最後,我們使用了NPF的螢光蛋白的抗體來標定NPF神經活性被激發以及抑制時腦中NPF的含量變化。透過這個結果,我們可以確定腦中NPF量的變化可以控制公果蠅對酒精的趨性、求偶慾望以及對酒精的攝食量。

ELISA-SERS分析法應用於檢測卵巢癌前驅因子-結合球蛋白

本科展在於改良鋰電池正極材料LiNi0.8Co0.2O2的物理性質及電化學性質。一般商業化的粉體材料,通常經由傳統的固態混合法,將Ni0.8Co0.2(OH)2與Li2CO3混合燒結而產生的材料粉體,此粉體呈現不規則的粒子形態及表面結晶顆粒不均。一般來説,不規則粒子內部有嚴重的結塊與橋構,這現象導致粉體有很多空隙及流動性不佳。此外,球狀粉體比不規則狀粉體容易覆膜均勻。因此球狀結構將變成一個改善材料粉體LiNi0.8Co0.2O2的期望方法,本科展利用共沉澱法製備球狀先驅物Ni0.8Co0.2(OH)2,然後再比較傳統的固態混合法,與本科展設計的溶液分散法及共沉析出法,三種不同方法所製備出來的粉體材料的優劣性,經過實驗證實,共沉析出法所製備出來的材料粉體,有最好的電容量與大電流放電能力及循環壽命,是個良好的改善材料的方法;反觀溶液分散法,不但材料沒有改善,反而造成更多的缺陷。

揮發性化合物抑制水稻去白化的分子機制

植物受逆境時常釋出VOCs (Volatile organic compounds)。本研究首度發現一種VOC-月桂烯(myrcene)可抑制水稻芽鞘之去白化現象(de-etiolation)。我們分別在螢光顯微鏡與穿透式電子顯微鏡(TEM)觀察水稻芽鞘,發現葉綠素分布與葉綠體分化均被月桂烯所抑制。研究發現水稻在月桂烯處理下去白化現象受抑制,是因葉綠素合成相關基因ACSF被抑制所致。同時有一些參與光合作用光反應、 碳反應基因表現也有受影響。月桂烯影響光合作用相關基因,有三種不同類型:一、黑暗下基因產物幾乎不表現,照光後才累積,累積量受月桂烯抑制,如RCA、 ISP、G3PD;二、在暗處下基因產物之累積就被月桂烯大量抑制,如ACSF,ATPS;三、黑暗下基因產物之累積受月桂烯抑制,同時月桂烯抑制照光後光誘發基因累積速率,如FNR。由基因產物累積量推測轉錄因子MYB-TF1參與月桂烯抑制去白化現象,且推測RCA、ISP、G3PD為其下游基因。我們進一步分析轉譯後修飾,在磷酸蛋白分析中,我們發現月桂烯會抑制35 kD 的phosphoprotein (pp35) 之去磷酸化,這暗示pp35可能參與月桂烯抑制水稻去白化現象。VOCs含天然毒素,可抑制附近植物生長,可為天然農藥。

雙橢圓交點軌跡之研究

(PA)+(PC) =t為以A、C為焦點的橢圓,滿足(PA) +(PC)=(PB)+(PD) =t的P點軌跡可視為以A、C及B、D為焦點且長軸等長的橢圓在長軸變化過程中的交點軌跡,稱該曲線為EIC(AC,BD)。本研究主要討論四邊形ABCD為鳶形時,EIC(AC,BD)的代數方程式、曲線變化情形及其是否平滑。我們可將EIC曲線分為三類: 1.兩條非封閉曲線 2.一條非封閉曲線及一條封閉曲線 3.一條封閉曲線。由兩條曲線變為一條曲線的臨界條件為(BA) ̅=(BC) +(BD),此時圖形為一條非封閉曲線及一點(B點),此時EIC(AC,BD)曲線族的包絡線為以B、D為焦點、長軸長為(AC) ̅的橢圓。另外,從代數方程式得知除了原點為奇異點,EIC曲線為平滑曲線。從圖形可發現EIC曲線與雙曲線、橢圓曲線(Elliptic Curve)、蚌線(Conchoid of de Sluze)極為相似,而其實質關聯性則有待未來研究。

在地表上畫畫-球面上的尺規作圖

在這分作品中我們在球面上尺規作圖。目的是要完整描述球面上可作的角度。我們從平面尺規作圖的知識出發,卻遇到了困難,像是有很多平面尺規作圖的方式不能被如法炮製地運用到球面上。為了達成目標,我們著手探討在球面上和平面上作圖方式的關係,方法如下:先定義兩個重要名詞S :球面上能作角度(弧長)的集合和P:平面上能作角度(弧長)的集合。透過向量方程式的證明我們得到S⊆P。利用我們從球面三角學公式衍生出的作圖方法,並藉由「體」證明出P⊆S。在P=S 的基礎上,我們引用伽羅瓦理論的已知結果,終於得到結論,也就是「球面上一個角度可作若且唯若其餘弦值為1經過有限次的加減乘除與開平方根運算」。最後我們也給出了球面上正4邊形、正5邊形和正17邊形的作法。

Understanding the Modern Diagnoses of Protein C Deficiency "Pcd" with Unknown Gene Plays a Critical Role in the Inherited Thrombophilia

Protein C deficiency (PCD) is found in 1 out of 200 to 500 persons in the general global population which is also one of the common conditions of Inherited thrombophilia, it’s characterized by an increased tendency of blood to clot in human blood vessels. It is caused by several factors including mutations in the genes involved in thrombin binding, protein c activation and numerous clotting factors. This includes F5 (Factor 5 Leiden) gene on chromosome 1q24.2, F7 (Prothrombin) gene on chromosome 13q34, SERPINC1 (serpin peptidase inhibitor C) on chromosome 1q25.2, SERPIND1 (serpin peptidase inhibitor D) on chromosome 22q11.21, HRG (Histidine Rich Glycoprotein) on chromosome 3q27.3, PLAT (Plasminogen Activator) on chromosome 8q11.21 and THBD (Thrombomodulin) gene on chromosome 20p11.21. In the current study, a three Saudi families with inherited thrombophilia has been recruited to identify the underlying cause of this special condition. Whole exome sequencing, targeting all coding exons of the human genome, was performed using Illumina Nextera library preparation kits followed by paired-end sequencing on Illumina NextSeq500 instrument. Reads quality control was performed and reads were aligned to the reference genome using BWA software. Variants calling and annotation was performed using GATK. All known genes involved in causing inherited thrombophilia All known genes involved in causing PCD were excluded by whole exome sequencing. The genes that were previously reported to be involved in inherited thrombophilia were checked for any causative variant. No mutation has been identified in known genes. identifying a novel gene underlying PCD. The Result of this study will hopefully pave the way to better understanding the disease pathophysiology and help in developing DNA based diagnosis, carrier screening and somatic gene therapy.

葉酸缺乏及葉酸補充調控乳癌細胞轉化成癌幹細胞並促進體外腫瘤形成

研究指出葉酸營養狀態與乳癌的風險有相互關聯且癌幹細胞是扮演癌症轉移的主要角色。葉酸缺乏和葉酸補充皆能促進癌細胞的轉移。本研究探討葉酸營養不良和葉酸補充是否會促進乳腺癌細胞轉變成癌幹細胞,將乳癌細胞株養於正常葉酸、低葉酸和高葉酸中,藉以模仿癌症病人的葉酸營養狀態。細胞在每個葉酸濃度中培養2、 4 、 8 天後再培養於腫瘤球體培養液中並測量四種幹細胞標記-mTOR,SHH,Sox2和Nanog。結果顯示:低葉酸會導致癌細胞的生長停滯,藉由標記的表達增加顯示長期低葉酸會促進細胞轉變成癌幹細胞。於腫瘤球體培養液時,低葉酸組亦較對照組於體外產生較大及較多的腫瘤球。高葉酸組會加速癌細胞的增殖和向癌幹細胞的轉變且細胞增生較快並表達較多的標記,其腫瘤球體亦是最大和豐富的。總之,低葉酸和高葉酸都增強了乳腺癌細胞的腫瘤生成和轉變成癌幹細胞。

The Locus of Mid-Tangent Points of Planar Curves

In this project, we defined a mid-tangent point with respect to a fixed point X and a tangent at a point Y on a planar curve C as a point on the tangent that is equidistant from X and Y. We studied the locus of mid-tangent points of conic sections. We found that the locus of mid-tangent points of most conic sections are non-linear curves. However, we observed and proved by using Euclidean geometry that the locus of mid-tangent points of circles are straight lines. The mapping defined by mid-tangent points was studied further. The similarity between a mid-tangent mapping and a stereographic projection was displayed as a one – to – one correspondence function. We also extended the concept of mid-tangent points to three dimensional space and found that the similarity with the stereographic projection was retained in higher dimensions. Finally, we studied the locus of mid-tangent points of a sphere to create a mapping of the sphere to a plane.