全國中小學科展

2023年

探討番茄根圈菌對農桿菌的生物防治

前人以含農桿菌 C58(Agrobacterium tumefaciens C58)土壤接種番茄小苗後,發現有些番茄未產生腫瘤,故推測其土壤根圈中,有能抑制農桿菌 C58的細菌。本研究從番茄小苗根圈分離並純化培養細菌,再透過抑制圈實驗測試分離菌。結果發現分離株YA7-1,有顯著抑制農桿菌 C58的效果,進而測試其他農桿菌菌株。結果顯示YA7-1對多種農桿菌具拮抗能力,且不同於現行的生物防治菌農桿菌(Agrobacterium radiobacter K84 and K1026)有高選擇性限制。定序其16S核糖體核糖核酸基因片段,序列比對為節桿菌屬(Arthrobacter)。經由接種試驗得知YA7-1對番茄沒有致病力,且預先接種於根部時,可降低土壤中農桿菌誘導腫瘤的機率。測試YA7-1對其他植物病菌及非病原微生物的抑制效果,發現YA7-1具有廣效性的抑菌能力。藉由分析培養液上清夜的實驗可得知YA7-1的抑菌因子為分泌物質。完成YA7-1全基因體定序後,找到四種可能被YA7-1分泌且具有抑制性的次級代謝物。未來將繼續找尋YA7-1的抑菌物質與機制,來完善對根癌農桿菌或其他植物病原菌的生物防治。

Overcoming Motion Disorders

Helping in overcoming the motion disorders is an important thing which deserve striving for. Every year number of people who have MS or paresis (paraparesis) is increasing. The device has effective results for the patients and it backs to finding the conditions of natural treatments in the device. Obviously, this device helps them to keep standing and achieve the required exercises the movement like normal people by using their hands. The degree of improvement differs from person to another as depends on the hardness of the disease and injury kind.

surgical masks and microplastics in our airways

The surgical mask has been our daily companion since the outbreak of the Corona pandemic. The nonwovens (outer layers, not the filter membrane) from which the surgical mask is constructed consist of very long and thin polypropylene fibers. This leads to the question of whether microplastics are released during breathing through the surgical mask, which could enter the respiratory tract or the lungs. This would have a negative impact on our health, depending on the size of the detached fiber fragments - the smaller the worse because they can enter much deeper in our respiratory tract. In order to investigate the question of whether fiber fragments are released during breathing through a surgical mask, a filtration device was built. The filters were examined under an optical microscope after filtration. If fiber fragments would detach from the surgical mask, they would be found on the filter. Different surgical masks were tested, those that were not worn at all to surgical masks that were worn all day. It was found that fiber fragments were coming off the surgical masks. There were different fiber fragment types. Some fiber fragments were still undamaged (exhibited nice fractures), while others were frayed. Clump-like fragments occurred, but also smaller fine fiber fragments. All these different fiber fragments had a certain size, so that they could be called microplastics. The remarkable result of the whole study is that there is a direct correlation between the wearing time of the surgical mask and the number of detaching fiber fragments. In the case of the unworn surgical masks, 10 times fewer fiber fragments occurred during filtration than in the case of the surgical masks that were worn all day.

引菁拒鹽 – 探討田菁較綠豆耐鹽的機制

隨著越來越劇烈的天災,對農作物損害造成了許多危機。去了解植物如何對抗逆境,是刻不容緩的。田菁是台灣重要的綠肥作物,我們也常在濱海鄉村的農田看到其存在;綠豆是常用作物,在研究上與日常生活中都很常見,同樣身為豆科植物,兩者對於常見的鹽逆境的反應是否有差異呢?本研究透過比較田菁與綠豆兩種常見豆科植物,深入了解並比較其耐鹽機制。首先,在外表型上,田菁幼苗在鹽逆境下的發芽率、芽長、根長和鮮重皆有較好的生長情形。其次,鹽逆境下田菁的氣孔密度較低,進而可以減少水分蒸散。第三,在生化測試中,田菁在POD和CAT兩個酵素上,表現出更高的酵素活性。這些抗氧化酵素可以幫助植物在逆境下更容易生存。總之,田菁由於更高的抗氧化能力而具有更好的耐鹽性,並且將更多的能量用於生長更複雜的根結構。此外,我們發現田菁在根中出現中柱分離和更多的脯氨酸累積,以幫助它保持水分和遠離鹽害。上述所有機制使田菁在鹽逆境下具有更好的適應與生長。我們希望這項研究可以在未來應用於農業上,減少不可預測的環境災害造成的經濟損失。

Utilization of Escherichia coli in Contiminated Water in the Citarum River as a Dual Chamber Baed On Microbial Fuel Cell (MFC) Substrat

Citarum River is the longest and largest river in West Java. The upstream of the Citarum River starts from Mount Wayang, Bandung Regency and ends at the mouth of the Java Sea which is located in Muara Gembong, Bekasi Regency. The Citarum River plays an important role as raw water for PDAM drinking water, supplies electricity in Java-Bali and provides water for rice field irrigation in West Java. Citarum watershed is dominated by the manufacturing industry sector such as chemicals, textiles, leather, paper, pharmaceuticals, metals, food and beverage products, and others. Based on data from the World Bank, every day, the Citarum River is polluted by approximately 20,000 tons of waste and 340,000 tons of waste water with the majority of the waste contributors coming from 2,000 textile industries. By looking at these events, there is no doubt that the sustainability of the ecosystem and the environment in the Citarum River is damaged and polluted. (Zahra Fani Robyanti; 2020). The West Java Regional Environmental Management Agency stated that the content of E. coli bacteria in the Citarum River had increased. The bacteria that cause diarrhea come from industrial and household waste. In addition to E. coli bacteria, other pollutants in the Citarum River that have increased are biological oxygen demand (BOD), chemical oxygen demand (COD) and Suspended Solids. One of the efforts that can be done regarding E. coli bacteria that pollute the Citarum river is to make it as a substrate for Microbial Fuel Cell (MFC). Bacteria present in organic media convert organic matter into electrical energy. The nature of bacteria that can degrade organic media (enrichment media) in MFC produces electron and proton ions. It is these ions that produce an electric potential difference so that energy can be generated. Generally in conventional systems, MFC consists of two chambers consisting of anode and cathode chambers. The two spaces are separated by a membrane where proton exchange occurs. This system has not fully worked with bacteria because only the anode side contains bacteria, while on the cathode side it still works using chemical compounds such as Polyaluminum Chloride (PAC). However, recently MFC has been developed using bacteria at the cathode, or better known as biocathode. Bacteria in the cathode space have the same function as electron mediators that were previously carried out by chemical compounds. In many studies on MFCs, acetate is commonly used as a substrate for bacteria to generate electricity. These chemical compounds are easier for bacteria to process than wastewater. Acetate is a simple chemical compound that serves as a carbon source for bacteria. Another advantage of acetate is that this compound does not cause other reactions to bacteria such as fermentation and methanogenesis at room temperature. Based on this thought, the author will design a study entitled Utilization of Escherichia coli Bacteria in Contaminated Water in the Citarum River as a Dual Chamber Based Microbial Fuel Cell (MFC) Substrate.

Silver Moringa Cloth: Silver Nanoparticle Fabric Based on Moringa Extract (Moringa oleifera) as Antibacterial Against Methicilin Resistant Staphylococcus aureus

Staphylococcus aureus is addressed as one of the most common pathogens in hospital settings and in the community. This pathogen causes invasive infections, sepsis, and death. The emergence of antibiotic-resistant bacteria is due to bacterial mutations and the use of antibiotic drugs that are not by procedures. Resistance makes MRSA infections difficult to treat, resulting in high healthcare costs. These problems lead to an urgent need to find alternative drugs to control MRSA infection. Therefore, developing new drugs and procedures such as antibacterial nanoparticles, are particularly promising. Indonesia has many medicinal plants with antibiotic activity, including Moringa oleifera. Moringa oleifera contains several active compounds such as alkaloids, flavonoids, and saponins which are known to have antibiotic activity. Silver nanoparticles or AgNPs are currently used as antimicrobial agents because they are toxic to prokaryotic cells (bacteria) but relatively safe for eukaryotic cells. AgNP synthesis mediated by M. oleifera extract has the advantages of being non-toxic, pollution-free, and environmentally friendly. Sisal is a potential source of naturally derived fabric and a prospective source of multifunctional textiles. Recent studies have utilized and functionalized sisal to develop composite materials. However, functionalizing of sisal using nanosilver-based materials has not been studied yet. Bioactive chemicals from plant-extracted nanoparticles also provide additional antimicrobial properties. This study aims to produce AgNPs mediated by M. oleifera leaf extract and to analyze its antimicrobial effect on MRSA growth. The powdered Moringa (4g) was boiled with 100 ml of distilled water (550 C) for 15 minutes. The mixture was filtered through Whatman No 1 filter paper and store refrigerated. The nanoparticle was synthesized by rinsing sisal fabric cloth to several concentrations of AgNO3 (1mM, 10mM, and 20mM) with Moringa extract. Nanoparticle synthesis from AgNO3 done with the help of Moringa oleifera extract. The resulting AgNPs have MIC values (Minimum Inhibitory Concentration) and MBC (Minimum Bacteriocidal Concentration) of 1.25 mg/ml. The resulting silver nanoparticles showed antibiotic activity against MRSA with an average inhibition zone diameter of 15.677 mm. XRD and SEM studies are going to be held to support the data.

冰棒棍骨牌模型建立與運動分析

本研究主要研究冰棒棍骨牌在崩解時波峰的軌跡,並且逐步分析物理原理。首先,討論冰棒棍的基本性質,接著拍攝崩解時的影片,並分析產生眼鏡蛇波的原理,過程中發現了不同的排列順序會分別產生眼鏡蛇波或C波,以及當以眼鏡蛇波結尾時,波峰都會有一個旋轉的現象我們使用了Tracker程式來追蹤冰棒棍骨牌崩解時的波峰軌跡,且發現大部分冰棒棍軌跡都呈現相同的函數關係,並建立模型來研究其性質。 本研究已有初步的結果,我們計算出了冰棒棍的楊氏係數,並且做出了冰棒棍波形的擬合。另外也從不同觀察角度觀察出冰棒棍的運動情形,分析出單一冰棒棍的整體受力與運動情形。根據單一冰棒棍的轉動狀況,觀察出類似於進動現象,並對此深入討論。 未來我們希望能夠結合楊氏係數、冰棒棍波形疊合以及冰棒棍受力情形來建立專屬於冰棒棍波的物理模型,並研究其轉動互換模式。將其利用在工程學上。

以粒線體轉移治療動脈血管內皮細胞功能失調及動脈粥狀硬化疾病

動脈粥狀硬化疾病的風險因子及血管擾流會造成血管內皮細胞內的粒線體失去功能,導致內皮細胞功能失調,進而引起動脈粥狀硬化疾病的後續病程,如斑塊形成。本研究主要探討粒線體轉移療法,是否能改善受到擾流影響的血管內皮細胞功能失調。首先,我們分別觀察並比較擾流與順流下的人類動脈血管內皮細胞,兩者細胞形態與內皮相關功能基因表現量的差異。其次,我們從順流處理的細胞中分離取得健康的粒線體,轉移入擾流處理的細胞中。接著以生物能量代謝分析儀,檢測轉移粒線體後內皮細胞呼吸鏈與代謝的功能是否隨粒線體的轉移而有所改善。實驗結果確認,粒線體轉移處理可改善擾流組細胞的呼吸鏈功能,細胞的有氧呼吸與產能代謝皆有改善。本先驅性研究希望有助於開創以粒線體轉移技術作為心血管疾病治療的創新療法。

DECREASING CANSAT ANGULAR VELOCITY USING DEPLOYABLE FINS

CanSat (a can-size satellite) flight data revealed the occurrence of high spin angular velocities along the vertical axis of a CanSat during a parachute descent phase. A novel aerodynamic stabilization system of deployable fins was designed to decrease angular velocity. Deployable fins were attached to servomotors (rotary actuators) to provide control authority during the CanSat descent phase. Deployable fins positions were calculated based on an onboard gyroscope data using a PID (proportional-integral-derivative controller) regulator and a moving-average filter. After the assembly and the initial testing, the system was flight-proven by dropping it from a drone with and without enabling the stabilization system

Analysis on a New Electric Field Measurement Method Using Ionic Propulsion Propeller

Given the high sensitivity of electronic instruments, electromagnetic field intensity measuring is now becoming an essential part of the industry. Current electric field intensity meters are unfit for individual use and focus mainly on electromagnetic radiation rather than the field itself. In ionic propulsion, the propulsion force is proportional to electric field intensity but the use of this property on measurement remains largely unexplored. Here, our team investigates ionic propulsion in electric fields generated by electro-static methods and then systematically varies the point of measurement inside the field, thereby altering the intensity of the field without focusing on electromagnetic radiation. By combining the Van de graaff generator with an adjustable ionic thrust propeller, we find that the propeller speed which is proportional to the electric field is directly determined by the electric field intensity. Furthermore, we applied stroboscopy to the system to measure RPM, and have achieved the direct interaction between field intensity and RPM, which could be a new meter for field intensity measurement.