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熱門關鍵字: the king 水果 豆漿 電腦
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HOST TARGET PROTEINS OF SPIKE PROTEIN OF SARS-COV-2

Coronavirus Disease 2019 (COVID-19) is a newly emerged infectious disease caused by the new severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV-2). In less than one year, the virus has spread around the entire world, killing millions of people and disrupting travel and business worldwide. During infection, the virus uses its Spike protein to dock onto the Ace2 protein on the surface of its human host cell. Spike is 1273 amino acids long and only a short fragment of Spike (319-541) is sufficient to bind Ace2. We hypothesized that the remaining protein sequences of Spike might have functions for viral replication beyond the binding of Ace2. We have performed Split-Ubiquitin protein-protein interaction screens to isolate human proteins by their ability to bind to Spike, and we have identified Annexin2A2 and Cytochrome b as novel human protein interaction partners of Spike. Annexin2A2 is involved in both endocytosis and exocytosis, and the protein interaction with Spike might help the virus to enter and exit its host cell. The presence of the mitochondrial Cytochrome b protein inside the cytosol promotes apoptosis, and the protein interaction with Spike could speed up sapoptosis of the infected human cell. The Nub cDNA libraries that we have generated also allowed us to screen for synthetic peptides that interact with Spike. We have isolated two synthetic peptides, FL1a and FL7a, derived from the non-coding parts of human mRNAs by their ability to interact with Spike. We found that both FL1a and FL7a interact with the C-terminal half of the Spike protein. We also found that FL7a is able to block the Spike-Spike self-interaction at the C-terminal half of the Spike protein and we think that this could block the reassembly of the Spike protein in the host cell during viral reassembly. We hope that those synthetic peptides could be used as drugs due to their ability to block protein-protein interactions of Spike with human host proteins that are essential for viral replication.

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Development of an Audio Modulated Tesla Coil

Originally, the Tesla transformer was developed to transmit energy and messages wirelessly. But it did not prove itself for either of these applications, so today it is only used for research purposes. Over time, the Tesla transformer has evolved and improved. Today it is possible with Tesla transformers to generate powerful and highly precise controlled discharges. During operation, impressive high-voltage discharges occur at the transformer. A tesla transformer is basically a high voltage generator that achieves a voltage boost by using two magnetically coupled LC series resonant circuits of the same resonant frequency. The Dual Resonant Solid State Tesla Coil (DRSSTC) built in this work has a high power IGBT half bridge module to excite the primary resonant circuit at the resonant frequency. The IGBTs are driven in such a way that audible pressure waves, and therefore music, are generated by the electrical discharges at the high voltage electrode. Within the scope of this work were the following two questions: - How is a DRSSTC designed and built? The DRSSTC system realized in this work is about 80 cm high and reaches about one-meter-long discharges. The design, development, and construction of the transformer are documented in detail and extensively in this thesis. - How does one measure an electrical voltage of 200,000 V, which changes sign more than 100,000 times per second? Two approaches have been taken to measure the voltages. Derived from the energy balance of an ideal capacitor and an ideal coil, a secondary voltage of about 200 kV was calculated via secondary current measurement. The second approach uses a voltage measurement via an in-house developed measuring electrode and a calculated divider ratio between the measured voltage and the secondary voltage. A relatively unrealistic secondary voltage of about 750 kV was measured since the divider ratio depends on approximate values. Nevertheless, the measuring electrode can be used for investigations of the voltage curve, or the divider ratio can be calibrated via the secondary current measurement. The development of such a transformer laid the foundation for much further research and scientific analysis.

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Anti-bacterial Crab bio-bandages with Bio-dressings 2.0

Commercially available bandages such as hydrocolloid are neither biodegradable nor anti-bacterial. Chitin is known to be the second most naturally available polysaccharide which could be transformed to chitosan which is known to be anti-bacterial (Hasan, 2018) (Chao, 2019) and haemostatic (Okamoto, 2003) (Hu, 2018). Chitosan can be further converted to hydrogel which is bio-degradable and has good water absorbance. Anti-bacterial crab bio-bandages and crab bio-dressings should be bio-degradable as it took 42 days and a month for complete bio-degradation respectively, so they should be better than commercial bandages such as Nexcare Hydrocolloid as the disposal of anti-bacterial crab bio-bandages with bio-dressings would no longer pose burden to landfilling or threat to our environment. Anti-bacterial crab bio-bandages with bio-dressings are anti-bacterial with degree of deacetylation of DD% (measured using FTIR Spectrum II) 82.6% (due to the presence of chitosan) even without the application of other anti-bacterial agents and hence can provide complete protection of wounds from skin and soft tissues infections and haemostatic (due to the presence of chitosan). After testing and certification based on IS997:2004 and BS EN 13726-1, they should meet many requirements specified. Anti-bacterial crab bio-bandages should be eligible for marketing. Some results were as follows: 1.4 Anti-bacterial effect of crab hydrogels and roasted crab hydrogels Pure chitosan, crab chitosan, crab hydrogels and roasted crab hydrogels showed significant anti-bacterial effect. NO oral bacterial colonies were present in drinking water with crab hydrogels. Thus crab hydrogels could serve as effective anti-bacterial wound dressings. 1.6 Basing on IS997:2004 standard, the load per unit of area of anti-bacterial bio-bandages was 342g/m2 which met the minimum requirement of 36g/m2, the anti-bacterial bio-bandages had stronger tension strength (>20N both in dry and wet conditions) than commercial hydrocolloid. (2.7N dry 2.8N wet) which was comparable with that required (50-67N) and pH of about 7 which met the pH range of 4.5-8. 1.7 The FSA Free-Swell Absorbency of synthetic blood of crab hydrogel bio-dressings was 1.86g per 5cm x 5cm dressing which was much higher than that of commercial hydrocolloid (0.299g per 5cm x 5cm dressing) based on BS EN 13726-1.

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微結構下的魔術師 ──萊頓佛斯特的溫度效應The study of Leidenfrost effect on micro structure surface by using frequent water droplet.

leidenfrost effect”是水滴能在熱表面產生蒸氣層並隨機跳動。我們便設想利用此特殊蒸氣層達到讓水滴往固定方向前進,甚至優化其加速結構。 我們設計 (角度θ=30°、45°、60°)×(高度h=1.0 mm、1.5 mm、2.0 mm)共9種具數學意義的微結構。測量微結構在(160°C -350°C)溫度下水滴的速度、生命週期,並獨創「珠光粉慢動作攝影」研究形變、熱流。 我們提出未有文獻紀錄的空腔體積、有效接觸面、水滴外部形變機制、內部熱流循環等機制。利用上述資訊建構運動模型,發現θ=60°、h=1.0 mm水滴有最快的速度。且發現高溫段(表面溫度≥300℃),任何微結構,生命週期差距都極小。我們獨創性提出水滴在微結構下“leidenfrost effect”數學模型,理論值與數據吻合,成功解釋水滴的運動機制。

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An Easy Method to Discuss Properties of Simplified Solid-state Tesla Coil

Wireless transmission products are widely used in our daily life. In this research, we focus on knowing how solid-state tesla coil works in different conditions and finding the best parameters through an easy way. In our work, a commercial electroscope was used as detector for measuring the strength of radio wave created by our simplified tesla coils. In fact, many factors would lead to experimental erorrs such as detectors, selected types of NPN BJT components, applied voltage and measuring position of height. Therefore, all of the factors were under control to make sure of accuracy and precision for our designed measuring method. In our experiment, graphics of radio wave distribution around tesla coils were drew by mathemetic software of GeoGebra. It shows the BJT types of 2n2222 had good performance for wireless transmisstion efficiency. To our surprised, we found the extended wires (called antenna) from the top of tesla coil also had an ability to transfer electromagnetic energy, and had good retention if the extended wires were within the length of main coil’s height. Finally, the shape’s and size’s effect was determined by our testing work. The result shows that pipe’s length, pipe’s diameter and turns ratio of two coils had great influence on tesla coil’s transmission efficiency. It was found that the tesla’s performance would be more efficient if wire was used to make the length twice rather than make the diameter twice. However, the turns ratio of secondary coil to primary coil would change while making the length twice. To avoid that, we fixed the length and decrease the turns of primary coil. At last, we found tesla coil must work at the turns of primary coil higher than two. Furthermore, the frequency of radio wave not only had less relationship with their length or diameter but also had less relationship with types of BJT In our study, our handmade tesla coil was succesfully applied for wireless charging and we find that the induced voltage decrease in propotion to cube root of distance between tesla coil and induced coil.

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Consensus-based Machine Learning Model in the Scoring for Hepatic Steatosis Severity

研究目的:脂肪肝的盛行率在全世界的現代化國家都在增加。病理醫師在評估脂肪肝的嚴重等級時,常缺乏參考意見以減少差異。許多地區也缺乏病理醫師。本研究旨在建立一個有效評估脂肪肝嚴重程度的病理組織學人工智慧模型。研究過程:本研究經由臺中榮民總醫院人體研究倫理審查委員會審核通過,篩選後取得病理資料庫中適合的肝臟組織切片,由兩位病理醫師獨立為肝組織中脂肪堆積的程度評分。再以病理醫師討論後的共識答案為分級標準,來訓練人工智慧模型。研究結果:在100個樣本的獨立測試中,人工智慧模型和病理專科醫師的評分,有71%完全相同、27%差異只有一個等級、2%差異2個等級、而沒有2個等級以上的差異。結論及應用:我們已初步建立一個可以評估脂肪肝嚴重程度的人工智慧模型。這模型可為將來人工智慧的臨床應用,建立一個良好的基礎。

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Limited Query Black-box Adversarial Attacks in the Real World

We study the creation of physical adversarial examples, which are robust to real-world transformations, using a limited number of queries to the target black-box neural networks. We observe that robust models tend to be especially susceptible to foreground manipulations, which motivates our novel Foreground attack. We demonstrate that gradient priors are a useful signal for black-box attacks and therefore introduce an improved version of the popular SimBA. We also propose an algorithm for transferable attacks that selects the most similar surrogates to the target model. Our black-box attacks outperform state-of-the-art approaches they are based on and support our belief that the concept of model similarity could be leveraged to build strong attacks in a limited-information setting.

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滾動體在旋轉圓盤上運動之軌跡探討(The motion of a rolling sphere on a rotating disk)

球體在旋轉平台上的運動分三階段:進動階段、螺線振盪階段、打滑階段。進動階段、螺線振盪階段為兩個運動模式的疊加:迴旋半徑漸增的螺旋線運動、向平台中心靠近的平移運動。當迴旋半徑漸增至滑動摩擦力的上限值,球進入打滑階段並向外甩出平台。 研究紀錄球體質心運動參數,並以接觸點準靜態理論計算及滑動-滾動摩擦模型進行數值分析,找出各種變因與運動參數間的關係。 結果發現滾動階段中鋼球作迴旋運動的頻率f球和平台旋轉頻率f盤和有正比關係,且比例值和球標準化轉動慣量δ正相關。由滾動階段過渡到滑動階段的最大迴旋半徑Rmax和f球2成反比、和δ呈負相關、和滑動摩擦係數μk成正比。滾動摩擦使球向平台中心靠近,也使迴旋半徑漸增。平台傾斜或呈錐狀時,球體的運動會向水平方向偏移。

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Properties of possible counterexamples to the Seymour's Second Neighborhood Conjecture

The project is devoted to the study of the Seymour’s Second Neighborhood conjecture by determining the properties of possible counterexamples to it. This problem has remained unsolved for more than 30 years, although there is some progress in its solution. The vector of the research is aimed at the analysis of possible counterexamples to the conjecture with the subsequent finding of some of their characteristic values. In addition, attention is focused on the generalized Seymour’s conjecture for vertex-weighted graphs. Combinatorial research methods and graph theory methods were used in the project. The author determines the values ​​of densities and diameters of possible counterexamples, considers separately directed graphs of diameter 3. The conditions under which specific graphs cannot be counterexamples to the Seymour’s conjecture with the minimum number or vertices are defined. The relationship between the Seymour’s conjecture and vertex-weighted Seymour’s conjecture is explained. It is proved that if there exists at least one counterexample, then there exist counterexamples with an arbitrary diameter not less than 3. Under the same condition, the existence of counterexamples with a density both close to 0 and close to 1 is also proved. The equivalence of the above two conjectures is substantiated in detail. It can be concluded that if the Seymour’s Second Neighborhood Conjecture is true for a directed graph of diameter 3, then it is true for any digraph, so that problem will be solved. Moreover, if the conjecture is true, then vertex-weighted version of this conjecture is true too. That is why a digraph of diameter 3 needs further research.

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MENTAL STRESS IN TEENS

Observation: Over stress is a one of the major hindrance in realizing true potential. I observe source and effect stress in teens in my nearby society. Observations are as follows: • Parental pressure for excellence in study • commercial purpose • Inferiority complex • Scolding and intimidating children in public Objective: To study mental Stress in adolescence and to find a solution to the cause of mental Stress. • Mental stress should be reduced in adolescence. • In adolescence, parents should convince the children that it is right and wrong because of the pressure put on the children. Experiment: We conducted a survey to find mental stress in children, which was done by a quiz. We conducted this survey between parents. Samples of some quiz :- For Parents: - • Do you scold your child. • Do you think your child is under stress. For Children’s:- • How much do you study in one day. • How do your parents treat you. We go through the experiment: - We surveyed how a child reacts when he is under mental stress. • His brain becomes weaker than a healthy child. • He slowly feels weak around himself. • Parents should keep an eye on children in adolescence. We found many such reasons during the survey. Conclusions: After completing this project we have concluded that the biggest root cause of stress in adolescence is that the mother is unable to give time to the children and there is pressure on them to study, due to this, between parents and children Distance is increasing due to which stress is also increasing.

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Generating Conditioned Air in an Open Space in Accordance with Sustainable Architecture Criteria (Based on Wind-Catchers)

Nowadays, cooling open spaces in hot seasons without using fossil fuels has gained a lot of attention. In this regard, natural air conditioning is a great method for conserving energy that can be used for reducing energy consumption and environmental pollution. Structures like windcatchers are used for natural air conditioning as a building component in warm climates since they are placed in the path of the wind and direct the wind to play a significant role in reducing the temperature. The main objective of the current study is to explore air conditioning in open spaces based on sustainable architecture. The current study reviews the relevant literature from credible journals, and it includes studies with relevant subjects published from 1851 to 2021. The findings show that implementing this design project can result in significant advances in terms of reducing humidity, removing dust and insects from the air, conserving energy, reducing the global temperature, using renewable energies, and producing conditioned air for the area

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Locus of the Points on Circumference of the n-th Circle that Formed by Moving the Center of any Radius Circles on the Outermost Circumference of Preceding set of Circles

This project aimed to study the motion which occurred from the end point on the circumference of the outermost circle by moving the center on the circumference of a preceding circle and the center of an innermost circle at origin. According to the study, when angular velocity was changed, it caused the different of loci. Based on the above information, finding the locus of the point on circumference of n-th circle that formed by moving the center of any radius circles on circumference of preceding set of circles was studied to get general equation. A set of circle and locus were created with GSP program. First, set the same radius circles on the X-axis with the first circle at origin, then found the relationship that occurred from the characteristics of locus. The result showed that if the ratios of angular velocity are 1:1:1, 2:2:2, 3:3:3, ..., …, n:n:n or 1:2:3, 2:4:6, 3:6:9, …,nw1:nw2:nw3, the characteristics of locus will be the same, while the others will be different. Finally, the equation of locus was found as follow: (x,y) = { ..........see in abstract...........} when .........see in abstract........... Where ri is the radius of i-th circle, zeta i is an angle between the radius of i-th circle and X-axis, wi is the angular velocity, t is elapsed time and alpha i is a starting angle between the radius of i-th circle and X-axis.

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