2022年

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.

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.

Harmful microorganisms in food can cause deterioration of human health, poisoning and in some cases even death. Especially fresh meat and chicken products create a suitable environment for the growth of microorganisms in terms of the nutrients it contains, water activity and pH level. For this reason, detection of microorganisms in meat products is an important issue in terms of food safety and human health. In this project, it is aimed to detect live microorganisms in meat products, especially chicken meat, in a simple, non-destructive, non-contact and fast way using laser speckle method. Laser speckle images of healthy and stale chicken meat were taken, contrast parameter and correlation analysis of the obtained patterns were made. It was observed that the contrast parameter for staled chicken meat increased by approximately 3 times compared to fresh chicken. This increase provides an understanding of the difference between contaminated chicken and fresh chicken. Speckle density changes over time in relation to the movements of living microorganisms. Thus, the correlation in laser speckle density patterns taken from contaminated tissues is disrupted. In the measurements taken with photodiode, by analyzing the change of light intensity of the speckle patterns on fresh and contaminated tissues over time, the detection of microorganisms was made easier and more precisely without the need for image processing. The proposed measurement system is a new method that detects meat contamination with laser speckle imaging. It can be developed and made portable and can be used easily in homes. Since it is a simple, non-destructive and fast method, it can be used to determine the shelf life of meat in food distribution places and markets. In addition, it has the potential to be calibrated and used for other food products other than meat products. The system developed with this study is cheap and easy to use, and the laser speckle imaging method is used in a different field other than biomedical, contributing to the literature.

Double Parallelogram Lifting Mechanism (DPLM) is a compact and stable lifting mechanism with a large extension range widely adopted in robot designs. Rubber bands and springs are often installed on the DPLM to lighten the motors' load and maintain its height, yet the installation positions are often obtained through trial and error. This project aims at finding the optimal rubber band installation positions for DPLM using modeling and optimization techniques. A mathematical model which describes the forces and moments acting on all the linkages of DPLM was derived based on the conditions for the static equilibrium and verified with a 3D simulation software. A genetic algorithm (GA) was implemented to optimize rubber band installation positions, which managed to find solutions with the overall root-mean-square- error (RMSE) of the net moment less than 2 for 2 to 6 rubber bands. A further statistical analysis of 50000 random rubber band samples showed that installing rubber bands in triangles is the best solution with the overall lowest RMSE. A test was conducted with a prototype of the DPLM and the results were consistent with our model and optimization. This project derived and verified a mathematical model for the DPLM, and found the optimal way and positions to install rubber bands. The results of this project provides a theoretical basis for controlling DPLM with rubber bands, allowing it to be further adopted in industrial robots that require repetitive lifting and lowering such as inspection robots and aerial work platforms.

常見模式生物檢測化學環境壓力後無法重複使用。本研究探討對環境變化敏感的大生熊蟲抗化學環境壓力機制，評估其作為重複使用模式生物可行性。得知多數大生熊蟲於硝酸鹽、酸鹼值改變與殺蟲劑環境壓力下仍能活動或隱生。以亞甲藍簡易染色可確認化學環境壓力下大生熊蟲是否受傷害，如體表角質層被破壞會導致完全染色。分析大生熊蟲於常見硝酸鹽環境壓力下體內脂質含量、總蛋白質單體表現量與總抗氧化能力，推測出大生熊蟲對抗硝酸鹽環境壓力機制：1.藉由> 20 kDa持續性活化蛋白抗硝酸鹽環境壓力。2.活動大生熊蟲增加體內脂質含量隔絕環境硝酸鹽。3.隱生大生熊蟲以抗氧化系統降低硝酸鹽產生的氧化壓力傷害。以上結果得知大生熊蟲具潛能檢測常見化學環境壓力並作為重複檢測之模式生物。未來將持續評估大生熊蟲可檢測的化學環境壓力並為人類健康把關。

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.

在第 屆科展作品（中華民國第 屆中小學科學展覽會換心手術）有給定了一個新的名詞(頂心三角形)：平面上給定△ABC及一點D，分別以A、B、C三頂點為圓心，¯DA、¯DB、¯DC為半徑畫圓，三圓交於三點E、F、G，再以三交點E、F、G為頂點作△EFG，則新△EFG稱為△ABC在D點的頂心三角形，本篇作品主要探討原三角形與其頂心三角形邊長與面積比例關係，並試著利用這些關係求出頂心線以及其他相關性質。 在我們的作品中，我們求出頂心三角形的三邊長為2¯AD sin⁡∠ CAB、2¯BD sin⁡∠ ABC、2¯CD sin⁡∠ BCA，也就是說在原三角形為任意三角形，可以得出頂心三角形的邊長與原三角形之間的邊長關係，我們再進一步利用邊長關係求出頂心三角形對原三角形的面積以及面積比例。我們還發現，當D點在原三角形的外接圓上時，頂心三角形會退化為一直線，稱為頂心線，而此頂心線會通過原三角形的垂心是本篇作品最重要的發現。

Two years ago, I attended a robot contest, in which one of the missions required the robot to follow the pedestrian to complete the task. At that time, I used their demo program to complete the task. Not long after, I found two main issues: 1. The program follows the closest point read by the depth camera, which if I walk close to a wall next to, the robot may likely ‘follow’ the wall. 2. Not to mention if another pedestrian crosses between the robot and the target. Regarding these two issues, I decided to improve it. We’ve designed a procedure of using YOLO Object Detection and Person re-identification to re-identify the target for continuous following.

The use of brine shrimp nauplii to test for the overall toxicity of sediment samples is proposed. Brine shrimp nauplii were cultured with different concentrations of heavy metals, including chromium (III), copper (II), nickel, lead and zinc, and organic pollutants, including triclosan, oxybenzone, octinoxate and bisphenol A. The brine shrimp nauplii were observed under a dissection microscope to determine the death rate. Results showed that brine shrimp nauplii are more sensitive to copper, cadmium, bisphenol A and oxybenzone. The LC50 (24h) are 55.5, 24.9, 5.6 and 2.7 ppm respectively. Zinc is likely to have synergistic toxic effect with nickel or lead. The synergistic toxic effects of other heavy metals and organic pollutants should be confirmed with further investigations. Brine shrimp nauplii were treated with extracts from sediment samples collected from the oyster culture zone of the Deep Bay, namely Pak Nei, Sha Kiu Tsuen and Hang Hau Tsuen. The sediment samples were extracted with neutral sodium acetate to dissolve the exchangeable heavy metal ions and some organic pollutants. The death rate of brine shrimp nauplii treated with the sediment extract of Hang Hau Tsuen was similar to 1 ppm PBA. It was also about 10 to 20% higher than that of the other two sites (Pak Nei and Sha Kiu Tsuen). Since Hang Hau Tsuen is closer to the residential area and Lau Fau Shan Seafood Market than the other two sites, its sediment sample is likely to have a higher level of environmental pollutants. The results suggest that brine shrimp nauplii may be used as a biomarker to monitor the environmental changes in the overall level of pollutants in sediment samples.

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.