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270 results on '"Sun, Yaqi"'

2. HiBid: A Cross-Channel Constrained Bidding System with Budget Allocation by Hierarchical Offline Deep Reinforcement Learning

Author

Wang, Hao, Tang, Bo, Liu, Chi Harold, Mao, Shangqin, Zhou, Jiahong, Dai, Zipeng, Sun, Yaqi, Xie, Qianlong, Wang, Xingxing, and Wang, Dong

Subjects
Computer Science - Machine Learning, Computer Science - Computer Science and Game Theory
Abstract

Online display advertising platforms service numerous advertisers by providing real-time bidding (RTB) for the scale of billions of ad requests every day. The bidding strategy handles ad requests cross multiple channels to maximize the number of clicks under the set financial constraints, i.e., total budget and cost-per-click (CPC), etc. Different from existing works mainly focusing on single channel bidding, we explicitly consider cross-channel constrained bidding with budget allocation. Specifically, we propose a hierarchical offline deep reinforcement learning (DRL) framework called ``HiBid'', consisted of a high-level planner equipped with auxiliary loss for non-competitive budget allocation, and a data augmentation enhanced low-level executor for adaptive bidding strategy in response to allocated budgets. Additionally, a CPC-guided action selection mechanism is introduced to satisfy the cross-channel CPC constraint. Through extensive experiments on both the large-scale log data and online A/B testing, we confirm that HiBid outperforms six baselines in terms of the number of clicks, CPC satisfactory ratio, and return-on-investment (ROI). We also deploy HiBid on Meituan advertising platform to already service tens of thousands of advertisers every day.

Published
2023

3. Parallel Computing Based Solution for Reliability-Constrained Distribution Network Planning

Author

Sun, Yaqi, Wu, Wenchuan, Lin, Yi, Huang, Hai, and Chen, Hao

Subjects
Electrical Engineering and Systems Science - Systems and Control
Abstract

The main goal of distribution network (DN) expansion planning is essentially to achieve minimal investment constrained with specified reliability requirements. The reliability-constrained distribution network planning (RcDNP) problem can be cast an instance of mixed-integer linear programming (MILP) which involves ultra-heavy computation burden especially for large scale DNs. In this paper, we propose a parallel computing-based acceleration algorithm for solve RcDNP problem. The RcDNP is decomposed into a backbone grid and several lateral grid problems with coordination. Then a parallelizable augmented Lagrangian algorithm with acceleration strategy is developed to solve the coordination planning problems. In this method, the lateral grid problems are solved in parallel through coordinating with the backbone grid planning problem. To address the presence of nonconvexity, Gauss-Seidel iteration is adopted on the convex hull of the feasible region constructed by the decomposition method. Under mild conditions, the optimality and convergence of this algorithm is proven. The numerical tests show the proposed method can significantly reduce the computation time and make the RcDNP applicable for real-world problems.

Published
2023

4. Design and Implementation of a Cinema Work Optimization and Data Analysis System Based on Intelligent Recognition Technology

Author

Sun, Yaqi, Bu, Jiayi, Tang, Peng, Ou, Yangze, Liang, Xiaoman, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Zhang, Yonghong, editor, Qi, Lianyong, editor, Liu, Qi, editor, Yin, Guangqiang, editor, and Liu, Xiaodong, editor

Published
2024
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5. Target Spatial Positioning System Based on Dual Cameras

Author

Sun, Yaqi, Tang, Peng, Bu, Jiayi, Lin, Mugang, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Zhang, Yonghong, editor, Qi, Lianyong, editor, Liu, Qi, editor, Yin, Guangqiang, editor, and Liu, Xiaodong, editor

Published
2024
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6. A Fair Federated Learning Framework With Reinforcement Learning

Author

Sun, Yaqi, Si, Shijing, Wang, Jianzong, Dong, Yuhan, Zhu, Zhitao, and Xiao, Jing

Subjects
Computer Science - Machine Learning
Abstract

Federated learning (FL) is a paradigm where many clients collaboratively train a model under the coordination of a central server, while keeping the training data locally stored. However, heterogeneous data distributions over different clients remain a challenge to mainstream FL algorithms, which may cause slow convergence, overall performance degradation and unfairness of performance across clients. To address these problems, in this study we propose a reinforcement learning framework, called PG-FFL, which automatically learns a policy to assign aggregation weights to clients. Additionally, we propose to utilize Gini coefficient as the measure of fairness for FL. More importantly, we apply the Gini coefficient and validation accuracy of clients in each communication round to construct a reward function for the reinforcement learning. Our PG-FFL is also compatible to many existing FL algorithms. We conduct extensive experiments over diverse datasets to verify the effectiveness of our framework. The experimental results show that our framework can outperform baseline methods in terms of overall performance, fairness and convergence speed.

Published
2022

8. DESTA: A Framework for Safe Reinforcement Learning with Markov Games of Intervention

Author

Mguni, David, Islam, Usman, Sun, Yaqi, Zhang, Xiuling, Jennings, Joel, Sootla, Aivar, Yu, Changmin, Wang, Ziyan, Wang, Jun, and Yang, Yaodong

Subjects
Computer Science - Machine Learning
Abstract

Reinforcement learning (RL) involves performing exploratory actions in an unknown system. This can place a learning agent in dangerous and potentially catastrophic system states. Current approaches for tackling safe learning in RL simultaneously trade-off safe exploration and task fulfillment. In this paper, we introduce a new generation of RL solvers that learn to minimise safety violations while maximising the task reward to the extent that can be tolerated by the safe policy. Our approach introduces a novel two-player framework for safe RL called Distributive Exploration Safety Training Algorithm (DESTA). The core of DESTA is a game between two adaptive agents: Safety Agent that is delegated the task of minimising safety violations and Task Agent whose goal is to maximise the environment reward. Specifically, Safety Agent can selectively take control of the system at any given point to prevent safety violations while Task Agent is free to execute its policy at any other states. This framework enables Safety Agent to learn to take actions at certain states that minimise future safety violations, both during training and testing time, while Task Agent performs actions that maximise the task performance everywhere else. Theoretically, we prove that DESTA converges to stable points enabling safety violations of pretrained policies to be minimised. Empirically, we show DESTA's ability to augment the safety of existing policies and secondly, construct safe RL policies when the Task Agent and Safety Agent are trained concurrently. We demonstrate DESTA's superior performance against leading RL methods in Lunar Lander and Frozen Lake from OpenAI gym., Comment: arXiv admin note: text overlap with arXiv:2103.09159

Published
2021

11. Human defensin-inspired discovery of peptidomimetic antibiotics.

Author

Luo, Gan, Zhang, Jue, Wang, HanBin, Sun, YaQi, Cheng, BaoLi, Xu, ZhiPeng, Zhang, Yan, Li, Hui, Lu, WuYuan, Nemeth, Elizabeta, Ganz, Tomas, and Fang, XiangMing

Subjects
antimicrobial resistance, defensins, infections, peptidomimetic antibiotics, Anti-Bacterial Agents, Defensins, Drug Discovery, Gram-Negative Bacteria, Humans, Microbial Sensitivity Tests, Molecular Structure, Peptidomimetics, Structure-Activity Relationship
Abstract

SignificanceWe report the development of peptidomimetic antibiotics derived from a natural antimicrobial peptide, human α-defensin 5. By engaging multiple bacterial targets, the lead compound is efficacious in vitro and in vivo against bacteria with highly inducible antibiotic resistance, promising a useful therapeutic agent for the treatment of infections caused by antibiotic-resistant bacteria.

Published
2022

13. Traffic Signal Light Recognition Based on Transformer

Author

Ou, Yangze, Sun, Yaqi, Yu, Xiaozhong, Yun, Liuqing, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Liu, Qi, editor, Liu, Xiaodong, editor, Cheng, Jieren, editor, Shen, Tao, editor, and Tian, Yuan, editor

Published
2022
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14. Traffic Sign Recognition System Based on YOLOv5

Author

Zhang, Lin, Sun, Yaqi, Chen, Wenli, Liang, Xiaoman, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Liu, Qi, editor, Liu, Xiaodong, editor, Cheng, Jieren, editor, Shen, Tao, editor, and Tian, Yuan, editor

Published
2022
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15. Epidemic Real-Time Monitor Based on Spark Streaming Real-Time Computing Algorithm

Author

Yang, Jiaxin, Sun, Yaqi, Lian, Xiaoman, He, Xiaoyang, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Liu, Qi, editor, Liu, Xiaodong, editor, Chen, Bo, editor, Zhang, Yiming, editor, and Peng, Jiansheng, editor

Published
2022
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16. Baby Expression Recognition System Design and Implementation Based on Deep Learning

Author

Zhu, Xuanying, Sun, Yaqi, Liu, Qingyun, Xiang, Jin, Lin, Mugang, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Liu, Qi, editor, Liu, Xiaodong, editor, Chen, Bo, editor, Zhang, Yiming, editor, and Peng, Jiansheng, editor

Published
2022
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18. Investigating the functional and structural modulation of carboxysomes in Synechococcus elongatus PCC7942

Author

Sun, Yaqi and Liu, Luning

Abstract

Organelle formation and compartmentalisation within eukaryotic and prokaryotic cells provide the structural foundation for modulation of metabolic reactions in space and time. Bacterial microcompartments (BMCs) are self-assembling organelles widespread among bacterial phyla. By physically sequestering specific enzymes key for metabolic processes from the cytosol, these organelles play essential roles in carbon fixation, microbial ecology and pathogenesis. Carboxysomes serve as the key CO2-fixing machinery in all cyanobacteria and some chemoautotrophs. The β-carboxysomes in the cyanobacterium Synechococcus elongatus PCC7942 (Syn7942) have been extensively characterised as the model carboxysomes. In Chapter 1, general research background centralised on carboxysomes was summarised. In Chapter 2, material and methods adopted in this thesis were documented. From Chapter 3 to Chapter 5, I addressed specific topics on functional and structural modulation of carboxysomes in Syn7942. In Chapter 6, I concluded the findings in previous chapters and showed the perspectives following this project. In Chapter 3, we used fluorescence tagging and live-cell confocal fluorescence imaging to explore the biosynthesis and subcellular localisation of β-carboxysomes within Syn7942 cell in response to light variation. We demonstrated that β-carboxysome synthesis on cellular level is re-modulated in response to increasing light intensity, thereby enhancing the carbon fixation activity of the cell. Inhibition of photosynthetic electron flow impairs the accumulation of carboxysomes, indicating close coordination between β-carboxysome biogenesis and photosynthetic electron transport. Likewise, the spatial organisation of carboxysomes in the cell correlates with the redox state of photosynthetic electron transport chain. In Chapter 4, we used live-cell single-molecule fluorescence microscopy, coupled with confocal and electron microscopy, to decipher the absolute protein stoichiometry and organisational variability of single β-carboxysomes in Syn7942 cell. I find that the protein stoichiometry, diameter, cellular localisation and mobility pattern of carboxysomes in cells depend sensitively on the microenvironmental levels of CO2 and light intensity during cell growth, revealing cellular strategies of dynamic regulation. In Chapter 5, I documented the biosynthesis and organisation of carboxysomes under diurnal dark-light cycles compare to constant light in Syn7942. We found the reoccurring carboxysome distribution changes and rhythmic carbon fixation capacities in diurnal condition. Also, we documented the localisation, enzymatic activity as well as the quantity of carboxysomes in circadian null background to provide preliminary evidence of circadian control in carboxysome biogenesis. The findings in this thesis provide essential knowledge for us to modulate the β-carboxysome biosynthesis and function in cyanobacteria. Furthermore, improving our understanding of carboxysome assembly principles will aid rational design of functional metabolic factories in heterologous organisms for metabolic engineering using synthetic biology.

Published
2019
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27. Gender Identification for Coloring Black and White Portrait with cGan

Author

Liu, Qingyun, Lin, Mugang, Sun, Yaqi, Zhang, Feng, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Liu, Qi, editor, Liu, Xiaodong, editor, Shen, Tao, editor, and Qiu, Xuesong, editor

Published
2021
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28. Design and Implementation of Handwritten Digit Recognition Based on K-Nearest Neighbor Algorithm

Author

Wang, Ying, Liu, Qingyun, Sun, Yaqi, Zhang, Feng, Zhu, Yining, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Liu, Qi, editor, Liu, Xiaodong, editor, Shen, Tao, editor, and Qiu, Xuesong, editor

Published
2021
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29. Research on Algorithms for Setting up Advertising Platform Based on Minimum Weighted Vertex Covering

Author

Wang, Ying, Sun, Yaqi, Liu, Qinyun, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Liu, Qi, editor, Liu, Xiaodong, editor, Li, Lang, editor, Zhou, Huiyu, editor, and Zhao, Hui-Huang, editor

Published
2021
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38. A Blessing or a Curse? Highway Connection and the Entry of Polluting Firms in China.

Author

Meng, Xuechen, Sun, Yaqi, and Xu, Xiaoshu

Abstract

We investigate how highway connections influenced the entry of polluting firms based on panel data from 257 Chinese prefectures from 1998 to 2012. We also investigate the heterogeneity and influencing channels. We use the generalized difference-in-difference method as a tool in the empirical analysis. We have three main findings. First, highway connections increased the entry of polluting firms by 54.5 percent. Second, the heterogeneity analysis shows that this effect is mainly caused by prefectures on provincial borders, prefectures in central China, and prefectures with more than 1 million residents in urban districts. Third, highway connections reduced the concern about environmental protection by local governments of prefectures on provincial boundaries but increased concern about local governments of prefectures in interior regions. The concern about employment increased regardless of a prefecture's location in a province. These results indicate that less developed regions, i.e., those on provincial boundaries, valued the benefit of job creation for welfare improvement more than the harm of pollution. Hence, they intentionally reduced environmental regulation to induce polluting firms' entry. Our results provide new and insightful insights into the transition of economic development to a sustainable path, especially in developing countries. [ABSTRACT FROM AUTHOR]

Published
2024
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44. Conjugated Polymer/Recombinant Escherichia coliBiohybrid Systems for Photobiocatalytic Hydrogen Production

Author

Yang, Ying, Zwijnenburg, Martijn A., Gardner, Adrian M., Adamczyk, Sylwia, Yang, Jing, Sun, Yaqi, Jiang, Qiuyao, Cowan, Alexander J., Sprick, Reiner Sebastian, Liu, Lu-Ning, and Cooper, Andrew I.

Abstract

Biohybrid photocatalysts are composite materials that combine the efficient light-absorbing properties of synthetic materials with the highly evolved metabolic pathways and self-repair mechanisms of biological systems. Here, we show the potential of conjugated polymers as photosensitizers in biohybrid systems by combining a series of polymer nanoparticles with engineered Escherichia colicells. Under simulated solar light irradiation, the biohybrid system consisting of fluorene/dibenzo [b,d]thiophene sulfone copolymer (LP41) and recombinant E. coli(i.e., a LP41/HydA BL21 biohybrid) shows a sacrificial hydrogen evolution rate of 3.442 mmol g–1h–1(normalized to polymer amount). It is over 30 times higher than the polymer photocatalyst alone (0.105 mmol g–1h–1), while no detectable hydrogen was generated from the E. colicells alone, demonstrating the strong synergy between the polymer nanoparticles and bacterial cells. The differences in the physical interactions between synthetic materials and microorganisms, as well as redox energy level alignment, elucidate the trends in photochemical activity. Our results suggest that organic semiconductors may offer advantages, such as solution processability, low toxicity, and more tunable surface interactions with the biological components over inorganic materials.

Published
2024
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