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Joint UAV trajectory and communication design with heterogeneous multi-agent reinforcement learning

Science China(Information Sciences) 2024年第3期67卷 225-245页

作者： Xuanhan ZHOU Jun XIONG Haitao Zhao Xiaoran LIU Baoquan REN Xiaochen ZHANG Jibo WEI hao yin College of Electronic Science and Technology National University of Defense Technology Systems Engineering Institute Academy of Military Sciences PLA

Unmanned aerial vehicles(UAVs) are recognized as effective means for delivering emergency communication services when terrestrial infrastructures are unavailable. This paper investigates a multiUAV-assisted communication system, where we jointly optimize UAVs’ trajectories, user association, and ground users(GUs)’ transmit power to maximize a defined fairness-weighted throughput metric. Owing to the dynamic nature of UAVs, this problem has to be solved in real time. However, the problem’s non-convex and combinatorial attributes pose challenges for conventional optimization-based algorithms, particularly in scenarios without central controllers. To address this issue, we propose a multi-agent deep reinforcement learning(MADRL) approach to provide distributed and online solutions. In contrast to previous MADRLbased methods considering only UAV agents, we model UAVs and GUs as heterogeneous agents sharing a common objective. Specifically, UAVs are tasked with optimizing their trajectories, while GUs are responsible for selecting a UAV for association and determining a transmit power level. To learn policies for these heterogeneous agents, we design a heterogeneous coordinated QMIX(HC-QMIX) algorithm to train local Q-networks in a centralized manner. With these well-trained local Q-networks, UAVs and GUs can make individual decisions based on their local observations. Extensive simulation results demonstrate that the proposed algorithm outperforms state-of-the-art benchmarks in terms of total throughput and system fairness.

关键词： unmanned aerial vehicle (UAV) trajectory design resource allocation multi-agent deep reinforcement learning (MADRL) heterogeneous agents

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Extracellular vesicles from human urine-derived stem cells delay aging through the transfer of PLAU and TIMP1

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1166-1186页

作者： Shanshan Rao Zehui He Zun Wang hao yin Xiongke Hu Yijuan Tan Tengfei Wan hao Zhu Yi Luo Xin Wang Hongming Li Zhenxing Wang Xinyue Hu Chungu Hong Yiyi Wang Mingjie Luo Wei Du Yuxuan Qian Siyuan Tang Hui Xie Chunyuan Chen Department of Orthopedics Movement System Injury and Repair Research CenterXiangya HospitalCentral South UniversityChangsha 410008China Hunan Key Laboratory of Angmedicine Changsha 410008China Xiangya School of Nursing Central South UniversityChangsha 410013China Department of Pediatric Orthopedics Hunan Children’s HospitalUniversity of South ChinaChangsha 410007China Department of Respiratory Medicine Xiangya HospitalCentral South UniversityChangsha 410008China School of Nursing Xinjiang Medical UniversityUrumqiXinjiang 830000China Department of Rehabilitation Xiangya HospitalCentral South UniversityChangsha 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410008China

Aging increases the risks of various diseases and the vulnerability to death.Cellular senescence is a hallmark of aging that contributes greatly to aging and aging-related diseases.This study demonstrates that extracellular vesicles from human urine-derived stem cells(USC-EVs)efficiently inhibit cellular senescence in vitro and in vivo.The intravenous injection of USC-EVs improves cognitive function,increases physical fitness and bone quality,and alleviates aging-related structural changes in different organs of senescence-accelerated mice and natural aging mice.The anti-aging effects of USC-EVs are not obviously affected by the USC donors’ages,genders,or health status.Proteomic analysis reveals that USC-EVs are enriched with plasminogen activator urokinase(PLAU)and tissue inhibitor of metalloproteinases 1(TIMP1).These two proteins contribute importantly to the anti-senescent effects of USC-EVs associated with the inhibition of matrix metalloproteinases,cyclin-dependent kinase inhibitor 2A(P16INK4a),and cyclin-dependent kinase inhibitor 1A(P21cip1).These findings suggest a great potential of autologous USC-EVs as a promising anti-aging agent by transferring PLAU and TIMP1 proteins.

关键词： Extracellular vesicles Urine-derived stem cells Cellular senescence Anti-aging PLAU TIMP1 Senescence-accelerated mice Natural aging mice

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Insights into rapid screening and molecular mechanism of novel Rosa roxburghii seeds pancreatic lipase/cholesterol esterase inhibitory peptides: A combined in silico and in vitro perspective

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Food Science and Human Wellness 2024年

作者： hao yin Jiangxiong Zhu Yu Zhong Danfeng Wang Yun Deng Linnan Yang Lutao Gao Yongli Jiang Department of Food Science & Technology Shanghai Jiao Tong University Shanghai Jiao Tong University Yunnan (Dali) Research Institute School of Big Data Yunnan Agricultural University Faculty of Food Science and Engineering Kunming University of Science and Technology

Rosa roxburghii seeds are by-products of Rosa roxburghii processing， and their protein hydrolysates (RTSPHs) were found to possess a variety of biological activities. This study aimed to rapidly identify pancreatic lipase (PL) and cholesterol esterase (CE) inhibitory peptides in Rosa roxburghii seeds protein (RTSPHs) and to elucidate their molecular mechanisms by combining peptidomics and virtual screening. The simulated intestinal environment worsened the peptide's inhibition of PL but catalyzed the inhibition of CE. The fraction less than 3 kDa in RTSPHs was found to have the highest PL/CE inhibitory activity， among which 17 promising inhibitory peptides were identified and screened by peptidomics and virtual screening. LFCMH， RIPAGSPF， and YFRPR showed good inhibitory abilities against both PL and CE. Molecular docking showed that peptides inhibited PL and CE mainly by hydrogen bonding and hydrophobic interactions with residues in the active site and surface loop. Inhibition kinetic revealed that the peptides were competitive and mixed-type inhibitors of PL/CE. Further， the three peptides， LFCMH， RIPAGSPF， and YFRPR， could effectively inhibit 3T3-L1 preadipocytes differentiation， increase high-density lipoprotein cholesterol content and decrease low-density lipoprotein cholesterol content. This study suggests that combining peptidomics with virtual screening is an effective strategy for rapid screening of PL/CE inhibitory peptides.

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Analysis Aspects of Ricci Flow on Conical Surfaces

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Acta Mathematica Sinica,English Series 2022年第5期38卷 807-857页

作者： hao yin School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026P.R.China

In this paper,we establish a framework for the analysis of linear parabolic equations on conical surfaces and use them to study the conical Ricci flow.In particular,we prove the long time existence of the conical Ricci flow for general cone angle and show that this solution has the optimal regularity,namely,the time derivatives of the conformal factor are bounded and for each fixed time,the conformal factor has an explicit asymptotic expansion near the cone points.

关键词： Ricci flow conical singularity

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One-step synthesis of FeO(OH)nanoparticles by electric explosion of iron wire underwater

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Defence Technology（防务技术） 2022年第1期18卷 133-139页

作者： hao yin Xin Gao Peng-wan Chen Insitute of Systems Engineering China Acaderry of Engineering PhysicsMianyang.Sichuan 612900.China State Key Laboratory of Explosion Science and Technology Beijing Ins titute of Technology Beijing100081.China

In this study,we investigated electric explosion of iron wire in distilled water with different energy input adjusted by charging voltage.The as-prepared samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS),showing the presence of iron and multiple iron-based compounds oxides with contents influenced by the experimental conditions.In particular,pure FeO(OH)nanoparticles were obtained using electric explosion of iron wire with energy input of 1125 J at charging voltage of 15 kV.Analysis of discharge current and resistive voltage data indicate that the high energy input induced bystrong plasma discharge at high charging voltage is a key factor to form FeO(OH).This study presents a one-step method to synthesize FeO(OH)nanoparticles using electric explosion of iron wire.

关键词： Electric wire explosion Plasma tunnel Nanopartides FeO(OH)

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Co-Frequency Interference Analysis and Avoidance Between NGSO Constellations: Challenges, Techniques, and Trends

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China Communications 2023年第7期20卷 1-14页

作者： Yuanzhi He Yuan Li hao yin Institute ofSystemsEngineering AMSPLABeijing100141China

In recent years,as giant satellite constellations grow rapidly worldwide,the co-existence between constellations has been widely concerned.In this paper,we overview the co-frequency interference(CFI)among the giant non-geostationary orbit(NGSO)constellations.Specifically,we first summarize the CFI scenario and evaluation index among different NGSO constellations.Based on statistics about NGSO constellation plans,we analyse the challenges in mitigation and analysis of CFI.Next,the CFI calculation methods and research progress are systematically sorted out from the aspects of interference risk analysis framework,numerical calculation and link construction.Then,the feasibility of interference mitigation technologies based on space,frequency domain isolation,power control,and interference alignment mitigation in the NGSO mega-constellation CFI scenario are further sorted out.Finally,we present promising directions for future research in CFI analysis and CFI avoidance.

关键词： co-frequency existence analysis method overview interference avoidance

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Multi-Objective Deep Reinforcement Learning Based Time-Frequency Resource Allocation for Multi-Beam Satellite Communications

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China Communications 2022年第1期19卷 77-91页

作者： Yuanzhi He Biao Sheng hao yin Di Yan yingchao Zhang School of systems science and engineering Sun Yat-Sen UniversityGuangzhou 100876China Institute of Systems Engineering AMSPLABeijing 100141China

Resource allocation is an important problem influencing the service quality of multi-beam satellite communications.In multi-beam satellite communications, the available frequency bandwidth is limited, users requirements vary rapidly, high service quality and joint allocation of multi-dimensional resources such as time and frequency are required. It is a difficult problem needs to be researched urgently for multi-beam satellite communications, how to obtain a higher comprehensive utilization rate of multidimensional resources, maximize the number of users and system throughput, and meet the demand of rapid allocation adapting dynamic changed the number of users under the condition of limited resources, with using an efficient and fast resource allocation algorithm.In order to solve the multi-dimensional resource allocation problem of multi-beam satellite communications, this paper establishes a multi-objective optimization model based on the maximum the number of users and system throughput joint optimization goal, and proposes a multi-objective deep reinforcement learning based time-frequency two-dimensional resource allocation(MODRL-TF) algorithm to adapt dynamic changed the number of users and the timeliness requirements. Simulation results show that the proposed algorithm could provide higher comprehensive utilization rate of multi-dimensional resources,and could achieve multi-objective joint optimization,and could obtain better timeliness than traditional heuristic algorithms, such as genetic algorithm(GA)and ant colony optimization algorithm(ACO).

关键词： multi-beam satellite communications time-frequency resource allocation multi-objective optimization deep reinforcement learning

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Downregulation of Serum PTEN Expression in Mercury-Exposed Population and PI3K/AKT Pathway-Induced Inflammation

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Biomedical and Environmental Sciences 2024年第4期37卷 354-366页

作者： MEI Peng DING En Min yin hao Yang DING Xue Xue WANG Huan WANG Jian Feng HAN Lei ZHANG Heng Dong ZHU Bao Li School of Public Health Nanjing Medical UniversityNanjing 210000JiangsuChina Institute of Occupational Disease Prevention Jiangsu Province Center for Disease Prevention and ControlNanjing 21000JiangsuChina Suzhou Center for Disease Prevention and Control Suzhou 215004JiangsuChina Center for Global Health School of Public HealthNanjing Medical UniversityNanjing 210000JiangsuChina

Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological mechanisms.Methods Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation. Hg-exposed cell models and PTEN lowexpression models were established in vitro using 293T cells. PTEN gene expression was assessed using qRT-PCR, and Western blotting was used to measure PTEN, AKT, and PI3K protein levels. IL-6 expression was determined by ELISA.Results Combined findings from gene expression microarray analysis, bioinformatics, and population expansion validation indicated significant downregulation of the PTEN gene in the high-concentration Hg exposure group. In the Hg-exposed cell model(25 and 10 μmol/L), a significant decrease in PTEN expression was observed, accompanied by a significant increase in PI3K, AKT, and IL-6 expression.Similarly, a low-expression cell model demonstrated that PTEN gene knockdown led to a significant decrease in PTEN protein expression and a substantial increase in PI3K, AKT, and IL-6 levels.Conclusion This is the first study to report that Hg exposure downregulates the PTEN gene, activates the PI3K/AKT regulatory pathway, and increases the expression of inflammatory factors, ultimately resulting in kidney inflammation.

关键词： PTEN Occupational mercury exposure Occupational health PI3K/AKT pathway 293T cell IL-6

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Amelioration of ethanol-induced oxidative stress and alcoholic liver disease by in vivo RNAi targeting Cyp2e1

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药学学报:英文版 2023年第9期13卷 3906-3918页

作者： Yalan Wang Qiubing Chen Shuang Wu Xinyu Sun Runting yin Zhen Ouyang hao yin Yuan Wei School of Pharmacy Jiangsu UniversityZhenjiang 212013China Department of Urology Frontier Science Centre for Immunology and MetabolismMedical Research InstituteZhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Department of Pulmonary and Critical Care Medicine Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Pathology Zhongnan Hospital of Wuhan UniversityWuhan 430071China RNA Institute Wuhan UniversityWuhan 430072China Wuhan Research Centre for Infectious Diseases and Cancer Chinese Academy of Medical SciencesWuhan 430010China

Alcoholic liver disease(ALD)results from continuous and heavy alcohol consumption.The current treatment strategy for ALD is based on alcohol withdrawal coupled with antioxidant drug intervention,which is a long process with poor efficacy and low patient compliance.Alcohol-induced CYP2E1 upregulation has been demonstrated as a key regulator of ALD,but CYP2E1 knockdown in humans was impractical,and pharmacological inhibition of CYP2E1 by a clinically relevant approach for treating ALD was not shown.In this study,we developed a RNAi therapeutics delivered by lipid nanoparticle,and treated mice fed on Lieber-DeCarli ethanol liquid diet weekly for up to 12 weeks.This RNAi-based inhibition of Cyp2e1 expression reduced reactive oxygen species and oxidative stress in mouse livers,and contributed to improved ALD symptoms in mice.The liver fat accumulation,hepatocyte inflammation,and fibrosis were reduced in ALD models.Therefore,this study suggested the feasibility of RNAi targeting to CYP2E1 as a potential therapeutic tool to the development of ALD.

关键词： Alcoholic liver disease RNAi Lipid nanoparticle Cyp2e1 Reactive oxygen species Oxidative stress Lipogenesis Lipometabolism

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Diagnosing anomalous characteristics of atmospheric water cycle structure during seasonal-scale drought events:A case study in middle and lower reaches of Yangtze River

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Water Science and Engineering 2022年第2期15卷 103-113页

作者： Hai He Rui Cao Zhi-yong Wu Yuan Li hao yin Fei Yuan College of Hydrology and Water Resources Hohai UniversityNanjing 210098China

Anomalous characteristics of the atmospheric water cycle structure are highly significant to the mechanisms of seasonal-scale meteorological droughts.They also play an important role in the identification of indicative predictors of droughts.To better understand the causes of seasonal meteorological droughts in the middle and lower reaches of the Yangtze River(MLRYR),characteristics of the atmospheric water cycle structure at different drought stages were determined using standardized anomalies.The results showed that the total column water vapor(TCWV)was anomalously low during drought occurrence periods.In contrast,there were no anomalous signals at the drought persistence and recovery stages in the MLRYR.Moreover,there was no significant temporal correlation between the TCWV anomaly and seasonal-scale drought index(the 3-month standardized precipitation index(SPI_(3))).During drought events,water vapor that mainly originated from the Bay of Bengal was transported southwest of the MLRYR.Meanwhile,the anomalous signal of water vapor transport was negative at the drought appearance stage.At the drought persistence stage,the negative anomalous signal was the most significant.Water vapor flux divergence in the MLRYR showed significant positive anomalous signals during drought events,and the signal intensity shifted from an increasing to a decreasing trend at different drought stages.In addition,a significant positive correlation existed between the anomaly of water vapor flux divergence and regional SPI_(3).Overall,water vapor flux divergence is more predictive of droughts in the MLRYR.

关键词： Water vapor transport Water vapor flux divergence Standardized anomalies Seasonal-scale drought process Middle and lower reaches of Yangtze River

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