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MADRL-based UAV swarm non-cooperative game under incomplete information

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Chinese Journal of Aeronautics 2024年第6期37卷 293-306页

作者： Ershen WANG Fan LIU Chen HONG Jing GUO lin ZHAO Jian XUE ning he School of Electronic and Information Engineering Shenyang Aerospace UniversityShenyang 110136China College of Robotics Beijing Union UniversityBeijing 100101China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China College of Smart City Beijing Union UniversityBeijing 100101China

Unmanned Aerial Vehicles(UAVs)play increasing important role in modern *** this paper,considering the incomplete observation information of individual UAV in complex combat environment,we put forward an UAV swarm non-cooperative game model based on Multi-Agent Deep Reinforcement Learning(MADRL),where the state space and action space are constructed to adapt the real features of UAV swarm air-to-air *** multi-agent particle environment is employed to generate an UAV combat scene with continuous observation *** recently popular MADRL methods are compared extensively in the UAV swarm noncooperative game model,the results indicate that the performance of Multi-Agent Soft Actor-Critic(MASAC)is better than that of other MADRL methods by a large *** swarm employing MASAC can learn more effective policies,and obtain much higher hit rate and win *** under different swarm sizes and UAV physical parameters are also performed,which implies that MASAC owns a well generalization ***,the practicability and convergence of MASAC are addressed by investigating the loss value of Q-value networks with respect to individual UAV,the results demonstrate that MASAC is of good practicability and the Nash equilibrium of the UAV swarm non-cooperative game under incomplete information can be reached.

关键词： UAV swarm Reinforcement learning Deep learning Multi-agent Non-cooperative game Nash equilibrium

Umbilical cord mesenchymal stem cell exosomes alleviate necrotizing enterocolitis in neonatal mice by regulating intestinal epithelial cells autophagy

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World Journal of Stem Cells 2024年第6期16卷 728-738页

作者： lin Zhu Lu he Wu Duan Bo Yang ning Li Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Division of Endocrinology Department of Internal MedicineQilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Shenzhen Research Institute of Shandong University Shenzhen 518000Guangdong ProvinceChina Institute of Organ Transplantation Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Department of Physical Education Heze UniversityHeze 274015Shandong ProvinceChina

BACKGROUND Necrotizing enterocolitis(NEC)is a severe gastrointestinal disease that affects premature *** mounting evidence supports the therapeutic effect of exosomes on NEC,the underlying mechanisms remain *** To investigate the mechanisms underlying the regulation of inflammatory response and intestinal barrier function by umbilical cord mesenchymal stem cell(UCMSCs)exosomes,as well as their potential in alleviating NEC in neonatal *** NEC was induced in 5-d-old C57BL/6 pups through hypoxia and gavage feeding of formula containing lipopolysaccharide(LPS),after which the mice received human UCMSC exosomes(hUCMSC-exos).The control mice were allowed to breastfeed with their *** tissues were collected from the mice and analyzed by histopathology and *** tissues were collected from NEC neonates and analyzed by *** biology and cell culture approaches were employed to study the related mechanisms in intestinal epithelial *** We found that autophagy is overactivated in intestinal epithelial cells during NEC,resulting in reduced expression of tight junction proteins and an increased inflammatory *** ability of hUCMSC-exos to ameliorate NEC in a mouse model was dependent on decreased intestinal *** also showed that hUCMSC-exos alleviate the inflammatory response and increase migration ability in intestinal epithelial cells induced by *** These results contribute to a better understanding of the protective mechanisms of hUCMSC-exos against NEC and provide a new theoretical and experimental foundation for NEC *** findings also enhance our understanding of the role of the autophagy mechanism in NEC,offering potential avenues for identifying new therapeutic targets.

关键词： Necrotizing enterocolitis Autophagy Umbilical cord mesenchymal stem cell Exosomes Intestinal epithelial cell Intestinal barrier function

Flocking Effects of the Stochastic Cucker-Smale System with Noise

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Journal of Systems Science & Complexity 2024年第5期37卷 1978-1994页

作者： HAN ning GE Bin LI lin School of Mathematical Sciences Harbin Engineering UniversityHarbin 150001China

In this paper,the flocking behavior of a Cucker-Smale model with a leader and noise is studied in a finite *** authors present a Cucker-Smale system with two nonlinear controls for a complex network with stochastic synchronization in *** on the finite-time stability theory of stochastic differential equations,the sufficient conditions for the flocking of stochastic systems in a finite time are obtained by using the Lyapunov function ***,the numerical simulation of the particle system is carried out for the leader and noise,and the correctness of the results is verified.

关键词： Cucker-Smale model flocking behavior leader noise

Hypoxia-inducible factor-1α induces the epithelial-mesenchymal transition of human prostatecancer cells

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Chinese Medical Journal 2006年第9期119卷 713-718页

作者： LUO Yong he Da-lin ning Liang SheN Shu-lin LI Lei LI Xiang Department of Urology First Hospital of Xi＇an Jiaotong University Xi＇an 710061 China

Background Hypoxia-inducible factor- 1α （HIF- 1α） is a transcriptional factor that could improve the stimulation of angiogenesis and the metabolic adaptation of tumor cells to hypoxia. A recent study showed that HIF- 1α could induce colon cancer cells epithelial-mesenchymal transition （EMT）. However, no evidence indicates a similar correlation in human prostate cancer cells. This study was designed to evaluate the effect of HIF- 1α over-expression on the EMT in human prostate cancer cells. Methods We selected the appropriate cell line for HIF- 1α induction from those EMT negative prostate cell lines through vimentin gene detection by RT-PCR. As the result, LNCaP cell line is the best one for further experiment. LNCaP cells were transfected with recombinant plasmid pcDNA3.1 （-）/HIF- 1α and pcDNA3.1 （-） control vector by Lipofectamine 2000 system. The positive cell colonies were confirmed by indirect immunofluorescence labeling. Then Transwell polycarbonate filter was used to analyze the invasive potency. The expression of EMT associated proteins, E-cadherin and vimentin, was detected by Western blotting. Results Among four of the EMT negative cell lines, LNCaP was the only one expressed the vimentin gene but not the associated protein. The expression level of HIF- 1α in LNCaP/HIF- 1α was distinctly higher than that in LNCaP/pcDNA3.1 and LNCaP. The cell numbers of LNCaP/HIF- 1α that penetrated through the Transwell filter were higher than that of LNCaP/pcDNA3.1 and LNCaP. Compared with the LNCaP/pcDNA3.1 and LNCaP cells, the expression of vimentin was up-regulated in LNCaP/HIF- 1α, whereas the expression of E-cadherin was down-regulated.Conclusions Over-expression of HIF- 1α stimulates the invasion potency of human prostate carcinoma cells through EMT pathway. The expression of E-cadherin and vimentin, playing established roles in EMT, could be regulated by HIF- 1α in human prostate cancer cell line.

关键词： prostate cancer epithelial-mesenchymal transition hypoxia-inducible factor- 1α

Brazilin Actuates Ferroptosis in Breast Cancer Cells via p53/SLC7A11/GPX4 Signaling Pathway

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Chinese Journal of Integrative Medicine 2024年第11期30卷 1001-1006页

作者： he Dan TAN Xiao-ning LI lin-pei GAO Wen-hui TIAN Xue-fei ZENG Pu-hua Hunan Academy of Chinese Medicine School of Integrated Chinese and Western Medicine Hunan University of Chinese Medicine Scientific Research Department The Affiliated Hospital of Hunan Academy of Traditional Chinese Medicine Oncology Department The Affiliated Hospital of Hunan Academy of Traditional Chinese Medicine School of Traditional Chinese Medicine Hunan University of Chinese Medicine

Objective:To investigate the mechanism of induction of ferroptosis by brazilin in breast cancer ***:Breast cancer 4T1 cells were divided into 6 groups:control,brazilin 1/2 half maximal inhibitory concentration(IC50),IC50,2×IC50,erastin（10 μg/mL） and capecitabine（10 μg/mL） *** effect of brazilin on the proliferation of 4T1 cells was detected by cell counting kit-8 assay,and the treatment dose of brazilin was *** effect of brazilin on the mitochondrial morphology of 4T1 cells,and the mitochondrial damage was evaluated under electron *** levels of Fe2+,reactive oxygen species（ROS）,malondialdehyde（MDA）,glutathione（GSH） and glutathione peroxidase 4（GPX4） were estimated using various detection *** invasion and migration abilities of 4T1 cells were detected by scratch assay and transwell *** expressions levels of tumor protein p53, solute carrier family 7 member 11（SLC7A11）,GPX4 and acyl-CoA synthetase long-chain family member 4（ACSL4） proteins were quantified by Western blot ***:Compared to the control group,the 10(1/2 IC50),20(IC50) and 40(2×IC50) μg/mL brazilin,erastin,and capecitabine groups showed a significant decrease in the cell survival rate,invasion and migration abilities,GSH,SLC7A11 and GPX4 protein expression levels,and mitochondrial volume and ridge（Phe mitochondria membrane density,Fe2+,ROS and MDA levels,and p53 and ACSL4protein expression levels（Plin actuated ferroptosis in breast cancer cells,and the underlying mechanism is mainly associated with the p53/SLC7A11/GPX4 signaling pathway.

关键词： Chinese medicine brazilin breast cancer ferroptosis p53/SLC7A11/GPX4 axis

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-lin Shen Jian-Jun he Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

The Minimum Centroid Branch Spanning Tree Problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： Hao lin Cheng he School of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree T of graph G,the centroid of T is a vertex v for which the largest component of T-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree T of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly NP-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and P_(m)×P_(n),are presented.

关键词： Spanning tree optimization Centroid branch-NP-hardness Polynomial-time algorithm

Construction of algal-bacterial consortia using green microalgae Chlorella vulgaris and As(Ⅲ)-oxidizing bacteria:As tolerance and metabolomic profiling

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Journal of Environmental Sciences 2024年第5期139卷 258-266页

作者： Xiaoman he Guobing lin Jiayuan Zeng Zhaoguang Yang lin Wang College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety Central South UniversityChangsha 410083China

Bioremediation became a promising technology to resolve arsenic(As)contamination in aquatic *** monoculture such as microalgae or bacteria was sensitive to environmental disturbance and vulnerable to contamination,green microalgae Chlorella vulgaris and arsenite(As(Ⅲ))-oxidizing bacteria Pseudomonas ***11 were co-cultured to construct algal-bacterial consortia in the current *** effects of algae-bacteria(A:B)ratio and exposure As(Ⅲ)concentration on algal growth,As speciation and metabolomic profile were *** growth arrested when treated with 100 mg/L As(Ⅲ)without the co-cultured *** contrast,co-cultured with strain SMS11 significantly enhanced As tolerance in *** especially with A:B ratio of 1:*** the As(Ⅲ)in culture media of the consortia were oxidized into As(Ⅴ)on day *** of As was observed on day *** 1% and 0.5% of total As were converted into dimethylarsinic acid(DMA)after 21days cultivation when the initial concentrations of As(Ⅲ)were 1 and 10 mg/L,*** analysis was further performed to reveal the response of consortia metabolites to external As(Ⅲ).The enriched metabolomic pathways were associated with carbohydrate,amino acid and energy *** acid cycle and glyoxylate and dicarboxylate metabolism were upregulated under As stress due to their biological functions on alleviating oxidative stress and protecting *** carbohydrate and amino acid metabolisms provided precursors and potential substrates for energy production and cell protection under abiotic *** of the pathways relevant to carbohydrate or amino acid metabolism were triggered by energy requirement.

关键词： Microalgae Algal-bacterial consortia As(Ⅲ)-oxidizing bacteria Metabolomics Energy metabolism

Selective N-Methylation of N-Methylaniline with CO_(2) and H_(2) over Cu/In_(2)O_(3) Catalyst

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Chinese Journal of Chemistry 2024年第3期42卷 276-282页

作者： Huan Zheng Bo Qian lin he State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China University of Chinese Academy of Sciences Beijing100049 China

N-Methylation of amines with CO_(2) and H2 is a potential approach for CO_(2) utilization because N-methylated amines can be used as solvents and organic intermediates. In_(2)O_(3)-supported Cu (Cu/In_(2)O_(3)) acts as an effective heterogeneous catalyst for N-methylation reaction of N-methylaniline (MA) with CO_(2) and H_(2),showing higher N,N-dimethylaniline (DMA) selectivity than other supported Cu catalysts. On one hand,the dispersion of Cu can be improved by the defective In_(2)O_(3) support. On the other hand,In_(2)O_(3) support is active in the dissociative adsorption of CO_(2) through C—O bond breaking. In addition,the H_(2) dissociation ability of In_(2)O_(3) can also be enhanced by Cu. The combination of Cu and In_(2)O_(3) is effective in the activation of CO_(2),the adsorption of intermediate N-methylformanilide (MFA),the hydrogenation of MFA to DMA and the prohibition of C—N bond cleavage side reactions,thereby enhancing the reaction rate of MA conversion and the selectivity to DMA.

关键词： N-Methylation CO_(2) Cu/In_(2)O_(3) Supported catalysts heterogeneous catalysis