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Antibacterial and cytotoxic metabolites produced by Streptomyces tanashiensis BYF-1.2 isolated from Odontotermes formosanus

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Chinese Journal of Natural Medicines 2024年第9期22卷 822-830页

作者： WU Jun SONG tao {1. Le HUANG Zhongdi HUANG Fang YIN Caiping {1. Shuxiang LIU Xinhua {1. Yinglao School of Life Science Anhui Agricultural UniversityHefei 230036China School of Pharmacy Anhui Medical UniversityHefei 230036China

Chemical investigations of the termite-associated Streptomyces tanashiensis BYF-1.2 resulted in the discovery of four novel alkaloid derivatives: vegfrecines A and B(1.and 2), exfoliazone A(3), and venezueline H(7), in addition to nine known metabolites(4-6, 8-1.). The structures of these compounds were elucidated through comprehensive spectroscopic analysis and comparison with existing literature data. Antibacterial assays revealed that viridomycin A(1.) exhibited potent antibacterial activity against Staphylococcus aureus, with a zone of inhibition(ZOI) of 1..67 mm, in comparison to a ZOI of 1..67 mm for the positive control gentamicin sulfate. Viridomycin A(1.) showed moderate activity against Micrococcus tetragenus and Pseudomonas syringae pv. actinidae, with ZOI values of 1..50 and 1..33 mm, respectively, which were inferior to those of gentamicin sulfate(34.67 and 24.00mm). Viridomycin F(1.) also exhibited moderate antibacterial effects against S. aureus, M. tetragenus, and P. syringae pv. actinidae,with ZOI values of 8.33, 1..50, and 1..83 mm, respectively. Cytotoxicity assays demonstrated that viridobruunine A(5), exfoliazone(6), viridomycin A(1.), and X-1.881.(1.) exhibited significant cytotoxicity against human malignant melanoma(A375), ovarian cancer(SKOV-3), and gastric cancer(MGC-803) cell lines, with IC_(50) values ranging from 4.61.to 1..28 μmol·L^(-1.. Furthermore, bioinformatic analysis of the complete genome of S. tanashiensis suggested a putative biosynthetic gene cluster(BGC) responsible for the production of compounds 1.1.. These findings indicate that the secondary metabolites of insect-associated S. tanashiensis BYF-1.2hold promise as potential sources of novel antibacterial and anticancer agents.

关键词： Odontotermes formosanus Streptomyces tanashiensis Alkaloid Cytotoxic activity Antibacterial activity Biosynthetic pathway

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Dynamic access task scheduling of LEO constellation based on space-based distributed computing

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Journal of Systems Engineering and Electronics 2024年第4期35卷 842-854页

作者： LIU Wei JIN Yifeng zhang Lei GAO Zihe {1. Ying Institute of Telecommunication and Navigation Satellites China Academy of Space TechnologyBeijing 100094China Innovation Center of Satellite Communication System China National Space AdministrationBeijing 100094China

A dynamic multi-beam resource allocation algorithm for large low Earth orbit(LEO)constellation based on on-board distributed computing is proposed in this *** allocation is a combinatorial optimization process under a series of complex constraints,which is important for enhancing the matching between resources and requirements.A complex algorithm is not available because that the LEO on-board resources is *** proposed genetic algorithm(GA)based on two-dimen-sional individual model and uncorrelated single paternal inheri-tance method is designed to support distributed computation to enhance the feasibility of on-board application.A distributed system composed of eight embedded devices is built to verify the algorithm.A typical scenario is built in the system to evalu-ate the resource allocation process,algorithm mathematical model,trigger strategy,and distributed computation *** to the simulation and measurement results,the proposed algorithm can provide an allocation result for more than 1.00 tasks in 1. s and the success rate is more than 91.in a typical *** response time is decreased by 40%com-pared with the conditional GA.

关键词： beam resource allocation distributed computing low Earth obbit(LEO)constellation spacecraft access task scheduling

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An Overview of Sequential Approximation in Topology Optimization of Continuum Structure

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 43-67页

作者： Kai Long Ayesha Saeed Jinhua zhang Yara Diaeldin Feiyu Lu {1. {1. Yuhua Li Pengwen Sun Jinshun Yan State Key Laboratory of Alternate Electrical Power Systemwith Renewable Energy Sources North China Electric Power UniversityBeijing102206China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing100124China New Energy and Energy Storage Division China Southern Power Grid Technology Co.Ltd.Guangzhou510080China School of Mechanical Engineering Inner Mongolia University of TechnologyHohhot010051China College of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot010051China

This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum *** structures,commonly encountered in engineering applications,often involve complex objective and constraint functions that cannot be readily expressed as explicit functions of the design *** a result,sequential approximation techniques have emerged as the preferred strategy for addressing a wide array of topology optimization *** the past several decades,topology optimization methods have been advanced remarkably and successfully applied to solve engineering problems incorporating diverse physical *** comparison to the large-scale equation solution,sensitivity analysis,graphics post-processing,etc.,the progress of the sequential approximation functions and their corresponding optimizersmake sluggish ***,particularly novices,pay special attention to their difficulties with a particular ***,this paper provides an overview of sequential approximation functions,related literature on topology optimization methods,and their *** from optimality criteria and sequential linear programming,the other sequential approximate optimizations are introduced by employing Taylor expansion and intervening *** addition,recent advancements have led to the emergence of approaches such as Augmented Lagrange,sequential approximate integer,and non-gradient approximation are also *** highlighting real-world applications and case studies,the paper not only demonstrates the practical relevance of these methods but also underscores the need for continued exploration in this ***,to provide a comprehensive overview,this paper offers several novel developments that aim to illuminate potential directions for future research.

关键词： Topology optimization sequential approximate optimization convex linearization method ofmoving asymptotes sequential quadratic programming

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A strategy for strengthening chaotic mixing of dual shaft eccentric mixers by changing non-Newtonian fluids kinetic energy distribution

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Chinese Journal of Chemical Engineering 2024年第5期69卷 122-134页

作者： Songsong Wang Tong Meng Qian zhang Changyuan {1. Yundong Wang Zequan Li Zuohua Liu School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing 400044China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

Efficiently modulating the velocity distribution and flow pattern of non-Newtonian fluids is a critical challenge in the context of dual shaft eccentric mixers for process intensification,posing a significant barrier for the existing ***,this work reports a convenient strategy that changes the kinetic energy to controllably regulate the flow patterns from radial flow to axial *** showed that the desired velocity distribution and flow patterns could be effectively obtained by varying the number and structure of baffles to change kinetic energy,and a more uniform velocity distribution,which could not be reached normally in standard baffle dual shaft mixers,was easily ***,a comparative analysis of velocity and shear rate distributions is employed to elucidate the mechanism behind the generation of flow patterns in various dual-shaft eccentric ***,there is little difference in the power number of the laminar flow at the same Reynolds number,meaning that the baffle type has no effect on the power consumption,while the power number of both unbaffle and U-shaped baffle mixing systems decreases compared with the standard baffle mixing system in the transition ***,at the same rotational condition,the dimensionless mixing time of the U-shaped baffle mixing system is 1..3%and 7.9%shorter than that of the standard baffle and the unbaffle mixing system,respectively,which shows the advantage of the U-shaped baffle in stirring rate.

关键词： Dual shaft “U-shaped”baffle Flow pattern Mixing time Power demand

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Yolk-shell FeSe_(2)@CoSe_(2)/FeSe_(2) heterojunction as anode materials for sodium-ion batteries with high rate capability and stability

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Journal of Materials Science & Technology 2024年第5期172卷 185-195页

作者： Liuyang zhang Bicheng Zhu Difa Xu Zibao Qian Ping Xie {1. Liu Jiaguo Yu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China Hunan Key Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410022China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Sodium-ion batteries are promising candidates for large-scale grid storage systems and other *** foremost advantage derives from superior environmental credentials,enhanced safety as well as lower raw material costs than lithium-ion *** is still challenging to explore desirable anode *** this study,FeSe_(2)@CoSe_(2)/FeSe_(2),with a yolk-shell structure was prepared by ion exchange and *** FeSe_(2)@CoSe_(2)/FeSe_(2)prepared as anode material for sodiumion batteries exhibits excellent rate capability due to the synergistic effect of bimetallic selenides and the interfacial effect of the ***,it delivers high performance(51. mAh g^(-1.at 0.2 A g^(-1.),superior rate capa-bility(90%retention at 5 A g^(-1.),and good long-time cycling stability(78%capacity retention after 1.00 cycles at a high current density of 2 A g^(-1.).The optimized sodiumion full cell with FeSe_(2)@CoSe_(2)/FeSe_(2)as the anode and Na 3 V 2(PO 4)3 as the cathode still demonstrates excellent ***,a ca-pacity of 272 mAh g^(-1.(at 1.A g^(-1.)within the operating voltage from 1.to 3.8 V can be *** work illustrates the potential of bimetallic selenides with heterostructures for performance enhancement of sodium-ion batteries.

关键词： Cobalt-iron selenide Heterojunctions Sodium storage Anode material Full battery

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Learning to Branch in Combinatorial Optimization With Graph Pointer Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 157-169页

作者： Rui Wang Zhiming Zhou Kaiwen Li tao {1. Ling Wang Xin Xu Xiangke Liao IEEE the Xiangjiang Laboratory and the College of Systems Engineering National University of Defense TechnologyChangsha 410073China the Institute of Automation Chinese Academy of SciencesBeijing 100190China the College of Systems Engineering National University of Defense TechnologyChangsha 410073 the Hunan Key Laboratory of Multi-Energy System Intelligent Interconnection Technology Changsha 410073China the Department of Automation Tsinghua UniversityBeijing 100084China the College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China the College of Computer Science and Technology National University of Defense TechnologyChangsha 410073China

Traditional expert-designed branching rules in branch-and-bound(B&B) are static, often failing to adapt to diverse and evolving problem instances. Crafting these rules is labor-intensive, and may not scale well with complex *** the frequent need to solve varied combinatorial optimization problems, leveraging statistical learning to auto-tune B&B algorithms for specific problem classes becomes attractive. This paper proposes a graph pointer network model to learn the branch rules. Graph features, global features and historical features are designated to represent the solver state. The graph neural network processes graph features, while the pointer mechanism assimilates the global and historical features to finally determine the variable on which to branch. The model is trained to imitate the expert strong branching rule by a tailored top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. It also outperforms state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances.

关键词： Branch-and-bound(B&B) combinatorial optimization deep learning graph neural network imitation learning

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Overcoming the Limits of Cross-Sensitivity:Pattern Recognition Methods for Chemiresistive Gas Sensor Array

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Nano-Micro Letters 2024年第12期16卷 285-341页

作者： Haixia Mei Jingyi Peng tao Wang Tingting Zhou Hongran Zhao Tong {1. Zhi Yang Key Lab Intelligent Rehabil&Barrier Free Disable(Ministry of Education) Changchun UniversityChangchun 130022People’s Republic of China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China National Key Laboratory of Advanced Micro and Nano Manufacture Technology Department of Micro/Nano ElectronicsSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012People’s Republic of China

As information acquisition terminals for artificial olfaction,chemiresistive gas sensors are often troubled by their cross-sensitivity,and reducing their cross-response to ambient gases has always been a difficult and important point in the gas sensing *** recognition based on sensor array is the most conspicuous way to overcome the cross-sensitivity of gas *** is crucial to choose an appropriate pattern recognition method for enhancing data analysis,reducing errors and improving system reliability,obtaining better classification or gas concentration prediction *** this review,we analyze the sensing mechanism of crosssensitivity for chemiresistive gas *** further examine the types,working principles,characteristics,and applicable gas detection range of pattern recognition algorithms utilized in gas-sensing ***,we report,summarize,and evaluate the outstanding and novel advancements in pattern recognition methods for gas *** the same time,this work showcases the recent advancements in utilizing these methods for gas identification,particularly within three crucial domains:ensuring food safety,monitoring the environment,and aiding in medical *** conclusion,this study anticipates future research prospects by considering the existing landscape and *** is hoped that this work will make a positive contribution towards mitigating cross-sensitivity in gas-sensitive devices and offer valuable insights for algorithm selection in gas recognition applications.

关键词： Pattern recognition Sensor array Chemiresistive gas sensor Cross-sensitivity Artificial olfactory

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Bioinspired metal-organic framework nanozyme reinforced with thermosensitive hydrogel for regulating inflammatory responses in Parkinson’s disease

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Nano Research 2024年第2期17卷 858-865页

作者： Xiaowan Fan tao {1. Xin Ding Yushuo Gu Qing Li Wei Jiang Kelong Fan Nanozyme Medical Center Academy of Medical ScienceZhengzhou UniversityZhengzhou 450001China Department Central-China Branch of National Center for Cardiovascular DiseasesHean Cardiovascular Disease CenterFuwai Central-China HospitalCentral China Fuwai Hospital of Zhengzhou UniversityZhengzhou 450046China Application Center for Precision Medicine the Second Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China CAS Engineering Laboratory for Nanozyme Key Laboratory of Protein and Peptide PharmaceuticalsInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China Department of General Surgery Strategic Support Force Medical CenterBeijing 100101China Department of Anesthesiology Pain and Perioperative MedicineThe First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Parkinson’s disease(PD)is a prevalent neurodegenerative disorder accompanied by movement disorders and neuroinflammatory ***-inflammatory intervention to regulate oxidative stress in the brain is beneficial for managing ***,traditional natural antioxidants have failed to meet the clinical treatment demands due to insufficient activity and ***,Cu-doping zeolite imidazolate framework-8(ZIF-8)nanozyme is designed to simulate Cu/Zn superoxide dismutase(SOD)by biomimetic *** nanozyme composite is then integrated into thermosensitive hydrogel(poly(lactic-co-glycolic acid)-poly(ethylene glycol)-poly(lactic-co-glycolic acid)(PLGA-PEG-PLGA))to form an effective antioxidant system(Cu-ZIF@Hydrogel).The thermosensitive hydrogel incorporating nanozymes demonstrate distinct viscoelastic properties aimed at enhancing local nanozyme adhesion,prolonging nanozyme retention time,and modulating antioxidant activity,thus significantly improving the bioavailability of *** the cellular and animal levels of PD,we find that Cu-ZIF@Hydrogel bypass the blood-brain barrier and efficiently accumulate in the nerve ***,the Cu-ZIF@Hydrogel significantly alleviate the PD’s behavioral and pathological symptoms by reducing the neuroinflammatory levels in the lesion ***,the hydrogel-incorporating nanozyme system holds great potential as a simple and reliable avenue for managing PD.

关键词： bioinspired nanozyme thermosensitive hydrogel Parkinson’s disease oxidative stress neuroinflammatory

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Progress in enhancing the remediation performance of microbial fuel cells for contaminated groundwater

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Journal of Environmental Sciences 2024年第11期145卷 28-49页

作者： Yuan Liang Dong Yu Hui Ma tao {1. Yi Chen Naveed Akbar Shengyan Pu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil&Water Pollution Chengdu University of TechnologyChengdu 610059China

Microbial fuel cells(MFCs)have become more prevalent in groundwater remediation due to their capacity for power generation,removal of pollution,ease of assembly,and low secondary *** is currently being evaluated for practical application in an effort to eliminate groundwater ***,a considerable majority of research was conducted in *** the operational circumstances including anaerobic characteristics,pH,and temperature vary at different *** addition,the complexity of contaminants and the positioning of MFCs significantly affect remediation *** the aforementioned factors into consideration,this reviewsummarizes a bibliography on the application of MFCs for the remediation of groundwater contamination during the last ten decades and assesses the impact of environmental conditions on the treatment *** design of the reactor,including configuration,dimensions,electrodes,membranes,separators,and target contaminants are *** review aims to provide practical guidance for the future application of MFCs in groundwater remediation.

关键词： Microbial fuel cells(MFCs) Contaminated groundwater Groundwater remediation Biodegradation

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Microstructure Features and the Macroscopic Acoustic Behavior of Gassy Silt in the Yellow River Delta

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Journal of Ocean University of China 2024年第2期23卷 371-382页

作者： LIU tao GUO Zhenqi {1. Yan WU Chen LIU Lele DENG Shenggui Laboratory for Marine Geology Pilot National Laboratory for Marine Science and TechnologyQingdao 266061China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China College of Civil Engineering Anhui Jianzhu UniversityHefei 230601China The Key Laboratory of Gas Hydrate Ministry of Natural ResourcesQingdao Institute of Marine GeologyQingdao 266071China College of Marine Geosciences Key Laboratory of Submarine Geosciences and ProspectingOcean University of ChinaQingdao 266100China

The morphological changes in isolated bubbles in gassy silt play a critical role in the microscopic structures between soil particles and bubbles and macroscopic physical *** on X-ray CT scanning experiments under various vertical loads(four levels),self-designed acoustic macro experiments,and a series of formula revisions to the macro-air-bearing silt sound-velocity prediction model,this paper discusses the macro-and micro-scale features of gassy silts from the Yellow River *** samples consisted of different proportions of silt from the Yellow River Delta and porous media,and they were used to form two types of aerosol silts with initial gas contents of 4.23%and 7.67%.The results show that the air bubble content and external load considerably affect the microstructural parameters and acoustic behavior of gassy silt in the Yellow River *** macroscopic sound velocity showed a linear positive correlation with vertical load and relation to microstructural parameters in varying manners and *** on the traditional Biot-Stoll acoustic model,the gas-phase medium coefficient was introduced for the proper calculation and prediction of the sound velocity of air-bearing *** errors of the overall prediction varied between 5.6%and 9.6%.

关键词： gassy silt vertical load microstructure parameters bubble vibration Biot-Stoll acoustic model

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