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Recorded recurrent deep reinforcement learning guidance laws for intercepting endoatmospheric maneuvering missiles

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Defence Technology（防务技术） 2024年第1期31卷 457-470页

作者： Xiaoqi Qiu peng lai Changsheng Gao Wuxing Jing Department of Aerospace Engineering Harbin Institute of TechnologyHarbin150001China Shanghai Electro-Mechanical Engineering Institute Shanghai Academy of Spaceflight TechnologyShanghai201100China

This work proposes a recorded recurrent twin delayed deep deterministic(RRTD3)policy gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with uncertainties and observation noise.The attack-defense engagement scenario is modeled as a partially observable Markov decision process(POMDP).Given the benefits of recurrent neural networks(RNNs)in processing sequence information,an RNN layer is incorporated into the agent’s policy network to alleviate the bottleneck of traditional deep reinforcement learning methods while dealing with POMDPs.The measurements from the interceptor’s seeker during each guidance cycle are combined into one sequence as the input to the policy network since the detection frequency of an interceptor is usually higher than its guidance frequency.During training,the hidden states of the RNN layer in the policy network are recorded to overcome the partially observable problem that this RNN layer causes inside the agent.The training curves show that the proposed RRTD3 successfully enhances data efficiency,training speed,and training stability.The test results confirm the advantages of the RRTD3-based guidance laws over some conventional guidance laws.

关键词： Endoatmospheric interception Missile guidance Reinforcement learning Markov decision process Recurrent neural networks

Revealing the role of CCoAOMT1: fine-tuning bHLH transcription factors for optimal anther development

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Science China(Life Sciences) 2024年第3期67卷 565-578页

作者： Zesen lai Jianzheng Wang Ying Fu Menghan Wang Hong Ma Shiqing peng Fang Chang State Key Laboratory of Genetic Engineering Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering and Institute of Biodiversity SciencesInstitute of Plant BiologySchool of Life SciencesFudan UniversityShanghai 200438China School of Tropical Agriculture and Forestry Agriculture-Rural Affairs and Rural RevitalizationHainan UniversityHaikou 570228China Key Laboratory of Biology and Genetic Resources of Tropical Crops Ministry of AgricultureInstitute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikou 571101China Department of Biology Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPA 16802USA

The tapetum,a crucial innermost layer encompassing male reproductive cells within the anther wall,plays a pivotal role in normal pollen development.The transcription factors (TFs) bHLH010/089/091 redundantly facilitate the rapid nuclear accumulation of DYSFUNCTIONAL TAPETUM 1,a gatekeeper TF in the tapetum.Nevertheless,the regulatory mechanisms governing the activity of bHLH010/089/091 remain unknown.In this study,we reveal that caffeoyl coenzyme A O-methyltransferase 1 (CCoAOMT1) is a negative regulator affecting the nuclear localization and function of bHLH010 and bHLH089,probably through their K259 site.Our findings underscore that CCoAOMT1 promotes the nuclear export and degradation of bHLH010 and bHLH089.Intriguingly,elevated CCoAOMT1 expression resulted in defective pollen development,mirroring the phenotype observed in bhlh010 bhlh089 mutants.Moreover,our investigation revealed that the K259A mutation in the bHLH089 protein disrupted its translocation from the nucleus to the cytosol and impeded its degradation induced by CCoAOMT1.Importantly,transgenic plants with the probHLH089::bHLH089^(K259A)construct failed to rescue proper pollen development or gene expression in bhlh010 bhlh089 mutants.Collectively,these findings emphasize the need to maintain balanced TF homeostasis for male fertility.They firmly establish CCoAOMT1 as a pivotal regulator that is instrumental in achieving equilibrium between the induction of the tapetum transcriptional network and ensuring appropriate anther development.

关键词： anther development nuclear localization bHLH O-methyltransferase transcription factor homeostasis

Manganese oxide and derivative-modified materials in advanced oxidation processes:A review of modification enhancement and activation mechanisms

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Chinese Chemical Letters 2024年第3期35卷 40-51页

作者： Si Sun shuang Song shuai Yang Yong-Li He Yang Shi peng Zhou Zhao-kun Xiong Yang Liu Heng Zhang Ye Du Chuan-shu He Bo lai State Key Laboratory of Hydraulics and Mountain River Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Sino-German Centre for Water and Health Research Sichuan UniversityChengdu 610065China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaSichuanChengdu 610054China

Manganese oxides(MNO_(x)),as low-toxicity and high-abundance catalysts,have been demonstrated to hold great promise for application in advanced oxidation processes(AOPs).However,further application of this material is restricted due to its unsatisfactory oxidant activation efficiency.Fortunately,recently remarkable research on deep activation mechanisms and modification of MNO_(x)have been undertaken to improve its reactivity.Herein,modification enhancement mechanisms of MNO_(x)to efficiently degrade various organic contaminants were discussed and highlighted,including metal doping,coupling with other metal oxides,composite with carbonaceous material,and compounding with other support.The activation mechanisms of different MNO_(x)and derivative-modified material(such as doped MNO_(x),metal oxide-MNO_(x)hybrids,and MNO_(x)-carbonaceous material hybrids)were summarized in great details,which was specifically categorized into both radical and non-radical pathways.The effects of pH,inorganic ions,and natural organic matter on degradation reactions are also discussed.Finally,future research directions and perspectives are presented to provide a clear interpretation on the MNO_(x)initiated AOPs.

关键词： Manganese oxide Derivative-modified materials Modification enhancement mechanisms Advanced oxidation process Activation mechanism

T-tube bridging fistula jejunal anastomosis for treatment of pancreatic lumbar dorsal fistula after necrotizing pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 428-430页

作者： Su-lai Liu Guo-Guang Li Wei Cheng Chuang peng Ying-Hui Song Department of Hepatobiliary Surgery Hunan Provincial People’s Hospital/The First Affiliated Hospital of Hunan Normal UniversityChangsha 410000China

Infectious pancreatic necrosis causes external pancreatic fistula in some patients.Generally,external pancreatic fistula requires fistula-gastric and/or intestinal anastomosis,and digestive endoscopic interventional treatment[1–3].It is especially difficult to treat external pancreatic fistulas with small fistulas where the external fistula is located in the lower back.The common treatment is to remove the body and tail of the pancreas and the spleen.This operation is very traumatic.A new pancreatic fistula may still occur at the pancreatic stump.The above operations may lead to unnecessary resection of the spleen,colon injury and other complications.In order to solve this problem,we innovatively used T-tube bridging fistula jejunal anastomosis plus continuous negative pressure suction to treat three cases of external pancreatic fistulas in the lower back,and all of them achieved good results.

关键词： fistula anastomosis spleen

Volume-complementary bipolar layered oxide enables stable symmetric sodium-ion batteries

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Nano Research 2024年第5期17卷 4125-4133页

作者： Bo peng Feng Wang Nazir Ahmad lai Yu Shenghua Chen Genqiang Zhang School of Materials Science and Engineering Key Laboratory of Efficient Conversion and Solid-state Storage of Hydrogen and Electricity of Anhui ProvinceAnhui University of TechnologyMa’anshan 243002China Hefei National Research Center for Physical Sciences at the Microscale Chinese Academy of Sciences(CAS)Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China National Innovation Platform(Center)for Industry-Education Integration of Energy Storage Technology School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

The commercialization of sodium-ion batteries is based on developing low-cost,highly stable,and safe cathode and anode electrodes.However,the promising hard carbon anode and layered oxide cathode suffer from low sodium-embedded potential near 0.1 V and severe phase transitions,which cause safe problem and short lifespan,respectively.Herein,we design a low-strain bipolar P2-Na_(0.7)Ni_(0.25)Fe_(0.2)Ti_(0.55)O_(2) to solve the mentioned obstacles,whereas(Ni,Fe)and Ti provide charge compensation when it is used as cathode and anode,respectively.It is revealed that the bipolar layered oxide undergoes solid-solution reaction when used as cathode or anode,and exhibits volume-complementary feature in a sodium-ion full-cell,as identified by in-situ X-ray diffraction.Remarkably,the safe symmetric sodium-ion full-cell exhibits excellent cyclic stability with 91.7%capacity retention after 200 cycles.This work will provide a new horizon for designing safe and stable sodium-ion batteries.

关键词： sodium-ion batteries bipolar layered oxides solid-solution reaction volume complementation symmetric battery

26-electrons redox-active polyoxovanadate clusters for aqueous zincion batteries

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Nano Research 2024年第5期17卷 4047-4054页

作者： Yimin Xing Wen Yan Haiyang Wu peng Huang Chao Wang Chao lai School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116China

Aqueous zinc-ion batteries(ZIBs)are attaining increasing attention for their high safety and low cost.Despite significant progresses in realizing high-performance cathode material for ZIBs,simultaneously endowing them with high capacity and fast-charging capability,the long-term cycling stability remains a major unsolved challenge.In this work,a polyoxovanadate cluster of(NH_(4))_(8)[V_(19)O_(41)(OH)_(9)]·11H_(2)O(NOV)is defined as a cathode material for ZIBs that contains mixed-valence vanadium sites(V^(4+)and V^(5+)).A maximum of 26 electrons can be accommodated in one[V_(19)O_(41)(OH)_(9)]^(8-){V_(19)O_(50)}cluster,contributing to the high theoretical specific capacity of 328 mA·h·g^(-1).The Ti_(3)C_(2)T_(x) MXene nanosheets are incorporated into NOV with the help of ionic liquid(IL)linkers to restrain the dissolution of vanadium species and facilitate electron transport across the electrode.The interfacial bonding,anion exchange,and electrostatic interactions among NOV and MXene are provided by IL liquid.The nanohybrid of NOV-IL-MXene endows excellent contact between MXene and NOV,thereby enhanced charge transfer is observed at interface.Subsequently,the as-synthesized NOV-IL-MXene cathodes exhibit high discharge capacity of 413 mA·h·g^(-1) at 0.2 A·g^(-1) even at high mass loading of 5.2 mg·cm^(-2),remarkable rate performance of 182 mA·h·g^(-1) at 10 A·g^(-1),and impressive cycling stability of 94%capacity retention after 2000 cycles.This work opens up new opportunities to develop advanced polyoxovanadate hybrid cathodes for low-cost and high-performance aqueous ZIBs.

关键词： polyoxovanadate MXene composite materials cathodes zinc-ion batteries

In vivo imaging reveals a synchronized correlation among neurotransmitter dynamics during propofol and sevoflurane anesthesia

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Zoological Research 2024年第3期45卷 679-690页

作者： Gao-Lin Qiu Li-Jun peng peng Wang Zhi-lai Yang Ji-Qian Zhang Hu Liu Xiao-Na Zhu Jin Rao Xue-Sheng Liu Department of Anesthesiology First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China

General anesthesia is widely applied in clinical practice.However,the precise mechanism of loss of consciousness induced by general anesthetics remains unknown.Here,we measured the dynamics of five neurotransmitters,includingγ-aminobutyric acid,glutamate,norepinephrine,acetylcholine,and dopamine,in the medial prefrontal cortex and primary visual cortex of C57BL/6 mice through in vivo fiber photometry and genetically encoded neurotransmitter sensors under anesthesia to reveal the mechanism of general anesthesia from a neurotransmitter perspective.Results revealed that the concentrations of γ-aminobutyric acid,glutamate,norepinephrine,and acetylcholine increased in the cortex during propofol-induced loss of consciousness.Dopamine levels did not change following the hypnotic dose of propofol but increased significantly following surgical doses of propofol anesthesia.Notably,the concentrations of the five neurotransmitters generally decreased during sevoflurane-induced loss of consciousness.Furthermore,the neurotransmitter dynamic networks were not synchronized in the non-anesthesia groups but were highly synchronized in the anesthetic groups.These findings suggest that neurotransmitter dynamic network synchronization may cause anesthetic-induced loss of consciousness.

关键词： General anesthesia Loss of consciousness In vivo neurotransmitter imaging Medial prefrontal cortex Primary visual cortex

Metallurgy and Solidification Microstructure Control of Fusion-Based Additive Manufacturing Fabricated Metallic Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 29-53页

作者： Qiang Li Xing-Ran Li Bai-Xin Dong Xiao-Long Zhang Shi-Li shu Feng Qiu lai-Chang Zhang Zhi-Hui Zhang Key Laboratory of Bionic Engineering(Ministry of Education) and College of Bionic Science and EngineeringJilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and EngineeringJilin UniversityChangchun130025China School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130025China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

The metal-based additive manufacturing(AM),also referred to as metal 3D printing,has drawn particular interest because it enables direct creation,aided by computationally-directed path design,of intricate components with site-specific compositions and geometrical requirements as well as low buy-to-fly ratios.During the last two decades,the objective of this revolutionary technology has been shifting from only“rapid prototyping”to advanced manufacturing of special high-end products or devices,which,in many aspects,outperform conventional manufacturing technologies.For fusion-based AM,significant progress has been achieved in understanding the processing window of macroscopic scales,non-equilibrium metallurgy of mesoscale scales,and grain evolution of microscopic scales.Although the versatile capacity of AM facilitates new avenues for discovering advanced materials and structures,their potential has still not been fully explored.Given the unique non-equilibrium solidification during the AM process,coarse columnar grains with strong textures are usually developed along the build direction,which downgrades the mechanical performance.To push the limits of this digital manufacturing,this review attempts to provide in-depth and comprehensive overviews of the recent progress in understanding the evolution and control of the as-built microstructure that has been made recently and the challenges encountered during the AM process.

关键词： Additive manufacturing Temperature field Microstructure control Nanoparticles Functionally graded materials

Experimental and numerical simulation study on the erosion behavior of the elbow of gathering pipeline in shale gas field

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Petroleum Science 2024年第2期21卷 1257-1274页

作者： En-Bin Liu Shen Huang Ding-Chao Tian lai-Min Shi Shan-Bi peng He Zheng Petroleum Engineering School Southwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Natural Gas Sales Center Natural Gas BranchSinopecChongqing400023China Zhejiang Zheneng Natural Gas Operation Co. Ltd.Hangzhou 310000ZhejiangChina School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu 610500SichuanChina Louisiana Tech Univ Trenchless Technol Ctr599 Dan Reneau DrRustonLA71270USA Southwest Oil and Gas Field Branch Natural Gas Research Institute Chengdu 610213SichuanChina

During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.

关键词： Shale gas Gas gathering pipeline Elbow Erosion CFD