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Characterizing the complete mitochondrial genome of Psephenothrips eriobotryae dang&Qiao(Thysanoptera:Phlaeothripidae)with massive gene arrangement in Phlaeothripidae

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Zoological Systematics 2024年第2期49卷 116-128页

作者： Lihong dang Chengwen Li Dongxue Wang Yuxin Gao Linpeng Zhao Bin Zhang School of Biological Science&Engineering Shaanxi University of TechnologyHanzhong 723000China Engineering Research Center of Quality Improvement and Safety Control of Qinba Special Meat Products Universities of Shaanxi ProvinceHanzhong 723000China Shaanxi Changqing National Nature Reserve Changqing JiayuanNo.176Hanzhong 723000China College of Life Sciences&Technology Inner Mongolia Normal UniversityHohhot 010022China

Each species within the order Thysanoptera has a distinct mitochondrial gene order displaying a high level of gene rearrangement,particularly massive in Phlaeothripidae.To understand the evolutionary patterns of rearrangement in this family,we sequenced the complete mitochondrial genome of Psephenothrips eriobotryae,a notable potential pest of loquat trees.Its mitogenome is a circular DNA molecule(15,413 bp in size)composed of 37 genes:13 PCGs,22 tRNAs,two rRNAs,and two putative control regions(CRs).By comparing with the ancestral mitogenome of arthropods,P.eriobotryae exhibits notable gene rearrangement variations.However,it shares four conserved gene blocks with three closely related species in Phlaeothripinae.In the phylogenetic tree,P.eriobotryae was clustered with these three leaffeeding Phlaeothripinae species.The presence of more similar conserved gene blocks probably indicates a strong correlation between gene rearrangements and the phylogeny within Phlaeothripidae.Furthermore,the mitogenome of P.eriobotryae shows some characteristics:(a)two putative CRs in which CR2 is the copy of partial CR1 with 99.62%sequence similarity,and CR1 consists of two 237 bp repeat unites;(b)high A+T content of 82.6%in overall base composition;(c)trn S1 lacking a complete dihydrouridine(DHU)arm;(d)the protein coding gene,atp8 started with TTG instead of the more common ATN,while nad3 terminated by TAG rather than TAA;(e)translocations and inversions observed in fifteen of the 37 genes.

关键词： Mitogenome structure phylogenetic relationships Liothrips-lineage repeat regions

Triad-displaced ULAs configuration for non-circular sources with larger continuous virtual aperture and enhanced degrees of freedom

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Journal of Systems Engineering and Electronics 2024年第1期35卷 81-93页

作者： SHAIKH Abdul Hayee dang Xiaoyu HUANG Daqing College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Non-uniform linear array(NULA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ULAs).These characteristics play a significant role in improving the direction-of-arrival(DOA)estimation accuracy.However,most of the existing NULA geometries are primarily applicable to circular sources(CSs),while they limitedly improve the DOF and continuous virtual aperture for noncircular sources(NCSs).Toward this purpose,we present a triaddisplaced ULAs(Tdis-ULAs)configuration for NCS.The TdisULAs structure generally consists of three ULAs,which are appropriately placed.The proposed antenna array approach fully exploits the non-circular characteristics of the sources.Given the same number of elements,the Tdis-ULAs design achieves more DOF and larger hole-free co-array aperture than its sparse array competitors.Advantageously,the number of uniform DOF,optimal distribution of elements among the ULAs,and precise element positions are uniquely determined by the closed-form expressions.Moreover,the proposed array also produces a filled resulting co-array.Numerical simulations are conducted to show the performance advantages of the proposed Tdis-ULAs configuration over its counterpart designs.

关键词： direction-of-arrival(DOA)estimation sparse array non-circular source(NCS) sum co-array difference co-array degrees of freedom(DOF)

A Review on Flow Boiling of the Fluid with Lower Boiling Point in Micro-Channels

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Journal of Thermal Science 2024年第1期33卷 1-17页

作者： ZHANG Zhiqiang JIA Li dang Chao Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

With the advancement of micro machining technology,the high-heat-flux removal from miniature electronic devices and components has become an attractive topic.Flow boiling in micro-channels is an optimal form of heat transfer and has been widely employed in high-heat-flux cooling applications.This comprehensively-reviewed article focused on the available recent literatures of experimental investigation regarding the flow boiling heat transfer and unstable behaviors of the fluid with lower boiling point in micro-channels.The thermal-fluid characteristics and potential heat transfer mechanisms of low-boiling-point fluids flow boiling in different narrow passages were summarized and discussed.The literatures regarding the pressure drop and occurrence of the unstable phenomena existing in two-phase flow boiling process were also discussed.The emphasis was given to the heat transfer enhancement methods as well as instability elimination,and various methods such as modification of surface and channel flow geometries were considered.Some future researches in the field of micro-scale flow boiling were suggested.

关键词： flow boiling lower boiling point fluids mini/micro-channels instabilities enhancement suppression

Parametric formation control of multiple nanosatellites for cooperative observation of China Space Station

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Astrodynamics 2024年第1期8卷 77-95页

作者： Hao Zhou Bohan Jiao Zhaohui dang Jianping Yuan School of Astronautics Northwestern Polytechnical UniversityXi’an710072China National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an710072China

This study proposes a parametric formation control method for the cooperative observation of the China Space Station(CSS)using multiple nanosatellites.First,a simplified geometrical model of the CSS is constructed using fundamental solids,such as the capsule body and cuboid.Second,the spacecraft formation configuration for the observation mission is characterized by a three-dimensional(3D)Lissajous curve using related design parameters under the full-coverage observation requirements of specific parts,such as the CSS connecting section and collision avoidance constraints.Third,a double-layer control law is designed for each nanosatellite,in which the upper layer is a distributed observer for recognizing the target formation configuration parameters,and the lower layer is a trajectory-tracking controller to make the nanosatellite converge to its temporary target position calculated from the upper layer’s outputs.The closed-loop control stability is proven under the condition that the communication network topology of the nanosatellite cluster contains a directed spanning tree.Finally,the control method is verified by numerical simulation,where the CSS connecting section is selected as the observation target,and ten small nanosatellites are assumed to perform the cooperative observation mission.The simulation results demonstrate that the double-layer control law is robust to single-point communication failures and suitable for the accompanying missions of large space objects with multiple nanosatellites.

关键词： China Space Station(CSS) cooperative observation parametric formation 3D Lissajous curve double-layer system

QAR Data Imputation Using Generative Adversarial Network with Self-Attention Mechanism

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Big Data Mining and Analytics 2024年第1期7卷 12-28页

作者： Jingqi Zhao Chuitian Rong Xin dang Huabo Sun School of Computer Science and Technology Tiangong UniversityTianjin 300387China Institute of Aviation Safety China Academy of Civil Aviation Science and TechnologyBeijing 100028China

Quick Access Recorder(QAR),an important device for storing data from various flight parameters,contains a large amount of valuable data and comprehensively records the real state of the airline flight.However,the recorded data have certain missing values due to factors,such as weather and equipment anomalies.These missing values seriously affect the analysis of QAR data by aeronautical engineers,such as airline flight scenario reproduction and airline flight safety status assessment.Therefore,imputing missing values in the QAR data,which can further guarantee the flight safety of airlines,is crucial.QAR data also have multivariate,multiprocess,and temporal features.Therefore,we innovatively propose the imputation models A-AEGAN("A"denotes attention mechanism,"AE"denotes autoencoder,and"GAN"denotes generative adversarial network)and SA-AEGAN("SA"denotes self-attentive mechanism)for missing values of QAR data,which can be effectively applied to QAR data.Specifically,we apply an innovative generative adversarial network to impute missing values from QAR data.The improved gated recurrent unit is then introduced as the neural unit of GAN,which can successfully capture the temporal relationships in QAR data.In addition,we modify the basic structure of GAN by using an autoencoder as the generator and a recurrent neural network as the discriminator.The missing values in the QAR data are imputed by using the adversarial relationship between generator and discriminator.We introduce an attention mechanism in the autoencoder to further improve the capability of the proposed model to capture the features of QAR data.Attention mechanisms can maintain the correlation among QAR data and improve the capability of the model to impute missing data.Furthermore,we improve the proposed model by integrating a self-attention mechanism to further capture the relationship between different parameters within the QAR data.Experimental results on real datasets demonstrate that the model can reasonably impute the missing values in QAR data wi

关键词： multivariate time series data imputation self-attention Generative Adversarial Network(GAN)

Grey interpolation approach for small time-lag samples based on grey dynamic relation analysis

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Journal of Systems Engineering and Electronics 2018年第1期29卷 105-115页

作者： WANG Junjie dang yaoguo XU Ning DING Song College of Economics and Management Nanjing University of Aeronautics and Astronautics College of Management Science and Engineering Nanjing Audit University

Given a non-equidistant sequence or an equidistant series with one or more outliers, a grey interpolation approach considering the time lags is established for producing the missing data or correcting the abnormal values. To accomplish this, a new grey incidence model, called the grey dynamic incidence model GDIM(t), is constructed for determining whether the factors are effective to the known factor and what the time lag is between a useful factor and the specified sequence. Based on the results of the GDIM(t) model, two programming problems are designed to obtain the upper and lower bounds of the unknown or abnormal values which are regarded as grey numbers. The solutions based on the particle swarm optimization(PSO) for the nonlinear programming problems are given. To explain how it can be used in practice, this new grey interpolation approach is applied to correct an abnormal value in the sequence of an agriculture environment problem.

关键词： grey interpolation grey relational analysis time lags programming problems

Tailoring of a robust asymmetric aramid nanofibers/MXene aerogel film for enhanced infrared thermal camouflage and Joule heating performances

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Nano Research 2024年第3期17卷 1990-1998页

作者： Wanbin dang Wei Guo Wenting Chen Qiuyu Zhang Key Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

The development of infrared(IR)surveillance technology has led to a growing interest in thermal camouflage.However,the trade-off relationship between low IR-emissivity and thermal insulation hinders the advance of thermal camouflage materials.Herein,guided by multi-physics simulation,we show a design of asymmetric aramid nanofibers/MXene(ANF/MXene)aerogel film that realizes high-efficient thermal camouflage applications.The rationale is that the asymmetric structure contains a thermal-insulation three-dimensional(3D)network part to prevent effective heat transfer and a low IR-emissivity(~0.3)dense surface layer to suppress radiative heat emission.It is remarkable that the synergy mechanism in the topology structure contributes to over 40%reduction of target radiation temperature.Impressively,the tailored asymmetric ANF/MXene aerogel film also enables sound mechanical properties such as a Young’s modulus of 44.4 MPa and a tensile strength of 1.3 MPa,superior to most aerogel materials.It also exhibits great Joule heating performances including low driving voltage(4 V),fast thermal response(<10 s),and long-term stability,further enabling its versatile thermal camouflage applications.This work offers an innovative design concept to configure multifunctional structures for next-generation thermal management applications.

关键词： asymmetric aerogel film low infrared(IR)-emissivity thermal insulation IR thermal camouflage Joule heating performance

Molecular mechanisms of stress resistance in sorghum: Implications for crop improvement strategies

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Journal of Integrative Agriculture 2024年第3期23卷 741-768页

作者： Hongxiang Zheng Yingying dang Xianmin Diao Na Sui Shandong Provincial Key Laboratory of Plant Stress/College of life Sciences Shandong Normal UniversityJinan 250014China Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China

Abiotic stresses, such as drought, salt, extreme temperatures, and heavy metal pollution, are the main environmental factors that limit crop growth and yield. Sorghum, a C4 grass plant with high photosynthetic efficiency, can grow in adverse environmental conditions due to its excellent stress resistance characteristics. Therefore, unraveling the stress-resistance mechanism of sorghum could provide a theoretical basis for developing and cultivating various stress-resistant crops. This understanding could also help to create a conducive environment for using marginal soil in agriculture and ensuring food security. In this review, we discuss the adaptation mechanisms of sorghum under drought, salinity, temperature, and soil heavy metal stresses, the specific response to stress, the screening of sorghum-resistant germplasm, and the identification and functional analysis of the relevant genes and quantitative trait loci(QTL). In addition, we discuss the application potential of different stress-tolerant sorghum germplasms reported to date and emphasize the feasibility and potential use in developing and promoting highly stress-tolerant sorghum in marginal soil.

关键词： abiotic stress C4 plants QTL sorghum stress resistance yield stability

Cross-upgrading of biomass hydrothermal carbonization and pyrolysis for high quality blast furnace injection fuel production:Physicochemical characteristics and gasification kinetics analysis

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 268-281页

作者： Han dang Runsheng Xu Jianliang Zhang Mingyong Wang Jinhua Li State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Chemical Engineering The University of QueenslandQueensland 4072Australia

The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile content of biochar ranged from 16.19%to 45.35%,and the alkali metal content,ash content,and specific surface area were significantly reduced.The optimal route for biochar pro-duction is hydrothermal carbonization-pyrolysis(P-HC),resulting in biochar with a higher calorific value,C=C structure,and increased graphitization degree.The apparent activation energy(E)of the sample ranges from 199.1 to 324.8 kJ/mol,with P-HC having an E of 277.8 kJ/mol,lower than that of raw biomass,primary biochar,and anthracite.This makes P-HC more suitable for blast furnace injection fuel.Additionally,the paper proposes a path for P-HC injection in blast furnaces and calculates potential environmental benefits.P-HC of-fers the highest potential for carbon emission reduction,capable of reducing emissions by 96.04 kg/t when replacing 40wt%coal injec-tion.

关键词： blast furnace injection biomass cross-upgrading hydrothermal carbonization pyrolysis physicochemical properties gasific-ation properties