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Optimization of digital multi-beamforming for space-based ADS-B using distributed cooperative coevolution with an adaptive grouping strategy

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Chinese Journal of Aeronautics 2023年第10期36卷 391-408页

作者： Xueyuan LI Xuejun ZHANG Yuanhao TAN jianxiang ma School of Electronic Information Engineering Beihang UniversityBeijing 100191China Beijing Laboratory for General Aviation Technology Beihang UniversityBeijing 100191China Beijing Key management Laboratory for Network-based Cooperative Air Traffic management Beihang UniversityBeijing 100191China The Beihang University International Center for Innovation in Western China Chengdu 610218China

Space-based Automatic Dependent Surveillance-Broadcast(ADS-B)technology can eliminate the blind spots of terrestrial ADS-B systems because of its global coverage ***,the space-based ADS-B system faces new problems such as extremely low Signal-toNoise Ratio(SNR)and serious co-channel interference,which result in long update *** minimize the position message update interval at an update probability of 95%with full coverage constraint,this paper presents an optimization model of digital multi-beamforming for space-based ***,a coevolution method DECCG_A&A is proposed to enhance the optimization efficiency by using an improved adaptive grouping *** strategy is based on the locations of uncovered areas and the aircraft density under the coverage of each *** results show that the update interval can be effectively controlled to be below 8 seconds compared with other existing methods,and DECCG_A&A is superior in convergence to the Genetic Algorithm(GA)as well as the coevolution algorithms using other grouping ***,the proposed optimization model and method can significantly reduce the update interval,thus improving the surveillance performance of space-based ADS-B for air traffic control.

关键词： Adaptive grouping strategy Air traffic control Co-channel interference Coevolution algorithm Digital multi-beamforming Space-based Automatic Dependent SurveillanceBroadcast(ADS-B) Update interval

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Genome-scale angiosperm phylogenies based on nuclear,plastome,and mitochondrial datasets

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Journal of Integrative Plant Biology 2023年第6期65卷 1479-1489页

作者： Hongyin Hu Pengchuan Sun Yongzhi Yang jianxiang ma Jianquan Liu State Key Laboratory of Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000China Key Laboratory for Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065China

Angiosperms dominate the Earth’s ecosystems and provide most of the basic necessities for human *** major angiosperm clades comprise 64 orders,as recognized by the APGⅣ***,the phylogenetic relationships of angiosperms remain unclear,as phylogenetic trees with different topologies have been reconstructed depending on the sequence datasets utilized,from targeted genes to ***,we used currently available de novo genome data to reconstruct the phylogenies of 366 angiosperm species from 241 genera belonging to 97 families across 43 of the 64 orders based on orthologous genes from the nuclear,plastid,and mitochondrial genomes of the same species with compatible *** phylogenetic relationships were largely consistent with previously constructed phylogenies based on sequence variations in each genome ***,there were major inconsistencies in the phylogenetic relationships of the five Mesangiospermae lineages when different genomes were *** discuss ways to address these inconsistencies,which could ultimately lead to the reconstruction of a comprehensive angiosperm tree of *** angiosperm phylogenies presented here provide a basic framework for further updates and *** phylogenies can also be used as guides to examine the evolutionary trajectories among the three genome types during lineage radiation.

关键词： angiosperms divergence times genomic phylogenomics

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A point mutation resulting in a 13 bp deletion in the coding sequence of Cldf leads to a GA-deficient dwarf phenotype in watermelon

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Horticulture Research 2019年第1期6卷 121-132页

作者： Chunhua Wei Chunyu Zhu Liping Yang Wei Zhao Rongxue ma Hao Li Yong Zhang jianxiang ma Jianqiang Yang Xian Zhang State Key Laboratory of Crop Stress Biology in Arid Areas College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China

The dwarf architecture is an important and valuable agronomic trait in watermelon breeding and has the potential to increase fruit yield and reduce labor cost in crop ***,the molecular basis for dwarfism in watermelon remains largely *** this study,a recessive dwarf allele(designated as Cldf(Citrullus lanatus dwarfism))was fine mapped in a 32.88 kb region on chromosome 09 using F2 segregation populations derived from reciprocal crossing of a normal line M08 and a dwarf line *** annotation of the corresponding region revealed that the Cla015407 gene encoding a gibberellin 3β-hydroxylase functions as the best possible candidate gene for *** analysis showed that the fourth polymorphism site(a G to A point mutation)at the 3′AG splice receptor site of the intron leads to a 13 bp deletion in the coding sequence of Cldf in dwarf line N21 and thus results in a truncated protein lacking the conserved domain for binding *** addition,the dwarf phenotype of Cldf could be rescued by exogenous GA3 *** analysis suggested that the small multigene family GA3ox(GA3 oxidase)in cucurbit species may originate from three ancient lineages in *** these data support the conclusion that Cldf is a GA-deficient mutant,which together with the cosegregated marker can be used for breeding new dwarf cultivars.

关键词： dwarf breeding cultivar

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Methyl jasmonate mediates melatonin-induced cold tolerance of grafted watermelon plants

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Horticulture Research 2021年第1期8卷 830-841页

作者： Hao Li Yanliang Guo Zhixiang Lan Kai Xu Jingjing Chang Golam Jalal Ahammed jianxiang ma Chunhua Wei Xian Zhang State Key Laboratory of Crop Stress Biology for Arid Areas College of HorticultureNorthwest A&F University712100 YanglingShaanxiChina College of Horticulture and Plant Protection Henan University of Science and Technology471023 LuoyangHenanChina State Key Laboratory of Vegetable Germplasm Innovation 300384 TianjinChina

Root–shoot communication has a critical role in plant adaptation to environmental *** is widely applied to enhance the abiotic stress tolerance of many horticultural crop species;however,the signal transduction mechanism involved in this tolerance remains ***,we show that pumpkin-or figleaf gourd rootstock-enhanced cold tolerance of watermelon shoots is accompanied by increases in the accumulation of melatonin,methyl jasmonate(MeJA),and hydrogen peroxide(H_(2)O_(2)).Increased melatonin levels in leaves were associated with both increased melatonin in rootstocks and MeJA-induced melatonin biosynthesis in leaves of plants under cold *** melatonin increased the accumulation of MeJA and H_(2)O_(2) and enhanced cold tolerance,while inhibition of melatonin accumulation attenuated rootstock-induced MeJA and H_(2)O_(2) accumulation and cold *** application induced H_(2)O_(2) accumulation and cold tolerance,but inhibition of JA biosynthesis abolished rootstock-or melatonin-induced H_(2)O_(2) accumulation and cold ***,inhibition of H_(2)O_(2) production attenuated MeJA-induced tolerance to cold *** together,our results suggest that melatonin is involved in grafting-induced cold tolerance by inducing the accumulation of MeJA and H_(2)O_(2).MeJA subsequently increases melatonin accumulation,forming a self-amplifying feedback loop that leads to increased H_(2)O_(2) accumulation and cold *** study reveals a novel regulatory mechanism of rootstock-induced cold tolerance.

关键词： melatonin grafted mechanism

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Detection and Classification on Amateur Drones Based on Cepstrum of Radio Frequency Signal

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Transactions of Nanjing University of Aeronautics and Astronautics 2021年第4期38卷 597-606页

作者： GUAN Xiangmin ma jianxiang ZHANG Weidong Key Laboratory of General Aviation Operation Civil Aviation Management Institute of ChinaBeijing 100102P.R.China Zhejiang Key Laboratory of General Aviation Operation Technology General Aviation Institute of Zhejiang JiandeJiande 311612P.R.China Innovation Institute(Chengdu) Beihang UniversityChengdu 611930P.R.China School of Electronic and Information Engineering Beihang UniversityBeijing 100191P.R.China

As a prospective component of the future air transportation system,unmanned aerial vehicles(UAVs)have attracted enormous interest in both academia and ***,small UAVs are barely supervised in the current *** accidents or illegal airspace invading caused by these small drones affect public security *** solve this security problem,we use the back-propagation neural network(BPNN),the support-vector machine(SVM),and the k-nearest neighbors(KNN)method to detect and classify the non-cooperative drones at the edge of the flight restriction zone based on the cepstrum of the radio frequency(RF)signal of the drone’s *** signal from five various amateur drones and ambient wireless devices are sampled in an electromagnetic clean *** detection and classification algorithm based on the cepstrum properties is *** of the outdoor experiments suggest the proposed workflow and methods are sufficient to detect non-cooperative drones with an average accuracy of around 90%.The mainstream downlink protocols of amateur drones can be classified effectively as well.

关键词： drone detection radio frequency signal cepstrum machine learning

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The role of watermelon caffeic acid O-methyltransferase (ClCOMT1) in melatonin biosynthesis and abiotic stress tolerance

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Horticulture Research 2021年第1期8卷 2937-2948页

作者： Jingjing Chang Yanliang Guo Jingyi Yan Zixing Zhang Li Yuan Chunhua Wei Yong Zhang jianxiang ma Jianqiang Yang Xian Zhang Hao Li State Key Laboratory of Crop Stress Biology for Arid Areas College of HorticultureNorthwest A&F UniversityYanglingShaanxiChina State Key Laboratory of Vegetable Germplasm Innovation TianjinChina

Melatonin is a pleiotropic signaling molecule that regulates plant growth and responses to various abiotic *** last step of melatonin synthesis in plants can be catalyzed by caffeic acid O-methyltransferase(COMT),a multifunctional enzyme reported to have N-acetylserotonin O-methyltransferase(ASMT)activity;however,the ASMT activity of COMT has not yet been characterized in nonmodel plants such as watermelon(Citrullus lanatus).Here,a total of 16 putative O-methyltransferase(ClOMT)genes were identified in *** them,ClOMT03(Cla97C07G144540)was considered a potential COMT gene(renamed ClCOMT1)based on its high identities(60.00–74.93%)to known COMT genes involved in melatonin biosynthesis,expression in almost all tissues,and upregulation under abiotic *** ClCOMT1 protein was localized in the *** of ClCOMT1 significantly increased melatonin contents,while ClCOMT1 knockout using the CRISPR/Cas-9 system decreased melatonin contents in watermelon *** results suggest that ClCOMT1 plays an essential role in melatonin biosynthesis in *** addition,ClCOMT1 expression in watermelon was upregulated by cold,drought,and salt stress,accompanied by increases in melatonin *** of ClCOMT1 enhanced transgenic Arabidopsis tolerance against such abiotic stresses,indicating that ClCOMT1 is a positive regulator of plant tolerance to abiotic stresses.

关键词： methyltransferase COMT stress

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The Corylus mandshurica genome provides insights into the evolution of Betulaceae genomes and hazelnut breeding

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Horticulture Research 2021年第1期8卷 577-589页

作者： Ying Li Pengchuan Sun Zhiqiang Lu Jinyuan Chen Zhenyue Wang Xin Du Zeyu Zheng Ying Wu Hongyin Hu Jiao Yang jianxiang ma Jianquan Liu Yongzhi Yang State Key Laboratory of Grassland Agro-Ecosystem Institute of Innovation Ecology&School of Life SciencesLanzhou UniversityLanzhouChina Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education&State Key Laboratory of Hydraulics&Mountain River Engineering College of Life SciencesSichuan UniversityChengduChina CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences666303 MenglaYunnanChina Center of Plant Ecology Core Botanical GardensChinese Academy of Sciences666303 MenglaYunnanChina

Hazelnut is popular for its flavor,and it has also been suggested that hazelnut is beneficial to cardiovascular health because it is rich in oleic ***,we report the first high-quality chromosome-scale genome for the hazelnut species Corylus mandshurica(2n=22),which has a high concentration of oleic acid in its *** assembled genome is 367.67Mb in length,and the contig N50 is 14.85 *** contigs were assembled into 11 chromosomes,and 28,409 protein-coding genes were *** reconstructed the evolutionary trajectories of the genomes of Betulaceae species and revealed that the 11 chromosomes of the hazelnut genus were derived from the most ancestral karyotype in Betula pendula,which has 14 protochromosomes,by inferring homology among five Betulaceae *** identified 96 candidate genes involved in oleic acid biosynthesis,and 10 showed rapid evolution or positive *** findings will help us to understand the mechanisms of lipid synthesis and storage in *** gene families related to salicylic acid metabolism and stress responses experienced rapid expansion in this hazelnut species,which may have increased its stress *** reference genome presented here constitutes a valuable resource for molecular breeding and genetic improvement of the important agronomic properties of hazelnut.

关键词： breeding mandshurica evolution

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Disruption of the bHLH transcription factor Abnormal Tapetum 1 causes male sterility in watermelon

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Horticulture Research 2021年第1期8卷 3413-3424页

作者： Ruimin Zhang Jingjing Chang Jiayue Li Guangpu Lan Changqing Xuan Hao Li jianxiang ma Yong Zhang Jianqiang Yang Shujuan Tian Li Yuan Xian Zhang Chunhua Wei State Key Laboratory of Crop Stress Biology for Arid Areas College of HorticultureNorthwest A&F UniversityYangling 712100 ShaanxiChina State Key Laboratory of Vegetable Germplasm Innovation Tianjin Kernel Vegetable Research InstituteTianjin 300384China

Although male sterility has been identified as a useful trait for hybrid vigor utilization and hybrid seed production,its underlying molecular mechanisms in Cucurbitaceae species are still largely ***,a spontaneous male-sterile watermelon mutant,Se18,was reported to have abnormal tapetum development,which resulted in completely aborted pollen ***-based cloning demonstrated that the causal gene Citrullus lanatus Abnormal Tapetum 1(ClATM1)encodes a basic helix-loop-helix(bHLH)transcription factor with a 10-bp deletion and produces a truncated protein without the bHLH interaction and functional(BIF)domain in Se18 ***–PCR and RNA in situ hybridization showed that ClATM1 is specifically expressed in the tapetum layer and in microsporocytes during stages 6–8a of anther *** genetic function of ClATM1 in regulating anther development was verified by CRISPR/Cas9-mediated ***,ClATM1 was significantly downregulated in the Se18 mutant,displaying a clear dose effect at the transcriptional *** dual-luciferase reporter,β-glucuronidase(GUS)activity,and yeast one-hybrid assays indicated that ClATM1 could activate its own transcriptional expression through promoter ***,ClATM1 is the first male sterility gene cloned from watermelon,and its self-regulatory activity provides new insights into the molecular mechanism underlying anther development in plants.

关键词： bHLH sterility sterile

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