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Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong Zhu Ruijie Liu Jiang Ma Lina Hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

Protophyllocladoxylon jingyuanense ***.,a Gymnospermous Wood of the Serpukhovian(Late Mississippian) from Gansu,Northwest China

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Acta Geologica Sinica(English Edition) 2010年第2期84卷 257-268页

作者： ZHANG Yi WANG Jun LIU Lujun LI Nan Paleontological Institute of Shenyang Normal University Shenyang 110034 China Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China shenzhen fair lake botanical garden Shenzhen 518004 China

A new species of gymnospermous fossil wood, Protophyllocladoxylon jingyuanense sp. nov., is described from the lower part of the Tsingyuan Formation （Serpukhovian/Late Mississippian）, near the coal mine of Ciyao, Gansu, northwestern China. The specimen is preserved only in silicified secondary xylem, while growth rings are absent. Pits in radial tracheidal walls are araucaroid in type, uniseriate, occasionally biseriate. Xylem rays are homogeneous, uniseriate, occasionally biseriate. Cross-field pits are simple, large, one to two in number. Axial parenchyma is absent. The anatomical characters and geographic distribution of Protophyllocladoxylon woods through geological ages are documented. Those species with axial parenchyma and without growth rings live in warm climate, whereas the species without axial parenchyma and with growth rings are present either in warm or cool climate. The ideal living climate for Protophyllocladoxylon woods is warm and wet. Our new species, as a fossil wood of Early Carboniferous, is likely the earliest known species of Protophyllocladoxylon.

关键词： Protophyllocladoxylonjingyuanense growth rings axial parenchyma climate,

Axial nature of the cupule-bearing organ in Caytoniales

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Journal of Systematics and Evolution 2010年第3期48卷 207-214页

作者： 1,2Xin WANG 1(Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,China) 2(fairy lake botanical garden,shenzhen 518004,China) (Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China) (fairy lake botanical garden Shenzhen 518004 China)

Caytoniales are an important group of seed plants,and the nature of their female reproductive organ may influence interpretations of the seed plant phylogeny and the origin of *** not convincingly demonstrated by clear evidence,cupules on previously described specimens were interpreted as being distichously arranged,implying that the cupule-bearing organ in Caytoniales was a pinnate *** a female reproductive organ of Paracaytonia hongtaoi *** ***.(Caytoniales)is reported from Liaoning,*** well preserved specimen clearly shows a spiral arrangement of cupules along the reproductive axis,suggesting that the cupule-bearing organ in Caytoniales is not a megasporophyll but a *** new information on the axial nature of the cupule-bearing organ in Caytoniales has significant implications on the placement of Caytoniales in the seed plant phylogeny and interpretation of the relationship between Caytoniales and angiosperms.

关键词： angiosperms Caytoniales cupule evolution Paracaytonia seed plants systematics Yixian Formation.

Generation and characterization of expressed sequence tags(ESTs) from coralloid root cDNA library of Cycas debaoensis

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Plant Diversity 2018年第5期40卷 245-252页

作者： Yunhua Wang Nan Li Ting Chen Yiqing Gong shenzhen Key Laboratory of Southern Subtropical Plant Diversity Fairylake Botanical GardenShenzhen & Chinese Academy of Sciences

A normalized full-length cDNA library was constructed from the coralloid roots of Cycas debaoensis by the DSN （duplex-specific nuclease） normalization method combined with the SMART （Switching Mechanism At 5＇ end of the RNA Transcript） technique. The titer of the original cDNA library was about 1.5 × 10^6 cfu·mL^-1 and the average insertion size was about 1 kb with a high recombination rate （97%）. The 5011 high-quality expressed sequence tags （ESTs） were obtained from 5393 randomly picked cDNA clones. Clustering and assembly of ESTs resulted in 2984 unique sequences, consisting of 618 contigs and 2366 singlets. EST sequence annotation revealed that 2333 and 1901 unigenes were functionally anno- tated in the NCBI non-redundant database and Swiss-Prot protein database, respectively. Functional analysis demonstrated that 1495 （50.1%） unigenes were associated with 4082 Gene Ontology （GO） terms. A total of 847 unigenes were grouped into 22 Cluster of Orthologous Groups （COG） functional categories. Based on the EST dataset, 22 ESTs that encoded putative receptor-like protein kinase （RLK） genes were screened. Furthermore, a total of 94 simple sequence repeats （SSRs） were discovered, of which 20 loci were successfully amplified in C debaoensis. This study is the first EST analysis for the coralloid roots of C debaoensis and provides a valuable genomic resource for novel gene discovery, gene expression and comparative genomics, conservation and management studies as well as applications in C debaoensis and related cycad species.

关键词： Cycas debaoensis Coralloid root cDNA library Expressed sequence tags Symbiosis and defense SSRs

Schmeissneria:An angiosperm from the Early Jurassic

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Journal of Systematics and Evolution 2010年第5期48卷 326-335页

作者： 1,2Xin WANG 1(Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,China) 2(fairylake botanical garden,shenzhen 518004,China) (Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China) (fairylake botanical garden Shenzhen 518004 China)

The origin of angiosperms has been a focus of intensive research for a long *** so-called pre-Cretaceous angiosperms,including Schmeissneria,are usually clouded with *** expel the cloud around the enigmatic Schmeissneria,the syntype and new materials of Schmeissneria collected previously in Germany and recently in China are *** materials include female inflorescences and *** latter are old materials but were under-studied *** microscopy and scanning electron microscope observations indicate that the fruits in these infructescences have in situ seeds enclosed,and that the ovaries are closed be fore *** the plants meet two strict criteria for angiosperms:angiospermy plus *** Schmeissneria in angiosperms will extend the record of angiosperms up to the Early Jurassic,more compatible with many molecular dating conclusions on the age of angiosperms,and demanding a reassessment of the current doctrines on the origin of *** the phylogenetic relationship of Schmeissneria to other angiosperms apparently is still an open question,this study adds to research concerning the origin of angiosperms.

关键词： angiosperm earliest evolution flower fossil Germany Jurassic origin.

Whole fossil plants of Ephedra and their implications on the morphology,ecology and evolution of Ephedraceae (Gnetales)

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Chinese Science Bulletin 2010年第15期55卷 1511-1519页

作者： WANG Xin 1,2 & ZHENG ShaoLin 3 1 Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,China 2 fairy lake botanical garden,shenzhen 518004,China 3 Shenyang Institute of Geology and Mineral Resources,Shenyang 110034,China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China fairy lake botanical garden Shenzhen China Shenyang Institute of Geology and Mineral Resources Shenyang China

Although there are many reports of fossil Ephedraceae,whole plant fossil record remains *** to a lack of trust on partially preserved fossil materials,scholars working on molecular clock proposed a recent origin of Ephedra and cast doubt on the earlier origin time of *** better the understanding on this interesting group,here we report whole plants of Ephedra hongtaoi ***.(Ephedraceae,Gnetales) from the Yixian Formation (Early Cretaceous) in western Liaoning,*** whole plants of Ephedra demonstrate clearly the characters of Ephedra,including shrubby growth habit,decussate branching pattern,and terminal ovuliferous unit with micropylar *** whole-plant preservation of the fossils provides more convincing fossil evidence of Early Cretaceous Ephedra,helps to resolve the controversy over the origin time of Ephedra,and sheds light on the whole plant morphology,growth habit,ecology and evolution of Ephedraceae.

关键词：化石植物生态学麻黄形态学进化材料保存早白垩世生长习性

Mitochondrial RNA editing sites affect the phylogenetic reconstruction of gymnosperms

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Plant Diversity 2023年第4期45卷 485-489页

作者： Shan-Shan Dong Xu-Ping Zhou Tao Peng Yang Liu Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical GardenShenzhen&Chinese Academy of SciencesShenzhen 518004GuangdongChina School of Life Sciences Guizhou Normal UniversityGuiyang 550001GuizhouChina State Key Laboratory of Agricultural Genomics BGI-ShenzhenShenzhen 518083GuangdongChina

RNA editing is a post-transcriptional process that alters the genetic information of mRNAs,so that the translated proteins deviate from those predicted by the genomic DNA *** editing occurs in a wide range of eukaryotes,including protists,multicellular animals,and land plants(Gray,2012;Ichinose and Sugita,2016).RNA editing in animals,dominated by A-to-I synonymous editing with low editing efficiency(20e30%),might play important roles in the regulation of gene expression(Wang et al.,2013).In contrast,RNA editing in plant organelles is usually nonsynonymous,affecting mostly the 2nd and 1st codon positions with very high editing efficiency(~80%).In plants,RNA editing is thought to affect plant phenotype and growth by restoring evolutionarily conserved amino acids and ensuring the correct folding of trans-membrane proteins on the respiratory chain complex(Sloan,2017).

关键词： editing template

The genome of Magnolia biondii Pamp. provides insights into the evolution of Magnoliales and biosynthesis of terpenoids

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Horticulture Research 2021年第1期8卷 552-564页

作者： Shanshan Dong Min Liu Yang Liu Fei Chen Ting Yang Lu Chen Xingtan Zhang Xing Guo Dongming Fang Linzhou Li Tian Deng Zhangxiu Yao Xiaoan Lang Yiqing Gong Ernest Wu Yaling Wang Yamei Shen Xun Gong Huan Liu Shouzhou Zhang Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical GardenShenzhen&Chinese Academy of SciencesShenzhen 518004China State Key Laboratory of Agricultural Genomics BGI-ShenzhenShenzhen 518083China Nanjing Forestry University Nanjing 210037China Fujian Agriculture and Forestry University Fuzhou 350000China University of British Columbia Vancouver BCCanada Xi’an botanical garden Xi’an 710061China Zhejiang Agriculture and Forestry University Hangzhou 311300China Kunming botanical garden Chinese Academy of SciencesKunming 650201China Department of Biology University of CopenhagenDK-2100 CopenhagenDenmark

Magnolia biondii Pamp.(Magnoliaceae,magnoliids)is a phylogenetically,economically,and medicinally important ornamental tree species widely grown and cultivated in the north-temperate regions of *** the genome sequence of *** would help resolve the phylogenetic uncertainty of magnoliids and improve the understanding of individual trait evolution within the Magnolia *** assembled a chromosome-level reference genome of *** using~67,~175,and~154Gb of raw DNA sequences generated via Pacific Biosciences single-molecule real-time sequencing,10X Genomics Chromium,and Hi-C scaffolding strategies,*** final genome assembly was~2.22Gb,with a contig N50 value of 269.11 kb and a BUSCO complete gene percentage of 91.90%.Approximately 89.17%of the genome was organized into 19 chromosomes,resulting in a scaffold N50 of *** genome contained 47,547 protein-coding genes,accounting for 23.47%of the genome length,whereas 66.48%of the genome length consisted of repetitive *** confirmed a WGD event that occurred very close to the time of the split between the Magnoliales and *** enrichment of the Magnolia-specific and expanded gene families highlighted genes involved in the biosynthesis of secondary metabolites,plant–pathogen interactions,and responses to stimuli,which may improve the ecological fitness and biological adaptability of the *** analyses revealed a sister relationship of magnoliids and Chloranthaceae,which are sister to a clade comprising monocots and *** genome sequence of *** could lead to trait improvement,germplasm conservation,and evolutionary studies on the rapid radiation of early angiosperms.

关键词： evolution sister resolve

The discovery of whole-plant fossil cycad from the Upper Triassic in western Liaoning and its significance

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Chinese Science Bulletin 2009年第17期54卷 3116-3119页

作者： WANG Xin LI Nan WANG YongDong ZHENG ShaoLin Nanjing Institute of Geology and Palaeontology Nanjing 210008 China shenzhen fairylake botanical garden Shenzhen 518004 China Shenyang Center of China Geological Survey Shenyang 110034 China

A recently discovered megafossil of whole plant cycad is briefly reported here. The specimen is collected from the Yangcaogou Formation (Upper Triassic) in Changheying, Beipiao, Liaoning. The whole plant is preserved intact on a sandstone slab, 89 cm long and 130 cm wide, including leaves up to 82 cm long and a male cone physically attached to the stem apex. Analysis on the morphology, arrangement and venation of leaf and pinna, male cone and its relationship with other parts indicates that the fossil is closely related to living Zamiaceae in Cycadales. This cycad fossil is hitherto most completely preserved cycad specimen including both vegetative and reproductive organs. Its discovery contributes much to our understanding of the morphology and evolution of cycads, palaeoclimate as well as palaeoenvironment.

关键词：植物化石上三叠统苏铁目辽西苏铁属植物生殖器官营养生长植物演化