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Convergence analysis of projected gradient descent for Schatten-p nonconvex matrix recovery

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Science China Mathematics 2015年第4期58卷 845-858页

作者： CAI yun LI song Department of Mathematics Zhejiang University

The matrix rank minimization problem arises in many engineering applications. As this problem is NP-hard, a nonconvex relaxation of matrix rank minimization, called the Schatten-p quasi-norm minimization(0 < p < 1), has been developed to approximate the rank function closely. We study the performance of projected gradient descent algorithm for solving the Schatten-p quasi-norm minimization(0 < p < 1) *** on the matrix restricted isometry property(M-RIP), we give the convergence guarantee and error bound for this algorithm and show that the algorithm is robust to noise with an exponential convergence rate.

关键词： low rank matrix recovery nonconvex matrix recovery projected gradient descent restricted isometry property

Efficient and multifunctional terahertz polarization control device based on metamaterials

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Chinese Physics B 2020年第11期29卷 364-369页

作者： xiao-Fei Jiao Zi-Heng Zhang yun Xu Guo-Feng song Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Inorganic Stretchable and Flexible Information Technology Beijing 100083China

Terahertz polarization devices are an important part of terahertz optical *** terahertz polarization devices rely on birefringent crystals,and their performances are limited by the material *** this work,we theoretically demonstrate that the metamaterial consisting of the medium and the periodic metal band embedded in the medium can control broadband polarization *** transmission length of the subwavelength waveguide mode gives rise to a broadband transmission *** resonant cavity structure formed by the dielectric layer and the waveguide layer possesses a high transmission *** optimizing the metamaterial structure parameters,we design a high-efficient(>90%)quarter-wave plate over a frequency range of 0.90 THz-1.10 THz and a high-efficient(>90%)half-wave plate over a frequency range of 0.92 THz-1.02 ***,due to the anisotropy of the structure,the metamaterials with the same structural parameters can achieve the function of the polarized beam splitting with an efficiency of up to 99%over a frequency range of 0.10 THz-0.55 ***,the designed metamaterial has a multifunctional polarization control effect,which has potential applications in the terahertz integrated polarization optical system.

关键词： terahertz metamaterials waveguide transmission

在他乡良缘更好吗——迁移流动对个人婚姻匹配的影响

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山西财经大学学报 2025年第1期47卷 48-59页

作者：黄小丽丁金宏王俊松华东师范大学社会发展学院华东师范大学地理科学学院

基于2010—2021年中国综合调查数据，实证研究迁移流动对婚姻匹配的影响。结果表明：婚前迁移显著提升了匹配到配偶的社会经济地位，其中自身社会经济地位提高和择偶场域改善是实现配偶社会经济地位提升的重要解释机制；与婚后迁移者相... 详细信息

基于2010—2021年中国综合调查数据，实证研究迁移流动对婚姻匹配的影响。结果表明：婚前迁移显著提升了匹配到配偶的社会经济地位，其中自身社会经济地位提高和择偶场域改善是实现配偶社会经济地位提升的重要解释机制；与婚后迁移者相比，婚前迁移通过拓展迁移者的社会交往，使其有机会结识社会经济地位更高的异性。异质性分析表明：相较于农业户籍，婚前迁移对非农户籍人群配偶质量的提升效应更显著；与未迁移人群相比，这种提升效应在中下阶层更明显。结论意味着，迁移流动有可能成为提升个体婚姻匹配质量的重要途径。

关键词：迁移流动婚姻匹配社会经济地位社会交往同质匹配择偶场域婚前迁移婚后迁移

Sequencing and Analysis of Porcine Intrleukin-18 Gene

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Agricultural Science & Technology 2009年第1期10卷 89-92页

作者：曹素芳李明王岩刘长斗朱赞梅唐桂芬肖松云郑州牧业工程高等专科学校河南郑州450011 郑州先锋动物药业有限公司河南郑州450032 河南省大明动物药业有限公司河南郑州450027

[ Objective] To clone the porcine interleukin-18（/L-18） cDNA and explore the immunological effectiveness of porcine IL-18 as an adjuvant of genetic vaccine. [ Method] The spleen lymphccytes were isolated from Henan three-way cross-breeding pigs. According to the porcine IL-18 gene in GenBank, a pair of specific primers was designed. The full length cDNA of porcine IL-18 was amplified by RT-PCR. Subsequently, porcine IL-18 cDNA was cloned into pGEM-T vector and sequenced and analyzed. [ Result] The porcine IL-18 gene demonstrated an open reading frame of 579 bp encoding an inactive precursor protein with 192 amino acids. The precursor protein had no typical hydrophobic signal peptide and cleaved by interleukin-1 beta （IL-1β） converting enzyme（ICE） in caspase-1 splice site; the porcine mature protein had biological activity： After comparing with other porcine IL-18 genes, the nucleotide sequence homology was over 96% and the deduced amino acid homology was more than 98%. [ Conclusion] A full length procine IL-18 gene was gained. It lays the foundation for porcine IL-18 as an adjuvant of genetic vaccine.

关键词： Porcine Intedeukin-18 Sequencing Homology

Precise gradient separation of nanoparticles using reduced graphene oxide-polyoxomolybdate membranes

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Science China Chemistry 2025年第01期 209-216页

作者： Yixin Yang Wanlei Zhao Ruoxuan Zheng Hongqiang Li Wei Chen Yu-Fei song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Quzhou Institute for Innovation in Resource Chemical Engineering

The purification and size sieving of nanoparticles （NPs） represents a significant scientific ***,the r GO-polyoxometalates (POMs=PMo12,Mo132and Mo368) membranes were fabricated successfully via a simple and scalable POMsassisted in-situ photoreduction *** the mass ratio of r GO to PMo12was 1:30,the resultant r GO-PMo12membranes with highly ordered and uniform nanochannels of 1.0 nm can be obtained,which showed an accurate carbon quantum dots（CQDs） separation with a cut-off size approximately 1.0 *** increase of the size of the interlayered POMs from PMo12（1.0 nm）,{Mo132}（2.9 nm） to{Mo368}（3.8 nm）,the resultant r GO-PMo12,r GO-Mo132and r GO-Mo368exhibited precise gradient separation of CQDs and Au nanoparticles by size exclusion *** results pave a promising way to construct new twodimensional （2D） membranes for highly efficient size-selective separation.

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Construction and Identification of siRNA Expression Vector Targeting Nucleocapsid Protein N gene of PRRSV

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Agricultural Science & Technology 2009年第4期10卷 171-174页

作者：曹素芳李明王岩朱赞梅刘长斗唐桂芬肖松云郑州牧业工程高等专科学校河南郑州450011 河南大明药业有限公司河南郑州450027 郑州先锋动物药业有限公司河南郑州450032

[ Objective] The aim of this study was to investigate the construction and identification of siRNA expression vector targeting nucleocapsid protein N gone of PRRSV. [Method] Three siRNA oligonucleotides targeting nucleocapsid protein N gone sequence of PRRSV were designed or synthesized, and then inserted into CMV promoter downstream to clone into pSilencer 4,1 -CMV eukaryotic expression vector. The recombinant expression vector was identified by enzyme digestion and DNA sequencing. [ Result] The results showed that the siRNA interference recombinant plasmid vector pSilencer-N targeting nucleocapsid protein gone expression had been successfully constructed. [ Conclusion] This study lays a foundation for studies on the controlling PRRSV by RNA interference technique .

关键词： PRRSV Nucleocapsid protein N siRNA Expression vector

The future of global land change monitoring

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International Journal of Digital Earth 2023年第1期16卷 2279-2300页

作者： xiao-Peng song Department of Geographical Sciences University of MarylandCollege ParkMDUSA

Land change science co-evolves with remote sensing *** world has witnessed an exponential growth in Earth observation satellites since 1972,and concurrently,land change research has experienced transformative *** review summarizes the major milestones in global land cover and change mapping in a chronological order,from the pioneering efforts in the 1980s to the latest innovations at present,illustrating the tremendous progress in monitoring global land change from *** second part of the review presents a critical synopsis of the recent progress in land change research,focusing on the technical aspects of temporal trends characterization,change mapping and area estimation,as well as the applied aspects of driver attribution and the complex consequences to the Earth system and human *** last part of the article offers insights in the strategic directions of land change monitoring,including generation of analysis ready data,application of artificial intelligence algorithms,reconstruction of historical land change records,and near-real-time land change *** change science will continue to play a vital role in addressing a wide range of global challenges,including climate change and carbon sequestration,food security,sustainable energy transition,natural disaster relief and environmental change in conflicted societies.

关键词： Land cover land use remote sensing satellite global environmental change

A New Binary Carbazole Alkaloid from Murraya koenigii

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Chinese Chemical Letters 2002年第9期13卷 849-850页

作者： yun song WANG Hong Ping HE Xin HONG Qing ZHAO xiao Jiang HAO Laboratory of Phytochemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650204

A new binary carbazole alkaloid, 8, 8-biskoenigine (1), along with its monomer, koenigine, was isolated from the dried leaves of Murraya koenigii collected in Xishuangbanna, yunnan province. The structure of 1 was es... 详细信息

关键词： Murraya koenigii rusticate 8, 8-biskoenigine carbazole alkaloid.

Whole-exome sequencing identifies novel mutations in genes responsible for retinitis pigmentosa in 2 nonconsanguineous Chinese families

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International Journal of Ophthalmology(English edition) 2019年第6期12卷 915-923页

作者： Yan-Shan Hu Hui song Yin Li Zi-yun xiao Tuo Li Department of Ophthalmology the Central Hospital of Enshi Autonomous Prefecture Enshi Clinical College of Wuhan University

AIM: To detect the pathogenetic mutations responsible for nonsyndromic autosomal recessive retinitis pigmentosa(RP) in 2 nonconsanguineous Chinese families. METHODS: The clinical data, including detailed medical history, best corrected visual acuity(BCVA), slit-lamp biomicroscope examination, fundus photography, optical coherence tomography, static perimetry, and full field electroretinogram, were collected from the members of 2 nonconsanguineous Chinese families preliminarily diagnosed with RP. Genomic DNA was extracted from the probands and other available family members;wholeexome sequencing was conducted with the DNA samples provided by the probands, and all mutations detected by whole-exome sequencing were verified using Sanger sequencing in the probands and the other available family members. The verified novel mutations were further sequenced in 192 ethnicity matched healthy ***: The patients from the 2 families exhibited the typical symptoms of RP, including night blindness and progressive constriction of the visual field, and the fundus examinations showed attenuated retinal arterioles, peripheral bone spicule pigment deposits, and waxy optic discs. Whole-exome sequencing revealed a novel nonsense mutation in FAM161 A(c.943 A>T, ***315*) and compound heterozygous mutations in RP1 L1(c.56 C>A, ***19 His;c.5470 C>T, ***1824*). The nonsense c.5470 C>T, ***1824* mutation was novel. All mutations were verified by Sanger sequencing. The mutation ***315* in FAM161A co-segregated with the phenotype, and all the nonsense mutations were absent from the ethnicity matched healthy controls and all available ***: We identify 2 novel mutations in genes responsible for autosomal recessive RP, and the mutation in FAM161A is reported for the first time in a Chinese population. Our result not only enriches the knowledge of the mutation frequency and spectrum in the genes responsible for nonsyndromic RP but also provides a new target for

关键词： retinitis pigmentosa nonsyndromic whole-exome sequencing mutation novel