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GPS姿态确定的整数模糊度快速算法

控制工程（北京） 2000年第3期 58-65页

作者： E.Glenn Lightsey John L.Crassidis F.landis Markley 殷书平

本文介绍计算GPS姿态确定整数模糊解的一种新算法.该算法首先引用瞬时(静态)整数搜索法,利用一个几何不等式大大缩小搜索空间。然后利用批处理损失函数检验剩余的整数,以确定最优整数解。批处理损失函数将本体坐标系中表示的GPS矢线矢... 详细信息

本文介绍计算GPS姿态确定整数模糊解的一种新算法.该算法首先引用瞬时(静态)整数搜索法,利用一个几何不等式大大缩小搜索空间。然后利用批处理损失函数检验剩余的整数,以确定最优整数解。批处理损失函数将本体坐标系中表示的GPS矢线矢量表示为2个矢量之和;一个矢量与相位差测量有关,另一个与未知的整数倍波长有关。新算法有几个优点:不需要航天器的先验估计姿态信息;利用协方差阵表达式可检验算法本身的完整性;即使基线共面,也能判定整数模糊解。新算法的性能在一种动力学硬件仿真器上进行了检验。

关键词： GSP 全球定位系统姿态确定整数模糊度快速算法

Pleistocene glaciation advances the cryptic speciation of Stellera chamaejasme *** a major biodiversity hotspot

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Journal of Integrative Plant Biology 2024年第6期66卷 1192-1205页

作者： Santosh kumar Rana Hum kala Rana Jacob Blandis Tianhui kuang Juntong Chen Hengchang Wang Tao Deng Charles C.Davis Hang Sun CAS key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Arkansas Biosciences Institute Arkansas State UniversityJonesboroArkansas 72401USA School of Integrative Plant Science Section of Plant Biology and the L.H.Bailey HortoriumCornell UniversityIthacaNew York 14853USA BTI Computational Biology Center Boyce Thompson InstituteIthacaNew York 14853USA CAS key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Chinese Academy of SciencesWuhan Botanical GardenWuhan 430074China Department of Organismic and Evolutionary Biology HerbariaHarvard UniversityCambridgeMassachusetts 02138USA

The mountains of Southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate *** high species diversity in this mountain system has long been attributed to a complex set of factors,and recent large-scale macroevolutionary investigations have placed a broad timeline on plant diversification that stretches from 10 million years ago(Mya)to the *** our increasing understanding of the temporal mode of speciation,finer-scale populationlevel investigations are lacking to better refine these temporal trends and illuminate the abiotic and biotic influences of cryptic *** is largely due to the dearth of organismal sampling among closely related species and populations,spanning the incredible size and topological heterogeneity of this *** study dives into these evolutionary dynamics of speciation using genomic and ecomorphological data of Stellera chamaejasme *** identified four previously unrecognized cryptic species having indistinct morphological traits and large metapopulation of evolving lineages,suggesting a more recent diversification(~2.67-0.90 Mya),largely influenced by Pleistocene glaciation and biotic *** factors likely influenced allopatric speciation and advocated cyclical warming–cooling episodes along elevational gradients during the *** study refines the evolutionary timeline to be much younger than previously implicated and raises the concern that projected future warming may influence the alpine species diversity,necessitating increased conservation efforts.

关键词： cryptic speciation glacial-interglacial Hengduan Mountains north-south migration Stellera chamaejasme

An updated classification for the hyper-diverse genus Corydalis(Papaveraceae: Fumarioideae)based on phylogenomic and morphological evidence

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Journal of Integrative Plant Biology 2023年第9期65卷 2138-2156页

作者： Jun‐Tong Chen Magnus Lidén Xian‐Han Huang Liang Zhang Xin‐Jian Zhang Tian‐Hui kuang Jacob Blandis Dong Wang Tao Deng Hang Sun CAS key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Evolutionary Biology Centre Systematic BiologyUppsala UniversityUppsala 75236Sweden School of Integrative Plant Science Section of Plant Biology and the L.H.Bailey HortoriumCornell UniversityIthacaNew York 14853USA BTI Computational Biology Center Boyce Thompson InstituteIthacaNew York 14853USA School of Life Sciences Central China Normal UniversityWuhan 430079China

The genus Corydalis, with ca. 530 species, has long been considered taxonomically challenging because of its great variability. Previous molecular analyses,based on a few molecular markers and incomplete taxonomic sampling, were clearly inadequate to delimit sections and subgenera. We have performed phylogenetic analyses of Corydalis and related taxa,using 65 shared protein-coding plastid genes from313 accessions(including 280 samples of ca. 226species of Corydalis) and 152 universal low-copy nuclear genes from 296 accessions(including 271samples of Corydalis) covering all 42 previously recognized sections and five independent “series”.Phylogenetic trees were inferred using Bayesian Inference and Maximum Likelihood. Eight selected morphological characters were estimated using ancestral state reconstructions. Results include:(i) of the three subgenera of Corydalis, two are fully supported by both the plastid and nuclear data;the third,subg. Cremnocapnos, is weakly supported by plastid DNA only, whereas in the nuclear data the two included sections form successive outgroups to the rest of the genus;(ii) among all 42 sections and five“series”, 25 sections and one “series” are resolved as monophyletic in both data sets;(iii) the common ancestor of Corydalis is likely to be a perennial plant with a taproot, yellow flowers with a short saccate spur, linear fruits with recurved fruiting pedicels, and seeds with elaiosomes;(iv) we provide a new classification of Corydalis with four subgenera(of which subg. Bipapillatae is here newly described), 39 sections, 16 of which are consistent with the previous classification, 16 sections have been recircumscribed, one section has been reinstated and six new sections are established. Characters associated with lifespan, underground structures, floral spur, fruit and elaiosomes are important for the recognition of subgenera and sections. These new phylogenetic analyses combined with ancestral character reconstructions uncovered previo

关键词： character evolution Corydalis genome skimming Papaveraceae phylogeny

腰椎CT检查时脊柱外异常的发现率及临床意义

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国际医学放射学杂志 2012年第4期 376-377页

作者： S.Y. Lee M.S. landis I.G. Ross A. Goela A.E. Leung 唐光健 Department of Medical Imaging London Health Sciences Centre-University Hospital339 Windermere Rd London ON Canada N6A 5A5

摘要目的前瞻性确定门诊成年病人腰椎CT检查时脊柱外异常的出现率与临床意义。材料与方法此项前瞻性研究由机构审查委员会批准。因下腰痛和(或)神经根症状行腰椎CT检查的400例连续门诊成年病人(平均年龄49岁,男212例,女188例)均签署知... 详细信息

摘要目的前瞻性确定门诊成年病人腰椎CT检查时脊柱外异常的出现率与临床意义。材料与方法此项前瞻性研究由机构审查委员会批准。因下腰痛和(或)神经根症状行腰椎CT检查的400例连续门诊成年病人(平均年龄49岁,男212例,女188例)均签署知情同意书。

关键词：腰椎门诊脊柱成年病人临床意义 CT

Genomic convergence underlying high-altitude adaptation in alpine plants

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Journal of Integrative Plant Biology 2023年第7期65卷 1620-1635页

作者： Xu Zhang Tianhui kuang Wenlin Dong Zhihao Qian Huajie Zhang Jacob Blandis Tao Feng Lijuan Li Yanxia Sun Jinling Huang Tao Deng Hengchang Wang Hang Sun CAS key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture The Chinese Academy of SciencesWuhan Botanical GardenWuhan 430074China Center of Conservation Biology Core Botanical GardensThe Chinese Academy of SciencesWuhan 430074China Yunnan International Joint Laboratory for Biodiversity of Central Asia Key Laboratory for Plant Diversity and Biogeography of East AsiaKunming Institute of BotanyThe Chinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China School of Integrative Plant Science Section of Plant Biology and the L.H.Bailey HortoriumCornell UniversityIthacaNew York 14850USA BTI Computational Biology Center Boyce Thompson InstituteIthacaNew York 14853USA State key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 475004China Department of Biology East Carolina UniversityGreenvilleNorth Carolina 27858USA

Evolutionary convergence is one of the most striking examples of adaptation driven by natural ***, genomic evidence for convergent adaptation to extreme environments remains ***, we assembled reference genomes of two alpine plants, Saussurea obvallata(Asteraceae)and Rheum alexandrae(Polygonaceae), with 37,938 and 61,463 annotated protein-coding genes. By integrating an additional five alpine genomes,we elucidated genomic convergence underlying high-altitude adaptation in alpine plants. Our results detected convergent contractions of diseaseresistance genes in alpine genomes, which might be an energy-saving strategy for surviving in hostile environments with only a few pathogens *** identified signatures of positive selection on a set of genes involved in reproduction and respiration(e.g., MMD1, NBS1, and HPR), and revealed signatures of molecular convergence on genes involved in self-incompatibility, cell wall modification,DNA repair and stress resistance, which may underlie adaptation to extreme cold, high ultraviolet radiation and hypoxia environments. Incorporating transcriptomic data, we further demonstrated that genes associated with cuticular wax and flavonoid biosynthetic pathways exhibit higher expression levels in leafy bracts, shedding light on the genetic mechanisms of the adaptive “greenhouse” morphology. Our integrative data provide novel insights into convergent evolution at a high-taxonomic level,aiding in a deep understanding of genetic adaptation to complex environments.

关键词： adaptation alpine plants evolutionary rates genomic convergence “greenhouse”morphology high altitude

纳米压印光刻技术——下一代批量生产的光刻技术(英文)

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电子工业专用设备 2004年第7期33卷 3-9页

作者： R.Pelzer P.Lindner T.Glinsner B.Vratzov C.Gourgon S.landis P.kettner C.Schaefer EV Group DI Erich Thallner Strasse 1 A-4780 SchaerdingEV Group DI Erich Thallner Strasse 1 A-4780 SchaerdingEV Group DI Erich Thallner Strasse 1 A-4780 SchaerdingAMICA AMO GmbH Huysensweg 25 D-52074 AachenLaboratoire des Technologies de la Microelectronique-CNRS 17 R. des MartyrsF-38054 Grenoble CedexCEA-LETI17 R.des Martyrs F-38054 Grenoble CedexEV Group DI Erich Thallner Strasse 1 A-4780 SchaerdingEV Group DI Erich Thallner Strasse 1 A-4780 Schaerding

纳米压印光刻技术已被证实是纳米尺寸大面积结构复制的最有前途的下一代技术之一。这种速度快、成本低的方法成为生物化学、μ级流化学、μ-TAS和通信器件制造以及纳米尺寸范围内广泛应用的一种日渐重要的方法,如生物医学、纳米流体学... 详细信息

纳米压印光刻技术已被证实是纳米尺寸大面积结构复制的最有前途的下一代技术之一。这种速度快、成本低的方法成为生物化学、μ级流化学、μ-TAS和通信器件制造以及纳米尺寸范围内广泛应用的一种日渐重要的方法,如生物医学、纳米流体学、纳米光学应用、数据存储等领域。由于标准光刻系统的波长限制、巨大的开发工作量、以及高昂的工艺和设备成本,纳米压印光刻技术可能成为主流IC产业中一种真正富有竞争性方法。对细小到亚10nm范围内的极小复制结构,纳米压印技术没有物理极限。从几种纳米压印光刻技术中选择两种前景广阔的方法——热压印光刻(HEL)和紫外压印光刻(UV-NIL)技术给予介绍。两种技术对各种各样的材料以及全部作图的衬底大批量生产提供了快速印制。重点介绍了HEL和UV-NIL两种技术的结果。全片压印尺寸达200mm直径,图形分辨力高,拓展到纳米尺寸范围。

关键词：纳米压印技术热压印紫外压印电铸光刻