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Challenges of identifying putative planetary-origin meteorites of non-igneous material

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Geoscience Frontiers 2019年第5期10卷 1879-1890页

作者： Yana Anfinogenova john Anfinogenov National Research Tomsk Polytechnic University 30 Lenin Ave.Tomsk 634050Russia Tunguska Nature Reserve Ministry of Natural Resources and Environment of the Russian Federation8 Moskovskaya Str.VanavaraEvenki DistrictKrasnoyarsk Krai648490Russia

This paper summarizes the challenges of identifying planetary-origin meteorites of non-igneous composition - particularly those of sedimentary *** for putative sedimentary-origin (sedtype) meteorites and their potential parent bodies is reviewed,suggesting that the list of candidate parent bodies for sed-type meteorites includes,but is not limited to,Mars,Enceladus,Ganymede,Europa,Ceres,Vesta,and other hypothetical planets that existed between the orbits of Mars and Jupiter in the *** extraterrestrial origin and probable parent body for sed-type meteorites should be assessed based on multiple lines of evidence,and not solely limited to tests of oxygen and noble gas isotopes,whose signatures may undergo terrestrial contamination and which may exhibit significant heterogeneity within both the Solar System and parent cosmic *** observed fall of a cosmic body,evidence of hypervelocity fall,signs of impact,presence of fusion crust,melting,and/or shock deformation features in impactor fragments should be considered as priority signs of meteoritic origin.

关键词： 1908 Tunguska event Sed-type meteorite Mars Enceladus Icy moon Parent body of meteorite

Overview of legal traceability of GPS positioning in Australia

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Satellite Navigation 2020年第1期1卷 275-286页

作者： Guorong Hu john Dawson National Positioning Infrastructure Branch Geoscience AustraliaCnr Jerrabomberra Avenue and Hindmarsh Drive SymonstonGPO Box 378CanberraACT 2601Australia

Global Positioning System(GPS)position verification and legal traceability in Australia supports industry,trade,science and innovation and is trusted and recognized domestically and *** the end of 2017,the Australia’s national datum was transitioned from the Geocentric Datum of Australia 1994(GDA94)to the Geocentric Datum of Australia 2020(GDA2020).As such,the datum for the legal traceability of GPS positions in Australia has also moved to *** paper highlights the importance of legal metrology and measurement in terms of GPS positions in accordance with the National Measurement Act 1960(Commonwealth of Australia).Here we provide an overview of the process of issuing the so-called‘Regulation 13 Certificates’for Continuously Operating Reference Stations(CORS)across *** position verification methodology is detailed,including the quality control,metadata assurance,and dynamic management of the certificates as well as positional uncertainty determination of CORS with varying quality.A quality monitoring system of positions is also discussed along with how measurement traceability is ensured including short-term and long-term position monitoring schemes.

关键词： GPS Regulation 13 certificate Legal traceability GDA2020 Position verification

Looking back at the first twenty years of genomics

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Quantitative Biology 2022年第1期10卷 6-16页

作者： john Quackenbush Department of Biostatistics Harvard T.H.Chan School of Public HealthBostonMA 02115USA Channing Division of Network Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolBostonMA 02215USA Department of Data Science Dana-Farber Cancer InstituteBostonMA 02115USA

Earlier this year,we celebrated the twentieth anniversary of the publication of the first draft human genome sequence-or more correctly,the nearly simultaneous publication of draft versions of the public human genome ... 详细信息

关键词： draft anniversary celebrated

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妊娠子痫及高血压

中国循证医学杂志 2004年第10期4卷 716-722,729页

作者： Lelia duley 柯■初 Institute of Health Science University of Oxford

截至 2 0 0 2年 8月 ,有关妊娠子痫及高血压的临床证据如下 :预防 :①抗血小板药物 :1个系统评价发现 ,对可能发生先兆子痫的孕妇使用抗血小板药物 (主要是阿司匹林 )与使用安慰剂或不治疗相比 ,在降低发生先兆子痫的危险、减少胎儿死... 详细信息

截至 2 0 0 2年 8月 ,有关妊娠子痫及高血压的临床证据如下 :预防 :①抗血小板药物 :1个系统评价发现 ,对可能发生先兆子痫的孕妇使用抗血小板药物 (主要是阿司匹林 )与使用安慰剂或不治疗相比 ,在降低发生先兆子痫的危险、减少胎儿死亡和早产方面有统计学意义 ,在其他重要结局上无统计学意义。随后的 1个小样本随机对照试验 (RCT)也得出相似的结论。该系统评价还发现 ,无证据表明使用阿司匹林会比安慰剂增加孕妇或胎儿出血的危险。②补钙 (用于高危孕妇或钙摄入不足的孕妇 ) :1个系统评价发现 ,给孕妇补钙 ( 2g/d)与使用安慰剂相比 ,在降低先兆子痫的发病危险及减少胎儿出生时体重不足 2 5 0 0g方面有统计学意义 ,但对降低死产、住院期间围产儿死亡、减少剖腹产或早产没有统计学意义。③补镁 :1个系统评价发现 ,尚无充足证据证明补镁对有发生先兆子痫或其并发症危险的孕妇有效。④其它药物干预 :两个RCT比较了使用阿替洛伟或硝酸甘油与安慰剂 ,但由于纳入的病例数太少不能得出可靠结论。⑤限制盐的摄入 :1个系统评价的有限证据表明 ,低盐饮食与正常饮食相比 ,在降低孕妇先兆子痫的发生率方面无统计学差异。⑥VitC和VitE :在高危孕妇中进行的 1个RCT中 ,有限的证据显示 ,使用VitC和VitE与安慰剂相比。

关键词：妊娠子痫高血压临床证据疗效评价先兆子痫子痫

Florigen:One Found,More to Follow?

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Journal of Integrative Plant Biology 2006年第6期48卷 617-621页

作者： john Klejnot Department of Molecular Cell and Developmental Biology University of CaliforniaLos AngelesCA 90095-1606USA

Florlgen（s） are molecules that are synthesized In response to appropriate photoperlods and transmitted from leaves to shoot apices to promote floral Initiation. It has been recently discovered In Arabldopsls that mRNA of the FT gene acts as a florlgen. In Arabldopsls, cryptochromes and phytochromes mediate long- day promotion of CO protein expression, which activates FT mRNA expression In leaves. FT mRNA Is transmitted to the shoot apex, where it acts together with FD to activate transcription of floral meristem Identlty genes, resulting In floral initiation. The discovery of the molecular nature of a florlgen was a major scientific breakthrough In 2005.

关键词： florigen photoperiod flowering Arabidopsis light.

Qingdao 2010:Facilitating the dissemination of new discoveries in Crustacean Research

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Integrative Zoology 2011年第1期6卷 1-2页

作者： john Buckeridge Earth and Oceanic Systems Research Group RMIT University Melbourne Vic.3001 Australia

Over the period 20-25 June,2010,I had the good fortune to attend the Seventh International Crustacean Congress in Qingdao,*** specific conferences are very special events-giving us the opportunity to both share knowledge and to learn from colleagues who are interested in the narrower field(s)in which we are ***,with recent advances in molecular biology and microscopy,carcinology,which comprises crustacean biology,palaeontology,distribution and evolution,is now so diverse that sub-disciplines within it are becoming increasingly ***,this is so much so that except in meetings such as this congress,many of us lack real opportunities to discuss and debate other perspectives of our *** meeting at Qingdao provided such a venue,and it was particularly enjoyable.

关键词： Crustacea Qingdao narrow

On Finite Groups that are the Product of Two Subnormal Supersoluble Subgroups

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Acta Mathematica Sinica,English Series 2023年第1期39卷 30-36页

作者： john COSSEY Yang Ming LI Mathematics Department School of Mathematical ScienceThe Australian National UniversityCanberra2601Australia Department of Mathematics Guangdong University of EducationGuangzhou510310P.R.China

Denote the class of finite groups that are the product of two normal supersoluble subgroups and the class of groups that are the product of two subnormal supersoluble subgroups by B_(1)and B_(2),*** this paper,a characterisation of groups in B_(1)or in B_(2)is *** applying this new characterisation,some new properties of B_(1)(B_(2))and new proofs of many known results about B_(1)or B_(2)are ***,closure properties of B_(1)and B_(2)are discussed.

关键词： Finite group supersoluble group normal subgroup subnormal subgroup product of subgroups

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Seed biology

Journal of Integrative Plant Biology 2019年第5期61卷 530-532页

作者： john Harada Department of Plant Biology University of California

Seed biology is an intensive area of study,a reflection of the significance of seeds for several scientific *** an evolutionary perspective,the ability of plants to make seeds has conf erred major selective advantages,accounting,in part,for the success of seed plants as the largest and most species-rich group of land *** seed habit facilitates fertilization in non-aqueous environments,provides a level of physical and biological protect!on for the female gametophyte and embryo,allows for the massive accumulation of storage proteins,lipids,and/or carbohydrates in the embryo and/or endosperm to serve as a nutrient reserve for the germinating seed and developing seedling,and permits the embryo to remain in a developmentally arrested and metabolically quiescent state until environ mental conditions permit germination to occur(Steeves 1983).

关键词： Seed biology the ability of plants permit germination

Effects of Electric Field on Electronic States in a GaAs/GaAlAs Quantum Dot with Different Confinements

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Chinese Physics Letters 2008年第8期25卷 3021-3024页

作者： A. john Peter Vemuri Lakshminarayana Govt. Arts College Melur-625 106 Madurai India Mohamed Sathak Engineering College Kilakarai-623 806 Rarnnad India

Binding energies of shallow hydrogenic impurity in a GaAs/GaAlAs quantum dot with spherical confinement, parabolic confinement and rectangular confinement are calculated as a function of dot radius in the influence of electric field. The binding energy is calculated following a variational procedure within the effective mass approximation along with the spatial depended dielectric function. A finite confining potential well with depth is determined by the discontinuity of the band gap in the quantum dot and the cladding. It is found that the contribution of spatially dependent screening effects are small for a donor impurity and it is concluded that the rectangulax confinement is better than the parabolic and spherical confinements. These results are compared with the existing literature.

关键词： BINDING-ENERGY IMPURITY STATES HYDROGENIC IMPURITIES MAGNETIC-FIELDS DONOR STATES EXCITON GAAS-GA1-XALXAS CRYSTALLITES CLUSTERS GAAS