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Brief Introduction of Systematics of Tribe Phylini (Hemiptera: Miridae: Phylinae)
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作者 李晓明 刘国卿 《Plant Diseases and Pests》 CAS 2011年第5期28-31,共4页
Tribe Phylini belongs to the subfamily Phylinae and family Miridae with more species. Up to present, moer than 200 genera and about 2 000 species of Phylini have been known all around the world. They are mainly distri... Tribe Phylini belongs to the subfamily Phylinae and family Miridae with more species. Up to present, moer than 200 genera and about 2 000 species of Phylini have been known all around the world. They are mainly distributed in the Palaearetic, Nearctic, Oriental and Ethiopian region. This paper reviews the re- search history of Phylini, analyzes the establishment process of its classification system, and summarizes the research conditions of Phylini in China. 展开更多
关键词 MIRIDAE Phylini systematics China
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Species Concepts as Applied to the Whitefly Bemisia tabaci Systematics:How Many Species Are There? 被引量:79
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作者 LIU Shu-sheng John Colvin Paul J De Barro 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第2期176-186,共11页
The worldwide distribution and extensive genetic diversity of the whitefly,Bemisia tabaci,has long been recognized.However,the levels of separation within B.tabaci and the nomenclature of the various genetic groups ha... The worldwide distribution and extensive genetic diversity of the whitefly,Bemisia tabaci,has long been recognized.However,the levels of separation within B.tabaci and the nomenclature of the various genetic groups have been a subject of debate.Recent phylogenetic analyses indicate that B.tabaci is a complex composed of 28 morphologically indistinguishable species.In this article,we first review the debate and difficulties associated with B.tabaci's taxonomy and systematics,and argue for the need to apply the biological species concept in order to elucidate B.tabaci's systematics.We summarize the accumulated genetic and behavioural data on reproductive incompatibilities evident amongst phylogenetic mtCOI groups of B.tabaci.Crossing studies have been conducted with 14 of the 28 putative species covering 54 reciprocal inter-species pairs,and observations on mating behaviour have been conducted for seven species pairs.Data from both crossing trials and behavioural observations indicate a consistent pattern of reproductive isolation among the putative species.We then discuss the technical and conceptual complexities associated with crossing experiments and behavioural observations designed to reveal reproductive incompatibility.Finally,we elaborate on a strategy for further clarifying the pattern of reproductive isolation between B.tabaci groups and propose future research directions on the systematics of this complex. 展开更多
关键词 whitefly systematics biological species cryptic species phylogenetic species reproductive isolation mating behavior TAXONOMY
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He-Ar Isotopic Systematics of Fluid Inclusions in Pyrites from PGEpolymetallic Deposits in Lower Cambrian Black Rock Series, South China 被引量:16
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作者 SUNXiaoming WANGMin +2 位作者 XUETing MAMingyang LIYinhe 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期471-475,共5页
He-Ar isotopic compositions of fluid inclusions trapped in pyrites from some representative PGE-polymetallic deposits in Lower Cambrian black rock series in South China were analyzed by using an inert gas isotopic mas... He-Ar isotopic compositions of fluid inclusions trapped in pyrites from some representative PGE-polymetallic deposits in Lower Cambrian black rock series in South China were analyzed by using an inert gas isotopic mass spectrometer. The results show that the ore-forming fluids possess a low 3He/4He ratio, varying from 0.43×10-8 to 26.39×10-8, with corresponding R/Ra value of 0.003-0.189. The 40Ar/36Ar ratios are 258-287, close to those of air saturated water (ASW). He-Ar isotopic indicator studies show that the ore-forming fluids were mainly derived from the formation water or basinal hot brine and sea water, while the content of mantle-derived fluid or deep-derived magmatic water might be negligible. The PGE-polymetallic mineralization might be related to the evolution of the Caledonian miogeosynclines distributed along the southern margin of the Yangtze Craton. During the Early Cambrian, the formation water or basinal hot brine trapped in Caledonian basins which accumulated giant thick sediments was expelled and migrated laterally along strata because of the pressure generated by overlying sediments. The basinal hot brine ascended along faults, mixed with sea water and finally deposited ore minerals. 展开更多
关键词 He-Ar isotopic systematics pyrite fluid inclusions PGE-polymetallic deposit basinal hot brine
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Systematics,Behavior and Living Environment of Shantungosaurus Giganteus(Dinosauria:Hadrosauridae) 被引量:5
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作者 JI Yannan WANG Xuri +1 位作者 LIU Yongqing JI Qiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第1期58-65,共8页
On the basis of the taphonomy, osteological anatomy and ontogenetic variation, Zhuchengosaurus maximus Zhao et al., 2007 is considered to be synonymic with Shantungosaurus giganteus Hu, 1973 herein. This paper also de... On the basis of the taphonomy, osteological anatomy and ontogenetic variation, Zhuchengosaurus maximus Zhao et al., 2007 is considered to be synonymic with Shantungosaurus giganteus Hu, 1973 herein. This paper also deals with the life behavior of S. giganteus and the environment in which S. giganteus lived. S. giganteus is considered to be a terrestrial and gregarious herbivorous dinosaur and lived in hills and intervales in warm weather with plentiful rain and flourishing vegetation. 展开更多
关键词 Shantungosaurus giganteus life behavior systematics Late Cretaceous Zhucheng Shandong Province
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Selenium and Sulfur Systematics of Mafic Dykes in Western Fujian Province,Southern China 被引量:5
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作者 FAN Haifeng WEN Hanjie +1 位作者 ZHANG Guishan HU Ruizhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期884-895,共12页
Fifteen samples from three study areas (the Bancun diabase dykes, the Bali hornblende gabbro dykes, the Linzifen gabbro-diabase dykes) were collected and analyzed for selenium (Se), sulfur (S), copper (Cu), ma... Fifteen samples from three study areas (the Bancun diabase dykes, the Bali hornblende gabbro dykes, the Linzifen gabbro-diabase dykes) were collected and analyzed for selenium (Se), sulfur (S), copper (Cu), major and trace elements. In general, Se, S and Cu do positively correlate to each other. The concentration of S and Se and the S/Se ratio are higher than the corresponding value of primitive mantle (PM), and the Cu/S ratio falls in a narrow range (0.04-0.29), which is consistent with that of primitive mantle (0.05-0.20). The Bancun diabase dykes and the Bali hornblende gabbro dykes were located in an intraplate environment during the Late Mesozoic. Oceanic subduction was closely related to magmatic activities. The magmatic activities play an important role in the transportation mechanism of Se and S. Because those two groups were closer to fault zones, which may affect the distribution of S and Se and other elements. In the two groups, no crustal contamination was observed, indicating that all analyzed elements may come from enriched mantle metasomtism associated with slab subduction. However, the Linzifen gabbro-diabase dykes were located in an intraplate rift environment, and its invading age is older than the other two groups, the primitive magma comes from mantle, and there is an anomalous relation between S, Se and Al2O3, (La/Sm)N, and all these factors could result in higher S and Se concentration. 展开更多
关键词 selenium and sulfur systematics mafic dyke MESOZOIC Fujian southern China
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Systematics and Species Validity of the Dabieshan Pit Viper Protobothrops dabieshanensis Huang et al. 2012: Evidence from a Mitochondrial Gene Sequence Analysis 被引量:5
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作者 Baowei ZHANG Xin HUANG +4 位作者 Tao PAN Liang ZHANG Wenliang ZHOU Tao SONG Demin HAN 《Asian Herpetological Research》 SCIE 2013年第4期282-287,共6页
Aimed to evaluate the phylogenetic position of the recently described Protobothrops dabieshanensis Huang et al. (2012), phylogenic relationships of 12 species within Protobothrops based on four mtDNA gene fragments ... Aimed to evaluate the phylogenetic position of the recently described Protobothrops dabieshanensis Huang et al. (2012), phylogenic relationships of 12 species within Protobothrops based on four mtDNA gene fragments (12S RNA, 16S RNA, ND4 and Cyt b) were reconstructed in our study. The result indicates a clade composed ofP dabiesha- nensis, P. jerdonii and P xiangchengsis with strong support. The genetic distance among P dabieshanensis, P jerdonii and P xiangchengsis was much lower than other congeners. Based on the data from the phylogenetic analysis and pre- viously described morphological differences, we conclude that P dabieshanensis is a valid species with close affinities to P jerdonii and P xiangchengsis. 展开更多
关键词 phylogeny CROTALINAE systematics venomous snakes
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Factors Controlling Deposition of Metallic Minerals in the Meng’entaolegai Ag-Pb-Zn Deposit, Inner Mongolia, China: Evidence from Fluid Inclusions, Isotope Systematics, and Thermodynamic Model 被引量:2
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作者 He Yang Wanli Ma +2 位作者 Rui Wang Xueli Ma Keyong Wang 《Journal of Earth Science》 SCIE CAS CSCD 2020年第2期271-286,共16页
The Meng’entaolegai Ag-Pb-Zn vein-type deposit in Inner Mongolia,NE China is hosted in biotite/muscovite granite.This deposit includes the western(Zn-rich,deepest),middle(Zn-Pb rich)and eastern(Pb-Ag-rich,shallowest)... The Meng’entaolegai Ag-Pb-Zn vein-type deposit in Inner Mongolia,NE China is hosted in biotite/muscovite granite.This deposit includes the western(Zn-rich,deepest),middle(Zn-Pb rich)and eastern(Pb-Ag-rich,shallowest)ore-blocks.To better understand the metallogenic processes in ore district,we have undertaken a series of studies including fluid inclusion microthermometry,H-O-S-Pb isotope compositions and thermodynamic modeling.Based on fluid inclusion petrography,microthermometry results and HO isotope compositions,the ore-forming H2O-NaCl fluid inclusions are characterized by medium temperature and medium salinity.And two kinds of fluid processes(boiling in western and middle ore-block and fluid mixing in the eastern ore-block)were identified to explain the ore fluid evolution.More importantly,log ?O2-pH diagrams of δ^34S contours with the stability fields of Fe-and Cu-,Zn-,Pb-,and Ag-bearing minerals were constructed to restore the physicochemical conditions of ore-forming fluid in the western(270℃ and 80 bars),middle(250℃ and 70 bars),and eastern(230℃ and 50 bars)ore-blocks.As a result,the ore-forming conditions in the western and middle ore-block were similar.In the eastern ore-block,the fluids may have changed from acidic,S-poor and δ^34S(ΣS)≈2.8 to neutral,S-richer and δ^34S(ΣS)≈0.5,which imply that neutral S-rich meteoric water was mixed with the magmatic fluid.Meanwhile,the activity of Ag+was estimated to be about 10 ppm–9 ppm in the middle ore-block,but in the eastern ore-block it was about^10 ppm–12 ppm.We proposed that the key for Ag ore deposition was likely to be neutralization led by fluid mixing. 展开更多
关键词 fluid INCLUSIONS isotope systematics thermodynamic model Ag-Pb-Zn deposit Meng'entalegai NE China
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Isotope systematics and metallogenetic age of Zhuanghe gold deposit, Liaoning province, China 被引量:4
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作者 魏俊浩 谭文娟 +3 位作者 郭大招 谭俊 李闫华 鄢云飞 《Journal of Central South University of Technology》 EI 2007年第1期104-110,共7页
Based on the metallogenetic geology conditions, the H, O, C and S isotopic compositions were measured by MAT-251 mass spectrometer, and Pb isotope and Rb-Sr dating were carried with MAT-261 multi-acceptor mass spectro... Based on the metallogenetic geology conditions, the H, O, C and S isotopic compositions were measured by MAT-251 mass spectrometer, and Pb isotope and Rb-Sr dating were carried with MAT-261 multi-acceptor mass spectrometer. The results show that the δ^180 values of gold-bearing vein quartz from different levels are 1.19%-1.42%. The calculated δ^180 values of ore fluids are 0.55%-0.78%, and 319 values are from -8.64% to -6.66%. The calculated values of δ^34SH2s by the δ^34Spy values in quartz veins display sulfur isotope compositions from -0.053% to +0.413%. Carbon isotope compositions of carbonates are from -0.612% to 0.140%. The mole ratios of ^206Pb to ^204Pb, ^207Pb to ^204Pb and ^208Pb to ^204Pb in auriferous quartz vein are 16.987-17.545, 15.342-15.623, and 38.254-38.744, respectively. The age of the Zhuanghe gold deposit determined by Rb-Sr isochron of the fluid inclusions in quartzes is (143.0±5.8) Ma. These isotopic data suggest that the metallogenetic fluids are generated from magmatic hydrotherm and the origin of ore-forming matters is related to the deep-derived magmatic activities. Meanwhile, the metallogenetic epoch of the Zhuanghe gold deposit is in Yanshanian period. 展开更多
关键词 isotope systematics metallogenetic age Zhuanghe gold deposit
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On Evolutionary Sequence Systematics: Taking Permian Waagenophylloid Coral Fauna as an Example 被引量:2
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作者 Xu Guirong Gong Shuyun Wang Yongbiao(Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074) 《Journal of Earth Science》 SCIE CAS CSCD 1999年第3期215-227,共13页
Evolutionary sequence systematics is a discipline in paleontology and biology that deals with phylogeny of organism, the main purpose of which is to understand relatives between species and taxa and to show their evol... Evolutionary sequence systematics is a discipline in paleontology and biology that deals with phylogeny of organism, the main purpose of which is to understand relatives between species and taxa and to show their evolutionary sequence. The systematics is set up on the phenetic-cladistic systematics. A number of important theoretical concepts in the cladistics are added the concept of time in the systematics. For example, the time-span between the closest sister species is considered limited in the duration of their mother species. The foundational methodology of the systematics is to analyze sister-group and character mosaic distribution, and the key to study evolutionary sequence is to understand cbaracter mosaic distribution fully. These aualyses can be executed by using computer. In the paper, the Permian Waagenophylloid coral fauna is taken as an example to illustrate the analysis on evolutionary sequence. These coral fossils are widespread in Tethyan area.Seventeen characters and a number of cbaracter states for each character used in study result from features of Waagenophylloid corals. According to principles of tbe widest distribution of character states, fossil records and ontogenesis we discerned plesiomorph character states for each character. Characters are divided into 4 ranks on the basis of their important place in pkylogeny. Based on the theory and methopology of tbe evolutionary sequence systematics the paper analyzes the sister groups and evolutionary sequence. In the examination each other between the analyses of sister groups and evolutionary sequence tbe paper found many importunt phenomena of paleontology,such as character degeneration, parallel evolution, and polydirectional clades, and distinguished a number of abnormal order. Iu the discussion to test tke rirst occurrence event8 of biostratigraphy we infer the Possible stratigraphic levels of some fossils. 展开更多
关键词 evolutionary sequence systematics character mosaic distribution Permian Waagenophylloid corals
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Systematics, species diversity and new taxa of mesozooplankton in the West Pacific Ocean and its marginal seas: a brief compilation of monographs in China 被引量:1
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作者 WANG Yu HUANG Zongguo +9 位作者 WANG Chunguang HUANG Jiangshiou LIU Zhensheng XU Zhenzu HUANG Jiaqi CHEN Ruixiang LIAN Guangshan DAI Yanyu LIN Jinghong LIN Mao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第10期229-242,共14页
Research and protection of biodiversity is generally started with species recognizing guided by achievement of cataloguing and illustration obtained through in situ investigation data accumulation and literature learn... Research and protection of biodiversity is generally started with species recognizing guided by achievement of cataloguing and illustration obtained through in situ investigation data accumulation and literature learning. Facing the shortage of taxonomist, it is getting harder to maintain important specimen collections and handle loans. The West Pacific Ocean has been operating as a center of the origin of global marine biodiversity result of the richest species diversity of marine taxa found in these waters. The present work is a compilation and summary of systematics, species diversity and new taxa of mesozooplankton major group known in West Pacific Ocean and its marginal seas (0°-45°N, 105°-152°E) according to 6 203 mesozooplankton samples acquired from 701 stations during 1965 and 2008. A total of 2 657 species belonging to 686 genera and 206 families of 10 mesozooplankton groups have been found through taxonomic identification and document consulting. In details, 697 species from 251 genera of 99 families belong to the Medusozoa, 59 species from 22 genera of 12 families to the Ctenophora, 85 species from 36 genera of 14 families to the pelagic Mollusca (Pteropoda and Heteropoda), 416 species from 91 genera of 8 families to the Ostracoda, 908 species from 156 genera of 51 families to the Copepoda, 202 species from 60 genera of 4 families to the Mysidacea, 56 species from 8 genera of 2 families to the Euphausiacea, 105 species from 23 genera of 8 families to the Decapoda, 48 species from 13 genera of 5 families to the Chaetognatha and 81 species from 26 genera of 5 families to the Tunicata. The dominant species of each group are enumerated. Moreover, 2 new species of Medusozoa, Tubulariidae, Ectopleura, 1 new species of Medusozoa, Protiaridae, Halitiarella, 1 new genus and 1 new species of Medusozoa, Corymorphidae are established. An amount of 806 species are expanded with an increase of 43.5% on the basis of 1 852 species recorded before 2008, including 1.4% increase from tropical sea around equator, 4.0% from the frigid water in high latitude region, and 3.0% of bathypelagic-associated waters. The authors also summarized future prospects into five major areas in marine mesozooplankton research in China. Such information of qualitative phyletic classification could be of high relevance to studies on biodiversity and biogeography of marine mesozooplankton, especially for monographs contributed to make an overall and systematic conclusion on the species of marine life in China after 2008. 展开更多
关键词 marine mesozooplankton systematics species diversity new taxa COMPILATION the West Pacific Ocean marginal sea
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Diversifying on the Ark:multiple new endemic lineages of dwarf geckos from the Western Ghats provide insights into the systematics and biogeography of South Asian Cnemaspis(Reptilia:Squamata)
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作者 Saunak Pal Zeeshan A.Mirza +1 位作者 Princia Dsouza Kartik Shanker 《Zoological Research》 SCIE CAS CSCD 2021年第6期675-691,共17页
The highly speciose gekkonid genus Cnemaspis Strauch,1887 is polyphyletic,with three distantly related and geographically isolated clades from Africa,South Asia(SA),and Southeast Asia.At present,there are 85 known spe... The highly speciose gekkonid genus Cnemaspis Strauch,1887 is polyphyletic,with three distantly related and geographically isolated clades from Africa,South Asia(SA),and Southeast Asia.At present,there are 85 known species within SA Cnemaspis,although the number continues to increase rapidly with focused surveys and rigorous taxonomic work.Recent studies have provided valuable insights into the diversity and evolutionary history of SA Cnemaspis;however,most of these studies lack sufficient sampling in the Western Ghats(WG),where the genus has its greatest diversity.We addressed this research gap by conducting extensive sampling across the WG and re-examining museum specimens,thus providing a systematic account of various extant Cnemaspis species along with their distribution and natural history.We described 12 new species and a southern WG endemic clade of SA Cnemaspis.Ten of the newly described species are endemic to the forests of the southern WG.We also identified 10 well-supported subclades that can be separated across morphological,geographic,and phylogenetic axes.A time-calibrated phylogeny and ancestral area reconstructions confirmed the Paleocene origin of SA Cnemaspis in the WG and provide insights into its evolutionary history and biogeography.The discovery of multiple endemic and deeply divergent lineages further highlights the evolutionary significance of the WG for lizards. 展开更多
关键词 BIOGEOGRAPHY Cnemaspis Dwarf geckos Molecular phylogeny New species OSTEOLOGY South Asia systematics Western Ghats
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Predominance of linear Q and μ systematics in randominteraction ensembles
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作者 Zhen-Zhen Qin Yang Lei 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第11期247-253,共7页
In random-interaction ensembles, the electric quadrupole moments(Q) and magnetic moments(μ) of the Iπ = 11/2-isomers of the Cd isotopes predominantly exhibit a linear correlation with the neutron numbers,correspondi... In random-interaction ensembles, the electric quadrupole moments(Q) and magnetic moments(μ) of the Iπ = 11/2-isomers of the Cd isotopes predominantly exhibit a linear correlation with the neutron numbers,corresponding to the recently emphasized linear Q and μsystematics in realistic nuclear systems. Although the seniority scheme enhances such predominance(more essentially for μ), the configuration mixing due to quadrupole-like and δ-force-like proton-neutron(pn) interactions is responsible for the linear Q and μ systematics,respectively, in realistic nuclear system, as well as randominteraction ensembles. 展开更多
关键词 Random INTERACTION Electromagnetic MOMENT LINEAR systematics Proton–neutron INTERACTION
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Li and B Isotope Systematics of Ultrahigh-pressure Metamorphic Rocks from the Chinese Continental Scientific Drilling Program
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作者 Yilin Xiao Rolf L. Romer Jochen Hoefs Anette Meixner Zeming Zhang 《矿物岩石地球化学通报》 CAS CSCD 2007年第z1期81-82,共2页
  1 Introduction   Recent improvements in the precision of Li and B isotope measurements have demonstrated the potential of these elements in tracing a wide range of geological processes. The Li and B isotope sys...   1 Introduction   Recent improvements in the precision of Li and B isotope measurements have demonstrated the potential of these elements in tracing a wide range of geological processes. The Li and B isotope systematics of ultrahigh-pressure (UHP) metamorphic rocks provides a unique opportunity to investigate the behaviour of Li and B during fluid-rock interaction at high temperatures and very high pressures and to constrain the fluid budget and the recycling of subducted crustal materials into the mantle during UHP metamorphism.   …… 展开更多
关键词 ISOTOPE systematics ULTRAHIGH-PRESSURE METAMORPHIC CCSD
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Molecular systematics analysis of Lymantria dispar based on 18S rRNA and cox1 mtDNA sequence data
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作者 Xiao-Jun Fan Chang Zhang +2 位作者 Hui Ren Jian-Hong Liu Yan-Xia Mi 《Zoological Systematics》 CSCD 2015年第2期228-234,共7页
The complete sequence of the 18S ribosomal RNA gene (18S rRNA) from Lymantria dispar was cloned and analysed here. 18S rRNA and mitochondrial cytochrome c oxidasel (coxl) gene sequences of Lymantria dispar were co... The complete sequence of the 18S ribosomal RNA gene (18S rRNA) from Lymantria dispar was cloned and analysed here. 18S rRNA and mitochondrial cytochrome c oxidasel (coxl) gene sequences of Lymantria dispar were compared with homologous sequences of other nine insects from different orders. Analytic results showed that 18S rRNA of these insects had two conserved domains and the second domain was an even more conserved region. The phylogenetic trees based on the full-length sequence and the second domain fragment of 18S rRNA as well as sequence of coxl from different orders indicated that Lepidoptera and Trichoptera, which belongs to Amphiesmenoptera, had a closer phylogenetic relationship and fewer differences were observed comparing with traditional taxonomic results. 展开更多
关键词 LEPIDOPTERA Lymantria dispar 18S rRNA cox1 molecular systematics.
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Determination of r Factor of Kalbach-Mann Systematics for Energy Balance
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作者 ZHANG Jing-Shang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期947-950,共4页
Kalbach Mann systematics is a very useful formula to discrete the double-differential cross sections of emitted particles. However, the energy balance by using this systematics is still a task to be studied. In the fo... Kalbach Mann systematics is a very useful formula to discrete the double-differential cross sections of emitted particles. However, the energy balance by using this systematics is still a task to be studied. In the form of Legendre polynomial expansion the energy balance has been proved analytically. In terms of this approach, the formula to determine the prc-equilibrium fraction r factor of Kalbach Mann systematics has been obtained for keeping energy balance strictly. This formula could be straightforwardly applied for describing the double-differential cross sections of all projectile types in the eontinuum spectrum emissions. It indicates that Legendre expansion coefficient with l= 1 is the key term in the energy balance. 展开更多
关键词 energy balance pre-equilibrium emission systematics
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Problems in the Field of Systematics and Investigation of Conifers in Russia
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作者 Larisa Orlova Gennady Firsov 《Journal of Agricultural Science and Technology(B)》 2013年第12期880-886,共7页
The largest and most important family in Russian conifers is Pinaceae (27-29 species). The most important problems in the field of systemitics concern some critical taxa. In the result of author's research, the new... The largest and most important family in Russian conifers is Pinaceae (27-29 species). The most important problems in the field of systemitics concern some critical taxa. In the result of author's research, the new signs of vegetative and reproductive organs have been checked out and elaborated. It leads to the clarifying of new taxonomic status and geographical distribution of certain critical taxa. A set of species are threatened and need special measures which are included into the Red Data Book of Russian Federation. for their conservation. There are 13 species and one variety 展开更多
关键词 Conifers of Russia PINACEAE systematics ARBORICULTURE conservation.
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Pleistocene Radiolaria from Leg 119 Site 738B (Sections 1H1-1H2): Systematics and Biostratigraphy
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作者 Girish Kumar Sharma Sheetal Kanojia 《Open Journal of Geology》 2013年第8期427-438,共12页
This paper presents a record of radiolarian species from the sections (1H1-1H2) Leg 119 Site 738B of Southern Ocean region. Well diversified taxa of typical Antarctic assemblage are present in the sections. Thirty spe... This paper presents a record of radiolarian species from the sections (1H1-1H2) Leg 119 Site 738B of Southern Ocean region. Well diversified taxa of typical Antarctic assemblage are present in the sections. Thirty species were identified and illustrated from twenty-nine samples. On the basis of appearance, disappearance and abundance of taxa, viz. Omega and Psi zones are established and systematics of stratigraphically important species is described. These zones are equivalent to NR1 and NR2 of Upper Quaternary. 展开更多
关键词 PLEISTOCENE RADIOLARIA systematics BIOSTRATIGRAPHY Southern Indian Ocean
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