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基于Cerebrus的Genus+Innovus流程的功耗面积优化
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作者 汪锋刚 晋亚紧 +1 位作者 周国华 刘宇峥 《电子技术应用》 2024年第8期21-25,共5页
对于性能功耗面积(PPA)的追求已成为IC芯片设计的共识,尤其是发展到先进工艺节点,PPA已成为IC设计综合性能的重要指标,尤其是对于大型SoC芯片中clone很多次的模块,对于PPA的追求变得更加极致。介绍了基于Cadence公司的Genus工具和Cereb... 对于性能功耗面积(PPA)的追求已成为IC芯片设计的共识,尤其是发展到先进工艺节点,PPA已成为IC设计综合性能的重要指标,尤其是对于大型SoC芯片中clone很多次的模块,对于PPA的追求变得更加极致。介绍了基于Cadence公司的Genus工具和Cerebrus工具,通过综合阶段与后端PR各个阶段的优化,共同提升PPA的优化方案。最终结果显示,在时序及DRC基本收敛的情况下,使用Cerebrus工具相比Innovus可以使功耗降低3.5%,面积降低3.1%,使用Genus+Innovus流程可以使功耗降低6.4%,面积降低8.5%,极大地降低了芯片的面积及功耗。 展开更多
关键词 芯片设计 genus工具 Cerebrus工具 PPA优化
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Contribution to the Knowledge of the Afrotropical Spilomelinae (Lepidoptera, Crambidae): A New Genus in the Tribe Nomophilini Kuznetzov & Stekolnikov 1979 Based on Morphology and DNA Barcoding
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作者 Michael Seizmair 《Advances in Entomology》 2024年第3期155-169,共15页
The new genus Parathrausta gen.n. in the subfamily Spilomelinae (Lepidoptera, Crambidae) is erected based on a series of specimens collected in the Afrotropical region of Saudi Arabia. The new genus is monotypical, wi... The new genus Parathrausta gen.n. in the subfamily Spilomelinae (Lepidoptera, Crambidae) is erected based on a series of specimens collected in the Afrotropical region of Saudi Arabia. The new genus is monotypical, with Parathrausta internervalis sp.n. its type species. The adults of the type species, the male genitalia, the female genitalia and the tympanal organs are described and figured. The new genus is recognized as related by characters in the male and female genitalia with genera in the tribes Steniini Guine, 1854 and Nomophilini Kuznetzov & Stekolnikov, 1979, namely with Bradina Lederer, 1863, Perisyntrocha Meyrick, 1894, Diathrausta Lederer, 1863, Diasemiopsis Munroe, 1957, Diasemiodes Munroe, 1957 and with the genera in the Duponchelia Zeller, 1847 group comprising Duponchelia Zeller, 1847, Penestola Mschler, 1890, Tatobotys Butler, 1880 and Hymenoptychis Zeller, 1852. The character states differentiating the new genus from the comparative genera are discussed. Potential autapomorphies of the new genus are listed. The tribal assignment of the new genus to the Nomophilini Kuznetzov & Stekolnikov, 1979 based on morphological characters is discussed. The support of the tribal and cladistic assignment of the new genus as a sister clade to Diathrausta Lederer, 1863 based phylogenetic analyses (NJ, MP and ML) is shown. An unusually strong genetic divergence of the genus in the COI segment of the mt-DNA based on the Tamura-Nei distance measure from the morphologically related genera is recognized and addressed. 展开更多
关键词 PYRALOIDEA Taxonomy MORPHOLOGY COI New genus New Species Arabian Peninsula
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河南郑州、许昌两地区杆野螟属(Genus Ostrinia)的近缘种研究 被引量:9
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作者 姜仲雪 罗梅浩 +3 位作者 田娟 黄兆阁 吴剑英 李爱民 《河南农业大学学报》 CAS CSCD 1990年第3期293-300,共8页
1979年至1986年在许昌、郑州两地采集的卵、幼虫和成虫,经过生殖隔离、室内生物测定,最后将部分雌、雄蛾制成针插标本,部分雌、雄蛾的尾部制成雄外生殖器和雌蛾交配囊的装片和中足的装片,结果确定河南郑州和许昌两地区杆野螟属的近缘种... 1979年至1986年在许昌、郑州两地采集的卵、幼虫和成虫,经过生殖隔离、室内生物测定,最后将部分雌、雄蛾制成针插标本,部分雌、雄蛾的尾部制成雄外生殖器和雌蛾交配囊的装片和中足的装片,结果确定河南郑州和许昌两地区杆野螟属的近缘种有亚洲玉米螟(Ostrinia,farnacalis(Guen(?)e)、欧洲玉米螟(O.nubilalis(Hübner))、豆螟(O.scarulalis(Walker))、刺菜螟(O.zealis(Guenee))、苍耳螟(O.orienlalis Mutuura & Munroe)、杂草蛀螟(O.obumbralalis(Lederer))和O.dorsirittala(Moore)共7种,其中亚洲玉米螟为优势种,后3种国内尚未见报道。 展开更多
关键词 杆野螟属 近缘种 玉米螟 性诱剂
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Outcomes of mobile bearing unicompartmental knee arthroplasty in medial osteoarthritis knee with and without preoperative genu recurvatum 被引量:10
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作者 Boonchana Pongcharoen Krit Boontanapibul 《World Journal of Orthopedics》 2018年第9期149-155,共7页
AIM To compare clinical outcomes of patients with and without preoperative genu recurvatum(GR) following mobile bearing unicompartmental knee arthroplasty(UKA). METHODS We prospectively followed 176 patients for at le... AIM To compare clinical outcomes of patients with and without preoperative genu recurvatum(GR) following mobile bearing unicompartmental knee arthroplasty(UKA). METHODS We prospectively followed 176 patients for at least 24 mo who had been treated by unilateral, minimally invasive, Oxford UKA. Patients with medial osteoarthritis(OA) knee and preoperative GR(Group Ⅰ) accounted for 18%(n = 32) and patients without preoperative GR(Group Ⅱ) accounted for the remaining 82%(n = 144). Knee score, pain scores, and functional scores were assessed for each patient and compared between the two groups. The incidence of postoperative GRand the postoperative hyperextension angles also were recorded and analyzed. RESULTS The pain score, knee score and functional score were not significantly different between the two groups. Similarly, the incidence of postoperative GR and the measured hyperextension angles were not significantly different between the two groups. The incidence of postoperative GR was 1/32(3.12%) in Group Ⅰ and 1/144(0.69%) in Group Ⅱ(P = 0.34). The mean postoperative hyperextension angles were 2.40°± 2.19°(range: 1°-7°) for Group Ⅰ and 1.57°± 3.51°(range: 1°-6°) for Group Ⅱ(P = 0.65).CONCLUSION Medial OA of the knee and concomitant GR is not a contraindication for the mobile bearing UKA. 展开更多
关键词 UNICOMPARTMENTAL KNEE genu recurvatum Osteoarthritis HYPEREXTENSION KNEE KNEE ARTHROPLASTY Oxford KNEE
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中国血蜱属(蜱螨目:硬蜱科)研究:嗜鸟血蜱亚属Subgenus Ornithophysalis附一新记载种 被引量:2
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作者 孙毅 魏川川 +1 位作者 许荣满 刘晓 《寄生虫与医学昆虫学报》 CAS 2012年第1期50-56,共7页
中国的血蜱属嗜鸟血蜱亚属已知有3种,即嗜鸟血蜱 Haemaphysalis (Ornithophilis) ornithophila Hoogstraal et Kohls,板齿鼠血蜱 Hae.(Or.) bandicota Hoogstraal et Kohls,钝刺血蜱 Hae.(Or.) doenitzi Warburton et Nuttall,加... 中国的血蜱属嗜鸟血蜱亚属已知有3种,即嗜鸟血蜱 Haemaphysalis (Ornithophilis) ornithophila Hoogstraal et Kohls,板齿鼠血蜱 Hae.(Or.) bandicota Hoogstraal et Kohls,钝刺血蜱 Hae.(Or.) doenitzi Warburton et Nuttall,加上本文报道的中国新记载种,啄木鸟血蜱Hae.(Or.) megalaimae Rajagopalan,共4个种,并编制了分种检索表. 展开更多
关键词 血蜱属 嗜鸟血蜱亚属 检索表
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Review of the genus Brachytarsophrys(Anura:Megophryidae),with revalidation of Brachytarsophrys platyparietus and description of a new species from China 被引量:6
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作者 Yao Li Dan-Dan Zhang +8 位作者 Zhi-Tong Lyu Jian Wang Yu-Long Li Zu-Yao Liu Hong-Hui Chen Ding-Qi Rao Zhi-Fang Jin Chang-You Zhang Ying-Yong Wang 《Zoological Research》 SCIE CAS CSCD 2020年第2期105-122,共18页
The genus-level recognition of monophyletic short-legged toads(Brachytarsophrys)has been recently implicated in the taxonomic debate of Megophrys sensu lato.In the present study,Brachytarsophrys is reasonably regarded... The genus-level recognition of monophyletic short-legged toads(Brachytarsophrys)has been recently implicated in the taxonomic debate of Megophrys sensu lato.In the present study,Brachytarsophrys is reasonably regarded as a distinct genus based on significant morphological differentiations and recent molecular analyses.Furthermore,a comprehensive review of this genus is performed,with two species groups proposed based on morphological differences and phylogenetic relationships.Particularly,Brachytarsophrys platyparietus is removed as a synonym of Brachytarsophrys carinense and considered a valid species due to significant genetic divergence and distinct morphological differences.In addition,a new species,Brachytarsophrys orientalis sp.nov.,is described based on a series of specimens collected from southeastern China.This work takes the member species of the genus Brachytarsophrys to seven,suggesting that the diversity of Brachytarsophrys is underestimated.In addition,the genus levels of other monophyletic groups within the subfamily Megophryinae are discussed. 展开更多
关键词 genuS level Megophryinae Morphology PHYLOGENY Revision
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Species differentiation and identification in the genus of Helicobacter 被引量:5
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作者 HUA Jie Song, ZHENG Peng Yuan and HO Bow 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第1期12-14,共3页
Asearlyasnineteencentury,incidentalpresenceofspiralorganismswasnotedinthestomachsofdogs[1],ratsandcats[2].In... Asearlyasnineteencentury,incidentalpresenceofspiralorganismswasnotedinthestomachsofdogs[1],ratsandcats[2].Intheearlyyearsofth... 展开更多
关键词 HELICOBACTER genuS SPECIES biological features BIOCHEMICAL tests IDENTIFICATION DIFFERENTIATION
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New Genus and Species of Fossil Dragonflies (Insecta: Odonata) from the Yixian Formation of Northeastern China 被引量:4
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作者 ZHANG Binglan REN Dong +1 位作者 ZHOU Changqing PANG Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第3期327-335,共9页
Two well-preserved fossil dragonflies from the Late Mesozoic Yixian Formation, Liaoning Province, China are described and assigned to a new genus, Sopholibellula gen. nov. in Araripelibellulidae Bechly, 1996, closely ... Two well-preserved fossil dragonflies from the Late Mesozoic Yixian Formation, Liaoning Province, China are described and assigned to a new genus, Sopholibellula gen. nov. in Araripelibellulidae Bechly, 1996, closely related to the type genus Araripelibellula. This new genus differs from AraripelibeUula in the following characters: origins of RP and MA distinctly separated at arculus in both pairs of wings; anal loop wider and shorter, with Y-shaped veins inside; MA and IR2 not zigzag; several small intercalary veins present in the postdiscoidal area of hindwing; cells smaller and much more dense, especially in the apex and hind margin; bigger in size. Structures, including head, abdomen and parts of legs, were first described in details of this family. 展开更多
关键词 ODONATA ANISOPTERA Araripelibellulidae new genus FOSSIL Late Jurassic Early Cretaceous China
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A new genus and species of treefrog from Medog,southeastern Tibet,China(Anura,Rhacophoridae) 被引量:5
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作者 Ke JIANG Fang YAN +7 位作者 Kai WANG Da-Hu ZOU Cheng LI Jing CHE State Key Laboratory of Genetic Resources and Evolution,Kunming Institute of Zoology,Chinese Academy of Sciences Sam Noble Oklahoma Museum of Natural History and Department of Biology,University of Oklahoma Tibet University Imaging Biodiversity Expedition 《Zoological Research》 CAS CSCD 2016年第1期15-20,共6页
A new genus and species of threefrog is described from Medog, southeastern Tibet, China based on morphological and phylogenetic data. The new genus can be distinguished from other treefrog genera by the following comb... A new genus and species of threefrog is described from Medog, southeastern Tibet, China based on morphological and phylogenetic data. The new genus can be distinguished from other treefrog genera by the following combination of characters: (1) body size moderate, 45.0 mm in male; (2) snout rounded; (3) canthus rostralis obtuse and raised prominently, forming a ridge from nostril to anterior corner of eyes; (4) web rudimentary on fingers; (5) web moderately developed on toes; (6) phalange "Y" shaped, visible from dorsal side of fingers and toes; (7) skin of dorsal surfaces relatively smooth, scatted with small tubercles; (8) iris with a pale yellow, "X" shaped pattern of pigmentation. 展开更多
关键词 TAXONOMY New genus New species Theloderma moloch Nasutixalus medogensis sp. nov.
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Identification and Analysis of Genetic Diversity Structure Within Pisum Genus Based on Microsatellite Markers 被引量:4
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作者 ZONG Xu-xiao Rebecca Ford +2 位作者 Robert R Redden GUAN Jian-ping WANG Shu-min 《Agricultural Sciences in China》 CAS CSCD 2009年第3期257-267,共11页
To assesse the genetic diversity among wild and cultivated accessions of 8 taxonomic groups in 2 species, and 5 subspecies under Pisum genus, and to analyze population structure and their genetic relationships among v... To assesse the genetic diversity among wild and cultivated accessions of 8 taxonomic groups in 2 species, and 5 subspecies under Pisum genus, and to analyze population structure and their genetic relationships among various groups of taxonomy, the study tried to verify the fitness of traditionally botanical taxonomic system under Pisum genus and to provide essential information for the exploration and utilization of wild relatives of pea genetic resources. 197 Pisum accessions from 62 counties of 5 continents were employed for SSR analysis using 21 polymorphic primer pairs in this study. Except for cultivated field pea Pisum sativum ssp. sativum var. sativum (94 genotypes), also included were wild relative genotypes that were classified as belonging to P. fulvum, P. sativum ssp.abyssinicum, P. sativum ssp. asiaticum, P. sativum ssp. transcaucasicum, P. sativum ssp. elatius var. elatius, P. sativum ssp. elatius var. pumilio and P. sativum ssp. sativum var. arvense (103 genotypes). The PCA analyses and 3-dimension PCA graphs were conducted and drawn by NTSYSpc 2.2d statistical package. Nei78 genetic distances among groups of genetic resources were calculated, and cluster analysis using UPGMA method was carried out by using Popgene V1.32 statistical package, the dendrogram was drawn by MEGA3.1 statistical package. Allelic statistics were carried out by Popgene V1.32. The significance test between groups of genotypes was carried out by Fstat V2.9.3.2 statistical package. 104 polymorphic bands were amplified using 21 SSR primer pairs with unambiguous unique polymorphic bands. 4.95 alleles were detected by each SSR primer pair in average, of which 65.56% were effective alleles for diversity. PSAD270, PSAC58, PSAA18, PSAC75, PSAA175 and PSAB72 were the most effective SSR pairs. SSR alleles were uniformly distributed among botanical taxon units under Pisum genus, but significant difference appeared in most pairwise comparisons for genetic diversity between taxon unit based groups of genetic resources. Genetic diversity level of wild species P. fulvum was much lower than the cultivated species P. sativum. Under species P. sativum, P. sativum ssp. sativum var. sativum and P. sativum ssp. asiaticum were the highest in gentic diversity, followed by P. sativum ssp. elatius var. elatius and P. sativum ssp. transcaucasicum, P. sativum ssp. elatius var. pumilio, P. sativum ssp. sativum vat. arvense and P. sativum ssp. abyssinicum were the lowest. Four gene pool clusters were detected under Pisum genus by using PCA analysis. Gene pool "fulvum" mainly consisted of wild species Pisum fulvum, gene pool "abyssinicum" mainly consisted of P. sativum ssp. abyssinicum, and gene pool "arvense" mainly consisted of P. sativum ssp. sativum var. arvense. While gene pool "sativum" were composed by 5 botanical taxon units, they are P. sativum ssp. asiaticum, P. sativum ssp. elatius var. elatius, P. sativum ssp. transcaucasicum, P. sativum ssp. elatius var. pumilio and P. sativum ssp. sativum var. sativum. "sativum" gene pool constructed the primary gene pool of cultivated genetic resources; "fulvum" gene pool, "abyssinicum" gene pool and "arvense" gene pool together constructed the secondary gene pool of cultivated genetic resources. Pairwise Nei78 genetic distance among botanical taxon based groups of pea genetic resources ranged from 7.531 to 35.956, 3 large cluster groups were identified based on the UPGMA dendrogram. Group Ⅰ equals to "sativum" and "arvense" gene pools, Group Ⅱ equals to "abyssinicum" gene pool, and Group Ⅲ equals to "fulvum" gene pool. The UPGMA clustering results generally supporting the PCA clusting results. There were significant differences among most botanical groups under Pisum genus, with clear separation of four gene pools for genetic diversity structure. The research results partially support the traditional botanical taxonomy under Pisum genus, and pointed out its advantage and shortcoming. In order to broaden the genetic bases of pea varieties, the genetic potentials in the four gene pools should be thoroughly exploited. 展开更多
关键词 Pisum genus SSR genetic diversity botanical taxonomy gene pool
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One new genus and three new species of wingless grasshoppers from Xizang,China(Orthoptera:Acridoidea) 被引量:2
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作者 Zhe-Min Zheng Li-Liang Lin +1 位作者 Hong-Li Zhang Hui-Hua Zeng 《动物分类学报》 CSCD 北大核心 2014年第2期263-268,共6页
One new genus and three new species of wingless grasshoppers, i.e, Pseudozubovskia gen. nov., Pseudozubovskia xizangensis sp. nov., Eokingdonella gongbugyanda Sla. nov., Dysanema magna sp. nov. are described. The type... One new genus and three new species of wingless grasshoppers, i.e, Pseudozubovskia gen. nov., Pseudozubovskia xizangensis sp. nov., Eokingdonella gongbugyanda Sla. nov., Dysanema magna sp. nov. are described. The type specimens are deposited in the Institute of Zoology, Shaanxi Normal University. 展开更多
关键词 ORTHOPTERA ACRIDOIDEA wingless grasshopper new genus new species.
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Taxonomic Revision of the Genus <i>Pistacia</i>L. (Anacardiaceae) 被引量:2
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作者 Mohannad G. AL-Saghir Duncan M. Porter 《American Journal of Plant Sciences》 2012年第1期12-32,共21页
Pistacia is an economically important genus because it contains the pistachio crop, P. vera, which has edible seeds of considerable commercial importance whose value has increased over the last two decades reaching an... Pistacia is an economically important genus because it contains the pistachio crop, P. vera, which has edible seeds of considerable commercial importance whose value has increased over the last two decades reaching an annual value of about $2 billion (harvested crop). The taxonomic relationships among its species are controversial and not well under- stood due to the fact that they have no genetic barriers. The taxonomy of this genus is revised in detail through our re- search. It includes the following taxa: Pistacia atlantica Desf., P. chinensis Bunge subsp. chinensis, P. chinensis subsp. falcata (Bess. ex Martinelli) Rech. f., P. chinensis subsp. integerrima (J.L. Stew. ex Brandis) Rech. f., P. eurycarpa Yalt., P. khinjuk Stocks, P. lentiscus L. subsp. lentiscus, P. lentiscus subsp. emarginata (Engl.) AL-Saghir, P. mexicana Humb., Bonpl., & Kunth, P. X saportae Burnat, P. terebinthus L., P. vera L., and P. weinmannifolia Poiss. ex Franch. The genus is divided into two sections: section Pistacia and section Lentiscella. A key to the 14 taxa that have been recognized by this study is included. The new combination P. lentiscus subsp. emarginata (Engl.) AL-Saghir is made, and the names P. chinensis subsp. integerrima (J. L. Stew. ex Brandis) Rech. F., P. terebinthus L., and P. vera L. are lectotypified. 展开更多
关键词 Taxonomy Phylogeny PISTACIA ANACARDIACEAE genuS PISTACIA VERA
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Genus Distributions of M(o|¨)bius Ladders 被引量:4
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作者 李德明 《Northeastern Mathematical Journal》 CSCD 2005年第1期70-80,共11页
The genus distribution of a graph is a polynomial whose coefficients are the partition of the number of embeddings with respect to the genera. In this paper, the genus distribution of Mobius ladders is provided which ... The genus distribution of a graph is a polynomial whose coefficients are the partition of the number of embeddings with respect to the genera. In this paper, the genus distribution of Mobius ladders is provided which is an infinite class of 3-connected simple graphs. 展开更多
关键词 genus distribution semi-relative embedding Mobius ladder generating function
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Proximal tibial osteotomy for genu varum:Radiological evaluation of deformity correction with a plate vs external fixator 被引量:1
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作者 S Ali Ghasemi David T Zhang +1 位作者 Austin Fragomen S Robert Rozbruch 《World Journal of Orthopedics》 2021年第3期140-151,共12页
BACKGROUND High tibial osteotomy(HTO)is a well-known procedure for the correction of knee varus.The purpose of this study was to compare the radiological results and accuracy of deformity correction performed using tw... BACKGROUND High tibial osteotomy(HTO)is a well-known procedure for the correction of knee varus.The purpose of this study was to compare the radiological results and accuracy of deformity correction performed using two different techniques:acute opening wedge correction using a plate and gradual correction with a monolateral external fixator.AIM To compare of the radiological results of two different techniques:acute opening wedge correction(a plate and screw)and gradual correction(external fixator).METHODS A total of 43 patients with plates and 36 patients with external fixators were included.All patients had moderate uniplanar varus deformities.We measured radiographic parameters,including the mechanical axis deviation(MAD),medial proximal tibial angle(MPTA),Caton-Deschamps Index(CDI),posterior proximal tibial angle,and joint line obliquity angle(JLOA).The accuracy of MAD correction was calculated based on a correction goal of neutral or overcorrection for medial compartment arthritis.RESULTS Demographics including age,body mass index,sex,and preoperative deformities were similar between the groups.The MAD significantly improved from 23.6 mm medial to the midline(SD=8.2 mm)to 6.9 mm lateral to the midline(SD=5.4 mm)(P<0.001).The accuracy of MAD correction did not differ between the groups and was 96.1%(SD=8.1%)in the plate group and 98.2%(SD=5.2%)in the external fixator group(P=0.18).The MPTA significantly improved from 83.9°(SD=2.9°)to 90.9°(SD=3.3°)(P<0.001),and the change was similar between the groups.Differences were noted in patella height,with a CDI change of-19.2%(SD=13.7%)and 3.1%(SD=8.0%)for the plate and external fixator groups,respectively(P<0.001).The change in JLOA was 1.6 degrees(SD=1.1 degrees)and 0.9 degrees(SD=0.9 degrees)for the plate and external fixator groups,respectively(P=0.04).CONCLUSION Reliable correction of moderate varus alignment was achieved with both the acute opening wedge technique with a plate and the gradual monolateral external fixator technique.The patellar height decreased with the open wedge plate technique.Joint line obliquity decreased to a greater degree with the open wedge plate technique,perhaps as a result of medial collateral ligament release.The appropriate technique should be selected based on surgeon and patient preferences;however,external fixation may be a better choice when the preservation of patellar height is deemed important. 展开更多
关键词 High tibial osteotomy External fixator Gradual correction Plate and screw genu varum RADIOLOGICAL
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Latitudinal trends in genus richness of vascular plants in the Eocene and Oligocene of North America 被引量:1
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作者 AJ.Harris Cassondra Walker +1 位作者 Justin R.Dee Michael W.Palmer 《Plant Diversity》 SCIE CAS CSCD 北大核心 2016年第3期133-141,共9页
The latitudinal richness gradient is a frequent topic of study on the modern landscape,but its history in deep time is much less well known.Here,we preliminarily evaluated the paleolatitudinal richness gradient of vas... The latitudinal richness gradient is a frequent topic of study on the modern landscape,but its history in deep time is much less well known.Here,we preliminarily evaluated the paleolatitudinal richness gradient of vascular plants for the Eocene(56-33.9 million years ago) and Oligocene(33.9-23 million years ago) epochs of North America north of IVlexico using 201 fossil floras.We calculated the direction and shape of the gradient using quadratic regression to detect linear and curvilinear trends.We performed regressions for the Eocene and Oligocene as well as for informal time intervals within the Eocene:early,middle,and middle + late.We found that quadratic models better explain the data than linear models for both epochs as well as for the early Eocene.A roughly linear trend in the middle and middle + late intervals may reflect limited sampling of high latitude floras for those times.The curvilinear relationship was weak for the Eocene and the model showed a peak in richness at 45.5°N.The curvilinear relationship was much stronger for the Oligocene and the peak occurred at 48.5°N.In the Eocene,the mid-latitude peak in richness may be explained by mean annual temperature,which was probably higher at some mid-latitudes than at lower ones.For the Oligocene,the peak in richness at midlatitudes may be explained by evolutionary diversification within the temperate zone or by increased aridity at low latitudes.We also assessed the latitudinal richness gradient of genera within modern floras in North America north of Mexico and we found a weak,curvilinear trend with a peak in richness at 31.5°N.Our results suggest that the latitudinal genus richness gradient of vascular plants in North America continued to develop into its modern structure following the Oligocene. 展开更多
关键词 EOCENE genus richness North America OLIGOCENE PALEOLATITUDE Vascular plants
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A newly recorded genus of the Rhamphothrips genus-group (Thysanoptera: Thripidae) from China 被引量:1
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作者 Majid Mirab-Balou Shu-Lan Yang +1 位作者 Jia-Qian Gao Xiao-Li Tong 《Zoological Systematics》 CSCD 北大核心 2014年第4期583-587,共5页
The genus Parexothrips Priesner of Rhamphothrips genus-group(Thripidae: Thripinae) is recorded in China for the first time. A new record species, Parexothrips tenellus(Priesner), is described and illustrated from... The genus Parexothrips Priesner of Rhamphothrips genus-group(Thripidae: Thripinae) is recorded in China for the first time. A new record species, Parexothrips tenellus(Priesner), is described and illustrated from China. A key to genera of Chinese Rhamphothrips genus-group is provided. Examined specimens are deposited in the Insect Collection of Department of Entomology, South China Agricultural University(SCAU). 展开更多
关键词 THRIPS Rhamphothrips genus-group Parexothrips new record China
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New Genus of the Subfamily Geotrupinae (Coleoptera:Scarabaeoidea:Geotrupindae) from the Jehol Biota 被引量:1
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作者 Georgiy V. NIKOLAJEV REN Dong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第4期673-675,共3页
Parageotrupes incanus gen. et sp. nov. (Scarabaeoidea: Geotrupidae: Geotrupinae) is described and illustrated from the Yixian Formation of western Liaoning province, China.
关键词 COLEOPTERA FOSSIL SCARABAEOIDEA GEOTRUPIDAE Geotrupinae new genus new species Yixian Formation China
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A New Cockroach Genus of the Family Fuziidae from Northeastern China(Insecta:Blattida) 被引量:1
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作者 GUO Yinxia REN Dong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第2期501-506,共6页
A new genus and two new species of fossil Fuziidae are described and illustrated: Parvifuzia gen. nov., P. marsa sp. nov. and P. brava sp. nov.. Both species were collected from the Middle Jurassic Jiulongshan, Forma... A new genus and two new species of fossil Fuziidae are described and illustrated: Parvifuzia gen. nov., P. marsa sp. nov. and P. brava sp. nov.. Both species were collected from the Middle Jurassic Jiulongshan, Formation of Daohugou, Inner Mongolia of China. In conjunction with Fuzia Vr(s)ansk(y),Liang et Ren, 2009, the present findings allow us to demonstrate that members of the family were morphologically diverse, with body length ranging from medium (17 mm) in Fuzia to small (9.7 mm) in the present genus. Wing venation of F. dadao is complicated, but simple in the present species, and apex of male's cerci are sharp and forceps-like in F. dadao, but strongly curved inward and round in the new genus. 展开更多
关键词 Blattida=Blattaria=Blattodea Fuziidae new genus new species Middle Jurassic China
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GENETIC DIVERSITY OF FIVE FRESHWATER MUSSELS IN GENUS ANODONTA (MOLLUSCA: BIVALVIA) REVEALED BY RAPD ANALYSIS 被引量:1
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作者 WEI Kai-Jian, XIONG Bang-Xi and ZHANG Gui-Rong (College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China) 《水生生物学报》 CAS CSCD 北大核心 2006年第6期684-691,共8页
Unionidae are an important group of benthic freshwater species. Due to the convergence phenomenon within freshwater mussels, there is still much controversy in the classification of Chinese Unionidae. In China, most s... Unionidae are an important group of benthic freshwater species. Due to the convergence phenomenon within freshwater mussels, there is still much controversy in the classification of Chinese Unionidae. In China, most studies on freshwater mussels emphasized resource investigation, biology and morphology, while little has been done in genetics, and particularly not in population genetic structure as well as genetic diversity. In order to further understand the status of genetic diversity of different species, random amplified polymorphic DNA (RAPD) markers were used to detect genetic diversity of populations in five species of the genus Anodonta: Anodonta arcaeformis, A. arcaeformis flavotincta, A. fluminea, A. woodiana woodiana and A. w.pacifica. DNA extraction method was based on phenol-chloroform and extracted genomic DNA from the adductor muscle and mantle tissues. Sixteen random primers were used for RAPD amplification and the polymorphism of amplified loci were analyzed. The results demonstrated that the percentage of amplified polymorphic loci for various populations ranged from 34.5% to 62.8%, the mean Shannon’s genetic diversity indices ranged from 0.2021 to 0.3552, and the mean intra-population Nei’s genetic distance ranged from 0.1386 to 0.1713. In all populations of the five species, the genetic diversity for A. arcaeformis was the largest, and that of A. fluminea was the lowest. The inter-population genetic distance between A. w. woodiana and A. w. pacifica was 0.3186, so they can be considered as two sister species at the genetic angle. 展开更多
关键词 genus Anodonta Chinese unionidae Genetic diversity RAPD analysis
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