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Circumscriptions and Phylogenetic Relationships of Primula Sects. Auganthus and Ranunculoides: Evidence from nrDNA ITS Sequences 被引量:3
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作者 郝刚 胡启明 李南淑 《Acta Botanica Sinica》 CSCD 2002年第1期72-75,共4页
The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. W... The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. We conducted a phylogenetic analysis using sequences from the ITS region of nuclear ribosomal DNA. All five species of these two sections and some representatives of other related sections were sampled. The ITS trees show that P. filchnerae could be convincingly placed in sect. Auganthus , together with P. sinensis Sabine ex Lindl. and P. rupestris Balf. f. et Farrer, whereas sect. Ranunculoides contains two species: P. cicutariifolia Pax and P. merrilliana Schltr. These two sections are distantly related and their association with other sections needs further studies. This study also demonstrated that ITS sequences would be a suitable marker for the reconstruction of Primula phylogeny. 展开更多
关键词 PRIMULA sect. Auganthus sect. Ranunculoides PHYLOGENY ITS PRIMULACEAE
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基于Adh基因家族序列的牡丹组(Sect.MoutanDC.)种间关系 被引量:38
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作者 林启冰 周志钦 +2 位作者 赵宣 潘开玉 洪德元 《园艺学报》 CAS CSCD 北大核心 2004年第5期627-632,共6页
测定了牡丹组 7个种 10个野生居群共 10份样品的全部Adh1A、Adh1B和Adh2基因序列。结合前人已报道的牡丹野生种的Adh基因序列 ,以芍药组 (Sect .Paeonia)和北美芍药组 (Sect.Oneapia)的种作外类群 ,用PAUP (4 0b 4a)计算机程序构建了... 测定了牡丹组 7个种 10个野生居群共 10份样品的全部Adh1A、Adh1B和Adh2基因序列。结合前人已报道的牡丹野生种的Adh基因序列 ,以芍药组 (Sect .Paeonia)和北美芍药组 (Sect.Oneapia)的种作外类群 ,用PAUP (4 0b 4a)计算机程序构建了牡丹组全部 8个种的Adh1A、Adh1B和Adh2基因树 (最大简约树和邻接树 ) ,同时进行了Adh1A、Adh1B和Adh2基因序列的合并分析。结果表明 ,牡丹组的 8个种分为两个具有 90 %以上自展值支持的单系分支 ,分别对应Stern (194 6 )根据形态划分的革质花盘亚组 (Subsect .Vaginatae)和肉质花盘亚组 (Subsect.Delavayanae)。在革质花盘亚组内 ,本研究结果支持银屏牡丹 (Paeoniasuffruticosassp .yinpingmudan)和凤丹 (P .ostii)、紫斑牡丹 (P .rockii)和四川牡丹 (P .decomposita)以及矮牡丹 (P .jishanensis)和卵叶牡丹 (P .qiui)各种之间有更近的亲缘关系 ,但有关牡丹复合体 (P .suffruticosacomplex)内各种间更进一步的关系还有待进一步研究。根据Adh基因树并结合前人的结果对牡丹组的种间关系进行了详细的讨论。 展开更多
关键词 Adh基因家族 基因序列 牡丹组 sect.MoutanDC. 种间关系
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知识联盟中的知识创新过程研究——对SECT模型的再认识 被引量:4
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作者 胡延平 刘晓敏 《经济与管理》 2008年第7期31-34,共4页
SECT模型只是对知识创新过程中的知识客体演变运动的轨迹进行刻画,而没有深入分析完成从知识转移到知识创新这一过程的主体——组织和个人进行知识创新的实际过程,同时,"场"理论中过于强调隐性只是与显性知识的区别,而没有看... SECT模型只是对知识创新过程中的知识客体演变运动的轨迹进行刻画,而没有深入分析完成从知识转移到知识创新这一过程的主体——组织和个人进行知识创新的实际过程,同时,"场"理论中过于强调隐性只是与显性知识的区别,而没有看到两者之间的联系,将知识创新过程分割地对应于不同阶段。基于不同等级和等级对知识划分,结合单环学习、双环学习与再学习的知识创新的一般过程,对SECT模型和"场"理论进行了修正,说明知识创新需经历SECT模型的不同阶段和相应"场"情景支持,但每阶段都会产生隐性知识和显性知识。 展开更多
关键词 知识创新 sect模型 “场”理论
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Fruit Anatomy of sect. Paracamellia with Reference to Their Significance of Germplasm Resources Exploitation 被引量:1
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作者 洪思思 张斯敏 +3 位作者 楼嘉 张薇 吕洪飞 廖芳蕾 《Agricultural Science & Technology》 CAS 2011年第5期643-646,共4页
[Objective] To utilize the germplasm resources,new systematic evidence for the classification of sect.Paracamellia,genus Camellia is found in this article.[Method] Fruit anatomy of 10 species representing sect.Paracam... [Objective] To utilize the germplasm resources,new systematic evidence for the classification of sect.Paracamellia,genus Camellia is found in this article.[Method] Fruit anatomy of 10 species representing sect.Paracamellia was investigated.And the main component of sect.Paracamellia in the genus Camellia was studied by MVSP software.[Result] The exocarp was thin;mesocarp was broad,having a large number of stone cells;endocarp was lignified,and separated easily from seed.The principle components analysis suggested that the distance between species was far,showing far relation;the current study did not support the formation of Camellia grijsii(C.grijsii)and Camellia yuhsienensis(C.yuhsienensis),Camellia shensiensis(C.shensiensis)should not be recognized as a variety of C.yuhsienensis.In addition,it also proved Ming's combining of Camellia confusa(C.confusa)and Camellia kissi(C.kissi)was unnatural.[Conclusion] The study provided theoretical basis for the development and application of sect.Paracamellia in the genus Camellia. 展开更多
关键词 Genus Camellia sect.Paracamellia Fruit anatomy Classification Germplasm resources
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Distribution of Sect.Thea (L.) Dyer in Yunnan Province
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作者 汪云刚 刘本英 +7 位作者 宋维希 马玲 蒋会兵 矣兵 唐一春 李友勇 孙雪梅 王平盛 《Agricultural Science & Technology》 CAS 2011年第7期1067-1070,共4页
Yunnan is not only the center of tea origination but also the center of tea evolution and variation.There is a broad distribution of Sect.Thea(L.) Dyer in Yunnan.This paper concerns the research progress of Sect.The... Yunnan is not only the center of tea origination but also the center of tea evolution and variation.There is a broad distribution of Sect.Thea(L.) Dyer in Yunnan.This paper concerns the research progress of Sect.Thea(L.) Dyer,reveals the distribution of Sect.Thea(L.) Dyer in Yunnan,and checks out the number and name of Sect.Thea(L.) Dyer in Yunnan,which will offer references for further study and application of tea plants. 展开更多
关键词 YUNNAN sect.Thea(L.) Dyer DISTRIBUTION Species and Variety
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Evaluation of cotton germplasm for morphological and biochemical host plant UPdates resistance traits against sucking insect pests complex 被引量:2
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作者 RIZWAN Muhammad ABRO Saifullah +4 位作者 ASIF Muhammad Usman HAMEED Amjad MAH BOOB Wajid DEHO Zaheer Ahmed SIAL Mahboob Ali 《Journal of Cotton Research》 2021年第3期211-218,共8页
Background:Sucking insect pests cause severe damage to cotton crop production.The development of insect resistant cotton cultivars is one of the most effective measures in curtailing the yield losses.Considering the r... Background:Sucking insect pests cause severe damage to cotton crop production.The development of insect resistant cotton cultivars is one of the most effective measures in curtailing the yield losses.Considering the role of morphological and biochemical host plant resista nee(HPR)traits in plant defense,12 cotton genotypes/varieties were evaluated for leaf area,leaf glanding,total soluble sugars,total soluble proteins,total phenolics,tannin and total flavonoids against fluctuating populations of whitefly,thrips and jassid under field conditions.Results:The population of these insects fluctuated during the growing seas on and remained above threshold level(whitefly>5,thrips>(8-10)f or jassid>1 per leaf)during late June and early July.Strong and negative association of whitefly(r=-0.825)and jassid(r=-0.929)with seed cotton yield was observed.Mean population of insects were the highest in Glandless-1 followed by NIA-82 and NIA-M30.NIAB-Kiran followed by NI AB-878 and Sadori were the most resistant,with the mean population of 1.41,1.60,1.66(whitefly);2.24,232,2.53(thrips)and 037,0.31,036(jassid),respectively.The resistant variety NIAB-Kiran showed less soluble sugars(8.54 mg.g^(-1)),soluble proteins(27.11 mg.g^(-1))and more phenolic(36.56 mg.g^(-1))and flavonoids(13.10mg.g^(-1))as compared with the susceptible check Glandless-1.Moreover,all insect populations were positively correlated with total soluble sugars and proteins.Whitefly populations exhibited negative response to leaf gossypol glands,total phenolics,tannins and flavonoids.The thrips and jassid populations had a significant and negative correlation with these four biochemical HPR traits.Conclusion:The ide ntified resistant resources and HPR traits can be deployed against sucking in sect pests'complex in future breeding programs of developing insect resistant cotton varieties. 展开更多
关键词 GOSSYPIUM Insect resistance Plant defense Plant breeding Resistant traits Sucking in sects
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Cytotaxonomy and Cytogeography of Vicia sect. Vicilla in Northeast of China
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作者 刘祥君 张大维 李瑞军 《Journal of Forestry Research》 SCIE CAS CSCD 1998年第1期19-26,共8页
Vicia amirensis has pollen grain with swollen mesocipium, terete style, abaxially sprouting stylar hairs and globes stigma, differing from other five species,V. amoena, V. japonica, V. pseudo-orbus, V. ramuliflora, V.... Vicia amirensis has pollen grain with swollen mesocipium, terete style, abaxially sprouting stylar hairs and globes stigma, differing from other five species,V. amoena, V. japonica, V. pseudo-orbus, V. ramuliflora, V. unijuga andV. venosa, in sect.Vicilla of Kupicha’s System. This result further support taxonomic treatmentV. amurensis proposed by Endo and Ohash. The chromosome numbers of 64 populations and karyotypes of 15 populations for sect.Vicilla and sect.Amurense were observed.V. amurensis andV. psendo-orbus have similar karyotype features such as the same karyotype symmetry, comparable chromosome size and the same type, of Sat-chromosomes, and thereforeV. amurensis in seet.Amurense is assumed to be closely related toV. japonica in sect.Vicilla. The primary study of nuclear DNA amount was carried out on nine populations of six taxa in sect.Vicilla in China. It is primarily discussed that evolutionary trend of karyotype, nuclear DNA amount in sect.Vicilla and geographic distribution of different ploidy cytotypes. 展开更多
关键词 Vicia sect.Vicilla sect.Amurense KARYOTYPE Nuclear DNA content CYTOGEOGRAPHY CYTOTAXONOMY
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基于meat grinder with SECT电路的50kJ电感储能型脉冲电源的研究 被引量:5
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作者 班瑞 于歆杰 +1 位作者 刘旭堃 李臻 《电工电能新技术》 CSCD 北大核心 2017年第12期53-58,共6页
电感储能型脉冲电源是目前电磁发射技术的研究热点,提升装置储能密度对于推动电感储能型脉冲电源的应用和研究具有重要意义。本文介绍了一种适用于电感储能型脉冲电源的名为meat grinder with SECT的新电路,并对该电路进行了详细的原理... 电感储能型脉冲电源是目前电磁发射技术的研究热点,提升装置储能密度对于推动电感储能型脉冲电源的应用和研究具有重要意义。本文介绍了一种适用于电感储能型脉冲电源的名为meat grinder with SECT的新电路,并对该电路进行了详细的原理分析,指出该电路兼具电流关断能力强和拓扑结构简单的优点。通过仿真将meat grinder with SECT和STRETCH meat grinder、STRETCH meat grinder with ICCOS这两种主流电路进行了性能比较,发现meat grinder with SECT电路在保持电气性能不变的同时,成本最低,体积最小。基于meat grinder with SECT电路,本文研制了50k J电感储能型脉冲电源并进行了试验测试,测试结果达到了预期目标。 展开更多
关键词 电感储能型脉冲电源 MEAT GRINDER with sect 电磁发射 脉冲电源
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中国茜草属sect.Oligoneura的形态计量学研究 被引量:1
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作者 杨丽娥 孟盈 +1 位作者 聂泽龙 孙航 《广西植物》 CSCD 北大核心 2017年第7期829-840,共12页
茜草属为茜草科模式属,全球约80种,中国有近一半的物种,是茜草属的重要分布中心,大部分隶属于sect.Oligoneura。但是,该组内各种间的形态特征错综复杂,依靠单个性状不易划定种间界限。该研究在全面衡量sect.Oligoneura组内各种间形态特... 茜草属为茜草科模式属,全球约80种,中国有近一半的物种,是茜草属的重要分布中心,大部分隶属于sect.Oligoneura。但是,该组内各种间的形态特征错综复杂,依靠单个性状不易划定种间界限。该研究在全面衡量sect.Oligoneura组内各种间形态特征的基础上,选取该组20种共171份标本,对其3个数量性状和28个定性性状进行聚类分析和主成分分析。结果表明:在主成分分析中,前3个主成分累积贡献率有46.88%,性状的累积贡献率增长并不明显,但该结果仍与聚类分析结果一致。对前3个主成分贡献较大的特征包括叶形(叶长宽比)、叶柄长度、叶脉、每轮叶片数和生活型等,这些形态性状也是该属传统分类学中重要的物种鉴定特征。该研究结果与分子系统发育结果基本一致,支持该组内ser.Chinenses、R.mandersii group、R.angustissima group和R.siamensis group类群的划分,但并不支持ser.Cordifoliae单独成系。sect.Oligoneura内除少数物种外,大部分物种界限均比较清晰。形态计量学研究为sect.Oligoneura甚至茜草属的物种鉴定与划分提供了重要的参考意义。 展开更多
关键词 茜草属 sect.Oligoneura 聚类分析 主成分分析
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Establishing in Shandong:A Study on the Relationship Between the American Board of Commissioners for Foreign Missions and the Folk Secret Sects in Shandong
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作者 LI Nan 《Cultural and Religious Studies》 2022年第7期379-384,共6页
In the northwest of Shandong Province during Late Qing Dynasty,the struggle for survival among the villagers became social norm due to the fragility of the natural ecology,which was not only an important cause of loca... In the northwest of Shandong Province during Late Qing Dynasty,the struggle for survival among the villagers became social norm due to the fragility of the natural ecology,which was not only an important cause of local social unrest,but also complicated social relations.The potential anti-government tendencies of folk secret sects made them the targets of Qing government’s crackdown.In order to seek survival and development,the folk secret sects in northwest Shandong turned their eyes to Christian churches for political protect that was North China Mission of the American Board of Commissioners for Foreign Missions.With the help of secret sects,missionaries of the North China Mission gained a foothold in northwest Shandong.But they were not willing to provide political protect for secret sects.They only used the social ties of secret sects to wedge themselves into the rural society of northwest Shandong,hoping to establish Christian mission stations and develop Christian communities,not to integrate with secret sects. 展开更多
关键词 secret sect Ligua sect North China Mission American Board of Commissioners for Foreign Missions
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芍药属牡丹组(Paeonia sect.Moutan)种间关系的分子证据:GPAT基因的PCR-RFLP和序列分析 被引量:34
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作者 赵宣 周志钦 +2 位作者 林启冰 潘开玉 洪德元 《植物分类学报》 CSCD 北大核心 2004年第3期236-244,共9页
为了探讨芍药属牡丹组Paeoniasect.Moutan的种间关系 ,对采自 1 5个野生居群 ,代表牡丹组全部 8个野生种的 1 5份材料的GPAT基因片段 (外显子 5和 6之间 2kb的内含子 )进行了PCR_RFLP分析 ,并对代表牡丹组全部 8个野生种的 9份材料进行... 为了探讨芍药属牡丹组Paeoniasect.Moutan的种间关系 ,对采自 1 5个野生居群 ,代表牡丹组全部 8个野生种的 1 5份材料的GPAT基因片段 (外显子 5和 6之间 2kb的内含子 )进行了PCR_RFLP分析 ,并对代表牡丹组全部 8个野生种的 9份材料进行了测序。根据 1 2个限制性内切酶的PCR_RFLP数据 ,使用Network 3 .0计算机程序的RM (reduced_median)法建立了牡丹组种间亲缘关系网络树。同时根据 8个种 9份材料的GPAT基因片段序列 ,利用PAUP 4.0计算机程序建立了牡丹组GPAT基因的最大简约(MP)树和邻接 (NJ)树。结果获得了具有很高自展值支持、分辨良好的牡丹组种间关系 (GPAT基因 )树。最重要的是 ,该基因树所显示的牡丹组种间关系与根据形态学证据提出的牡丹组的种间关系基本吻合 ,并得到其他研究证据的支持。根据这一结果 ,对牡丹组的种间关系进行了详细的讨论。 展开更多
关键词 芍药属 牡丹组 野生居群 种间关系 GPAT基因 PCR-RFLP 序列分析
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SECT法电伴热系统漏电压的理论分析 被引量:1
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作者 邹玉民 戴琳 《油气储运》 CAS 北大核心 1992年第6期51-53,共3页
1 前言 SECT法(集肤电流加热法)具有结构简单、安全可靠、热效率高、易于实现自动控制等优点,因而在长输管线的伴热上得到了广泛地应用。 SECT法伴热系统是将SECT法加热管直接焊接到主管线上。
关键词 电加热 供热系统 漏泄电流 sect
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SECT法变频加热技术及其在集输管线上的应用 被引量:2
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作者 高大军 徐亚俊 陈秀和 《节能》 2001年第9期13-14,共2页
SECT法变频加热技术在原油集输管线上的应用与SECT法工频加热技术相比,可提高用电效率,以1km原油集输管线输入电流频率500Hz为例,节电率达23.2%,节能效果明显。
关键词 sect 变频加热 集输管线 节能 原油 电伴热 加热系统
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A revision of Clematis sect.Atragene(Ranunculaceae) 被引量:3
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作者 Wen-Jing YANG Liang-Qian LI Lei XIE 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第6期552-580,共29页
Clematis sect. Atragene is revised in this paper based on the examination of a large number of herbarium specimens, extensive field observations, and morphometric analyses. Brief taxonomic history and geographical dis... Clematis sect. Atragene is revised in this paper based on the examination of a large number of herbarium specimens, extensive field observations, and morphometric analyses. Brief taxonomic history and geographical distribution of the section are given, the relationships among the species are discussed, and the evolutionary trends of some characters in the section are evaluated. The staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing anthers. Subsequently, they may have evolved in two different ways. One possibility is that the staminodes elongate and become lanceolate, as long as sepals, and their apices turn into attenuate. The other is that the staminodes are spathulate, but not elongating, as long as stamens, and their apices turn into retuse from obtuse and rounded. The evolutionary trend of sepals may be from thin to thick in texture, and the veins from non-prominent to prominent. As a result, five new series are established and nine species, two subspecies and nine varieties (including three new ranks) are recognized in this section. An identification key is provided, and each taxon is described and illustrated. Clematis sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of, or few, overlapping distributions. Clematis fusijamana and Clematisfauriei are recognized as varieties of C. alpina ssp. ochotensis for the continuous variation of the velutinous strips on the sepal margins. Clematis iliensis is treated as variety of C. alpina ssp. sibirica for the continuous variation of leaf division types. Extensive variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis koreana. The North American ser. Occientales may be primitive, whereas ser. Macropetalae may be the most advanced taxon in this section. Ser. Alpinae and ser. Koreanae are closely related to each other. However, the systematic position of ser. Tomentosae cannot be determined based on morphological characters alone in the present study. 展开更多
关键词 CLEMATIS sect. Atragene RANUNCULACEAE taxonomic revision.
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Taxonomic revision of Lepisorus(J.Sm.) Ching sect.Lepisorus(Polypodiaceae) from China 被引量:2
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作者 Xin-Ping QI Xian-Chun ZHANG 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第6期581-598,共18页
The taxonomy of Lepisorus (J. Sm.) Ching sect. Lepisorus in China was revised based on herbarium specimen examinations, field observations, and microscopic study of rhizome scales, soral paraphyses, leaf epidermis, ... The taxonomy of Lepisorus (J. Sm.) Ching sect. Lepisorus in China was revised based on herbarium specimen examinations, field observations, and microscopic study of rhizome scales, soral paraphyses, leaf epidermis, and spores. As a result, nine species were recognized: Lepisorus macrosphaerus (Baker) Ching, Lepisorus asterolepis (Baker) Ching, Lepisorus marginatus Ching, Lepisorus kuchenensis (Y.C. Wu) Ching, Lepisorus megasorus (C. Chr.) Ching, Lepisorus kawakamii (Hayata) Tagawa, Lepisorus subsessilis Ching & Y.X. Lin, Lepisorus affinis Ching, and Lepisorus nudus (Hook.) Ching. Lepisorus kawakamii (Hayata) Tagawa was reinstated; Lepisorus gyirongensis Ching & S.K. Wu and Lepisorus longus Ching were reduced to synonyms ofL. nudus and L. affinis, respectively. The subdivision ofLepisorus macrosphaerus was not accepted. Rhizome scales and paraphyses are the most useful characters for species delimitation as well as for infrageneric classification. Characteristics of the leaf epidermis and spore ornamentation are usually stable and thus of great significance in understanding the relationships among groups within the genus. 展开更多
关键词 China LEPISORUS Lepisorus sect. Lepisorus POLYPODIACEAE taxonomic revision.
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A revision of Dryopteris sect.Diclisodon(Dryopteridaceae)based on morphological and molecular evidence with description of a new species 被引量:1
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作者 Zheng-Yu Zuo Ting Zhao +3 位作者 Xin-Yu Du Yun Xiong Jin-Mei Lu De-Zhu Li 《Plant Diversity》 SCIE CAS CSCD 2022年第2期181-190,共10页
Dryopteris sect.Diclisodon is a small section of ferns with about 12 species mainly distributed in East Asia.Here,we carried out morphological and phylogenetic analyses of this section.A new species from southwest Chi... Dryopteris sect.Diclisodon is a small section of ferns with about 12 species mainly distributed in East Asia.Here,we carried out morphological and phylogenetic analyses of this section.A new species from southwest China,D.gaoligongensis,is described and illustrated.Dryopteris gaoligongensis resembles D.indonesiana and D.sparsa,but differs by having a creeping rhizome and large 4-pinnate fronds.We also show that D.glabrior Ching&Z.Y.Liu is a distinct species;however,because it is a later homonym of D.glabrior Copel.,it should be renamed D.renchangiana.We conclude that a species previously known as D.nitidula,also an illegitimate homonym,should be recognized with a new name,D.sinonepalensis.We resolve the phylogenetic position of D.yoroii as sister to other sampled species of D.sect Diclisodon.Our phylogenetic analyses confirm the distinctiveness of D.gaoligongensis,D.renchangiana,and D.sinonepalensis.A key to species of D.sect Diclisodon in China is provided. 展开更多
关键词 Dryopteris gaotigongensis Dryopteris renchangiana Dryopteris sect.Nephrocystis Dryopteris sinonepalensis Molecular phylogeny Nomenclatural novelties
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Detection of Stego-Images in Communication among the Terrorist Boko-Haram Sect in Nigeria
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作者 Owoeye Kolade Ajayi Adedoyin Olayinka +2 位作者 Fadugba Sunday Obayomi Adesoji Isinkaye Folasade Olubusola 《Journal of Data Analysis and Information Processing》 2015年第4期168-174,共7页
Nigeria was listed as a part of terrorist states by United States of America as a result of Islamic group (Boko Haram Sect) attacks and other activities in the nation. It has also been discovered that the group emplo... Nigeria was listed as a part of terrorist states by United States of America as a result of Islamic group (Boko Haram Sect) attacks and other activities in the nation. It has also been discovered that the group employs “steganographic” schemes as a secure means for transmitting their hidden information to each other via Internet and social networks. The group has killed thousands of people since their increased insurgency in July, 2009. These challenges have affected the nation’s foreign policies, political and social economic developments. This research addresses the challenges by employing forensic technique using blind steganalysis approach to detect the presence of the hidden messages in images. Image Quality Metric is employed for extracting the features, and logistic regression is trained as the classifier to predict the stego-images. We show the effectiveness of the method by conducting test and analysis with 319 images varying in size and style. The result shows that the performance of the method is better than other steganalysis methods. 展开更多
关键词 Stego Staganalysis LOGISTIC Regression Boko-Haram sect
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积分代换x=a·sect使用条件的讨论
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作者 王丽艳 《承德石油高等专科学校学报》 CAS 1991年第1期48-50,共3页
在解决被积函数含有根式的积分问题时,常采用第二换元法,其中当被积函数所含根式为(x<sup>2</sup>-a<sup>2</sup>)<sup>1/2</sup>时,可命x=asect.通过这种三角代换消去根号,从而使问题获解.本文... 在解决被积函数含有根式的积分问题时,常采用第二换元法,其中当被积函数所含根式为(x<sup>2</sup>-a<sup>2</sup>)<sup>1/2</sup>时,可命x=asect.通过这种三角代换消去根号,从而使问题获解.本文就上述代换的使用条件进行一些讨论.为叙述方便,简单回顾一下第二换元条件: 展开更多
关键词 被积函数 sect x=a 换元法 三角代换 使用条件 单值对应 直角三角形法 取正 门单
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Gagyu Sect of Tibetan Buddhism
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作者 KUZHUB QOINPEI 《China's Tibet》 2001年第4期28-28,共1页
关键词 In Gagyu sect of Tibetan Buddhism
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Founder of the zhgung sect
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《China's Tibet》 2000年第1期28-28,共1页
关键词 Founder of the zhgung sect
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