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Taxonomy of Two New Peritrich Ciliates(Protozoa:Ciliophora)from Inland Saltwaters of China
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作者 YU Ying ZHANG Yong +2 位作者 LIANG Ziyao LI Jiqiu LIN Xiaofeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期811-821,共11页
The inland saltwater lakes harbor exceptional biodiversity.Here,two new species of solitary sessile peritrich ciliates were isolated from Qinghai Lake,the largest inland saltwater lake in China.Their morphology,ciliat... The inland saltwater lakes harbor exceptional biodiversity.Here,two new species of solitary sessile peritrich ciliates were isolated from Qinghai Lake,the largest inland saltwater lake in China.Their morphology,ciliature,silverline system,and molecular phylogeny were investigated based on live observation,silver staining,and analysis of the small subunit ribosomal DNA(SSU rDNA).Vorticella paraglobosa sp.n.is characterized mainly by its obconical or elongate bell-shaped zooid,C-shaped macronucleus,single ventrally located contractile vacuole,two-rowed infundibular polykinety 3,and 28-38 silverlines between peristome and aboral tro-chal band and 10-15 between aboral trochal band and scopula.Vorticella cotyliformis sp.n.differs from its congeners mainly by its double-layered peristomial lip,cup-shaped zooid,J-shaped macronucleus,single ventrally positioned contractile vacuole,three-rowed infundibular polykinety 3,and 70-85 silverlines between peristome and aboral trochal band and 21-25 between aboral trochal band and scopula.The SSU rDNA sequences of the two new species were obtained,and the subsequent molecular phylogenetic analysis supported their taxonomic classification. 展开更多
关键词 molecular phylogeny morphology new species Qinghai Lake taxonomy
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Molecular phylogeny and taxonomy of Phlomoides(Lamiaceae subfamily Lamioideae)in China:Insights from molecular and morphological data
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作者 Yue Zhao Ya-Ping Chen +8 位作者 Bryan T.Drew Fei Zhao Maryam Almasi Orzimat T.Turginov Jin-Fei Xiao Abdul G.Karimi Yasaman Salmaki Xiang-Qin Yu Chun-Lei Xiang 《Plant Diversity》 SCIE CAS CSCD 2024年第4期462-475,共14页
Phlomoides,with 150-170 species,is the second largest and perhaps most taxonomically challenging genus within the subfamily Lamioideae(Lamiaceae).With about 60 species,China is one of three major biodiversity centers ... Phlomoides,with 150-170 species,is the second largest and perhaps most taxonomically challenging genus within the subfamily Lamioideae(Lamiaceae).With about 60 species,China is one of three major biodiversity centers of Phlomoides.Although some Phlomoides species from China have been included in previous molecular phylogenetic studies,a robust and broad phylogeny of this lineage has yet to be completed.Moreover,given the myriad new additions to the genus,the existing infrageneric classification needs to be evaluated and revised.Here,we combine molecular and morphological data to investigate relationships within Phlomoides,with a focus on Chinese species.We observed that plastid DNA sequences can resolve relationships within Phlomoides better than nuclear ribosomal internal and external transcribed spacer regions(nrITS and nrETS).Molecular phylogenetic analyses confirm the monophyly of Phlomoides,but most previously defined infrageneric groups are not monophyletic.In addition,morphological analysis demonstrates the significant taxonomic value of eight characters to the genus.Based on our molecular phylogenetic analyses and morphological data,we establish a novel section Notochaete within Phlomoides,and propose three new combinations as well as three new synonyms.This study presents the first molecular phylogenetic analyses of Phlomoides in which taxa representative of the entire genus are included,and highlights the phylogenetic and taxonomic value of several morphological characters from species of Phlomoides from China.Our study suggests that a taxonomic revision and reclassification for the entire genus is necessary in the future. 展开更多
关键词 Lamioideae Molecular phylogenetics MORPHOLOGY Phlomideae taxonomy
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A Comparative Analysis of Cybersecurity Threat Taxonomies for Healthcare Organizations
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作者 Mahima Jaikanth Vijay K. Madisetti 《Journal of Software Engineering and Applications》 2024年第5期359-377,共19页
Information technology is critical in coordinating patient records, smart devices, operations, and critical infrastructure in healthcare organizations, and their constantly changing digital environment, including supp... Information technology is critical in coordinating patient records, smart devices, operations, and critical infrastructure in healthcare organizations, and their constantly changing digital environment, including suppliers, doctors, insurance providers, and regulatory agencies. This dependence on interdependent systems makes this sector vulnerable to various information technology risks. Such threats include common cybersecurity risks such as data breaches and malware attacks, unique problems occurring in healthcare settings such as unauthorized access to patient records, disruptions in services provided at medical facilities, and potential harm caused to patients due to the compromise of medical devices. The threat taxonomies, such as the Open Threat Taxonomy, NIST, or ENISA, are foundational frameworks for grasping and categorizing IT threats. However, these taxonomies were not specifically designed to deal with the complexities of the healthcare industry. The problem arises from the gap between these taxonomies’ general nature and the industry-specific threats and vulnerabilities that affect healthcare organizations. As a result, many healthcare institutions fail to holistically address and eliminate the unique risks related to confidentiality, integrity, and availability of patients’ data as well as critical systems used in healthcare. This paper aims to narrow this gap by carefully assessing these taxonomies to determine the frame-work best suited for addressing the threat environment in the healthcare sector. 展开更多
关键词 Threat Taxonomies Open Threat taxonomy (OTT)
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New record of the feather star Palaeocomatella hiwia(Echinodermata:Crinoidea:Comatulida)from Zhenbei Seamount in South China Sea:new insights into the taxonomic position of Palaeocomatella
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作者 Shao’e SUN Zijie MEI +2 位作者 Zhongli SHA Jing WANG Nansheng CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期244-251,共8页
One specimen belonging to the family Comatellinae was collected from the Zhenbei Seamount(332.5–478.2 m)in the South China Sea in July 2022.Based on the morphological characters,the specimen was identified as Palaeoc... One specimen belonging to the family Comatellinae was collected from the Zhenbei Seamount(332.5–478.2 m)in the South China Sea in July 2022.Based on the morphological characters,the specimen was identified as Palaeocomatella hiwia McKnight,1977.It is first recorded from China Sea and redescribed in detail.This specimen differs from the original description from New Zealand for never showing syzygy at br4+5 or br5+6 on interior and br1+2 on exterior arms.However,it is much conform to the redescription to specimens from Indonesia,with only differences in position of the second syzygy and distalmost pinnule comb.Specimen is deposited in the Institute of Oceanology,Chinese Academy of Sciences.Phylogenetic analyses based on the mitochondrial c oxidase subunit I(COI)and 16S rRNA genes indicated that P.hiwia was nested within the tribe Phanogeniini and clustered with Aphanocomaster pulcher.Furthermore,P.hiwia showed same morphological features in terms of mouth placement,comb location,and number of comb teeth rows as other genera of Phanogeniini.Therefore,we suggest that the genus Palaeocomatella should be put in the tribe Phanogeniini. 展开更多
关键词 new record Palaeocomatella hiwia McKnight 1977 South China Sea phylogenetic relationship taxonomy
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Molecular Phylogeny, Species Delimitation and Taxonomic Revision of the Australian Spider Wasp Genus Heterodontonyx Haupt, 1935 (Hymenoptera: Pompilidae)
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作者 Mahin Sadat Chavoshi Jolfaei Juanita Rodriguez 《Advances in Entomology》 2024年第2期105-128,共24页
Heterodontonyx (Pompilidae: Pepsinae) is an understudied genus with Australasiandistribution and most species are endemic to Australia. There have recently been sometaxonomic changes involving the genera Heterodontony... Heterodontonyx (Pompilidae: Pepsinae) is an understudied genus with Australasiandistribution and most species are endemic to Australia. There have recently been sometaxonomic changes involving the genera Heterodontonyx and Cryptocheilus based on molecular and morphological evidence, however, phylogenetic relationships within Heterodontonyx, species delimitation and formal revision have not been conducted. Here, we construct a Maximum Likelihood phylogeny estimate of Heterodontonyx based on ITS1, 5.8S, ITS2 region of 30 samples representing seven Heterodontonyx morphospecies. bPTP species delimitation approach was employed and ultimately the taxonomic revision of the genus was carried out. Phylogenetic analyses strongly support the monophyly of Heterodontonyx and the species delimitation method recognizes eight species among which one new species is identified. 展开更多
关键词 Pompilidae taxonomy Australian Pomplids PHYLOGENETICS
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The Black-winged Monarch(Monarcha frater):Geographic variation,taxonomy,a"new"population,and an enduring mystery in migration
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作者 Leo Joseph Julian Teh +1 位作者 Paul Sweet Phil Gregory 《Avian Research》 SCIE CSCD 2023年第3期467-477,共11页
The Black-winged Monarch(Monarcha frater)inhabits low-mid elevation forests across New Guinea and far northeastern Australia.Of its four recognized subspecies,M.f.canescens is migratory,breeding in tropical north-east... The Black-winged Monarch(Monarcha frater)inhabits low-mid elevation forests across New Guinea and far northeastern Australia.Of its four recognized subspecies,M.f.canescens is migratory,breeding in tropical north-eastern Australia from approximately November–March.The non-breeding range of M.f.canescens,apart from some individuals overwintering in Australia,has been unknown for>100 years.Data from 194 New Guinean and Australian specimens and a literature review have not solved this mystery;the narrow latitudinal range of the intratropical migration may inhibit use of GPS loggers in resolving the migration route.Field work in central and western parts of southern New Guinea is needed.Specimen data,however,revealed an essentially overlooked population in north-western New Guinea east of the Bird's Head Peninsula phenotypically indistinguishable from nominate M.f.frater of that Peninsula.Future genomic analysis of the complex will be largely done from toepad skin because frozen tissue samples for DNA analysis exist only of four individuals of what we suggest should be elevated to species rank as M.periophthalmicus.We discuss how genomic analysis might distinguish among alternative taxonomic hypotheses of one,two or three species.We suggest English names for what we consider to be three diagnosable taxa worth recognizing at species rank in this group:Arfak Monarch corresponding to M.frater(Bird's Head Peninsula and the“new”population of north-western New Guinea);Pearly Monarch for M.canescens(Australia and still unknown non-breeding range),and Masked Monarch for M.periophthalmicus(including kunupi,elsewhere in New Guinea). 展开更多
关键词 AUSTRALIA MIGRATION monarch flycatcher Monarcha frater New Guinea taxonomy
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Phylogenomics and integrative taxonomy reveal two new species of Amana(Liliaceae)
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作者 Mei-Zhen Wang Xiao-Kai Fan +10 位作者 Yong-Hua Zhang Jing Wu Li-Mi Mao Sheng-Lu Zhang Min-Qi Cai Ming-Hong Li Zhang-Shi-Chang Zhu Ming-Shui Zhao Lu-Xian Liu Kenneth M.Cameron Pan Li 《Plant Diversity》 SCIE CAS CSCD 2023年第1期54-68,共15页
Until now the genus Amana(Liliaceae),known as ’East Asian tulips’,has contained just seven species.In this study,a phylogenomic and integrative taxonomic approach was used to reveal two new species,Amana nanyueensis... Until now the genus Amana(Liliaceae),known as ’East Asian tulips’,has contained just seven species.In this study,a phylogenomic and integrative taxonomic approach was used to reveal two new species,Amana nanyueensis from Central China and A.tianmuensis from East China.A.nanyueensis resembles Amana edulis in possessing a densely villous-woolly bulb tunic and two opposite bracts,but differs in its leaves and anthers.Amana tianmuensis resembles Amana erythronioides in possessing three verticillate bracts and yellow anthers,but differs in aspects of its leaves and bulbs.These four species are clearly separated from each other in principal components analysis based on morphology.Phylogenomic analyses based on plastid CDS further support the species delimitation of A.nanyueensis and A.tianmuensis and suggests they are closely related to A.edulis.Cytological analysis shows that A.nanyueensis and A tianmuensis are both diploid(2n=2x=24),different from A edulis,which is either diploid(northern populations) or tetraploid(southern populations,2n=4x=48).The pollen morphology of A.nanyueensis is similar to other Amana species(single-groove germination aperture),but A.tianmuensis is quite different because of the presence of a sulcus membrane,which creates the illusion of double grooves.Ecological niche modelling also revealed a niche differentiation between A.edulis,A.nanyueensis and A.tianmuensis. 展开更多
关键词 Amana edulis Parallel evolution PHYLOGENY Species concept taxonomy Tulip
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广西苦苣苔科植物一新种——平果报春苣苔 被引量:1
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作者 马虎生 陆昭岑 +1 位作者 许为斌 盘波 《广西植物》 CAS CSCD 北大核心 2024年第4期629-634,共6页
该文报道了广西苦苣苔科报春苣苔属(Primulina Hance)一新种——平果报春苣苔(Primulina pingguoensis H.S.Ma&B.Pan),该新种在形态学上与囊筒报春苣苔(P.carinata Y.G.Wei,F.Wen&H.Z.Lü)相似,但两者能明显区别,平果报春... 该文报道了广西苦苣苔科报春苣苔属(Primulina Hance)一新种——平果报春苣苔(Primulina pingguoensis H.S.Ma&B.Pan),该新种在形态学上与囊筒报春苣苔(P.carinata Y.G.Wei,F.Wen&H.Z.Lü)相似,但两者能明显区别,平果报春苣苔花冠裂片狭披针形至线型,长宽比大于2(vs.圆形至卵圆形,长宽比小于1.5),花冠内部具8~10条紫色条纹,与花冠同色,无明显导蜜线(vs.棕色条纹,与花冠不同色,具两条黄色导蜜线),花冠筒管状,腹面隆状,(vs.狭漏斗状,明显隆起,形成一清晰的龙骨),叶片椭圆形到宽卵形,(6.5~9.5)cm×(4.5~6.5)cm[vs.宽椭圆形到卵形,(4.0~5.0)cm×(3.0~4.0)cm],叶基部稍楔形(vs.圆形)。该新种目前只在模式产地一个较大的石灰岩溶洞及周边发现有分布,目前该溶洞内开始发展畜牧养殖,对该物种的生存空间带来压力。该文对该新种的分布区(EOO)和占有面积(AOO)分别进行了评估,认为根据现已知的居群和所受威胁情况,根据IUCN红色名录标准,可暂定为“极危(CR)”级别。该种作为传统中药,被当地居民用于新生儿去胎毒等,有一定的保护和利用价值,今后可进一步开展此物种的民族植物学和药用植物学研究。该种面临生境破坏和野外采挖的风险,因此很有必要开展迁地保护和野外回归等相关工作。与该种同一乡镇分布的物种紫麟报春苣苔(P.purpureokylin F.Wen,Yi Huang&W.C.Chou),后者花冠筒漏斗状,叶片深绿至紫色,叶两面具紫红色粗伏毛而明显区别;距离该种5 km内分布有小白花报春苣苔(P.alba R.F.Li&B.Pan),后者花明显小型,花冠筒状,纯白色,与该种相区别。通过比较该种与报春苣苔属其他物种,发现也有一些物种花筒或多或少有膨大,如浅黄报春苣苔(P.lutescens B.Pan&H.S.Ma)、粉花报春苣苔[P.roseoalba(W.T.Wang)Mich.Moller&A.Weber]、中华报春苣苔[P.dryas(Dunn)Mich.Moller&A.Weber]、多莛报春苣苔[P.polycephala(Chun)Mich.Moller&A.Weber]以及崀山报春苣苔[P.langshanica(W.T.Wang)Yin Z.Wang]等,初步推断报春苣苔属植物的花筒膨大可能与特定传粉者有关,然而这一假设需进一步的野外调查和实验论证。 展开更多
关键词 石灰岩地区 植物区系 报春苣苔属 囊筒报春苣苔 分类学
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EU Taxonomy:Overview of All“Green”Economic Activities as of June 2023
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作者 Knut Henkel Jenny Lay-Kumar 《Journal of Modern Accounting and Auditing》 2023年第3期73-81,共9页
In June,the EU Commission published an update of the economic activities that can be classified as“green”.The article provides an updated tabular overview of now 152 economic activities in total,covering 17 sectors.... In June,the EU Commission published an update of the economic activities that can be classified as“green”.The article provides an updated tabular overview of now 152 economic activities in total,covering 17 sectors.In particular,the table shows in which of the four different delegated regulations the technical screening criteria for the economic activities are located.These are necessary in order to determine whether a concrete economic activity is taxonomy aligned. 展开更多
关键词 EU sustainable finance taxonomy green SUSTAINABILITY OVERVIEW economic activities CSRD ESRS
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中国西藏发现麝鼩属(劳亚食虫目:鼩鼱科)两新物种
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作者 陈顺德 杨思雨 +7 位作者 青娇 范荣辉 唐刻意 廖锐 郭克疾 张梦斐 吴南飞 刘少英 《兽类学报》 CAS CSCD 北大核心 2024年第5期529-550,共22页
麝鼩属(Crocidura)是哺乳动物中物种数量最多的属。中国麝鼩属的分类存在诸多争议,需要进一步开展基础研究。本文整理了灰麝鼩(C.attenuata)、台湾灰麝鼩(C.tanakae)、安徽麝鼩(C.anhuiensis)、白尾梢大麝鼩(C.dracula)、大麝鼩(C.lasiu... 麝鼩属(Crocidura)是哺乳动物中物种数量最多的属。中国麝鼩属的分类存在诸多争议,需要进一步开展基础研究。本文整理了灰麝鼩(C.attenuata)、台湾灰麝鼩(C.tanakae)、安徽麝鼩(C.anhuiensis)、白尾梢大麝鼩(C.dracula)、大麝鼩(C.lasiura)、黑袍麝鼩(C.pullata)和2个疑似新种共8种大型麝鼩189号标本,比较了假剥制标本、头骨和牙齿形态,对测量数据进行了主成分分析(PCA)和判别分析(DA)。结合中国及邻近地区麝鼩属物种Cyt b基因的分子系统学和分子物种界定结果,我们描记了两个从中国西藏发现的麝鼩新种,即札达麝鼩Crocidura zhadaensis Chen,Wu et Liu,sp.nov.和墨脱麝鼩Crocidura medogensis Chen,Wu et Liu,sp.nov.。札达麝鼩的鉴定特征:头体长69~77 mm,尾长49~56 mm,颅全长20.04~20.74 mm。体色较浅,整体呈褐色。尾距尾基3/4长有稀疏的白色长针毛,尾末端形成短毛束。脑颅扁平,下关节面内侧卵圆孔大,第三上单尖齿(U3)明显大于第二上单尖齿(U2),第一上前臼齿(P4)原尖附近有一小凹陷。墨脱麝鼩的鉴定特征:头体长67~76 mm,尾长62~65 mm,颅全长20.33~22.21 mm。体色深,背毛深黑褐色,腹毛黑灰色;尾长,常超过头体长的85%;脑颅饱满,顶骨较隆起;第一上单尖齿(U1)最大,高度约是第二上单尖齿(U2)和第三上单尖齿(U3)的两倍;第一上臼齿(M1)的次尖舌面侧缘延展呈半月形;乳突明显。为进一步厘清中国麝鼩物种的分类和物种多样性,本文编制了它们的物种检索表。 展开更多
关键词 西藏 麝鼩 分类 形态学 小型兽类
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中国近海栉江珧属分类与地理分布研究进展
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作者 薛东秀 王海艳 +1 位作者 马兴浩 张涛 《海洋科学》 CAS CSCD 北大核心 2024年第4期122-129,共8页
本文收集了涉及中国栉江珧属(Atrina Gray,1842)分类和分布的文献,结合近年来栉江珧属分子生物学的研究结果以及野外调查情况,对栉江珧属种类和地理分布情况进行了系统的梳理,确定了中国共有7种栉江珧属贝类,并对其分类分歧进行了讨论;... 本文收集了涉及中国栉江珧属(Atrina Gray,1842)分类和分布的文献,结合近年来栉江珧属分子生物学的研究结果以及野外调查情况,对栉江珧属种类和地理分布情况进行了系统的梳理,确定了中国共有7种栉江珧属贝类,并对其分类分歧进行了讨论;概括各栉江珧属种类的地理分布,广东是中国近海栉江珧属物种多样性最丰富的省份,其次为广西壮族自治区。根据目前中国栉江属种类的资源现状,对栉江珧属种类的开发利用与保护提出了建议,以期为深入开展全国范围的栉江珧属生物多样性保护和可持续利用提供科学依据。 展开更多
关键词 栉江珧属(Atrina Gray 1842) 物种分类 地理分布 资源保护
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我国西沙群岛仙掌藻属Halimeda(绿藻门钙扇藻科)的分类学研究
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作者 丁兰平 王雨昕 +2 位作者 刘金梅 鲍时翔 黄冰心 《天津师范大学学报(自然科学版)》 CAS 北大核心 2024年第3期28-36,共9页
为了探究仙掌藻属(Halimeda)在我国的分布及其分类,利用形态学、解剖学以及分子系统发育学方法,对2019年6月采集于西沙群岛的仙掌藻属样品进行形态学观察和分子系统发育分析.基于形态特征和rbcL基因序列的系统发育分析结果,共鉴定出了4... 为了探究仙掌藻属(Halimeda)在我国的分布及其分类,利用形态学、解剖学以及分子系统发育学方法,对2019年6月采集于西沙群岛的仙掌藻属样品进行形态学观察和分子系统发育分析.基于形态特征和rbcL基因序列的系统发育分析结果,共鉴定出了4个物种,即大叶仙掌藻(Halimeda macroloba)、仙掌藻(H. opuntia)、厚节仙掌藻(H. incrassata)和裂圆仙掌藻(新拟名)(H. monile).其中,H. monile为我国新纪录种,其主要特征为藻体节片分枝三裂,节片呈圆柱状,外层囊胞脱钙后不分离.在此基础上,分析仙掌藻属的属内组级系统以及属内其他相关物种间的关系,基于rbcL序列的分析结果显示,仙掌藻属物种(几乎涵盖了该属内的所有物种)形成了5个具有较好支持率的进化支. 展开更多
关键词 仙掌藻属 Halimeda monile RBCL 分类学 形态 西沙群岛
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中国红蒴真藓复合群和一个新记录种
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作者 刘永英 牛俊英 +2 位作者 唐启明 何文钏 韦玉梅 《广西植物》 CAS CSCD 北大核心 2024年第4期657-669,I0001-I0004,共17页
该研究以经典分类学方法探讨了中国红蒴真藓复合群(Bryum atrovirens Brid.complex),重点关注根生芽胞特征在分类中的价值。以期厘清中国红蒴真藓复合群的特征和物种组成;明确各物种之间的分类界限和地理分布。结果表明:(1)中国该复合... 该研究以经典分类学方法探讨了中国红蒴真藓复合群(Bryum atrovirens Brid.complex),重点关注根生芽胞特征在分类中的价值。以期厘清中国红蒴真藓复合群的特征和物种组成;明确各物种之间的分类界限和地理分布。结果表明:(1)中国该复合群共有9种,即毛状真藓(B.apiculatum Schw gr.)、红蒴真藓(B.atrovirens Brid.)、瘤根真藓(B.bornholmense Wink.&R.Ruthe)、棒槌真藓[B.clavatum(Schimp.)Müll.Hal.]、球根真藓(B.radiculosum Brid.)、齿缘真藓(B.rubens Mitt.)、沙氏真藓(B.sauteri Bruch&Schimp.)、星形真藓(B.stellituber Arts)和土生真藓(B.tuberosum Mohamed&Damanhuri),其中星形真藓为中国新分布种,首次观察到该种的孢子体以及红蒴真藓和齿缘真藓的中国标本产生根生芽胞。(2)该类群是适应临时环境的短命植物,主要通过根生芽胞进行无性繁殖,最主要的识别特征是芽胞的位置、颜色、形状、大小、细胞壁厚度和外层细胞是否突起及其程度等。(3)明确了每种的地理分布。综上所述,可根据根生芽胞的形态特征快速进行中国红蒴真藓复合群分类鉴定,新记录种的发现丰富了中国藓类植物新资料。 展开更多
关键词 星形真藓 根生芽胞 真藓属 新记录 分类
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主题方面共享的领域主题层次模型
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作者 万常选 张奕韬 +3 位作者 刘德喜 刘喜平 廖国琼 万齐智 《软件学报》 EI CSCD 北大核心 2024年第4期1790-1818,共29页
层次主题模型是构建主题层次的重要工具.现有的层次主题模型大多通过在主题模型中引入nCRP构造方法,为文档主题提供树形结构的先验分布,但无法生成具有明确领域涵义的主题层次结构,即领域主题层次.同时,领域主题不仅存在层次关系,而且... 层次主题模型是构建主题层次的重要工具.现有的层次主题模型大多通过在主题模型中引入nCRP构造方法,为文档主题提供树形结构的先验分布,但无法生成具有明确领域涵义的主题层次结构,即领域主题层次.同时,领域主题不仅存在层次关系,而且不同父主题下的子主题之间还存在子领域方面共享的关联关系,在现有主题关系研究中没有合适的模型来生成这种领域主题层次.为了从领域文本中自动、有效地挖掘出领域主题的层次关系和关联关系,在4个方面进行创新研究.首先,通过主题共享机制改进nCRP构造方法,提出nCRP+层次构造方法,为主题模型中的主题提供具有分层主题方面共享的树形先验分布;其次,结合nCRP+和HDP模型构建重分层的Dirichlet过程,提出rHDP(reallocated hierarchical Dirichlet processes)层次主题模型;第三,结合领域分类信息、词语语义和主题词的领域代表性,定义领域知识,包括基于投票机制的领域隶属度、词语与领域主题的语义相关度和层次化的主题-词语贡献度;最后,通过领域知识改进rHDP主题模型中领域主题和主题词的分配过程,提出结合领域知识的层次主题模型rHDP_DK(rHDP with domain knowledge),并改进采样过程.实验结果表明,基于nCRP+的层次主题模型在评价指标方面均优于基于nCRP的层次主题模型(hLDA,nHDP)和神经主题模型(TSNTM);通过rHDP_DK模型生成的主题层次结构具有领域主题层次清晰、关联子主题的主题词领域差异明确的特点.此外,该模型将为领域主题层次提供一个通用的自动挖掘框架. 展开更多
关键词 层次主题模型 领域分类信息 词语语义 主题关联关系 层次化的采样过程 领域主题层次
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因素空间理论下的因果概率推理分类算法研究
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作者 曾繁慧 胡光闪 +1 位作者 孙慧 汪培庄 《智能系统学报》 CSCD 北大核心 2024年第4期1042-1051,共10页
机器学习方法与因果推理结合能极大地提升方法性能。为探究因果概率正逆向推理的分类效果,基于因素空间理论下的因素概率论,利用条件概率,研究正向因素概率推理原理及模型并提出正向因果概率推理分类法(forward causal probabilistic in... 机器学习方法与因果推理结合能极大地提升方法性能。为探究因果概率正逆向推理的分类效果,基于因素空间理论下的因素概率论,利用条件概率,研究正向因素概率推理原理及模型并提出正向因果概率推理分类法(forward causal probabilistic inference classification algorithm,FCPIC)和简化条件的可取度分类法;研究逆向因素概率推理原理及模型并结合贝叶斯网络提出逆向因果概率推理分类法(reverse causal probabilistic inference classification algorithm,RCPIC)。将3个分类算法与KNN(K-Nearest neighbor)和SVM(support vector machine)算法进行实例对比验证,研究结果表明:FCPIC算法、可取度分类算法和RCPIC算法简单有效、具有可行性和实用性,且可取度分类法和RCPIC算法性能优于SVM和KNN算法,FCPIC算法对实际数据预测中必要类有查全需求的情况更优。研究结论丰富了因素空间的理论研究和应用价值。 展开更多
关键词 因素空间 因果概率推理分类法 可取度分类法 贝叶斯网络 因素概率论 条件概率 因果关系 人工智能
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评价支架如何影响在线同伴互评交互质量?——基于SOLO分类理论的视角分析
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作者 刘丹 张柏钰 李玉斌 《数字教育》 2024年第4期31-37,共7页
学习者充足的交互是保证同伴互评有效性的重要途径。为解决当前在线同伴互评中缺乏对同伴之间深度交互的引导,导致学习者交互处于较浅层级等问题,以SOLO分类理论为指导,围绕5种不同的思维水平设计评价支架,以“现代教育技术”课程为例,... 学习者充足的交互是保证同伴互评有效性的重要途径。为解决当前在线同伴互评中缺乏对同伴之间深度交互的引导,导致学习者交互处于较浅层级等问题,以SOLO分类理论为指导,围绕5种不同的思维水平设计评价支架,以“现代教育技术”课程为例,采用准实验研究法,对评价活动产生的交互文本进行量化内容分析,以及对学习者的作品改进情况进行分析,探究评价支架对在线同伴互评交互质量的影响。研究发现:(1)评价支架能够显著提升学习者参与互评活动的交互结果质量;(2)评价支架促进学习者的交互深度由浅层级向更深层级转化;(3)学习者对评价支架持认可态度,评价支架作为一种评价工具,可以有效指导互评活动,促进学习者自身的课程学习。 展开更多
关键词 同伴互评 SOLO分类理论 评价支架 交互深度
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叶灯鱼与异灯鱼两属鱼类的分类与仔稚鱼形态学比较
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作者 柳淑芳 刘巧红 +4 位作者 王焕 李昂 安长廷 万瑞景 庄志猛 《水产学报》 CAS CSCD 北大核心 2024年第9期99-112,共14页
叶灯鱼与异灯鱼两属鱼类在全球有道氏叶灯鱼、日本叶灯鱼和异灯鱼3个物种,隶属于灯笼鱼目、灯笼鱼科。目前我国仅在台湾省东部海域有日本叶灯鱼成鱼和仔稚鱼分布以及东海外海黑潮流域有被鉴定为隶属于叶灯鱼属的盖氏翼胸灯笼鱼后期仔鱼... 叶灯鱼与异灯鱼两属鱼类在全球有道氏叶灯鱼、日本叶灯鱼和异灯鱼3个物种,隶属于灯笼鱼目、灯笼鱼科。目前我国仅在台湾省东部海域有日本叶灯鱼成鱼和仔稚鱼分布以及东海外海黑潮流域有被鉴定为隶属于叶灯鱼属的盖氏翼胸灯笼鱼后期仔鱼和翼胸灯笼鱼稚鱼分布的记录。为厘清叶灯鱼和异灯鱼两属鱼类的分类地位与隶属关系,明确其发育形态,本文在归纳两属鱼类分类要点、构建分类检索表的基础上,对1984年6—7月(夏季)和1984年12月—1985年1月(冬季)于东海外海黑潮流域两个航次调查采集的仔稚鱼样品再次整理,将原被鉴定为盖氏翼胸灯笼鱼和翼胸灯笼鱼的仔稚鱼分别订正为日本叶灯鱼与异灯鱼。描述了体长5.10 mm日本叶灯鱼后期仔鱼和6.80 mm异灯鱼稚鱼的形态特征,同时引述了日本叶灯鱼和道氏叶灯鱼仔稚鱼以及异灯鱼稚鱼的发育形态。通过比较3种仔稚鱼的发育形态特征,明确了翼状胸鳍是它们区别于其他硬骨鱼类仔稚鱼的独特形态特征;发现仔稚鱼体表黑色素的形状和数量与不同地理群体的发育生物学和生境有关,而黑色素的分布趋势具有物种特异性,可作为物种鉴别的形态学依据之一;还明确了稚鱼发育过程中鳃盖条区发光器的发育顺序与分布位置。同时,综合分析各大洋的仔稚鱼分布资料,提出道氏叶灯鱼仔稚鱼在西北太平洋分布的可能性很小的见解;根据黑潮流域的冬、春、夏季均有日本叶灯鱼生殖群体进行产卵繁殖,提出日本叶灯鱼的繁殖生物学及其种群动力学需要深入调查与研究的科学问题。研究结果提高了我国对叶灯鱼和异灯鱼两属鱼类的认知及对这3种仔稚鱼的鉴别能力,丰富了灯笼鱼科鱼类早期生活史研究的内涵,为今后开展相关海洋生态调查的仔稚鱼种类鉴别提供了理论依据,也为灯笼鱼等小型鱼类的资源养护提供了重要参考。 展开更多
关键词 日本叶灯鱼 道氏叶灯鱼 异灯鱼 分类 仔稚鱼 发育形态
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基于SOLO分类理论测评科学思维的基因工程试题命制策略
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作者 甘耀平 《生物学教学》 北大核心 2024年第7期59-61,共3页
在分析SOLO分类理论与科学思维水平关联性的基础上,运用SOLO分类理论命制基因工程试题以测评科学思维水平,为高中生物学教学和命题提供参考。
关键词 SOLO分类理论 科学思维 基因工程 试题命制
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浅谈白僵菌的分类
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作者 魏万勇 蒲涛 +1 位作者 陈雪 刘渝铃 《果树资源学报》 2024年第1期101-103,114,共4页
白僵菌应用非常广泛,既可作为一种真菌杀虫剂,也应用于白僵蚕人工饲养。众多文献研究涉及白僵菌,但关于其分类很不统一甚至混乱。真菌分类系统复杂多样,形态学特征是传统分类学的主要依据,结合微生物分类学的不断发展,提出了白僵菌传统... 白僵菌应用非常广泛,既可作为一种真菌杀虫剂,也应用于白僵蚕人工饲养。众多文献研究涉及白僵菌,但关于其分类很不统一甚至混乱。真菌分类系统复杂多样,形态学特征是传统分类学的主要依据,结合微生物分类学的不断发展,提出了白僵菌传统分类存在的一些问题及其多样的分类依据,并进行了探讨。 展开更多
关键词 白僵菌 微生物分类学 形态特征 分类系统 分类
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卷积神经网络的可解释性研究综述 被引量:10
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作者 窦慧 张凌茗 +2 位作者 韩峰 申富饶 赵健 《软件学报》 EI CSCD 北大核心 2024年第1期159-184,共26页
神经网络模型性能日益强大,被广泛应用于解决各类计算机相关任务,并表现出非常优秀的能力,但人类对神经网络模型的运行机制却并不完全理解.针对神经网络可解释性的研究进行了梳理和汇总,就模型可解释性研究的定义、必要性、分类、评估... 神经网络模型性能日益强大,被广泛应用于解决各类计算机相关任务,并表现出非常优秀的能力,但人类对神经网络模型的运行机制却并不完全理解.针对神经网络可解释性的研究进行了梳理和汇总,就模型可解释性研究的定义、必要性、分类、评估等方面进行了详细的讨论.从解释算法的关注点出发,提出一种神经网络可解释算法的新型分类方法,为理解神经网络提供一个全新的视角.根据提出的新型分类方法对当前卷积神经网络的可解释方法进行梳理,并对不同类别解释算法的特点进行分析和比较.同时,介绍了常见可解释算法的评估原则和评估方法.对可解释神经网络的研究方向与应用进行概述.就可解释神经网络面临的挑战进行阐述,并针对这些挑战给出可能的解决方向. 展开更多
关键词 神经网络 可解释性 分类 深度学习
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