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Lotic specialization in modern Asian newts(Caudata:Salamandridae):Phylogeny,historical biogeography,and ancestral traits based on combined DNA data
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作者 Yan-Peng Shen Kanto Nishikawa +5 位作者 Jian-Ping Jiang Masafumi Matsui Ding-Qi Rao Natsuhiko Yoshikawa Atsushi Tominaga Daosavanh Sanamxay 《Zoological Research:Diversity and Conservation》 2024年第3期191-200,共10页
Pachytriton,and Paramesotriton,are primarily distributed across East Asia,displaying a broad range of environmental adaptations,including generalists inhabiting both lotic and lentic habitats and lotic specializations... Pachytriton,and Paramesotriton,are primarily distributed across East Asia,displaying a broad range of environmental adaptations,including generalists inhabiting both lotic and lentic habitats and lotic specializations.Despite recent studies on their biogeographic history,how these species adapted to geographical changes remains unclear.In this study,divergence times and reconstructed ancestral traits were estimated based on phylogenetic analysis of mitochondrial and nuclear DNA sequences,totaling 4048 bp.Results indicated that the divergence between lotic-specialized and generalist species occurred during the middle to late Miocene(95% confidence interval(CI):16-13 million years ago(Ma)),correlating with the long-lasting arid period(14-12 Ma)and uplift of the Wuyi-Nanling mountains(15-11 Ma).Ancestral trait reconstruction revealed notable morphological changes associated with the emergence of lotic-specialized lineages.Specifically,male body size increased from 130 mm to 140 mm,and epibranchial traits shifted from thin to thick structures.Additionally,variation in tongue movability and skin texture were observed among lotic species.Each morphological shift is hypothesized to have an ecological basis,facilitating adaptation to specific environmental conditions.Overall,this study represents the first comprehensive attempt to elucidate the evolution of ancestral traits among divergent species of modern Asian newts,providing a deeper understanding of their adaptive responses to historical geographical and climatic changes. 展开更多
关键词 Modern Asian newts PHYLOGENY Divergence time Trait reconstruction
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中文科技政策文本分类:增强的TextCNN视角 被引量:8
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作者 李牧南 王良 赖华鹏 《科技管理研究》 CSSCI 北大核心 2023年第2期160-166,共7页
近年尽管针对中文本文分类的研究成果不少,但基于深度学习对中文政策等长文本进行自动分类的研究还不多见。为此,借鉴和拓展传统的数据增强方法,提出集成新时代人民日报分词语料库(NEPD)、简单数据增强(EDA)算法、word2vec和文本卷积神... 近年尽管针对中文本文分类的研究成果不少,但基于深度学习对中文政策等长文本进行自动分类的研究还不多见。为此,借鉴和拓展传统的数据增强方法,提出集成新时代人民日报分词语料库(NEPD)、简单数据增强(EDA)算法、word2vec和文本卷积神经网络(TextCNN)的NEWT新型计算框架;实证部分,基于中国地方政府发布的科技政策文本进行算法校验。实验结果显示,在取词长度分别为500、750和1000词的情况下,应用NEWT算法对中文科技政策文本进行分类的效果优于RCNN、Bi-LSTM和CapsNet等传统深度学习模型,F1值的平均提升比例超过13%;同时,NEWT在较短取词长度下能够实现全文输入的近似效果,可以部分改善传统深度学习模型在中文长文本自动分类任务中的计算效率。 展开更多
关键词 NEWT 深度学习 数据增强 卷积神经网络 政策文本分类 中文长文本
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Description of a New Species of the Asian Newt Genus Tylototriton sensu lato(Amphibia:Urodela:Salamandridae) from Southwest China 被引量:2
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作者 Shize LI Gang WEI +2 位作者 Yanlin CHENG Baowei ZHANG Bin WANG 《Asian Herpetological Research》 SCIE CSCD 2020年第4期282-296,共15页
The newt genus Tylototriton sensu lato is widely distributed in Eastern,Southeastern and Southern Asia.Previous studies indicated that there still has been several cryptic species in the group.Here,we describe a new s... The newt genus Tylototriton sensu lato is widely distributed in Eastern,Southeastern and Southern Asia.Previous studies indicated that there still has been several cryptic species in the group.Here,we describe a new species of the genus from Guizhou Province,China.Phylogenetic analyses based on mitochondrial DNA supported that the new species was resolved as an independent clade nested into the Tylototriton sensu lato clade.On morphology,the new species could be distinguished from its congeners by a combination of the following characters:large body size(SVL 76.8-85.2 mm in male and 76.3-87.4 mm in female);head longer than wide;snout truncate in dorsal view;tail length longer than the snout-vent length in males;the distal digit ends,ventral digits,peripheral area of cloaca and the tail s lower margin are orange;relative length of toesⅢ> Ⅳ> Ⅱ> Ⅰ> Ⅴ;the distal tips of the limbs greatly overlapping when the fore and hind limbs are pressed along the trunk;fingertips reach the level beyond the snout when the forelimbs are stretched forward. 展开更多
关键词 China molecular phylogenetic analysis new species newts taxonomy
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A new species of the genus Tylototriton (Amphibia: Urodela: Salamandridae) from the Eastern Dalou Mountains in Guizhou, China 被引量:2
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作者 Tao Luo Shasha Yan +3 位作者 Ning Xiao Wei Li Huaiqing Deng Jiang Zhou 《Zoological Systematics》 CSCD 2022年第1期66-88,共23页
A new newt species,Tylototriton daloushanensis Zhou,Xiao&Luo,sp.nov.,is described from Guizhou,China,based on phylogenetic and morphological analyses.Phylogenetic analyses based on mitochondrial 16S and ND2 genes ... A new newt species,Tylototriton daloushanensis Zhou,Xiao&Luo,sp.nov.,is described from Guizhou,China,based on phylogenetic and morphological analyses.Phylogenetic analyses based on mitochondrial 16S and ND2 genes show that the new species is an independent lineage closely related to T.maolanensis,T.broadoridgus,T.dabienicus,T.anhuiensis,and T.wenxianensis.Morphologically,the new species is distinguished from its congeners by a combination of the following morphological characters:(1)large body size(SVL 64.7–83.6 mm in male and 70.5–100.3 mm in female);(2)head longer than wide,prominent bony ridges present;(3)snout rounded in dorsal view;(4)tail length less than snoutvent length in both males and females;(5)dark black body coloration,except for bright orange cranial region,palms and soles,vent region,and ventral ridge of tail;(6)relative length of toes Ⅲ>Ⅳ>Ⅱ>Ⅰ>Ⅴ;(7)fingertips reaching to between the eyes and nostrils when the forelimbs are stretched forward;(8)distal tip of the limbs greatly overlapping when the fore and hind limbs are pressed along the trunk;(9)presence of gular fold;(10)vertebral ridge slightly segmented,slightly flattened rib nodules,indistinct interspaces between rib nodules;and(11)lacking orange color markings on posterior parotoids and rib nodules.The found of the new species suggests that the species diversity of the genus Tylototriton may be underestimated. 展开更多
关键词 Asian knobby newts SYSTEMATICS cryptic species taxonomy
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A New Newt of the Genus Cynops(Caudata: Salamandridae) from Guangdong, China 被引量:2
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作者 Zhiyong YUAN Ke JIANG +2 位作者 Limin DING Liang ZHANG Jing CHE 《Asian Herpetological Research》 SCIE 2013年第2期116-123,共8页
We describe a new species of the genus Cynops from northeastern Guangdong, China. This new species is distinguished from its congeners by a combination of morphological and molecular characters. In morphology, it is c... We describe a new species of the genus Cynops from northeastern Guangdong, China. This new species is distinguished from its congeners by a combination of morphological and molecular characters. In morphology, it is chra- cterized by distinctive irregular bluish grey spots on the dorsum from head to tail; irregular, bright orange blotches on venter, chin, underside of axillae, limbs, cloaca; one bright orange stripe in the middle of venter; and ventral tail orange red. Analyses of mitochondrial DNA data indicate that this new species forms one highly diverged lineage within the Chinese group of Cynops. 展开更多
关键词 CAUDATA SALAMANDRIDAE Cynops glaucus sp. nov. NEWT GUANGDONG molecular analysis
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Newt life after fish introduction: extirpation of paedomorphosis in a mountain fish lake and newt use of satellite pools 被引量:1
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作者 Mathieu DENOEL Patrick SCIME Nicola ZAMBELLI 《Current Zoology》 SCIE CAS CSCD 2016年第1期61-69,共9页
Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determine... Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determined whether small wetlands, such as pools surrounding fished and fishless lakes, could sustain paedomorphic and metamorphic newts. To this end, we surveyed lakes known historically to sustain Alpine newts Ichthyosaura alpestris as well as 35 nearby pools. On the basis of the published records, the only known population exhibiting paedomorphosis in the Swiss AIps was found to be extirpated by salmonid introductions. However, the metamorphs persisted in per- ipheral pools, paedomorphosis was discovered at a new locality, and overwintering larvae were still present in one of the lakes. These results show the importance of conserving varied aquatic habitats such as pools in mountainous environments where the main resources can become un- suitable for amphibians because of fish introductions. Pools may also function as reservoirs in maintaining newt populations until programs to remove fish from lakes can be carried out. It is not known if paedomorphs could reappear after fish removal. However, the combined resilience of am- phibians after fish removal and the genetic basis for paedomorphosis highlighted in other taxa by previous studies suggest that there is the potential to maintain this intraspecific case of diversity even after its disappearance. 展开更多
关键词 ALPS amphibian decline fish introduction mountain lake Alpine newt PAEDOMORPHOSIS pool wetland.
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Retinoid X receptor α downregulation is required for tail and caudal spinal cord regeneration in the adult newt 被引量:1
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作者 Sarah E.Walker Rachel Nottrodt +3 位作者 Lucas Maddalena Christopher Carter Gaynor E.Spencer Robert L.Carlone 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第6期1036-1045,共10页
Some adult vertebrate species,such as newts,axolotls and zebrafish,have the ability to regenerate their central nervous system(CNS).However,the factors that establish a permissive CNS environment for correct morphol... Some adult vertebrate species,such as newts,axolotls and zebrafish,have the ability to regenerate their central nervous system(CNS).However,the factors that establish a permissive CNS environment for correct morphological and functional regeneration in these species are not well understood.Recent evidence supports a role for retinoid signaling in the intrinsic ability of neurons,in these regeneration-competent species,to regrow after CNS injury.Previously,we demonstrated that a specific retinoic acid receptor(RAR)subtype,RARβ,mediates the effects of endogenous retinoic acid(RA)on neuronal growth and guidance in the adult newt CNS after injury.Here,we now examine the expression of the retinoid X receptor RXRα(a potential heterodimeric transcriptional regulator with RARβ),in newt tail and spinal cord regeneration.We show that at 21 days post-amputation(dpa),RXRαis expressed at temporally distinct periods and in non-overlapping spatial domains compared to RARβ.Whereas RARβprotein levels increase,RXRαproteins level decrease by 21 dpa.A selective agonist for RXR,SR11237,prevents both this downregulation of RXRαand upregulation of RARβand inhibits tail and caudal spinal cord regeneration.Moreover,treatment with a selective antagonist for RARβ,LE135,inhibits regeneration with the same morphological consequences as treatment with SR11237.Interestingly,LE135 treatment also inhibits the normal downregulation of RXRαin tail and spinal cord tissues at 21 dpa.These results reveal a previously unidentified,indirect regulatory feedback loop between these two receptor subtypes in regulating the regeneration of tail and spinal cord tissues in this regeneration-competent newt. 展开更多
关键词 retinoid X receptor spinal cord regeneration NEWT retinoic acid ependymoglia retinoic acid receptor
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Hepatoprotective Activity of Plant Peptides 被引量:1
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作者 O. G. Kulikova D. I. Maltsev +2 位作者 A. P. Ilyina V. P. Yamskova I. A. Yamskov 《American Journal of Plant Sciences》 2015年第7期848-855,共8页
Peptides (molecular weights are 1200 – 11,600 Da) biologically acting at concentration 10-8 - 10-15 mg/ml were obtained from leaves of dill Anethum graveolens L. and celandine Chelidonium majus L. by circular dichroi... Peptides (molecular weights are 1200 – 11,600 Da) biologically acting at concentration 10-8 - 10-15 mg/ml were obtained from leaves of dill Anethum graveolens L. and celandine Chelidonium majus L. by circular dichroism (CD) spectroscopy. We have shown that these peptides form second structure characterized by the prevalence of β-structures and coil in water solution. In model of organotypic roller culturing of triton liver in vitro, the ability of the peptides isolated from Anethum graveolens L. and Chelidonium majus L. at concentration 10-8 - 10-15 mg/ml to influence increasing of pigment cells, which provided protective function of organism, was demonstrated. 展开更多
关键词 PEPTIDES Medical Plants ORGANOTYPIC ROLLER CULTURING NEWT LIVER
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Histological Study of the Liver Pigmentation of Chinese Fire-bellied Newt (Cynops orientalis) During Activity and Hibernation Periods
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作者 Zhaohui XIE Haijun LI +3 位作者 Boying LI Linna CHENG Anfang ZHAO Cunshuan XU 《Asian Herpetological Research》 SCIE 2012年第4期322-326,共5页
The pigmentation in the liver of Chinese fire-bellied newt(Cynops orientalis) was described during two periods of the annual cycle(summer activity and winter hibernation). A large number of melanin granules were gathe... The pigmentation in the liver of Chinese fire-bellied newt(Cynops orientalis) was described during two periods of the annual cycle(summer activity and winter hibernation). A large number of melanin granules were gathered into clusters and distributed unevenly inside the pigment cells. Liver pigmentation(melanin content) was found unstable,varying during the annual cycle. During the hibernation period,pigmentation accumulation was shown to increase in the liver of the Chinese fire-bellied newt. Hepatocytes during the active period are approximately 14.64% larger than those in the hibernation period,while the nucleus is approximately 7.43% bigger during the active period when compared with that during the hibernation period. These findings indicate that variation in pigment distribution and hepatocyte morphology in Chinese fire-bellied newt liver may be an ecologically adaptive strategy to the adverse physiological conditions during hibernation. 展开更多
关键词 Chinese fire-bellied newt histology pigment cell hepatocyte seasonal variation
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摄像机识别钢轨故障
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《国际铁道工程》 2001年第4期52-52,共1页
关键词 摄像机 识别 钢轨故障 Newt国际公司
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