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c-Abl kinase at the crossroads of healthy synaptic remodeling and synaptic dysfunction in neurodegenerative diseases 被引量:2
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作者 Daniela A.Gutiérrez América Chandía-Cristi +2 位作者 María JoséYáñez Silvana Zanlungo Alejandra R.Alvarez 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期237-243,共7页
Our ability to learn and remember depends on the active formation,remodeling,and elimination of synapses.Thus,the development and growth of synapses as well as their weakening and elimination are essential for neurona... Our ability to learn and remember depends on the active formation,remodeling,and elimination of synapses.Thus,the development and growth of synapses as well as their weakening and elimination are essential for neuronal rewiring.The structural reorganization of synaptic complexes,changes in actin cytos keleton and organelle dynamics,as well as modulation of gene expression,determine synaptic plasticity.It has been proposed that dys regulation of these key synaptic homeostatic processes underlies the synaptic dysfunction observed in many neurodegenerative diseases.Much is known about downstream signaling of activated N-methyl-D-aspartate andα-amino-3-hydroxy-5-methyl-4-isoazolepro pionate receptors;howeve r,other signaling pathways can also contribute to synaptic plasticity and long-lasting changes in learning and memory.The non-receptor tyrosine kinase c-Abl(ABL1)is a key signal transducer of intra and extracellular signals,and it shuttles between the cyto plasm and the nucleus.This review focuses on c-Abl and its synaptic and neuronal functions.Here,we discuss the evidence showing that the activation of c-Abl can be detrimental to neurons,promoting the development of neurodegenerative diseases.Nevertheless,c-Abl activity seems to be in a pivotal balance between healthy synaptic plasticity,regulating dendritic spines remodeling and gene expression after cognitive training,and synaptic dysfunction and loss in neurodegenerative diseases.Thus,c-Abl genetic ablation not only improves learning and memory and modulates the brain genetic program of trained mice,but its absence provides dendritic spines resiliency against damage.Therefo re,the present review has been designed to elu cidate the common links between c-Abl regulation of structural changes that involve the actin cytos keleton and organelles dynamics,and the transc riptional program activated during synaptic plasticity.By summarizing the recent discove ries on c-Abl functions,we aim to provide an overview of how its inhibition co uld be a potentially fruitful treatment to improve degenerative outcomes and delay memory loss. 展开更多
关键词 actin cytoskeleton activity-dependent plasticity Alzheimer's disease C-ABL dendritic spines learning SYNAPSE synaptic plasticity TRANSCRIPTION tyrosine kinase
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日轮果属,越南唇形科黄芩亚科一新属
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作者 李波 Thanh Son HOANG +4 位作者 Maxim S.NURALIEV Vu Anh TAI Andrey N.KUZNETSOV Svetlana P.KUZNETSOVA 向春雷 《热带亚热带植物学报》 CAS CSCD 北大核心 2023年第5期727-735,共9页
描述并绘制了越南唇形科一新属及新种:日轮果属(Heliacria Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)和日轮果(H.maritima Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)。日轮果属因具攀援藤本习性,花大且花冠为纯白色,花萼近辐射对称、5... 描述并绘制了越南唇形科一新属及新种:日轮果属(Heliacria Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)和日轮果(H.maritima Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)。日轮果属因具攀援藤本习性,花大且花冠为纯白色,花萼近辐射对称、5深裂、裂片长且在果期增大并开展,果实顶端具放射状的瘤状突起等特征而明显区别于黄芩亚科的其他5属。目前,该属仅发现于越南东南部沿海的平定省、富安省、庆和省和宁顺省,常生于海岸边干旱的低地矮林中。 展开更多
关键词 新分类群 特有属 冬红属 膜萼藤属 唇形目
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Hiding on jagged karst pinnacles:A new microendemic genus and species of a limestone-dwelling agamid lizard(Squamata:Agamidae:Draconinae)from Khammouan Province,Laos 被引量:2
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作者 Saly Sitthivong Peter Brakels +6 位作者 Santi Xayyasith Nathanaël Maury Sabira Idiiatullina Parinya Pawangkhanant Kai Wang Tan Van Nguyen Nikolay A.Poyarkov 《Zoological Research》 SCIE CSCD 2023年第6期1039-1051,共13页
We describe a unique new species and genus of agamid lizard from the karstic massifs of Khammouan Province,central Laos.Laodracon carsticola Gen.et sp.nov.is an elusive medium-sized lizard(maximum snout-vent length101... We describe a unique new species and genus of agamid lizard from the karstic massifs of Khammouan Province,central Laos.Laodracon carsticola Gen.et sp.nov.is an elusive medium-sized lizard(maximum snout-vent length101 mm)specifically adapted to life on limestone rocks and pinnacles.To assess the phylogenetic position of the new genus amongst other agamids,we generated DNA sequences from two mitochondrial gene fragments(16S rRNA and ND2)and three nuclear loci(BDNF,RAG1 and c-mos),with a final alignment comprising 7418 base pairs for 64 agamid species.Phylogenetic analyses unambiguously place the new genus in the mainland Asia subfamily Draconinae,where it forms a clade sister to the genus Diploderma from East Asia and the northern part of Southeast Asia.Morphologically,the new genus is distinguished from all other genera in Draconinae by possessing a notably swollen tail base with enlarged scales on its dorsal and ventral surfaces.Our work provides further evidence that limestone regions of Indochina represent unique“arks of biodiversity”and harbor numerous relict lineages.To date,Laodracon carsticola Gen.et sp.nov.is known from only two adult male specimens and its distribution seems to be restricted to a narrow limestone massif on the border of Khammouan and Bolikhamxai provinces of Laos.Additional studies are required to understand its life history,distribution,and conservation status. 展开更多
关键词 Biodiversity ENDEMISM INDOCHINA Karstic landscape Laodracon carsticola Phylogeny Southeast Asia Taxonomy
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Mountain jade: A new high-elevation microendemic species of the genus Zhangixalus(Amphibia: Anura: Rhacophoridae)from Laos
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作者 Peter Brakels Tan Van Nguyen +4 位作者 Parinya Pawangkhanant Sabira S.Idiiatullina Sengvilay Lorphengsy Chatmongkon Suwannapoom Nikolay A.Poyarkov 《Zoological Research》 SCIE CAS CSCD 2023年第2期374-379,共6页
DEAR EDITOR,We report on a new species, Zhangixalus melanoleucus sp.nov., from Phou Samsoum Mountain(PSM) in Xiengkhouang Province, northeastern Laos, based on an integrative taxonomic approach, including morphologica... DEAR EDITOR,We report on a new species, Zhangixalus melanoleucus sp.nov., from Phou Samsoum Mountain(PSM) in Xiengkhouang Province, northeastern Laos, based on an integrative taxonomic approach, including morphological, molecular, and bioacoustic lines of evidence. Morphologically, the new species can be distinguished from its congeners by a combination of the following diagnostic characters: medium body size(SVL 34.4–36.3 mm in males, 53.7 mm in a single female);dorsum smooth and green;chest and belly lacking spots;flanks, axillae, ventral surfaces of forearms, inguinal. 展开更多
关键词 NORTHEASTERN Morphological SPOTS
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寄生小蜂对小青×黑杨树皮及杨圆蚧挥发油的行为反应(英文) 被引量:2
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作者 迟德富 Rafael Ocete Rubio +2 位作者 严善春 张丹丹 温振宏 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期255-259,共5页
采用四臂式嗅觉仪测定了长棒四节蚜小蜂(Pteroptrix longgiclava(Girault)(Hymenoptera:Aphelinidae))和黄胸扑虱蚜小蜂(Encarsia gigas(Tshumakova)(Hymenoptera:Aphelinidae)),对健康的小青×黑杨(Populus pseudo-simonii×... 采用四臂式嗅觉仪测定了长棒四节蚜小蜂(Pteroptrix longgiclava(Girault)(Hymenoptera:Aphelinidae))和黄胸扑虱蚜小蜂(Encarsia gigas(Tshumakova)(Hymenoptera:Aphelinidae)),对健康的小青×黑杨(Populus pseudo-simonii×P.nigra)树皮、被杨圆蚧(Quadraspidiotus gigas(Thiem & Gerneck))危害的杨树皮、杨圆蚧1齿固定若虫的虫体和介壳的挥发油的趋性反应。测定结果表明:被杨圆蚧危害后的小青×黑杨树皮和杨圆蚧1龄因定若虫的介壳对长棒四节蚜小蜂和黄胸扑虱蚜小蜂成虫具有较大的吸引力。3-7μL介壳挥发油和5-9μL受害杨树皮挥发油对长棒四节蚜小蜂的寄主搜寻行为具有较强的引导作用。虫体的挥发油对小蜂的寄生定位也起到了一定的引诱作用。两种小蜂对健康树皮的挥发油几乎没有反应。图4表1参20。 展开更多
关键词 寄生小蜂 长棒四节蚜小蜂 黄胸扑虱蚜小蜂 小青×黑杨 杨圆蚧 挥发油 趋性反应 寄主搜寻行为
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阿尔泰林蛙的物种有效性及其分类地位——来自系统发育分析的证据(英文) 被引量:6
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作者 杨军校 周炜帏 +3 位作者 饶定齐 POYARKOV A.Nikolay KUZMIN Sergius L 车静 《Zoological Research》 CAS CSCD 北大核心 2010年第4期353-360,共8页
为检验阿尔泰林蛙(Rana altaica)的系统发育地位及其物种有效性,该文运用线粒体细胞色素b基因,应用贝叶斯分析和最大简约方法构建了欧亚大陆分布的部分林蛙的系统发育关系。两种分析方法均支持阿尔泰林蛙在田野林蛙(R.arvalis)这一分支... 为检验阿尔泰林蛙(Rana altaica)的系统发育地位及其物种有效性,该文运用线粒体细胞色素b基因,应用贝叶斯分析和最大简约方法构建了欧亚大陆分布的部分林蛙的系统发育关系。两种分析方法均支持阿尔泰林蛙在田野林蛙(R.arvalis)这一分支的内部。单倍型网络图显示来自阿尔泰地区和中西伯利亚地区所谓的阿尔泰林蛙与田野林蛙有共享单倍型。通过该文母系遗传发育分析结果显示阿尔泰林蛙种级地位不成立,是田野林蛙的同物异名。另外,该文实验分析结果提示,对中国分布的林蛙内部种组划分应建立在系统进化关系的基础上重新进行评估。 展开更多
关键词 阿尔泰林蛙 田野林蛙 田野林蛙阿尔泰亚种 细胞色素B 群体扩张
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JAK-STAT pathway in carcinogenesis:Is it relevant to cholangiocarcinoma progression? 被引量:14
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作者 Olga V Smirnova Tatiana Yu Ostroukhova Roman L Bogorad 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第48期6478-6491,共14页
The features of JAK-STAT signaling in liver cells are discussed in the current review. The role of this signaling cascade in carcinogenesis is accentuated. The possible involvement of this pathway and alteration of it... The features of JAK-STAT signaling in liver cells are discussed in the current review. The role of this signaling cascade in carcinogenesis is accentuated. The possible involvement of this pathway and alteration of its elements are compared for normal cholangiocytes, cholangiocarcinoma predisposition and development. Prolactin and interleukin-6 are described in detail as the best studied examples. In addition, the non-classical nuclear translocation of cytokine receptors is discussed in terms of its possible implication to cholangiocarcinoma development. 展开更多
关键词 胆管癌 活化剂 催乳激素 治疗方法
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Discovery of Japalura chapaensis Bourret, 1937 (Reptilia: Squamata: Agamidae) from Southeast Yunnan Province, China 被引量:6
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作者 Kai Wang Ke Jiang +3 位作者 Yu-Fan Wang Nikolay A. Poyarkov Jr. Jing Che Cameron D. Siler 《Zoological Research》 SCIE CAS CSCD 2018年第2期105-113,共9页
Due to a paucity of surveys in northern Indochina and lack of international collaborations among neighboring countries, recognized distributional ranges for many amphibian and reptile species end at the political bord... Due to a paucity of surveys in northern Indochina and lack of international collaborations among neighboring countries, recognized distributional ranges for many amphibian and reptile species end at the political borders for some countries, despite seemingly continuous suitable habitat spanning the region. Combining both morphological and genetic data, we report the first discovery of Japalura chapaensis, a rare agamid lizard believed previously to be endemic to northern Vietnam only, along the border region of southeastern Yunnan Province, China. To facilitate future research on the genus Japalura sensu lato in Indochina, we provide detailed descriptions of additional specimens of this rare species, including the first description of coloration in life and an expanded diagnosis, and discuss the species boundary of J. chapaensis with respect to its congeners. 展开更多
关键词 Draconinae INDOCHINA MorphologicalVariation New record Range extension SYSTEMATICS Taxonomy
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A new species of Crocodile Newt, genus Tylototriton(Amphibia, Caudata, Salamandridae) from the mountains of Kachin State, northern Myanmar 被引量:2
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作者 Than Zaw Paw Lay +2 位作者 Parinya Pawangkhanant Vladislav A.Gorin Nikolay A.Poyarkov,Jr 《Zoological Research》 SCIE CAS CSCD 2019年第3期151-174,共24页
We describe a new species of the genus Tylototriton from Ingyin Taung Mt.,Mohnyin Township,Kachin State,Myanmar,based on morphological and molecular evidence.The new species is assigned to the subgenus Tylototriton s.... We describe a new species of the genus Tylototriton from Ingyin Taung Mt.,Mohnyin Township,Kachin State,Myanmar,based on morphological and molecular evidence.The new species is assigned to the subgenus Tylototriton s.str.and is clearly distinct from all known congeners by the following characters:medium body size;thin,long tail,lacking lateral grooves;rough skin;truncate snout;wide,protruding supratemporal bony ridges on head,beginning at anterior corner of orbit;weak,almost indistinct sagittal ridge;long,thin limbs,broadly overlapping when adpressed along body;distinct,wide,non-segmented vertebral ridge;13 or 14 rib nodules;brown to darkbrown background coloration with dull orange-brown to yellowish-brown markings on labial regions,parotoids,rib nodules,whole limbs,vent,and ventral tail ridge.We also briefly discuss biogeography and species diversity of the genus Tylototriton in Myanmar. 展开更多
关键词 Tylototriton kachinorum sp.nov. mtDNA GENEALOGY ND2 16S rRNA Shan Biogeography ENDEMISM Taxonomy
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Preparation,characterization and catalytic behavior of Pt-Cu nanoparticles in methane combustion 被引量:3
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作者 Florica Papa Catalin Negrila +2 位作者 Gianina Dobrescu Akane Miyazaki Ioan Balint 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第5期537-542,共6页
Fine and well dispersed Pt-Cu bimetallic nanoparticles stabilized by polyvinyl pyrrolidone (PVP) were synthesized by alkaline polyol method. The molar ratio of Pt to Cu was 1 : 1. Further, the Pt-Cu bimetallic nano... Fine and well dispersed Pt-Cu bimetallic nanoparticles stabilized by polyvinyl pyrrolidone (PVP) were synthesized by alkaline polyol method. The molar ratio of Pt to Cu was 1 : 1. Further, the Pt-Cu bimetallic nanoparticles were supported on alumina and their catalytic behavior in methane combustion was investigated. The as-prepared as well as the supported Pt-Cu nanoparticles were characterized by transmission elec- tron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), fractal analysis and X-ray diffraction (XRD). The dependence of methane combustion on the morphology and surface composition of Pt-Cu nanoparticles was analyzed based on the experimental results. 展开更多
关键词 Pt-Cu bimetallic catalyst methane combustion polyol method Pt-Cu nanoparticle
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Natural history of Valentin’s rock lizard(Darevskia valentini) in Armenia 被引量:1
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作者 Eduard Galoyan Alisa Bolshakova +4 位作者 Manush Abrahamyan Ruzanna Petrosyan Valeria Komarova Victor Spangenberg Marine Arakelyan 《Zoological Research》 SCIE CAS CSCD 2019年第4期277-292,共16页
Valentin's rock lizard (Darevskia valentini) is suggested to be the pare nt for several parthenoge netic species (e.g., D. armeniaca, D. bendimahiensis, D. sapphirina, and D. unisexualis) that evolved through hybr... Valentin's rock lizard (Darevskia valentini) is suggested to be the pare nt for several parthenoge netic species (e.g., D. armeniaca, D. bendimahiensis, D. sapphirina, and D. unisexualis) that evolved through hybridization. Complex evolutionary processes (ineluding reticulate evolution) are occurring within the areas where Valentin' s rock lizard coexists with these and other rock lizards. Hence, a detailed biological specification of this species is important for understanding how vertebrates evolve. Valentin's rock lizard is a longlived (up to 9 years), small diurnal lizard with larger females than males, which is unlike other species of the genus. Their relatively large eggs and early reproducti on period, which occurs just after emerge nee from winter shelters, are adaptatio ns for living in a high elevation climate (higher than 2 000 m a.s.l.). Their body temperatures (31 -32℃) are comparable to body temperatures of rock lizards living in milder climates, though female body temperature is more depe ndent on substrate temperature and basking due to their lower activity than that found in males. Population density fluctuates from several individuals to several hundred per hectare and is not affected by parthenogen coexistenee, although hybrids do occur in sexually biased populations where males are more common than females. The male home range is larger than that of females, though these home ranges broadly overlap. Prey is not limited in the mountain meadows and Valentin's rock lizards feed on a great variety of arthropods. Infan ticide occurs in high-de nsity populati ons. 展开更多
关键词 Darevskia valentini REPRODUCTION Population density SKELETOCHRONOLOGY Home range SEASONAL activity
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A new karst-dwelling bent-toed gecko (Squamata: Gekkonidae Cyrtodactylus) from Xiangkhoang Province, northeastern Laos 被引量:2
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作者 Roman A. Nazarov Olivier S.G. Pauwels +3 位作者 Evgeniy L. Konstantinov Anatoliy S. Chulisov Nikolai L. Orlov Nikolay A. Poyarkov, Jr. 《Zoological Research》 SCIE CAS CSCD 2018年第3期202-219,共18页
We describe a new karst-dwelling Cyrtodactylus from Ban Thathom, Xiangkhoang Province, northeastern Laos. The new species can be distinguished from other congeners by having four dark dorsal bands between limb inserti... We describe a new karst-dwelling Cyrtodactylus from Ban Thathom, Xiangkhoang Province, northeastern Laos. The new species can be distinguished from other congeners by having four dark dorsal bands between limb insertions, a discontinuous nucha~ loop, 10 precloacal pores in males or 10-12 precloacal pits (females) separated by a diastema from a series of enlarged femoral scales bearing 18 or 19 pores (male) or 8-10 pits (females) along each femur, 14-18 dorsal tubercle rows at midbody, no precloacal groove, 30-36 midbody scale rows across belly between ventrolateral skin folds, transversely enlarged subcaudal plates, and a maximal known snout-vent length of 75.5 mm. Our description brings to 22 the number of Cyrtodactylus species recorded from Laos. 展开更多
关键词 Indochinese region KARST Limestone Herpetology Taxonomy New species
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A new species of genus Fejervarya (Anura:Dicroglossidae) from northern Thailand 被引量:2
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作者 Chatmongkon SUWANNAPOOM Zhi-Yong YUAN +4 位作者 Nikolay A.POYARKOV Jr. Fang YAN Somboon KAMTAEJA Robert W.MURPHY Jing CHE 《Zoological Research》 CAS CSCD 2016年第6期327-337,共11页
We describe a new species of frog in the dicroglossid genus Fejervarya from Ban Monjong, Omkoi District, Chiang Mai Province, northern Thailand. Analysis of DNA sequence data from the mitochondrial gene 16S, advertise... We describe a new species of frog in the dicroglossid genus Fejervarya from Ban Monjong, Omkoi District, Chiang Mai Province, northern Thailand. Analysis of DNA sequence data from the mitochondrial gene 16S, advertisement calls, and morphological distinctiveness support recognition of the new species. Matrilineal genealogy suggests that the new population from Chiang Mai is a sister taxon to the South Asian clade that includes F. syhadrensis, F. granosa, and F. pierreL The new species, Fejervarya chiangmaiensis sp. nov., differs morphologically from its congeners by its relatively small body size and proportions and the presence of dorsal warts and dermal ridges. Discovery of this new species indicates that the biodiversity of amphibians in this region remains underestimated. 展开更多
关键词 PHYLOGENY Mitochondrial DNA 16SrRNA Chiang Mai Province Cryptic species Fejervarya chiangmaiensis sp. nov.
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A new genus and three new species of miniaturized microhylid frogs from Indochina (Amphibia: Anura: Microhylidae: Asterophryinae) 被引量:2
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作者 Nikolay A. Poyarkov Chatmongkon Suwannapoom +4 位作者 Parinya Pawangkhanant Akrachai Aksornneam Tang Van Duong Dmitriy V. Korost Jing Che 《Zoological Research》 SCIE CAS CSCD 2018年第3期130-157,共28页
We report on the discovery of a new genus of microhylid subfamily Asterophryinae from northern and eastern Indochina, containing three new species. Vietnamophryne (3en. nov. are secretive miniaturized frogs (SVL〈21... We report on the discovery of a new genus of microhylid subfamily Asterophryinae from northern and eastern Indochina, containing three new species. Vietnamophryne (3en. nov. are secretive miniaturized frogs (SVL〈21 mm) with a mostly semi-fossorial lifestyle. To assess phylogenetic relationships, we studied 12S rRNA - 16S rRNA mtDNA fragments with a final alignment of 2 591 bp for 53 microhylid species. Morphological and osteological characters were analyzed using micro-CT scanning and used to describe the new genus. Results of phylogenetic analyses assigned the new genus into the mainly Australasian subfamily Asterophryinae as a sister taxon to the genus Siamophryne from southern Indochina. The three specimens collected from Gia Lai Province in central Vietnam, Cao Bang Province in northern Vietnam, and Chiang Rai Province in northern Thailand proved to be separate species, different both in morphology and genetics (genetic divergence 3.1%〈P〈5.1%). Our work provides further evidence for the "out of Indo-Eurasia" scenario for Asterophryinae, indicating that the initial cladogenesis and differentiation of this group of frogs occurred in the Indochina Peninsula. To date, eachof the three new species of Vietnamophryne Gen. nov. is known only from a single specimen; thus, their distribution, life history, and conservation status require further study. 展开更多
关键词 Vietnamophryne Gen.nov. Vietnamophryneinexpectata sp. nov. Vietnamophryne orlovisp. nov. Vietnamophryne occidentalis sp.nov. Siamophryne Gastrophrynoides mtDNA micro-CT scanning Vietnam Thailand HERPETOFAUNA AMPHIBIA Biogeography Taxonomy INDOCHINA
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A new species of smooth skink (Squamata: Scincidae: Scincella) from Cambodia 被引量:1
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作者 Thy Neang Somaly Chan Nikolay A. Poyarkov, Jr. 《Zoological Research》 SCIE CAS CSCD 2018年第3期220-240,共21页
Based on morphological and genetic evidence we evaluated the taxonomic status of a newly discovered forest-dwelling population of skink (genus Scincella) from the Keo Selma Wildlife Sanctuary, Mondulkiri Province, C... Based on morphological and genetic evidence we evaluated the taxonomic status of a newly discovered forest-dwelling population of skink (genus Scincella) from the Keo Selma Wildlife Sanctuary, Mondulkiri Province, Cambodia. From phylogenetic analysis of a 668-bp fragment of the mtDNA COl and diagnostic morphological characters we allocate the newly discovered population to the Scincella reevesii-S. rufocaudata species complex and describe it as Scincella nigrofasciata sp. nov. The new skink species can be distinguished from all other Southeast Asian congeners by the following combination of morphological characters: snout-vent length (SVL) 40.0-52.6 mm; relative tail length (TaL/SVL ratio) 1.25-1.94; prefrontals in broad contact; infralabials 6; primary temporals 2; relative forelimb length (FIL/SVL ratio) 0.20-0.22; relative hindlimb length (HIL/SVL ratio) 0.30-0.33; relative forearm length (FoL/SVL ratio) 0.14-0.16; adpressed forelimbs and hind limbs either overlapping (0.4-2.2 mm) or separated (1.9-2.3 mm); midbody scale rows 32-33, paravertebral scales 69-74, vertebral scales 65-69; dorsal scales between dorsolateral stripes 8; comparatively slender fingers and toes, subdigital lamellae under fourth toe 15-17; dark discontinuous regular dorsal stripes 5-7; distinct black dorsolateral stripes, narrowing to lateral sides and extending to 52%-86% of total tail length. We provide additional information on the holotype of Scincella rufocaudata (Darevsky & Nguyen, 1983), and provide evidence for the species status of Scincella rupicola. Our discovery brings the number of Scincellaspecies in Cambodia to five and emphasizes the incompleteness of knowledge on the herpetofaunal diversity of this country. 展开更多
关键词 Mondulkiri Keo Seima WildlifeSanctuary Taxonomy mtDNA COl DNA barcoding PHYLOGENETICS
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Soil salinity prediction in the Lower Cheliff plain(Algeria) based on remote sensing and topographic feature analysis 被引量:9
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作者 Ibrahim YAHIAOUI Abdelkader DOUAOUI +1 位作者 ZHANG Qiang Ahmed ZIANE 《Journal of Arid Land》 SCIE CSCD 2015年第6期794-805,共12页
Soil salinity and ground surface morphology in the Lower Cheliff plain(Algeria) can directly or indirectly impact the stability of environments. Soil salinization in this area is a major pedological problem related ... Soil salinity and ground surface morphology in the Lower Cheliff plain(Algeria) can directly or indirectly impact the stability of environments. Soil salinization in this area is a major pedological problem related to several natural factors, and the topography appears to be important in understanding the spatial distribution of soil salinity. In this study, we analyzed the relationship between topographic parameters and soil salinity, giving their role in understanding and estimating the spatial distribution of soil salinity in the Lower Cheliff plain. Two satellite images of Landsat 7 in winter and summer 2013 with reflectance values and the digital elevation model(DEM) were used. We derived the elevation and slope gradient values from the DEM corresponding to the sampling points in the field. We also calculated the vegetation and soil indices(i.e. NDVI(normalized difference vegetation index), RVI(ratio vegetation index), BI(brightness index) and CI(color index)) and soil salinity indices, and analyzed the correlations of soil salinity with topography parameters and the vegetation and soil indices. The results showed that soil salinity had no correlation with slope gradient, while it was significantly correlated with elevation when the EC(electrical conductivity) values were less than 8 d S/m. Also, a good relationship between the spectral bands and measured soil EC was found, leading us to define a new salinity index, i.e. soil adjusted salinity index(SASI). SASI showed a significant correlation with elevation and measured soil EC values. Finally, we developed a multiple linear regression for soil salinity prediction based on elevation and SASI. With the prediction power of 45%, this model is the first one developed for the study area for soil salinity prediction by the combination of remote sensing and topographic feature analysis. 展开更多
关键词 Landsat ETM+ morphology sampling salinity prediction Lower Cheliff plain
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A new species of the genus Theloderma Tschudi, 1838 (Amphibia: Anura: Rhacophoridae) from Tay Nguyen Plateau, central Vietnam 被引量:1
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作者 Nikolay A. Poyarkov Ivan I. Kropachev +1 位作者 Svetlana S. Gogoleva Nikolai L. Orlov 《Zoological Research》 SCIE CAS CSCD 2018年第3期158-184,共27页
A new species of small tree frog from a primary montane tropical forest of central Vietnam, Tay Nguyen Plateau, is described based on morphological, molecular, and acoustic evidence. The Golden Bug-Eyed Frog, Theloder... A new species of small tree frog from a primary montane tropical forest of central Vietnam, Tay Nguyen Plateau, is described based on morphological, molecular, and acoustic evidence. The Golden Bug-Eyed Frog, Theloderma auratum sp. nov., is distinguishable from its congeners and other small rhacophorid species based on a combination of the following morphological attributes: (1) bony ridges on head absent; (2) smooth skin completely lacking calcified warts or asperities; (3) pointed elongated tapering snout; (4) vocal opening in males absent; (5) vomerine teeth absent; (6) males of small body size (SVL 21.8-26.4 mm); (7) head longer than wide; ED/SVL ratio 13%-15%; ESL/SVL ratio 16%-20%; (8) small tympanum (TD/EL ratio 50%-60%) with few tiny tubercles; (9) supratympanic fold absent; (10) ventral surfaces completely smooth; (11 ) webbing between fingers absent; (12) outer and inner metacarpal tubercles present, supernumerary metacarpal tubercle single, medial, oval in shape; (13) toes half-webbed: I 2-21/4 II 11/^-23/~ III 2-31/4 IV 3-11/2 V; (14) inner metatarsal tubercle present, oval; outer metatarsal tubercle absent; (15) iris bicolored; (16) dorsal surfaces golden-yellow with sparse golden-orange speckling or reticulations and few small dark-brown spots; (17) lateral sides of head and body with wide dark reddish-brown to black lateral stripes, clearlyseparated from lighter dorsal coloration by straight contrasting edge; (18) ventral surfaces of body, throat, and chest greyish-blue with indistinct brown confluent blotches; (19) upper eyelids with few (3-5) very small flat reddish superciliary tubercles; (20) limbs dorsally reddish-brown, ventrally brown with small bluish-white speckles. The new species is also distinct from all congeners in 12S rRNA to 16S rRNA mitochondrial DNA fragment sequences (uncorrected genetic distance P〉8.9%). Advertisement call and tadpole morphology of the new species are described. Our molecular data showed Theloderma auratum sp. nov. to be a sister species of Th. palliatum from Langbian Plateau in southern Vietnam. 展开更多
关键词 Theloderma auratum sp. nov. mtDNAphylogeny 12S rRNA 16S rRNA Kon Tum Gia Lai ENDEMISM Taxonomy
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Stabilization versus decomposition in alpine ecosystems of the Northwestern Caucasus:The results of a tea bag burial experiment 被引量:1
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作者 Tatiana G.ELUMEEVA Vladimir G.ONIPCHENKO +2 位作者 Asem A.AKHMETZHANOVA Mikhail I.MAKAROV Joost A.KEUSKAMP 《Journal of Mountain Science》 SCIE CSCD 2018年第8期1633-1641,共9页
Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the l... Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the local carbon cycle: litter decomposition and carbon stabilization. In order to adequately reflect local heterogeneity, we have sampled 12 typical plant communities of the Russian Caucasus. In order to minimize confounding effects and encourage comparative studies, we have adapted the widely used tea bag index(TBI) that is typically used in areas with low decomposition. By incubating standardized tea litter for a year, we investigated whether(1) initial litter decomposition rate(k) is negatively correlated with litter stabilization(S) and(2) whether k or S exhibit correlations with altitude and other environmental conditions. Our results show that S and k are not correlated. Altitude, p H, and water content significantly influenced the stabilization factor S, while soil-freezing had no influence. In contrast, none of these factors predicted the decomposition rate k. Based on our data, we argue that collection of decomposition rates alone, as is now common practice, is not sufficient to understand carbon input to soils and can potentially lead to misleading results. Our data on community-specific decomposition and stabilization rates further constrain estimates of litter accumulation in subalpine communities and the potential effects of climate change. 展开更多
关键词 Litter decomposition Alpine communities Tea bag index Carbon cycle
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On the road to Mandalay: contribution to the Microhyla Tschudi, 1838(Amphibia: Anura: Microhylidae) fauna of Myanmar with description of two new species 被引量:1
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作者 Nikolay A. Poyarkov, Jr Vladislav A. Gorin +4 位作者 Than Zaw Valentina D. Kretova Svetlana S. Gogoleva Parinya Pawangkhanant Jing Che 《Zoological Research》 SCIE CAS CSCD 2019年第4期244-276,共33页
We prese nt a morphological and molecular assessment of the Microhyla fauna of Myanmar based on new collections from central (Magway Division) and northem (Kachin State) parts of the country. In total, six species of ... We prese nt a morphological and molecular assessment of the Microhyla fauna of Myanmar based on new collections from central (Magway Division) and northem (Kachin State) parts of the country. In total, six species of Microhyla are documented, including M. berdmorei, M. heymonsi, M. butleri, M. mukhlesuri and two new species described from the semi-arid savarma-like plains of the middle part of the Irrawaddy (Ayeyarwady) River Valley. We used a 2 481 bp long 12S rRNA- 16S rRNA fragment of mtDNA to hypothesize gen ealogical relati on ships within Microhyla. We applied an in teg rati ve taxonomic approach combining molecular, morphological, and acoustic lines of evidenee to evaluate the taxonomic status of Mya nmar Microhyla. We dem on strated that the newly discovered populations of Microhyla sp. from the Magway Division represent two yet undescribed species. These two new sympatric species are assigned to the M. achatina species group, with both adapted to the seas on ally dry environments of the Irrawaddy Valley. Microhyla fodiens sp. nov. is a stout-bodied species with a remarkably enlarged shovel-like outer metatarsal tubercle used for burrowing and is highly diverge nt from other know n congeners (P-distancea8.8%). Microhyla irrawaddy sp. nov. is a small-bodied slender frog reconstructed as a sister species to M. kodial from southern India (P-distance=5.3%);however, it clearly differs from the latter both in external morphology and advertisement call parameters. Microhyla mukhlesuri is reported from Myanmar for the first time. We further discuss the morphological diag no sties and biogeography of Microhyla species recorded in Myanmar. 展开更多
关键词 Narrow-mouth FROGS BURMA INDOCHINA Magway Kachin Biodiversity Taxonomy mtDNA Morphology Acoustics Advertisement call
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The characteristic pattern of multiple colored layers in coastal stratified lakes in the process of separation from the White Sea 被引量:1
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作者 Elena D.KRASNOVA Dmitry N.MATORIN +7 位作者 Tatiana A.BELEVICH Ludmila E.EFIMOVA Anastasiia V.KHARCHEVA Natalia M.KOKRYATSKAYA Galina N.LOSYUK Daria A.TODORENKO Dmitry A.VORONOV Svetlana V.PATSAEVA 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第6期1962-1977,共16页
An unusual feature of the saline stratified lakes that were formed due to ongoing postglacial uplift on the White Sea coast is the presence of several differently colored thin layers in the zone with sharp gradients. ... An unusual feature of the saline stratified lakes that were formed due to ongoing postglacial uplift on the White Sea coast is the presence of several differently colored thin layers in the zone with sharp gradients. Colored layers in five lakes at various stages of separation from the sea were investigated using optical microscopy, spectrophotometry, spectrofluorimetry, and photobiology. The upper greenish colored layer located in the aerobic strata of all lakes near the compensation depth of 1% light penetration contains green algae. In the chemocline, another layer, brightly green, red or pink, is dominated by mixotrophic flagellates. Despite the very low light intensities and the presence of H 2 S, active photosynthesis by these algae appears to be occurring, as indicated by high values of the maximum quantum yield of primary photochemistry, electron transport activity, photosynthetic activity of photosystem II, the fraction of active centers, and low values of heat dissipation. In the reduced zone of the chemocline, a dense green or brown suspension of anoxygenic phototrophs(green sulfur bacteria) is located. 展开更多
关键词 ALGAL BLOOMS COASTAL LAKES CHEMOCLINE fluorescence kinetics Arctic White Sea
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