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1.
Zool Res ; 43(5): 787-804, 2022 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-35993131

RESUMO

The Paramesotriton Chang, 1935 genus of Asian warty newts is the second most diverse genus in the family Salamandridae, currently containing 14 recognized species from northern Vietnam to southwest-central and southern China. Although species of this genus have been included in previous phylogenetic studies, the origin and interspecific relationships of the genus are still not fully resolved, especially at key nodes in the phylogeny. In this study, we sequenced mitochondrial genomes and 32 nuclear genes from 27 samples belonging to 14 species to reconstruct the interspecific phylogenetic relationships within Paramesotriton and explore its historical biogeography in southern China. Both Bayesian inference and maximum-likelihood analyses highly supported the monophyly of Paramesotriton and its two recognized species groups ( P. caudopunctatus and P. chinensis groups) and further identified five hypothetical phylogenetic cryptic species. Biogeographic analyses indicated that Paramesotriton originated in southwestern China (Yunnan-Guizhou Plateau/South China) during the late Oligocene. The time of origin of Paramesotriton corresponded to the second uplift of the Himalayan/Qinghai-Xizang (Tibetan) Plateau (QTP), rapid lateral extrusion of Indochina, and formation of karst landscapes in southwestern China. Principal component analysis (PCA), independent sample t-tests, and niche differentiation using bioclimatic variables based on locations of occurrence suggested that Paramesotriton habitat conditions in the three current regions (West, South, and East) differ significantly, with different levels of climatic niche differentiation. Species distribution model (SDM) predictions indicated that the most suitable distribution areas for the P. caudopunctatus and P. chinensis species groups are western and southern/eastern areas of southern China. This study increases our knowledge of the taxonomy, biodiversity, origin, and suitable distribution areas of the genus Paramesotriton based on phylogenetic, biogeographic, and species distribution models.


Assuntos
Genoma Mitocondrial , Animais , Teorema de Bayes , China , Filogenia , Salamandridae/genética
2.
Mitochondrial DNA B Resour ; 7(4): 587-589, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402708

RESUMO

In this study, the complete mitochondrial genome of Ia io from Guizhou Province, China. The genome was a circular mitochondrial genome of 16689 bp in length, containing 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNA), 2 ribosomal RNA genes (rRNA), and a control region. The average base composition is 32.76% A, 24.59% C, 14.49% G, and 28.16% T. The first complete mitochondrial genome of I. io provides fundamental data for future systematic taxonomic studies of the genus Ia.

3.
J Zhejiang Univ Sci B ; 7(7): 532-41, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16773726

RESUMO

Vehicle emissions are a major source of air pollution in urban areas. The impact on urban air quality could be reduced if the trends of vehicle emissions are well understood. In the present study, the real-world emissions of vehicles were measured using a remote sensing system at five sites in Hangzhou, China from February 2004 to August 2005. More than 48000 valid gasoline powered vehicle emissions of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NO) were measured. The results show that petrol vehicle fleet in Hangzhou has considerably high CO emissions, with the average emission concentration of 2.71%+/-0.02%, while HC and NO emissions are relatively lower, with the average emission concentration of (153.72+/-1.16)x10(-6) and (233.53+/-1.80)x10(-6), respectively. Quintile analysis of both average emission concentration and total amount emissions by model year suggests that in-use emission differences between well maintained and badly maintained vehicles are larger than the age-dependent deterioration of emissions. In addition, relatively new high polluting vehicles are the greatest contributors to fleet emissions with, for example, 46.55% of carbon monoxide fleet emissions being produced by the top quintile high emitting vehicles from model years 2000-2004. Therefore, fleet emissions could be significantly reduced if new highly polluting vehicles were subject to effective emissions testing followed by appropriate remedial action.


Assuntos
Automóveis/estatística & dados numéricos , Monitoramento Ambiental/métodos , Hidrocarbonetos/análise , Óxido Nítrico/análise , Emissões de Veículos/análise , Monóxido de Carbono/análise , China , Cidades/estatística & dados numéricos
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