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Spring migration duration exceeds that of autumn migration in Far East Asian Greater White-fronted Geese (Anser albifrons) 被引量:11
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作者 xueqin Deng Qingshan Zhao +5 位作者 Lei Fang zhenggang xu Xin Wang Haoren He Lei Cao Anthony David Fox 《Avian Research》 CSCD 2019年第3期319-329,共11页
Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimizati... Background:Migration theory suggests,and some empirical studies show, that in order to compete for the best breeding sites and increase reproductive success,long-distance avian migrants tend to adopt a time minimization strategy during spring migration, resulting in shorter duration spring migration compared to that in autumn.Methods:Using GPS/GSM transmitters,we tracked the full migrations of 11 Greater White-fronted Geese (Anser albifrons) between southeast China and the Russian Arctic,to reveal the migration timing and routes of the East Asian population, and compare the difference in duration between spring and autumn migration of this population.Results:We found that migration in spring (79 ± 12 days) took more than twice as long to cover the same distance as in autumn (35 ±7 days).This difference in migration duration was mainly determined by significantly more time spent in spring (59±16 days) than in autumn (23± 6days) at significantly more stopover sites. Conclusions:We suggest that these geese, thought to be partial capital breeders, spent almost three quarters of total migration time at spring stopover sites to acquire energy stores for ultimate investment in reproduction, although we cannot reject the hypothesis that timing of the spring thaw also contributed to stopover duration.In autumn,they acquired necessary energy stores on the breeding grounds sufficient to reach Northeast China staging areas almost without stop, which reduced stopover times in autumn and resulted in the faster autumn migration than spring. 展开更多
关键词 GREATER White-fronted Goose GPS/GSM tracking Migration Spring staging STOPOVER DURATION
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Ecological Security Evaluation Algorithm for Resource-Exhausted Cities Based on the PSR Model 被引量:4
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作者 Xiaozhou Li zhenggang xu +3 位作者 Yuanyuan Fu Qi Jin Yunlin Zhao Neal NXiong 《Computers, Materials & Continua》 SCIE EI 2021年第10期985-1001,共17页
Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of... Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of resource-exhausted cities.Using 23 indicators,this study evaluated the ecological security status and development trends of 21 resource-exhausted cities in China from 2011 to 2017.The results showed that from 2011 to 2015,the overall ecological security of this type of city was low,with over 60%of the cities at an unsafe level.However,ecological security improved rapidly after 2016,and by 2017,all of the cities had reached the critical safety level.The top 10 indicators of ecological security included industrial sulfur dioxide emissions,water supply,agricultural fertilizer application,and forest coverage.These 10 indicators’cumulative contribution to ecological security was 48.3%;among them,reducing industrial sulfur dioxide emissions contributed the most at 5.7%.These findings can help governments better understand the ecological security status of resource-exhausted cities,and it can provide a reference for the allocation of funds and other resources to improve the ecological safety of these cities. 展开更多
关键词 Ecological security PSR model EVALUATION resource-exhausted cities
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Contrasting habitat use and conservation status of Chinese-wintering and other Eurasian Greater White-fronted Goose(Anser albifrons)populations 被引量:1
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作者 xueqin Deng Qingshan Zhao +7 位作者 Junjian Zhang Andrea Kölzsch Diana Solovyeva Inga Bysykatova-Harmey zhenggang xu Helmut Kruckenberg Lei Cao Anthony David Fox 《Avian Research》 SCIE CSCD 2021年第4期600-611,共12页
Background:GPS/GSM tracking data were used to contrast use of(i)habitats and(ii)protected areas between three Arctic-nesting Greater White-fronted Geese(Anser albifrons,GWFG)populations throughout the annual cycle.We ... Background:GPS/GSM tracking data were used to contrast use of(i)habitats and(ii)protected areas between three Arctic-nesting Greater White-fronted Geese(Anser albifrons,GWFG)populations throughout the annual cycle.We wished to demonstrate that the East Asian Continental Population(which winters on natural wetlands in the Chinese Yangtze River floodplain and is currently declining)avoids using farmland at multiple wintering sites.We also gath-ered tracking evidence to support general observations from two increasing population of GWFG,the North Sea-Baltic(which winters in Europe)and the West Pacific(which winter in Korea and Japan)winter mostly within farmland landscapes,using wetlands only for safe night roosts.Methods:We tracked 156 GWFG throughout their annual cycle using GPS/GSM transmitters from these three popu-lations to determine migration routes and stopover staging patterns.We used Brownian Bridge Movement Models to generate summer,winter and migration stopover home ranges which we then overlaid in GIS with land cover and protected area boundary at national level to determine habitat use and degree of protection from nature conserva-tion designated areas.Results:Data confirmed that 73%of European wintering GWFG homes ranges were from within farmland,com-pared to 59%in Japan and Korea,but just 5%in China,confirming the heavy winter use of agricultural landscapes by GWFG away from China,and avoidance of farmland at multiple sites within the Yangtze River floodplain.The same GWFG used farmland in northeast China in spring and autumn,confirming their experience of exploiting such habi-tats at other stages of their annual cycle.Chinese wintering birds showed the greatest overlap with protected areas of all three populations,showing current levels of site safeguard are failing to protect this population.Conclusions:Results confirm the need for strategic planning to protect the East Asian Continental GWFG popu-lation.While the site protection network in place to protect the species seems adequate,it has failed to stop the declines.Buffalo grazing could serve as one simple strategy to improve the condition of feeding habitats at Dongting Lake and Poyang Lake in the Yangtze,where vast Carex meadows exist.In addition,while we warn against pushing GWFG to winter farmland feeding in China because of the long-term potential to conflict with agricultural interests,we recommend experimental sacrificial,disturbance-free farmland within designated refuge areas adjacent to the Yangtze River floodplain wetland reserves as a manipulative experiment to improve the conservation status of this population in years when natural food sources are limited. 展开更多
关键词 Farmland feeding Habitat use Migration National nature reserve Protected areas Staging areas
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The chloroplast genome comparative characteristic of artificial breeding tree,a case about Broussonetia kazinoki×Broussonetia papyrifera 被引量:1
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作者 WAN ZHANG GUIYAN YANG +3 位作者 YUNLIN ZHAO zhenggang xu HUANG HUIMIN JIAKANG ZHOU 《BIOCELL》 SCIE 2022年第3期803-819,共17页
Broussonetia kazinoki×Broussonetia papyrifera(ZJGS)is a hybrid species in Moraceae family,which has a very complicated hybrid origin.The excellent characteristics of fast growth,strong soil and water conservation... Broussonetia kazinoki×Broussonetia papyrifera(ZJGS)is a hybrid species in Moraceae family,which has a very complicated hybrid origin.The excellent characteristics of fast growth,strong soil and water conservation ability,high leaf protein content and stem fiber content in ZJGS make it both ecological benefits in the mining area and economically valuable.This study aims to further understand ZJGS and other Moraceae taxa through the ZJGS chloroplast(cp)genome structure and the comparison with 12 closely related Moraceae species.Among the 13 Moraceae species,the cp genome length of seven Broussonetia species(ranges from 160,239 bp to 162,594 bp)is larger than that of six Morus species(ranges from 158,459 bp to 159,265 bp).Among the 77 shared protein-coding genes(PCGs)in Moraceae species,the obvious positive selection of Ka/Ks ratios acted on petD and rpl16 genes of B.kazinoki and B.papyrifera,respectively.Phylogenetic analysis based on shared PCGs from 28 species shows that ZJGS is closely related to maternal B.kazinoki.These findings provide data support for the origin of ZJGS hybridization and provide genomic resources for future ZJGS resource development and molecular breeding. 展开更多
关键词 Broussonetia kazinoki Broussonetia papyrifera MORACEAE Phylogenetic relationship Maternal inheritance
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Insight into the characteristics of an important evolutionary model bird(Geospiza magnirostris)mitochondrial genome through comparison
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作者 zhenggang xu LIANG WU +4 位作者 JIAHAO CHEN YUNLIN ZHAO CHONGxuAN HAN TIAN HUANG GUIYAN YANG 《BIOCELL》 SCIE 2022年第7期1733-1746,共14页
Darwin’s finches are the most classic case of evolution.Early studies on the evolution of this species were mainly based on morphology.Until now,the mitochondrial genome of Geospiza magnirostris has been sequenced an... Darwin’s finches are the most classic case of evolution.Early studies on the evolution of this species were mainly based on morphology.Until now,the mitochondrial genome of Geospiza magnirostris has been sequenced and the study explored the characteristics of the complete genome of G.magnirostris and verified the evolutionary position of it.The 13 PCGs initiated by ATN codons.The stop codons of three PCGs(ND2,COX3 and ND4)were incomplete,with only T-or TA-replacing complete form TAA or TAG.All the tRNA genes expressed a typical cloverleaf secondary structure,except for tRNA^(Ser1)(AGY),whose dihydrouridine(DHU)arm was lack and instead with a simple loop.In the sequence of the control region of G.magnirostris,we found six simple repeat tandem sequences with a total length of 42 bp.Two characteristic conserved overlapping junction(ATGCTAA)and(CAAGAAAG)were observed as reported for eight selected Passeriformes birds.A special conserved overlapping junction(ATCTTACC)involved in mitochondrial transcription termination was found between tRNA^(Tyr) and COX1 in G.magnirostris’s control region.Four most frequently used amino acids in G.magnirostris’s PCGs were Leu1(CUN),Ile,Thr,Ala.The codon usage of G.magnirostris was relatively average,and there was no particular bias.The ratio Ka/Ks results showed that G.magnirostris receives less natural selection pressure.The phylogenetic relationships and cluster analysis of relative codon usage showed that G.magnirostris and Thraupis episcopus clustered in one branch.The phylogenetic position of G.magnirostris was consistent with the traditional taxonomic of Thraupis.The results supported the conclusion that G.magnirostris belongs to the morphological classification of the family Thraupidae. 展开更多
关键词 Geospiza magnirostris Mitochondrial genome Comparative analysis Evolution analysis Phylogenetic relationships
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RP11-40C6.2 Inactivates Hippo Signaling by Attenuating YAP1 Ubiquitylation in Hepatitis B Virus-associated Hepatocellular Carcinoma 被引量:3
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作者 Han Zhuo Chen Wu +5 位作者 Junwei Tang Feihong Zhang zhenggang xu Dongwei Sun Yue Teng Zhongming Tan 《Journal of Clinical and Translational Hepatology》 SCIE 2023年第2期323-333,共11页
Background and Aims:Chronic hepatitis caused by hepatitis B virus(HBV)infection is a leading cause of hepatocellular carcinoma(HCC).We investigated the roles of oncogenic HBV infection-associated long noncoding RNAs i... Background and Aims:Chronic hepatitis caused by hepatitis B virus(HBV)infection is a leading cause of hepatocellular carcinoma(HCC).We investigated the roles of oncogenic HBV infection-associated long noncoding RNAs in HCC.Methods:Bioinformatics analysis of data from the Cancer Genome Atlas(TCGA)was performed to screen potential oncogenic HBV-related lncRNAs.Next,we assessed their expression in clinical samples and investigated their correlation with clinical characteristics.The detailed oncogenic effects were analyzed by performing in vitro and in vivo studies.Results:RP11-40C6.2,an HBV infection-related lncRNA,was identified by analysis of the TCGA–Liver Hepatocellular Carcinoma database.Gene Set Enrichment Analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis of differentially expressed genes revealed a strong association of RP11-40C6.2 with the Hippo signaling pathway.RP11-40C6.2 was overexpressed in HCC patients with HBV infection compared to those without HBV infection.RP11-40C6.2 transcription showed a positive association with HBV-X protein(HBx),but not HBV core protein(HBc)expression,both of which are carcinogenic proteins.Luciferase gene reporter and ChIP assays revealed that YAP1/TAZ/TEADs complex enhanced RP11-40C6.2 transcription by binding to its promoter area.RP11-40C6.2 showed oncogenic characteristics in HCC cell lines and in animal models that were mediated via activation of YAP1.In vitro ubiquitylation assay revealed that RP11-40C6.2 can promote the stabilization of YAP1 by stopping phosphorylation at its s127 residue and further stopping its degradation through binding to 14-3-3.Conclusions:RP11-40C6.2 is an HBV infection-related lncRNA that exerts its oncogenic effects by targeting the Hippo signaling pathway. 展开更多
关键词 Hepatocellular carcinoma Hippo signaling lncRNA YAP1 HBV
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Annual migratory patterns of Far East Greylag Geese(Anser anser rubrirostris)revealed by GPS tracking 被引量:4
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作者 Xianghuang LI Xin WANG +7 位作者 Lei FANG Nyambayar BATBAYAR Tseveenmyadag NATSAGDORJ Batmunkh DAVAASUREN Iderbat DAMBA zhenggang xu Lei CAO Anthony David FOX 《Integrative Zoology》 SCIE CSCD 2020年第3期213-223,共11页
Twenty Far East Greylag Geese,Anser anser rubrirostris,were captured and fitted with Global Positioning System/Global System for Mobile Communications(GPS/GSM)loggers to identify breeding and wintering areas,migration... Twenty Far East Greylag Geese,Anser anser rubrirostris,were captured and fitted with Global Positioning System/Global System for Mobile Communications(GPS/GSM)loggers to identify breeding and wintering areas,migration routes and stopover sites.Telemetry data for the first time showed linkages between their Yangtze River wintering areas,stopover sites in northeastern China,and breeding/molting grounds in eastern Mongolia and northeast China.10 of the 20 tagged individuals provided sufficient data.They stopped on migration at the Yellow River Estuary,Beidagang Reservoir and Xar Moron River,confirming these areas as being important stopover sites for this population.The median spring migration duration was 33.7 days(individuals started migrating between 25 February and 16 March and completed migrating from 1 to 9 April)compared to 52.7 days in autumn(26 September-13 October until 4 November-11 December).The median stopover duration was 31.1 and 51.3 days and the median speed of travel was 62.6 and 47.9 km/day for spring and autumn migration,respectively.The significant differences between spring and autumn migration on the migration duration,the stopover duration and the migration speed confirmed that tagged adult Greylag Geese traveled faster in spring than autumn,supporting the hypothesis that they should be more time-limited during spring migration. 展开更多
关键词 Anser anser autumn migration greylag goose GPS/GSM loggers spring migration
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Habitat evaluation for outbreak of Yangtze voles(Microtus fortis)and management implications
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作者 zhenggang xu Yunlin ZHAO +3 位作者 Bo LI Meiwen ZHANG Guo SHEN Yong WANG 《Integrative Zoology》 SCIE CSCD 2015年第3期267-281,共15页
Rodent pests severely damage agricultural crops.Outbreak risk models of rodent pests often do not include sufficient information regarding geographic variation.Habitat plays an important role in rodent-pest outbreak r... Rodent pests severely damage agricultural crops.Outbreak risk models of rodent pests often do not include sufficient information regarding geographic variation.Habitat plays an important role in rodent-pest outbreak risk,and more information about the relationship between habitat and crop protection is urgently needed.The goal of the present study was to provide an outbreak risk map for the Dongting Lake region and to understand the relationship between rodent-pest outbreak variation and habitat distribution.The main rodent pests in the Dongting Lake region are Yangtze voles(Microtus fortis).These pests cause massive damage in outbreak years,most notably in 2007.Habitat evaluation and ecological details were obtained by analyzing the correlation between habitat suitability and outbreak risk,as indicated by population density and historical events.For the source-sink population,96.18%of Yangtze vole disaster regions were covered by a 10-km buffer zone of suitable habitat in 2007.Historical outbreak frequency and peak population density were significantly correlated with the proportion of land covered by suitable habitat(r=0.68,P=0.04 and r=0.76,P=0.03,respectively).The Yangtze vole population tends to migrate approximately 10 km in outbreak years.Here,we propose a practical method for habitat evaluation that can be used to create integrated pest management plans for rodent pests when combined with basic information on the biology,ecology and behavior of the target species. 展开更多
关键词 geographical information systems habitat evaluation remote sensing rodent pest management Yangtze vole
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