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Insights into genetic diversity and phenotypic variations in domestic geese through comprehensive population and pan-genome analysis 被引量:1
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作者 Guangliang Gao Hongmei Zhang +5 位作者 Jiangping Ni Xianzhi Zhao Keshan Zhang Jian Wang Xiangdong Kong Qigui Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期88-107,共20页
Background Domestic goose breeds are descended from either the Swan goose(Anser cygnoides)or the Greylag goose(Anser anser),exhibiting variations in body size,reproductive performance,egg production,feather color,and ... Background Domestic goose breeds are descended from either the Swan goose(Anser cygnoides)or the Greylag goose(Anser anser),exhibiting variations in body size,reproductive performance,egg production,feather color,and other phenotypic traits.Constructing a pan-genome facilitates a thorough identification of genetic variations,thereby deepening our comprehension of the molecular mechanisms underlying genetic diversity and phenotypic variability.Results To comprehensively facilitate population genomic and pan-genomic analyses in geese,we embarked on the task of 659 geese whole genome resequencing data and compiling a database of 155 RNA-seq samples.By constructing the pan-genome for geese,we generated non-reference contigs totaling 612 Mb,unveiling a collection of 2,813 novel genes and pinpointing 15,567 core genes,1,324 softcore genes,2,734 shell genes,and 878 cloud genes in goose genomes.Furthermore,we detected an 81.97 Mb genomic region showing signs of genome selection,encompassing the TGFBR2 gene correlated with variations in body weight among geese.Genome-wide association studies utilizing single nucleotide polymorphisms(SNPs)and presence-absence variation revealed significant genomic associations with various goose meat quality,reproductive,and body composition traits.For instance,a gene encoding the SVEP1 protein was linked to carcass oblique length,and a distinct gene-CDS haplotype of the SVEP1 gene exhibited an association with carcass oblique length.Notably,the pan-genome analysis revealed enrichment of variable genes in the“hair follicle maturation”Gene Ontology term,potentially linked to the selection of feather-related traits in geese.A gene presence-absence variation analysis suggested a reduced frequency of genes associated with“regulation of heart contraction”in domesticated geese compared to their wild counterparts.Our study provided novel insights into gene expression features and functions by integrating gene expression patterns across multiple organs and tissues in geese and analyzing population variation.Conclusion This accomplishment originates from the discernment of a multitude of selection signals and candidate genes associated with a wide array of traits,thereby markedly enhancing our understanding of the processes underlying domestication and breeding in geese.Moreover,assembling the pan-genome for geese has yielded a comprehensive apprehension of the goose genome,establishing it as an indispensable asset poised to offer innovative viewpoints and make substantial contributions to future geese breeding initiatives. 展开更多
关键词 Gene-CDS haplotype Goose GWAS PAN-GENOME Presence-absence variation Selection signal
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Variations in evaporation from water surfaces along the margins of the Badain Jaran Desert over nearly 60 years and influencing factors 被引量:1
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作者 Li-juan Wang Zhe Wang +3 位作者 Gao-lei Jiang Zhen-long Nie Jian-mei Shen Sheng-hua Song 《Journal of Groundwater Science and Engineering》 2024年第3期253-263,共11页
Based on meteorological data collected over nearly 60 years(1960-2017)from four national meteorological stations along the margins of the Badain Jaran Desert,this study analyzed the spatiotemporal variations in evapor... Based on meteorological data collected over nearly 60 years(1960-2017)from four national meteorological stations along the margins of the Badain Jaran Desert,this study analyzed the spatiotemporal variations in evaporation from water surfaces and identified the dominant controlling factors.Methods used included linear trend analysis,linear tendency estimation,the departure method,the rank correlation coefficient-based method,and Multiple Linear Regression(MLR).Results indicate notable spatiotemporal differences in evaporation distribution and evolution.Spatially,average annual evaporation exhibited a pronounced altitude effect,decreasing at a rate of about 8.23 mm/m from east to west with increasing altitude.Temporally,annual evaporation showed significant upward trends after 1996 at the northeastern(Guaizi Lake)and western(Dingxin)margins,with rates of 132 mm/10a and 105 mm/10a,respectively.Conversely,along the northwestern(Ejina Banner)and southern(Alxa Right Banner)margins of the desert,an evaporation paradox was observed,with annual evaporation trending downward at rates of 162 mm/10a and 187 mm/10a,respectively,especially after 1987.The dominant factors controlling evaporation varied spatially:Average annual temperature and relative humidity influended the western margin(Dingxin),average annual temperature was the key factor for the northeastern margin(Guaizi Lake),and average wind speed was crucial for the northern(Ejina Banner)and southern(Alxa Right Banner)margins. 展开更多
关键词 Evaporation from water surface Evaporation paradox Dominant controlling factor Variation trend
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Associations of genome-wide structural variations with phenotypic differences in cross-bred Eurasian pigs
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作者 Wencheng Zong Jinbu Wang +8 位作者 Runze Zhao Naiqi Niu Yanfang Su Ziping Hu Xin Liu Xinhua Hou Ligang Wang Lixian Wang Longchao Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期68-87,共20页
Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability ... Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability to adapt to the local environment.SVs(≥50 bp)are widely distributed in the genome,mainly in the form of insertion(INS),mobile element insertion(MEI),deletion(DEL),duplication(DUP),inversion(INV),and translocation(TRA).While studies have investigated the SVs in pig genomes,genome-wide association studies(GWAS)-based on SVs have been rarely conducted.Results Here,we obtained a high-quality SV map containing 123,151 SVs from 15 Large White and 15 Min pigs through integrating the power of several SV tools,with 53.95%of the SVs being reported for the first time.These high-quality SVs were used to recover the population genetic structure,confirming the accuracy of genotyping.Potential functional SV loci were then identified based on positional effects and breed stratification.Finally,GWAS were performed for 36 traits by genotyping the screened potential causal loci in the F2 population according to their corresponding genomic positions.We identified a large number of loci involved in 8 carcass traits and 6 skeletal traits on chromosome 7,with FKBP5 containing the most significant SV locus for almost all traits.In addition,we found several significant loci in intramuscular fat,abdominal circumference,heart weight,and liver weight,etc.Conclusions We constructed a high-quality SV map using high-coverage sequencing data and then analyzed them by performing GWAS for 25 carcass traits,7 skeletal traits,and 4 meat quality traits to determine that SVs may affect body size between European and Chinese pig breeds. 展开更多
关键词 Body size GWAS PIG SKELETON Structural variations
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Model-based risk assessment on dynamic control of twin-column continuous capture under feedstock variations
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作者 Yu Fan Liang-Zhi Qiao +1 位作者 Shan-Jing Yao Dong-Qiang Lin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期22-30,共9页
Dynamic control is essential to guarantee the stable performance of continuous chromatography.AutoMAb dynamic control strategy has been developed to ensure a consistent protein load in twincolumn CaptureSMB continuous... Dynamic control is essential to guarantee the stable performance of continuous chromatography.AutoMAb dynamic control strategy has been developed to ensure a consistent protein load in twincolumn CaptureSMB continuous capture by integrating the UV signal of breakthrough.In this study,the process risk of CaptureSMB continuous capture under AutoMAb control towards the feedstock variations was assessed by a mechanistic model developed by us.The effects of target protein and impurities under the variation range of±10 mAU·min^(-1) on load amount,protein loss,process productivity,and resin capacity utilization were investigated.The results showed that the CaptureSMB process could be successfully controlled by AutoMAb towards increased or slightly decreased concentration of feedstock.However,the load process would be out of control with drastically decreased target protein or impurities,and the decreased impurities would lead to protein loss.It was found that AutoMAb control would cause 44.7%non-operational areas and 18.3%protein loss areas in the variation range of±10 mAU·min^(-1).To improve the stability of the CaptureSMB process,a modified AutoMAb control that would stop the load procedure when the absolute value of the integral area reached the preset value,was proposed to reduce the risk of protein loss and the non-operational area. 展开更多
关键词 Continuous chromatography Process control Feedstock variations Mechanistic modeling PURIFICATION
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Inter-annual variations of dissolved oxygen and hypoxia off the northern Changjiang River(Yangtze River) Estuary in summer from 1997 to 2014
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作者 Anqi Liu Feng Zhou +6 位作者 Xiao Ma Qiang Zhao Guanghong Liao Yuntao Zhou Di Tian Xiaobo Ni Ruibin Ding 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期119-130,共12页
Hypoxia off the Changjiang River Estuary has been the subject of much attention,yet systematic observations have been lacking,resulting in a lack of knowledge regarding its long-term change and drivers.By revisiting t... Hypoxia off the Changjiang River Estuary has been the subject of much attention,yet systematic observations have been lacking,resulting in a lack of knowledge regarding its long-term change and drivers.By revisiting the repeated surveys of dissolved oxygen(DO) and other relevant hydrographic parameters along the section from the Changjiang River Estuary to the Jeju-do in the summer from 1997 to 2014,rather different trends were revealed for the dual low-DO cores.The nearshore low-DO core,located close to the river mouth and relatively stable,shows that hypoxia has become more severe with the lowest DO descen ding at a rate of -0.07 mg/(L·a) and the thickness of low-DO zone rising at a rate of 0.43 m/a.The offshore core,centered around 40-m isobath but moving back and forth between 123.5°-125°E,shows large fluctuations in the minimum DO concentration,with the thickness of low-DO zone falling at a rate of -1.55 m/a.The probable factors affecting the minimum DO concentration in the two regions also vary.In the nearshore region,the decreasing minimum DO is driven by the increase in both stratification and primary productivity,with the enhanced extension of the Changjiang River Diluted Water(CDW) strengthening stratification.In the offshore region,the fluctuating trend of the minimum DO concentration indicates that both DO loss and DO supplement are distinct.The DO loss is primarily attributed to bottom apparent oxygen utilization caused by the organic matter decay and is also relevant to the advection of low-DO water from the nearshore region.The DO supplement is primarily due to weakened stratification.Our analysis also shows that the minimum DO concentration in the nearshore region was extremely low in 1998,2003,2007 and 2010,related to El Ni?o signal in these summers. 展开更多
关键词 dissolved oxygen low-DO Changjiang River Estuary interannual variations DUAL-CORE
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Spatiotemporal variations,influencing factors,and configurational promotion paths of energy efficiency in China’s cities
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作者 Ruyu Xu Keliang Wang +1 位作者 Zhuang Miao Lingxuan Sun 《Chinese Journal of Population,Resources and Environment》 2024年第1期74-86,共13页
The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration p... The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration promotion paths of EE in 284 Chinese cities during 2003‒2019 using the global super-efficiency minimum distance to strong efficient frontier(G-S-MinDS),exploratory spatial data analysis(ESDA),multiscale geographically weighted regression(MGWR),and fuzzy set qualitative comparative analysis(fsQCA)methods.The findings are:①China’s cities have an annual average EE of 0.658 with a growth rate of 0.53%,showing considerable promotion potential.②Industrial structure optimization,population agglomeration,economic development,and increased green coverage contribute positively,while government intervention and openness hinder China’s urban EE.③Four configurational promotion paths for enhancing China’s urban EE are identified,where among those paths population density is a core condition,while government intervention is not.This study provides valuable insights into substantially improving urban EE,emphasizing the need for targeted policies to address energy and environmental crises in China. 展开更多
关键词 Energy efficiency Spatiotemporal variations Influencing factors Configurational promotion paths
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High Prevalence of Anatomical Variations and Anomalies of the Coronary Arteries Detected by CT Angiography in Symptomatic Patients
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作者 Ghazi A.Alshumrani 《Congenital Heart Disease》 SCIE 2024年第2期197-206,共10页
Objective:Coronary artery anatomical variations and anomalies are an important topic due to their potential clinical manifestations.This study aims to investigate the prevalence of coronary artery anatomical variation... Objective:Coronary artery anatomical variations and anomalies are an important topic due to their potential clinical manifestations.This study aims to investigate the prevalence of coronary artery anatomical variations and anomalies in symptomatic patients with coronary computed tomography angiography(CCTA).Methods:This is a retrospective study that included all symptomatic patients who had CCTA in a tertiary care hospital in Saudi Arabia during a period of seven years.Results:The total number of included patients was 507(60%males)with a mean age of 57.4 years.Approximately 41%had luminal stenoses,averaging 49.7%.The total num-ber of patients with coronary anatomical variations(CAV)and coronary artery anomalies(CAA)was 217(43%).CAV prevalence was 26%,which included 14%non-right coronary dominance,5%short left main coronary artery(LMCA),and 7%division variations(trifurcation and quadrifurcarion)of the LMCA.The prevalence of CAA was 29%,which included 5%origin anomalies,22%myocardial bridge,and 2%course anomalies.Conclusions:A high prevalence of coronary artery anatomic variations and anomalies in symptomatic patients is reported in this study.Systematic reviews,meta-analyses,reporting guidelines,and unified definitions and classifications of cor-onary variations and anomalies are lacking in the literature,presenting potential opportunities for future research and publications. 展开更多
关键词 Coronary artery anomalies coronary anatomical variation coronary CT angiography
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Temporal and spatial variations hydrochemical components and driving factors in Baiyangdian Lake in the Northern Plain of China
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作者 Tian-lun Zhai Qian-qian Zhang +1 位作者 Long Wang Hui-wei Wang 《Journal of Groundwater Science and Engineering》 2024年第3期293-308,共16页
Understanding the temporal and spatial variation of hydrochemical components in large freshwater lakes is crucial for effective management and conversation.In this study,we identify the temporalspatial characteristics... Understanding the temporal and spatial variation of hydrochemical components in large freshwater lakes is crucial for effective management and conversation.In this study,we identify the temporalspatial characteristics and driving factors of the hydrochemical components in Baiyangdian Lake using geochemical methods(Gibbs diagram,Piper diagram and End-element diagram of ion ratio)and multivariate statistical techniques(Principal component analysis and Correlation analysis).16 sets of samples were collected from Baiyangdian Lake in May(normal season),July(flood season),and December(dry season)of 2022.Results indicate significant spatial variation in Nat,ci,SO and NO,,suggesting a strong influence of human activities.Cation concentrations exhibit greater seasonal variation in the dry season compared to the flood season,while the concentrations of the four anions show inconsistent seasonal changes due to the combined effects of river water chemical composition and human activities.The hydrochemical type of Baiyangdian Lake is primarily HCO,Cl-Na.Ca,Mg*and HCO,originate mainly from silicate and carbonate rock dissolution,while Kt,Nat and CI originate mainly from sewage and salt dissolution in sediments.SO42 may mainly stem from industrial wastewater,while NO,primarily originates from animal feces and domestic sewage.Through the use of Principal Component Analysis,it is identified that water-rock interaction(silicate and carbonate rocks dissolution,and dissolution of salt in sediments),carbonate sedimentation,sewage,agricultural fertilizer and manure,and nitrification are the main driving factors of the variation of hydrochemical components of Baiyangdian Lake across three hydrological seasons.These findings suggest the need for effective control of substandard domestic sewage discharge,optimization of agricultural fertilization strategies,and proper management of animal manure to comprehensively improve the water environment in Baiyangdian Lake. 展开更多
关键词 Hydrochemical variation SOURCES Human activities Water-rock interaction Multivariate statistical techniques
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Spatiotemporal variations of parameters of internal solitary waves in the northern South China Sea
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作者 Yu’ang LIU Yifei JIANG +3 位作者 Xiaojiang ZHANG Zhiyuan WANG Yu CAO Huizan WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期421-438,共18页
The dynamic parameters for internal solitary waves(ISWs)derived from the extended Korteweg-de Vries(eKdV)equation play an important role in the understanding and prediction of ISWs.The spatiotemporal variations of the... The dynamic parameters for internal solitary waves(ISWs)derived from the extended Korteweg-de Vries(eKdV)equation play an important role in the understanding and prediction of ISWs.The spatiotemporal variations of the dynamic parameters of the ISWs in the northern South China Sea(SCS)were studied based on the reanalysis of long-term temperature and salinity datasets.The results for spectrum analysis show that there are definite geographical differences for the periodic variation of the parameters:in shallow water,all parameters vary with a wave period of one year,while in deep water wave components of the parameters at other frequencies exist.Using wavelet analysis,the wavelet power spectral densities in deep water exhibited an inter-annual variation pattern.For example,the wave component of the dispersion coefficient with a wave period of about half a year reached its power peak once every two years.Based on previous work,this inter-annual variation pattern was deduced to be caused by dynamic processes.In further work on the regulatory mechanisms,empirical orthogonal function(EOF)decomposition was performed.It was found that the modes of the dispersion coefficient have different geographical distributions,explaining the reason why the wave components in different frequencies appeared in different locations.The numerical simulation results confirm that the variations in the parameters of the ISWs derived from the eKdV equation could affect the waveforms significantly because of changes in the polarity of the ISWs.Therefore,the periodic variations of the dynamic parameters are related to the geographical location because of dynamic processes operating. 展开更多
关键词 internal solitary waves(ISWs) dynamic parameters eKdV equation spatiotemporal variation polarity empirical orthogonal function(EOF)decomposition
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Relationship Between Gene-Phenotype and Clinical Manifestations of Chromosomal Copy Number Variations Indicated by Non-Invasive Prenatal Testing
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作者 Zixin Pi Xiaoyan Duan +1 位作者 Jing Peng Yanhui Liu 《Journal of Clinical and Nursing Research》 2024年第1期88-95,共8页
Objective:To analyze the clinical value of non-invasive prenatal testing(NIPT)in detecting chromosomal copy number variations(CNVs)and to explore the relationship between gene expression and clinical manifestations of... Objective:To analyze the clinical value of non-invasive prenatal testing(NIPT)in detecting chromosomal copy number variations(CNVs)and to explore the relationship between gene expression and clinical manifestations of chromosomal copy number variations.Methods:3551 naturally conceived singleton pregnant women who underwent NIPT were included in this study.The NIPT revealed abnormalities other than sex chromosome abnormalities and trisomy 13,18,and 21.Pregnant women with chromosome copy number variations underwent genetic counseling and prenatal ultrasound examination.Interventional prenatal diagnosis and chromosome microarray analysis(CMA)were performed.The clinical phenotypes and pregnancy outcomes of different prenatal diagnoses were analyzed.Additionally,a follow-up was conducted by telephone to track fetal development after birth,at six months,and one year post-birth.Results:A total of 53 cases among 3551 cases showed chromosomal copy number variation.Interventional prenatal diagnosis was performed in 36 cases:27 cases were negative and 8 were consistent with the NIPT test results.This indicates that NIPT’s positive predictive value(PPV)in CNVs is 22.22%.Conclusion:NIPT has certain clinical significance in screening chromosome copy number variations and is expected to become a routine screening for chromosomal microdeletions and microduplications.However,further interventional prenatal diagnosis is still needed to identify fetal CNVs. 展开更多
关键词 Non-invasive prenatal testing Chromosomal copy number variation Chromosomes 1 and 3 Chromosome 4 Chromosome 7 Chromosome 15 Prenatal diagnosis
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基于手机信令数据的广州市居民公园访问行为空间分异及其影响因素分析
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作者 刘晔 叶柏麟 吴景豪 《中山大学学报(自然科学版)(中英文)》 CAS 北大核心 2025年第1期195-206,共12页
加快推进城市公园建设是实现人与自然和谐共生的重要抓手。既有研究大多基于问卷调查数据和访谈资料分析城市居民的公园访问行为空间分异特征,研究结论的普适性和科学性有限。手机信令数据具有大样本、覆盖范围广、信息被动提供和动态... 加快推进城市公园建设是实现人与自然和谐共生的重要抓手。既有研究大多基于问卷调查数据和访谈资料分析城市居民的公园访问行为空间分异特征,研究结论的普适性和科学性有限。手机信令数据具有大样本、覆盖范围广、信息被动提供和动态实时性强等优点。利用手机信令数据精准刻画城市居民的公园访问行为,有助于开展城市公园的布局优化与品质提升工作。基于个体尺度的手机信令数据,本研究试图揭示广州市居民公园访问行为的空间分异特征并识别其影响因素,尤其关注城区居民和郊区居民的差别。结果表明:(1)城区居民的公园访问频率、公园访问时长和公园访问强度均高于郊区居民,前者的公园平均访问距离低于后者;(2)公园访问频率、公园访问强度、公园平均逗留时间和公园平均访问距离呈现高值集聚区/低值集聚区在城区连片分布,在郊区零星分布的空间特征;(3)公园访问行为受性别、年龄、时空约束性、社会经济地位、公园可达性、社区出行便利性和出行适宜性等因素的共同影响。本研究为相关政府部门精准开展城市公园的规划、建设与管理工作提供决策参考。 展开更多
关键词 城市公园 公园访问行为 空间分异 手机信令数据 广州
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Genetic variations of wood properties and growth characters of Ko-rean pines from different provenances 被引量:4
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作者 王慧梅 夏德安 +1 位作者 王文杰 杨书文 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期277-280,337,共4页
Totally 26 provenance stands of 17-year-old Korean pine were selected for investigating wood properties and growth characters in Mao抏rshan Experimental Forest Farm of Northeast Forestry University in 1999. The anatom... Totally 26 provenance stands of 17-year-old Korean pine were selected for investigating wood properties and growth characters in Mao抏rshan Experimental Forest Farm of Northeast Forestry University in 1999. The anatomical property indexes, including tracheid length, tracheid diameter and wall-indiameter ratio, and the physical property indexes, such as growth ring width, late wood percentage and growth ring density, were measured for wood properties. Growth character indexes, including tree height and diameter at breast height, were also measured. The analytical results showed that there exited obviously dif-ference in wood property indexes between different provenances, which is suggested that wood properties are controlled by their genetic differences. The growth character indexes of Korean pines presented significant difference and they might also be controlled by their genetic differences. Most parameters of wood properties mainly varied in the direction of longitude, but the parameters of growth characters varied in the direction of latitude. 展开更多
关键词 Korean pine Provenance trial Wood properties Geographical variation Genetic variation
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Variations of Melanocortin Receptor 1 (MC1R) Gene in Three Pig Breeds 被引量:8
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作者 顿桂玲 李祥龙 +2 位作者 曹洪战 周荣艳 李兰会 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第9期777-782,共6页
Variations of Melanocortin Receptor 1 (MC1R) were investigated using sequencing, PCR-RFLP and PCR-SSCP, in three pig breeds, Landrace, Yorkshire, and Duroc. Five polymorphic sites were found, in which 668G→C occurr... Variations of Melanocortin Receptor 1 (MC1R) were investigated using sequencing, PCR-RFLP and PCR-SSCP, in three pig breeds, Landrace, Yorkshire, and Duroc. Five polymorphic sites were found, in which 668G→C occurred within 5' UTR, nt894insCC in coding region resulting in a premature stop at codon 56, and 1318C→T, 1554G→A, l197G→A in coding region resulting in Ala164Val, Ala243Thr, and Asp124Asn respectively. All individuals in Landrace and Yorkshire present homozygous 668GG, 1197AA, 1318CC, and 1554GG, and have CC insertions at the 894 site, whereas the individuals in Duroc present a contrast homozygous 668CC, 1197GG, 1318TT, and 1554AA, and have no CC insertions at the corresponding site. No heterozygote has been found at these mutation sites. Presumably, 668G→C, 1318C→T, and 1554G→A may be associated with the recessive red color in the Duroc breed, and nt894insCC making 1197G→A nonsense may be associated with the white color in Landrace and Yorkshire breeds. 展开更多
关键词 PIG MC1R gene VARIATION coat color
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Stochastic Analysis of Interconnect Delay in the Presence of Process Variations 被引量:3
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作者 李鑫 Janet M.Wang +1 位作者 唐卫清 吴慧中 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第2期304-309,共6页
Process variations can reduce the accuracy in estimation of interconnect performance. This work presents a process variation based stochastic model and proposes an effective analytical method to estimate interconnect ... Process variations can reduce the accuracy in estimation of interconnect performance. This work presents a process variation based stochastic model and proposes an effective analytical method to estimate interconnect delay. The technique decouples the stochastic interconnect segments by an improved decoupling method. Combined with a polynomial chaos expression (PCE), this paper applies the stochastic Galerkin method (SGM) to analyze the system response. A finite representation of interconnect delay is then obtained with the complex approximation method and the bisection method. Results from the analysis match well with those from SPICE. Moreover, the method shows good computational efficiency, as the running time is much less than the SPICE simulation's. 展开更多
关键词 coupled interconnects process variations stochastic modeling delay estimation stochastic Galerkin method polynomial chaos expression
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Dissolved Inorganic Arsenic in the Yellow Sea and the East China Sea—Distributions and Seasonal Variations 被引量:2
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作者 任景玲 刘素美 张经 《Marine Science Bulletin》 CAS 2009年第1期24-36,共13页
The distributions and seasonal variations of total dissolved inorganic arsenic (TDIAs, [TDIAs] = [As^5+]+[As^3+]) and arsenite (As3.) in the Yellow Sea and East China Sea are presented hero based on the observa... The distributions and seasonal variations of total dissolved inorganic arsenic (TDIAs, [TDIAs] = [As^5+]+[As^3+]) and arsenite (As3.) in the Yellow Sea and East China Sea are presented hero based on the observations of 9 cruises carried out in 2000 - 2003. The study area covers a broad range of hydrographic and chemical properties. The emphasis is put on a southeast transect from Changjiang Estuary to the Ryukyu Islands (i.e. PN section) in the East China Sea to discuss the impact of terrestdal input on the marginal seas of China. Arsenic species (TDlAs and arsenite) are determined by selective hydride generation - atomic fluorescence spectrometry (HG-AFS). TDIAs concentrations were high in the coastal area of Changjiang Estuary and decreased slightly towards the shelf region. High concentratiOns of TDIAs were also existed in the near bottom layer of shelf edge of the East China Sea which indicated another source of arsenic from the incursion of Kuroshio Waters. The seasonal variations of TDIAs in the study area depend on the hydrographic stages of Changjiang and the incursion intensity of Kuroshio Waters. Arsenite showed opposite distributions with TDIAs, with higher concentrations appeared at the surface layer of shelf region, which was positive correlated with the chlorophyll a. Biological conversion of arsenate into arsenite was hypothesized for the observed distribution pattern and its seasonal variations. The stoichoimetric ratios of As to P were estimated to be about 2×10^3 at PN Section in summer. The concentrations of dissolved arsenic in the Yellow Sea and East China Sea were comparable with other areas in the world. 展开更多
关键词 dissolved arsenic SPECIES Yellow Sea and East China Sea distributions and seasonal variations
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Horizontal Distribution and Annual Variations of Fecal Coliform Bacteria in Luoyuan Bay 被引量:2
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作者 蔡雷鸣 《Marine Science Bulletin》 CAS 2010年第1期48-58,共11页
Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100... Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100 mL) to 540 cfu/100 mL in Luoyuan Bay. Values of FCB during August to October were significantly higher than those during January to April during three year period. Monthly changes of FCB values at each year period were mainly due to monthly precipitation. In addition, compared with FCB values in difference sample sites, values of FCB in Bay-heed were significantly higher than those in middle of bay and Bay-mouth, Luoyuan Bay. However, values of FCB in Bay-mouth were significantly less than those in middle of bay. The ratios to the par of FCB in 2003, 2004, and 2005 years were 100%, 98.0%, and 97.9%, respectively. Therefore, we considered that the pollution of FCB of surface marine water in Luoyuan Bay was not serious. 展开更多
关键词 Luoyuan Bay fecal coliform bacteria horizontal distribution annual variations
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基于CT影像儿童枢椎正常发育与变异的解剖特征
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作者 吕绍茂 蓝佐珍 +2 位作者 吴文雪 池金澄 段少银 《中国组织工程研究》 CAS 北大核心 2025年第21期4545-4551,共7页
背景:枢椎发育演变过程复杂,研究报道较少。CT成像可以显示枢椎的正常发育过程、解剖结构、发育变异与畸形,明确枢椎骨化中心出现与骺板闭合时间及其演变过程和规律具有重要的临床价值。目的:基于CT影像展示儿童枢椎正常发育与变异的解... 背景:枢椎发育演变过程复杂,研究报道较少。CT成像可以显示枢椎的正常发育过程、解剖结构、发育变异与畸形,明确枢椎骨化中心出现与骺板闭合时间及其演变过程和规律具有重要的临床价值。目的:基于CT影像展示儿童枢椎正常发育与变异的解剖结构。方法:回顾性分析2016年6月至2019年11月行颈部扫描的732例0-15岁儿童CT图像。观察指标包括枢椎齿状突、双侧椎弓、椎体骨化中心,齿突尖部二次骨化中心,椎弓、齿突基底部及后正中骺板,以及枢椎发育变异或畸形。分析与比较各项指标在不同年龄下的变化情况,并利用SPSS 17.0统计学软件包进行数据分类处理及统计学分析。结果与结论:(1)732例研究对象包括枢椎正常发育718例(98.1%),畸形或发育异常14例(1.9%);(2)枢椎5个骨化中心,其中双侧椎弓及齿突、椎体骨化中心在出生时已出现;齿突尖部二次骨化中心出现的中位年龄是5.7岁,年龄四分位差(IQR)是4.1-7岁,最早出现的为8个月22 d,最迟未出现的为12岁10个月;(3)齿突尖骺板融合的中位年龄是6岁,IQR是5-8岁,未融合最大年龄是8岁9个月,融合的最小年龄是4岁3个月;(4)双侧椎弓骺板闭合的中位年龄约3.8岁,IQR约2.9-4.6岁,闭合的最小年龄是2岁3个月,未闭合的最大年龄是6岁;(5)齿突基底部骺板闭合的中位数5.2岁,IQR为3.5-6.8岁,闭合最小年龄是2岁6个月,最晚未闭合年龄是9岁6个月;(6)后正中骺板闭合年龄中位数为1.5岁,IQR为1.0-2.1岁,最晚未闭合2例分别为2岁5个月、14岁,最早闭合为6个月20 d;(7)枢椎畸形或发育异常,包括出现副骨化中心及副骺板7例、枢椎游离骨化小骨3例、后正中骺板不闭合2例、无齿突尖部二次骨化中心2例及枢椎齿突骨化中心未出现1例;(8)提示多层螺旋CT扫描、结合多平面重组技术可以完整显示枢椎的解剖结构,评估其正常发育变异及畸形。 展开更多
关键词 枢椎 骨化中心 骺板 发育与变异 CT影像
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Quantitative Variations of Five Anthraglucosides in Rhubarb
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作者 郑俊华 黄琴 +2 位作者 张治国 高双新 楼之岑 《Journal of Chinese Pharmaceutical Sciences》 CAS 1992年第1期85-87,共3页
应用高效液相色谱法测定大黄1—5年不同生长年限、植株不同发育阶段、植株不同部分中番泻式A(sennoside A,SA),大黄酸-8-葡萄糖甙(rhein-8-O-β-D-glucoside,R8G),大黄酸甙(rheinoside)A(RA),C(RC),D(RD)等五种蒽甙类成分的含量,结果表... 应用高效液相色谱法测定大黄1—5年不同生长年限、植株不同发育阶段、植株不同部分中番泻式A(sennoside A,SA),大黄酸-8-葡萄糖甙(rhein-8-O-β-D-glucoside,R8G),大黄酸甙(rheinoside)A(RA),C(RC),D(RD)等五种蒽甙类成分的含量,结果表明:(1)大黄随生长年限的延长,五种蒽甙类成分的总含量呈递增趋势,但第二年以后增加缓慢;(2)不同发育阶段中五种蒽甙的总量以果熟期为最高;(3)大黄的根系中五种蒽甙的总含量依下列顺序递减:主根茎→细根→主根及支根→支根茎;茎部只含少量大黄酸甙 D,叶不含任何蒽甙类成分。本研究有利于确定大黄合理的采收年限和季节,以及大黄资源的合理利用。 展开更多
关键词 Rheum palmatum Anthraglucosides variations High Performance Liquid Chromatography
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Characteristics of Ozone Variations in Lhasa in Recent Years
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作者 杨勇 张勇 唐小萍 《Agricultural Science & Technology》 CAS 2013年第9期1315-1318,共4页
The variation characteristics of ozone in Lhasa in recent years were analyzed by using Brewer spectrometer observation data. The results showed that ozone was mainly distributed in 15-35 km in atmosphere in Lhasa; the... The variation characteristics of ozone in Lhasa in recent years were analyzed by using Brewer spectrometer observation data. The results showed that ozone was mainly distributed in 15-35 km in atmosphere in Lhasa; the peak value by inversion was in 21-25 km; by comparison of ozone vertical distribution in Lhasa, it can be concluded that ozone differs insignificantly in middle-to-high layers in stratosphere and the distribution is similar over 36 km. The difference can be observed from the fact that ozone concentration is higher in winter and spring compared with summer and autumn from ground to the height at 21 km. In recent 4 years, annual average of total ozone in Lhasa was of little variations and extreme values of ozone appeared in winter and spring. Monthly averages were lower in August and September, and the lower value of ozone kept longer in 2008 for 23 d. 展开更多
关键词 LHASA OZONE Variation characters
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Spatial transcriptomics combined with single-nucleus RNA sequencing reveals glial cell heterogeneity in the human spinal cord
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作者 Yali Chen Yiyong Wei +3 位作者 Jin Liu Tao Zhu Cheng Zhou Donghang Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3302-3316,共15页
Glial cells play crucial roles in regulating physiological and pathological functions,including sensation,the response to infection and acute injury,and chronic neurodegenerative disorders.Glial cells include astrocyt... Glial cells play crucial roles in regulating physiological and pathological functions,including sensation,the response to infection and acute injury,and chronic neurodegenerative disorders.Glial cells include astrocytes,microglia,and oligodendrocytes in the central nervous system,and satellite glial cells and Schwann cells in the peripheral nervous system.Despite the greater understanding of glial cell types and functional heterogeneity achieved through single-cell and single-nucleus RNA sequencing in animal models,few studies have investigated the transcriptomic profiles of glial cells in the human spinal cord.Here,we used high-throughput single-nucleus RNA sequencing and spatial transcriptomics to map the cellular and molecular heterogeneity of astrocytes,microglia,and oligodendrocytes in the human spinal cord.To explore the conservation and divergence across species,we compared these findings with those from mice.In the human spinal cord,astrocytes,microglia,and oligodendrocytes were each divided into six distinct transcriptomic subclusters.In the mouse spinal cord,astrocytes,microglia,and oligodendrocytes were divided into five,four,and five distinct transcriptomic subclusters,respectively.The comparative results revealed substantial heterogeneity in all glial cell types between humans and mice.Additionally,we detected sex differences in gene expression in human spinal cord glial cells.Specifically,in all astrocyte subtypes,the levels of NEAT1 and CHI3L1 were higher in males than in females,whereas the levels of CST3 were lower in males than in females.In all microglial subtypes,all differentially expressed genes were located on the sex chromosomes.In addition to sex-specific gene differences,the levels of MT-ND4,MT2A,MT-ATP6,MT-CO3,MT-ND2,MT-ND3,and MT-CO_(2) in all spinal cord oligodendrocyte subtypes were higher in females than in males.Collectively,the present dataset extensively characterizes glial cell heterogeneity and offers a valuable resource for exploring the cellular basis of spinal cordrelated illnesses,including chronic pain,amyotrophic lateral sclerosis,and multiple sclerosis. 展开更多
关键词 astrocyte glial cell HUMAN microglia oligodendrocyte sex differentiation single-nucleus RNA sequencing spatial transcriptomics species variation spinal cord
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