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LONG-TERM VARIATIONS OF FOG AND MIST IN China's Mainland DURING 1951-2005 被引量:1
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作者 吴兑 吴晓京 +7 位作者 李菲 谭浩波 陈静 陈欢欢 陈慧忠 曹治强 李海燕 孙弦 《Journal of Tropical Meteorology》 SCIE 2013年第2期181-187,共7页
Fog is an important indicator of weather. Long-term variations of fog and mist were studied byanalyzing the meteorological data from 743 surface weather stations in China's Mainland during 1951-2005.In climatology... Fog is an important indicator of weather. Long-term variations of fog and mist were studied byanalyzing the meteorological data from 743 surface weather stations in China's Mainland during 1951-2005.In climatology, there are more foggy days in the southeast than in the northwest China and more in thewinter half of the year than in the summer half. The decadal change of foggy days shows regional variation.Southwest China is the region with the most foggy days, and more than 20 foggy days occur in SichuanBasin in one year. Persistent heavy fog usually appears in winter and spring over the North China Plain andNortheast China Plain. Misty days are much more frequent in the provinces south of the Yangtze River thanin the regions north of it, and there is an obvious increase of misty days after the 1980s. Southwest China isthe area with the most number of misty days, and more than 100 misty days occur in Sichuan Basin in ayear. 展开更多
关键词 China's Mainland FOG MIST long-term variation
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Long-term variations in runoff of the Syr Darya River Basin under climate change and human activities 被引量:3
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作者 Sanim BISSENBAYEVA Jilili ABUDUWAILI +1 位作者 Assel SAPAROVA Toqeer AHMED 《Journal of Arid Land》 SCIE CSCD 2021年第1期56-70,共15页
In this study,we analyzed the hydrological and meteorological data from the Syr Darya River Basin during the period of 1930–2015 to investigate variations in river runoff and the impacts of climate change and human a... In this study,we analyzed the hydrological and meteorological data from the Syr Darya River Basin during the period of 1930–2015 to investigate variations in river runoff and the impacts of climate change and human activities on river runoff.The Syr Darya River,which is supplied by snow and glacier meltwater upstream,is an important freshwater source for Central Asia,as nearly half of the population is concentrated in this area.River runoff in this arid region is sensitive to climate change and human activities.Therefore,estimation of the climatic and hydrological changes and the quantification of the impacts of climate change and human activities on river runoff are of great concern and important for regional water resources management.The long-term trends of hydrological time series from the selected 11 hydrological stations in the Syr Darya River Basin were examined by non-parametric methods,including the Pettitt change point test and Mann-Kendall trend tests.It was found that 8 out of 11 hydrological stations showed significant downward trends in river runof f.Change of river runoff variations occurred in the year around 1960.Moreover,during the study period(1930–2015),annual mean temperature,annual precipitation,and annual potential evapotranspiration in the river basin increased substantially.We employed hydrological sensitivity method to evaluate the impacts of climate change and human activities on river runoff based on precipitation and potential evapotranspiration.It was estimated that human activities accounted for over 82.6%–98.7%of the reduction in river runoff,mainly owing to water withdrawal for irrigation purpose.The observed variations in river runoff can subsequently lead to adverse ecological consequences from an ecological and regional water resources management perspective. 展开更多
关键词 river runoff variations water resources management land use/land cover changes Mann-Kendall trend test hydrological sensitivity analysis Aral Sea Central Asia
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Long-term variations of major atmospheric compositions observed at the background stations in three key areas of China 被引量:8
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作者 ZHANG Yong JIN Jun-Li +10 位作者 YAN Peng TANG Jie FANG Shuang-Xi LIN Wei-Li LOU Meng-Yun LIANG Miao ZHOU Qing JING Jun-Shan LI Ya-Nan JIA Xiao-Fang LYU Shan-Shan 《Advances in Climate Change Research》 SCIE CSCD 2020年第4期370-380,共11页
Atmospheric compositions and acid rain are closely related to atmospheric environment,weather,and climate change.In this study,the concentration levels and long-term trends of CO_(2),CH_(4),O_(3),PM_(2.5),PM_(10),and ... Atmospheric compositions and acid rain are closely related to atmospheric environment,weather,and climate change.In this study,the concentration levels and long-term trends of CO_(2),CH_(4),O_(3),PM_(2.5),PM_(10),and acid rain were presented at the Mt.Waliguan global baseline station in Qinghai,Shangdianzi and Lin'an regional background stations in the North China Plain(NCP)and the Yangtze River Delta region(YRD)of China based on the data observed until 2018.Significant increasing trends of CO_(2) were found at all of these stations.At Mt.Waliguan,the concentration levels and growth rate were consistent with the average values in the Northern Hemisphere(NH)and those observed at the Mauna Loa station in Hawaii.The CH_(4) also showed a upward tendency similar to that observed in NH.Compared with the observations at Mt.Waliguan global baseline station,the CO_(2) and CH_(4) mole fractions were higher at Shangdianzi and Lin'an regional background stations,indicating the important contributions of anthropogenic activities to the regional background level of CO_(2) and CH_(4).The annual averaged surface ozone showed increasing trends at Mt.Waliguan and Shangdianzi stations,whereas no clear trend was found at Lin'an station.Similar variations in the patterns of aerosol concentrations at Shangdianzi and Lin'an were found according to the PM_(2.5) or PM_(10) observations.Overall,the aerosol concentrations at both stations shown declining trends since the observations.However,two periods of high particle concentrations occurred in 2006-2007 and 2013-2014.The annual mean aerosol concentrations have continuously decreased after 2013-2014,indicating the effectiveness of pollution control in the NCP and YRD,especially since the implementation of the‘Action Plan for Prevention and Control of Air Pollution’in September 2013.Comparative analysis of aerosol with acid rain showed that the period with high concentrations of aerosols in the early years was consistent with that of severe acid rain pollution,suggesting that both aerosol pollution and severe acid rain are closely related to coal combustion emissions in China.As a result of the control of coal combustion emissions for acid and SO_(2),NO_(x) emissions have contributed more substantially to aerosols due to the rapid growth of vehicle ownership.A comparison of the trends of aerosols with the maximum daily 8-h average of surface ozone(MDA8)at Shangdianzi and Lin'an stations revealed the complicated relationship between aerosol reduction and ozone production,i.e.,together with the continuous improvement of particulate pollution in the NCP and YRD,the MDA8 at both stations showed a decreasing trend at first but subsequently increased after 2014 with aerosols remaining reduced.Such different variation patterns of the MDA8 with PM_(2.5)(or PM_(10))indicated the high challenge of synergic control of aerosol and ozone pollution in China. 展开更多
关键词 Atmospheric compositions Background observations long-term variation TREND Coordinated control of PM and ozone China
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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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Long-term variation of Arctic Sudden Stratospheric Warmings(SSW)and potential causes
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作者 QingRan Li ShaoDong Zhang +4 位作者 KaiMing Huang ChunMing Huang Yun Gong WenTao Tang Zheng Ma 《Earth and Planetary Physics》 EI CAS CSCD 2024年第5期742-752,共11页
Utilizing the European Centre for Medium-Range Weather Forecast(ECMWF)Reanalysis v5(ERA5),for the first time,we have confirmed close links among Sudden Stratospheric Warmings(SSWs)in the Northern Hemisphere(NH),the po... Utilizing the European Centre for Medium-Range Weather Forecast(ECMWF)Reanalysis v5(ERA5),for the first time,we have confirmed close links among Sudden Stratospheric Warmings(SSWs)in the Northern Hemisphere(NH),the polar vortices,and stratospheric Planetary Waves(PWs)by analyzing and comparing their trends.Interestingly,within overall increasing trends,the duration and strength of SSWs exhibit increasing and decreasing trends before and after the winter of 2002,respectively.To reveal possible physical mechanisms driving these trends,we analyzed the long-term trends of the winter(from December to February)polar vortices and of stratospheric PWs with zonal wave number 1.Notably,our results show that in all three time periods(the entire period of 41winters,1980 to 2020,and the two subperiods—1980-2002 and 2002-2020)enhancing SSWs were always accompanied by weakening winter polar vortices and strengthening polar PWs like Stationary Planetary Waves(SPWs)and 16-day waves,and vice versa.This is the first proof,based on ERA5 long-term trend data,that weakening polar vortices and enhancing stratospheric PWs(especially SPWs)could cause an increase in SSWs. 展开更多
关键词 sudden stratospheric warmings stationary planetary waves 16-day waves polar vortrices long-term trend correlation coefficient
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Statistical Characteristics and Long-Term Variations of Major Sudden Stratospheric Warming Events
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作者 Yuli ZHANG You YI +1 位作者 Xiaoyu REN Yi LIU 《Journal of Meteorological Research》 SCIE CSCD 2021年第3期416-427,共12页
Using NCEP/NCAR reanalysis data, we investigate the statistical characteristics and the long-term variations of major sudden stratospheric warming(SSW) events in the Northern Hemisphere. We find that the strength and ... Using NCEP/NCAR reanalysis data, we investigate the statistical characteristics and the long-term variations of major sudden stratospheric warming(SSW) events in the Northern Hemisphere. We find that the strength and duration of major SSW events have increased from 1958 to 2019 because of the strengthening of winter planetary wave activity. The frequency of the SSW events related to displacement or split of the polar vortex differs between early,middle, and late winter. Early(middle) winter is dominated by displacement(split) SSW events, while late winter sees almost equal frequency of these two types of events. This is due to the differences in the relative strength of wavenumber-1 and wavenumber-2 planetary wave activity among the three winter periods. As a result of the increase in upward planetary wave activity and the decrease in westerly winds around the polar vortex in middle winter, more SSW events tend to occur in middle winter. In addition, we reveal the influence of the downward propagation of different types of SSW events on the surface temperature anomaly. Compared with early displacement SSW events, middle split SSW events are followed by more surface cold centers in Russia, northern China, and North America. 展开更多
关键词 sudden stratospheric warming(SSW) planetary wave activity long-term variation vortex displacement vortex split
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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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Analysis of Temperature Trends and Variations in the Arabian Peninsula’s Upper Atmosphere
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作者 Abdullrahman H. Maghrabi 《Atmospheric and Climate Sciences》 2024年第1期85-100,共16页
In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the A... In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the Arabian Peninsula from January 1986 to August 2015. The mean monthly variations of the temperatures at these levels are characterised and established. The magnitudes of the annual trends of the mean temperatures for each site for the selected barometric levels are studied and statistically tested using Mann-Kendall rank statistics at different significance levels. The temperature trends at different pressure levels show that the upper troposphere and lower stratosphere are warming, while the middle troposphere is cooling which is consistent with the findings of other studies. The variations in upper air temperature observed in this study can be attributed to a range of factors, including increasing greenhouse gas concentrations, changes in atmospheric circulation patterns, variations in solar activity, aerosols and volcanic eruptions, and land use and land cover change. 展开更多
关键词 Upper-Air Temperature Variability long-term Trend Arabian Peninsula Climate Change Mann-Kendell
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Imperative for long-term management and surveillance in Kawasaki disease
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作者 Yan Pan Fu-Yong Jiao 《World Journal of Clinical Cases》 SCIE 2025年第4期61-63,共3页
Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD pat... Kawasaki disease(KD)is a significant pediatric vasculitis known for its potential to cause severe coronary artery complications.Despite the effectiveness of initial treatments,such as intravenous immunoglobulin,KD patients can experience long-term cardiovascular issues,as evidenced by a recent case report of an adult who suffered a ST-segment elevation myocardial infarction due to previous KD in the World Journal of Clinical Cases.This editorial emphasizes the critical need for long-term management and regular surveillance to prevent such complications.By drawing on recent research and case studies,we advocate for a structured approach to follow-up care that includes routine cardiac evaluations and preventive measures. 展开更多
关键词 Kawasaki disease long-term management Coronary artery aneurysm SURVEILLANCE Preventive care
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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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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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Variations in the Summer Monsoon Rainbands Across Eastern China over the Past 300 Years 被引量:1
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作者 郝志新 郑景云 葛全胜 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第4期614-620,共7页
Based on reconstructions of precipitation events from the rain and snowfall archives of the Qing Dynasty (1736-1911), the drought/flood index data mainly derived from Chinese local gazettes from 1736-2000, and the o... Based on reconstructions of precipitation events from the rain and snowfall archives of the Qing Dynasty (1736-1911), the drought/flood index data mainly derived from Chinese local gazettes from 1736-2000, and the observational data gathered since 1951, the spatial patterns of monsoon rainbands are analyzed at different time scales. Findings indicate that monsoon rainfall in northern China and the middle-lower reaches of the Yangtze River have significant inter-annual (e.g., 5-7-yr and 2-4-yr) as well as inter-decadal (e.g., 20-30-yr and quasi-10-yr) fluctuation signals. The spatial patterns in these areas also show significant cycles, such as on a 60-80-yr time scale, a reversal phase predominates the entire period from 1736-2000; on a quasi-30-yr time scale, a consistent phase was prevalent from 1736 to 2000; and on a 20-yr time scale, the summer monsoon rains show different spatial patterns before and after 1870. 展开更多
关键词 long-term variations monsoon rainbands historical documents China
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