The present paper presents a concise summary of our recent studies on the Asian summer monsoon,with highting decadal and inter- decadal scales. The studies on the long- term variations of the Asian summer monsoon and ...The present paper presents a concise summary of our recent studies on the Asian summer monsoon,with highting decadal and inter- decadal scales. The studies on the long- term variations of the Asian summer monsoon and its impacts on the change in the summer precipitation in China are reviewed. Moreover,recent changes in the Asian summer monsoon and summer precipitation in East Asia(including Meiyu precipitation)are discussed. Finally,the future changes of the Asian summer monsoon are also pointed out in this paper.展开更多
By using the 40-year NCEP (1958-1997) grid point reanalysis meteorological data, we analyzed the inter-decadal variation on the climatic characteristics of the onset of South China Sea summer monsoon. The results are ...By using the 40-year NCEP (1958-1997) grid point reanalysis meteorological data, we analyzed the inter-decadal variation on the climatic characteristics of the onset of South China Sea summer monsoon. The results are as follows. (1) There was great difference on the onset date of the SCS summer monsoon between the first two decades and the last two decades. It was late on the 6th pentad of May for the first two decades and was on the 4th and 5th pentad of May for the next two decades. (2) Except for the third decade (1978-1987), the establishment of the monsoon rainfall was one to two pentads earlier than the onset of the summer monsoon in all other three decades. (3) The onset of the SCS monsoon is the result of the abrupt development and eastward advancement of the southwesterly monsoon over the Bay of Bengal. The four-decade analysis shows that there were abrupt development of the southwesterly monsoon over the Bay of Bengal between the 3rd and 4th pentad of May, but there was great difference between its eastward movement and its onset intensity. These may have important effect to the earlier or later onset of the SCS summer monsoon. (4) During the onset of the SCS summer monsoon, there were great difference in the upper and lower circulation feature between the first two and the next two decades. At the lower troposphere of the first two decades, the Indian-Burma trough was stronger and the center of the subtropical high was located more eastward. At the upper troposphere, the northward movement of the center of subtropical high was large and located more northward after it landed on the Indo-China Peninsula. After comparison, we can see that the circulation feature of the last two decades was favorable to the establishment and development of the SCS summer monsoon.展开更多
This study analyzes the inter-decadal variations of rainfall over southern China in spring (March-April-May) using the observed precipitation data for 1979-2004. The result shows that the variations of spring rainfall...This study analyzes the inter-decadal variations of rainfall over southern China in spring (March-April-May) using the observed precipitation data for 1979-2004. The result shows that the variations of spring rainfall over southeastern China are opposite to those over and southwestern China in both inter-annual and inter-decadal time scales. The precipitation over south- ern China exhibits an apparent inter-decadal shift in the late 1980s. The accumulated spring rainfall has reduced 30% over southeastern China after the late 1980s, whereas it has increased twice as much over southwestern China. The atmospheric circulations related to this shift show that an abnormal high at lower and middle troposphere appears over Asian middle and high latitudes, accompanied by stronger-than-normal northerly wind over eastern China. Consequently, the wet air flows from tropical oceans are weakened over southern China, resulting in less rainfall over southeastern China and more rainfall over southwestern China. Furthermore, the anomalous atmospheric circulation over Asian middle and high latitudes is closely related to the inter-decadal downward shift of Eurasian spring snow in the late 1980s, indicating that the inter-decadal shift of Eurasian spring snow in the late 1980s is probably an important factor in the decadal shift of spring rainfall over southern China.展开更多
Cirrus clouds play a crucial role in the energy balance of the Earth-atmosphere system.We investigated the spatiotemporal variations of cirrus over the South China Sea(SCS)using satellite data(MOD08,MYD08,CALIPSO)and ...Cirrus clouds play a crucial role in the energy balance of the Earth-atmosphere system.We investigated the spatiotemporal variations of cirrus over the South China Sea(SCS)using satellite data(MOD08,MYD08,CALIPSO)and reanalysis data(MERRA-2)from March 2007 to February 2015(eight years).The horizontal distribution reveals lower cirrus fraction values in the northern SCS and higher values in the southern region,with minima observed in March and April and maxima sequentially occurring in August(northern SCS,NSCS),September(middle SCS,MSCS),and December(southern SCS,SSCS).Vertically,the cirrus fraction peaks in summer and reaches its lowest levels in spring.Opaque cirrus dominates during summer in the NSCS and MSCS,comprising 53.6%and 55.9%,respectively,while the SSCS exhibits a higher frequency of opaque cirrus relative to other cloud types.Subvisible cirrus clouds have the lowest frequency year-round,whereas thin cirrus is most prominent in winter in the NSCS(46.3%)and in spring in the MSCS(45.3%).A case study from September 2021 further explores the influence of ice crystal habits on brightness temperature(BT)over the SCS.Simulations utilizing five ice crystal shapes from the ARTS DDA(Atmospheric Radiative Transfer Simulator Discrete Dipole Approximation)database and the RTTOV 12.4 radiative transfer model reveal that the 8-column-aggregate shape best represents BT in the NSCS and SSCS,while the large-block-aggregate shape performs better in the SSCS.展开更多
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,para...Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,paralysis,and respiratory failure (Morgan and Orrell,2016).展开更多
This study investigates the Stratosphere-Troposphere Exchange(STE) of water vapor,emphasizes its interdecadal variations over Asia in boreal summer,and discusses the influences of atmospheric heat sources over the Tib...This study investigates the Stratosphere-Troposphere Exchange(STE) of water vapor,emphasizes its interdecadal variations over Asia in boreal summer,and discusses the influences of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific(WNP) on them by using the Wei method with reanalysis data from the European Centre for Medium-Range Weather Forecasts(ECMWF) for the years of 1958-2001.The climatology shows that the upward transport of water vapor across the tropopause in boreal summer is the most robust over the joining area of the South Asian Peninsula and Indian-Pacific Oceans(defined as AIPO).The upward transport over there can persistently convey the abundant water vapor into the stratosphere and then influence the distribution and variation of the stratospheric water vapor.The analysis shows that interdecadal variations of the water vapor exchange over the AIPO are significant,and its abrupt change occurred in the mid-1970s and the early 1990s.In these three periods,as important channels of the water vapor exchange,the effect of Bay of Bengal-East Asia as well as South China Sea was gradually weakening,while the role of the WNP becomes more and more important.Further studies show that atmospheric heat sources over the Tibetan Plateau and the WNP are two main factors in determining the interdecadal variations of water vapor exchange.The thermal influences over the Tibetan Plateau and the WNP have been greatly adjusted over the pass 44 years.Their synthesis influences the interdecadal variations of the water vapor exchange by changing the Asian summer monsoon,but their roles vary with time and regions.Especially after 1992,the influence of heat source over the Tibetan Plateau remarkably weakens,while the heat source over the WNP dominates the across-tropopause water vapor exchange.Results have important implications for understanding the transport of other components in the atmosphere and estimating the impact of human activities(emission) on global climate.展开更多
The strongest change in Meiyu periods in the mid-lower Yangtze Basin （MLY） since 1885 occurred in the late 1970s： a stage of weak Meiyu from 1958 to 1978 abruptly transformed into a stage of plentiful Meiyu from 19...The strongest change in Meiyu periods in the mid-lower Yangtze Basin （MLY） since 1885 occurred in the late 1970s： a stage of weak Meiyu from 1958 to 1978 abruptly transformed into a stage of plentiful Meiyu from 1979 to 1999. The average Meiyu amount of the latter 21 years increased by 66% compared with that of the former 21 years, accompanied by a significant increase in the occurrence of summer floods in the MLY. This change was closely related with the frequent phenomenon of postponed Meiyu ending dates （MED） and later onset dates of high summer （ODHS） in the MLY. To a considerable degree, this reflects an abrupt change of the summer climate in East China. Further analysis showed that the preceding factors contributing to inter-annual changes in Meiyu in the two 21-year stages delimited above were also very different from each other. The causes of change were associated with the following： China’s industrialization has greatly accelerated since the 1970s, accompanied by an increase in atmospheric pollution and a reduction of the solar radiation reaching the ground. The sand area of North China has also expanded due to overgrazing. The enhanced greenhouse effect is manifested in warm winters （especially in February）. Meanwhile, the January precipitation of the MLY has for the most part increased, and El Ni？o events have occurred more frequently since the late 1970s. A correlative scatter diagram consisting of these five factors mentioned above clearly shows that the two stages with opposite Meiyu characteristics are grouped in two contrasting locations with very different environmental （land-atmosphere） conditions. It is quite possible that we are now entering a new stage of lesser Meiyu, beginning in 2000.展开更多
Halocarbons play a vital role in ozone depletion and global warming,and are regulated by the Montreal Protocol(MP)and its amendments.China has been identified as an important contributor to the halocarbon emissions,bu...Halocarbons play a vital role in ozone depletion and global warming,and are regulated by the Montreal Protocol(MP)and its amendments.China has been identified as an important contributor to the halocarbon emissions,but the regional sources of halocarbons in China are not yet well comprehended.To investigate the characteristics,emissions,and source profiles,this study conducted a field campaign in Xiamen,a coastal city in southeastern China.Higher enhancements were found in the unregulated halocarbons(CH_(3)Cl,CH_(2)Cl_(2),CHCl_(3))than in the MP eliminated species(CCl_(4),CH_(3)Br)and theMP controlled species(HCFCs,HFCs).Many of the measured halocarbons varied seasonally and regionally,depending on the anthropogenic sources and atmospheric transport.Backward trajectory analysis showed that the air masses from inland were polluted over Shandong,Hebei,and northern Fujian in the cold season,while the air masses fromthe sea in the warm season were clean.Different air masses in two seasons were associated with the halocarbon patterns in the study area.Industrial activities,especially solvent usage,were the primary sources of halocarbons.The emission hot spots in Fujian Province were concentrated in Sanming,Fuzhou,and Xiamen,and the unregulated halocarbons made the largest contribution.This study provides an insight for a deep understanding of the characteristics and potential sources of halocarbons,and for strengthened management of halocarbons in China.展开更多
Epigenetics-mediated breeding(epibreeding)involves engineering crop traits and stress responses through the targeted manipulation of key epigenetic features to enhance agricultural productivity.While conventional bree...Epigenetics-mediated breeding(epibreeding)involves engineering crop traits and stress responses through the targeted manipulation of key epigenetic features to enhance agricultural productivity.While conventional breeding methods raise concerns about reduced genetic diversity,epibreeding propels crop improvement through epigenetic variations that regulate gene expression,ultimately impacting crop yield.Epigenetic regulation in crops encompasses various modes,including histone modification,DNA modification,RNA modification,non-coding RNA,and chromatin remodeling.This review summarizes the epigenetic mechanisms underlying major agronomic traits in maize and identifies candidate epigenetic landmarks in the maize breeding process.We propose a valuable strategy for improving maize yield through epibreeding,combining CRISPR/Cas-based epigenome editing technology and Synthetic Epigenetics(SynEpi).Finally,we discuss the challenges and opportunities associated with maize trait improvement through epibreeding.展开更多
In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenario...In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenarios with non-Gaussian noise and heavy-tailed outliers.The proposed design modifies the extended Kalman filter(EKF)for the global navigation satellite system(GNSS),integrating the maximum correntropy criterion(MCC)and the variational Bayesian(VB)method.This adaptive algorithm effectively reduces non-line-of-sight(NLOS)reception contamination and improves estimation accuracy,particularly in time-varying GNSS measurements.Experimental results show that the proposed method significantly outperforms conventional approaches in estimation accuracy under heavy-tailed outliers and non-Gaussian noise.By combining MCC with VB approximation for real-time noise covariance estimation using fixed-point iteration,the VBMCEKF achieves superior filtering performance in challenging GNSS conditions.The method’s adaptability and precision make it ideal for improving satellite navigation performance in stochastic environments.展开更多
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil...Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress.展开更多
BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free r...BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free rates.AIM To assess the role of VCSD in determining success of SWL in urinary calculi.METHODS Charts review was utilized for collection of data variables.The patients were subjected to SWL,using an electromagnetic lithotripter.Mean stone density(MSD),stone heterogeneity index(SHI),and VCSD were calculated by generating regions of interest on computed tomography(CT)images.Role of these factors were determined by applying the relevant statistical tests for continuous and categorical variables and a P value of<0.05 was gauged to be statistically significant.RESULTS There were a total of 407 patients included in the analysis.The mean age of the subjects in this study was 38.89±14.61 years.In total,165 out of the 407 patients could not achieve stone free status.The successful group had a significantly lower stone volume as compared to the unsuccessful group(P<0.0001).Skin to stone distance was not dissimilar among the two groups(P=0.47).MSD was significantly lower in the successful group(P<0.0001).SHI and VCSD were both significantly higher in the successful group(P<0.0001).CONCLUSION VCSD,a useful CT based parameter,can be utilized to gauge stone fragility and hence the prediction of SWL outcomes.展开更多
In this paper,we use the solution of the even functional Minkowski problem to show that there is a minimizing affine Minkowski total variation of the function of bounded variation.Moreover,for the Minkowski total vari...In this paper,we use the solution of the even functional Minkowski problem to show that there is a minimizing affine Minkowski total variation of the function of bounded variation.Moreover,for the Minkowski total variation,we use the method of convexation to establish the same conclusion as the convex body space.展开更多
The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces....The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.展开更多
Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including at...Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050.展开更多
Benzene,toluene,ethylbenzene,and xylene(BTEX)pollution poses a serious threat to public health and the environment because of its respiratory and neurological effects,carcinogenic properties,and adverse effects on air...Benzene,toluene,ethylbenzene,and xylene(BTEX)pollution poses a serious threat to public health and the environment because of its respiratory and neurological effects,carcinogenic properties,and adverse effects on air quality.BTEX exposure is a matter of grave concern in India owing to the growing vehicular and development activities,necessitating the assessment of atmospheric concentrations and their spatial variation.This paper presents a comprehensive assessment of ambient concentrations and spatiotemporal variations of BTEX in India.The study investigates the correlation of BTEX with other criteria pollutants andmeteorological parameters,aiming to identify interrelationships and diagnostic indicators for the source characterization of BTEX emissions.Additionally,the paper categorizes various regions in India according to the Air Quality Index(AQI)based on BTEX pollution levels.The results reveal that the northern zone of India exhibits the highest levels of BTEX pollution compared to central,eastern,and western regions.In contrast,the southern zone experiences the least pollution with BTEX.Seasonal analysis indicates that winter and postmonsoon periods,characterized by lower temperatures,are associated with higher BTEX levels due to the accumulation of localized emissions.When comparing the different zones in India,high traffic emissions and localized activities,such as solvent use and solvent evaporation,are found to be the primary sources of BTEX.The findings of the current study aid in source characterization and identification,and better understanding of the region’s air quality problems,which helps in the development of focused BTEX pollution reduction and control strategies.展开更多
As a classic novel,San Guo Yan Yi raises a crucial cross-cultural communication question:how can Western readers accurately and objectively understand Zhuge Liang’s image in its overseas translation?Influenced by cul...As a classic novel,San Guo Yan Yi raises a crucial cross-cultural communication question:how can Western readers accurately and objectively understand Zhuge Liang’s image in its overseas translation?Influenced by cultural context disparities and the intervention of the translator’s subjectivity,Moss Roberts has boldly transformed and reshaped Zhuge Liang’s traditionally-perceived image.In Three Kingdoms,from the image of an omnipotent wise man,a benevolent person,and a loyal and unwavering sage,Moss Roberts constructs images of Zhuge Liang who,while possessing genuine talent and knowledge,is also narrow-minded,jealous of the able and virtuous,and has a tinge of hypocrisy,thus creating a strong tragic implication.Through comparisons,this study aims to provide a new dimension for Zhuge Liang’s image,offering references for the study of cross-cultural translation of Chinese classical literature,deepening the understanding of how cultural identities are negotiated in translation.展开更多
Based on the data of daily precipitation in 11 national ground meteorological observation stations in Jining City from 1981 to 2020,the interdecadal variation,intensity,range and spatial distribution of rainstorms in ...Based on the data of daily precipitation in 11 national ground meteorological observation stations in Jining City from 1981 to 2020,the interdecadal variation,intensity,range and spatial distribution of rainstorms in Jining City were analyzed.The results show that the number of rainstorm days and the total amount of rainstorms in Jining City had significant changes among different decades.There was a continuous upward trend from the 1980s to the early 21 st century and a decrease after the early 21 st century.Rainstorms had distinct seasonal characteristics.They were mainly concentrated in summer,especially in July and August.In terms of spatial distribution,the frequency and intensity of rainstorms in the southeastern regions were significantly higher than those in the northwestern regions.The above results can provide a scientific basis for flood control and disaster reduction in Jining City.展开更多
Embryo size is a critical trait determining not only grain yield but also the nutrition of the maize kernel.Up to the present,only a few genes have been characterized affecting the maize embryo/kernel ratio.Here,we id...Embryo size is a critical trait determining not only grain yield but also the nutrition of the maize kernel.Up to the present,only a few genes have been characterized affecting the maize embryo/kernel ratio.Here,we identify 63 genes significantly associated with maize embryo/kernel weight ratio using a genome-wide association study(GWAS).The peak GWAS signal shows that the natural variation in Zea mays COMPACT PLANT2(CT2),encoding the heterotrimeric G proteinαsubunit,is significantly associated with the Embryo/Kernel Weight Ratio(EKWR).Further analyses show that a missense mutation of CT2 increases its enzyme activity and associates with EKWR.The function of CT2 on affecting embryo/kernel weight ratio is further validated by the characterization of two ct2 mutants,for which EKWR is significantly decreased.Subsequently,the key downstream genes of CT2 are identified by combining the differential expression analysis of the ct2 mutant and quantitative trait transcript analysis in the GWAS population.In addition,the allele frequency spectrum shows that CT2 was under selective pressure during maize domestication.This study provides important genetic insights into the natural variation of maize embryo/kernel weight ratio,which could be applied in future maize breeding programs to improve grain yield and nutritional content.展开更多
基金National Basic Research Program of China(No.2010CB950404,No.2013CB430202)National Natural Science Foundation of China(No.41130960)
文摘The present paper presents a concise summary of our recent studies on the Asian summer monsoon,with highting decadal and inter- decadal scales. The studies on the long- term variations of the Asian summer monsoon and its impacts on the change in the summer precipitation in China are reviewed. Moreover,recent changes in the Asian summer monsoon and summer precipitation in East Asia(including Meiyu precipitation)are discussed. Finally,the future changes of the Asian summer monsoon are also pointed out in this paper.
基金National Scaling Project A The Scientific Experiment on South China Sea Monsoon Part I from the fund for (G1998040900)
文摘By using the 40-year NCEP (1958-1997) grid point reanalysis meteorological data, we analyzed the inter-decadal variation on the climatic characteristics of the onset of South China Sea summer monsoon. The results are as follows. (1) There was great difference on the onset date of the SCS summer monsoon between the first two decades and the last two decades. It was late on the 6th pentad of May for the first two decades and was on the 4th and 5th pentad of May for the next two decades. (2) Except for the third decade (1978-1987), the establishment of the monsoon rainfall was one to two pentads earlier than the onset of the summer monsoon in all other three decades. (3) The onset of the SCS monsoon is the result of the abrupt development and eastward advancement of the southwesterly monsoon over the Bay of Bengal. The four-decade analysis shows that there were abrupt development of the southwesterly monsoon over the Bay of Bengal between the 3rd and 4th pentad of May, but there was great difference between its eastward movement and its onset intensity. These may have important effect to the earlier or later onset of the SCS summer monsoon. (4) During the onset of the SCS summer monsoon, there were great difference in the upper and lower circulation feature between the first two and the next two decades. At the lower troposphere of the first two decades, the Indian-Burma trough was stronger and the center of the subtropical high was located more eastward. At the upper troposphere, the northward movement of the center of subtropical high was large and located more northward after it landed on the Indo-China Peninsula. After comparison, we can see that the circulation feature of the last two decades was favorable to the establishment and development of the SCS summer monsoon.
基金supported by National Basic Research Program of China (Grant No. 2007CB411505)National Natural Science Foundation of China (Grant No. 40921003)Basic Research Fund of Chinese Academy of Meteorological Sciences (Grant No. 2010Z001)
文摘This study analyzes the inter-decadal variations of rainfall over southern China in spring (March-April-May) using the observed precipitation data for 1979-2004. The result shows that the variations of spring rainfall over southeastern China are opposite to those over and southwestern China in both inter-annual and inter-decadal time scales. The precipitation over south- ern China exhibits an apparent inter-decadal shift in the late 1980s. The accumulated spring rainfall has reduced 30% over southeastern China after the late 1980s, whereas it has increased twice as much over southwestern China. The atmospheric circulations related to this shift show that an abnormal high at lower and middle troposphere appears over Asian middle and high latitudes, accompanied by stronger-than-normal northerly wind over eastern China. Consequently, the wet air flows from tropical oceans are weakened over southern China, resulting in less rainfall over southeastern China and more rainfall over southwestern China. Furthermore, the anomalous atmospheric circulation over Asian middle and high latitudes is closely related to the inter-decadal downward shift of Eurasian spring snow in the late 1980s, indicating that the inter-decadal shift of Eurasian spring snow in the late 1980s is probably an important factor in the decadal shift of spring rainfall over southern China.
基金supported by the National Natural Science Foundation of China(Grant Nos.42027804,41775026,and 41075012)。
文摘Cirrus clouds play a crucial role in the energy balance of the Earth-atmosphere system.We investigated the spatiotemporal variations of cirrus over the South China Sea(SCS)using satellite data(MOD08,MYD08,CALIPSO)and reanalysis data(MERRA-2)from March 2007 to February 2015(eight years).The horizontal distribution reveals lower cirrus fraction values in the northern SCS and higher values in the southern region,with minima observed in March and April and maxima sequentially occurring in August(northern SCS,NSCS),September(middle SCS,MSCS),and December(southern SCS,SSCS).Vertically,the cirrus fraction peaks in summer and reaches its lowest levels in spring.Opaque cirrus dominates during summer in the NSCS and MSCS,comprising 53.6%and 55.9%,respectively,while the SSCS exhibits a higher frequency of opaque cirrus relative to other cloud types.Subvisible cirrus clouds have the lowest frequency year-round,whereas thin cirrus is most prominent in winter in the NSCS(46.3%)and in spring in the MSCS(45.3%).A case study from September 2021 further explores the influence of ice crystal habits on brightness temperature(BT)over the SCS.Simulations utilizing five ice crystal shapes from the ARTS DDA(Atmospheric Radiative Transfer Simulator Discrete Dipole Approximation)database and the RTTOV 12.4 radiative transfer model reveal that the 8-column-aggregate shape best represents BT in the NSCS and SSCS,while the large-block-aggregate shape performs better in the SSCS.
文摘Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,paralysis,and respiratory failure (Morgan and Orrell,2016).
基金the National Basic Science Key Program in China (Grant No.2006CB403600)the National Natural Science Foundation of China (Grant Nos.40633018 and 40705023)
文摘This study investigates the Stratosphere-Troposphere Exchange(STE) of water vapor,emphasizes its interdecadal variations over Asia in boreal summer,and discusses the influences of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific(WNP) on them by using the Wei method with reanalysis data from the European Centre for Medium-Range Weather Forecasts(ECMWF) for the years of 1958-2001.The climatology shows that the upward transport of water vapor across the tropopause in boreal summer is the most robust over the joining area of the South Asian Peninsula and Indian-Pacific Oceans(defined as AIPO).The upward transport over there can persistently convey the abundant water vapor into the stratosphere and then influence the distribution and variation of the stratospheric water vapor.The analysis shows that interdecadal variations of the water vapor exchange over the AIPO are significant,and its abrupt change occurred in the mid-1970s and the early 1990s.In these three periods,as important channels of the water vapor exchange,the effect of Bay of Bengal-East Asia as well as South China Sea was gradually weakening,while the role of the WNP becomes more and more important.Further studies show that atmospheric heat sources over the Tibetan Plateau and the WNP are two main factors in determining the interdecadal variations of water vapor exchange.The thermal influences over the Tibetan Plateau and the WNP have been greatly adjusted over the pass 44 years.Their synthesis influences the interdecadal variations of the water vapor exchange by changing the Asian summer monsoon,but their roles vary with time and regions.Especially after 1992,the influence of heat source over the Tibetan Plateau remarkably weakens,while the heat source over the WNP dominates the across-tropopause water vapor exchange.Results have important implications for understanding the transport of other components in the atmosphere and estimating the impact of human activities(emission) on global climate.
基金supported by the National Natural Science Foundation of China (Grant No40233037)
文摘The strongest change in Meiyu periods in the mid-lower Yangtze Basin （MLY） since 1885 occurred in the late 1970s： a stage of weak Meiyu from 1958 to 1978 abruptly transformed into a stage of plentiful Meiyu from 1979 to 1999. The average Meiyu amount of the latter 21 years increased by 66% compared with that of the former 21 years, accompanied by a significant increase in the occurrence of summer floods in the MLY. This change was closely related with the frequent phenomenon of postponed Meiyu ending dates （MED） and later onset dates of high summer （ODHS） in the MLY. To a considerable degree, this reflects an abrupt change of the summer climate in East China. Further analysis showed that the preceding factors contributing to inter-annual changes in Meiyu in the two 21-year stages delimited above were also very different from each other. The causes of change were associated with the following： China’s industrialization has greatly accelerated since the 1970s, accompanied by an increase in atmospheric pollution and a reduction of the solar radiation reaching the ground. The sand area of North China has also expanded due to overgrazing. The enhanced greenhouse effect is manifested in warm winters （especially in February）. Meanwhile, the January precipitation of the MLY has for the most part increased, and El Ni？o events have occurred more frequently since the late 1970s. A correlative scatter diagram consisting of these five factors mentioned above clearly shows that the two stages with opposite Meiyu characteristics are grouped in two contrasting locations with very different environmental （land-atmosphere） conditions. It is quite possible that we are now entering a new stage of lesser Meiyu, beginning in 2000.
基金supported by the National Natural Science Foundation of China(Nos.42030707,72394404)the International Partnership Program of the Chinese Academy of Sciences(No.121311KYSB20190029)the Fundamental Research Fund for the Central Universities(Nos.20720210083,20720210082).
文摘Halocarbons play a vital role in ozone depletion and global warming,and are regulated by the Montreal Protocol(MP)and its amendments.China has been identified as an important contributor to the halocarbon emissions,but the regional sources of halocarbons in China are not yet well comprehended.To investigate the characteristics,emissions,and source profiles,this study conducted a field campaign in Xiamen,a coastal city in southeastern China.Higher enhancements were found in the unregulated halocarbons(CH_(3)Cl,CH_(2)Cl_(2),CHCl_(3))than in the MP eliminated species(CCl_(4),CH_(3)Br)and theMP controlled species(HCFCs,HFCs).Many of the measured halocarbons varied seasonally and regionally,depending on the anthropogenic sources and atmospheric transport.Backward trajectory analysis showed that the air masses from inland were polluted over Shandong,Hebei,and northern Fujian in the cold season,while the air masses fromthe sea in the warm season were clean.Different air masses in two seasons were associated with the halocarbon patterns in the study area.Industrial activities,especially solvent usage,were the primary sources of halocarbons.The emission hot spots in Fujian Province were concentrated in Sanming,Fuzhou,and Xiamen,and the unregulated halocarbons made the largest contribution.This study provides an insight for a deep understanding of the characteristics and potential sources of halocarbons,and for strengthened management of halocarbons in China.
基金supported by funding from the National Key R&D Program of China(2023ZD0407304)the Sci-Tech Innovation 2030 Agenda(2022ZD0115703)Fundamental Research Funds for Central Non-Profit of Chinese Academy of Agricultural Sciences(Y2023PT20).
文摘Epigenetics-mediated breeding(epibreeding)involves engineering crop traits and stress responses through the targeted manipulation of key epigenetic features to enhance agricultural productivity.While conventional breeding methods raise concerns about reduced genetic diversity,epibreeding propels crop improvement through epigenetic variations that regulate gene expression,ultimately impacting crop yield.Epigenetic regulation in crops encompasses various modes,including histone modification,DNA modification,RNA modification,non-coding RNA,and chromatin remodeling.This review summarizes the epigenetic mechanisms underlying major agronomic traits in maize and identifies candidate epigenetic landmarks in the maize breeding process.We propose a valuable strategy for improving maize yield through epibreeding,combining CRISPR/Cas-based epigenome editing technology and Synthetic Epigenetics(SynEpi).Finally,we discuss the challenges and opportunities associated with maize trait improvement through epibreeding.
基金supported by the National Science and Technology Council,Taiwan under grants NSTC 111-2221-E-019-047 and NSTC 112-2221-E-019-030.
文摘In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenarios with non-Gaussian noise and heavy-tailed outliers.The proposed design modifies the extended Kalman filter(EKF)for the global navigation satellite system(GNSS),integrating the maximum correntropy criterion(MCC)and the variational Bayesian(VB)method.This adaptive algorithm effectively reduces non-line-of-sight(NLOS)reception contamination and improves estimation accuracy,particularly in time-varying GNSS measurements.Experimental results show that the proposed method significantly outperforms conventional approaches in estimation accuracy under heavy-tailed outliers and non-Gaussian noise.By combining MCC with VB approximation for real-time noise covariance estimation using fixed-point iteration,the VBMCEKF achieves superior filtering performance in challenging GNSS conditions.The method’s adaptability and precision make it ideal for improving satellite navigation performance in stochastic environments.
基金funded by the National Natural Science Foundation of China(grant no.32270238 and 31870311).
文摘Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress.
文摘BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free rates.AIM To assess the role of VCSD in determining success of SWL in urinary calculi.METHODS Charts review was utilized for collection of data variables.The patients were subjected to SWL,using an electromagnetic lithotripter.Mean stone density(MSD),stone heterogeneity index(SHI),and VCSD were calculated by generating regions of interest on computed tomography(CT)images.Role of these factors were determined by applying the relevant statistical tests for continuous and categorical variables and a P value of<0.05 was gauged to be statistically significant.RESULTS There were a total of 407 patients included in the analysis.The mean age of the subjects in this study was 38.89±14.61 years.In total,165 out of the 407 patients could not achieve stone free status.The successful group had a significantly lower stone volume as compared to the unsuccessful group(P<0.0001).Skin to stone distance was not dissimilar among the two groups(P=0.47).MSD was significantly lower in the successful group(P<0.0001).SHI and VCSD were both significantly higher in the successful group(P<0.0001).CONCLUSION VCSD,a useful CT based parameter,can be utilized to gauge stone fragility and hence the prediction of SWL outcomes.
基金Supported in part by NSFC(No.11971005)the Fundamental Research Funds for the Central Universities(Nos.GK202101008,GK202102012)。
文摘In this paper,we use the solution of the even functional Minkowski problem to show that there is a minimizing affine Minkowski total variation of the function of bounded variation.Moreover,for the Minkowski total variation,we use the method of convexation to establish the same conclusion as the convex body space.
基金Supported by NSFC(No.12171062)the Natural Science Foundation of Chongqing(No.CSTB2022NSCQ-JQX0004)+1 种基金the Chongqing Talent Support Program(No.cstc2024ycjh-bgzxm0121)Science and Technology Project of Chongqing Education Committee(No.KJZD-M202300503)。
文摘The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.
基金supported by the Basic Science Center Project of the National Natural Science Foundation of China(42388102)the National Natural Science Foundation of China(42174030)+2 种基金the Special Fund of Hubei Luojia Laboratory(220100020)the Major Science and Technology Program for Hubei Province(2022AAA002)the Fundamental Research Funds for the Central Universities of China(2042022dx0001 and 2042023kfyq01)。
文摘Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050.
文摘Benzene,toluene,ethylbenzene,and xylene(BTEX)pollution poses a serious threat to public health and the environment because of its respiratory and neurological effects,carcinogenic properties,and adverse effects on air quality.BTEX exposure is a matter of grave concern in India owing to the growing vehicular and development activities,necessitating the assessment of atmospheric concentrations and their spatial variation.This paper presents a comprehensive assessment of ambient concentrations and spatiotemporal variations of BTEX in India.The study investigates the correlation of BTEX with other criteria pollutants andmeteorological parameters,aiming to identify interrelationships and diagnostic indicators for the source characterization of BTEX emissions.Additionally,the paper categorizes various regions in India according to the Air Quality Index(AQI)based on BTEX pollution levels.The results reveal that the northern zone of India exhibits the highest levels of BTEX pollution compared to central,eastern,and western regions.In contrast,the southern zone experiences the least pollution with BTEX.Seasonal analysis indicates that winter and postmonsoon periods,characterized by lower temperatures,are associated with higher BTEX levels due to the accumulation of localized emissions.When comparing the different zones in India,high traffic emissions and localized activities,such as solvent use and solvent evaporation,are found to be the primary sources of BTEX.The findings of the current study aid in source characterization and identification,and better understanding of the region’s air quality problems,which helps in the development of focused BTEX pollution reduction and control strategies.
文摘As a classic novel,San Guo Yan Yi raises a crucial cross-cultural communication question:how can Western readers accurately and objectively understand Zhuge Liang’s image in its overseas translation?Influenced by cultural context disparities and the intervention of the translator’s subjectivity,Moss Roberts has boldly transformed and reshaped Zhuge Liang’s traditionally-perceived image.In Three Kingdoms,from the image of an omnipotent wise man,a benevolent person,and a loyal and unwavering sage,Moss Roberts constructs images of Zhuge Liang who,while possessing genuine talent and knowledge,is also narrow-minded,jealous of the able and virtuous,and has a tinge of hypocrisy,thus creating a strong tragic implication.Through comparisons,this study aims to provide a new dimension for Zhuge Liang’s image,offering references for the study of cross-cultural translation of Chinese classical literature,deepening the understanding of how cultural identities are negotiated in translation.
基金the Project of Jining Meteorological Bureau(2023JNZL09).
文摘Based on the data of daily precipitation in 11 national ground meteorological observation stations in Jining City from 1981 to 2020,the interdecadal variation,intensity,range and spatial distribution of rainstorms in Jining City were analyzed.The results show that the number of rainstorm days and the total amount of rainstorms in Jining City had significant changes among different decades.There was a continuous upward trend from the 1980s to the early 21 st century and a decrease after the early 21 st century.Rainstorms had distinct seasonal characteristics.They were mainly concentrated in summer,especially in July and August.In terms of spatial distribution,the frequency and intensity of rainstorms in the southeastern regions were significantly higher than those in the northwestern regions.The above results can provide a scientific basis for flood control and disaster reduction in Jining City.
基金supported by National Key Research and Development Program of China(2023YFF1000400)National Natural Science Foundation of China(32101693)+2 种基金Key Research and Development Program of Shaanxi(2021ZDLNY01-06)Agricultural Science and Technology Innovation Program of CAAS(CAAS-ZDRW202004)supported by Hatch project(1019088).
文摘Embryo size is a critical trait determining not only grain yield but also the nutrition of the maize kernel.Up to the present,only a few genes have been characterized affecting the maize embryo/kernel ratio.Here,we identify 63 genes significantly associated with maize embryo/kernel weight ratio using a genome-wide association study(GWAS).The peak GWAS signal shows that the natural variation in Zea mays COMPACT PLANT2(CT2),encoding the heterotrimeric G proteinαsubunit,is significantly associated with the Embryo/Kernel Weight Ratio(EKWR).Further analyses show that a missense mutation of CT2 increases its enzyme activity and associates with EKWR.The function of CT2 on affecting embryo/kernel weight ratio is further validated by the characterization of two ct2 mutants,for which EKWR is significantly decreased.Subsequently,the key downstream genes of CT2 are identified by combining the differential expression analysis of the ct2 mutant and quantitative trait transcript analysis in the GWAS population.In addition,the allele frequency spectrum shows that CT2 was under selective pressure during maize domestication.This study provides important genetic insights into the natural variation of maize embryo/kernel weight ratio,which could be applied in future maize breeding programs to improve grain yield and nutritional content.
