The morphological changes of deep-water channels have an important influence on the distributions of channel sand reservoirs,so it is important to explore the morphological change process of deep-water channel for the...The morphological changes of deep-water channels have an important influence on the distributions of channel sand reservoirs,so it is important to explore the morphological change process of deep-water channel for the exploration and development of deep-water oil and gas.Based on a typical sinuous Quaternary channel(Channel I)in the Taranaki Basin,New Zealand,a variety of seismic interpretation techniques were applied to quantitatively characterize the morphological characteristics of the Channel I,and the relationships between the quantitative parameters and the morphological changes of the Channel I,as well as the controlling factors affecting those morphological changes,were discussed.The results are as follows:(1)in the quantitative analysis,six parameters were selected:the channel depth,width,sinuosity,and aspect ratio(width/depth),the channel swing amplitude(λ)and the channel bend frequency(ω);(2)according to the quantitative morphological parameters of the channel(mainly including three parameters such as channel sinuosity,ωandλ),the Channel I was divided into three types:the low-sinuous channel(LSC),the high-sinuous channel(HSC),the moderate-sinuous channel(MSC).U-shaped channel cross-sections developed in the LSC,V-shaped channel cross-sections developed in the HSC,including inclined-V and symmetric-V cross-sections,and dish-shaped channel cross-sections developed in the MSC;(3)the morphological characteristics of the LSC and MSC were related to their widths and depths,while the morphology of the HSC was greatly affected by the channel width,a change in depth did not affect the HSC morphology;(4)the morphological changes of the Channel I were controlled mainly by the slope gradient,the restricted capacity of the channel and the differential in fluid properties.展开更多
To the Editor:With the aging of the population,the prevalence of Alzheimer’s disease(AD)has increased significantly.Mild cognitive impairment(MCI)is the transition period between normal aging and dementia.[1]Quantita...To the Editor:With the aging of the population,the prevalence of Alzheimer’s disease(AD)has increased significantly.Mild cognitive impairment(MCI)is the transition period between normal aging and dementia.[1]Quantitative susceptibility mapping(QSM)allows for the direct measurement of iron metabolism disorders and iron deposition in AD brain tissue,represented as susceptibility(SUS).Voxel-based morphometry(VBM)is widely applied to evaluate gray and white matter lesions in the brain,reflecting differences in the corresponding anatomical structures by quantitatively calculating and analyzing the density or volume of brain gray/white matter for each voxel in the T1WI three-dimensional magnetization prepared rapid acquisition gradient echo(T1WI-3D-MP RAGE)sequence.Herein,we investigated the difference in brain microstructural changes in patients with AD and MCI using QSM and VBM,combined with neuropsychological test results,to evaluate the diagnostic value of QSM and VBM.展开更多
The morphology of the Modaomen Estuary(ME)has undergone drastic changes in recent decades,and quantifying the contribution of human activities and natural processes is crucial for estuary management.Using Landsat imag...The morphology of the Modaomen Estuary(ME)has undergone drastic changes in recent decades,and quantifying the contribution of human activities and natural processes is crucial for estuary management.Using Landsat images,chart data,and hydrological and meteorological data,this study analyzed the evolution of the shoreline and subaqueous topography of the ME and attempted to quantify the extent of the contributions of human activities.The results show that local human activities dominated morphological evolution in some periods.From 1973 to 2003,the shoreline advanced rapidly seaward,resulting in approximately half of the water area being converted into land.Human activity is critical to this process,with the direct contribution of local land reclamation projects reaching more than 85%.After 2003,the shoreline remained relatively stable,probably due to a decrease in land reclamation projects.Regarding the evolution of subaqueous topography,the shoals in the estuary were heavily silted and gradually disappeared during 1983–2003,and the waterways narrowed and deepened.The average siltation rate decreased from 15.43 mm/a to-1.02 mm/a,indicating that the ME changed from sedimentation to slight erosion.By detecting variations of sediment load,we found that upstream human activities reduced river sediment,while downstream human activities significantly increased sediment input to the ME,leaving little change in the actual sediment input to the ME for a relatively long period.In addition,based on the empirical relationship between the sediment input and siltation rate,local human activities influenced the shift in the siltation state more than upstream and downstream human activities did.These findings suggest that more attention should be paid to local human activities to improve the estuarine management in the ME.展开更多
Marked variations in the 3-dimensional(3D)shape of corn leaves can be discerned as a function of various influences,including genetics,environmental factors,and the management of cultivation processes.However,the caus...Marked variations in the 3-dimensional(3D)shape of corn leaves can be discerned as a function of various influences,including genetics,environmental factors,and the management of cultivation processes.However,the causes of these variations remain unclear,primarily due to the absence of quantitative methods to describe the 3D spatial morphology of leaves.To address this issue,this study acquired 3D digitized data of ear-position leaves from 478 corn inbred lines during the grain-filling stage.We propose quantitative calculation methods for 13 3D leaf shape features,such as the leaf length,3D leaf area,leaf inclination angle,blade-included angle,blade self-twisting,blade planarity,and margin amplitude.Correlation analysis,cluster analysis,and heritability analysis were conducted among the 13 leaf traits.Leaf morphology differences among subpopulations of the inbred lines were also analyzed.The results revealed that the 3D leaf traits are capable of revealing the morphological differences among different leaf surfaces,and the genetic analysis revealed that 84.62%of the 3D phenotypic traits of ear-position leaves had a heritability greater than 0.3.However,the majority of 3D leaf shape traits were strongly affected by environmental conditions.Overall,this study quantitatively investigated 3D leaf shape in corn,providing a reliable basis for further research on the genetic regulation of corn leaf morphology and advancing the understanding of the complex interplay among crop genetics,phenotypes,and the environment.展开更多
基金The National Natural Science Foundation of China under contract Nos 42077410,41872112 and 42002031the Key Scientific Research Projects in University of Henan Province under contract No.18A170007.
文摘The morphological changes of deep-water channels have an important influence on the distributions of channel sand reservoirs,so it is important to explore the morphological change process of deep-water channel for the exploration and development of deep-water oil and gas.Based on a typical sinuous Quaternary channel(Channel I)in the Taranaki Basin,New Zealand,a variety of seismic interpretation techniques were applied to quantitatively characterize the morphological characteristics of the Channel I,and the relationships between the quantitative parameters and the morphological changes of the Channel I,as well as the controlling factors affecting those morphological changes,were discussed.The results are as follows:(1)in the quantitative analysis,six parameters were selected:the channel depth,width,sinuosity,and aspect ratio(width/depth),the channel swing amplitude(λ)and the channel bend frequency(ω);(2)according to the quantitative morphological parameters of the channel(mainly including three parameters such as channel sinuosity,ωandλ),the Channel I was divided into three types:the low-sinuous channel(LSC),the high-sinuous channel(HSC),the moderate-sinuous channel(MSC).U-shaped channel cross-sections developed in the LSC,V-shaped channel cross-sections developed in the HSC,including inclined-V and symmetric-V cross-sections,and dish-shaped channel cross-sections developed in the MSC;(3)the morphological characteristics of the LSC and MSC were related to their widths and depths,while the morphology of the HSC was greatly affected by the channel width,a change in depth did not affect the HSC morphology;(4)the morphological changes of the Channel I were controlled mainly by the slope gradient,the restricted capacity of the channel and the differential in fluid properties.
基金supported by“1+X”program for Clinical Competency Enhancement–Improvement of Clinical Technology Project,The Second Hospital of Dalian Medical University(No.2022LCJSGC04)“Xingliao Talent Plan”Medical Master Project of Liaoning Province(No.YXMJ-QN-16)Fundamental Scientific Research Project of Liaoning Provincial Department of Education(No.LJ212410161028).
文摘To the Editor:With the aging of the population,the prevalence of Alzheimer’s disease(AD)has increased significantly.Mild cognitive impairment(MCI)is the transition period between normal aging and dementia.[1]Quantitative susceptibility mapping(QSM)allows for the direct measurement of iron metabolism disorders and iron deposition in AD brain tissue,represented as susceptibility(SUS).Voxel-based morphometry(VBM)is widely applied to evaluate gray and white matter lesions in the brain,reflecting differences in the corresponding anatomical structures by quantitatively calculating and analyzing the density or volume of brain gray/white matter for each voxel in the T1WI three-dimensional magnetization prepared rapid acquisition gradient echo(T1WI-3D-MP RAGE)sequence.Herein,we investigated the difference in brain microstructural changes in patients with AD and MCI using QSM and VBM,combined with neuropsychological test results,to evaluate the diagnostic value of QSM and VBM.
基金The National Natural Science Foundation of China under contract Nos 41876205,42106169 and 41890851the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)under contract Nos GML2019ZD0305 and GML2019ZD0303the Project of State Key Laboratory of Tropical Oceanography under contract Nos LTOZZ2102 and LTOZZ2202.
文摘The morphology of the Modaomen Estuary(ME)has undergone drastic changes in recent decades,and quantifying the contribution of human activities and natural processes is crucial for estuary management.Using Landsat images,chart data,and hydrological and meteorological data,this study analyzed the evolution of the shoreline and subaqueous topography of the ME and attempted to quantify the extent of the contributions of human activities.The results show that local human activities dominated morphological evolution in some periods.From 1973 to 2003,the shoreline advanced rapidly seaward,resulting in approximately half of the water area being converted into land.Human activity is critical to this process,with the direct contribution of local land reclamation projects reaching more than 85%.After 2003,the shoreline remained relatively stable,probably due to a decrease in land reclamation projects.Regarding the evolution of subaqueous topography,the shoals in the estuary were heavily silted and gradually disappeared during 1983–2003,and the waterways narrowed and deepened.The average siltation rate decreased from 15.43 mm/a to-1.02 mm/a,indicating that the ME changed from sedimentation to slight erosion.By detecting variations of sediment load,we found that upstream human activities reduced river sediment,while downstream human activities significantly increased sediment input to the ME,leaving little change in the actual sediment input to the ME for a relatively long period.In addition,based on the empirical relationship between the sediment input and siltation rate,local human activities influenced the shift in the siltation state more than upstream and downstream human activities did.These findings suggest that more attention should be paid to local human activities to improve the estuarine management in the ME.
基金partially supported by the National Key R&D Program of China(2021YFD1200700)the Construction of Collaborative Innovation Center of Beijing Academy of Agricultural and Forestry Sciences(KJCX20240406)+2 种基金the Science and Technology Innovation SpecialConstruction Funded Prog-ram of Beijing Academy of Agriculture and Forestry Sciences(KJCX20220401)the National Natural Science Foundation of China(32071891)the Earmarked Fund(CARS-02 and CARS-54).
文摘Marked variations in the 3-dimensional(3D)shape of corn leaves can be discerned as a function of various influences,including genetics,environmental factors,and the management of cultivation processes.However,the causes of these variations remain unclear,primarily due to the absence of quantitative methods to describe the 3D spatial morphology of leaves.To address this issue,this study acquired 3D digitized data of ear-position leaves from 478 corn inbred lines during the grain-filling stage.We propose quantitative calculation methods for 13 3D leaf shape features,such as the leaf length,3D leaf area,leaf inclination angle,blade-included angle,blade self-twisting,blade planarity,and margin amplitude.Correlation analysis,cluster analysis,and heritability analysis were conducted among the 13 leaf traits.Leaf morphology differences among subpopulations of the inbred lines were also analyzed.The results revealed that the 3D leaf traits are capable of revealing the morphological differences among different leaf surfaces,and the genetic analysis revealed that 84.62%of the 3D phenotypic traits of ear-position leaves had a heritability greater than 0.3.However,the majority of 3D leaf shape traits were strongly affected by environmental conditions.Overall,this study quantitatively investigated 3D leaf shape in corn,providing a reliable basis for further research on the genetic regulation of corn leaf morphology and advancing the understanding of the complex interplay among crop genetics,phenotypes,and the environment.
