A global spherical Fourier-Legendre spectral element method is proposed to solve Poisson equations and advective flow over a sphere. In the meridional direction, Legendre polynomials are used and the region is divided...A global spherical Fourier-Legendre spectral element method is proposed to solve Poisson equations and advective flow over a sphere. In the meridional direction, Legendre polynomials are used and the region is divided into several elements. In order to avoid coordinate singularities at the north and south poles in the meridional direction, Legendre-Gauss-Radau points are chosen at the elements involving the two poles. Fourier polynomials are applied in the zonal direction for its periodicity, with only one element. Then, the partial differential equations are solved on the longitude-latitude meshes without coordinate transformation between spherical and Cartesian coordinates. For verification of the proposed method, a few Poisson equations and advective flows are tested. Firstly, the method is found to be valid for test cases with smooth solution. The results of the Poisson equations demonstrate that the present method exhibits high accuracy and exponential convergence. High- precision solutions are also obtained with near negligible numerical diffusion during the time evolution for advective flow with smooth shape. Secondly, the results of advective flow with non-smooth shape and deformational flow are also shown to be reasonable and effective. As a result, the present method is proved to be capable of solving flow through different types of elements, and thereby a desirable method with reliability and high accuracy for solving partial differential equations over a sphere.展开更多
Dear Editor,As an important fiber and oil crop,cotton has gradually developed into a model plant for studying fiber or seed trichome and polyploid evolution.Thus,strengthening cotton research is essential.Significant ...Dear Editor,As an important fiber and oil crop,cotton has gradually developed into a model plant for studying fiber or seed trichome and polyploid evolution.Thus,strengthening cotton research is essential.Significant progress has been made in the research of cotton genomics(Hu et al.,2019;Huang and Zhu,2021;Wen et al.,2022).However,further research has been hindered due to its long growth period(usually 4–6 months per generation)and large plant size(usually 0.8–1.5 m in height).展开更多
This paper presents an important investigation into car travel time affected by mixed traffic flow near a bus stop on the basis of survival analysis theory.Travel time data associated with mixed traffic characteristic...This paper presents an important investigation into car travel time affected by mixed traffic flow near a bus stop on the basis of survival analysis theory.Travel time data associated with mixed traffic characteristics near a bus stop were collected by video cameras.A hazard-based duration model was introduced to analyze the effects of mixed traffic flow on car travel time.The results indicate that mixed traffic flow impacts car travel time significantly.And the presence of bus berthing violation would delay car travel time.The proposed model can be used to forecast temporal shifts in car travel time due to changes in mixed traffic flow.The influential factors related to mixed traffic flow should be given full consideration in the planning and designing of bus stops in developing countries.展开更多
Objectives:By assessing and comparing the phenotypic changes on the stepwise acquisition of fluconazole resistant Candida albicans isolates,we could find and describe the relationship between drug resistance and biofi...Objectives:By assessing and comparing the phenotypic changes on the stepwise acquisition of fluconazole resistant Candida albicans isolates,we could find and describe the relationship between drug resistance and biofilm formation ability in a series of clonal strains.Methods:We performed antifungal susceptibility of five drugs(fluconazole,itraconazole,voriconazole,caspofungin and amphotericin B)to further verify the antifungal activity of the six isolates in vitro.Then we combined hyphal formation assay,cell surface hydrophobicity test positively related to adherence ability,and biofilm assays in vitro to observe and compare the phenotypic characteristics of our six clonal strains.Results:Biofilm capability is enhanced for four drug-intermediate strains,whereas the initial susceptible strain and the final resistant strain are both poor in adherence,hyphal growth and biofilm formation.Conclusions:It was suggested that the biofilm formation ability were not absolutely related to the degree of fluconazole resistance.展开更多
基金supported by the Shandong Post-Doctoral Innovation Fund(Grant No.201303064)the Qingdao Post-Doctoral Application Research Project+1 种基金the National Basic Research(973) Program of China(Grant No.2012CB417402 and 2010CB950402)the National Natural Science Foundation of China(Grant No.41176017)
文摘A global spherical Fourier-Legendre spectral element method is proposed to solve Poisson equations and advective flow over a sphere. In the meridional direction, Legendre polynomials are used and the region is divided into several elements. In order to avoid coordinate singularities at the north and south poles in the meridional direction, Legendre-Gauss-Radau points are chosen at the elements involving the two poles. Fourier polynomials are applied in the zonal direction for its periodicity, with only one element. Then, the partial differential equations are solved on the longitude-latitude meshes without coordinate transformation between spherical and Cartesian coordinates. For verification of the proposed method, a few Poisson equations and advective flows are tested. Firstly, the method is found to be valid for test cases with smooth solution. The results of the Poisson equations demonstrate that the present method exhibits high accuracy and exponential convergence. High- precision solutions are also obtained with near negligible numerical diffusion during the time evolution for advective flow with smooth shape. Secondly, the results of advective flow with non-smooth shape and deformational flow are also shown to be reasonable and effective. As a result, the present method is proved to be capable of solving flow through different types of elements, and thereby a desirable method with reliability and high accuracy for solving partial differential equations over a sphere.
基金supported in part by the National Natural Science Foundation of China (32100280)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang (2019R01002)the Fundamental Research Funds for the Central Universities (226-2022-00100)。
文摘Dear Editor,As an important fiber and oil crop,cotton has gradually developed into a model plant for studying fiber or seed trichome and polyploid evolution.Thus,strengthening cotton research is essential.Significant progress has been made in the research of cotton genomics(Hu et al.,2019;Huang and Zhu,2021;Wen et al.,2022).However,further research has been hindered due to its long growth period(usually 4–6 months per generation)and large plant size(usually 0.8–1.5 m in height).
基金supported by the National Basic Research Program of China (Grant No. 2012CB725400)National Natural Science Foundation of China (Grant Nos. 70901005,71131001)+1 种基金Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant Nos. 2010000110012,20090009120015)Fundamental Research Funds for the Central Universities (Grant No. 2011JBM055)
文摘This paper presents an important investigation into car travel time affected by mixed traffic flow near a bus stop on the basis of survival analysis theory.Travel time data associated with mixed traffic characteristics near a bus stop were collected by video cameras.A hazard-based duration model was introduced to analyze the effects of mixed traffic flow on car travel time.The results indicate that mixed traffic flow impacts car travel time significantly.And the presence of bus berthing violation would delay car travel time.The proposed model can be used to forecast temporal shifts in car travel time due to changes in mixed traffic flow.The influential factors related to mixed traffic flow should be given full consideration in the planning and designing of bus stops in developing countries.
基金National Science and Technology Major Project(No.2018ZX10734404-007 to Liu WD)the CAMS Initiative for Innovative Medicine[Grant No.2016-I2M-3-021 to(Liu WD&Li XF)]+2 种基金National Natural Science Foundation of China(No.81573059 to Li XF,No.81903229 to Zhou XW)the PUMC Youth Fund&Fundamental Research Funds for the Central Universities(Grant No.2017310033 to Zhou XW)the Basical Scientific Research Fund Projects of Chinese Academy of Medical Sciences(No.2018PT31013 to Liu WD).
文摘Objectives:By assessing and comparing the phenotypic changes on the stepwise acquisition of fluconazole resistant Candida albicans isolates,we could find and describe the relationship between drug resistance and biofilm formation ability in a series of clonal strains.Methods:We performed antifungal susceptibility of five drugs(fluconazole,itraconazole,voriconazole,caspofungin and amphotericin B)to further verify the antifungal activity of the six isolates in vitro.Then we combined hyphal formation assay,cell surface hydrophobicity test positively related to adherence ability,and biofilm assays in vitro to observe and compare the phenotypic characteristics of our six clonal strains.Results:Biofilm capability is enhanced for four drug-intermediate strains,whereas the initial susceptible strain and the final resistant strain are both poor in adherence,hyphal growth and biofilm formation.Conclusions:It was suggested that the biofilm formation ability were not absolutely related to the degree of fluconazole resistance.