Recently,the China Meteorological Administration(CMA)released a new Global Atmospheric Reanalysis(CRA-40)dataset for the period 1979−2018.In this study,surface relative humidity(RH)from CRA-40 and other current reanal...Recently,the China Meteorological Administration(CMA)released a new Global Atmospheric Reanalysis(CRA-40)dataset for the period 1979−2018.In this study,surface relative humidity(RH)from CRA-40 and other current reanalyses(e.g.,CFSR,ERA5,ERA-Interim,JRA-55,and MERRA-2)is comprehensively evaluated against homogenized observations over China.The results suggest that most reanalyses overestimate the observations by 15%−30%(absolute difference)over the Tibetan Plateau but underestimate the observations by 5%−10%over most of northern China.The CRA-40 performs relatively well in describing the long-term change and variance seen in the observed surface RH over China.Most of the reanalyses reproduce the observed surface RH climatology and interannual variations well,while few reanalyses can capture the observed long-term RH trends over China.Among these reanalyses,the CFSR does poorly in describing the interannual changes in the observed RH,especially in Southwest China.An empirical orthogonal function(EOF)analysis also suggests that the CRA-40 performs better than other reanalyses to capture the first two leading EOF modes revealed by the observations.The results of this study are expected to improve understanding of the strengths and weaknesses of the current reanalysis products and thus facilitate their application.展开更多
Keeping in mind the relationship between the basal metabolic rate and the change in weight in the aging process, we propose to verify the holographic description of the same. For this we set ourselves the following ob...Keeping in mind the relationship between the basal metabolic rate and the change in weight in the aging process, we propose to verify the holographic description of the same. For this we set ourselves the following objectives: Verify the correlation between total energy dissipation and energy dissipation per unit body mass, and verify the correlation between the total energy dissipation and the body mass. As a result of the data analysis, we obtained a coherent representation of our proposal. A high degree of correlation between the total energy dissipation in an organism and the basal metabolic rate/dry kg was found. Such a condition implies that the stated biological system satisfies the Holographic Principle.展开更多
Membrane proteins are an important kind of proteins embedded in the membranes of cells and play crucial roles in living organisms, such as ion channels,transporters, receptors. Because it is difficult to determinate t...Membrane proteins are an important kind of proteins embedded in the membranes of cells and play crucial roles in living organisms, such as ion channels,transporters, receptors. Because it is difficult to determinate the membrane protein's structure by wet-lab experiments,accurate and fast amino acid sequence-based computational methods are highly desired. In this paper, we report an online prediction tool called Mem Brain, whose input is the amino acid sequence. Mem Brain consists of specialized modules for predicting transmembrane helices, residue–residue contacts and relative accessible surface area of a-helical membrane proteins. Mem Brain achieves aprediction accuracy of 97.9% of ATMH, 87.1% of AP,3.2 ± 3.0 of N-score, 3.1 ± 2.8 of C-score. Mem BrainContact obtains 62%/64.1% prediction accuracy on training and independent dataset on top L/5 contact prediction,respectively. And Mem Brain-Rasa achieves Pearson correlation coefficient of 0.733 and its mean absolute error of13.593. These prediction results provide valuable hints for revealing the structure and function of membrane proteins.Mem Brain web server is free for academic use and available at www.csbio.sjtu.edu.cn/bioinf/Mem Brain/.展开更多
On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables an...On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables and the wave propagation problem is then transformed into two-dimensional （2D） symplectic eigenvalue problems, where the extended Wittrick-Williams algorithm is used to ensure that no phase propagation eigenvalues are missed during computation. Three typical cellular structures, square, triangle and hexagon, are introduced to illustrate the unique feature of the symplectic algorithm in higher-frequency calculation, which is due to the conserved properties of the structure-preserving symplectic algorithm. On the basis of the dispersion relations and phase constant surface analysis, the band structure is shown to be insensitive to the material type at lower frequencies, however, much more related at higher frequencies. This paper also demonstrates how the boundary conditions adopted in the finite element modeling process and the structures＇ configurations affect the band structures. The hexagonal cells are demonstrated to be more efficient for sound insulation at higher frequencies, while the triangular cells are preferred at lower frequencies. No complete band gaps are observed for the square cells with fixed-end boundary conditions. The analysis of phase constant surfaces guides the design of 2D cellular structures where waves at certain frequencies do not propagate in specified directions. The findings from the present study will provide invaluable guidelines for the future application of cellular structures in sound insulation.展开更多
From the realism of science, and taking the guide of EINSTEIN’s Relativity as guide, this article called in question the present theory of the sustainable development by the rational thinking of philosophy and a clos...From the realism of science, and taking the guide of EINSTEIN’s Relativity as guide, this article called in question the present theory of the sustainable development by the rational thinking of philosophy and a close logic inference. It is found that there are many paradoxes to the theory. Through more deepening and meticulous inference, we arrived at philosophic language of science about the sustainable development. The sustainable development is "non-sustainable development", and the non-sustainable development is "the best sustainable development". While carrying out philosophical principle thinking and repeating science demonstration for the sustainable development, this article got further confirmation that the existence of human being at the minimum environment cost may help them obtain motive power of the sustainable development. In fact, this foundation motive power exists in the flow of development in different organization levels, meanwhile it exists in strategy of intuition living of the ancient people. Only in relative lower environment cost to live can we get the support system of science for the sustainable development, and be able really to achieve the basic goal of the sustainable development.展开更多
Over the past decade, ultrathin lanthanide oxides （Ln2O3, Ln = La to Lu） nanomaterials have been intensively studied in the fields of rare earth materials science. This unique class of nanomaterials has shown many u...Over the past decade, ultrathin lanthanide oxides （Ln2O3, Ln = La to Lu） nanomaterials have been intensively studied in the fields of rare earth materials science. This unique class of nanomaterials has shown many unprecedented properties （big surface area, high surface effect, physical and chemical activities） and is thus being explored for numerous promising applications. In this review, a brief introduction of ultrathin Ln2O3 nanomaterials was given and their unique advantages were highlighted. Then, the typical synthetic methodologies were summarized and compared （thermal decomposition, solvothermal, soft template, co-precipition and microwave etc.）. Due to the high surface effect, some promising applications of ultmthin Ln203 nanomaterials, such as drug delivery and catalysis of CO oxidation, were reviewed. Finally, on the basis of current achievements on ultrathin Ln203 nanomaterials, personal perspectives and challenges on future research directions were proposed.展开更多
This study addresses a critical challenge in CFD-DEM simulations:the accurate assignment of drag force to fluid mesh cells when the cell size exceeds particle sizes.Traditional particle centroid method(PCM)approaches ...This study addresses a critical challenge in CFD-DEM simulations:the accurate assignment of drag force to fluid mesh cells when the cell size exceeds particle sizes.Traditional particle centroid method(PCM)approaches often lead to abrupt drag force variations as particles cross cell boundaries due to their discrete nature.To overcome this limitation,we propose a novel algorithm that computes an analytical solution for the effective projected area(EPA)of particles within computational cells,aligned with the relative velocity direction.The drag force is then proportionally scaled according to this EPA calculation.The paper presents a specific implementation case of our algorithm,focusing on scenarios where a cell vertex resides within a particle boundary.For EPA determination,we introduce an innovative classification approach based on face-windward surface relations.Extensive validation involved 100,000 test cases with varying cell-particle relative positions(all constrained by the vertex-in-particle condition),systematically classified into 18 types using our scheme.Results demonstrate that all computed EPA values remain within theoretical bounds,confirming the classification's comprehensiveness.Through 5 classic particle movement simulations,we show that our method maintains continuous EPA variation across time steps-a marked improvement over PCM's characteristic discontinuities.Implementation within the CFD-DEM framework for single-particle sedimentation yields terminal velocities that closely match experimental data while ensuring smooth drag force transitions between fluid cells.Compared to PCM,the present method reduces the relative error in terminal settling velocity by approximately 43%.Moreover,comparative studies of dual-particle sedimentation demonstrate our algorithm's superior performance relative to conventional PCM approaches.For Particle 1,the terminal vertical velocity predicted by the present method reduces the relative error by approximately 17%compared to PCM.These advances significantly enhance simulation fidelity for particle-fluid interaction problems where cell-particle size ratios challenge traditional methods.展开更多
基金This work was supported by grants from the Strategic Priority Research Program of Chinese Academy of Sciences(Grant Nos.XDA19030402 and XDA19030401)the China Meteorological Administration Special Public Welfare Research Fund(Grant No.GYHY201506002),the National Natural Science Foundation of China(Grant Nos.41675094,41975115)+1 种基金the Natural Science Foundation of Shaanxi Province(Grant No.2021JQ-166),Chinese Universities Scientific Fund(Grant No.2452019224)Open Research Fund of Key Laboratory of the Loess Plateau Soil Erosion and Water Process and Control,Ministry of Water Resources of China(Grant No.HTGY202002).
文摘Recently,the China Meteorological Administration(CMA)released a new Global Atmospheric Reanalysis(CRA-40)dataset for the period 1979−2018.In this study,surface relative humidity(RH)from CRA-40 and other current reanalyses(e.g.,CFSR,ERA5,ERA-Interim,JRA-55,and MERRA-2)is comprehensively evaluated against homogenized observations over China.The results suggest that most reanalyses overestimate the observations by 15%−30%(absolute difference)over the Tibetan Plateau but underestimate the observations by 5%−10%over most of northern China.The CRA-40 performs relatively well in describing the long-term change and variance seen in the observed surface RH over China.Most of the reanalyses reproduce the observed surface RH climatology and interannual variations well,while few reanalyses can capture the observed long-term RH trends over China.Among these reanalyses,the CFSR does poorly in describing the interannual changes in the observed RH,especially in Southwest China.An empirical orthogonal function(EOF)analysis also suggests that the CRA-40 performs better than other reanalyses to capture the first two leading EOF modes revealed by the observations.The results of this study are expected to improve understanding of the strengths and weaknesses of the current reanalysis products and thus facilitate their application.
文摘Keeping in mind the relationship between the basal metabolic rate and the change in weight in the aging process, we propose to verify the holographic description of the same. For this we set ourselves the following objectives: Verify the correlation between total energy dissipation and energy dissipation per unit body mass, and verify the correlation between the total energy dissipation and the body mass. As a result of the data analysis, we obtained a coherent representation of our proposal. A high degree of correlation between the total energy dissipation in an organism and the basal metabolic rate/dry kg was found. Such a condition implies that the stated biological system satisfies the Holographic Principle.
基金supported by the National Natural Science Foundation of China(Nos.61671288,91530321,61603161)Science and Technology Commission of Shanghai Municipality(Nos.16JC1404300,17JC1403500,16ZR1448700)
文摘Membrane proteins are an important kind of proteins embedded in the membranes of cells and play crucial roles in living organisms, such as ion channels,transporters, receptors. Because it is difficult to determinate the membrane protein's structure by wet-lab experiments,accurate and fast amino acid sequence-based computational methods are highly desired. In this paper, we report an online prediction tool called Mem Brain, whose input is the amino acid sequence. Mem Brain consists of specialized modules for predicting transmembrane helices, residue–residue contacts and relative accessible surface area of a-helical membrane proteins. Mem Brain achieves aprediction accuracy of 97.9% of ATMH, 87.1% of AP,3.2 ± 3.0 of N-score, 3.1 ± 2.8 of C-score. Mem BrainContact obtains 62%/64.1% prediction accuracy on training and independent dataset on top L/5 contact prediction,respectively. And Mem Brain-Rasa achieves Pearson correlation coefficient of 0.733 and its mean absolute error of13.593. These prediction results provide valuable hints for revealing the structure and function of membrane proteins.Mem Brain web server is free for academic use and available at www.csbio.sjtu.edu.cn/bioinf/Mem Brain/.
基金supported by the National Natural Science Foundation of China (10972182, 10772147, 10632030)the National Basic Research Program of China (2006CB 601202)+3 种基金the Doctorate Foundation of Northwestern Polytechnical University (CX200908)the Graduate Starting Seed Fund of Northwestern Polytechnical University (Z200930)the NPU Foundation for Fundamental Researchthe Open Foundation of State Key Laboratory of Structural Analysis of Industrial Equipment (GZ0802)
文摘On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables and the wave propagation problem is then transformed into two-dimensional （2D） symplectic eigenvalue problems, where the extended Wittrick-Williams algorithm is used to ensure that no phase propagation eigenvalues are missed during computation. Three typical cellular structures, square, triangle and hexagon, are introduced to illustrate the unique feature of the symplectic algorithm in higher-frequency calculation, which is due to the conserved properties of the structure-preserving symplectic algorithm. On the basis of the dispersion relations and phase constant surface analysis, the band structure is shown to be insensitive to the material type at lower frequencies, however, much more related at higher frequencies. This paper also demonstrates how the boundary conditions adopted in the finite element modeling process and the structures＇ configurations affect the band structures. The hexagonal cells are demonstrated to be more efficient for sound insulation at higher frequencies, while the triangular cells are preferred at lower frequencies. No complete band gaps are observed for the square cells with fixed-end boundary conditions. The analysis of phase constant surfaces guides the design of 2D cellular structures where waves at certain frequencies do not propagate in specified directions. The findings from the present study will provide invaluable guidelines for the future application of cellular structures in sound insulation.
基金Under the auspices of National Excellent Youth Foundation of China(No.40125003)
文摘From the realism of science, and taking the guide of EINSTEIN’s Relativity as guide, this article called in question the present theory of the sustainable development by the rational thinking of philosophy and a close logic inference. It is found that there are many paradoxes to the theory. Through more deepening and meticulous inference, we arrived at philosophic language of science about the sustainable development. The sustainable development is "non-sustainable development", and the non-sustainable development is "the best sustainable development". While carrying out philosophical principle thinking and repeating science demonstration for the sustainable development, this article got further confirmation that the existence of human being at the minimum environment cost may help them obtain motive power of the sustainable development. In fact, this foundation motive power exists in the flow of development in different organization levels, meanwhile it exists in strategy of intuition living of the ancient people. Only in relative lower environment cost to live can we get the support system of science for the sustainable development, and be able really to achieve the basic goal of the sustainable development.
基金supported by the Start-up Funding from Xi’an Jiaotong Universitythe Fundamental Research Funds for the Central Universities (2015qngz12)+1 种基金the National Natural Science Foundation of China (21371140)the China National Funds for Excellent Young Scientists (21522106)
文摘Over the past decade, ultrathin lanthanide oxides （Ln2O3, Ln = La to Lu） nanomaterials have been intensively studied in the fields of rare earth materials science. This unique class of nanomaterials has shown many unprecedented properties （big surface area, high surface effect, physical and chemical activities） and is thus being explored for numerous promising applications. In this review, a brief introduction of ultrathin Ln2O3 nanomaterials was given and their unique advantages were highlighted. Then, the typical synthetic methodologies were summarized and compared （thermal decomposition, solvothermal, soft template, co-precipition and microwave etc.）. Due to the high surface effect, some promising applications of ultmthin Ln203 nanomaterials, such as drug delivery and catalysis of CO oxidation, were reviewed. Finally, on the basis of current achievements on ultrathin Ln203 nanomaterials, personal perspectives and challenges on future research directions were proposed.
基金the National Science and Technology Major Project(2011ZX06901-003)。
文摘This study addresses a critical challenge in CFD-DEM simulations:the accurate assignment of drag force to fluid mesh cells when the cell size exceeds particle sizes.Traditional particle centroid method(PCM)approaches often lead to abrupt drag force variations as particles cross cell boundaries due to their discrete nature.To overcome this limitation,we propose a novel algorithm that computes an analytical solution for the effective projected area(EPA)of particles within computational cells,aligned with the relative velocity direction.The drag force is then proportionally scaled according to this EPA calculation.The paper presents a specific implementation case of our algorithm,focusing on scenarios where a cell vertex resides within a particle boundary.For EPA determination,we introduce an innovative classification approach based on face-windward surface relations.Extensive validation involved 100,000 test cases with varying cell-particle relative positions(all constrained by the vertex-in-particle condition),systematically classified into 18 types using our scheme.Results demonstrate that all computed EPA values remain within theoretical bounds,confirming the classification's comprehensiveness.Through 5 classic particle movement simulations,we show that our method maintains continuous EPA variation across time steps-a marked improvement over PCM's characteristic discontinuities.Implementation within the CFD-DEM framework for single-particle sedimentation yields terminal velocities that closely match experimental data while ensuring smooth drag force transitions between fluid cells.Compared to PCM,the present method reduces the relative error in terminal settling velocity by approximately 43%.Moreover,comparative studies of dual-particle sedimentation demonstrate our algorithm's superior performance relative to conventional PCM approaches.For Particle 1,the terminal vertical velocity predicted by the present method reduces the relative error by approximately 17%compared to PCM.These advances significantly enhance simulation fidelity for particle-fluid interaction problems where cell-particle size ratios challenge traditional methods.
