It is estimated that chronic kidney disease(CKD)will be the fifth leading cause of death in the world by 2040[1].Early recognition and intervention for kidney damage are essential.Estimated glomerular filtration rate(...It is estimated that chronic kidney disease(CKD)will be the fifth leading cause of death in the world by 2040[1].Early recognition and intervention for kidney damage are essential.Estimated glomerular filtration rate(eGFR)can be calculated by measuring blood creatinine to evaluate glomerular function,and urinary N-acetyl-β-δ-glucosaminidase(UNAG)level is generally recognized as a marker of renal tubular injury.Exposure to lead(Pb)and cadmium(Cd)can damage renal function,leading to a decrease in eGFR and an increase in UNAG[2].Both Pb and Cd are easily accumulated in the body and then slowly released by the kidneys and excreted.So,urinary Pb(UPb)and Cd(UCd)levels can be used as biomarkers of exposure[3,4].展开更多
We investigate the adiabatic enhanced compression of ultrashort pulses from a distributed feedback laser operated at 1550 nm in fibres with slowly decreasing dispersion (FSDD). High-quality pulse compressions from 4.4...We investigate the adiabatic enhanced compression of ultrashort pulses from a distributed feedback laser operated at 1550 nm in fibres with slowly decreasing dispersion (FSDD). High-quality pulse compressions from 4.4 ps down to 1.1ps in a l00m FSDD and from 4.4ps down to 830fs in a 500m FSDD are obtained. The Raman self frequency shift of femtosecond pulses in the compression is observed. Theoretical analyses are in good agreement with experimental results.展开更多
A double perturbation strategy is presented to solve the asymptotic solutions of a Johnson-Segalman （J-S） fluid through a slowly varying pipe. First, a small parameter of the slowly varying angle is taken as the sma...A double perturbation strategy is presented to solve the asymptotic solutions of a Johnson-Segalman （J-S） fluid through a slowly varying pipe. First, a small parameter of the slowly varying angle is taken as the small perturbation parameter, and then the second-order asymptotic solution of the flow of a Newtonian fluid through a slowly varying pipe is obtained in the first perturbation strategy. Second, the viscoelastic parameter is selected as the small perturbation parameter in the second perturbation strategy to solve the asymptotic solution of the flow of a J-S fluid through a slowly varying pipe. Finally, the parameter effects, including the axial distance, the slowly varying angle, and the Reynolds number, on the velocity distributions are analyzed. The results show that the increases in both the axial distance and the slowly varying angle make the axial velocity slow down. However, the radial velocity increases with the slowly varying angle, and decreases with the axial distance. There are two special positions in the distribution curves of the axial velocity and the radial velocity with different Reynolds numbers, and there are different trends on both sides of the special positions. The double perturbation strategy is applicable to such problems with the flow of a non-Newtonian fluid through a slowly varying pipe.展开更多
Using the thin film brick-wall model and WKB approximation, the entropy of the Dirac field in the non-stationary and slowly changing Reissner-Nordstrom (R-N) black hole is calculated. The result shows that the entropy...Using the thin film brick-wall model and WKB approximation, the entropy of the Dirac field in the non-stationary and slowly changing Reissner-Nordstrom (R-N) black hole is calculated. The result shows that the entropy of the R-N black hole is still proportional to its surface area if we choose proper cut-off.展开更多
The evolution of Asian summer monsoon is analyzed by means of decomposition of the atmospheric circulationinto basic current and slowly varying monsoon disturbances. It is seen that the major slowly varying disturbanc...The evolution of Asian summer monsoon is analyzed by means of decomposition of the atmospheric circulationinto basic current and slowly varying monsoon disturbances. It is seen that the major slowly varying disturbances aretwo vortical couples, one located in the indian Ocean and indian Peninsula, and another in the Northern Hemisphericwestern Pacific Ocean and the East Asia. This indicates that the Asian summer monsoon consists of two branches, theIndian monsoon and the East Asian monsoon. Moreover, the analysis shows that the evolutionary processes of thesetwo vortical couples are rather independent each other, and they all can be qualitatively interpreted by the dynamicaltheory of wave packet. The different stages of summer monsoon can be very well characterized by the location and in-tensity of the two vortical couples. Besides, in particular years there exists also some quasistationary wave train andits characteristics should be further analyzed.展开更多
The stabilization problem of systems that switch among a finite set of slowly varying linear systems with arbitrary switching frequency is discussed.It is shown that if the entries of the pointwise stabilizing feedbac...The stabilization problem of systems that switch among a finite set of slowly varying linear systems with arbitrary switching frequency is discussed.It is shown that if the entries of the pointwise stabilizing feedback gain matrix are continuously differentiable functions of the entries of the system coefficient matrices,then the closed-loop system is uniformly asymptotically stable if the rate of time variation of the system coefficient matrices is sufficiently small.展开更多
By using a weakly nonlinear and perturbation method, the generalized inhomogeneous Korteweg de Vries （KdV）- Burgers equation is derived, which governs the evolution of the amplitude of Rossby waves under the influen...By using a weakly nonlinear and perturbation method, the generalized inhomogeneous Korteweg de Vries （KdV）- Burgers equation is derived, which governs the evolution of the amplitude of Rossby waves under the influence of dissipation and slowly varying topography with time. The analysis indicates that dissipation and slowly varying topography with time are important factors in causing variation in the mass and energy of solitary waves.展开更多
In this paper we study the asymptotic expansions of the solutions for a class of second order ordinary differential equations with slowly varying coefficients. The defect of the known works on these problems is noted,...In this paper we study the asymptotic expansions of the solutions for a class of second order ordinary differential equations with slowly varying coefficients. The defect of the known works on these problems is noted, and the results in [1 - 4] are improved and extended by means of the modified method of multiple scales.展开更多
According to CAAM,during the first half year of 2014,the sales of buses have grown slowly.The production and sales of passenger vehicle amount to 274thousand units and 279 thousand units respectively,up by 2.49%and 4....According to CAAM,during the first half year of 2014,the sales of buses have grown slowly.The production and sales of passenger vehicle amount to 274thousand units and 279 thousand units respectively,up by 2.49%and 4.31%.Overall increase of bus sales According to Gasgoo,during the first haft year the sale of buses(whole vehicle)has accumulated sales of 243.1thousand units,up by 7.0%year on year.The first three months have seen展开更多
基金supported by the National Natural Science Foundation of China[grant numbers 81872701,81273040]Shanxi Scholarship Council of China[grant number 2022-113].
文摘It is estimated that chronic kidney disease(CKD)will be the fifth leading cause of death in the world by 2040[1].Early recognition and intervention for kidney damage are essential.Estimated glomerular filtration rate(eGFR)can be calculated by measuring blood creatinine to evaluate glomerular function,and urinary N-acetyl-β-δ-glucosaminidase(UNAG)level is generally recognized as a marker of renal tubular injury.Exposure to lead(Pb)and cadmium(Cd)can damage renal function,leading to a decrease in eGFR and an increase in UNAG[2].Both Pb and Cd are easily accumulated in the body and then slowly released by the kidneys and excreted.So,urinary Pb(UPb)and Cd(UCd)levels can be used as biomarkers of exposure[3,4].
基金Supported by the Natural Science Foundation of the Guangdong Education Department(200019)the Natural Science Foundation of Guangdong Province(980030).
文摘We investigate the adiabatic enhanced compression of ultrashort pulses from a distributed feedback laser operated at 1550 nm in fibres with slowly decreasing dispersion (FSDD). High-quality pulse compressions from 4.4 ps down to 1.1ps in a l00m FSDD and from 4.4ps down to 830fs in a 500m FSDD are obtained. The Raman self frequency shift of femtosecond pulses in the compression is observed. Theoretical analyses are in good agreement with experimental results.
基金supported by the National Natural Science Foundation of China(Nos.11572203 and11332006)
文摘A double perturbation strategy is presented to solve the asymptotic solutions of a Johnson-Segalman （J-S） fluid through a slowly varying pipe. First, a small parameter of the slowly varying angle is taken as the small perturbation parameter, and then the second-order asymptotic solution of the flow of a Newtonian fluid through a slowly varying pipe is obtained in the first perturbation strategy. Second, the viscoelastic parameter is selected as the small perturbation parameter in the second perturbation strategy to solve the asymptotic solution of the flow of a J-S fluid through a slowly varying pipe. Finally, the parameter effects, including the axial distance, the slowly varying angle, and the Reynolds number, on the velocity distributions are analyzed. The results show that the increases in both the axial distance and the slowly varying angle make the axial velocity slow down. However, the radial velocity increases with the slowly varying angle, and decreases with the axial distance. There are two special positions in the distribution curves of the axial velocity and the radial velocity with different Reynolds numbers, and there are different trends on both sides of the special positions. The double perturbation strategy is applicable to such problems with the flow of a non-Newtonian fluid through a slowly varying pipe.
文摘Using the thin film brick-wall model and WKB approximation, the entropy of the Dirac field in the non-stationary and slowly changing Reissner-Nordstrom (R-N) black hole is calculated. The result shows that the entropy of the R-N black hole is still proportional to its surface area if we choose proper cut-off.
文摘The evolution of Asian summer monsoon is analyzed by means of decomposition of the atmospheric circulationinto basic current and slowly varying monsoon disturbances. It is seen that the major slowly varying disturbances aretwo vortical couples, one located in the indian Ocean and indian Peninsula, and another in the Northern Hemisphericwestern Pacific Ocean and the East Asia. This indicates that the Asian summer monsoon consists of two branches, theIndian monsoon and the East Asian monsoon. Moreover, the analysis shows that the evolutionary processes of thesetwo vortical couples are rather independent each other, and they all can be qualitatively interpreted by the dynamicaltheory of wave packet. The different stages of summer monsoon can be very well characterized by the location and in-tensity of the two vortical couples. Besides, in particular years there exists also some quasistationary wave train andits characteristics should be further analyzed.
文摘The stabilization problem of systems that switch among a finite set of slowly varying linear systems with arbitrary switching frequency is discussed.It is shown that if the entries of the pointwise stabilizing feedback gain matrix are continuously differentiable functions of the entries of the system coefficient matrices,then the closed-loop system is uniformly asymptotically stable if the rate of time variation of the system coefficient matrices is sufficiently small.
基金supported by the Knowledge Innovation Key Program of the Chinese Academy of Sciences (Grant No. KZCX1-YW-12)the National Key Science Foundation of China (Grant No. 41030855)
文摘By using a weakly nonlinear and perturbation method, the generalized inhomogeneous Korteweg de Vries （KdV）- Burgers equation is derived, which governs the evolution of the amplitude of Rossby waves under the influence of dissipation and slowly varying topography with time. The analysis indicates that dissipation and slowly varying topography with time are important factors in causing variation in the mass and energy of solitary waves.
基金The Project Supported by the National Natural Science Foundation of China
文摘In this paper we study the asymptotic expansions of the solutions for a class of second order ordinary differential equations with slowly varying coefficients. The defect of the known works on these problems is noted, and the results in [1 - 4] are improved and extended by means of the modified method of multiple scales.
文摘According to CAAM,during the first half year of 2014,the sales of buses have grown slowly.The production and sales of passenger vehicle amount to 274thousand units and 279 thousand units respectively,up by 2.49%and 4.31%.Overall increase of bus sales According to Gasgoo,during the first haft year the sale of buses(whole vehicle)has accumulated sales of 243.1thousand units,up by 7.0%year on year.The first three months have seen
