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This study investigated the longitudinal effect of new internet usage on depressive symptoms and whether economic status modified this association. Data were from the China Health and Retirement Longitudinal Study, involving 5,259 participants who were 60 +, did not use the internet in 2015, and were followed up in 2018. Linear regression with standard errors clustered at the city level was employed. We found that new internet usage was associated with less depressive symptoms, and the association was more profound among the poor participants. It implies that bridging the digital divide requires special attention to those with disadvantaged economic status. [ABSTRACT FROM AUTHOR]

This work aimed to investigate the effects of curcumin (Cur) encapsulated in triblock copolymer nanomicelles on lncRNA GAS5 expression and NF-κB signalling pathway in ischemic stroke rats. Using polycaprolactone (PCL), polyethylene (mPEG), polyglutamic acid (PLG), and Cur as raw materials, Cur-PLG-mPEG-PCL nanoparticles were prepared. Its morphology, particle size, and Zeta potential were analyzed. Then seventy-two SD rats were randomly divided into control (Ctrl) group, model group, model + blank nanomicelles (M + BNM) group, model +80 mg/mL Cur (M + C) group, model +40 mg/mL Cur-nanomicelles (M + CNM (40 mg/mL)) group, and model +80 mg/mL Cur nanomicelle (M + CNM (80 mg/mL)) group. The results showed that mean particle size of Cur-PLG-mPEG-PCL was (148.27 ± 27.44) nm, and mean Zeta potential was (−1.97 ± 0.21) mV. The evaluation time of intelligent optimization algorithm based on Single Shot MultiBox Detector (SSD) was significantly shortened, and average EEG power spectrum of ischemic cerebral pawns was significantly lower than that of the control group at θ, α, β, and γ bands for 4h (p < 0.01). These results indicate that the computer intelligent algorithm can be used to evaluate the behaviour of rats, EEG can reflect the changes of cerebral cortical function, and Cur-PLG-mPEG-PCL can improve neurological function and degree of brain injury. [ABSTRACT FROM AUTHOR]

In this paper, we present a nonconforming immersed finite element method for solving elliptic optimal control problems with interfaces. The immersed finite element space is constructed based on the rotated-Q1 nonconforming finite elements with the integral-value degrees of freedom. The method can overcome the difficulties encountered by conforming immersed finite element method. We derive error estimates for the control, state and adjoint state in both energy and L 2 norms. Numerical results are reported to support the theoretical analysis. [ABSTRACT FROM AUTHOR]

In this article, Fourier finite volume element method is provided to solve two classes of optimal control problems governed by elliptic PDEs. In two classes of problems, both distributed control and Dirichlet boundary control are given. We obtain the optimality systems of optimal control problems by the Lagrange multiplier method. Using the polar coordinates, the Fourier discretization is used in the azimuthal direction while the finite volume element approximation is used in the radial direction. In our proposed numerical method, the trial and test function spaces are carefully chosen to get accurate approximation. We use the Fourier finite volume method to approximate the control problems, the two-dimensional optimal control problem can be reduced to a one-dimensional problem. We not only observe that the convergent order of distributed control is second order, but also the convergent order of the Dirichlet boundary control is second order. Some numerical experiments are presented to illustrate accuracy and efficiency of our method. [ABSTRACT FROM AUTHOR]

In this article, two-grid methods are studied for solving nonlinear Sobolev equation using the finite volume element method. The methods are based on one coarse grid space and one fine grid space. The nonsymmetric and nonlinear iterations are only executed on the coarse grid (with grid sizeH), and the fine grid solution (with grid sizeh) can be obtained in a single symmetric and linear step. The optimalH1error estimates are presented for the proposed methods, which show that the two-grid methods achieve optimal approximation as long as the mesh sizes satisfyh= 𝒪(H3|ln H|). As a result, solving such a large class of nonlinear Sobolev equations will not be much more difficult than solving one linearized equation. [ABSTRACT FROM PUBLISHER]

Pulmonary drug delivery has become a promising route in the treatment of lung diseases because of better local retention and lower systemic penetration. In this study, etoposide-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres were designed with potential pulmonary delivery properties. The microspheres were prepared via improved emulsion-solvent evaporation method. Physicochemical characteristics, micromeritics properties and in vitro drug release behavior of the microspheres were then evaluated. Results showed that etoposide-loaded PLGA microspheres were spherical in shape with smooth surface with size (11.8 ± 1.25) μm. Particles remained stable without any changing in size and morphology after dried by the freeze-drying method. Etoposide was loaded into PLGA microspheres in an amorphous state with high drug loading ((7.7 ± 0.3)%) and encapsulation efficiency ((84.2 ± 2.9)%). Results of micromeritics properties also demonstrated that etoposide-loaded PLGA microspheres were very suitable for pulmonary delivery. In addition, in vitro drug release study indicated a sustained release profile fitted with the Ritger-Peppas equation for up to 20 days. In conclusion, the etoposide-loaded PLGA microspheres were promising for pulmonary delivery, and etoposide could be sustained released from the PLGA microspheres. [ABSTRACT FROM AUTHOR]

In this paper, we design high-order upwind finite volume element method (UFVEM) schemes to solve first-order hyperbolic partial differential-difference equation with shift, which arises in the modelling of neuronal firing. Error analysis for the schemes shows that the approximate solution obtained from UFVEM schemes isin theL2norm. Numerical examples are also provided to support the method and the theoretical analysis. The new schemes preserve the height of neuronal impulses better than usual Lax–Friedrichs schemes which we have shown in numerical examples. In addition, the numerical oscillation produced by implicit centre finite difference schemes can also be eliminated. [ABSTRACT FROM AUTHOR]

In this article, a characteristic finite volume element method is presented for solving air pollution models. The convection term is discretized using the characteristic method and diffusion term is approximated by finite volume element method. Compared with standard finite volume element method, our proposed method is more accurate and efficient, especially suitable to solve convection-dominated problems. The proposed numerical schemes are analyzed for convergence inL2norm. Some numerical results are presented to demonstrate the efficiency and accuracy of the method. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the joint tissue distribution and pharmacodynamics of Lornoxicam (Lnxc) following intra-articular injection of either Lnxc suspensions or sustained release Lnxc-loaded PLGA microspheres (Lnxc-MS), as well as the biocompatibility of PLGA microspheres with or without drugs. In this study, Lnxc suspensions or Lnxc-loaded PLGA microspheres was injected into the knee joint cavity of rats. Blood samples were taken at predetermined times from the jugular vein and the joint tissue (cartilage and synovial membrane) were removed from the rats. Biocompatibility and pharmacodynamics were evaluated by observing the swelling of the joints of the rats and histological analysis following the injection of the microspheres. The plasma drug concentration decreased in rats and retention time increased in rats' joint with intra-articular injections of microspheres, revealing good targeting efficiency and decreased systemic toxicity. After 30 days of intra-articular injection with Lnxc-loaded or blank microspheres, the filtration liquid accumulation, blood vessels and fibrous proliferation were not detected, showing their good compatibility. Furthermore, the articular cartilage damage by papain could also be repaired by the Lnxc-loaded PLGA microspheres. In conclusion, intra-articular Lnxc-MS have considerable potential for creating a sustained release Lnxc delivery system and providing effective healing to Osteoarthritis. [ABSTRACT FROM AUTHOR]

Owing to its rationale of targeting the drug to the site of action and minimizing systemic toxic effects of the drug, intra-articular drug delivery system has gained growing interests. In this study, emphasis was placed on intra-articular Lornoxicam -loaded PLGA microspheres (Lnxc-PLGA-MS) preparation and improving the targeting of lornoxicam (Lnxc) in knee joint. The microspheres were prepared by a process involving solid-in-oil-in-water(S/O/W) emulsion, and evaluated for physicochemical properties. Joint cavity′s drug leakage into systemic circulation in rabbits was examined to define the drug stagnation. Meanwhile, drug retention in synovial fluid in rats was investigated to further validate the drug targeting. The microspheres were spherical as evidenced by the SEM photographs with mean size of 7.47μm, and encapsulation efficiency was observed 82.22% along with drug loading 12.17%. DSC revealed that the drug in the microspheres existed in the phase of uncrystallization. The formulated microspheres could prolong the drug release up to 32 days in vitro. Comparing with animals injected with lornoxicam solution, the plasma drug concentration decreased in rabbits and retention time increased in rats' synovial fluid with intra-articular injections of microspheres, revealing good targeting efficiency. In conclusion, PLGA microspheres could be used to deliver lornoxicam following intra-articular administration for enhancing targeting efficiency. [ABSTRACT FROM AUTHOR]

In this paper, we propose a characteristic centred finite difference method on non-uniform grids to solve the problem of the air pollution model. Numerical solutions and error estimates of the air pollution concentration and its first-order derivatives for space variables are obtained. The computational cost of the method is the same as that of the characteristic difference method based on a linear interpolation. The error order of the numerical solutions is the same as that of the characteristic difference method based on a quadratic interpolation. At last, we give numerical examples to illustrate feasibility and efficiency of this method. [ABSTRACT FROM AUTHOR]

In this article, we use the quadratic finite volume element method (FVEM) to solve the problem of the air pollution model, choose the trial function spaces as the Lagrange quadratic element function spaces and the test function spaces as the piecewise constant function spaces, then get the error estimates of L2 and H1. Finally, by numerical experiments, we analyse and compare the FVEM with the finite difference method, and the numerical results we get show that the FVEM is much better and more effective, so this article has some practical significance in the improvement and control of air pollution. [ABSTRACT FROM AUTHOR]

A new alternating group explicit method for solving convection dominated diffusion problem of variable coefficient is presented, and the energy method is used to prove the stability of the method. [ABSTRACT FROM AUTHOR]