The identity of TH2 memory cells and the mechanism regulating their maintenance during allergic inflammation remain elusive. We report that circulated human CD4+ T cells expressing the prostaglandin D2 receptor (CRTH2) are TH2 central memory T cells, characterized by their phenotype, TH2 cytokine production, gene-expression profile, and the ability to respond to allergens. Only dendritic cells (DCs) activated by thymic stromal lymphopoietin (TSLP) can induce a robust expansion of CRTH2+CD4+ TH2 memory cells, while maintaining their central memory phenotype and TH2 commitments. CRTH2+CD4+ TH2 memory cells activated by TSLP-DCs undergo further TH2 polarization and express cystatin A, Charcot-Leydon crystal protein, and prostaglandin D2 synthase, implying their broader roles in allergic inflammation. Infiltrated CRTH2+CD4+ TH2 effector memory T cells in skin lesion of atopic dermatitis were associated with activated DCs, suggesting that TSLP-DCs play important roles not only in TH2 priming, but also in the maintenance and further polarization of TH2 central memory cells in allergic diseases.

No abstract

a b s t r a c tIn this paper, a novel algorithm based on Adomian decomposition for fractional differential equations is proposed. Comparing the present method with the fractional Adams method, we use this derived computational method to find a smaller ''efficient dimension'' such that the fractional Lorenz equation is chaotic. We also apply this new method to the timefractional Burgers equation with initial and boundary value conditions. Numerical results and computer graphics show that the constructed numerical is efficient.

In magnetized plasma, the magnetic field confines the particles around the field lines. The anisotropy intensity in the viscosity and heat conduction may reach the order of 10 12 . When the boundary conditions are periodic or Neumann, the strong diffusion leads to an ill-posed limiting problem. To remove the ill-conditionedness in the highly anisotropic diffusion equations, we introduce a simple but very efficient asymptotic preserving reformulation in this paper. The key idea is that, instead of discretizing the Neumann boundary conditions locally, we replace one of the Neumann boundary condition by the integration of the original problem along the field line, the singular 1/ǫ terms can be replaced by O(1) terms after the integration, so that yields a well-posed problem. Small modifications to the original code are required and no change of coordinates nor mesh adaptation are needed. Uniform convergence with respect to the anisotropy strength 1/ǫ can be observed numerically and the condition number does not scale with the anisotropy.

In magnetized plasma, the magnetic field confines particles around field lines. The ratio between the intensity of the parallel and perpendicular viscosity or heat conduction may reach the order of 10 12 . When the magnetic fields have closed field lines and form a "magnetic island", the convergence order of most known schemes depends on the anisotropy strength. In this paper, by integration of the original differential equation along each closed field line, we introduce a simple but very efficient asymptotic preserving reformulation, which yields uniform convergence with respect to the anisotropy strength. Only slight modification to the original code is required and neither change of coordinates nor mesh adaptation is needed. Numerical examples demonstrating the performance of the new scheme are presented.

Abstract:The variational iteration method is newly used to construct various integral equations of fractional order. Some iterative schemes are proposed which fully use the method and the predictor-corrector approach. The fractional Bagley-Torvik equation is then illustrated as an example of multi-order and the results show the efficiency of the variational iteration method's new role.

No abstract

No abstract