| 1 | A cell-centered lagrangian scheme in two-dimensional cylindrical geometry显示文摘A new Lagrangian cell-centered scheme for two-dimensional compressible flows in planar geometry is proposed by Maire et al.The main new feature of the algorithm is that the vertex velocities and the numerical fluxes through the cell interfaces are all evaluated in a coherent manner contrary to standard approaches.In this paper the method introduced by Maire et al.is extended for the equations of Lagrangian gas dynamics in cylindrical symmetry.Two different schemes are proposed,whose difference is that one uses volume weighting and the other area weighting in the discretization of the momentum equation.In the both schemes the conservation of total energy is ensured,and the nodal solver is adopted which has the same formulation as that in Cartesian coordinates.The volume weighting scheme preserves the momentum conservation and the area-weighting scheme preserves spherical symmetry.The numerical examples demonstrate our theoretical considerations and the robustness of the new method. | SHEN ZhiJun YUAN GuangWei YUE JingYan LIU XueZhe | 2008 | Science China Mathematics2008，51，8： | 4 |
| 2 | Combination therapy of thiamine,vitamin C and hydrocortisone in treating patients with sepsis and septic shock:a meta-analysis and trial sequential analysis显示文摘Background:The objective of this study was to evaluate the clinical efficacy of thiamine and vitamin C with or without hydrocortisone coadministration on the treatment of sepsis and septic shock.Methods:MEDLINE,EMBASE and CENTRAL databases were searched for randomized controlled trials(RCTs)that made a comparative study between the combination therapy of vitamin C and thiamine with or without hydrocortisone and the administration of placebo in patients with sepsis or septic shock.Two reviewers independently performed study selection,data extraction and quality assessment.Both short-term mortality and change in the sequential organ failure assessment(SOFA)score from baseline(delta SOFA)were set as the primary outcomes.Secondary endpoints included intensive care unit(ICU)mortality,new onset of acute kidney injury,total adverse events,ICU and hospital length of stay,duration of vasopressor usage and ventilator-free days.Meanwhile,trial sequential analysis was conducted for primary outcomes.Results:Eight RCTs with 1428 patients were included in the current study.The results showed no significant reduction of short-term mortality in sepsis and septic shock patients who received combination therapy of vitamin C and thiamine with or without hydrocortisone compared to those with placebo{risk ratio(RR),1.02[95%confidence interval(CI),0.87 to 1.20],p=0.81,I2=0%;risk difference(RD),0[95%CI,−0.04 to 0.05]}.Nevertheless,the combination therapy was associated with significant reduction in SOFA score[mean difference(MD),−0.63,(95%CI,−0.96 to−0.29,p<0.001,I^(2)=0%]and vasopressors duration(MD,−22.11[95%CI,−30.46 to−13.77],p<0.001,I2=6%).Additionally,there were no statistical differences in the pooled estimate for other outcomes.Conclusions:In the current meta-analysis,the combination therapy of vitamin C and thiamine,with or without hydrocortisone had no impact on short-term mortality when compared with placebo,but was associated with significant reduction in SOFA score among patients with sepsis and septic shock. | Renqi Yao Yibing Zhu Yue Yu Zhixuan Li Lixue Wang Liyu Zheng Jingyan Li Huibin Huang Guosheng Wu Feng Zhu Zhaofan Xia Chao Ren Yongming Yao | 2021 | Burns & Trauma2021，9，1： | 2 |
| 3 | Picard-Newton Iterative Method with Time Step Control for Multimaterial Non-Equilibrium Radiation Diffusion Problem显示文摘For a new nonlinear iterative method named as Picard-Newton(P-N)iterative method for the solution of the time-dependent reaction-diffusion systems,which arise in non-equilibrium radiation diffusion applications,two time step control methods are investigated and a study of temporal accuracy of a first order time integration is presented.The non-equilibrium radiation diffusion problems with flux limiter are considered,which appends pesky complexity and nonlinearity to the diffusion coef-ficient.Numerical results are presented to demonstrate that compared with Picard method,for a desired accuracy,significant increase in solution efficiency can be obtained by Picard-Newton method with the suitable time step size selection. | Jingyan Yue Guangwei Yuan | 2011 | Communications in Computational Physics2011，10，9： | 1 |
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