Propensity score is widely used to estimate treatment effects in observational *** covariate adjustment using propensity score is the most straightforward method in the literature of causal *** this article,we estimat...
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Propensity score is widely used to estimate treatment effects in observational *** covariate adjustment using propensity score is the most straightforward method in the literature of causal *** this article,we estimate the survival treatment effect with covariate adjustment using propensity score in the semiparametric accelerated failure time *** establish the asymptotic properties of the proposed estimator by simultaneous estimating *** conduct simulation studies to evaluate the finite sample performance of the proposed method.A real data set from the German Breast Cancer Study Group is analyzed to illustrate the proposed method.
Generalized case-cohort design has been proved to be a cost-effective way to enhance the efficiency of large epidemiological cohort. In this article, we propose an inference procedure for estimating the unknown parame...
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Generalized case-cohort design has been proved to be a cost-effective way to enhance the efficiency of large epidemiological cohort. In this article, we propose an inference procedure for estimating the unknown parameters in Cox＇s proportional hazards model in generalized case-cohort design and establish an optimal sample size allocation to achieve the maximum power at a given budget. The finite sample performance of the proposed method is evaluated through simulation studies. The proposed method is applied to a real data set from the National Wilm＇s Tumor Study Group.
The minimax concave penalty （MCP） has been demonstrated theoretically and practical- ly to be effective in nonconvex penalization for variable selection and parameter estimation. In this paper, we develop an efficie...
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The minimax concave penalty （MCP） has been demonstrated theoretically and practical- ly to be effective in nonconvex penalization for variable selection and parameter estimation. In this paper, we develop an efficient alternating direction method of multipliers （ADMM） with continuation algorithm for solving the MCP-penalized least squares problem in high dimensions. Under some mild conditions, we study the convergence properties and the Karush-Kuhn-Tucker （KKT） optimality con- ditions of the proposed method. A high-dimensional BIC is developed to select the optimal tuning parameters. Simulations and a real data example are presented to illustrate the efficiency and accuracy of the proposed method.
The smooth integration of counting and absolute deviation （SICA） penalized variable selection procedure for high-dimensional linear regression models is proposed by Lv and Fan （2009）. In this article, we extend th...
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The smooth integration of counting and absolute deviation （SICA） penalized variable selection procedure for high-dimensional linear regression models is proposed by Lv and Fan （2009）. In this article, we extend their idea to Cox＇s proportional hazards （PH） model by using a penalized log partial likelihood with the SICA penalty. The number of the regression coefficients is allowed to grow with the sample size. Based on an approximation to the inverse of the Hessian matrix, the proposed method can be easily carried out with the smoothing quasi-Newton （SQN） algorithm. Under appropriate sparsity conditions, we show that the resulting estimator of the regression coefficients possesses the oracle property. We perform an extensive simulation study to compare our approach with other methods and illustrate it on a well known PBC data for predicting survival from risk factors.
The Tetrahedral Constellation Gravitational Wave Observatory(TEGO)[1]represents a significant leap forward in gravitational wave detection,advancing our understanding of gravitational *** introducing a fourth spacecra...
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The Tetrahedral Constellation Gravitational Wave Observatory(TEGO)[1]represents a significant leap forward in gravitational wave detection,advancing our understanding of gravitational *** introducing a fourth spacecraft to form a tetrahedral configuration,TEGO enhances traditional triangular setups,enabling the simultaneous sensitivity to all six gravitational wave polarization modes,including those not predicted by general relativity.
Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-met...
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Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.
Objective To investigate the therapeutic effect of Xiangshao Granules(XSG)on post-stroke depression(PSD)and explore the underlying *** Forty-three C57BL/6J mice were divided into 3 groups:sham(n=15),PSD+vehicle(n=14),...
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Objective To investigate the therapeutic effect of Xiangshao Granules(XSG)on post-stroke depression(PSD)and explore the underlying *** Forty-three C57BL/6J mice were divided into 3 groups:sham(n=15),PSD+vehicle(n=14),and PSD+XSG(n=14)groups according to a random number *** PSD models were constructed using chronic unpredictable mild stress(CUMS)after middle cerebral artery occlusion(Mcao).The sham group only experienced the same surgical operation,but without MACO and CUMS *** XSG group received XSG(60 mg/kg per day)by gavage for 4 *** mice in the sham and vehicle groups were given the same volume of 0.9%saline at the same *** body weight and behavior tests including open field test,sucrose preference test,tail suspension test,and elevated plus-maze test,were used to validate the PSD mouse ***-time fluorescence quantitative polymerase chain reaction(RT-qPCR),enzyme-linked immunosorbent assay(ELISA),and immunofluorescence staining were used to evaluate the anti-inflammatory effects of *** potential molecular mechanisms were explored and verified through network pharmacology analysis,Nissl staining,Western blot,ELISA,and RT-qPCR,*** The body weight and behavior tests showed that Mcao combined with CUMS successfully established the PSD *** alleviated neuronal damage,reduced the expressions of pro-apoptotic proteins Caspase-3 and B-cell lymphoma-2(BCL-2)-associated X(BAX),and increased the expression of anti-apoptotic protein BCL-2 in PSD mice(P<0.05 or P<0.01).XSG inhibited microglial activation and the expressions of pro-inflammatory cytokines including tumor necrosis factor-α,interleukin(IL)-1β,and IL-6 via the toll-like receptor 4/nuclear factor kappa-B signaling pathway in PSD mice(P<0.05 or P<0.01).Furthermore,XSG decreased the expression of indoleamine 2,3-dioxygenase1(IDO1)and increased the concentration of 5-hydroxytryptamine in PSD mice(P<0.05 or P<0.01).Conclusion XSG could reverse
In this study,a novel Ni-W-Co-Mo medium heavy alloy(MHA)was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-x Mo alloy series,where x represents the weight percent of Mo and varies between 0,1,2...
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In this study,a novel Ni-W-Co-Mo medium heavy alloy(MHA)was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-x Mo alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypo-eutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0 to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-x Mo alloys is Mo-induced solid solution strengthening and precipitation strengthening.
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