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Motivated by the papers of Mladenović and Piterbarg (2006), Krajka (2011), and Pereira and Tan (2017), we study the limit properties for the maxima from non stationary random fields subject to missing observations and obtain the weakly convergence and almost sure convergence results for these maxima. Some examples such as Gaussian random fields, chi-random fields, and Gaussian order statistics fields are given to illustrate the obtained results. [ABSTRACT FROM AUTHOR]

Let { Z (τ , s) , (τ , s) ∈ [ a , b ] × [ 0 , T ] } with some positive constants a, b, T be a centered Gaussian random field with variance function σ 2 (τ , s) satisfying σ 2 (τ , s) = σ 2 (τ) . We first derive the exact tail asymptotics (as u → ∞ ) for the probability that the maximum M H (T) = max (τ , s) ∈ [ a , b ] × [ 0 , T ] [ Z (τ , s) / σ (τ) ] exceeds a given level u, for any fixed 0 < a < b < ∞ and T > 0 ; and we further derive the extreme limit law for M H (T) . As applications of the main results, we derive the exact tail asymptotics and the extreme limit laws for Shepp statistics with stationary Gaussian process, fractional Brownian motion and Gaussian integrated process as inputs. [ABSTRACT FROM AUTHOR]

Variable selection and error structure determination of a partially linear model with time series errors are important issues. In this paper, we investigate the regression coefficient and autoregressive order shrinkage and selection via the smoothly clipped absolute deviation penalty for a partially linear model with a divergent number of covariates and finite order autoregressive time series errors. Both consistency and asymptotic normality of the proposed penalized estimators are derived. The oracle property of the resultant estimators is proved. Simulation studies are carried out to assess the finite‐sample performance of the proposed procedure. A real data analysis is made to illustrate the usefulness of the proposed procedure as well. [ABSTRACT FROM AUTHOR]

It is well known that dimethyl sulphoxide (DMSO) increases membrane permeability, which makes it widely used as a vehicle to facilitate drug delivery across biological membranes. However, the mechanism of how DMSO increases membrane permeability has not been well understood. Recently, molecular dynamics simulations have demonstrated that DMSO can induce water pores in biological membranes, but no direct experimental evidence is so far available to prove the simulation result. Using FluxOR Ti+ influx assay and intracellular Ca2+ imaging technique, we studied the effect of DMSO on Ti+ and Ca2+ permeation across cell membranes. Upon application of DMSO on CHO-K1 cell line, Ti+ influx was transiently increased in a dose-dependent manner. The increase in Ti+ permeability induced by DMSO was not changed in the presence of blockers for K+ channel and Na+-K+ ATPase, suggesting that Ti+ permeates through transient water pores induced by DMSO to enter into the cell. In addition, Ca2+ permeability was significantly increased upon application of DMSO, indicating that the transient water pores induced by DMSO were non-selective pores. Furthermore, similar results could be obtained from RAW264.7 macrophage cell line. Therefore, this study provided experimental evidence to support the prediction that DMSO can induce transient water pores in cell membranes, which in turn facilitates the transport of active substances across membranes. [ABSTRACT FROM AUTHOR]