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The functional properties of piezoelectric ceramic materials, such as barium titanate, are highly dependent on grain size. Lead-free polycrystalline Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) samples were prepared with a combination of the hydrothermal method and spark plasma sintering to achieve grain sizes from 100 nm to 10 μm by varying the maximum sintering temperature. In this range, a transition from a nearly linear dielectric to a ferroelectric response can be seen in macroscopic electromechanical measurements, demonstrating the importance of grain size on functional properties in BCZT. Furthermore, in situ electric field-dependent synchrotron x-ray diffraction measurements were performed to quantify the intrinsic and extrinsic strain contributions and their variations with grain size. At lower grain sizes, the data revealed a significant loss of extrinsic contributions in the piezoelectric behavior, limiting the response to intrinsic contribution associated with lattice strain. For BCZT, a critical grain size between approximately 0.08 and 0.18 μm is proposed, below which no piezoelectric response was observed. [ABSTRACT FROM AUTHOR]

Objective To evaluate the efficacy and safety of high-dose cyclophosphamide (CTX) intravenous injection combined with glucocorticoid in the treatment of idiopathic membranous nephropathy (IMN). Methods Clinical data of 78 IMN patients with manifestation of nephrotic syndrome (NS) admitted in Guangdong Provincial People's Hospital from January 2007 to June 2019 were collected and retrospectively analyzed. The patients were assigned into either intravenous CTX combined with glucocorticoid group (ICTX group, n=39), or oral CTX combined with glucocorticoid group (OCTX group, n=39). The subjects of ICTX group were treated with monthly intravenous CTX administration 0.50~0.75 g/m2+oral prednisone 0.5 mg/(kg·d) for 6 months. By contrast, those in OCTX group were given intravenous methylprednisolone 0.5 g qd×3 d+oral prednisone 0.5 mg/(kg·d)×27 d in the first, third and fifth month, respectively, and given oral CTX 2.5mg/(kg·d)+ oral prednisone 10 mg/d in the second, fourth and sixth month, respectively. Comparison was made between the 2 groups about the remission of proteinuria, serum albumin (sALB), estimated glomerular filtration rate (eGFR), recurrence rate and incidence of adverse reactions (ADR) before and 3, 6 and 12 months after the treatment. Results The total remission rate of proteinuria in ICTX group was higher than that in OCTX group at 3, 6, 12 months (50.0% vs 46.4%; 59.4% vs 50.0%; 88.9% vs 75.0%, respectively), though showed no significant differences. sALB and eGFR in both groups were significantly increased from baseline, while 24 h urinary protein (24hUP) and serum creatinine (Scr) were decreased in 3, 6, 12 months after the treatment (P < 0.05); and sALB had a more significant rise in ICTX group than OCTX group at 3 months (6.2 vs 4.8 g/L, P=0.013). After complete remission (CR) or partial remission (PR), the recurrence rates of ICTX and OCTX groups represented 8.3% and 13.0%, respectively, with no significant differences. In addition, the WBC count in the ICTX group was higher than that in the OCTX group at 3 months. Finally, a total of 9 cases of ADR occurred in the ICTX group (23.1%) and 10 cases in the OCTX group (25.6%). Conclusion The ICTX regimen significantly reduces proteinuria of IMN patients with clinical manifestation of NS, improving the remission rate of proteinuria, increasing serum albumin rapidly, and showing a low recurrence rate, good tolerance, as well as no significant increase in adverse reactions.

Nonparametric estimation of the conditional expectation E (Y | U) of an outcome Y given a covariate vector U is of primary importance in many statistical applications such as prediction and personalized medicine. In some problems, there is an additional auxiliary variable Z in the training dataset used to construct estimators, but Z is not available for future prediction or selecting patient treatment in personalized medicine. For example, in the training dataset longitudinal outcomes are observed, but only the last outcome Y is concerned in the future prediction or analysis. The longitudinal outcomes other than the last point is then the variable Z that is observed and related with both Y and U. Previous work on how to make use of Z in the estimation of E (Y | U) mainly focused on using Z in the construction of a linear function of U to reduce covariate dimension for better estimation. Using E (Y | U) = E { E (Y | U , Z) | U } , we propose a two-step estimation of inner and outer expectations, respectively, with sufficient dimension reduction for kernel estimation in both steps. The information from Z is utilized not only in dimension reduction, but also directly in the estimation. Because of the existence of different ways for dimension reduction, we construct two estimators that may improve the estimator without using Z. The improvements are shown in the convergence rate of estimators as the sample size increases to infinity as well as in the finite sample simulation performance. A real data analysis about the selection of mammography intervention is presented for illustration. [ABSTRACT FROM AUTHOR]