FRL–FRH phase transition behavior in the stacked Pb(Zr1-xTix)O3 perovskite ceramics

Zirconium rich Pb(Zr1-xTix)O3 (PZT in abbreviation) reveals a pronounced nonlinear pyroelectric effect at the temperature induced FRL–FRH phase transition. This characteristic makes it a competitive candidate for the applications of the direct thermal-electric energy conversion and infrared detecting technology. However the narrow FRL–FRH phase transition temperature range (about 2°C around the pyroelectric peak) restricts its wide applications. A stacked multi-layer PZT ceramics made by PZT 97/3 (Zr/Ti ratio) with different Nb2O5 dopants is expected to solve this problem. In the paper the FRL–FRH phase transition behavior in a stacked three-layer PZT ceramics has been investigated. The results show that a smooth FRL–FRH phase transition can take place in a certain temperature range. The XRD interface line analysis of the distribution of Nb5+ content exhibits apparent Nb5+ ion diffusion between each two layers. The Nb5+ ion diffusion has significant effects on the behavior of the output pyroelectric current. A simple experiment has been explored to confirm this effect

Increased Plasma Dipeptidyl Peptidase-4 Activities in Patients with Coronary Artery Disease.

Dipeptidyl peptidase-4 (DPP4) is one of the most potent mammalian serine proteases participated in the pathogenesis of subclinical atherosclerosis. Here we investigated whether the plasma soluble form of DPP4 is associated with the prevalence of coronary artery disease (CAD) with and without diabetes mellitus (DM). A cross-sectional study was conducted of 496 aged 26-81 years with (n = 362) and without (n = 134) CAD. Plasma DPP4 activity, high sensitive C-reactive protein (hs-CRP), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein levels were measured. The coronary atherosclerotic plaques were evaluated by coronary angiography. The CAD patients with (n = 84) and without (n = 278) DM had significantly higher DPP4 levels (11.8 ± 3.1 vs. 6.9 ± 3.5 ng/mL, P<0.01) than the nonCAD subjects. The acute coronary syndrome patients (n = 299) had elevated DPP4 levels than those with stable angina patients (n = 83). CAD patients even without DM had increased plasma DPP4 activities as compared with nonCAD subjects (10.9 ± 4.9 vs. 6.4 ± 3.1, ng/L, P< 0.01). A linear regression analysis revealed that overall, the DPP4 levels were positively associated with LCL-C and hs-CRP levels as well as syntax scores. A multiple logistic regression analysis demonstrated that plasma DPP4 activity was independent predictor of CAD (odds ratio, 1.56; 95% CI, 1.19-1.73; P<0.01). Our study shows that increased DPP4 activity levels are associated with the presence of CAD and that the plasma DPP4 level serves as a novel biomarker for CAD even without DM

Demographic and Clinical Variables of CAD/DM(+) and CAD/DM(-).

<p>Demographic and Clinical Variables of CAD/DM(+) and CAD/DM(-).</p

Demographic and Clinical Variables of nonCAD/DM(+) and nonCAD/DM(-).

<p>Demographic and Clinical Variables of nonCAD/DM(+) and nonCAD/DM(-).</p

Independent predictors of CAD According to Multivariable Logistic Regression Analysis.

<p>Independent predictors of CAD According to Multivariable Logistic Regression Analysis.</p