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We conducted individual participant data meta-analysis to examine the validity of interarm blood pressure difference in simultaneous measurement as a marker to identify subjects with ankle-brachial pressure index 5 mm Hg as being associated with a significant odds ratio for the presence of ankle-brachial pressure index 15 mm Hg was associated with a significant Cox stratified adjusted hazard ratio for subsequent stroke (hazard ratio, 2.42; 95% confidence interval, 127-4.60; P

An individual participant data meta-analysis was conducted in the data of 14 673 Japanese participants without a history of cardiovascular disease (CVD) to examine the association of the brachial-ankle pulse wave velocity (baPWV) with the risk of development of CVD. During the average 6.4-year follow-up period, 687 participants died and 735 developed cardiovascular events. A higher baPWV was significantly associated with a higher risk of CVD, even after adjustments for conventional risk factors (P for trend

Background: The optimal cutoff values of the brachial-ankle pulse wave velocity (baPWV) for predicting cardiovascular disease (CVD) were examined in patients with hypertension. Methods and Results: A total of 7,656 participants were followed prospectively. The hazard ratio for the development of CVD increased significantly as the baPWV increased, independent of conventional risk factors. The receiver-operating characteristic curve analysis showed that the optimal cutoff values for predicting CVD was 18.3 m/s. This cutoff value significantly predicted THE incidence of CVD. Conclusions: The present analysis suggests that the optimal cutoff value for CVD in patients with hypertension is 18.3 m/s.

Barium titanate (BaTiO3) fine particles were prepared using the 3-step thermal decomposition method of barium titanyl oxalate under various vacuum atmospheres. In this method, the first two steps prepared BaTiO3 nanoparticles with 30 nm, and at the 3rd step, BaTiO3 nanoparticles were heat-treated at various temperature and degree of vacuum. As a result, as degree of vacuum is high, particle size of BaTiO3 fine particles decreased. Moreover, the dielectric constant of BaTiO3 fine particles was measured using the powder dielectric measurement method with slurry. The dielectric constant of these particles showed the dielectric maximum of 4,320 at 200 nm despite degree of vacuum. This result revealed that degree of vacuum during particle growth of BaTiO3 particles had no relation about dielectric constant.

Powder dielectric measurement of barium titanate (BaTiO3) fine particles from 17 to 1,000 nm revealed a maximum dielectric constant at a certain particle size. The sizes with maximum dielectric constants were strongly dependent on preparation methods. When BaTiO3 fine particles were prepared in vacuum of 10-2 torr, a dielectric maximum of 15,000 was observed at 70 nm. On the other hand, when BaTiO3 fine particles were prepared in air, a dielectric maximum of 5,000 was observed at 140 nm. Structure refinement of BaTiO3 particles using a Rietveld method revealed that all of BaTiO3 particles were composed of two parts; (a) surface cubic layer and (b) bulk tetragonal layer. Moreover, a thickness of surface cubic layer for BaTiO3 particles prepared in vacuum was much thinner than that for BaTiO3 particles prepared in air. To explain the differences, a new model on the basis of “surface relaxation” was proposed.

The powder dielectric measurement of barium titanate (BaTiO 3 ) fine particles with sizes from 17 to 1,000 nm revealed the maximum dielectric constant at a certain particle size. Moreover, the sizes with maximum dielectric constants were strongly dependent on the preparation methods. When the BaTiO 3 fine particles were prepared using the original 2-step thermal decomposition method, a dielectric constant maximum of 15,000 was observed at 70 nm particle size. On the other hand, when the BaTiO 3 fine particles were prepared using the modified 3-step thermal decomposition method, a dielectric constant maximum of 5,000 was observed at 140 nm. The former BaTiO 3 was prepared in vacuum of 10 -2 torr while the latter BaTiO 3 was prepared in air. Structure refinement of BaTiO 3 particles using a Rietveld method revealed that all of BaTiO 3 particles were always composed of two parts; (a) surface cubic layer and (b) bulk tetragonal layer. Moreover, a thickness of surface cubic layer for BaTiO 3 nanoparticles prepared in vacuum of 10 -2 torr was much thinner than that for BaTiO 3 nanoparticles prepared in air. Thus, to explain these differences, a new model on the basis of "surface relaxation" was proposed.

Barium titanate (BaTiO3) nanoparticles with various particle sizes from 17 to 1,000 nm were prepared by using the 2-step thermal decomposition method of barium titanyl oxalate under various degree of vacuum. Various characterizations revealed that these particles were impurity-free, defectfree, dense BaTiO3 nanoparticles. When the degree of vacuum was high (pressure of 150 Pa at 650 ◦C), the dielectric constant of BaTiO3 particles with a size of around 60 nm exhibited a maximum of around 15,000. On the other hand, when the degree of vacuum was low (pressure of 400 Pa at 650 ◦C), no dielectric maximum was observed. To explain this size dependence, we precisely investigated a particle structure by using synchrotron radiation. As a result, the particles were always composed of two layers, i.e., a surface cubic layer and a bulk tetragonal layer, and the thickness of the surface cubic layer decreased with increasing degree of vacuum during the preparation of BaTiO3 nanoparticles. Thus, we confirmed that the surface structure was an important factor in determining the dielectric properties of BaTiO3 nanoparticles.

The powder dielectric measurement of barium titanate (BaTiO 3 ) fine particles with sizes from 17 to 1,000 nm revealed the maximum dielectric constant at a certain particle size. Moreover, the sizes with maximum dielectric constants were strongly dependent on the preparation methods. When the BaTiO 3 fine particles were prepared using the original 2-step thermal decomposition method, a dielectric constant maximum of 15,000 was observed at 70 nm particle size. On the other hand, when the BaTiO 3 fine particles were prepared using the modified 3-step thermal decomposition method, a dielectric constant maximum of 5,000 was observed at 140 nm. The former BaTiO 3 was prepared in vacuum of 10 - 2 torr while the latter BaTiO 3 was prepared in air. Structure refinement of BaTiO 3 particles using a Rietveld method revealed that all of BaTiO 3 particles were always composed of two parts; (a) surface cubic layer and (b) bulk tetragonal layer. Moreover, a thickness of surface cubic layer for BaTiO 3 nanoparticles prepared in vacuum of 10 - 2 torr was much thinner than that for BaTiO 3 nanoparticles prepared in air. Thus, to explain these differences, a new model on the basis of "surface relaxation" was proposed.