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Recrystallization, which is mainly caused by the induced strain, is one of the most important factors of Friction Stir Welding. In this study, strain and strain rate are directly obtained by the change in the material flow velocity which is observed by three-dimensional visualization of the material flow. The grain size of the pure aluminum in the stir zone estimated by the Zener–Hollomon parameter using the obtained strain rate shows good agreement with that observed by Electron Back-Scatter Diffraction mapping. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Deep intracerebral hematoma (ICH) is frequently associated with microbleed (MB) arising from degenerated MB. Increased numbers of MB are correlated with increased age, and we examined a possible relationship between MB number and ICH onset in younger patients. METHODS: Excluding patients with ICH and a history of ICH, we examined the number of MB and other risk factors in 195 patients with deep ICH (97 male, 98 female) consecutively admitted to our hospital. The patients were equally divided into 3 subgroups according to age (groups A, B, and C). Odds ratios were estimated from logistic regression analyses. RESULTS: The number (percentage) of MB in group A (< or =60 years old, n = 64) 5.0 +/- 9.6 (65.6%) was less than group B (61-69 years old, n = 63) 6.6 +/- 9.1 (79.4%) or group C (> or =70 years old, n = 68) 6.0 +/- 7.0 (86.8%). Multivariate analyses demonstrated that MB greater than or equal to 3 was significantly associated with higher age in group A versus B (odds ratio: 2.3; 95% confidence interval: 1.01-5.3; P = .046) and in group A versus C (odds ratio: 2.6; 95% confidence interval: 1.1-6.2; P =.030). CONCLUSIONS: Our findings suggest that risk factors for the development of ICH may differ with age, and younger patients with deep ICH have fewer MB.Copyright © 2008 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

We have fabricated ramp-edge type junctions with different high-Tc superconductor electrodes; YBa2Cu3O7−y (YBCO) and Bi2Sr2CaCu2O8+y (BSCCO). Thin films were prepared on SrTiO3 (1 0 0) substrates by a pulsed laser deposition method. YBCO was selected as a base electrode and BSCCO as a counter electrode, by considering the growth conditions for these thin films. The samples were etched by Ar ion-beam milling to pattern the shape of the ramp-edge type junction. We have prepared several junctions with and without a PrBa2Cu3O7−y barrier. In case of the junction without a barrier material, Tc''s of YBCO and BSCCO electrodes were about 90 and 60–70 K, respectively, and it was found that the maximum supercurrent between the ab planes of YBCO (RE123 superconductor) and BSCCO (Bi-based superconductor) was about 1 mA at 4.2 K. Shapiro steps were also observable. [Copyright &y& Elsevier]

Objectives: We sought to assess the effects of low density lipoprotein (LDL)-apheresis (LDL-A) for regression of coronary plaque in familial hypercholesterolemia (FH), we set up a one-year follow-up multicenter trial using coronary angiography and intravascular ultrasound (IVUS).Background: It is still unclear whether aggressive lipid-lowering therapy by LDL-A leads to the regression of coronary plaque in patients with FH.Methods: Eighteen patients with FH were assigned to one of two groups: medication + LDL-A (LDL-A group, n = 11) and medication only (medication group, n = 7). Total cholesterol, triglycerides, high density lipoprotein cholesterol and LDL cholesterol were measured in all subjects at the outset of treatment (baseline) and every three months thereafter. Coronary angiography and IVUS were performed at the outset and after the one-year follow-up period to measure minimal lumen diameter (MLD) by coronary angiogram and plaque area (PA) by IVUS.Results: The LDL-A group showed 28.4% reduction in total cholesterol (from 275 +/- 27 mg/dl to 197 +/- 19 mg/dl) and 34.3% reduction in LDL cholesterol (from 213 +/- 25 mg/dl to 140 +/- 27 mg/dl) after one-year follow-up, while the medication group showed no changes in cholesterol levels. There were significant interactions between both treatments in total cholesterol (p = 0.0001), LDL cholesterol (p = 0.0001), MLD (p = 0.008) and PA (p = 0.017) using two-way repeated-measures analysis of variance by the SAS system (SAS Institute Inc., Cary, North Carolina). Significant differences were seen in net change in MLD (p = 0.004) and PA (p = 0.008) during the one-year follow-up period between both groups.Conclusions: These results suggest that aggressive lipid-lowering therapy using the combination of LDL-A and lipid-lowering drugs may induce regression of coronary atherosclerotic plaque in FH patients. [ABSTRACT FROM AUTHOR]

Objectives: We investigated factors for carotid artery inflammation by [(18)F]-fluorodeoxyglucose (FDG) positron emission tomography (PET). Background: Inflammation is present in some atherosclerotic plaques. The FDG-PET is capable of identifying and quantifying vascular inflammation within atherosclerotic plaques. Methods: The FDG-PET imaging was performed in 216 consecutive patients (63 +/- 9 years, men:women 147:69) for cancer screening. Vascular inflammation in carotid atherosclerosis was quantified by measuring the standardized uptake value (SUV) of FDG into the artery. Results: Multiple stepwise regression analysis revealed significant relationships between SUV and waist circumference (p < 0.001), hypertensive medication (p < 0.001), carotid intima-media thickness (p < 0.001), high-density lipoprotein cholesterol (p < 0.01, inversely), homeostasis model assessment of insulin resistance (p < 0.05), or high sensitivity C-reactive protein (p < 0.05). Age- and gender-adjusted SUV of FDG was significantly higher (p < 0.0001) in proportion to the accumulation of the number of the components of the metabolic syndrome. Thus, the metabolic syndrome was associated with increased FDG uptake in carotid atherosclerosis. Conclusions: Our present study may suggest that the metabolic syndrome is associated with inflammation in carotid atherosclerosis. (Detection of Plaque Inflammation by Positron Emission Tomography (PET); http://www.clinicaltrials.gov/ct/show/NCT00114504; NCT00114504). [ABSTRACT FROM AUTHOR]

Patients with hypertrophic cardiomyopathy (HC) die suddenly. Proposed risk factors for sudden cardiac death (SCD) in HC are youth, a family history of SCD, syncope, and ventricular tachycardia. Hemodynamic variables have not convincingly proved to be risk factors for SCD. Therefore, this study was designed to examine predictors of SCD in a large number of patients with HC during long-term follow-up periods. The relation of studied variables (clinical, electrocardiographic, echocardiographic, hemodynamic, and exercise test findings) to SCD in 309 patients with HC who were initially diagnosed during 1971 through 1994 (mean follow-up 9.4 years) was examined by multivariate analysis. SCD occurred in 28 patients. Independent predictors of SCD were a smaller difference between peak and rest systolic blood pressure during exercise testing (p=0.006), and higher left ventricular outflow tract pressure gradient at rest (p=0.003). Exercise-related SCD occurred in 8 patients and exercise-unrelated SCD in 20 patients (mean age 28 vs 47 years, p <0.05). Thus, patients of exercise-related SCD were younger and had smaller increases in systolic blood pressure during exercise testing, whereas patients with exercise-unrelated SCD were older and had higher left ventricular outflow tract pressure gradient. [ABSTRACT FROM AUTHOR]