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This article compares acoustical quality in shoebox, nonshoebox, and surround types of concert halls based on objectively measured differences in the actual sound fields. Many concertgoers report that the average subjective sound quality in these 3 types of halls differs appreciably and that there are substantial differences from 1 seating location to another, especially in nonshoebox and surround halls. Measurement data in 5 major concert halls showed that the average sound strength versus distance from the stage attenuated about twice as much in surround halls as in shoebox halls. Special attention is given to the temporal and amplitude structure in the early part (before 200 ms) of the impulse responses measured at various seat positions in 24 well-known concert halls (12 shoebox, 7 nonshoebox, and 5 surround). In particular, reflective energy cumulative curves (RECC) are plotted. Significant frequency components are found in the 125- and 250-Hz octave band and initial 160-ms period after the direct sound arrival. This RECC curve effectively indicates the acoustical-quality spread in a hall. The RECC value at initial 160 ms and Binaural Quality Index (BQI) appear to be the most likely objective parameters to separate 3 types of halls. Based on further analysis of the 63 Hz-band energy build up curves in 11 concert halls, influences of both stage enclosure on bass sound response in the main floor and frequency imbalance in balcony seats are discussed. [ABSTRACT FROM AUTHOR]

OBJECTIVE Advanced glycation end products (AGEs) and their specific receptor, the receptor for AGEs (RAGE), play an important role in atherosclerosis. Recently, a soluble form of RAGE (sRAGE) has been identified in human serum. However, the role of sRAGE in cardiovascular disease is still controversial. There is no information on the association between simultaneous measurements of AGEs and sRAGE and vascular function. In this study, we evaluated the associations between serum levels of AGEs and sRAGE, ratio of AGEs to sRAGE, and vascular function. RESEARCH DESIGN AND METHODS We measured serum levels of AGEs and sRAGE and assessed vascular function by measurement of flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation in 110 subjects who underwent health examinations. Multivariate regression analyses were performed to identify factors associated with vascular function. RESULTS Univariate regression analysis revealed that FMD correlated with age, BMI, systolic blood pressure, diastolic blood pressure, heart rate, triglycerides, HDL cholesterol, glucose, smoking pack-years, nitroglycerine-induced vasodilation, serum levels of AGEs and sRAGE, and ratio of AGEs to sRAGE. Multivariate analysis revealed that the ratio of AGEs to sRAGE remained an independent predictor of FMD, while serum level of AGEs alone or sRAGE alone was not associated with FMD. CONCLUSIONS These findings suggest that sRAGE may have a counterregulatory mechanism that is activated to counteract the vasotoxic effect of the AGE--RAGE axis. The ratio of AGEs to sRAGE may be a new chemical biomarker of endothelial function. [ABSTRACT FROM AUTHOR]

Background Insulin resistance, as a key mediator of metabolic syndrome, is thought to be associated with pathogenesis of calcific aortic valve disease and altered left ventricular (LV) function and structure. However, in patients with aortic valve sclerosis (AVS), the association between insulin resistance and subclinical impairment of LV function is not fully elucidated. Methods We studied 57 patients (mean age 70 ± 8 years, 22 women) with asymptomatic AVS but normal LV ejection fraction in echocardiography. LV longitudinal and circumferential strain and strain rate was analyzed using two-dimensional speckle tracking echocardiography. Patients with uncontrolled hypertension and diabetes mellitus, chronic kidney disease, and concomitant coronary artery disease were excluded. They were divided into the insulinresistant group (AVS+IR, N = 28) and no insulin-resistant group (AVS-IR, N = 29) according to the median value of homeostatic model assessment index. Computed tomography scans were also performed to measure the aortic valve calcium score and the visceral adipose tissue (VAT) area. In addition, age- and sex- adjusted 28 control subjects were recruited for the comparison. Results There were no significant differences in LV ejection fraction or mass index among the groups. The AVS+IR group had a higher aortic valve calcium score (median 94 versus 21, P = 0.022) and a larger VAT area (113 ± 42 cm2 versus 77 ± 38 cm2, P = 0.001) than the AVS-IR group. Notably, LV global longitudinal strain, strain rate (SR), and early diastolic SR were significantly lower in the AVS+IR group than in the AVS-IR group and in control subjects (strain: -16.2 ± 1.6% versus -17.2 ± 1.2% and -18.9 ± 0.8%; SR: -1.18 ± 0.26 s-1 versus -1.32 ± 0.21 s-1and -1.52 ± 0.08 s-1, early diastolic SR: -1.09 ± 0.23 s-1 versus -1.23 ± 0.18 s-1and -1.35 ± 0.12 s-1, P < 0.05 for all comparison), whereas circumferential function were not significantly different. Multiple linear regression analyses revealed insulin resistance as an independent determinant of LV longitudinal strain (P = 0.017), SR (P = 0.047), and early diastolic SR (P = 0.049) regardless of LV mass index or VAT area. Conclusions Insulin resistance is a powerful independent predictor of subclinical LV dysfunction regardless of concomitant visceral obesity and LV hypertrophy. Thus, it may be a novel therapeutic target to prevent subsequent heart failure in patients with AVS. [ABSTRACT FROM AUTHOR]

Objective To determine the relationships between flow-mediated vasodilation (FMD) and cardiovascular risk factors, and to evaluate confounding factors for measurement of FMD in a large general population in Japan. Methods This was a cross-sectional study. A total of 5314 Japanese adults recruited from people who underwent health screening from 1 April 2010 to 31 August 2012 at 3 general hospitals in Japan. Patients' risk factors (age, Body Mass Index, blood pressure, cholesterol parameters, glucose level and HbA1c level) and prevalence of cardiovascular disease (coronary heart disease and cerebrovascular disease) were investigated. Results Univariate regression analysis revealed that FMD correlated with age (r=-0.27, p<0.001), Body Mass Index (r=-0.14, p<0.001), systolic blood pressure (r=-0.18, p<0.001), diastolic blood pressure (r=-0.13, p<0.001), total cholesterol (r=-0.07, p<0.001), triglycerides (r=-0.10, p<0.001), high-density lipoprotein cholesterol (r=0.06, p<0.001), low-density lipoprotein cholesterol (r=-0.04, p=0.01), glucose level (r=-0.14, p<0.001), HbA1c (r=-0.14, p<0.001), and baseline brachial artery diameter (r=-0.43, p<0.001) as well as Framingham Risk score (r=-0.29, p<0.001). Multivariate analysis revealed that age (t value=-9.17, p<0.001), sex (t value=9.29, p<0.001), Body Mass Index (t value=4.27, p<0.001), systolic blood pressure (t value=-2.86, p=0.004), diabetes mellitus (t value= -4.19, p<0.001), smoking (t value=-2.56, p=0.01), and baseline brachial artery diameter (t value=-29.4, p<0.001) were independent predictors of FMD. Conclusions FMD may be a marker of the grade of atherosclerosis and may be used as a surrogate marker of cardiovascular outcomes. Age, sex, Body Mass Index, systolic blood pressure, diabetes mellitus, smoking and, particularly, baseline brachial artery diameter are potential confounding factors in the measurement of FMD. [ABSTRACT FROM AUTHOR]