Purpose: Several epidemiologic studies have shown associations between air pollution and alterations in cardiac autonomic function. We hypothesized that pollution originating in different locations ...would have different associations with heart rate variability (HRV) among 512 male participants from the Normative Aging Study. Methods: Clinical data were collected during exams occurring November 14, 2000 through October 30, 2003 in Boston, MA, USA. HRV measures included: the standard deviation of normal-to-normal (NN) intervals, the square root of the mean of the squared differences between adjacent NN intervals, power in high (HF, 0.15 to 0.40 Hz) and low frequency (LF, 0.04 to 0.15 Hz), and LF/HF ratio and were Log10 transformed. Potential confounders were age, blood pressure, fasting blood glucose, smoking status, use of beta-blocker and angiotensin-converting enzyme inhibitors, room temperature, and outdoor apparent temperature matched on hour of electrocardiogram measurement for each subject. We used the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT4) model to calculate 36-hour back-trajectories at heights of 500 and 1000 meters, beginning at 9 a.m. of each exam date. Trajectory cluster analysis was used to classify the trajectories into seven clusters, with each cluster representing a different air transport regime. Results: Trajectory clusters originating to the west and south of Boston, and locally (short and slow-moving air masses) had significantly higher concentrations of PM2.5, black carbon, NO2, and SO2 than clusters originating from the north, northeast, and northwest, but ozone concentrations differed little across clusters. Adjusting for potential confounders, we found 61.4% (95% confidence interval (CI): 8.9%, 83.6%) and 61.0% (95% CI: 7.7%, 83.5%) lower HF on days with south and west trajectories, respectively, compared to northeast trajectory days at 1000 meters. LF/HF ratios on southwest, west, and northwest trajectory days were higher than on northeast trajectory days: 89.2% (95% CI: 3.8%, 244.9%), 84.5% (95% CI: 0.8%, 237.8%), and 102.8% (95% CI: 10.8%, 271.2%) higher, respectively. Other HRV indices and 500 meter trajectories showed no significant differences by source location. Discussion: This study suggests that polluted air from the south and west of Boston, where sources include vehicular traffic and coal burning power plants, affects cardiac autonomic function more strongly than that from the northeast. Though PM2.5 levels on northwest trajectory days were relatively low, the strong associations with LF/HF ratios suggest that the composition of air pollution from that area may be more toxic.
In this work, NiSi SALICIDE has been fully integrated with sub-50 nm gate length transistors and compared to its CoSi/sub 2/ counterpart. Nickel thickness has been reduced to target the CoSi/sub 2/ ...sheet resistance. It was found that NiSi layers basic lattice planes with vertical orientation are often observed inside the grains. NiSi-based CMOS transistors show the same performance as CoSi2-transistors, but nickel can also silicide very narrow poly lines whereas cobalt can not. Moreover, NiSi reduces the STI diode-leakage perimeter, but increases channel side leakage, where CoSi/sub 2/ shows a "Schottky behavior". Thus we show that nickel allow MOS transistor scaling for future technology.
Catecholamines are known to stimulate lipolysis of triglyceride stores in adipose tissue. However, the relationship of sympathoadrenal activity to serum lipid and lipoprotein concentrations remains ...uncertain. Since obesity, particularly the centripetal form, has recently been shown to be associated with increased urinary excretion of norepinephrine and decreased excretion of epinephrine, the possibility that the sympathoadrenal system is involved in the lipid abnormalities associated with the centripetal form of obesity was investigated. The relationship between 24-hour urinary catecholamine excretion and serum lipid and lipoprotein levels was examined among 615 male participants of the Normative Aging Study. Epinephrine excretion was positively correlated with the high-density lipoprotein cholesterol (HDL-C) level and the ratio of HDL-C to low-density lipoprotein cholesterol (LDL-C r = .15, P = .0002, and r = .11, P = .007, respectively) and inversely correlated with the triglyceride level (r = -.14, P = .0005). These relationships remained significant after adjusting for the effects of age, smoking, alcohol intake, adiposity, and insulin level. Epinephrine excretion was not significantly related to levels of total cholesterol or LDL-C. Norepinephrine and dopamine excretion were not significantly related to any lipid variable. These data suggest that (1) epinephrine plays an important role in regulating lipid and lipoprotein metabolism in humans, and (2) decreased adrenal medullary activity may contribute to the dyslipidemia (increased triglycerides and decreased HDL-C) commonly observed among the obese. The sympathoadrenal system therefore, along with hyperinsulinemia, may contribute to the increased cardiovascular risk associated with the insulin resistance syndrome.
In an embedded FLASH 90 nm technology, core devices behavior is modified by the thermal budget needed to process the specific FLASH dielectrics. When these steps are performed after the logic poly ...deposition, we observe two main kinds of changes: first the substrate doping is modified due to diffusion and segregation effects. Then, the poly morphology changes, this leads to larger poly grain size and gate doping change. To limit these effects and maintain the full compatibility with CMOS logic, thermal budget limitations are finally presented.
Tau protein concentration in cerebrospinal fluid was determined in 55 patients with Alzheimer's disease (AD), 18 patients with vascular dementia (VD), 19 patients with dementia caused by other ...disorders and 14 patients with major depression. Significantly (p < 0.05) elevated protein tau concentrations were found in AD patients (564.5 +/- 275.5 pg/ml) compared to all other patient groups (VD: 406.5 +/- 263.9 pg/ml; other dementia: 275.0 +/- 135.4 pg/ml; depression: 212.9 +/- 115.6 pg/ml). However, tau levels in AD patients covered a broad range (163.2 pg/ml-1200 pg/ml). AD patients with tau levels below the 25%-percentile of the distribution (among them a high percentage of patients with presenile onset) showed tau levels similar to those of the patients with late life depression. No significant correlations between tau levels and clinical variables such as severity of dementia, age, age of onset, duration of illness, and cerebral changes as assessed by volumetric magnetic resonance imaging could be demonstrated. Similarly, we could not find an influence of either APO-E genotype or psychotropic medication on the tau levels in AD patients. In accordance with other studies our results confirm elevated tau levels in AD compared to elderly not demented control subjects. Comparing groups, this finding applies as well with respect to VD and other dementing disorders. However, elevated tau levels cannot be detected in a subgroup of AD patients. This finding needs to be further investigated in future studies.
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