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11.
The aim of this study was to assess the effect of menopause on circadian profile of blood pressure (BP) and heart rate (HR) in the normotensive pre- and postmenopausal women. Systolic BP (SBP), diagnostic BP (DBP) and HR were monitored every 30 min for 48 hrs using noninvasive ambulatory BP monitoring in 24 premenopausal and 40 postmenopausal women. Mean 48-hours, daytime (awake), and nighttime (sleeping) SBP, DBP and HR values were analyzed by reviewing the patients' diaries, and the nocturnal reduction rate (NRR) of SBP, DBP and HR were calculated according to the following formula. NRR (%9 = [(daytime mean-nighttime mean)/daytime mean] x 100. The study subjects were then divided into two groups according to the presence (dipper) or absence (nondipper) of a significant reduction in nocturnal BP (> 10%). Mean SBP, DBP and HR measured over 48 hours were similar between the premenopausal and the postmenopausal group. The NRR of DBP and HR in the postmenopausal group were significantly smaller than those in the premenopausal group (17.1 +/- 6.0% vs. 13.5 +/- 7.0%, 241.1 +/- 6.0% vs. 19.8 +/- 9.0%: p < 0.05). There tended to be higher prevalence of nondipper in the postmenopausal (37%) than in the premenopausal group (29%).  相似文献   
12.
A 3-D (R, θ, Z) neutronic model for the Miniature Neutron Source Reactor (MNSR) was developed earlier to conduct the reactor neutronic analysis. The group constants for all the reactor components were generated using the WIMSD4 code. The reactor excess reactivity and the four group neutron flux distributions were calculated using the CITATION code. This model is used in this paper to calculate the pointwise four energy group neutron flux distributions in the MNSR versus the radius, angle and reactor axial directions. Good agreement is noticed between the measured and the calculated thermal neutron flux in the inner and the outer irradiation sites with relative differences less than 7% and 5%, respectively.  相似文献   
13.
During the 1968 and 1969 lightning seasons, member companies of the Telephone Association of Canada conducted a field investigation of lightning voltages induced in outside plant toll facilities at ten selected sites across Canada. Oscillograms of longitudinal surge voltages occurring in open wire, paired, and coaxial cable were continuously photographed with an automatic camera system especially developed for the investigation during each season. On completion, approximately 10 000 useful surge photographs were obtained and analyzed. The results indicate that a standard test wave, with 1000-V peak and10 times 1000-mus waveshape, simulates 99.8 percent of the lightning surges encountered in paired and coaxial cables. For open wire circuits, a more suitable test wave with 2000-V peak amplitude and4 times 200-mus waveshape is required to simulate 99.8 percent of the lightning surges. The number of surges per storm was found to be far higher than previously assumed. The highest recorded incidence during a storm was 484 surges greater than 10 V. Surge repetition intervals were short in all three types of facility; about 15 percent were less than 2 s. The surge information presented provides fundamental data on lightning surge effects in Canadian telephone plants which were previously unavailable. The assembled data will be of value to the protection engineer when designing future protection systems, and also to the transmission engineer concerned with noise problems.  相似文献   
14.
Journal of Materials Science: Materials in Electronics - Single lead-free Na0.73Bi0.09(Nb1???xTax)O3 (x?=?0, 0.10, 0.20, 0.30, and 0.40) ceramic phases were processed...  相似文献   
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16.
The Co-doped bilayered LaSr2Mn2O7 manganite at low Co concentrations (0–0.15) was synthesized by the sol–gel process. The X-ray diffraction (XRD) technique confirms phase formation for all the samples under investigation. The results of ac magnetic susceptibility measurements indicate the effect of Co doping on the magnetic ordering phases. The indications of charge ordering (CO) transitions were observed in all the prepared compounds. The CO magnetic phase transition temperature was observed systematically shift to lower temperatures as the Co concentration increases. There was an anomalous oscillating magnetic behavior in all samples with a few peaks before the CO temperature in the paramagnetic (PM) region so that with an increasing Co doping, the number of peaks and amplitude were decreased. Also, the ac susceptibility measurements were performed in the presence of an applied dc magnetic field to further study of this oscillating behavior.  相似文献   
17.
It was shown that the aqueous solubility of acetaminophen in the presence of polyvinylpyrrolidone (PVP) increased. The solubility at 25°C increased from 14.3 mg mL-1 in the absence of PVP, to 19.7 mg mL-1 in the presence of 4% w/v PVP, and to 26.7 mg mL-1 in the presence of 8% w/v PVP. Dialysis studies indicated that there is a potential of binding between PVP and acetaminophen in their aqueous solutions. Dialysis studies also revealed that the nature of interaction between PVP and acetaminophen is physical and reversible, and there was no strong binding between PVP and acetaminophen in their solutions. Infrared spectroscopy of acetaminophen/PVP solid dispersion indicated that the mechanism of interaction between PVP and acetaminophen is via hydrogen bonding. Therefore, the increase in solubility of acetaminophen in the presence of PVP is probably attributed to its ability to form a water-soluble complex with PVP.  相似文献   
18.
Multimedia Tools and Applications - The natural population-based prediction of type 2 diabetes is costly since it needs a high number of resources. Even though much research has used machine...  相似文献   
19.
Multimedia Tools and Applications - Deep learning (DL) is a type of machine learning capable of processing large quantities of data to provide analytic results based on a particular...  相似文献   
20.
    
To investigate the effect of polyphenolic-rich seaweed extract (Ecklonia cava) on postprandial blood glucose (PPBG) and postprandial insulin level (PPIL) as well as investigating any associated side effects related to the study intervention in 20 prediabetic patients in Saudi Arabia. The double-blind, randomized-controlled trial was conducted from November 2020 to April 2021 in Riyadh, in 20 prediabetic patients with no other health complications. Subjects were given 600 mg of seaweed extract in a single dose for acute effect investigation. PPBG and PPIL were measured immediately at intervals of 30, 60, 90, and 120 min following 75 g of carbohydrate consumption, iAUC and peak concentration were calculated accordingly. Insignificant differences were shown for PPBG levels between study groups at intervals of 30 and 60 min (p > .05). However, PPBG results were significantly lower in the intervention group compared to placebo of 90 and 120 min after carbohydrate (75 g) consumption. The mean (SD) of PPBG in the seaweed group at 90 and 120 min was 108.1 (±8.9) and 101.3 (±8.7), respectively, compared to the placebo group at 90 and 120 min with a mean of 122.2 (±16.9) and 112.9 (±12.1), respectively (p value at 90 min = 0.032) and (p value at 120 min = 0.024). iAUC of PPBG shows no significant differences between the study groups (p > .05). There was no significant difference in PPIL between study groups at all study measurements (p > .05). Discomfort symptoms were similar between study groups (p > .05). This study indicated that a single dose of 600 mg of E. cava extract has a lowering effect on postprandial blood glucose with no associated side effects. Further research should investigate the glycemic modulating effects of marine algal extracts in the long-term investigation.  相似文献   
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