Variability in the Period of Velocity Pulse Based on Nucleation Position on the Fault

2021 ◽  
pp. 213-222
Author(s):  
K. S. K. Karthik Reddy ◽  
Surendra Nadh Somala
Keyword(s):  
Velocity Pulse

scholarly journals Comparison of 24-Hour Ambulatory Central Blood Pressure Reduction Efficacy Between Fixed Amlodipine or Up-Titrated Hydrochlorothiazide Plus Losartan: The K-Central Study

2019 ◽  
Vol 32 (10) ◽  
pp. 992-1002
Author(s):  
Eun Joo Cho ◽  
Hae Young Lee ◽  
Ki Chul Sung ◽  
Sungha Park ◽  
Il-Suk Sohn ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Wave Reflection ◽  
Pulse Wave ◽  
Blood Pressure Reduction ◽  
Multicenter Trial ◽  
Aortic Pulse Wave Velocity ◽  
Fixed Dose ◽  
Central Hemodynamics ◽  
Velocity Pulse ◽  
Double Blind

Abstract OBJECTIVE The main objective of this study was to evaluate non-inferiority of office mean systolic blood pressure (BP) reduction efficacy and superiority of 24-hour ambulatory central BP reduction efficacy between losartan combined with fixed dose amlodipine (L/A group) and dose up-titrated hydrochlorothiazide (L/H group) according to office BP. METHODS We conducted a prospective, randomized, double-blind multicenter trial in 231 patients with hypertensive (mean age = 59.2 ± 12.2 years). Patients received losartan 50 mg monotherapy for 4 weeks, followed by additional use of amlodipine 5 mg or hydrochlorothiazide 12.5 mg for 20 weeks after randomization. The patients who did not achieve the BP goal after 4 weeks’ randomization received an increased dose of 100 mg/5 mg for the L/A group and 100 mg/25 mg for L/H group, respectively. The 24-hour ambulatory central BP was measured at baseline and after 20 weeks’ treatment. RESULTS Office mean systolic BP reduction of L/A group was not inferior to L/H group after 4 weeks’ treatment (–17.6 ± 13.3 vs. –14.4 ± 12.6 mm Hg, P = 0.0863) and was not significantly different after 20 weeks’ treatment. (–15.7 ± 14.0 vs. –14.7 ± 15.1 mm Hg, P = 0.6130) The 24-hour ambulatory central systolic BP was significantly more reduced in the L/A group compared with that in the L/H group after 20 weeks’ treatment (–9.37 ± 10.67 vs. –6.28 ± 10.50 mm Hg, P = 0.0407). The 24-hour ambulatory central systolic BP at the completion of the study and its reduction magnitude were independently associated with reductions in aortic pulse wave velocity, pulse pressure, and wave reflection magnitude. CONCLUSION Office systolic BP reduction with L/A was not inferior to L/H after 4 week’s treatment. The combination of losartan and amlodipine was more favorable in 24-hour ambulatory central hemodynamics beyond BP-lowering efficacy than the combination of losartan and hydrochlorothiazide, regardless of office BP. CLINICAL TRIALS REGISTRATION NCT02294539

Conditional Ground-Motion Model for Damaging Characteristics of Near-Fault Ground Motions Based on Instantaneous Power

2020 ◽  
Vol 110 (6) ◽  
pp. 2828-2842
Author(s):  
Esra Zengin ◽  
Norman Abrahamson
Keyword(s):  
Ground Motion ◽  
Ground Motions ◽  
Accurate Estimation ◽  
Spectral Acceleration ◽  
Motion Model ◽  
Velocity Pulse ◽  
Near Fault ◽  
Instantaneous Power ◽  
Ground Motion Model ◽  
Short Time

ABSTRACT The velocity pulse in near-fault ground motions has been used as a key characteristic of damaging ground motions. Characterization of the velocity pulse involves three parameters: presence of the pulse, period of the pulse, and amplitude of the pulse. The basic concept behind the velocity pulse is that a large amount of seismic energy is packed into a short time, leading to larger demands on the structure. An intensity measure for near-fault ground motions, which is a direct measure of the amount of energy arriving in short time, called instantaneous power (IP (T1)), is defined as the maximum power of the bandpass-filtered velocity time series measured over a time interval of 0.5T1, in which T1 is the fundamental period of the structure. The records are bandpass filtered in the period band (0.2T1−3T1) to remove the frequencies that are not expected to excite the structure. Zengin and Abrahamson (2020) showed that the drift is better correlated with the IP (T1) than with the velocity pulse parameters for records scaled to the same spectral acceleration at T1. A conditional ground-motion model (GMM) for the IP is developed based on the 5%-damped spectral acceleration at T1, the earthquake magnitude, and the rupture distance. This conditional GMM can be used for record selection for near-fault ground motions that captures the key features of velocity pulses and can lead to a better representation of the median and variability of the maximum interstory drift. The conditional GMM can also be used in a vector hazard analysis for spectral acceleration (T1) and IP (T1) that can be used for more accurate estimation of drift hazard and seismic risk.

Blood velocity pulse quantification in the human conjunctival pre-capillary arterioles

2010 ◽  
Vol 80 (2) ◽  
pp. 202-208 ◽  
Author(s):  
Aristotle G. Koutsiaris ◽  
Sophia V. Tachmitzi ◽  
Periklis Papavasileiou ◽  
Nick Batis ◽  
Maria G. Kotoula ◽  
...  
Keyword(s):  
Blood Velocity ◽  
Velocity Pulse

Velocity pulse measurements in the mesenteric arterioles of rabbits

2003 ◽  
Vol 25 (1) ◽  
pp. 15-25 ◽  
Author(s):  
Aristotle G Koutsiaris ◽  
Aphroditi Pogiatzi
Keyword(s):  
Velocity Pulse ◽  
Pulse Measurements

Shear Resistant Behavior of RC Columns Subjected to Axial Pulse-Like Ground Motions

2013 ◽  
Vol 639-640 ◽  
pp. 832-835
Author(s):  
Wei Feng Zhao ◽  
Xiao Quan Hu ◽  
Qin Chen
Keyword(s):  
Axial Velocity ◽  
Ground Motions ◽  
Time History ◽  
Load Ratio ◽  
Spectral Ratio ◽  
Shear Capacity ◽  
Velocity Pulse ◽  
Rc Columns ◽  
Shear Span ◽  
Earthquake Records

The shear-resistant behavior of reinforced concrete (RC) columns subjected to axial velocity pulse-like ground motions was studied. Single RC columns with the constant vertical and horizontal fundamental period were used to investigate the influences of fault-distance of earthquake records, vertical to horizontal acceleration spectral ratio of earthquake records, initial axial load ratio and shear span ratio of RC column, on the shear-resistant behavior of RC columns. a suite of 18 strong ground motion records from Chi-chi earthquake divided into three fault-distance groups were taken as excitations to execute nonlinear dynamic time history analysis. The results demonstrated that axial velocity pulse-like earthquake action (fault-distance) had significant influences on the shear resistant-resistant of RC columns. Shear-resistant behavior (shear capacity/shear demand) increases with the increasing of fault-distance. Fault-distance and shear span ratio had a certain coupling influences on the shear-resistant behavior of RC columns.

P3573Different contribution of sympathetic nerve activity to pulse wave velocity and arterial velocity pulse index in healthy subjects

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
H Sugimoto ◽  
H Murai ◽  
T Hamaoka ◽  
Y Mukai ◽  
O Inoue ◽  
...  
Keyword(s):  
Pulse Wave Velocity ◽  
Wave Velocity ◽  
Sympathetic Nerve ◽  
Healthy Subjects ◽  
Sympathetic Nerve Activity ◽  
Pulse Wave ◽  
Velocity Pulse ◽  
Nerve Activity ◽  
Reflected Wave ◽  
The Relationship

Abstract Background Pulse Wave Velocity (PWV) is associated with the net effect of arterial stiffness and sympathetic nerve activity. Recent study demonstrated the significant relationship between PWV and muscle sympathetic nerve activity (MSNA). Arterial Velocity pulse Index (AVI) is a newly developed parameter, which could evaluate vascular reflected wave, regardless of aortic form. Vascular reflected wave is considered to be associated with sympathetic nerve activity, however little is known about the relationship between AVI and MSNA. Purpose The purpose of this study was to evaluate the relationship between AVI or PWV and MSNA in healthy subject. Method 21 healthy subjects were included in this study. AVI was measured by NAS-1000 (Nihon Koden, Japan), calculated from the time series of occlusive cuff pressure in the left upper arm. Brachial-ankle PWV (baPWV) was measured by BP-203RPEIII (Omron Healthcare, Japan). MSNA was recorded from left peroneal nerve by microneurography using tungsten microelectrode. All measurements were performed in the same day morning. Results The mean age was 31+5 years and body mass index (BMI) 22.5+3.0 kg/m2. In regression analysis, baPWV was significantly associated with age (r=0.64 P<0.05) but not with MSNA or BMI. AVI was significantly associated with MSNA (r=0.73, P<0.05) but not with age and BMI. Conclusion We found that different contribution of MSNA to baPWV and AVI and revealed that AVI was associated with MSNA in healthy subjects. These results suggest that AVI could reflect sympathetic nerve activity compared to baPWV.

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