wave break zone | ScienceGate

In this study, due to the inconsistencies in the understanding of the sedimentary types in the second section of the Dongying Formation (Ed2) and the third section of the Shahejie Formation (Es3) in the middle and deep strata of Nanpu No. 3 structural area, the depositional characteristics of the deep braided river delta, fan delta, deep-water slump turbidite fan, and coastal and shallow lake in the Nanpu No. 3 structural area were examined in-depth. The investigations were begun based on the descriptions and observations of core samples obtained from eight cored wells in the study area, in combination with seismic, well logging, and rock ore data. The results revealed that the sources of the material in the study area originated from the Shaleitian salient in the southwest direction. It was determined that the fan deltas and the shallow lake sedimentary system had developed during the SQ1 sequence and SQ2 sequence periods. The braided river deltas and the shallow lake and turbidite sedimentary system with multi-stage superposition had developed during the SQ3 to SQ7 sequence periods, and their distribution range had been controlled by the structural background of the gentle slope zone of the lake basin. On that basis, a sequence deposition filling model controlled by a slope break zone in the middle and deep strata of the Nanpu No. 3 structural area was established in this study starting from the typical seismic profile, in which such factors as the tectonic activity characteristics, lake basin boundary shape, water depths, and so on, were comprehensively considered. The goal of this research investigation was to provide beneficial information for oil and gas explorations in similar areas.

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Abstract 18637: Recurrence Quantification Analysis to Distinguish Active From Passive Mechanisms of CFAEs During Catheter Ablation of Atrial Fibrillation

Circulation ◽

10.1161/circ.132.suppl_3.18637 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Alex Baher ◽

Anil K Gehi ◽

Prabhat Kumar ◽

Eugene Chung ◽

Benjamin H Buck ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Recurrence Quantification Analysis ◽

Slow Conduction ◽

Recurrence Quantification ◽

Quantification Analysis ◽

Mean Cycle ◽

Recurrent Patterns ◽

Wave Break ◽

Complex Fractionated Atrial Electrograms

Background: Ablation of complex fractionated atrial electrograms (CFAEs) is controversial, primarily because of difficulty in visually distinguishing CFAEs representing an active site of driver activity from a passive site of double potentials, wave break, and/or slow conduction. We hypothesized that CFAEs within rotors in atrial fibrillation (AF) would exhibit highly recurrent behavior compared with CFAEs remote from these driver regions. Methods: Active and passive mechanisms of CFAE formation were simulated in several 2D 7.5 x 7.5 cm modified Luo-Rudy 1 models. CFAEs within areas of rotors were considered active, while those caused by wave break, slow conduction or double potentials remote from rotors were considered passive. Clinical signals were also collected during catheter ablation of paroxysmal AF (n=8 patients). An active driver CFAE site was defined by termination of AF with ablation followed by non-inducibility. A passive site was defined as CFAE occurring remotely. Detection of CFAEs was based on mean cycle length (MCL) calculated from 4 second windows using -dV/dt for detection (40ms refractory period/10ms maximum EGM width for simulations; 45ms/15ms respectively for clinical signals). Recurrence quantification analysis (RQA) was performed on discrete time series of simulated and clinical CFAE activations. Results: RQA was performed on 20 simulated EGMs. MCL was similar in both active and passive CFAEs (74±11ms and 78±6ms respectively, p=NS), but recurrence was significantly higher in active compared to passive sites (%recurrence: 61±22% active, 4±6% passive, p<0.01). In patients with AF, the driver sites were all located within the pulmonary vein antra while passive CFAEs were remote. The MCL of CFAEs at active driver sites was similar to that of passive sites (100±13ms active, 98±17ms passive, p=NS), but recurrence was significantly higher in the active driver sites (%recurrence: 18±15% active, 2±1% passive, p=0.02). Conclusion: CFAEs may occur due to either active or passive mechanisms. Sites within rotors or focal drivers of AF are more likely to exhibit recurrent patterns. RQA may be a powerful tool to differentiate driver from bystander CFAEs enabling more efficient targeting for ablation.

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Model of dynamic charge density wave break-up in an applied temperature gradient

Synthetic Metals ◽

10.1016/0379-6779(91)91693-5 ◽

1991 ◽

Vol 43 (3) ◽

pp. 3851-3854

Author(s):

P Barilla ◽

M.F Hundley ◽

W.N Creager ◽

A Zettl

Keyword(s):

Temperature Gradient ◽

Charge Density ◽

Charge Density Wave ◽

Density Wave ◽

Dynamic Charge ◽

Break Up ◽

Wave Break

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Electrophysiological heterogeneity and stability of reentry in simulated cardiac tissue

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.280.2.h535 ◽

2001 ◽

Vol 280 (2) ◽

pp. H535-H545 ◽

Cited By ~ 57

Author(s):

Fagen Xie ◽

Zhilin Qu ◽

Alan Garfinkel ◽

James N. Weiss

Keyword(s):

Action Potential ◽

Action Potential Duration ◽

Cardiac Tissue ◽

Potential Model ◽

Dynamic Instability ◽

Spatial Scales ◽

Cardiac Cells ◽

Dynamic Factors ◽

Cardiac Model ◽

Wave Break

Generation of wave break is a characteristic feature of cardiac fibrillation. In this study, we investigated how dynamic factors and fixed electrophysiological heterogeneity interact to promote wave break in simulated two-dimensional cardiac tissue, by using the Luo-Rudy (LR1) ventricular action potential model. The degree of dynamic instability of the action potential model was controlled by varying the maximal amplitude of the slow inward Ca2+ current to produce spiral waves in homogeneous tissue that were either nearly stable, meandering, hypermeandering, or in breakup regimes. Fixed electrophysiological heterogeneity was modeled by randomly varying action potential duration over different spatial scales to create dispersion of refractoriness. We found that the degree of dispersion of refractoriness required to induce wave break decreased markedly as dynamic instability of the cardiac model increased. These findings suggest that reducing the dynamic instability of cardiac cells by interventions, such as decreasing the steepness of action potential duration restitution, may still have merit as an antifibrillatory strategy.

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Mechanism of Procainamide-Induced Prevention of Spontaneous Wave Break During Ventricular Fibrillation

Circulation ◽

10.1161/01.cir.100.6.666 ◽

1999 ◽

Vol 100 (6) ◽

pp. 666-674 ◽

Cited By ~ 29

Author(s):

Young-Hoon Kim ◽

Masaaki Yashima ◽

Tsu-Juey Wu ◽

Rahul Doshi ◽

Peng-Sheng Chen ◽

...

Keyword(s):

Ventricular Fibrillation ◽

Wave Break

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Study on Slope Instability Disciplinarian on the Condition of Rainfall

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.353-356.654 ◽

2013 ◽

Vol 353-356 ◽

pp. 654-658

Author(s):

Nan Tong Zhang ◽

Xiao Chun Zhang ◽

Hua Rong Wang ◽

Chen Yan

Keyword(s):

Slope Stability ◽

Tensile Stress ◽

Rainfall Intensity ◽

Pore Water Pressure ◽

Water Pressure ◽

Road Construction ◽

Slope Instability ◽

Slope Surface ◽

Large Area ◽

Break Zone

Slope stability is one of the problems of road construction which should be faced with and solve. Rainfall can reduce the shear strength of slope soil and raise the underground water level which can lead to increase slope soil pore water pressure. The influence of rainfall infiltration on slop is mainly to change the slope seepage field, increase dynamic and hydrostatic water load on the slope soil and decrease of soil shear parameters. More abundant rainfall of typhoon area could make the road slope stability more fragile. Based on Matoushan Mountain along 104 state roads in Taizhou city, Zhejiang province, slope instability disciplinarian on the condition of rainfall is studied using the method of numerical simulation in this paper. As the results, when the rainfall intensity was 0.006 m/h and continuous rain was in 24 hours, the slope surface compressive stress tends to zero which began to appear tensile stress area on the condition of self-weight. And when the rainfall intensity was 0.01 m/h and continuous rain was in 24 hours, the large area of the slope surface was tensile stress area which means to appear break zone in slope surface and likely to landslide at the same time.

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Structural Style in Gentle Slope and its Control Action for Sedimentary and Reservoir Formation of Chenjiazhuang Area in Jiyang Depression for Case

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.187.84 ◽

2011 ◽

Vol 187 ◽

pp. 84-91

Author(s):

Zhen Feng Fan ◽

Jin Liang Zhang ◽

Xiao Lin Liu ◽

Jin Kai Wang

Keyword(s):

Large Scale ◽

Controlling Factors ◽

Control Action ◽

Jiyang Depression ◽

Gentle Slope ◽

Structural Style ◽

Break Zone ◽

Combining Methods

Haft-graben fault basin often have large-scale gentle slope, and the zone of structural style, sedimentary types and forming factor has its unique characteristics. This paper takes Chenjiazhuang area in Jiyang depression for example. By constructing, deposition and accumulation of combining methods Chenjiazhuang area can be divided into three major tectonic units, witch are upliftt zone, slope zone and structural slope-break zone. Different tectonic units develop different sedimentary and reservoir types, and the accumulation controlling factors are also larger differences.

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Numerical Simulation of Breaking Waves in a Wave Group by SPH

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.776.151 ◽

2015 ◽

Vol 776 ◽

pp. 151-156

Author(s):

Ni Nyoman Pujianiki

Keyword(s):

Surf Zone ◽

Breaking Waves ◽

Return Flow ◽

Wave Group ◽

Regular Waves ◽

Wave Groups ◽

Smoothed Particle ◽

Wave Heights ◽

Smoothed Particle Hydrodynamic ◽

Wave Break

Smoothed Particle Hydrodynamic (SPH) numerical model is used to investigate wave group effects at breaking and after breaking by comparing individual waves in a group with equivalent regular waves. Regular wave break almost at the same position and with the same wave height. Meanwhile in a wave group, the wave breaks in the variant positions and with variant wave heights. These phenomena cause the breaking point to be more scattered in a wave group rather than in regular waves. Return flow due to the breaking of wave groups appears more significant and is extended to the full depth in the surf zone rather than in regular waves. Swash oscillations of the wave group in the surf zone appear irregular. Meanwhile in regular waves, swash oscillations are almost constant.

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Abstract 1035: Analysis of the Mechanisms Responsible for the Genesis of the Complex Fractionated Atrial Electrogram During Atrial Fibrillation Using 3D Non-Contact Mapping System

Circulation ◽

10.1161/circ.118.suppl_18.s_640 ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Hiroshige Yamabe ◽

Kenji Morihisa ◽

Yasuaki Tanaka ◽

Takashi Uemura ◽

Koji Enomoto ◽

...

Keyword(s):

Atrial Fibrillation ◽

New Wave ◽

Contact Mapping ◽

Frequent Episodes ◽

Mapping System ◽

Atrial Electrogram ◽

Break Up ◽

Conduction Wave ◽

Wave Break ◽

Complex Fractionated Atrial Electrogram

Complex fractionated atrial electrogram (CFAE) region has been implicated as the substrate of atrial fibrillation (AF). However, how its electrogram morphology is generated has not been precisely evaluated. The purpose of this study was to investigate the mechanisms responsible for the genesis of the CFAE during AF. In 16 patients with paroxysmal AF, endocardial mapping of the left atrium was performed during AF using 3D non-contact mapping system (EnSite 3000). After localization of CFAE region, we examined the activation sequence of the wave during AF. Then, we compared the conduction velocity of the wave, frequency of wave break-up and wave fusion, and frequency of pivoting activation observed during AF between CFAE and non-CFAE regions. The CFAE was located in the roof (100%), anterior (50%), posterior (56%), pulmonary vein (PV) (81%), appendage (81%) and septum (81%), respectively. The area of CFAE was 13.4±5.0 cm2. During AF, 1 to 4 meandering reentrant waves with a maximum number of 2.3±0.7 were observed. The conduction velocity of the wave at the CFAE region was significantly slower than that at the non-CFAE region (0.65±0.38 vs. 2.31±0.89 m/second, p<0.0001). In addition, there were frequent episodes of pivoting conduction, wave break-up and wave fusion in the CFAE region, which were resulted in the generation of the multiple deflections of the local electrogram in the CFAE region. Thus, the frequency of the pivoting conduction (5.0±2.1 vs. 0.3±0.8 times/second, p<0.0001), wave break-up (5.5±3.8 vs. 0±0 times/second, p<0.0001) and wave fusion (6.5±5.8 vs. 3.6±3.1 times/second, p<0.05) at the CFAE region were significantly higher than those at the non-CFAE region. At the CFAE region, the wave break-up produced a new wave and the fused waves were organized into a new wave, then propagated to the next adjacent excitable region, resulted in the perpetuation of reentrant wave propagation. The multiple deflections of the electrogram at the CFAE region was generated by the slow conduction, frequent episodes of pivoting conduction, wave break-up and wave fusion. These features imply that CFAE region provide an important substrate for the perpetuation of reentrant wave propagation and maintenance of AF.

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