Computer modelling of Abdominal Aortic Aneurysms to predict the risk of rupture — the role of porosity of the thrombosis

In order to fully understand the interaction between the Abdominal Aortic Aneurysms (AAAs) and the arterial bifurcations interface it is important to attain more detailed information on blood hemodynamics stresses by using an accurate and real model of the vascular system of the human. In this study, a computer simulation, which integrates dinically acquired of 73-year-old male patient with saccular AAA MR angiograms image is considered. The numerical predictions for 2D of two models (with and without saccular AAA) – axisymmetric, rigid wall Newtonian and non-Newtonian Carreau blood model are presented. The finite volume method performed by ANSYS-Fluent Package was used to model this problem. The blood hemodynamics is considered as steady state condition in two values of Reynolds numbers of laminar flow condition. Blood hemodynamics is calculated for an improved set of dimensionless values pointer parameters include the pressure dimensionless, dimensionless Wall Shear Stress (WSS) and flow velocity. The results show that at the turbulent flow, velocity is with highest fluctuation profile and generate some vortices near the inner wall of AAA. The highest WSS levels are obtained downstream of AAA and at bifurcation apex. The presence of AAA in flow path will increase blood velocity of the distal by 35% for laminar and about 42% for turbulent. Finally, the velocity profile was compared with previous literature and give good agreement at the same computational condition.

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of Interaction between Saccular Abdominal Aortic Aneurysms and Arterial Bifurcations

Jehhef¹,

Ali²

2021

Section: Introductionmentioning

confidence: 99%

Parallel Distributed Framework for State Space Adaptive Filter for Removal of PLI from Cardiac Signals

Rehman¹,

Raza²,

Razzaq³

2021

Cardiac signals are often corrupted by artefacts like power line interference (PLI) which may mislead the cardiologists to correctly diagnose the critical cardiac diseases. The cardiac signals like high resolution electrocardiogram (HRECG), ultra-high frequency ECG (UHF-ECG) and intracardiac electrograms are the specialized techniques in which higher frequency component of interest up to 1 KHz are observed. Therefore, a state space recursive least square (SSRLS) adaptive algorithm is applied for the removal of PLI and its harmonics. The SSRLS algorithm is an effective approach which extracts the desired cardiac signals from the observed signal without any need of reference signal. However, SSRLS is inherited computational heavy algorithm; therefore, filtration of increased number of PLI harmonics bestow an adverse impact on the execution time of the algorithm. In this paper, a parallel distributed SSRLS (PD-SSRLS) algorithm is introduced which runs the computationally expensive SSRLS adaptive algorithm parallely. The proposed architecture efficiently removes the PLI along with its harmonics even the time alignment among the contributing nodes is not the same. Furthermore, the proposed PD-SSRLS scheme provides less computational cost as compared to sequentially operated SSRLS algorithm. A comparison has been drawn between the proposed PD-SSRLS algorithm and sequentially operated SSRLS algorithm in term of qualitative and quantitative performances. The simulation results show that the proposed PD-SSRLS architecture provides almost same qualitative and quantitative performances than that of sequentially operated SSRLS algorithm with less computational cost.

Section: Introductionmentioning

confidence: 99%

Immunomodulatory Effect of Pinus Armandi Franch Seed Oil

Guo¹,

Fang²,

Wen³

2021

Pinus armandi franch is a special local plant in China and its seed oil is a nice resource of linoleic acid (LA) and linolenic acid. This study investigated the effects of enriching the mouse diet with the ω-6 and ω-3 polyunsaturated fatty acids (PUFA), LA (18:2 ω-6) and α-linolenic acid (18:3 ω-3) different ratios (ω-6/ω-3) on total lipids in Pinus armandi franch seed oil (PAFO), and immune evaluation indexes in plasma, lymph nodes, and spleen from isolated immune cells. Kunming mice were fed a commercial chow. PAFO with a certain ratio (ω-6/ω-3) could promote the proliferation of spleen lymphocytes induced by ConA in mice and the optimal ratio was 4 or 6. PAFO with different ratios (ω-6/ω-3) could increase the spleen index and thymus index and there were significant differences between PAFO group and control group (p < 0.01). The results indicate that the ratio of ω-6 PUFA: ω-3 PUFA is 4 or 6 improve some of the indices of the mice immune status and that a moderate increase in the level of ω-6 PUFA in the mice diet does not suppress the immune system.