A solution to Bloch NMR flow equations for the analysis of hemodynamic functions of blood flow system using m-Boubaker polynomials

2009 ◽  
Vol 9 (1) ◽  
pp. 278-283 ◽  
Author(s):  
O. Bamidele Awojoyogbe ◽  
Karem Boubaker
Keyword(s):  
Blood Flow ◽  
Flow System ◽  
Flow Equations ◽  
Boubaker Polynomials ◽  
Bloch Nmr Flow Equations

A model of a human heart via graph nano topological spaces

2019 ◽  
Vol 12 (01) ◽  
pp. 1950006 ◽  
Author(s):  
Ashraf S. Nawar ◽  
Abd El Fattah A. El Atik
Keyword(s):  
Blood Flow ◽  
Blood Circulation ◽  
Human Heart ◽  
Flow System ◽  
Real Life ◽  
Topological Spaces ◽  
Neighborhood System

In this paper, new forms of nano topological spaces through a neighborhood system of vertices for a digraph will be presented and studied. We apply the connection between digraph theory and nano topological spaces in the human heart as an example in real life. We have a blood flow system in the human heart with respect to oxygenated and deoxygenated blood circulation. Our study will be definitely helpful to develop a tool in solving the blood flow system in the human heart. Finally, we have succeeded in improving Proposition 1.6 in [7] and Proposition 4.4.1 in [11].

scholarly journals Investigation of blood flow through an artery in the presence of overlapping stenosis

2017 ◽  
Vol 14 (1) ◽  
pp. 39-46 ◽  
Author(s):  
K. Maruthi Prasad ◽  
S. Thulluri ◽  
M. V. Phanikumari
Keyword(s):  
Blood Flow ◽  
Shear Stress ◽  
Pressure Drop ◽  
Wall Shear Stress ◽  
Couple Stress ◽  
Flow Characteristics ◽  
Couple Stress Fluid ◽  
Flow Equations ◽  
Wall Shear ◽  
Fluid Parameters

The effects of an overlapping stenosis on blood flow characteristics in an artery have been studied. Blood has been represented by a couple stress fluid. The flow equations have been linearised and the expressions for pressure drop, resistance to the flow and wall shear stress have been derived. The results are shown graphically. It is observed that the resistance to the flow, pressure drop and wall shear stress increases with height and length of the stenosis. And it is noticed that the resistance to the flow and pressure drop decreases with couple stress fluid parameters. But wall shear stress increases with couple stress fluid parameters.

Leucocyte-Reduced Buffy Coat Platelet Concentrates (BCPC) Treated with INTERCEPT™ Stored up to 7 Days: Hemostatic Function in a Whole Blood Flow System.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 956-956
Author(s):  
Miguel Lozano ◽  
Ana Galan ◽  
Roberto Mazzara ◽  
Laurence Corash ◽  
Gines Escolar
Keyword(s):  
Blood Flow ◽  
Platelet Count ◽  
Whole Blood ◽  
Flow System ◽  
Ex Vivo ◽  
Buffy Coat ◽  
Platelet Concentrates ◽  
Platelet Storage ◽  
Pre Treatment ◽  
Additive Solution

Abstract Background: The risk of bacterial growth has limited the shelf life of platelet concentrates (PC) to 5 days. Modern platelet storage containers facilitate storage for up to 7 days, if bacterial contamination is prevented. INTERCEPT (Baxter, La Chatre, France; Cerus, Concord, CA) photochemical treatment (PCT) for pathogen reduction based on amotosalen (150μM) and UVA illumination (3 J/cm2) inactivates high titers of bacteria in PC (Transfusion2004; 44: 1496–1504). Adhesion and aggregation of platelets to injured vascular surfaces are critical aspects of platelet hemostatic function. In this study, the adhesion and aggregation of leucocyte-reduced buffy coat derived PC (BCPC), treated with INTERCEPT and stored up to 7 days, were measured on injured vascular surfaces using an ex-vivo blood flow system. Methods: BCPC were prepared from 450 mL-whole blood donations with the top and bottom method (Optipress II, Baxter). Five BCPC, of the same ABO group, were pooled with additive solution (Intersol™) the day following collection, after viral screening testing was completed. Following centrifugation and leukocyte depletion, two BCPC pools of the same ABO group were mixed and divided. One pooled BCPC was treated with INTERCEPT (I-BCPC) and the other was prepared by conventional methods (C-BCPC); and both were stored in 1.3 liter PL2410 plastic containers (Baxter R4R7012) at 22 ± 2°C with continuous agitation for 7 days. Samples for hemostatic function testing were taken immediately after preparation before splitting for treatment and after 5 and 7 days of storage. Platelet counts were performed in K3EDTA in a Coulter MD II counter (Coulter, Miami, FL). Samples of I-BCPC and C-BCPC were added to citrate anticoagulated blood, previously depleted of platelets and leukocytes by filtration, and adjusted to a final platelet count of 150x109/L. Enzymatically denuded vascular segments were exposed to circulating whole blood, reconstituted with I-BCPC and C-BCPC, in Baumgartner chambers at a shear rate of 800 s−1 for 10 minutes. The proportion (%) of the vascular surface area covered by platelets after perfusion was measured for each type of BCPC (N = 9) at each storage time point. Platelets and groups of platelets were classified as adhesive when platelet masses were less than 5 μm in height and as thrombi when height exceeded 5 μm. Data were analyzed with the SPSS 12.0.1 statistical package with significance at p < 0.05, and expressed at the mean ± SEM Results(Table). Conclusion: The platelet count of I- BCPC decreased by 12.3% including PCT processing losses and 7 days of storage. However, I- BCPC platelet adhesive and aggregatory capacities under flow conditions were similar to C- BCPC, and were well conserved for up to 7 days of storage. Hemostatic Function of Stored I-BCPC and C-BCPC Parameter I-BCPC C-BCPC p Day 1(Pre Treatment) Platelet Count (109/L) 945±40 945±40 Platelet Coverage (%) 26.0±3.7 26.0±4.2 Adhesion(%) 24.0±3.7 24.0±3.7 Thrombus(%) 1.9±0.6 1.9±0.6 Day 5 Storage Platelet Count (109/L 844±41 902±44 0.004 Platelet Coverage (%) 20.9±2.2 20.6±1.6 0.9 Adhesion(%) 19.9±2.1 19.3±1.4 0.8 Thrombus(%) 0.9±0.3 1.2±0.4 0.5 Day 7 Storage Platelet Count (109/L) 829±32 923±48 0.008 Platelet Coverage (%) 27.1±2.9 21.2±2.8 0.06 Adhesion(%) 26.0±2.7 20.4±2.7 0.06 Thrombus(%) 1.2±0.3 0.7±0.2 0.16

UNSTEADY BLOOD FLOW IN AN ARTERY WITH AN OVERLAPPING STENOSIS

2012 ◽  
Vol 04 (02) ◽  
pp. 1250016 ◽  
Author(s):  
DANIEL N. RIAHI ◽  
RANADHIR ROY
Keyword(s):  
Blood Flow ◽  
Shear Stress ◽  
Flow System ◽  
Red Cells ◽  
Fluid Viscosity ◽  
Critical Height ◽  
Viscosity Modeling ◽  
Temporal And Spatial ◽  
Unsteady Blood Flow ◽  
Velocity Pressure

We consider the problem of unsteady blood flow in an artery and in the presence of an overlapping symmetric stenosis. The blood flow in the arterial tube is assumed to be a suspension of red cells in plasma. The present formulation makes use of the variable fluid viscosity modeling that takes into account the amount of the red cells in the blood fluid flow system. Using both analytical and computational methods, we determine the expression for various quantities such as the leading order flow velocity, pressure gradient, impedance and shear stress at the throats and at the critical height, and we calculate dependence of these quantities on the temporal and spatial variables as well as on the frequency of the flow oscillation and the main parameters of the flow system. We find, in particular, that the higher value of the frequency can lead to higher values of the magnitude for the quantities such as the axial velocity, the impedance and the wall shear stress in the stenosis zone particularly if the stenosis is less mild.

An Artificial Cadaveric Leg Blood Flow System for Endoscopic Vein Harvesting Simulation

2017 ◽  
Vol 12 (5) ◽  
pp. e16-e18 ◽  
Author(s):  
Constantine L. Karras ◽  
Emily A. DeDonato ◽  
Kaitlin K. DiBartola ◽  
Jin-Cheng Zhao
Keyword(s):  
Blood Flow ◽  
Saphenous Vein ◽  
Flow System ◽  
Training Model ◽  
Surrounding Tissue ◽  
Medial Malleolus ◽  
Bipolar Coagulation ◽  
Artificial Blood ◽  
Endoscopic Vein Harvesting ◽  
Vein Harvesting

Despite being the most common training model for endoscopic vein harvesting, cadaveric legs are limited by their absence of blood flow, resulting in a faded vascular appearance. Because the saphenous vein and the surrounding tissue seem less distinguishable, dissection of the saphenous vein and bipolar coagulation of its branches becomes increasingly inefficient and difficult. An inexpensive artificial blood flow system was developed to overcome this limitation. A cadaveric leg was thawed to a soft and yielding degree, and the saphenous vein was dissected medial and proximal to the medial malleolus. An artificial blood solution was prepared by dissolving 4% protein powder, red dye, and a contrast agent—for x-ray visualization—in saline. The solution was perfused through the saphenous vein and artery. The open ends of the vessels were temporarily clamped after the perfusion had been completed. Blood flow within the vessels was confirmed via angiography and endoscopic visualization of the leg's vessels. A bleeding effect was observed when the saphenous vein was perforated or when a vascular branch was transected. Conversely, a tight seal indicated successful bipolar coagulation of a branch, providing an objective, quantifiable assessment parameter. The artificial blood flow system helps overcome the limitations of the cadaveric leg, creating a more realistic and inexpensive model for endoscopic vein harvesting simulation training.

Device for UV irradiation of blood with a disposable blood flow system

1999 ◽  
Vol 66 (2) ◽  
pp. 315-318
Author(s):  
G. I. Levashenko ◽  
N. V. Mazaev
Keyword(s):  
Blood Flow ◽  
Uv Irradiation ◽  
Flow System
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