TY  - JOUR
A1  - Behbahani, Mehdi
A1  - Mai, A.
A1  - Bergmann, B.
A1  - Waluga, C.
A1  - Behr, Marek
A1  - Tran, L.
A1  - Vonderstein, K.
A1  - Mottaghy, K.
T1  - Modeling and Numerical Simulation of Blood Damage
Y1  - 2010
N1  - Posterpresentation ; Umbrella Symposium "Modelling and Simulation in Medicine, Engineering and Sciences", Forschungszentrum Jülich, January 18-20, 2010
ER  - 
TY  - GEN
A1  - Nam, J.
A1  - Arora, D.
A1  - Behbahani, Mehdi
A1  - Probst, M.
A1  - Benkowski, R.
A1  - Behr, Marek
A1  - Pasquali, M.
T1  - New computational method in hemolysis analysis for artificial heart pump
T2  - ASAIO Journal
N2  - The MicroMed DeBakey ventricular assist device is an axial flow pump designed for providing long-term support to end-stage heartfailure patients. Previously, we presented computational analysis of the blood pump flow. From the analysis, we were able to identify regions of high shear and recirculating flow that may cause blood damage, for example, deformation and fragmentation of the red blood cell (RBC). This mechanical hemolysis can be predicted using a tensor-based blood damage model that is based on the physical properties of the RBCs, for example, the relaxation time of the RBC membrane. However, an extensive and detailed analysis was complicated by the fact that the previous method predicts hemolysis along a finite number of pathlines traversed by the RBCs, possibly omitting parts of the flow domain. Furthermore, it is computationally expensive and is not easily parallelizable.
Here, we propose a new method to estimate hemolysis. The method is based on treating the shape of droplet (tensor) as a field variable, like velocity in the Navier-Stokes system. The governing equation for the RBC shape is treated by least-squares finite element method and the volume conservation of the RBC is augmented by Lagrangian multiplier. Unlike the previous method, the proposed method can visualize areas of high RBC strain that is potentially dangerous for mechanical hemolysis. Also, the amount of plasma-free hemoglobin and, consequently, normalized index of hemolysis can be computed as a byproduct. The method is tested in a simple shear flow for validation and an artery graft flow is chosen to show its potential usefulness. Finally, the method is applied to the blood damage estimation for the pump.
Y1  - 2010
U6  - https://doi.org/10.1097/01.mat.0000369377.65122.a3
N1  - 56th Annual Conference of the American Society for Artificial Internal Organs (ASAIO), May 27 - 29, 2010, Baltimore, Maryland
VL  - 56
IS  - 2
SP  - 98
PB  - Lippincott Williams & Wilkins
CY  - Philadelphia
ER  - 
TY  - JOUR
A1  - Buniatyan, Vahe Vazgen
A1  - Abouzar, Maryam H.
A1  - Martirosyan, Norayr W.
A1  - Schubert, Jürgen
A1  - Gevorgian, Spartak
A1  - Schöning, Michael Josef
A1  - Poghossian, Arshak
T1  - pH-sensitive properties of barium strontium titanate (BST) thin films prepared by pulsed laser deposition technique
JF  - Physica Status Solidi (A)
N2  - pH-sensitive properties of barium strontium titanate (BST) high-k thin films as alternative gate material for field-effect capacitive (bio-)chemical sensors based on an electrolyte-insulator-semiconductor system have been investigated. The BST films of different compositions (Ba0.31Sr0.69TiO3, Ba0.25Sr0.75TiO3 and Mg-doped Ba0.8Sr0.2Mg0.1Ti0.9O3) were deposited by pulsed laser deposition technique from targets fabricated by self-propagating high-temperature synthesis. The realised sensors have been electrochemically characterised by means of impedance-spectroscopy, capacitance–voltage and constant-capacitance method. The sensors possess a Nernstian-like pH sensitivity in the concentration range between pH 3 and 11 with a response time of 5–10 s. An equivalent circuit model for the BST-based capacitive field-effect sensor is discussed.
Y1  - 2010
U6  - https://doi.org/10.1002/pssa.200983310
SN  - 1862-6300
N1  - Special Issue: Engineering of Functional Interfaces EnFI 2009
VL  - 207
IS  - 4
SP  - 824
EP  - 830
PB  - Wiley-VCH
CY  - Berlin
ER  -