R. Penjweini, M. M. Kim, T. C. Zhu
Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
Introduction: Singlet oxygen (¹O₂) has a critical role in the cell-killing mechanism of photodynamic therapy (PDT). Therefore, in this study, the distance-dependent reacted ¹O₂ is numerically calculated using finite-element method (FEM). Herein, we use a model [Ref. 1] that has been previously developed to incorporate the diffusion equation for the light transport in tissue and the ...
Temperature Excursions at the Pulp-Dentin Junction during the Curing of Light-Activated Dental Restorations
M. Jakubinek[1,2], C. Neill, C. Felix, R. Price[2,3], M. White[1,2]
Departments of Chemistry and Physics, Dalhousie University, Halifax, NS, Canada
Institute for Research in Materials, Dalhousie University, Halifax, NS, Canada
Department of Dental Clinical Sciences, Dalhousie University, Halifax, NS, Canada
Heat produced during the curing of light-activated dental restorations could damage the dental pulp. Given the prevalence of composite restorations and the importance of avoiding injury to the pulp, efforts should be made to minimize the temperature increase that occurs at the pulp-dentin junction during light-curing. In this investigation we develop and evaluate a COMSOL Multiphysics FEM tooth ...
Search for a Suitable Numerical Model for Electrical Stimulation: from the Electric Double Layer to Electrokinetics, Confrontation with Impedance Measurements
P. Pham, R. Scapolan, C. Rubeck, and F. Dupont
CEA-LETI-MINATEC, Grenoble, France
Electrical Stimulation is widely used today for Deep Brain Stimulation treatments and retinal prostheses. The Electrical Double Layer formed at the interface between the electrode surface and the extracellular medium is considered thru the linear Helmholtz model and the nonlinear more realistic modified Poisson Boltzmann model. These different models, solved using COMSOL Multiphysics, are ...
P. Lezuo, M. Stoddart, and M. Alini
AO Research Institute, Davos, Grison, Switzerland
We aim to develop an in vitro culture system to mimic the human bone marrow stem cell niche in an artificial perfusion bioreactor environment to culture human adult stem cells. State of the art human bone marrow stem cell research shows that even smallest changes in the physical, thermo dynamical or biochemical environment induce a differentiation of human bone marrow stem cells into other cell ...
Evaluation of Performance of Enzymatic Biofuel Cells with Microelectrode Arrays Inside a Blood Artery via Finite Element Approach
C. Wang, Y. Song
Florida International University, Miami, FL, USA
Enzymatic biofuel cells (EBFCs) are considered as a promising candidate for powering miniature implantable devices. In order to predict the performance in the human blood artery, we simulated a 3D EBFC chip with highly dense micro-electrode arrays. In this simulation using COMSOL Multiphysics®, we applied the 1) Michaelis Menten equation; 2) Nernst potential equation; 3) Navier Strokes velocity, ...
K. K. Sriperumbudur, P. J. Koester, M. Stubbe, C. Tautorat, J. Held, W. Baumann, and J. Gimsa
 University of Rostock, Chair of Biophysics, Gertrudenstr. 11a, 18057 Rostock, Germany
 Microsystem Material Laboratory, Department of Microsystems Engineering (IMTEK), University of Freiburg, Germany
In spite of its low throughput, Patch-Clamp is the established method for intracellular measurements of the transmembrane potential. To address this problem, we have developed new biosensor-chips with micro-structured needle electrodes (MNEs). MNE-penetration of single cells growing on the MNE-tips leads to a situation comparable to the whole-cell mode in classical Patch Clamp. MNE-penetration ...
M. Blaziková, J. Malínský, D. Stanek, and P. Herman
Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
Institute of Experimental Medicine, Prague, Czech Republic
Institute of Molecular Genetics, Prague, Czech Republic
Small nuclear ribonucleoprotein particles (snRNPs) are essential supramolecular complexes involved in pre-mRNA splicing, the process of post-transcriptional RNA modifications. The particles undergo complex assembly steps inside the cell nucleus in a highly dynamic compartment called the Cajal body. We have previously shown that the free diffusion model does not fully describe the snRNP motion ...
I.M. Abdel-Motaleb, J. Lavrencik 
Department of Electrical Engineering, Northern Illinois University, DeKalb, IL, USA
There is urgent need to monitor dental and oral diseases, such as tooth decay, gum diseases, and teeth grinding. Such monitoring can be achieved by embedding sensors in the mouth. This technique faces some difficulties. The first is how the power needed for the operation of the sensors and the associated electronic chips can be generated. This power can be generated using the pressure exerted by ...
A. Candeo and F. Dughiero
Department Electrical Engineering, University of Padova, Padova, Italy
Radiofrequency Ablation (RFA) represents a valid alternative for treating liver metastases in medically complicated patients. Conventional devices currently operate at 500 kHz, due to good conducting properties of tissues. However, the use of lower frequencies (i.e. 20 kHz) has been recently reported to enhance the treatment effectiveness, due to a more pronounced difference in electrical ...
Hemodynamic Therapy of Middle Cerebral Artery Vasospasm Guided by a Multiphase Model of Oxygen Transport
S. Conrad[1,2], P. Chittiboina, and B. Guthikonda
Department of Bioinformatics and Computational Biology, Louisiana State University Health Sciences Center, Shreveport, LA, USA
Department of Biomedical Engineering, Louisiana Tech University, Ruston, LA, USA
Department of Neurosurgery, Louisiana State University Health Sciences Center, Shreveport, LA, USA
Cerebral vasospasm is a complication of subarachnoid hemorrhage and other neurosurgical emergencies that reduce blood flow to the brain. Part of the approach to management of vasospasm is to improve flow through the stenotic areas by reducing by decreasing blood viscosity and enhancing flow through the stenosis. To examine the interaction of these factors, we applied computational fluid dynamics ...