Ici vous trouverez les présentations issues des Conférences COMSOL à travers le monde. Réalisées par des utilisateurs de COMSOL Multiphysics, ces présentations explorent tous les domaines actuels d'innovation. Les applications couvrent pratiquement tous les secteurs industriels et impliquent des phénomènes électriques, mécaniques, fluidiques et chimiques. Utilisez la recherche rapide pour trouver les présentations les plus intéressantes dans votre domaine d'intérêt.

Hemodynamic Therapy of Middle Cerebral Artery Vasospasm Guided by a Multiphase Model of Oxygen Transport

S. Conrad[1,2], P. Chittiboina[3], and B. Guthikonda[3]

[1]Department of Bioinformatics and Computational Biology, Louisiana State University Health Sciences Center, Shreveport, LA, USA
[2]Department of Biomedical Engineering, Louisiana Tech University, Ruston, LA, USA
[3]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 ...

Drug Distribution in the Human Eye

L. Murtomäki[1], T. Kainuvaara[1]
[1]University of Helsinki, Helsinki, Finland

Drug therapy of the posterior segment of an eye is very challenging due to the difficult accessibility. Modern drugs often are large molecules, such as peptides, antibodies or oligonucleotides which are administrated, e.g. by intravitreous injections which requires clinical conditions. Computer modeling can be helpful in designing new and less invasive routes of drug administration. COMSOL is ...

Simulation of a Magnetic Induction Method for Determining Passive Electrical Property Changes of Human Trunk Due to Vital Activities

H. Mahdavi[1], J. Rosell Ferrer[1]
[1]Universitat Politècnica de Catalunya, Barcelona, Spain

The human body consists of many different types of tissues each with specific passive electrical properties. Vital activities lead to a characteristic change of these properties and geometrical changes. Magnetic induction is a non-contact method which can be used to determine these changes. The method is based on the creation of a primary magnetic field that will produce eddy currents in the ...

Can Oscillatory Convection Accelerate Signal Propagation in Simple Epithelium?

M. Nebyla[1], M. Pribyl[1]
[1]Institute of Chemical Technology, Prague, Department of Chemical Engineering, Prague, Czech Republic

We introduce a mathematical model of signal transmission in simple epithelial layers. The mathematical model consists of reaction-transport equations for extracellular ligands, cellular receptors, ligand-receptor complexes and a ligand releasing protease. We consider diffusion and nonstationary convective transport of protein ligands in the extracellular space. The study was carried out using ...

Modeling Plant Morphodynamics in Predefined COMSOL Multiphysics® Interface

S. Nikolaev[1], A. Trubuil[2]
[1]Institute of cytology and genetics SB RAS, Novosibirsk, Russia
[2]Institut National de la Recherche Agronomique, Jouy-en-Josas, France

We used a predefined COMSOL Multiphysics® interface to imitate biological growth and shape change (morphodynamics). We found a set of parameters that supply observed morphodynamics for an Arabidopsis embryo during its transition from globular to heart stage.

Simulating Light Propagation during I-PDT of Locally Advanced Head and Neck Cancer

E. Oakley [1], H. Arshad [1], G. Shafirstein [1],
[1] Roswell Park Cancer Institute, Buffalo, NY, USA

Interstitial photodynamic therapy (I-PDT) can be applied for the treatment of locally advanced head and neck squamous cell carcinoma (LA-HNSCC). The complex anatomy of LA-HNSCC requires careful planning of the light delivery and fiber insertion. We have developed an image-based approach, using finite element analysis, to suggest the number and location of treatment fibers needed for I-PDT and to ...

Simulation of Transport of Lipophilic Compounds in Complex Cell Geometry

Q.A. Chaudhry[1], M. Hanke[1], and R. Morgenstern[2]
[1]School of Computer Science and Communication, Royal Institute of Technology, Stockholm, Sweden
[2]Karolinska Institutet, Stockholm, Sweden

The mathematical modeling of the diffusion and reaction of toxic compounds in mammalian cells is tough task due to their very complex geometry. The heterogeneity of the cell, particularly the cytoplasm, and the variation of the cellular architecture, greatly affects the behavior of these toxic compounds. Homogenization techniques have been implemented for the numerical treatment of the model. ...

Finite Element Analysis of Muscular Contractions from DC Pulses in the Liver

G. Long, D. Plescia, and P. Shires
Ethicon Endo-Surgery, Cincinnati, OH, USA

Thermal ablation of malignant tumors has been conducted in patients who are not candidates for surgery for more than ten years. Recently it has been shown that low energy DC pulses can cause cell necrosis. An undesirable characteristic of DC pulses in-vivo is the stimulation of skeletal muscle. The intensity of the contraction depends in part on the duration and height of the pulse. Through the ...

Comparison of Computational Methods for the Estimation of the Dielectrophoretic Force Acting on Biological Cells and Aggregates in Silicon Lab-on-chip

S. Burgarella[1], F. Maggioni[2], and G. Naldi[2]
[1]STMicroelectronics, Agrate Brianza, Milan, Italy
[2]Department of Mathematics, University of Milan, Milan, Italy

Dielectrophoresis is a method for cell manipulation in miniaturized devices exploiting the dielectric properties of cells and/or cellular aggregates suspended in a fluid and subjected to a high-gradient electric field. The mathematical expression of the force is obtained by a multipole expansion whose terms involve increasing power of the particle\'s radius. Three methods for the expression ...

A Method for Efficient Calculation of Diffusion and Reactions of Lipophilic Compounds in Complex Cell Geometry

Kristian Dreij[1], Qasim Ali Chaudhry[2], Bengt Jernström[1], Ralf Morgenstern[1], and Michael Hanke[2]
[1]Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
[2]School of Computer Science and Communication, Royal Institute of Technology, Stockholm, Sweden

A general description of effects of toxic compounds in mammalian cells is facing several problems. Firstly, most toxic compounds are hydrophobic and partition phenomena strongly influence their behaviour. Secondly, cells display considerable heterogeneity regarding the presence, activity and distribution of enzymes participating in the metabolism of foreign compounds i.e. bioactivation ...