Here you will find presentations given at COMSOL Conferences around the globe. The presentations explore the innovative research and products designed by your peers using COMSOL Multiphysics. Research topics span a wide array of industries and application areas, including the electrical, mechanical, fluid, and chemical disciplines. Use the Quick Search to find presentations pertaining to your application area.

Local Electroporation of Single Adherent Cells by Micro-Structured Needle Electrodes

K. K. Sriperumbudur[1], P. J. Koester[1], M. Stubbe[1], C. Tautorat[1], J. Held[2], W. Baumann[1], and J. Gimsa[1]
[1] University of Rostock, Chair of Biophysics, Gertrudenstr. 11a, 18057 Rostock, Germany
[2] 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 ...

The Effects of the Electrical Double Layer on Giant Ionic Currents through Single Walled Carbon Nanotubes

G. Zhang[1][,][2][,][3], S.L. Bearden [1]
[1]Department of Bioengineering, Clemson University, Clemson, SC, USA
[2]Department of Electrical and Computer Engineering, Clemson University, Clemson, SC, USA
[3]Institute for Biological Interfaces of Engineering, Clemson University, Clemson, SC, USA

Electrofluidic transport through a single walled carbon nanotube (SWCNT) is enhanced by electroosmosis. Electroosmosis is made possible in these devices by the combination of a large slip length within SWCNTs and the interfacial potential at the solution/nanotube interface. A computational model of a SWCNT device was developed using COMSOL Multiphysics to investigate the complete electrical ...

Elucidating the Mechanism Governing the Cell Rotation Behavior Under DEP

G. Zhang[1], Y. Zhao[1], J. Brcka[2], J. Faguet[2], E. Lee[2]
[1]Clemson University, Clemson, SC, USA
[2]TEL U.S. Holdings, Inc., U.S. Technology Development Center, Austin, TX, USA

In our experiments with manipulating cells with DEP, we noted that some cells are constantly spining. By hypothesing that the cell spining is caused by the non-circular shape of the cell body and the off-centered location of its nucleus and that the rotation direction depends on the relative location of nucleus with respect to the electrical field, we found that the observed cell rotation was ...

Simulation of Normal and Cancerous T-cell Membrane Electroporation - new

O. Henao[1], V. Gómez[1], I. De la Pava[1], J. Sánchez[1]
[1]Grupo Fisiología Celular y Aplicada, Universidad Tecnológica de Pereira, Pereira, Risaralda, Colombia

Electroporation is an increase of the cell membrane permeability due to the formation of aqueous pores in it when the cell is under the influence of an intense electric field [1][2]. The formation of such pores in the membrane can be used to enhance the uptake of chemotherapeutic drugs into the cell in a cancer treatment known as electrochemotherapy [3]. In some cases the direct experimental ...

Modeling Bioclogging Effects in Constructed Wetlands for Wastewater Treatment - new

R. Samso[1], N. Forquet[2], P. Molle[2], J. Garcia[1]
[1]Department of Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, Barcelona, Spain
[2]IRSTEA, Freshwater Systems, Ecology and Pollution Research Unit, Villeurbanne, France

Horizontal-Flow Constructed Wetlands (HFCWs) are a particular type of biofilter, and as such they rely mostly on the activity of bacterial communities to treat wastewater. Bacterial growth in HFCWs induces dramatic changes in its hydraulic and hydrodynamic behaviour (bioclogging), which may eventually result in overland flow of wastewater. Consequently, clogging is the main cause of premature ...

Microstimulation in The Brain: Does Microdialysis Inuence the Activated Volume of Tissue?

D. Krapohl[1][3], S. Loeffler[2], A. Moser[2], and U.G.Hofmann[1]

[1]Institute for Signalprocessing, University of Luebeck, Lübeck, Germany
[2]Institute for Neurology, University of Luebeck, Lübeck, Germany
[3]Department of Information Technology and Media, Mid Sweden University, Sundsvall, Sweden

Deep Brain Stimulation (DBS) has been established as an effective treatment for Parkinson's disease and other movement disorders. The stimulation is currently administered using tetrode-macroelectrodes that target the Subthalamic Nucleus (STN). This often leads to side effects which bias the surrounding areas, e.g. the speech centre. Targeting a specific brain region can better be achieved with ...

Biosimulation of Normal Pressure Hydrocephalus Using COMSOL Multiphysics®

K. Shahim[1], J-M. Drezet[1], J-F. Molinari[2], S. Momjian[3], and R. Sinkus[4]

[1]LSMX, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
[2]LSMS, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
[3]University Hospitals of Geneva and University of Geneva, Switzerland
[4]Waves and Acoustics Laboratory, ESPCI, Paris, France

A numerical finite element model of one human brain is built in COMSOL in order to study a particular form of hydrocephalus, the so called Normal Pressure Hydrocephalus (NPH). The geometry of the ventricles and the skull is obtained by Magnetic Resonance Imaging (MRI) and imported in COMSOL Multiphysics. Form the mechanical point of view, the brain parenchyma is modeled as a porous medium fully ...

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 ...

Multiphysics Modeling of Cellular Arrays Using Periodic Minimal Surfaces – A Drug and Gene Delivery Application

J.I. Rey, A.J. Llewellyn, R.J. Connolly, J.P. Jimenez, A.M. Hoff, and R.A. Gilbert
University of South Florida, Tampa, FL, USA

Minimal surfaces are found in nature from crystalline structures to biological nano and micro structures such as biomembranes, and osseous formations in sea urchin. An application to electrically mediated drug and gene delivery is presented. Periodic level surfaces which approximate minimal surfaces are used to generate a geometric representation of tissue. A method to create such structures ...

Bone Remodeling Following Total Hip Replacement: Short Stem Versus Long Stem Implants

M.S. Yeoman[1], A. Cizinauskas[1], C. Lowry[2], G. Vincent[3], S. Collins[3], D. Simpson[3]
[1]Continuum Blue, Tredomen, Ystrad Mynach, United Kingdom
[2]Corin Group, Cirencester, United Kingdom
[3]Imoprhics, Manchester, United Kingdom

Bone resorption around hip stems, in particular periprosthetic bone loss, is a common observation post-operatively. A number of factors influence the amount of bone loss over time and the mechanical environment following total hip replacement (THR) is important. Conventional long stem prostheses have been shown to transfer loads distally, resulting in bone loss of the proximal femur. More ...