Computational simulation of static/cyclic cell stimulations to investigate mechanical modulation of an individual mesenchymal stem cell using confocal microscopy

Abstract

It has been found that cells react to mechanical stimuli, while the type and magnitude of these cells are different in various physiological and pathological conditions. These stimuli may affect cell behaviors via mechanotransduction mechanisms. The aim of this study is to evaluate mechanical responses of a mesenchymal stem cell (MSC) to a pressure loading using finite elements method (FEM) to clarify procedures of MSC mechanotransduction. The model is constructed based on an experimental set up in which statics and cyclic compressive loads are implemented on a model constructed from a confocal microscopy 3D image of a stem cell. Both of the applied compressive loads are considered in the physiological loading regimes. Moreover, a viscohyperelastic material model was assumed for the cell through which the finite elements simulation anticipates cell behavior based on strain and stress distributions in its components. As a result, high strain and stress values were captured from the viscohyperelastic model because of fluidic behavior of cytosol when compared with the obtained results through the hyperelastic models. It can be concluded that the generated strain produced by cyclic pressure is almost 8% higher than that caused by the static load and the von Mises stress distribution is significantly increased to about 150kPa through the cyclic loading. In total, the results does not only trace the efficacy of an individual 3D model of MSC using biomechanical experiments of cell modulation, but these results provide knowledge in interpretations from cell geometry. The current study was performed to determine a realistic aspect of cell behavior.

Enhanced depth of field of integral imaging display using bifocal microlens array fabricated by two‐step lithography

“…[6][7][8] Commonly available II system has a fixed image plane position due to the focal length being invariable, which may lead to dizziness and visual fatigue with long-time use. 9,10 Generally, a depth priority II display system can provide a reconstructed image with large depth of field (DOF), whereas the image in a resolution priority II display system with low DOF over a large spatial resolution is reconstructed. However, due to the diffraction, defocus effects, and aberration of the MLA, one of the major limitations with an II system is that it renders 3D scenes in a quite narrow DOF around its central depth plane (CDP).…”

Low-voltage driving high-resistance liquid crystal micro-lens with electrically tunable depth of field for the light field imaging system

“…Extensive study of DOF extension through imaging system based on the key MLAs has been performed 16 , 17 . Among them, the immediate approach to expand the DOF is scan the prototype by changing the focal length of the MLAs axially 18 . However, it can lead to uneven amplification and resolution problems in the LFI system.…”

29.5: Enhanced depth of field of integral imaging display using bifocal microlens array fabricated by two‐step lithography

“…[1][2][3][4][5] Thus, like the basic II technique, the quality of 3D visualization of the target object is determined by the MLAs specification, such as its numerical aperture (NA), focal length and pitch. [6][7][8] Commonly available II system have a fixed image plane position due to the focal length is invariable, which may lead to the dizziness and visual fatigue with long-time use [9][10] . Generally, a depth priority II display system that can provide reconstructed image with large DOF.…”