Cell elasticity

This is undertaken by two procedures first, empirical methods, in which variable parameters are adjusted, generally via a least squares fitting procedure to observed crystal properties. The latter must include the crystal structure (and the procedure of fitting to the structure has normally been achieved by minimizing the calculated forces acting on the atoms at their observed positions in the unit cell). Elastic constants should, where available, be included and dielectric properties are required to parameterize the shell model constants. Phonon dispersion curves provide valuable information on interatomic forces and force constant models (in which the variable parameters are first and second derivatives of the potential) are commonly fitted to lattice dynamical data. This has been less common in the fitting of parameters in potential models, which are onr present concern as they are required for subsequent use in simulations. However, empirically derived potential models should always be tested against phonon dispersion curves when the latter are available. 

Added to one-cell elastic energy, K Qe + Qs ), the two eigenvalues of this matrix represent adiabatic potential energy surfaces (APESs) shown in Fig. 4. Its shape resembles the Mexican hat. At the no-distortion point, Qe = Qe = 0, the two sheets coalesce in the electron-degenerate E term. 

Keywords QCM Cell-substrate interactions Cell adhesion Cell spreading Extracellular matrix Cellular micromechanics Cytoskeleton Cell elasticity ... 

Velegol, S. B. and Logan, B. E. 2002. Contributions of bacterial surface polymers, electrostatics, and cell elasticity to the shape of AFM force curves, Langmuir 18, 5256-5262. 

In high-temperature battery cells, elastic gaskets cannot be used for sealing, and insulation and must be replaced with ceramic materials. 

Fig. 1 Single cell elasticity measurements with microindentation technique. (A) AFM allows both live cell imaging and mechanical testing (e.g., microindentation) in near physiological conditions. The AFM tip attached to a cantilever descents slowly to a surface and causes an indentation. The depth of indentation is detected by laser light diffraction pattern. (B) Typical force-distance curves are obtained for hard and soft surfaces and usually analyzed with the classical Hertz model that relates the applied force to the indentation depth.

Kuznetsova, T.G., Starodubtseva, M.N., Yegorenkov, N.I., Chizhik, S.A., Zhdanov, R.I. Atomic force microscopy probing of cell elasticity. Micron 38, 824-833 (2007)... 

Harris AR, Charras GT (2011) Experimental validatirai of atomic force microscopy-based cell elasticity measurements. Nanotechnology 22(2011) 345102, (10 pp) lOP... 

Elastin is synthesized by fibroblasts and smooth muscle cells. Elasticity in the tissue is given by elastin (Ardelt 1964). Tissues dependent on a great degree of elasticity are, e.g., blood vessels, lung, elastic ligaments, bladder, and skin. 

Impacted force (static and inertial) Load cells, elastic elements, force gauge, balances, strain gauge, bending elements Hooke s law, transforming force to displacement by an elastic element, piezoresistive effect, capacitive effect, direct or inverse magnetostrictive and magnetoelastic effects... 

The adiabatic and isothermic bulk elasticity modules for water only slightly differ. The adiabatic modulus for water is 2.2-lO Pa. The bulk elasticity modulus for gas can be obtained from the equation of state. For ideal gas the isothermic modulus is approximately equivalent to Pa, and the adiabatic modulus is equivalent to yPA, where Pa is the pressure inside the cell, y = 1.4 the adiabatic constant. The isothermic modulus can be used in the case of infinitely slow processes. In the case of pressure oscillations at sound frequencies the adiabatic modulus should be used. Gas is much more compressible than liquids. The bulk elasticity modulus for gas is four orders of magnitude smaller than for water. Therefore, even small amounts of gas much smaller than the volume of the solution (Voas Va), can mimic small values of the effective cell elasticity modulus Eq. (6), i.e. a strong decrease of the cell resistance to pressure variations. It is extremely important to avoid the presence of any small amounts of gas in the solution because it can lead to uncontrolled changes of the effective cell elasticity modulus. 

The amplitude- and phase firequency characteristics in Fig. 8 were calculated for the conditions of the experiment shown in Fig. 9. No fitting parameters were used, except the effective cell elasticity was chosen such that the characteristic frequency corresponds to the observed... 

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