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- New unique optical and electric properties of intermediate filaments in Muller cellsPublication . Khmelinskii, Igor; Makarov, VladimirPresently we report new unique optical and electric properties of Muller cell (MC) intermediate filaments (IFs). We inform that these IFs extracted from porcine retina are excellent conductors of light and electric current. Such IF properties may endow vertebrate eyes with high-contrast vision. The properties of the IFs allow a simple quantum-mechanical description that justifies the quantum mechanism (QM) for the light energy transfer between the inner and the outer limiting membranes. These properties also provide direct and unequivocal proof that QM works even in isolated IFs, while the classic theory admits no capacity for light transmission by objects that are so thin. Note that the length and diameter of the IFs were 117 +/- 1.3 mu m and 10.1 +/- 0.07 nm, respectively. The QM avoids the light scattering effects, which could significantly reduce the visual contrast, by conducting light energy in the form of excitons (excited states). This scientific breakthrough may provide new insights for medical ophthalmology.
- Energy propagation along polypeptide alpha-helix: experimental data and ab initio zone structurePublication . Khmelinskii, Igor; Makarov, Vladimir, IWe report new theoretical and experimental results that may significantly change our ideas on the workings of life. We performed ab initio analysis of the band structure of periodic α-helix polypeptides (PP) in function of the chain length. Three different calculation approaches were tested: (a) PP described semiempirically as a onedimensional object, with the amino acids substituted by effective atoms; (b) density functional theory (DFT) as implemented in WIEN2k approach, and (c) CRYSTAL-17 software package. The approach (c) was used for the detailed ab initio analysis, as it provided better accuracy in less computation time. We found that the bandgap was weakly dependent on the PP composition, with the asymptotic values in the 0.43 – 0.63 eV range. We estimated the effective electron and hole masses, their mean free path and mobility for the glycine-PP. The electron mobility in the PP conductive band was about half of that in polycrystalline silicon. The PP zone structure was used to study the mechanism of energy transfer along the PP. The current-voltage (I/V) characteristics of Müller cell (MC) intermediate filaments (IFs) from porcine retina were experimentally measured. The measured I/V characteristics show that the IFs behave as semiconductors. These results were discussed in light of the presently reported PP zone structure theory. The results obtained may open new areas in biomedical research and applications.
- Electric field modulation of energy transfer along intermediate filaments isolated from porcine retinaPublication . Khmelinskii, Igor; Makarov, VladimirWe report an experimental method for simultaneous measurement of the electric properties and energy transfer by natural biological fibers. We found that energy transfer efficiency along intermediate filaments (IFs) isolated from porcine retina varied with the potential difference applied to these IFs. The maximum measured effect amounted to 25% of the transfer efficiency increase. The recorded I/U plots characteristic of the IFs demonstrate the behavior of a semiconductor with 0.62 eV band gap. These results show that the image signal might be modulated by the potential difference across the cell membrane, facilitating image contrast enhancement in the brain.
- Intermediate filaments in the retinal Muller cells as natural light energy guidesPublication . Khmelinskii, Igor; Makarov, VladimirIn the current study, we investigated transmission spectrum of the intermediate filaments (IFs) extracted from porcine retinal Muller cells (MC). The recorded transmission spectrum is quite similar to that of the entire guinea pig retina, providing direct proof that the quantum mechanism (QM) of light energy transmission through the inverted retina is in fact the main mechanism determining the high-contrast vision of the vertebrate eyes. The recorded transmission spectrum of the IFs was deconvoluted into four bands, which we assign to different types of IFs. We interpret the differences in the transmission band shape and maxima as differences in the effective electron mass, dependent on the IF structure and composition of its constituting proteins. We analyzed model systems containing IFs and dye molecules, and IFs bridging two adjacent cobalt nanofilms on a substrate. The respective results demonstrate that IFs function as waveguides transferring energy from an energy donor and to an energy acceptor, by way of the exchange mechanism. The presently reported results provide direct experimental confirmation of the earlier proposed quantum mechanism for the high-contrast vision of vertebrate eyes. The mechanism proposed in the current study may be generalized, providing a consistent alternative to Davydov's theory of vibrational solitons in enzymes.
- Optical transparency and electrical conductivity of intermediate filaments in Muller cells and single-wall carbon nanotubesPublication . Khmelinskii, Igor; Makarov, VladimirPresently we investigated the electrical conductivity and optical transparency of Muller cell intermediate filaments. For comparison, the same properties were also explored in the model system of single-wall carbon nanotubes. We report the method of separation and purification of porcine (Sus scrofa domestica) intermediate filaments, extracted from the retinal Muller cells. We also report experimental and theoretical methods of measurements and calculations of the resistivity and light transmission yield by the intermediate filaments and single wall carbon nanotubes. The measured resistivity values were (4.7 +/- 0.3) x 10(-4) and (2.8 +/- 0.2) x 10(-4) Omega.m(-1).cm(2) at 5 degrees C (278 K), for the intermediate filaments and single wall carbon nanotubes, respectively, being quite close to those of typical metals. We report a method for measuring the light energy transmission by these nanostructures. We found that they efficiently transfer excitation energy along their axis, with the light reemitted at their other end. The measured yields of transferred light energy were 0.50 +/- 0.03 and 0.26 +/- 0.02 for intermediate filaments and single wall carbon nanotubes, respectively (lambda(exc) = 546.1 nm