Comparison of the efficiency of titanium(IV) and iron(III) oxide nanoparticles as mediators in suppression of bacterial growth by radiation of a blue (405 nm) light-emitting diode

The effect of blue (405 nm) radiation of a light-emitting diode in combination with titanium(IV) and iron(III) oxide nanoparticles on S. aureus 209 P, S. simulans, and D. hominis bacteria is studied. It is shown that, upon irradiation of bacteria by blue (405 nm) light, Fe₂O₃ nanoparticles have a stronger (by 5–30%) antibacterial effect than TiO₂ nanoparticles.     

THz monitoring of the dehydration of biological tissues affected by hyperosmotic agents

Different ways for monitoring the dehydration of tissues affected by hyperosmotic agents have been comparatively analyzed to increase the THz transparency of biological tissues. The data obtained with an original THz laser spectrometer, a Nicolet 6700 Fourier spectrometer, and a Callegari Soft Plus system for skin diagnostics are in good agreement. The corresponding responses of biological tissues (in the form of THz transmittance, reflectance, absorption coefficient, and hydration coefficient) to the effect of biologically compatible hyperosmotic agents have been studied.     

New uranyl complex with imidazolidine-2-one [UO<Subscript>2</Subscript>(Imon)<Subscript>4</Subscript>(H<Subscript>2</Subscript>O)](ClO<Subscript>4</Subscript>)<Subscript>2</Subscript>: Structure and some properties

A complex of uranyl perchlorate with imidazolidine-2-one as the molecular ligand, [UO₂(Imon)₄(H₂O)](ClO₄)₂ (I), was synthesized and structurally characterized by X-ray diffraction analysis. The coordination number of the uranium atom is 7. The nearest environment of the uranyl ion includes four O atoms of the imidazolidine-2-one molecules and one O atom of the water molecule. The perchlorate anions are outer-sphere ligands. The crystals are monoclinic: space group P2₁/c; a = 16.294(3) Å, b = 16.135(3) Å, c = 9.987(2) Å, = 97.69 (3)°, V = 2603.0 (9) ų, (calcd) = 2.117 g/cm³, Z = 4. The IR and luminescence spectra of the complex were recorded.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 919–924.Original Russian Text Copyright © 2004 by Andreev, Antipin, Budantseva, Tuchina, Serezhkina, Fedoseev, Yusov.     

Optical clearing of skin tissue ex vivo with polyethylene glycol

Alterations of the optical and structural (weight, thickness, and square) parameters of skin caused by polyethylene glycol (PEG) with molecular weights of 300 and 400 Da were studied experimentally. The objects of the study were ex vivo skin samples of albino laboratory rats. Collimated transmittance of the skin was measured in the wavelength range 500-900 nm. As a result of exposure to the agents, an increase in the collimated transmittance and a decrease in weight, thickness, and square of skin samples were observed. Analysis of the kinetics of parameters alterations allowed us to measure the diffusion coefficient of the agents in the skin as (1.83 ± 2.22) × 10^-6 and (1.70 ± 1.47) × 10^-6 cm²/s for PEG-300 and PEG-400, respectively, and the rate of alterations of the structural parameters. The results obtained in this study can be used for the improvement of existing and development of new methods of noninvasive diagnostics and therapy of subcutaneous diseases.     

On the control of the nematic orientation on the silicon surface processed by a focused gallium ion beam

Preliminary results of studying the orientation of a 5CB nematic on the single-crystalline silicon surface processed by a 30-keV focused Ga ion beam ar e reported. It is shown that the nematic can be controllably imparted on a homeotropic or inclined orientation depending on the surface irradiation dose. By varying the scanning raster of the ion beam, one can obtain different surface patterns with a micrometer resolution and a desired orientation of the nematic.     

Use of Terahertz Spectroscopy for in vivo Studies of Lymphedema Development Dynamics

Optics and Spectroscopy - A laboratory model of lymphedema development induced by lymphatic vessel resection in rat extremities is presented. In vivo analysis of lymphedema development (monitoring...     

Photothermal Effect of Infrared (808 nm) Laser Radiation and Gold Nanoparticles in Different Modifications on S. aureus

Optics and Spectroscopy - A comparative study of the effect of infrared laser radiation (808&nbsp;nm) of different power density on Staphylococcus&nbsp;aureus&nbsp;209&nbsp;P,...