The role of computer-assisted analysis in the evaluation of nuclear characteristics for the diagnosis of precancerous and cancerous lesions by contact laryngoscopy.

Purpose: Contact endoscopy (CE) through the direct contact with the surface of the mucosa enables in vivo visualization of upper epithelial layers. There is a broad spectrum of laryngeal pathologies, as has been confirmed by earlier CE reports. The aim of the study was to resolve some of the limitations of CE through the application of computer-assisted image analysis.

Influence of dispersion on sensitivity of highly birefringent fibers to temperature and hydrostatic pressure.

The influence of dispersion on the sensitivity of highly birefringent fibers to temperature and hydrostatic pressure was experimentally investigated. In fibers with geometric birefringence that shows high dispersion, great differences were observed between group and phase sensitivities to temperature and hydrostatic pressure. This difference may reach 400% in the case of temperature response.

Iteration model of starch hydrolysis by amylolytic enzymes.

An elaborate computer program to simulate the process of starch hydrolysis by amylolytic enzymes was been developed. It is based on the Monte Carlo method and iteration kinetic model, which predict productive and non-productive amylase complexes with substrates. It describes both multienzymatic and multisubstrate reactions simulating the "real" concentrations of all components versus the time of the depolymerization reaction the number of substrates, intermediate products, and final products are limited only by computer memory.

Diffusion and kinetics of reaction over bidispersive reforming catalyst.

The objective of the study was to construct a mathematical model for optimizing the porous structure of the reforming catalyst. Using a layered model of the catalyst grain and the kinetic scheme adopted for the process, equations were derived to describe the mass transport in the catalyst grain under conditions of reforming. Particular consideration was given to the problem of how the parameters of the porous structure affected the efficiency of the process.

Numerical study of the influence of the shell structure of the crystalline lens on the refractive properties of the human eye.

In this paper, the numerical model of the refractive properties of the human eye is given. A special account is given of the laminated structure of the crystalline lens. The crystalline lens is presented in the form of hundreds of shells with rotational symmetry, and with the refractive index constant within each shell.

Ice/Water Interface: Zeta Potential, Point of Zero Charge, and Hydrophobicity.

The ice/water interface is a common and important part of many biological, environmental, and technological systems. In contrast to its importance, the system has not been extensively studied and is not well understood. Therefore, in this paper the properties of the H(2)O ice/water and D(2)O ice/water interfaces were investigated.

Sorbents for Trapping Organic Pollutants From Air.

A series of siliceous adsorbents with chemically bonded phases (CBPs) of different polarity were tested as sorbents for trapping air pollutants (petroleum ether) using controlled setup. Moreover, special attention was paid to the potential role of metal impurities as strong adsorption sites. Sorbents were characterized by various physico-chemical methods, such as porosimetry, inductively coupled plasma (ICP) analysis, elemental analysis, derivatography, and gas chromatography.

Decrease in 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO) EPR signal in ozone-treated erythrocyte membranes.

In ozone-treated erythrocyte membrane suspension a slow decrease occurs in the EPR signal of 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO). Because of the absence of such a phenomenon in control membranes and ozonized buffer, this effect must be caused by reaction of nitroxide radicals with products of ozone reactions with membrane components. To find out which components are responsible for the decrease in EPR signal we studied this effect in simple model systems.

UV-difference and CD spectroscopy studies on juvenile hormone binding to its carrier protein.

Juvenile hormone binding protein (JHBP) from hemolymph of Galleria mellonella is a single-chain glycoprotein of molecular mass near 25,880 containing no Trp residues. The fourth derivative of the protein absorption spectrum shows the characteristic vibrational components of the phenylalanine spectrum within the range 240-270 nm. At longer wavelengths two main bands 0-0 and 0+800 cm(-1) appear, caused by vibrational levels of electronic transition, pi-->pi*, in the tyrosine residues, with maxima at 279 nm and 286 nm, respectively.

Synthesis, Surface Properties, and Hydrolysis of Chemodegradable Anionic Surfactants: Diastereomerically Pure cis- and trans-2,5-Disubstituted-1,3-dioxanes.

In our continuing systematic studies concerning the synthesis, surface properties, and hydrolysis of chemodegradable, diastereomerically pure surface active 2,5-disubstituted 1,3-dioxane derivatives, two new groups of anionic surfactants, sodium cis- and trans-(2-n-undecyl-1,3-dioxan-5-yl)methyl sulfates and sodium cis- and trans-3-[(2-n-undecyl-1,3-dioxan-5-yl)oxy]propanesulfonates, were synthesized and investigated. Surface properties of these surfactants, i.e.

Structural and electrochemical examinations of PACVD TiO2 films in Ringer solution.

The conditions for obtaining titanium dioxide from the substrates titanium tetrachloride and oxygen and applying this to a surgical stainless steel of the type 316L by the plasma assisted chemical vapour deposition method have been determined. It was established that, during the process, titanium dioxide anatase is created, Crystallizing in a tetragonal lattice. During exposure of the 316L steel with the titanium dioxide coating, in Ringer's solution, protective properties of this covering improve.

A model of inhomogeneous expansion of the cornea and stability of its focus.

A simple derivation of an analytical condition for expanding the cornea to get the stable position of the corneal focus is given. The corneal thickness increases from the apex till the limbus and the corneal shell expands inhomogeneously as a result of changes in intraocular pressure conditions. It expands more in the centre of the cornea and less at its apex.

Electron paramagnetic resonance studies of proteins in ozone-treated erythrocyte membranes.

The sulfhydryl group specific spin labels have been used to study the membrane proteins in the bovine and human erythrocyte membranes treated with ozone. The ratio hw/hs, determined from the respective peak amplitudes of the resulting EPR spectra of 3-maleimido-1-oxyl-2,2,5,5-tetramethylpyrrolidine bound to the ozone treated membranes, was shown to be elevated following an increased ozone concentration. The ratio of the central to high-field peak amplitude h0/h-1, a measure of the rotational correlation time, determined from EPR spectra of ozonized membranes covalently labeled with 4-(iodoacetamido)-1-oxyl-2,2,5, 5-tetramethylpyrrolidine was shown to be diminished.

High precision Twyman-Green interferometer for the measurement of ophthalmic surfaces.

Purpose: We developed a method for measuring ophthalmic surfaces based on a Twyman-Green interferometer.

Methods: To demonstrate the accuracy, we measured the anterior surface of four used hard contact lenses and evaluated the interference pattern with phase shift technique. The obtained interferograms were evaluated by an image processing system.

Low pressure plasma spectroscopy - Spectrochemical analysis, technology process investigation and fundamental spectroscopic data.

Low pressure plasma, its characteristics, excitation sources and applications are shortly presented. The paper is focused on three areas of low pressure plasma spectroscopy, i.e.

Expression and purification of 6xHis-tagged DNA binding domains of functional ecdysteroid receptor from drosophila melanogaster.

Two members of the nuclear receptor superfamily, EcR and Ultraspiracle (Usp) heterodimerize to form a functional receptor for 20-hydroxyecdysone-the key ecdysteroid controlling induction and modulation of morphogenetic events through Drosophila development. In order to study aspects of receptor function and ultimately the structural basis of the ecdysteroid receptor-DNA interaction, it is necessary to produce large quantities of purified EcR and Usp DNA-binding domains. Toward this end, we have expressed the EcR DNA-binding domain and the Usp DNA-binding domain as proteins with an affinity tag consisting of six histidine residues (6xHis-EcRDBD and 6xHis-UspDBD, respectively) using the expression vector pQE-30.

Immunoaffinity purification of juvenile hormone-binding protein from Galleria mellonella hemolymph.

Previously described methods of purification of hemolymph juvenile hormone-binding protein (hJHBP) from Lepidoptera were tedious and required multiple steps. These methods resulted in low protein yield (Kramer et al., 1976; Goodman et al.

Microbial transformation of isoprenoid systems by means of fungi of Zoophthora genus--microbial transformation of compounds with alpha-campholenic system by means of fungus Zoophthora (Neopandora) sp.

Unsaturated ketones (4 and 10) and epoxides (2-3 and 8-9) were the main products of biotransformation performed by means of Zoophthora (Neopandora) phyllobii. Enantiospecificity of both reactions leading to these compounds strongly depends on the distance of reacting fragment of molecule from the chiral center at C-1'.

Urease immobilized on modified polysulphone membrane: preparation and properties.

Porous asymmetric membranes were formed by the phase inversion method from one-to-one blends of polysulphone and its aminated derivative. Amino groups were introduced into polysulphone UDEL P 1700 by chlorosulphonation followed by amination. Urease was immobilized on the modified polysulphone membranes.

Does the liquid method of electret forming influence the adhesion of blood platelets?

This work presents the results of the effect of the electric charge on the adhesion of blood platelets. All experiments were carried out on polyethylene foil. The liquid method was used to form electrets.