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The potential use of a novel multichannel optical system towards fast and non-destructive bacteria identification and its application for environmental bacteria characterisation on the strain level is presented. It is the first attempt to use the proposed optical method to study various bacteria species (Gram-negative, Gram-positive) commonly present in the environment. The novel configuration of the optical system enables multichannel examination of bacterial colonies and provides additional functionality such as registration of two-dimensional (2D) distribution of monochromatic transmission coefficient of examined colonies, what can be used as a novel optical signature for bacteria characterization. Performed statistical analysis indicates that it is possible to identify representatives of environmental soil bacteria on the species level with the 98.51% accuracy and in case of two strains of Rahnella aquatilis bacteria on the strain level with the 98.8% accuracy. The proposed method is an alternative to the currently used preliminary bacteria examination in environment safety control with the advantage of being fast, reliable, non-destructive and requiring minimal sample preparation.

Intravascular stenting of atherosclerotic coronary arteries is a life-saving, widely used procedure in interventional cardiology. Adverse clinical outcomes such as restenosis highlight the importance of meeting the excellent biocompatibility by cardiovascular implants. Many attempts have been made to improve the safety profile of implant surface. We for the first time developed the photoactive intravascular titania-based nanomaterials for the application as cardiovascular stent coating. Photoactive biomaterial deposited on the cardiovascular stent surface demonstrated promising features, making it an excellent substrate for endothelial cells growth and proliferation. The biocompatibility of these coatings has been compared with 316L stainless steel surfaces typically used in commercial coronary stents production. The results of the study proved that the innovative titania-based coatings have better biocompatibility characteristics than the 316L stainless steel and in regard of its antithrombotic potential provided protection against restenosis. Furthermore, the titania coating supported endothelial cells attachment and proliferation, and induced prolonged plasma recalcification time in comparison with stainless steel surface. Innovative photoactive titania coating can be an important factor to prevent the process of the restenosis in the place of implantation.

In the presented paper the optical system with converging spherical wave illumination for classification of bacteria species, is proposed. It allows for compression of the observation space, observation of Fresnel patterns, diffraction pattern scaling and low level of optical aberrations, which are not possessed by other optical configurations. Obtained experimental results have shown that colonies of specific bacteria species generate unique diffraction signatures. Analysis of Fresnel diffraction patterns of bacteria colonies can be fast and reliable method for classification and recognition of bacteria species. To determine the unique features of bacteria colonies diffraction patterns the image processing analysis was proposed. Classification can be performed by analyzing the spatial structure of diffraction patterns, which can be characterized by set of concentric rings. The characteristics of such rings depends on the bacteria species. In the paper, the influence of basic features and ring partitioning number on the bacteria classification, is analyzed. It is demonstrated that Fresnel patterns can be used for classification of following species: Salmonella enteritidis, Staplyococcus aureus, Proteus mirabilis and Citrobacter freundii. Image processing is performed by free ImageJ software, for which a special macro with human interaction, was written. LDA classification, CV method, ANOVA and PCA visualizations preceded by image data extraction were conducted using the free software R.

We examine the repeatability of the sol-gel production process. Methods based on statistical pattern recognition are used to evaluate microscopic images of sol-gel matrices. The applied classification is a two-steps scheme: dimensionality reduction of the data and cluster analysis. Two methods of dimensionality reduction and five methods of cluster analysis are used. We show that the repeatability varies between 82 and 93.77. The obtained results demonstrate that the molar ratio Rof the number of solvent moles to the number of substrate moles influences the stability of sol-gel materials, thus enabling us to reach a higher repeatability in the production process in the case of sol-gel produced with the addition of detergent. © 2003 Society of Photo-Optical Instrumentation Engineers.

A new representation for the D log E curve for photographic emulsions, based on the Fermi formula, is presented. This representation uses easily measured photometric parameters and is conveniently adapted for different kinds of absorption holographic recording materials. The corresponding transmittance-versus-exposure curve is used to calculate the influence of film nonlinearity on Fourier-transform hologram-recording parameters.

A new representation for the D log E curve for photographic emulsions, based on the Fermi formula, is presented. This representation uses easily measured photometric parameters and is conveniently adapted for different kinds of absorption holographic recording materials. The corresponding transmittance-versus-exposure curve is used to calculate the influence of film nonlinearity on Fourier-transform hologram-recording parameters.

Bacteria, viruses and parasites elimination from human environment is one of the most important problem, extensively studied by many groups. The growing resistance to commonly used disinfection and/or sterilization methods and antibiotics, is one of the major problem in the health care sector. Nanomaterials with tailored antimicrobial features may find applications in this field. One of the promising application of nanomaterials is the possibility to enhance the antimicrobial photodynamic therapy (APDT), which combines a nontoxic photoactive dye - photosensitizer and nanomaterials properties. This paper focused on the examination of optical and antibacterial properties of silica- and titania-based nanopowders doped with silver and photosensitizer - Photolon. Various concentration of Photolon and nanomaterials have been prepared in order to examine the fluorescence enhancement and resulting better antibacterial activity. It was proved that the fluorescence intensity of Photolon increased, depending on silver concentration. Antibacterial study showed that silver doped silica and titania nanoparticles revealed antibacterial activity, but in the presence of Photolon, the antibacterial activity of materials is more effective.