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A two-dimensional modeling of binary coalescence time using the two-color lattice-Boltzmann method
No full textabstractEN: A lattice-Boltzmann method (LBM) was used for simulation of the 2D binary coalescence of droplets. The main subject of our interests is the influence of the droplet size and the interfacial tension on binary coalescence time (BCT). The BCT of two free particles as well as the case when one of the particles is deposited on the surface is considered. The results of calculations are in good agreement with experimental data presented in other papers.score: 35collation: 355-36
Designing of High-Speed Machine Shafts of Carbon Composites with Highly Nonlinear Characteristics
No full textscore: 8collation: 76-8
New Method for Testing the Dynamic Performance of CMM Scanning Probes
No full textabstractEN: In this paper, a new method that applies a piezoelectric translator to test the dynamic accuracy of scanning probes for coordinate measuring machines (CMMs) is proposed. The principle of the method is presented, and this method is used for the evaluation of measurement uncertainty. The validity of the method is experimentally confirmed on a bridge Zeiss PRISMO CMM equipped with a VAST XT scanning probe.score: 25collation: 2767-277
Fabrication of biocompatible hydrogel coatings for implantable medical devices using Fenton-type reaction
No full textabstractEN: In this paper the authors present a simple method of coating polyurethane (PU) surface with poly(vinyl pirrolidone) (PVP) hydrogel. The hydrogel-coated materials were designed for use in biomedical applications, especially in blood-contacting devices. The coating is formed due to free radical macromolecular grafting–crosslinking. Polymer surface was first immersed in an organic solution containing radical source: cumene hydroperoxide (CHP) with an addition of a branching and anchoring agent: ethylene glycol dimethylacrylate (EGDMA). In the second step, the substrate was immersed in a water solution containing given concentration of PVP and Fe2+. The novelty of the process consists in the fact that free radicals are formed mostly at the polymer/solution interface, what assures high grafting efficiency together with the formation of covalent bonds between polymer substrate and modifying layer. The process was optimized for reagents concentrations. The coating properties: thickness and the swelling ratio were strongly influenced by CHP, Fe2+, PVP and EGMDA concentrations. The chemical composition of the surface analyzed with FTIR-ATR spectroscopy confirmed the presence of PVP coating. In vitro biocompatibility tests with L929 fibroblasts confirmed non-cytotoxicity of the coatings. Hydrogel coating significantly improved polyurethane hemocompatibility. Studies with human whole blood revealed that both, the platelet consumption and the level of platelet activation were as low as for negative control.score: 25collation: 1601-160
Encapsulation of proteins by Electro Hydro Dynamic Atomization
No full textabstractEN: Summary: Aerosol reactor for Electro Hydro Dynamic Atomization has been used to encapsulate water soluble proteins in poly(ε-caprolactone). As a raw material w/o emulsion of BSA water solution emulsified in the organic solution of polymer was applied. Stability of the spraying process itself for particles production was investigated. Also raw material emulsion stability has been examined and emulsion stabiliser has been found. Protein release rate from produced particles was determined.score: 0collation: 98-10
Influence of the coating process parameters on the quality of PUR/PVP hydrogel coatings for PVC medical devices
No full textabstractEN: To decrease friction factor and enhance the biocompatibility of medical devices manufactured from poly(vinyl chloride), PVC, the surface modification with wear resistant polyurethane/polyvinylpyrrolidone (PUR/PVP) hydrogel coating can be applied. In the present work substrates were dip-coated with PVP and PUR solutions and thermally cured. The variable process parameters were: solvent system; concentration of polymers (1, 2 or 3\% w/v); coating baths temperature (22, 38 and 55°C); drying temperature (32, 50 and 67°C); length of break between process steps (5, 30 and 90 s); and solutions storage time (up to 72 hrs). The quality of coatings was determined by friction coefficients against porcine aorta, weights of the deposited layer and the swelling capacity. The solvent system and polymers concentration were crucial factors. The increased temperature of coating solutions caused increased deposition but decreased durability. The most lubricious samples were dried in 50°C. Coatings from the solutions prepared 24h prior to use had better properties than those from fresh solutions.score: 15collation: 38-4
Porous crosslinked PDMS-microchannels coatings
No full textabstractEN: Microchannels prepared in poly(dimethylsiloxane) (PDMS) structures were coated with a liquid emulsion which was then crosslinked creating a porous layer on walls of the channels. The emulsion contained a PDMS prepolymer mixed with a porogen. In this initial work water was used as a porogen. Having pumped the emulsion through the microchannel, the whole structure was cured at 120 °C in order to crosslink the emulsion and allow to evaporate a porogen. As a result a porous layer on the microchannel's walls was obtained with a so-called open porosity. The evaluation of the porosity was done with the help of numerical analysis. Pores with an equivalent diameter on the order of 4–6 μm were fabricated. Further, fabrication of gas sensor containing a porous layer with a pH indicator is described.score: 40collation: 68-7
Adding numbers with DNA
No full textabstractEN: A novel algorithm based on DNA computing for adding binary integer numbers is presented. It requires the unique representation of bits placed in test tubes treated as registers. Amplification step used for the carry operation allows one, in theory, to add numbers with the same quantity of elementary operations, regardless of the number of bits used for representation. New notation proposed in the paper allows for efficient and abstract description of the technical operations on DNAscore:
Efficient reagent immobilization procedure for ion-sensitive optomembranes
No full textabstractEN: This paper presents an efficient and simple reagent immobilization procedure for ion-sensitive membranes of fiber-optic chemical sensors. The applied procedure combines two well-known types of sensing optrode layers: the surface membrane and the bulk type using a polymer track membrane (PTM). The microporous polymer foil significantly increases the active surface of the membrane for reagent immobilization and allows a larger amount of an indicator dye to be incorporated, which leads to large changes in the measured signal. Additionally, the high porosity of a PTM reduces the barrier of mass transport, which decreases the response time of prepared optomembranes. The preparation and performance of optrodes for redox titration and pH fiber-optic sensors based on cellulose acetate PTMs are described.score: 40collation: 207--21
Design and synthesis of CK2 inhibitors
No full textabstractEN: A series of new polybrominated benzimidazoles and benzotriazoles has been synthesized and their influence on the activity of protein kinase CK2 was evaluated. It was revealed that the most active inhibitors are those with methyl or ethyl substituent at benzene ring, namely 5,6,7-tribromo-4-methyl-1H-benzotriazole (38, IC50 0.51 μM) and 5,6,7-tribromo-4-ethyl-1H-benzotriazole (40, IC50 0.16 μM). The derivatives with large aromatic or heterocyclic substituents connected to benzimidazole or benzotriazole scaffold appeared to be less potent inhibitors.score: 0collation: 91-9