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Chitosan/gelatin and chitosan/gelatin/zeolite films prepared by solvent casting method are impregnated with a mixture of thymol and carvacrol using a green solvent, supercritical carbon dioxide at 35 °C and 30 MPa, during 18 h. Proposed method enables preparation of biocompatible and biodegradable blends with strong antioxidant and antibacterial activity, whereby amounts of loaded thymol/carvacrol (TC) mixture are in the range from 3.3% to 6%. After initial burst release, both types of films exhibit gradual release of bioactive compounds, with around 72% and 96% of impregnated TC mixture released in water and phosphate buffered saline solution (pH 7.4) during tested period of 10 days, respectively. Results of water vapor transmission rate (>76 g m−2 day−1) confirm that prepared composites are suitable for wound dressing application. Thermal analysis shows superior properties of prepared TC loaded films compared to control samples. In addition, mechanical and structural properties, as well as solubility and swelling behavior of the obtained films are investigated in detail. [ABSTRACT FROM AUTHOR]

The paper presents a statistical analysis of the impact of passengers and goods transport on environmental protection. 2017 and 2018 were analyzed from the aspect of the total number of passengers and goods, transport of passengers and goods by branches of transport, accompanying activities in traffic, border traffic, fuel consumption in the field of transport, transport of passengers and goods by months for 2018. Based on the presented statistical data, an environmental impact assessment was performed through the discharges of gloomy and nitrogen particles into the air. Concentrations and amounts of nitrogen and sulfur oxides are defined as a linear increase, ie. the impact of the transport of passengers and goods on air and the rest of the environment. The paper points to the strong impact of traffic on the environment in all areas. [ABSTRACT FROM AUTHOR]

Scattering of optical photons from the view of parallel methods related to absorption, scattering, fluorescence, reflection with inclusion of the polarization states of laser beams from experiment and theory give many possibilities for obtaining indirect data on material, processes, and dynamics. As a method with minimal perturbations, if low power beams are involved, certain type of data is provided. In fundamental dependences of various material properties, many phenomenological and basic laws are covered. Several coupled variables, primarily with the processes of scattering, pointing out further possibilities for linking the obtained theoretical or experimental results were presented. By including simulations, this associates with biological environments / variables for properties equivalent to defined tissues, cells, and characteristics. Along with selected formalisms including Stokes vectors and scattering matrices, a biological cell as an object can be monitored in time and influence of various environments could be predicted. Connecting Kerr's effect with depolarization and scattering makes the complete description of molecule possible. Angular scattering observation with experimental possibilities gives the fastest practical data. This enables interpretation of E. coli with the application of Stokes vector formalisms. A relatively small number of material constants for many simulation cases could give draft estimation, but the experiment depends on the measuring devices and samples. The necessary symmetries showing the size of the scattering centers are analyzed, with the scattering data for some liquids (known / less known). From measured data, depolarization could be calculated, and with refractive index (molar refraction) connection with Kerr effect/ birefringence for selected solutions and behavior of molecules could be monitored. From the experimental Rayleigh factors, cross section (apparent/ effective) and attenuation coefficients for pure liquids were calculated. An approach for the correct assessment of the measurement uncertainty in the process of calibration of polyethylene samples was used. [ABSTRACT FROM AUTHOR]