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This research aims to determine if the observed improvements using polyethylene (PE) waste in asphalt binder translate into better performance at the asphalt mixture scale in the laboratory environment while overcoming the stability and homogeneity issues experienced at the binder level. This is accomplished through a round-robin multinational experimental program covering four continents, with the active participation of eleven laboratories within the RILEM TC 279-WMR. PE modified AC16 mixtures were prepared employing the dry process using local materials with the PE waste provided by one source. Various mechanical tests were performed to investigate the compactability, strength, moisture sensitivity, stiffness and permanent deformation. Compared to the control mixtures, the following observations were made for PE modified mixtures: easier to compact, lower time dependence of stiffness, higher elastic behavior, lower creep rate, and higher creep modulus. Furthermore, cyclic compression test results showed that the resistance to permanent deformation is improved when using PE in asphalt mixtures, whereas the wheel tracking tests showed relatively similar or better results when 1.5% PE was added to the control mixture. The wheel tracking test results in water showed an increase in deformation with increasing PE content. The interlaboratory investigation showed that the use of PE as a performance-enhancing additive in asphalt pavements is a viable, environmentally friendly option for recycling waste plastic and could potentially reduce the use of polymer additives in asphalt.

Suitability of bentonite clay modified with sodium carboxymethyl cellulose (Na-CMC) for the removal of arsenic(III) ions from aqueous solution was tested in batch adsorption studies and complemented by theoretical modeling with Langmuir, Freundlich and Temkin isotherm models. The effects of various factors, such as the initial adsorbate concentrations, pH, and temperature of the solutions were investigated in series of experiments. FTIR analysis was used to detect functional groups typical for cellulose and bentonite. Scanning electron microscope was used to analyze the surface morphology of the composites. It was established that the removal process was fast in the beginning and adsorption equilibrium was attained in around 20 minutes with good fittings to both Langmuir and Freundlich model. Maximum adsorption capacity (Q max ) obtained from experiments was 9.4 mg/g. No influence of solution pH and temperature on the sorption was noticed. The series of conducted experiments showed that synthesized composites are suitable for the removal of arsenic from wastewaters by adsorption as efficient and low-cost technique. © 2019, ALÖKI Kft., Budapest, Hungary.

Gut microbiota and gut-associated lymphoid tissue have been increasingly appreciated as important players in pathogenesis of various autoimmune diseases, including multiple sclerosis. Experimental autoimmune encephalomyelitis (EAE) is an animal model of multiple sclerosis that can be induced with an injection of spinal cord homogenate emulsified in complete Freund's adjuvant in Dark Agouti (DA) rats, but not in Albino Oxford (AO) rats. In this study, mesenteric lymph nodes (MLN), Peyer's patches (PP) and gut microbiota were analysed in these two rat strains. There was higher proportion of CD4(+) T cells and regulatory T cells in non-immunised DA rats in comparison to AO rats. Also, DA rat MLN and PP cells were higher producers of pro-inflammatory cytokines interferon-gamma and interleukin-17. Finally, microbial analyses showed that uncultivated species of Turicibacter and Atopostipes genus were exclusively present in AO rats, in faeces and intestinal tissue, respectively. Thus, it is clear that in comparison of an EAE-susceptible with an EAE-resistant strain of rats, various discrepancies at the level of gut associated lymphoid tissue, as well as at the level of gut microbiota can be observed. Future studies should determine if the differences have functional significance for EAE pathogenesis.

Among the modified BaTiO3 La doped BaTiO3-ceramics are intensively studied because of their attractive ferroelectric properties that can be tailored to meet the strong demands for various electroceramic components. In this investigation La/Mn codoped BaTiO3 with different La2O3 content, ranging from 0.1 to 5.0 at% La, was investigated regarding their microstructural characteristics. Microstructural and compositional studies were performed by scanning electron microscopy (JEOL-JSM 5300) equipped with EDS (QX 2000S) system. Depending on the amounts of dopants and sintering temperature a huge range of microstructure features can be observed in doped ceramics, together with the appearances of secondary phases that are formed above eutectic temperature. The morphology of ceramics grains pointed out the validity of developing new structure analytical methods, based on different grains' shape geometries. The new correlation between microstructure of doped BaTiO3-ceramics, based on fractal geometry and contact surface probability, has been developed. Using the fractals and statistics of the grains contact surface, a reconstruction of microstructure configurations, as grains shapes or intergranular contacts, has been successfully done. The directions of possible materials properties prognosis are determined according to the correlations synthesis-structure-property.

Bioresorbable barrier membranes have been widely used in dentistry and maxillofacial surgery. When the membranes are placed over bony defects and are closely adapted by the surrounding bone face, an environment that prevents invasion of competing non-osteogenetic cells from the overlying soft tissues can be created. The aim of the present study was to establish whether the production procedure of different polymeric and composite membranes affects their physicochemical properties. The physicochemical properties were examined by differential scanning calorimetry (DSC), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), inverse gas chromatography (lGC) and tensile strength test (TST). The surface microstructure, dependent on the processing parameters, was perforated with smaller or larger pores. The dispersive component of the free surface energy decreased by adding bicalcium phosphate (BCP) to the polymer and, consequently, non-polar interactions with the surroundings became preferential.

Si3N4-TiN composites, with varying TiN content from 0-50 wt% and beta-Si3N4 seeds up to 5 wt%, were examined in respect of their electrical resistivity and fracture toughness. The composites are produced by liquid phase sintering using 3%Al2O3+7%Y2O3 as additive. beta-seed particles with different particle shape and aspect ratio were used in this investigation. The electrical conductivity of composites exhibits a percolative behaviour, which is characterised by an abrupt decrease in resistivity in composites with 36 wt%TiN. In composites with beta-Si3N4, for the same percolation concentration of TiN, the electrical resistivity is higher than in composites without seed particles. The fracture toughness shows a considerable improvement in Si3N4-36%TiN with 3 and 5 wt% seeds. High fracture toughness of 6.10 MPa m(1/2) could be achieved due to the controlled bimodal microstructure consisting of elongated beta-Si3N4 incorporated into a composite matrix.

Bioresorbable barrier membranes have been widely used in dentistry and maxillofacial surgery. When the membranes are placed over bony defects and are closely adapted by the surrounding bone face, an environment that prevents invasion of competing non-osteogenetic cells from the overlying soft tissues can be created. The aim of the present study was to establish whether the production procedure of different polymeric and composite membranes affects their physicochemical properties. The physicochemical properties were examined by differential scanning calorimetry (DSC), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), inverse gas chromatography (lGC) and tensile strength test (TST). The surface microstructure, dependent on the processing parameters, was perforated with smaller or larger pores. The dispersive component of the free surface energy decreased by adding bicalcium phosphate (BCP) to the polymer and, consequently, non-polar interactions with the surroundings became preferential.