Frequency domain causality analysis of intra- and inter-regional return and volatility spillovers of South-East European (SEE) stock markets

In this study the return spillovers and volatility spillovers between South-East European (SEE) stock markets are investigated as well as vis-a-vis regional and global stock markets (e.g. Europe, Japan, China and the US). By using Frequency Domain Causality approach, the evidence is found of significant spillover effects between markets. The results of study indicate both short-and long-run intra- and inter-regional return and volatility spillovers detected between South-East European (SEE) stock markets and the emerging and the mature markets around the globe, implying limited diversification benefits for international investor portfolios allocated to these markets. Thus, these results should be taken into account by portfolio managers, investors and policy makers before making any investment decision into region’s stock markets. The policy makers and regulators of these markets should consider the nature and frequency of regional and global integration of their stock markets

The Influence of Breastfeeding and the Infant’s Social Environment on Neuroplasticity and Brain Development: The First 1000 Days

There is substantial evidence that breastfeeding and an enriched environment provide significant contributions to the infant’s brain development. In the past 2 decades, there have been overwhelming data on the benefits of breastfeeding for 1 year and longer and its association with higher intelligence in later life. There is clear and convincing evidence from a number of disciplines, neuroscience, genetics, animal experiments and magnetic imaging techniques that indicate breastfeeding results in optimal brain development and higher IQ in later life. Magnetic imaging studies of infants, children and adolescents have provided significant evidence that the higher IQ in later life in breastfed infants is associated with larger brain size and higher degree of myelination of the white matter. Furthermore, observational studies of infants have provided clear evidence that breastfeeding and mother-baby sensory interaction result in significant cognitive and behavioral development of breastfed as compared to formula fed infants. Large-scale longitudinal studies of infants’ development have shown clear and convincing evidence of higher intelligence in children who were breastfed during infancy, and that the higher IQ persists through adulthood. In this communication, we provide evidence that breastfeeding and an enriched environment result in accelerated developmental potentials in the first 1000 days last a life time. The first 1000 days last the rest of our lives

Effect of Component Geometry and Build Orientation on the Microstructure and Mechanical Properties of Nickel Superalloys Manufactured with Laser Powder Bed Fusion

Metal laser powder bed fusion (PBF-LB/M) enables high geometric design freedom. However, the resulting PBF-LB/M microstructure depends on several factors, including process parameters, part geometry, build orientation and post-processing (e.g. heat treatment) etc. The correlation between the PBF-LB/M microstructure and the influencing factors is not yet sufficiently researched or understood. Thus, there is currently a lack of transferable databases and reproducible test procedures, especially for high temperature materials. Since the geometry of components used in applications generally differs from standard witness samples, it must be investigated whether directly printed PBF-LB/M witness samples exhibit comparable material properties to samples extracted from components. Within the scope of this thesis, a generic component was designed with application-relevant geometric features, such as overhangs, changes in cross-section, etc. Witness samples were integrated within the generic component, which combined, form the Sample Extraction Component (SEC). The (witness) samples are manufactured in three build orientations: 0° (perpendicular to the build direction), 45° and 90° (parallel to the build direction). The samples extracted from the SEC are microstructurally and mechanically characterized and compared to the results of witness samples. The materials used were IN718 and IN738LC. The Ni superalloy IN738LC is challenging to process using PBF-LB/M due to its crack susceptibility. Although the mechanical properties are promising for high temperature applications, PBF-LB/M IN738LC is not yet commonly used in application. In comparison, PBF-LB/M IN718 is already used in high temperature applications. Microstructural differences regarding phase formation and distribution were found between witness and extracted samples and are attributed to the difference in solidification conditions during the PBF-LB/M process itself. The grain sizes differ, with the largest grain size found in the witness samples. The samples extracted from the SEC show smaller grains. The difference in grain sizes also causes differences in mechanical properties. The Vickers hardness of extracted samples is higher compared to witness samples. The tensile and yield strengths of the extracted samples are significantly higher than those of witness samples. The IN738LC creep properties differ from those of IN718 due to phase formation and different creep deformation mechanisms taking plac

Investigation of oxygen permeation through composites of PMMA and surface-modified ZnO nanoparticles

Oxygen permeabilities of nanocomposite films consisting of poly(methyl methacrylate) (PMMA) and different amounts of spherical zinc oxide (ZnO) nanoparticles were determined to investigate the barrier effect of this material with respect to particle content. A method was applied which is based on quenching of an excited phosphorescent dye by oxygen. Possible effects of the nanoparticles on the response of the dye molecules were investigated and were ruled out

Hydrogen-Bonding Organocatalysis Enabled Photocatalytic Intramolecular [2+2]-Cycloaddition Reaction

The combination of organocatalytic activation and photocatalysis for enabling the intramolecular [2+2]‐cycloaddition of enone‐ene substrates bearing one Lewis base binding site is reported. While in a variety of solvents a poor conversion or no reaction takes place in the absence of a hydrogen bonding catalyst, the corresponding ring‐fused cyclobutane products could be built in moderate to good yields using a synergistic dual iridium‐urea co‐catalytic system. Control and mechanistic studies supported the postulated interaction between the organocatalyst and the substrate, which proved essential for an efficient energy transfer from the photosensitizer

The cytotoxic effect and glucose uptake modulation of Baeckea frutescens on breast cancer cells

Background: Baeckea frutescens (B. frutescens) of the family Myrtaceae is a plant that has been used in traditionalmedicine. It is known to have antibacterial, antipyretic and cytoprotective properties. The objective of this study isto explore the mechanism of B. frutescens leaves extracts in eliminating breast cancer cells. Method: B. frutescens leaves extracts were prepared using Soxhlet apparatus with solvents of different polarity. The selective cytotoxicity of these extracts at various concentrations (20 to 160 μg/ml) were tested using cell viability assay after 24, 48 and 72 h of treatment. The IC50 value in human breast cancer (MCF-7 and MDA-MB-231) and mammary breast (MCF10A) cell lines were determined. Apoptotic study using AO/PI double staining was performed using fluorescent microscope. The glucose uptake was measured using 2-NBDG, a fluorescent glucose analogue. The phytochemical screening was performed for alkaloids, flavonoids, tannins, triterpenoids, and phenols. Results: B. frutescens leaves extracts showed IC50 value ranging from 10 -127μg/ml in MCF-7 cells after 72 h of treatment. Hexane extract had the lowest IC50 value (10μg/ml), indicating its potent selective cytotoxic activity. Morphology of MCF-7 cells after treatment with B. frutescens extracts exhibited evidence of apoptosis that included membrane blebbing and chromatin condensation. In the glucose uptake assay, B. frutescens extracts suppressed glucose uptake in cancer cells as early as 24 h upon treatment. The inhibition was significantly lower compared to the positive control WZB117 at their respective IC50 value after 72 h incubation. It was also shown that the glucose inhibition is selective towards cancer cells compared to normal cells. The phytochemical analysis of the extract using hexane as the solvent in particular gave similar quantities of tannin, triterpenoids, flavonoid and phenols. Presumably, these metabolites have a synergistic effect in the in vitro testing, producing the potent IC50 value and subsequently cell death. Conclusion: This study reports the potent selective cytotoxic effect of B. frutescens leaves hexane extract against MCF-7 cancer cells. B. frutescens extracts selectively suppressed cancer cells glucose uptake and subsequently induced cancer cell death. These findings suggest a new role of B. frutescens in cancer cell metabolis

Cholesterol accumulation in macrophages drives NETosis in atherosclerotic plaques via IL-1β secretion

OBJECTIVE: Neutrophil extracellular trap formation (NETosis) increases atherosclerotic plaque vulnerability and athero-thrombosis. However, mechanisms promoting NETosis during atherogenesis are poorly understood. We have shown that cholesterol accumulation due to myeloid cell deficiency of the cholesterol transporters ATP Binding Cassette A1 and G1 (ABCA1/G1) promotes NLRP3 inflammasome activation in macrophages and neutrophils and induces prominent NETosis in atherosclerotic plaques. We investigated whether NETosis is a cell intrinsic effect in neutrophils or is mediated indirectly by cellular crosstalk from macrophages to neutrophils involving IL-1β.METHODS AND RESULTS: We generated mice with neutrophil or macrophage-specific Abca1/g1 deficiency (S100A8CreAbca1fl/flAbcg1fl/fl or CX3CR1CreAbca1fl/flAbcg1fl/fl mice, respectively), and transplanted their bone marrow into low-density lipoprotein receptor knockout mice. We then fed the mice a cholesterol-rich diet. Macrophage, but not neutrophil Abca1/g1 deficiency activated inflammasomes in macrophages and neutrophils, reflected by caspase-1 cleavage, and induced NETosis in plaques. NETosis was suppressed by administering an interleukin (IL)-1β neutralizing antibody. The extent of NETosis in plaques correlated strongly with the degree of neutrophil accumulation, irrespective of blood neutrophil counts, and neutrophil accumulation was decreased by IL-1β antagonism. In vitro, IL-1β or media transferred from Abca1/g1 deficient macrophages increased NETosis in both control and Abca1/Abcg1 deficient neutrophils. This cell-extrinsic effect of IL-1β on NETosis was blocked by an NLRP3 inhibitor.CONCLUSIONS: These studies establish a new link between inflammasome mediated IL-1β production in macrophages and NETosis in atherosclerotic plaques. Macrophage-derived IL-1β appears to increase NETosis both by increasing neutrophil recruitment to plaques and by promoting neutrophil NLRP3 inflammasome activation.</p

Simulation of cyclic deformation behavior of selective laser melted and hybrid-manufactured aluminum alloys using the phase-field method

Selective laser melting process has already been developed for many metallic materials, including steel, aluminum, and titanium. The quasistatic properties of these materials have been found to be comparable or even better than their conventionally-manufactured counterparts; however, for their reliable applications in operational components, their fatigue behavior plays a critical role, which is dominated by several process-related features, like surface roughness, remnant porosity, microstructure, and residual stresses, which are controlled by the processing features, like imparted energy density to the material, its corresponding solidification behavior, the cooling rate in the process, as well as post-processing treatments. This study investigates the influence of these parameters on the cyclic deformation behavior of selective laser melted as well as hybrid-manufactured aluminum alloys. The corresponding microstructural features and porosity conditions are evaluated for developing correlations between the process conditions to microstructure, the deformation behavior, and the corresponding fatigue lives. From the numerical point of view, damage development with respect to process-induced cyclic deformation behavior is assessed by the phase-field method, which has been identified as an appropriate method for the determination of fatigue life at the respective applied stress levels. Fatigue strength of SLM-processed parts is found better than their cast counterparts, while hybridization has further increased fatigue strength. No effect of test frequency on the fatigue life could be established