In order to clarify the role of R2O3 in the metal-oxide catalysts derived from complex oxide precursors, a series of R1.5Ca0.5NiO4 (R = Nd, Sm, Eu) complex oxides was obtained. A significant ...systematic increase in the orthorhombic distortion of the R1.5Ca0.5NiO4 structure (K2NiF4 type, Cmce) from Nd to Eu correlates with a corresponding decrease in their ionic radii. A reduction of R1.5Ca0.5NiO4 in the Ar/H2 gas mixture at 800 °C causes a formation of dense agglomerates of CaO and R2O3 coated with spherical 25–30 nm particles of Ni metal. The size of metal particles and oxide agglomerates is similar in all Ni/(R2O3,CaO) composites in the study. Their morphology is rather similar to the products of redox exsolution obtained by the partial reduction of complex oxides. All obtained composites demonstrated a significant catalytic activity in the dry reforming (DRM) and partial oxidation (POM) of methane at 700–800 °C. A systematic decrease in the DRM catalytic activity of composites from Nd to Eu could be attributed to the basicity reduction of R2O3 components of the composite catalysts. The maximum CH4 conversion in POM reaction was observed for Ni/(Sm2O3,CaO), while the maximum selectivity was demonstrated by Nd2O3-based composite. The possible reasons for the observed difference are discussed.
Solid solutions Nd2−xSrxNiO4±δ (x = 0, 0.5, 1, 1.2, 1.4) with a K2NiF4 structure can be obtained from freeze-dried precursors. The end members of this series can be obtained at T ≥ 1000 °C only, ...while complex oxides with x = 1; 1.5 are formed at T ≥ 700 °C. Thermal analysis revealed the two stages of Nd2−xSrxNiO4±δ thermal reduction in a 10%H2/Ar gas mixture that was completed at 900 °C. For x < 0.2, the reduction products demonstrated an exsolution-like morphology with Ni nanoparticles allocated at the surface of oxide grains. As-obtained nanocomposites with x = 0 and x > 1 revealed the outstanding catalytic activity and selectivity in the dry reforming of the methane (DRM) reaction at 800 °C with CH4 conversion close to the thermodynamic values. The appearance of two different maxima of the catalytic properties of Ni/(Nd2O3,SrCO3) nanocomposites could be affiliated with the domination of the positive contributions of Nd2O3 and SrCO3, respectively.
The origin and early dispersal of speakers of Transeurasian languages-that is, Japanese, Korean, Tungusic, Mongolic and Turkic-is among the most disputed issues of Eurasian population history
. A key ...problem is the relationship between linguistic dispersals, agricultural expansions and population movements
. Here we address this question by 'triangulating' genetics, archaeology and linguistics in a unified perspective. We report wide-ranging datasets from these disciplines, including a comprehensive Transeurasian agropastoral and basic vocabulary; an archaeological database of 255 Neolithic-Bronze Age sites from Northeast Asia; and a collection of ancient genomes from Korea, the Ryukyu islands and early cereal farmers in Japan, complementing previously published genomes from East Asia. Challenging the traditional 'pastoralist hypothesis'
, we show that the common ancestry and primary dispersals of Transeurasian languages can be traced back to the first farmers moving across Northeast Asia from the Early Neolithic onwards, but that this shared heritage has been masked by extensive cultural interaction since the Bronze Age. As well as marking considerable progress in the three individual disciplines, by combining their converging evidence we show that the early spread of Transeurasian speakers was driven by agriculture.
In order to clarify the role of Rsub.2Osub.3 in the metal-oxide catalysts derived from complex oxide precursors, a series of Rsub.1.5Casub.0.5NiOsub.4 (R = Nd, Sm, Eu) complex oxides was obtained. A ...significant systematic increase in the orthorhombic distortion of the Rsub.1.5Casub.0.5NiOsub.4 structure (Ksub.2NiFsub.4 type, Cmce) from Nd to Eu correlates with a corresponding decrease in their ionic radii. A reduction of Rsub.1.5Casub.0.5NiOsub.4 in the Ar/Hsub.2 gas mixture at 800 °C causes a formation of dense agglomerates of CaO and Rsub.2Osub.3 coated with spherical 25-30 nm particles of Ni metal. The size of metal particles and oxide agglomerates is similar in all Ni/(Rsub.2Osub.3,CaO) composites in the study. Their morphology is rather similar to the products of redox exsolution obtained by the partial reduction of complex oxides. All obtained composites demonstrated a significant catalytic activity in the dry reforming (DRM) and partial oxidation (POM) of methane at 700-800 °C. A systematic decrease in the DRM catalytic activity of composites from Nd to Eu could be attributed to the basicity reduction of Rsub.2Osub.3 components of the composite catalysts. The maximum CHsub.4 conversion in POM reaction was observed for Ni/(Smsub.2Osub.3,CaO), while the maximum selectivity was demonstrated by Ndsub.2Osub.3-based composite. The possible reasons for the observed difference are discussed.
Schizophrenia is considered a multifactorial disease, where one of the pathogenetic links is oxidative stress; however, the results of studies are often contradictory, largely due to significant ...heterogeneity among study methods. The present study was undertaken to compare the levels of oxidative stress markers in the peripheral blood of patients with a first episode of schizophrenia (FES) and in healthy volunteers (HV). The study included 50 patients with FES and 37 HV. Blood samples were collected for spectrophotometric assessment of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), aldehyde-2,4-dinitrophenylhydrazone (ADNPH), and ketone-2,4-dinitrophenylhydrazone (KDNPH) in blood plasma. Results showed that in patients with FES compared with HV, a significant decrease in CAT activity and an increase in oxidative modification of proteins (OMP) were found. In both groups, a significant increase in the level of MDA with age was revealed. In patients, the GSH plasma level was inversely proportional to the ADNPH level, and SOD activity was directly proportional to the KDNPH level. In volunteers there was no such correlation; however, there was a direct correlation between CAT activity and the levels of OMP and MDA. In both groups, a moderate direct correlation between peroxidation products was observed. The results confirm that a redox imbalance (a deficiency of antioxidants, in particular CAT, and excess OMP) may be a pathogenetic link in schizophrenia, which is manifested already at an early stage of the disease.
Solid solutions Ndsub.2−xSrsub.xNiOsub.4±δ (x = 0, 0.5, 1, 1.2, 1.4) with a Ksub.2NiFsub.4 structure can be obtained from freeze-dried precursors. The end members of this series can be obtained at T ...≥ 1000 °C only, while complex oxides with x = 1; 1.5 are formed at T ≥ 700 °C. Thermal analysis revealed the two stages of Ndsub.2−xSrsub.xNiOsub.4±δ thermal reduction in a 10%Hsub.2/Ar gas mixture that was completed at 900 °C. For x < 0.2, the reduction products demonstrated an exsolution-like morphology with Ni nanoparticles allocated at the surface of oxide grains. As-obtained nanocomposites with x = 0 and x > 1 revealed the outstanding catalytic activity and selectivity in the dry reforming of the methane (DRM) reaction at 800 °C with CHsub.4 conversion close to the thermodynamic values. The appearance of two different maxima of the catalytic properties of Ni/(Ndsub.2Osub.3,SrCOsub.3) nanocomposites could be affiliated with the domination of the positive contributions of Ndsub.2Osub.3 and SrCOsub.3, respectively.
Aryl hydrocarbon receptor (AHR) is the key transcription factor that controls animal development and various adaptive processes. The AHR's target genes are involved in biodegradation of endogenous ...and exogenous toxins, regulation of immune response, organogenesis, and neurogenesis. Ligand binding is important for the activation of the AHR signaling pathway. Invertebrate AHR homologs are activated by endogenous ligands whereas vertebrate AHR can be activated by both endogenous and exogenous ligands (xenobiotics). Several studies using mammalian cultured cells have demonstrated that transcription of the AHR target genes can be activated by exogenous AHR ligands, but little is known about the effects of AHR in a living organism. Here, we examined the effects of human AHR and its ligands using transgenic
lines with an inducible human
gene. We found that exogenous AHR ligands can increase as well as decrease the transcription levels of the AHR target genes, including genes that control proliferation, motility, polarization, and programmed cell death. This suggests that AHR activation may affect the expression of gene networks that could be critical for cancer progression and metastasis. Importantly, we found that AHR target genes are also controlled by the enzymes that modify chromatin structure, in particular components of the epigenetic Polycomb Repressive complexes 1 and 2. Since exogenous AHR ligands (alternatively - xenobiotics) and small molecule inhibitors of epigenetic modifiers are often used as pharmaceutical anticancer drugs, our findings may have significant implications in designing new combinations of therapeutic treatments for oncological diseases.
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