65 research outputs found
'She's like a daughter to me': insights into care, work and kinship from rural Russia
This article draws on ethnographic research into a state-funded homecare service in rural Russia. The article discusses intersections between care, work and kinship in the relationships between homecare workers and their elderly wards and explores the ways in which references to kinship, as a means of authenticating paid care and explaining its emotional content, reinforce public and private oppositions while doing little to relieve the tensions and conflicts of care work. The discussion brings together detailed empirical insights into local ideologies and practices as a way of generating new theoretical perspectives, which will be of relevance beyond the particular context of study
The Study on Thermal Expansion of Ceramic Composites with Addition of ZrW[2]O]8]
The studies on structure, phase composition and thermal properties of (Al[2]O[3] - 20 wt% ZrO[2]) - ZrW[2]O[8] ceramic composites obtained using nanosized, initial powders were conducted. Homogeneously distributed white particles on the polished surface of composites were observed. Phase composition of the composites was represented with corundum, monoclinic ZrO[2] and two modifications of ZrW[2]O[8] (tetragonal and cubic). Linear thermal expansion coefficient values of the composites were determined. The difference in experimental and calculated coefficient of thermal expansion values for composites obtained may be attributed to phase transformations, features of the structure, internal stresses due to thermal expansion mismatch, which contribute significantly to thermal expansion of the ceramic composites
Structure and thermal behavior of zirconium tungstate under heating
The morphology and properties of powders ZrW2O7(OH)[2]•2H[2]O and ZrW[2]O[8], obtained under the conditions of hydrothermal synthesis was studied. Using the high-temperature X-ray analysis, the mechanism of formation of zirconium tungstate was established. The influence of temperature on the structure and properties of materials was studied using shadow-casting method
W- rich mixed oxide solid solutions under pressure
We report high-pressure synchrotron X-ray powder diffraction data for the W-rich cubic ZrW[2-x]Mo[x]O[8] (x=0.4) up to 10 GPa with open decompression. This study shows that cubic- ZrW[1.6]Mo[0.4]O[8] transforms to orthorhombic phase at the 5.04 GPa. Pressure-induced reversable amorphization of material was observed at 8.13 GPa. The obtained data suggest that W-rich cubic ZrW[2-x]Mo[x]O[8] (x=0.4) solid solutions are more attractive for creating products working under extreme conditions and mechanic stress
ZnO Nanorods via Spray Deposition of Solutions Containing Zinc Chloride and Thiocarbamide
In this work we present the results on formation of ZnO nanorods prepared by spray of aqueous solutions containing ZnCl2and thiocarbamide (tu) at different molar ratios. It has been observed that addition of thiocarbamide into the spray solution has great impact on the size, shape and phase composition of the ZnO crystals. Obtained layers were characterized by scanning electron microscopy (SEM) equipped with energy selected backscattered electron detection system (ESB), X-ray diffraction (XRD) and photoluminescence spectroscopy (PL). Small addition of thiocarbamide into ZnCl2solution (ZnCl2:tu = 1:0.25) supports development of significantly thinner ZnO nanorods with higher aspect ratio compared to those obtained from ZnCl2solution. Diameter of ZnO rods decreases from 270 to 100 nm and aspect ratio increases from ∼2.5 to 12 spraying ZnCl2and ZnCl2:tu solutions, respectively. According to XRD, well crystallized (002) orientated pure wurtzite ZnO crystals have been formed. However, tiny ‘spot’—like formations of ZnS were detected on the side planes of hexagonal rods prepared from the thiocarbamide containing solutions. Being adsorbed on the side facets of the crystals ZnS inhibits width growth and promotes longitudinalc-axis growth
Genome polymorphism of the synthetic species xTrititrigia cziczinii Tsvel. inferred from AFLP analysis
×Trititrigia cziczinii Tsvel. is a synthetic species obtained as a result of hybridization of different wheat and wheat- grass species. ×T. cziczinii has unique characteristics, as it is a perennial species, with the ability to grow after mowing, high adaptability, resistance to diseases and pests, high protein and gluten content in the grain. All this makes it a promising new crop for agriculture. The new species is a good object for fundamental research in the field of genetics, phylogeny and evolution of cereals (Poaceae). However, there were practically no genetic studies of ×T. cziczinii. The aim of this work was to study the genetic diversity of 24 representatives of two ×T. cziczinii subspecies (ssp. Submitans and ssp. Perenne). To estimate interspecific differences, 17 samples of other tribe Triticeae species (Triticum aestivum, Triticum durum, Agropyron glaucum and Agropyron elon gatum, as well as samples of Triticum-Agropyron and TriticumElymus hybrids) were included in the analysis. For the study, AFLP method (Amplified Fragment Length Polymorphism) was chosen, which allowed us to reveal a sufficiently high polymorphism level of the studied samples. The two primer/enzyme combinations (EcoRI-ACT/MseI-CCC, EcoRI-ACT/MseI-CTA) allow ed the iden tification of 227 fragments, 224 of them were polymorphic (98.68 %), and the level of intraspecific polymorphism of 24 ×T. cziczinii samples was 68.15 %. The iden tified fragments of AFLP spectra, specific for the ×T. cziczinii representatives and the studied wheatgrass species, can be the basis for creating markers that will detect introgressions of genetic material of the genus Agropyron in the T. cziczinii ge nome. Our results indicate a greater genetic relatedness of ×T. cziczinii to T. aestivum than to representatives of the genus Agropyron. According to the cluster analysis, representatives of ×T. cziczinii and varieties of bread wheat were combined into a single subcluster, within which the samples of two species form separate groups. At the same time, the evaluation of the intraspecific genetic diversity of ×T. cziczinii showed no reliable differentiation of representatives of the subspecies Submitans and Perenne, which is probably due to uncertain genetic nature of perenniality, the main feature that divides these subspecies. The study of the unique ×T. cziczinii collection allowed us to obtain the first data on the genetics of the species, while previous studies were focused mainly on phenotypic and economically valuable traits. AFLP analysis used in this study showed high efficiency when working with less studied species, and its results are promising and useful for understanding the genetic structure of the new species (×T. cziczinii Tsvel.)
Synthesis and Characterization of ZnO Nanorods and Nanodisks from Zinc Chloride Aqueous Solution
ZnO nanorods and nanodisks were synthesized by solution process using zinc chloride as starting material. The morphology of ZnO crystal changed greatly depending on the concentrations of Zn2+ion and ethylene glycohol (EG) additive in the solution. The effect of thermal treatment on the morphology was investigated. Photocatalytic activities of plate-like Zn5(OH)8Cl2 · H2O and rod-like ZnO were characterized. About 18% of 1 ppm NO could be continuously removed by ZnO particles under UV light irradiation
Nanometer Sized Silver Particles Embedded Silica Particles—Spray Method
Spherical shaped, nanometer to micro meter sized silica particles were prepared in a homogeneous nature by spray technique. Silver nanoparticles were produced over the surface of the silica grains in a harmonized manner. The size of silver and silica particles was effectively controlled by the precursors and catalysts. The electrostatic repulsion among the silica spheres and the electro static attraction between silica spheres and silver particles make the synchronized structure of the synthesized particles and the morphological images are revealed by transmission electron microscope. The silver ions are reduced by sodium borohydride. Infra red spectroscopy and X-ray photoelectron spectroscopy analysis confirm the formation of silver–silica composite particles. Thermal stability of the prepared particles obtained from thermal analysis ensures its higher temperature applications. The resultant silver embedded silica particles can be easily suspended in diverse solvents and would be useful for variety of applications
NADPH oxidase and reactive oxygen species contribute to alcohol-induced microglial activation and neurodegeneration
<p>Abstract</p> <p>Background</p> <p>Activation of microglia causes the production of proinflammatory factors and upregulation of NADPH oxidase (NOX) that form reactive oxygen species (ROS) that lead to neurodegeneration. Previously, we reported that 10 daily doses of ethanol treatment induced innate immune genes in brain. In the present study, we investigate the effects of chronic ethanol on activation of NOX and release of ROS, and their contribution to ethanol neurotoxicity.</p> <p>Methods</p> <p>Male C57BL/6 and NF-κB enhanced GFP mice were treated intragastrically with water or ethanol (5 g/kg, i.g., 25% ethanol w/v) daily for 10 days. The effects of chronic ethanol on cell death markers (activated caspase-3 and Fluoro-Jade B), microglial morphology, NOX, ROS and NF-κB were examined using real-time PCR, immunohistochemistry and hydroethidine histochemistry. Also, Fluoro-Jade B staining and NOX gp91<sup>phox </sup>immunohistochemistry were performed in the orbitofrontal cortex (OFC) of human postmortem alcoholic brain and human moderate drinking control brain.</p> <p>Results</p> <p>Ethanol treatment of C57BL/6 mice showed increased markers of neuronal death: activated caspase-3 and Fluoro-Jade B positive staining with Neu-N (a neuronal marker) labeling in cortex and dentate gyrus. The OFC of human post-mortem alcoholic brain also showed significantly more Fluoro-Jade B positive cells colocalized with Neu-N, a neuronal marker, compared to the OFC of human moderate drinking control brain, suggesting increased neuronal death in the OFC of human alcoholic brain. Iba1 and GFAP immunohistochemistry showed activated morphology of microglia and astrocytes in ethanol-treated mouse brain. Ethanol treatment increased NF-κB transcription and increased NOX gp91<sup>phox </sup>at 24 hr after the last ethanol treatment that remained elevated at 1 week. The OFC of human postmortem alcoholic brain also had significant increases in the number of gp91<sup>phox </sup>+ immunoreactive (IR) cells that are colocalized with neuronal, microglial and astrocyte markers. In mouse brain ethanol increased gp91<sup>phox </sup>expression coincided with increased production of O<sub>2</sub><sup>- </sup>and O<sub>2</sub><sup>- </sup>- derived oxidants. Diphenyleneiodonium (DPI), a NOX inhibitor, reduced markers of neurodegeneration, ROS and microglial activation.</p> <p>Conclusions</p> <p>Ethanol activation of microglia and astrocytes, induction of NOX and production of ROS contribute to chronic ethanol-induced neurotoxicity. NOX-ROS and NF-κB signaling pathways play important roles in chronic ethanol-induced neuroinflammation and neurodegeneration.</p
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