Investigation of phase transformations and corrosion resistance in Co/CoCo2O4 nanowires and their potential use as a basis for lithium-ion batteries

The paper is devoted to the study of the effect of thermal annealing on the change in the structural properties and phase composition of metal Co nanostructures, as well as the prospects of their use as anode materials for lithium-ion batteries. During the study, a four-stage phase transition in the structure of nanowires consisting of successive transformations of the structure (Со-FCC/Co-HCP) → (Со-FCС) → (Со-FCC/СоСо2О4) → (СоСо2О4), accompanied by uniform oxidation of the structure of nanowires with an increase in temperature above 400 °C. In this case, an increase in temperature to 700 °C leads to a partial destruction of the oxide layer and surface degradation of nanostructures. During life tests, it was found that the lifetime for oxide nanostructures exceeds 500 charge/discharge cycles, for the initial nanostructures and annealed at a temperature of 300 °С, the lifetimes are 297 and 411 cycles, respectively. The prospects of using Co/CoCo2O4 nanowires as the basis for lithium-ion batteries is shown. © 2019, The Author(s)

Mutations in the Neuronal Vesicular SNARE VAMP2 Affect Synaptic Membrane Fusion and Impair Human Neurodevelopment

VAMP2 encodes the vesicular SNARE protein VAMP2 (also called synaptobrevin-2). Together with its partners syntaxin-1A and synaptosomal-associated protein 25 (SNAP25), VAMP2 mediates fusion of synaptic vesicles to release neurotransmitters. VAMP2 is essential for vesicular exocytosis and activity-dependent neurotransmitter release. Here, we report five heterozygous de novo mutations in VAMP2 in unrelated individuals presenting with a neurodevelopmental disorder characterized by axial hypotonia (which had been present since birth), intellectual disability, and autistic features. In total, we identified two single-amino-acid deletions and three non-synonymous variants affecting conserved residues within the C terminus of the VAMP2 SNARE motif. Affected individuals carrying de novo non-synonymous variants involving the C-terminal region presented a more severe phenotype with additional neurological features, including central visual impairment, hyperkinetic movement disorder, and epilepsy or electroencephalography abnormalities. Reconstituted fusion involving a lipid-mixing assay indicated impairment in vesicle fusion as one of the possible associated disease mechanisms. The genetic synaptopathy caused by VAMP2 de novo mutations highlights the key roles of this gene in human brain development and function

Mutations in the Neuronal Vesicular SNARE VAMP2 Affect Synaptic Membrane Fusion and Impair Human Neurodevelopment

VAMP2 encodes the vesicular SNARE protein VAMP2 (also called synaptobrevin-2). Together with its partners syntaxin-1A and synaptosomal-associated protein 25 (SNAP25), VAMP2 mediates fusion of synaptic vesicles to release neurotransmitters. VAMP2 is essential for vesicular exocytosis and activity-dependent neurotransmitter release. Here, we report five heterozygous de novo mutations in VAMP2 in unrelated individuals presenting with a neurodevelopmental disorder characterized by axial hypotonia (which had been present since birth), intellectual disability, and autistic features. In total, we identified two single-amino-acid deletions and three non-synonymous variants affecting conserved residues within the C terminus of the VAMP2 SNARE motif. Affected individuals carrying de novo non-synonymous variants involving the C-terminal region presented a more severe phenotype with additional neurological features, including central visual impairment, hyperkinetic movement disorder, and epilepsy or electroencephalography abnormalities. Reconstituted fusion involving a lipid-mixing assay indicated impairment in vesicle fusion as one of the possible associated disease mechanisms. The genetic synaptopathy caused by VAMP2 de novo mutations highlights the key roles of this gene in human brain development and function

Reply to Comment on 'New ways of developing glass conducting glass CdS/CdTe metal thin-film solar cells based on a new model', by Dharmadasa et al 2002 Semicond. Sci. Technol 17 1238-48

A high short-circuit current density of 69.1 mA cm(-2) for silicon solar cells was first published over a decade ago. A few photovoltaic research groups dismissed that report indicating errors must have been made in measurement. Our work on both CdTe and CIGS based tandem solar cells has also shown similar high current densities and provides one possible explanation for the observations on silicon solar cells. This paper identifies the urgent need for theoretical calculations for multilayer graded bandgap tandem solar cells

Experimental study of graded bandgap Cu(InGa)(SeS)(2) thin films grown on glass/molybdenum substrates by selenization and sulphidation

High-performance Cu(InGa)(SeS)(2) (CIGSS) thin film absorbers with an intentionally graded bandgap structure grown by a two-stage method have been studied. Materials obtained from Showa Shell Sekiyu K.K., Japan have been grown using selenization and sulphidation of the Mo/Cu-Ga/In stacked precursors. Full characterizations have been carried out using X-ray diffraction, Raman, scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy (XPS), X-ray fluorescence, inductively coupled plasma mass spectroscopy, glow discharge optical emission spectroscopy (GDOES) and photoelectrochemical (PEC) techniques to study various properties. The material layers were found to be polycrystalline with the (112) preferred orientation, and the largest grains were about 2 mum. Raman measurements show the presence of at least five different phases within the material. XPS confirmed the copper depletion and the richness of sulphur at the top surface region. Although the PEC studies indicate the overall electrical conductivity of the layer as p-type, GDOES profiling reveals the segregation of different phases at different depths suggesting the possibility of having buried junctions within the material itself. The results are presented together with suggestions for further improvements of CIGSS solar cell material. (C) 2004 Elsevier B.V. All rights reserved