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Using first-principles theory, we investigated the most stable configuration for the Rh dopant on a MoSe2 monolayer, and the interaction of the Rh-doped MoSe2 (Rh-MoSe2) monolayer with four toxic gases (CO, NO, NO2 and SO2) to exploit the potential application of the Rh-MoS2 monolayer as a gas sensor or adsorbent.

The insulation characteristics and decomposition components of C4F7N/N2 gas mixture, a potential substitute for SF6, were first explored by breakdown experiments/gas chromatography–mass spectrometer. The structural properties of C4F7N molecule and the decomposition mechanism of C4F7N/N2 gas mixture were analyzed based on the density functional theory calculation and ReaxFF molecular dynamics simulation. We found that C4F7N/N2 mixture has great self-recovery performance. The decomposition of C4F7N in a discharge mainly produces CF4, C2F6, C3F8, CF3CN, C2F4, C3F6, and C2F5CN, among which the relative content of C2F6, CF4, and CF3CN is higher. ReaxFF-MD simulations show that CF3, CN, F, and C3F7 are the four main free radicals produced by C4F7N. The decomposition characteristics of N2 are better than that of C4F7N. The addition of N2 has a certain buffering effect to avoid the massive decomposition of C4F7N. The global warming potential value of a gas mixture containing 20% C4F7N decreased by 94.32% compared with SF6. Relevant results not only reveal the decomposition characteristics of C4F7N/N2 mixture in a discharge comprehensively, but also provide a reference for engineering application and emission of a C4F7N/N2 gas mixture.

Intrinsic carbon nanotubes (CNTs) show limited toxic gas detection, thus, we need to develop a method to fabricate a novel CNT sensor that has good sensitivity. In this study, density functional theory (DFT) was applied to determine the adsorption behavior of Au-doped singlewalled carbon nanotubes (Au-SWCNTs) to SO 2 and H 2 S. The calculated results show that Au-SWCNTs have a high sensitivity to SO 2 and H 2 S. When SO 2 adsorbs on the surface of the nanotube, a large number of electrons transfer from the Au-SWCNT to SO 2 , which results in a decrease in the frontier orbital energy gap and an increase in electrical conductivity. On the other hand, when H 2 S adsorbs on the surface of the nanotube, the electrons transfer from H 2 S to the Au-SWCNT, the frontier orbital energy gap increases, and the electrical conductivity decreases. Thus, SO 2 and H 2 S could be detected by Au-SWCNTs. This conclusion is useful for the development of CNT-based gas sensors and provides a theoretical basis to fabricate Au-SWCNT-based gas sensors.

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We isolated cDNAs that encode a 77-kDa peptide similar to repeats 10 -16 of ␤-spectrins. Its gene localizes to human chromosome 19q13.13-q13.2 and mouse chromosome 7, at 7.5 centimorgans. A 289-kDa isoform, similar to full-length ␤-spectrins, was partially assembled from sequences in the human genomic DNA data base and completely cloned and sequenced. RNA transcripts are seen predominantly in the brain, and Western analysis shows a major peptide that migrates as a 72-kDa band. This new gene, spectrin ␤IV, thus encodes a full-length minor isoform (Sp␤IV⌺1) and a truncated major isoform (Sp␤IV⌺5). Immunostaining of cells shows a micropunctate pattern in the cytoplasm and nucleus. In mesenchymal stem cells, the staining concentrates at nuclear dots that stain positively for the promyelocytic leukemia protein (PML). Expression of Sp␤IV⌺5 fused to green fluorescence protein in cells produces nuclear dots that include all PML bodies, which double in number in transfected cells. Deletion analysis shows that partial repeats 10 and 16 of Sp␤IV⌺5 are necessary for nuclear dot formation. Immunostaining of whole-mount nuclear matrices reveals diffuse positivity with accentuation at PML bodies. Spectrin ␤IV is the first ␤-spectrin associated with a subnuclear structure and may be part of a nuclear scaffold to which gene regulatory machinery binds.Spectrin is an important component of the membrane skeleton attached to the inner leaf of the lipid bilayer of plasma membranes. First described in the erythrocyte (1), spectrins are found in all or almost all cells (2-4). In erythrocytes, an intact spectrin-based membrane skeleton is critical for the structural integrity of the plasma membrane. Defects in its components are associated with red cell fragility and premature destruction in the human diseases hereditary spherocytosis and elliptocytosis and their animal models (5). The function of a spectrin-based plasma membrane skeleton in non-erythroid tissues is less well defined, but it is hypothesized to be important in establishing and maintaining the asymmetric distribution of proteins in specialized plasma membrane domains, particularly in polarized cells (6).Recently, components of a spectrin-based membrane skeleton have also been found in several intracellular organelles. Isoforms of spectrin and ankyrin exist in Golgi membranes (7-9), lysosomal membranes (10), and secretory vesicles (11)(12)(13)(14). Spectrin also associates with actin-related protein 1 (centractin), a subunit of the dynactin complex, which associates with dynein and transports vesicles along microtubules in the secretory pathway (15). A spectrin-based membrane skeleton attached to intracellular organelles may provide a structural framework to anchor the vesicular transport machinery (16 -19). The potential role of a spectrin-based membrane skeleton in the nucleus is unclear. There are interesting recent reports indicating that spectrin ␣II is part of a nuclear protein complex involved in repair of DNA interstrand cross-links (20 -22). Whether ␣II-spectrin b...

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