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1.
A full-length cDNA clone for a progesterone membrane binding protein from porcine vascular smooth muscle cells was isolated and the complete nucleotide sequence determined. The cDNA encodes a protein of 194 amino acids with a transmembrane segment. This protein is likely to represent the first steroid membrane receptor or a part of it for which sequence information is available.  相似文献   
2.
Inhalational anesthetics was previously reported to suppress glioma cell malignancy but underlying mechanisms remain unclear. The present study aims to investigate the effects of sevoflurane and desflurane on glioma cell malignancy changes via microRNA (miRNA) modulation. The cultured H4 cells were exposed to 3.6% sevoflurane or 10.3% desflurane for 2 h. The miR-138, -210 and -335 expression were determined with qRT-PCR. Cell proliferation and migration were assessed with wound healing assay, Ki67 staining and cell count kit 8 (CCK8) assay with/without miR-138/-210/-335 inhibitor transfections. The miRNA downstream proteins, hypoxia inducible factor-1α (HIF-1α) and matrix metalloproteinase 9 (MMP9), were also determined with immunofluorescent staining. Sevoflurane and desflurane exposure to glioma cells inhibited their proliferation and migration. Sevoflurane exposure increased miR-210 expression whereas desflurane exposure upregulated both miR-138 and miR-335 expressions. The administration of inhibitor of miR-138, -210 or -335 inhibited the suppressing effects of sevoflurane or desflurane on cell proliferation and migration, in line with the HIF-1α and MMP9 expression changes. These data indicated that inhalational anesthetics, sevoflurane and desflurane, inhibited glioma cell malignancy via miRNAs upregulation and their downstream effectors, HIF-1α and MMP9, downregulation. The implication of the current study warrants further study.  相似文献   
3.
The sol-gel process for the hydrolysis and polycondensation of tin tetra-n-butoxide in butanol was followed by viscosity measurements. The precipitation of tin-containing ultrafine particles was observed without any variation in the solution viscosity in the absence of diethylene glycols, while the viscosity increase was made without any precipitation by the addition of diethylene glycol. The induction period and the rate of the viscosity increase after the induction period was independent of the diethylene glycol content but depended upon the water content. The Monte Carlo simulation data were consistent with data for the viscosity experiment. The simulation was based on a kinetic model of the slow hydrolysis of tin tetra-n-butoxide, the reverse reaction of hydrolysis, and the polycondensation of the hydroxy derivatives.  相似文献   
4.
We have reported that the transistors having the c‐axis‐aligned crystalline (CAAC) In‐Ga‐Zn oxide (IGZO) show good performance. Recently, In‐Sn‐Zn Oxide (ITZO) has attracted much attention because of its high electron mobility, as well as IGZO. However, it has been reported that ITZO field effect transistors (FET) tend to have positive Vth (normally‐on characteristics) and poor reliability compared with IGZO‐FETs. We have reported that high‐performance and high‐reliability OS‐FETs can be fabricated by using CAAC‐IGZO, which has high crystallinity and has no clear grain boundaries, as an active layer. Therefore, we have fabricated CAAC‐ITZO thin films to improve performance of ITZO‐FETs by using CAAC‐ITZO as an active layer. In addition, FETs employing CAAC‐ITZO have better characteristics and reliability than FETs using nano‐crystal ITZO. Furthermore, constant photocurrent method (CPM) measurement was carried out in order to estimate density of deep‐level defect states caused by oxygen vacancies in oxide semiconductors. The results show that CAAC‐ITZO has lower density of deep‐level defect states than nano‐crystal ITZO. We attribute the improvement in reliability of ITZO‐FETs to a decrease in deep‐level defect states of an ITZO active layer, as is the case with IGZO.  相似文献   
5.
The flux of the CaO‐Al203‐BaO‐CeO2‐MgO system as a desulphurization flux containing no fluorine for the secondary metallurgy process was evaluated in this study. The flux composition was designed using the eutectic compositions of the binary systems. The melting and desulphurization abilities of the fluxes were evaluated by measuring their liquidus temperatures and the distribution ratios of sulphur between the fluxes and the carbon‐saturated iron or stainless steel. The lowest liquidus temperature of 1325°C was obtained by adding 5.7 mass% MgO to the 80mass%A‐20mass%B flux. (A: 12CaO‐7Al2O3, B: BaCeO3+12mass%Al2O3). The distribution ratios of sulphur and sulphide capacities of the fluxes in this study were higher than those of the commercial product of calcium aluminate flux. This means that the CaO‐Al2O3‐BaO‐CeO2‐MgO fluxes developed in this study have higher desulphurization and melting abilities compared with the commercial product of calcium aluminate flux.  相似文献   
6.
Poly[vinylidenefluoride‐co‐(tetrafluoroethylene)] (P(VDF‐TeFE)) exhibited clear spherulitic texture with negative birefringence. The number and growth rates of the spherulites decreased at high crystallization temperature than at low crystallization temperature. Nonetheless, overall larger spherulites were found at high crystallization temperature and the brightness of the spherulites increased very fast at low crystallization temperature, thereafter it seemed as diminution of birefringence. AFM was used to investigate the impact of organo modified nanodiamond(ND) on spherulitic textures, lamellar thickness, and thickness distribution of P(VDF‐TeFE) copolymer. Poly[ethylene‐co‐(tetrafluoroethylene)] (ETFE) also confirmed spherulites structure and the boundaries could be clearly observed. By incorporation of the organo modified nanodiamond (ND) and organo‐modified montmorillonite (MMT) in fluropolymer matrix, it was found that spherulitic texture was seriously disordered and their nanohybrids was found only to have poorly developed spherulite structure. Both of the nanohybrids samples show better crystallization temperature as compared to their neat copolymer samples. Furthermore, the incorporation of nanoparticles decreased the size of the spherulites. POLYM. ENG. SCI., 57:161–171, 2017. © 2016 Society of Plastics Engineers  相似文献   
7.
Polymer-based nanohybrid materials were created using sustainable sepiolite clay composed from ubiquitous elements. Although sepiolite is generally recognized as a fibrous natural clay mineral, it turned out to be an acicular microcrystal because of the organo-modification of the outermost surface. Surface modification was performed using phosphonic acid derivatives containing hydrocarbon chains or fluorocarbon chains. Formation of a bidentate bond enhanced the desorption temperature and made nanocomposite preparation possible by melt compounding with polymers having a high melting point. As a result of organo-modification, amphiphilic sepiolite was obtained, and nanodispersion in an organic solvent was achieved. This technology was useful for detailed evaluation of sepiolite morphology. The nanocomposite of crystalline polymers/organo-modified sepiolites achieved uniform dispersion of these nanofillers in the matrix polymer. The introduction of 1 wt% nanofillers did not impair the transparency of the matrix polymer. As a result, a lamellae structure of the polymer developed, the crystallinity increased, and the mechanical properties improved. In addition, the crystallization temperature was improved, indicating that organo-modified sepiolites may act as a nucleating agent. It was found that sepiolite nanofiller with a highly aggregated tendency can achieve a well-nanodispersed state, even in phase-separable fluoropolymers, by applying fluorocarbon modification. POLYM. ENG. SCI., 60:541–552, 2020. © 2019 Society of Plastics Engineers  相似文献   
8.
The transitional behaviors of myoblasts toward differentiation were investigated in the cultures at the low and high seeding densities (respectively, X0 = 1.0 × 103 and 2.0 × 105 cells/cm2). In the culture at the low seeding density, an increase in confluence degree accompanied a decrease in growth potential (Rp), being Rp = 0.85 and 0.11 at t = 48 and 672 h, respectively. Myoblasts seeded at the high density resulted in the immediate cessation of growth with keeping the low range of Rp = 0.02–0.09 throughout the culture. The reduction of Rp led to the generation of three subpopulations of cells in proliferative, quiescent and differentiated states. Close cell contacts in the confluent state of high seeding culture induced cell quiescence to a higher extent with suppressing differentiation.  相似文献   
9.
Residual stresses induced by three scribing methods, diamond point scriber, laser scriber and diamond blade saw, are studied quantitatively by infra-red photoelasticity. It is clear that diamond blade saw scribing is most desirable, for residual stress induced by it is several times smaller than the stress caused by the other methods. The stress gradient differs between the laser scribed sample and the others, probably because of the difference in stress generation mechanism. Removing the damaged layer by etching reduces residual stress. The three scribing methods are also studied by the observation of defects after annealing and the results are compared with those determined by photoelastic measurement.  相似文献   
10.
A linear program was developed to help seismically active communities decide: (1) how much to spend on pre-earthquake mitigation that aims to reduce future losses versus waiting until after an event and paying for reconstruction, and (2) which of the many possible mitigation activities to fund so as to minimize overall risk. The mitigation alternatives considered are structural upgrading policies for groups of buildings. Benefits of mitigation are losses avoided in future earthquakes, including structural, non-structural, contents, and time-related losses, and casualties. The model is intended to be used as a tool to support the public regional mitigation planning process. In realistic applications, the model includes millions of variables, thus requiring a special solution method. This paper focuses on two efficient solution algorithms to solve the model—a Dantzig–Wolfe decomposition algorithm and a greedy heuristic algorithm. A comprehensive numerical study compares the two algorithms in terms of solution quality and solution time. The study shows that, compared to the Dantzig–Wolfe algorithm, the heuristic algorithm is much faster as expected, and provides comparable solution quality.  相似文献   
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