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High temperature thin film strain gauges are widely used in the strain measurement of extreme conditions, especially in the high temperature components. ITO thin film strain gauges can generally be applied to the strain measurements above 1000℃. ITO high temperature thin film strain gauge was fabricated on the ceramic substrate using magnetron sputtering, and then was thermal treated at high temperature in pure N2 atmosphere, with the purpose of studying its microstructure, XPS, temperature resistance characteristics and piezoresistive response. The results show that the temperature coefficient of resistance (TCR) of ITO thin film strain gauge can stabilize at -750×10-6℃-1. In addition, ITO thin film strain gauge is loaded at 1200℃, and the results show that the drift rate is 0.0018 h-1 and the strain factor is 16. Stable TCR and low drift rate of ITO thin film strain gauge provide the possibility for its application in the strain measurement of the hot end components.

Abstract: Gold catalysts supported on high surface area CeO2 were synthesized and tested for low temperature formaldehyde oxidation. It was found that the reactivity was greatly enhanced by increasing surface area of the support. Complete conversion of formaldehyde was obtained on a 3.0Au/CeO2-270 catalyst with a surface area of 270m2 g−1 at 50°C, and a conversion of 92.3% was obtained at 37°C over the same catalyst, which made it promising for indoor formaldehyde removal. Detailed characterizations of the catalyst showed that the enhancement could be attributed to two factors. One was that Au species mainly in high oxidation states formed on the high surface area CeO2 resulted in a high degree of HCHO adsorption, as revealed by in situ diffuse reflectance infrared Fourier transform spectroscopy. The other was the high surface area CeO2 provided more oxygen vacancies by the nano effect and the formation of Au x Ce1−x O2−δ solid solution as revealed by Raman spectroscopy, on which oxygen molecules could be transformed to active species for the reaction. [Copyright &y& Elsevier]

Aim: To investigate the effects and underlying mechanisms of resveratrol and genistein on contractile responses of rat gastrointestinal smooth muscle., Methods: Isolated strips of gastrointestinal smooth muscle from Spraque-Dawley rats were suspended in organ baths containing Kreb's solution, and the contractility of smooth muscles was measured before and after incubation with resveratrol and genistein, and the related mechanisms were studied by co-incubation with various inhibitors., Results: Resveratrol and genistein dose-dependently decreased the resting tension, and also reduced the mean contractile amplitude of gastrointestinal smooth muscle. Estrogen receptor blockades (ICI 182780 and tamoxifen) failed to alter the inhibitory effects induced by resveratrol and genistein. However, their effects were attenuated by inhibitions of α-adrenergic receptor (phentolamine), nitric oxide synthase (levorotatory-NG-nitroarginine), ATP-sensitive potassium channels (glibenclamide), and cyclic adenosine monophosphate (SQ22536). In high K(+)/Ca(2+)-free Kreb's solution containing 0.01 mmol/L egtazic acid, resveratrol and genistein reduced the contractile responses of CaCl2, and shifted its cumulative concentration-response curves rightward., Conclusion: Resveratrol and genistein relax gastrointestinal smooth muscle via α-adrenergic receptors, nitric oxide and cyclic adenosine monophosphate pathways, ATP-sensitive potassium channels, and inhibition of L-type Ca(2+) channels.

In the bimetallic cyanide-bridged title complex, [Fe(0.98)HoRu(0.02)(CN)(6)(C(3)H(7)NO)(4)(H(2)O)(3)]·H(2)O, the Ho(III) ion is in a slightly distorted square-anti-prismatic arrangement formed by seven O atoms from four dimethyl-formamide (DMF) mol-ecules and three water mol-ecules, and one N atom from a bridging cyanide group connected with the Fe(III) atom which is octa-hedrally coordinated by six cyanide groups. In the crystal, mol-ecules are held together through O-H⋯N and O-H⋯O hydrogen-bonding inter-actions to form a three-dimensional framework. Elemental analysis of one of the precursors and the crystal shows that there is a slight contamination of Fe by Ru. The Fe site displays, therefore, small substitutional disorder with site-occupancy factors Fe/Ru = 0.98:0.02. The two methyl groups of two dimethyl-formamide ligands are positionally disordered with site-occupancy factors of 0.44 (3):0.56 (3) and 0.44 (3):0.56 (3).

Background: Hydrogen sulfide (H(2)S) plays an important role in the smooth muscle cell relaxation and thereby participates in the development of hypertension. Cystathionine gamma-lyase is the key enzyme in the endogenous production of H(2)S. Up to now, the reports on the relationship between the polymorphisms of cystathionine gamma-lyase gene (CTH) and essential hypertension (EH) are limited. This study was designed to assess their underlying relationship., Methods: A total of 503 hypertensive patients and 490 age-, gender- and area-matched normotensive controls were enrolled in this study. Based on the FASTSNP, a web server to identify putative functional single nucleotide polymorphisms (SNPs) of genes, we selected two SNPs, rs482843 and rs1021737, in the CTH gene for genotyping. Genotyping was performed by the polymerase chain reaction and restriction fragment length polymorphism method (PCR-RFLP). The frequencies of the alleles and genotypes between cases and controls were compared by the chi-square test. The program Haplo. stats was used to investigate the relationship between the haplotypes and EH., Results: These two SNPs were in Hardy-Weinberg Equilibrium in both cases and controls. The genotype distribution and allele frequencies of them did not significantly differ between cases and controls (all P > 0.05). In the stepwise logistic regression analysis we failed to observe their association with hypertension. In addition, none of the four estimated haplotypes or diplotypes significantly increased or decreased the risk of hypertension before or after adjustment for several known risk factors., Conclusions: The present study suggests that the SNPs rs482843 and rs1021737 of the CTH gene were not associated with essential hypertension in the Northern Chinese Han population. However, replications in other populations and further functional studies are still necessary to clarify the role of the CTH gene in the pathogenesis of EH.

The present study was designed to investigate the acute relaxing effect of phytoestrogen resveratrol on isolated porcine coronary arteries and to determine the mechanisms underlying its vasodilatation. Rings of porcine coronary arteries were suspended in organ baths containing Krebs-Henseleit solution, and then isometric tension was measured. Resveratrol concentration-dependently relaxed arterial rings precontracted with 30 mM KCl. The IC(50) value of resveratrol was 38.67+/-3.21 microM. Incubation with N(omega)-L-nitro-arginine (L-NNA), endothelium removal or the presence of a potent inhibitor of protein tyrosine phosphatase sodium orthovanadate partly decreased the relaxation induced by resveratrol. However, the relaxation induced by resveratrol was unaffected by the estrogen receptor antagonist tamoxifen, the inhibitor of prostanoid synthesis indomethacin, the antagonist of beta-adrenoceptors propranolol or the protein synthesis inhibitor, cycloheximide. In addition, resveratrol significantly decreased the contractile responses of 5-HT, KCl and CaCl(2), and shifted their cumulative concentration-response curves to the right. These results suggest that the mechanisms of vasorelaxation induced by resveratrol are heterogeneous, two mechanisms participating partially in the relaxation of porcine coronary artery were detected in the study, one being the nitric oxide released from the endothelium, the other causing inhibition of Ca(2+) influx, but estrogen receptors were not involved in resveratrol-induced relaxation.

Aim: To determine the mechanisms of effects of phytoestrogen genistein on the contracted rabbit aortic arteries in vitro, and observe the effect of genistein and 17-beta estradiol on mean arterial pressure (MAP) in ovariectomized (OVX) rats., Methods: (1) Strips of rabbit aortic smooth muscle were suspended in organ baths containing Kreb's solution, and then isometric tension was measured. (2) Female mature Wistar rats underwent a bilateral ovariectomy (OVX). Sham-operated rats (SHAM) were used as controls. After administration of genistein (0.4 mg.kg(-1).d(-1), s.c.), 17-beta-estradiol (1 mg.kg(-1).d(-1), s.c.) or their vehicle sesame oil for 21 d, MAP was measured., Results: (1) Similar to 17-beta-estradiol, genistein could dose-dependently relax 40 mmol/L KCl-precontracted arterial strips. Incubation with N omega-L-nitro-arginine (L-NNA), methylene blue (MB), indomethacin, propranolol or endothelium removal did not affect relaxation induced by genistein. In calcium-free solution containing 0.01 mmol/L egtazic acid (EGTA), genistein inhibited not only the first phase contraction induced by noradrenaline (NA), but also the second contraction induced by CaCl2. In addition, genistein could reduce the contractile responses of NA, KCl and CaCl2, and shift their cumulative concentration-response curves rightward. (2) MAP in OVX rats was significantly higher compared with that of SHAM rats. However, after chronically treatment with genistein or 17-beta estradiol for 21 d the baseline MAP in OVX rats was reduced significantly., Conclusions: (1) The vasodilator effect of genistein in vitro is endothelium independent and not related to the nitric oxide, its mechanisms being probably due to inhibition of Ca2+ influx through calcium channels in a noncompetitive manner and Ca2+ release from intracellular store induced by NA. (2) Administration of genistein or 17-beta estradiol can chronically decrease MAP in OVX rats.

Aim: To investigate the effect of beta-estradiol on trachea smooth muscle contraction in vitro and in vivo., Methods: (1) Rabbit tracheas were incubated in organ baths filled with Krebs solution and supplied with a mixed gas of 95 % O2 and 5 % CO2. The isometric force was measured by ink-writing recorders. (2) The incubation period of asthma induced by histamine and acetylcholine (ACh) in guinea pig were measured before and after beta-estradiol (1 mg/kg) were given intramuscularly., Results: (1) Administration of beta-estradiol (0.1 mmol/L) caused relaxation of isolated trachea muscle strips (TMS) in rabbits pre-contracted by ACh and KCl (39 % +/- 5 % and 45 % +/- 19 %). The presence of indomethacin or methylene blue partly decreased the relaxation to beta-estradiol (26 % +/- 8 % and 28 % +/- 13 %), but Nomega-nitro-L-arginine (L-NNA) and propranolol and epithelium removal did not affect it (38 % +/- 10 %, 40 % +/- 15 %, 37 % +/- 8 %). beta-Estradiol can shifted the concentration-response curves of ACh and CaCl2 to the rightward (pD2 = 3.98 and 4.75). In addition, it could also significantly inhibit the contraction of phase caused by ACh, but did not affect the contraction of phase II caused by CaCl2. (2) The incubation period of asthma in guinea pig were delayed by beta-estradiol (1 mg/kg) given intramuscularly., Conclusion: (1) The relaxation of beta-estradiol in vitro was epithelium independent and associated with the inhibition of potential-dependent channel and release of Ca2+ from sarcoplasm reticulum induced by ACh. In addition, release of prostaglandins from trachea smooth muscle cells and relaxation through cGMP approach were also included. beta-Adrenoceptor-mediated relaxation was not involved. (2) beta-Estradiol can relax the trachea in vivo in guniea pig.