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关键词： Y-27632   beta(2)-adrenoceptors   cAMP   Bronchial epithelial cells   Equine asthma  

摘要： The present study addresses the effect of the Rho-kinase (ROCK) inhibitor Y-27632 on the beta(2)-adrenoceptor density and beta-agonist-stimulated intracellular second messenger cAMP formation in primary equine bronchial epithelial cells (EBEC). Y-27632 significantly decreased the beta(2)-adrenoceptor number (B-max) without markedly affecting the receptor affinity (dissociation constant, K-D) to the radioligand [I-125]-iodocyanopindolol (ICYP). In contrast, Y-27632 augmented the beta-agonist-stimulated intracellular cAMP production. Herein, Y-27632 markedly increased the maximal cAMP responses (E-max) (isoproterenol > epinephrine > norepinephrine) but did not shift the beta-agonist concentration-effect curves to the left. The beta(2)-selective antagonist ICI 118.551 and the beta(1/)beta(2)-antagonsit propranolol but not the beta(1)-selctive antagonist CGP 20712A reversed the isoproterenol-induced cAMP formation equally in Y-27632-treated and control EBEC, suggesting the effect was merely related to the beta(2)-subtype. These results show that Y-27632 differentially regulates the receptor density and function. Thus, these findings provide the first evidence that the functional interaction of the beta(2)-adrenoceptor and Rho-kinase (ROCK) signaling pathways decreases the receptor expression but enhances receptor downstream cAMP formation. This differential regulation of the receptor density and function by Y-27632 should be further reconsidered with regard to the beneficial effect of the drug in asthma therapy.

关键词： Schiff base   Pincer ligand   Isonicotinylhydrazide   DFT   Antibacterial activity   Anticorrosion study  

摘要： A novel NNO pincer type ligand (E)-N'-(phenyl(pyridin-2-yl)methylene)isonicotinohydrazide, PPMINH, was synthesized by condensation of 2-benzoyl pyridine and isonicotinylhydrazide. The ligand PPMINH on reaction with metal ions Fe(III), Co(II) and Ni(II) yielded six metal derivatives. Different analysis tools like;Elemental analyses, ESI-MS, FT-IR, molar conductivity, UV-spectra, magnetic susceptibility, NMR and EPR measurement were used. Theoretical FT-IR, H-1 NMR and C-13 NMR of ligand and complex 6 exhibits quite a good correlation coefficient. EPR spectrum of complex 6 at LNT suggests octahedral geometry around Ni(II). The ligand and complexes were screened for antibacterial activity. DFT has been carried out to optimize the geometry of the ligand and complexes. The properties most relevant to their potential action as corrosion inhibitors has been calculated all parameters of DFT from the inhibitor molecule to the metal atom. The corrosion inhibition effect of compounds on mild steel in an acidic medium was studied for 24, 48, 72 h using weight loss measurement. (C) 2021 Elsevier B.V. All rights reserved.

关键词： 寒冷地区   民用建筑墙体   节能   保温   防火监理   验收  

摘要： 当前,北方寒冷地区建筑在节能设计条件下的消防使用受到限制,对不同形式的墙体保温工程的应用提出了很大的挑战。在夹芯隔热设计系统中,各种隔热技术方案层出不穷,工程应用中存在的问题也层出不穷。对于节能保温工程和消防工程的监督验收越来越重要,本文论述了在燃烧特性的监督验收中应注意的控制点并对节能工程验收中检验员的分工和合理的整改措施提出了建议。

关键词： 市政道路施工   伸缩缝施工技术   技术应用  

摘要： 本文的研究目的是为了明确伸缩缝施工技术在市政道路施工中的重要性,并分析了具体的应用。现阶段,在经济发展的要求下,我国交通道路的压力日益增多,问题逐渐突出。因此,为了解决这些问题,我国开展了相应的市政道路建设工程,并将伸缩缝施工技术应用其中。该技术可以降低材料对温度的敏感程度,调整性能差异,还能够减少车辆荷载对道路的破坏,因此,这项技术得到了广泛应用。但即便如此,该技术也存在一定的问题需要解决。

关键词： Nanoscale   Biomaterial   Molecular   Stress/strain relationship   Tissue  

摘要： In annulus fibrosus (AF), type I collagen (Col-I) dominates outer AF (OAF) while type II collagen (Col-II) dominates inner AF (IAF). Using molecular dynamics simulations, this work reports how molecular-level structural and mechanical differences between Col-I and Col-II contribute to AF exhibiting radially varying structure and mechanical properties. Results show that differences in interpolypeptide forces and residue solvent accessibility contributes to Col-I showing intact triple-helix, lower backbone kinks and interpolypeptide separation (IPS), and thus contributing to expression of lower intermolecular spacing in collagen fibrils, lower lamellae thickness and lower water content in OAF. Furthermore, Col-I primarily exhibits backbone stretch while Col-II exhibit backbone straightening under tension, despite having comparable elastic moduli of similar to 3.5 GPa and similar to 3.2 GPa during backbone stretch. Such differences contribute to OAF showing stiffer stress-strain characteristics under tension. Furthermore, higher slenderness ratio of Col-I leads to buckling under compression-contributing to larger radial bulge being exhibited by OAF lamellae.

关键词： 屋顶绿化   中小学   校园   构建模式  

摘要： 中小学作为城市的重要组成部分,其校园屋顶绿化对于发展绿色校园,提升校园整体生态环境,促进师生身心健康发展具有重要意义。本文分析当前国内中小学屋顶绿化的现状及问题,探索适合中小学校园的屋顶绿化构建模式,并对几种模式进行对比分析,以期为中小学校园屋顶绿化建设提供一定的参考价值。

关键词： 市政路桥   伸缩缝施工   重要性   应用  

摘要： 市政路桥施工属于重要的基础设施建设,与其他一般的城市道路工程建设不同,其中对于伸缩缝施工来说,施工质量会直接关系到路桥工程的外观结构、行车舒适性(交通安全)、耐久性以及整体上的安全稳定性,所以相关施工技术人员有必要对这方面的施工应用进行重点分析。伸缩缝在施工中的重要性是不容忽视的,在市政路桥工程中具体施工的过程中要把握伸缩缝的锚固筋与预埋件安装定位、切割与开槽、伸缩缝的安装和焊接、混凝土配合比的优化、混凝土拌和浇筑和养护等几个关键要点,还有就是关注其他一些注意事项,从而确保伸缩缝施工的效果,切实提高市政路桥的建设质量。本文主要围绕伸缩缝施工在市政路桥施工中的应用进行了分析,以供参考。

关键词： 公路桥梁   伸缩缝   技术剖析  

摘要： 近几年国内经济水平的快速增长,为建筑行业的发展提供了良好契机,现代公路桥梁工程无论是在数量或者是规模方面,都表现出了快速增长的趋势,但与此同时,有关公路,桥梁工程施工质量水平的要求也在同步发生变化。虽然近几年科学技术的快速发展,使得公路桥梁施工过程中所使用的各种新兴技术快速涌现,伸缩缝施工就属于其中的一种,但是这些新兴技术的应用在质量保障方面很在一定的不足,有必要展开相关技术的全面剖析,目的在于保障该项技术的正确应用,维护工程的整体质量水平,基于此,本文重点分析公路桥梁施工过程中所使用的伸缩缝施工技术,目的在于明确该项施工技术的应用要点和质量控制关键环节,用于支撑公路桥梁工程施工的顺利进行。

关键词： 伸缩缝施工   市政道路桥梁   道路桥梁施工  

摘要： 由于市政道路桥梁需要长期可靠运行,这就要求建设单位必须从长远发展的角度设计市政道路的施工方案,施工人员应按照方案要求,控制施工的各个环节,特别是各种施工技术的准确应用,从而减少外部因素的干扰,避免施工质量问题的发生。伸缩缝施工工艺受施工环境温度影响较大,伸缩缝施工也关系到市政道路的运营安全。因此,在实际伸缩缝施工中,要做好施工前的各项准备工作,准确应用切缝开槽技术,注意型钢变形的校核,做好后期伸缩缝的维护管理工作,从而提高伸缩缝的施工质量。