To advance the understanding of the corrosion behavior of stainless steel bellows in marine atmospheric environments and enhance the precision of service life predictions,this study employs finite element simulations ...To advance the understanding of the corrosion behavior of stainless steel bellows in marine atmospheric environments and enhance the precision of service life predictions,this study employs finite element simulations to investigate the pitting corrosion rates and pit morphologies of bellows peaks and troughs under varying electrolyte film thicknesses.The model incorporates localized electrochemical reactions,oxygen concentration,and homogeneous solution reactions.For improved computational accuracy,the fitted polarization curve data were directly applied as nonlinear boundary conditions on the electrode surface via interpolation functions.Simulation results reveal that the peak regions exhibit faster corrosion rates than the trough regions.With increasing electrolyte film thickness(from 10μm to 500μm),corrosion rates at both peaks and troughs decrease progressively,and after 120 hours of simulation,the maximum corrosion rate at the peaks declines from 0.720 mm/a to 0.130 mm/a,and at the troughs from 0.520 mm/a to 0.120 mm/a,with the disparity in corrosion rates diminishing over time.Furthermore,as corrosion progresses,pits propagate deeper into the substrate,exhibiting both vertical penetration and lateral expansion along the passive film interface,ultimately breaching the substrate.This research offers valuable insights into designing corrosion mitigation strategies for stainless steel bellows in marine environments.展开更多
目的调查妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy,ICP)的发病及分布情况,描述ICP的流行病学特征。方法选择安徽省安庆市立医院为研究现场,分析2014年1月至2015年3月到安庆市立医院初次就诊并住院分娩的所有孕妇的...目的调查妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy,ICP)的发病及分布情况,描述ICP的流行病学特征。方法选择安徽省安庆市立医院为研究现场,分析2014年1月至2015年3月到安庆市立医院初次就诊并住院分娩的所有孕妇的临床资料。根据纳入和排除标准组成队列,计算住院孕妇的ICP发病率;根据ICP的人群分布、空间分布、时间分布特征分别进行分组和比较,对结果进行统计学描述。结果最终共有4 081例孕妇纳入研究,ICP发病率为8.55%。其分布特征表现为:入院孕周在34~37周、文化程度在初中及以下、携带HBV的孕妇ICP发病率较高,分别为18.40%、11.35%和12.80%;居住地在安徽省池州市的孕妇ICP发病率较高,为14.83%。结论妊娠晚期、受教育程度较低、携带HBV的孕妇发病率高,需引起注意,加强监测,并进行进一步探索。展开更多
目的探讨妊娠合并隐匿性或显性乙型肝炎病毒(hepatitis B virus,HBV)感染对早产发生率的影响。方法采用前瞻性队列研究设计,以2012年6月1日至2013年3月15日间安庆市立医院所有住院分娩的孕妇为研究对象,纳入妊娠结局为单胎活产的孕妇,...目的探讨妊娠合并隐匿性或显性乙型肝炎病毒(hepatitis B virus,HBV)感染对早产发生率的影响。方法采用前瞻性队列研究设计,以2012年6月1日至2013年3月15日间安庆市立医院所有住院分娩的孕妇为研究对象,纳入妊娠结局为单胎活产的孕妇,收集其血清并进行HBV表面抗原和HBV S基因片段的检测,并通过医院电子病历系统收集孕妇人口学信息等资料,采用单因素和多因素统计方法分析妊娠合并隐匿性和显性HBV感染对早产发生率的影响。结果孕妇早产发生率为21.00%(189/900);其中隐匿性HBV感染组、显性HBV感染组和非HBV感染组孕妇在人口学特征方面相似可比,其早产发生率分别为20.51%(16/78)、20.00%(14/70)、21.14%(159/752)。单因素与多因素分析未发现早产发生率与HBV感染相关,以非HBV感染组为参照,多因素COX回归分析发现显性HBV感染、隐匿性HBV感染与早产间调整后相对危险度(adjusted risk ratio,RRa)分别为1.03(0.81,1.32)和0.99(0.78,1.25);以同样参照,多因素线性回归分析发现孕周与HBV感染状况的回归系数β为0.09(-0.14,0.31)。结论妊娠合并隐匿性或显性HBV感染与早产的发生率无明显相关。展开更多
目的:探讨人胃腺癌阿霉素耐药细胞系SGC7901/ADR中多药耐药(multi drug resistance,MDR)产生机制,为胃癌多药耐药机制的研究提供新靶点。方法:采用MTT法测定3种常用化疗药物顺铂、表柔比星、5-氟尿嘧啶在人胃癌细胞系SGC7901及其阿霉素...目的:探讨人胃腺癌阿霉素耐药细胞系SGC7901/ADR中多药耐药(multi drug resistance,MDR)产生机制,为胃癌多药耐药机制的研究提供新靶点。方法:采用MTT法测定3种常用化疗药物顺铂、表柔比星、5-氟尿嘧啶在人胃癌细胞系SGC7901及其阿霉素耐药细胞系SGC7901/ADR中的作用;应用反转录聚合酶链反应(RT-PCR)技术检测SGC7901和SGC7901/ADR中mdr1、c-Jun的mRNA表达情况;转录因子AP-1分别转染入SGC7901和SGC7901/ADR中,应用双荧光素报告基因检测系统(Dual-Luciferase reporter assay system)检测其活性;Western Blot法检测P-gp、c-Jun在蛋白水平的表达。结果:SGC7901与SGC7901/ADR在化疗药物顺铂、表柔比星、5-氟尿嘧啶的不同浓度下作用72小时后,发现SGC7901/ADR中细胞的生存率无明显改变,而SGC7901的生存率却有显著的下降趋势;在mRNA水平对mdr1基因进行检测,SGC7901/ADR中的多药耐药基因的表达显著高于SGC7901,而P-gp在蛋白水平的检测中显示SGC7901/ADR相对与SGC7901,表达活性有明显升高;转录因子AP-1的表达分别在SGC7901及SGC7901/ADR中检测到,但SGC7901/ADR中AP-1的活性明显高于SGC7901;AP-1的主要组成成份c-Jun在SGC7901和SGC7901/ADR做mRNA及蛋白水平的检测,结果显示在SGC7901中未发现c-Jun的明显表达,而SGC7901/ADR中c-Jun的表达活性均显著升高。结论:在人胃腺癌阿霉素耐药细胞系SGC7901/ADR中有MDR的产生,同时伴多药耐药基因上调;转录因子AP-1的活性表达与胃癌细胞的多药耐药性密切相关,AP-1的表达高低可能是其形成机制之一。展开更多
基金supported by the National Natural Science Foundation of China(No.52074130)Engineering Research Center of Resource Utilization of Carbon-containing Waste with Carbon Neutrality,Ministry of Education,200237 Shanghai,PR China.
文摘To advance the understanding of the corrosion behavior of stainless steel bellows in marine atmospheric environments and enhance the precision of service life predictions,this study employs finite element simulations to investigate the pitting corrosion rates and pit morphologies of bellows peaks and troughs under varying electrolyte film thicknesses.The model incorporates localized electrochemical reactions,oxygen concentration,and homogeneous solution reactions.For improved computational accuracy,the fitted polarization curve data were directly applied as nonlinear boundary conditions on the electrode surface via interpolation functions.Simulation results reveal that the peak regions exhibit faster corrosion rates than the trough regions.With increasing electrolyte film thickness(from 10μm to 500μm),corrosion rates at both peaks and troughs decrease progressively,and after 120 hours of simulation,the maximum corrosion rate at the peaks declines from 0.720 mm/a to 0.130 mm/a,and at the troughs from 0.520 mm/a to 0.120 mm/a,with the disparity in corrosion rates diminishing over time.Furthermore,as corrosion progresses,pits propagate deeper into the substrate,exhibiting both vertical penetration and lateral expansion along the passive film interface,ultimately breaching the substrate.This research offers valuable insights into designing corrosion mitigation strategies for stainless steel bellows in marine environments.
文摘目的调查妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy,ICP)的发病及分布情况,描述ICP的流行病学特征。方法选择安徽省安庆市立医院为研究现场,分析2014年1月至2015年3月到安庆市立医院初次就诊并住院分娩的所有孕妇的临床资料。根据纳入和排除标准组成队列,计算住院孕妇的ICP发病率;根据ICP的人群分布、空间分布、时间分布特征分别进行分组和比较,对结果进行统计学描述。结果最终共有4 081例孕妇纳入研究,ICP发病率为8.55%。其分布特征表现为:入院孕周在34~37周、文化程度在初中及以下、携带HBV的孕妇ICP发病率较高,分别为18.40%、11.35%和12.80%;居住地在安徽省池州市的孕妇ICP发病率较高,为14.83%。结论妊娠晚期、受教育程度较低、携带HBV的孕妇发病率高,需引起注意,加强监测,并进行进一步探索。
