Film residual stress assessment method via temporarily thermal relaxation

The concept of temporarily thermal relaxation is extended theoretically to assess the film residual stress. First, the contribution of the initial stress to the observable displacement field is separated with eliminating the thermal expansion effect of the material. Then, the residual stress is inversely derived through the displacement increment. Finally, finite element analysis was carried out to provide numerical description of the partial relieve of the residual stress

“一带一路”中人民币的国际影响力

人民币对\"一带一路\"沿线国家、参与国货币的影响呈上升趋势,且人民币已处于\"一带一路\"货币汇率网络中的核心位置牛津大学历史学家彼得·弗兰科潘(2017)的畅销书《丝绸之路:一部全新的世界史》指出,两千多年前的丝绸之路上\"丝绸是一种最值得信赖的货币\"。两千多年后的今天,人民币成为\"一带一路\"上的\"丝绸\"。正值第二届\"一带一路\

为什么人民币越来越重要呢?——基于网络分析方法的汇率证据

本研究运用网络分析的计量模型构造了G20经济体货币汇率间相互影响的动态网络,并从网络重要性这一新的角度构造了人民币国际影响力指数,指数衡量了人民币汇率带动其它货币汇率同向变动的能力.2005年汇改以来,人民币的国际影响力越来越大.这一方面得益于人民币的市场化改革和人民币汇率的相对稳定,另一方面也得益于中国不断增长的对外贸易、投资以及较高的利差.国家自然科学基金资助项目(71871195;71988101)教育部人文社会科学研究规划资助项目(8YJA790121)中央高校基本科研业务费专项资金资助项目(20720171002

Effects of Taohong Siwu Decoction on the expression of pathological angiogenesis correlation factors including VEGF,KDR and Flt-1 in hepatic fibrosis mice

目的:从整体水平研究复方桃红四物汤对四氯化碳所致肝纤维化模型小鼠肝组织血管内皮生长因子(VEGF)、含激酶插入区受体(KDR)及Flt-1蛋白与mRNA表达的影响。方法:昆明小鼠60只,随机分组为空白组,模型组,秋水仙碱组,桃红四物汤高、中、低(17.00、8.50、4.25g/kg)剂量组,采用左侧腹股沟处皮下注射四氯化碳花生油溶液建立小鼠肝纤维化模型,给药6周后,运用酶联免疫吸附测定(ELISA)法检测肝组织VEGF蛋白含量;蛋白印迹法(Western blot)测定小鼠肝脏KDR、Flt-1蛋白的表达;逆转录PCR(RT-PCR)法测定小鼠肝脏VEGF、KDR及Flt-1 mRNA表达。结果:桃红四物汤治疗后,桃红四物汤高、中剂量组肝组织VEGF蛋白表达量较模型组降低(P<0.05,P<0.01),中药高剂量组肝组织KDR与Flt-1蛋白表达较模型组显著降低(P<0.05);而桃红四物汤高、中剂量组肝组织VEGF、KDR与Flt-1 mRNA表达较模型组、秋水仙碱组明显减少(P<0.01),并且呈现一定的量效正相关。结论:桃红四物汤能够降低肝纤维化病理血管生成相关因子的表达,减缓病理性的微血管生成可能是其改善肝纤维化的机制之一。Objective:To investigate the effects of Taohong Siwu Decoction(THSWD) on protein and mRNA expression of vascular endothelial growth factor(VEGF),kinase insert domain containing receptor(KDR) and Flt-1 in hepatic fibrosis model mice caused by CCI_4.Methods:Sixty Kunming mice were randomly divided into blank,model,colchicine(control)and three THSWD(17.00,8.50,4.25g/kg) groups,with 10 mice in each group.Except the blank group,the other groups' mice were subcutaneously injected with carbon tetrachloride(CCI_4)-arachis oil solution in left inguen to establish hepatic fibrosis mouse model.After administration for six weeks,the content of VEGF protein in liver tissue was measured by enzyme-linked immunosorbent assay(ELISA),protein expressions of KDR and Flt-1 in liver tissue were detected by Western blotting,and mRNA expressions of VEGF,KDR and Flt-1 in liver tissue were measured by reverse transcription polymerase chain reaction(RT-PCR).Results:After treatment,the content of VEGF protein in THSWD(17.00,8.50g/kg) groups were lower than that in model group(P<0.05,P<0.01).The protein expressions of liver tissue KDR and Flt-1 in THSWD(17.00g/kg) group were less than that in model group(P<0.05).The mRNA expressions of liver tissue VEGF,KDR and Flt-1 were significantly lower than that in both model and colchicine groups(P<0.01),which showed a certain positive correlation between dose and effect.Conclusion:Taohong Siwu Decoction could decrease the expression of pathological angiogenesis correlation factors of hepatic fibrosis,thus helpful to induce the formation of pathological capillary vessels,which may be one of the possible mechanisms of ameliorating hepatic fibrosis.国家自然科学青年基金项目(No.81202659);; 福建省自然科学基金项目(No.2014J01373);; 厦门大学新聘教师科研启动基金项目(No.ZK1014);; 福建省大学生创新创业训练项目(No.DC2013174)~

Deformation and failure in pre-stressed structure under laser irradiation

很多材料/结构由于加工制造和服役承载往往会蕴含残余应力或预应力。这种包含预应力的材料/结构在进一步受到热载荷作用时，由于材料热软化效应和热膨胀效应，会形成复杂的后续变形和破坏行为。特别是当热载荷高度局部化时，如激光束加热等，这种变形和破坏的复杂性会进一步加剧。针对预应力结构的局部热载荷响应，本文研究了典型单层/多层预应力平板结构的激光辐照变形和破坏行为，主要内容包括： 1）推导了等轴预拉伸薄膜结构的激光辐照热弹性变形的理论解，讨论了由预应力重新分布而引起的变形重分布特征，并基于其反问题阐述了一种测试薄膜预应力的热松弛法。 2）基于有限单元法分析了预应力钛合金板在连续激光辐照下的热弹塑性变形，通过试验观察预拉伸钛合金板在连续激光作用下的弹塑性变形和烧蚀行为，并进行了显微观察，分析了预应力钛合金板在局部激光热作用时的变形和破坏形貌。 3）基于有限单元法研究了气动热环境中的含残余应力的热障涂层/镍基高温合金多层结构的激光辐照行为。试验观察分析了复杂热边界条件下的多层结构在激光辐照时的变形破坏行为，获得了其破坏形貌

Film residual stress assessment method via temporarily thermal relaxation

The concept of temporarily thermal relaxation is extended theoretically to assess the film residual stress. First, the contribution of the initial stress to the observable displacement field is separated with eliminating the thermal expansion effect of the material. Then, the residual stress is inversely derived through the displacement increment. Finally, finite element analysis was carried out to provide numerical description of the partial relieve of the residual stress.</div

预加载结构局部异常热负荷破坏问题

&lt;正&gt;针对高超声速飞行环境中的预加载结构在局部异常热负荷作用下的完整性问题,描述了同时考虑气动加热和局部异常热流双重热负荷作用时的平板温度场;建立了预加载平板结构的热-弹塑性力学模型,分析了预加载平板结构在

Depression of older adults: a literature review of challenges

Background: Depression is the leading cause of premature death and disability worldwide. The globally aging population with increasing burdens of chronic diseases is certain to face increasing problems. Elderly people in whom physical and mental co-morbidities are common represent a group that is highly susceptible to the harm of depression. Worse still, the reduced accessibility of elderly to healthcare implies that the public health burden of depression seen in the healthcare sector is only tip of the clinical iceberg. Objectives: This review aims to synthesize the current evidence of public health burden of geriatric depression, and the public health challenges in tackling this growing threat in the context of under-detection, social disparities and population ageing, and to summarize its current situation in Hong Kong and compare with other Methods: A literature search was conducted in databases PubMed, Medline and Cochrane (January 2002-June 2012) using the keywords “depression, depressive episode, epidemiology, prevalence, incidence, elderly”. A total of 1285full-text articles were obtained, out of which 52 articles were potentially relevant. Critical appraisal was performed on articles after a priori specified inclusion and exclusion criteria were applied. After removing the duplicates and examining the contents, 15 articles were adopted for review. Results: Depression brings along heavy disease burden which highly associated with mortality and morbidity. Late-life depression accounts for 17-37% in primary care settings, while around 3% in the community. The ongoing problems of under-detection, under-treatment and the progressive population ageing increase the challenges and complexity of matter. Gender difference is identified, while social support, social relationships and socioeconomic status were shown to be highly correlated with elderly depression in both the East and the West. Conclusions: Elderly depression is a global threat causing increasing public health burden to healthcare systems and societies worldwide. Over the decades, public health sector is facing numerous challenges intackling it, including the practice-related challenges complicated by characteristics of elderly, policy-related challenges explained by the clinical iceberg concept, and societal related challenges. By understanding the older population and challenges in the community control of depression, it is the time to action and turn public health over a new leaf.published_or_final_versionPublic HealthMasterMaster of Public Healt