Angiotensin II stimulates cardiac myocyte hypertrophy via paracrine release of TGF-beta 1 and endothelin-1 from fibroblasts

We examined the effects of different cytokine combinations and culture conditions on the expansion and modulation of cell surface antigens of CD34+ derived dendritic cells (DCs), the most efficient antigen-presenting cells capable of stimulating resting T cells in the primary immune response. Cells with a dendritic morphology and expressing HLA-DR, CD1a, S100 and CD83 were maximally expanded under serum-free conditions with the addition of SCF, GM-CSF, TNF-alpha, TGF-beta and Flt-3 ligand (fold increase of CD1a+ cells = 102 +/- 32 after 2 weeks of culture). CD34+ cells were also grown under continuous flow conditions in an artificial capillary system: after 14d of culture, the expansion in the total cell number was lower than that of the static cultures (3.3 +/- 2 v 18.9 +/- 4) but the percentage of CD1a+/CD83+/ CD80+ cells was considerably higher, whereas the CD14+ cells were significantly reduced (8.9 +/- 2 v 26 +/- 13). In continuous perfusion cultures, low levels of DC precursors and of LTC-IC were still present up to day 14. The DCs generated under flow conditions stimulated the mixed leucocyte reaction (MLR) more than the cells grown in static cultures. By electron microscopy, cells grown in the continuous flow system showed an increased number of large cells with numerous dendritic processes and abundant multilamellar complexes. The cells expanded under these conditions were sorted on the basis of their light-scatter properties into two fractions: one containing a predominance of CD1a+/S100+/ CD8 3+/CD80+/CD14- 'large cells' with great internal complexity (mature DCs); the second including 'small cells' either CD33+/CD14+, CD33+/CD15+ or CD33+/CD13-/CD14. The DCs generated and selected with this method are therefore particularly well suited for immunotherapeutic protocols.     

Effect of routine screening for Down's syndrome on the significance of isolated fetal hydronephrosis

OBJECTIVE: To determine the risk of Down's syndrome in fetuses with isolated hydronephrosis at 18-23 weeks in an unselected general population after routine screening for Down's syndrome, using first trimester nuchal translucency measurement and second trimester maternal serum biochemistry. POPULATION: All pregnant women undergoing a routine 18-23 week ultrasound scan, from a population who had been offered screening for Down's syndrome. SETTING: A district general hospital serving a low risk obstetric population. METHODS: Prospective study of all routine 18-23 weeks ultrasound scans. The prevalence of isolated hydronephrosis and Down's syndrome was determined and the relative risk for Down's syndrome was calculated for different ultrasound findings. RESULTS: 10,971 women were scanned at 18-23 weeks during the study period. Down's syndrome was diagnosed in 14 of 20 cases before this stage using first trimester nuchal translucency measurement and second trimester maternal serum biochemistry. Isolated fetal hydronephrosis was diagnosed in 423 pregnancies (3.9%); none of these pregnancies were affected by Down's syndrome. The relative risk for Down's syndrome was 0.18 (95% CI 0.06-0.53) for women with a normal scan (n = 9983). When multiple ultrasound markers were found (n = 565), the relative risk for Down's syndrome was 2.00 (95% CI 0.18-22.10) and 9.00 (95% CI 1.14-71.30) for all other aneuploidies. CONCLUSION: The finding of isolated fetal hydronephrosis does not significantly increase the age-related risk for Down's syndrome. The presence of multiple ultrasound markers is associated with an increased risk of aneuploidies other than Down's syndiome. These findings are explained by the reduced prevalence of Down's syndrome as a result of prior screening and diagnosis of this condition.     

中国古代治水理念及对城市水系统建设的经验启示

我国历史上水患频繁,劳动人民经过长期的探索,在处理水与聚居地关系方面的经验经过历代总结和传承,形成了比较系统完整的治水理念.在区域尺度重视水资源的综合利用,在城市尺度强调空间的科学布局,在院落尺度推崇天人合一的建设理念.结合我国现代城市水系统问题,对中国古代治水优秀的实践经验进行总结凝练.从系统和理念层面,对我国城市水系统规划建设总结出若干经验和启示.     

基于不确定性的雄安新区城市水系统安全保障技术研究

为提升雄安新区应对气候变化和急性冲击灾害的适应能力,建设高韧性高弹性的城市水系统,实现新区水系统的安全运行与可持续发展,构建了基于不确定性的雄安新区城市水系统安全保障技术.该技术包括水系统的风险源识别、风险综合评价和风险管理策略3部分.在应对气候变化方面,提出了"气候变化模拟预估—气候变化增量分析—水系统影响风险分析"的技术框架、不同精度的气候变化增量分析方法,以及分层级的城市水系统气候变化影响与风险分析方法.在应对急性冲击方面,提出了有效识别城市水系统面临的急性冲击风险源识别方法,以及急性冲击灾害多情景多灾种风险分析方法.在安全保障机制方面,提出了建立雄安新区水系统应急预案体系的要求,以及区域协同、综合应对、专业负责和网格化管理的"城市-组团-社区"三级风险管控机制.     

基于开源平台的数字图书馆的设计与实现

本文分析数字图书馆的功能需求,对开源平台下的系统进行框架和结构设计,并详细介绍在线服务和客户端程序两部分的实现,提出了构建于快速响应体系架构下实现快速存储,使用Django和第三方搜索引擎实现快速检索,采用高效的LinuxReiser文件系统组织管理数字资源以及应用CRM实现个性化推荐服务。     

基于多代理的微电网需求响应机制研究

为了解决微电网电能产消和就近高效消纳的问题,提出了一种多代理微电网交易模型,实现微电网多层面运营主体的利益共赢及资源统筹.在此基础之上,考虑到微电网中负荷不确定性的问题,设计了需求响应机制并引入奖惩制度,既激励用户积极参与响应又避免用户逐利行为,指导用户合理用电.算例分析表明,本文所提机制能有效提高微电网的经济效益和环境友好程度,显著降低用电成本,为分布式光伏参与电力市场交易提供支撑.     

浅析"一带一路"装备制造人才培养

"一带一路"倡议对全球经济的影响日渐凸显,国内各行各业实现飞速发展最关键的是强化人才竞争,人才力量不断发展能从根本上提高企业整体竞争力,让企业在全球市场竞争中立于不败之地.本文从"一带一路"背景入手,分析目前装备制造人才培养模式,剖析其中存在的不足,进一步总结我国"一带一路"装备制造人才培养的要点和方法.     

一种新颖的低层视觉特征到高层语义的映射方法*

通过在低层视觉特征上提取图像的局部颜色和纹理特征,再利用模糊神经网络建立低层视觉特征和高层语义特征之间的映射,实现了图像属性信息的有效传递和可靠检索.最后,为了提高检索效率,把相关反馈引进到图像检索系统中.实验证明,该方法取得了较好的检索查全率和准确率.     

一个面向电子政务的信息交换与共享平台的设计与实现*

基于J2EE、XML等技术,设计并实现了一个面向电子政务的信息交换与共享平台.对平台的总体结构、元数据定义与管理、数据交换模式等关键问题进行了论述,最后给出了平台的模块实现.该平台已经应用于北京市信息资源管理中心,实现了遥感信息、区县图层、企业基础信息等资源的交换与共享.