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关键词： 船舶定线制和报告制   船舶航行环境   层次分析法   模糊综合评判  

摘要： 船舶定线制和报告制在我国的实施已经有几十年的历史,为了确定船舶定线制和报告制的实施对船舶航行环境的实际影响效果,本文结合相关调查问卷的情况,利用层次分析法确定各船舶定线制和报告制评价指标的权重,进而利用模糊综合评判的方法对船舶定线制和报告制对船舶航行环境的影响进行评价。为进一步在船舶定线制和报告制区域内加强海上交通安全监管,提高船舶航行效率提供可行性参考。

关键词： ETSI   电磁干扰   信息化   电力线   无线通信  

摘要： 电力线高速数据通信技术是一个正在发展中的崭新学科。电力线一般用来传输220V／50Hz电能，为了提供从数Mbit／S到数十Mbit／S以上的数据传输，就必须采用数MHz以上的频段。但在当前的技术条件下，这会引发严重的EMl（电磁干扰）。例如，***公司的PLC系统运行后，发现路灯变成了发射天线，干扰了包括英国广播公司4台在内的多家广播电台的无线电信号接收。本文将就PLC系统的电磁兼容特性进行分析，并对于其频谱管理提出一些建议。

关键词： 介质损耗   定子线棒   高压接线   电极  

摘要： 介绍了在定子线棒的介质损耗测量过程中高压接线和电极对测试结果的影响,通过理论分析计算和实际测量结果对比,提出了3种降低发电机定子线棒介质损耗测量误差的方法。

关键词： 重大科技基础设施   高海拔宇宙线观测站   院地合作   成果转化  

摘要： 高海拔宇宙线观测站(Large High Altitude Air Shower Observatory,LHAASO)项目是中国科学家在国际宇宙线研究领域提出的重大前沿项目,也是中国在西南地区布局的又一重大科技基础设施。LHAASO项目的实施将最终建成具有国际先进水平的宇宙线研究中心,与世界其他3个宇宙线观测站(位于阿根廷的极高能宇宙线观测站、位于南极的中微子天文观测站、待建的甚高能伽玛天文观测站)形成优势互补,对宇宙线起源这一世纪之谜发起冲击,并推动粒子物理学、天文学、宇宙学领域的相关科学研究产生突破性进展。同时,项目的建设运行也将对设施所在地的科学研究、学科发展、人才培养有重要影响,提高地区科学普及水平,并带动相关经济文化发展。文章将针对重大科技基础设施对地方的科技教育及经济社会影响进行初步分析。

关键词： Crystallite size  

摘要： Nanocrystalline tin oxide (SnO2) powders with different grain size were prepared by chemical precipitation method. The reaction was carried out by varying the period of hydrolysis and the as-prepared samples were annealed at different temperatures. The samples were characterized using X-ray powder diffractometer and transmission electron microscopy. The microstrain and crystallite size were calculated for all the samples by using Williamson-Hall (W-H) models namely, isotropic strain model (ISM), anisotropic strain model (ASM) and uniform deformation energy density model (UDEDM). The morphology and particle size were determined using TEM micrographs. The directional dependant young's modulus was modified as an equation relating elastic compliances (s(ij)) and Miller indices of the lattice plane (hkl) for tetragonal crystal system and also the equation for elastic compliance in terms of stiffness constants was derived. The changes in crystallite size and microstrain due to lattice defects were observed while varying the hydrolysis time and the annealing temperature. The dependence of crystallite size on lattice strain was studied. The results were correlated with the available studies on electrical properties using impedance spectroscopy. (C) 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.

关键词： Bioactive amines   Polyamines   Sorghum bicolor L.   Extraction   Hydric stress  

摘要： The profile and levels of bioactive amines in different sorghum lines were reported for the first time. The amines were quantified by ion-pair HPLC, post-column derivatisation with o-phthalaidehyde and fluorimetric detection. The extraction procedure was optimised: 420 gm particle size, extraction with 5% trichloroacetic acid and three extractions. The screening of 22 sorghum lines showed that four of the ten amines investigated were detected. Spermine and spermidine were the prevalent amines (100%), followed by putrescine (77%) and cadaverine (14%). Total amines ranged from 5.8 to 41.4 mg/100 g, and the polyamines represented 60-100% of the total. Sorghum without tannin had higher amines levels compared to sorghum with tannin and cadaverine was specific to samples without tannin. Hydric stress caused accumulation of spermidine in the grains and affected the levels of other amines at rates depending on the presence or not of tannin. Sorghum is a significant source of polyamines. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Research Article  

摘要： Vitamin D plays a role in cancer development and acts through the vitamin D receptor (VDR). It regulates the action of hormone responsive genes and is involved in cell cycle regulation, differentiation and apoptosis. VDR is a critical component of the vitamin D pathway and different common single nucleotide polymorphisms have been identified. Cdx2 VDR polymorphism can play an important role in breast cancer, modulating the activity of VDR. The objective of this study is to assess the relationship between the Cdx2 VDR polymorphism and the activities of VDR in human breast cancer cell lines and carcinomas breast patients. Cdx2 VDR polymorphism and antiproliferative effects of vitamin D treatment were investigated in a panel of estrogen receptor-positive (MCF7 and T-47D) and estrogen receptor-negative (MDA-MB-231, SUM 159PT, SK-BR-3, BT549, MDA-MB-468, HCC1143, BT20 and HCC1954) human breast cancer cell lines. Furthermore, the potential relationship among Cdx2 VDR polymorphism and a number of biomarkers used in clinical management of breast cancer was assessed in an ad hoc set of breast cancer cases. Vitamin D treatment efficacy was found to be strongly dependent on the Cdx2 VDR status in ER-negative breast cancer cell lines tested. In our series of breast cancer cases, the results indicated that patients with variant homozygote AA were associated with bio-pathological characteristics typical of more aggressive tumours, such as ER negative, HER2 positive and G3. Our results may suggest a potential effect of Cdx2 VDR polymorphism on the efficacy of vitamin D treatment in aggressive breast cancer cells (estrogen receptor negative). These results suggest that Cdx2 polymorphism may be a potential biomarker for vitamin D treatment in breast cancer, independently of the VDR receptor expression.

关键词： 地下结构   抗震设计   反应位移法   计算参数   灵敏度分析  

摘要： 针对反应位移法计算参数多样性的特点,在设定一个基本工况的基础上,分别对反应位移法中的弹簧系数、地层位移、地层剪力、惯性力4种计算参数以及2种常用的计算模型进行了灵敏度分析,归纳了各个参数的取值方法及误差来源,并对比分析了2种计算模型的计算结果。结果表明,地层剪应力的取值对结构内力的计算结果影响最大,其次为地层变形,弹簧系数的影响最小;在计算模型的选取上,采用结构顶部加弹簧的模型计算的结构内力整体上要比顶部不加弹簧的模型计算的结构内力大,忽略上部土体约束作用,后者的计算结果偏于危险。

关键词： 技术力量   高等教育   地平线   教育技术   学习技术   教育信息化   美国高校   教育领域  

摘要： 新媒体联盟（NMC）与美国高校教育信息化协会（ELI）最新发布的2015年高等教育版《地平线报告》认为，自带设备（BYOD）和翻转课堂将是在1年内被采用的教育技术，未来2年至3年被高等教育采用的技术是“创客空间”和“可穿戴技术”，而自适应学习技术和物联网将会在未来4年至5年被教育领域广泛采用《地平线报告》将教育技术定义为“可用于提高教学、学习和创新研究的工具与资源”。

关键词： 腰椎曲度   卧位   站立位   X线摄影  

摘要： 目的:比较站立位与卧位X线摄影对腰椎曲度评价的影响。方法:对50例患者分别行站立位与侧卧位X线腰椎检查,采用Seze法测量不同体位的腰椎曲线指数和前凸指数,Cobb法测量不同体位的腰椎前凸角(Cobb角),Ferguson法测量不同体位的骶骨倾斜角,对测量数据进行统计学分析。结果:50例患者站立位与侧卧位的弓顶水平均主要位于第三腰椎中份水平。腰椎曲线指数站立位为(1.033±0.323)cm,侧卧位为(0.701±0.348)cm,两者之间有统计学差异(P=0.000),两者之间具有显著相关性(r=0.764,P=0.000)。前凸指数站立位为(1.126±1.185)cm,侧卧位为(0.572±1.138)cm,两者之间有统计学差异(P=0.011),两者之间具有显著相关性(r=0.694,P=0.000)。腰椎前凸角(Cobb角)的数值站立位为(44.380±9.930)°,侧卧位为(33.240±9.490)°,两者之间有统计学差异(P=0.000),两者之间具有相关性(r=0.419,P=0.002)。骶骨倾斜角的数值站立位为(31.820±7.410)°,侧卧位为(24.940±6.840)°,两者之间有统计学差异(P=0.000),两者之间具有相关性(r=0.357,P=0.011)。结论:两种X线摄影体位下所测得的腰椎曲度参数值有统计学差异,但具有相关性。两种摄影体位所获得的参数值不能相互替代。