通过RTL8019AS实现多台单片机设备与PC机的通讯

通过以太网控制芯片RTL8019AS实现单片机与以太网的连接,采用AT89S52单片机作为通信系统的控制器,与多台单片机连接扩展,从而实现多台单片机通过以太网与PC机通讯.     

对十七大报告中关于效率和公平关系的思考

社会主义和谐社会的和谐点应该是效率与公平的均衡点。中国革命和建设的历程，就是不断追求效率与公平均衡统一的历史，不能忘记历史经验的警示：重视公平时压抑了效率，追求效率时又忽视公平；改革开放以来，我国在效率快速提高，GDP和人均收入普遍增加时，公平正义却遇到了空前的挑战，不公平的负效应是严重的，应引起我们的高度重视!当前在继续强调发展，提高效率的同时，必须更加突出公平，倍加关注社会弱势群体；通过深化改革，从制度、体制、政策等方面，切实保障弱势群体的合法权益。     

以科学发展观指导弱势群体权益保护的立法工作

弱势群体目前是一个受到社会各界广泛关注的概念,宁波市对维护弱势群体权益的工作十分重视。文章从科学发展观的角度,阐述了宁波市为维护弱势群体权益所取得的立法成果,指出了维护弱势群体权益立法工作中存在着的主要矛盾与问题,并提出了解决问题的方法。     

"禁讨区"的合理性思考

随着城市的流浪乞讨者越来越多,不少城市的政府部门拟设立"禁讨区"去治理这一棘手的问题,进而引发了一场针锋相对的大争论;赞同者认为,设立"禁讨区"限制乞讨也是一种文明,反对者则主张,设立"禁讨区"限制乞讨是对乞丐的歧视。笔者认为流浪乞讨现象的增加,是一个经济、政治、社会和历史的综合性问题,而绝不是一两个"禁讨区"就能解决的;设立"禁讨区"非良策,它不能使文明乞讨者的权利得到保障,并且有悖公平理念,"禁讨区"的无限扩大,将恶化乞讨者的生存环境,严重损害乞讨者的利益。     

河南高校体育弱势群体学生参与课外体育活动现状调查

通过文献资料法、调查法和数理统计法,对河南高校体育弱势群体学生参与课外体育活动的现状进行了调查分析,结果发现:体育弱势群体学生体质健康状况欠佳,他们有强身健体、丰富课余生活、抗病防病的体育活动动机,主要是参与一些休闲、强度易于控制的体育运动项目,但他们参与课外体育活动的频度很低。心理压力大、过于关注自身不利条件、缺乏运动兴趣以及没有适宜的运动项目和场地设施等因素,对他们参与课外体育活动有很大的阻碍作用。学校对体育工作的重视,体育教师的组织指导以及同学参与体育运动的积极性,都能够有效促进体育弱势群体学生参与课外体育活动。     

水铁矿促进湿地植物净化含砷微污染水源水的试验研究

为了研究水铁矿促进湿地植物净化微污染水体中砷的效果及机理,选用美人蕉,添加不同比例水铁矿的石英砂构建微型垂直流人工湿地,考察含砷微污染水连续漫灌条件下美人蕉根表铁膜中铁含量及砷在湿地基质和植物茎叶中的分布规律。结果表明:湿地基质中水铁矿的添加剂量在200 mg/kg以内,湿地基质吸附截留砷的能力随水铁矿添加剂量的增加而提高;超过200 mg/kg以后,增加水铁矿对湿地基质截留砷的能力影响不明显。美人蕉根表铁膜中的铁含量随湿地基质中水铁矿添加剂量(在50~1 200 mg/kg范围内)的增加而增加;渍水状态下的美人蕉净化含砷的微污染水,根表铁膜中铁含量在100 mg/kg左右,最有利于砷的吸收和最终去除。     

New approach for measurement of non-SHBG-bound testosterone in human plasma

Testosterone (T) circulates in the blood tightly bound to sex hormone-binding globulin (SHBG) and weakly to albumin. Measuring protein unbound T (free) or non-SHBG-bound T rather than total T has been recommended for the evaluation of androgen disorders in humans. Ammonium sulfate precipitation has been widely used to separate [SHBG-T] complex from free and albumin-bound T. To achieve more specificity in this separation, we used monoclonal anti-SHBG antibody and developed a suitable and convenient immunoassay for measuring non-SHBG-bound T. Magnetic beads were covalently coupled to a monoclonal anti-SHBG antibody to capture [SHBG-T] complex from plasma samples. Magnetic separation was then performed to allow measurement of non-SHBG-bound T in the supernatant by direct radioimmunoassay. When 300 μL of plasma samples were incubated at room temperature with 10 μL of anti-SHBG beads, residual SHBG concentration was undetectable in the supernatant. The specificity of proteins retained on anti-SHBG beads was further demonstrated by peptide mass fingerprint on a MALDI-TOF analyzer. The non-specific adsorption of T on beads was low (5%), and dissociation of T from SHBG-T complex was less than 5% after 180 min of incubation. The plasma concentrations of non-SHBG-bound T using anti-SHBG beads were highly correlated to those obtained using ammonium sulfate precipitation. We conclude that SHBG immunocapture is a highly specific and useful tool for an experimental direct measurement of plasma non-SHBG-bound T. This methodology is also convenient and appropriate for routine and automated assay.     

厚热塑性复合材料AS4/PEEK角铺设层合板的层间应力分析

将表征热塑性复合材料AS4 /PEEK非线性行为和应变速率相关行为的三维弹塑性模型通过程序加以实现。将程序计算结果和文献实验结果相比较可以发现,二者吻合较好,验证了所生成程序的有效性。计算了厚的AS4 /PEEK角铺设层合板[±25]s4在不同界面上的层间应力。由层间应力的三维分布图,分析了不同界面上层间应力的分布特征,并说明了可能引起层间分层的主要因素。     

Bulk derivatization and cation exchange restricted access media-based trap-and-elute liquid chromatography–mass spectrometry method for determination of trace estrogens in serum

Estrone (E1), estradiols (α/β-E2), and estriol (E3) are four major metabolically active estrogens exerting strong biological activities at very low circulating concentrations. This paper reports a sensitive and efficient method with automated, on-line clean-up and detection to determine trace estrogens in a small volume of serum samples using liquid chromatography–electrospray ionization–tandem mass spectrometry directly, without off-line liquid–liquid or solid-phase extraction pretreatments. Serum aliquots (charcoal stripped fetal bovine serum, 100 μL) were spiked with four estrogen standards and their corresponding isotope-labeled internal standards, then bulk derivatized with 2-fluoro-1-methyl-pyridium p-toluenesulfonate (2-FMP) to establish the calibration curves and perform method validation. Calibration was established in the concentration ranges of 5–1000 pg mL⁻¹, and demonstrated good linearity of R² from 0.9944 to 0.9997 for the four derivatized estrogens. The lower detection limits obtained were 3–7 pg mL⁻¹. Good accuracy and precision in the range of 86–112% and 2.3–11.9%, respectively, were observed for the quality control (QC) samples at low, medium, and high concentration levels. The stability tests showed that the derivatized serum samples were stable 8 h after derivatization at room temperature and at least to 48 h if stored at −20 °C. The method was applied to measure trace estrogens in real human and bovine serum samples, and three of four estrogen compounds studied were observed and quantified.