Cyclamate intake and cyclohexylamine excretion are not related to male fertility in humans

Cyclamate and its metabolite cyclohexylamine affect male fertility in high dose animal studies, but this affect has not been investigated in epidemiological studies. This paper reports the first epidemiological study designed to investigate the possibility of a relationship between cyclamate and cyclohexylamine and male fertility in humans, in which 405 cases of clinically defined infertility in men and 379 controls were surveyed. Semen evaluation, urine analysis for cyclamate and cyclohexylamine and dietary questionnaires were compared between cases and controls. No evidence was found of a significant association between cyclamate intake and male infertility; neither high cyclamate nor high cyclohexylamine excretion were associated with elevated risk. The lack of association remained after adjusting by age, area of residence, education, total energy intake and other variables. No significant correlations were observed between cyclamate intake, metabolism or excretion, and sperm count and motility. The results demonstrate no effect of cyclamate or cyclohexylamine on male fertility at the present levels of cyclamate consumption.     

高炉冷却壁失效原因研究

本文针对安钢高炉冷却壁破损的形式、原因进行研究分析,探讨了冷却壁的结构、材质、加工与安装工艺对其寿命的影响。介绍了安钢高炉炉役后期冷却壁的维护生产实践。     

Describing metal surfaces and nanostructures with orbital-free density functional theory

Orbital-free density functional theory (OF-DFT) can be made to scale linearly with sample size, allowing thousands of atoms to be treated explicitly with quantum mechanics. State-of-the-art kinetic energy density functionals and ion–electron pseudopotentials are used to obtain accurate structural property predictions for nanoparticles, nanowires, extended surfaces, and nanoindentation of simple metals.     

Analytic methods for modeling longitudinal data from rolling therapy groups with membership turnover.

Interventions for a variety of emotional and behavioral problems are commonly delivered in the context of treatment groups, with many using rolling admission to sustain membership (i.e., admission, dropout, and discharge from group are perpetual and ongoing). The authors present an overview of the analytic challenges inherent in rolling group data and outline commonly used (but flawed) analytic and design approaches to addressing (or sidestepping) these issues. Moreover, the authors propose use of latent class pattern mixture models (LCPMMs) as a statistically and conceptually defensible approach for modeling treatment data from rolling groups. The LCPMM approach is illustrated with rolling group data from a group-based alcoholism pilot treatment trial (N = 128). Different inferences were made with regard to treatment efficacy under LCPMM vs. the commonly used standard group-clustered latent growth model (LGM); coupled with other preliminary findings in this area, inferences from LGMs may be overly liberal when applied to data from rolling groups. Continued work on data analytic difficulties in groups with membership turnover is critical for furthering the ecological validity of research on behavioral treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Space-time block codes which can be identified as rings

In this paper, we give a general criterion to determine when a complex space-time block code has a ring structure and then we provide a complete list of complex space-time block codes which have ring structures up to size 4.     

基于协作优化的塔机金属结构一体化设计

将多学科设计优化中的协作优化算法应用于塔式起重机金属结构的整体优化设计，针对协作优化算法系统级优化问题存在的计算困难，将其转化为无约束问题处理。通过对塔机金属结构的吊臂、塔帽、平衡臂的一体化优化设计，验证了方法的有效性。     

加氢反应器内构件—急冷箱的试验研究

急冷箱是加氢反应器的重要内件。洛阳石化工程公司设备研究所在认真分析UOP急冷箱的基础上,对其结构进行了改进,开发出了新型急冷箱(已获专利)。经过流体力学、传质、传热性能对比试验、分析,新型急冷箱结构性能优良。     

埕东油田埕913断块沙三段砂砾岩油藏储层特征研究

以井点分析为基础，利用棱磁共振测井等资料，对埕东油田埕913断块沙三段储层岩石进行分类；应用岩石铸体薄片、扫描电镜、压汞、CT等资料，以砂砾岩储层孔隙结构特征为重点，对其储层特征进行了研究。通过CT分析，确定了储层孔隙度，为落实储量规模提供了依据。     

Empirical Evaluations of Usage-Based Reading and Fault Content Estimation for Software Inspections

This thesis describes six empirical investigations of two techniques applied to software inspections, namely reading techniques and fault content estimation techniques. The first part of the thesis presents a series of experiments of a novel reading technique called usage-based reading. The second part investigates fault content estimation applied to the software inspection process. The estimation methods used are capture-recapture and curve fitting.     

炼油化工装置技术改造的决策与实施

针对炼油和石化工业装置技术改造的特点，系统地总结了技术改造的类型和改造方案的制定、决策及实施的原则、程序和方法，指出对炼化装置实施技术改造是一项极其复杂、极具难度的系统工程，必须结合实际情况，以投资回报最大化为原则，通过深入细致地研究和反复比选优化改造方案，并结合现场情况制定切实、可靠、安全的实施方案。