学生授课PK法在大学课堂教学中的运用

大学课堂大多以教师讲授为主,很难听到学生的观点与异议,学生的主动性与积极性难以激发,学习效果受到严重影响。本文提出一种提高大学课堂学习效果的学生授课PK法,这种方法将改变教师一贯唱主角的教学模式,同时提高学生参与学习的主动性、积极性。     

较量:文学经典中的另类母爱表达

爱怜少子是人们的普遍心态,因爱而较量则是一种另类母爱表达,是文学经典中的一道独特的风景线。爱是较量的动机,较量是一次爱心行动、一种爱心表达。爱心无可厚非,而爱心表达则因人而异,境界有别。孩子高于一切,不顾一切地保护孩子,是古往今来大多数母亲的共同心理。     

含氮有机碱结构参数与PK值的关系

对含甲基喹啉系列、含羟基唑啉系列衍生物及含甲基－硝基苯并咪唑系列衍生物分别作了计算，发现这些化合物的氮原子结构参数与相应的PK值有直线关系或抛物线关系。     

说"PK"

"PK"是随着<超级女声>的火爆而流行开来.本文考察了它的义项、语用意义、使用范围和场合,认为"PK"的义项有对决、淘汰、比较和对比、竞争4个义项.它的语用意义一般都与<超级女声>节目有关,常用于标题中和一些体育比赛场合.     

Modelling and simulation to improve decision‐making in clinical development

Modelling and simulation are buzz words in clinical drug development. But is clinical trial simulation (CTS) really a revolutionary technique? There is not much more to CTS than applying standard methods of modelling, statistics and decision theory. However, doing this in a systematic way can mean a significant improvement in pharmaceutical research. This paper describes in simple examples how modelling could be used in clinical development. Four steps are identified: gathering relevant information about a drug and the disease; building a mathematical model; predicting the results of potential future trials; and optimizing clinical trials and the entire clinical programme. We discuss these steps and give a number of examples of model components, demonstrating that relatively unsophisticated models may also prove useful. We stress that modelling and simulation are decision tools and point out the benefits of integrating them with decision analysis. Copyright © 2005 John Wiley & Sons, Ltd.     

A semi‐parametric approach to fitting a nonlinear mixed PK/PD model with an effect compartment using SAS

Modelling of the relationship between concentration (PK) and response (PD) plays an important role in drug development. The modelling becomes complicated when the drug concentration and response measurements are not taken simultaneously and/or hysteresis occurs between the response and the concentration. A model‐based approach fits a joint pharmacokinetic (PK) and concentration–response (PK/PD) model, including an effect compartment if necessary, to concentration and response data. However, this approach relies on the PK data being well described by a common PK model. We propose an algorithm for a semi‐parametric approach to fitting nonlinear mixed PK/PD models including an effect compartment using linear interpolation and extrapolation for concentration data. This approach is independent of the PK model, and the algorithm can easily be implemented using SAS PROC NLMIXED. Practical issues in programming and computing are also discussed. The properties of this approach are examined using simulations. This approach is used to analyse data from a study of the PK/PD relationship between insulin and glucose levels. Copyright © 2005 John Wiley & Sons, Ltd.     

游戏化竞争对在线学习用户行为的影响研究

为了吸引和激励用户,各种游戏设计元素被广泛应用于在线学习环境中.然而,这些游戏化设计对于用户行为的影响仍然有待系统性的理论解释,其实际作用也有待于深入的实证研究加以检验.本文基于“需求-可供性-功能特征”的视角,从自我决定理论和心理占有理论出发,分析游戏化竞争元素,包括间接竞争(如排行榜)和直接竞争(如一对一的对抗性竞赛,或称PK),对在线学习用户行为的影响.利用大规模客观数据,本文构建了一个面板数据集,通过倾向得分匹配加双重差分的计量估计,结果表明,游戏化间接竞争和游戏化直接竞争对于用户的在线学习行为均有正面影响.本文的研究从竞争元素的角度,揭示了自愿参与的在线学习场景中游戏化设计的作用机制,对于相关研究与实践具有多方面的参考意义.     

Optimal parametric design with applications to pharmacokinetic and pharmacodynamic trials

This paper considers optimal parametric designs, i.e. designs represented by probability measures determined by a set of parameters, for nonlinear models and illustrates their use in designs for pharmacokinetic (PK) and pharmacokinetic/pharmacodynamic (PK/PD) trials. For some practical problems, such as designs for modelling PK/PD relationship, this is often the only feasible type of design, as the design points follow a PK model and cannot be directly controlled. Even for ordinary design problems the parametric designs have some advantages over the traditional designs, which often have too few design points for model checking and may not be robust to model and parameter misspecifications. We first describe methods and algorithms to construct the parametric design for ordinary nonlinear design problems and show that the parametric designs are robust to parameter misspecification and have good power for model discrimination. Then we extend this design method to construct optimal repeated measurement designs for nonlinear mixed models. We also use this parametric design for modelling a PK/PD relationship and propose a simulation based algorithm. The application of parametric designs is illustrated with a three-parameter open one-compartment PK model for the ordinary design and repeated measurement design, and an Emax model for the phamacokinetic/pharmacodynamic trial design.     

流行语“PK”词源研究——评议《流行语“PK”解析》

近几年"PK"一词迅速走红,许多文章对其含义与语法功能作了详尽解析,而在讨论其起源时却显得过于随意。虽能找出源于电子游戏和源于足球点球两种观点,但在对二者进行比较时却未能作深入讨论,且理由略显单薄,缺乏说服力。本文力图从词义内涵、出现时间与使用频率三个方面入手,对比说明后者作为最初起源的优势,然后针对该问题又引入日语作为媒介语,大胆提出一种新的假设。