Treatment Evaluation—A Modelling Approach with Application to Acute Myeloid Leukaemia

The work described in the paper was developed during a project carried out jointly by the DHSS OR Unit and a hospital department specializing in the management of acute myeloid leukaemia. One of the aims of this project was to develop a methodology for comparing the results of treatment of patients treated in different clinical trials.The standard OR approach was adopted of using a mathematical model of the results of treatment in a trial as a basis for such comparisons. The paper describes how such a model was built for a particular treatment trial and then used to compare the results of this trial with those obtained in another trial. This comparison indicated important differences between the results of the treatment trials.     

Changes in Students' Science Ability Produced by Multimedia Learning Environments: Application of the Linear Logistic Model for Change

The purpose of this study was to measure changes in students' science proficiency produced by a multimedia learning environment, Astronomy Village: Investigating the Solar System, developed at Wheeling Jesuit University's Center for Educational Technologies with funding from the National Science Foundation. The inquiry‐based design of Astronomy Village supports middle school students in learning fundamental concepts in life, earth, and physical science. Astronomy Village was compared to an alternative treatment that simulated elements of traditional science instruction using web site access to background materials and content in Astronomy Village. The results indicate sizable treatment effects for two groups of Astronomy Village students, as well as for the alternative treatment group. Differences in the treatment effect sizes among the three treatment groups reveal the relative merits of different approaches to using technology. The Linear Logistic Model for Change applied in this study is beneficial for comparing alternative uses of technology, since it separates effects due to treatments from natural trend effects and eliminates drawbacks of traditional statistical designs for pretest‐posttest changes.     

Global dynamics of an epidemiological model with age-of-infection dependent treatment rate

We revisit a previously established model for influenza transmission dynamics, in which antiviral treatment as a single containment strategy was administered within a specified window of opportunity for initiating treatment. We extend this model to a more general framework with age-of-infection dependent treatment rates. The resulting age structured model can be transformed into a closed system of delay differential equations, for which we perform a complete global stability analysis. By constructing suitable Lyapunov functions, we show that the effective reproduction number fully characterizes the possible outcomes of disease dynamics. Our results allow us to evaluate treatment strategies and examine the impact of treatment delays on the potential success of disease control.     

通脑活络针刺法治疗脑梗死患者的BI与NIHSS指数的协方差分析

利用协方差分析将那些认为很难控制的因素,即患者入院时的BI得分或NIHSS得分作为协变量x,在排除协变量x对观测变量y,即治疗90天后患者的BI、NIHSS得分影响的条件下,分析治疗方法对治疗90天后患者的BI、NIHSS得分的影响,从而更加准确地对治疗方法进行评价.     

Modeling,simulation and adaptive process control of biotechnological processes in decentralized anaerobic treatment of domestic wastewater

Control in anaerobic wastewater treatment plants is difficult to achieve but necessary due to a high sensitivity to disturbances and process complexity. With the help of different mathematical tools, control strategies can be developed. Particularly, a well-defined mathematical model can be highly effective for design, assessment and optimization of treatment plants. However, applications directly in the control system of a treatment plant are hard to achieve due to model complexity and usually require specialized software and the engagement of experts in the subject. The objective of the present study was the development of less empirical methods for assessment and control of a decentralized anaerobic plant for the treatment of domestic wastewater. A lab-scale plant, which consisted of a two-stage anaerobic digestion process followed by an anaerobic ammonium oxidation (ANAMMOX) reactor for nitrogen removal, was used as object of study. Ordinary differential equation models were implemented to simulate the processes that took place in the treatment plant. With the help of the implemented models, control tools were developed. These tools include a standalone application for monitoring of the two-stage anaerobic digestion process and an ammonium estimator for the ANAMMOX reactor by means of artificial neural networks (ANNs). The procedures followed aimed to reduce the amount of experimental work required so they can be easily transferred from laboratory to full-scale conditions. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

基于χ~2检验法的通脑活络针刺法对脑梗死患者BI指数的影响

用r×s列连表的Pearson x~2检验法,讨论通脑活络针刺法、溶栓剂法与常规法在各救治时间窗对脑梗死患者BI评分的影响,并得到结论,通脑活络针刺法在各救治时间窗的"治愈率"及较好的康复程度方面显示了显著疗效.     

Efficacy analysis of a body-mass-reduction treatment using mathematical modelling

Obesity was categorized as a chronic disease by the World Health Organization (WHO) in 1997 because the problem had reached at pandemic level and presented a serious risk factor with respect to people who have been developing type-2 diabetes, hyperdyslipidaemia and hypertension. These four risk factors tend to accelerate the development of cardiovascular diseases. As a result, obesity has also become a significant social and economic burden. An important observation with regard to the population exhibiting increased body mass is the fact that they would like to decrease their weight, although they are frequently not successful. In this paper, a modelling-and-simulation approach is used for the presentation, analysis and explanation of the reasons that have an important influence on the treatment’s efficacy. The presented modelling results are based on the observation and treatment experiences of patients in a specialized institution over a period of 15 years, where each year around 100 new patients enter the treatment programme. The introduction of the motivation principle in the model structure allows strong support for the actions of the therapeutic team in a closed-loop manner, as the checking of different scenarios for the individual patient is easily realized. The efficacy of the treatment can, in this way, be significantly improved. In the past 6 years, which mainly involved open-loop treatments, the dropout rate was 70%. After the introduction of proposed closed-loop approach, this was reduced to 27% in the past year. As a consequence, the effect on body-mass control was significantly improved.     

An Interactive Simulation in the Health Service

There is an unmet demand for the treatment of irreversible kidney failure, particularly in the older age groups. A model of the treatment system was built to explore the implications of meeting the demand, giving different priorities to the available treatments and changing the balance between home and hospital. This discrete event simulation, developed in the Wessex Region, describes the system realistically, including resource use and constraints, the arrival of kidneys for transplantation and the matching of donors with recipients. It is written in Pascal on an Apple II computer and uses shadow entities to describe the survival of patients on each type of treatment. The model was validated with techniques which included the use of a tabular display while the simulation was running. The model has proved to be easy to use and robust both to different data requirements and extreme policy changes. The techniques developed have more general application in the Health Service context.     

Optimal investment in the reclamation of eutrophic water bodies

Eutrophication, i.e., the abnormal growth of phytoplankton, is considered in this note, which focuses on the optimal treatment of eutrophic water bodies. The issue is addressed by the use of a nonlinear model where phytoplankton and the number of wastewater treatment plants in operation are the state variables. The decision maker is a governmental agency which has to define the time pattern of investment in new plants so as to minimize the present value of environmental and treatment costs. The optimal solution is shown to have the following features. First, the optimal size for the wastewater treatment system is attained in minimum time. Subsequently, investment replaces wornout treatment plants, and phytoplankton adjusts asymptotically to its optimal equilibrium value.This work was supported by Centro Teoria dei Sistemi—CNR, Milano and by Fondazione ENI E. Mattei.     

Modelling energy-economic interactions in developing countries: A linear programming approach

This paper describes the energy-economic assessment model recently developed at Brookhaven National Laboratory for application to energy assessments in developing countries. This model was designed to be directly applicable to these countries, and as such particular emphasis was given to a simple, yet comprehensive treatment of the energy sector. The discussion stresses the treatment of the electric, refinery and industrial end use sectors, and the linkages with conventional macroeconomic planning models.