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Fifty years ago Juhn A. Wada developed the intracarotid amobarbital procedure (IAP), a test in which first one and then the other cerebral hemisphere is temporarily anaesthetised through direct intracarotid application of sodium amytal. The IAP was devised initially as a method to allow unilateral electroconvulsive shock therapy for psychosis. The method subsequently proved its value for the lateralisation of language and, following adaption of the test protocol, for the assessment of memory functions. Thus the IAP became the standard test in the presurgical evaluation for resective surgical treatment of medically intractable epilepsy. This paper will briefly review the history of the IAP, the controversies concerning its current applications and its expected eventual replacement by less invasive and more easily repeatable methods, notably functional magnetic resonance imaging.  相似文献   
363.
In the first half of this century a computing problem became evident in the course of preparatory research for major hydraulic projects in the Netherlands. One of the most novel problems was to predict the changes in the tidal movements caused by hydraulic works in coastal waters. Between 1920 and 1960 several solutions were proposed and put into practice: numerical methods, contracting young men for the calculations, analogue electronical networks and large scale models. The amount of computing labour played a decisive part in the choice between these methods. After a storm surge in 1953 causing estensive inundations in the southern part of The Netherlands, the requirements of the Delta Works project gave an enormous impetus to all three types of methods.  相似文献   
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ABSTRACT. Incorporating regional asymmetry and negative feedbacks (congestion) in a model of economic geography and international trade shows that complete specialization of production at one location is unlikely. We identify an agglomerating force: the home market effect, and two spreading forces, competition for demand from immobile sectors of production and congestion. We demonstrate that negative feedbacks can explain the economic viability of small industrial regions observed in the real world. Simulations clarify the basic structure of the model.  相似文献   
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Spatial Moving Behavior of Two-Earner Households   总被引:1,自引:0,他引:1  
Economic theory suggests that job choice, residential choice and commuting behavior are simultaneously determined. The case of two-earner households deserves special attention because the two wage earners share a dwelling but have different workplaces. We base our analysis of spatial moving behavior on search theory. We demonstrate that job mobility depends positively on the distance between the workplaces of the two wage earners. Residential mobility seems to be negatively influenced by the distance between the workplaces of the two wage earners. The search model also indicates that two-earner households will, on average, move less often than single wage earners.  相似文献   
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The study of location and colocation of economic activities lies at the heart of economic geography and related disciplines, but the indices used to quantify these patterns are often defined ad hoc and lack a clear statistical foundation. We propose a statistical framework to quantify location and colocation associations of economic activities using information-theoretic measures. We relate the resulting measures to existing measures of revealed comparative advantage, localization, specialization, and coagglomeration and show how different measures derive from the same general framework. To support the use of these measures in hypothesis testing and statistical inference, we develop a Bayesian estimation approach to provide measures of uncertainty and statistical significance of the estimated quantities. We illustrate this framework in an application to an analysis of location and colocation patterns of occupations in US cities.  相似文献   
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