Skeletal distribution of degenerative changes in vertebral osteophytosis,vertebral osteoarthritis and DISH

In order to comprehend the condition of vertebral osteophytosis, vertebral osteoarthritis and DISH (diffuse idiopathic skeletal hyperostosis) with respect to diagnosis and aetiology, the vertebral and peripheral (appendicular) frequency and distribution pattern of degenerative joint changes of 176 rather affluent citizens were analysed from the late medieval city of Dordrecht in Holland. Patterns of frequencies with respect to age and sex were found to be similar essentially to those of a present-day Dutch suburban village population. Frequencies for vertebral osteophytosis were twice those for vertebral osteoarthritis, and both increased with age in both sexes. The individual pattern of vertebral osteophytosis and vertebral osteoarthritis seems to indicate that each disorder possesses its own progressive identity. From the distribution pattern and frequency of peripheral osteoarthritis it was concluded, with respect to the vulnerability of developing this complication under physically moderate life conditions, that causal factors for vertebral osteophytosis are less important than those for vertebral osteoarthritis. Osteoarthritis presented itself as a systemic disorder, affecting synovial joints in general. Finally it was appreciated that, with increasing age, bony outgrowths from joint degeneration become anatomically masked by para-articular ossifications from DISH.     

Estimating the Marginal Willingness to Pay for Commuting

With informational frictions on the labor market, hedonic wage regressions provide biased estimates of the willingness to pay for job attributes. We show that a recent theoretical result, which states that the variation in job durations provides a basis for obtaining good estimates, can be generalized to a wide class of search models. We apply this result by estimating the marginal willingness of employed workers to pay for commuting, using Dutch longitudinal data. The average willingness to pay for one hour commuting is estimated to equal almost half of the hourly wage rate.     

Juhn A. Wada and the sodium amytal test in the first (and last?) 50 years

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.     

Die Berechnung von Wasserfluten. Tideforschung in den Niederlanden, 1920–1960

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.     

NEGATIVE FEEDBACKS IN THE ECONOMY AND INDUSTRIAL LOCATION*

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.     

Spatial Moving Behavior of Two-Earner Households

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.