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Biomedical subjects

W Weidlich

Publications and source records attributed to W Weidlich.

5 recordsLinked to original sources
PubMed1990

Settlement formation. Part I: a dynamic theory.

"The dynamic process of settlement formation is a fundamental issue in regional science. Our proposed model integrates the economic and migratory sectors in terms of endogenous variables in order to describe the evolution of continuous population distributions as a self-organising process.... The purpose...is to show that under strongly idealised conditions, a population consisting of different subpopulations with different economic activities will evolve into a differentiated population pattern. Each member of the subpopulations has the possibility to migrate between locations stimulated by rational economic reasons. This idea, which seems almost self-evident on the level of qualitative argumentation, [will] be cast into a mathematically self-contained quantitative dynamic model."

Behavior↗
PubMed1987

A dynamic phase transition model for spatial agglomeration processes.

A nonlinear model of population migration is presented in order to provide a dynamic explanation for the formation of metropolitan areas. "In Section 2 the model is introduced in terms of the rate equations for the mean values of the regional population numbers with specifically chosen individual transition rates. Section 3 gives a survey of concepts and results for the convenience of the reader not interested in the details of the mathematical derivations. Section 4 derives the stationary solutions of the rate equations, that is, the equilibria of the system. Section 5 treats the time dependent solutions of the model equations focussing on the exact analytic solutions along so-called symmetry paths. Section 6 analyzes the dynamic stability of the symmetry path solutions and decides which stationary states are unstable and which are stable equilibrium states."

Demography↗
PubMed1977

[Enzyme studies of synovial fluid from osteoarthritis knee joints (author's transl)].

In 40 patients who were operated on for meniscopathy, accompanied by more or less severe arthroses of the knee joints, the total activity of LDH-T and of the LDH-H isoenzyms could be evaluated. The data show that severe arthroses without any synovitic reactions as well as cases with inactive chronic synovitis showed small total activities of LDH, whereas cases with clinical and macroscopic-anatomically active synovitis (including the so-called activated arthroses) showed a great total activity of LDH. Furthermore the dominance of LDH-H isoenzyms has been found to indicate an aerobic situation of the metabolism.

Chronic Disease↗
PubMed1976

[Cytological examinations of synovial for judgement arthrotic conditions at knee joint (author's transl)].

Even if you use very refinded methods of investigation, there might be some difficulties in the estimation of praearthrotic and arthrotic conditions in the knee joint, especially under the aspect of differential diagnostical considerations. In those cases all the diagnostical measures available should be applied. In this paper the value and power of evidence of cytological investigations with arthrotic alterations of the knee joint are checked. For this purpose some synovial liquid was punctured in 25 cases--chosen out of a total number of 140--of operations (mostly on behalf of suspectes meniscopathy). The liquid was worked up in the method found by Vojtisek and analysed. It was possible to correlate the thus found results (analysis of the differential cell formation) with the findings which were objectively gained during the operation. Thereby you could see that the macroscopically visible changes of the synovialis, the menisci and the cartilage, which were divided into 5 groups regarding their form and their degree of significance, allowed a comparison with the findings of the differential cell formations. It is possible to attach certain forms of the differential cell formation to varying macroscopic-anatomic changes of the knee joint. The results are thoroughly discussed.

Cytodiagnosis↗