Analysis of a parametrically driven pendulum.

We study in this paper the behavior of a periodically driven nonlinear mechanical system. Bifurcation diagrams are found which locate regions of quasiperiodic, periodic, and chaotic behavior within the parameter space of the system. We also conduct a symbolic analysis of the model which demonstrates that the symbolic dynamics of two-dimensional maps can be applied effectively to the study of ordinary differential equations in order to gain global knowledge about them.

Desipramine versus phenelzine in recurrent unipolar depression: clinical characteristics and treatment response.

We compared desipramine with phenelzine in a double-blind, parallel-groups study of 43 outpatients with recurrent unipolar depression. Response to the two drugs was similar, with an overall average reduction in scores on the Hamilton Rating Scale for Depression of about 50% over 6 weeks. Improvement was negatively correlated with initial severity of depression, especially in patients treated with desipramine. Response to desipramine was better in patients with moderate to severe stressors and no previous hospitalizations. Response to either treatment was better in patients whose course consisted of recurrent depressions with a stable baseline, even if the baseline was dysthymic.

Purification of human blood platelet monoamine oxidase.

Monoamine oxidase B has been purified from human blood platelets 185-fold to a specific activity of 113 nmole/min/mg protein by a combination of Triton X-100 solubilization and ion exchange chromatography. A protein fraction corresponding to 58,000 Da on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was identified as monoamine oxidase by its ability to bind [3H]Pargyline.

Colorimetric assay for monoamine oxidase in tissues using peroxidase and 2,2'-azinodi(3-ethylbenzthiazoline-6-sulfonic acid) as chromogen.

Monoamine oxidase is assayed in tissue by a colorimetric reaction using horse radish peroxidase and 2,2'-azinodi(ethylbenzthiazoline-6-sulfonic acid to measure H2O2 formed during oxidation of amines. The method has a coefficient of variation of approximately 2.5% and provides results comparable with those of radiometric assay. Monoamine oxidase activities in rat liver mitochondria and crude mitochondrial fraction from brain and with tyramine as a substrate were 18.9 +/- 0.4 and 4.61 +/- 0.15 nmol/min/mg of protein, respectively, using this method. Kinetic parameters of liver and brain monoamine oxidase with various substrates and inhibitors appeared to be the same when determined by either colorimetric or radiometric methods.

[Clinical contribution to so-called homilopathy]. / Klinischer Beitrag zur sogenannten Homilopathie.

Twenty cases are presented as a basis for reopening the discussion concerning the homilopathy concept introduced by Kraepelin. The authors describe three different degrees of expression of the homilopathic syndrome. The investigations suggest that homilopathic impediments are much more common than the usage of the term indicates. Possibilities of therapy and prophylaxis are discussed.