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Biomedical subjects

H P SCHWAN

Publications and source records attributed to H P SCHWAN.

At least 19 recordsLinked to original sources
PubMed1965

MICROELECTROPHORESIS WITH ALTERNATING ELECTRIC FIELDS.

The observation of a cloud-free vortex in the top of a violent convective storm over Oklahoma suggests a mechanism whereby large quantities of air may be brought directly from the lower stratosphere to the lower troposphere in the central part of such storms. That this mechanism, in combination with the torrential rains frequently generated by these systems, is capable of producing radioactive "hot spots" on the ground is pointed out. Climatological considerations and observations of accumulated strontium-90 in soils support the hypothesis that the Plains States are peculiarly subject to heavy contamination compared to other middle-latitude areas because of this mechanism.

Electrophoresis↗
PubMed1965

MICROELECTROPHORESIS WITH ALTERNATING ELECTRIC FIELDS.

Electrophoretic mobility of microscopically visible particles is measured from photographs of their oscillatory migration in a low frequency electric field. The measurements are inherently free of gravitational or thermal-convective drifting. Many measurements may be made from one photograph. An automatic timing circuit insures reproducibility and determines the sign of the particles' charge.

Electricity↗
PubMed1962

Electrical properties of the membranes of the pleuropneumonia-like organism A 5969.

The electrical properties of the pleuropneumonia-like organism A 5969 have been determined over the frequency range from 0.5 to 250 Mcps. The frequency dependence of the dielectric constant and conductivity of PPLO suspensions is completely consistent with the existence of a membrane. The PPLO has an internal conductance which in part reflects its ionic equilibrium with normal nutrient and macromolecular constituents. But it is fairly independent from variation in external ionic strength.

Membranes↗
PubMed1960

Electrical properties of mitochondrial membranes.

The electrical capacity of the membrane of rat liver mitochondria is 0.5 to 0.6 micro./cm(2). This membrane capacity is obtained from the analysis of the frequency dependence of the admittance of a suspension of swollen mitochondria. In potassium chloride media the mitochondrial membrane capacity does not depend on the ion concentration. The internal conductance of the mitochondria was approximately one-half that of the external medium; the same applies if the mitochondria are equilibrated in a medium with a 10-fold difference in potassium chloride concentration. Hence the swollen mitochondria investigated here appear to be able to adjust their internal ion concentration in proportion with that of the external phase. The similarity of the membrane capacity of isolated mitochondria with the range of values known for other membranes suggests a common molecular structure. The analysis of experimental data suggests an anisotropic electrical behavior of the interior of mitochondria. This anisotropy is readily explained by the existence of internal membranes.

Animals↗