Temperature regulation in the Balkan spadefoot ( Karaman, 1928) at the beginning of nocturnal activity.

On land, the amphibians interact with the environment in a complex way-even small changes in the physiological conditions may significantly impact the behaviour and . In ectothermic tetrapods, the transition from inactive to active phase may be related to important changes in their thermal status. We studied the thermal ecology of adult Balkan spadefoots ( Karaman, 1928) in northeastern Bulgaria.

On the mechanism of stomatocyte-echinocyte transformations of red blood cells: experiment and theoretical model.

This study represents an attempt to achieve a better understanding of the stomatocyte-echinocyte transition in the shape of red blood cells. We determined experimentally the index of cell shape at various ionic strengths and osmolarities for native and trypsin-treated human erythrocytes. For every given composition of the outer phase, we calculated the ionic strength in the cells and the transmembrane electric potential using a known theoretical model.

Magnesium content in seminal fluid as an indicator of chronic prostatitis.

Magnesium and zinc are both involved in a high number of enzymic activities vital for mammals. They are found in prostate in remarkably high concentrations and released into seminal fluid. Furthermore, drastic reduction of Zn and Mg concentrations in the semen fluid may lead to disorders in male fertility.

Effect of Magnesium Ions on the Properties of Foam Films Stabilized with Sodium Dodecyl Sulfate.

Unstable and equilibrium foam films and foams formed from solutions of sodium dodecyl sulfate and bivalent electrolyte, MgCl2 or MgSO4, are experimentally investigated. It was found that at low ionic strength and low surfactant concentration the films with magnesium ions are more stable than films with sodium ions. At higher surfactant concentration the films containing MgCl2 become stable while the films with MgSO4 remain unstable.