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Positron emission tomography is a noninvasive research technique used in medicine to measure the three-dimensional distribution of the biologically active substances, marked with a positron emitter in the living body. Positron emission tomography provides information about function of the tissue and not solely about its morphology, and is thus complementary to computer tomography and magnetic resonance imaging. Its basic principle … Preberite več >>

Physical principles of the description of fluid flow through a system of pipes and so­me mechanical properties of the blood circula­tion are put forward. As an example, the velocity field of the model vertebro-basilar junction is pre­sented. The influence of some geometrical parameters on the blood flow and on the deve­lopment of atherosclerotic changes is shown, proving thereby the importance … Preberite več >>

Electroporation is a process, which causes transient high-permeability of the cell membrane due to application of electric field. In the state of high-permeability, membrane allows different kinds of small and large molecules to be introduced into the cytoplasm, although the cell plasma membrane represents a formidable bar­rier for them in its normal state. Electroporation is governed by many parameters. Parameters … Preberite več >>

Electroporation is a phenomenon during which exposure of a cell to an electric field results in a significant increase in its membrane permeability. Reversible electroporation is widely used for internalisation of various substances in research, and is also becoming important in clinics (tumor electrochemotherapy). Electroporation is explained as formation of nanometer-sized aqueous pores in the lipid bilayer due to increased … Preberite več >>

High-voltage, nanosecond electric pulses (of a few to a hundred nanoseconds duration and electric field strength of a few ten kV/cm) are generated by a Blumlein generator. Such pulses induce sufficiently high voltage across intracellular membranes to cause pore formation in them. The effects of these pulses on cell organelles exceed those on the plasma membrane. High-voltage nanosecond pulses affect … Preberite več >>

A thermal foot manikin was developed for the determination of thermal insulation insulation (I,m² ·K/W) of footwear. The thermal foot manikin calculates the thermal insulation of 10 individual segments of the foot. Each copper segment of the manikin contains an electric heater and a temperature sensor. Insulation at each segment is determined by accounting for the difference in temperature … Preberite več >>