Acoustic-mechanical effect on the sperm of sturgeon fish using piezoactuators

To improve the quality of the frozen material during cryopreservation, scientists apply various effects on cells: mechanical, chemical or physical. In this work we use acoustic-mechanical effects on cells before cryopreservation. As a result of the studies, the optimal parameters of the impact of the piezoactuator were selected to improve the quality of defrosted reproductive cells of male sturgeons. The object of research was the sperm of the Russian sturgeon. The progressive motility time of native spermatozoa posure time (0.5 min; 1 min, 1.5 min) and frequency (300 Hz, 500 Hz, 550 Hz) were used. Analysis of the motility of thawed sperm showed that the best result in terms of the percentage of sperm motility was obtained when using a frequency of 500 Hz for 1 minute (27%). At the same time, the best indicator of sperm motility time was given by using a frequency of 300 Hz for 1 minute (390 s)

Application of piezoactuators in the technology of low-temperature preservation of fish reproductive cells

The sperm of Russian sturgeon (Acipenser gueldenstaedtii Brandt et Ratzeburg, 1833) was the research object. Acoustic-mechanical influence on sturgeon semen improves fish-biological and reproductive indices of the seminal fluid. The most optimal indices for reproductive cells of male Russian sturgeon are 500 Hz, 90 V with the exposure duration of 1 minute. It has been shown that when a piezo-actuator with a frequency of 500 Hz and an amplitude of 90 V is applied to the sperm mixture with the cryoprotectant, ice crystals are formed later, which may influence the survival of cells after defrosting

Understanding hysteresis in carbon dioxide sorption in porous metal-organic frameworks

Two new isostructural microporous coordination frameworks [Mn3(Hpdc)2­(pdc)2] (1) and [Mg3(Hpdc)2­(pdc)2] (2) (pdc2– = pyridine-2,4-dicarboxylate) showing primitive cubic (pcu) topology have been prepared and characterized. The pore aperture of the channels is too narrow for the efficient adsorption of N2; however, both compounds demonstrate substantially higher uptake of CO2 (119.9 mL·g–1 for 1 and 102.5 mL·g–1 for 2 at 195 K, 1 bar). Despite of their structural similarities, 2 shows a typical reversible type I isotherm for adsorption/desorption of CO2, while 1 features a two-step adsorption process with a very broad hysteresis between the adsorption and desorption curves. This behavior can be explained by a combination of density functional theory calculations, sorption, and X-ray diffraction analysis and gives insights into the further development of new sorbents showing adsorption/desorption hysteresis

Acoustic-mechanical effect on the sperm of sturgeon fish using piezoactuators

To improve the quality of the frozen material during cryopreservation, scientists apply various effects on cells: mechanical, chemical or physical. In this work we use acoustic-mechanical effects on cells before cryopreservation. As a result of the studies, the optimal parameters of the impact of the piezoactuator were selected to improve the quality of defrosted reproductive cells of male sturgeons. The object of research was the sperm of the Russian sturgeon. The progressive motility time of native spermatozoa posure time (0.5 min; 1 min, 1.5 min) and frequency (300 Hz, 500 Hz, 550 Hz) were used. Analysis of the motility of thawed sperm showed that the best result in terms of the percentage of sperm motility was obtained when using a frequency of 500 Hz for 1 minute (27%). At the same time, the best indicator of sperm motility time was given by using a frequency of 300 Hz for 1 minute (390 s)

Investigation of ice particle formation points during fish sperm cryopreservation

This study was conducted in order to investigate of the points of formation of ice particles during cooling of fish sperm. The object of the study was spermatozoa of the Russian sturgeon (Acipenser gueldenstaedtii Brandt, 1833), hybrid Acipenser ruthenus × Huso huso, the spiny-tailed sturgeon Acipenser nudiventris Lovetsky, 1828, and the inconnu Stenodus leucichthys Güldenstädt, 1772. The growth of ice microparticles is formed at the perturbation temperature of the corresponding aqueous suspension, with the concentration of dissolved substances increasing in the non-freezing phase. The process of ice formation and the increase concentration of the remaining liquid continues as it cools to form amorphous (glassy) ice. It is interesting to bring the mass of ice with a further decrease in temperature to (-196) ° C. Cooling causes compression of the formed ice crystals

Application of piezoactuators in the technology of low-temperature preservation of fish reproductive cells

The sperm of Russian sturgeon (Acipenser gueldenstaedtii Brandt et Ratzeburg, 1833) was the research object. Acoustic-mechanical influence on sturgeon semen improves fish-biological and reproductive indices of the seminal fluid. The most optimal indices for reproductive cells of male Russian sturgeon are 500 Hz, 90 V with the exposure duration of 1 minute. It has been shown that when a piezo-actuator with a frequency of 500 Hz and an amplitude of 90 V is applied to the sperm mixture with the cryoprotectant, ice crystals are formed later, which may influence the survival of cells after defrosting

Application of piezoactuators in the technology of low-temperature preservation of fish reproductive cells

The sperm of Russian sturgeon (Acipenser gueldenstaedtii Brandt et Ratzeburg, 1833) was the research object. Acoustic-mechanical influence on sturgeon semen improves fish-biological and reproductive indices of the seminal fluid. The most optimal indices for reproductive cells of male Russian sturgeon are 500 Hz, 90 V with the exposure duration of 1 minute. It has been shown that when a piezo-actuator with a frequency of 500 Hz and an amplitude of 90 V is applied to the sperm mixture with the cryoprotectant, ice crystals are formed later, which may influence the survival of cells after defrosting