No abstract

The objective was to evaluate the structural and functional quality of bull sperm after sexing by flow cytometry. Frozen non-sexed (NS), sexed for X (SX) and sexed for Y (SY) sperm from four bulls was used. Frozen-thawed sperm was analyzed for motility, sperm head agglutination, morphology, capacitation, and integrity of the plasma membrane, acrosome, and chromatin. After Percoll centrifugation (45:60% gradients), the pellet was used for sperm analysis or IVF. Data were analyzed using generalized linear models (P < 0.05) and were reported as least squares means ± standard error (SEM). Based on sperm evaluations, NS sperm had better (P < 0.05) quality than sexed sperm, including higher motility and greater percentages of cells with an intact membrane and acrosome (58.0 ± 3.0, 58.2 ± 3.0, and 60.9 ± 3.3) than SX (29.6 ± 1.3, 36.0 ± 2.9, and 37.1 ± 3.3), and SY (26.2 ± 2.1, 36.4 ± 2.9, and 37.5 ± 3.3). There were no differences (P > 0.05) among groups for fertilization and cleavage rates. Similarly, blastocyst rate on Day 8 (Day 0 = day of insemination) did not differ among groups (22.2 ± 3.2, 18.1 ± 3.3, and 14.8 ± 2.9 for NS, SX, and SY, respectively). Regarding embryo development kinetics, all groups had similar developmental stages from Days 6 to 9. Although the sex-sorting procedure affected sperm characteristics, it did not significantly affect fertilization or embryo development.

The frequency dependence of the electrical properties of the Bi12TiO20 single crystal was investigated by impedance spectroscopy. The data were presented in the Nyquist diagram form, from which electrical resistivity was determined. Values ranged from 1.93×105 and 1.07×103 Ω cm in the temperature range of 400–700 °C. The electrical conductivity followed the Arrhenius law, with an activation energy of 0.99 eV. The dielectric behavior was investigated from room temperature to 700 °C. Permittivity was calculated based on the relaxation frequency, using an alternative approach based on the variation of the imaginary impedance component as a function of reciprocal angular frequency. The permittivity values obtained by means of these two methods showed good agreement up to 600 °C. The frequency dependence of real and imaginary permittivities from room temperature to 700 °C was also investigated.

Over the past few years of boosting studies in halide perovskites, the formulation of guanidinium (GA+)-containing compounds has been proven to be an excellent strategy. A system in particular, namely...