Morphokinetic characteristics of embryos derived from in-vitro-matured oocytes and their in-vivo-matured siblings after ovarian stimulation.

Research Question: Does delayed maturation of aspirated metaphase I (MI) oocytes, completed in vitro, adversely affect early embryo development?

Design: Time-lapse microscopy was used to compare morphokinetic variables between embryos derived from oocytes with delayed maturation after ovarian stimulation and from in-vivo-matured metaphase II (MII) sibling oocytes from the same IVF and intracytoplasmic sperm injection cycle.

Results: A total of 1545 injected oocytes in 169 cycles from 149 patients were included. The in-vitro-matured oocytes had lower normal fertilization rates than the MII aspirated oocytes (50.

Prolonging oocyte in vitro culture and handling time does not compensate for a shorter interval from human chorionic gonadotropin administration to oocyte pickup.

Objective: To assess the impact of oocyte aspiration, denudation, and sperm injection timing in relation to oocyte hCG exposure time on intracytoplasmic sperm injection (ICSI) outcome.

Design: Cohort study.

Setting: Tertiary medical center.

[Efficiency of a visual system under conditions of uncertainty of the appearance of a moving object].

The effect of uncertainty of a moving object appearance in the noise field upon the coefficient efficiency, we studied. At short durations of presentation (40-80 msec) and high level of external noise, this effect was maximal: magnified 100 times. The efficiency coefficient dependence on the duration of a moving object presentation was shown to be characterized by two maximums.

[Principle of least action, physiology of vision, and conditioned reflexes theory].

The variation principles such as principle of least action by Maupertuis (1740) and Fermat principle (1660) are fundamental for physics. They permit to establish a property by which the actual state is differing from all possible states of the system. The variation approach permits to establish equation of motion and equilibrium of a material system on the basis of one common rule which reduces to the search of the function extremes, describes this property of the system.