BASEBALL SPIN AND PITCHERS’ PERFORMANCE

The motion of the ball thrown by a pitcher is influenced by three forces: gravity, drag force due to air resistance, and lift force which deflects a ball vertically or laterally due to ball spin. The lift force acting on the ball increases with spin rate and movement speed when the spin axis of the ball is orthogonal to the direction of ball movement. Among individual pitchers there were great variations in spin on their fastballs, both in spin rate and in direction of the spin axis. Ball spin rate was positively correlated with increases in distance from the optimal contact point of the swung bat (sweet spot) to the actual point of contact. That is, batters tend to hit under the ball when it has a high spin rate, even for balls of the same velocity. Abnormal or unique ball spin is an important aspect of superior performance for pitchers

Rapid-onset dystonia-Parkinsonism phenotype consistency for a novel variant of ATP1A3 in patients across 3 global populations

info:eu-repo/semantics/publishedVersio

A Simplified Method for Three-Dimensional (3-D) Ovarian Tissue Culture Yielding Oocytes Competent to Produce Full-Term Offspring in Mice.

In vitro growth of follicles is a promising technology to generate large quantities of competent oocytes from immature follicles and could expand the potential of assisted reproductive technologies (ART). Isolated follicle culture is currently the primary method used to develop and mature follicles in vitro. However, this procedure typically requires complicated, time-consuming procedures, as well as destruction of the normal ovarian microenvironment. Here we describe a simplified 3-D ovarian culture system that can be used to mature multilayered secondary follicles into antral follicles, generating developmentally competent oocytes in vitro. Ovaries recovered from mice at 14 days of age were cut into 8 pieces and placed onto a thick Matrigel drop (3-D culture) for 10 days of culture. As a control, ovarian pieces were cultured on a membrane filter without any Matrigel drop (Membrane culture). We also evaluated the effect of activin A treatment on follicle growth within the ovarian pieces with or without Matrigel support. Thus we tested four different culture conditions: C (Membrane/activin-), A (Membrane/activin+), M (Matrigel/activin-), and M+A (Matrigel/activin+). We found that the cultured follicles and oocytes steadily increased in size regardless of the culture condition used. However, antral cavity formation occurred only in the follicles grown in the 3-D culture system (M, M+A). Following ovarian tissue culture, full-grown GV oocytes were isolated from the larger follicles to evaluate their developmental competence by subjecting them to in vitro maturation (IVM) and in vitro fertilization (IVF). Maturation and fertilization rates were higher using oocytes grown in 3-D culture (M, M+A) than with those grown in membrane culture (C, A). In particular, activin A treatment further improved 3-D culture (M+A) success. Following IVF, two-cell embryos were transferred to recipients to generate full-term offspring. In summary, this simple and easy 3-D ovarian culture system using a Matrigel drop and activin A supplementation (M+A) provides optimal and convenient conditions to support growth of developmentally competent oocytes in vitro

Body and Placenta Weights of Newborn Offspring Derived from Oocytes Grown under 4 Different Ovarian Culture Conditions.

<p>* <i>In vivo</i> control pups were derived from natural mating between B6D2F1 female and male mice.</p><p>Body and Placenta Weights of Newborn Offspring Derived from Oocytes Grown under 4 Different Ovarian Culture Conditions.</p

Histological analysis of ovarian tissues under Membrane or 3-D culture system.

<p><b>(a, b)</b> Paraffin sections of a whole murine ovary at 14 dpp (a) and 24 dpp (b) with a HE staining. <b>(c, e, g)</b> The ovarian tissues cultured in the Membrane culture system (C condition) for 10 days. <b>(d, f, h)</b> The ovarian tissues cultured in the 3-D culture system (M+A condition) for 10 days. Follicle growth was detected in both culture systems. Importantly, the antral cavity formation (arrows) occurred only in the 3-D culture system (M, M+A) regardless of the presence or absence of activin A treatment. Regular bar = 200 μm. Bold bar = 100 μm.</p

Two-Cell Development after <i>In Vitro</i> Fertilization of Oocytes Grown under 4 Different Ovarian Culture Conditions.

<p>Values with different superscripts within the same column are significantly different (a-c: <i>P</i><0.01; b, c: <i>P</i><0.02).</p><p>Two-Cell Development after <i>In Vitro</i> Fertilization of Oocytes Grown under 4 Different Ovarian Culture Conditions.</p