Background: Mammalian sperm are not ready to fertilize oocyte immediately after ejaculation. Sperm achieve this ability after undergoing the processes of capacitation and hyperactivation. Hyperactivation refers to a change in the motility pattern of the sperm. Pharmacological reagents and physical-mechanical forces have been used in sperm from a variety of species. Hydrostatic pressure is a cru...

BACKGROUND/AIMS Mechanical forces are thought to induce cellular responses through activation of signalling pathways. Cells within the intraocular environment are exposed to constant changes in the levels of intraocular pressure. In this study, an attempt was made to determine the acute effects of elevated hydrostatic pressure on different intraocular cells grown in culture. METHODS Different...

The results obtained from the experimental testing of hoop wound S-2 GlasdEpoxy and AS41 PPS composite rings are presented here. In this study, the effects of different material system and thickness on failure are investigated. A custom, volume controlled pressurization set-up was designed and built for the tests. Initial imperfection in the ring specimens were measured prior to testing and the...

We present thermally regenerated fiber Bragg gratings in air-hole microstructured fibers for high-temperature, hydrostatic pressure measurements. High-temperature stable gratings were regenerated during an 800 °C annealing process from hydrogen-loaded Type I seed gratings. The wavelength shifts and separation of grating peaks were studied as functions of external hydrostatic pressure from 15 to...

objective: hydrostatic pressure is crucial component of cell environment and fundamental physical quantity, also it is the main factor of both cell integrity and function. pressure variation disorder, beyond physiological limits, may lead to pathological states. in this study, we examined the effect of hydrostatic pressure on apoptosis induction, viability, morphology, adhesion potency to subst...

Theoretical calculations on the influence of both an external electric field and hydrostatic stress on the binding energy and impurity polarizability of shallowdonor impurities in an isolated GaAs–(Ga, Al)As quantum well are presented. A variational procedure within the effective-mass approximation is considered. The pressure-related –X crossover is taken into account. As a general feature, we ...

purpose : to investigate the effects of mtp-131 on trabeculum cells cultured under hydrostatic pressure methods : glaucomatous human trabecular meshwork (gtm3) cells were divided into three groups: the mtp-131 group, the hydrostatic group, and the normal group. the mtp-131 group was pretreated with 1 µm mtp-131, and the cells were then cultured under 80 mmhg pressure for 24 hours. the normal gr...

This study investigates the buckling behavior of short cylindrical shells with hemi-spherical heads subjected to hydrostatic pressure. It is assumed that the length of the cylindrical part is smaller than or equal to its diameter while its material may be dif-ferent from that of hemispherical heads. Finite element analysis was used to seek out the effect of geometric parameters such as thicknes...

In this paper, drain-source current, transconductance and cutoff frequency in AlGaN/GaN high electron mobility transistors have been investigated. In order to obtain parameters of exact AlGaN/GaN high electron mobility transistors such as electron density, the wave function, band gap, polarization charge, effective mass and dielectric constant, the hydrostatic pressure and temperature effects a...