The question of whether the same acceleration field that is found in a rigid uniformly rotating disc can annul a gravitational field is answered in the negative because their curvatures are different. There is an exact correspondence between a uniformly rotating disc and hyperbolic geometry of constant curvature, while, gravitational fields require non-constant, negative curvature. The connecti...

How to understand the erectile function? How to define erectile dysfunction? In general, erectile function is evaluated by the quality of penile erection. If penis shows good erection, we think erectile function is normal. Otherwise, erectile dysfunction occurs. This concept is reflected in the definition of erectile dysfunction (ED). ED is defined as the persistent inability to attain and main...

The accretion disc around a rotating magnetic star (neutron star, white dwarf or T Tauri star) is subjected to periodic vertical magnetic forces from the star, with the forcing frequency equal to the stellar spin frequency or twice the spin frequency. This gives rise bending waves in the disc that may influence the variabilities of the system. We study the excitation, propagation and dissipatio...

We study jamming in model freely rotating polymers as a function of chain length N and bond angle θ_{0}. The volume fraction at jamming ϕ_{J}(θ_{0}) is minimal for rigid-rodlike chains (θ_{0}=0), and increases monotonically with increasing θ_{0}≤π/2. In contrast to flexible polymers, marginally jammed states of freely rotating polymers are highly hypostatic, even when bond and angle constraints...

ATP synthase is a rotating membrane protein that synthesizes ATP through proton-pumping activity across the membrane. To unveil the mechanical impact of this molecular active pump on the bending properties of its lipid environment, we have functionally reconstituted the ATP synthase in giant unilamellar vesicles and tracked the membrane fluctuations by means of flickering spectroscopy. We find ...

BACKGROUND Biomechanical investigations of spinal motion preserving implants help in the understanding of their in vivo behavior. In this study, we hypothesized that the lumbar spine with implanted total spinal segment replacement (TSSR) would exhibit decreased dynamic stiffness and more rapid energy absorption compared to native functional spinal units under simulated physiologic motion when t...

The aim of this paper is to provide an aeroelastic computational tool which determines the induced wing loads during flapping flight. For this purpose, a Finite Element (FE) code based on a four-node plate bending element formulation is developed to simulate the aeroelastic behavior of flapping wings in low incompressible flow. A quasi-steady aerodynamic model is incorporated into the aeroelast...

The effect of an electroless Ni-Cu-P coating on the fatigue behavior of quenched and tempered CK45 steel has been investigated. The fatigue tests under rotating bending conditions have been conducted in three different conditions of uncoated, as-deposited and shot peened prior to the coating deposition. The results indicate that plating of the base steel leads to a fatigue life reduction. The d...

Performance and reliability of any rotating machine can be studied by proper dynamic analysis of the machine. In this regard, this paper presents the method to study the dynamic response of the shaft of a Pelton turbine due to the impact of water jet. Equations of motion for the bending vibration of Pelton turbine assembly, in two transverse directions, is developed by using Lagrange equation o...