Finite element (FE) models are advantageous in the study of intervertebral disc mechanics as the stress-strain distributions can be determined throughout the tissue and the applied loading and material properties can be controlled and modified. However, the complicated nature of the disc presents a challenge in developing an accurate and predictive disc model, which has led to limitations in FE...

Endoscopic discectomy entails use of an imaging-guided probe inserted between the vertebrae and into the herniated disc space. Microsurgical attachments routed through the endoscope remove a portion of the nucleus tissue of the compromised disc; the amount excised depends on various circumstances but never affects the disc’s support structure. It is also possible to use the instrument to manipu...

Accretion disc coronae (ADC) sources are very high inclination neutron star or black hole binaries, where the outer accretion flow blocks a direct view of central source. The weak observed X-ray emission is instead produced mainly by scattering intrinsic radiation from highly ionised gas surrounding source, ADC. However, origin this material still under debate. We use ADC source 2S 0921-630 (V3...

We present a pseudo-Newtonian potential for accretion disk modeling around the rotating black holes. This potential can describe the general relativistic effects on accretion disk. As the inclusion of rotation in a proper way is very important at an inner edge of disk the potential is derived from the Kerr metric. This potential can reproduce all the essential properties of general relativity w...

Some of the X–ray temporal and spectral properties of accreting black holes represent a challenge for current theoretical models. In particular, uncorrelated variability between direct continuum and reflection components (including the iron line, if present) has been reported in many cases. Here, we explore a light bending model in which we assume a primary source of X–rays located close to a c...

General Relativistic (GR) Magnetohydrodynamic (MHD) simulations of black hole accretion find significant magnetic stresses near and inside the innermost stable circular orbit (ISCO), suggesting that such flows could radiate in a manner noticeably different from the prediction of the standard model, which assumes that there are no stresses in that region. We provide estimates of how phenomenolog...

This is the second of a series of papers investigating the oscillation properties of relativistic, non-selfgravitating tori orbiting around black holes. Extending the work done in a Schwarzschild background, we here consider the axisymmetric oscillations of vertically integrated tori in a Kerr spacetime. The tori are modeled with a number of different non-Keplerian distributions of specific ang...

The entropy of anti-de Sitter Reissner-Nordström black hole is found to be stored in the material which gathers to form it and equals to A/4 regardless of material states. Extending the study to two kinds of extreme black holes, we find different entropy results for the first kind of extreme black hole due to different material states. However for the second kind of extreme black hole the resul...

Finite element (FE) models have become an important tool to study load distribution in the healthy and degenerated disc. However, model predictions require accurate constitutive laws and material properties. As the mechanical properties of the intervertebral disc are regulated by its biochemical composition and fiber-reinforced structure, the relationship between the constitutive behavior of th...