Kienbock's disease, which is an idiopathic osteonecrosis and collapse of the lunate bone, is an uncommon disease in children. This report describes a case of an 11-year-old girl, who presented with avascular necrosis of lunate bone confirmed by radiographic and magnetic resonance imaging evidence. After a short period of casting, the case was fully recovered within one year. The signal change w...

The standard approaches to solving overdetermined linear systems Ax ≈ b construct minimal corrections to the data to make the corrected system compatible. In ordinary least squares (LS) the correction is restricted to the right hand side b, while in scaled total least squares (Scaled TLS) [10; 7] corrections to both b and A are allowed, and their relative sizes are determined by a real positive...

Analysis of radiographs of 52 wrists showed that, from ulnar to radial deviation, the amount of scaphoid shortening and ulnar translation of the scaphoid varies in a normal distribution. There is a significant correlation between the two measurements, such that the more the scaphoid shortens the less it translates and vice versa. Females subjects were more likely to have greater scaphoid shorte...

Single or repetitive microfractures leading to vascular disruption of the fragments. Recurrent compression of the lunate between capitate and distal radius. Extreme wrist positions or repetitive compression loading of the wrist. Negative ulnar variance, which occurs when the ulna projects more proximally than the radius, leading to increased load transmission through the radio-lunate joint. Var...

     This research has attempted to measure the parameters of barchan dunes as one of the desert landforms. This has been conducted by a field survey using cartographic techniques. In the field, two barchan dunes have completely been surveyed by total station equipment. Using the sample points a novel method has been devised to measure the barchans parameters. The method is mainly based on geom...

INTRODUCTION Kienbock's disease is an osteonecrosis of lunate bone (lunatomalacia) seen more commonly in males in the second to fourth decade of life. The exact etiology is unknown and symptoms include wrist pain and stiffness of wrist. Advanced stages of disease may require lunate excision and filling of the void by various substitutes like silicone implants, tendon grafts etc. We report a cas...

Sand dunes are often covered by vegetation and biogenic crusts. Despite their significant role in dune stabilization, biogenic crusts have rarely been considered in model studies of dune dynamics. Using a simple model, we study the existence and stability ranges of different dune-cover states along gradients of rainfall and wind power. Two ranges of alternative stable states are identified: fix...

Barchan dunes are found where sand availability is low and wind direction quite constant. The two dimensional shear stress of the wind field and the sand movement by saltation and avalanches over a barchan dune are simulated. The model with one dimensional shear stress is extended including surface diffusion and lateral shear stress. The resulting final shape is compared to the results of the m...