ASTM F-75 Cobalt-base alloy castings are widely used for manufacturing orthopedic implants. This alloy needs both homogenization and solutionizing heat treatment after casting, as well as bioactivation of the surface to increase the ability of tissue bonding. In this study, ASTM F-75 Cobalt-base substrate was heat treated at 1220°C for 1 hour in contact with Hydroxyapatite-Bioglass powder in or...

We derive dynamic optimal trading strategies that minimize the expected cost of trading a large block of equity over a fixed time horizon. Specifically, given a fixed block SM of shares to be executed within a fixed finite number of periods 1, and given a price-impact function that yields the execution price of an individual trade as a function of the shares traded and market conditions, we obt...

In this work, the mechanism for fracture of brittle substances such as rocks under a uniform normal tension is considered. The oriented straight micro-cracks are mostly created in all the polycrystalline materials resulting from the stress concentrations. The present work focuses on the interactions of the pre-existing micro-cracks, which can grow and propagate within a rock-like specimen. The ...

One hundred and five stoma biopsy specimens and 108 corpus biopsy specimens from 108 patients who had undergone a partial gastrectomy because of peptic ulcer disease were examined retrospectively for the presence of Campylobacter-like organisms and gastritis. In the corpus biopsy specimens Campylobacter-associated gastritis was found in 55 (71%) of the cases and in 42 (48%) of the stoma biopsy ...

Iranian crack is a new form of narcotic substance that has found widespread prevalence inIran in the past years. crack only nominally resembles crack cocaine as it is widely different inits clinical signs. Thus the present study aims to quantify the chemical combination of this drug.The samples included 18 specimen of crack collected from different zones of Tehran, Iran.All specimens were in th...