A sufficiently general thermally activated mechanism for extension of dislocations in some preferential direction was proposed. This mechanism comprises a necessary step of dislocation transformations that lead to blocking. The reasons for blocking of different types of dislocations in different materials are diverse. A new concept was developed concerning the possibility of thermally activated...

A thin film of heavily B-doped diamond has been grown epitaxially by microwave plasma chemical vapor deposition on an undoped diamond layer, on top of a Ir/YSZ/Si(001) substrate stack, to study the boron segregation and boron environment at the dislocations present in the film. The density and nature of the dislocations were investigated by conventional and weak-beam dark-field transmission ele...

During irradiation, mobile defects, defect clusters and impurity atoms segregate on dislocations. When an external stress is applied, plastic flow is initiated when dislocations are unlocked from segregated defects. Sustained plasticity is achieved by continuation of dislocation motion, overcoming local forces due to dispersed defects and impurities. The phenomena of flow localization, post-yie...

Background The key to a successful result in the treatment of perilunate dislocations (PLDs) and fracture-dislocations (PLFDs) is the restoration of normal alignment of the carpal bones, followed by stable maintenance until healing. This article aimed to assess whether arthroscopic techniques are a reliable surgical option for the treatment of this challenging injury. Materials and Methods Twen...

The purpose of this study was to review clinical and radiographic outcomes of perilunate dislocations and fracture dislocations treated with external fixation and K-wire fixation. Twenty patients (18 males and two females) with a mean age of 38 years (range 18-59) who had an acute dorsal perilunate dislocation or fracture dislocation were treated with the use of wrist external fixator and K-wir...