This work presents a rigorous mathematical formulation for topology optimization of macrostructure undergoing ductile failure. The prediction solid materials which exhibit dominant plastic deformation is an intriguingly challenging task and plays extremely important role in various engineering applications. Here, we rely on the phase-field approach to fracture widely adopted framework modeling ...

OBJECTIVE To evaluate the effect of number of uses, angle and radius of curvature and type of instrument on the fracture of ProTaper rotary instruments when used by undergraduate students. STUDY DESIGN Three hundred and seventy-six molars, with a total of 1114 root canals, extracted were instrumented by undergraduate students using ProTaper instruments according to the manufacturer´s recommen...

The Earth’s electric field transient variations are promising candidates of earthquake precursors. In order to study the physical mechanisms of such precursory signals, laboratory experiments of uniaxial compression were carried out. More specifically the behaviour of stressed marble samples from Penteli Mountain was investigated. The samples were subjected to a time-varying uniaxial compressio...

BACKGROUND AND PURPOSE Falling with a femur fracture is a serious event that negatively affects the quality of life of elderly individuals as well as patients with parkinsonism. This study investigated the association between parkinsonism and femur fracture and compared the risk of femur fracture between subjects with and without parkinsonism. METHODS This study examined a population-based ma...

In the aerospace industry, fracture requirements are usually expressed in a document titled "Fracture Control Implementation Plan (FCIP)." The plan specifies the fracture control criteria and procedures to be implemented on a specific program. The primary objective of these controls is to preclude flaw-induced structural failures that could imperil a mission or a Space Transportation System and...

BACKGROUND In metastatic bone disease, prophylactic fixation of impending long bone fracture is preferred over surgical treatment of a manifest fracture. There are no reliable guidelines for prediction of pathological fracture risk, however. We aimed to determine whether finite element (FE) models constructed from quantitative CT scans could be used for predicting pathological fracture load and...

OBJECTIVE The aim of this study was to determine how physical and morphological properties affect the fracture resistance of roots, and which criteria are important for root specimen standardization in fracture resistance studies. MATERIALS AND METHODS Seventy-five freshly extracted human canine teeth were selected. Crowns were sectioned from the cement-enamel junction and the root lengths we...

it has been reported that fractures are more common in epileptic patients relative to the general population. seizures by repeated muscular contractions can increase fracture risk throughout the skeleton, but the reported papers about non traumatic vertebral fractures following a single episode of seizure are rare and mostly located in thoracic spine with only one or two vertebral fracture. the...

background: the main purpose of this study was to determine the relationship between serum vitamin d and the status of bone mineral density in patients with low-energy hip and distal radius fracture. methods: this retrospective case-control study was performed between january 2013 and january 2014. participants aged 55 years or older were divided to case group including 85 patients with low-ene...