The existing experimental data concerning the Size Effects on the fracture parameters [1] were analyzed, in order to check the validity of certain theoretical models. In this aim, the present work studied: a) the use of some rigorous statistical tests in order to eliminate the “rough” errors, b) different theoretical models (e.g. the Bazant’s Size Effect Law (SEL) [2], the Modified Size Effect ...

It is vital for the study of fracturing parameters optimal design and fluids rate forecast to calculate fracture propagation parameters accurately. In order to calculate fracture propagation accurately, in this paper, the model for calculating the value of energy release when the rock body collapses was established basing on catastrophe theory, considering that the collapse of fracturing rock b...

since bone marrow has been shown to contain osteoprogenitor cells, an experiment was devised to test its effects when injected percutaneously into osteotomies sites in rabbit radii. in this experimental study, the osteogenicity and its effect on early bone repair of bone marrow grafts were investigated. the purpose of this study was to determine whether bone marrow grafted percutaneously led to...

OBJECTIVE To compare the use of crossed K-wire and prebent intramedullary nail techniques for the fixation of distal radius metaphyseal fracture in children. METHODS Intraoperative and follow-up data for children with distal radius metaphyseal fracture, treated using crossed K-wire or prebent intramedullary nail fixation, were retrospectively analysed. Patient groups were matched for age, sex...

1. Problem formulation. The processes governing the fracture of brittle solids are, at present, much less illuminated than those related to plastic deformations. The reason is that it is very difficult to observe the detailed fracture process directly. All one can determine is the load, which acted immediately before fracture started, and the path and nature of the fracture surface. Because dur...

BACKGROUND The purpose of the current study was to examine objective and subjective differences between three severity groups of ankle fractures patients compared to healthy controls. METHODS This was a case-controlled study. 92 patients with an ankle fracture injury of which 41 patients were eligible to participate in the study. 72 healthy people served as controls. All patients underwent a ...

Waves reflected from and transmitted across fault zones can be used to extract information on those zones. Fault zones, characterized as either a low-velocity zone or fracture systems, modify the phase of the waveform and make the seismic response frequency dependent. In this paper we develop an extrapolation scheme for simulating fractures described as linear slip boundaries. Two 9 × 9 linear ...

Many fractures occur in individuals without osteoporosis defined by areal bone mineral density (aBMD). Inclusion of other aspects of skeletal strength may be useful in identifying at-risk subjects. We used surrogate measures of bone strength at the radius and tibia measured by peripheral quantitative computed tomography (pQCT) to evaluate their relationships with nonvertebral fracture risk. Fem...

OBJECTIVE To analyze whether association between bone fragility and risk of fracture depends on the trauma level. METHOD All participants along with their mothers underwent DXA scan and body measurements. The subjects answered a self-report questionnaire about their physical activities and the precipitating causes. The questionnaire results were associated with DXA performed at the baseline v...