BACKGROUND We examined the association between quality of care and 30 day mortality in a nationwide cohort of patients hospitalized with hip fracture. METHODS We used data from The Danish National Indicator Project, a quality improvement initiative with participation of more than 90% of Danish hospital departments caring for patients with hip fracture between August 16, 2005 and August 15, 20...

Multi-horizontal well hydraulic fracturing is a widely employed and highly effective method for stimulating tight shale reservoirs. However, most existing studies primarily focus on investigating the impact of intra-well interference fracture propagation while neglecting influence inter-well interference. Here, multi-well hydraulic-fracture-propagation model established to examine effects withi...

The propagation of cracks in graded materials under monotonic and cyclic loading was investigated via experiment and simulation. Graded alumina/epoxy composite specimens exhibiting a variation in composition from 5% to 65% epoxy, representing a twenty-fold variation in Young’s modulus, across a region of width between 6 and 20 mm, were produced by a multistep infiltration technique. Crack initi...

The propagation of fractures during the drying of a colloidal silica suspension confined in a vertical microtube is investigated. During the drying process, the particle concentration increases until gel formation. In the gelled region, the tensile stresses increase and lead to the formation of two vertical perpendicular cracks propagating in the drying direction, dividing the tube into four eq...

In this study, 5052 Al–Mg alloy was pre-treated and friction stir processing (FSP) was then performed on the specimens to explore the deformation resistance. The experimental results indicate that the FSP specimens not only had better tensile properties but also better vibration fracture resistance. It is significant that the tensile elongation and deformation resistance tended to increase as t...

INTRODUCTION The use of noninvasive, acoustic methods like ultrasonometry is becoming increasingly interesting in the quantitative assessment of fracture healing. A reliable measurement technique has been described using ultrasonic transducers placed across the fracture gap. Ultrasonic image aiming is useful for accurate transducers location, on both sides of the gap. The study was designed to ...

In the present research, a fully Automatic crack propagation as one of the most complicated issues in fracture mechanics is studied whether there is an inclusion or no inclusion in the structures. In this study The Extended Finite Element Method (XFEM) is utilized because of several drawbacks in standard finite element method in crack propagation modeling. Estimated Crack paths are obtained by ...

Due to concerns over particle generation in conventional metal-on-polyethylene hip bearings used in total hip arthroplasty (THA), interest in advanced low-wear bearing alternatives such as ceramic-on-ceramic (CoC) couples has reemerged. While ceramics demonstrate excellent compressive strength, the brittle nature of the material reduces tensile strength, possibly leading to catastrophic fractur...

Background: Gradient damage models can be acknowledged as a unified framework of dynamic brittle fracture. As a phase-field approach to fracture, they are gaining popularity over the last few years in the computational mechanics community. This paper concentrates on a better understanding of these models. We will highlight their properties during the initiation and propagation phases of defect ...

Significant work in the past few decades has lead to a well developed understanding of seismic wave propagation in fractured media. However, previous research has focused on fractures within rock as opposed to fractures at the surface of a rock. A theoretical and experimental study was performed to examine seismic wave propagation along a fracture at the surface, i.e., along the intersection of...