OBJECTIVE To study the degradation and basic fibroblast growth factor (bFGF) release activity of bFGF - poly(lactic-co-glycolic-acid) microsphere (bFGF-PLGA MS) under stress in vitro, including the static pressure and shearing force-simulating mechanical environment of the joint cavity. METHOD First, bFGF-PLGA MSs were created. Meanwhile, two self-made experimental instruments (static pressur...

Strain-rate effects on fracture behavior of unidirectional composite materials are studied. Single-edge notched multi-layered unidirectional graphite composites (T800/3900-2) are investigated to examine fracture responses under static and dynamic loading conditions using a digital speckle correlation method. The fracture parameters for growing cracks are extracted as a function of fiber orienta...

Fusionless devices are currently designed to treat spinal deformities such as scoliosis by the application of a controlled mechanical loading. Growth modulation by dynamic compression was shown to preserve soft tissues. The objective of this in vivo study was to characterize the effect of static vs. dynamic loading on the bone formed during growth modulation. Controlled compression was applied ...

PURPOSE The study of axial loading is essential to determine the properties of intervertebral disc. The objectives of this work are (1) to quantify the mechanical properties of porcine lumbar intervertebral discs under static and cyclic compressive loading, and (2) to determine the parameters of a five-parameter rheological model for porcine and compare them with those obtained for human lumbar...

Vertical drains and stone columns which have been used in infrastructure construction for highways, ports, coastal regions, etc., provide significant benefits for improving soil characteristics such as reducing the drainage length and accelerating the consolidation process. So the investigation of the radial consolidation is inevitable. Soils may be subjected to cyclic loading such as silos, ta...

BACKGROUND For implant-supported hybrid prostheses, high mastication forces and reduced acrylic resin thickness over a metal substructure often cause failures arising from tooth or resin fractures. To assay fracture resistance of artificial teeth and resin in implant-supported hybrid prostheses in relation to the titanium structure and retention design supporting teeth. MATERIAL AND METHODS 4...

BACKGROUND The optimal method for arthroscopic rotator cuff repair is not yet known. The hypothesis of the present study was that a double-row repair would demonstrate superior static and cyclic mechanical behavior when compared with a single-row repair. The specific aims were to measure gap formation at the bone-tendon interface under static creep loading and the ultimate strength and mode of ...

One of the methods for the improvement of soil against the tensile stresses is using the artificial supplements in soil such as metal belts or nets, polymer materials and natural fibers. Technically this method is called the reinforced of soil.  When a pavement is located on soft soil, great deformations can occur as a result of the crossing of traffic load in superstructure layers of the body....