An assessment is made here of the role played by the micropolar continuum theory on the cracked Brazilian disc test used for determining rock fracture toughness. By analytically solving the corresponding mixed boundary-value problems and employing singular-perturbation arguments, we provide closed-form expressions for the energy release rate and the corresponding stress-intensity factors for bo...

Concrete is a brittle material whose tensile strength about one-tenth of its compressive strength. Tensile key parameter for concrete under impact loading. When turning point occurs before peak load in the load–time curve from dynamic Brazilian disc test, there no basis choosing or to calculate The objective this study determining crack initiation stress at peak. method contrasts time duration ...

statement of problem: as a physical property, wear resistance of the materials used in the fabrication of orthodontic retainers play a significant role in the stability and long term use of the appliances. objectives: to evaluate the wear resistance of two commonly used materials for orthodontic retainers: acropars op, i.e. a polymethyl methacrylate based material, and 3a-gs060, i.e. a polyethy...

OBJECTIVES The study investigated the impact of occupational workloads on disc surgery specimens. We report the relationship between workload and histological features. METHODS Specimens were collected prospectively from patients suffering from lumbar disc prolapse (n=90) or spinal osteochondrosis (n=19). Histomorphology and occupational workload data and histomorphological features were eval...

introduction: this study is aimed to compare phenotypic test methods and determine antibiotic susceptibility pattern of ampc beta-lactamase producing uropathogenic escherichia coli and klebsiella pneumoniae in clinical isolates. method: e. coli and k. pneumoniae were identified by standard microbiological procedures. screening of ampc beta-lactamase production was done by using cefoxitin disc (...

Mode I fracture toughness (KIC) is an intrinsic material property that quantifies its resistance to tensile propagation. The International Society for Rock Mechanics has endorsed four methods determine the KIC of rock, namely, short rod, chevron bend, cracked notched Brazilian disc, and semi-circular bend (SCB) methods. In this study, we compare results SCB technique with those recently propose...

A 75-year-old male with rheumatoid arthritis complained of proptosis of the left eye. On examination, 6-mm left proptosis was seen. A hyperemic and swollen optic disc was visible in the left fundus. Laboratory test results showed positive rheumatoid factor. Computed tomography and magnetic resonance imaging showed a mass lesion in the left orbit. Histopathologic study of the excised specimen re...