in the last decade, decrease of the wear rate, increase in the axel load, and the velocity of the trains have changed the main damage mechanism of railway wheels from wear to rolling contact fatigue (rcf). rcf may lead to surface and subsurface cracks. the interaction between wear and rcf, removes the surface cracks, but the subsurface crack propagate gradually, and may lead to deeper and more ...

Gabapentin seems to be a safe and well tolerated medication for treating heroine dependence. This study examined the efficacy of gabapentin for relieving withdrawal-related pain due to heroin use.Sixty men were recruited from an inpatient psychiatric ward of Fatemieh hospital in Semnan and randomized to receive either placebo (n = 30) or gabapentin (1800 mg/day) (n = 30) for 7 days. Subjective ...

Iranian crack is a new form of narcotic substance that has found widespread prevalence inIran in the past years. crack only nominally resembles crack cocaine as it is widely different inits clinical signs. Thus the present study aims to quantify the chemical combination of this drug.The samples included 18 specimen of crack collected from different zones of Tehran, Iran.All specimens were in th...

Iranian crack is a new form of narcotic substance that has found widespread prevalence inIran in the past years. crack only nominally resembles crack cocaine as it is widely different inits clinical signs. Thus the present study aims to quantify the chemical combination of this drug.The samples included 18 specimen of crack collected from different zones of Tehran, Iran.All specimens were in th...

A Pseudomonas aeruginosa strain (UCBPP-PA14) is infectious both in an Arabidopsis thaliana leaf infiltration model and in a mouse full-thickness skin burn model. UCBPP-PA14 exhibits ecotype specificity for Arabidopsis, causing a range of symptoms from none to severe in four different ecotypes. In the mouse model, UCBPP-PA14 is as lethal as other well-studied P. aeruginosa strains. Mutations in ...

the cracked brazilian disc (cbd) specimen is widely used in order to determine mode-i/ii and mixed-mode fracture toughness of a rock medium. in this study, the stress intensity factor (sif) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (x-fem). this method is based upon the finite element method (fem). in this m...

the prevalent method of irrigation in paddy fields in iran is continuous ponding, which changes to intermittent method at the time of water shortage. soil cracks are the main problem in intermittent irrigation. in this study, effects of adding rice straw on some soil physical characteristics and cracks were studied in paddy soils of the guilan province of iran. the experiment was performed as s...

A novel method for preparing and testing bending specimens in-situ the TEM has been developed. This method provides high visibility of the crack front and its associated plastic zone. This is significant because energy release rates can now be calculated at many points throughout the test based on crack tip opening displacement (CTOD), crack opening angle (COA), and crack advance. Further refin...

In this work, the plastic deformation mechanisms responsible for mechanical properties and fracture toughness in nanotwinned (NT) magnesium is studied by molecular dynamics (MD) simulation. The influence of twin boundary (TBs) spacing and crack position on deformation behaviors are investigated. The microstructure evolution at the crack tip are not exactly the same for the left edge crack (LEC)...