the high blood rate that often occurs in arteries may play a role in artery failure and tortuosity which leads to blackouts, transitory ischemic attacks and other diseases. however, vibration and instability analysis of carotid arteries are lacking. the objective of this study is to investigate the vibration and instability of the carotid arteries conveying blood under axial tension with surrou...

in this paper the effects of non-linearity of suspension on dynamic behavior of a railway wheelset has been studied. this wheelset has four degrees of freedom that with two constraints it has reduced to two degrees of freedom. vermeulen-johnson theory has been used to calculate contact forces between wheel and rail. in this study the creep coefficients have considered constant. any linearizatio...

conclusions results suggest that these methods cannot be interchanged, and vvi showed significantly lower lv peak twist, peak twisting rate and peak untwisting rate. however, when lv twist and lv twisting rates were normalized to lv length, values were comparable for both imaging techniques. results twist degree was significantly lower in the vvi group than in the tdi group (p = 0.008, r = 0.56...

The aims of the present study were to assess critical velocity using the swimmer curriculum in front crawl events and to compare critical velocity to the velocity corresponding to a 4 mmol·l(-1) of blood lactate concentration and to the velocity of a 30 min test. The sample included 24 high level male swimmers ranged between 14 and 16 years old. For each subject the critical velocity, the veloc...

The high blood rate that often occurs in arteries may play a role in artery failure and tortuosity which leads to blackouts, transitory ischemic attacks and other diseases. However, vibration and instability analysis of carotid arteries are lacking. The objective of this study is to investigate the vibration and instability of the carotid arteries conveying blood under axial tension with surrou...

in this paper, nonlinear dynamic behaviours of carbon nanotube conveying fluidwith slip boundary conditions is studied using variation iteration method. the developed solutions are used to investigate the effects of various parameters on the nonlinear vibration of the nanotube. from the result, it is observed that increase in the slip parameter leads to decrease in the frequency of vibration an...

background: pulse wave velocity (pwv) is widely used for estimating the stiffness of an artery. v arious invasive and non-invasive methods have been developed to determine pwv over the years. in the present research , the non-invasive estimation of the pwv of large arteries was used as an index for arterial stiffness. methods: a dynamic model based on the navier-stokes equations coupled to elas...

magnesium alloys in liquid-phase condition form surface oxide films due to their high rate of oxidation. oxide films enter the melt as a result of surface turbulence, and remain inside the workpiece after solidification. the incoherent nature of their interface causes decreases in mechanical properties and reliability of castings. the effect of critical velocity and greater velocities of enteri...

purpose: to compare ophthalmic artery velocity in eyes with nonarteritic anterior ischemic optic neuropathy (naion) with that of normal fellow eyes. methods: in this case-control study, 20 patients with unilateral naion and disease onset less than 8 weeks, were enrolled. using color doppler imaging, mean, maximum systolic and end diastolic ophthalmic artery velocities were evaluated. the result...