In this study, turbulent compressible gas flow in a rectangular micro-channel is numerically investigated. The gas flow assumed to be in the subsonic regime up to Mach number about 0.7. Five low and high Reynolds number RANS turbulence models are used for modeling the turbulent flow. Two types of mesh are generated depending on the employed turbulence model. The computations are performed for R...

The mechanical properties of the microenvironment are being recognized as a key contributor to stem cell behaviour, whether in the context of tissues or when designing biomaterials. While there has been considerable evidence demonstrating the effect of 2-D static mechanics on stem cells, few systems exist to investigate the influence of the 3-D presentation of mechanical signals. In this study,...

OBJECTIVES The aim of this study was to identify the determinants of plaque structural stress (PSS) and the relationship between PSS and plaques with rupture. BACKGROUND Plaque rupture is the most common cause of myocardial infarction, occurring particularly in higher risk lesions such as fibroatheromas. However, prospective intravascular ultrasound-virtual histology studies indicate that <10...

In order to investigate the effects ethanol-diesel blends and altitude on the performance and emissions of diesel engine, the comparative experiments were carried out on the bench of turbo-charged diesel engine fueled with pure diesel (as prototype) and ethanol-diesel blends (E10, E15, E20 and E30) under different atmospheric pressures (81 kPa, 90 kPa and 100 kPa). The experimental results indi...

The effects of precooling, modified atmosphere packaging (MAP) and controlled atmosphere (CA) storage on the storability of snow pea pods (Pisum sati6um L. var. saccharatum) at 5°C were determined. Bagging pods with polymethyl pentene polymeric films (PMP) of 25 and 35 mm thickness, in conjunction with precooling, modified the in-bag atmosphere concentration to approximately 5 kPa O2 and 5 kPa ...

We have studied the effects of extrinsically applied PEEP (PEEPe) and intrinsic PEEP (PEEPi) on lung volume and peak airway pressure (Paw,peak) in 10 patients with airflow limitation during mechanical ventilation. PEEPe was applied in 2-4 cm H2O increments until values greater than PEEPi were reached. Total lung hyperinflation was quantified by measuring the expired volume resulting from deflat...

BACKGROUND To assess correlation between liver or spleen stiffness measurement by transient elastography (TE) and hepatic venous pressure gradient (HVPG) in patients with chronic liver disease as well find optimal and rule in/rule out cut-offs for prognosis of clinically significant (CSPH) and severe (SPH) portal hypertension. METHODS In this prospective study patients with different chronic ...

We hypothesized that KPA, a harmonic oscillator kinematics-derived spring constant parameter of the pulmonary artery pressure (PAP) profile, reflects PA compliance in pediatric patients. In this prospective study of 33 children (age range = 0.5-20 years) with various cardiac diseases, we assessed the novel parameter designated as KPA calculated using the pressure phase plane and the equation KP...

Adult stem cells reside in unique niches that provide vital cues for their survival, self-renewal and differentiation. In order to better understand the contribution of substrate stiffness to neural stem/progenitor cell (NSPC) differentiation and proliferation, a photopolymerizable methacrylamide chitosan (MAC) biomaterial was developed. Photopolymerizable MAC is particularly compelling for the...

viscosity (µ) and density (ρ) are important physical roperties for analysis of membrane processes performance and for designing a new membrane process. in addition, the energy requirement for fluid pumping is depend on these two physical properties magnitiude. in this study, firstly, the effects of different process factors such as transmembrane pressure (51, 101, 152, 203 and 253 kpa), tempera...