polymer/clay nanocomposites are considered as a new subject of research in iran and the world. addition of a minimum amount of clay (2-5wt%) can improve the mechanical properties, enhance barrier properties and reduce flammability dramatically. polystyrene (ps) exhibits high strength, high modulus and excellent dimensional stability, but it has poor ductility, elongation, and flexural modulus. ...

IMPORTANCE Transcatheter aortic valve replacement (TAVR) is an effective treatment option for high-risk patients with severe aortic stenosis. Different from surgery, transcatheter deployment of valves requires either a balloon-expandable or self-expandable system. A randomized comparison of these 2 systems has not been performed. OBJECTIVE To determine whether the balloon-expandable device is...

Increasing requirements are leading to new developments in bead foam materials. Engineering thermoplastics such as polybutylene terephthalate (PBT) outperform standard foams thermal stability. In order obtain molded parts, beads fused together using steam chest molding. Classical theories for the fusion mechanism, explaining molding of amorphous EPS (expandable polystyrene) or semi-crystalline ...

abdominal aortic coarctation is an extremely rare vascular pathology. its etiology can be congenital or acquired. here we present a case of acquired infrarenal abdominal coarctation in a 66-year-old woman who complained of low back and legs pain. she had no signs of resting lower limb ischemia, with diminished distal pulses and normal blood pressure in upper and lower extremities. magnetic reso...

BACKGROUND Expandable screws have greater pullout strength than conventional screws. The purpose of this study was to compare the biomechanical stability provided by a new built-in expandable anterior spinal fixation system with that of 2 commonly used anterior fixation systems, the Z-Plate and the Kaneda, in a porcine partial vertebral corpectomy model. METHODS Eighteen porcine thoracolumbar...

OBJECTIVES Several endoscopic techniques have been proposed for the management of post-sphincterotomy bleeding. Lately, self-expandable metal stents deployment has gained popularity especially as a rescue therapy when other endoscopic techniques fail. METHODS-RESULTS We report the case report of a massive post-sphincterotomy bleeding in a patient with a self-expandable metal stent in the bili...

A new and general approach is proposed to analyze the dynamics of a colloidal particle interacting with a nearby wall. This analysis can be used to determine the acting forces even when the system is non-stationary. As an illustration, we use total internal reflection microscopy to investigate the forces acting on a polystyrene sulfate latex particle as it is receding from a charged glass surface.

In this work, we prepared and investigated two series of polymer composites, wherein the matrix was either an amorphous polystyrene (PS) or a semicrystalline high-density polyethylene (HDPE) filled with expandable graphite (EGr) at relatively high loadings within range 5–55 wt %. For investigation employed thermogravimetric analysis differential scanning calorimetry to assess thermal transition...

Post-harvest loss continues to be a significant problem in the food industry. Different packaging materials, designed reduce fruit damage, are anticipated for various applications supply chain. Recently, stamped paper (SP) and expandable polystyrene (EPS) trays have been introduced as tomato retail packaging. Although combination of clear plastic still not 100% biodegradable packaging, they pro...