We report measurements of three-wave mixing amplitudes on systems whose third order elastic constants have also been measured by means of the elastoacoustic effect. Because attenuation and diffraction are an important aspect of our measurement technique we analyze our results using a modified Khoklhov-Zabolotskaya-Kuznetsov equation in the frequency domain. We find that the value of beta so ded...

objectives: the aim of this study was to assess and compare the water sorption and flexural strength of thermoplastic and conventional acrylic resins. materials and methods: water sorption and flexural strength were compared between a thermoplastic modified polymethyl methacrylate (pmma) denture base resin (group a) and a heat-polymerized pmma acrylic resin (group b) as the control group (n=10)...

polymethyl methacrylate (pmma), widely used as a prosthodontic base, has many disadvantages, including a high thermal expansion coefficient and low thermal conductivity, a low elasticity coefficient, low impact strength and low resistance to fatigue. this study aimed to make an in vitro comparison of the thermal conductivity, compressive strength, and tensile strength of the acrylic base of com...

Background. The objective of our study was to evaluate the stabilization of reconstructed long bones after metastatic tumor resection and defect filling with polymethyl methacrylate (PMMA) or bone allograft. Material and methods. We studied a group of 107 patients who underwent surgery between 1996 and 2004 (55 females and 46 males). A primary neoplasmatic focus was found after histopathologica...

In this retrospective study, surgical results of four patients with sacral tumors having disparate pathologic diagnoses, who were treated with partial or total sacrectomy and lumbopelvic stabilization were abstracted. Two patients were treated with partial sacral resection and two patients were treated with total sacrectomy and spinopelvic fixation. Fixation methods included spinopelvic fixatio...

Reducing the recombination probability of photogenerated electrons and holes is pivotal in enhancing the photocatalytic ability of graphitic carbon nitride (g-C3N4). Speeding the departure of photogenerated electrons is the most commonly used method of achieving this. To the best of our knowledge, there is no report on suppressing the recombination of photogenerated electron-hole pairs by immob...

Frontobasal injuries and some other diseases of frontal sinuses sometimes require radical surgery with the obliteration of the sinus. A cosmetic correction of the forehead and supraorbital arches has to be performed after such a procedure. Nowadays, there is a wide choice of alloplastic materials on the market. We tried polymethyl methacrylate implants in correction of the exterior appearance o...