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Stable dispersions of gold ([Au.sup.0]) nanoparticles are produced in a few commercially important thermoplastics using a novel surface infusion technique. The thermoplastic article is immersed in a dilute solution of [HAuCl.sub.4] in a ternary solvent mixture held well below the melt-processing temperature of the plastic. Rapid infusion of plasticizing solvents and [HAuCl.sub.4] is achieved for several thermoplastic polyurethane elastomers and an acrylic-pyrrolidinone copolymer. A second infusion of triethylamine, a reducing agent, produces [Au.sup.0] nanoparticles in a surface layer of (10-30 µm) depth. Precipitation of [Au.sup.0] nanoparticles is arrested by the high viscosity of the plasticized polymer matrix, resulting in a stable dispersion, but formation of aggregates is possible in some plastics. The [Au.sup.0] particle size distribution can be manipulated by changing processing conditions that affect the formation of aggregates, such as the concentrations of [HAuCl.sub.4] and plasticizers. POLYM. ENG. SCI., 50:120-127, 2010. [C]2009 Society of Plastics Engineers, INTRODUCTION Polymer-inorganic nanocomposites are an emerging class of materials that combine the mechanical properties and processability of polymers with the optical, electrical, barrier, and other engineering properties of inorganic nanoparticles. [...]

Discusses the state of psychoanalysis in the area of managed care in the U.S. Factors contributing to the condition of the community; Emergence of the psychosocial model of psychiatry during the 1950s and the 1960s; Challenges facing psychoanalysts.