We develop a dynamic equilibrium model of labor demand with adverse selection. Firms learn the quality of newly hired workers after a period of employment. Adverse selection makes it costly to hire new workers and to release productive workers. As a result, firms hoard labor and under-react to labor demand shocks. The adverse selection problem also creates a market for temporary workers. In equ...

Statement of problem Information on the mechanical properties materials used for manufacturing computer-engineered complete dentures is scarce. Purpose The purpose this in vitro study was to evaluate 3 prepolymerized polymethyl methacrylate (PMMA) resins fabrication computer-aided design and (CAD-CAM) milled (CDs), as well 2 denture base polymers conventionally fabricated CDs. Material methods ...

The generation of hydroxyl radicals and singlet oxygen during the oxidation of 4-(4-hydroxyphenyl)-2-butanol (rhododendrol) and 4-(3,4-dihydroxyphenyl)-2-butanol (rhododendrol-catechol) with mushroom tyrosinase in a phosphate buffer (pH 7.4) was examined as the model for the reactive oxygen species generation via the two rhododendrol compounds in melanocytes. The reaction was performed in the p...

Introduction: Standardization of breast MR image acquisition is not widespread at this time. There are several manufacturers of MR systems, with different k-space sampling methods and coils. Furthermore, dynamic imaging protocols differ across institutions as to timing resolution, use of fat suppression, and pulse sequences. Unlike x-ray mammography, there are no universally applied quality ass...

OBJECTIVE The aim of this study was to evaluate the effects of staining solutions on the color stability and roughness of different provisional resin material. MATERIAL AND METHODS Three different materials were tested (two polymethylmethacrylate and one bis-acryl composite resins) in cola and coffee and for 1 and 4 weeks. 240 specimens were used - half of them polished and other half not. Co...