presence of available and stable fluoride in a dentifrice formulation is a major requirement for an anti-caries effect. although the available fluoride concentration in iranian dentifrices has been reported in previous studies, there is little information on its stability; which is dependent upon dentifrice formulation. this study was done to assess the fluoride ion concentration and stability ...

background: although various surface disinfectants have been introduced, most of them are toxic. the use of natural antimicrobial agent e.g. phytol, extracted from leptadenia pyrotechnica is a new strategy. the aim of this study was to evaluate the antimicrobial activity, toxicity, and stability of phytol. methods: the serial concentrations of phytol were prepared, and separately incubated with...

in this paper, a new t-s fuzzy hyperbolic delay model for a class of nonlinear systems with time-varying delay, is presented to address the problems of stability analysis and feedback control. fuzzy controller is designed based on the parallel distributed compensation (pdc), and with a new lyapunov function, delay dependent asymptotic stability conditions of the closed-loop system are derived v...

In this paper, we consider the stability and robust stability for descriptor systems with time-varying delay. First, we attempt to obtain delay-dependent stability conditions via linear matrix inequalities (LMIs). In the derivation of delay-dependent stability conditions, we define an appropriate Lyapunov-Krasovskii functional and use a free weighting matrix method and Jensen’s inequality, whic...

the aim of this investigation was to prepare, characterize and optimize the aceclofenac proniosomes using central composite design and carry out stability studies. three independent variables selected were molar ratio of drug to lipid (x1), surfactant loading (x2) and volume of hydration (x3). based on central composite design, 16 batches of proniosomes were prepared by slurry method and evalua...