ABSTRACT
A highly sensitive optical fiber Fabry-Perot interferometer (FPI) for strain measurement with temperature compensation is proposed. Instead of using another actual reference interferometer, a virtual FPI is constructed to superpose with the sensing FPI to form the Vernier effect. The fundamental and the first-order harmonic Vernier effect are generated to increase the sensitivity by adjusting the parameter of the virtual FPI. In order to separate the strain from the environment temperature, an FBG is cascaded to distinguish the applied temperature. Experimental results demonstrate that, with the help of the fundamental Vernier effect, the sensitivity and temperature of the FPI increases from 1.05 pm/°C to 10.63 pm/°C in the temperature range of 40-120°C, and the sensitivity of strain increases from 2.635 pm/µÎµ to 33.11 pm/µÎµ in the strain range of 0-400 µÎµ. In order to access the tracking points more easily and further enhance the sensitivities, the first-order harmonic Vernier effect is generated by modifying the virtual FPI. Results show that the temperature and strain sensitivities are 21.25 pm/°C and 62.25 pm/µÎµ, respectively. In addition, with the help of the FBG, the strain can be separated from the temperature by solving the cross-sensitivity matrix.
ABSTRACT
OBJECTIVE To study the pharmacodynamics and pharmacokinetics of domestic fixed-dose of antituberculosis drugs and to evaluate its quality and activity against Mycobacterium tuberculosis both in vitro and in vivo. METHODS The MIC was determined by the tube doubling dilution method, and the effect of the drugs was assessed by half survival time of the mice. A single oral dose of domestic and imported fixed-dose combination of antituberculosis drugs was given to healthy volunteers, and the drug concentration in serum was determined by HPLC. The pharmacokinetic parameters and the relative bioavailability were calculated. RESULTS The MIC of each composition in the compound (INH, RFP, PZA) against Mycobacterium tuberculosis was lower than that of each composition used by single-dose. In a murine tuberculosis model, the antituberculosis activity of this compound drug was superior to that of each agent used alone with the same dose. No significant difference was found as compared to the imported drug, Refater; The major pharmacokinetic parameters of the domestic and the imported drugs, t (1/2), C (max), AUC, and t(max), were not significantly different. Statistical analysis showed the two formulations were bioequivalent. CONCLUSION The three compositions in the combination had synergistic effect, and the domestic and the imported drugs were bioequivalent.