Reduction In Number Of Trials Research Articles

Self-microemulsifying drug delivery system (SMEDDS) of curcumin attenuates depression in olfactory bulbectomized rats

BackgroundCurrent therapies for depression remain limited and plagued by various side effects. Problems associated with curcumin administration include poor aqueous solubility and bioavailability issues. Hence to overcome these, curcumin self micro emulsifying drug delivery system (SMEDDS) which will result in a nanosize emulsion droplets when administered in vivo were formulated in the present study. MethodsDepression was induced by bilateral olfactory bulbectomy and the animals were randomized into 8 groups as normal, control [(vehicle 10 ml/kg, p.o., (per oral)], pure curcumin (10, 20, 40 mg/kg, p.o.), and curcumin SMEDDS (10, 20, 40 mg/kg, p.o). After 14 days of respective treatment, behavioral parameters such as open field test (OFT), ambulation counts and passive avoidance response (PAR) were evaluated. At the end of experiments, blood was withdrawn from r.o.p (retro orbital plexus) for serum cortisol estimation. ResultsIn OFT, increased central area frequency, peripheral area frequency, central area duration and decreased rearing and grooming were recorded with an increased ambulation counts. In PAR, significant reduction in number of trials and step down from platform was observed in the animals treated with test drug. Serum cortisol level was also found to be decreased in the test groups. ConclusionBehavioral and biochemical estimations in the present study revealed the improved brain permeability and further increase in biological activity of curcumin SMEDDS.

Application of Taguchi's Design of Experiments to the Study of Biomechanical Systems

An efficient global optimization procedure is presented by using Taguchi's design of experiments (TDE) as a means for undertaking biomechanical studies that rely on experimentations. The proposed TDE is a systematic method of fractional factorial designs for conducting experiments with many independent variables. The approach can provide a step-by-step means for predicting the results of a comparative full factorial design only with a small number of tests. In this study a three-level, four-variable heel-toe running model, and a two-level, seven-variable bicycle example were examined to show the capability and robustness of TDE. In the process of the analysis, the orthogonal array and signal-to-noise ratio analysis of TDE were used to set up the trial conditions and analyze the results. It is shown that in the heel-toe running analyses the TDE successfully predicted the optimum sets of variables with 89% fewer trials than the full factorial design. The reduction in number of trials in the bicycle example is 94%. As a result, the use of TDE analysis to replace a full factorial analysis can considerably reduce the number of trials and still provide a useful outcome in many multifactor biomechanical studies.

Facilitation of heartbeat self-detection in a choice task

Brener and Kluvitse (Psychophysiology 25 (1988) 554) developed a heartbeat self-detection task in which subjects are required to judge the simultaneity of heartbeat sensations and tones presented at six intervals following the onset of each ventricular contraction (0, 100, 200, 300, 400 or 500 ms). They found that most of their participants considered as simultaneous in the intervals of 100, 200 and 300 ms, in comparison to those of 0, 400 and 500 ms. In the research reported here, an adaptation of this task was administered to 32 subjects (16 men, 16 women) to see whether these interval choices would be replicated using a narrower range of values, and if task performance would be affected by the reduction in number of trials from 30 to 20. The interval values of the external stimuli with reference to the R-wave were 150, 200, 250, 300 and 350 ms. The results indicate that there was a clear choice for the intervals of 150 and 200 ms in comparison to the rest and that the performance of participants decreases after 20 trials.