Equivalent magnetic vector potential model for low-frequency magnetic exposure assessment.

In this paper, a novel source model based on a magnetic vector potential for the assessment of induced electric field strength in a human body exposed to the low-frequency (LF) magnetic field of an electrical appliance is presented. The construction of the vector potential model requires only a single-component magnetic field to be measured close to the appliance under test, hence relieving considerable practical measurement effort-the radial basis functions (RBFs) are adopted for the interpolation of discrete measurements; the magnetic vector potential model can then be directly constructed by summing a set of simple algebraic functions of RBF parameters. The vector potentials are then incorporated into numerical calculations as the equivalent source for evaluations of the induced electric field in the human body model. The accuracy and effectiveness of the proposed model are demonstrated by comparing the induced electric field in a human model to that of the full-wave simulation. This study presents a simple and effective approach for modelling the LF magnetic source. The result of this study could simplify the compliance test procedure for assessing an electrical appliance regarding LF magnetic exposure.

Effect of an antidiabetic polysaccharide from Inula japonica on constipation in normal and two models of experimental constipated mice.

OBJECTIVES: The aim of the present study was to investigate the effect of an antidiabetic polysaccharide (IJP) from Inula japonica on gastrointestinal transit in normal mice and on constipation in two models of constipated mice. METHODS: Two models of constipation in mice were respectively induced by fasted water for 4 days or induced by diphenoxylate. The normal and constipated mice were administered IJP once at doses of 100 and 400 mg/kg (p.o.), the gastrointestinal vermicular motion, start time of defecation, number and weight of stool were investigated. RESULTS: After administration of IJP, the gastrointestinal propulsive rate was increased by 9.79% and 10.42%, the start time of defecation was shortened by 37.27% and 44.06%, the number of feces increased by 115.4% and 130.8% in normal mice. In fasting-water constipated mice, the start time of defecation was shortened by 9.69% and 30.52% by IJP, defecation granules raised by 22.09% and 39.53%, wet feces weights were increased by 23.50% and 39.14% compared with the untreated constipated mice. In diphenoxylate-induced mice, the start time of defecation was shortened by 25.48% and 28.13%, defecation granules raised by 100.0% and 118.0%. CONCLUSIONS: Consumption of IJP effectively improved bowel movement, stool output observed in this study. IJP may be practical in relieving constipation in the elderly diabetic population.