Electrical probe characteristic recovery by measuring only one time-dependent parameter

Two straightforward methods for recovering the current-voltage characteristic of an electrical probe are proposed. Basically, they consist of replacing the usual power supply from the probe circuit with a capacitor which can be charged or discharged by the probe current drained from the plasma. The experiment requires the registration of only one time-dependent electrical parameter, either the probe current or the probe voltage. The corresponding time-dependence of the second parameter, the probe voltage, or the probe current, respectively, can be calculated using an integral or a differential relation and the current-voltage characteristic of the probe can be obtained.

Serum chromium levels in gestational diabetes mellitus

OBJECTIVE

To measure serum chromium level in women with gestational diabetes mellitus (GDM) from Chennai, South India.

MATERIALS AND METHODS

Thirty women with gestational diabetes, 60 age matched controls.

INCLUSION CRITERIA

Gestational age 22-28 weeks, age group 20-35 years.

EXCLUSION CRITERIA

Gestational age beyond 28 weeks, malnutrition or presence of infection. Serum chromium was measured using inductive couple plasma emission spectrometer.

RESULTS

Serum chromium levels of women with GDM, 1.59+/-0.02 ng/ml (range: 0.16-4.0 ng/ml) were lower than in controls (4.58+/-0.62 ng/ml; range 0.82-5.33 ng/ml) (P < 0.001). However, there were no significant differences among cases and controls when subdivided by parity.

CONCLUSIONS

Women with GDM from a South Indian city had lower levels of serum chromium compared to pregnant women without GDM. Studies may be done whether chromium supplementation is useful in this group of women.