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A prototype tokamak poloidal field coil of 3 m diameter was successfully tested. The coil was designed to withstand typical field transients like fast ramping, plasma controlling and plasma disruptions. In order to achieve these requirements a low loss conductor was developed. The coil with its components was designed according to rules of high voltage technology. A realistic test of the magnet requires at 23 kV a current of 15 kA, that means a peak power of 345 MW. Therefore, a fast switching circuit was used combined with an additional current lead at the middle of the magnet winding. This allowed the performance of fast field changes with increasing or decreasing field. In one operation mode the coil was discharged into a dump resistor. In another operation mode, only one coil half is discharged which generated a field increase in the second short circuited half of the coil. Discharging time constants of 1 ms and local field sweep rates of about 240 T/s were obtained without quench. A reproducible and sharp quench boundary was found. The results showed clearly that ramp rate limitations are only given by the expected stability limit or the load line boundary.

A 30 kA/23 kV current lead cooled by forced-flow supercritical helium has been developed at KfK. It allows position independent installation and well controlled operation which would be advantageous for operation of all kind of super-conducting forced-flow cooled magnets. The design of the lead is described in this paper. The main feature is the insertion of [Nb.sub.3]Sn wires inside the conductor of the heat exchanger allowing the operation at minimum mass flow in a wide current range. Measurement results are presented for steady-state operation up to 30 kA, for short time operation up to 50 kA, for pulsed operation up to [+ or -] 1000 A at 10 Hz, and for simulation of loss of mass flow. A high-voltage test up to 28 kV DC has been done. The mass flow rate normalized to current is about 0.055 g/(s-kA) for 15 to 30 kA proving the effectiveness of the [Nb.sub.3]Sn inserts. Comparison to numerical calculations shows good agreement allowing extrapolation for the design of leads for currents up to 80 kA for ITER model coil tests in the TOSKA test facility at KfK.

At Alma-Ata in 1978, WHO and UNICEF together endorsed the policy of community-oriented primary health care (COPC) (1). However, the ideas girding and framing this approach had first been given [...]

Objective: To test a priori hypotheses that miscarrying women are at increased risk for a first or recurrent episode of major depressive disorder in the 6 months following loss and that this increased risk is greater for childless women, women with prior reproductive loss, and women aged 35 years or older; and to evaluate whether risk varies by time of gestation or by attitude toward the pregnancy.Design: Cohort study.Setting: The miscarriage cohort consisted of women attending a medical center for a spontaneous abortion (n=229); the comparison group was a population-based cohort of women drawn from the community (n=230).Participants: Miscarriage was defined as the involuntary termination of a nonviable intrauterine pregnancy before 28 completed weeks of gestation. Half of all participants were between 25 and 34 years of age; 40% were white and 35% Hispanic; 55% had more than a high school education. Participants constituted 60% of miscarrying women and 72% of community women who completed the first phase of this cohort study.Main Outcome Measure: Major depressive disorder was measured using the Diagnostic Interview Schedule.Results: Risk for an episode of major depressive disorder among miscarrying women in the 6 months following loss was compared with the 6-month risk among community women who had not been pregnant in the preceding year. Among miscarrying women, 10.9% experienced an episode of major depressive disorder, compared with 4.3% of community women. The overall relative risk (RR) for an episode of major depressive disorder for miscarrying women was 2.5 (95% confidence interval [CI], 1.2-5.1) and was substantially higher for childless women (RR, 5.0; 95% CI, 1.7-14.4) than for women with children (RR, 1.3; 95% CI, 0.5-3.5) (P<.06). Among miscarrying women, 72% of cases of major depressive disorder began within the first month after loss; only 20% of community cases started during the comparable period. Among miscarrying women with a history of major depressive disorder, 54% experienced a recurrence. However, RR did not vary significantly by history of prior reproductive loss or by maternal age, nor did risk vary by time of gestation or attitude toward the pregnancy.Conclusions: Physicians should monitor miscarrying women in the first weeks after reproductive loss, particularly women who are childless or who have a history of major depressive disorder. Where appropriate, supportive counseling or psychopharmacologic treatment should be considered. [ABSTRACT FROM AUTHOR]