Multi-point density measurement of a collisional merging formation process of FRCs.

Collisional merging formation of field-reversed configuration (FRC) plasmas at supersonic velocities was performed using the FRC amplification via translation-collisional merging device. Supersonic collisional merging formation is a novel technique to form an FRC that is long-lived compared to a conventional initial formation FRC; however, this technique requires measuring the plasma parameters at multiple points simultaneously because of the dynamic translation/merging process. Herein, we have developed a new interferometer and have observed the dynamic behavior of FRCs in the formation, translation, and merging processes simultaneously. In this study, as one of the performance evaluations of the developed simultaneous density measurement, collision/merging of FRCs have been conducted in the confinement section with and without background neutral gas. Comparing translation into deuterium gas vs translation into a vacuum environment prior to the collisional merging, we found that the background neutral particles were trapped in the merged FRC; moreover, a difference in the decay rate of the stored internal energy was observed.

A comparison of patients with premature thelarche and idiopathic true precocious puberty in the initial stage of illness.

A comparative study of patients with premature thelarche and patients with idiopathic true precocious puberty was conducted. The age at the first visit tended to be lower for those with precocious puberty. In comparison with normative data for children, the frequency of low birthweight and small for date (SFD) status was greater in the 55 patients with premature thelarche, but SFD was also frequent in the 18 patients with precocious puberty. The height, weight and Kaup's index were all within the normal range for these two groups. The ratios for bone age/chronologic age and bone age/height age tended to be high in both groups. In the patients with premature thelarche, the blood luteinizing hormone (LH) level showed a normal response, and the blood follicle stimulating hormone (FSH) level a hyper-response, to stimulation with luteinizing hormone-releasing hormone (LH-RH). In contrast, both the blood LH and FSH levels showed a normal response to LH-RH stimulation in most of the patients with precocious puberty, and a hyper-response was rare among them. Although the blood estradiol (E2) level was higher in patients with precocious puberty than in those with premature thelarche, about 50% and 90% of the patients in the respective groups had normal levels. These results suggest that normal responses of blood LH and excessive responses of blood FSH to LH-RH loading may be useful in some patients for diagnosing premature thelarche at an early stage.

Growth hormone neurosecretory dysfunction associated with ring chromosome 18.

The patient was a girl 5 years and 1 month old of markedly short stature (-3.9 SD) for her chronological age. Although her karyotype was 46, XX, r(18)(p11q23), there were no symptoms of a chromosomal deletion. Other authors have described cases with a ring autosome showing a phenotype with short stature alone as 'ring syndrome', regardless of which autosome is involved. The present case seems to fall into this category. Although blood growth hormone (GH) showed normal responses to four types of provocative tests, the mean value of blood GH levels obtained at 30 min intervals for 24 h was low, indicating the existence of growth hormone neurosecretory dysfunction (GHND).