In association with the international validation project to establish an OECD Enhanced Test Guideline 407, we performed a 28-day repeated-dose toxicity study of methoxychlor, a chlorinated hydrocarbon pesticide with pro-estrogenic and anti-androgenic activities. Attention was paid to the sensitivity of certain additional parameters for detecting endocrine related effects of endocrine disrupting chemicals based on the existing TG 407. Seven-week-old Crj:CD(SD)IGS rats were allocated to one of four groups, each consisting often males and ten females, and methoxychlor was administered once daily by gavage at doses of 0 (control), 20, 100 or 500 mg/kg body weight per day. Male rats were killed on the day after the 28th administration. Female rats were killed on the day of the diestrus stage during 4 days after the 28th administration. Male rats receiving methoxychlor showed mainly atrophy of mammary acinus in the 20 mg/ kg and higher groups, together with decreases in prostate and seminal vesicle weights, and atrophy of epididymis, prostate, seminal vesicle and coagulating gland in the 100 and 500 mg/kg groups. In addition, decrease in serum testosterone level, increase in follicle-stimulating hormone level, decrease in testis and epididymis weights, atrophy of semiferous tubules and Leydig cells, decrease in the number of sperm in the caudal epididymis and their motility were observed in the 500 mg/kg group. Female rats receiving methoxychlor showed mainly abnormal estrous cycles, decrease in serum luteinizing hormone level, decrease in ovary weight, proliferation of mammary acinus, atrophy of ovary due to decrease in follicles and corpus luteum in histopathology, hypertrophy of endometrial epithelium of uterus and vagina epithelium in the 100 and 500 mg/kg groups. Among the parameters tested in the present experimental system, effects of methoxychlor on endocrine-related organs were detected with regard to serum hormone, organ weights, histopathological examination in both sexes, estrus cycle in females and sperm examination in males. Based on these results, a no-observed-adverse-effect level (NOAEL) in the present study was estimated to be below 20 mg/kg per day. In particular, the adverse effects were effectively detected in organ weights of accessory sex organs and histopathological examination.

In association with the international validation project to establish an OECD Enhanced Test Guideline 407, we performed a 28-day repeated-dose toxicity study of genistein, which is known as a phytoestrogen. Attention was paid to the sensitivity of certain additional parameters, such as histopathology observations and organ weights of endocrine related organs, sperm characteristics, serum hormone levels and estrous cycle, for detecting endocrine-related effects of endocrine-disrupting chemicals based on the existing TG 407. Seven-week-old Crj:CD(SD)IGS rats were assigned to one of four groups, each consisting of ten males and ten females, and genistein was administered once daily by gavage at doses of 0 (control), 120, 400 or 1000 mg/kg body weight per day. Male rats were killed on the day after the 28th administration. Female rats were killed on the day of the diestrus stage during the 4 days after the 28th administration. Endocrine-disrupting effects of genistein were detected in females by histopathology. The changes included vacuolation and mucinification of the vaginal epithelium in the 400 and 1000 mg/kg groups; however, the incidences of the lesion were very low. Although increased serum prolactin levels were recorded in the males of the 1000 mg/kg group, we could not determine whether this was indeed induced by genistein. General toxicological effects of genistein were detected in blood chemistry, such as increased triglycerides and total protein and a decreased albumin/globulin ratio, as well as increased liver weight and glycogen deposition in the periportal hepatocytes. Based on these results, the no-observed-adverse-effect level (NOAEL) in the present study was estimated to be 120 mg/kg per day. In particular, endocrine-related effects were most sensitively detected by histopathology examination of sexual organs. However, the findings indicate that chemicals with weak endocrine-disrupting potential like genistein must be evaluated taking into consideration the results of other test systems.

We developed an axial gap permanent magnet type high temperature superconducting synchronous motor (PMHTSSM) at liquid nitrogen temperature. There are two distinctive differences between this motor and the conventional HTS motors. The permanent magnet is applied to the field, iron cores and HTS wires are used as the armature. The motor has eight field poles, and six armature windings. The armature is put between the two fields. The field composes eight permanent magnets which are arranged as a circle. Four poles share three armature coils and there are two coils for every phase. The BSCCO wires, which are applied to armature windings, work at the temperatures of between 66 K and 70 K. The rated output is 400 kW at 250 rpm. It is known that superconducting wires have AC loss if they are operated at alternating magnetic fields. That is why there are few motors developed with superconducting armature windings. Also, there is no report of motors applying HTS wires such as BSCCO wires to armature windings. Furthermore, this motor adopted the revolving field type structure, so the brushes were not needed and the cooling system can be fixed. Also because of the axial-flux type, the structure of the cryostat can be simplified. Index Terms-Axial flux type, BSCCO HTS wire, permanent magnet, permanent magnet HTS synchronous motor. I. INTRODUCTION W E developed a liquid nitrogen cooled axial flux type Permanent Magnet High Temperature Superconducting Synchronous Motor (PMHTSSM). In order to pursuit a high efficiency and small size HTSM and PM synchronous machine, this motor used liquid nitrogen temperature HTS wires as the armature windings instead of copper wires. Since the permanent magnets are used in the field, the armature iron core is necessary to obtain large magnetic flux density.

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