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A special type of 7 T 240 mm vertical bore cryogen-free superconducting magnet system is developed that can be used for gyrotron. This magnet system has contributed to the fast control of the gyrotron oscillation frequency.

A superconducting magnet of small size and easy operation was developed for generating high magnetic force field. Results suggest the successful operation of the magnet in persistent mode with field decay of less than 1 ppm/h.

A numerical quench simulation code was modified to take into account the impact of filament coupling loss when computing the temperature rise in multisection superconducting coils. The new program, which has been applied to a 17.6-T and a17-T magnet, shows good agreement with experimental results. This is important because the filament coupling loss increases the temperature which, in turn, decreases the critical current in the coil.

A simulation code for worst-case parameter estimation of the quench properties in multisection superconducting coils is introduced. It is a design tool in the joint project between the Massachusetts Institute of Technology and Japan's Kobe Steel Ltd for the development of a 12-coil 17.6-T 750-MHz nuclear magnetic resonance system. Its application for testing the magnet's five outer niobium titanium solenoids are also discussed.

A superconducting magnet generating a magnetic force field of 1500 T(super 2)/ m in a 40 mm diameter room temperature bore is developed. In order to avoid huge axial magnetic forces between the main coils and the reverse coils, the main coils are combined with three sections set asymmetrically.

BACKGROUND: Factors determining renal function at organ recovery in deceased kidney donors are not well established. METHODS: The authors studied the prevalence and risk factors associated with elevated prerecovery creatinine and calculated glomerular filtration rate in 458 deceased organ donors identified through the California Donor Transplant Network between January 2005 and December 2006. Data collected retrospectively included demographics, medical history, laboratory values, mechanism of death, and medical treatment in the intensive care unit. Factors were analyzed by both univariate and multivariate analysis. RESULTS: There were 260 men and 198 women in the study. The age was 43.2 +/- 14.9 yr, and body mass index was 26.9 +/- 6.0 (mean +/- SD). In multivariate analysis, several factors were important determinants of both prerecovery creatinine and glomerular filtration rate. Admission creatinine or glomerular filtration rate were major determinants of respective prerecovery values (P < 0.0001). Higher body mass index was associated with worse renal function (P < 0.01). Higher average glucose values and greater variability in glucose (when included) were associated with worse prerecovery renal function (P < 0.01). Administration of desmopressin acetate was highly associated with preserved renal function (P < 0.001). Lower platelet count (P < 0.0001) and proteinuria (P = 0.005) were also associated with worse renal function. CONCLUSION: The data identify several important factors that predict renal function at kidney recovery in deceased donors. In particular, tighter control of blood glucose may improve renal function in potential organ donors, but prospective studies are needed to confirm these findings. [ABSTRACT FROM AUTHOR]

Today, the number of services, which includes large information contents like high-definition movies, is rapidly increasing. The graded-index plastic optical fiber (GI-POF) has been proposed as a solution. The conventional fabrication method of GI-POF, however, is unsuitable for mass production. Therefore, we propose the dopant diffusion coextrusion process for fabricating high-bandwidth GI-POF. It has been generally thought that formation mechanism of refractive-index distribution in optical polymer materials by this process would be a Fick's diffusion with constant diffusion coefficient and, therefore, has a tailing part at the core-cladding boundary. Contrary to predictions, we succeed in fabricating GI-POF with an almost optimum-index distribution. It is made evident by experiments and simulation that the formation mechanism of GI-POF by this process is a Fick's diffusion with diffusion coefficient dependent on dopant concentration. These results indicate high possibility of fabrication of high-bandwidth fibers of a polymethyl methacrylate-diphenyl sulfide system by the dopant diffusion coextrusion process. [ABSTRACT FROM PUBLISHER]

Cryogen-free superconducting magnets are becoming popular due to their simple operation compared with the conventional liquid Helium cooled magnet. However, for higher fields such as those greater than 14 T, the cryogen-free magnet has not become popular yet, because it is difficult to design and manufacture since the critical current is markedly reduced at higher fields and higher temperatures. We have developed two types of 15 T cryogen-free superconducting magnets, which will be among the highest field magnets in operation as cryogen-free with a GM cryocooler. One magnet has a 52 mm room temperature bore with overall dimensions of 820 mm in diameter and 680 mm in height. This magnet is designed so as to be simple in both operation and installation. Therefore, the magnet is cooled with a single 1 W GM cryocooler. Also, all coils are connected in series and charged with a single power supply. The magnet was successfully charged up to 15 T in 30 minutes and then charged slowly to 16 T without quench. The other magnet has a 170 mm room temperature bore with overall dimensions of 980 mm in diameter and 1015 mm in height. This magnet is designed so as to be used with temperature controlled sample cryostats with an outer diameter of 168 mm. The magnet is cooled with four 1 W GM cryocoolers and charged with a single power supply. The magnet was successfully charged up to 15 T in 90 minutes. Both magnets will enable high magnetic field research or application with very easy operation. [ABSTRACT FROM AUTHOR]

Application of the ion-shadow sputter technique is proposed to produce tips used for the study of point contact as well as for scanning tunneling microscopy (STM). It is a sputtering technique using powders with low sputtering rate as the mask material. By this method, sharp and long tips could be produced for Si, Au, Fe, permalloy and invar. The tip length is typically more than 15 μm, and the radius of curvature is about 10–20 nm or less. Furthermore, a nonmagnetic tip (e.g., Si) capped with a magnetic apex (300 nm Fe) has been produced. This type of tip is clearly useful for STM experiments in transmission electron microscopy (TEM). [Copyright &y& Elsevier]

To investigate the role of oestrogen receptor b (ERβ) in the function of human ovarian corpus luteum, the levels of luteal ERα and ERβ mRNA were determined using competitive reverse transcription–polymerase chain reaction-Southern blot analysis. The expression of ERα and ERβ mRNA was detected in all luteal samples analysed. Luteal ERα and ERβ mRNA levels were significantly lower (P < 0.01 and P < 0.05 respectively) at the late secretory phase than those at the early and mid-secretory phases of the endometrium. The ratio of ERα to ERβ mRNA levels showed no change during the secretory phase of the endometrium. This study demonstrates that ERβ is co-expressed with ERα in human corpus luteum and is likely to play a biological role in the regulation of steroidal action of the corpus luteum with ERα. [ABSTRACT FROM AUTHOR]

To know the potential of growth, invasion and metastasis of uterine cervical cancer associated with neovascularization, localization of vascular endothelial growth factor (VEGF) and microvessel density in tumours were determined by immunohistochemical staining, the levels of VEGF subtypes were determined by Western blot analysis and by a sandwich enzyme immunoassay, and the levels of VEGF subtype mRNAs were determined by reverse transcription polymerase chain reaction (RT-PCR) - Southern blot analysis in uterine cervical cancers. The relation between VEGF subtype expressions and microvessel density, histological types and clinical stages of uterine cervical cancers was analysed. The expression of VEGF was seen dominantly in the cancer cells, and correlated with microvessel density in uterine cervical cancers. Among the four subtypes of VEGF, the populations of VEGF[SUB165] and VEGF[SUB121] were dominant in normal uterine cervices and uterine cervical cancers. The levels of VEGF and VEGF[SUB165] and VEGF[SUB121] mRNAs were remarkably higher in some stage II and III/IV adenocarcinomas of the cervix than in other cases, including normal cervices. Therefore, the elevation of VEGF[SUB165] and VEGF[SUB121] might contribute to the relatively late advancing via angiogenic activity in some adenocarcinomas of the cervix. [ABSTRACT FROM AUTHOR]

Angiogenesis contributes to the growth and secondary spreading of solid tumours. Platelet-derived endothelial cell growth factor (PD-ECGF) is identified as such an angiogenic factor. In the present study, the prognosis of the patients with high PD-ECGF uterine cervical cancers was worse than those with low PD-ECGF cancers, and PD-ECGF expression correlated with cellular proliferation and with vascular density and venous invasion in uterine cervical cancers. Therefore, PD-ECGF might contribute to the growth of uterine cervical cancers via angiogenesis related to vascular spreading. Furthermore, PD-ECGF and its mRNA had a wide range and were highly expressed in uterine cervical cancers, especially squamous cell carcinoma, regardless of clinical stage. Therefore, PD-ECGF in uterine cervical cancers might play a role of basic angiogenesis in all processes of advancing of uterine cervical cancers. This indicates that 5′-deoxy-5-fluorouridine might be highly effective in squamous cell carcinoma of the cervix, which possesses a high activity of thymidine phosphorylase to convert 5′-deoxy-5-fluorouridine to 5-fluorouracil, and that some angiogenic inhibitors of new capillary formation might be effective in the inhibition of tumour growth and spreading associated with angiogenesis. [ABSTRACT FROM AUTHOR]

A 20 T superconducting magnet was designed and developed for studying physical properties. The cryostat is an open neck Dewar vessel with a liquid nitrogen reservoir and radiation shield. A lambda plate is built into the magnet support assembly. The operating temperature can be reduced from 4.2 K to 2.2 K by pumping liquid helium through a throttle valve under the lambda plate. The central magnetic field is 20 T at 2.5 K (18 T at 4.2 K). The field homogeneity is less than +/-0.1% in a 10 mm diameter sphere volume. The inner diameter of the cold clear bore is 52 mm. The outer diameter of the coil is 349 mm. The height of the coil, excluding the magnet protection circuit, is 560.5 mm. The coil is wound with the specially developed wires for use in high magnetic fields. In the case of Nb3Sn wires, a marked increase of the critical current density is achieved with higher tin content in the bronze matrix. The wires arc more resistant to external stress with a rectangular cross section. We hung the magnet into the Dewar vessel and energized it. At first the magnet was operated at liquid helium temperature 4.2 K. As a result, the magnetic field rose to over 18 T with no training quench. The maximum magnetic field was 18.5 T. Then we energized the magnet after reducing the operating temperature to 2.2 K. Finally, the magnetic field rose to over 20 T with no quench. The result of this study shows that this magnet delivers a high magnetic field stably and easily. [ABSTRACT FROM AUTHOR]

Objectives Japanese universities are required to improve both international and Japanese students' mental health, because the number of international students increases annually. Moreover, mental health data for graduate school students in Japan are lacking. Therefore, the present study attempted to examine differences in graduate school students' mental health according to major, grade, and nationality. Methods A total of 587 students from a Japanese university, which only offers graduate school education, completed the Japanese version of Kessler 6 (K6) as part of their regular health assessments; 542 students agreed to the use of their data for research purposes. Results The K6 scores were analyzed using a 3-way (major × grade × nationality) between-subjects ANOVA, and a significant second-order interaction (F(6, 518) = 2.68, p < .05) was observed. As a subsequent 2-way (major × nationality) ANOVA, performed according to grade, only showed an interaction for first-grade master's degree students (M1; F(2, 167) = 7.88, p < .01), comparisons between Japanese and international students were made according to major. For one major, Japanese students' K6 scores tended to be higher relative to those observed in international students (t(36) = 1.98, p < .10). In contrast, international students' K6 scores for another major were significantly higher than were those of Japanese students (t(86) = 3.31, p < .01). Conclusions Japanese and international M1 students' K6 scores differed significantly. University staff should take these differences into account and examine ways to support students. [ABSTRACT FROM AUTHOR]