Pressure-induced valence anomaly in TmTe probed by resonant inelastic X-ray scattering.

The pressure-induced valence transition in TmTe was investigated by resonant inelastic x-ray scattering at the Tm L3 edge, a powerful probe of the rare-earth valent state. The data are analyzed within the Anderson impurity model which yields key parameters such as the Tm 4f-5d hybridization. In addition to the general tendency of the f electrons towards delocalization, we find a plateau in both the Tm valence and hybridization pressure dependences between 4.3 and 6.5 GPa which is interpreted in terms of an n-channel Kondo (NCK) screening process. This behavior is at odds with the usually continuous, single-channel Kondo-like f delocalization while being supported by the seminal calculations of the NCK temperature in Tm ion by Saso et al. Our study raises the interesting possibility that an NCK effect realized in a compressed mixed-valent f system could impede the concomitant electron delocalization.

Ordering of hydrogen bonds in high-pressure low-temperature H2O.

The near K-edge structure of oxygen in liquid water and ices III, II, and IX at 0.25 GPa and several low temperatures down to 4 K has been studied using inelastic x-ray scattering at 9884.7 eV with a total energy resolution of 305 and 175 meV. A marked decrease of the preedge intensity from the liquid phase and ice III to ices II and IX is attributed to ordering of the hydrogen bonds in the proton-ordered lattice of the latter phases. Density functional theory calculations including the influence of the Madelung potential of the ice IX crystal correctly account for the remaining preedge feature. Furthermore, we obtain spectroscopic evidence suggesting a possible new phase of ice at temperatures between 4 and 50 K.

Ultrastructural features of penile tissue in impotent men.

Penile erection is related to the integrity of penile tissue. In order to study the ultrastructural histopathological changes in penile erectile tissue in impotent men, biopsies were taken from 29 impotent and 5 normal patients during surgical treatment. Light microscopy revealed insignificant histological changes and various degrees of fibrotic change in the corpora cavernosa of impotent men, and electron microscopy revealed severe myopathic, fibrotic changes in the penile tissue. These non-specific changes could not be used to determine the aetiology of impotence, and the relationship between the ultrastructural appearances, the causes of impotence and the results of treatment was unclear. Further studies are required to establish the value of intracorporeal biopsy in selecting treatment for impotent patients.

[Effects of PGE1 on penile blood flow].

From February to July in 1989, 47 patients came to our O.P.D. with the chief complaint of impotence. The average age was 48.3 +/- 10.7 y/o. We applied intracoporeal injection of prostaglandin PGE1 (20 mg); and evaluated its penile blood flow effect by color duplex scanning (Acuson 128). The erectile responses of the test showed that: 6 patients (12.8%) had normal response: and 16 patients (34%) had imperfect response. Altogether, the total positive response rate was 46.8%, and 25 patients (53.2%) showed impaired response. The onset of response was 9.1 +/- 3.6 minutes and the duration of erection was 59.2 +/- 24.7 minutes. The percentage of diameter change of both deep arteries after injection was Rt: 58.1 +/- 41.5%; left: 52.3 +/- 35.6%. The peak velocity of right cavernosal arterial flow after intracoporeal injection was 35.5 +/- 15.9 cm/sec; and that of the left side was 33.2 +/- 16.9 cm/sec. There was no correlation between the increment of peak velocity of the deep arterial flow and the erection grade. The same phenomenon was also found between the increased change in the diameter of the deep artery and the erection grade. 16 patients (34.1%) experienced tolerable pain during the procedure. Two patients (4.3%) experienced dizzines and discomfort due to venous leakage. No priapism was found. This study suggests PGE1 may be an excellent potential alternative to other vasoactive drug with less complication in the diagnosis and treatment of impotence. But the cost and stability were its shortcoming.(ABSTRACT TRUNCATED AT 250 WORDS)