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Notes: On warming the previously white light illuminated yttrium iron garnet with some deficiency of oxygen with a white light, an imaginary part of permeability μ‘ below 10 kHz has been found to show the triple peaks as a function of temperature, the activation energies of which are 0.095–0.22, 0.50, and 0.81 eV, respectively. Furthermore, the height of each peak depends strongly on the illuminating time of exciting light. These features have been discussed and interpreted based on a modified "two-center'' model.

Notes: The construction and the fundamental studies of a repetitive flash x-ray generator having a simple diode with an energy-selective function are described. This generator consisted of the following components: a constant high-voltage power supply, a high-voltage pulser, a repetitive high-energy impulse switching system, a turbo molecular pump, and a flash x-ray tube. The circuit of this pulser employed a modified two-stage surge Marx generator with a capacity during main discharge of 425pF. The x-ray tube was of the demountable-diode type which was connected to the turbo molecular pump and consisted of the following major devices: a rod-shaped anode tip made of tungsten, a disk cathode made of graphite, an aluminum filter, and a tube body made of glass. Two condensers inside of the pulser were charged from 40 to 60 kV, and the output voltage was about 1.9 times the charging voltage. The peak tube voltage was primarily determined by the anode-cathode (A-C) space, and the peak tube current was less than 0.6 kA. The peak tube voltage slightly increased when the charging voltage was increased, but the amount of change rate was small. Thus, the maximum photon energy could be easily controlled by varying the A-C space. The pulse width ranged from 40 to 100 ns, and the x-ray intensity was less than 1.0 μC/kg at 0.3 m per pulse. The repetitive frequency was less than 50 Hz, and the effective focal spot size was determined by the diameter of the anode tip and ranged from 0.5 to 3.0 mm in diameter.

Notes: The combined utilization of directly characterized off-plane circularly polarized synchrotron radiation and an ultrahigh-vacuum compatible superconducting magnet has enabled magnetic-circular-dichroism (MCD) experiments, mainly at the M2,3 core absorption edges. Details concerning the experimental technique, which allowed quantitative MCD measurements, are described. The results are presented and discussed for single crystals of Ni, Fe, and Fe3O4, and an Fe/Pt multilayer.

Notes: The construction and the fundamental studies of a kilohertz-range flash x-ray generator having a triode in conjunction with an extremely hot cathode are described. This generator consisted of the following components: a constant-high voltage power supply, an energy storage condenser of 100 nF, a constant high-voltage power supply for regulating an initial grid voltage of −1.6 kV, a grid pulser, and an x-ray tube. The x-ray tube was of an enclosed-triode type and consisted of the following major parts: an anode rod made of copper, a plane anode tip (target) made of tungsten, a focusing electrode made of iron, a hot cathode (filament) made of tungsten, a grid made from tungsten wire, and a glass tube body. The energy storage condenser was charged from 50 to 70 kV, and the electric charges in the condenser were discharged repetitively to the x-ray tube by the grid electrode driven by the grid pulser. The temperature of the filament was about 2000 K, and the cathode current was primarily controlled by the grid voltage and its value was less than 1.2 A. The pulse widths were about 1 μs and the maximum repetitive frequency was about 2.0 kHz. The x-ray intensity was 19.7 nC/kg at 0.5 m per pulse with a peak grid voltage of 1.0 kV and a condenser charged voltage of 70 kV.

Notes: X-ray topography using extremely asymmetric diffraction under the specular reflection condition is effective for imaging a short-range strain field near the surface. This experimental condition is easily realized by utilizing the tunability of synchrotron radiation. The surface defect images are clearly observed as a result of the reduction of background due to dynamical diffraction from the highly perfect bulk crystal.

Notes: Paraneoplastic pemphigus, a recently identified disease entity, is associated with autoantibodies against a variety of epidermal proteins including desmoplakins I and II, and the 230-kDa bullous pemphigoid (BP) antigen. We report an 84-year-old Japanese man who had typical clinical and histopathological features of BP, but in whom indirect immunofluorescence, using normal human skin as the substrate, revealed concomitant serum antibasement membrane zone and antikeratinocyte cell surface autoantibodies. His serum showed reactivity similar to that which is seen with antidesmoplakin monoclonal antibody on immunofluorescence of cardiac muscle and urinary bladder. With immunoblotting, using various antigen sources, the patient's serum reacted with desmoplakins I and II. and with both the 230- and 180-kDa BP antigens. Immunogold electron microscopy also indicated the presence of antidesmoplakin antibodies. Although the significance of the antidesmoplakin antibodies in this patient is unknown, the findings in this case may provide an insight into understanding the occurrence of antidesmoplakin antibodies in paraneoplastic pemphigus.

Notes: Three cases of trichilemmal keratosis (horn) were light microscopically examined and all showed numbers of U- or V-shaped epidermal proliferations which keratinized in a fashion either identical or similar to trichilemmal keratinization. Electron microscopy revealed both uneven and linear borders between the keratinized and the keratinizing cells with a few keratohyalin droplets, remnants of desmosomes, no marginal band in the horny layer, perinuclear vacuolation, few spherical bodies in the intercellular spaces (ICS) of the upper epidermis, and widening of the ICS of the lower epidermis. A number of electron dense spherical particles. 40-50 nm in diameter, were observed in nuclei of the upper epidermis. This suggests that ultrastructure of trichilemmal keratosis is similar rather to viral warts than to trichilemmal cysts, although there are close similarities between trichilemmal keratosis and cyst.

Notes: A tumor of 60 years' duration overlying the sternum of an 87-year-old woman is described. Histologically, the tumor was composed of lobules and cords of epithelial cells with finely granular, eosinophilic cytoplasm. The epithelial nests were floating in large pools of mucinous stroma, separated by thin fibro-vascular septa. Cytoplasmic argyrophilia was seen by Grimelius silver stain. Positive reactions of the tumor cells were also found for chromogranin and neuron-specific enolase. Ultrastructural study revealed that the cytoplasm of the tumor cells contained two types of granules: neurosecretory and mucinous. From these findings, the present tumor is considered to be a carcinoid tumor with amphicrine cells, and the term ‘mucinous carcinoid’ of the skin seems to be appropriate for the diagnosis of the present case.

Notes: The recognition that destructive periodontal diseases may be caused by specific microorganisms in periodontal pockets has led to an increased interest in and usage of antimicrobial agents in periodontal therapy. Recently, a new controlledrelease insert containing ofloxacin, a synthetic antibiotic, has been developed. In this study, the controlled-release insert (PT-01) was microbiologically evaluated in combination with or without subgingival mechanical debridement. PT-01 was applied in the periodontal pockets of 27 patients with chronic periodontitis. Three sites with a deep probing pocket depth (≥5 mm) were randomly selected in different quadrants of each patient, and were assigned into three groups, i.e., PT01 applied (T), placebo applied (P) and control sites (C). Periodontal treatments consisted of supragingival scaling with oral hygiene instruction for the first 2 weeks followed by root planing and subgingival scaling. PT-01 was applied weekly on day 0 to 35, and the subgingival plaque samples from each site were collected on d 0, 14, 21 and 42. The dynamics of the subgingival microflora was investigated by dark field microscopy and by anaerobic and aerobic cultivation. In the supragingival scaling period, significant reduction in percentages of spirochetes and motile rods and significant increase of the percentage of coccoid cells were observed only at T sites. In addition, the total viable counts of bacteria, black-pigmented Bacteroides and Fusobacterium species were significantly reduced at T sites. After mechanical subgingival debridement, significant shifts in the proportion and reduction of the viable counts in the subgingival microflora were found at all sites. Although PT-01 applied sites showed some further shift in the proportion and reduction in subgingival microorganisms, statistically no significant differences in the microbiological results between the three groups of experimental sites were found. These results suggested that weekly application of PT-01 in the periodontal pocket could have significant effects on both qualitative and quantitative changes in the subgingival microflora. However, the mechanical subgingival debridement, consisting of root planing and subgingival scaling, was very effective in eliminating the subgingival microflora by itself. Then, in the combination with mechanical subgingival debridement, statistically no additional effects could be found. Consequently, it was suggested that the application of PT-01 might have an ameliorating effect as an adjunct in conventional periodontal therapy.