Partial discharge characteristics of inverter-fed motor coil samples under ac and surge voltage conditions

This work investigates the partial discharge (PD) characteristics of twisted pair samples for inverter-fed motor coil under ac and surge voltage conditions. It also discusses the difference in the PD inception characteristics of a twisted pair under 60-Hz voltage and surge voltages with a steep wave front. The PDIV under ac voltage was measured and was found to agree well with the theoretical value using electric field analysis and Paschen's law. The PDIV under surge voltage was measured for different repetition rates and the PDIV for 60-pps repetition was found to be lower than those for 6 pps and for the single shot, which suggested that the electrical insulation performance would be influenced by the repetition rate. The PDIV under surge voltages was 1.5 to 1.8 and 2.3 to 2.7 times higher than those under AC voltage application for the used and virgin samples, respectively.     

Superconducting digital electronics

Single-flux quantum logic (SFQ) circuits, in which a flux quantum is used as an information carrier, have the possibility for opening the door to a new digital system operated at over 100-GHz clock frequency at extremely low power dissipation. The SFQ logic system is a so-called pulse logic, which is completely different from the level logic for semiconductors like CMOS, so circuit design technologies for SFQ logic circuits have to be newly developed. Recently, much progress in basic technologies for designing SFQ circuits and operating circuits at high speeds has been made. With advances in these design tools, large-scale circuits including more than several thousand junctions can be easily operated with the clock frequency of more than several tens of gigahertz. High-end routers and high-end computers are possible applications of SFQ logic circuits because of their high throughput nature and the low power dissipation of SFQ logic. In this paper, recent advances of SFQ circuit design technologies and recent developments of switches for high-end routers and microprocessors for high-end computers that are considered possible applications for SFQ logic will be described.     

Preliminary results of fine needle aspiration biopsy histology in upper gastrointestinal submucosal tumors

To elucidate the characteristics of lung cancer complicated by pneumoconiosis, we compared the clinical features of complicated and uncomplicated lung cancer cases. The average age at onset was higher for patients with pneumoconiosis than for those without. Because pneumoconiosis presents various respiratory symptoms, subjective symptoms were less important than objective symptoms in detecting lung cancer complicated by pneumoconiosis. Although fiberoptic bronchoscopy was the predominant diagnostic method, it could not be used with the pneumoconiosis patients. Diagnoses of lung cancer complicated by pneumoconiosis were made more after by percutaneous needle aspiration cytology. Squamous cell carcinoma is the most frequent form of cancer in patients with pneumoconiosis, which suggests that the inhalation of carcinogens may play a role in the pathogenesis of lung cancer. With respect to the smoking index (SI), histological specimens indicated that the incidence of squamous cell carcinoma in patients with pneumoconiosis was significantly higher in heavy smokers (SI > or = 600) than in light smokers (SI < 600) or nonsmokers. It is suspected that smoking affects carcinogenesis of pneumoconiosis. No differences in the distribution of lung cancer (right-left, hilar-peripheral) distinguished the 2 groups. Many of the patients with peripheral-type lung cancer and pneumoconiosis had tumors in the lower lung lobes. These findings underline the importance of encouraging pneumoconiosis patients to avoid lung cancer by not smoking, and to have lung cancer detected in its early stages by undergoing regular medical exams.     

Measurement of erosion yields for a SiC surface on H+, D+ and Ar+ bombardment

Changes in the distribution of silicon solute in a 99.8% pure nickel crystal after 75 keV Ni⁺ ion bombardment at 16°C and 500°C, are reported. The concentration depth profiles were measured by simultaneous sputter-profiling and secondary ion mass spectrometry (SIMS). At 16°C the results are satisfactorily explained by the formation and subsequent migration to sinks of nickel interstitial-silicon complexes. The same mechanisms can be used to explain the results obtained at 500°C but the effect observed could also be due to the migration of vacancy-silicon complexes to sinks and the possibility that both mechanisms occur simultaneously cannot be ruled out.     

Acute exacerbation following bronchoalveolar lavage in idiopathic interstitial pneumonia

We report two cases of idiopathic interstitial pneumonia (IIP) with acute deterioration after bronchoalveolar lavage (BAL). Case 1 was a 54-year-old woman, and case 2 was a 75-year-old man. Both were diagnosed as having IIP, and hospitalized with complaints of high fever and dyspnea. After BAL, the degree of dyspnea increased. White blood cell count and lactate dehydrogenase were elevated, and PaO2 was decreased. Chest X-ray revealed consolidation of the upper lung fields and reticulo-granular shadows spreading through both lungs. BAL fluid examination showed an elevated neutrophil fraction (case 1: 6.5%, case 2: 35.2%), suggesting respiratory tract infection although bacteria could not be detected. Case 1 died of respiratory failure despite corticosteroid therapy. Autopsy revealed diffuse alveolar damage with focal pneumonia in the right S6 corresponding to the upper lobe consolidation. Case 2 improved after antibiotic therapy. These findings suggest that aspiration of infected fluid during BAL can cause acute exacerbation of IIP. It is important to recognize that the BAL procedure can induce an acute exacerbation of IIP.     

Vitamin E and coenzyme Q concentrations in the thyroid tissues of patients with various thyroid disorders

Chylous fistula complicates 1.1% of all radical neck dissections, and 2.4% of left-sided dissections. The standard treatment of established chylous leak in the reported cases is a pressure dressing applied to the lower neck. Here we present a case of chylous fistula, where conservative methods failed to cope with this complication. The additional application of a fibrin adhesive set was a successful modality of treatment.     

Scientific rationale for the replacement of an in vivo bioassay for protein drugs with a physico-chemical assay

Recent progress in both protein drug production technologies including biotechnology and protein characterization methodologies has enabled us to mass-produce and extensively characterize highly purified protein drugs. The quality control of these protein drugs, being based on such a background, should be carried out using various modern protein analytical methodologies. One of the points to be considered regarding control strategies for these protein drugs should be the development and standardization of more specific, precise, simple and economical assay methodology. The replacement of existing in vivo bioassays with certain in vitro assays, including physico-chemical assays, is one possible directions along this line. This paper describes strategies for the replacement of an in vivo bioassay for protein drugs with a physico-chemical assay. Such approaches have been applied for recombinant human growth hormone and recombinant human insulin, the potencies of which have been estimated by in vivo bioassay. Scientific rationale for such approaches are also discussed.