Effect of inner diameter on friction torque in the friction welding of pipes

To clarify the joining mechanism of friction welding, the authors have previously investigated joining phenomena in the first phase of friction welding using solid round bars.^1-5 The results obtained in these studies have led to the proposal of a method for simulation of friction torque in the first phase of friction welding with the friction welding conditions and the physical values of the base metals adopted as key parameters of interest. Results have also led to the development of a method for simple estimation of the initial torque based on the base metal yield strength at the seizure temperature of the faying surfaces.⁶     

Prediction method of unburnt carbon for coal fired utility boilerusing image processing technique of combustion flame

A method for predicting unburnt carbon in a coal-fired utility boiler has been developed using an image processing technique. The method consists of an image processing unit and a furnace model unit. The temperature distribution of combustion flames can be obtained through the former unit. The latter calculates dynamics of the carbon reduction from the burner stages to the furnace outlet using coal feed rate, air flow rate, and the chemical and ash content of the coal. An experimental study in the Sendai Power Station of Tohoku Electric Company Inc. shows that the prediction error of the unburnt carbon can be reduced to 10%. The results show that the unburnt carbon prediction algorithm could be widely used for evaluation, optimization and diagnosis of combustion systems for various boiler and coal types     

Heterogeneity of DNA ploidy pattern in carcinoma of the gallbladder: primary and metastatic sites

There are few detailed reports on the heterogeneity of the nuclear DNA ploidy pattern in carcinoma of the gallbladder. We studied twelve autopsied cases who died of extended gallbladder carcinoma. Multiple samples were taken from the primary site (Pri), from direct invasion of the liver (Hinf), from hematogenous metastasis to the liver (H), from lymphatic metastasis (LN) and from peritoneal dissemination (P). The DNA ploidy pattern was investigated by image cytometry. Heterogeneity of the DNA ploidy pattern in Pri, Hinf, H, LN and P was found in 7/11, 2/10, 5/10, 2/6 and 3/6 cases, respectively. Aneuploidy was more frequently found in Hinf than at the Pri. The DNA index of Hinf was significantly higher than that of Pri. Several stemlines, with different quantities of DNA, were found in Pri. Most of these stemlines were also observed in other sites. These facts may suggest that polyclonal cancer cells rather than one cancer cell or monoclonal cancer cells of a Pri metastasize or infiltrate, and that various polyclonal cancer cells proliferate to different degrees under different circumstances.     

Low-Temperature Synthesis of NaNbO3 Nanopowders and their Thin Films from a Novel Carbon-Free Precursor

We have demonstrated a synthetic procedure for nano-sized NaNbO₃ powder and its thin films using a carbon-free precursor prepared by the reaction of H₂O₂ with sodium and niobium alkoxides. A combination of X-ray powder diffraction, Raman spectra, and thermal gravity and differential thermal analysis, carbon analysis, fourier transform infrared spectra, transmission electron microscopy, and atomic force microscopy was used to characterize the resulting materials and precursor compounds. Results show that this procedure demonstrates the major advantages of low-temperature synthesis (∼400°C) and low weight loss during transformation into NaNbO₃ because of its carbon-free nature, which also provides the option of preparing nano-sized particles and dense, crack-free NaNbO₃ thin films.     

Persistent chorea following cardiac surgery for congenital heart disease

We describe a 6 year old girl with chorea following cardiac surgery, the first such report in Japan. The radical operation for total anomalous pulmonary venous return was carried out at the age of 11 months under hypothermia. Seven days after the operation, a sudden onset of irritability, dysphagia, chorea, generalized, hypotonia, and complete external ophthalmoplegia were seen. These symptoms diminished gradually, but chorea remained. We speculated that the cause of chorea arose from the cardiac surgery under hypothermia. It is necessary to consider 'cardiac surgery' as one of the triggers of certain movement disorders including chorea. We tried treatment with haloperidol, pimozide, and several other drugs; only pimozide was effective in decreasing chorea without any side-effects.     

T cell response to Borrelia garinii, Borrelia afzelii, and Borrelia japonica in various congenic mouse strains

The infectivity and T cell response to Borrelia garinii SIKA2, Borrelia afzelii BFOX, and Borrelia japonica 0612, the organisms that cause Lyme disease in Japan, were examined in various inbred and congenic strains of mice. Infectivity differed among the species: B. garinii SIKA2 and B. afzelii BFOX were each able to infect 90% to 100% of C3H/He mice; B. japonica 0612 was able to infect only 20% of C3H/He mice. The pattern of infectivity to various inbred and congenic strains of mice may influence the pathogenicity of the organism and the clinical signs of Lyme disease. Cross-reactivity between Borrelia antigens was observed, but there was no cross-reactivity between Borrelia antigens and Leptospira antigens. We evaluated the genetic control of the delayed-type hypersensitivity (DTH) reaction in the form of footpad swelling produced by Borrelia antigens using viable or sonicated bacteria as sensitization. Differences in strains of mice infected by viable antigen were observed. However, all strains of mice showed a strong DTH reaction using sonicated antigens without genetic background. A DTH reaction in the form of footpad swelling did not appear to be associated with genetic background. The footpad reaction was mediated by CD4+8- and Ia- T cells, as revealed by in vitro monoclonal antibody treatment. However, CD8+ T cells did not suppress footpad swelling. These results indicate that many antigenic epitopes of the Borrelia spirochete can stimulate the DTH reaction.     

Muscle-specific calpain, p94, responsible for limb girdle muscular dystrophy type 2A, associates with connectin through IS2, a p94-specific sequence

p94, a muscle-specific member of calpain family, is unique in that it undergoes rapid and exhaustive autolysis with a half-life of less than 1 h resulting in its disappearance from muscle. Recently, p94 was shown to be responsible for limb girdle muscular dystrophy type 2A. To elucidate the muscular proteolytic system mediated by p94 and to solve the mystery of its unusually rapid autolysis, we searched for p94-binding proteins by the two-hybrid system. Although calpain small subunit plays a crucial role for regulation of ubiquitous calpains, it did not associate with p94. After a screening of skeletal muscle library, connectin (or titin), a gigantic filamentous protein spanning the M- to Z-lines of muscle sarcomere, was found to bind to p94 through a p94-specific region, IS2. The connectin-insoluble fraction of washed myofibrils contained full-length intact p94, suggesting that connectin regulates p94 activity.     

Three-layer wave absorber using common building material for wireless LAN

A wave absorber with three layers using only common building material for wireless LAN is introduced. The design method is shown, and a suitable structure by fibre reinforced cement board is presented. Based on this, the validity of the experimental absorber produced by this method is confirmed by comparison with calculated results.