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The understanding of the lateral morphology stability of thin polymer devices is of fundamental importance. In this work, the lateral morphology in a model system consisting of thin polymer films capped with thin metal layers on a Si substrate is investigated. When the model system is heated above a critical temperature, a characteristic surface topographic structure is observed that has a well‐defined periodicity but random orientation. It is shown that the minimum temperature, Tmin, required for the surface pattern to be observed decreases with increasing polymer‐film thickness. Increasing either the metal‐ or polymer‐layer thickness increases the characteristic wavelength of the topography. It is believed that the dominating driving force for the surface corrugated‐pattern formation is the thermal‐expansion‐coefficient mismatch of the capping layer and the substrate. A theoretical model based on local bending of a thin, stiff surface film on a thin, elastic medium is used to provide a quantitative analysis of the surface morphology. The calculated minimum temperature required for the surface morphology and the periodicity of the surface patterns to form are in strong agreement with the experimental results. By contrast, systems with prefabricated topographic patterns within any of the three layers (polymer, metal, substrate) produce highly anisotropic surface topographies aligned perpendicular to the prefabricated topographic structure. It is also found that, in a model system with pre‐patterned polymer films, a much higher critical temperature is required for the surface morphology to be observed. The changes in apparent stability and morphological orientation in the pre‐patterned systems can be understood as a result of the anisotropic release of the lateral surface stress during the heat treatment.

Conventional elastoplasticity is based on the idealisation that the interior of the yield surface is a purely elastic domain. This idealisation would not lead to unrealistic prediction of hardening behaviour, but would cause unrealistic prediction of softening behaviour, which is observed typically in overconsolidated soils, whereas metals and normally consolidated soils exhibit hardening behaviour. By contrast, unconventional elastoplasticity that does not use this idealisation makes it possible to describe the plastic deformation due to the change of stress inside the yield surface exhibiting a smooth elastic–plastic transition, and is thus expected to describe softening behaviour more accurately. In this paper the capabilities of conventional and unconventional elastoplasticity for describing softening behaviour are examined, comparing the Drucker–Prager model as the conventional one and the subloading surface model as the unconventional one for predicting the deformation behaviour of overconsolidated soils. It is concluded that unconventional elastoplasticity has to be adopted for predicting softening behaviour.

Summary.: Previous studies showed that the cellular amino acid composition obtained by amino acid analysis of whole cells, differs such as eubacteria, protozoa, fungi and mammalian cells. These results suggest that the difference in the cellular amino acid composition reflects biological changes as the result of evolution. However, the basic pattern of cellular amino acid composition was relatively constant in all organisms examined. In the present study, we examined archaeobacteria, because they are considered important in understanding the relationship between biological evolution and cellular amino acid composition. The cellular amino acid compositions of Archaeoglobus fulgidus, Pyrococcus horikoshii, Methanobacterium thermoautotrophicum and Methanococcus jannaschii differed slightly from each other, but were similar to those determined from codon usage data, based on the complete genomes. Thus, the cellular amino acid composition reflects biological evolution. We suggest that primitive forms of life appearing on earth at the end of prebiotic evolution had a similar-cellular amino acid composition.

Summary.: The cellular amino acid composition of plant cells was analyzed. The callus of carrot (Daucus carota), leaves of Torenia fournieri and protocomb-like body of Cymbidium, s.p. were examined as examples of plant cells. The cellular amino acid compositions differed in the plant cells, but their basic patterns were quite similar. It is concluded that the basic pattern of the cellular amino acid composition is conserved in all terrestrial organisms, including plants.

The copper concentrations in organs of developing Long-Evans Cinnamon (LEC) rats (2 d to 13 mo) were measured to elucidate the pathogenesis of their hereditary hepatitis. Hepatic copper contents of LEC rats were significantly higher than those of control rats (26 to 92 times higher). The subcellular distribution of hepatic copper indicated that the nuclear and large granular fractions had been saturated and the cytosol fraction contained about 70 of all the hepatic copper in LEC rats. The serum concentrations of copper and ceruloplasmin were significantly lower than those of control rats from the 4th wk (10–12 and 5–19, respectively). Copper contents in kidney of LEC rats did not exhibit an increase over those of control rats until 12 wk, but then increased to nearly 40 times higher during fulminant hepatic failure. Accumulation of copper was not detected in the brain or small intestines of LEC rats until 13 mo. The hepatic copper concentration, its subcellular distribution, and serum copper concentration of Fl rats (LEC x Long-Evans Agouti) exhibited the same levels as those of Long-Evans Agouti rats. In addition to their similarity concerning inheritance of autosomal recessive means and clinical course, we found causality relating copper accumulation to the pathogenesis of the disease. We propose that LEC rats will be the most promising animal model for the study of Wilson's disease.

Immunization and intraperitoneal challenge of DBA/2 mice with L5178Y lymphoma cells results in the suppression and maintenance of the L5178Y cells in a tumor-dormant state in the peritoneal cavity for many months. Cell-mediated immune responses involving lymphocytes and macrophages are involved in maintenance of the tumor-dormant state. Macrophages that have increased immunosuppressive activity and that produce increased amounts of PGE2 appear in the peritoneal cavity of tumor-dormant mice before the breakdown of the tumor-dormant state and formation of ascitic tumors. We report here that the tumor-dormant state can be terminated with formation of ascitic tumors by treatment of tumor-dormant mice with PGE2. Treatment with indomethacin results in inhibition of tumor cell growth and elimination of all recoverable tumor cells. Cultures of peritoneal cells (PC) from mice harboring L5178Y cells in a tumor-dormant state were used to analyze the PGE2 and indomethacin effects. Tumor cells did not grow out in the high-cell density PC cultures prepared from many tumor-dormant mice, but addition of PGE2 to these cultures resulted in tumor cell growth. The tumor cell growth that did occur in the PC cultures from some tumor-dormant mice was associated with PGE2 production by the associated host cells, and the addition of indomethacin to these cultures inhibited both PGE2 synthesis and tumor cell growth. Removal of plastic-adherent cells from the PC cultures eliminated the restraint on tumor cell growth. These experiments suggest that L5178Y tumor cells are maintained in a tumor-dormant state by host peritoneal cells, which are under PGE2 regulation.

ABSTRACT: The copper concentrations in organs of developing Long-Evans Cinnamon (LEC) rats (2 d to 13 mo) were measured to elucidate the pathogenesis of their hereditary hepatitis. Hepatic copper contents of LEC rats were significantly higher than those of control rats (26 to 92 times higher). The subcellular distribution of hepatic copper indicated that the nuclear and large granular fractions had been saturated and the cytosol fraction contained about 70% of all the hepatic copper in LEC rats. The serum concentrations of copper and ceruloplasmin were significantly lower than those of control rats from the 4th wk (10–12% and 5–19%, respectively). Copper contents in kidney of LEC rats did not exhibit an increase over those of control rats until 12 wk, but then increased to nearly 40 times higher during fulminant hepatic failure. Accumulation of copper was not detected in the brain or small intestines of LEC rats until 13 mo. The hepatic copper concentration, its subcellular distribution, and serum copper concentration of Fl rats (LEC x Long-Evans Agouti) exhibited the same levels as those of Long-Evans Agouti rats. In addition to their similarity concerning inheritance of autosomal recessive means and clinical course, we found causality relating copper accumulation to the pathogenesis of the disease. We propose that LEC rats will be the most promising animal model for the study of Wilson's disease.

Objective: Geographic differences in the prevalence of hip osteoarthritis (OA) have been ascribed to differences in the frequency of acetabular dysplasia among different ethnic groups. However, there are few data on the shape of the acetabulum in various populations around the world. We examined this issue in samples of pelvic radiographs from Britain and Japan.Methods: Measurements were made on the pelvic radiographs of 1303 men and 195 women, aged 60-75 yr, who attended for i.v. urography in two British centres. These were compared with 99 men and 99 women aged 60-79 yr who were included in a population-based study in a rural community in Japan and who agreed to undergo standardized pelvic radiography. Acetabular dysplasia was assessed by morphometric measurement of the centre-edge (CE) angle and acetabular depth.Results: The mean CE angle among men was 36° (95% CI 35-37°) in Britain and 21° (95% CI 29-32°) in Japan; that in women was 37° (95% CI 36-38°) in Britain and 31° (95% CI 29-33°) in Japan. The mean values of acetabular depth were also significantly (P <0.001) lower in Japan than in Britain. However, the prevalence of hip OA was lower in Japan (0% in men, 2% in women) than in Britain (11% in men, 4.8% in women). In a random effects model, there were negative relationships between measures of acetabular dysplasia and minimum joint space among individuals.Conclusions: We conclude that there are marked differences in pelvic morphometry between Britain and Japan. The acetabular dimensions of Japanese subjects are considerably shallower than those of their British counterparts of similar age and sex. Nevertheless, hip OA is more frequent in Britain than in Japan. Further studies are required on the risk factors for hip OA in Oriental populations, in order that the aetiology of this disorder can be better understood.Key words: Acetabular dysplasia, Hip, Osteoarthritis, Pelvic morphometry, Britain, Japan.

Objective: Geographic differences in the prevalence of hip osteoarthritis (OA) have been ascribed to differences in the frequency of acetabular dysplasia among different ethnic groups. However, there are few data on the shape of the acetabulum in various populations around the world. We examined this issue in samples of pelvic radiographs from Britain and Japan.
Methods: Measurements were made on the pelvic radiographs of 1303 men and 195 women, aged 60-75 yr, who attended for i.v. urography in two British centres. These were compared with 99 men and 99 women aged 60-79 yr who were included in a population-based study in a rural community in Japan and who agreed to undergo standardized pelvic radiography. Acetabular dysplasia was assessed by morphometric measurement of the centre-edge (CE) angle and acetabular depth.
Results: The mean CE angle among men was 36° (95% CI 35-37°) in Britain and 21° (95% CI 29-32°) in Japan; that in women was 37° (95% CI 36-38°) in Britain and 31° (95% CI 29-33°) in Japan. The mean values of acetabular depth were also significantly (P &lt;0.001) lower in Japan than in Britain. However, the prevalence of hip OA was lower in Japan (0% in men, 2% in women) than in Britain (11% in men, 4.8% in women). In a random effects model, there were negative relationships between measures of acetabular dysplasia and minimum joint space among individuals.
Conclusions: We conclude that there are marked differences in pelvic morphometry between Britain and Japan. The acetabular dimensions of Japanese subjects are considerably shallower than those of their British counterparts of similar age and sex. Nevertheless, hip OA is more frequent in Britain than in Japan. Further studies are required on the risk factors for hip OA in Oriental populations, in order that the aetiology of this disorder can be better understood.