Showing papers by "Nagoya University published in 1979"

Relation of pancreatic duct hyperplasia to carcinoma.

Abstract: In order to find a relationship between ductal hyperplasia and carcinoma of the pancreas, histological and histochemical examinations were made on pancreatic specimens of 1,174 autopsy patients with special attention to the age incidence of the former. Ductal hyperplasia was divided into 3 types; nonpapillary, papillary, and atypical hyperplasia. All three types of hyperplasia and ductal carcinoma showed a similar tinctorial property in mucous histochemistry. In general, atypical hyperplasia was seen in the pancreas having papillary hyperplasia which was found in the pancreas associated with nonpapillary hyperplasia. All three types of hyperplasia were apparently more frequent in cancerous pancreases than in non-cancerous ones. They were also more common in the head of the pancreas than in the body and tail. Age incidence also suggests a sequential change from nonpapillary hyperplasia through papillary and atypical ones to carcinoma.

New integrable nonlinear evolution equations

Abstract: A new series of integrable nonlinear evolution equations is presented. The equations are novel in the sense that the nonlinear terms have saturation effects. It is shown that the equations have an infinite number of conservation laws and can be expressed in the Hamiltonian form.

A generalization of inverse scattering method

Abstract: A new scheme of the inverse scattering method is proposed. As an illustration of novel feature of our scheme, the set of fundamental equations has been presented for a generalized nonlinear Schrodinger equation, of which nonlinear terms are composed of a usual cubic nonlinear term and a derivative cubic nonlinear term.

Enzymic mechanisms of starch breakdown in germinating rice seeds: 7. Amylase formation in the epithelium

Abstract: The time sequence analysis of the starch digestion pattern of the thin sectioned germinating rice (Oryza sativa L) seed specimens using the starch film method showed that at the initial stage amylase activity was almost exclusively localized in the epithelium septum between the scutellum and endosperm Starch breakdown in the endosperm tissues began afterward; amylase activity in the aleurone layers was detectable only after 2 days Polyacrylamide gel electrofocusing (pH 4 to 6) revealed nearly the same zymogram patterns between endosperm and scutellum extracts, although additional amylase bands appeared in the endosperm extracts at later germination stages (4 to 6 days) These are presumably attributable to the newly synthesized enzyme molecules in the aleurone cells

Kink-Antikink Collisions in the Two-Dimensional φ4 Model

Abstract: Inelastic kink-antikink collisions are investigated in the two-dimensional ¢' model. It is shown that a bound state of the kink and antikink is formed when the colliding velocity V is less than a critical V" and that inelastic scattering of the kinks is caused when V> V,. These phenomena are due to the excitation of internal modes of the kinks. An excited kink is not stable but emits bosuns to decay into the ground state kink. Numerical calculations were also performed for classical kink-antikink collision processes. A large class of non-linear field equations has localized stable soh;tions which are called solitons. The quantum theory of soliton has been studied by many authors aiming at constructing a model of extended particles. Semi-classical meth­ ods have been applied to the quantization of a soliton and the systematic pertur­ bation theories have been developed at least in one-soliton sector.n' 2 ' However, we have no satisfactory treatment of the quantum scattering of solitons. 3l In the strict meaning used in mathematical literature, solitons are stable even against collisions. Since this stability is guaranteed by an infinite number of con­ served quantities,·') these solitons are scattered elastically also in quantum theory. The sine-Gordon model provides a good example of such solitons. In particle physics, however, it may be useful to understand solitons in a broad sense. That is, if a field equation has a classical solution vvhose energy is localized in a finite volume and which is stable against small fiuctional variations, we call it a soliton solution. In this sense, there are solitons which are unstable against a collision, and it is important to study inelastic scattering of such solitons. In this paper, we investigate soliton-antisoliton collision processes m the two­ dimensional ¢4 model as an example of the inelastic scattering of solitons. The two-dimensional ¢4 model has the so-called kink solutions and a fluctuation mode trapped in the kink. The kinks are scattered inelastically because of the excitation of the internal modes. In §§ 2 and 3, we introduce a collective coordinate into a kink-antikink system and derive the equations of motion for the system. Solving the equations approximately, we estimate the excitation probability of the internal

THE ELASTIC CONSTANTS OF Mn2SiO4, Fe2SiO4 AND Co2SiO4, AND THE ELASTIC PROPERTIES OF OLIVINE GROUP MINERALS AT HIGH TEMPERATURE

Abstract: Elastic constants of single-crystal Mn2SiO4, Fe2SiO4 and Co2SiO4 olivine are measured by the rectangular parallelepiped resonance (RPR) method at temperatures between 20° and 400°C. Elastic constants Cij (Mbar) and their temperature derivatives ∂Cij/∂T (kbar/deg) are: The isotropic properties, density ρ, adiabatic bulkmodulus K3, rigidityμ, the Poisson's ratio σ, and their temperature derivatives calculated by the Voigt-Reuss-Hill scheme are: By combining the present results with the previous data on a magnesium rich olivine, the effect of cation substitution on the elastic properties of olivine group minerals is discussed and the elastic constants of olivine at high temperature in the earth's mantle are clarified.

Thermal expansion of .GAMMA.-Mg2SiO4.

Abstract: Thermal expansion of γ-Mg2SiO4 was measured with X-ray powder diffraction method up to 750°C at atmospheric pressure. The data are analyzed in terms of Gruneisen's theory of thermal expansion and Gruneisen's parameter is obtained to be 1.27. Volume thermal expansion coefficient is 19 at 20°C and 27 at 500°C in unit of 10-6/K. These values are compared with those of γ-Fe2SiO4, MgAl2O4 and other spinel type compounds, and it is suggested that the anharmonic properties of γ-(Mg, Fe)2SiO4 may be very close to those of MgAl2O4.

High density cultivation of biomass in fed-batch system with do-stat

Abstract: Escherichia coli and Candida brassicae were cultivated in a fed-batch culture with a DO-stat under the condition that none of the components in the basal medium limited the growth of the microorganism. High densities of biomasses (125 g/l for E. coli and 138 g/l for C. brassicae) were obtained. The final biomasses obtained in the cultivations of E. coli and C. brassicae corresponded to 57% and 51%, respectively, of the limits that the organisms can be cultivated in view of viscosity of the broth. Metabolic products in the supernatant of the broth at the end of the cultivation and concentration of carbon dioxide in exit gas from the fermentor were measured, and the relations between cell concentration and growth yield with respect to carbon source were shown. It was considered that the decreases in growth yield and specific growth rate in the case of E. coli were due to the metabolites, including CO2, which increased to inhibitory concentrations. On the other hand, the possibility of obtaining a higher density of biomass was shown in the case of C. brassicae if a fermentor with higher oxygen transfer rate were used. Merits of using pure oxygen gas for production of biomass were exemplified.

The Space Charge Behavior and Luminescence Phenomena in Polymers at 77 K

Abstract: Electroluminescence phenomena were observed at the needle tip in polymer samples with a point-plane electrode system under an applied ac voltage at liquid nitrogen temperatures. This luminescence was considered to be caused by the recombination between positive and negative charges injected from the point electrode. The nature and behavior of the charges injected into the polymer became clear through a detailed study of luminescence. A degenerate rate region of polymer was also found at the needle tip after prolonged ac voltage application, which may indicate a depolymerized region caused by the attack of then injected charges. The fact that tree channels started from the degenerate region in the polymer led us to theon conclusion that the injection of charge can be hazardous for polymer solid insulation systems.

Partial characterization and aspects of the mode of action of a hypersensitivity-inhibiting factor (HIF) isolated from Phytophthora infestans

Abstract: Factors which inhibit the hypersensitive reaction of potato tuber tissue (Kennebec, R1) to Phytophthora infestans were isolated from mycelia and zoospores of race 1234 (compatible) and race 4 (incompatible) of the fungus. They were partially characterized as glucans containing β-1→3 and β-1→6 linkages and 17 to 23 glucose units. The glucans from both mycelia and zoospores included a non-anionic glucan and an anionic glucan; one or two residues of the latter were esterified with a phosphoryl monoester. Death of host cells, browning and the accumulation of rishitin (hypersensitive reaction) in tuber slices inoculated with race 4 or treated with an elicitor from the fungus were suppressed by pretreatment of slices with the glucans. The glucans from the compatible race were more active in suppressing the hypersensitive reaction than those from the incompatible race. The anionic glucan was more active than the non-anionic glucan. Crude elicitors from races 4 and 1234 lost terpenoid-eliciting activity when mixed with a microsomal fraction prepared from potato tuber tissue. The glucans from the compatible race, but not the incompatible race, markedly reduced the loss resulting from the reaction between the crude elicitor and the microsomal fraction. The data suggest that the compatible interaction between potato tissue and P. infestans may be caused by a suppression of the hypersensitive response of the host tissue by water-soluble glucans from the fungus.

Solid‐State Ionics: High Copper Ion Conductivity of the System CuCl ‐ CuI ‐ RbCl

Abstract: A new high copper ion conductivity solid electrolyte has been found in the system. This compound has a copper ion conductivity of 0.34 (Ω‐cm)−1 at 25°C, and activation energies for conduction of 7.0 kJ/mole between 130°C and −25°C, and 19 kJ/mole between −25°C and −140°C, respectively. Powder x‐ray diffraction analysis indicates that the crystal structure of is simple cubic with .

Stable state estimator for bilinear systems

Abstract: This paper considers a stable state observer for bilinear systems. The design of the proposed observer is based on Lyapunov stability and the norm of the estimation error decays to zero exponentially irrespective of the input, although the estimation error itself depends on the input. Sufficient conditions are given for the existence of a stable observer. These conditions make it possible to design a stable observer for a class of bilinear systems, which has no observer by the other method.

MELTING RELATION OF Fe2SiO4 UP TO ABOUT 20Okbar

Abstract: The melting relations in fayalite Fe2SiO4 and its high pressure modification γ-Fe2SiO4 have been experimentally studied at pressures up to about 200kbar. Fayalite melts congruently up to the triple point, 70±5kbar and 1, 520±25°C, of fayalite, γ-Fe2SiO4, and liquid. The initial slope of γ-Fe2siO4 is about 12°/kbar. γ-Fe2siO4 melts congruently up to about 130 kbar, above which it melts incongruently into stishovite SiO2 and liquid. The incongruent melting in γ-Fe2SiO4 terminates at about 170kbar and 2, 200°C. Above this pressure, the melting mode switches to the eutectic melting between wustite Fe1-xO and stishovite SiO2, which are the post γ-Fe2SiO4 assembly. The present data suggest a possibility of incongruent melting of γ-(Mg, Fe)2SiO4 at high pressure. Possible roles of the change in melting mode on the chemical fractionation of the earth's mantle are discussed.

Further Investigations on Magnetic Properties of Co(S x Se 1− x ) 2 , (0≤ x ≤1)

Abstract: Further investigations, succeeding to the works of J. Phys. Soc. Japan 26 (1969) 631 and 29 (1970) 323, on the magnetic properties of Co(S x Se 1- x ) 2 in the whole concentration ranges (0≤ x ≤1) were performed by means of high magnetic field, electrical resistivity and low temperature X-ray diffraction measurements. The first kind magnetic transition was found in the ferromagnetic phase except CoS 2 . The metamagnetic behaviors were observed in the ferromagnetic (0.89< x <1.0) as well as paramagnetic ( x <0.89) phases. The saturation moment per Co atom was obtained to be 0.855 µ B for CoS 2 and it decreased gradually with increasing Se content. The electrical resistivity in low temperatures showed a T 2 -dependence. It was concluded that the itinerant electron model base on the spin fluctuation theory is more adequate than models based on a localized spin scheme.

Non-Stochastic Heating of Magnetized Plasma by Electrostatic Wave

Abstract: When an electrostatic wave is suddenly applied, initially trapped particles suffer a rapid, large acceleration as well as the stochastic heating, while initially untrapped particles suffer only the stochastic heating. When the bounce frequency ω B is larger than (ω c ω) 1/2 , the initially trapped particles mainly absorb the wave energy and form a high energy tail. The results are applied to the problem of energetic ion creation in laser fusion plasma and of a high energy tail formation in a plasma heated by the lower hybrid wave.

Study of Complex Coacervation in Low Concentration by Virial Expansion Method. I. Salt Free Systems

Abstract: Complex coacervation is explained with the assumption that the symmetrical aggregate polymer (SAP) model is applicable to both dilute and concentrated phases. An interaction potential between SAP's is obtained in a way similar to the derivation of the Flory-Krigbaum potential between usual polymers. Using this potential, osmotic pressure P is obtained by the virial expansion method. The curve of P (vs volume fraction of SAP) corresponds to the curve of pressure (vs volume) representing gas-liquid phase separation. Moreover the self-suppression is quantitatively explained by the contraction of SAP dimension.