Showing papers by "University of Tokyo published in 1984"
TL;DR: The system described here gives a direct and precise method for determining DNA base composition by reversed-phase high-performance liquid chromatography (HPLC).
Abstract: DNA base composition was determined by reversed-phase high-performance liquid chromatography (HPLC). DNA was hydrolysed into nucleosides with nuclease P1 and bacterial alkaline phosphatase. The mixture of nucleosides was applied to HPLC without any further purification. One determination by chromatography needed 2 μg of hydrolysed nucleosides and took only 8 min. The relative standard error of nucleoside analysis was less than 1%. The system described here gives a direct and precise method for determining DNA base composition.
2,468 citations
TL;DR: The linear perturbation theory of spatially homogeneous and isotropic universes is reviewed and reformulated extensively in this article, with special attention paid to the geometrical meaning of the perturbations.
Abstract: The linear perturbation theory of spatially homogeneous and isotropic universes is reviewed and reformulated extensively. In the first half of the article, a gauge-invariant formulation of the theory is carried out with special attention paid to the geometrical meaning of the perturbation. In the second half of the article, the application of the theory to some important cosmological models is discussed.
1,443 citations
Book•
27 Jan 1984TL;DR: The Earth References Index as discussed by the authors is a collection of articles about the physical chemistry and cosmochemistry of the Earth that can be found in the Google Docs directory. But they are not related to this paper.
Abstract: 1. Introduction 2. Physical chemistry 3. Cosmochemistry 4. Waters 5. Crust 6. The Mantle 7. Noble gases in the Earth References Index.
1,102 citations
TL;DR: A new simple method of detecting calcium binding proteins in a protein mixture is described that can detect as little as 2 micrograms of calcium binding protein in the starting sample and under appropriate conditions it was possible to detect only high affinity calciumbinding proteins.
Abstract: A new simple method of detecting calcium binding proteins in a protein mixture is described. A sample which might include calcium binding proteins was subjected to SDS-polyacrylamide gel electrophoresis and then electrophoretically transferred to a nitrocellulose membrane. The membrane was then incubated with 45Ca to detect calcium binding proteins as radioactive bands by autoradiography. Purified troponin-C, calmodulin, myosin DTNB light chain, and parvalbumin were clearly identified by this method. In the whole homogenate of chicken skeletal muscle, myosin DTNB light chain, troponin-C, and 55K calcium binding protein were found to be radioactive. In the frog skeletal muscle, small molecular weight proteins of approximately 13-15K and 70K protein appeared to be the calcium binding proteins. In the case of the carp skeletal muscle, small molecular weight proteins including parvalbumin and two proteins of about 80K seemed to bind calcium ion. Two high molecular weight calcium binding proteins were present in the scallop striated muscle. The procedure described can be completed within 24 h and can detect as little as 2 micrograms of calcium binding protein in the starting sample. Under appropriate conditions it was possible to detect only high affinity calcium binding proteins.
744 citations
TL;DR: In this article, the authors have developed five kinds of biped locomotive robots, named BIPER-1, 2, 3, 4, and 5, which are all statically unstable but can perform a dynamically stable walk with suitable control.
Abstract: The authors have developed five kinds of biped locomotive robots so far. They are named BIPER-1, 2, 3, 4, and 5. All of them are statically unstable but can perform a dynamically stable walk with suitable control. BIPER-1 and BIPER-2 walk only sideways. BIPER-3 is a stilt-type robot whose foot contacts occur at a point and who can walk sideways, back ward, and forward. BIPER-4's legs have the same degrees of freedom as human legs. BIPER-5 is similar to BIPER-3, but in the case of BIPER-5 all apparatus, such as the computer, are mounted on it.This paper deals with the control theory used for BIPER-3 and BIPER-4. In both cases, basically the same control method is applied. The most important point is that the mo tion of either robot during the single-leg support phase can be approximated by the motion of an inverted pendulum. Ac cordingly, in this paper, dynamic walk is considered to be a series of inverted-pendulum motions with appropriate condi tions of connection.
475 citations
TL;DR: In this article, the electronic structure of the insulating antiferromagnetic transition-metal compounds MnO, FeO, CoO, and NiO is discussed with use of energy-band theory based on the local-spin-density treatment of exchange and correlation.
Abstract: The electronic structure of the insulating antiferromagnetic transition-metal compounds MnO, FeO, CoO, and NiO, which have been regarded as the prototypes of the concept of a Mott insulator, is discussed with use of energy-band theory based on the local-spin-density treatment of exchange and correlation. It is shown that the band structure is very sensitive to the magnetic ordering and that the ground-state magnetic ordering is special in the sense that it makes the ${e}_{g} ({x}^{2}\ensuremath{-}{y}^{2},3{z}^{2}\ensuremath{-}{r}^{2})$ band particularly narrow, which is crucial to the insulating nature of NiO. A detailed analysis is made of this particular aspect of the ground-state magnetic ordering. As for FeO and CoO, it is suggested that the population imbalance among the ${t}_{2g} (xy, yz, zx)$ orbitals induced by the intra-atomic exchange interaction may cause a gap to open at the Fermi level.
447 citations
TL;DR: Analysis of natural utterances of various declarative sentences of Japanese revealed that the model can generate close approximations to observed F0 contours from a set of discrete commands and a small number of parameters.
Abstract: A model for the generation of fundamental frequency contours (F0 contours) of spoken, sentences is presented for the purpose of elucidating the relationship between the sentence F0 contour and the linguistic and non-linguistic information. It is based on a quantitative formulation of the process whereby the logarithmic fundamental frequency is controlled in proportion to the sum of two components corresponding respectively to the effects of phrase and accent. The model's parameters were determined to give the best approximation to an observed F0 contour on the basis of the mean squared error. Analysis of natural utterances of various declarative sentences of Japanese revealedthat the model can generate close approximations to observed F0 contours from a set of discrete commands and a small number of parameters. The extracted parameters were found to be closely related to linguistic factors and factors constituting thenaturalness of speech. These results provide a means for generating natural F0 contours from a small set of parameters and rules for synthesis.
437 citations
TL;DR: The fecal flora of 35 breast‐fed and 35 bottle‐fed babies was determined and the organism that showed the highest number and the highest frequency of occurrence in both groups was Bifidobacterium breve.
Abstract: The fecal flora of 35 breast-fed and 35 bottle-fed babies was determined. Bifidobacteria were the predominant fecal bacteria in both groups. Conversely, the counts of most of the other bacteria, such as bacteroides, eubacteria, peptococci, veillonella, clostridia, enterobacteria, streptococci, and bacilli in the bottle-fed group were significantly higher than those in the breast-fed group. The frequencies of occurrence of lecithinase positive Clostridia, clostridia-others, pseudomonas and bacilli in the bottle-fed group were significantly higher than those in the breast-fed group. Twenty-one genera and 103 species or biovars of microorganisms were isolated from the feces of the breast-fed group and 20 genera and 97 species or biovars from the bottle-fed group. The organism that showed the highest number and the highest frequency of occurrence in both groups was Bifidobacterium breve. Bifidobacterium infantis, which was formerly the most prevalent Bifidobacterium species in baby feces, was never isolated in this study. Further, the counts and incidences of Clostridium paraputrificum, C. perfringens, and Bacillus subtilis, the counts of C. clostridiiforme, Bacteroides vulgatus, Veillonella parvula, Lactobacillus acidophilus, Escherichia coli, Streptococcus bovis, S. faecalis, and S. faecium and the incidences of C. difficile, C. tertium, and Pseudomonas aeruginosa in the bottle-fed infants were significantly higher than those in the breast-fed infants.
409 citations
TL;DR: Results are consistent with the hypothesis that, in A431 cells, gene amplification, possibly associated with a translocation event, may result in the overproduction of EGF receptor protein or the appearance of the transformed phenotype (or both).
Abstract: The sequence of the human epidermal growth factor (EGF) receptor shows great homology with the avian erythroblastosis virus v-erb B oncogene, raising the possibility that the receptor gene is identical to the c-erb B protooncogene. Human A431 epidermoid carcinoma cells, which have an unusually high number of EGF receptors, were examined to determine whether elevated EGF receptor levels correlate with gene amplification. Southern blots of genomic DNA's from A431 and other human cell lines were probed with either a v-erb B gene fragment or a human EGF receptor complementary DNA clone (pE7), previously isolated from an A431 complementary DNA library. When either probe was used to analyze Eco RI- or Hind III-generated DNA fragments, EGF receptor DNA sequences were amplified about 30-fold in A431. Differences in the banding pattern of A431 DNA fragments relative to normal fibroblast DNA indicate the occurrence of a rearrangement in the region of the receptor gene. Furthermore, A431 cells contain a characteristic, prominent 2.9-kilobase RNA. These results are consistent with the hypothesis that, in A431 cells, gene amplification, possibly associated with a translocation event, may result in the overproduction of EGF receptor protein or the appearance of the transformed phenotype (or both).
394 citations
TL;DR: Fresh submarine basalt glasses from Galapagos Ridge, FAMOUS area, Cayman Trough and Kilauea east rift contain 22 to 160 ppm carbon and 0.3 to 2.8 ppm nitrogen, respectively, as the sums of dissolved species and vesicle-filling gases (CO2 and N2).
380 citations
TL;DR: Chicken skeletal muscle myosin alkali light chains are encoded by a single gene of size 18 kilobases (kb), which has two transcription initiation sites from which 17.5- and 8-kb precursor RNAs are transcribed.
Abstract: Chicken skeletal muscle myosin alkali light chains are encoded by a single gene of size 18 kilobases (kb). This gene has two transcription initiation sites from which 17.5- and 8-kb precursor RNAs are transcribed. These RNAs are processed by different modes of splicing to form mRNAs encoding distinct light-chain (LC1 and LC3) proteins.
TL;DR: A surprisingly high association between an HLA-DR locus antigen and narcolepsy was revealed in the Japanese, and data suggested that a "disease" allele predisposing to narcoLEpsy was inherited with relatively rare haplotypes with DR2 in theJapanese.
Abstract: A surprisingly high association between an HLA-DR locus antigen and narcolepsy was revealed in the Japanese. All 40 Japanese patients with narcolepsy (22 males and 18 females) were confirmed to be DR2 positive. However, the DR2 of the patients was found to associate negatively with Bw52, whereas Bw52-DR2 is the commonest haplotype in normal Japanese population. These data suggested that a "disease" allele predisposing to narcolepsy was inherited with relatively rare haplotypes with DR2 in the Japanese.
TL;DR: TNF from mice had an antitumor activity against not only murine tumors but also human tumors, and in addition to direct cytotoxicity against tumor cells, TNF induced a host‐mediated factor which contributed to the antitumors effects.
Abstract: The antitumor activity of highly purified tumor necrosis factor (TNF) was tested against eight kinds of murine tumor and five kinds of human tumor heterotransplanted into nude mice. Mice were treated by intravenous or intratumoral injection of TNF, commencing when the tumors were well established. TNF showed an excellent curative effect against all kinds of murine and human tumors tested. Meth A sarcoma, Colon 26, Ehrlich, sarcoma 180, MM 46, MH 134, B16 melanoma, and Lewis lung tumors transplanted into mice underwent tumor necrosis and regression following a single injection of TNF. Sometimes a complete cure was observed in Meth A sarcoma, sarcoma 180, Ehrlich, and MM 46 tumors. Human cancers, SEKI, HMV-I, KATO-III, MKN 45, or KB, heterotransplanted into nude mice, also exhibited tumor necrosis and regression in size following several intratumoral injections of TNF. A great difference in curative effects of TNF was observed in Meth A sarcomas between those transplanted into BALB/c nu/+ and into BALB/c nu/nu mice: following a single intravenous administration the effect was stronger in BALB/c nu/+ than in nu/nu mice. In contrast, tumor necrosis was almost the same in nu/+ and nu/nu mice following intratumoral administration. The present results thus indicate that TNF from mice had an antitumor activity against not only murine tumors but also human tumors. In addition to direct cytotoxicity against tumor cells, TNF induced a host-mediated factor which contributed to the antitumor effects.
TL;DR: On etudie des caracteristiques qualitatives d'un reseau a une dimension d'applications logistiques couplees, on trouve des configurations duales-antiduales de cycles 2 n -periodiques avec leurs bifurcations a dedoublement de periode
Abstract: On etudie des caracteristiques qualitatives d'un reseau a une dimension d'applications logistiques couplees. On trouve des configurations duales-antiduales de cycles 2 n -periodiques avec leurs bifurcations a dedoublement de periode
TL;DR: Multivariate analysis indicated that a diminished insulin response and a high maximal body weight index, as well as a high level of fasting and 2-h glucose values at the initial 100-g oral glucose tolerance test were significant independent risk factors for the development of diabetes in Japanese subjects.
Abstract: In a 5–12 year follow-up study of 288 subjects with impaired glucose tolerance after a 100-g glucose load, 48 worsened to overt Type 2 (non-insulin-dependent) diabetes with the elevation of fasting blood glucose. The initial level of blood glucose was a major predictor of subsequent worsening to diabetes. In addition, subjects with a lower insulin response to glucose showed a higher incidence of worsening to the disease, irrespective of blood glucose levels. Multivariate analysis indicated that a diminished insulin response and a high maximal body weight index, as well as a high level of fasting and 2-h glucose values at the initial 100-g oral glucose tolerance test were significant independent risk factors for the development of diabetes in Japanese subjects.
TL;DR: In this article, an improved version of the generalized correlation is successfully developed, being accompanied with a very clear-cut structure as compared with the previous correlation, and careful experiments have been attempted with an identical test tube covering all the main characteristic regimes of CHF.
TL;DR: In this paper, a simple model which takes into account both adsorption properties and apparatus characteristics was proposed to interpret the experimental results quantitatively, and the transitional behavior of heat and mass transfer in continuous adsorbption-regeneration experiments was successfully interpreted by the model.
Abstract: Fundamental experiments on the solar-powered adsorption cooling system were carried out with small-scale apparatus simulating ideally a practical unit by employing a combination of silica-gel and water vapor as an example of the adsorbent-adsorbate combinations. A simple model which takes into account both adsorption properties and apparatus characteristics was proposed to interpret our experimental results quantitatively. Then the transitional behavior of heat and mass transfer in continuous adsorption-regeneration experiments was successfully interpreted by the model. The model proposed here is not a complete one and is to be considered as a first-step model for estimating operation with practical equipment. Also, the contribution of the level of regeneration temperature of adsorbents to the cooling performance was quantitatively clarified on the basis of the adsorption equilibrium relation, which is considered useful in choosing a favorable combination of adsorbent and adsorbate for the system.
TL;DR: In this article, the reduction of acyclic β-hydroxy ketones via boron chelates via asymmetric induction can be achieved in a highly selective manner.
TL;DR: It may be true, as the poet said, that only God can make a tree, but through geometric modeling a computer graphics system can produce a remarkable likeness.
Abstract: It may be true, as the poet said, that ?...only God can make a tree,? but through geometric modeling a computer graphics system can produce a remarkable likeness.
TL;DR: In this paper, the antiferromagnetic Heisenberg model on the two-dimensional triangular lattice is studied both by topological analysis of defects and by Monte Carlo simulation, and it is shown that the order parameter space of this model is isomorphic to the three-dimensional rotation group SO(3) due to the inherent frustration effect.
Abstract: Ordering process of the antiferromagnetic Heisenberg model on the two-dimensional triangular lattice is studied both by topological analysis of defects and by Monte Carlo simulation. It is shown that the order parameter space of this model is isomorphic to the three-dimensional rotation group SO(3) due to the inherent frustration effect. Homotopy analysis shows that the system bears a topologically stable point defect characterized by a two-valued topological quantum number and exhibits a phase transition driven by the dissociation of the vortices. A Monte Carlo study on the specific heat and the behavior of vortices strongly suggests the occurence of a Kosterlitz-Thouless-type phase transition. It is, however, argued that in contrast to the two-dimensional X Y model, the spin-correlation function decays exponentially even in the low-temperature phase. In order to distinguish the high- and low-temperature phases qualitatively, we introduce a “vorticity function” analogously to the Wilson loop in the quark...
TL;DR: It is suggested that the 33‐kDa polypeptide maintains the binding of Mn to the oxygen‐evolution system and can be functionally replaced by 200 mM Cl−.
TL;DR: In this article, a new method of femtosecond and picosecond transient spectroscopy yielding information about ultrafast relaxation processes without requiring ultrashort light pulses is presented.
Abstract: A new method of picosecond and femtosecond transient spectroscopy yielding information about ultrafast relaxation processes without requiring ultrashort light pulses is presented. It is based on the present theoretical analysis of the resonant degenerate four-wave-mixing process excited by two temporally incoherent light beams with wave vectors ${\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}}_{1}$ and ${\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}}_{2}$ which are originated from a single beam at frequency $\ensuremath{\omega}$ but have mutual time delay $\ensuremath{\tau}$. Under the assumption that the incoherent light field has Gaussian random complex amplitude and that the resonant material consists of the usual two-level atoms, the statistically averaged intensity of the output light field with ${\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}}_{3}=2{\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}}_{2}\ensuremath{-}{\stackrel{\ensuremath{\rightarrow}}{\mathrm{k}}}_{1}$ at $\ensuremath{\omega}$ is calculated as a function of $\ensuremath{\tau}$. Even with the light having a much longer duration than both ${T}_{1}$ (the longitudinal relaxation time) and ${T}_{2}$ (the transverse relaxation time), the correlation trace, i.e., output intensity versus $\ensuremath{\tau}$, represents a decay profile determined mainly by ${T}_{2}$ for both homogeneously and inhomogeneously broadened transitions, as long as the light correlation time ${\ensuremath{\tau}}_{c}$ is much shorter than the relaxation times. The correlation trace does not always represent a single-exponential decay but is sometimes slightly deformed by the ${T}_{1}$ effect. However, it does not cause a significant error in the determination of ${T}_{2}$. Moreover, as $\frac{{T}_{2}}{{T}_{1}}\ensuremath{\rightarrow}0$, the trace becomes a single-exponential decay curve determined only by ${T}_{2}$. The feature of the results obtained by the present method is similar to that obtained by the conventional coherent transient spectroscopy with short pulses, such as the photon echo. The time resolution in the present method, however, is limited only by ${\ensuremath{\tau}}_{c}$ much shorter than the light duration. By regarding the incoherent light as a series of random ultrashort pulses, the present four-wave-mixing process is also interpreted as the ensemble of numerous transient four-wave-mixing processes caused by various combinations of these pulses.
TL;DR: Three molecular forms of prothoracicotropic hormone were isolated from the head of the adult silkworm, Bombyx mori, and the amino acid sequence of 19 amino acid residues in the amino terminus of these prothornicotropic hormones was determined.
Abstract: Three molecular forms of prothoracicotropic hormone were isolated from the head of the adult silkworm, Bombyx mori, and the amino acid sequence of 19 amino acid residues in the amino terminus of these prothoracicotropic hormones was determined. These residues exhibit significant homology with insulin and insulin-like growth factors.
TL;DR: In this article, it is shown that the distribution of the solution to a general Ito equation has the same regularity properties as that of a classical diffusion just so long as the coefficients of the white noise are non-degenerate.
Abstract: Publisher Summary This chapter discusses the application of Malliavin's calculus to various problems in stochastic analysis and the theory of partial differential equations. The chapter examines the regularity estimates on the distribution of functionals to which Malliavin's procedure is applicable. It is shown that solutions of Ito stochastic integral equations are smooth functions in the sense of Malliavin's calculus. The distribution of the solution to a general Ito equation has the same regularity properties as that of a classical diffusion just so long as the coefficients of the white noise are non-degenerate. Any other method, of deducing this result and believing that it is a good example to illustrate the power of Malliavin's calculus, is not known.
TL;DR: Oxygen‐evolution activity was restored almost to the original level with 10 mM Ca2+, in a similar manner to the rebinding of 24‐kDa polypeptide in photosynthetic oxygen evolution in Photosystem II particles.
TL;DR: In this paper, the higher order correction term is obtained for the Monte Carlo calculation of the path integral, expressed only by a modification of the potential term: \(V(\textbf{itshape r}_{1}, \cdots, \textbf{\ithape R}_{N}) \rightarrow V+(\hbar ^{2}/24m)(\beta /M)^{2} \sum _{i=1}^{N} (\partial V/\partial \textBF{\itshAPE r}{i})^{2
Abstract: The higher order correction term is obtained for the Monte Carlo calculation of the path integral. The correction is expressed only by a modification of the potential term: \(V(\textbf{\itshape r}_{1}, \cdots , \textbf{\itshape r}_{N}) \rightarrow V+(\hbar ^{2}/24m)(\beta /M)^{2} \sum _{i=1}^{N} (\partial V/\partial \textbf{\itshape r}_{i})^{2}\), where r i 's are coordinates of particles, N is number of particles with mass m , β is ( k T ) -1 and M is number of partitions. By this method one can reduce the computation time remarkably. A rapid convergence of energy is obtained for the case of harmonic oscillator.
TL;DR: In this paper, a series of large-scale pyroclastic eruptions produced the Aira caldera 20 km×20 km wide at the northern end of Kagoshima Bay in southern Kyushu.
Abstract: About 22,000 years ago a series of large-scale pyroclastic eruptions produced the Aira caldera 20 km×20 km wide at the northern end of Kagoshima Bay in southern Kyushu. It started with a Plinian pumice eruption (Osumi pumice fall, 98 km3) followed by oxidized, fine-grained Tsumaya pyroclastic flow (13 km3), both erupted from a vent located at the present site of Sakurajima volano, 8 km south of the caldera center. After a very short pause, violent explosive ejection of the basement rock fragments and pumiceous materials occurred at the central vent, gradually changing itself to a huge eruption column rapidly collapsing to form the Ito pyroclastic flow about 300 km3 in volume. The earliest phase produced up to 30-m-thick Kamewarizaka breccia developed along the caldera rim and charged with basement (lithic) fragments up to 2 m across. The breccia is a near-vent variety of the bottom concentration zone of lithics in the Ito deposit. Various textural features and monotonous petrologic character indicate that the main part of the Ito pyroclastic flow was emplaced by a simple, short-lived eruptive mechanism. The Aira-Tn ash, a fine-grained counterpart of the Ito pyroclastic flow, covered a wide area more than 1000 km from the vent. Evacuation of more than 110 km3 of rhyolitic magma produced a funnel-shaped collapse structure with the center of the magma chamber about 10 km deep. Like many other Japanese Quaternary calderas, the Aira caldera is considered to heave formed not by a piston cylinder-type subsidence utilizing a ring fracture but by coring and high-angle slumping of the wall rocks into a funnel-shaped central vent. The outline of the caldera was strongly controlled by the faults bounding the volcano-tectonic graben forming Kagoshima Bay.
01 Jan 1984
TL;DR: An experimental study on effects of temperature and pressure on the burning velocity of methane and hydrogen air mixtures has been conducted by using the spherical bomb technique proposed by the present authors as discussed by the authors, and the obtained burning velocities were correlated by the Arrhenius form expression, which is based on the flame theory with a one-step kinetics.
Abstract: An experimental study on effects of temperature and pressure on the burning velocity of methaneair and hydrogenair mixtures has been conducted by using the spherical bomb technique proposed by the present authors. The ranges of measurement covered the equivalence ratio from 0.8 to 1.3 for methaneair, and from 0.5 to 4.0 for hydrogenair mixtures. The mixture temperature was varied from 291 to 500K, while the pressure from 0.5 to 30 atm for methaneair and from 0.5 to 25 atm for hydrogenair mixtures. The empirical equations for the burning velocities have been obtained. The obtained burning velocities were correlated by the Arrhenius form expression, which is based on the flame theory with a one-step kinetics, to yield the apparent order and activation energy of the overall reaction. The derived values were compared with those obtained by other investigators.
TL;DR: In this paper, the rates and products of the oxidations of phosphatidylcholines (PCs) in organic homogeneous solutions and as multilamellar liposomes in an aqueous dispersion were studied at 50 degrees C initiated by oil-soluble and water soluble azo compounds and with the aim primarily of elucidating the effect of substrate and reaction medium.