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We conducted uniaxial compression and grain growth experiments on fine‐grained (~1 μm) forsterite +20 vol% enstatite aggregates. Based on analyses of the sensitivity of the strain rate as a function of stress, we find power law creep at low stress, Newtonian creep at intermediate stress, and again power law creep at high stress, which correspond to interface‐controlled diffusion creep, grain boundary diffusion (Coble) creep, and a dislocation‐controlled process, respectively. The creep rate of these samples is well expressed by a combination of strain rates of these three mechanisms where interface‐controlled and Coble creep rates are combined as series‐sequential processes, while the rate of the dislocation process is added with them as a parallel‐concurrent process. Mechanical data collected continuously during the application of a constant load but while slowly changing temperature were decomposed into data for every 1 °C, which allowed consideration of >600 mechanical data points from 1054 to 1370 °C. The data were analyzed using Bayesian statistics implementing a Markov chain Monte Carlo method imposed on the above constitutive equation, resulting in the best fit flow law parameters for interface‐controlled and Coble creep. Samples were annealed for 500 hr at various temperatures. A comparison of the final grain sizes as a function of temperature on an Arrhenius plot resulted in an activation energy for grain growth similar to that observed for grain boundary diffusion during Coble creep of these materials. Power law, Newtonian, and again power law creep regimes are identified at low to high stress in forsterite + enstatite aggregateGreater than 600 creep data were analyzed by Bayesian statistics obtaining flow law parameters for interface‐controlled creep and Coble creepGrain growth rate as a function of temperature is well determined

Long‐period ground motions due to large earthquakes can cause devastating disasters, especially in urbanized areas located on sedimentary basins. To assess and mitigate such damage, it is essential to rapidly evaluate seismic hazards for infrastructures, which can be simulated by seismic response analyses that use waveforms at the base of each infrastructure as an input ground motion. The present study reconstructs the seismic wavefield in the Tokyo metropolitan area located on the Kanto sedimentary basin, Japan, from seismograms of the Metropolitan Seismic Observation network. The obtained wavefield fully explains the observed waveforms in the frequency band of 0.10–0.20 Hz. This is attributed to the seismic wavefield imaging technique proposed by Kano et al. (2017), which implements the replica exchange Monte Carlo method to simultaneously estimate model parameters related to the subsurface structure and source information. Further investigation shows that the reconstructed seismic wavefield lower than 0.30 Hz is of high quality in terms of variance reduction, which quantifies a misfit in waveforms but that the variance reduction rapidly worsens in higher frequencies. Meanwhile, the velocity response spectra show good agreement with observations up to 0.90 Hz in terms of the combined goodness of fit, which is a measure of misfit in the velocity response spectra. Inputting the reconstructed wavefield into seismic response analyses, we can rapidly assess the overall damage to infrastructures immediately after a large earthquake. Seismic wavefield >5 s in the Kanto basin is fully reconstructed from MeSO‐net seismograms using the replica exchange Monte Carlo methodThe estimated wavefield and velocity response spectra explain the observations in frequencies of <0.30 Hz and <0.90 Hz, respectivelySeismic wavefield imaging with dense observation networks will eventually assist real‐time assessments of large‐scale seismic hazards

The expansions of communities and cities over the last two decades have led to the increase of the number of health care facilities, and thus, clinical wastes are generated in significant amounts. Clinical wastes are a potential source for many pathogens such as viruses, parasites, fungi and bacteria. Therefore, clinical wastes should be treated before disposal into the environment. The incineration is the most common technology applied for the treatment process. However, the negative effects of incineration on humans and the environment have led scientists to define alternative technologies for the safe disposal of clinical waste. Numerous treatment technologies have been investigated as an alternative for incineration, such as autoclave and microwave. These technologies generally depend on temperature while the recent direction is to use a non-thermal sterilization processes. SC-CO2is one of the non-thermal sterilization technologies, which depends on pressure and low temperature. Currently, SC-CO2has been extensively used for the inactivation of microorganisms in food and pharmaceutical industries. However, the application of SC-CO2in treating clinical wastes has been on a rise. Studies conducted on the inactivation of fungi in food, normal saline and growth media indicate that SC-CO2has the ability to inactivate these organisms. In clinical wastes, SC-CO2has been found to be effective in the inactivation of pathogenic bacteria. Therefore, this review paper focuses on the potential of using SC-CO2as alternative technology for inactivating fungi in clinical wastes.

A new species of Kumanasamuhais described and illustrated from axenic single-spore isolates of Chorioactis geaster. The characteristics of conidia and hyphae are the same as the dematiaceous hyphomycete observed on decayed trunks of Quercusspp., where C. geasterappeared in the field in Japan. Our results indicated that C. geasterin situ colonizes decayed trunks of Quercusspp.

We use Bayesian modeling of the equation of state (EoS) to constrain the density (ρ) and Pwave velocity (VP) of liquid iron under conditions of Earth's outer core. Experiments at such high pressures (P) and temperatures (T) are technically challenging, so there are few data available to use in parameter optimization of the EoS. Our Bayesian inference modeling successfully estimates the posterior probability distribution of the parameters and unobserved data by using the Hamiltonian Monte Carlo method. These posterior probability distributions allow calculation of P‐ρand P‐VPprofiles of liquid iron along the adiabatic P‐Tprofile together with the associated credible intervals. Assuming that the temperature at the core‐mantle boundary (CMB) is 3,500–4,200 K, the P‐ρand P‐VPprofiles show deviations of ρand VPfrom the preliminary reference Earth model of about 8–11% and −3% to −5%, respectively. Deviations of the 95% credible intervals of the P‐ρprofile for the CMB and the inner core boundary are 6.9–9.7% and 6.5–9.8%, respectively. Equivalent deviations of the P‐VPprofile are −4.8% to −1.5% and −6.0% to −2.3%, respectively. Bayesian modeling of the EoS enables integration of small data sets that include unobserved data and evaluation of uncertainty ranges of physical properties, such as ρand VP, which are essential for comparison with seismological properties of the core. Earth's outer core is mainly composed a liquid iron that is essential in understanding Earth's internal structure. To characterize Earth's outer core, the relation between density, pressure, Pwave velocity, and temperature must be known. High‐pressure and high‐temperature compression experiments provide valuable data to estimate such relation. However, experiments at such high‐pressure and high‐temperature conditions are technically challenging, so it is difficult to collect an abundant data set covering a sufficiently broad range of pressure and temperature conditions. As it is necessary to estimate the relation using small data set, we performed statistical analysis based on the Bayesian inference that is one of the main probabilistic approaches to data analysis, and the analysis successfully conducted for the small data set. The result of analysis can constrain the pressure‐density and pressure‐Pwave velocity relation of the liquid iron under high‐pressure conditions corresponding to Earth's outer core together with associated uncertainties. We conclude that Bayesian inference is a powerful framework for analyzing small data sets from high‐pressure and high‐temperature experiments. Bayesian modeling of the equation of state for liquid iron is performed using data from three different compression experimentsParameters of the equation of state and unobserved data of the data set and their credible intervals (CIs) are estimatedPressure‐density and pressure‐Pwave velocity profiles and their CIs for liquid iron under outer‐core conditions are calculated Bayesian modeling of the equation of state for liquid iron is performed using data from three different compression experiments Parameters of the equation of state and unobserved data of the data set and their credible intervals (CIs) are estimated Pressure‐density and pressure‐Pwave velocity profiles and their CIs for liquid iron under outer‐core conditions are calculated

This study was designed to evaluate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with poly D, L lactic-co-glycolic acid (PLGA)/gelatin sponge complex (PGS) on the formation of bone in critically sized marginal defects of the mandible in dogs. Three months after extraction of the pre-molar teeth, rectangular bone defects (10×8×7 mm) were made in both sides of the mandible. A PGS block soaked in rhBMP-2 (400 µg/ml) was implanted into one defect (BMP (+) group). As control, an untreated PGS block was implanted into the contralateral defect (BMP (−) group). 2, 4, 8, and 12 weeks after implantation, the defects were examined. In the BMP (+) group, newly formed bone was found in all defects from 4 weeks onward and was marked at 12 weeks. In contrast, the BMP (−) group showed no appreciable new bone formation, even at 12 weeks. Moreover, density of newly formed bone in the BMP (+) group was similar to that of the surrounding cortical bone at 12 weeks. These findings suggest that rhBMP-2/PGS is an effective bone substitute for reconstructive surgery of the dog mandible. Copyright 2002 International Association of Oral and Maxillofacial Surgeons

Intramolecular proton transfer controlled by laser pulses was simulated. The motion of a proton in a molecule was treated by a one-dimensional, asymmetric double-well potential. To control the motion of a proton, a π-pulse approach, stimulated Raman adiabatic passage (STIRAP), and a chirping technique were applied to the system. In the π-pulse approach, the conditions of complete population inversion were determined for sequential and simultaneous irradiation of two laser fields. Similar population dynamics was obtained by a laser pulse sequence designed by global optimal control theory. The results obtained by using STIRAP and the single chirped laser pulse were compared with those obtained by using a π-pulse approach. It was found that a single negatively chirped laser pulse enables fast population transfer but maintains the robustness.

We have implemented ab initio linear combinations of Gaussian-type orbital calculations with generalized localized spin density approximation (GLSDA) for a dimer of equilateral H3 as a model of the noncollinear magnetic clusters. It has been found that the GLSDA solution with the three-dimensional noncollinear spin structure is, contrary to prior band calculations by other groups, the ground state near the Oh conformation. Further computational results are compared to that of ab initio generalized Hartree–Fock. The difference between them and the influence of the correlation correction were discussed. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001

It is difficult to consider the closed chain which contains odd-number spin sites under the UHF approximation because of the spin frustration. The generalized HF (GHF) method, which deals with generalized spin orbitals (GSO) of the form φ^αα+φ^ββ, can provide a characteristic electronic state with noncollinear spin configuration. In this article, explicit expressions of effective exchange integrals ( Jab values) based on GHF solutions were derived for the closed chain which contains odd-number spin sites. The Jab values were calculated for simple systems such as equilateral triangular H3, equilateral pentagonal H5, and so on. Furthermore, spin correlations and electron correlations of the H3 molecule are discussed by using visualization methods for electron correlations. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001

We propose an electronic structure calculation scheme for ground and low-lying excited states of molecular systems by using the generalized coherent state for fermion, where the coefficients of the coherent states are determined by a stochastic approach. This method has both the advantage of the ordinary quantum Monte Carlo and that of the direct diagonalization methods and does not suffer from the negative sign problem. We demonstrate a performance of the present method. © 2001 John Wiley & Sons, Inc. Int J Quant Chem, 2001

The quasiparticle energy of the H2 molecule is calculated by using the GW method, in which the self-energy operator fully depends on the frequency. The initial Green function G0 is constructed from the wave function obtained by the Hartree–Fock approximation (HFA) and local density approximation (LDA) in the framework of the density functional theory (DFT). From the results obtained we have shown that the wave function from the DFT–LDA is more effective than that from the HFA for G0. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 348–353, 2001

We proposed the ab initio linear combination of Gaussian type orbital (LCGTO) generalized spin orbital GW (GSO–GW) method and calculated triangular hydrogen molecules as models of the noncolinear magnetic clusters. A remarkable improvement of ionized potentials (IPs) by the GW procedure for GHFS solutions is observed in comparison with calculational results by full CI. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 369–374, 2001

We have proposed a numerical scheme for the non-Born–Oppenheimer density functional calculation based upon the Green function techniques within the GW approximation for evaluating quasiparticle excitations of the electronic and nuclear motion in the full quantum mechanical treatment. We calculate the excitation energy and the orbital energy of a hydrogen molecule, a muon molecule, and a positronium–hydrogen complex within the treatment of the dynamical screening. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 354–362, 2001

We investigated singly ordered phases of the charge density were (CDW), spin density wave (SDW), and singlet superconductivity (SSC) for a pseudo one-dimensional proton and electron transfer (PET) system of quinhydrone crystal by means of the two band model. We performed band structure calculations of model systems, which are (i) the quinone and the p-hydroquinone model and (ii) two semiquinones model. We found that the model (i) exhibits an insulator and the model (ii) exhibits the SDW insulator.

We investigate quantum spin dynamics of spin network systems in a liquid and in a molecular cluster with external magnetic field and discuss the importance of topological spin structures in relation to the quantum computing and quantum mechanical dimensions of the nuclear and the electron spins.

Previously, a method based on the two-electron density matrix (2-DM) has been used to obtain chemical interpretations with electron correlations. In the method, a 2-DM is expanded by its natural geminals. These natural geminals are visualized to obtain their chemical interpretations. An electronic state is understood as the set of geminals that have various correlations of two electrons. In this work, a extension of previous 2-DM-based method is described to compare two states of a system. In this method, the difference 2-DM between the two states is used instead of 2-DM itself. The applications of the method to trans-butadiene and trimethylene methane are shown. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001

AbstractWe developed the ab initioLinear Combination of Gaussian Type Orbital (LCGTO) program with generalized Hartree-Fock-Slater functional and calculate the hydrogen cluster as models of the noncollinear systems. Calculational results are compared with that of ab initioGHF and the difference between them are discussed.

Static polarizabilities and hyperpolarizabilities have been calculated for the furan homologues including furan (C4H4O), thiophene (C4H4S), selenophene (C4H4Se), and tellurophene (C4H4Te), at the Hartree−Fock and various correlation levels by ab initio molecular orbital methods. The influence of substitution with heavy atoms on the molecular properties of the homologues was examined theoretically. In the calculations for molecules with Se and Te atoms, the contribution of core electrons in the atoms was estimated using effective core potential (ECP) methods. With the calculation for the thiophene molecule, effectiveness of the use of the ECP method was examined, and the ECP method was found to give the (hyper)polarizability values similar to those obtained considering all electrons for the molecule. The calculated results show that substitution of the heteroatom with heavy atoms systematically increases the individual components of the polarizability, α, and second hyperpolarizability, γ. On the other hand, this does not give systematic variations on the first hyperpolarizability, β. The variation of these values depending on the homologues was examined in terms of the perturbation expansion formula and was explained by the energy levels of the electronic excited states in the valence states. The second hyperpolarizability values calculated, including electron correlation effect, are well correlated with the observed electronic components of nonlinear optical susceptibilities, χ⁽³⁾, obtained using optical Kerr effect experiments, which have been done in our laboratory. However, some discrepancy is observed between the theoretical and the experimental values for the homologues with heavier heteroatoms. Possible causes for the discrepancy are discussed in detail.

We applied our pictorial approach using the fundamental concept of the Hückel molecular orbital theory to the population inversion in the multilevel systems by the straddling-STIRAP (S-STIRAP). We showed that the mechanism of the population inversion in the multilevel system may be easily understood by our approach. It is also shown that our approach is useful to understand that the condition required for the laser frequency in the delayed pulse sequence is different for the even- and odd-level systems. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 80: 1068–1075, 2000

We investigate singly ordered phases of the charge density wave (CDW), spin density wave (SDW), and singlet superconductivity (SSC) for a pseudo one-dimensional proton and electron transfer (PET) system of the quinhydrone crystal by means of the two-band model. We perform band structure calculations of model systems, which are (i) the quinone and the p-hydroquinone model and (ii) the two semiquinones model. It is found that model (i) exhibits a nonmagnetic insulator and model (ii) manifests the SDW insulator at low temperature. Next, the conductive properties of model polymers including the deoxyribonucleic (DNA) base pairs (iii) A–T and (iv) G–C are investigated. We find that these model polymers also exhibit the SDW insulator, and the double-proton transfer reaction in the base pairs decreases the transition temperature, which is, however, much higher than room temperature. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 80: 882–891, 2000

A Hartree–Fock (HF) method dealing with general spin orbitals (GSO) of the form φ^αα+φ^ββ is called a generalized HF (GHF) method. This method can provide a characteristic electronic state with noncollinear spin configuration. Therefore, it is interesting to apply the method to spin-frustrated systems. In this study, we have developed ab initio GSO-based second-order Møller–Plesset (MP2), Tamm–Dancoff approximation (TDA), and random-phase approximation (RPA) methods. Further these methods, including GHF, were applied to the H3 molecule and obtained ground states and excited states of the molecule are discussed. The GSO-based MP2 method gave a similar energy surface to one of GHF. The GSO-based TDA and RPA methods found that excitations between the two states correspond to two different GHF solutions. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 80: 701–707, 2000

We developed the ab initio linear combination of Gaussian type orbital program with a generalized Hartree–Fock–Slater (GHFS) functional and calculated the four hydrogen clusters as models of the noncollinear magnetic clusters. We found that the GHFS solutions with the three-dimensional noncollinear spin structure is the ground state near the Td conformation. Computational results are compared with those of the ab initio generalized Hartree–Fock functional and the differences between them are discussed. Implications of the calculated results are discussed in relation to the electronic structures of Fe4S4 and Mn4O4 clusters. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 80: 664–671, 2000

Light‐dependent H2evolution did not occur in nitrogen‐deprived cultures of Rhodovulum sulfidophilumin the presence of ethanol. When ethanol was added to cells which had been grown with ammonia, derepression of the nitrogen fixation genes (nifHD) was inhibited at an ethanol concentration of 1 mM. On the other hand, when cells had nitrogenase‐catalyzed proton‐reducing activity prior to ethanol addition, reduction of the nifHDtranscript level did not occur after the addition. In cells grown with ammonia, concomitant addition of an auxiliary oxidant such as dimethylsulfoxide or sodium bicarbonate resulted in derepression of nitrogenase activity in the presence of ethanol. These results suggest that the electron‐accepting process is necessary for derepression of nifgenes in cultures which use ethanol as the electron donor.

Abstract.: As an extention of previous work [Yamaguchi K (1983) J Mol Structure (Theochem) 103:101], our theoretical efforts toward molecular materials are briefly reviewed. Axial, helical and general (cone, tetrahedron, etc) spin structures of carbon clusters, manganese oxide clusters and iron-sulfur clusters were investigated using the classical Heisenberg model and generalized Hartree-Fock theory. The spin flustrations in the clusters were also studied in relation to theoretical descriptions of the magnetism and the chemical bonds in active sites of several enzymes. The macroscopic quantum tunneling and coherence of spins in the manganese oxide clusters were analyzed using the instanton model, and the tunneling rate of spins was calculated by the coherent state path integral method. The spin transitions induced by an external magnetic field were studied by the path integral Monte Carlo method. The theoretical results were explained in terms of the symmetry and broken symmetry of the wavefunctions in the mesoscopic molecular systems, which are intermediate in the scale factor. The results were also applied to molecular design of mesoscopic clusters of clusters in the intermediate and strong correlation regime. The active control of spins is finally discussed from the viewpoint of functionalities in molecular and biological materials, and technological applications of mesoscopic molecular magnets are discussed with regard to quantum computing.

We have proposed a numerical scheme for the non–Born-Oppenheimer density functional calculation based upon the Green function techniques within the GW approximation for evaluating molecular properties in the full quantum mechanical treatment. We numerically calculate the physical properties of individual motion in the hydrogen molecule and the muon molecule by means of this method and discuss the isotope effect on the properties in relation to correlation effects. An applicability of the present method to cooperative electron–proton transfer(CEPT) systems is also discussed in comparison with the path-integral centroid methods. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 75: 875–883, 1999

Visualization methods of two-electron wave functions, electron–electron correlation plot, proposed previously are developed for magnetic molecules. This method can provide intuitive understanding of the two-body wave function and is a useful tool to compare characteristics of various approximation methods for many-body problems such as restricted Hartree–Fock (RHF), unrestricted Hartree–Fock (UHF), (GHF), and configuration interaction (CI). Our visualization method is fully explained on the basis of the two-body density matrix. Applications of these methods are performed for trans-butadiene and trimethylene methane, which are typical examples of nonmagnetic and magnetic organic molecules, respectively. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 75: 645–654, 1999

In our previous study [Int. J. Quant. Chem., to appear], we have developed a novel numerical calculation scheme for a dynamics of quantum network for linear molecular aggregates under intense time-dependent electric fields. In this approach, each molecule is assumed to be an electric dipole arranged linearly with an angle from the longitudinal axis, and the molecular interactions are taken into account by adding the radiations from these dipoles to the external electric fields. The effects of the radiations from all the dipoles involve the intermolecular distance, the speed of light, retarded polarization, and its first- and second-order time derivatives at the position of each dipole. The quantum dynamics is performed by solving coupled Liouville equations composed of the Liouville equation for each dipole. In the present study, we develop a calculation approach of nonperturbative second hyperpolarizability γ in our novel approach and examine the γ of dimer models composed of two-state molecules under the one-photon near resonant intense laser fields. Similar phase transition-like behavior in the field-intensity dependence of the γ is observed. We also investigate the second hyperpolarizability spectra in the three-photon resonant region for dimers composed of three-state molecules, which mimic the electronic states of allyl cation. Contrary to the one-photon resonant case, phase transition-like behavior is not observed in the intensity dependence of γ in the three-photon resonant region. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 71: 295–306, 1999

We investigated an interesting behavior in electron correlation and structure dependencies of the second hyperpolarizability (γ) of the ethylene model. The γ values of the ethylene model with plain and twisted structures were examined using various ab initio MO methods. γ was found to be largely changed depending on the rotation angle of the CH2 group in ethylene. The rotation-angle dependence of γ is remarkably different among Hartree–Fock and higher-order electron-correlation results. By applying hyperpolarizability density analysis, it was found that there are negative and positive contributions to γ and that, especially, σ electrons play an important role to determine the rotation-angle dependence of γ at high-order electron correlation levels. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 71: 177–183, 1999

Abstract: Electrical impedances were measured, at a range of frequencies from 2 to 200 kHz, in the lower limbs of nine patients with Duchenne muscular dystrophy and 12 normal subjects. The specific admittance was calculated from the impedance, based on the assumption that the shape of the part of the limb measured is a truncated cone. Curve-fitting to the admittance locus on the complex plane gave the intracellular and extracellular resistances and the membrane capacitance. The intracellular resistance was higher and the membrane capacitance was lower in the patients than in the normal subjects. The membrane capacitance in the normal subjects increased with age. In the patients, the membrane capacitance decreased, and the intracellular resistance increased with the stage of disability, which was assessed by a physician. These experimental results agree well with the theoretical explanation, which uses simplified spherical models to represent living tissue.