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The aim of this study was to investigate the changes in oxygen consumption during liver transplantation and to examine the relationship between intraoperatively elevated systemic oxygen consumption and postoperative liver function.This study was performed in 33 adult patients undergoing liver transplantation between September 2011 and March 2014. We measured intraoperative oxygen consumption through the use of indirect calorimetry, preoperative and intraoperative data, liver function tests, and postoperative complications and outcomes.The mean age of patients was 52 ± 9.7 years; 14 (42%) of them were women. Average Model for End-Stage Liver Disease scores were 20 ± 8.9. Oxygen consumption significantly increased after reperfusion from 172 ± 30 mL/min during the anhepatic phase to 209 ± 30 mL/min (P.0001). We divided patients into 2 groups according to the increase in oxygen consumption after reperfusion (oxygen consumption after reperfusion minus anhepatic phase oxygen consumption: 40 mL/min increase as cutoff). The higher consumption group had a longer cold ischemia time and higher postoperative aspartate aminotransferase and alanine aminotransferase levels as compared with the lower oxygen consumption group. There were no statistically significant differences in major postoperative complications, but the higher oxygen consumption group tended to have shorter hospital stays than the lower consumption group (58 versus 95 days).We have demonstrated that oxygen consumption significantly increased after reperfusion. Furthermore, this increased oxygen consumption was associated with a longer cold ischemia time and shorter hospital stays.

The perfect softening of the ferroelectric E u mode has been demonstrated in SrTi 18 O 3 by Raman scattering using a Sandercock-type tandem Fabry-Perot interferometer. The temperature dependence of the E u mode spectrum indicates that the mechanism of the ferroelectric phase transition is concluded as the ideal displacive type related to the Slater-type ferrlelectric mode. The observed result is compared to the previous reported results observed by a hyper-Raman scattering, inelastic neutron scattering, and Raman scattering.

The low frequency phonon mode in SrTi18O3 has been investigated by highresolution technique, in order to clarify the relationship between the perfect softening of the ferroelectric Eu mode and the acoustic anomaly in the c44 mode reported previously near the phase transition point Tc. The drastic softening and the anomalous increase of intensity were reported as the anomalous behavior of the c44 mode. However, in the present paper the anomaly of the c44 mode has not been observed in the spectra of SrTi18O3 with the 18O isotope concentration of 95%, though the perfect softening of the Eu mode has been confirmed clearly. The obtained result indicates that the anomalous behavior reported in the c44 mode is not intrinsic for the ferroelectric phase transition. The acoustic anomaly might be related to the ferroelectric phase transition through the coupling effects induced by a sample-depending internal stress originated in the structural phase transition at 105 K or the ferroelectric micro regions.

A mechanism of debris accumulation around the hole created on a silicon substrate with a femtosecond laser is experimentally studied. The hole created by the laser pulses has an edge consisting of pillared structures. However, no solid or liquid materials with similar dimensions as the pillared structures were ejected from the hole as the laser machining was performed in vacuum or in the presence of various gases. When the target was placed in a gas under 100 Torr, a thick layer of cotton-like material formed around the hole. Laser irradiation of a vertically placed target resulted in re-solidified material that formed after dripping from the hole edge, showing that substrate was partially melted. The surface morphology features suggest that the debris was formed as a result of aggregation of small particles such as atoms or atomic clusters on the substrate surface instead of large-scale droplets or fragments, which are commonly observed with nanosecond lasers.

A super radiation-resistant motor was developed for ITER, consisting of high radiation-durable organic insulation materials, such as poly(benzimidazole), poly-liquid-crystal (VECRUS/spl reg/, VECTRA/spl reg/), and poly(phenyl ether)/urea grease. The motor was subjected to irradiation tests carried out by /sup 60/Co /spl gamma/-ray at room temperature, and its radiation resistance was confirmed to be more than 100 MGy, which is 50 times of that of an ordinary radiation durable motor. The key factor for attaining high radiation resistance was the application of aluminum (Al) thin leaves (thickness: 0.2 /spl mu/m) mainly having faces. In a /sup 60/Co /spl gamma/-rays irradiation test conducted on VECRUS/spl reg/ paper containing Al leaves and overcoated by a silicon layer, an average absorption cross section for the Compton effect was found to decrease by 20% from the theoretical value calculated by the formula of Klein and Nishina. These results show that a secondary electron beam generated from a /spl gamma/-ray can easily pass through VECRUS/spl reg/ paper coated by a silicon layer including the dispersing Al leaf, by means of the channeling effect through the crystal lattice, thereby avoiding a close single collision and reducing serious damage.

Chemisorption of thiophene on a Si(0 0 1) surface has been studied by synchrotron radiation induced photoelectron spectroscopy (SRPES). Two adsorption-related components in Si 2p and S 2p spectra are observed after exposure of thiophene. It is suggested that the two components of Si 2p are ascribed to silicon bonded to hydrocarbon and sulfur. The core-level shift resolved photoelectron diffraction (PED) result indicates that the low-kinetic-energy component of S 2p can be ascribed to 2,5-dihydrothiophehe (DHT)-like species. Another S 2p component could be assigned to dissociated sulfur based on the results of PED and time evolution of the spectrum under irradiation. These assignments are consistent with the core-level shift of S 2p.

The hydrogen internal friction (HIF) has been measured for six multi-component metallic glasses. The HIF peak is quite broad with the peak temperature T p decreasing with increasing peak height, Q p −1 . Q p −1 versus T p relation is quite different among the alloys, suggesting a variety of hydrogen site energy distribution depending on the alloy composition. Considering the fact that two-level systems in metallic glasses for hydrogen jump are far from ideal, the observed relaxation strength is impossible to be interpreted in terms of a Snoek-type relaxation mechanism. A new hydrogen relaxation mechanism of a microscopic Gorsky effect has been proposed, where a large heterogeneity of elastic modulus in amorphous structure causes stress-induced hydrogen redistribution in a microscopic scale.

Seven multi-component metallic glasses of high glass forming ability (four Zr-based, a Mg-based, a Pd-based and a La-based glasses) have been hydrogenized electrolytically and internal friction has been measured at temperatures between 80 and 400 K. Hydrogen damping has been observed in every alloy; the internal friction peak is quite broad, where the peak value increases and then decreases and the peak temperature decreases with increasing hydrogen content. Compared with the results of the hydrogen damping in binary metallic glasses so far reported, the peak height versus peak temperature relation is generally shifted to higher temperature side in multi-component glasses, the origin of which has been discussed.

A photo-induced effect in the quantum dielectric system, such as SrTiO3, KTaO3, and CaTiO3, has been investigated under rather small external DC electric field. The dielectric measurement was performed under ultraviolet (UV) laser excitation combined with DC electric field. The gigantic photo-induced effects of dielectric properties of the quantum paraelectric systems have been firstly observed in the perovskite-type materials. The photoinduced dielectric effect was obtained as a function of DC electric field under constant UV irradiation.

Femtosecond time-domain observations of SrTi( 18 O x 16 O 1 m x ) 3 [STO18] in ferroelectric phase transition have been conducted by impulsive stimulated Raman scattering (ISRS). The phonon-polariton of A 1 -symmetry can be detected at the first time by the use of the heterodyne detection method with an optical phase mask. The static dielectric constant, which is calculated from the dispersion relation of the observed phonon-polariton, agrees well with the value reported in dielectric measurement. This fact indicates that the observed mode is the phonon-polariton originated from the coupling system between the ferroelectric soft mode and photon.

Recent results of a Brillouin scattering study on isotopically exchanged SrTi( 18 O 1 m x 16 O x ) are presented. Here we focus on the influence of isotopic substitution on the broad doublet in SrTi( 18 O 1 m x 16 O x ) and its behavior near the ferroelectric phase transition. Temperature dependence of the broad doublet is examined and compared with the results obtained for unsubstituted SrTi 16 O 3 crystal. The results are discussed in connection with the second-sound interpretation of the doublet origin.

The ferroelectric phase transition of the isotope 18 O exchanged strontium titanate SrTi 18 O 3 has been studied by both Brillouin- and Raman scattering near T m where the dielectric constant takes a maximum value. The Brillouin scattering study elucidates anomalous temperature dependence of the acoustic modes; the c 44 mode shows a drastic softening though the c 33 mode is almost independent of temperature. The Raman scattering study below T m shows a weak softening behavior of the ferroelectric mode. Existence of the ferroelectric micro-region is suggested in the isotopically induced ferroelectricity of SrTi 18 O 3 .

The isotopically induced ferroelectric phase transition of SrTi 18 O 3 , where 87% of oxygen atoms 16 O are exchanged for its isotope 18 O, has been studied by both Brillouin- and Raman scattering. On cooling run, at several degrees above the temperature where the dielectric constant takes a maximum value, the Brillouin spectrum of the c 44 mode in the paraelectric-tetragonal phase begins to split into two transverse acoustic modes. One of them shows a drastic softening with a dip on the spectrum characteristic for coupling with a central peak component. Though the ferroelectric soft A 2 u mode is Raman inactive in the paraelectric phase, it has been observed in the x ( yz )- x geometry indicating a local symmetry breaking. These anomalies suggest existence of a local distribution of the ferroelectric transition point caused by the ferroelectric micro-region.

Multiflorin A (1; kaempferol 3-O-β-D-(6-acetyl)-glucopyranosyl (1→4)-α-L-rhamnopyranoside), a kaempferol glycoside with an acetyl group in the sugar moiety, is the active principle of herbal medicines used for purging, such as the rose fruit (fruit of Rosa multiflora). In previous studies, we demonstrated that an acetyl group on the sugar moiety was responsible for the activity of 1and the active site of1 was the small intestine [1]. In the present study, we analyzed the purging related proteins of 1 in the small intestine mucosa by proteomic analysis. We repeated three purgative tests using 1 at intervals of ten days, and then selected three purgative-negative (PE-) mice that had no diarrhea in each test and three purgative-positive (PE+) mice that had diarrhea in each test. We then compared soluble protein profiles of the small intestine mucosae of both groups, and identified the differentially expressed proteins using 2-dimensional fluorescence difference gel electrophoresis (2D-DIGE) and LC-MS/MS spectrometry. As a result, we identified seven proteins showing increased expression by the PE+ mice and six proteins showing increased expression by the PE- mice. We focused on calreticulin that had increased in the PE+ mice, and demonstrated in vivo that activated expression of 1 involves an acetyl transfer reaction. Calreticulin is a major intercellular calcium-binding protein, which acts also as an acetyltransferase, catalyzing the transfer of the acetyl group to a functional receptor protein, such as nitric oxide synthase, which are activated by acetylation. Curcumin, a histone acetyltransferase inhibitor significantly inhibits the purging activity. Valproic acid, a histone deacetylase inhibitor significantly enhanced the purging activity. These results suggest that the active mechanism of 1 involves an acetyl transfer reaction to an unkown functional receptor protein. We are currently performing studies to determine the functional receptor protein. Keywords: Multiflorin A, purgative action, Rosa multiflora, small intestine, proteome analysis, calreticulin, acetyltransferase References: [1] Takagi S et al. On the Constituents of the Fruits of Rosa multiflora Thunb. II. Yakugaku Zasshi 1976; 96: 1217 – 1222.

It is shown that sp2 phase organization plays an important role in the field emission from nanostructured carbons. Emission is found to depend on the cluster size, anisotropy, and mesoscale bonding of the sp2 phase, and the electronic disorder. It is found by Raman spectroscopy that increasing the size of sp2 clusters in the 1–10 nm range improves emission. Anisotropy in the sp2 phase orientation can help or inhibit the emission. sp2 clusters embedded in the sp3 matrix or electronic disorder induced by localized defects oriented in the field direction can provide a local field enhancement to facilitate the emission.

Amino and other functional groups were introduced to a polyethylene substrate starting from the unsaturated pendant and bridge groups (collectively called side chains) of polyethylene, which had been prepared by γ-ray irradiation under an atmosphere of 1,3-butadiene of the polyethylene substrate (the drawn film of ultra-high- molecular-weight polyethylene, M¯v: 5 × 106). 2-Aminoethylamino groups were introduced to the side chains through treatment either with bromine or with peracetic acid vapor followed by immersion in ethylenediamine. Introduction of amino groups were confirmed by Fourier transform IR spectrometry, ninhydrin test, and acid–base titration. Starting from 2-aminoethylaminated polyethylene, modification cycles to grow a dendrimer on the film were applied; these consisted of 2-methoxycarbonylethylation and 2-aminoethylamidation. This technique resulted in hyperbranched modification of the polymer. The product is a kind of dendrimer grown on the surface of polyethylene film with amplified amino ends and has anion-exchange capacity and absorbs acid dye. Its application in practical uses is discussed.

Doppler broadened positron annihilation measurements were carried out using the positron beam technique on plasma treated polyethylene films as a function of incident positron energy. In addition, surface properties of the treated films also have been measured using other conventional techniques such as FT-IR, SEM and AFM. The surface tension of the films was also determined using sessile drop method. The S -parameter is seen to decrease on the surface upon plasma treatment that introduces polar groups such as hydroxyl and carbonyl on the surface. The results are discussed.

New high pressure and low temperature phases III, IV and V have been found for the zero-dimensional hydrogen-bonded crystal K3H (SO4)2by Raman scattering measurements. The pressure-temperature diagram was formed up to 32 GPa and down to 25 K for these three phases in addition to the ambient phase I and the phase II previously found.

The changes in the photoconductivity of hydrogenated tetrahedral amorphous carbon (ta-C:H) with nitrogen incorporation were studied. Low level nitrogen incorporation improves the photoconductivity, by shifting the Fermi level upwards in the band gap. Films with a photosensitivity of about 200 at room temperature under white light illumination of 35 mW/cm2 were obtained; thus is the highest value so far reported for diamond-like carbons. At high temperatures, photoconductivity is controlled by nonradiative recombination through gap states, whereas at low temperatures it occurs by energy-loss hopping in the band tails. Nitrogen addition does not create extra charge defect recombination centers. Low temperature photoconductivity allows the direct determination of the localization radius of the band tail states. This radius varies from 2–3 A in ta-C:H to 9 A in ta-C. This illustrates how hydrogen can increase state localization and the photoluminescence efficiency in amorphous carbons.

Ultra-high-molecular-weight polyethylene (M¯ v: 5 × 106, 100-times elongated film) was irradiated with γ-rays under a 1,3-butadiene atmosphere at room temperature. Electron paramagnetic resonance (EPR) measurements indicated that the radicals formed on the polyethylene substrate during the irradiation were short-lived. EPR, Fourier transform IR spectroscopy, solid-state NMR, and differential scanning calorimetry of the as-irradiated materials indicated that butadiene molecules were covalently bound to the polyethylene chains as pendant groups bearing trans-vinylene and vinyl functions in a ratio of 3:1. Some crosslinks among the pendants, or between pendants and the main chains were produced. The number of unsaturated pendants introduced (including bridges) per carbon atom of the polyethylene main chain was dependent on the irradiation dose and the butadiene pressure, and was 0.096 butadiene units for 10 kGy irradiation under a 304 kPa butadiene atmosphere. The unsaturated pendants or bridges on the polyethylene chain thus introduced may be good targets to functionalize polyethylene by covalent modification.

Synthetic andradite (Ca3Fe2Si3O12) has been compressed to loading pressures >21 GPa and heated to ∼1000°C by a YAG laser in a Diamond Anvil Cell (DAC). After quenching to room temperature, X-ray diffraction of the sample, still held at 21 GPa, showed that andradite had transformed to a cubic perovskite type polymorph with a = 3.460(4) Å. Upon decompression the perovskite phase transformed into an amorphous phase. The density of the perovskite polymorph (Ca3Fe2Si3O12) is ∼13.6% greater than that of isochemical andradite at 21 GPa. Ferric iron replaces Ca2+ and Si4+ in the perovskite structure (Fe3+ + Fe3+ = Si4+ + Ca2+), giving a formula unit: (Ca,Fe3+)(Si,Fe3+)O3. The new Fe3+-rich Ca-perovskite may provide new insight into the controls on the electrical conductivity of the lower mantle.

The ferroelectric soft modes of KDP (KH2PO4) and the 90% deuterated compound (K(H0.1D0.9)2PO4) have been excited coherently by impulsive stimulated Raman scattering. The observed time dependence of the excited modes shows a complete single exponential time decay after an electronic response at its time origin. The temperature dependence of the relaxation time τ of the modes shows clearly a critical slowing down in paraelectric phase, τ = τ 0 T 0 (T−T 0 ) , where T0 is the phase transition point of the clamped crystal. The isotope effect on τ is well confirmed as τ0 is 0.11×10−12s for KDP and τ0 is 0.82×10−12s for K(H0.1D0.9)2PO4.

A first-order phase transition induced by pressure was newly found at 2·88 GPa and 258 K. The transition temperature Tp shifts upward with increasing pressure at a rate of about 80 K/GPa. The linewidth of the v 2 mode does not show any broadening near Tp and its frequency in the low temperature phase is almost independent of temperature. These facts are well explained by the character of the strong first-order phase transition.

High-resolution Brillouin scattering measurements on a high-quality wurtzite gallium nitride (GaN) single crystal were carried out and elastic stiffness constants were determined. A comparison is given with the results of a recently reported model for calculation of the elastic constants of III-V semiconductors based on the modified version of Keyes's relations. A good agreement is found between the experimental and theoretical elastic constants for GaN.

To identify novel signal transducers involved in signaling mediated by the Src-family protein tyrosine kinases (PTKs), we used a yeast two-hybrid system with a probe corresponding to the regulatory region of p56lyn, a member of Src-family PTKs. One of the isolated clones contained the COOH-terminal 470 amino acid residues of p120c-cbl, the product of the cellular homologue of the v-cbl retroviral oncogene. p120c-cbl is a cytoplasmic protein with nuclear protein-like motifs. Here we show in vivo association of p120c-cbl with p53/56lyn. After stimulation of the B cell antigen receptor (BCR), p120c-cbl was rapidly tyrosine phosphorylated. Studies with lyn- or syk-negative chicken B cells demonstrated that p53/56lyn, but not p72syk, was crucial for tyrosine phosphorylation of p120c-cbl upon stimulation of the BCR. We also show the importance of p59fyn in tyrosine phosphorylation of p120c-cbl in the T-cell receptor-mediated signaling using fyn-overexpressing T cell hybridomas and splenic T cells from fyn-deficient mice. These results suggest that p120c-cbl is an important substrate of Src-family PTKs in the intracellular signaling mediated by the antigen receptors

Photoconductivity and photo-magneto-transport properties have been measured in quantum paraelectric SrTiO3 crystals. We have found a large isotope effect in the photocurrent value in this system. This isotope effect suggests an important contribution of the quantum fluctuations for the giant photoconductivity in the quantum paraelectric system.

In mixed crystal of K3H(SO4)2 and K3D(SO4)2, the internal modes of HSO4 −, DSO4 − and SO2− were separately observed. In the ordered phase, the splittings between ω(HSO4 −) and ω(SO2−), and ω(DSO4 −) and ω(SO2−) depend on temperature as (Tc − T)β with β = 0.25 ± 0.05. In the disordered state, HSO4 − and DSO4 − lines show broadening near the transition temperature. Motional narrowing theory developed in nuclear magnetic resonance is applied to analyse the broadening and the correlation time for hydrogen (deuteron) motion is obtained.

Detailed redox titrations monitored by EPR and UV-visible spectroscopies have been carried out on the dimeric ferredoxins I and II from Desulfovibrio vulgaris Miyazaki. Ferredoxin II contains a unique [4Fe-4S] cluster per subunit characterized by a midpoint potential of −417 mV at 24°C. The enthalpic and entropic contributions to the redox free energy variation of this cluster have been determined from the temperature dependence of the midpoint potential and compared to the data reported for other iron-sulfur proteins. The molecular arrangement of the two subunits is such that two [4Fe-4S] 1+ clusters are magnetically coupled in the fully reduced state of the protein. Ferredoxin I contains one [3Fe-4S] and one [4Fe-4S] cluster per subunit, whose spectral and redox properties are very similar to those of the same clusters in ferredoxin III from Desulfovibrio africanus . The strong heterogeneity in the redox properties of the [3Fe-4S] center supports a bridging position between the N-terminal and C-terminal parts of the protein.

The form of fluorine in Na2O-NaF-SiO2 slags has been investigated using Fourier transform infrared spectroscopy. Additions of NaF shifted absorption peaks for stretching modes of Si O bonds to higher wavenumbers, where the basicity of (mol-%Na2O)/ (mol-%SiO2 ) was kept constant, and the shift became larger with an increase in the concentration of NaF. This shift can be explained by the change from Si-O to Si-F bonds, with reference to harmonic oscillation theory of diatomic molecules. It is likely that added NaF depolymerises the silicate network to form Si-F bonds in Na2O-NaF-SiO2 slags.

The Hall coefficient, the resistivity, and the superconducting transition temperature have been measured for teteragonal CaLaBaCu3Oy in a range of oxygen content 6.6

The involvement of Ca2+ in the mechanism of the purgative action of rhein anthrone was studied. Among individual or combination pretreatments with calcium channel blockers, calmodulin antagonists and prostaglandin biosynthesis inhibitors, the combination of indomethacin and nifedipine completely blocked the diarrhoea induced by rhein anthrone and also inhibited its effects on colonic fluid and electrolyte transport, and large intestinal motility. Calmodulin antagonists were less active regarding suppression of the effects of rhein anthrone. We concluded that, in addition to prostaglandins, diarrhoea induced by rhein anthrone must also involve the calcium channel which can be blocked by nifedipine, but not verapamil.

Elastic ‘breather’ paints, permeable to moisture vapor, have been formulated with low Tg latex polymers, utilizing microgels produced via an emulsion polymerization process. These microgels were designed to have a hydrophilic sheath surrounding a crosslinked acrylic core. The moisture vapor transmission rates of the films were measured and showed a 10-fold increase when the microgel was included in the formulation, with no sacrifice of either the water-resistance property or the carbon dioxide gas barrier performance. Low molecular weight surfactants were tried as an alternative to the microgels, but failed to attain the improved permeation performance. TEM observation demonstrates that the microgels segregate within the interfacial space between the coalescing latex particles, forming a fine percolating texture. The mechanism for moisture vapor permeation through the films which contain microgels is discussed in more detail.

Technical challenges in applying the chemical absorption process to CO 2 recovery from power plant flue gas are described and measures for improvement, including energy saving measures are introduced.

The relationship between the aspartate aminotransferase (AST) activation coefficient and the intracellular in situ proportion of the pyridoxal 5′-phosphate (PLP) form of AST (PLP-AST) in total AST was determined. Erythrocytes from Japanese-White strain rabbits had an activation coefficient of 1.85. This indicated that 54.1% of the AST in the hemolysates from these erythrocytes was the holoenzyme. Sodium borohydride reduction showed that 64.8% of the total erythrocyte AST was present as the PLP-AST holoenzyme. Increases in intracellular PLP and pyridoxamine 5′-phosphate (PMP) concentrations, generated by preincubation of the erythrocytes with pyridoxal (PL) and pyridoxamine (PM), significantly decreased the values of the activation coefficient. However, these increases did not significantly increase the intracellular proportion of PLP-AST in total AST. These results showed that the AST activation coefficient reflects the saturation level of AST in the hemolysate rather than the intracellular in situ level of the holo-form of AST (holoAST). Thus, establishment of standard conditions is required for use of the activation coefficient, which is inherently a valuable biochemical marker of the vitamin B-6 status, for accurate deduction of the nutritional status of vitamin B-6 in test organisms.

Measurements of superconducting transition temperature T c and lattice parameters of CaLaBaCu 3 O y (CLBCO) indicate that CLBCO is a tetragonal bulk superconductor in the oxygen-content range from y =6.7 to 7. The T c decreases monotonously with decreasing oxygen content and no superconducting transition is observed below y =6.7. It is concluded that disappearance of the superconductivity for y y

High-resolution Brillouin scattering experiments have been performed for a high-quality free-standing gallium nitride (GaN) substrate. Elastic stiffness constants are reported. A comparison is made with the results of an earlier study for a GaN thin film on sapphire substrate.

The ν2 mode of SO42− ions in the zero-dimensional hydrogen-bonded crystals Rb3DxH1−x(SO4)2 (x=0.20,0.88) and K3DxH1−x(SO4)2 (x=0.45) are observed by Raman scattering. For each crystal, the ν2 line width shows anomalous broadening near Tc in the disordered phase. The inverse of the line width corresponds to a mean characteristic time of the flip–flop motions of a hydrogen and a deuterium. It is found that the gradient of the temperature-τc−1 curve is small below around 55 K compared with that above 55 K. This fact suggests that some quantum mechanical process like zero-point vibration or tunneling influences on the flip–flop motions below around 55 K.

Raman scattering spectra of the ferroelectric KDP (KH2PO4) have been observed under hydrostatic pressure up to 52.0 kbar using a diamond anvil cell at room temperature. A curious dispersion relation of the soft mode at the Γ point of the Brillouin zone is derived from the low-frequency components of the B2(z) spectra in z(yx)z + δ and x(yx)y geometries after numerical fitting based on the coupled phonon model. The dispersion relation suggests breakdown of the soft-mode model of KDP. Each of the frequencies of the internal v1, v2 and v3 modes of the PO4 ion show a linear dependence on pressure with the mode Gruneisen parameter, 0.32, 0.31 and a small value of 2.5 × 10−2, respectively. Increase of the frequencies of the v1 and v2 modes corresponds to pressure dependence of the P–O distance. A new pressure-induced phase transition appears at 40.0 kbar with a growing relaxational central peak in the spectra.

We successfully fabricated high-quality InAlN/GaN heterostructures for high electron mobility transistors (HEMTs) on Si (111) substrate by metalorganic chemical vapor deposition (MOCVD). X-ray diffraction measurements revealed that InAlN/GaN heterostructures grown under optimal conditions have a flat surface and an abrupt heterointerface. The surface roughness evaluated from atomic force microscopy (AFM) is improved, compared with previous reports. Electron mobility of about 1,200 and over 1,800 cm2/V·s are obtained for InAlN/GaN heterostructures without and with an AlN interlayer, respectively. These mobility values are the highest ones ever reported for InAlN/GaN heterostructures grown on Si substrates.

The ${E}_{u}$ mode of the isotope-induced ferroelectric strontium titanate ${\mathrm{SrTi}}^{18}{\mathrm{O}}_{3}$ shows a perfect softening at the ferroelectric phase transition temperature ${T}_{c}$, where the frequency of the underdamped mode approaches completely to zero within the instrumental resolution. The spectra of the Raman inactive soft ${E}_{u}$ mode have been successfully observed owing to local symmetry breaking and by long-term accumulation of the spectral intensity with a high resolution technique. The mechanism of the phase transition is concluded to be an ideal displacive-type accompanied with perfect softening of the Slater-type polar ${E}_{u}$ mode. The difference between the soft mode behavior of $\mathrm{SrTi}^{16}\mathrm{O}_{3}$ and $\mathrm{SrTi}^{18}\mathrm{O}_{3}$ indicates that the origin of the quantum paraelectric state of $\mathrm{SrTi}^{16}\mathrm{O}_{3}$ lies in the quantum fluctuation of the oxide octahedron in the perovskite structure.

By means of femtosecond optically heterodyne-detected optical Kerr effect and polarization-selective impulsive stimulated light scattering techniques, we have directly observed the fluctuation and low-frequency phonon structures in disordered systems over a wide frequency range. Various disordered materials such as liquid, polymer and glass are chosen for the sample and their characteristics are discussed.

The successive phase transitions at T 0 (222 K) and T C (74 K) of hexagonal BaTiO 3 have been studied by Brillouin scattering. An intense central peak was found near T 0 and was identified as a result of scattering from the coupled soft optic and acoustic mode. The coupled mode model was employed in order to explain the observed spectral changes. The ω 0 2 Γ 0 ratio of the soft optic mode frequency ω 0 and the damping constant Γ 0 , and the square of bilinear coupling constant A show linear dependence on temperature difference T − T 0 , indicating the mean field behavior. The clear softening of c 66 shear acoustic mode was found near T C . The square of frequency of c 66 mode depends linearly on T − T C around the transition temperature. The results conclusively show that the phase transition at T C is the proper ferroelastic transition with the order parameter strain s 6 .

A silicon retina was fabricated to emulate two fundamental types of response in the vertebrate retinal circuit, namely the sustained and transient responses. The sustained response exhibits a Laplacian-Gaussian-like receptive field. The transient response is obtained by subtracting consecutive image frames. The chip was applied for the extraction of motion direction in real-time under indoor illumination.

Ethylene-propylene rubber (EP rubber), as cable insulating material used in Japanese domestic nuclear power plants, is exposed to /spl gamma/-rays, and aged in an oxygen atmosphere. Oxygen consumption and CO/sub 2/ evolution during /spl gamma/-radiation and thermal aging are measured by gas chromatography. Elongation at the break of aged EP rubber is found to be related to oxygen consumption and CO/sub 2/ evolution during the degradation, and is scarcely affected by radiation dose and temperature. These O/sub 2/ and CO/sub 2/ measurements may be useful to estimate quantitatively the degree of polymer degradation.

A silicon retina was fabricated to emulate two fundamental types of response in the vertebrate retinal circuit, i.e. the sustained response and the transient response. The outputs of the silicon retina emulating the sustained response exhibit a Laplacian-Gaussian-like receptive field and therefore carry out a smoothing and contrast enhancement on input images. The outputs emulating the transient response were obtained by subtracting subsequent images that were smoothed by a resistive network and therefore are sensitive to moving object. The chip was applied for a real time image processing in indoor illumination.