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Spontaneous intracranial hypotension (SIH) is secondary to a cerebrospinal fluid leak at the spinal level without obvious causative events. Several signs on brain and cervical spine magnetic resonance (MR) imaging (MRI) have been associated with SIH but can be equivocal or negative. This retrospective study sought to identify characteristic SIH signs on thoracic spinal MRI. Cranial and spinal MR images of 27 consecutive patients with classic SIH symptoms, who eventually received epidural autologous blood patches (EBPs), were analyzed. The most prevalent findings on T2-weighted MRI at the thoracic level were anterior shift of the spinal cord (96.3%) and dorsal dura mater (81.5%), probably caused by dural sac shrinkage. These dural sac shrinkage signs (DSSS) were frequently accompanied by cerebrospinal fluid collection in the posterior epidural space (77.8%) and a prominent epidural venous plexus (77.8%). These findings disappeared in all six patients who underwent post-EBP spinal MRI. Dural enhancement and brain sagging were minimum or absent on the cranial MR images of seven patients, although DSSS were obvious in these seven patients. For 23 patients with SIH and 28 healthy volunteers, a diagnostic test using thoracic MRI was performed by 13 experts to validate the usefulness of DSSS. The median sensitivity, specificity, positive-predictive value, negative-predictive value, and accuracy of the DSSS were high (range, 0.913–0.931). Detection of DSSS on thoracic MRI facilitates an SIH diagnosis without the use of invasive imaging modalities. The DSSS were positive even in patients in whom classic cranial MRI signs for SIH were equivocal or minimal.

This study aimed to determine the prevalence and risk factors for brain white matter changes in normal young and middle-aged participants who underwent Brain Dock (brain screening). We analyzed 5,000 consecutive healthy participants from the Brain Dock registry between August to December 2018. Age, sex, body mass index (BMI), medical history, deep subcortical white matter high intensity (DSWMH), periventricular high intensity (PVH), and enlargement of perivascular space (EPVS) were investigated in relation to age. The prevalence of DSWMH, PVH, and EPVS were 35.3%, 14.0%, and 17.8%, respectively. Multivariate logistic regression analyses for brain white matter changes were conducted. The significant risk factors in participants aged < 50 years were: age (OR:1.09, 95% CI:1.07-1.12), the female sex (1.29, 1.03-1.60), BMI obesity (1.86, 1.12-3.08), and hypertension (1.67, 1.18-2.35) for DSWMH; age (1.08, 1.04-1.13) and the female sex (1.56, 1.03-2.36) for PVH; and age (1.07, 1.05–1.10) and the female sex (0.77, 0.60-1.00) for EPVS. In conclusion, age was consistently identified as a significant risk factor in young and middle-aged participants. Some risk factors for brain white matter changes were identified even in young and middle-aged participants in this study. Further longitudinal studies should be done in the future.

Transparent low-melting inorganic glass is an attractive industrial material based on its high thermal and light resistance compared with conventional engineering plastics. If the melting temperature of inorganic glass could be decreased, the doping of guest materials or compression moulding on the glass surface would be easier. Although phosphate glass is considered as a potential candidate because of its transparency in the visible region and low-melting behaviour, water durability often becomes a problem for implementation. Here, we prepared inorganic low-melting phosphate glass at a temperature of 500 °C via a melting and quenching methodology. It was found that tin-doped phosphate glasses exhibited higher thermal and light resistance properties than polycarbonates. Colourless transparent oxide glasses without organic components are capable of bringing about new possibilities for the application of inorganic glasses.

Despite an increase in CT studies to evaluate patients with coronavirus disease 2019 (COVID-19), their indication in triage is not well-established. The purpose was to investigate the incidence of lung involvement and analyzed factors related to lung involvement on CT images for establishment of the indication for CT scans in the triaging of COVID-19 patients.Included were 192 COVID-19 patients who had undergone CT scans and blood tests for triaging. Two radiologists reviewed the CT images and recorded the incidence of lung involvement. The prediction model for lung involvement on CT images using clinico-laboratory variables [age, gender, body mass index, oxygen saturation of the peripheral artery (SpOIn 120 of the 192 patients (62.5%), CT revealed lung involvement. The patient age (odds ratio [OR]; 4.95, 95% confidence interval [CI]; 0.93-26.49), albumin (OR; 4.66, 95%CI; 1.37-15.84), lactate dehydrogenase (OR; 5.79, 95%CI; 1.43-23.38) and C-reactive protein (OR; 8.93, 95%CI; 4.13-19.29) were selected for the final prediction model for lung involvement on CT images. The cross-validated area under the receiver operating characteristics (ROC) curve was 0.83.The high incidence of lung involvement (62.5%) was confirmed on CT images. The proposed prediction model that includes the patient age, albumin, lactate dehydrogenase, and C-reactive protein may be useful for predicting lung involvement on CT images and may assist in deciding whether triaged COVID-19 patients should undergo CT.

A viscoelastic study of the 25GeS2-55SbS3/2-20SnS and 12.5GaS3/2-75SbS3/2–12.5SnS sulfide glasses was carried out around their deformation temperatures using a uniaxial compression creep test. Their viscosities showed similar temperature dependences, but slightly lower sensitivity was observed for the latter glass than for the former glass, which may be explained by the theory of free volume. The creep function, derived from the displacement of the height of the sample subjected to a creep test, was converted into relaxation moduli by performing a Laplace transformation and its inversion. The shear relaxation moduli G(t) revealed two distinct structural relaxation processes, specifically with short and long relaxation times. Both the major fast-relaxation process and minor slow-relaxation process obeyed the time–temperature superposition principle. The fast-relaxation activation energies for both glasses were estimated to be about 390 kJ/mol. This value was close to the dissociation energy of the Sb—S bond, which formed the major cross-links of the glass network. In contrast, slow-relaxation activation energies of approximately 590 and 550 kJ/mol were determined for the GeS2-containing and GaS3/2-containing glasses, respectively. The slow-relaxation process, having a higher activation energy for the GeS2-containing glass than for the GaS3/2-containing glass, was concluded to have involved dissociation and recombination, even at high temperatures, of the stronger crosslinks made of the Ge—S and Ga—S bonds in the glass network.

The viscoelastic behavior of alkali and alkaline earth aluminophosphate glasses was studied. The energetic interpretation was based on the Arrhenius behavior of the relaxation modulus. With increasing aluminum content, the activation energy of the relaxation increased in the alkali series but decreased in the alkaline earth series. Dynamic viscoelasticity measurements revealed that the loss modulus, E”(ω), showed a crossover of the relaxation process at the glass transition temperatures. The activation energy below the transition temperature was close to the energies of internal friction or ionic self-diffusion. The energy above the transition temperature corresponded to the dissociation energies of alkali-oxygen or alkaline earth-oxygen single bonds. The different behavior in the energy of the relaxation modulus between alkali and alkaline earth series was due to weak bonds caused by adding alkali ions and the formation of crosslinking by low-coordinate aluminum polyhedra because of the presence of alkaline earth ions.

Spontaneous intracranial hypotension (SIH) is secondary to a cerebrospinal fluid leak at the spinal level without obvious causative events. Several signs on brain and cervical spine magnetic resonance (MR) imaging (MRI) have been associated with SIH but can be equivocal or negative. This retrospective study sought to identify characteristic SIH signs on thoracic spinal MRI.Cranial and spinal MR images of 27 consecutive patients with classic SIH symptoms, who eventually received epidural autologous blood patches (EBPs), were analyzed.The most prevalent findings on T2-weighted MRI at the thoracic level were anterior shift of the spinal cord (96.3%) and dorsal dura mater (81.5%), probably caused by dural sac shrinkage. These dural sac shrinkage signs (DSSS) were frequently accompanied by cerebrospinal fluid collection in the posterior epidural space (77.8%) and a prominent epidural venous plexus (77.8%). These findings disappeared in all six patients who underwent post-EBP spinal MRI. Dural enhancement and brain sagging were minimum or absent on the cranial MR images of seven patients, although DSSS were obvious in these seven patients. For 23 patients with SIH and 28 healthy volunteers, a diagnostic test using thoracic MRI was performed by 13 experts to validate the usefulness of DSSS. The median sensitivity, specificity, positive-predictive value, negative-predictive value, and accuracy of the DSSS were high (range, 0.913-0.931).Detection of DSSS on thoracic MRI facilitates an SIH diagnosis without the use of invasive imaging modalities. The DSSS were positive even in patients in whom classic cranial MRI signs for SIH were equivocal or minimal.

Transparent low-melting inorganic glass is an attractive industrial material based on its high thermal and light resistance compared with conventional engineering plastics. If the melting temperature of inorganic glass could be decreased, the doping of guest materials or compression moulding on the glass surface would be easier. Although phosphate glass is considered as a potential candidate because of its transparency in the visible region and low-melting behaviour, water durability often becomes a problem for implementation. Here, we prepared inorganic low-melting phosphate glass at a temperature of 500 °C via a melting and quenching methodology. It was found that tin-doped phosphate glasses exhibited higher thermal and light resistance properties than polycarbonates. Colourless transparent oxide glasses without organic components are capable of bringing about new possibilities for the application of inorganic glasses.

Chalcogenide glasses have attracted a great deal of attention for the optical elements of infrared devices. The viscosity and elasticity of glasses are important characteristics for the use of precision molding techniques. The uniaxial compression creep behavior of Ge20Sb15Se65 glass was studied around its deformation temperature. The derived creep function was converted into relaxation moduli by Laplace transformation and its inversion. Analysis using a two-term Maxwell model revealed the shear relaxation modulus G(t) as two distinct structural relaxation processes with short and long relaxation times on the order of 101 s and 103 s, respectively, at 313 °C. The fast relaxation with high elasticity obeyed the time–temperature superposition principle and its activation energy ΔH1 was estimated to be 350 ± 10 kJ/mol using Narayanaswamy's relation. This energy is mainly comparable to the bond dissociation energies of Se Se (~320 kJ/mol). The process was therefore suggested to be due to motion around these thermally broken inter-atomic bonds, as in many glassy systems. In contrast, the low-elasticity slow relaxation process had activation energy of approximately 480 ± 60 kJ/mol and was considered to represent breaking and rearrangement of heteronuclear Ge Se and Sb Se bonds in the glass network during pressure-induced entanglement.

In addition to the total attenuation of ionizing radiation, photoluminescence has been conventionally recognized to affect radiation-induced luminescence. In this study, we examined the optical and luminescence properties of Ce3+ in lithium silicate-based glasses with different optical basicities. The existence of Ce4+ was confirmed based on the optical absorption, Ce L3-edge X-ray absorption near edge structure (XANES), and optical coefficients of the calculated Ce4+ using the optical absorption and XANES data of Ce4+ species from a previous report. Compared to other multicomponent glasses, there was a slight deviation in the decay constant and quantum yield (QY) of the stoichiometric Li2O–2SiO2 glass. In addition, the light yields calculated from the pulse height spectra with 252Cf irradiation depend on the QY of the glasses. Considering the energy conversion process, the dependence of the light yield agreed with that of the conventional energy conversion process of neutron-induced luminescence.

The macroscopic elastic modulus of a solid-state matter is generally affected by the packing density and average bond strength of the constituent atoms. However, because of the diversity of network connections in oxide glasses, an understanding based on the network structure is also required for precise structural categorisation. Here, we examine the relationship between the elastic modulus and structural parameters, viz., the correlation length of the Boson peak and cavity size calculated from the positron annihilation measurement, of BaO-TiO2-GeO2-SiO2 glasses. The Poisson's ratio correlates with the ratio of the longitudinal and transversal sound velocities, and thermal stability parameter ΔT. The Boson peak frequencies of these glasses at the GeO2-rich region exhibit an apparent plateau behavior, indicating that the rate of change in the sound velocity is similar to that in the correlation length. Although the numerical calculation of the cavity in this glass by positron annihilation spectroscopy is unavailable because of the d -electron of Ti cations, the τ1 value shows a similar compositional dependence as the correlation length of the Boson peak. It is expected that a combination of elastic modulus and inelastic light scattering of glasses will be helpful in understanding glass-forming melts.

OBJECTIVE To assess the clinical benefits of magnetic resonance imaging/transrectal ultrasound fusion-targeted biopsy for biopsy-naive Japanese men. METHODS Between February 2017 and August 2018, 131 biopsy-naive men who underwent targeted biopsy together with 10-core systematic biopsy at Hiroshima University Hospital were retrospectively investigated. Multiparametric magnetic resonance imaging findings were reported based on Prostate Imaging Reporting and Data System version 2. RESULTS The overall cancer detection rates per patient were 69.5% in systematic biopsy + targeted biopsy cores, 61.1% in systematic biopsy cores and 61.1% in targeted biopsy cores. The detection rates for clinically significant prostate cancer were 43.5% in targeted biopsy cores and 35.9% in systematic biopsy cores (P = 0.04), whereas the detection rates for clinically insignificant prostate cancer were 17.6% and 25.2% respectively (P = 0.04). Lesions in the peripheral zone were diagnosed more with clinically significant prostate cancer (54.8% vs 20.7%, P

Rationale: Computer-assisted detection (CAD) systems based on artificial intelligence (AI) using convolutional neural network (CNN) have been successfully used for the diagnosis of unruptured cerebral aneurysms in experimental situations. However, it is yet unclear whether CAD systems can detect cerebral aneurysms effectively in real-life clinical situations. This paper describes the diagnostic efficacy of CAD systems for cerebral aneurysms and the types of cerebral aneurysms that they can detect. Patient Concerns: From March 7, 2017 to August 26, 2018 we performed brain magnetic resonance imaging (MRI) scans for 1623 subjects, to rule out intracranial diseases. We retrospectively reviewed the medical records including the history and images for each patient. Diagnoses, interventions and outcomes: Among them, we encountered 5 cases in whom the cerebral aneurysms had been overlooked in the first and second round of imaging, and were detected for the first time by CAD. All missed aneurysms were less than 2 mm in diameter. Of the 5 aneurysms, 2 were internal carotid artery (ICA) paraclinoid aneurysms, 2 were Internal carotid-posterior communicating artery (IC-PC) aneurysms and 1 was a distal middle cerebral artery (MCA) aneurysm. Lessons: Our CAD system can detect very small aneurysms masked by the surrounding arteries and difficult for radiologists to detect. In the future, CAD systems might pave the way to substitute the workload of diagnostic radiologists and reduce the cost of human labor.

Under the assumption that neurovascular compression can be caused by elongation or kinking of the artery, we measured the length of each section of the vertebrobasilar artery, compared the lengths between various age groups, and evaluated the involvement of the arterial sections in brain stem compression in 1000 cases. The lengths of the posterior inferior cerebellar artery (PICA)-union of both vertebral arteries (union), union-anterior inferior cerebellar artery (AICA), AICA-superior cerebellar artery (SCA), and union- superior cerebellar artery were measured using an arterial length measuring tool applied to three-dimensional images. The presence of arterial compression of the brain stem was also evaluated. The mean age of the participants was 66.8 ± 12.9 years, and 44.8% were men. Intraclass correlation coefficients for both inter-rater reliability and intra-rater reliability were high in all sections. The vessel lengths of left AICA-SCA (P 0.001), left union-SCA (P 0.0001), left PICA-union (P = 0.03), right AICA-SCA (P = 0.002), right union-SCA (P 0.0001), and right PICA-union (P = 0.04) increased with age, but each R

We have examined the X-ray-induced luminescence of Sn-doped zinc borate (SZB) glasses prepared by a conventional melt-quenching method in an Ar atmosphere, determining that there is a linear relationship between the thermal properties and SnO, in addition to the elastic properties. The scintillation intensity of SZB glasses increases with tin concentration. Meanwhile, the intensity of thermally stimulated luminescence (TSL) achieves a maximum peak area in the sample with 0.1 mol% Sn concentration. A clear inverse relationship between scintillation and TSL in SZB glasses is observed.

A procedure for determining the crystal system of a microcrystalline powder is described. In this procedure, in situ X-ray diffraction measurements are performed on a microcrystal suspension oriented uniaxially under static and rotating magnetic fields. This is followed by the classification of the obtained diffraction images using a flowchart proposed in this study. To demonstrate the validity of this procedure, diffraction images were recorded for microcrystalline suspensions prepared from known crystal systems including triclinic (d-arabitol), monoclinic (cellobiose), orthorhombic (l-alanine), tetragonal (urea), trigonal (bismuth, calcite), hexagonal (zinc), and cubic (sodium chloride) systems. The crystals were classified into their respective crystal systems following the proposed procedure. The determined crystal systems for biaxial crystals were consistent with the reported crystal systems of the microcrystalline powders investigated. Herein, determination of the lattice parameters and space groups...

A face centered cubic (FCC) type Mg–Sc hydride (Mg0.8Sc0.2Hx phase) was prepared by an ultra-high pressure (UHP) technique generating an 8 GPa hydrogen pressure. Reversible hydrogen releasing and restoring behaviors have been observed by a differential scanning calorimeter (DSC) measurement at a 0.5 MPa hydrogen pressure. The hydrogen releasing temperature was lower by around 70 K than that of MgH2. The structural analysis using a Rietveld refinement of the synchrotron X-ray diffraction patterns indicated that the FCC phase was preserved without decomposition after the reproducible hydrogen releasing and restoring reactions.

ZnF2 thin films were deposited on SiO2-glass and Al2O3-single crystal substrates using electron-beam evaporation, and the morphology of the films was studied in relation to the kind of substrate and deposition conditions. While the films deposited on SiO2-glass, (11 2 ¯ 0)-Al2O3 substrates exhibited an almost non-oriented polycrystalline nature, the films deposited on (0001)-Al2O3 substrates were epitaxially grown (100)-oriented films. The full-width at half maximum of the rocking curve of (200)-diffraction for the (100)-oriented film deposited at 400 °C was 150″. This value was comparatively small compared with previously reported (100)-oriented SnO2 and TiO2 films and showed the high orientation and crystallinity of the ZnF2 film. From the transmission spectra from near-infrared (NIR) to vacuum ultraviolet (VUV), the optical band gap of the ZnF2 was evaluated to be 6.7 eV, and the films exhibited high transparency in the wide range from NIR to VUV. We discuss the potential of the film as a transparent conducting material in the VUV region.

The effects of the substitution of fluoride ions for oxide ions on the thermal and optical properties of ternary ZnO-Bi 2 O 3 -P 2 O 5 glass with low-P 2 O 5 content (20–25 mol%) were investigated. Fluoride ions were introduced into the glass up to about 12 mol% as ZnF 2 . Raman spectra indicated that fluoride ions were substituted for oxide ions connected with bismuth ions. Deformation and glass transition temperatures decreased monotonically with fluorine concentration. The absorption edge shifted toward higher energies with increasing fluorine concentration by about 0.3 eV for 12 mol% ZnF 2 substitution. The blue shift of the absorption edge is attributable to two effects. One was a blue shift of an absorption band which was observed as a peak at 4.7 eV in the reflection spectra and was attributed to the spin forbidden 6s–6p interband transition in Bi 3+ ions. The blue shift originates from a change in electron-donating ability through anions as expected from electronegativity or optical basicity. Another is a disappearance of a shoulder at around 4.3 eV in the reflection spectra. The latter was the major reason for the large blue shift of the absorption edge energy, because the band relating to the 4.3 eV shoulder is close to the absorption edge.

Carbon/silica composite films were prepared from colloidal silica aqueous solution in which vapour grown carbon nano-fibers were dispersed. The orientation of nano-fibers was attempted by dip-coating substrates under high magnetic field up to 10 T. The fibers started to align along the direction of magnetic field below 1 T. The degree of orientation was saturated at about 6 T. The anisotropic susceptibility, Δχ = χ// − χb, was estimated to be (3.05 ± 1.10) × 10−7 cm3/mol from the fitting of numerical simulation. Optical anisotropy, the ratio between transmittances of light polarized perpendicular to and parallel to the direction of fiber orientation, increased immediately in the films prepared under applied fields below 1 T and almost saturated above 1 T. The optical anisotropy was in good agreement with the behaviour of magnetic orientation of fibers.

We have developed zinc-bismuth-phosphate glasses, which have deformation temperatures under 450°C and refractive indices higher than 1.7, in order to produce an antireflection structure on the surface by a glass-imprinting process. Two-dimensionally arrayed conical cavities of sub-wavelength size were fabricated on a SiC mold by electron lithography and dry etching techniques. The sub-wavelength periodic structure was transferred onto the glass surface by a glass-imprinting process using the mold. The sub-wavelength structure suppressed the reflectance by approximately 90%. A weak maximum was observed in the reflection spectra around 400–500 nm, which decreased in intensity and shifted toward shorter wavelengths with decreasing pitch.

Novel quaternary hydrides Mg 7− x A x TiH 16− x (A = Li, Na, K) have been synthesized by use of an ultrahigh-pressure (UHP) technique. The Rietveld refinements for synchrotron X-ray diffraction (XRD) patterns suggest that added LiH and NaH greatly enhanced the yield of the Mg 7 TiH 16 phase. The unit cell volumes of the Mg 7− x A x TiH 16− x phases were increased with increasing the amount and the ionic radii of the alkali metals. The reversibility of the hydrogen releasing and restoring reactions was much improved by the addition of alkali metal hydrides. The reversible hydrogen storage capacities were around 3–4 wt.% for the Mg 7− x A x TiH 16− x phases on the pressure–composition isotherm (PCI) measurements. Obtained enthalpy values tend to be reduced with reducing the Δ H of the alkali metals.

We have studied the temperature coefficient of the refractive index of synthetic silica glasses with various hydroxyl impurities. The refractive index was measured at 15 °C and 35 °C at 1.707–0.238 μm wavelengths. The temperature coefficient of a low-OH group (110 wt. ppm) containing glass increased from 8.0 ± 0.2 × 10−6/°C (at 1.707 μm) to 14.0 ± 0.2 × 10−6/°C (at 0.238 μm), although it increased respectively from 7.0 ± 0.2/°C to 12.0 ± 0.2 × 10−6/°C for a high-OH group (1300 wt. ppm) containing glass. The three-term Sellmeier equation, having two terms with resonance photon energies in the vacuum ultraviolet region and one term in the infrared region, was used to analyze the wavelength dispersion of the refractive index. Increasing temperatures shifted the resonance energy in the second term by −4.14 ± 0.4 × 10−4 eV/°C for low-OH (110 wt. ppm) glass and −2.64 ± 0.4 × 10−4 eV/°C for high-OH (1300 wt. ppm) glass. The fundamental absorption edge in the vacuum ultraviolet region shifted by −8.8 ± 0.7 × 10−4 eV/°C for the low-OH glass and −6.3 ± 0.7 × 10−4 eV/°C for the high-OH glass in a region of 25–100 °C. Both high-OH glass shift rates were lower than low-OH glass shift rates. The lower temperature coefficient for the Si–OH-related band probably explains the smaller temperature coefficient for high-OH glass: the absorption band of Si–O–H structure is located at lower energy side close to the fundamental absorption band associated with the Si–O–Si structure.

Optical properties were studied on ternary zinc bismuth phosphate glasses, which have two distinct glass-forming regions; low-P2O5 region and high-P2O5 region. Orthophosphate and isolated phosphate structures are dominant in the former region and metaphosphate and pyrophosphate structures are dominant in the latter region. Refractive index of the low-P2O5 glass (nd > 1.82) was relatively higher than that of the high-P2O5 glass (nd O bonding state between two glasses.

Magnesium-based hydrides with Zr or Hf have been synthesized by means of an ultra-high pressure technique. Powder mixtures of MgH2 and ZrH2 or HfH2 have been heated up to 873 K under 4–8 GPa in a multi-anvil cell. New ternary phases (Mg–Zr–H and Mg–Hf–H) with a face centered cubic (FCC) structure have been formed. In the Mg–Zr hydride, the FCC phase with disordered metal–atom occupancy was observed, while a Ca7Ge-type super-lattice structure was observed in the Mg–Hf hydride. By the temperature programmed desorption (TPD) measurements, these new hydrides exhibit the hydrogen-desorption at around 543–583 K, which were 130–70 K lower than that of MgH2 at a heating rate of 10 K/min under vacuum. Desorbed hydrogen contents were estimated to be 4.2 and 3.0 mass% for Mg–Zr and Mg–Hf hydrides, respectively.

It was found that the preparation ratio of the fcc Mg7TiH16 phase on the UHP synthesis was greatly enhanced by adding a small amount of LiAlH4. In addition, reversible hydrogen storage capacity of the sample was significantly increased. The Rietveld refinement results for synchrotron X-ray diffraction (XRD) data indicated that the Li ion would substitute the Mg site in the Mg7TiH16 phase. Differential scanning calorimeter measurements indicated that the LiAlH4 added Mg7TiH16 phase exhibited reversible hydrogen releasing and restoring behaviors under 0.1−0.5 MPa of hydrogen pressure. The reversible hydrogen storage capacities were in the range of 3.8−4 wt % on the pressure−composition isotherms.

Reduction in the temperature coefficient of the optical path length, d S /d T of Li 2 O–Al 2 O 3 –SiO 2 glass–ceramics with near-zero thermal expansion coefficient was attempted using control of the temperature coefficient of electronic polarizability, ϕ , and the thermal expansion coefficient, α . The d S /d T value of 2.6 mol% B 2 O 3 -doped glass–ceramic was 12.5 × 10 −6 /°C, which was 0.9 × 10 −6 /°C smaller than that of B 2 O 3 -free glass–ceramic. On the other hand, reduction in d S /d T through B 2 O 3 doping was not confirmed in precursor glasses. Results showed that reduction in d S /d T of the glass–ceramic through B 2 O 3 doping is caused by the reduction in ϕ . The reduction in ϕ from B 2 O 3 doping was probably attributable to numerical reduction in non-bridging oxide ions with larger ϕ value by the concentration of boron ions in the residual glass phase. In addition, application of hydrostatic pressure during crystallization was effective to inhibit precipitation of β -spodumene solid solution, which thereby decreases d S /d T . The d S /d T value of B 2 O 3 -doped glass–ceramic crystallized under 196 MPa was 11.7 × 10 −6 /°C. That value was slightly larger than that of silica glass. The α value of this glass–ceramic was smaller than that of silica glass.

住民が地域の課題解決に向けて討議し，何らかの意思決定を進めるプロセスを観察すると，討議の進め方，関係する技術・専門知識や地域に係る知識の扱い方において個人差が大きいことがわかる．これより討議のプロセスがどのように進むかが討議の内容に本質的な影響を与えることとなる．本研究では仮想的な住居地区における防災情報技術導入に関する討議の場を設け，参加者に整備費用の分担比率を求めるために実験的な討議を行ってもらい，そのやりとりを観察し，図式化する．この図式を用いた分析の結果から，一般的に住民討議を効率よく進行させるために考慮するべき事項を明らかにする．

Hydrogenation / dehydrogenation properties of a series of ternary face centered cubic (FCC) hydrides “Mg7MHx” (M = Sc, Ti, V, Zr, Nb, Hf and Ta), which were prepared by a high-pressure technique, were investigated. Differential scanning calorimeter (DSC) measurements under hydrogen atmosphere revealed that these hydrides exhibited reversible hydrogen releasing and re-storing properties at around 600 and 560 K, respectively. These releasing temperatures are lower by 100 ~ 120 K than that of MgH2. Furthermore, pressure-composition isotherm at 523 K shows that these FCC hydrides release 3.8 - 5 wt. % hydrogens.