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The BaSO4 scales obtained from piping decontamination from oil and gas industries are most often classified as low level radioactive waste. These wastes could be immobilised by stable cement matrix to provide higher safety of handling, transportation, storage and disposal. However, the information available for the effects of the basic formulation such as waste loading on the fundamental properties is still limited. The present study investigated the effect of BaSO4 loading and water content on the properties of OPC–BaSO4 systems containing fine BaSO4 powder and coarse granules. The BaSO4 with different particle size had a marked effect on the compressive strength due to their different effects on hydration products formed. Introduction of fine BaSO4 powder resulted in an increased formation of CaCO3 in the system, which significantly contributed to the compressive strength of the products. Amount of water was important to control the CaCO3 formation, and water to cement ratio of 0.53 was found to be a good level to maintain a low porosity of the products both for fine BaSO4 powder and coarse BaSO4 granule. BaSO4 loading of up to 60 wt% has been achieved satisfying the minimum compressive strength of 5 MPa required for the radioactive wasteforms.

Tunneling measurements of the electron spectrum in the superconducting state have been carried out in Y 2 C 3 samples with the bulk (resistive and diamagnetic) critical temperature T c = 15–16 K. A break-junction technique was crucial to find the intrinsic gap features. The representative gap structure at 4 K reveals distinct BCS-like peaks with the gap value of 2 Δ (4 K) = 3–4 meV. Assuming local T c values of 10–13 K, the characteristic gap to T c ratio 2 Δ / k B T c ( k B is the Boltzmann constant) was found to possess the BCS weak-coupling value 3.5 ± 0.2, appropriate to isotropic s -wave superconductors.

The problem of skill-level-dependent modulation in the joint dynamics of multi-joint arm movements is addressed in this study using piano keystroke performed by expert and novice piano players. Using the measured kinematic and key-force data, the time varying net, gravitational, motion-dependent interaction (INT), key-reaction (REA), and muscular (MUS) torques at the shoulder, elbow, wrist, and metacarpophalangeal (MP) joints were computed using inverse dynamics techniques. INTs generated at the elbow and wrist joints, but not those at the MP joint, were greater for the experts as compared with the novices. REA at the MP joint, but not at the other joints, was less for the experts as compared with the novices. The MUSs at the MP, wrist, and elbow joints were smaller, and that at the shoulder joint was larger for the experts as compared with the novices. The experts also had a lesser inter-strike variability of key striking force and key descending velocity as compared with the novices. These findings indicated that the relationship among the INT, REA, and MUS occurring at the joints of the upper-extremity differed between the expert and novice piano players, suggesting that the organization of multi-joint arm movement is modulated by long-term motor training toward facilitating both physiological efficiency and movement accuracy.

We have succeeded in synthesizing a new member of ternary silicide NaAlSi with a superconducting transition temperature T c−onset = 7 K by high pressure technique. The crystal structure of NaAlSi is the layered diamond-like structure with a space group of P 4/ nmm (no. 129, Z = 3) and without inversion symmetry. The superconducting properties in NaAlSi have been investigated by means of DC and AC magnetic susceptibility measurements. These magnetic responses indicate that NaAlSi belongs to a conventional type-II superconductor with a Ginzbrug–Landau parameter κ = 13.8. From the band structure calculations, we found that the hole band of Si p- and electron Al s-orbitals play an important role for the superconductivity in this system.

The matrix and heat affected zone (HAZ) of welded SUS304 steel has been irradiated in an 1250 kV high voltage electron microscope at 673 K to 5.4 dpa (displacements per atom) to study the effect of electron irradiation on microstructure. In situ observation shows the voids formed by electron-beam irradiation coalescence which grew to larger sizes with irradiation dose. Values of void size, void number density and void swelling in HAZ were larger than those of the matrix, and these increased and saturated gradually with irradiation dose. Non-equilibrium segregation phenomenon involving Cr depletion and Ni enrichment at grain boundaries were also observed in both the HAZ and matrix of welded SUS304 steel.

The water cooled shield blanket made of Type 316L SS for the international thermonuclear experimental reactor (ITER) has potential issues related to stress corrosion cracking (SCC). Shroud mock-ups and boat samples taken from the core shroud of the boiling water reactor (BWR) with SCC were investigated from the viewpoint of microstructures and nano-hardness. Fine grains and deformation bands were observed in the hardened surface thin layers of the shroud mock-up, where hardness profiles in the ground portion was different from those in the milled portion. In the fine grain region, crevices were found only in the ground surface. In the core shroud, hardened surface regions were also found. Results showed that the crevices found on the ground surface could be one possible factor for SCC initiation.

This report describes a 37-year-old man with 3 erupted supernumerary teeth in the maxilla and 6 impacted supernumerary teeth in the mandible, 2 of which were fused (a double tooth and a triple tooth).

We perform numerical simulations to investigate the apsidal motion in the planetary systems, v Andromedae, HD 12661 and 55 Cancri. The first two systems are in symmetric apsidal librations about 0° and 180° respectively, and the last appears to be in an asymmetric Δω-libration. We underline that the apsidal librations do play a significant role in maintaining the stability of the planetary systems.

The Japan Marine Science and Technology Center (JAMSTEC), the Ocean Research Institute, University of Tokyo and the Laboratoire de Geologie, Ecole Normale Superieure at Paris carried out in collaboration a 120-channel reflection seismic survey using an airgun array with total 4200 cubic inch capacity around the eastern Nankai trough in 1996. Data obtained by R/V Hakuho, University of Tokyo were primarily processed by JAMSTEC and were shared by the above three main bodies of this program to complete geoscientific interpretation. The fault configuration around the eastern Nankai trough is very complicated due to the collision of the Izu Peninsula against central Japan. The major remarkable faults around the eastern Nankai area are the Zenisu, the Kodaiba and the Tokai thrusts. The main objective of this paper is to clarify these fault configurations. The Zenisu thrust dips gently northward from the southern slope of the Zenisu ridge, and reaches the oceanic Moho. The location of the Tokai thrust may jump at the Tenryu canyon, and appears to reach the top of the subducting oceanic plate. The Kodaiba fault penetrates a 5.5–5.6-km/s layer, which is the crust of the central Japan forearc. A large fault in the trough axis cuts the entire oceanic crust and has a flower structure, which indicates that it has strike-slip component. Its strike is NW–SE, parallel to the plate motion and perpendicular to the strike of the Zenisu ridge. The top of the subducting oceanic crust of the Philippine Sea plate was defined beneath the continental slope of the central Japan forearc. The angle of subduction becomes abruptly steeper 50 km north of the deformation front. We also observed at the southern roof of the Zenis thrust a drape fold structure which is proof of subduction. We suggest a subduction on the southern side of the Zenisu ridge, strongly deformed oceanic crust at the trough axis and some major faults in the forearc region reaching subducting oceanic crust.

A general control system of the Material and Life Science Experimental Facility (MLF-GCS) of Japan Proton Accelerator Research Complex (J-PARC) is required to control all the subsystems of the MLF including the muon and neutron target, moderator, target station, experimental hall, and so on. It is an independent system, but it has to work closely with the control systems of accelerator and other facilities in J-PARC. A conceptual design of MLF-GCS has already been conducted and detailed designs are now in progress. This paper gives an overview of the MLF-GCS and reports on its development status.

To develop multilayer mirrors for use at wavelengths shorter than 12.4 nm in soft X-ray projection lithography, Ni/C multilayers were fabricated using r.f. sputtering. Evaluation of their layered structure and reflectivity showed that multilayer deposited at about 80 °C had substantial interface roughness, while those deposited at about −20 °C had well-formed layers with a periodic length of about 5.5 nm and an interface roughness of 0.25 nm. A fabricated Ni/C multilayer with 35 pairs of 2.3 nm Ni and 3.2 nm C layers showed a high measured reflectivity of 18% at a wavelength of about 7 nm.

Electrochemical oxidation of dihydronicotinamide adenine dinucleotide (NADH) occurred at less-positive potentials at a plastic formed carbon electrode (PFC) compared with ordinary electrodes such as a glassy carbon electrode. The PFC electrode produced reproducible voltammograms for the oxidation of NADH in repeated use without any treatment, and when the PFC electrode was covered with a dialysis membrane, the electrode produced steady-state currents linearly proportional to the concentration of NADH. The dialysis membrane-covered electrode could be used for the measurements of the activity of NAD-dependent enzymes by monitoring the time-dependent decrease in the current and thus for the assay of the enzymes in clinical analysis. The PFC electrode also produced quasi-reversible waves for the redox reactions of the molecules of biological importance such as quinones and flavins.

We have studied the low-frequency voltage noise in micron-scale magnetic tunnel junctions. Random telegraph noise (RTN) dominates over 1/ f noise in the switching region of magnetic hysteresis loops, suggesting that RTN comes mostly from local magnetization fluctuations. The temperature dependence of the 1/ f noise and the size of the magnetic fluctuators responsible for the RTN are discussed.

A series of 2,4-dioxo-thieno[2,3- d ], [3,2- d ] and [3,4- d ]pyrimidin-1-acetic acids ( 2 ) with a benzyl moiety at the N-3 position were prepared and tested in vitro for aldose reductase inhibitory activity against partially purified enzyme from rat lens. Some of these compounds were also evaluated for inhibition of sorbitol accumulation in the sciatic nerve or lens of streptozotocin-induced diabetic rats in vivo . Among the synthesized compounds, several showed potent aldose reductase inhibitory activity with IC 50 s in the 10 −8 M range. Particularly, the potencies of non-substituted thieno- ( 2a and 2aa ), 5-methylthieno- ( 2c ), 5,6-dimethylthieno-( 2g ), 6-isopropylthieno- ( 2j and 2k ), 6-chlorothienopyrimidine ( 2q ) and benzothienopyrimidine ( 2ac ) analogs were approximately equipotent to FK-366 ( 1A ) and Ponalrestat ( 1B ) as references. Although most compounds were inactive in vivo , 2 compounds, 2k and 2q , possessed moderate in vivo activity.

Double beta (ββ) decays of 100Mo and charge nonconserving (CNC) X-ray and γ-ray transitions in 127I were studied by means of ELEGANTS V. Afinite half-life of T 1 2 2ν = 1.15 −0.20 +0.30 × 10 19 yr(68%CL) for the two neutrino ββ decay and the lower limit of T 1 2 0ν > 7 × 10 21 yr(68%CL) for the neutrino-less ββ decay were obtained. This corresponds to the mass limit of mν 127 I + e K → 127 I ∗ + ν and 127 I + e K → 127 I + ν were obtained as τ > 5.8 × 1022yr and τ > 1.2 · 1023yr, respectively. Upper limits on the ratios of the CNC strengths to the charge conserving ones for the weak and electromagnetic processes were obtained as ϵW2

Exotic K X-ray emission from neutral iodine atoms was searched for by using a large volume NaI detector. The most stringent upper limit on the K X-ray emission rate was obtained as 8.3 × 10 −24 yr −1 . It leads to the most stringent upper limits ϵ W 2 −30 , ϵ γ 2 −45 and δ NP 2 −46 for the relative strengths of the charge non-conserving (CNC) weak process, the CNC electromagnetic process, and of the non-paulian K X-ray emission, respectively.

Double beta (ββ) decays of 100Mo were studied by means of ELEGANTS V. A finite half-life of T 2v 1 2 =(1.15 +0.30 −0.20 )×10 19 yr (68% CL ) for 2νββ decay and the most stringent lower limit of T 0v 1 2 > 4.7 × 10 21 yr (68% CL ) on the half-life for the 0vββ decay were obtained. The observed T 2ν 1 2 indicates very severe cancellation of the components of the relevant nuclear matrix element.

Previous evidence has shown clearly that sugar cataract formation results from unusually high intracellular levels of polyol. Documentation of polyol-related histological changes in the cortical fiber cells of the equatorial zone has been extensive. However, little attention has been given to the early changes in the lens epithelial cells, in spite of the fact that the highest level of aldose reductase is found in this layer of the lens. Also, cultured lens epithelial cells exposed to high sugar levels exhibit rapid accumulation of polyol and show ultrastructural alterations. Therefore, a study was designed to evaluate the role of the lens epithelium in sugar cataract formation. Specifically, an attempt was made to localize the earliest fine structural lesions in intact lenses of galactose-fed rats and to test their relation to aldose reductase. Rats were fed either a normal diet or a 50% galactose diet with or without sorbinil, an aldose reductase inhibitor. Rats were killed at varying periods of time ranging from 6 to 96 hr, and the eyes were processed for light and electron microscopy. The first detectable abnormalities occurred after 36 hr of galactose feeding, and were limited to the central lens epithelium. Cell edema, apparent dilution of cytoplasm, rounding of nuclei, aberrant intracellular vacuoles, and loss of normal tortuosity of cell boundaries were the salient lesions. No changes were detectable in the equatorial zone until 48 hr, and no deviation from the control structure was found in any of the rats treated with an aldose reductase inhibitor.(ABSTRACT TRUNCATED AT 250 WORDS)

Recent evidence obtained from both galactosemic dogs and rats indicated that aldose reductase inhibitors could prevent several capillary lesions which were similar to those typical of diabetic retinopathy in humans. The present study demonstrates that diabetes-like histopathological changes in the intact retina, which were not visible in the vessel whole mounts used previously, can also be prevented. Sprague-Dawley rats were fed diets containing 50% galactose with or without an aldose reductase inhibitor (tolrestat). After 28 months of galactose feeding, the findings from retinal transections examined by light and electron microscopy were consistent with reports on vessel whole mounts, but showed several additional changes. There was a marked increase in the thickness of the retinal inner limiting membrane, as well as in the capillary basement membranes. There was extensive gliosis and disruption of retinal layers as well as pericyte degeneration, endothelial cell proliferation, accellularity, capillary dilation, and microaneurysm formation. The contents of pericyte compartments in the capillary wall were often replaced with non-pericyte cytoplasm, which appeared glial cell-like. Many of the lumens of acellular capillaries were occluded with debris from degenerating endothelial cells or with cytoplasm possibly originating from glial cell processes. Structures suggestive of degenerated microaneurysms were present mainly in the inner nuclear and outer plexiform layers. The microaneurysms and other major changes were limited to the central and paracentral retina. All these retinal lesions were prevented with orally administered tolrestat. Thus, long-term galactosemia in rats induced histopathologically visible angiopathies, simulating those occurring in background diabetic retinopathy in humans, and these were prevented by treatment with an aldose reductase inhibitor.

The in vitro effects of phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine, sphingomyelin, lysophosphatidyl choline, lysophosphatidyl ethanolamine, lysophosphatidyl serine, glycerophosphoryl choline, and phosphatidic acid on rubidium uptake and amino acid transport of rat lens are presented. None of these lipids affected the rubidium uptake mechanism; however, a large increase in the apparent leak-out of rubidium was observed with lysophosphatidyl choline. Lysophosphatidyl choline also inhibited all of the amino acid transport systems (A, ASC, L, Gly, Ly and β) as well as the uptake of inositol.

Changes in crystallin synthesis and crystallin mRNA content were followed in the epithelial and fiber cells of rat lenses during the development and reversal of galactose cataracts. Crystallin synthesis was not lowered in the lens epithelial cells throughout the 18 days of galactose feeding. By contrast, crystallin synthesis appeared partially reduced in the fiber cells of cultured lenses after the rats had been on a diet of 50% galactose for 6 days, and was essentially arrested in the lens fiber cells after the rats were fed galactose chow for 12 or 18 days. In vitro translation tests in a rabbit reticulocyte lysate demonstrated that control lenses contained α-, β- and γ-crystallin mRNAs in the cortical and nuclear fiber cells. The lens fiber cells of the 6-day galactosemic rats still possessed a full complement of crystallin mRNAs but those of the 15-day galactosemic rats had no detectable crystallin mRNAs. After 12 days the galactosemic lenses had lost approximately half of the crystallin mRNAs from the cortical fiber cells and all of the mRNAs from the nuclear fiber cells. Both crystallin synthesis and crystallin mRNA content recovered in the cortical fiber cells, but not in the nuclear fiber cells, during reversal of the galactose cataract. These results indicate that the reduction in crystallin synthesis is confined to the fiber cells and occurs initially by a decreased efficiency of utilization of crystallin mRNAs and subsequently by the degradation of the mRNAs. Previous experiments provide evidence that the impaired utilization of the crystallin mRNAs is due to the alterations in electrolytes in the cataractous lenses.

The proteins of the Rhesus monkey (Macaca mulatta) lens were studied and characterized. In general, there is a similarity of the monkey lens to the human lens particularly in the alpha- and beta-crystallins and the membrane proteins, although the amount of beta 1-crystallin may be greater in the monkey. There is immunological cross-reactivity in the crystallins between monkey and human lenses including the monkey low molecular weight proteins and the human low molecular weight proteins. The monkey lens low molecular weight material showed three differently sized proteins by gel exclusion chromatography. In this respect, the monkey lens proteins are similar to the human. However, the monkey lens low molecular weight proteins differ from the human low molecular weight proteins in charge as well as molecular weight determined by SDS-PAGE. One of the monkey low molecular weight proteins is more prevalent in the nucleus than in the cortex suggesting that this protein may be more important to the embryonic lens that to the adult lens.