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For the purpose of obtaining high critical current densities (J_c), well-oriented and connected Bi-2223 was prepared by improved processing techniques, i.e., (i) delamination by mild, wet grinding of a mixture of Bi-2212 and a supplemental phase containing Pb, Sr, Ca and Cu; (ii) preparation of green sheets by casting the slurry on a thin silver plate using an applicator bar; (iii) compression of the green sheet and calcination at 800°C in air; and (iv) firing at 827°C in 7% O₂-Ar gas flow. Holding samples under compression in each processing step after delamination promoted grain growth, degree of orientation, fraction of Bi-2223 and, accordingly, better connectivity of the grain colonies.

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Mechanically alloyed (MA) Al-Ti and Al-O-Ti complexes have been studied by X-ray absorption fine structure (XAFS) at the Ti K-edge. In the MA mixture of Al and Ti, the single pre-edge peak due to the electron transition 1s→3d disappears, and the intensity of the first nearest neighbor peak in the EXAFS structure function [mid]F(r)[mid] decreases. In the MA mixture of Al and TiO₂, hydrogel, the number of pre-edge peaks apparently decreases from three to one. At the same time, the intensity of the [mid]F(r)[mid] peak due to the first nearest neighbor increases, and its position approaches that of Al₂TiO₅. Similar phenomena are observed in the MA mixture of Al₂O₃ and TiO₂ hydrogels. These results suggest that mechanical stressing causes characteristic electronic interaction and the reconstruction of short-range order through intimate mixing at an atomic level. This accords with our previous NMR studies.

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Mechanically alloyed (MA) Al-Ti and Al-O-Ti complexes have been studied by X-ray absorption fine structure (XAFS) at the Ti K-edge. In the MA mixture of Al and Ti, the single pre-edge peak due to the electron transition 1s→3d disappears, and the intensity of the first nearest neighbor peak in the EXAFS structure function [mid]F(r)[mid] decreases. In the MA mixture of Al and TiO₂, hydrogel, the number of pre-edge peaks apparently decreases from three to one. At the same time, the intensity of the [mid]F(r)[mid] peak due to the first nearest neighbor increases, and its position approaches that of Al₂TiO₅. Similar phenomena are observed in the MA mixture of Al₂O₃ and TiO₂ hydrogels. These results suggest that mechanical stressing causes characteristic electronic interaction and the reconstruction of short-range order through intimate mixing at an atomic level. This accords with our previous NMR studies.

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Y₃Al ₅O₁₂:Ce³⁺ (YAG:Ce³⁺) nanophosphor powder was synthesized by glycothermal method, where a reaction between aluminum isopropoxide and acetates of yttrium and cerium(III) was induced in 1,4-butylene glycol in autoclave. According to X-ray diffraction profiles, YAG crystal structure was formed after glycothermal treatment at 300°C for more than 1h. The aggregation of the primary particles of ∼10nm diameter was confirmed by TEM observation and dynamic light scattering. The intensity of photoluminescence (PL) due to 5d→4f transition of Ce³⁺ increased with increasing the aging time at 300°C during glycothermal treatment. The inductively coupled plasma atomic emission spectroscopy revealed that the atomic ratio of Ce/(Y+Ce) remained unchanged irrespective of the aging time at 300°C. Therefore, this suggests that prolonged aging promotes the homogeneous incorporation of Ce³⁺ into the interior of particle. Based on the characterization by thermal analysis and infrared absorption spectroscopy, the coordination of 1,4-butylene glycol and acetate on the surface of YAG:Ce³⁺ nanophosphors possibly plays a significant role in the PL enhancement.

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Eu²⁺ doped CaS nanoparticles were prepared by two kinds of methods, alkoxide and co-precipitation. The as-prepared samples did not show any emission, while the heated samples showed the red emission corresponding to the 4f⁶5d¹→4f⁷ transition of Eu²⁺. No signal of Eu²⁺ was observed in the electron paramagnetic resonance spectra of the as-prepared samples, while the heated samples showed two sets of sextet hyperfine lines corresponding to two isotopes of Eu²⁺ with the mass numbers of 151 and 153. Accordingly, these results indicate that Eu²⁺ ions were incorporated into CaS during subsequent heating to show the red emission.

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A transparent colloidal solution of the ZnS:Mn²⁺ nanocrystal was prepared in hybrid reverse micelles comprising two kinds of surfactants: sodium bis(2-ethylhexyl)sulfosuccinate (AOT) and lauryl phosphate (HLP). Then, the powdered sample was obtained from the colloidal solution by coagulation of these micelles. Modification of HLP surfactant increases the photoluminescence (PL) intensity due to the d–d transition of Mn²⁺ ions for both of the colloidal solution and the powder. FT-IR spectra and energy dispersive X-ray analysis (EDX) data reveal that HLP modifies ZnS:Mn²⁺ nanocrystals more preferentially than AOT. The detailed investigation on chemical interaction between HLP molecules and ZnS nanocrystals with and without Mn²⁺ is performed by solid-state nuclear magnetic resonance (NMR) techniques of ³¹P inversion recovery and ¹H→³¹P cross-polarization (CP) in a magnetic field of 11.7T using magic angle spinning (MAS) at a high spinning rate of 19 and 28kHz, respectively. These NMR results suggest that most of HLP molecules strongly interact with nanocrystals through coordination bonds and/or hydrogen bonds.

▼ A batch method was used to investigate the uptake of heavy metal cations and anions by the compounds in the CaTiO₃-CaFeO_2.5 system, in which a series of oxygen vacancies was systematically introduced into a perovskite structure as the x-value of Ca(Fe_xTi_1-x)O_3-x/2 was increased. Samples of CaTiO₃, CaFe_0.1Ti_0.9O_2.95, CaFe_0.5Ti_0.5O_2.75, CaFe_0.67Ti_0.33O_2.67 and CaFeO_2.5 were prepared by solid mixing (SM), co-precipitation (CP) and gel evaporation (GE) methods. The resulting samples were calcined at temperatures between 400 and 1000^oC. The target crystalline phases differed according to the preparation method, but in most cases were formed at 700-800^oC. The Ni^2^+ sorption isotherms of all the samples were fitted better by the Langmuir model than by the Freundlich model, while in the case of H₂PO₄^- sorption isotherms, these were better fitted by the latter model. The uptake ability increased with increasing x value of the samples. The maximum values for the saturated sorption of Ni^2^+ (Q₀(Ni^2^+)=2.83mmol/g) and H₂PO₄^- (K_F(H₂PO₄^-)=2.95mmol/g) were achieved for x=1 (i.e. CaFeO_2.5) sample.

▼ Porous mullite ceramics with unidirectionally oriented pores were prepared by an extrusion method using rayon fibers as the pore formers and the characteristics of microbubbles generated by these porous ceramics were investigated. The 1200mm long ceramics were tubular and of thick or thin types of 20-30mm inner diameter and 30-50mm outer diameter, respectively. The thin and thick samples had porosities of 47 and 49% and average pore radii of 7.8μm. The gas permeabilities of the thick and thin samples were 4.1x10^-^1^4 and 5.4x10^-^1^4m^2, respectively. Microbubbles were generated by introducing N₂ gas through the ceramic tube by immersing it into water. The minimum pressure (bubble point pressure) for generation of microbubbles was 20kPa, much lower than for other bubble-forming methods. The average microbubble radii ranged from about 70 to 105μm at flow rates of 0.15-0.25L/min in the thin sample and 0.3-0.7L/min in the thick sample. These bubble sizes are much smaller than calculated for a Fritz-type bubble such as generally formed by bubbling from pores and/or orifices. However, the present bubble sizes agree well with the calculated value based on nanobubbles, indicating that bubble formation occurs by mixing the gas with water in small pores. Since microbubbles enhance the dissolution rate of a gas phase in water, they are potentially useful for improving water environments, especially oxygen-deficient water. The effectiveness of gas dissolution in water was confirmed by determining the dissolution behavior of CO₂ gas using these porous ceramics.

▼ The geopolymers were prepared from sodium silicate, metakaolinite, NaOH and H₂O at SiO₂:Al₂O₃:Na₂O:H₂O of 3.66:1:1:x, where x=8-17, and curing temperatures of 70-110^oC. Since the bending strength of the geopolymers was highest (36MPa) where H₂O/Al₂O₃=9 and the curing temperature=90^oC, these conditions were adopted. The porous geopolymers were prepared by kneading PLA fibers of 12, 20 and 29μm diameter into the geopolymer paste, at fiber volumes of 13-28vol%. The resulting paste was extruded using a domestic extruder, cured at 90^oC for 2 days then dried at the same temperature. The PLA fibers in the composites were removed by alkali treatment and/or heating. The highest capillary rise was achieved in the porous geopolymers containing 28vol% of 29μm fibers. The capillary rise of this sample, estimated by the equation of Fries and Dryer^1 was 1125mm.

▼  A 59-year-old woman was admitted to our hospital complaining of a productive cough, dyspnea on effort, and low-grade fever. Although chest X-rays showed no marked abnormalities, her level of serum KL-6 was extremely high. We therefore suspected the presence of interstitial pneumonia. High-resolution computed tomography (CT) scan revealed infiltrative shadows in S6 of the right lung, and her serum was positive for antihuman T-lymphotropic virus type 1 (HTLV-1) antibodies. From the clinical symptoms, radiographic findings, and histological findings, the diagnosis was probable lymphocytic interstitial pneumonia (LIP). After high-dose corticosteroid therapy, the level of serum KL-6 decreased rapidly. We conclude that KL-6 is a convenient and reliable marker for evaluating the activity of pulmonary manifestations in HTLV-1 carriers and that it is especially useful in monitoring the effectiveness of treatments.

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Summary

We describe a case of plasma cell leukemia associated with myelofibrosis. A 60-year-old woman was admitted due to lumbago and monoclonal hypergammaglobulinemia. Peripheral blood showed about 40% of plasma-cell-like cells. A bone marrow aspiration was dry tap. The patient was diagnosed as having plasma cell leukemia with myelofibrosis by bone marrow biopsy. Plasma cell leukemia as well as myelofibrosis improved with combination chemotherapy using vincristine, pirarubicin, and dexamethasone. However, when plasma cell leukemia became resistant to chemotherapies, myelofibrosis also reappeared. This case strongly suggests the pathogenetic relationship between plasma cell leukemia and myelofibrosis.

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We developed a prototype time projection chamber using gas electron multipliers (GEM–TPC) for high energy heavy ion collision experiments. To investigate its performance, we conducted a beam test with three kinds of gases (Ar(90%)–CH₄(10%), Ar(70%)–C₂H₆(30%) and CF₄). Detection efficiency of 99%, and spatial resolution of Formula Not Shown in the pad-row direction and Formula Not Shown in the drift direction were achieved. The test results show that the GEM–TPC meets the requirements for high energy heavy ion collision experiments. The configuration and performance of the GEM–TPC are described.

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A prototype Time Projection Chamber (TPC) using pure CF₄ gas was developed for possible use in heavy ion experiments. Basic characteristics such as gain, drift velocity, longitudinal diffusion and attenuation length of produced electrons were measured with the TPC. At an electric field of 900V/cm, the drift velocity and longitudinal diffusion for 1cm drift were obtained as Formula Not Shown and Formula Not Shown , respectively. The relatively large gain fluctuation is explained to be due to the electron attachment process in CF₄. These characteristics are encouraging for the measurement of the charged particle trajectories under high multiplicity conditions at RHIC.

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We have produced Gas Electron Multiplier (GEM) using the plasma etching method. The new GEM has holes with a cylindrical shape and can hold up to 520V in nitrogen. Amplification factor was measured as a function of the applied voltage. A gain of 10⁴ was obtained in argon-mixture gases. The gain characteristics are very similar to those of the GEMs made at CERN.

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When the screen-printed ZnS:Mn²⁺ nano-phosphor film is heated under ambient condition, the photoluminescence (PL) intensity due to the d–d transition of Mn²⁺ decreases with increasing temperatures. The coating of 3-mercaptopropyl trimethoxysilane (MPS) and SiO₂ around ZnS:Mn²⁺ nanoparticles is effective to suppress the decrease in the PL intensity by heating. This is explained by suppressing the oxidation of ZnS:Mn²⁺ nanoparticles and the carbonization of propyl chain in MPS by SiO₂ coating.

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Fine particles and thin films of NiO/SiO₂ mixed gels, prepared from a bidentate alkoxide, were irradiated by a XeCl excimer laser or by a corona discharge. A part of NiO was initially dissolved in SiO₂, and was segregated and crystallized on heating at 10 K min⁻¹ to 800°C in air. Subsequently, amorphous SiO₂ crystallized into cristobalite at 900°C. Based on the change in the interplanar spacing of cristobalite, ultraviolet irradiation or discharge promoted the segregation of NiO. Transmission electron micrographs of substrateless gel thin films revealed that corona discharge treatment brought about the formation of uniform NiO particles as small as 5 nm.

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The effects of vibration ball-milling of a mixture of two gels, prepared from mixing ZrO₂ and TiO₂ sols, on crystallization processes during heating are studied in order to determine enhanced mechanochemical reactions with the aid of hydroxyl groups. Data of differential thermal analysis (DTA) and X-ray diffractometry show that TiO₂ (anatase) and ZrO₂ (tetragonal) crystallized at 698 and 712 K, respectively, when a powdered gel mixture was heated to 1023 K at 10 K min⁻¹ in air. No reactions between the two phases were detected. After vibro-milling a powdered gel mixture at room temperature for 3 to 30 h, a new exothermic DTA peak appeared around 950 K and ZrTiO₄ (orthorhombic) was detected on heating to 1023 K. After vibro-milling, the compositional micro-homogeneity of non-heated gels was estimated from the fluctuations of elemental compositions in local areas using energy dispersive spectrometer with a 25 nm electron beam. The fraction of ZrTiO₄ crystallized on heating the gels to 1023 K, determined by Raman spectroscopy, increased linearly with increasing the micro-homogeneity for non-heated gels. It is suggested that atomic movement and short-range ordering of ZrTiO₄ rather than crystallization of individual oxides occur when applying mechanical stress to a powdered mixture of ZrO₂ and TiO₂ gels.

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Fused silica plates were implanted with i⁵⁸Ni⁺ temperature to a dose of 6 × 10¹⁶ ions cm⁻² under the condition of 160 keV and 3 μA cm⁻². The changes in the optical and magnetic properties of Ni⁺ -implanted silica by annealing at 800°C for 4 h in air, N₂ and Ar with 4% H₂ were measured to determine the chemical state of implanted nickel species. The absence of change in the depth distribution of Ni after annealing under these conditions indicates that nickel species did not dissolve in silica. The absorption band due to the surface plasmon resonance of Ni particles at ∼ 3.6 eV decreased and increased on annealing in air and Ar with 4% H₂, respectively. The intensity of the ferromagnetic resonance signal measured at −196°C was larger than that at room temperature, both increasing with heat treatment. The resonance field depended on the angle between the implanted surface and the applied magnetic field. It is concluded that Ni particles embedded in silica by ion-implantation were magnetized in the plane normal to the ion beam and that super-paramagnetic Ni changed to ferromagnetic Ni during the thermal treatment.

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The effects of ball-milling a sol, prepared from Ni-Si bidentate alkoxides, on the segregation of NiO from SiO₂ during subsequent heating are studied for the purpose of fabricating composites in which the nanosized microstructure is controlled. After dissolving a nylon substrate on which gel films were deposited, the films were heated to 500°C in air. Transmission electron micrographs of substrateless gel films showed that the agglomeration of NiO particles, formed in the films, decreased by ball-milling a sol. A similar phenomenon was also observed on ball-milling gel powders. The infrared absorption bands due to Si-O asymmetric stretching vibration became broader by ball-milling. This broadening also occurred when NiO segregated from SiO₂ by heating a non-milled gel powder above 700°C. It is suggested that ball-milling produced a more homogeneously distributed nucleation of NiO particles through the breakage of bends between O²⁻ and Ni²⁺ incorporated into SiO₂ networks.

▼ An approach to control the diameter of high-aspect-ratio pores formed into a silicon wafer by an electrochemical etching process is reported. Hole (h^+) was involved in the etching reaction and the collection of the h^+ was the key factor. Artificial micro-cavities were fabricated on the silicon surface prior to the etching. The depth of the space charge region (SCR), Schottky barrier on the silicon-electrolyte interface, was adjusted regarding the depth of the micro-cavities by applied overpotential and specific resistance of the silicon wafer. The collection of h^+ at the tip of the cavity site was widely controlled by the adjusted SCR. Consequently the electrochemically etched domain at the cavity site was actively tuned, and then high-aspect-ratio pore with the controlled diameter was formed. The diameter was tuned by the SCR depth which was controlled by the overpotential and the specific resistance. The diameter tuning mechanism worked under the mask-free condition.

▼ The stability of indomethacin (IM) compounded with SiO₂ either by co-grinding or by melt-quenching was examined by recrystallization kinetics under the conditions 30^oC and 11% relative humidity. A decrease of the recrystallization rate with and without an appreciable induction period was observed in both compounds. Higher stability of amorphous IM compounded with SiO₂ was attained by prolonged co-grinding than by melt-quenching. This was explained by the stronger chemical interaction at the interface between IM and SiO₂ by co-grinding, as revealed by ^2^9Si and ^1^3C solid state NMR. Incomplete co-grinding with the rest of the crystalline state, however, made the amorphous state appreciably unstable, since the remaining crystallites serve as seeds for recrystallization.

▼ Mg-Al-ascorbic acid (ASA)-layered double hydroxides (ASA-LDHs) with Mg/Al=3 were synthesized by ion-exchange, coprecipitation and reconstruction methods. Composites with sodium oleate (SOA)/ASA-LDH were prepared by an ion-exchange method using various concentrations of SOA solutions. The (003) basal spacing of the ASA-LDHs changed from 0.76nm in the CO₃-LDH to 0.78 and 0.86nm after intercalation of the ASA ions and these basal spacings are in good agreement with models based on the assumption as mono layers and double layers of ASA ions in the LDH interlayers, respectively. The amounts of ASA in the LDHs prepared by the reconstruction method were higher than those by the ion-exchange and coprecipitation methods. In the preparation of composites of SOA/ASA-LDH, an ion-exchange method was more suitable than a reconstruction method to cause surface sorption of the SOA molecules with maintaining intercalated ASA ions in the LDH interlayers. The acid-resistant properties of the composites of SOA/ASA-LDH were found to be much higher than for the pure ASA-LDH and mixture of CO₃-LDH and ASA. The surfaces of the LDH particles in the composites are, thus, mostly covered with sorbed SOA molecules and they are good candidates as drug delivery materials for intestines through the stomach.

▼ Porous Al₂O₃ ceramics were prepared using a two-step sintering method. Green bodies were prepared using the slip cast method. The average pore size and porosity of the obtained samples were, respectively, 73nm and 42%. The porosities and the average pore size of the samples prepared using a one-step sintering method decreased concomitantly with increasing sintering temperature. The porosity was mostly constant at temperatures higher than 1300^oC. The T₁ and T₂ temperatures were set, respectively as 1150^oC and 1000^oC for two-step sintering tests. Under these conditions, the pore size was controllable by sintering time without porosity change. The average pore size of the obtained samples was 61-76nm without porosity change.

▼ Diacylglycerol kinase (DGK) is involved in the regulation of lipid-mediated signal transduction through the metabolism of a second messenger diacylglycerol. Of the DGK family, DGKζ, which contains a nuclear localization signal, localizes mainly to the nucleus but translocates to the cytoplasm under pathological conditions. However, the detailed mechanism of translocation and its functional significance remain unclear. To elucidate these issues, we used a proteomic approach to search for protein targets that interact with DGKζ. Results show that nucleosome assembly protein (NAP) 1-like 1 (NAP1L1) and NAP1-like 4 (NAP1L4) are identified as novel DGKζ binding partners. NAP1Ls constitutively shuttle between the nucleus and the cytoplasm in transfected HEK293 cells. The molecular interaction of DGKζ and NAP1Ls prohibits nuclear import of DGKζ because binding of NAP1Ls to DGKζ blocks import carrier proteins, Qip1 and NPI1, to interact with DGKζ, leading to cytoplasmic tethering of DGKζ. In addition, overexpression of NAP1Ls exerts a protective effect against doxorubicin-induced cytotoxicity. These findings suggest that NAP1Ls are involved in a novel molecular basis for the regulation of nucleocytoplasmic shuttling of DGKζ and provide a clue to examine functional significance of its translocation under pathological conditions.

▼ Mechanisms for decomposition of 10mol% Sc₂O₃ and 1mol% CeO₂ co-doped ZrO₂ (10Sc1CeSZ) electrolytes of a cathode-supported tubular-type SOFC during the long term operation for >=100h have been investigated by analyzing SEM, Raman spectroscopy and XPS of decomposed samples and also by additional examination for the effects of impurities (MnO₂, Al₂O₃ and Si) on the decomposition of electrolyte. The valence of manganese at the decomposed parts in the fuel side was found to become higher after the long term operation. This leads to the driving force for the decomposition of 10Sc1CeSZ into two phases by the large oxygen potential gradient developed on the surface in the fuel side. The kinetic factors for formation of new phases are considered to be as follows; the Si component in the fuel can be a trigger to form MnSiO₃ which worked at the nucleation points, and the valence changes of manganese in the electrolyte proceed the decomposition cycles consisting of two phase separation in the zirconia, pulverization of manganese-rich phase and detachment of zirconia-based oxides.

▼ Transglutaminases (TGases) are enzymes which catalyze cross-link formation between glutamine residues and lysine residues in substrate proteins. We have previously reported that one of the TGases, blood coagulation factor XIIIa (FXIIIa), is capable of mediating adhesion of various cells. In this paper, we report for the first time that tissue-type transglutaminase (TGc) also has cell adhesion activity. TGc-coated plastic surface promoted adhesion and spreading of cells in a TGc concentration-dependent manner. However, there are some obvious differences between cell adhesion mediated by TGc and FXIIIa. As was reported previously, the adhesion to FXIIIa is dependent on its TGase activity. In contrast, the TGc-mediated cell adhesion is independent of its TGase activity: 1) The modification of the active center cysteine with iodoacetamide blocked the enzyme activity without any effect on cell adhesion; 2) the addition of Mg^2^+ did not induce the enzyme activity, but it was as effective as Ca^2^+ for cell adhesion; 3) the addition of NH₄^+ inhibited the enzyme activity but did not affect the cell adhesion significantly. The integrins involved in these cell adhesions are quite different. In the case of FXIIIa, αvβ3 and αSβ1 integrins are involved and consequently the RGD peptide substantially inhibited the adhesion. On the other hand, the cell adhesion to TGc is mediated by α4β1 integrin but not αSβ1; a CS-1 peptide, which represents the binding site of fibronectin to α4β1 integrin, completely inhibited the cell adhesion to TGc. It is possible that TGc and FXIIIa may mediate cell adhesion under different physiological and pathological situations.

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Eight patients to received Boron Neuron Capture Therapy (BNCT) were selected from 33 newly diagnosed glioblastoma patients (NCT(+) group). Serial 42 glioblastoma patients (NCT(−) group) were treated without BNCT. The median OS of the NCT(+) group and NCT (−) group were 24.4 months and 14.9 months. In the high risk patients (RPA class V), the median OS of the NCT(+) group tended to be better than that of NCT(−) group. 50% of BNCT patients were RPA class V.