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Although radiofrequency ablation for lung cancer is generally safe (with a mortality rate

Aims/Introduction To realize the effectiveness of a novel system for measuring glucose area under the curve (AUC) using minimally invasive interstitial fluid extraction technology (MIET), outpatients undergoing oral glucose tolerance tests (OGTT) were investigated for the efficacy of screening for glucose intolerance using this system. Materials and Methods Fifty outpatients scheduled to undergo a 75-g OGTT for medical reasons were recruited to the study. An area of skin on the forearm was pretreated with microneedle arrays before the application of hydrogels for interstitial fluid extraction. Plasma glucose (PG) levels were measured every 30 min for 2 h to calculate reference (actual) AUC. The AUC was predicted by MIET on the basis of glucose extracted by the hydrogel using sodium ion levels as the internal standard. Results Good correlation between MIET-predicted and reference AUCs obtained using PG levels was confirmed for a wide AUC range. By introducing a threshold level for AUC to separate glucose intolerance with peak glucose ≥180 mg/dL from normal glucose tolerance, the system was demonstrated to provide better screening accuracy compared with conventional methods that use HbA1c and fasting PG levels. The results of a questionnaire-based survey administered to the subjects suggested that this system was readily accepted by the majority as a painless monitoring method. Conclusions The findings suggest that our glucose AUC measurement system using MIET would be useful for screening of glucose intolerance. In the future, this system may prove to be a useful aid as a screen for glucose intolerance before performing an OGTT for diagnosis.

OBJECTIVE The aim of this study was to evaluate radiofrequency ablation (RFA) of lung tumors with dual-energy computed tomography while focusing on tumor composition and lung perfusion. METHODS The 36 tumors in 25 patients were included. Dual-energy computed tomography was performed before RFA and at 2 days and 1, 3, and 6 months thereafter. The effective atomic number (Zeff) of the tumors before RFA was compared with the Zeff at each follow-up using the paired t test. Lung perfusion was evaluated by iodine map images. When decreased perfusion was suspected after RFA, lung perfusion scintigraphy was performed. RESULTS The mean Zeff of the tumors significantly (P < 0.001) decreased at each follow-up, compared with that before RFA. Lung perfusion in the parenchyma peripheral to the tumors appeared to decrease at 2 days in 9 tumors, which was confirmed by scintigraphy in 7 tumors. CONCLUSIONS Dual-energy computed tomography was useful by providing additional information on tumor composition and lung perfusion.

Objective The goal of this study was to retrospectively evaluate the outcome, including feasibility, safety, diagnostic yield, and factors affecting the success of computed tomography fluoroscopy-guided biopsy when performed during the same procedure than radiofrequency ablation (RFA) in renal tumors strongly suspected of being T1a renal cell carcinoma (RCC). Materials and methods Nineteen patients (13 men, 6 women; mean age, 66.7 years) with a total of 19 suspected renal tumors (mean diameter, 1.8 cm) underwent computed tomography fluoroscopy-guided biopsy during ( n = 6) or immediately after ( n = 13) RFA. All patients were strongly suspected of having RCC on the basis of patient's medical histories and/or the results of imaging investigations. All procedures were divided into diagnostic and non-diagnostic biopsies. Various variables were compared between the 2 groups using univariate analysis. Results In all tumors, biopsy procedures were technically feasible. No major complications were observed, except for 8 minor post-procedural bleedings. All but one tumor was completely ablated. Local recurrence in the ablation zone as well as tumor seeding in retroperitoneal fat occurred in 1 patient 8.5 months after the procedure and were successfully treated with further percutaneous cryoablation. Thirteen tumors were diagnosed as RCC, whereas 6 were ultimately found to contain normal renal tissue ( n = 5) or connective tissue ( n = 1). Univariate analysis revealed that none of the variables were significantly different between the diagnostic and non-diagnostic biopsies. Conclusion The performance of renal tumor biopsy and RFA in the same session is feasible and safe. Although pre-treatment pathological diagnosis would be generally desirable, simultaneous biopsy with RFA can be an option for the patients who are not amenable to pre-treatment biopsy.

The concept, as well as the methodology of using a mineral-inspired approach in combination with solution parallel synthesis (SPS) for exploration of new phosphors among Na/Sr(Ba)/Al-silicate and Zr(Ti)-silicate minerals, is reported. By employing the proposed approach, we have discovered new phosphors of NaAlSiO4:Eu2+ and BaZrSi3O9:Eu2+, that emit green-yellow (553 nm) and blue-green (480 nm) light, respectively, when excited by radiation of 290 to 420 nm.

The cyanobacterium Microcystis produces volatile organic compounds such as β-cyclocitral and 3-methyl-1-butanol. The lysis of cyanobacteria involving the blue color formation has been occasionally observed in a natural environment. In this study, we focused on the oxidation behavior of β-cyclocitral that contributed to the blue color formation in a natural environment and compared β-cyclocitral with a structurally related compound concerning its oxidation, acidification, and lytic behavior. The oxidation products of β-cyclocitral were identified by the addition of β-cyclocitral in water, in which 2,2,6-trimethylcyclohex-1-ene-1-yl formate and 2,2,6-trimethylcyclohexanone were structurally characterized. That is, β-cyclocitral was easily oxidized to produce the corresponding carboxylic acid and the enol ester in water without an oxidizing reagent, suggesting that this oxidation proceeded according to the Baeyer-Villiger oxidation. The oxidation behavior of β-cyclocitral in a laboratory was different from that in the natural environment, in which 2,2,6- trimethylcyclohexanone was detected at the highest amount in the natural environment, whereas the highest amount in the laboratory was β-cyclocitric acid. A comparison of β-cyclocitral with structurally similar aldehydes concerning the lytic behavior of a Microcystis strain and the acidification process indicated that only β-cyclocitral was easily oxidized. Furthermore, it was found that a blue color formation occurred between pH 5.5 and 6.5, suggesting that chlorophyll a and β-carotene are unstable and decomposed, whereas phycocyanin was stable to some extent in this range. The obtained results of the characteristic oxidation behavior of β-cyclocitral would contribute to a better understanding of the cyanobacterial life cycle.

A facile approach, based on the polyelectrolyte-mediated electrostatic adsorption of a water-soluble titanium complex on colloid templates and hydrothermal treatment, is presented for the formation of hollow TiO2 spheres of the desired polymorphs. The core–shell particles were formed by the alternate deposition of titanium–glycolate complex 1 and positively charged polyelectrolyte, poly(allylamine hydrochloride) (PAH) on spherical polystyrene (PS) templates by utilizing electrostatic interactions for shell formation. Hollow spheres formed with the polyionic complex of 1 and PAH were obtained by removal of the PS templates. Formation of the polyionic complex affected the crystallization of TiO2 from 1 by hydrothermal treatment. Hollow spheres of brookite and anatase were obtained by hydrothermal treatment at pH 4 and 10, respectively. The approach presented here can be exploited for the fabrication of novel advanced titania-based materials with desired structures and polymorphs.

This article reports the luminescence properties of amphipathic YVO4:Er3+/Yb3+ nanoparticles (average grain size ca. 20 nm) obtained by an oleate-aided hydrothermal process. Depending on the upconversion (UPC) and downconversion (DWC) processes, they show luminescence in the visible and near-infrared (NIR) regions, respectively, by 980-nm excitation. The sample doped with Er3+:2.5 mol% and Yb3+:10 mol% showed the highest luminescence intensity in both the visible and NIR regions as a result of efficient energy transfer from Yb3+ to Er3+ ions. The hydrothermal treatment greatly enhanced both the DWC and UPC luminescence efficiencies. This is due to the reduction in the concentration of surface defects and ligands, accompanied by grain growth. NIR Fluorescence microscopy revealed for the first time that DWC luminescence is sufficiently intense for application of these nanocrystals as a NIR bioprobe.

Hydrothermal synthesis of brookite-type titanium dioxide was performed with excellent reproducibility using an aqueous NH 3 solution of a water-soluble citratoperoxotitanate (CPT) complex. X-ray diffraction confirmed that the brookite phase was formed by hydrothermal treatment of the CPT complex in NH 3 solution with a concentration of more than 6.5 wt%, whereas single phase anatase was obtained when distilled water without any additives was applied as the solvent. The aspect ratios of the obtained rod-like brookite particles increased from 5 up to 20 with an increase of the NH 3 concentration. Transmission electron microscopy and selected area electron diffraction measurements provided evidence that the growth of the brookite particles is along the c -axis. Hydrothermal treatment of the CPT complex at high NH 3 concentrations resulted in the formation of agglomerated brookite particles with unusual shapes, where many rod-like particles were branched around a somewhat longer central particle, and the side view of the agglomerated particles revealed two-dimensional crystal growth within a given restricted plane. The multi-needle agglomerate of particles was snowflake shaped. The reason for the formation of brookite with this unique morphology may be attributed to an intrinsic character of the CPT complex itself, although the mechanism is yet to be clarified.

Single-phase nanoparticles of brookite, a less common polymorph of TiO2 than rutile and anatase, were successfully synthesized using a water-soluble titanium–glycolate complex as the precursor and nanoparticle growth by an oleate-modified hydrothermal growth method. The synthesized particles were approximately 30 nm in size, had high crystallinity, and were highly dispersible in water. The morphology of the synthesized particles was a pseudocube surrounded mainly with four {210} and two {001} faces, accompanying truncation with small {111} facets. It is considered that the preferential absorption of oleate molecules on {210} and {001} faces resulted in the pseudocubic crystal shape.

Titanium dioxide thin films were prepared by using four water-soluble titanium complexes of titanium-lactate, tartalate, malate and salicylate complex solutions. The crystalline phases detected in the films were anatase. The surface microstructures of the four film samples were different in their grain sizes. Photocatalytic decomposition activity of the four films was almost the same, but their photoinduced hydrophilicities were different. The film prepared using titanium-salicylate complex exhibited lower hydrophilic conversion rate than the other films. Grain size and stress yielded to the film are considered to be important factors on the photoinduced hydrophilicity.

Since the method of performing displacement measurement and stress assessment of material by non-contact comes to capture the spotlight, study of the digital image correlation method which adopted the pattern-matching method for asking for displacement by deformation of a surface speckle pattern has been advanced. When the configuration for an analysis was settled in the rectangle and the square region, the whole-field mesh generation was also possible, but when it became a complicated configuration, the background etc. entered and mesh generation was affected. In order to solve such a problem, even if the object for an analysis was a complicated configuration, it aimed at generating a mesh automatically and obtaining appropriate analysis output in the displacement analysis and stress analysis using the generated mesh. In addition, the validity of the result was verified by the comparison with the finite element method. By this study, the convenience and availability of the digital image correlation method was improved remarkably, and it became clear to become a leading tool in health monitoring.

Water-soluble titanium complexes are attractive titanium sources for solution synthesis of titanium-based materials using water as a solvent due to their high stability in aqueous solution in wide range of pH, and have been made from expensive metal titanium ultrafine powder. In this study, TiCl4 and Ti(SO4)2 that are inexpensive reagents than metal titanium fine powder were chosen as starting materials. TiCl4 and Ti(SO4)2 were dropped into distilled water and large amount of NaOH solution was added here, then precipitates of Ti(OH)4 were obtained. Then precipitates were washed with distilled water and dissolved into mixed solution of H2O2 and NH3. And lactic acid as complexing agent was added to the solutions to obtain water-soluble titanium lactate complex solutions. These complex solutions generated no precipitate at pH 0 to 12 for 6 months. Yields of Ti in the both processes were 85 % and removal ratios of Cl- and SO42- ions were 99 and 93 %, respectively. MCO3 (M=Ca2+, Sr2+, Ba2+) were dissolved in the complex solution prepared from TiCl4, and the solution was dried and heated at 873 K for 5 h. Very fine and crystalline particles of CaTiO3, SrTiO3 and BaTiO3 were obtained by heating at 873 K in this solution method, while large particles of CaTiO3, SrTiO3 and BaTiO3 were obtained at 1273 K in solid-state reaction. Low temperature synthesis of titanium complex oxides by a new synthetic route of water-soluble titanium complex from titanium chloride and titanium sulfate as starting materials was successfully achieved.

We developed a new synthetic route of water-soluble complexes using TiCl4 and Ti(SO4)2 as starting materials. The yield of Ti and the removal rate of the Cl− ion were over 85 and 98%, respectively. The lactato titanium complex solution obtained by this new synthetic route remained stable for more than 3 months without any precipitation. Single-phase CaTiO3, SrTiO3, and BaTiO3 were synthesized from the lactato titanium complex by heating at 873 K for 5 h. The nano-structured CaTiO3, SrTiO3, and BaTiO3 particle sizes were 50, 30, and 30 nm in diameter, respectively, and smaller than those obtained by the solid-state method. We have succeeded in the synthesis of very fine particles of CaTiO3, SrTiO3, and BaTiO3 at a temperature 400 K lower than that required for the solid-state method.

We prepared NaTaO3 by hydrothermal method and solvothermal method. Na2Ta2O6 was obtained by hydrothermal treatment of water soluble tantalum complex and NaOH. On the other hand NaTaO3 was obtained by solvothermal treatment of TaCl5 and NaOH in methanol. Many samples were synthesized in various hydrothermal condition, however all samples were Na2Ta2O6 or amorphous. Primary particle size of samples obtained by solvothermal method was 10 nm. Primary particles aggregated and formed 20-50 nm secondly particles. Moreover, specific surface area of NaTaO3 synthesized by the solvothermal method was 109 m2/g. Therefore we succeeded in obtaining NaTaO3 fine particles with high specific surface area. NaTaO3 sample loaded NiO of 6 wt% produced H2 of 600 μmol/h. When solvothermal treatment time was extended from 5 hours to 10 hours and stirring in solvothermal treatment, water splitting activity of NaTaO3 was improved.

A new solution method that can be used to synthesize borate compounds was developed using citric acid and ethylenediamine. The conventional polymerizable complex method (polyester method) has a significant advantage in terms of homogeneity of the precursor, and it has been utilized in the synthesis of numerous oxide ceramics. However, it is very difficult to synthesize borate compounds by the conventional polymerizable complex method because boron reacts with the glycol that is necessary for the polymerization as polyester and is volatilized from the solution. In this paper, functional borate compounds such as YBO3:Eu3+, InBO3, and K3Ta3B2O12 were synthesized by the conventional polyester-type polymerizable complex method as well as the new solution method. In the polyester method, citric acid was dissolved in propylene glycol and the component metal salts were then dissolved in this solution. In the method that we propose in this paper, citric acid and ethylenediamine were dissolved in distilled water, and component metal salts were added to the solution. All solutions were heated at 403 K with stirring for the polymerization reaction to proceed, yielding polymer resins. The resins were heated to 723 K and powder precursors were obtained. The precursors were calcinated under various temperature conditions. In the case of YBO3:Eu3+, the formed product was Y2O3 by the polyester method due to volatilization of boron. On the other hand, single-phase YBO3:Eu3+ was synthesized by the new method. YBO3:Eu3+ synthesized by the method showed higher photoluminescence intensity than samples synthesized by a solid-state reaction method and the complex gelation method. Synthesis of single phase InBO3 and K3Ta3B2O12 was also successfully demonstrated by the method using a very small excess amount of H3BO3.

The growing significance of nanocrystalline inorganic functional materials in the fields of catalysis, electronics, and energy conversion together with the increasing demand of the society for safe...

Recently, several oxide-based phosphors with excellent luminescence properties have been reported. Especially, the deep-red emitting Ca1.2Eu0.8SiO4 has been prepared by the basis on crystal-site engineering, which shows an emission peak at 653 nm under excitation at 450 nm [1]. The emission wavelength of Ca1.2Eu0.8SiO4 is quite similar to those of commercial red-emitting CaAlSiN3:Eu2+ and Sr2Si5N8:Eu2+. The crystal structure of Ca2-x Eu x SiO4 is analogous to those of Sr2-x Eu x SiO4 and Ba2-x Eu x SiO4. Therefore, it is expected that the addition of large amounts of Eu2+ ions to Sr2-x Eu x SiO4 and Ba2-x Eu x SiO4 can also lead to large redshifts in their emission and excitation spectra. In this study, we prepared and characterized Sr2-x Eu x SiO4 and Ba2-x Eu x SiO4 with a high concentration of Eu2+ ions. In the case of Sr2-x Eu x SiO4, the emission peak was shifted from 585 nm for Sr1.9Eu0.1SiO4 to 611 nm for Sr1.2Eu0.8SiO4. On the other hand, in the case of Ba2-x Eu x SiO4, the emission peak was shifted from 513 nm for Ba1.9Eu0.1SiO4 to 545 nm for Ba1.2Eu0.8SiO4. The right-hand edges of the excitation spectra for both the samples were significantly shifted, by 40-55 nm, to longer wavelengths, allowing for excitation by blue light. The induction of large redshifts in the emission and excitation spectra of both samples could be attributed to the occupancy of Eu2+ ions in the polyhedra of Sr(2) or Ba(2) sites, which are smaller and more distorted than the Sr(1) or Ba(1) sites. These results indicate that Sr1.2Eu0.8SiO4 and Ba1.2Eu0.8SiO4 are suitable as red- and green-emitting phosphors for next-generation white-LED applications. [1] Y. Sato and M. Kakihana et al., Angew. Chem. Int. Ed. 53 (2014) 7756.

The thermoelectric properties of bismuth telluride (Bi2Te3) nanoplate thin films were estimated using combined infrared spectroscopy and first-principles calculation, followed by comparing the estimated properties with those obtained using the standard electrical probing method. Hexagonal single-crystalline Bi2Te3 nanoplates were first prepared using solvothermal synthesis, followed by preparing Bi2Te3 nanoplate thin films using the drop-casting technique. The nanoplates were joined by thermally annealing them at 250 °C in Ar (95%)–H2 (5%) gas (atmospheric pressure). The electronic transport properties were estimated by infrared spectroscopy using the Drude model, with the effective mass being determined from the band structure using first-principles calculations based on the density functional theory. The electrical conductivity and Seebeck coefficient obtained using the combined analysis were higher than those obtained using the standard electrical probing method, probably because the contact resistance between the nanoplates was excluded from the estimation procedure of the combined analysis method.

High-purity hexagonal bismuth telluride (Bi2Te3) nanoplates were prepared by a solvothermal synthesis method, followed by the fabrication of nanoplate thin films by the drop-casting technique. The Bi2Te3 nanoplates exhibited a single-crystalline phase with a rhombohedral crystal structure. The nanoplates had a flat surface with edge sizes ranging from 500 to 2000 nm (average size of 1000 nm) and a thickness of less than 50 nm. The resulting Bi2Te3 nanoplate thin films were composed of well-aligned hexagonal nanoplates along the surface direction with an approximate film thickness of 40 µm. To tightly connect the nanoplates together within the thin films, thermal annealing was performed at different temperatures. We found that the thermoelectric properties, especially the Seebeck coefficient, were very sensitive to the annealing temperature. Finally, the optimum annealing temperature was determined to be 250 °C and the Seebeck coefficient and power factor were −300 µV/K and 3.5 µW/(cmK2), respectively.

A panel of new stable and water soluble complexes of titanium (IV) with natural hydroxy-carboxylic acids such as citric, tartaric, lactic or glycolic acid as ligands was developed. A typical structure of these complex ions includes a peroxo-group, and a hydroxy-carboxylic acid molecule attached to the metal ion by carboxylic and hydroxylic groups to form stable species. The tight coordination and negative charge of complex ions are responsible for stability of these new compounds in water solutions in a wide range of temperatures and pH. Use of natural non-toxic ligands and ammonium as counterions make such titanium compounds convenient reagents for "green" synthesis of titanium containing materials by aqueous solution methods.The architecture of titanium complexes includes structural motifs of different polymorphic forms of TiO2, which allows for application of these compounds as building blocks (tecton) for synthesis of titania with different crystal structures by a simple hydrothermal processes. In this way anatase, rutile, TiO2(B) and brookite were prepared in a reproducible and highly selective way. For the first time TiO2(B) and brookite were synthesized as single phase nano-crystals by a "one-pot" hydrothermal process, and their outstanding photo-catalytic activities were revealed.

Nanocrystalline brookite titanium oxide was prepared by hydrothermal treatment of a water-soluble titanium complex with ethylenediaminetetraacetic acid (EDTA). In this work, we examined the effect of synthesis conditions such as reaction time, titanium concentration and solution pH on the brookite phase formation and its photocatalyitic performance. It was found that hydrothermal treatment of the titanium complex may yield anatase and brookite phases, and their ratio can be varied depending on titanium concentration. Single phase brookite could be prepared when titanium concentration in the starting solution was higher than 0.25 mol/dm3, while lower concentration favors formation of anatase. Remarkably, brookite could be synthesized from the Ti-EDTA complex in the wide range of pH including both acidic and basic media. The samples prepared from Ti-EDTA complex demonstrated higher photocatalytic activity in terms of NO gas decomposition than the brookite powders synthesized from Ti-glycolate complex or commercial TiO2 photocatalyst P25. Higher photocatalytic activity of powders obtained from Ti-EDTA complex aqueous solution is explained by higher surface area of smaller but well-crystallized brookite particles that can be achieved when this new titanium complex is employed.

Titanium dioxide (TiO 2 )(B), one of metastable polymorphs of TiO 2 was prepared by hydrothermal reaction of glycolato peroxotitanium complex ([Ti 4 (C 2 H 2 O 3 ) 4 (C 2 H 3 O 3 ) 2 (O 2 ) 2 ] 6− ) in the presence of H 2 SO 4 as an additive. Characterization by X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM) revealed that the obtained powders were single-phase TiO 2 (B) with rod-like shape. Particle size and aspect ratio of TiO 2 (B) can be controlled by post-synthetic hydrothermal crystal growth (PHCG) of the as-prepared powder sample.

The metastable phase of TiO2(B), one of the polymorphs of titanium dioxide (TiO2), was prepared by a hydrothermal treatment of a titanium glycolate complex ([Ti4(C2H2O3)4(C 2H3O3)2(O2)4O2]6-) at 473 K for 1-72 h in the presence of H2SO4. Characterization by X-ray diffraction (XRD) and transmission electron microscopy (TEM) revealed that the obtained samples were composed of single phase TiO2(B) and the particles had plate-like morphology. After post-synthetic hydrothermal crystal growth (PHCG) applied to the as-prepared sample, thicker plate-like shaped particles were obtained. The photocatalytic activities of the samples obtained by the hydrothermal treatment and after the subsequent PHCG were evaluated in terms of methanol decomposition.

K3Ta3B2O12 is photocatalyst that exhibit relatively high water splitting activity without co-catalyst, was synthesized by various solution methods. Obtained samples were characterized by X-ray diffraction. Samples synthesized by complex gelation method and polyamide-type polymerizable complex method ware single phase K3Ta3B2O12. Sample synthesized by complex gelation method was tested for water splitting activity, and this sample has little water splitting activity without co-catalyst. When NiO 0.5 wt% as co-catalyst was loaded to samples, hydrogen generated 1600 μmol/h.

Ba2Ti9O20 has a similar structure to Hollandite structure, and has high ionic conductivity because of its tunnel structure. It is used as electronic material in high frequency devices due to its ferroelectricity and the small temperature coefficient. The single phase of Ba2Ti9O20 is hard to obtain because only the small deviations from the required stoichiometry lead to formation of impurity phases having close chemical composition. In this study we prepared precursor of Ba2Ti9O20 by complex gellation method in which citratoperoxititanic acid tetranuclear complex was used as a Ti source. The homogeneous precursor was obtained by mixing the Ti complex, Ba(CH3COO)2, and H3BO3 (as a flux) in aqueous solution. The obtained precursor was then heat-treated at 1,273 K, which is 230 K below the temperature needed for the conventional solid-state reaction method, and the single phase of Ba2Ti9O20 was formed. The crystallite size of the prepared powder was less than 100 nm that is desirable for ferroelectric materials.

Nanowhiskers of rutile-type titanium dioxide (TiO2) were synthesized by a simple hydrothermal treatment of a water-soluble titanium–glycolate complex at 473 K. The aspect ratio of the obtained rutile particles could be controlled by changing the concentration of the glycolic acid additive in the starting aqueous solution of the titanium complex. According to high-resolution transmission electron microscopy, whisker-like nanoparticles grow along the c-axis of rutile, the side facets of which are (110), (−110), (1–10), and (−1–10). Glycolic acid controls promotion of the rutile particles in the specified direction due to its preferred adsorption on the titanium-rich facets. Evaluation of the photocatalytic activity of the synthesized TiO2 was performed in terms of decomposition of oxalic acid in an aqueous system under ultraviolet irradiation. It turned out that this particular whisker-like shape is responsible for the tremendous enhancement of rutile photocatalytic activity, and even rutile samples with low surface area demonstrated photocatalytic performance comparable with one of the best nanosized anatase photocatalytic materials. Therefore, it can be concluded that the (110) rutile facet plays an important role in the photocatalytic oxidation reaction, and that it exhibits higher photocatalytic activity than the (001) facet in the decomposition of oxalic acid.

The K3Ta3B2O12 photocatalytic material for water splitting was prepared by an aqueous solution-based process using a novel water soluble Ta-peroxolactate complex. Use of water as a processing solvent is essential to prevent formation of volatile boron compounds and to synthesize the stoichiometric single phase material by a solution technique. Photocatalytic activity of K3Ta3B2O12 for water splitting was the highest when a stoichiometric amount of lactic acid (LA) with Ta:La = 1:2 was used for preparation of the Ta-peroxo lactate complex. Additionally, activities of K3Ta3B2O12 in the photocatalytic water splitting have been improved when NiO was used as a co-catalyst. The highest photocatalytic hydrogen and oxygen evolution rates exhibited by the materials prepared in this work were H2: 392 μmol/h and O2: 192 μmol/h.

We prepared two new water-soluble complexes of titanium with L-serine and L(-)-threonine amino acids. It was demonstrated that these compounds can be outstanding precursors for a hydrothermal synthesis of nanocrystalline TiO2. The obtained powders were composed of anatase or a mixture of anatase and brookite. Particles diameters were ~10 nm and BET surface areas were ~120 m2/g. The powder composed of anatase and brookite synthesized by hydrothermal treatment of the titanium-threonine complex aqueous solution at 200°C for 24 h exhibited higher photocatalytic activity for oxalic acid oxidation than the commercial anatase-type TiO2 photocatalyst (ST-01, Ishihara Sangyo Kaisya, average diameter: 7 nm, specific surface area: 257.5 m2/g).

It was demonstrated that brookite-type titanium oxide can be directly synthesized by the hydrothermal treatment of novel water-soluble titanium complexes under basic conditions in the presence of an additive. In particular, single-phase brookite was synthesized from the titanium–glycolate complex at a pH of about 10 in the presence of excess NH3 aqueous solution or ethylenediamine, and powder thus obtained consisted of rod-like nanosized particles. It was suggested that the structures of titanium complexes are important for the formation of brookite.

Hydrothermal treatment of a series of water-soluble titanium complexes resulted in the formation of TiO2. Rutile, anatase or a mixture of both can be synthesized by varying the ligands. The titania obtained was composed of nano-sized particles with large specific surface areas. These TiO2 powders exhibited high photocatalytic activity for NO x decomposition. In particular, they demonstrated higher activity than P25 (Degussa) under visible-light irradiation.

We report the first successful synthesis of TiO2(B) nanoparticles by a one-step hydrothermal process. The process was performed under acidic conditions in a 0.59 M H2SO4 solution at 160 °C for 24 h...

Nanoparticles of brookite titanium oxide were prepared by microwave-assisted hydrothermal (MH) method at 200°C (heating time 5 min) for 0-60 minutes starting from the titanium peroxo glycolate complex in basic solution. The effect of microwave heating on the morphology of the brookite particles was examined. The samples were characterized by X-ray diffraction (XRD), Raman spectroscopy and transmission electron microscopy (TEM). It was found that all powders were composed of single phase brookite and contained two different types of particles. The activity in photodecomposition of oxalic acid by the samples prepared using MH method was higher than activities of brookite nanoparticles synthesized by the conventional hydrothermal method.

Highly crystalline titania nano-particles were synthesized by hydrothermal method using novel stable water-soluble titanium complexes. It was confirmed that single phase anatase, rutile and brookite, which can be rarely synthesized as a single phase, can be obtained by varying the ligand in the complex and pH of the aqueous solution. TEM observations and BET specific surface area measurements had shown that these samples consisted of nanosized particles of 5~200 nm and had high specific surface areas of 25~150 m2/g. According to UV-visible diffuse reflectance spectra, these titania samples absorbed light in the visible region (λ > 400 nm). Photocatalytic activities in NO oxidation reaction exhibited by synthesized titania powders under the irradiation by UV- visible light were higher than the activity of the commercial TiO2 photocatalyst P25 (Degussa). Especially, under illumination by only visible light of above 510 nm wavelength, photocatalytic activity of the obtained specimens exceeded that of P25 more than four times. We also clearly demonstrated that single phase brookite had high photocatalytic activity for NO oxidation.

Single phase rutile was synthesized by a simple hydrothermal treatment of an aqueous titanium glycolate complex solution at 200°C for 24 h. The obtained sample was composed of 50×150 nm rod-like nanoparticles. The aspect ratio of the prepared particles could be controlled by adding glycolic acid or lactic acid to reaction solution. Up to 30×2000 nm whisker-like particles could be obtained. The hydroxycarboxylic acids favor development of specific crystal facets and allow to control the aspect ratio of the rutile nanoparticles. We also proposed a model, which explains formation of anatase and rutile, and disappearance of anatase particles during rutile crystals development.

The 5′-AMP-activated protein kinase (AMPK) functions as a cellular energy sensor. 5-Aminoimidazole-4-carboxyamide-1-β-D-ribofranoside (AICAR) is a chemical activator of AMPK. In the liver, AICAR suppresses expression of the phosphoenolpyruvate carboxykinase (PEPCK) gene. The rat enhancer of split- and hairy-related protein-2 (SHARP-2) is an insulin-inducible transcriptional repressor and its target is the PEPCK gene. In this study, we examined an issue of whether the SHARP-2 gene expression is regulated by AICAR via the AMPK. AICAR increased the level of SHARP-2 mRNA in H4IIE cells. Whereas an AMPK inhibitor, compound-C, had no effects on the AICAR-induction, inhibitors for both phosphoinositide 3-kinase (PI 3-K) and protein kinase C (PKC) completely diminished the effects of AICAR. Western blot analyses showed that AICAR rapidly activated atypical PKC lambda (aPKCλ). In addition, when a dominant negative form of aPKCλ was expressed, the induction of SHARP-2 mRNA level by AICAR was inhibited. Calcium ion is not required for the activation of aPKCλ. A calcium ion-chelating reagent had no effects on the AICAR-induction. Furthermore, the AICAR-induction was inhibited by treatment with an RNA polymerase inhibitor or a protein synthesis inhibitor. Thus, we conclude that the AICAR-induction of the SHARP-2 gene is mediated at transcription level by a PI 3-K/aPKCλ pathway.

Cyanobacteria produce numerous volatile organic compounds (VOCs), such as β-cyclocitral, geosmin, and 2-methylisoborneol, which show lytic activity against cyanobacteria. Among these compounds, only β-cyclocitral causes a characteristic color change from green to blue (blue color formation) in the culture broth during the lysis process. In August 2008 and September 2010, the lysis of cyanobacteria involving blue color formation was observed at Lake Tsukui in northern Kanagawa Prefecture, Japan. We collected lake water containing the cyanobacteria and investigated the VOCs, such as β-cyclocitral, β-ionone, 1-propanol, 3-methyl-1-butanol, and 2-phenylethanol, as well as the number of cyanobacterial cells and their damage and pH changes. As a result, the following results were confirmed: the detection of several VOCs, including β-cyclocitral and its oxidation product, 2,2,6-trimethylcyclohexene-1-carboxylic acid; the identification of phycocyanin based on its visible spectrum; the lower pH (6.7 and 5.4) of the lysed samples; and characteristic morphological change in the damaged cyanobacterial cells. We also encountered the same phenomenon on 6 September 2013 in Lake Sagami in northern Kanagawa Prefecture and obtained almost the same results, such as blue color formation, decreasing pH, damaged cells, and detection of VOCs, including the oxidation products of β-cyclocitral. β-Cyclocitral derived from Microcystis has lytic activity against Microcystis itself but has stronger inhibitory activity against other cyanobacteria and algae, suggesting that the VOCs play an important role in the ecology of aquatic environments.

Multicentric study was conducted to evaluate the efficacy of glimepiride in the oral hypoglycemic agents therapy of type 2 diabetic patients treated with glibenclamide so far, and to claim an adequate use of this new generation sulfonylurea. In 66 diabetic outpatients, glibenclamide was switched to glimepiride. After 6 months' therapy, a significant reduction in fasting plasma IRI was observed in relatively hyperinsulinemic patients. In addition, weight reduction was achieved in patients with insulin resistance during this study. These findings suggest that glimepiride improves insulin resistance in hyperinsulinemic patients treated with glibenclamide. Also, glimepiride is favored especially for overweight, insulin-resistant patients inadequately controlled by glibenclamide.

Familial hypokalemic periodic paralysis is an autosomal dominant genetic muscle disease characterized by periodic attacks of muscle weakness associated with a decrease in serum potassium. There are two major missense mutation sites in the calcium channel alpha1 subunit (CACNA1S) gene in these patients. We recently encountered a 13-year-old Japanese boy who had collapsed following exercise and was found to have a low serum potassium level. Clinical and genetic studies including exploration of his family tree proved that he and his maternal relatives had the disease with the missense mutation, Arg528His (CGC --> CAC). However, his mother and grandmother had no symptoms of the disease, indicating reduced penetrance in female carriers. Sexual difference in the penetrance of this disease and the association between the clinical symptoms and the types of genetic defects are discussed.

Upconversion (UC) phosphors comprising Er3+/Yb3+ codoped rare-earth complex oxides, RExTayOz and RExNbyOz (RE = Y, La, or Gd), were synthesized via the gelable citrate complex method, and their UC emission properties were compared. This led to the discovery of an intense green-emitting UC phosphor, YTa7O19:Er3+/Yb3+, which is the first example of a YTa7O19 UC phosphor host material. Green UC emission obtained using optimum Er3+ and Yb3+ content was 20 times stronger than that obtained using a Y2O3 host.

A polyoxovanadate–surfactant hybrid layered crystal was synthesized by using decyltrimethylammonium (C10) cation. The hybrid crystal with a formula of (C10)4[H2V10O28]·8H2O (C10–V10) contained dipr...

It has been well-known that silicon-based nitride phosphors such as CaAlSiN3:Eu2+ and Sr2Si5N8:Eu2+ possess excellent red-light emission when excited by blue-light region. However, preparation of such silicon-based nitride phosphors in pure form should be needed to sinter precursor powders under high pressure and temperature conditions. On the contrary, Eu2+-activated silicates with alkaline earth ions have been reported as high efficient phosphors. Such silicon-based oxide phosphors in pure form can be easily obtained by simple preparation techniques without any critical conditions mentioned above. Therefore, productivity and production cost for silicate phosphors are advantageous for the commercial production of red phosphors. We have reported red-emitting Ca1.2Eu0.8SiO4 phosphors excited by blue light region.1) The wavelength at the maximum emission of Ca1.2Eu0.8SiO4 phosphors was 650nm.1) We have recently discovered new red-emitting Ca3ZrSi2O9:Eu2+ phosphors with high Eu2+ concentration excited by near-UV and blue-light region. Ca3ZrSi2O9 activated by low Eu2+ concentrations (Eu2+: 1 mol%) exhibited a green emission at 530 nm. However, with increasing Eu2+ concentration to 10 mol%, Ca3ZrSi2O9:Eu2+ phosphors exhibited red emission peaking at 650 nm while the green emission disappeared. Based on the crystal structure data of Ca3ZrSi2O9, there were three Ca sites in Ca3ZrSi2O9, where Eu2+ ions were occupied.2) Two of the Ca sites were smaller than another Ca site. We presume that emission at 530 nm from Eu2+ occupying the large Ca site was not observed owing to Eu2+ concentration quenching, as well as reabsorption of the green emission light from Eu2+ at the large Ca site by Eu2+ at the two small Ca sites. Thus, the deep-red emission of Ca3ZrSi2O9:Eu2+ phosphors observed is considered to be emission from Eu2+occupying these small Ca sites. 1) Y. Sato, H. Kato M. Kobayashi, T Masaki, D. H. Yoon and M. Kakihana, Angew. Chem. Int. Ed. 53(2014) 7756. 2) J. R. Plaister, J. Jansen, R. G. de Graaff, D. J. W. IJdo, J. Solid State Chem. 115 (1995) 464.