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Background: We previously reported changes of body composition determined by dual-energy X-ray absorptiometry after treatment with ipragliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor. In that study, mean body weight was decreased by 3.5 kg (4.3% of the baseline value) after ipragliflozin treatment at 50 mg/day, with fat mass and lean mass showing similar reductions of 1.7 and 1.8 kg, respectively. A long-term decrease of lean mass in patients treated with SGLT2 inhibitors may be associated with loss of skeletal muscle, which could potentially have an impact on quality of life. Methods: In this post hoc analysis, we investigated whether changes of body composition were influenced by other medications for diabetes in 20 patients (11 men and nine women) who received ipragliflozin for 24 weeks. Results: When we divided the patients into two subgroups with or without metformin treatment, fat mass showed a significant decrease in the ipragliflozin + metformin subgroup and a significantly greater decrease compared to the ipragliflozin subgroup (2.0 kg; 95% confidence interval (CI): 0.1 - 3.9; P = 0.038). Lean mass was significantly decreased in the ipragliflozin subgroup, but the decrease showed no significant difference from that in the ipragliflozin + metformin subgroup (1.9 kg; 95% CI: -4.1 - 0.3; P = 0.087). No significant differences of body composition changes were observed with other antidiabetic agents. Conclusions: More desirable weight reduction due to preferential fat loss and less muscle loss may be achieved by combining an SGLT2 inhibitor with metformin. J Clin Med Res. 2019;11(4):297-300 doi: https://doi.org/10.14740/jocmr3785

Context In adrenal venous sampling (AVS) for patients with primary aldosteronism (PA), apparent bilateral aldosterone suppression (ABAS), defined as lower aldosterone/cortisol ratios in the bilateral adrenal veins than that in the inferior vena cava, is occasionally experienced. ABAS is uninterpretable with respect to lateralization of excess aldosterone production. We previously reported that ABAS was not a rare phenomenon and was significantly reduced after adrenocorticotropic hormone (ACTH) administration. Objective To validate the effects of ACTH administration and adding sampling positions in the left adrenal vein on the prevalence of ABAS in the larger Japan Primary Aldosteronism Study. Patients The data from 1689 patients with PA who underwent AVS between January 2006 and October 2016 were studied. All patients in the previous study, the West Japan Adrenal Vein Sampling study, were excluded. Outcome Measurements The prevalence of ABAS was investigated at two sampling positions in the left adrenal vein, the central vein and the common trunk, without and with ACTH administration. Results The prevalence of ABAS with ACTH administration was significantly lower than that without ACTH administration [without ACTH vs with ACTH: 79/440 (18.0%) vs 45/591 (7.6%); P < 0.001]. With ACTH administration, the prevalence of ABAS was not different between the sampling position, at the central vein and at the common trunk [33/591 (5.6%) vs 32/591 (5.4%); P = 1.00]. Conclusions The effectiveness of ACTH administration for the reduction of ABAS in AVS regardless of the sampling position in the left adrenal vein was confirmed in the larger cohort., We validated the effect of ACTH administration on resolving ABAS, defined as lower aldosterone/cortisol ratios in the bilateral adrenal veins than that in the inferior vena cava.

Monoterpene alcohols (MTAs) are characteristic flavour-imparting compounds in sweet potato shochu (Japanese distilled spirit) that are liberated following hydrolysis by specific enzymes during fermentation. In the present study, we evaluated the effect of an exogenously added diglycoside-specific β-glycosidase (β-primeverosidase) on aroma formation during shochu brewing using various sweet potato species to address whether MTAs are predominantly present as diglycosidic precursors in raw materials. The results showed that the amount of MTAs produced from enzyme-treated mash was dramatically increased by 2- to 9-fold compared with untreated controls, and the increase varied with sweet potato species. In addition, levels of methyl salicylate, 1-octene-3-ol and ethyl benzoate were also elevated by enzyme treatment. These results indicate that a large amount of MTAs and other volatile aroma compounds are stored in the form of disaccharide β-glycosides such as β-primeverosides in sweet potato. This enzyme may therefore be useful for controlling aroma formation during shochu manufacturing, and may ultimately contribute to diversifying shochu quality.

Objectives Current clinical guidelines of primary aldosteronism recommend adrenalectomy (AdX) for unilateral primary aldosteronism based on the studies showing the potential superiority of AdX over the medical treatment. However, since most medically treated cases consisted of bilateral primary aldosteronism and all surgically treated cases consisted of unilateral primary aldosteronism, the different subtype of primary aldosteronism could be a bias for their effects. This study compared the effects of AdX and medical therapy in patients with unilateral primary aldosteronism confirmed by adrenal vein sampling. Methods Of the 339 patients with unilateral primary aldosteronism in the Japan Primary Pldosteronism Study data base, unilateral AdX and treatment with mineral corticoid receptor antagonists (MRAs) was done in 276 patients (AdX group) and in 63 patients (MRAs group), respectively. The effects were compared by the clinical (improvement of blood pressure) and biochemical outcomes (improvement of hypokalemia). Results At baseline, use of potassium replacement, plasma aldosterone concentration, aldosterone-to-renin ratio, estimated glomerular filtration rate, and prevalence of adrenal mass on imaging were higher in the AdX group than in the MRAs group. At 6 months after commencement of specific treatment for primary aldosteronism, clinical outcome and biochemical outcome in the AdX group were superior than those in the MRAs group. The difference of the outcome between the two groups were the case even after adjusting for the different clinical backgrounds in the two groups before the specific treatment. Conclusion Our study provides evidence that AdX is the first choice of treatment in the patients with unilateral primary aldosteronism in terms of clinical and biochemical outcome.

Yeast histone deacetylases (HDAC) affect the production of alcoholic beverages. In this study, we evaluated the sake fermentation characteristics when using HDAC gene-disrupted yeast strain Kyokai No. 701. Flavor components of the sake product were significantly changed. RPD3 or HDA1 disruption increased twofold the amount of isoamyl acetate, and isoamyl alcohol levels also increased in the rpd3Δ strain. To determine the contribution of Rpd3L and Rpd3S complexes to sake characteristics, a gene responsible for Rpd3L and/or Rpd3S formation was also disrupted. Disruption of DEP1 or SDS3 that is an essential component of Rpd3L led to increased isoamyl alcohol production similar to that of the rpd3Δ strain, but the efficiency of isoamyl alcohol esterification was not affected. In addition, Rpd3 and Hda1 may regulate the responsiveness to oxygen in isoamyl acetate production. We conclude that HDAC genes regulate the production of flavor components during sake fermentation. Abbreviations: HDAC: Histone deacetylase; HAT: histone acetyltransferase; K701: sake yeast Kyokai No. 701; PCR: polymerase chain reaction; HPLC: high performance liquid chromatography; E/A: Ester/Alcohol; BCAA: branched chain-amino acid; Atf: alcohol acetyltransferase. Yeast Rpd3S and Hda1 complexes repress iAmOAc production. Rpd3L reduces iAmOH via repression of ILV2, 3, and 5, and it also regulates organic acids production.

Promoter shutoff is a general method for analyzing essential genes, but in the fungus Aspergillus oryzae, no tightly repressed promoters have been reported. To overcome the current limitations of conditional promoters, we examined sorbitol- and galactose-responsive genes using microarrays to identify regulatable genes with only minor physiological and genetic effects. We identified two sorbitol-induced genes (designated as sorA and sorB), cloned their promoters, and built a regulated egfp and brlA expression system. Growth medium-dependent enhanced green fluorescence protein (EGFP) fluorescence and conidiation were confirmed for egfp and brlA under the control of their respective promoters. We also used this shutoff system to regulate the essential rhoA, which demonstrated the expected growth inhibition under repressed growth conditions. Our new sorbitol promoter shutoff system developed can serve as a valuable new tool for essential gene analyses of filamentous fungi.

Polysilsesquioxanes (PSQs) possessing 3-methacryloxypropyl groups as an organic moiety of the side chain were synthesized by sol–gel condensation copolymerization of the corresponding trialkoxysilanes. The ultra-thin PSQ film with a radical initiator and a cross-linking agent was prepared by a spin-coating method, and the film was cured integrally at low temperatures of less than 120 °C through two different kinds of polymeric reactions, which were radical polymerization of vinyl groups and sol–gel condensation polymerization of terminated silanol and alkoxy groups. The obtained PSQ film showed the almost perfect solubilization resistance to acetone, which is a good solvent of PSQ before polymerization. It became clear by atomic force microscopy observation that the surface of the PSQ film was very smooth at a nano-meter level. Furthermore, pentacene-based organic field-effect transistor (OFET) with the PSQ film as a gate insulator showed typical p-channel enhancement mode operation characteristics and therefore the ultra-thin PSQ film has the potential to be applicable for solution-processed OFET systems.

Organic thin-film transistor (OTFT) memory devices were fabricated with nanocrystal carbon (nc-C) dots incorporated into the pentacene/oxide interface in the active layer. The nc-C dots were arranged precisely in order on the OTFT channel region by a focused ion beam (FIB) technique using low-energy Ga + ions and phenanthrene as the carbon source. The structural information of nc-C dot arrays was obtained by scanning ion microscopy (SIM) and atomic force microscopy (AFM). These images indicate that the nc-C dot array was successfully formed on the oxide layer. The density of the two-dimensional nc-C dots was 1.3-1.5A—108 cm-2. The current-voltage (I-V ) characteristics showed that the OTFTs exhibit memory behavior upon the application of forward and reverse gate bias stresses. Depending on the polarity of gate bias, write and erase modes were induced, and a maximum threshold voltage shift I”Vth of 0.97 V was obtained. © The Surface Science Society of Japan.

Organic memory-transistor devices were fabricated from pentacene-based organic thin-film transistors (OTFTs) with a fullerene layer. The current-voltage (I-V) characteristics show that the fabricated OTFTs exhibit a unipolar property with p-channel characteristics. The fabricated OTFTs devices exhibit a threshold voltage shift upon the application of positive and negative bias. Under the effect of positive bias, the on state was induced and a ΔVth = 12.9 V was obtained. Meanwhile, the threshold voltage was reversibly shifted by ΔVth = 9.1 V under the effect of negative bias and the off state was induced. Upon the effect of bias, the carrier mobility of fabricated OTFTs is almost similar in both on and off states. Pentacene-based OTFTs without a fullerene layer for memory effect was demonstrated for comparison. The memory effect is mainly attributed to the fullerene layer. [DOI: 10.1380/ejssnt.2009.808]

Organic semiconductor nonvolatile memory devices were successfully fabricated from organic thin-film transistors (OTFTs) embedded with nanocrystal carbon (nc-C) dots incorporating pentacene as an active layer. The nc-C dots were arranged in the channel region by a focused ion beam (FIB) technique using a precursor of low energy Ga+ ions and a carbon source. The formation and morphology of nc-C dot arrays were investigated using a scanning ion microscopy (SIM) and atomic force microscopy (AFM), respectively. The SIM and AFM images show that the nc-C dot array was successfully grown on the SiO 2 layer. The density of the two-dimensional nc-C dots was 5 x 10 9 cm-2. The current-voltage (I - V) characteristics at room temperature show that the fabricated OTFTs exhibit a memory effect upon the application of forward and reverse bias. Under the effect of gate bias, on and off states were induced and a threshold voltage shift (I”Vth = 0.23 V) was obtained. The charge carrier mobility (I¼) of the OTFTs is similar in both on and off states. The memory effect was attributed to the nc-C dots in the pentacene-dielectric interface. © 2009 The Surface Science Society of Japan.

Organic thin film transistors (OTFTs) using substituted polyacetylenes which have a helical form were fabricated. Substituted polyacetylenes soluble to various organic solvents were obtained using a rhodium complex as the stereoregular polymerization catalyst of the substituted acetylenes. The polymer thin films were formed by spin coating method. Poly(2-ethynylthiophene) and poly(3-ethynylthiophene) bearing a thiophene ring as the side-chain is operated at p-type semiconductor and the maximum field-effect mobility of the P2ET and P3ET OTFT is estimated at 4.3×10-3 and 6.7×10-3cm2/Vs respectively. [DOI: 10.1380/ejssnt.2009.767]

Poly-3-hexylthiophene (P3HT) thin films were investigated by X-ray diffraction (XRD) and electron spin resonance (ESR) to reveal the film structure and molecular organization. The XRD data showed a diffraction pattern with a plane separation between the planes containing thiophene rings of 16.0 A. Comparison between the XRD patterns of powder and thin films of P3HT suggests that the main chains are folded on the substrate. Angular variation of the line position (g-value) of ESR spectra revealed that thiophene ring of P3HT orients along the substrate normal axis. The ESR linewidth varied by the angular rotation, indicating the one-dimensional spin–chain interactions in the P3HT thin films with a linear network of spin–chains. An organic thin-film transistor (OTFT) with P3HT film as a channel layer was then demonstrated. The P3HT films showed conducting characteristics with holes as carriers. The OTFTs indicated a field-effect mobility of 4.93 × 10− 3 cm2/Vs and an on/off ratio of 73 in the accumulation mode.

X-ray diffraction (XRD) data shows lattice planes with a spacing of 12.8 A for copper phthalocyanine (CuPc) thin films. Comparison between the XRD patterns of CuPc powder and thin films suggests that the molecules are oriented along the (100) lattice plane nearly perpendicular to the substrate. The XRD data of the perfluorinated phthalocyanine (F16CuPc) thin film indicate a similar structure to that of CuPc, but with a wider lattice spacing of 14.6 A. Angular variations of the line position (g-value) of ESR spectra reveal tilt angles of 39 and 34° for the CuPc and F16CuPc thin films, respectively, and the same deviation angle of 24°. This indicates a cone-shaped orientation of CuPc and F16CuPc with similar tilt and deviation angles. The ESR linewidths of both films show angular variation, indicating one-dimensional spin-chain interactions in both the CuPc and F16CuPc thin films. Organic thin-film transistors (OTFTs) with CuPc and F16CuPc films are tested for their suitability as channel layers. The OTFTs with a CuPc film exhibit conduction with holes as carriers, and have a field-effect mobility of 2.6 ×10-5 cm2 V-1 s-1 and an on/off ratio of 10 in the accumulation mode. The OTFTs with F16CuPc films exhibit conduction with electrons as carriers (n-type), and have a field-effect mobility of 2.0 ×10-4 cm2 V-1 s-1 and an on/off ratio of 2.4 ×104 in the accumulation mode.

We identified three types of acid phosphatase (ACP-I, ACP-II, and ACP-III) produced by Aspergillus oryzae in a submerged culture using only phytic acid as the phosphorous substrate. The optimum pH for the activities of the three enzymes was in the range of 4.5 to 5.5. Analysis of the substrate specificities of these enzymes revealed that ACP-I and ACP-III were acid phosphatases, and ACP-II was a phytase. These enzymes were produced during different periods of mycelial growth: ACP-II was produced during the early phase of cultivation (around 24 h), and ACP-I was produced between 24 to 72 h. ACP-III was detected after the production of ACP-I and ACP-II had ceased. The release of phosphate from phytic acid was expected to be due to the cooperative hydrolysis of these enzymes.

Four cellulose-degrading enzymes were identified in a solid-state culture of Aspergillus oryzae. The three major enzymes were purified and named Cel-1, Cel-2, and Cel-3, respectively. The molecular weights were determined to be 62, 120, and 34 kDa, respectively. The optimum temperature of Cel-3 activity was higher than that of the other enzymes. An acidic pH was found to be more suitable for Cel-1 activity than for the other enzymes, and Cel-3 was more stable under acidic conditions than the other two. These properties and the results of a protein homology search for N-terminal amino acid sequences suggest that Cel-1 and Cel-3 correspond to the previously isolated endo-1,4-beta-glucanase CelB and CelA, respectively. The analysis of substrate specificity suggested that Cel-2 is likely to be beta-glucosidase. The effect of Cel-1, Cel-2, and Cel-3 on the sake mash fermentation was determined and it was found that Cel-2 markedly improved material utilization and alcohol yield in sake mash fermentation.

The production of cellulose- (CEL), xylan- (XYL), and pectin-degrading enzymes (PEC) by a koji mold, Aspergillus oryzae, was studied, and their contributions to the maceration of the rice endosperm cell wall were investigated with regard to the utilization of available rice in the sake mash. The sake koji mold showed higher CEL and XYL productivities, whereas the miso and soy sauce koji molds showed higher PEC productivity. Statistical analyses indicated that CEL and XYL contribute predominantly and synergistically to the maceration of the rice endosperm cell wall. A. oryzae produced at least three kinds of CEL (Cel-1, 2, 3) and two kinds of XYL (Xyl-1, 2) when cultured in a wheat bran medium. In the solid-state culture, the production of Cel-3 and Xyl-2 was markedly stimulated by decreasing the moisture content of the solid substrate, although the production levels of Cel-1 and Xyl-1 were almost the same. These data suggest that the production of Cel-3 and Xyl-2 is strongly influenced by culture conditions, and that water activity is one of the dominant factors in the regulation of their production.

Several new types of cerulenin-resistant mutants of sake yeast were isolated. These mutants showed respiratory deficiency and could grow on media containing a higher concentration of antibiotics than could the parent. Sakes brewed by the mutants produced less succinate than by both the parent yeast and the mutants with respiratory deficiency induced by ethidium bromide. In addition, the acidity of these mutants was decreased. Since low acidity is favourable in both sake and wine, these mutants might be applicable for both sake and wine brewing.

The high phytase producing mutant of Aspergillus oryzae (KL-38) previously isolated was employed for koji making, and the produced koji rice then supplied for sake brewing. The alcohol fermentation was improved compared to that with the parent strain (A. oryzae BP-1). The effects of two phytase isozymes (Phy I and Phy II) produced by A. oryzae on yeast growth and inorganic phosphate liberation were investigated using a synthetic medium containing phytic acid as a sole phosphate source. Yeast growth and the liberation of inorganic phosphate were both enhanced by the combination of Phy I and Phy II at a ratio of 1 to 3, which was compatible with the production ratio in KL-38. Based on these results, phytase plays important role in sake brewing, and that the maximum inorganic phosphate liberation from phytic acid can be obtained by a suitable combination of Phy I and Phy II.

An antibiotic-resistant strain of Saccharomyces cerevisiae was isolated from shochu yeast. Three mutants were used for shochu brewing and gave higher ethanol productivities than the parent. The mutants were resistant to cycloheximide, cerulenin, trichothecin and other organic compounds such as lauric acid. In the presence of 20% (v/v) ethanol, the viability of the mutants was 87–96%, but that of the parent was 77%. Zymolyase treatment for 3 h, decreased the viability of the parent by 44% but that of the mutants only by 11–32%. Thus the higher ethanol productivity of these mutants is related to their high ethanol tolerance and resistance to various organic compounds.

Novel devices based on a porous Pt–SnO2 metal–insulator–semiconductor field-effect transistor (MISFET) for carbon monoxide (CO) gas sensing have been proposed. The structure integrates the catalytic properties of porous Pt, a thin catalytic layer, and the spillover effect onto SnO2, a gas adsorptive oxide, with surface-sensitive MISFETs. The operation characteristics of the device for the detection of CO gas are presented as a function of CO gas concentration and operating temperature. The threshold voltage decreased rapidly with time when the device was exposed to CO gas depending on the operating temperature. It was possible to detect 54 ppm of CO gas with a response time of less than 1 min at 27°C. A model was proposed to explain the operation. The proposed sensing mechanism of the device is supported well by experimental data.

A mutant strain (KL-38) of Aspergillus oryzae was obtained by UV irradiation. Phytase activity of KL-38 in molded rice (koji rice) was about 2.7-fold of that obtained from the parent strain (BP-1). Phytase activity of KL-38 in the submerged culture was similar to that of BP-1. Two types of phytase were produced from koji culture: phytase I (Phy I) was produced during incubation of both koji and submerged cultures, and phytase II (Phy II) was obtained only from koji culture. Phy II production was increased in KL-38 compared with BP-1, whereas the production of Phy I was similar for both KL-38 and BP-1. This finding indicates that A. oryzae has at least two types of phytase isozyme.

The purpose of this article is to establish a new solid-state culture system that uses a defined medium and allows control of the chemical factors in the medium in solid-state cultivation. To achieve this purpose, we produced a solid substrate, in which the defined medium was packed in a cellulose carrier with agar, and named it "cellulose agar cube (CA-cube)". In order to obtain growth conditions similar to koji culture, we then determined the moisture content of the CA-cube. Five runs of column reactor operations were carried out at various moisture contents of the CA-cube in the range of 50-90%. A very similar mycelial morphology to that of koji culture was observed on the surface of CA-cube with moisture content lower than 63%. The glucoamylase production and the production ratio of glucoamylase to alpha-amylase (G/A ratio) were both increased exponentially with decreasing moisture content and reached 237.5 units per g dry solid and 13.59, respectively, at the moisture content of 50%, which are almost comparable to those of koji culture. In addition, the glucoamylase "glaB", which is mainly produced in koji culture, was observed in the CA-cube culture with low moisture content. These results indicate that growth conditions similar to koji culture could be attained by the column reactor culture with the CA-cube.

The physical properties and charge trapping behavior of rapid thermal N2O-oxynitrided (RTON) and rapid thermal NH3-nitrided (RTN) ultrathin SiO2 films have been investigated. The results of secondary-ion-mass spectrometry and Fourier transform infrared reflection measurements indicate that although nitrogen atoms are incorporated into the RTON and RTN films, only the RTN film shows a large number of NH bonds in the bulk SiO2. Using an analytical model, the number of oxide charge traps, the capture cross section, and the charge trap generation rate for the RTON and RTN SiO2 films were determined. Under high-field stress, the RTON SiO2 film has a much smaller number of electron and hole traps and a lower electron trap generation rate, resulting in a larger charge-to-breakdown QBD value compared to that of pure SiO2 film. In contrast, a large number of electron traps which originate from NH and SiH bonds is present in the RTN film. The differences in the charge trapping phenomena and oxide breakdown characte...

The influence of [6,6]-phenyl C61-butyric acid methyl ester (PCBM) agglomerated nanostructure on device performance of pentacene-based organic thin-film transistors (OTFTs) were reported. The presence of PCBM layers on a SiO2 gate dielectric resulted in a good electrical characteristics of pentacene-based OTFTs, including a relatively high mobility (μ = 0.95-2.2 cm2 V-1 s-1), low threshold voltages (Vth = -1.1 - -5.4 V), a high on/off current ratio (Ion/Ioff = 104), and a high value of subthreshold slope (SS = 6.5 V/decade). The surface topography studies reveal that the PCBM nanostructure could favor the reduction of grain boundaries, which resulted in a better transistor performance of pentacene-based OTFTs. The influence of PCBM on the molecular microstructure of pentacene thin films elucidates a reasonable explanation for higher performance on OTFTs.

Oxide materials have been widely used in opto-electro devices due to their wide bandgap energy, high optical transparency in the visible light region, and wide range resistance. Recently, delafossite CuMO2 (M=Al, Ga, In) have been widely studied for p-type oxide semiconductors. In this study, CuGaO2 was chosen due to its smaller lattice mismatch with ZnO compared with CuAlO2 for the possibility of p-n junction device in the future work. Zn as impurity atoms was introduced to fabricate quaternary CuZnGaO2 films to reduce lattice mismatch with ZnO. In order to study the effect of the substitute site of the Zn ion for generating donor or acceptor, 3 methods of preparation of the Cu-Zn-Ga-O sol solution were also demonstrated. In this paper, the electrical and structural properties of Zn doped on the sol-gel derived CuGaO2 films have been investigated. The diffraction angle of the CuGaO2 films are shifted to lower angle with increasing Zn%, indicating the lattice expansion which proved that the introducing Zn as impurity atoms was able to reduce lattice mismatch between CuGaO2 and ZnO. While the curve in the negative gate bias Vg proved the hole dominated transport properties. The curve in the positive gate bias can be suppressed by introducing Zn.

We introduce a charge-accepting layer on a gate dielectric to investigate the reversible threshold voltage (V th ) shifts in both p-channel and n-channel organic field-effect transistors (OFETs) using organic semiconductors of pentacene and poly-naphthalene dicarboximide [P(NDI2OD-T2)], respectively. Bottom gate with top drain-source contact structure of both devices exhibited a unipolar property of field-effect transistor behavior. Furthermore, the existence of fullerene (PCBM) and poly(3-hexylthiophene) (P3HT) films as a charge-accepting-like storage layers in p-channel and n-channel devices, respectively, resulted in a reversible V th shifts upon the application of external gate bias (V bias ). Hence, p-channel OFETs exhibited a memory window of 2.4 V and n-channel OFETs exhibited a memory window of 10.7 V for program and erase electrically upon application of gate bias.

We introduce an hole-accepting layer on a poly(methyl methacrylate) (PMMA) dielectric to investigate the reversible threshold voltage (Vth) shifts in all-polymer nchannel organic field-effect transistor (OFET) using an organic semiconductor of an poly{[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)} (P(NDI2OD-T2)). Top drain-source with a bottom-gate contact structure device exhibited a unipolar property with n-channel behavior. Furthermore, the existence of poly(3-hexylthiophene) (P3HT) films as a hole-accepting-like storage layers resulted in a reversible Vth shifts upon the application of external gate bias (Vbias). Hence, all-polymer organic transistor with the hole-accepting layer exhibited a large memory window (?Vth = 10.7 V) for write and erase electrically without major degradation in saturation mobility (μsat = 1.8~2.8×10-4 cm2 V-1 s-1).

Organic semiconductors have been the subject of interest for the past decade. Despite significant progress in the p-channel organic thin-film transistors (OTFTs), there are still problems concerning the development of n-channel OTFTs owing to the selection of n-channel organic materials, which are limited to a very small number of molecules and polymers [1], and also serious drawbacks, including poor solubility, difficulty of synthesis and unstable transistor operation under ambient atmosphere [2]. Since the first air-stable n-channel OTFTs based on naphthalenetetracarboxylic diimides was reported [3], a large number of n-channel organic materials have been based on either naphthalene diimide (NDI) — or perylene diimide (PDI)-based polymers. It is therefore clear that n-channel organic materials have an important role in the continuing development of organic-based circuits and products. In this study, we focused to elucidate the fabrication and characterization of n-channel OTFTs based on poly{[N, N'bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)} [P(NDI2D-T2)]. Moreover, we also demonstrate organic transistor memory with an n-channel P(NDI2OD-T2) OTFTs using poly(3-hexylthiophene) (P3HT) as the charge trapping layer.

We purified three xylanase isozymes (XynF1, XynF3 and XynG2) from a solid-state Aspergillus oryzae RIB128 culture using chromatography. The results of our sake-brewing experiment, in which we used exogenously supplemented enzymes, revealed that only XynG2 improved the alcohol yield and the material utilization. The alcohol yield of the XynG2 batch displayed an increase of 4.4% in comparison to the control, and the amount of sake cake decreased by 4.6%. The contribution of XynG2 was further confirmed through our brewing experiment in which we used the yeast heterogeneously expressing fungal xylanase isozymes. Interestingly XynG1, an enzyme with a XynG2-like sequence that is more vulnerable to ethanol, did not improve the sake-mash fermentation. The stability of XynG2 in ethanol was prominent, and it retained most of its original activity after we exposed it to 80% ethanol for 30min, whereas the stability of the other isozymes in ethanol, including XynG1, was much lower (20-25% ethanol). We concluded, therefore, that the improvement of material utilization achieved with XynG2 is primarily attributable to its characteristically high stability in ethanol, thereby, effectively degrading rice endosperm cell walls under high-alcohol conditions such as a sake-mash environment.

The interface trap density of states Dit of ultrathin SiO2 film has been investigated as a function of process variables. The process parameters used were oxidation temperature (1000–1200 °C), oxide thickness (4–10 nm), and annealing condition, including ambient (deuterium, argon, and in vacuum), temperature (500 and 900 °C), and time (10–120 s). Analysis of as‐grown SiO2 films showed that the Dit decreases with increasing oxidation temperature and/or oxide thickness. With annealing in argon or in vacuum at 900 °C, the Dit decreases exponentially at the initial stage, then starts to increase linearly with increasing time. Similar behavior was observed for 900 °C deuterium annealing. Deuterium annealing at 500 °C was more effective in the reduction of the Dit, whereas argon annealing at the same temperature did not affect the density at all. A possible model for annealing kinetics is proposed to explain the experimental results.

A 5.3-kbp fragment of the KHS gene was cloned from a genomic bank of Saccharomyces cerevisiae No. 115 constructed with an E. coli as the host and YEp13 as the vector. A non-killer yeast strain was transformed to a killer strain with the multi-copy vector containing the KHS gene, and the transformant could secrete 3-4 times more killer toxin into culture media than the donor, strain No. 115. The KHS toxin was purified 80-fold from the culture filtrate by gel filtration and column chromatography. The nucleotide sequence of a 2.8-kbp fragment of the KHS DNA that was enough for the expression of the killer activity was identified, and we found an open reading frame consisted of 2124 bp. Comparison of the open reading frame and N-terminal amino acid sequence of purified KHS toxin, suggested that the presumed peptide from the KHS gene might be processed between 36Gln and 37Ala before secretion.

A new method for transformation of Saccharomyces cerevisiae that allows selection was developed. As the frequency of spontaneous blasticidin S resistant mutants from diploid type yeast strain (X-2180AB) was 5.2×10−6, which was a thousandfold less than that from haploid type yeast strain (X-2180B), it was considered that the mechanism of spontaneous blasticidin S resistant mutations was related to recessive gene. Industrial yeasts, which were diploid, were transformed with blasticidin S deaminase gene from Aspergillus terreus to blasticidin S resistance. Expression of blasticidin S deaminase gene allowed selection of transformants from industrial yeasts.

Perovskite-type oxides showed the catalytic activity for NO decomposition above 773 K, which depended largely on constituent metal cations and their composition. Results obtained indicate that pero...

SiO2/Ge nanocrystal/SiO2 structures have been fabricated by deposition of Ge film on a SiO2 layer and subsequent oxidation of the structure at a temperature between 800 °C and 1000 °C. Secondary ion mass spectrometry results indicate that the Ge precipitates into the bulk SiO2 at a density of 1×1012 cm−2. Raman spectra show a sharp peak at 300 cm−1 for the nanocrystallized Ge. The nanocrystal diameter is determined to be 5 nm on average. In the metal–insulator–silicon structure, electron storage occurs in the SiO2/Ge/SiO2 potential well via electron tunneling into the oxide film. Capacitance-voltage measurements indicate that flatband voltage (VFB) shifts to 0.91 V after the electron injection. The VFB shift is attributed to the charge storing for a single electron per potential well.

In our previous study, it was determined that phytase produced by Aspergillus oryzae plays an important role in supplying phosphate to yeast in the process of making sake. During koji making, two types of phytase (Phy-I and Phy-II) are produced. The purified phytases have high thermal and pH stability, in comparison to phytase purified from a submerged culture (ACP-II). In the present study, Phy-I and Phy-II retained their activities for 45 h. The NH2-terminal sequence of Phy-1, which is eight amino acids in length, was identical to that of ACP-II, but the molecular weights of these two forms, as estimated by SDS-PAGE, were quite different from each other (Phy-I, 120 kDa; ACP-II, 58 kDa). From the NH2-terminal amino acid sequence analysis of the predominant phytase (Phy-II), a molecular weight of 116 kDa was expected to reflect a new type of phytase produced only in koji culture. The substrate specificity of Phy-II was sufficiently broad that it hydrolyzed not only phytic acid and p-nitro phenyl phosphate, but also glucose 6-phosphate and glycerol 1-phosphate. In the process of making koji, Phy-I was produced at an early stage, followed by Phy-II; with both phytases being thought to function to hydrolyze phytic acid cooperatively.

Flash-type EEPROMs with rapid thermal oxide (RTO) and rapid thermal oxynitrided oxide (RTONO) films are fabricated. The oxide trap density in the program and erase (P/E) cycles is determined by the shifts in I-V curves for the source-gate and drain-gate edges, respectively. The RTONO flash cell shows a drastically reduced trap density of less than 3*10/sup 12//cm/sup 2/ after 10/sup 4/ P/E cycles. This value is one order smaller than that of the RTO flash cell. This smaller oxide trap density originates in the stable Si-N bond formation near the SiO/sub 2/-Si interface, and results in lower threshold voltage shifts.

Hydrogen annealing effects on SiO2/Si(100) interface traps and bulk oxide traps have been investigated through deuterium (D2) anneal of ultra-thin SiO2 films. The interface traps are annihilated by low-temperature D2 anneal, whereas high-temperature anneal allows for the increase of interface traps. The increase of anomalous leakage current after D2 anneal is also observed. It is considered that deuterium-related electron traps are generated, thereby trap-assisted current increases.

An investigation of threshold voltage shifts in organic thin-film transistors (OTFTs) based on poly[N,N '-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene) [P(NDI2OD-T2)] with additional poly(3-hexylthiophene) (P3HT) films on a poly(methyl methacrylate) (PMMA) organic dielectric layer is reported. With a top source-drain contact structure, the device exhibited a unipolar property with n-channel characteristics similar to those of the P(NDI2OD-T2)-only device. Furthermore, the existence of P3HT films as hole acceptor-like storage layers resulted in reversible V th shift upon the application of external gate bias (V bias) for a certain bias time (T bias). Hence, the P(NDI2OD-T2)/P3HT-OTFTs exhibited a large memory window (ΔV th = 10.7 V) for write and erase electrically without major degradation in saturation mobility [µsat = (1.8–2.8) ×10-4 cm2 V-1 s-1]. These results clearly indicate the utility of the naphthalene–bis(dicarboximide) (NDI)-based polymer–hole acceptor layer in the development of n-channel organic transistor memories.

An investigation of threshold voltage shifts in organic thin-film transistors (TFTs) based on pentacene with an additional soluble fullerene derivatives of [6,6]-phenyl C61-butyric acid methyl ester (PCBM) on gate dielectric. With an additional soluble fullerene layer, the threshold voltage (V th) is optimized from -3.9 to -1.1 V without affect the mode operation of the devices, while retaining the carrier mobility (0.02–0.03 cm2 V-1 s-1) and on/off current ratio (∼104). Furthermore, the existence of PCBM agglomerates as electron acceptor-like traps resulted in a shift of V th in the positive and reversible directions depending on the magnitude of gate bias (V bias) as well as duration of time bias (T bias). The device operation changed into normally-on (depletion–accumulation) mode upon positive V bias as the duration of T bias was increased, which attributes to the formation of a conductive layer at the pentacene–fullerene interface. Moreover, the recovery of V th was further enhanced by a high negative V bias for a short duration. In addition, the mobility was minimally affected by both V bias conditions.

Trichothecin-resistant mutants were isolated from sake yeast. These mutants were subjected to sake brewing, and showed a higher ethanol productivity than did the parents. They showed multidrug resistance, and resistance to organic compounds. We considered that the higher ethanol productivity of the mutants was related to their resistance to organic compounds and to their ethanol tolerance.

Ultrathin silicon oxynitride films are prepared by ozone and thermal oxidation of Si(001) followed by rapid thermal nitridation. The nitrogen depth profiles in these films are measured by high-resolution Rutherford backscattering spectroscopy. The observed nitrogen profiles are essentially similar, having a peak at the SiO2/Si interface, although the interface strain in the ozone oxide is known to be much smaller than that of the thermal oxide. This indicates that the interface strain relaxation due to the nitrogen incorporation is not responsible for the nitrogen accumulation at the interface.

A novel device based on a porous Pt–WO3 metal-insulator-semiconductor field-effect transistor (MISFET) for carbon monoxide (CO) gas sensing has been fabricated. The structure integrates the catalytic properties of porous Pt as a thin catalytic layer, and the spillover effect onto WO3 film as a gas adsorptive oxide layer, with surface-sensitive MISFET. The operation characteristics of the device for the detection of CO gas are presented as a function of CO gas concentration. The drain current increased rapidly with time depending on the CO gas concentration. It was possible to detect 54 ppm of CO gas with a response time of less than 1 min at 75°C. A model was proposed to explain the operation. The sensing mechanism of the device is supported well by experimental data.

Novel gas-sensing devices based on a porous Pt-SnO2 metal-oxide-semiconductor field-effect transistor (MOSFET) for carbon monoxide (CO) gas sensing have been fabricated. The structure integrates the catalytic properties of porous Pt, a thin catalytic layer, and the spillover effect onto SnO2, a gas adsorptive oxide, with surface-sensitive MOSFETs. The operation characteristics of the device for the detection of CO are presented as a function of CO gas concentration and operating temperature. The threshold voltage decreased rapidly with time when the device was exposed to CO gas. It was possible to detect 54 ppm of CO gas with a response time of less than 1 min at an operating temperature of 27°C. A model was proposed to explain the operation. The proposed sensing mechanism of the device is supported well by experimental data.

A larger charge-to-breakdown value and much less threshold-voltage narrowing in the endurance properties of flash electrically erasable and programmable ROMs were achieved by incorporating a greater amount of nitrogen ( ∼1021 atoms/cm3) into the bulk of thin oxide films, as well as near the oxide/Si interface. The charge to breakdown value of thin oxide films formed under an optimized heavy oxynitride condition (dry oxidation at 1100° C; NH3 annealing at 1000° C for 30 s; N2O annealing at 1100° C for 30 s) was four times as large as that of a conventional dry oxide film. These results were attributed to the suppression of stress-induced charge traps and the interface state, due to the introduction of nitrogen atoms in the oxide bulk, as well as at the oxide/Si interface.