Observation of large diamagnetism in La-Sr-Nb-O films up to room temperature

Large diamagnetic transitions along with sharp resistive transitions were observed in the La-Sr-Nb-O system near room temperature (290 K). The amplitude of the diamagnetism reaches 35% of that of a pure Nb sheet. In addition, a behavior similar to weak magnetic spin ordering was observed for some samples at a temperature of about 290 K, over a temperature range of 30 K. The diamagnetism reappears above this temperature and continues up toT 320 K. It is not clear what composition ratio of La-Sr-Nb-O is responsible for this large diamagnetism and the high critical temperature. The yield probability of these samples is around 50%. The characteristics of the samples having not passed through many thermal cycles remain stable for about 1 month.     

A new life extension method for high cycle fatigue using micro-martensitic transformation in an austenitic stainless steel

Most of the conventional strengthening methods for metals and alloys such as work hardening, precipitation hardening, cause a decrease in ductility and are not very effective for cyclic loading. In this study, a new strengthening method, which is effective for high cycle fatigue, has been developed. The intersections of dislocations in a stainless steel are freezed by very fine martensite particles, which are supposed to suppress dislocation motion at low stress amplitudes. Fatigue life in a high cycle regime increased >60 times, and no decrease in ductility was observed in tensile tests, as compared to a work-hardened stainless steel.     

A Dietary Oxysterol, 7-Ketocholesterol,Exacerbates Imiquimod-Induced Psoriasis-like Dermatitis in Steatohepatitic Mice

Patients with psoriasis are at a higher risk of developing nonalcoholic fatty liver disease. We previously identified an oxidized derivative of cholesterol, 7-ketocholesterol (7KC), in diet-induced steatohepatitic mice. Here, we investigated whether 7KC exacerbates psoriasis-like dermatitis by accelerating steatohepatitis in mice. A high-fat/high-cholesterol/high-sucrose/bile salt diet (nonalcoholic steatohepatitis (NASH) diet) with or without 0.0125% 7KC was fed to C57BL/6 mice (7KC or control group) for three weeks to induce steatohepatitis. A 5% imiquimod cream was then applied to the ears and dorsal skin for four days to induce psoriasis-like dermatitis. Hepatic lipid accumulation and inflammatory cell infiltration were exacerbated in the 7KC group compared with the control group after three weeks. Serum tumor necrosis factor-α (TNF-α) levels were also elevated in the 7KC group (108.5 ± 9.8 vs. 83.1 ± 13.1 pg/mL, p < 0.005). Imiquimod cream increased the psoriasis area severity index (PASI) score in mice in the 7KC group (9.14 ± 0.75 vs. 5.17 ± 1.17, p < 0.0001). Additionally, Tnfa, Il23a, Il17a, and Il22 mRNA levels in the dorsal lesion were significantly upregulated. Finally, Th17 cell differentiation and the TNF signaling pathway were enhanced in the dorsal lesions and liver of mice in the 7KC group. These data suggest that steatohepatitis and psoriasis are linked by a potent, diet-related factor.     

Development of rapid hygrothermal pasteurization using saturated water vapor

We developed a novel rapid hygrothermal pasteurization (RHP) method using saturated water vapor with a dew point of 100 °C. In the present study, the effects of RHP on microbiological quality and quality attributes such as color changes, firmness and ascorbic acid content on many fresh-cut fruits and vegetables (cabbage, cucumber, carrot, cherry tomato, bell pepper, strawberry, pineapple and melon) were investigated. The RHP was performed within a second by free-falling samples through a cylindrical processing chamber filled with steam. The RHP resulted in a 0.7–2.0 log order reduction in the numbers of naturally inoculated mesophilic bacteria. Furthermore, the RHP induced no significant changes in color and firmness of samples, except on the leafy vegetable, cabbage. Ascorbic acid was also retained approximately 80% and above. These results indicate that the RHP is a clean and effective method for decontaminating mesophilic bacteria on fresh fruits and vegetables with minimal changes in quality.Industrial relevanceIn fresh-cut industry, an effective and risk-free decontamination technology is required for use in place of a conventional method, washing by chlorine that can produce carcinogenic chlorinated by-products. In this study, the rapid hygrothermal pasteurization (RHP) method using saturated water vapor was invented and their ability for applying minimal processing was evaluated. The results showed that RHP, without using chemicals, can reduce microorganism load and preserve quality attributes in many kinds of fresh-cut fruits and vegetables. Therefore, RHP could be used as a novel method, which can be generally applicable to fresh-cut fruits and vegetables in the food industry.     

Enhancement of peroxynitrite-evoked acetylcholine release by hydroxyl radical scavengers from mouse cerebral cortical neurons

We investigated the effects of hydroxyl radical scavengers on peroxynitrite (OONO-)-evoked acetylcholine (ACh) release from mouse cerebral cortical neurons. N,N'-dimethylthiourea, a hydroxyl radical scavenger, dose-dependently increased OONO(-)-evoked ACh release. Other hydroxyl radical scavengers such as uric acid and mannitol, also enhanced OONO(-)-evoked ACh release, although these enhancing effects were not found in the absence of OONO-. In addition, OONO(-)-induced [45Ca2+]influx was significantly facilitated by the scavengers, whereas no effects of the scavengers on [45Ca2+]influx was observed in the absence of OONO-. These results indicate that hydroxyl radical scavengers enhance OONO(-)-evoked ACh release via the facilitation of OONO(-)-induced [45Ca2+]influx.     

Preparation of nickel-tungstate catalysts by a novel impregnation method

Nickel-tungstate/γ-alumina (NiW) catalysts were prepared by an incipient wetness impregnation method using citric acid as a complexing agent. Citric acid has been used by our research group in preparing cobalt-molybdate and nickel -molybdate catalysts. The extended X-ray absorption fine structure (EXAFS) data of the impregnating solutions indicated that citric acid contributes to the formation of polytungstate anions that are smaller than the dodecatungstate ions formed when conventional ammoniacal solutions are used. Sulfided NiW catalysts prepared by using citric acid showed higher hydrogenation activity and hydrogenation selectivity than NiW catalysts prepared using the conventional ammoniacal solutions.     

Investigation of localized deformation in partially saturated sand under triaxial compression using microfocus X-ray CT with digital image correlation

In this paper, localized deformation in partially saturated sand was investigated quantitatively using microfocus X-ray computed tomography (CT) and an image analysis of the CT images. Triaxial compression tests on a partially saturated dense Toyoura sand specimen were carried out under a low confining pressure and under drained conditions for both air and water. The development of localized deformation was observed macroscopically using microfocus X-ray CT, and the displacement field over the entire specimen was quantified by an image analysis of the CT images with the digital image correlation (DIC) technique. The progressive development of shear bands is discussed with reference to these images. In addition, the region of localization was observed microscopically by partial CT scanning on a micron scale with high spatial resolution. Changes in the particulate structures are also discussed herein. The DIC image analysis of the partial CT images provided a microscopic displacement field and indicated that very fine localized shear deformation developed before the shear bands had become visible in the macroscopic investigation.     

A Coupled MPM-FDM Analysis Method for Multi-Phase Elasto-Plastic Soils

The Material Point Method (MPM), as proposed by Sulsky et al. (1994), has been developed to simulate large deformations and failure evolution involving different material phases in a single computational domain. A continuum body is divided into a finite number of subregions represented by Lagrangian material points, while the governing equations are formulated and solved with the Eulerian grid. Since this grid can be chosen arbitrarily, mesh tangling does not appear in the MPM. To design a simple but robust spatial discretization procedure, the MPM is coupled with the finite difference method (FDM) in the present study for simulating fully and partially saturated elasto-plastic soil responses based on the simplified three-phase method. Governing equations for the soil skeleton and the pore fluid are discretized by the MPM and FDM, respectively. Soil-water coupled analyses for fully saturated soils and seepage-deformation coupled analyses for unsaturated soils are performed, and the potential of the proposed method is demonstrated via numerical examples.     

950 keV, 3.95 MeV and 6 MeV X-band linacs for nondestructive evaluation and medicine

We are developing compact X-band linac X-ray sources for nondestructive evaluation and medicine. First, we develop a portable X-ray system by a 950 keV 9.4 GHz X-band linac to realize on-site inspection. We use a low power (250 kW) magnetron as an RF source for compactness of the whole system. Since the RF power source is quite small and the stored energy in the structure is also small, we faced the problem of beam loading and current/RF-power oscillation. We are analyzing the problem by the circuit model. We plan to use this system for erosion inspection of metal pipes of petrochemical complex. By adopting a side-coupling cavity design to avoid the oscillation, we have developed 6 MeV X-band (9.3 GHz) linac for pinpoint dynamic tracking cancer therapy. Furthermore, we are manufacturing 3.95 MeV X-band (9.3 GHz) linac X-ray source with flexible waveguides for on-site bridge inspection. Updated results and situations are presented.     

Alterations in cholesterol sulfate and its biosynthetic enzyme during multistage carcinogenesis in mouse skin

A novel series of nonpeptide angiotensin II antagonists containing the acrylamide group at the 4-position of the imidazole ring was synthesized and their antagonistic activity was examined by functional assay in rabbit aorta. The acrylamide group was selected as a large lipophilic surrogate for the chloro group of EXP3174. A structure-activity relationship study of the acrylamide moiety has shown that substitution at the 4-position with the N-methyl-3,3-dimethylacrylamide group resulted in the optimal compound, 2-butyl-4-[(3,3-dimethylacryloyl)methyl-amino]-1-[[2'-(1H-tetra zol-5- yl)biphenyl-4-yl]methyl]-1H-imidazole-5-carboxylic acid (1), which was superior to EXP3174 in vitro. Since 1 showed only poor activity against angiotensin II-induced pressor response in rats after oral administration, the carboxylic acid function of 1 was converted into prodrug esters (13). Among these, the 1-[(ethoxycarbonyl)oxy]ethyl ester (13a) showed the most potent and longest-lasting activity when given orally to rats. When administered orally to conscious furosemide-treated dogs, 13a showed an approximately 3-fold increased hypotensive activity in comparison with DuP 753. These data suggest that 13a may be an useful agent for the treatment of angiotensin II-dependent diseases, such as hypertension.