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Background: Colon capsule endoscopy (CCE) is useful as an alternative examination for patients in whom colonoscopy is difficult. The Japanese Association for Capsule Endoscopy has published a recommended regimen for CCE using castor oil, which is becoming a standard examination method for CCE in Japan. However, castor oil has an unpleasant flavor. Therefore, patient acceptance is not good. Objectives: The aims were to develop a castor oil-filled capsule and evaluate its feasibility and patient acceptance in a retrospective, comparative study. Method: A dissolution study of pig-derived gelatin capsules filled with castor oil was performed using artificial gastric juice. The CCE excretion rates within battery lifetime, CCE examination times, endoscopic colonic cleansing levels, and patient acceptability between CCE boosters with a castor oil-filled capsule and without castor oil were retrospectively compared using medical information, clinical data, and endoscopic findings at Takada Chuo Hospital from September 2016 to August 2019. Results: The castor oil-filled capsules were completely disintegrated at approximately 1–3 min in artificial gastric juice. Bowel preparation with oil-filled capsules and without castor oil was performed in 27 and 24 patients, respectively. CCE excretion rates within battery life were 100% and 91.7% (p = 0.217), small bowel transit times were 115 min and 143 min (p = 0.046), colon transit times were 168 min and 148 min (p = 0.733), and adequate colonic cleansing rates were 85.2% and 86.3% (p = 1.000) in patients using bowel preparation with and without oil-filled capsules, respectively. Regarding acceptance, the taste was not problematic in 85.2%, and tolerability for the next CCE was 96.3%. Conclusions: CCE using a castor oil-filled capsule method achieved high examination performance and sufficient patient tolerability.

Hematin is a state in which hemoglobin, as petechiae, is discolored to a brown coffee color by gastric hydrochloric acid. Given the nature of hematin, a close relationship between hematin and acidity has been suggested, but has not been confirmed. We investigated the clinical significance of endoscopic finding of hematin with respect to gastric acidity.A total of 501 patients were assessed for both hematin and fasting gastric juice pH by endoscopy. Endpoints were as follows: 1) the relationship between the presence of hematin and the fasting gastric juice pH; and 2) the diagnostic performance of endoscopic hematin. In addition, we performed a supplementaryThe prevalence of hematin was 31.1% (142/206), 4.6% (5/109) and 45.2% (84/186) in theEndoscopic finding of hematin represent strong gastric acidity.

The objective of this study is to formulate a methodology to predict a fission gas release ratio of MIMAS MOX. An irradiated MIMAS MOX fuel with plutonium rich agglomerates was subjected to elemental analyses by electron probe micro analysis and secondary ion mass spectrometry in order to investigate xenon distribution. The results of the elemental analyses showed that the plutonium rich agglomerates at the periphery of the fuel pellet sample retained a high concentration of xenon as gas bubbles. Then, the results were used as reference data for modification of models in a fuel rod analysis code, FEMAXI-7. Using the modified FEMAXI-7, we applied an approach to prediction of fission gas release ratio of MOX fuel with plutonium rich agglomerates. In the approach, two separated analyses using FEMAXI-7 were performed for the plutonium rich agglomerates and the matrix. Fission gas release ratios obtained from the two analyses were processed through weighted-average with burnup ratios of the plutonium r...

Thermal property is important because it controls fuel behavior under irradiation. The thermal property change at high burnup of more than 70 GWd/t is examined. Two kinds of MOX fuel rods, which were fabricated by MIMAS and SBR methods, and one referenced UO 2 fuel rod were used in the experiment. These rods were taken from the pre-irradiated rods (IFA 609/626, of which irradiation test were carried out by Japanese PWR group) and re-fabricated and re-irradiated in HBWR as IFA 702 by JNES. The specification of fuel corresponds to that of 17 × 17 PWR type fuel and the axially averaged linear heat rates (LHR) of MOX rods are 25 kW/m (BOL of IFA 702) and 20 kW/m (EOL of IFA 702). The axial peak burnups achieved are about 74 GWd/t for both of MOX and UO 2 . Centerline temperature and plenum gas pressure were measured in situ during irradiation. The measured centerline temperature is plotted against LHR at the position where thermocouples are fixed. The slopes of MOX are corresponded to each other, but that of UO 2 is higher than those of MOX. This implies that the thermal conductivity of MOX is higher than that of UO 2 at high burnup under the condition that the pellet–cladding gap is closed during irradiation. Gap closure is confirmed by the metallography of the postirradiation examinations. It is understood that thermal conductivity of MOX is lower than that of UO 2 before irradiation since phonon scattering with plutonium in MOX becomes remarkable. A phonon scattering with plutonium decreases in MOX when burnup proceeds. Thus, thermal conductivity of MOX becomes close to that of UO 2 . A reverse phenomenon is observed at high burnup region. The phonon scattering with fission products such as Nd and Zr causes a degradation of thermal conductivity of burnt fuel. It might be speculated that this scattering effect causes the phenomenon and the mechanism is discussed here.

Detection of GZK (Greisen, Zatsepin and Kuzmin) neutrinos that have an energy larger than 1×1016 eV are expected to explore ultra-high-energy (UHE) interactions between UHE protons (>4×1019 eV) and cosmic-microwave background in the cosmological distances. A study of the radar method was carried out using a 2 MeV electron beam to irradiate rock salt powder filled in a 435 MHz waveguide. Reflection of radio wave from the irradiated rock-salt powder was observed inside the waveguide. The reflection mechanism was elucidated and the reflection power ratio was compared with a Fresnel equation.

Penicillolysin is a member of the clan MX and the family of M35 proteases. The enzyme is a thermolabile Zn(2+)- protease from Penicillium citrinum with a unique substrate profile. We expressed recombinant penicillolysin in Aspergillus oryzae and generated several site-directed mutants, R33E/E60R, A167E and T81P, with the intention of exploring thermal stabilization of this protein. We based our choice of mutations on the structures of homologous thermally stable enzymes, deuterolysin (EC 3.4.24.39) from A.oryzae and a peptidyl-Lys metallopeptidase (GfMEP) from the edible mushroom Grifora frondsa. The resulting mutant proteins exhibited comparable catalytic efficiency to the wild-type enzyme and some showed a higher tolerance to temperature.

An experimental study of precision cutting of molding dies using single crystal diamond cutting tools for large Fresnel screens(size : T3×921×714mm3, Fresnel angle : 0.004-55.0°), for improving the optical characteristics of the screens is described. The conclusions are as follows : (1)A burr is generated at the shoulder of the grooves during cutting, which causes compressed chip material to accumulate and laterally compress both sidewalls of the grooves ; (2)the burr generation is suppressed by increase of the rake angle of the diamond cutters, decrease of the down feed rate, and reduction of stock removal ; (3)generation of a color corn on the Fresnel screen is caused by light escaping through non-lens surfaces ; this is avoided by making the non-lens surfaces semi-transparent where the surface roughness is around 1μm Rmax. Using the above-mentioned information to improve the cutting process, desirable optical characteristics were achieved for Fresnel screens used in projection TVs.

An experimental study of precision cutting of molding dies using single crystal diamond cutting tools for large Fresnel screens (size: T3×921×714 mm, Fresnel angle: 0.004-55.0), for improving the optical characteristics of the screens is described. The conclusions are as follows: (1) A burr is generated at the shoulder of the grooves during cutting, which causes compressed chip material to accumulate and laterally compress both sidewalls of the grooves; (2) The burr generation is suppressed by increase of the rake angle of the diamond cutters, decrease of the down feed rate, and reduction of stock removal; (3) Generation of a color corn on the Fresnel screen is caused by light escaping through non-lens surfaces; this is avoided by making the non-lens surfaces semi-transparent where the surface roughness is around 1μm Rmax Through use of the above-mentioned information to improve the cutting process, desirable optical characteristics were achieved for Fresnel screens used in projection TVs.

An ultra-high-energy neutrino (UHEν) gives temperature rise along the hadronic and electromagnetic shower when it enters into rock salt or ice. Permittivities of them arise with respect the temperatures at ionization processes of the UHEν shower. It is expected by Fresnel's formula that radio wave reflects at the irregularity of the permittivity in the medium. We had found the radio wave reflection effect in rock salt. The reflection effect and long attenuation length of radio wave in rock salt and ice would yield a new UHEν detection method. An experiment for ice was performed to study the reflection effect. A coaxial tube was filled with rock salt powder or ice. Open end of the coaxial tube was irradiated by a 2 MeV electron beam. Radio wave of 435 MHz was introduced to the coaxial tube. We measured the reflection wave from the open end. We found the radio wave reflection effect due to electron beam irradiation in ice as well as in rock salt.

We had found radio-wave-reflection effect in rock salt for detection of an ultra-high energy neutrino (UHEν) which is generated in GZK processes in the universe. When an UHEν interacts with rock salt or ice as a detection medium, the energy converts to a thermal energy. Consequently, a temperature gives rise along an UHEν shower at the interaction location. The permittivity arises with respect to the temperature at ionization processes of the UHEν shower which is composed of hadronic and electromagnetic multiplication processes. The irregularity of the refractive index in the medium for radio wave rises to a reflection. The reflection effect with a long attenuation length of radio wave in rock salt and ice would yield a new method to detect UHEν. They could be used for detection media in which the UHEν interacts with. We could find a huge amount of rock salt or ice over 50 Gt in a natural rock salt formation or Antarctic ice sheet. Radio wave transmitted into the medium generated by a radar system could be reflected by the irregularity of the refractive index at the shower. Receiving the reflected radio wave yields information about the UHEν.

The heat capacity of gold has been measured by laserflash calorimetry in the temperature range 80–1000 K. The results are compared with available low- and high-temperature heat capacities, and revised thermodynamic values of gold are given.