Development of hydrophobic platinum catalyst for oxidation of tritium in JAEA

AbstractTo design a recombiner packed with hydrophobic catalyst for passive tritium oxidation, the development of manufacturing technology for hydrophobic platinum catalyst and the following analysis on reaction rate are essential. This presentation deals with the reaction rate for tritium oxidation over a hydrophobic platinum catalyst at temperature between room temperature and 473K. Two kinds of hydrophobic platinum catalysts; supported with styrene-divinylbenzene and with silica were used for this test. The results indicate that 1) the particle size of platinum affects the reaction rate, 2) the order of reaction is 0.5 of hydrogen concentration at room temperature in case of a hydrogen content below 100ppm. The rate-determining step approximation method is applied for the discussion on the reaction mechanism of tritium oxidation over platinum catalyst

Expression of Bitter Taste Receptors in the Intestinal Cells of Non-Human Primates

(1) Background: Recent studies have investigated the expression of taste-related genes in the organs of various animals, including humans; however, data for additional taxa are needed to facilitate comparative analyses within and among species. (2) Methods: We investigated the expression of taste-related genes in the intestines of rhesus macaques, the non-human primates most commonly used in experimental models. (3) Results: Based on RNAseq and qRT-PCR, genes encoding bitter taste receptors and the G-protein gustducin were expressed in the gut of rhesus macaques. RNAscope analysis showed that one of the bitter receptors, TAS2R38, was expressed in some cells in the small intestine, and immunohistochemical analysis revealed the presence of T2R38-positive cells in the villi of the intestines. (4) Conclusions: These results suggest that bitter receptors are expressed in the gut of rhesus macaques, supporting the use of macaques as a model for studies of human taste, including gut analyses

Development of integrated analysis software of observation data in the upper atmosphere

Workshop at NARL, Gadanki, India27-29 March 2011 - Recent Advances in Observational Studies of the Tropical Atmosphere and Ionosphere

Temperature-dependent device properties of gamma-CuI and beta-Ga2O3 heterojunctions

Temperature-dependent studies of Ga2O3-based heterojunction devices are important in understanding its carrier transport mechanism, junction barrier potential, and stability at higher temperatures. In this study, we investigated the temperature-dependent device characteristics of the p-type gamma-copper iodide (gamma-CuI)/n-type beta-gallium oxide (beta-Ga2O3) heterojunctions, thereby revealing their interface properties. The fabricated gamma-CuI/beta-Ga2O3 heterojunction showed excellent diode characteristics with a high rectification ratio and low reverse saturation current at 298 K in the presence of a large barrier height (0.632 eV). The temperature-dependent device characteristics were studied in the temperature range 273-473 K to investigate the heterojunction interface. With an increase in temperature, a gradual decrease in the ideality factor and an increase in the barrier height were observed, indicating barrier inhomogeneity at the heterojunction interface. Furthermore, the current-voltage measurement showed electrical hysteresis for the reverse saturation current, although it was not observed for the forward bias current. The presence of electrical hysteresis for the reverse saturation current and of the barrier inhomogeneity in the temperature-dependent characteristics indicates the presence of some level of interface states for the gamma-CuI/beta-Ga2O3 heterojunction device. Thus, our study showed that the electrical hysteresis can be correlated with temperature-dependent electrical characteristics of the beta-Ga2O3-based heterojunction device, which signifies the presence of surface defects and interface states

Characteristics of Vertical Ga2O3 Schottky Junctions with the Interfacial Hexagonal Boron Nitride Film

We present the device properties of a nickel (Ni)- gallium oxide (Ga2O3) Schottky junction with an interfacial hexagonal boron nitride (hBN) layer. A vertical Schottky junction with the configuration Ni/hBN/Ga2O3/In was created using a chemical vapor-deposited hBN film on a Ga(2)O(3 )substrate. The current-voltage characteristics of the Schottky junction were investigated with and without the hBN interfacial layer. We observed that the turn-on voltage for the forward current of the Schottky junction was significantly enhanced with the hBN interfacial film. Furthermore, the Schottky junction was analyzed under the illumination of deep ultraviolet light (254 nm), obtaining a photoresponsivity of 95.11 mA/W under an applied bias voltage (-7.2 V). The hBN interfacial layer for the Ga2O3-based Schottky junction can serve as a barrier layer to control the turn-on voltage and optimize the device properties for deep-UV photosensor applications. Furthermore, the demonstrated vertical heterojunction with an hBN layer has the potential to be significant for temperature management at the junction interface to develop reliable Ga2O3-based Schottky junction devices

Quantitative Assessment of Gait Bradykinesia in Parkinson’s Disease Using a Portable Gait Rhythmogram

To quantify gait bradykinesia during daily activity in patients with Parkinson's disease (PD), we measured movement-induced accelerations over more than 24h in 50 patients with PD and 17 age-matched normal controls, using a new device, the portable gait rhythmogram. Acceleration values induced by various movements, averaged each 10 min, exhibited a gamma distribution. The mean value of the distribution curve was used as an index of the "amount of overall movement per 24h". Characteristic changes were observed in both the gait cycle and gait acceleration. During hypokinesia, the gait cycle became either faster or slower. A number of patients with marked akinesia/bradykinesia showed a reduced and narrow range of gait acceleration, i.e., a range of floor reaction forces. The results suggest that assessment of the combination of changes in gait cycle and gait acceleration can quantitatively define the severity of gait bradykinesia

A Proposal for New Algorithm that Defines Gait-Induced Acceleration and Gait Cycle in Daily Parkinsonian Gait Disorders

We developed a new device, the portable gait rhythmogram (PGR), to record up to 70 hrs of movement-induced accelerations. Acceleration values induced by various movements, averaged every 10 min, showed gamma distribution, and the mean value of this distribution was used as an index of the amount of overall movements. Furthermore, the PGR algorithm can specify gait-induced accelerations using the pattern-matching method. Analysis of the relationship between gait-induced accelerations and gait cycle duration makes it possible to quantify Parkinson’s disease (PD)-specific pathophysiological mechanisms underlying gait disorders. Patients with PD showed the following disease-specific patterns: (1) reduced amount of overall movements and (2) low amplitude of gait-induced accelerations in the early stages of the disease, which was compensated by fast stepping. Loss of compensation was associated with slow stepping gait, (3) narrow range of gait-induced acceleration amplitude and gait cycle duration, suggesting monotony, and (4) evident motor fluctuations during the day by tracing changes in the above two parameters. Prominent motor fluctuation was associated with frequent switching between slow stepping mode and active mode. These findings suggest that monitoring various movement- and gait-induced accelerations allows the detection of specific changes in PD. We conclude that continuous long-term monitoring of these parameters can provide accurate quantitative assessment of parkinsonian clinical motor signs

Evolution of the primate glutamate taste sensor from a nucleotide sensor

霊長類におけるグルタミン酸の旨味の起源 --体の大きな霊長類は旨味感覚で葉の苦さを克服--. 京都大学プレスリリース. 2021-08-30.Taste perception plays an essential role in food selection. Umami (savory) tastes are sensed by a taste receptor complex, T1R1/T1R3, that detects proteinogenic amino acids. High sensitivity to l-glutamate (l-Glu) is a characteristic of human T1R1/T1R3, but the T1R1/T1R3 of other vertebrates does not consistently show this l-Glu response. Here, we demonstrate that the l-Glu sensitivity of T1R1/T1R3 is a derived state that has evolved repeatedly in large primates that rely on leaves as protein sources, after their divergence from insectivorous ancestors. Receptor expression experiments show that common amino acid substitutions at ligand binding sites that render T1R1/T1R3 sensitive to l-Glu occur independently at least three times in primate evolution. Meanwhile T1R1/T1R3 senses 5′-ribonucleotides as opposed to l-Glu in several mammalian species, including insectivorous primates. Our chemical analysis reveal that l-Glu is one of the major free amino acids in primate diets and that insects, but not leaves, contain large amounts of free 5′-ribonucleotides. Altering the ligand-binding preference of T1R1/T1R3 from 5′-ribonucleotides to l-Glu might promote leaf consumption, overcoming bitter and aversive tastes. Altogether, our results provide insight into the foraging ecology of a diverse mammalian radiation and help reveal how evolution of sensory genes facilitates invasion of new ecological niches

A novel role of serum cytochrome c as a tumor marker in patients with operable cancer.

PURPOSE: This study aimed to evaluate serum cytochrome c (cyto-c) levels as a novel role of tumor marker in patients with operable malignant tumors. METHODS: Serum cyto-c levels and lactate dehydrogenase (LD) activity were measured in a total of 257 cases (232 malignant and 25 benign). To identify the relationship between serum cyto-c and current tumor markers, six variables, such as gender, age, invasion, lymph node metastasis, distant metastasis, and LD, were analyzed by uni- and multivariate regression analysis methods. The test performance of serum cyto-c for the prediction of malignant behavior was evaluated by receiver operating characteristic (ROC) curves. RESULTS: The serum cyto-c level was significantly higher in patients with malignant tumors than patients with benign tumors (20.6 vs. 15.5 ng/mL; P = 0.017, Mann-Whitney U test). No difference in the levels among subtypes of cancer was found, indicating that the change in serum cyto-c levels reflect cancer individually and not specific subtypes of cancer. The survival in patients with serum cyto-c levels over 40 ng/mL was poor (Kaplan-Meier test, P < 0.0001, Hazard ratio 16.76, 95% confidential interval 4.45-63.04). Multiple linear regression analyses disclosed the close association of serum cyto-c levels with invasion (P = 0.0004), metastasis (P = 0.0262) except for regional lymph node metastasis, and activity of serum LD (P < 0.0001), all of which are well known to represent malignant behavior. Conversely, the measurement of serum cyto-c was verified to have excellent diagnostic accuracy of 0.802 and 0.781 for the detection of invasion and metastasis (the area under curves of the constructed ROCs). CONCLUSION: Serum cyto-c is a potent tumor marker as a predictor for malignant potential in cancers