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This purpose of study is to establish the material database of neutron multiplier for the JA DEMO design. In the previous study, we reported the effects of sintering conditions as temperature and pressure on hardness and sintered density mainly in the sintering temperature from 1050 °C to 1200 °C. In this study, the microstructure observation and compressive tests were carried out. As results of microstructure observations, the pores were almost disappeared, and the grain size increased with increase in sintering temperature. Compression tests were carried out from room temperature (R.T.) to 1000 °C with the samples sintered at 1200 °C. The compressive strength at R.T. was approximately 1.69 GPa. With the increase in testing temperature, there was a tendency for the strength to decrease from 800 °C to 1000 °C. In addition, the load-compressibility indicated that the yield point appears at 850 °C.

We examined the effects of endurance training with chronic pre-exercise concentrated Kurozu (black vinegar) supplementation on mitochondrial enzyme activity and energy metabolism in Institute of Cancer Research (ICR) mice. Mice were divided into a control group, an endurance training group, and an endurance training + concentrated Kurozu supplementation group. Mice were orally supplemented with water or concentrated Kurozu solution (500 mg/kg body weight/day) for 3 weeks. The mice in the training group were subjected to exercise on a treadmill (20–25 m/min × 30 min, five times/week) starting 30 min after the supplementation. The maximal activity of citrate synthase in the plantaris muscle in the endurance training + concentrated Kurozu supplementation group was significantly higher than that in the control group (p < 0.01). The maximal activity of β-hydroxyacyl coenzyme dehydrogenase (β-HAD) in the soleus muscle in the endurance training + concentrated Kurozu supplementation group was significantly higher than that in the other two groups (p < 0.05 for both). In the final week, significant negative correlation between blood lactate concentration after exercise and soleus β-HAD activity was observed. These findings suggest that endurance training with concentrated Kurozu supplementation increases mitochondrial enzyme activity and might enhance lipid metabolism during exercise.

BackgroundThe mortality rate of acute coronary syndrome (ACS) remains high. Therefore, patients with ACS should undergo early risk stratification, for which various risk calculation tools are available. However, it remains uncertain whether the predictive performance varies over time between risk calculation tools for different target periods. This study aimed to compare the predictive performance of risk calculation tools in estimating short- and long-term mortality risks in patients with ACS, while considering different observation periods using time-dependent receiver operating characteristic (ROC) analysis.MethodsThis study included 404 consecutive patients with ACS who underwent coronary angiography at our hospital from March 2017 to January 2021. The ACTION and GRACE scores for short-term risk stratification purposes and CRUSADE scores for long-term risk stratification purposes were calculated for all participants. The participants were followed up for 36 months to assess mortality. Using time-dependent ROC analysis, we evaluated the area under the curve (AUC) of the ACTION, CRUSADE, and GRACE scores at 1, 6, 12, 24, and 36 months.ResultsSixty-six patients died during the observation periods. The AUCs at 1, 6, 12, 24, and 36 months of the ACTION score were 0.942, 0.925, 0.889, 0.856, and 0.832; those of the CRUSADE score were 0.881, 0.883, 0.862, 0.876, and 0.862; and those of the GRACE score 0.949, 0.928, 0.888, 0.875, and 0.860, respectively.ConclusionsThe ACTION and GRACE scores were excellent risk stratification tools for mortality in the short term. The prognostic performance of each risk score was almost similar in the long term, but the CRUSADE score might be a superior risk stratification tool in the longer term than 3 years.

Abstract Increasing blood pressure variability (BPV) has been reported to be a strong predictor of cardiovascular events in patients with hypertension. However, the effects of BPV in the general population have not been intensively studied. The present study was designed to investigate a possible relationship between year‐to‐year BPV and hypertensive target organ damage (TOD) in a relatively low‐risk general population. A total of 5489 consecutive patients (mean age 58.6 ± 10.7 years) who visited our hospital for an annual physical checkup for five consecutive years during 2008–2013 were enrolled in this study. The average systolic and diastolic blood pressures and pulse pressure were calculated, as well as standard deviation, coefficient of variation, and average real variability in blood pressures. Cross‐sectional analysis was conducted and subjects without TOD at baseline (n = 3115) were followed up (median 1827 days) with the endpoint of TOD, defined as left ventricular hypertrophy on electrocardiogram or declining glomerular filtration rate. At baseline, BPV was closely associated with TOD. During follow‐up, left ventricular hypertrophy and declining glomerular filtration rate developed in 189 and 400 subjects, respectively. Although the standard deviation for systolic blood pressure and pulse pressure predicted future development of TOD in a univariate analysis, BPV was not a significant determinant of incident TOD in adjusted Cox hazard models. These results suggest that year‐to‐year BPV is a marker of the presence of TOD in the general population but does not independently predict future TOD.

We investigated the effects of chronic pre-exercise acetate administration on body weight and metabolic adaptations to endurance training in ICR mice fed with either a normal fat diet (NFD) or high fat diet (HFD), respectively. Mice were divided into a control group (Con), an acetate group (Ace), a training group (Tra), and an acetate+training group (Ace+Tra) with NFD or HFD, respectively. Mice received orally either water or acetate (72 mg/kg body weight/day) for 4 weeks. The mice in the training group were subjected to training using a treadmill (20–25 m/min×60 min, 5 times/week) immediately after administration. As a result, in the NFD mice, there was no effect of acetate in any of the measurements. In the HFD mice, the final body weight in the Ace, Tra and Ace+Tra groups was significantly lower than the Con group. Moreover, the acetate treatment tended to decrease blood glucose concentration at rest. Gastrocnemius muscle glycogen concentration in the Ace+Tra group was significantly higher than that of the Ace and Tra groups. Unexpectedly, a significant negative main effect of acetate treatment in the maximal activity of β-HAD was observed, though the endurance training increased enzyme activity of citrate synthase in the plantaris muscle. These findings show the possibility that acetate treatment with endurance training shifts the metabolic characteristics of mice toward a carbohydrate metabolism against a lipid metabolism with the HFD condition, but not with the NFD condition.

Because a large amount of beryllium is loaded into fusion reactors as a neutron multiplier, it is important to stably secure the beryllium resource, i.e., beryl ore (Be3Al2Si6O18), in order to realize fusion energy. The conventional method for extracting beryllium from beryl involves high-temperature processing steps, which may increase the cost and environmental risk. In view of this, a new wet process using microwaves at significantly lower temperatures was proposed. This study investigated the factors that enable the new wet process to achieve lower temperatures compared to the conventional method, and confirmed through tests that a chemical reaction occurs between beryl and NaOH at approximately 200 °C during the pretreatment process. It was found that this chemical reaction plays an important role in reducing the temperature of the process. The separation tests were performed to separate Al and Si from beryl minerals using this wet process, and the optimum conditions for each separation process were determined. Beryllium oxide and beryllium hydroxide were successfully recovered from the solution after Al and Si separation.

The purpose of this study was to evaluate the mechanical properties of beryllide (Be12Ti) fabricated by a plasma sintering method to provide important properties data for the material database for DEMO design. Single-phase Be12Ti powders were successfully fabricated by the homogenization treatment. Plasma sintering was performed using the homogenized powders at various temperatures to investigate the effect of sintering temperature on the density and microhardness of Be12Ti. The sintering density of Be12Ti increased with an increase in sintering temperature from 900 to 1000 °C and then saturated above 1000 °C. The sintering density was almost equal to the theoretical density. The variation in Vickers microhardness as a function of temperature was similar to that of sintering density. The fracture toughness values of Be12Ti calculated using Anstis, Evans and Charles, Tanakaequations, and Japanese industrial standards (JIS) R1607 criteria were approximately 2.16, 2.07, 2.00, and 2.43 MPa·m0.5, respectively.