Search

The study explores the relationship between phase angle (PhA), an indicator of cellular health, and metabolic health parameters among junior sumo wrestlers in Japan. Given the demanding lifestyle and high‐energy diets of sumo wrestlers that predispose them to metabolic syndrome post‐retirement, this study focuses on a younger cohort. The primary aim is to evaluate if PhA could serve as an early indicator of metabolic health issues within this unique demographic. A total of 14 sumo wrestlers aged 9–17 years were assessed to determine the relationship between PhA and various metabolic markers, including glycated hemoglobin (HbA1c), using a TANITA MC‐780A‐N body composition analyzer and standard blood tests. Bivariate regression analysis and Pearson's correlation revealed a negative relationship between PhA and HbA1c even after adjusting for age and weight (ß = −0.496, r2 = 0.776, r = −0.756, p = 0.004). The results indicate a significant negative relationship between PhA and HbA1c levels, suggesting that lower PhA values, which indicate poorer cellular integrity, are associated with higher HbA1c levels, signifying impaired glycemic control. These findings underscore the potential of PhA as a valuable biomarker for monitoring metabolic health in young sumo wrestlers, with implications for early intervention and management strategies. [ABSTRACT FROM AUTHOR]

Curling is a target‐based team sport played in a cold environment. The type of stress curling players face during a curling match remains to be determined. In the present study, 16 Japanese curling players performed a practice curling match (six ends lasting 90 min), wherein the following variables were documented: core and skin temperatures, heart rate, thermal sensation and comfort, urine‐specific gravity, body fluid loss, salivary cortisol, α‐amylase activity, salivary secretory immunoglobulin A (SIgA), and fractionated exhaled nitric oxide (FeNO, a respiratory stress marker). Pre‐match resting core temperature was 37.24 ± 0.31°C, which increased up to 37.73 ± 0.41°C during the match (p < 0.001). Facial skin temperatures decreased after the match (all p ≤ 0.015), whereas finger skin temperatures remained unchanged (p ≥ 0.375). Thermal discomfort increased following the match but thermal sensation remained unchanged. Following the match, players lost 0.29 ± 0.15 L body fluid (sweat, respiratory evaporation, and urine), which was nearly compensated by fluid ingestion of 0.22 ± 0.13 L (p = 0.119). Nevertheless, urine‐specific gravity increased from 1.021 ± 0.010 to 1.024 ± 0.008 after the match (p = 0.012), with 31% and 50% players being dehydrated at pre‐ and post‐match, respectively. Salivary cortisol decreased (p < 0.001) after the match without changes in salivary SIgA, α‐amylase activity, and FeNO (all p ≥ 0.113). Therefore, during a curling match, the core temperature and thermal discomfort increase, whereas the face skin temperature decreases. Additionally, players may undergo dehydration before the match, which could be exacerbated after the match. [ABSTRACT FROM AUTHOR]

Measurements of chemical compositions in the fog water at Murododaira (36.6°N, 137.6°E, altitude 2450 m), Mt. Tateyama, on the Sea of Japan side of central Japan, were performed mainly in autumn, and the characteristics of chemical climatology before 2010 and after 2017 were compared. Strong acid fogs that were sometimes detected before 2010 were not observed after 2017, and the pH of the fog water increased. Since 2017, the concentration of SO42− in the fog water has decreased significantly, and it has been observed that the fog water tends to be purified. There was no significant difference in the concentrations of ionic components except H+ and SO42− between before 2010 and after 2017. The nssSO42−/NO3− ratio in the fog water was high before 2010 but has decreased in recent years. The large reduction in SO2 emissions in China in the 2010s has had a major impact on the fog water chemistry at Mt. Tateyama. [ABSTRACT FROM AUTHOR]

The westerly wind travelling at high altitudes over eastern Asia transports aerosols from the Asian deserts and urban areas to downwind areas such as Japan. These longrange- transported aerosols include not only mineral particles but also microbial particles (bioaerosols), that impact the ice-cloud formation processes as ice nuclei. However, the detailed relations of airborne bacterial dynamics to ice nucleation in high-elevation aerosols have not been investigated. Here, we used the aerosol particles captured in the snow cover at altitudes of 2450m on Mt Tateyama to investigate sequential changes in the ice-nucleation activities and bacterial communities in aerosols and elucidate the relationships between the two processes. After stratification of the snow layers formed on the walls of a snow pit on Mt Tateyama, snow samples, including aerosol particles, were collected from 70 layers at the lower (winter accumulation) and upper (spring accumulation) parts of the snow wall. The aerosols recorded in the lower parts mainly came from Siberia (Russia), northern Asia and the Sea of Japan, whereas those in the upper parts showed an increase in Asian dust particles originating from the desert regions and industrial coasts of Asia. The snow samples exhibited high levels of ice nucleation corresponding to the increase in Asian dust particles. Amplicon sequencing analysis using 16S rRNA genes revealed that the bacterial communities in the snow samples predominately included plant associated and marine bacteria (phyla Proteobacteria) during winter, whereas during spring, when dust events arrived frequently, the majority were terrestrial bacteria of phyla Actinobacteria and Firmicutes. The relative abundances of Firmicutes (Bacilli) showed a significant positive relationship with the ice nucleation in snow samples. Presumably, Asian dust events change the airborne bacterial communities over Mt Tateyama and carry terrestrial bacterial populations, which possibly induce ice-nucleation activities, thereby indirectly impacting climate change. [ABSTRACT FROM AUTHOR]

Measurements of hydroperoxides (H2O2 and MHP) at ground level were made from 2012 to 2015 in Imizu City, Toyama Prefecture in central Japan. H2O2 and MHP concentrations ranged from 0.01 to 3.5 ppb and from below the level of detection (< 0.01 ppb) to 1.4 ppb, respectively. The concentrations of H2O2 and MHP were high in the summer and low in the winter. The H2O2 concentration was at its maximum in July and August, whereas the concentration of O3 in the daytime was highest in May and June. The ratio of [H2O2]/[SO2] presented clear seasonal variations. Many cases showed the condition of [H2O2] < [SO2], called oxidant limitation especially in the cold months. Hydroperoxide concentrations in the rainwater were also high in the summer. The concentrations of MHP were much lower than those of H2O2 in the rain water. High concentrations of H2O2 (> 2.5 ppb) were detected in the summer during the inflow of air pollution. The concentrations of H2O2 were significantly high in July and August of 2013. The H2O2 was well correlated with the O3 in July and August whereas there was no correlation between O3 and H2O2 in May and June. There was a negative correlation between NOX and H2O2. [ABSTRACT FROM AUTHOR]

The concentrations of hydroperoxides (H 2 O 2 and MHP), O 3 , SO 2 and NO X * over Imizu City, Toyama Prefecture, Japan were measured during summers using a helicopter. The concentrations of hydroperoxides were analyzed by an HPLC system within 5–10 min after the sampling. The H 2 O 2 concentration was lowest at the surface, and the highest concentration was detected at altitudes of 6000 and 8000 ft. The MHP was also higher in the high-altitude atmosphere. Significantly high concentrations of hydroperoxides were observed when air pollutants were transported from China. The concentration of H 2 O 2 was higher than that of SO 2 above 4000 ft where the potential capacity of SO 2 oxidation in the aqueous phase is large. A helicopter is useful for measuring of hydroperoxides in the high-altitude atmosphere using an HPLC system in a laboratory. [ABSTRACT FROM AUTHOR]

Wind solar towers constitute a fairly new scheme for harvesting renewable energy from solar and wind energy sources. In such a tower, solar radiation is collected and hot air is enforced to go fast through the tower, a process called thermal updraft, which fuels a wind turbine to generate power. Using vortex generators at the top of the tower creates a pressure difference, which increases the thermal updraft. In this work, we describe the setup of a wind solar tower system established at Kyushu University in Japan. Then, we demonstrate how data was collected from this system in order to train regression models for thermal updraft prediction. The feature selection process was guided by sensitivity analysis. After that, several machine learning models were investigated and the most suitable model was selected based on quality and time metrics. The linear regression model was particularly examined in detail, and was shown to have a satisfactory high accuracy of thermal updraft prediction graphically and numerically with a coefficient of determination of R 2 = 0.981. We also evaluated a reduced prediction model based on the six most essential features, which could be a reduced model description for the WST. This reduced model showed little performance degradation (R 2 = 0.974), with significant reduction in the needed effort and resources, as well as data collection requirements. [Display omitted] • Wind solar tower: renewable energy technique that combines powers from solar & wind. • Machine learning methods gained research momentum because of their prediction capabilities. • The linear regression model was accurately sufficient in predicting thermal updraft. [ABSTRACT FROM AUTHOR]

Wrestlers have a risk of relative energy deficiency in sports because they believe that they can gain an advantage over their opponents by temporarily adopting weight-making strategies even women. However, precise methods of making weight and the effect of manipulating body mass (BM) on health and performance in female wrestlers have not been reported. Our study aimed to report a case of weight making in a world-class female wrestler, who won the world competition seven times in 5-y and had oligomenorrhea. We obtained the BM, blood, urine, and saliva samples, hand grip strength, subjective condition a month before the match (baseline), and 3-d before the match (day-3), and food and physical activity records during baseline and 10 d before the competition. The wrestler lost 4.7% of BM from baseline to day-3 and 7.6% of BM to the match by method to reduce energy intake and enhance dehydration. Hand grip strength did not change by weight loss. After weigh-in, the wrestler took the recovery food containing 4.9 g/kg BM of carbohydrate. Although these weight strategies may at least contribute to the success of wrestlers, the impact on health needs to be clarified in future studies.

This study aimed to investigate the difference in the prevalence, severity, and risk factors of dysmenorrhea between Japanese female athletes and non-athletes in universities. The participants were 18 to 30 years old with no history of a previous pregnancy and/or childbirth. After application of the exclusion criteria, the cohort comprised 605 athletes and 295 non-athletes. An anonymous questionnaire, which included self-reported information on age, height, weight, age at menarche, menstrual cycle days, menstrual duration, dysmenorrhea severity, sleeping hours, dietary habits, exercise habits, training hours, and competition level was administered. Compared with athletes, non-athletes had a higher prevalence of dysmenorrhea (85.6% in athletes, 90.5% in non-athletes, p < 0.05); non-athletes also demonstrated increased severity (none/mild 27.8%, moderate 19.3%, and severe 52.9% in athletes; none/mild 21.2%, moderate 17.2%, and severe 61.6% in non-athletes; p < 0.05). Factors related to severe dysmenorrhea in athletes included long training hours, early menarche, and prolonged menstrual periods. In non-athletes, short menstrual cycle days and extended menstrual periods were related to severe dysmenorrhea. The prevalence and severity of dysmenorrhea were higher among non-athletes than among athletes; different factors were related to severe dysmenorrhea in these two groups. Thus, different strategies are necessary to manage dysmenorrhea for athletes and non-athletes in universities.