Sleep Duration and Overweight among Elementary Schoolchildren:A Population-based Study in Japan

Although a number of studies have investigated the relationship of sleep duration to overweight and obesity, studies conducted among population-based elementary schoolchildren have been limited in Japan. The aim of the present study was to investigate the relationship between sleep duration and overweight among elementary schoolchildren in Japan. The study subjects were all fourth-grade schoolchildren (9 or 10 years of age) in Ina-town, Saitama Prefecture, Japan from 1999 to 2008. Information concerning each subjectʼs sex, age, and lifestyle was obtained using a self-administered questionnaire, while measurements of his or her height and weight were carried out. Childhood overweight was determined according to the definition established by the International Obesity Task Force. Data from 3,433 children were analyzed. In logistic regression analysis, a statistically significant dose-response relationship was observed between sleep duration and overweight among boys (p for trend＝0.014) but not among girls (p for trend＝0.149). Short sleep duration was associated with childhood overweight, and the sex difference in the association was observed. These findings suggested that it is important to consider sleep duration as part of any program to prevent overweight among elementary schoolchildren, especially among boys

Enhanced Soybean Productivity by Inoculation With Indigenous Bradyrhizobium Strains in Agroecological Conditions of Northeast Germany

Commercial inoculants are often used to inoculate field-grown soybean in Europe. However, nodulation efficiencies in these areas are often low. To enhance biological nitrogen (N) fixation and increase domestic legume production, indigenous strains that are adapted to local conditions could be used to develop more effective inoculants. The objective of this study was to assess the ability of locally isolated Bradyrhizobium strains to enhance soybean productivity in different growing conditions of Northeast Germany. Three indigenous Bradyrhizobium isolates (GMF14, GMM36, and GEM96) were tested in combination with different soybean cultivars of different maturity groups and quality characteristics in one field trial and two greenhouse studies. The results showed a highly significant strain × cultivar interactions on nodulation response. Independent of the Bradyrhizobium strain, inoculated plants in the greenhouse showed higher nodulation, which corresponded with an increased N uptake than that in field conditions. There were significantly higher nodule numbers and nodule dry weights following GMF14 and GMM36 inoculation in well-watered soil, but only minor differences under drought conditions. Inoculation of the soybean cultivar Merlin with the strain GEM96 enhanced nodulation but did not correspond to an increased grain yield under field conditions. USDA110 was consistent in improving the grain yield of soybean cultivars Sultana and Siroca. On the other hand, GMM36 inoculation to Sultana and GEM96 inoculation to Siroca resulted in similar yields. Our results demonstrate that inoculation of locally adapted soybean cultivars with the indigenous isolates improves nodulation and yield attributes. Thus, to attain optimal symbiotic performance, the strains need to be matched with specific cultivars.Peer Reviewe

Eating Behavior and Childhood Overweight Among Population-Based Elementary Schoolchildren in Japan

This study investigated the relationship between eating behavior and childhood overweight among population-based elementary schoolchildren in Japan. Data was collected from fourth graders (9 or 10 years of age) from Ina Town, Saitama Prefecture, Japan from 1999 to 2009. Information about subjects’ sex, age, and lifestyle, including eating behaviors (eating until full and chewing thoroughly), was obtained using a self-administered questionnaire, and height and weight were measured directly. Overweight was determined according to the definition established by the International Obesity Task Force. Data from 4027 subjects (2079 boys and 1948 girls) were analyzed. Chewing thoroughly was associated with a significantly decreased odds ratio (OR) for being overweight, whereas eating until full significantly increased the OR for being overweight (OR: 1.50, 95% confidence interval: 1.16–1.94) among boys. However, eating until full was not associated with a significantly increased OR for being overweight among the group that reported chewing thoroughly, whereas it was associated with a significantly increased OR for being overweight (2.02, 1.38–2.94) among boys who did not chew thoroughly. In conclusion, eating until full or not chewing thoroughly was associated with being overweight among elementary schoolchildren. Results of this study suggest that chewing thoroughly may be an avenue to explore childhood overweight prevention efforts

Relationship of body mass index to percent body fat and waist circumference among schoolchildren in Japan - the influence of gender and obesity: a population-based cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Although the correlation coefficient between body mass index (BMI) and percent body fat (%BF) or waist circumference (WC) has been reported, studies conducted among population-based schoolchildren to date have been limited in Japan, where %BF and WC are not usually measured in annual health examinations at elementary schools or junior high schools. The aim of the present study was to investigate the relationship of BMI to %BF and WC and to examine the influence of gender and obesity on these relationships among Japanese schoolchildren.</p> <p>Methods</p> <p>Subjects included 3,750 schoolchildren from the fourth and seventh grade in Ina-town, Saitama Prefecture, Japan between 2004 and 2008. Information about subject's age, sex, height, weight, %BF, and WC was collected from annual physical examinations. %BF was measured with a bipedal biometrical impedance analysis device. Obesity was defined by the following two criteria: the obese definition of the Centers for Disease Control and Prevention, and the definition of obesity for Japanese children. Pearson's correlation coefficients between BMI and %BF or WC were calculated separately for sex.</p> <p>Results</p> <p>Among fourth graders, the correlation coefficients between BMI and %BF were 0.74 for boys and 0.97 for girls, whereas those between BMI and WC were 0.94 for boys and 0.90 for girls. Similar results were observed in the analysis of seventh graders. The correlation coefficient between BMI and %BF varied by physique (obese or non-obese), with weaker correlations among the obese regardless of the definition of obesity; most correlation coefficients among obese boys were less than 0.5, whereas most correlations among obese girls were more than 0.7. On the other hand, the correlation coefficients between BMI and WC were more than 0.8 among boys and almost all coefficients were more than 0.7 among girls, regardless of physique.</p> <p>Conclusions</p> <p>BMI was positively correlated with %BF and WC among Japanese schoolchildren. The correlations could be influenced by obesity as well as by gender. Accordingly, it is essential to consider gender and obesity when using BMI as a surrogate for %BF and WC for epidemiological use.</p

Bacillus Pumilus Strain TUAT-1 and Nitrogen Application in Nursery Phase Promote Growth of Rice Plants under Field Conditions

The aims of this study were to boost growth attributes, yield, and nutrient uptake of rice in paddy fields using a combination of Bacillus pumilus strain TUAT-1 biofertilizer and different nitrogen (N) application rates in nursery boxes. Bacillus pumilus strain TUAT-1 was applied as an inoculant biofertilizer in conjunction with different rates of N fertilizer to rice seedlings in a nursery. Plant growth and yield parameters were evaluated at two stages: in 21-day-old nursery seedlings and in mature rice plants growing in a paddy field. Inoculation with TUAT-1 significantly increased the seedling growth and root morphology of 21-day-old nursery seedlings. There was a marked increase in chlorophyll content, plant height, number of tillers, and tiller biomass of rice plants with the use of TUAT-1 and N fertilizers alone, and their combinations, at the maximum tillering stage in the field. The combination of TUAT-1 and 100% N (farmer recommended rate of N) resulted in the greatest tiller number and biomass at the maximum tillering stage, and positively affected other growth attributes and yield. The growth and yield were similar in the TUAT-1 + 50% N and 100% N (uninoculated) treatments, because TUAT-1 promoted root development, which increased nutrient uptake from the soil. These results suggest that the B. pumilus strain TUAT-1 has a potential to enhance the nutritional uptake of rice by promoting the growth and development of roots

Nitrous Oxide Emission from Organic Fertilizer and Controlled Release Fertilizer in Tea Fields

A field experiment was conducted for two years in the Green Tea Laboratory of Saitama Prefectural Agriculture and Forestry Research Center, Iruma, Saitama, Japan from March 2014 to December 2015. Controlled release fertilizers (CRF) or organic fertilizers (ORG), which are a mixture of chicken manure and oil cake, were applied with the amount of 450 kg·N·ha−1·year−1 in 2014 and 397 kg·N·ha−1·year−1 in 2015. Nitrous oxide (N2O) emissions from soil in green tea fields were measured by the closed chamber method. The results showed that CRF has significantly lower N2O compared to ORG. The cumulative N2O emissions from CRF accounted for 51% of N2O emissions from ORG fields and 138% of control with no fertilizer treatment. The N2O flux from the row was higher than that under the canopy, since fertilizer was applied on the row. However, the total emission from the area between the rows was lower than that under the canopy because the area ratio between the row and canopy was 1:5.Peer Reviewe