University of Tsukuba

About: University of Tsukuba is a education organization based out in Tsukuba, Ibaraki, Japan. It is known for research contribution in the topics: Population & Gene. The organization has 36352 authors who have published 79483 publications receiving 1934752 citations. The organization is also known as: Tsukuba daigaku & Tsukuba University.

Thermal Effects of Urban Canyon Structure on the Nocturnal Heat Island: Numerical Experiment Using a Mesoscale Model Coupled with an Urban Canopy Model

Abstract: A single-layer urban canopy model is incorporated into a simple two-dimensional atmospheric model in order to examine the individual impacts of anthropogenic heating, a large heat capacity, and a small sky-view factor on mesoscale heat island formation. It is confirmed that a nocturnal heat island on a clear, calm summer day results from the difference in atmospheric stability between a city and its surroundings. The difference is caused by anthropogenic heating and the following two effects of urban canyon structure: (i) a larger heat capacity due to the walls and (ii) a smaller sky-view factor. Sensitivity experiments show that the anthropogenic heating increases the surface air temperature though the day. (This factor strongly affects the nocturnal temperature, and the maximum increase of 0.67°C occurs at 0500 LST.) The larger heat capacity due to the walls decreases the daytime temperature and increases the nocturnal temperature. (The maximum increase of 0.39°C occurs at 0600 LST.) The smalle...

Association between climate variability and hospital visits for non-cholera diarrhoea in Bangladesh: effects and vulnerable groups

Abstract: We estimated the effects of rainfall and temperature on the number of noncholera diarrhoea cases and identified population factors potentially affecting vulnerability to the effect of the climate factors in Dhaka Bangladesh. Weekly rainfall temperature and number of hospital visits for non-cholera diarrhoea were analysed by time-series regression. A Poisson regression model was used to model the relationships controlling for seasonally varying factors other than the weather variables. Modifications of weather effects were investigated by fitting the models separately to incidence series according to their characteristics (sex age socio-economic hygiene and sanitation status). The number of non-cholera diarrhoea cases per week increased by 5.1% (95% CI: 3.3-6.8) for every 10mm increase above the threshold of 52mm of average rainfall over lags 0-8 weeks. The number of cases also increased by 3.9% (95% CI: 0.6-7.2) for every 10mm decrease below the same threshold of rainfall. Ambient temperaturewas also positively associated with the number of noncholera diarrhoea cases. There was no evidence for the modification of both high and low rainfall effects by individual characteristics while the effect of temperature was higher amongst those individuals at a lower educational attainment and unsanitary toilet users. The number of non-cholera diarrhoea cases increased both above and below a threshold level with high and low rainfall in the preceding weeks. The number of cases also increased with higher temperature particularly in those individuals at a lower socio-economic and sanitation status. (authors)

Variations in the FTO gene are associated with severe obesity in the Japanese

Abstract: Variations in the fat-mass and obesity-associated gene (FTO) are associated with the obesity phenotype in many Caucasian populations. This association with the obesity phenotype is not clear in the Japanese. To investigate the relationship between the FTO gene and obesity in the Japanese, we genotyped single nucleotide polymorphisms (SNPs) in the FTO genes from severely obese subjects [n = 927, body mass index (BMI) ≥ 30 kg/m2] and normal-weight control subjects (n = 1,527, BMI < 25 kg/m2). A case-control association analysis revealed that 15 SNPs, including rs9939609 and rs1121980, in a linkage disequilibrium (LD) block of approximately 50 kb demonstrated significant associations with obesity; rs1558902 was most significantly associated with obesity. P value in additive mode was 0.0000041, and odds ratio (OR) adjusted for age and gender was 1.41 [95% confidential interval (CI) = 1.22–1.62]. Obesity-associated phenotypes, which include the level of plasma glucose, hemoglobin A1c, total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, and blood pressure were not associated with the rs1558902 genotype. Thus, the SNPs in the FTO gene were found to be associated with obesity, i.e., severe obesity, in the Japanese.