Objective: The purpose of this study is to delineate the association between residents’ perception of the neighborhood’s environments and walking time in objectively different regions in Japan.
Methods: Two regions were selected as high and low walkable regions on the basis of differences in their residential density, mixed land use and street connectivity. The subjects in this study were participants in a health promotion program focused on walking sponsored by local governments. A questionnaire was sent to the participants asking about how their perception of the neighborhood’s environment related to walking, and the time spent walking per week. There were 237 residents from the high walkable region and 195 from the low walkable region who completed the study survey.
Results: The high walkable region had a larger residential density, a high mixed land use and a higher street connectivity than the low walkable region. Walking time, and the scores of the perception of the neighborhood’s environment for the high walkable region residents were significantly higher than those for the low walkable region residents. Thus, residents’ perception of the neighborhood’s environment generally reflected the actual physical environmental characteristics. Residents in the high walkable region whose scores for accessibility and aesthetics were high, spent significantly more walking time. Residents in the low walkable region whose scores for accessibility, safety, convenience and aesthetics were high, spent significantly more walking time.
Conclusion: The study results suggested that the neighborhood’s environment may influence daily walking time. The perceptions of the neighborhood’s environmental factors that correlate with walking times differ between the different regional physical environments. Therefore, to promote physical activity, the consideration of environmental factors unique to residents’ neighborhood’s environments is needed.

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Objectives: Sumo wrestling is one of the most popular sports in Japan. Injuries are not uncommon as this is a vigorous contact sport. Sumo wrestlers have little in the way of protective clothing; their main garb is the mawashi, making them prone to exposure to any microorganisms in the dohyo. The bacterial flora of the dohyo has received little attention. If the constituent flora is identified, then appropriate treatment or prevention of any bacterial lesions or infections incurred by the wrestlers is possible.
Methods: The Vitek AMS system used in this study was developed by McDonnell Douglas Corporation. In this system, the physiological and biochemical properties of Gram-positive and -negative bacilli, Gram-positive and -negative cocci, and fungi isolated from clinical materials and environments are examined using test cards specifically for each microorganism group, and the results are automatically read by a computer and encoded. Obtained codes are compared with a built-in database, and bacterial species of test strains are identified.
Results: In this study, using the automatic identification kit VITEK or ATB, we describe the aerobic bacterial flora found in the dohyo over the four seasons of the year. We also investigated the effect of salt on the bacterial flora as sumo wrestlers toss salt on the dohyo before each match. We show the relationship between salinity changes and variations in the flora observed upon the addition of salt. Without salt, at the beginning of a match, Gram-negative bacteria predominate. When salt is added, there is a transient decrease in the incidence of flora followed by an increase in the incidence Gram-positive cocci.
Conclusions: Sixteen bacterial genera were identified using the bacterial identification systems in dohyo soil samples during the year. The number of identified bacterial species was 32. Even in the presence of salt, there is a measurable amount of bacterial flora in dohyo soil; salt does not act as an antibacterial agent.

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Objectives: To examine nonylphenol (NP) and 4-t-octylphenol (OP) concentrations and general water quality indicators along a river in the greater Tokyo area and to specify the distribution and origin of alkylphenols.
Methods: Water was sampled from the Edogawa River, a main river in the greater Tokyo area, which is a source of public drinking water; and the Sakagawa River system, a tributary of the Edogawa River. To determine alkylphenol in river water, NP and OP concentrations were quantified using gas chromatography-mass spectrometry (GC-MS).
Results: The detection rates of NP above the detection limit were 100% in both rivers, and those of OP were 75.0% in the Edogawa River and 92.9% in the Sakagawa River system. The median NP and OP concentrations in the Edogawa River were 0.24 μg/l and 0.066 μg/l, and those in the Sakagawa River system were 0.87 μg/l and 0.19 μg/l respectively. Alkylphenol concentrations are significantly higher in the Sakagawa River system than in the Edogawa River. In the Sakagawa River system, the NP and OP concentrations were highest in the water along the nonindustrial area with an underdeveloped sewerage system.
Conclusions: NP and OP were detected widely in the Edogawa River and Sakagawa River system. Endocrine-disrupting chemical (EDC) pollution in a river by the inflow of urban wastewater was demonstrated. A systematic monitoring of alkylphenols in tributary rivers and streams as well as in main rivers will help control EDC pollution and protect the source of drinking water in urban areas.

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Objective: The purpose of this study was to clarify the relationships among fall risk, physical activity habits, and ADL capability in a community-dwelling Japanese elderly population.
Methods: The subjects were 1,407 Japanese aged 65 or older (604 males, 803 females). Fall risk was evaluated using the Falling Assessment Chart of Suzuki et al. (2003). Physical activity habits such as the frequency of leaving the house, the use of transportation, the frequency of physical exercise, and interests were evaluated. ADL capability was evaluated using the Tokyo Metropolitan Institute of Gerontology Index of Competence.
Results: Approximately 25% of the subjects had a high fall risk (score of 5 or more). Fall risk increased with age and ADL capability decreased with age. The group with a low fall risk (score <5) had a significantly higher ADL capability than the group with a high fall risk (score ³5). From results of two-way ANCOVA (gender×physical activity habits) with age as the covariate, the fall risk of people who regularly go on leaving the house, exercise, and have interests tended to be low. Further more, the relationships between the scores and physical activity habits were examined by two-way ANCOVA with age and ADL capability as the covariates. There were significant differences in the frequency of leaving the house, and elderly persons who leaved regularly the house, had a low fall risk.
Conclusions: This study showed that fall risk is closely related to ADL capability, and that the frequency of leaving the house is very important for reducing fall risk.

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Objective: The aim of this study is to clarify the long-term dynamics of the red tide occurring in Lake Kawaguchi.
Methods: The measurement of environmental factors and water sampling were carried out monthly at a fixed station in Lake Kawaguchi’s center basin from April 1993 to March 2004. On June 26, 1995, the horizontal distribution of Peridinium bipes was investigated using a plastic pipe, obtaining 0~1-m layers of water column samples at 68 locations across the entire lake.
Results: P. bipes showed an explosive growth and formed a freshwater red tide in the early summer of 1995, when the nutrient level was higher than those in the other years, particularly the phosphate concentration in the surface layer. The dissolved total phosphorus (DTP) concentration was sufficient for P. bipes growth in that year. In the study of its horizontal distribution, P. bipes was found at all the locations. The numbers of cells per milliliter ranged from 67 to 5360, averaging 1094±987 cells/ml, with particularly high densities along the northern shore. Since then, P. bipes has annually averaged about 25 cells/ml in Lake Kawaguchi.
Conclusion: We observed that the red tide caused by P. bipes correlates with a high DTP concentration in Lake Kawaguchi.

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