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Abstract: A polymer electrolyte fuel cell (PEFC) consists of a membrane electrode assembly (MEA), gas diffusion layers (GDL), hydrogen and oxygen supply channels. At the anode, protons and electrons are generated, while at the cathode the protons and electrons combine to form water. The condensed water may affect the fuel cell performance. In order to clarify the effect of water distribution on the PEFC performance, three-dimensional water distribution in the PEFC was visualized by using a neutron radiography facility at JRR-3 in JAEA. For observing the detailed water distribution, a small sized PEFC was designed. Size of the gas channel is 1mm width and 0.5mm depth. Thickness of the MEA and the GDL are about 50 and 200μm. The electrode area is 0.35×3.5cm2. The PEFC was set on an automatic rotating stage, and a picture was taken every 2.25° by using a cooled CCD camera with grey scale of 16bit. The exposure time was set at 15s. Using the 80 pictures which correspond to 180°, a computed tomography (CT) was carried out. In order to observe water distribution with high spatial resolution, the LiF scintillator with a thickness of 50μm was used. From the water distributions parallel and perpendicular to the MEA, existence of water around O-ring can be confirmed. However, the detailed distribution in the PEFC is difficult to obtain from the two-dimensional pictures. On the other hand, CT pictures make possible to obtain the three-dimensional water distribution. In this study, the spatial resolution of 76.5μm was achieved, and existence of water in the PEFC could be confirmed. [Copyright &y& Elsevier]

Objectives　Food environment improvement involving salt reduction requires improving access to and labeling low-sodium foods. Assessing the implementation status of these measures is also necessary. However, to date, no established methods exist for assessing the availability of low-sodium foods in communities. In this study, we aimed to devise a survey on the availability of low-sodium foods as a community food environment assessment method in order to establish common assessment methods, criteria, and practical measures, as well as standardization nationwide.Methods　A preliminary survey on the availability of low-sodium foods was conducted in Kitakyushu City in four stores with nationwide representation. Consent for providing information on handled product lists was obtained. The on-site lists collected through direct investigation by surveyors were compared with the handled product lists provided by the stores and analyzed to identify survey challenges and examine feasibility and the potential for accuracy. The definition of low-sodium foods, which emerged as a challenge in the preliminary survey, was confirmed. Preliminary survey data were carefully reviewed to establish classification criteria for low-sodium foods and create a low-sodium food list to serve as a reference for on-site surveys. Forms for recording the results of on-site surveys and a survey manual were developed. Registered dietitians conducted on-site surveys using the manual to confirm its applicability.Results　The preliminary survey results revealed that the on-site lists had fewer omissions and greater feasibility than store-provided lists. After clearly defining low-sodium foods, we established classification criteria (three major categories, seven subcategories, and 37 minor categories) considering the ease of on-site investigations and purchases. Three forms for recording survey results were developed, including a standard input form allowing detailed documentation of the availability of individual low-sodium foods, an aggregation form for a quantitative assessment of low-sodium foods availability, and a display form visualizing the availability of low-sodium foods by store. Furthermore, a survey manual was developed explaining the purpose and approach of the low-sodium foods availability survey, definition and classification criteria for low-sodium foods, and the three forms for recording survey results. Findings indicated that all registered dietitians could conduct on-site surveys using the manual and successfully collect and organize data.Conclusion　On-site surveys using the manual and documentation forms enabled easy and accurate assessments of low-sodium foods availability. Thus, this standardized method to assess the availability of low-sodium foods could be a food environment assessment method for regional salt reduction initiatives.

The objective of the present study was to describe the characteristics of pediatric burns in order to prepare a program for the prevention of severe burn injuries in children. We conducted a retrospective study of burn victims aged 15 years or younger who were hospitalized in our Critical Care Medical Center between 1982 and 1997. There were 73 children with burn injuries hospitalized in our center during the study period. The greatest number were children 1 year old. The average % body surface area burned was 21. 5+/-20.5%. The most important causes of pediatric burns were found to be hot bath water and other hot liquids. Hot bath scalds accounted for about half of the pediatric burns occurring in all age groups, and they were often extensive. Non-bath scalds accounted for about one-third of the pediatric burns and were most frequent in children 2 years and younger. All the injuries sustained at home occurred when a family member was in the house. Similar to many reports from overseas, non-bath scalds were one of the most common causes of burns in this study; however, hot bath scalds were the most important cause. These data are being used to develop a prevention program. We also consider it necessary to educate children and their family members about the dangers of burn injuries.

A retrospective study of bath-related burn injuries was carried out at our institution. A total of 216 patients with burns were admitted between 1982 and 1996. Bath-related burns were identified in 58 patients (26.9%). The number of patients with bath-related burns increased throughout the study period. The percentage body surface area burned was 43.8 +/- 25.7% in the bath-related burn group and 27.3 +/- 28.3% in the bath-unrelated burn group. This difference was significant. There was no significant difference between the two groups with respect to mortality rate. The mechanism by which the patients sustained a bath-related burn clearly differed according to age. The percentage of burns which are bath-related and the severity of bath-related burns are higher in Japan than in any other country. This can be attributed to lifestyle, bathing systems, bathroom architecture, housing conditions and an increase in the elderly population. These burns can be prevented. Education based on this study will play a critical role in the prevention of the bath-related burn injuries.