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301.
This paper shares the findings of an active transportation (AT) study conducted in the context of a city in a developing country. First, a list of AT indicators was developed based on the literature review and expert opinion survey. Second, a face-to-face survey was conducted to collect information on individuals' socio-demographic characteristics, travel behavior, AT mode choice, and their perceptions regarding the AT conditions in their neighborhoods. Analysis of the survey results suggests that several socio-demographic characteristics are associated with AT use. For example, young adults and individuals with low income are the primary users of AT. Also, results suggest that students are mainly active commuters. The ratio of AT use increases with the number of bicycles in the household. Individuals tend to walk more when travel duration is less than 10 minutes. Educational areas are perceived as safer and convenient areas for using active modes of transport compared to other land-use types. Also, a higher proportion of active commuters perceive local roads to be safer from vehicular traffic compared to main roads. Many sectors such as planning, transportation, health, and education as well as non-government organizations will be benefited from this study. 相似文献
302.
Kazufumi?OsakoEmail author Mohammed?Anwar?Hossain Koichi?Kuwahara Yukinori?Nozaki 《Fisheries Science》2005,71(2):367-373
The cryoprotective effects of trehalose on fish myofibrillar protein were compared with those of sucrose, glucose and sorbitol.
The frozen surimi with trehalose exhibited significantly higher Ca2+-ATPase activity through-out the storage periods, resulting in higher gel-forming ability than that of without trehalose.
The amount of unfrozen water was significantly increased in the surimi upon addition of trehalose at any concentrations tested.
The findings suggest that trehalose constructed bound water molecules in protein structure, consequently suppressed freeze-induced
denaturation of protein and maintained gel-forming ability. An addition of 5.0% to 7.5% concentration of trehalose showed
threshold behavior to increase the amount of unfrozen water and to prevent freeze-induced denaturation of protein. The effects
of trehalose were almost similar to those of other sugars. 相似文献
303.
1. Little is known about the ability of farmed poultry to digest chitin and derive nutrients from the ingestion of insects. 2. Commercial chitin derived from crustacean shell waste was found to contain 373 g crude protein, 265 g ash, 23.5 g ether extract, 130 g calcium and 16.4 g phosphorus per kg, on an air-dry basis. 3. It was included in diets at 0, 25, 50 and 75 g chitin per kg and fed to 320 1-d-old broiler males, over a 21-d period. There were no statistically significant treatment effects on weight gain or feed efficiency. Apparent digestibility of chitin protein was 0.48, 0.50 and 0.45, at the 25, 50 and 75 g per kg inclusions, respectively. Mean AME and AMEN values of chitin were determined as 8.97 and 8.86 MJ/kg. 4. In a subsequent study, mean TME and TMEN values of chitin were determined to be 8.23 and 8.21 MJ per kg, respectively. Addition of chitinase to the diet increased TME and TMEN of chitin to 8.81 and 8.79 MJ per kg, respectively (P<0.05). True digestibility of chitin protein was determined to be 0.87. 5. Triglyceride concentrations in liver and breast meat were significantly reduced by chitin inclusion. No significant differences in carcase yield at 21 d of age were found. Serum cholesterol and triglycerol concentrations were reduced significantly by dietary chitin, the lowest levels being observed at the 50 g per kg inclusion level. 6. These findings indicate the ability of modern poultry to digest chitin but suggest that the ingestion of insects is not an important source of nutrients, at least from the exoskeleton. 相似文献