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KRISTINE O. EVANS LOREN W. BURGER JR. BRANT C. FAIRCLOTH WILLIAM E. PALMER JOHN P. CARROLL 《The Journal of wildlife management》2009,73(7):1241-1244
ABSTRACT We assessed effects of tissue collection methods (i.e., patagial microbiopsy and down feathers) and chick age at sampling on morphometrics and 21-day survival of 600 captive neonatal northern bobwhite (Colinus virginianus). We observed minimal effects on morphometrics and no difference in survival among patagial microbiopsy (x̄ = 0.96 ± 0.03), down feathers (x̄ = 0.92 ± 0.04), and control (x̄ = 0.86 ± 0.05) methods. DNA analysis from patagial microbiopsy, down feather, and egg tooth samples showed greater concentrations of DNA from patagial microbiopsy (x̄ = 10.28 ± 1.74 μg/ml) than either down feather (x̄ = 4.10 ± 1.74 μg/ml) or egg teeth (x̄ = 2.35 ± 1.74 μg/ml). 相似文献
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Daily studies were made of the osmoregulatory abilities of Cardisomaguanhumi from hatching to the end of larval development. Theseresults were compared to those of similar research on osmoregulationby larvae and megalopa of four species of estuarine, littoral,and sub-littoral crabs. The comparison shows that larvae ofC. guanhumi possess the same kinds of adaptations for waterintake at the time of molt that were found in Rhithropanopeusharrisii. Land-crab larvae hyperregulated in 10 p.p.t. sea waterand hyporegulated in water of 40 p.p.t. for experimental periodsfor 2 hr during the first one-third of their development. Duringthe remainder of larval life, they hyporegulated against 15p.p.t. in intermolt periods and became isosmotic with, or hyporegulatedagainst, 10 p.p.t. at the time of molting. From the time ofhatching, the osmoregulatory pattern of developing C. guanhumifits them for deep penetration of estuaries and for crossingsteep saline gradients. This pattern is evidence for a strongerand more enduring control of water balance, especially at thetime of molting, than we have found in non-terrestrial species. 相似文献
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M. C. GACULA JR. R. W. WASHAM II S. A. BEARD J. E. HEINZE 《Journal of sensory studies》1986,1(1):47-53
In-house use consumer test data from four studies dealing with three pairs of household products and a pair of antiperspirant products were examined for significant carry-over (product usage order) effects, which would confound the analysis of treatment (product) effects. In each study, two products were compared using a two-period crossover design. One hundred twenty panelists participated in each study. A forced choice preference scale or a 9-point hedonic scale was used to obtain responses from various sensory attributes. In all studies, the estimates of carry-over effects were not significant at the 5% level. Transformation of hedonic scale data into preference dichotomy also gave estimates of carry-over effects which were not significant at the 5% level, but led to a loss of test sensitivity for detecting treatment differences. The authors recommend that all comparative crossover design studies in sensory evaluation be monitored for carry-over effects and that statistically determined sample size should be used to reduce the possibility of obtaining significant carry-over effects. 相似文献
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PETER L. BORDI JR. DANIELLE M. HACK SUSAN J. COCCI MICHELE D. RAGER S. WILLIAM HESSERT JR. 《Journal of sensory studies》2009,24(1):41-57
This is an initiative study on the use of trans -fat-free products in the bakery industry. A standardized doughnut product was cooked in three doughnut shortenings, one containing trans fat and two that were trans fat-free. Six hundred forty-one panelists, students, faculty and staff of a large northeastern university rated each of the three doughnuts on a variety of categories, including texture, moisture content and overall liking. Results showed that there were no significant differences between doughnuts cooked in the three shortenings – this was true for all attributes tested.
The results from this study have many significant implications for the foodservice industry, as they work to cut down or eliminate the use of trans fats in their establishments because of the significant health risks they have been proven to cause.
This study demonstrates the variances on texture, taste, appearance and overall liking characteristics of doughnuts fried in different doughnut shortenings. The nutritional breakdown of the doughnuts and the shortenings are also addressed. In the case of shortenings, the ideal type of fat is a mixture of canola, soybean and hydrogenated cottonseed. This shortening mixture, which is trans fat-free, produced the most preferred doughnut. 相似文献
The results from this study have many significant implications for the foodservice industry, as they work to cut down or eliminate the use of trans fats in their establishments because of the significant health risks they have been proven to cause.
PRACTICAL APPLICATIONS
This study demonstrates the variances on texture, taste, appearance and overall liking characteristics of doughnuts fried in different doughnut shortenings. The nutritional breakdown of the doughnuts and the shortenings are also addressed. In the case of shortenings, the ideal type of fat is a mixture of canola, soybean and hydrogenated cottonseed. This shortening mixture, which is trans fat-free, produced the most preferred doughnut. 相似文献