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991.
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Michael A. Stefanone Kyounghee Hazel Kwon Derek Lackaff 《Journal of Computer-Mediated Communication》2012,17(4):451-466
Online social networking sites enable users to connect with large, heterogeneous groups of people. While extant research suggests individuals benefit psychologically from the perception that they are well connected, little is known about the nature of tangible resources embedded in these online networks. In this study 49 participants sent 588 requests for instrumental help to their Facebook friends to determine the accessibility of networked resources and online social capital. Almost 80% of these modest requests went unanswered, and perceived bridging and bonding capital did not explain enacted support. However, people who occupied socially prestigious positions were the most likely to benefit from their friend's help. These results suggest that expansive mediated networks may yield limited instrumental benefits. 相似文献
994.
Statistical tolerance intervals are often used during design verification or process validation in diverse applications, such as the manufacturing of medical devices, the construction of nuclear reactors, and the development of protective armor for the military. Like other statistical problems, the determination of a minimum required sample size when using tolerance intervals commonly arises. Under the Faulkenberry-Weeks approach for sample size determination of parametric tolerance intervals, the user must specify two quantities—typically set to rule-of-thumb values—that characterize the desired precision of the tolerance interval. Practical applications of sample size determination for tolerance intervals often have historical data that one expects to closely follow the distribution of the future data to be collected. Moreover, such data are typically required to meet specification limits. We provide a strategy for specifying the precision quantities in the Faulkenberry-Weeks approach that utilizes both historical data and the required specification limits. Our strategy is motivated by a sampling plan problem for the manufacturing of a certain medical device that requires calculation of normal tolerance intervals. Both classical and Bayesian normal tolerance intervals are considered. Additional numerical studies are provided to demonstrate the general applicability of our strategy for setting the precision quantities. 相似文献
995.
Renee Korczak Derek Timm Rylee Ahnen William Thomas Joanne L. Slavin 《Journal of food science》2016,81(9):S2240-S2245
This study compared satiety after high protein pasta (16 g protein, 6 g fiber), high fiber pasta (11 g protein, 8 g fiber) or control pasta (11 g protein, 6 g fiber) in a randomized, placebo‐controlled, double‐blind crossover trial. Participants were 36 healthy and men and women from the University of Minnesota campus. Fasted men and women ate calorie controlled, but macronutrient different pastas at 12:00 pm along with 500 mL of water. The primary outcome was satiety assessed by Visual Analogue Scales at 0, 15, 30, 45, 60, 90, 120, and 180 min daily after consuming the pastas. Secondary outcomes were calories consumed at an ad libitum snack at 3:00 pm, calories from food intake, gastrointestinal tolerance, and palatability. No differences were found among the pasta treatments for satiety, snacking, or gastrointestinal tolerance. Men ate significantly more calories for the rest of the (P = 0.007) after the high protein pasta versus the high fiber pasta (1701 ± 154 compared with 1083 ± 154) with control pasta being intermediate to the other treatments. No significant differences were found for gastrointestinal tolerance, but the palatability ratings showed the high protein pasta was less tasty (P = 0.03) and less pleasant (P = 0.01) than the other 2 pastas. Satisfaction was positively associated with pleasantness and negatively associated with aftertaste. Our results do not support the idea that high protein or high fiber pasta produces a greater satiety response compared to pasta with lower amounts of either nutrient. It is likely that since pasta is already a very satiating food, the subjects were unable to differentiate between the 3 conditions. 相似文献
996.
Application of the fast sensory method ‘Rate‐All‐That‐Apply’ in chocolate Quality Control compared with DHS‐GC‐MS 下载免费PDF全文
Sandra S. Waehrens Shujuan Zhang Pia I. Hedelund Mikael A. Petersen Derek V. Byrne 《International Journal of Food Science & Technology》2016,51(8):1877-1887
This paper studied the fast sensory Rate‐All‐That‐Apply (RATA) method as a contributor to existing quality control (QC) in chocolate production by comparing it with the outcome of dynamic headspace sampling combined with gas chromatography–mass spectrometry (DHS‐GC‐MS). Seven different chocolates were evaluated by a semi‐trained panel using RATA. RATA showed potential as a sensory evaluation tool which could be part of QC programmes in chocolate production as RATA was efficient to perform and captured important sensory deviations, herein addition of excess lecithin and prolonged roasting. However, product deviations caused by long conching were only detected by DHS‐GC‐MS. A more extreme conching process must occur before it can be perceived by humans. RATA and DHS‐GC‐MS should be used as complementary methods in detecting future important issues in chocolate production. DHS‐GC‐MS detects product deviation from chemical perspectives while sensory evaluation gives information on quality parameters from a perceivable perspective influencing consumer satisfaction. 相似文献
997.
998.
Christine E. Sleeter. (1996). Multicultural education as social activism. Albany: State University of New York Press. ISBN 0–7914–2998–9 相似文献
999.
Rigét F Braune B Bignert A Wilson S Aars J Born E Dam M Dietz R Evans M Evans T Gamberg M Gantner N Green N Gunnlaugsdóttir H Kannan K Letcher R Muir D Roach P Sonne C Stern G Wiig O 《The Science of the total environment》2011,409(18):3520-3526
A statistically robust method was applied to 83 time-series of mercury in Arctic biota from marine, freshwater and terrestrial ecosystems with the purpose of generating a ‘meta-analysis’ of temporal trend data collected over the past two to three decades, mostly under the auspices of the Arctic Monitoring and Assessment Program (AMAP). Sampling locations ranged from Alaska in the west to northern Scandinavia in the east. Information from recently published temporal trend studies was tabulated to supplement the results of the statistical analyses. No generally consistent trend was evident across tissues and species from the circumpolar Arctic during the last 30 years or so. However, there was a clear west-to-east gradient in the occurrence of recent increasing Hg trends, with larger numbers and a higher proportion of biotic datasets in the Canadian and Greenland region of the Arctic showing significant increases than in the North Atlantic Arctic. Most of the increasing datasets were for marine species, especially marine mammals. A total of 16 (19%) out of the 83 time-series could be classified as “adequate”, where adequate is defined as the number of actual monitoring years in a time-series being equal to or greater than the number of years of sampling required to detect a 5% annual change in Hg concentrations, with a significance level of P < 0.05 and 80% statistical power. At the time of the previous AMAP Assessment, only 10% of the Hg time-series were deemed adequate. If an additional 5 years of data were to be added to the current set of time-series, it is predicted that 53% of time-series would become adequate. 相似文献
1000.
Age thickening is a well known phenomenon within the dairy industry, where the apparent viscosity of concentrated dairy solutions increases with storage time under low shear. The objective of the paper is to develop new tools to analyse several aspects of age thickening, including the increases in shear thinning, the degree of thixotropy and the rate of structural build up with time, as well as irreversible structural changes and gelation. The build up of the dispersed phase structure during storage, was captured by a snap shot technique, where concentrated milk samples were stored, and aliquots were taken at periodic intervals and subjected to shear sweep tests to collect flow curves. Rheological modelling using the Herschel-Bulkley model showed an increase in yield stress and consistency, indicating a build up in structure during age thickening. The trend in apparent viscosity with storage time showed two-phases, a slow and steady increase followed by a sharp rise, which could be used to identify the onset of firm gelation. The extrapolated viscosity at infinite shear rate increased with storage time, indicating the build up in irreversible structural components during age thickening. 相似文献