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81.
Mother Parkers Tea & Coffee公司为咖啡袋包装业务增加了几台热转印打码机,以便能清晰地打印最新的日期。此举不但使咖啡生产线获得了最大限度的正常运行时间,而且为产品提供了可追溯性。  相似文献   
82.
83.
While it is generally accepted that the mobile cell phone has become ubiquitous within society for communicating, the actual use of the utilities on a phone have not been reported. Understanding how communication patterns are changing in society as a result of the mobile cell phone will enable the development and/or modification of existing cell phone utilities, the concept of privacy, and a mobile literacy research domain. To explore mobile cell phone utility use, 99 people completed a mobile phone usage questionnaire. Key results from the questionnaire are physical location when using a mobile cell phone, the length of communication episodes, the usage of phone utilities and existing privacy concerns related to mobile cell phones.  相似文献   
84.
Consumer focus groups in France, England, Sweden and Denmark were used to obtain insights into the decision-making involved in the choice of fresh pork and attitudes towards today's pig production systems. Many positive perceptions of pork meat were evoked. Negative images of the production systems in use today were expressed, but rationalised in terms of consumer demands, market competition and by comparisons to previous systems of production. Knowledge of production systems appeared of little consequence in terms of any meat market potential as several groups freely remarked that there was no link between the negative images of production methods and their purchase behaviour. The groups were clearly confused and mistrusted the limited information available at the point of purchase. Careful consideration should be given to meat labelling, in particular taking account of the evident consumer ethnocentrism, to assure that such information is targeted to enhance consumer confidence.  相似文献   
85.
The present study investigated taste preferences in a sample of 1705 children aged 6 to 9 years from survey centres in Italy, Estonia, Cyprus, Belgium, Sweden, Germany, Hungary, and Spain and aimed to identify factors correlated with taste preference. Children’s preferences for varying levels of sucrose (sweet) in apple juice and fat, sodium chloride (salt) and monosodium glutamate (umami) in crackers were assessed using paired-comparison tests. Socio-demographics (age, sex, parental education), early feeding practises (breastfeeding, introduction of fruits), parenting behaviour (TV viewing, using food as a reward) and taste threshold sensitivity for sucrose (sweet), sodium chloride (salt), caffeine (bitter) and monosodium glutamate (umami) were investigated as possible correlates of taste preferences. Parents reported on socio-demographics, early feeding and parenting behaviour. Taste thresholds were determined via a paired-comparison staircase method. Country of residence was the strongest factor related to preferences for all four tastes. Taste preferences also differed by age. Preference for sugar and salt increased between 6 and 9 years of age while preference for monosodium glutamate decreased. The age differences remained significant even after adjustment for sex, country of residence, parental education and early feeding habits. Sex, parental education, early feeding habits, TV viewing, using food as a reward and taste thresholds were not consistently related to taste preferences among the survey centres. In summary, the results highlight the importance of culture and age in taste preferences in children younger than 10 years of age.  相似文献   
86.
The SX Process program has been developed for modelling of extraction processes in centrifugal contactors where the transfer kinetics is of big importance due to the short hold up time. Apparent distribution ratios are calculated using a stage efficiency which is flow-rate independent. In this work the dependency of the stage efficiency on parameters affecting the extraction transfer rate, such as metal loading, O/A ratio and acidity, has been investigated in single stage centrifugal contactor experiments for extraction of americium(III) into a 0.015 M CyMe4-BTBP/0.25 M DMDOHEMA/octanol system. A model is proposed on how to calculate the stage efficiency and to accurately predict the apparent distribution ratios under the different conditions used.  相似文献   
87.
88.
We report on operant conditioning and artificial neural network (ANN) simulations aimed at further elucidating mechanisms of black-capped chickadee chick-a-dee call note category perception. Specifically, we tested for differences in the speed of acquisition among different discrimination tasks and, in two selected discrimination groups, searched for evidence of peak shift. Earlier, unreported ANN data were instrumental in providing the motivation for the current set of studies with chickadees and are provided here. The ANNs revealed differences in the speed of learning among note-type discrimination groups that is related to the degree of perceptual similarity among the three note types tested (i.e., A, B, and C notes). In many respects, bird and network results were in agreement (i.e., in the observation of peak shift in the same group), but they also differed in important ways (i.e., all discrimination groups showed differences in speed of learning in simulations but not in chickadees). We suggest that the start, peak and end frequency of the chick-a portion of chick-a-dee call notes, which form a graded but overlapping continuum, may drive the peak shift observed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
Many organic compounds including some herbicides concentrate in sediment, thus it may be expected that interstitial waters contain higher concentrations of these contaminants than the water column. To estimate benthic microalgal exposure to pesticides, sediment and interstitial water sampled in the dry season from four major rivers in north Queensland, Australia, were analysed for these contaminants. Interstitial water extracts from the sediments were tested for acute phytotoxicity to benthic microalgae using PAM fluorometry and the results were compared with chemical analyses of the same water samples. A range of pesticides were detected in both sediment and interstitial waters from all sites, notably the herbicide diuron at concentrations ranging from 0.3 to 11 μg kg−1 dry weight sediment, and up to 68 ng L−1 in interstitial waters. Herbicide concentrations estimated from partition coefficients and the sediment concentrations typically overestimated analytically determined concentrations present in interstitial water by an order of magnitude. The analytically determined herbicide concentrations in the interstitial water explained most of the phytotoxicity measured with the bioassay; however, photoinhibition was slightly higher than expected based on analytical results, indicating the presence of unidentified phytotoxins. These results demonstrate the presence of pesticides in interstitial waters in the Tropical dry season, sometimes at concentrations that may affect sensitive benthic organisms, and supports the use of the I-PAM bioassay as a valuable tool in exposure- and environmental risk- and impact-assessments.  相似文献   
90.
OBJECTIVE: To determine the relative risk of hip fracture associated with postmenopausal hormone replacement therapy including the effect of duration and recency of treatment, the addition of progestins, route of administration, and dose. DESIGN: Population based case-control study. Setting: Six counties in Sweden. SUBJECTS: 1327 women aged 50-81 years with hip fracture and 3262 randomly selected controls. MAIN OUTCOME MEASURE: Use of hormone replacement therapy. RESULTS: Compared with women who had never used hormone replacement therapy, current users had an odds ratio of 0.35 (95 % confidence interval 0.24 to 0.53) for hip fracture and former users had an odds ratio of 0.76 (0.57 to 1.01). For every year of therapy, the overall risk decreased by 6% (3% to 9%): 4% (1% to 8%) for regimens without progestin and 11% (6% to 16%) for those with progestin. Last use between one and five years previously, with a duration of use more than five years, was associated with an odds ratio of 0.27 (0.08 to 0.94). After five years without hormone replacement therapy the protective effect was substantially diminished (-7% to 48%). With current use, an initiation of therapy nine or more years after the menopause gave equally strong reduction in risk for hip fracture as an earlier start. Oestrogen treatment with skin patches gave similar risk estimates as oral regimens. CONCLUSIONS: Recent use of hormone replacement therapy is required for optimum fracture protection, but therapy can be started several years after the menopause. The protective effect increases with duration of use, and an oestrogen-sparing effect is achieved when progestins are included in the regimen.  相似文献   
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