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21.
Large lectures are the predominant way of teaching first-year students at universities in Norway. However, this forum for education is seldom discussed as a context for a formative feedback practice. The purpose of this sequential mixed methods study was to address whether and how a student-response system can open for a formative feedback practice in lectures and thereby support students' ability to monitor their own learning, as well as supply insight into how students engage with the feedback in their course work. The context for the study was large lectures (150–200 students) in a qualitative method course for first-year psychology students. Findings from the survey (n = 149) showed a positive correlation between the extent to which students report that they use clickers to monitor their own learning, and the extent to which they report that they used the feedback in their own course work. However, findings indicate that students valued the process of monitoring their own learning during the lectures to a greater extent than they actually used the feedback in their course work. Findings from interviews (n = 6) illustrated various ways students applied feedback in their course work. 相似文献
22.
23.
《Food Control》2015
The aim of this study was to evaluate the dietary exposure to fumonisin B1 (FB1) through determination of residual FB1 in hair and corn products consumed by 56 volunteers from Pirassununga and Erval Velho, Brazil. Data from FB1 analyses in corn products and a Food Frequency Questionnaire (FFQ) were used for estimating the mean probable daily intake (PDIM) for FB1. FB1 was detected in 4 human hair samples (7.2%), at a mean level of 21.3 ± 12.1 ng g−1. The mean FB1 level found in corn products was 360.4 ± 555.1 μg kg−1. The PDIM value of FB1 in volunteers was 159 ± 47 ng kg−1 body weight day−1 which represents 7.9% of the provisional maximum tolerable daily intake (PMTDI) recommended for fumonisins. The FB1 levels found in human hair samples from each volunteer were associated with their individual PDI of FB1, indicating that exposure to FB1 in the sample studied do not represent a health concern. This is the first report on the incidence of FB1 in individual human hair in Brazil. 相似文献
24.
文章分析了网络安全等级保护2.0时期国家标准的新变化对等级测评结论可能产生的影响,并用实际案例和数据论述了以往描述的基于测评指标和基于测评对象的定量分析方法存在的局限性。根据网络安全等级保护国家标准结构和内容的新特点,结合新的等级测评结论表述方法,文章提出了调整和优化定量计算产生等级测评结论的思路,给出了缺陷扣分的原理和缺陷扣分的定量计算方法,并比较了各种定量计算方法在计算结果上的差异,提出了适合新标准的测评结论定量计算公式。 相似文献
25.
ABSTRACTThis paper proposes the multiple-hypotheses image segmentation and feed-forward neural network classifier for food recognition to improve the performance. Initially, the food or meal image is given as input. Then, the segmentation is applied to identify the regions, where a particular food item is located using salient region detection, multi-scale segmentation, and fast rejection. Then, the features of every food item are extracted by the global feature and local feature extraction. After the features are obtained, the classification is performed for each segmented region using a feed-forward neural network model. Finally, the calorie value is computed with the aid of (i) food volume and (ii) calorie and nutrition measure based on mass value. The experimental results and performance evaluation are validated. The outcome of the proposed method attains 0.947 for Macro Average Accuracy (MAA) and 0.959 for Standard Accuracy (SA), which provides better classification performance. 相似文献
26.
《Food Control》2015
A telephone survey was carried out on 13,486 randomly selected households located in the Abruzzo region (central Italy). Three questionnaires were specifically designed in relation to three different groups of foods (Meat and meat products, Fishery products, Fruit and vegetables). Questions were mainly focused on the amount and number of purchases, type of retailer, and home food handling practices with respect to the week prior to the interview. Data were classified according to a multilingual thesaurus system (LanguaL). Results allowed to estimate domestic purchases (in kg) per capita for different food categories. The category “Red meat/Cattle” accounted for a large part of purchases in the “meat and meat products” group (10.9 kg per capita/year; 32.2% of purchases in the group) while the category “Fish or related organism/Fish” was the most purchased in the “fishery products” group (6.9 kg per capita/year; 63.3%). The aggregation of more detailed characteristics enabled the identification of popular categories of foods, such as “Red meat/Cattle/Divided into pieces” (25% of the “meat and meat products” group). Significant differences (p < 0.05) were found between the four different provinces (L'Aquila, Chieti, Pescara and Teramo) with respect to “Poultry/Chicken” and “Red meat/Cattle” categories. Householders were also asked about post-purchase food handling practices that might be hazardous to food safety. More than 20% of those surveyed stated that they thawed frozen meat at room temperature. The degree of doneness after cooking of different food categories was generally high: over 90% of products purchased in the majority of meat and fish categories were properly cooked. However a noticeable proportion of householders (about 15%) reported medium or rare cooking of “Red meat/Cattle” and “Red meat/Swine”. Differences (p < 0.05) were also found between consumers of different ages, with people over 65 years old being more prone to freeze meat and cook it thoroughly.The survey was carried out in a specific geographic area and on a statistically significant sample of households, thus allowing a collection of data on domestic habits relating to food purchases and home food handling practices. This information should be included in the framework of quantitative microbial risk assessment (QMRA) models as a measure of the actual exposure of consumers to pathogenic microorganism. The LanguaL system also proved to be a practical language-independent method useful not only to identify and describe food items but also to classify them according to specific food safety characteristics. 相似文献
27.
The standardization data for the California Verbal Learning Test-Second Edition (CVLT-II; D. C. Delis, J. H. Kramer, E. Kaplan, & B. A. Ober, 2000) were used to evaluate the base rate of 6 specific discrepancies between various key variables. The results indicated that CVLT-II performance discrepancies should equal or exceed 1 or 1.5 z score points (depending on the individual comparison) in the hypothesized direction to be considered potentially unusual. However, because about 1 in 3 persons in the standardization sample displayed at least 1 such large discrepancy, it is concluded that these base rates should be viewed only as a starting point for interpretation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
Nicolas Guerda; DeSilva Angela M.; Grey Kathleen S.; Gonzalez-Eastep Diana 《Canadian Metallurgical Quarterly》2006,37(6):702
Currently, ethnic and racial minority individuals represent a large proportion of the U.S. population, and researchers expect that they will represent the majority of the population by 2050. This shift in U.S. demographics calls for a greater awareness and integration of cultural issues into the assessment and treatment of ethnically and linguistically diverse clients. This article examines the unique beliefs and manifestations of illnesses among Haitians in connection with the American Psychological Association's (APA, 2002) Multicultural Guidelines. The authors use a common culture-bound syndrome, Séizisman, to illustrate the cultural beliefs, assessment, and treatment of illnesses among Haitians. In so doing, they demonstrate how to incorporate the APA Multicultural Guidelines into treatment with clients of diverse cultural and racial backgrounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
通过大量野外工程地质勘察与测试工作,在此基础上给出了横泉水库供水发电洞的工程地质分析与评价,从而使该水库的施工有了充分的理论依据。 相似文献
30.
介绍了金陵分公司常减压蒸馏装置改炼高硫原油扩能改造中采取的防腐蚀措施,主要有:①在易腐蚀部位选用耐腐蚀材料或复合材料;用螺杆压缩机回收三顶(常压塔顶、浅减压塔顶和深减压塔顶)气进行系统脱硫,彻底解决三顶气燃烧对炉管和热管的腐蚀以及对环境的污染问题.②施工中加强易腐蚀部位的焊缝检测和施工监督.③及时、合理调整"一脱三注"的化学药剂用量;高温部位增注高温缓蚀剂.④全员参与防腐蚀管理.⑤应用先进腐蚀在线监测系统和塔顶回流罐或产品罐pH值在线监测系统.该装置从2004年7月10日投产以来运行良好. 相似文献