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The inhibitory effects of Lactobacillus plantarum-fermented and non-fermented Inula britannica extracts on the tyrosinase activity were comparatively investigated to examine whether and how they improve the whitening activity, and the contents of total flavonoids and polyphenolics as bioactive compounds were determined. The skin whitening activity using in vitro or ex vivo tyrosinase and L-3,4-dihydroxyphenylalanine (L-DOPA) staining was examined. The total flavonoid content (TFC) was increased by 13.4% after 72 h-fermentation. The viabilities of the B16F10 cells treated with the fermented and non-fermented control extracts were 100.26% and 92.15% at 500 μg/ml, respectively. In addition, the inhibition of tyrosinase activity was increased by the fermented samples from 29.33% to 41.74% following fermentation for up to 72 h. The tyrosinase activity of the untreated control group was increased to 145.69% in B16F10 cells. The results showed that I. britannica fermented by L. plantarum dose-dependently inhibited tyrosinase activity, which was stimulated by α-melanocyte stimulating hormone. These results suggest that lactic fermented I. britannica extracts can be used as effective skin-whitening materials.  相似文献   
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This study was designed to examine the effects of the competency (low vs. high) and interaction type (proactive vs. responsive) of pedagogical agents as learning companions (PALs) on learning, self-efficacy, and attitudes. Participants were 72 undergraduates in an introductory computer-literacy course who were randomly assigned to one of four treatments: Low-Proactive, Low-Responsive, High-Proactive, and High-Responsive. Results indicated a main effect for PAL competency. Students who worked with the high-competency PAL in both proactive and responsive conditions achieved higher scores in applying what they had learned and showed more positive attitudes toward the PAL. However, students who worked with the low-competency PAL reported significantly enhanced self-efficacy beliefs in the learning tasks. Also, there was a main effect far PAL interaction type. A proactive PAL had a significantly positive impact on recall. These different results on learning and motivational outcomes suggest that the competency and interaction type of a PAL should be designed according to the desired learning and motivational goals.  相似文献   
54.
An efficient method for tracing planar implicit curves   总被引:1,自引:0,他引:1  
INTRODUCTION Tracing a planar implicit curve f(x, y)=0 on a rectangular region [xl, xr]×[yb, yt] is of great interest in Computer-Aided Design and Computer Graphics. While parametric curves are easy to plot, plotting implicit curves is a challenging problem. Planar im- plicit curve plotting method can be classified into two categories (Shou et al., 2005; Martin et al., 2002; Lopes et al., 2002). In the first category are subdivi- sion methods (Shou et al., 2005; Martin et al., 2002) …  相似文献   
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This article was first drafted after I worked for 14 weeks last year in a school that was piloting the National Literacy Strategy at Key Stage 3. I now work in another school delivering the full published Strategy to Year 7. In this article, I explore the contradictions inherent in the Strategy in attempting to develop the English and literacy skills of Key Stage 3 pupils. Ultimately, my argument is that the educational benefits of this teaching to objectives is at odds with some of the deeper aims of the Strategy and of English teaching, and that the constant assessment involved puts too much pressure on our youngsters at an age when they should be concentrating on social development as people.  相似文献   
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Special services usage and related assessment procedures were investigated for 50 students with epilepsy. Fifty‐six percent of students with epilepsy received special education services, with mental retardation designation and self‐contained placement common, especially among individuals with epilepsy plus a coexisting neurological diagnosis. Sixteen percent of participants had an “other health impairment” designation, and several of these were deemed eligible in at least one other special education category. The majority of students who had been evaluated were administered IQ, adaptive behavior, speech/language, and sensorimotor components, whereas few were assessed for executive or memory functions. Little information about antiepileptic drugs, their effects, or the actual manifestation of students' seizures appeared in special services school documents. Additional empirical information regarding services for children with chronic health conditions, such as epilepsy, is necessary to improve school psychologists' practice. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 169–181, 2006.  相似文献   
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This study is a comparative analysis of the characteristics of moral exemplars presented in moral education textbooks in Korea and Japan. The purpose of the study is to examine and compare moral values presented through the lives and stories of moral exemplars in the two countries that have moral education as an independent and separate subject based on the national curriculum. To this end, the study uses analytical criteria such as gender, nationality, social roles, historical backgrounds, and specific moral values in order to investigate characteristics of 307 moral exemplars in Korea’s and Japan’s most used moral education textbooks. The results show significant similarities and differences in moral exemplars between the two nations. In the case of the similarities, both countries emphasize moral autonomy and respect for human life. In the case of the differences, while Korea presents more historic figures as moral exemplars, Japan presents more students and ordinary people as moral exemplars.  相似文献   
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We elaborate a supply chain innovation matrix that can be applied to both commercial and military supply chains. By shifting the analysis from a focal firm to industry structure, we argue that the market structure of the entire supply chain functions as a major moderating variable in determining both the timing and adoption of innovations, both for commercial and military markets. We extend work on supply chain resource dependency by drawing a distinction between market-structure-induced resource dependency and supplier over-reliance on a customer in a competitive market. This has policy implications for the organization of military industrial research and development (IR&D). Joint service research and development (Jointness) will certainly bring about innovation, but it will be incremental, reinforcing established military hierarchies. Policy makers may need to add this probable consequence when comparing Jointness and inter-service rivalry. The cost savings inherent in Jointness may unwittingly sustain a military force unready for fighting the next war.  相似文献   
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