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51.
Eun-hye Park Won-young Bae Jae-yeon Kim Kee-tae Kim Hyun-dong Paik 《Journal of Zhejiang University. Science. B》2017,18(9):816-824
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
52.
Pedagogical Agents as Learning Companions: The Role of Agent Competency and Type of Interaction 总被引:1,自引:0,他引:1
Yanghee Kim Amy L. Baylor 《Educational technology research and development : ETR & D》2006,54(3):223-243
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
53.
An efficient method for tracing planar implicit curves 总被引:1,自引:0,他引:1
YU Zheng-sheng CAI Yao-zhi OH Min-jae KIM Tae-wan PENG Qun-sheng 《浙江大学学报(A卷英文版)》2006,7(7):1115-1123
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
54.
ABSTRACTResearch Findings: Continuity of care is a recommended practice in child care intended to promote secure and supportive relationships between infants and toddlers and their caregivers. Toddlers (N = 115) between 12 and 24 months were observed in 30 continuity and 29 noncontinuity classrooms. The average duration of care for toddlers with caregivers was 14 months in the continuity rooms and 5 months in noncontinuity rooms. Toddlers observed in continuity rooms experienced higher levels of interactive involvement with their caregivers and were rated by their caregivers as having fewer problem behaviors compared with the toddlers in noncontinuity rooms. Toddlers in rooms with higher staff–child ratios also experienced more involved caregiving. We did not find evidence that the level of involved caregiving mediated the association between continuity of care and toddlers’ social competence or problem behaviors. Practice or Policy: Continuity of care may be a promising practice for programs that strive to provide high-quality care for infants and toddlers. 相似文献
55.
A large urban school district contracted with a private nonprofit educational foundation to train 126 special education resource
teachers in the last three years in an Orton-Gillingham-based program. These teachers are currently teaching learning-disabled
students in groups of 8–10 at the elementary level and 10–13 students at the secondary level. Learning-disabled students who
qualify for Special Education, either in reading or spelling, or both, are receiving the instruction.
The teachers took a Basic Introductory Class (90 hours of Advanced Academic Credit offered by the Texas Education Agency,
or six hours of graduate credit at a local university) in order to teach the program in the resource setting. A two year Advanced
Training included annual on-site observations, two half-day workshops each fall and spring, and a two-day advanced workshop
in the second summer.
First grade teachers, one selected from each of the 164 campuses, supervisors, and principals attended a 25-hour course on
“Recognizing Dyslexia: Using Multisensory Teaching and Discovery Techniques.” The first grade teachers and special education
resource teachers collaborated to provide inservice training for their colleagues.
Research, conducted by the district’s Research Department, reveals statistically significant gains in reading and spelling
ability for the learning-disabled resource students as measured by the Woodcock Reading Mastery Test-Revised, and the Test
of Written Spelling. 相似文献
56.
A quantitative analysis of moral exemplars presented in moral education textbooks in Korea and Japan
Hyemin Han Sung Choon Park Jongsung Kim Changwoo Jeong Yutaka Kunii Sora Kim 《Asia Pacific Journal of Education》2018,38(1):62-77
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
57.
This paper examines the factors affecting the performance of global query expansion based on term co-occurrence data and suggests a way to maximize the retrieval effectiveness. Major parameters to be optimized through experiments are term similarity measure and the weighting scheme of additional terms. The evaluation of four similarity measures tested in query expansion reveal that mutual information and Yule's Y, which emphasize low frequency terms, achieve better performance than cosine and Jaccard coefficients that have the reverse tendency. In the evaluation of three weighting schemes, similarity weight performs well only with short queries, whereas fixed weights of approximately 0.5 and similarity rank weights were effective with queries of any length. Furthermore, the optimal similarity rank weight achieving the best overall performance seems to be the least affected by test collections and the number of additional terms. For the efficiency of retrieval, the number of additional terms needs not exceed 70 in our test collections, but the optimal number may vary according to the characteristics of the similarity measure employed. 相似文献
58.
59.
Three aspects of the most important problem questionused in agenda-setting research to measure issue salience amongthe public were examined. A split-ballot design in a state-widesurvey compared versions of the public agenda with a socialframe of reference versus a personal frame of reference, versionsusing the traditional term problem versus issue,and the effects of question order. High correlations betweenthe different versions were found in all three sets of comparisons. 相似文献
60.
The purpose of this study is to examine the relationship between perceived ageism and depression in later life and to clarify the mechanism underlying this relationship by examining the mediating effects of self-perception of aging and purpose in life. The Health and Retirement Study surveys were used for this secondary analysis of data. The sample included 3,991 older adults, and structural equation modeling (SEM) analyses using structural regression models were conducted. SEM analyses revealed that full mediation effects of self-perception of aging and purpose in life exist. Older adults who perceive ageism are likely to have negative self-perception of aging, and this negative view of their own aging is likely to decrease purpose in life and increase depressive symptoms. The results of this study imply that more efforts and resources are necessary to reduce ageism and its negative effect on depression among older adults. Additionally, the current study suggests the necessity of anti-ageism policies and social services. Increasing positive self-perception of aging, purpose in life, and resilience could be the key to a better quality of life for older adults. 相似文献