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961.
Several cognitive psychologists have written about the importance of placing instruction within “authentic” contexts that mirror real-life situations. They argue that knowledge learned in academic settings does not necessarily transfer to non-academic settings. Whether preparing performance technologists or instructional designers, educators must strive to create meaningful problem-solving contexts that enable students to define, and subsequently solve, real-world problems. In an attempt to address this issue we have modified the way we teach instructional design. This paper discusses a cognitive apprenticeship approach to teaching design, which incorporates elements of modeling, coaching, reflection, articulation, and exploration. We describe how these features are embedded within three phases (orientation, situated training/learning, and exploration) of an introductory instructional design course designed to move our novice designers along a continuum of expertise as they develop and refine their own professional design skills. Although the apprenticeship model described here specifically addresses concerns within the context of preparing instructional designers, we believe that this model can be adapted to address similar issues in the education of performance technologists. 相似文献
962.
Obesity is a complex disease with multiple contributing factors.One of the most intensely studied factors during the past decade has been the gut microbiota,which is the community of all microbes in the intestinal tract.The gut microbiota,via energy extraction,inflammation,and other actions,is now recognized as an important player in the pathogenesis of obesity.Dysbiosis,or an imbalance in the microbial community,can initiate a cascade of metabolic disturbances in the host.Early life is a particularly important period for the development of the gut microbiota,and perturbations such as with antibiotic exposure can have long-lasting consequences for host health.In early life and throughout the life span,diet is one of the most important factors that shape the gut microbiota.Although diets high in fat and sugar have been shown to contribute to dysbiosis and disease,dietary fiber is recognized as an important fermentative fuel for the gut microbiota and results in the production of short-chain fatty acids that can act as signaling molecules in the host.One particular type of fiber,prebiotic fiber,contributes to changes in the gut microbiota,the most notable of which is an increase in the abundance of Bifidobacterium.This review highlights our current understanding of the role of gut microbiota in obesity development and the ways in which manipulating the microbiota through dietary means,specifically prebiotics,could contribute to improved health in the host,including musculo skeletal health. 相似文献
963.
Kelsey H.Collins Graham Z.MacDonald David A.Hart Ruth A.Seerattan Jaqueline L.Rios Raylene A.Reimer Walter Herzog 《运动与健康科学(英文)》2020,9(2):132-139,197
Background:Osteoarthritis is one of the leading causes of pain and disability worldwide,and a large percentage of patients with osteoarthritis are individuals who are also obese.In recent years,a series of animal models have demonstrated that obesity-inducing diets can result in synovial joint damage(both with and without the superimposition of trauma),which may be related to changes in percentage of body fat and a series of low-level systemic inflammatory mediators.Of note,there is a disparity between whether the dietary challenges commence at weaning,representing a weanling onset,or at skeletal maturity,representing an adult onset of obesity.We wished to evaluate the effect ofthe dietary exposure time and the age at which animals are exposed to a high-fat and high-sucrose(HFS) diet to determine whether these factors may result in disparate outcomes,as there is evidence suggesting that these factors result in differential metabolic disturbances.Based on dietary exposure time,we hypothesized that rats fed an HFS diet for 14 weeks from weaning(HFS Weanling) would demonstrate an increase in knee joint damage scores,whereas rats exposed to the HFS diet for 4 weeks,starting at 12 weeks of age(HFS Adult) and rats exposed to a standard chow diet(Chow)would not display an increase in knee joint damage scores.Methods:Male Sprague-Dawley rats were fed either an HFS diet for 14 weeks from weaning(HFS Weanling) or an HFS diet for 4 weeks,starting at 12 weeks of age(HFS Adult).At sacrifice,joints were scored using the modified Mankin Criteria,and serum was analyzed for a defined subset of inflammatory markers(Interleukin-6,leptin,monocyte chemoattractant protein-1,and tumor necrosis factorα).Results:When the HFS Weanling and HFS Adult groups were compared,both groups had a similar percent of body fat,although the HFS Weanling group had a significantly greater body mass than the HFS Adult group.The HFS Weanling and HFS Adult animals had a significant increase in body mass and percentage of body fat when compared to the Chow group.Although knee joint damage scores were low in all 3 groups,we found,contrary to our hypothesis,that the HFS Adult group had statistically significant greater knee joint damage scores than the Chow and HFS Weanling groups.Furthermore,we observed that the HFS Weanling group did not have significant differences in knee joint damage scores relative to the Chow group.Conclusion:These findings indicate that the HFS Weanling animals were better able to cope with the dietary challenge of an HFS diet than the HFS Adult group.Interestingly,when assessing various serum proinflammatory markers,no significant differences were detected between the HTS Adult and HFS Weanling groups.Although details regarding the mechanisms underlying an increase in knee joint damage scores in the HFS Adult group remain to be elucidated,these findings indicate that dietary exposure time maybe less important than the age at which an HFS diet is introduced.Moreover,increases in serum proinflammatory mediators do not appear to be directly linked to knee joint damage scores in the HFS Weanling group animals but may be partially responsible for the observed knee joint damage in the adults over the very short time of exposure to the HFS diet. 相似文献
964.
BackgroundHealth-related fitness knowledge (HRFK) has been an essential concept for many health and physical education programs. There has been limited understanding and longitudinal investigation on HRFK growth. This longitudinal study examined HRFK growth and its individual- and school-level correlates in middle school years under 1 curriculum condition: Five for Life.MethodsParticipants were 12,044 students from 47 middle schools. Data were collected at both individual/participant and school/institution levels. Individual-level variables included gender, grade, and HRFK test scores. School-level variables included percentage of students receiving free and reduced meals (FARM), student-to-faculty ratio for physical education, and school academic performance (SAP). We used hierarchical linear modeling to examine HRFK 3-year growth in relation to individual- and school-level correlates.ResultsThe average HRFK score at 6th grade for females was 42.81% ± 1.32%. The predicted HRFK growth was 17.06% ± 1.02% per year, holding other factors constant. A 1-standard deviation increase in FARM correlated with a 14.68%-point decrease in predicted test score (p = 0.02). A 1-standard deviation increase in SAP was associated with an 11.90%-point increase in HRFK score. Males had a significantly lower growth rate than females during the middle school years (0.78%/year, p = 0.02).ConclusionThe result showed that both individual- and school-level variables such as gender, FARM, and SAP influenced HRFK growth. Educators should heed gender differences in growth curves and recognize the correlates of school-level variables. 相似文献
965.
为推动我国校园足球的发展,丰富校园足球发展理论,对我国小学一年级至大学四年级全日制在校师生,及与之对应的学生家长和所在地区的教育主管部门等进行了调查研究,借助于系统动力学理论,构建校园足球发展系统动力学模型,并利用实际调查数据对模型进行了仿真。结果表明:我国校园足球总体发展动力不强:就系统内环境而言,学生的足球运动需要、可支配运动时间、场地器材及师资力量等系统要素发展不协调,阻碍了校园足球发展;就系统外环境而言,足球的教育价值宣传力度较小、特长生升学通道不畅、足球专项资金监管力度较低等因素,影响校园足球内环境要素的发展,进而影响校园足球的发展。为促进校园足球发展,国家需要大力宣传足球运动的教育价值,完善足球特长生升学通道,加强场地器材建设和师资培训,强化校园足球专项资金的监管力度。 相似文献
966.
This paper reports results from a study exploring the multimedia search functionality of Chinese language search engines. Web searching in Chinese (Mandarin) is a growing research area and a technical challenge for popular commercial Web search engines. Few studies have been conducted on Chinese language search engines. We investigate two research questions: which Chinese language search engines provide multimedia searching, and what multimedia search functionalities are available in Chinese language Web search engines. Specifically, we examine each Web search engine’s (1) features permitting Chinese language multimedia searches, (2) extent of search personalization and user control of multimedia search variables, and (3) the relationships between Web search engines and their features in the Chinese context. Key findings show that Chinese language Web search engines offer limited multimedia search functionality, and general search engines provide a wider range of features than specialized multimedia search engines. Study results have implications for Chinese Web users, Website designers and Web search engine developers. 相似文献
967.
968.
IPv4, the workhorse protocol of the currently popular TCP/ IP protocol suite, is fast becoming obsolete. The exponential growth
of the Internet is the main reason that has required the creation of the next generation of Internet Protocol-IPv6. IPv6 is
much more flexible and promises to take care of the address space and security issues in the foreseeable future.
Part 1 of the paper lays the foundation of the various issues involved in designing the Internet Protocol and motivates the
need for an upgraded version of this protocol. 相似文献
969.
Campbell AM Zanta CA Heyer LJ Kittinger B Gabric KM Adler L Schulz B 《CBE life sciences education》2006,5(4):332-339
We have developed a wet lab DNA microarray simulation as part of a complete DNA microarray module for high school students. The wet lab simulation has been field tested with high school students in Illinois and Maryland as well as in workshops with high school teachers from across the nation. Instead of using DNA, our simulation is based on pH indicators, which offer many ideal teaching characteristics. The simulation requires no specialized equipment, is very inexpensive, is very reliable, and takes very little preparation time. Student and teacher assessment data indicate the simulation is popular with both groups, and students show significant learning gains. We include many resources with this publication, including all prelab introductory materials (e.g., a paper microarray activity), the student handouts, teachers notes, and pre- and postassessment tools. We did not test the simulation on other student populations, but based on teacher feedback, the simulation also may fit well in community college and in introductory and nonmajors' college biology curricula. 相似文献
970.
Youth on the street: Abuse and neglect in the eighties 总被引:2,自引:0,他引:2
This paper discusses the findings of a study of runaways and homeless youth who were interviewed on the street the last week of every month on five week nights from late afternoon until 2 a.m. over a period of one year. The data derived from 489 interviews provided some interesting insights. Two distinct groups emerged from the analysis, generating a tentative hypothesis that the true "runners" tend to leave their homes with the intention of not returning and thus their runs are extended; the second group, designated "in and outers," use the run as a temporary coping mechanism. Their runs tend to be impulsive and of short duration. The study found that runaways (in particular the runners) are at great risk of being drawn into illegal activities. Major factors affecting this risk are distance from home and length of time on the run. A significant proportion of the youth interviewed had run from substitute care arrangements, and a disturbing implication emerging from the research is that adolescents in our society suffer from systemic abuse and neglect. One outcome of this piece of research was the opening of a safe house for early runners in January 1987. The operation of the house includes careful compilation of data to further advance understanding of the runaway population and its needs. 相似文献