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131.
Herein is described the fabrication and use of a plastic multilayer 3-channel microfluidic fixture. Multilayer devices were produced by laser machining of plastic polymethylmethacrylate and polyethyleneterapthalate laminates by ablation. The fixture consisted of an array of nine individually addressable gold or gold/ITO working electrodes, and a resistive platinum heating element. Laser machining of both the fluidic pathways in the plastic laminates, and the stencil masks used for thermal evaporation to form electrode regions on the plastic laminates, enabled rapid and inexpensive implementation of design changes. Electrochemiluminescence reactions in the fixture were achieved and monitored through ITO electrodes. Electroaddressable aryl diazonium chemistry was employed to selectively pattern gold electrodes for electrochemical multianalyte DNA detection from double stranded DNA (dsDNA) samples. Electrochemical detection of dsDNA was achieved by melting of dsDNA molecules in solution with the integrated heater, allowing detection of DNA sequences specific to breast and colorectal cancers with a non-specific binding control. Following detection, the array surface could be renewed via high temperature (95 °C) stripping using the integrated heating element. This versatile and simple method for prototyping devices shows potential for further development of highly integrated, multi-functional bioanalytical devices.  相似文献   
132.
In this study, carbon fiber electrodes were incorporated within a hollow microneedle array, which was fabricated using a digital micromirror device-based stereolithography instrument. Cell proliferation on the acrylate-based polymer used in microneedle fabrication was examined with human dermal fibroblasts and neonatal human epidermal keratinocytes. Studies involving full-thickness cadaveric porcine skin and trypan blue dye demonstrated that the hollow microneedles remained intact after puncturing the outermost layer of cadaveric porcine skin. The carbon fibers underwent chemical modification in order to enable detection of hydrogen peroxide and ascorbic acid; electrochemical measurements were demonstrated using integrated electrode-hollow microneedle devices.  相似文献   
133.
Combining home–school literacy bags with preschool family literature circles provided a strong foundation for family involvement at home and school during this year-long Reading Partners project, and helped parents become essential partners in their children’s literacy development. Using home–school literacy bags, children and parents learned how to combine expressive arts and emergent literacy strategies including alphabet recognition, phonemic and phonological awareness, and oral language fluency. State-of-the-art activities designed for each of the multiple intelligences met the needs of diverse students with many different learning styles and interests. As families participated in fall and spring school-based Festivals in which they shared the literacy bags in small group family literature circles, they demonstrated children’s emerging literacy skills in a relaxed, yet highly engaging atmosphere.  相似文献   
134.
Research Findings: In an effort toward developing a comprehensive, effective, scalable, and sustainable early childhood education program for at-risk populations, we conducted an experimental evaluation of the value added by 2 family involvement programs to the Texas Early Education Model (TEEM). A total of 91 preschool classrooms that served minority populations of low socioeconomic status were randomly assigned to TEEM, TEEM plus Raising a Reader (RAR), or TEEM plus RAR augmented by Family Nights. Assessments of oral language and print knowledge were completed by more than 500 children at the beginning and end of the school year. Multilevel analyses of covariance controlled for classroom nesting and individual differences in age, ethnicity, and pretest scores. Although RAR alone demonstrated no added value, augmentation of RAR with Family Nights demonstrated significant impacts on measures of oral language (ts = 1.81–2.51, .05 < ps < .01) and print knowledge (t = 2.39, p < .01). Practice or Policy: Thus, parent training in shared reading practices appears to be necessary for children to benefit from programs that enrich the home literacy environment. That the combined program particularly benefited children who started preschool lagging behind in school readiness (ts = 1.64–2.49, ps < .05) suggests that this comprehensive model offers hope for closing the achievement gap.  相似文献   
135.
Research Findings: Children's early academic achievement is supported by positive social and behavioral skills, and difficulties with these skills frequently gives way to underachievement. Social and behavioral problems often arise as a product of parent–child interactional patterns and environmental influences. Few studies have examined the role of a salient aspect of children's environments, community locale, in the relationship between parenting practices and child outcomes. Using a large, nationally representative sample, we examined whether preschool parenting practices and children's social-behavioral skills in kindergarten were related to geographic setting (rural vs. city, suburban, and town). Results indicated that rural children experienced greater difficulties with parent-reported externalizing behaviors. Furthermore, rural parents displayed less emotional support than parents in other settings. Preschool parenting behaviors were associated with social skills and behavior problems in kindergarten, as reported by both parents and teachers. Parents' emotional supportiveness was found to account for the relationship between geographic setting and parent-reported children's social skills, such that rural parents who provided less emotional support had children with lower social skills in kindergarten. Practice or Policy: Findings of this research indicate that rural children may face particular risk for behavioral issues and highlight the need for increased behavioral supports in rural communities. Moreover, our results suggest that interventions designed to promote parents' support of children's emotions may have particular utility for rural families.  相似文献   
136.
137.
Societal response to climate change has been inadequate. A perception that the issue is both physically and temporally remote may reduce concern; concern may also be affected by the political polarization surrounding the issue in the USA. A feeling of connection to nature or to animals may increase personal relevance, and a supportive social context may counteract political tensions. Zoos may provide opportunities for both sense of connection and social support. We surveyed over 7000 zoo and aquarium visitors to examine the ways in which a feeling of personal connection among zoo visitors may encourage concern about climate change. Results show that feeling connected to animals at the zoo is significantly associated with cognitive and emotional responses to climate change, as well as with other social groupings and social responses. Overall, the zoo seems to present a supportive social context for considering the topic.  相似文献   
138.
This article highlights the practices of administrators and master teachers who are trying to balance the needs for accountability, prescribed curriculum, and learning standards with a broader view of education that gives equal importance to skills not so easily quantified by standardized tests. The author makes a case for the use of careful observation of children, and documentation and analysis of project-based activities as a way to create a more complete picture of a child's skills while at the same time, supporting the innate desire to learn with which all children start life.  相似文献   
139.
Online plagiarism tutorials are increasingly popular in higher education, as faculty and staff try to curb the plagiarism epidemic. Yet no research has validated the efficacy of such tools in minimizing plagiarism in the sciences. Our study compared three plagiarism-avoidance training regimens (i.e., no training, online tutorial, or homework assignment) and their impacts on students’ ability to accurately discriminate plagiarism from text that is properly quoted, paraphrased, and attributed. Using pre- and postsurveys of 173 undergraduate students in three general ecology courses, we found that students given the homework assignment had far greater success in identifying plagiarism or the lack thereof compared with students given no training. In general, students trained with the homework assignment more successfully identified plagiarism than did students trained with the online tutorial. We also found that the summative assessment associated with the plagiarism-avoidance training formats (i.e., homework grade and online tutorial assessment score) did not correlate with student improvement on surveys through time.  相似文献   
140.
Susan 《新高考》2014,(12):31-31
A Spanish soldier has battled his way to the top of the beauty charts having been crowned Mr Universe. But Ruben Lopez vowed not to let the title of hottest man in the world go to his head, instead intending to stand by his troops and stay in military.  相似文献   
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