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951.

Science learning is inextricably tied to two aspects of students’ lives: literacy and culture. While English Learners (ELs) who speak a non-English native language are typically the focus in this line of scholarly inquiry, deaf and hard-of-hearing (DHH) students occupy a distinct space in this conversation. For DHH learners, literacy levels can be hindered by an early dependence on a more survival-based language learning model that postpones basic scientific inquiry. The vocabulary for curiosity is limited, which in turn affects the educational culture. DHH learners have a unique culture that demands an appropriate science curriculum, which thus far has not been explored or attempted for either DHH learners or their educators. Data collected consisted of interviews with teachers of DHH students, as well as observational data collected from a high-minority urban K-8 school for DHH students. The analysis revealed that, first, many of the teachers had limited preparation to teach science content. Second, DHH teachers used inconsistent instructional strategies ranging from drawing pictures to building models. Third, the modifications provided to DHH science learners were mostly limited to visual support and repetition. Implications for teacher education programs include instruction focused on specific supports for DHH students and co-teaching methods, and deeper investigation of inquiry-based science practices. Implications for classroom practices include providing hands-on, inquiry-based instruction, working closely with parents, and developing students’ and teachers’ understanding of scientific inquiry.

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952.
Science & Education - There is widespread agreement that an adequate understanding of the nature of science (NOS) is a critical component of scientific literacy and a major goal in science...  相似文献   
953.
This qualitative study was undertaken to explore what undergraduate students reflect on during their learning to practice social work in the field. Reflection is essential in the social work field practicum where students learn the practice of social work by doing. Seventeen BSW students’ final field practicum learning papers are analyzed. Four themes emerge that highlight the content of their reflections: situations of uncertainty, opportunities for application, tensions in action, and confrontations with others. This article presents in detail these 4 themes. Discussion includes suggestions for helping students better engage in reflective learning.  相似文献   
954.
This paper focuses on seven major managerial practices and three negative conditions that must be managed to enhance employee growth and development. These managerial practices and conditions have significant potential for human resource development practitioners and performance improvement technologists by providing new perspectives to improve employee performance through employee growth and development activities. Surveys measuring employee perceptions of manager behaviors were administered to 503 MBA and PhD students from the United States, resulting in 463 useable responses. The hypotheses were tested using linear regression and structural equation modeling. Based on the analysis, the researchers found that involving employees in decision making, motivating employees, treating employees as unique individuals, and making certain that managers are effective have the highest influence on employee growth and development.  相似文献   
955.
Abundant and diverse domestic mammals living on the Tibetan Plateau provide useful materials for investigating adaptive evolution and genetic convergence. Here, we used 327 genomes from horses, sheep, goats, cattle, pigs and dogs living at both high and low altitudes, including 73 genomes generated for this study, to disentangle the genetic mechanisms underlying local adaptation of domestic mammals. Although molecular convergence is comparatively rare at the DNA sequence level, we found convergent signature of positive selection at the gene level, particularly the EPAS1 gene in these Tibetan domestic mammals. We also reported a potential function in response to hypoxia for the gene C10orf67, which underwent positive selection in three of the domestic mammals. Our data provide an insight into adaptive evolution of high-altitude domestic mammals, and should facilitate the search for additional novel genes involved in the hypoxia response pathway.  相似文献   
956.
Complex oxides with tunable structures have many fascinating properties, though high-quality complex oxide epitaxy with precisely controlled composition is still out of reach. Here we have successfully developed solution-based single-crystalline epitaxy for multiferroic (1-x)BiTi(1-y)/2FeyMg(1-y)/2O3–(x)CaTiO3 (BTFM–CTO) solid solution in large area, confirming its ferroelectricity at the atomic scale with strong spontaneous polarization. Careful compositional tuning leads to a bulk magnetization of 0.07 ± 0.035 μB/Fe at room temperature, enabling magnetically induced polarization switching exhibiting a large magnetoelectric coefficient of 2.7–3.0 × 10−7 s/m. This work demonstrates the great potential of solution processing in large-scale complex oxide epitaxy and establishes novel room-temperature magnetoelectric coupling in epitaxial BTFM–CTO film, making it possible to explore a much wider space of composition, phase, and structure that can be easily scaled up for industrial applications.  相似文献   
957.
Living birds are unique among vertebrates in the formation of a female-specific bone tissue called medullary bone (MB) that is strictly associated with reproductive activity. MB is a rapidly mobilized source of calcium and phosphorus for the production of eggshell. Among living taxa, its skeletal distribution can be highly extensive such that it even exists in the ribs of some species. Due to its ephemeral nature, MB is rarely fossilized and so little is understood with regard to the origin of MB and its skeletal distribution in early taxa. Here we describe a new Early Cretaceous enantiornithine bird, Mirusavis parvus, gen. et. sp. nov., indicating that skeleton-wide distribution of MB appeared early in avian evolution. We suggest that this represents the plesiomorphic condition for the Aves and that the distribution of MB observed among extant neornithines is a product of increased pneumatization in this lineage and natural selection for more efficient distribution of MB.  相似文献   
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