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111.
Spatial resolution defines the physical limit of microscopes for probing biomolecular localization and interactions in cells. Whereas synchrotron-based X-ray microscopy (XRM) represents a unique approach for imaging a whole cell with nanoscale resolution due to its intrinsic nanoscale resolution and great penetration ability, existing approaches to label biomolecules rely on the use of exogenous tags that are multi-step and error-prone. Here, we repurpose engineered peroxidases as genetically encoded X-ray-sensitive tags (GXET) for site-specific labeling of protein-of-interest in mammalian cells. We find that 3,3-diaminobenzidine (DAB) polymers that are in-situ catalytically formed by fusion-expressed peroxidases are visible under XRM. Using this new tag, we imaged the protein location associated with the alteration of a DNA-methylation pathway with an ultra-high resolution of 30 nanometers. Importantly, the excellent energy resolution of XRM enables multicolor imaging using different peroxidase tags. The development of GXET enlightens the way to nanoscopic imaging for biological studies.  相似文献   
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113.
This study investigates how scaffolding type and learners’ epistemological beliefs influence ill-structured problem solving. The independent variables in this study include the type of scaffolding (task-supported, self-monitoring) and the student's epistemological belief level (more advanced, less advanced). The dependent variables include three components of problem-solving skill (problem representation, solution development, monitoring and evaluation). The two-way multivariate analysis of variance results reveal that students in the self-monitoring scaffolding group earned higher scores on problem representation and solution development than those in the task-supported scaffolding group. Students with more advanced epistemological beliefs also earned higher scores on solution development and monitoring and evaluation than did those with less advanced epistemological beliefs. In addition, a significant interaction was found between scaffolding type and epistemological belief level. These findings suggest that students can benefit from self-monitoring scaffolding in web-based problem solving and that different types of scaffolding should be provided according to the student's epistemological belief level.  相似文献   
114.
This study examines how the neighborhood storytelling network, which is conceptualized in communication infrastructure theory and includes interpersonal, organizational and community media connectedness, and an individual's Internet connectedness affected participation in civic activities in the aftermath of the Great East Japan Earthquake, which occurred on 11 March 2011. Responses from 544 randomly selected people residing in Tokyo reveal that connectedness to a neighborhood storytelling network and one's Internet connectedness have positive effects on participation in civic activities in response to the earthquake. However, the two independent factors (neighborhood storytelling and Internet connectedness) do not exhibit a significant relationship with each other. The result suggests the existence of two different conduits for civic engagement in disaster situations – neighborhood storytelling networks and Internet connectedness – mainly distinguished by age.  相似文献   
115.
Big data analytics associated with database searching, mining, and analysis can be seen as an innovative IT capability that can improve firm performance. Even though some leading companies are actively adopting big data analytics to strengthen market competition and to open up new business opportunities, many firms are still in the early stage of the adoption curve due to lack of understanding of and experience with big data. Hence, it is interesting and timely to understand issues relevant to big data adoption. In this study, a research model is proposed to explain the acquisition intention of big data analytics mainly from the theoretical perspectives of data quality management and data usage experience. Our empirical investigation reveals that a firm's intention for big data analytics can be positively affected by its competence in maintaining the quality of corporate data. Moreover, a firm's favorable experience (i.e., benefit perceptions) in utilizing external source data could encourage future acquisition of big data analytics. Surprisingly, a firm's favorable experience (i.e., benefit perceptions) in utilizing internal source data could hamper its adoption intention for big data analytics.  相似文献   
116.
Beyond Interaction: The relational construct of 'Transactional Presence'   总被引:1,自引:0,他引:1  
Namin Shin 《Open Learning》2013,28(2):121-137
This paper presents the novel construct of 'Transactional Presence' in consideration of a distance student's perceptions of psychological presence on the part of teachers, peers, and institutions. Relevant distance education literature is analyzed through the lens of interpersonal relationships, and concepts such as telepresence and social presence are drawn from media and communication studies. When the two streams of literature reviewed are merged, it is conjectured that the perception of presence concerned must be influenced by distance students' idiosyncratic needs for connection with learning resources and sources of support. This notion of presence, designated 'Transactional Presence', is defined as the degree to which a distance student perceives the availability of, and connectedness with, other parties involved in a given distance education setting. The construct's potential significance is explored in view of enriching distance education theory and research.  相似文献   
117.

In the present study, we describe a participating student’s (Carol’s) distributive partitioning scheme and operations along with Steffe’s and his colleagues’ studies about children’s constructions of fraction knowledge as a particular model of mathematical learning. Analysis of Carol’s mathematical behaviors indicates that an operationally common mathematical behavior (distributive partitioning operation) was revealed in various mathematical problem situations such as fraction multiplication, fraction division, and multiplicative transformation between fractional quantities. It both provides a rationale for why becoming versed in one mathematical subject could facilitate working with another mathematical subject and also implies the necessity of describing and defining students’ mathematical behaviors from an operational view of knowledge, which might lead to building foundations of a substantial cognitive map for students’ mathematical development.

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118.
We re-conceptualized the meaning of scientific literacy and developed an instrument, which we call the Global Scientific Literacy Questionnaire (GSLQ) based on a new conceptual framework for scientific literacy in the twenty-first century. We identified five dimensions, each with key elements. The five dimensions are (1) content knowledge (core ideas of science), (2) habits of mind (science practices), (3) character and values, (4) science as human endeavor, and (5) metacognition and self-direction. In this study, we attempted to diagnose the extent to which South Korean secondary students perceive themselves as global citizens having such capabilities using GSLQ with 3,202 students (7th–12th grades). Validity and reliability were examined using various statistical techniques including the Cronbach's α coefficient, exploratory factor analysis, and confirmatory factor analysis. The use and value of the instrument were discussed by examining the Korean secondary students’ overall scientific literacy as well as their views on each dimension across gender and grade levels. We recommend that teachers and researchers use the GSLQ to assess students’ global scientific literacy and provide comments on its usefulness as a research tool and the practical use of its inventory of items.  相似文献   
119.
Many efforts have been made to reach educational equity, especially to reduce mathematics and science achievement gaps by students’ socioeconomic status. Across countries, educators strive to reform traditional teacher-centered instructional approaches to more student-centered/inquiry-based instruction to improve equity in education. In this context, this study examines whether relationships between socioeconomic status and scientific or mathematical literacy are moderated by student-centered instruction. Ten countries covering a wide range of achievement levels as well as equity in education are selected for an international comparison. A linear regression analysis is applied to student achievement, equity, and frequency of student-centered instruction data from the PISA 2012 and PISA 2015. We find mixed results: As student-centered instruction is offered more frequently, the gap in mathematical and scientific literacy between low and high socioeconomic status is generally narrowed or maintained. In most countries, students’ mathematical and scientific literacy scores are expected to decrease across all socioeconomic status as student-centered instruction is given more frequently. The findings necessitate further scrutiny of how teachers implement student-centered instruction in various educational systems. This further research need to consider the complexity of implementation related to sociological and pedagogical aspects.  相似文献   
120.
While sport management scholars have explored inter-organizational partnerships and their associated challenges, they have devoted less attention to inter-organizational partnership development and sustainability in sport for development and peace (SDP), particularly across a wide range of organizations with varied missions and foci. Hence, the purpose of this qualitative study was to examine challenges faced by SDP organizations when forming and sustaining inter-organizational partnerships across contexts and partnership types, and to uncover strategies they have employed to overcome these challenges. Common challenges encountered across 29 SDP organizations included competition for resources, skepticism of sport as a development tool, unequal power relations, misaligned goals and mission drift, and implementation issues. Strategies included focusing on building relationships and networks, demonstrating benefits to partner, starting small then diversifying, keeping focused on mission and goals, involving partner, and treating the partnership as a business relationship. Theoretical extensions and practical implications are discussed, along with directions for future research.  相似文献   
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