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141.
A protocol of polymerase chain reaction-random amplified polymorphic DNAs (PCR-RAPDs) was established to analyse the gene diversity and genotype identification for clones of Sequoia sempervirens (D. Don) Endl. in Chile. Ten (out of 34) clones from introduction trial located in Voipir-Villarrica, Chile, were studied. The PCR-RAPDs technique and a modified hexadecyltrimethylammonium bromide (CTAB) protocol were used for genomic DNA extraction. The PCR tests were carried out employing 10-mer random primers. The amplification products were detected by electrophoresis in agarose gels. Forty nine polymorphic bands were obtained with the selected primers (BG04, BF07, BF12, BF13, and BF14) and were ordered according to their molecular size. The genetic similarity between samples was calculated by the Jaccard index and a dendrogram was constructed using a cluster analysis of unweighted pair group method using arithmetic averages (UPGMA). Of the primers tested, 5 (out of 60) RAPD primers were selected for their reproducibility and high polymorphism. A total of 49 polymorphic RAPD bands were detected out of 252 bands. The genetic similarity analysis demonstrates an extensive genetic variability between the tested clones and the dendrogram depicts the genetic relationships among the clones, suggesting a geographic relationship. The results indicate that the RAPD markers permitted the identification of the assayed clones, although they are derived from the same geographic origin. Project (No. CONICYT-FONDEF PROYECT D01 I 1008) supported by the National Commission of Science and Research of Chile  相似文献   
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All too often, strong opinions are held without regard to detailed knowledge of the subject involved. Current controversies show that the question of course content in professional broadcasting education is no exception. Regardless of the viewpoint held, a supply of adequate data relevant to the question should be welcomed by all. The Journal undertakes to supply as much data as possible relevant to broadcasting education, the most recent example being Harold Niven's “Fourth Annual Survey of Colleges and Universities Offering Course Work in Radio and Television, 1958–1959”; published in the Fallissue.  相似文献   
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This study is designed to identify the underlying satisfaction dimensions gained through engagement in target shooting as a serious leisure pastime. The instrument design was based on the Leisure Satisfaction Scale. A total of 5502 useable surveys were collected through the Internet and a website related to target shooting and gun ownership. The results revealed eight dimensions: self-actualization, social interaction, location aesthetic, respite, physical benefit, connection and hedonic pleasure, which supplied the primary satisfiers of engaging in target shooting as a serious leisure activity. The demographic profile and dimensions of satisfaction may serve to dispel commonly held stereotypes of shooting hobbyists and those involved in gun ownership. The findings have important implications for leisure researchers and practitioners, to industry, both leisure and firearm related, and the target shooting community at large. This study adds to the literature of both target shooting and serious leisure.  相似文献   
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Recent years have witnessed a noticeable proliferation in Digital Library Systems (DLSs) and their specialized form represented in Digital Heritage Resources (DHRs). DHRs usually manage a complex and varied mix of digital heritage objects of different types and formats. They tend to be complex in nature and usually involve complex, simultaneous and intersecting workflows. As a result, DHRs impose implementation challenges on any solutions that aim to manage their workflows. Thus, despite the proliferation of DHRs, it is a noteworthy trend that there is a general lack of workflow management solutions that can be utilized in such systems. As a research area that is rarely covered, this paper therefore presents the design and development of a novel Workflow Management System (WfMS) built to integrate with DHRs specifically, and DLSs in general. In this context, an experimental WfMS aimed to test the validity of workflow management integration with DHRs. The devised WfMS was built as a workflow management solution that can adequately address the specific hurdles imposed by DHR implementations. Additionally, a novel DHR implementation framework called DISPLAYS (Digital Library Services for Playing with Antiquity and Shared Heritage) is presented as a test bed for the proposed WfMS.  相似文献   
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The paper makes a connection between transmission modes and constructivism in sociology and education, respectively. There are parallels between Archer’s criticism of upward and downward conflation in social theory, and approaches to learning in education. In her 2012 book, Archer seeks to reconceptualise socialisation as relational reflexivity. This paper seeks to connect this idea to thinking about learning in relational terms and links the analysis to Young’s account of ‘bringing knowledge back in’. The paper uses an example from field work on participation in learning to provide concrete examples that illuminate the points being made. It argues that learning theory needs to move away from transmission and the constructivists’ ideas about education and to consider the relational aspects of learning.  相似文献   
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The aims of this study were to describe normative values and seasonal variation of body composition in female cyclists comparing female road and track endurance cyclists, and to validate the use of anthropometry to monitor lean mass changes. Anthropometric profiles (seven site skinfolds) were measured over 16 years from 126 female cyclists. Lean mass index (LMI) was calculated as body weight?×?skinfolds?x. The exponent (x) was calculated as the slope of the natural logarithm of body weight and skinfolds. Percentage changes in LMI were compared to lean mass changes measured using dual-energy X-ray absorptiometry (DXA) in a subset of 25 road cyclists. Compared to sub-elite and elite cyclists, world class cyclists were (mean [95% CI]) 1.18?kg [0.46, 1.90] and 0.60?kg [0.05, 1.15] lighter and had skinfolds that were 7.4?mm [3.8, 11.0] and 4.6?mm [1.8, 7.4] lower, respectively. Body weight (0.41?kg [0.04, 0.77]) and skinfolds (4.0?mm [2.1, 6.0]) were higher in the off-season compared to the early-season. World class female road cyclists had lower body weight (6.04?kg [2.73, 9.35]) and skinfolds (11.5?mm [1.1, 21.9]) than track endurance cyclists. LMI (mean exponent 0.15 [0.13, 0.18]) explained 87% of the variance in DXA lean mass. In conclusion, higher performing female cyclists were lighter and leaner than their less successful peers, road cyclists were lighter and leaner than track endurance cyclists, and weight and skinfolds were lowest early in the season. LMI appears to be a reasonably valid tool for monitoring lean mass changes.  相似文献   
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