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Most traditional concepts about creative writers include the idea that creative talent is evident early - that productive and talented writers began their careers at a young age. Yet few empirical studies have actually examined this supposition. A study of 986 creative writers from the twentieth century investigated the relationship between the age at first publication and measures of productivity (numbers of works produced) and success (winning a Nobel or Pulitzer prize). While significant relationships were found between an early debut and increased productivity in poetry and total number of works, it is more noteworthy that a writer's age at first publication was not significantly related to total productivity in fiction or success. Implications for creative writers and teachers of creative writing are discussed, along with how these findings might be incorporated into the current standards-based reform efforts.  相似文献   
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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   
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The need of inspecting a masterpiece of fine art without affecting it led to develop non destructive methods of investigation. In the field of art conservation, several diagnostic techniques are being widely used to inspect works of art, giving different but complementary results. The present work deals with two of these methods, reflectography and thermography, both techniques examining objects in the infrared spectrum but in different wavelength bands. Their integrated data potentially provide a powerful tool for mapping hidden features and alterations of artworks. This was confirmed during the inspections of a 13th century panel painting under restoration at the Opificio delle Pietre Dure laboratories (Florence, Italy). A graphical user interface was also designed to aid operators in the field of conservation dealing with the results of the two IR methods. Many options such as image adjustment, comparison, overlaying and transparency variation, in addition to thermographic elaborations, have been made available to users. Imaging data integration provides a multi-layered and multi-spectral representation of the painting that yields a comprehensive diagnosis confirms the anomalies individuation and reduces the ambiguities of information coming from a single diagnostic method.  相似文献   
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This article addresses the issue of transition from secondary to post-secondary education through collaborative research with teachers from both levels. It takes into account implicit elements in this transition. Research on the transition in mathematics education tends to focus more on the tertiary level, studying difficulties encountered by students or comparing curricula, tasks, and textbooks highlighting disruptions or cultural shifts. However, according to Hall (1959), and Artigue (2004) in a mathematical context, it is the implicit “ways of doing” that lead to the greatest cultural differences. In this article, attention is paid to the particular ways in which teachers’ ways of doing mathematics impact the transition. Ethnomethodology (Garfinkel, 1967) and its central concept of ethnomethods are used as the theoretical framework to conceptualize these ways of doing mathematics. A breaching situation presented to a group of secondary- and tertiary-level teachers engaged in collaborative research (Desgagné et al., 2001) brings to light familiar ways of doing mathematics. Our analysis focuses specifically on a comparison of the ways of doing mathematics related to functions at each level.  相似文献   
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Online higher education institutions are presented with the concern of how to obtain valid results when administering student learning outcomes (SLO) assessments remotely. Traditionally, there has been a great reliance on unproctored Internet test administration (UIT) due to increased flexibility and reduced costs; however, a number of validity concerns have led some researchers to question its implementation and results. To mitigate the limitations of UIT, a relatively new approach, referred to as online proctoring, has been developed to mirror in-person proctoring remotely by capitalizing on technology to create verifiable and secure testing conditions. This study evaluated the comparability of online proctored and unproctored test administration in a low-stakes testing context on user-friendliness, examinee behavior, and mean scores. Results demonstrated improved user-friendliness (e.g., ease of logging in); however, no significant differences were observed in terms of keystroke information, rapid guessing, or aggregated scores between proctoring conditions. Overall, these results suggest that online institutions can implement UIT, which is a cost-effective approach to test administration, and obtain valid group-level inferences from SLO assessments.  相似文献   
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The World Health Organization Regional Office for Europe (WHO EURO) and the German Federal Centre for Health Education (BZgA) published the Standards for Sexuality Education in Europe in 2010. The standards were developed to provide an overview of those sexuality education issues that should be addressed in school at various specific age levels. They were intended to guarantee that sexuality education teaching is age-appropriate and of uniformly good quality throughout Europe. In the context of the present survey, Austrian teachers and parents or guardians were asked about the importance of the topics covered by the WHO standards and about any aspects they would like to see for such sexuality education to be successful. The paper concludes that parents and teachers agree on the sexuality education topics they find important for coverage in Austrian primary schools, although teachers find sexuality education in general to be of greater importance than do parents. Teacher’ wishes for sexuality education in practice correlate highly with parents’ ideas of quality. Overall, qualifications and support for work in this field are viewed as essential, with survey respondents perceiving the need for high-quality initial training and continuing education and appropriate frameworks for implementation in school.  相似文献   
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As low-stakes testing contexts increase, low test-taking effort may serve as a serious validity threat. One common solution to this problem is to identify noneffortful responses and treat them as missing during parameter estimation via the effort-moderated item response theory (EM-IRT) model. Although this model has been shown to outperform traditional IRT models (e.g., two-parameter logistic [2PL]) in parameter estimation under simulated conditions, prior research has failed to examine its performance under violations to the model’s assumptions. Therefore, the objective of this simulation study was to examine item and mean ability parameter recovery when violating the assumptions that noneffortful responding occurs randomly (Assumption 1) and is unrelated to the underlying ability of examinees (Assumption 2). Results demonstrated that, across conditions, the EM-IRT model provided robust item parameter estimates to violations of Assumption 1. However, bias values greater than 0.20 SDs were observed for the EM-IRT model when violating Assumption 2; nonetheless, these values were still lower than the 2PL model. In terms of mean ability estimates, model results indicated equal performance between the EM-IRT and 2PL models across conditions. Across both models, mean ability estimates were found to be biased by more than 0.25 SDs when violating Assumption 2. However, our accompanying empirical study suggested that this biasing occurred under extreme conditions that may not be present in some operational settings. Overall, these results suggest that the EM-IRT model provides superior item and equal mean ability parameter estimates in the presence of model violations under realistic conditions when compared with the 2PL model.  相似文献   
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This paper investigates whether a green kind of design helps firms increase their capabilities for inventing in the environmental domain and whether it does so more than ‘standard’ design. It also investigates whether the effect of ‘green-matching’ between new design and technologies is conditional on firms’ innovative capabilities, as reflected by their R&D expenditure. We address these research questions with respect to the world's top R&D investors, looking at their intellectual property rights at the United States Patent and Trademark Office (USPTO) and proposing an original textual identification of green designs and trademarks. We find that green design increases environmental inventions by top R&D investors, and to a greater extent than non-environmental ones. Standard design also stimulates environmental inventions, but to a lesser extent than green design. The ‘green-matching’ actually helps, but internal innovative capabilities are required to make it effective: a green-tech ‘prize’ emerges from green design, but only once a minimum threshold of R&D expenditure has been reached.  相似文献   
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