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Although many environmental and science educators have explored students’ conceptual understandings, misconceptions, and knowledge of the greenhouse effect, global warming, and climate change, few have investigated the ways students conceptualize climate as a system or how components of the system influence climate. Therefore, the purpose of this study was to begin the process of understanding how US students conceptualize a climate system. A total of 42 seventh grade students (ages 12–13) from the Midwest completed an open-response task. From the inductive analysis of student written responses, 22 codes emerged that reflected students’ conceptions of the climate system. From these codes, three path diagrams were constructed that illustrate these students’ conceptions about how a climate system influences climate and how greenhouse gases and global warming impact the climate system. A generalized model of students’ conception of a climate system was generated. Students in this study conceptualized a climate system in a unidirectional, linear, cause and effect relationship that emphasized the atmospheric component of the climate system.  相似文献   
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While there has been research conducted on public views about ethical and social aspects of the National DNA Database (NDNAD), there is little which focuses on views of young people, in particular those whose details are held on the NDNAD. We describe an engagement activity developed in South Wales to engage young offenders with ethical and social issues surrounding the NDNAD--a Mock Trial--and how we facilitated the presentation of their views to policy makers. We discuss the successes and challenges we encountered with engaging young offenders, decisions that the young people reached about possible future policies for the NDNAD at the Mock Trial, and their contribution to the decision-making process.  相似文献   
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IntroductionOesophageal varices are routinely diagnosed by esophagogastroduodenoscopy (EGD), and their bleeding has high mortality. We aimed to evaluate diagnostic performance of biochemical tests in comparison to elastography-based approaches, as non-invasive alternatives to EGD, for ruling-out high risk oesophageal varices (HRV).Material and methodsRetrospective analysis of patients (N = 861) who underwent liver stiffness measurement (LSM) by transient elastography (TE) in a single centre over 5-year period, with available results of EGD (within 3 months from LSM). Only patients with suspicion of compensated advanced chronic liver disease (cACLD) defined by LSM ≥ 10 kPa were included comprising the final cohort of 73 subjects. Original and expanded Baveno VI criteria (B6C), controlled attenuation parameter (CAP), platelet count (PLT), aspartate aminotransferase to PLT ratio index (APRI), Fibrosis-4 index (FIB4), model for end stage liver disease (MELD) score were evaluated against the results of EGD that served as the reference method.ResultsAnalysed patients had median age 62 years, 59/73 (0.81) were males, 54/73 (0.74) had alcoholic/non-alcoholic fatty liver disease, and 21/73 (0.29) had HRV. In multivariate logistic regression analysis only LSM and PLT were independently associated with HRV. The best performing tests for ruling-out HRV (% of spared EGD; % of missed HRV) were respectively: LSM < 20 kPa (53.4%; 0%), B6C (38%; 0%), Expanded B6C (47.9%; 4.8%); PLT > 214x109/L (21.9%; 0%); FIB4 ≤ 1.8 (21.4%; 0%), APRI ≤ 0.34 (12.3%; 0%). CAP, MELD = 6 alone or combined with PLT > 150(x109/L) did not show acceptable performance.ConclusionThe best performing biochemical tests for ruling-out HRV in our cohort of patients were PLT and FIB-4, but they were still outperformed by elastography-based approaches.Keyword: portal hypertension, cirrhosis, platelet count, esophageal varices, non-invasive tests  相似文献   
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Lead poisoning is well documented in persons occupationally exposed to lead. What is less known is, that even in persons working in lead based industries, the effect of lead and the appearance of signs and symptoms of lead poisoning is genetically determined. Three genes related to lead metabolism, exhibiting polymorphism have already been demonstrated-δALA-dehydratase, Vitamin D receptor gene and Hemochromatosis gene. These alleles determine the susceptibility of the individuals to lead. We present here a case of a lead acid battery worker, who presented without any signs and symptoms of lead poisoning except for a very high level of blood lead (82.8μg/dl and 47.5μg/dl 9 months later)  相似文献   
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This research advances the understanding of how to define, evaluate, and promote e‐learning success from an information systems perspective. It introduces the E‐Learning Success Model, which posits that the overall success of an e‐learning initiative depends on the attainment of success at each of the three stages of e‐learning systems development: system design, system delivery, and system outcome. To study this model, an online version of an undergraduate quantitative methods core course for business students is developed using a prototyping strategy. Four cycles of development are traced, each comprised analysis, design, implementation, testing, and enhancement. Findings from the study confirm the validity of using the proposed success model for e‐learning success assessment. In addition, an action research methodology is also found to be a valuable impetus for promoting e‐learning success through an iterative process of diagnosing, action planning, action taking, evaluating, and learning.  相似文献   
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The paper discusses children’ attitudes towards school and learning soon after entering primary school in Hungary. First and second grade primary school students (N?=?33) were interviewed. The interviews explored the following questions: What are the teachers’ and the children’s roles in the classroom? What is learning? Where do children learn? What kind of learning strategies do students use in arithmetic and reading? How are students evaluated in the school? What do students like best about school? The data suggest that the children quickly adapt to the school environment and, on the whole, have a positive attitude towards school and learning but—with a few exceptions—their views on the role of schooling in life reflect traditional, school subject centred goals and values and little awareness of the learning process.  相似文献   
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