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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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Membership in civil rights and women's liberation organizations in the United States was tracked over a period of 22 years. Men's social and fraternal organizations were also tracked as a comparison group. Systematic fluctuations in membership suggest that this criterion would be useful for identifying the developmental stages of a movement. In addition, peaks in membership were correlated with historical events. Implications and directions for future research are discussed.  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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In 1730, shortly before his death, the Paris anatomist Joseph-Guichard Duverney wrote his will, leaving his anatomical specimens to the Académie des Sciences, of which he was a member. But the will was disputed by Pierre Chirac, supervisor of the Jardin du Roi where Duverney, as professor of anatomy, had performed most of the dissections that produced the specimens. The ensuing debate between Chirac and René-Antoine Ferchault de Réaumur, arguing for the Académie, reveals the tensions surrounding both the concept of intellectual property in this period and the collective enterprise in natural philosophy. The differing roles and audiences of the Académie and the Jardin were central to this debate. In addition, this essay explores the origins and significance of the anatomical specimens themselves and their changing role in instruction and display, as well as the transition from the cabinet of curiosities to the natural history museum.  相似文献   
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本文对金缕梅科弗特吉族(Molinadendron和Matudaea除外)的细胞核核糖体DNA ITS片段进行了序列分析,在此基础上对该族的演化关系、尤其是中国特有属银缕梅属的系统位置进行了最简约分支分析。基本结果如下:其一,蚊母族和狭义的弗特吉族均不形成自己的单系分支,因此,支持Endress的处理,即合并两族为广义的弗特吉族;其二,银缕梅属同帕罗堤属有着密切的亲缘关系,支持形态学和解剖学结论;其三,根据该片段核苷酸序列的演化速率推算出的银缕梅属和帕罗堤属间分化时间为晚中新世。此结论大致与化石记录相符。  相似文献   
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OBJECTIVE: According to mandatory reporting laws for professionals, the relationship between initial recognition that a child may have been abused and the subsequent reporting of that suspected case of child abuse to the responsible agency would, at first glance, appear to be clear. However, this relationship has developed into one of the major social policy controversies of the recent past. Our major goal is to present research findings that address this social policy debate concerning the problems of underreporting and overreporting, focusing specifically on teachers. METHOD: A factorial survey design, that combines the advantages of the factorial experiment with those of surveys, was employed in a probability sample of teachers (N=480) who responded to vignettes in which case characteristics were systematically manipulated. Teachers responded with judgments about whether the vignette was child abuse and the likelihood that they would report this suspected case. Characteristics of the teachers and their work setting (school) were also measured. RESULTS: When comparing the teachers' recognition and reporting scores, we found that they gave the same score for 63% of the vignettes they judged, gave higher reporting than recognition scores (overreporting) for 4% of the vignettes, and gave higher recognition than reporting scores (underreporting) for 33% of the vignettes. Discrepancies between recognition and reporting (over and under reporting) were related to characteristics of the case, teacher, and school where the teacher was employed. CONCLUSIONS: Teachers in our Ohio sample evidence the use of professional discretion in making judgments about the recognition and reporting of child abuse and do not appear to make these judgments with equal certainty. Their use of discretion is more likely to result in underreporting than overreporting.  相似文献   
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