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1.
This study investigated the effect of including explicit nature of science (NOS) content in read-alouds of elementary science trade books on the teaching and learning of NOS. We focused on three aspects of NOS: the creative, the empirical, and the inferential NOS. The trade books were read aloud by teachers in three hierarchical levels: Level I served as a control and consisted of a trade book that remained unmodified, Level II consisted of a trade book that had been modified to include explicit references to NOS, and Level III consisted of a modified trade book accompanied by educative curriculum materials that were aimed at improving the teachers' views of NOS as well as supporting teaching about NOS. We used the Views of Nature of Science Questionnaire-form CE (VNOS-CE) preintervention and postintervention to determine changes in teachers' views of NOS and interviews preintervention and postintervention to determine changes in students' views. Audio recordings of read-alouds were used to determine changes in teaching practice, including the frequency and the quality (i.e., naïve or informed) of the NOS references in the discussions. Interviews were used to determine teachers' perceptions of the modified trade books and educative curriculum materials. We found that both teachers and students developed more informed views of the targeted NOS aspects after the intervention and that teachers addressed NOS more often, and in a more informed manner, when they had trade books that explicitly supported NOS instruction and educative curriculum materials that supported their learning about NOS. Furthermore, they perceived the intervention materials favorably. Teachers' views and practices were able to change in tandem because of the intervention materials that supported explicit NOS instruction. We highlight the need for more widespread development of similar educative curriculum materials. 相似文献
2.
Fadhaa A. Ghafil Bassim I. Mohammad Hussain S. Al-Janabi Najah R. Hadi Hayder A. Al-Aubaidy 《Indian journal of clinical biochemistry : IJCB》2021,36(1):81
Genetic variation in the angiotensin II type 1 receptor (AT1R) has an important effect on the outcome of acute coronary syndrome (ACS) initiated treatment with captopril. This study aims to investigate the impact of genetic polymorphism of AT1R (rs5186 and rs275651) on the ACS outcome in Iraqi patients treated with captopril. A total of 250 Iraqi individuals with ACS were included in this case—control study and they were divided into two study groups; Study group 1 included 125 participants who were prescribed captopril, 25 mg twice daily and study group 2 included 125 participants who received no captopril as part of their ACS treatment (control study). The AT1R gene (rs5186) CC genotype was found to be associated with ST-elevation myocardial infarction (STEMI) (Odd’s ratio (O.R) = 1.2, P = 0.7), while AC was associated with Non-ST-elevation myocardial infarction (NSTEMI) and unstable angina (UA) (O.R = 1.2, P = 0.8). AC genotype is more prone to have Percutaneous coronary intervention (PCI) after ACS attack (O.R = 1.2, P = 0.6). CC genotype had a risk to get less improvement (O.R = 1.6, P = 0.5), so might require higher doses of captopril during acute coronary insult. The AT1R gene (rs275651) AA genotype was associated with UA (O.R = 1.3, P = 0.9). AA and AT genotypes were more prone to have PCI after ACS attack (O.R = 3.9 P = 0.2, O.R = 3.5, P = 0.3 respectively) and thus requiring higher doses of captopril. We conclude that the AT1R rs5186, rs275651 genetic polymorphisms might partially affect the clinical outcome of ACS patients treated with captopril and might have captopril resistance which requires higher doses. 相似文献
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现有关税收优惠政策对企业创新活动影响的文献缺乏从整个创新链的全角度揭示税收优惠政策是否真正提高企业创新能力的探索。基于中关村科技型企业数据,本文选取税收优惠政策中典型的政策工具“研发费用加计扣除”作为研究对象,有别于已有主要从“投入”视角关注研发费用加计扣除引导作用的研究,从“投入-产出-收益”的创新链全视角,将创新过程分为技术研发阶段与技术转化阶段,以揭示研发费用加计扣除政策是否真的提升了企业创新能力。基于PSM-DID方法的实证研究结果发现:在投入端,研发费用加计扣除政策显著提高了企业的研发投入规模与强度;在产出端,研发费用加计扣除政策仅促进了研发产出规模的提升,而对于产出强度则无显著影响;在收益端,研发费用加计扣除对收益规模与强度同样有显著的促进作用。本文的发现肯定了我国研发费用加计扣除政策的引导作用,以及其在企业创新能力提升中发挥的积极作用。本文的研究思路为揭示政府创新激励政策的效果提供了新视角,研究发现为从创新链与企业创新能力的角度思考和改善政府研发税收优惠政策的管理和实施提供了新证据。 相似文献
5.
外部网络关系对企业双元创新的影响结果存在较大争议,企业维持何种状态的外部网络关系会促进双元创新,影响机理中知识吸收能力起到怎样的作用,这是亟需研究的问题。对387家企业为样本进行问卷调查,运用结构方程模型法,以知识获取能力和知识实现能力为双重中介,探析外部网络关系对企业双元创新的影响。研究结果表明:外部网络关系不同维度对双元创新具有差异化影响;网络关系强度和网络关系密度的提高以及网络关系深度的适度降低有利于渐进性创新,网络关系深度和网络关系密度的提高以及网络关系强度的适度降低更有利于突破性创新;知识吸收能力在外部网络关系对双元创新的影响中发挥部分中介作用。 相似文献
6.
Sophie Rutter Verena Blinzler Chaoyu Ye Max L. Wilson Michael D. Twidale 《Information processing & management》2019,56(3):919-938
With greater access to computational resources, people use search to address many everyday challenges in their lives, including solving technology problems. Although there are now many useful ‘how-to’ resources online (especially videos on YouTube), it can still be difficult to identify, understand, and resolve certain kinds of technical problem. While research tasks have been studied for many years and we know the tactics people use, we know far less about searchers’ tactics for how-to technical tasks that involve actually being able to apply found information to resolve a problem. Crucial to our study was developing and studying a highly realistic, how-to technical task, for which there was no single guidance resource: making a phone safe for a child. After providing 39 participants with an actual phone to fix, and a search engine to perform the task, we analysed their search tactics using retrospective cued think aloud interviews. Our primary contribution is a set of 77 tactics used, in three categories, along with detail of how common they were. We conclude that people had a lot of tactics in their repertoire. Although it was not hard for participants to find relevant information, what was hard was for participants to find information they could use; indeed only 23% of participants successfully completed the entire task. Domain knowledge affected the choice of tactics used (although not necessarily towards better task success). We discuss these influences and make design recommendations for how future search systems can support those in resolving how-to technical tasks. 相似文献
7.
BackgroundThe current state of knowledge regarding the role of non-offending fathers in supporting their sexually abused children is very scarce.ObjectiveThe objective of this study is to further our understanding of fathers’ roles following disclosure of their children’s sexual abuse (SA) by evaluating fathers’ perceptions of the impact of disclosure on their involvement and support of their children.Participants and methodThis qualitative study relies on individual semi-structured interviews conducted with 17 fathers of allegedly abused children.ResultsInductive thematic analysis first highlighted that some reported a period of disengagement from the child during which they put into question their role and attitudes, followed by a period of re-involvement. This period of difficulties experienced by some fathers in regard to their involvement towards their children was due to either their own important psychological distress, their ambivalence towards their child or even because of feelings of uneasiness experienced during physical contact with them. Despite this, findings indicate the presence of thoughts and attitudes that suggest children are a source of concern for fathers. The four forms of abuse-specific support previously observed among mothers (believing the child, seeking out professional services, protecting him/her from the offender, supporting him/her emotionally) were also observed among fathers. In accordance with the activation theory, a form of support specific to fathers, namely, encouraging the child to open up to and explore the world outside the family, thereby, fostering the child’s self-esteem development, was observed and constitutes a relevant finding.ConclusionClinical and empirical implications are discussed. 相似文献
8.
根据新常态下国家中长期社会经济发展对科技创新的战略定位,立足宏观科技管理的基本规律,紧紧围绕科技与经济脱节的核心矛盾,具体阐述我国现行科技体制存在的问题及原因。在全面梳理党的十八大以来国家以转变政府职能和调整公共政策为抓手的系列关键举措及其成效基础上,从剖析现阶段科技体制改革深化的结构性本质入手,结合科技强国目标的实现,为后续工作的推进提出对策和建议。 相似文献
9.
针对武汉市孵化器政策有效性问题,从基本政策工具和孵化器建设全过程两个角度构建二维分析模型,并对2006—2015年之间的政策文本进行量化处理,分析武汉市孵化器政策运用的过溢、不足和缺失,并提出以下对策和建议,(1)强化需求型政策工具的引导作用;(2)重视孵化器发展阶段的核心内容建设;(3)营造良好的孵化环境。 相似文献
10.
Barry J. Griffiths 《PRIMUS》2018,28(1):80-89
This paper describes an innovative way of randomly collecting handwritten homework in calculus classes with approximately 50 students using a standard deck of cards, which does not place an excessive burden on faculty with regard to grading. In addition to the increased awareness students develop in structuring a mathematical solution, the strategy has been successful in increasing classroom attendance, which the literature suggests leads to increased attainment. Along with personal observations and empirical data indicating that the scores from the randomly collected homework assignments strongly correlate with exam performance, perceptions of students are included, which show that students are strongly supportive of the method used. 相似文献