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伯纳德·希尔著高秋芳 《自然科学博物馆研究》2018,(1):84-92
本文以科学博物馆和科学中心的发展阶段为线索,综述了几个世纪以来科学传播的历史发展,阐述了科学实践如何嵌入到博物馆的展览实践之中并从中发展起来,以及关于科学在社会中的地位的观念变化如何在科学博物馆和科学中心得到反映,还展现了日益受到关注的科学传播如何在科学博物馆和科学中心层面体现出以公众需求为本。 相似文献
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Bernard Beck 《Multicultural Perspectives》2016,18(1):29-32
Courtship is a fertile setting for culturally defined strategies. A common form of competition is criticizing the other group for being inadequate mates. Stories about romance between human beings and non-human participants allow such criticism. Movies about men finding mechanical partners are common. Non-human females are seen as more satisfactory than women, especially when women are transforming their roles to be less subservient. 相似文献
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Bernard J. Jansen 《Information processing & management》2018,54(2):159-174
With the noted popularity of social networking sites, people increasingly rely on these social networks to address their information needs. Although social question and answering is potentially an important venue seeking information online, it, unfortunately, suffers from a problem of low response rate, with the majority of questions receiving no response. To understand why the response rate of social question and answering is low and hopefully to increase it in the future, this research analyzes extrinsic factors that may influence the response probability of questions posted on Sina Weibo. We propose 17 influential factors from 2 different perspectives: the content of the question, and the characteristics of the questioner. We also train a prediction model to forecast a question's likelihood of being responded based on the proposed features We test our predictive model on more than 60,000 real-world questions posted on Weibo, which generate more than 600,000 responses. Findings show that a Weibo's question answerability is primarily contingent on the questioner versus the question. Our findings indicate that using appreciation emojis can increase a question's response probability, whereas the use of hashtags negatively influences the chances of receiving answers. Our contribution is in providing insights for the design and development of future social question and answering tools, as well as for enhancing social network users’ collaboration in supporting social information seeking activities. 相似文献
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Hui-ping Lin Jun Lin Juan Li Jing-hong Xu Christian Mehl 《Journal of Zhejiang University. Science. B》2016,17(11):864-873
Resin-dentin bond degradation is a major cause of restoration failures. The major aim of the current study was to evaluate the impact of a remineralization medium on collagen matrices of hybrid layers of three different adhesive resins using nanotechnology methods. Coronal dentin surfaces were prepared from freshly extracted premolars and bonded to composite resin using three adhesive resins (FluoroBond II, Xeno-III-Bond, and iBond). From each tooth, two central slabs were selected for the study. The slabs used as controls were immersed in a simulated body fluid (SBF). The experimental slabs were immersed in a Portland cement-based remineralization medium that contained two biomimetic analogs (biomineralization medium (BRM)). Eight slabs per group were retrieved after 1, 2, 3, and 4 months, respectively and immersed in Rhodamine B for 24 h. Confocal laser scanning microscopy was used to evaluate the permeability of hybrid layers to Rhodamine B. Data were analyzed by analysis of variance (ANOVA) and Tukey’s honest significant difference (HSD) tests. After four months, all BRM specimens exhibited a significantly smaller fluorescent area than SBF specimens, indicating a remineralization of the hybrid layer (P≤0.05). A clinically applicable biomimetic remineralization delivery system could potentially slow down bond degradation. 相似文献
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The retention and extinction of a visual discrimination was examined in BALB/c mice. The mice were trained to perform a go/no-go discrimination task in parallel runways. Initial training resulted in an intermediate level of performance. Testing consisted of an additional session using either retention (Experiment 1) or extinction (Experiment 2) at one of five time intervals between 1 and 30 days. It was found in Experiment 1 that forgetting progressively increased over intervals of between 14 and 30 days. In Experiment 2, extinction testing induced more impairment of performance, so that forgetting occurred earlier relative to retention testing in Experiment 1. However, in both experiments, the measure of performance by a discrimination ratio revealed the same amount of forgetting when the training-test interval was 30 days. These results define the forgetting curve for such a discrimination by mice. They are discussed in terms of possible factors involved in forgetting. 相似文献
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The role of incentive learning in instrumental performance following a shift in the degree of water deprivation was analyzed in three experiments. In Experiments 1A and IB, rats trained to perform an instrumental action reinforced with either sucrose or maltodextrin solutions when in a high-deprivation state were subsequently shifted to a low-deprivation state and tested in extinction. This within-state shift in water deprivation reduced instrumental performance only when the animals had been exposed to the reinforcer in the low-deprivation state prior to instrumental training. In Experiment 2, a concurrent training procedure was used to assess whether the change in the value of the reinforcer brought about by preexposurewas mediated by the contingency between the instrumental action and the reinforcer. Preexposure to the reinforcer under the low-deprivation state produced a selective reduction of the performance of the action upon which it was contingent during training when testing was conducted in extinction following a shift from the high- to the low-deprivation state. These experiments provide evidence that animals have to learn about the incentive value of a reinforcer in a particular motivational state through exposure to the reinforcer in that state. 相似文献