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21.
We analyze the advent and development of eight scientific fields from their inception to maturity and map the evolution of their networks of collaboration over time, measured in terms of co-authorship of scientific papers. We show that as a field develops it undergoes a topological transition in its collaboration structure between a small disconnected graph to a much larger network where a giant connected component of collaboration appears. As a result, the number of edges and nodes in the largest component undergoes a transition between a small fraction of the total to a majority of all occurrences. These results relate to many qualitative observations of the evolution of technology and discussions of the “structure of scientific revolutions”. We analyze this qualitative change in network topology in terms of several quantitative graph theoretical measures, such as density, diameter, and relative size of the network's largest component.To analyze examples of scientific discovery we built databases of scientific publications based on keyword and citation searches, for eight fields, spanning experimental and theoretical science, across areas as diverse as physics, biomedical sciences, and materials science. Each of the databases was vetted by field experts and is the result of a bibliometric search constructed to maximize coverage, while minimizing the occurrence of spurious records. In this way we built databases of publications and authors for superstring theory, cosmic strings and other topological defects, cosmological inflation, carbon nanotubes, quantum computing and computation, prions and scrapie, and H5N1 influenza. We also built a database for a classical example of “pathological” science, namely cold fusion. All these fields also vary in size and in their temporal patterns of development, with some showing explosive growth from an original identifiable discovery (e.g. carbon nanotubes) while others are characterized by a slow process of development (e.g. quantum computers and computation).We show that regardless of the detailed nature of their developmental paths, the process of scientific discovery and the rearrangement of the collaboration structure of emergent fields is characterized by a number of universal features, suggesting that the process of discovery and initial formation of a scientific field, characterized by the moments of discovery, invention and subsequent transition into “normal science” may be understood in general terms, as a process of cognitive and social unification out of many initially separate efforts. Pathological fields, seemingly, never undergo this transition, despite hundreds of publications and the involvement of many authors.  相似文献   
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College students whose test anxiety was measured completed a working memory-intensive math exam with televised distractions. Students were provided with implementation intentions (if–then plans; Gollwitzer, 1999) designed to either help them ignore the distractions (i.e., temptation-inhibiting plans) or focus more intently on the math exam (i.e., task-facilitating plans). Regression analyses showed that as test anxiety increased, the effectiveness of temptation-inhibiting implementation intentions increased, whereas task-facilitating implementation intentions increasingly harmed performance as test anxiety increased. In addition, the consequences of these plans differed significantly for those high in test anxiety. Implications for effective self-regulation by test-anxious students are discussed.  相似文献   
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The present study aimed to investigate the role of classroom climate and self‐regulation in terms of cardiac vagal tone and inhibitory control in primary school students' focused attention. A combination of direct and indirect measures was used to assess classroom climate, sustained and selective attention, and inattention behaviors among 62 first graders. We also registered students' cardiac vagal tone at rest and their levels of inhibitory control in a reaction time task. A single underlying factor combining sustained and selective attention as well as (the lack of) inattention behaviors accounted for students' focused attention. A regression analysis revealed that classroom climate, cardiac vagal tone, and inhibitory control interacted to explain first graders' focused attention. In classrooms with a negative climate, high levels of inhibitory control attenuated the negative effect of low cardiac vagal tone on students' ability to remain focused during classroom activities. Implications for theory and practice are discussed.  相似文献   
24.
Methods of sociological enquiry using data on qualifications, performance indicators, conditions for research and social background were used to investigate aspects of behaviour in young natural scientists relevant to research careers. It was shown that mathematicians and physicists were essentially more intrinsically motivated than the other cadres in the fields of natural sciences and that this manifested itself in a high intensity of work and a greater involvement in activities.  相似文献   
25.
Self-regulatory strategies of goal setting and goal striving are analyzed in three experiments. Experiment 1 uses fantasy realization theory (Oettingen, in: J. Brandstätter, R.M. Lerner (Eds.), Action and Self Development: Theory and Research through the Life Span, Sage Publications Inc, Thousand Oaks, CA, 1999, pp. 315–342) to analyze the self-regulatory processes of turning free fantasies about a desired future into binding goals. School children 8–12 years of age who had to mentally elaborate a desired academic future as well as present reality standing in its way, formed stronger goal commitments than participants solely indulging in the desired future or merely dwelling on present reality (Experiment 1). Effective implementation of set goals is addressed in the second and third experiments (Gollwitzer, Am. Psychol. 54 (1999) 493–503). Adolescents who had to furnish a set educational goal with relevant implementation intentions (specifying where, when, and how they would start goal pursuit) were comparatively more successful in meeting the goal (Experiment 2). Linking anticipated situations with goal-directed behaviors (i.e., if–then plans) rather than the mere thinking about good opportunities to act makes implementation intentions facilitate action initiation (Experiment 3).  相似文献   
26.
Drug discovery is an expensive and lengthy process. Among the different phases, drug discovery and preclinical trials play an important role as only 5–10 of all drugs that begin preclinical tests proceed to clinical trials. Indeed, current high-throughput screening technologies are very expensive, as they are unable to dispense small liquid volumes in an accurate and quick way. Moreover, despite being simple and fast, drug screening assays are usually performed under static conditions, thus failing to recapitulate tissue-specific architecture and biomechanical cues present in vivo even in the case of 3D models. On the contrary, microfluidics might offer a more rapid and cost-effective alternative. Although considered incompatible with high-throughput systems for years, technological advancements have demonstrated how this gap is rapidly reducing. In this Review, we want to further outline the role of microfluidics in high-throughput drug screening applications by looking at the multiple strategies for cell seeding, compartmentalization, continuous flow, stimuli administration (e.g., drug gradients or shear stresses), and single-cell analyses.  相似文献   
27.
Results of directed-forgetting research with pigeons are difficult to interpret because of alternative nonmemorial accounts of performance decrements and important procedural differences from comparable research with humans. Prior research has noted the absence of directed forgetting when artifacts have been removed (e.g., nonreward following forget cues and differences in response patterns on remember and forget trials in training). In this article, it is argued that, in human directed-forgetting research, presentation of a forget cue allows for the reallocation of memory maintenance to items to be remembered. In the present experiment, true directed forgetting is found when nonmemorial performance decrements are eliminated and forget cues allow for the reallocation of sample memory to test-relevant cues.  相似文献   
28.
Children have served as research subjects in several surveys on attitudes to insects and invertebrates. Most of the studies have used quantitative scoring methods to draw conclusions. This paper takes a different approach as it analyzes children's free-text comments to gain an understanding of their viewpoints. A total of 246 children aged 9–13 completed a standard questionnaire regarding their attitudes toward 18 invertebrates indigenous to Switzerland. Fourteen insect species and four other invertebrates were individually presented in a color photograph without any further background information. The children were given the opportunity to provide comments on each animal to explain the attitude score they had awarded. Nearly 5,000 comments were coded and categorized into 7 positive and 9 negative categories. A significant correlation between fear and disgust was not detected. Based on a hierarchical cluster analysis, we concluded that flying in the air versus crawling on the ground was a major differentiator for attitude and underlying reasons, only being trumped by the fear of getting stung. The visualization of our findings in a cluster heat map provided further insights into shared statement categories by species. Our analysis establishes that fear and disgust are separate emotions with regard to insects and other invertebrates. Based on our findings, we believe that prejudice-based fear and culturally evolved revulsion can be overcome. We suggest promoting environmental education programs, especially if they allow for personal experience, provide information in emotion-activating formats, and include content that resolves existing misinformation and myths.  相似文献   
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