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Like excellence, internationality has evolved into a key concept for German universities. This article reconstructs the manifold genesis of internationality as a principle for stratificatory claims on the basis of science policy documents. At the levels of student exchange, researcher mobility, and university cooperation, three changes are elaborated upon: the transition from the medieval universitas of the nationes to the national university, the increasing competitive orientation of a concept of internationality based on cooperation and cultural exchange, and the transformation of internationality under the auspices of excellence. At the same time, it will be shown how international understanding, exchange, and competition as guiding principles of an internationalization discourse are enacted differently in varying historical contexts. It will be demonstrated that internationality as a sign of excellence becomes a strategy for universities to position themselves as superior in their respective fields.  相似文献   
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Background and objective

Stroke volume variation (SVV) has high sensitivity and specificity in predicting fluid responsiveness. However, sinus rhythm (SR) and controlled mechanical ventilation (CV) are mandatory for their application. Several studies suggest a limited applicability of SVV in intensive care unit (ICU) patients. We hypothesized that the applicability of SVV might be different over time and within certain subgroups of ICU patients. Therefore, we analysed the prevalence of SR and CV in ICU patients during the first 24 h of PiCCO-monitoring (primary endpoint) and during the total ICU stay. We also investigated the applicability of SVV in the subgroups of patients with sepsis, cirrhosis, and acute pancreatitis.

Methods

The prevalence of SR and CV was documented immediately before 1241 thermodilution measurements in 88 patients.Results: In all measurements, SVV was applicable in about 24%. However, the applicability of SVV was time-dependent: the prevalence of both SR and CV was higher during the first 24 h compared to measurements thereafter (36.1% vs. 21.9%; P<0.001). Within different subgroups, the applicability during the first 24 h of monitoring ranged between 0% in acute pancreatitis, 25.5% in liver failure, and 48.9% in patients without pancreatitis, liver failure, pneumonia or sepsis.

Conclusions

The applicability of SVV in a predominantly medical ICU is only about 25%–35%. The prevalence of both mandatory criteria decreases over time during the ICU stay. Furthermore, the applicability is particularly low in patients with acute pancreatitis and liver failure.
  相似文献   
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The findings of a pilot study designed to evaluate a computer system developed to assist in the teaching of reading to beginners are presented. The system uses digitised speech and the content is based upon a reading scheme already in use in the schools. Twenty children, ten in the intervention group and ten in the control group, in two schools were involved over a four-week period. Subjects were tested on a standardised reading test, a list of the 30 most frequently occurring words in written English, and on words from the published scheme. The experimental group improved their scores significantly more than the control group only on the standardised reading test. The results suggest the system can be helpful and that its effect goes beyond the words being practised.  相似文献   
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Massive Online Open Courses (MOOCs) provide opportunities to learn a vast range of subjects. Because MOOCs are open to anyone with computer access and rarely have prerequisite requirements, the range of student backgrounds can be far more varied than in conventional classroom-based courses. Prior studies have shown that misconceptions have a huge impact on students' learning performance; however, no study has empirically examined the relationship between misconceptions and learning persistence. This study of 12,913 MOOC-takers examines how students' misconceptions about the upcoming course material affect course completion. Using a survival analysis approach, we found that, controlling for the score in a pre-course test, students holding more misconceptions had a higher dropout rate at the start of the course, an effect that diminished over time. Other student variables were found to have a positive impact on survival that persisted throughout the entire course: U.S. location, higher age, an intention to complete, better English skills, prior familiarity with the subject, motivation to earn a certificate, and score and time spent on the previous problem set (homework). By contrast, student gender, education level, number of previous MOOCs completed, and motivation to participate in online discussion forums did not affect survival.  相似文献   
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Science fiction remains an alien dimension of the history of science. Historical and literary studies of science have become increasingly attentive to various "literary technologies" in scientific practice, the metaphorical features of scientific discourse, and the impact of popular science writing on the social development of scientific knowledge. But the function of science fiction and even literature as such in the history of scientific and technological innovation has often been obscured, misconstrued, or repudiated owing to conventional notions of authorship, influence, and the organic unity of texts. The better to address those close encounters where scientific practice makes use of speculative fiction, this essay proposes that we instead analyze such exchanges as processes of appropriation, remixing, and modification.  相似文献   
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Current barriers hindering data-driven discoveries in deep-time Earth (DE) include: substantial volumes of DE data are not digitized; many DE databases do not adhere to FAIR (findable, accessible, interoperable and reusable) principles; we lack a systematic knowledge graph for DE; existing DE databases are geographically heterogeneous; a significant fraction of DE data is not in open-access formats; tailored tools are needed. These challenges motivate the Deep-Time Digital Earth (DDE) program initiated by the International Union of Geological Sciences and developed in cooperation with national geological surveys, professional associations, academic institutions and scientists around the world. DDE’s mission is to build on previous research to develop a systematic DE knowledge graph, a FAIR data infrastructure that links existing databases and makes dark data visible, and tailored tools for DE data, which are universally accessible. DDE aims to harmonize DE data, share global geoscience knowledge and facilitate data-driven discovery in the understanding of Earth''s evolution.  相似文献   
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