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11.
Surface analysis is critical for the validation of microfluidic surface modifications for biology, chemistry, and physics applications. However, until now quantitative analytical methods have mostly been focused on open surfaces. Here, we present a new fluorescence imaging method to directly measure the surface coverage of functional groups inside assembled microchannels over a wide dynamic range. A key advance of our work is the elimination of self-quenching to obtain a linear signal even with a high density of functional groups. This method is applied to image the density and monitor the stability of vapor deposited silane layers in bonded silicon/glass micro- and nanochannels.  相似文献   
12.
In this article, we propose a nonlinear dynamic latent class structural equation modeling (NDLC-SEM). It can be used to examine intra-individual processes of observed or latent variables. These processes are decomposed into parts which include individual- and time-specific components. Unobserved heterogeneity of the intra-individual processes are modeled via a latent Markov process that can be predicted by individual- and time-specific variables as random effects. We discuss examples of sub-models which are special cases of the more general NDLC-SEM framework. Furthermore, we provide empirical examples and illustrate how to estimate this model in a Bayesian framework. Finally, we discuss essential properties of the proposed framework, give recommendations for applications, and highlight some general problems in the estimation of parameters in comprehensive frameworks for intensive longitudinal data.  相似文献   
13.
When reading conflicting science-related texts, readers may attend to cues which allow them to assess plausibility. One such plausibility cue is the use of graphs in the texts, which are regarded as typical of ‘hard science’. The goal of our study was to investigate the effects of the presence of graphs on the perceived plausibility and situation model strength for conflicting science-related texts, while including the influence of readers’ amount of experience with scientific texts and graphs as a potential moderator of these effects. In an experiment mimicking web-based informal learning, 77 university students read texts on controversial scientific issues which were presented with either graphs or tables. Perceived plausibility and situation model strength for each text were assessed immediately after reading; reader variables were assessed several weeks prior to the experiment proper. The results suggest that graphs can indeed serve as plausibility cues and thus boost situation model strength for texts which contain them. This effect was mediated by the perceived plausibility of the information in the texts with graphs. However, whether readers use graphs as plausibility cues in texts with conflicting information seems to depend also on their amount of experience with scientific texts and graphs.  相似文献   
14.
Ohne ZusammenfassungÜbersetzt aus Documents administratifs, veröffentlicht in L'Éducation Nationale, Nr. 35, Dezember 1956. Eine englische Übersetzung dieser Präambel veröffentlichten wir in unserer letzten Nummer (III/4).  相似文献   
15.
In November 2013, local citizens of Munich and the surrounding districts voted in a referendum against a city’s bid for the 2022 Winter Olympic Games. Since this is but one example of such a failed referendum—others being the ones in Poland, Switzerland and Austria—it is astonishing that it seems to become common practice to conduct public polls regarding the bid for a mega sport event. The city of Hamburg, for instance, will be the next German city to hold a referendum on its bid for the 2024 Olympic Games in November 2015. Against this backdrop, we introduce the ‘Arenatheoretical Model’ into mega event research and conduct a qualitative content analysis of the media coverage on the Munich referendum. Three nationwide German newspapers were analysed as the model suggests that this coverage has a profound influence on the public opinion in other parts of the country. The aim was to identify arguments brought forward to explain the outcome of the referendum. Besides a number of other issues, such as concerns regarding event legacy and regional matters, major findings stress the significance of a damaged brand image of international sport organisations and ‘their’ events. Based on these insights, a number of implications can be derived for other cities/nations and sport organisations that depend on a favourable public opinion in their efforts to stage a mega sport event.  相似文献   
16.
This overview focuses on Europe, a linguistically diverse region and moreover home to a number of minority languages. Over the past five decades, the focus of research on bi- or multilingual education has shifted from an initial emphasis on speakers?? identities and their membership of homogenous imagined communities to an interest in learners?? diverse and not usually clear-cut (multi)lingual repertoires. In the wake of regionalist movements emerging in the 1960s and an increase in transmigration and global mobility from the 1990s onwards, different models of practices and policies have developed in European bi- and multilingual education. The author discerns four different policy orientations and three types of structured language distribution practices. The challenge for policy-makers and schools is to choose carefully which of these models work best in their particular environments.  相似文献   
17.
It is well established that rapid automatised naming (RAN) correlates with reading ability. Despite several attempts, no single component process (mediator) has been identified that fully accounts for the correlation. The present paper estimated the explanatory value of several mediators for the RAN–reading correlation. One hundred and sixty‐nine preschool students were given measures of RAN and additional measures of phonological awareness, lexical search speed, letter knowledge and paired associate learning. Their reading skills were tested a year later along with speed of processing. The influence of the mediators on the RAN–reading correlation was estimated as indirect effects in mediation analyses. Phonological awareness and letter knowledge significantly mediated the RAN–reading relationship, each accounting for a moderate part of the correlation between RAN and reading fluency. Thus, the RAN–reading correlation was partly, but not fully, accounted for by precursors of reading that are currently known.  相似文献   
18.
The manipulation of ribosomal RNA (rRNA) extracted from E. coli cells by dielectrophoresis (DEP) has been demonstrated over the range of 3 kHz-50 MHz using interdigitated microelectrodes. Quantitative measurement using total internal reflection fluorescence microscopy of the time dependent collection indicated a positive DEP response characterized by a plateau between 3 kHz and 1 MHz followed by a decrease in response at higher frequencies. Negative DEP was observed above 9 MHz. The positive DEP response below 1 MHz is described by the Clausius-Mossotti model and corresponds to an induced dipole moment of 3300 D with a polarizability of 7.8×10(-32) F m(2). The negative DEP response above 9 MHz indicates that the rRNA molecules exhibit a net moment of -250 D, to give an effective permittivity value of 78.5 ε(0), close to that of the aqueous suspending medium, and a relatively small surface conductance value of ~0.1 nS. This suggests that our rRNA samples have a fairly open structure accessible to the surrounding water molecules, with counterions strongly bound to the charged phosphate groups in the rRNA backbone. These results are the first demonstration of DEP for fast capture and release of rRNA units, opening new opportunities for rRNA-based biosensing devices.  相似文献   
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20.
Licensing as a commercialisation strategy for new technology-based firms   总被引:1,自引:0,他引:1  
We investigate licensing as a commercialisation strategy for new technology-based firms (NTBFs) in the biopharmaceutical industry using a combination of survey and database research methods. We found that most firms in our sample were not fully integrated regardless of their company age which is consistent with the picture of NTBFs as agents of technology transfer. Comparing fully and not-fully integrated firms we find differences in the use of licensing strategies. According to Ford and Ryan [Harvard Business Review 59 (1981) 117] fully integrated companies apply licensing for strategic reasons and for financially unattractive projects. Our results provide partial support for this theory.  相似文献   
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