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From a representative survey of 2,000 individuals, we study whether consumption of music through streaming services, like Spotify or YouTube, is a substitute or a complement to physical music consumption modes, such as CDs and live music. Controlling for the taste for music, various socio-demographic characteristics and the usual determinants of music consumption either offline (radio, TV, friends/relatives) or online (online recommendations, social networks), our results show that free music streaming (where the consumer does not possess the music but only has access to it) has no significant effect on CD sales and affects positively live music attendance, but only for national or international artists who are more likely to be available on streaming services.  相似文献   
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This paper reports on how Maria (pseudonym), a non-native English speaker (NNES) and preservice teacher (PST) of English as an additional language (EAL), developed her professional identity during the practicum in an Australian secondary school. Drawing on activity theory, the study identified contradictions in Maria’s practicum activity and examined how Maria’s professional identity developed through her negotiation of the contradictions. Data included interviews with Maria before, during and after the practicum, her reflections, an interview with her school mentor (Ms Davies, pseudonym), and relevant documents. The findings reveal that Maria experienced contradictions between her multiple identities of NNES, student, becoming teacher, and classroom teacher, between her mentor’s teaching approach and that of her own, and between her practice and rules. The findings provide implications for researching teacher identity and supporting preservice EAL teachers in developing productive teacher identities during the practicum.  相似文献   
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This article is concerned with the control of a Semi-Active suspension system of a 7DOF Full Vehicle model, equipped with four Electro Rheological (ER) dampers, taking into account their incipient dissipativity constraints. Herein, a real-time, fast, advanced control structure is presented within the Model Predictive Control framework for Linear Parameter Varying (LPV) systems. The control algorithm is developed to provide a suitable trade-off between comfort and handling performances of the vehicle in a very limited sampling period (Ts=5ms), in view of a possible realtime implementation on a real vehicle. The control structure is tested and compared to other standard fast control approaches. Full nonlinear realistic simulation results illustrate the overall good operation and behaviour of the proposed control approach.  相似文献   
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We present a microfluidic approach to characterizing temperature-dependent biomolecular interactions. Solvated L-arginine vasopressin (AVP) and its immobilized RNA aptamer (spiegelmer) were allowed to achieve equilibrium binding in a microchip at a series of selected temperatures. Unbound AVP were collected and analyzed with matrix-assisted laser desorption∕ionization mass spectrometry (MALDI-MS), yielding melting curves that reveal highly temperature-dependent zones in which affinity binding (36–45 °C) or dissociation (25–33 °C and 50–65 °C) occurs. Additionally, temperature-dependent binding isotherms were constructed; from these, thermodynamic quantities involved in binding were extracted. The results illustrated a strong change in heat capacity of interaction for this system, suggesting a considerable thermodynamic influence controlling vasopressin-spiegelmer interaction.  相似文献   
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Education and Information Technologies - Analysing pre-service teachers’ learning design conversations in relation to Technological Pedagogical and Content Knowledge (TPACK) framework to...  相似文献   
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Education and Information Technologies - Peer assessment has an important role in teaching and learning nowadays. However, the existing techniques tend to be limited due to a lack of a suitable...  相似文献   
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In the context of social media, users usually post relevant information corresponding to the contents of events mentioned in a Web document. This information posses two important values in that (i) it reflects the content of an event and (ii) it shares hidden topics with sentences in the main document. In this paper, we present a novel model to capture the nature of relationships between document sentences and post information (comments or tweets) in sharing hidden topics for summarization of Web documents by utilizing relevant post information. Unlike previous methods which are usually based on hand-crafted features, our approach ranks document sentences and user posts based on their importance to the topics. The sentence-user-post relation is formulated in a share topic matrix, which presents their mutual reinforcement support. Our proposed matrix co-factorization algorithm computes the score of each document sentence and user post and extracts the top ranked document sentences and comments (or tweets) as a summary. We apply the model to the task of summarization on three datasets in two languages, English and Vietnamese, of social context summarization and also on DUC 2004 (a standard corpus of the traditional summarization task). According to the experimental results, our model significantly outperforms the basic matrix factorization and achieves competitive ROUGE-scores with state-of-the-art methods.  相似文献   
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In this paper, we present an on-chip hand-powered membrane pump using a robust patient-to-chip syringe interface. This approach enables safe sample collection, sample containment, integrated sharps disposal, high sample volume capacity, and controlled downstream flow with no electrical power requirements. Sample is manually injected into the device via a syringe and needle. The membrane pump inflates upon injection and subsequently deflates, delivering fluid to downstream components in a controlled manner. The device is fabricated from poly(methyl methacrylate) (PMMA) and silicone, using CO2 laser micromachining, with a total material cost of ∼0.20 USD/device. We experimentally demonstrate pump performance for both deionized (DI) water and undiluted, anticoagulated mouse whole blood, and characterize the behavior with reference to a resistor-capacitor electrical circuit analogy. Downstream output of the membrane pump is regulated, and scaled, by connecting multiple pumps in parallel. In contrast to existing on-chip pumping mechanisms that typically have low volume capacity (∼5 μL) and sample volume throughput (∼1–10 μl/min), the membrane pump offers high volume capacity (up to 240 μl) and sample volume throughput (up to 125 μl/min).  相似文献   
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