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11.
In this study, we simulated deformation and surfactant distribution on the interface of a surfactant-covered droplet using optical tweezers as an external source. Two optical forces attracted a single droplet from the center to both sides. This resulted in an elliptical shape deformation. The droplet deformation was characterized as the change of the magnitudes of surface tension and optical force. In this process, a non-linear relationship among deformation, surface tension, and optical forces was observed. The change in the local surfactant concentration resulting from the application of optical forces was also analyzed and compared with the concentration of surfactants subjected to an extensional flow. Under the optical force influence, the surfactant molecules were concentrated at the droplet equator, which is totally opposite to the surfactants behavior under extensional flow, where the molecules were concentrated at the poles. Lastly, the quasi-equilibrium surfactant distribution was obtained by combining the effects of the optical forces with the extensional flow. All simulations were executed by the lattice Boltzmann method which is a powerful tool for solving micro-scale problems.  相似文献   
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A technology enhanced learning and teaching (TELT) solution, radiological anatomy (RA) eLearning, composed of a range of identification‐based and guided learning activities related to normal and pathological X‐ray images, was devised for the Year 1 nervous and locomotor course at the Faculty of Medicine, University of Southampton. Its effectiveness was evaluated using a questionnaire, pre‐ and post‐tests, focus groups, summative assessment, and tracking data. Since introduced in 2009, a total of 781 students have used RA eLearning, and among them 167 Year 1 students in 2011, of whom 116 participated in the evaluation study. Students enjoyed learning (77%) with RA eLearning, found it was easy to use (81%) and actively engaged them in their learning (75%), all of which were associated to the usability, learning design of the TELT solution and its integration in the curriculum; 80% of students reported RA eLearning helped their revision of anatomy and 69% stated that it facilitated their application of anatomy in a clinical context, both of which were associated with the benefits offered by the learning and activities design. At the end of course summative assessment, student knowledge of RA eLearning relevant topics (mean 80%; SD ±16) was significantly better as compared to topics not relevant to RA eLearning (mean 63%; SD ±15) (mean difference 18%; 95% CI 15% to 20%; P < 0.001). A well designed and integrated TELT solution can be an efficient method for facilitating the application, integration, and contextualization of anatomy and radiology to create a blended learning environment. Anat Sci Educ 7: 350–360. © 2013 American Association of Anatomists.  相似文献   
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By combining research on interorganizational learning (IOL) with that on IT-enabled collaboration, this study examines the role of electronic collaboration (e-collaboration) enabled through the use of interorganizational information systems in the development of a firm's capabilities such as IOL. Moreover, this study examines IOL as a capability posited between electronic collaboration and firm performance. Finally, we conceptualize IOL as a multidimensional construct composed of information sharing, relationship-specific knowledge memory, and the development of shared meaning and verify the relationships between them. The study provides an empirical analysis of the proposed model and hypotheses by considering data from various industries. The results indicate that e-collaboration was positively related to all three components of IOL. In terms of the relationships between these components, information sharing had a positive effect on relationship-specific knowledge memory, which in turn facilitated the development of shared meaning. Only the development of shared meaning had a significant effect on firm performance. Discussions and implications of the results are provided.  相似文献   
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Congenital atresia of the left main coronary artery is a rare occurrence, and surgical revascularizationbypass graft is required. We here report a rare case of congenital coronary anomaly in an infant. A 10-month-old male infant was admitted to the hospital with heart failure symptoms. Echocardiographic examinations revealed mitral valve regurgitation and ischemic changes of the anterolateral papillary muscle and chordae. Coronary angiography showed atresia of the left main coronary artery with a severe hypoplastic left anterior descending artery and a circumflex coronary artery. Unfortunately, sudden cardiac arrest occurred after catheterization and the infant did not recover despite of immediate cardiopulmonary resuscitation. Further studies are needed to find a newer diagnostic method to detect coronary anomaly in an infant, and coronary angiography, if necessary, has to be performed very carefully.  相似文献   
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The purpose of this study was to assess, evaluate, and compare the competitive advantages of the human resource development systems of advanced countries. The Global Human Resource Development Index was utilized for this study, since it has been validated through an expert panel’s content review and analytic hierarchy process. Using a sample of 34 OECD member countries, the following conclusions were drawn. First, Switzerland, Sweden, and United States ranked top three in order in National Human Resource Development (NHRD) competitiveness and such Nordic countries as Sweden, Finland, Denmark, Norway, and Iceland showed outstanding NHRD competitiveness. Second, thirty-four countries differed significantly in key aspects of supply, demand, environment, and supporting systems of NHRD. Strong, intermediate, and weak groups classified based on NHRD competitiveness significantly differed from one another in all factors of the NHRD system. Third, changes in NHRD competitiveness between 2005 and 2011 did not exhibit specific patterns depending on the level of economic development. Fourth, little changes in NHRD system occurred in a short period of time. The most significant positive changes in NHRD competitiveness were identified in only two cases of Luxemburg (△6) and Poland (△6) among 34 countries. Only striking case of decrease in NHRD competitiveness was Israel (▽6). The findings of this research will be able to assist each country in identifying its strengths and weaknesses in the NHRD system.  相似文献   
17.
Integration of microfluidic devices with pressure-driven, self-powered fluid flow propulsion methods has provided a very effective solution for on-chip, droplet blood testing applications. However, precise understanding of the physical process governing fluid dynamics in polydimethylsiloxane (PDMS)-based microfluidic devices remains unclear. Here, we propose a pressure-driven diffusion model using Fick''s law and the ideal gas law, the results of which agree well with the experimental fluid dynamics observed in our vacuum pocket-assisted, self-powered microfluidic devices. Notably, this model enables us to precisely tune the flow rate by adjusting two geometrical parameters of the vacuum pocket. By linking the self-powered fluid flow propulsion method to the sedimentation, we also show that direct plasma separation from a drop of whole blood can be achieved using only a simple construction without the need for external power sources, connectors, or a complex operational procedure. Finally, the potential of the vacuum pocket, along with a removable vacuum battery to be integrated with non-PDMS microfluidic devices to drive and control the fluid flow, is demonstrated.  相似文献   
18.
This study examined employees’ perceptions of interpersonal competence at work through the research methodology known as concept mapping. The purpose of this study was to identify the phenomenally derived components of interpersonal competence in work environments and employees’ underlying cognitive structures of interpersonal competence at work. Multidimensional scaling analysis indicated that the participants conceptualized interpersonal competence in the following two dimensions: (i) work-specific domain versus general domain and (ii) unilateral domain versus bilateral domain. In addition, hierarchical clustering on the MDS coordinates produced six clusters: Caring & Considerate, Sociable & Out-going, Kind & Gentle, Reliable & Leadership skills, and Confident & Responsible. Our results were discussed with respect to future research and educational approaches to the issues surrounding interpersonal competencies at work.  相似文献   
19.
Higher Education - Originating from the field of physical education, physical literacy is an individual disposition that accentuates the importance of lifelong physical activity. Sport education is...  相似文献   
20.
Learning progressions are theoretical models that describe learning of scientific ideas and practices over time. These hypothetical progressions need to be tested and refined in order to productively inform instruction and assessment. In this paper, we report our attempts to revise a learning progression in genetics. In particular, we focused on two constructs that embody core ideas in classical genetics and one molecular construct. The revisions are based on analysis of pre‐ and postinterview data obtained from sixty 11th grade students before and after they engaged in a 10‐week unit that addressed these concepts. We found that while many of the students held ideas that aligned with the progression, there were several distinct dimensions of student reasoning that were not captured and led to substantial revisions of the constructs including: (a) the splitting of the construct dealing with meiosis (E) into two subconstructs (E1‐physical passage of genetic information and E2 – the role of sex cells), (b) the addition of new levels to constructs dealing with the universal nature and organization of the genetic code (A) and construct (F). For Construct A, the lower levels were expanded to include ideas about the localization of DNA in cells and to include ideas about the composition of DNA that were not captured in the progression. Revisions to Construct F included the expansion of existing levels and the addition of modes of inheritance such as codominance and incomplete dominance. The research we present offers insights about a methodological approach that can be used to test and refine progressions, as well as insights about student learning in genetics as we further describe and expand the stepping‐stone ideas in the progression and discuss further the multidimensional nature of learning progressions.  相似文献   
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