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This paper examines what influences trust in mobile social commerce environment. Drawing on trust-based acceptance model (i.e. cognitive and emotional trust) and online review features (i.e. profile photo, linguistic style, and reported experience), we examine how these factors affect trust in mobile social commerce. Hypotheses were tested using survey data. The results of our model showed that there are significant influences of profile photo, reported experience, cognitive, and emotional trust towards trust in ms-commerce. This work contributes to existing literature by examining the roles of previous trust in mobile payments and online reviews on trust in mobile social commerce.  相似文献   
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<正>通向差异化竞争和可持续发展的新道路面对产品同质化、利润率不断下降、消费者需求日益严苛等难题,中国制造企业重生产轻服务的模式将难以维持。2008年开始的席卷全球的金融风暴引发了一系列的实体经济危机,制造企业急需走出一条通向差异化和可持续发展的新路。  相似文献   
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The paper describes a research study on visual discrimination of textual and graphic symbols on a visual display terminal (VDT) screen when viewed at eye-lo-screen distances of 61 cm and 152 cm (24 and 60 ins). Conducted as part of a development programme at McDonnell Douglas Corporation's St. Louis Aircraft Company for an Integrated Manufacturing Composites Centre (ICC), the study investigated symbol shapes, symbol sizes, symbol colours and background colours at the two viewing distances. The longer distance is representative of required placements of the VDTs at some manufacturing workstations to avoid interference with process or control equipment. Knowledge gained from the study was incorporated in the selection of the manufacturing computer information system (CIS) terminals.

All four treatments showed significant effects on visual discrimination at both viewing distances and, particularly at the 152 cm distance, the mix of symbol and background colours was highly significant. A black screen background colour with more luminous symbols such as orange, green, yellow provided much better visual discrimination at the extended viewing distance than less luminous symbols such as red and blue on a white background. Visual discrimination at the extended viewing distance, when compared with the shorter viewing distance and using symbols of equal size, was better than the loss in visual angle would suggest.

Sex and age (to age 65) did not significantly affect visual discrimination mean scores, but the variance among individuals in the 51-65 years age group was greater than for the younger age groups.

The visual discrimination scores for symbol sizes of 4 mm2 were not significantly different from the 6 mm2 symbols at the 61 cm viewing distance. The 4 mm2 symbol size was therefore adequate for visual discrimination of standalone symbols at this distance. Although 8 mm symbols were not used in this study, projections from the data indicate that such symbol sizes at 152 cm would provide comparable discrimination scores to the 4 mm2 at 61 cm.

Improved visual discrimination of standalone symbols occurs with gaps or changes in the angles of symbols, such as sets 'C' versus 'O' and 'Xl' versus'+'.  相似文献   
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Previous research studies on how to promote student participation in asynchronous online discussions have largely focused on the role of the instructor or tutor as facilitators. Not many investigated student facilitation. This article reports a qualitative study examining the facilitation techniques used by student facilitators to attract their course mates to participate in asynchronous online discussions. Data were collected from the students’ reflection logs and students’ online postings. To explore the extent to which student participation in an online discussion forum is successful, we looked at the depth of discussion threads. We deemed a student facilitator to have successfully attracted other students to participant if the discussion threads had a depth of six or more levels of students’ postings. We then examined in detail and reported the facilitation techniques that were exhibited by the student facilitators. Results showed that seven facilitation techniques were employed; the most frequently used were Socratic questioning and sharing personal opinions or experiences. We end by exploring potential implications for practice and for future research.  相似文献   
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The type II antifreeze proteins (AFPs) of smelt and Atlantic herring are homologous to the carbohydrate-recognition domains (CRDs) of Ca2+-dependent (C-type) animal lectins and, like these lectins, acquire a stable and active structure upon binding Ca2+ ions. In the C-type lectin CRD, the carbohydrate-binding site is located at a Ca2+-binding site. Site-directed mutagenesis was used to test the hypothesis that the ice-binding site of the type II AFP corresponds to the carbohydrate-binding site of the lectins. To disrupt this site in the herring AFP without perturbing the Ca2+-dependent protein fold, a double mutant was constructed that changed the Ca2+- and carbohydrate-binding motif from the galactose-type of wild-type AFP containing the sequence Gln-Pro-Asp to a mannose-type that has the sequence Glu-Pro-Asn and is also known to bind Ca2+. The mutant AFP exhibited proper Ca2+ binding, folding, and stability as demonstrated by ruthenium red staining, proteolysis protection assays, and CD spectroscopy. However, it showed no antifreeze activity (thermal hysteresis) and did not alter ice crystal morphology to form bipyramidal crystals as does the active wild-type AFP. These results demonstrate that the ice-binding site of the herring type II AFP corresponds to the carbohydrate-binding site of the C-type lectin CRDs and further suggest that this ice-binding function evolved from the carbohydrate-binding site of a preexisting C-type lectin.  相似文献   
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The overarching goal of this research project is to develop a set of theoretical and empirical based design principles to support student engagement in flipped mathematics learning. We used a design-based research approach in which a series of studies was conducted in a secondary school. First, an analysis of practical problems was performed via exploratory studies (Studies 1A and 1B), randomized experiments (Studies 2A and 2B), and a literature review (Study 3). Second, a basic flipped lesson prototype was developed based on our empirical findings and relevant theoretical work of student engagement and self-determination theory. Third, we refined and evaluated our practice with two empirical studies (Studies 4 and 5). Finally, we reflected on each stage of our research project to produce a set of design principles for future practice. This study thus contributes to our knowledge of methods to support student engagement in flipped mathematics learning.  相似文献   
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Enterococci are ubiquitous lactic acid bacteria commonly associated with the human digestive tract as commensal organisms. Additionally, these organisms have a long history of use in foods improving flavor as well as providing protective mechanisms as either a probiotic or antimicrobial additive. However, Enterococcus faecalis accounts for up to 10% of all nosocomial infections of the bloodstream, wounds, urinary tract and heart. Knowledge about the regulation of virulence factors is limited and the involvement of environmental signals contributing to E. faecalis pathogenicity is poorly documented. In this study, two clinical E. faecalis isolates, TMW 2.63 and OG1RF, as well as one food isolate, TMW 2.629, were subjected to six sub-lethal food- and host-related stresses including 6.8% NaCl, 200 ppm nitrite, 51 °C, 80 MPa, pH 4.1 and 0.08% bile salts (cholic acid:chenodeoxycholic acid 1:1), respectively, reducing their growth rate to 10%. Relative gene expression of 15 stress and virulence-associated genes including dnaK, groEL, ctsR, clpPBCEX, gls24, efaAfs, ace, fsrB, gelE, sprE and cylB, was quantified by using real time PCR and Lightcycler® technology (reference conditions: BHI broth, 37 °C, pH = 7.4). Apart from strain-dependent differences, sub-lethal environmental stress was capable of provoking significant alterations in the expression of virulence-associated genes in E. faecalis from clinical as well as food origins of isolation. These results help to avoid preconditioning enterococci in food production processes and to understand the complex mechanisms in E. faecalis' switch to pathogenicity.  相似文献   
10.
A study of the interaction of commercial black ink with a UV‐curable polyurethane acrylate (PUA) is presented. Diffusivity and solubility in PUA cured using different UV dosages, and subjected to different post‐UV curing conditions, were studied, as was the swelling produced by such sorption. Experiments were also conducted using water, to serve as a benchmark and compare with the effect of ink. The percentage ink absorption was found to decrease with higher degree of cure. In addition, through desorption measurements, ink induced swelling of PUA processed under different conditions was determined. The degree of swelling per unit solvent uptake was observed to increase with the degree of cure. PUA was determined to be more prone to moisture rather than solvent uptake. However, the coefficient of moisture expansion (CME) was found to be ~ 35% lower than the coefficient of ink expansion (CIE) for a fully cured PUA. © 2006 Wiley Periodicals, Inc. JAppl PolymSci 103: 1985–1991, 2007  相似文献   
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