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991.
Current civil engineering education should address the need to provide a broad vision, develop the higher-order skills of future civil engineers, enable them to adopt emerging technologies, and formulate innovative solutions to complex problems. This paper introduces relevant nanotechnology developments to convey the new vision and inspire creativity in civil engineering. It also presents a pedagogical framework for integrating nanotechnology education into a civil engineering curriculum and cultivating self-regulated learning and creativity skills for civil engineering students. The pedagogical framework includes the introduction of nanotechnology innovations and other relevant innovative technologies, and explicit instructions on cognitive strategies for facilitating and inspiring self-regulated learning and creativity. It is implemented with problem/project-based learning for a cocurricular project that requires self-regulated learning and creativity. This pedagogical framework provides a model for integrating emerging technology education and higher-order skill development into existing engineering curriculum. The outcomes from the implementation of the pedagogical framework are presented, and their further improvements are discussed. 相似文献
992.
Minjae Lee U. Hyeok Choi David Salas‐de la Cruz Anuj Mittal Karen I. Winey Ralph H. Colby Harry W. Gibson 《Advanced functional materials》2011,21(4):708-717
New bis(ω‐hydroxyalkyl)imidazolium and 1,2‐bis[N‐(ω‐hydroxyalkyl)imidazolium]ethane salts are synthesized and characterized; most of the salts are room temperature ionic liquids. These hydroxyl end‐functionalized ionic liquids are polymerized with diacid chlorides, yielding polyesters containing imidazolium cations embedded in the main chain. By X‐ray scattering, four polyesters are found to be semicrystalline at room temperature: mono‐imidazolium‐C11‐sebacate‐C6 ( 4e ), mono‐imidazolium‐C11‐sebacate‐C11 ( 4c ), bis(imidazolium)ethane‐C6‐sebacate‐C6 ( 5a ), and bis(imidazolium)ethane‐C11‐sebacate‐C11 ( 5c ), all with hexafluorophosphate counterions. The other imidazolium polyesters, including all those with bis(trifluoromethanesulfonyl)imide (TFSI?) counterions, are amorphous at room temperature. Room temperature ionic conductivities of the mono‐imidazolium polyesters (4 × 10?6 to 3 × 10?5 S cm?1) are higher than those of the corresponding bis‐imidazolium polyesters (4 × 10?9 to 8 × 10?6 S cm?1), even though the bis‐imidazolium polyesters have higher ion concentrations. Counterions affect ionic conduction significantly; all polymers with TFSI? counterions have higher ionic conductivities than the hexafluorophosphate analogs. Interestingly, the hexafluorophosphate polyester, 1,2‐bis(imidazolium)ethane‐C11‐sebacate‐C11 ( 5c ), displays almost 400‐fold higher room temperature ionic conductivity (1.6 × 10?6 S cm?1) than the 1,2‐bis(imidazolium)ethane‐C6‐sebacate‐C6 analog ( 5a , 4.3 × 10?9 S cm?1), attributable to the differences in the semicrystalline structure in 5c as compared to 5a . These results indicate that semicrystalline polymers may result in high ionic conductivity in a soft (low glass tranition temperature, Tg) amorphous phase and good mechanical properties of the crystalline phase. 相似文献
993.
Projective transformation is a mathematical correction (implemented in software) used in the remote imaging field to produce distortion-free images. We present the application of projective transformation to correct minor alignment and astigmatism distortions that are inherent in dispersive spectrographs. Patterned white-light images and neon emission spectra were used to produce registration points for the transformation. Raman transects collected on microscopy and fiber-optic systems were corrected using established methods and compared with the same transects corrected using the projective transformation. Even minor distortions have a significant effect on reproducibility and apparent fluorescence background complexity. Simulated Raman spectra were used to optimize the projective transformation algorithm. We demonstrate that the projective transformation reduced the apparent fluorescent background complexity and improved reproducibility of measured parameters of Raman spectra. Distortion correction using a projective transformation provides a major advantage in reducing the background fluorescence complexity even in instrumentation where slit-image distortions and camera rotation were minimized using manual or mechanical means. We expect these advantages should be readily applicable to other spectroscopic modalities using dispersive imaging spectrographs. 相似文献
994.
Gabaldon D Xu Z Sun Y Servilla KS Hartshorne MF Tzamaloukas AH 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(4):568-572
Bacteremia from central venous catheter (CVC) infection causes morbidity and mortality in patients on hemodialysis (HD). Diagnosis of the infection can be difficult and may require special imaging. A 70-year-old man with diabetic nephropathy was on HD for 11 months through a permanent CVC. Because of symptomatic osteoporosis, he had kyphoplasty in three lumbar vertebrae (L2, L3, L4) 6 months after starting HD. Severe back pain persisted after kyphoplasty. Throughout the HD period, the exit site of the CVC had a clean appearance, there was no fever, and blood leukocyte counts were normal. During the 11th month of HD, he complained of subjective fever at home. Blood count revealed normal leukocyte count with neutrophilic predominance and blood cultures grew methicillin-resistant Staphylococcus aureus (MRSA). Echocardiogram revealed no heart valve vegetations, but irregular thickening of the CVC wall. Fluorodeoxyglucose positron-emission tomography-computed tomography (FDG-PET-CT) revealed severe inflammation of the CVC wall and a picture consistent with osteomyelitis and severe destruction of the body of the 11th thoracic vertebra. He was treated with intravenous vancomycin and removal of the CVC, the wall of which was grossly inflamed and grew in culture MRSA. Three weeks later, he discontinued HD because of persistent severe back pain. CVC infection with bacteremia and remote infectious foci having grave sequelae can develop in HD patients with paucity of clinical manifestations. FDG-PET-CT is a useful imaging tool in establishing the presence and extent of both the CVC infection and remote metastatic infectious foci. 相似文献
995.
Berthing T Bonde S Sørensen CB Utko P Nygård J Martinez KL 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(5):640-647
Nanowires (NWs) are attracting more and more interest due to their potential cellular applications, such as delivery of compounds or sensing platforms. Arrays of vertical indium-arsenide (InAs) NWs are interfaced with human embryonic kidney cells and rat embryonic dorsal root ganglion neurons. A selection of critical cell functions and pathways are shown not to be impaired, including cell adhesion, membrane integrity, intracellular enzyme activity, DNA uptake, cytosolic and membrane protein expression, and the neuronal maturation pathway. The results demonstrate the low invasiveness of InAs NW arrays, which, combined with the unique physical properties of InAs, open up their potential for cellular investigations. 相似文献
996.
Karen Trapenberg Frick 《Journal of the American Planning Association. American Planning Association》2013,79(3):190-200
Problem, research strategy, and findings: The Tea Party's effects on local and regional planning efforts, given the movement's fierce support of property rights and equally fierce opposition to sustainability goals in regional planning efforts, have received little study. I wanted to understand how Tea Party and fellow property rights advocates became involved in regional planning efforts in the San Francisco Bay Area and Atlanta, GA, and how planners perceived and dealt with their objections and tactics. Interactions between the two groups were marked by philosophical differences over the role of government and the necessity and value of regional planning. However, these actors were also deeply divided on plan content and the authenticity of the public outreach process. Tea Party and property rights activists were not the only ones with substantive and procedural concerns about regional planning efforts; tactical -coalitions of unexpected allies emerged, aligning on plan viability, finance methods and funding, project costs, impacts, and process. My research shows that common ground can be negotiated between -opposing groups on matters of content and process. The concerns of the various stakeholders involved parallel questions often addressed by scholarly planning research, providing evidence of continuing challenges and flaws in planning. Takeaway for practice: The planning community should not dismiss the opposition of Tea Party and property rights advocates; these activists could catalyze new coalitions of opponents if planners do not attend to the substantive and procedural concerns of participants. 相似文献
997.
Recent research has considered whether a range of social and physical characteristics of residential neighbourhoods are important in explaining social and spatial inequalities in health. One strand of this research has investigated the role of neighbourhood access to retail provision of healthy and affordable food. In this national study we used Geographical Information Systems (GIS) to examine the association between food retail (supermarkets, convenience stores and fast food outlets) and licensed alcohol outlet locations, and an area measure of deprivation for urban neighbourhoods across New Zealand. We found that contrary to the international evidence, for all outlet types, access to a range of retail options tended to be better in more deprived neighbourhoods. The implications of this socio-spatial distribution of food and alcohol retailing in reducing health inequalities are discussed. 相似文献
998.
UNMIX and Positive Matrix Factorization (PMF) solutions to the Chemical Mass Balance (CMB) equations were applied to chemically speciated PM2.5 measurements from 23 sites in California's San Joaquin Valley to estimate source contributions. Six and seven factors were determined by UNMIX for the low_PM2.5 period (February to October) and high_PM2.5 period (November to January), respectively. PMF resolved eightfactors for each period that corresponded with the UNMIX factors in chemical profiles and time series. These factors are attributed to marine sea salt, fugitive dust, agriculture-dairy, cooking, secondary aerosol, motor vehicle, and residential wood combustion (RWC) emissions, with secondary aerosol and RWC accounting for over 70% of PM2.5 mass during the high_PM2.5 period. A zinc factor was only resolved by PMF. The contribution from motor vehicles was between 10 and 25% with higher percentages occurring in summer. The PMF model was further evaluated by examining (1) site-specific residuals between the measured and calculated concentrations, (2) comparability of motor vehicle and RWC factors against source profiles obtained from recent emission tests, (3) edges in bi-plots of key indicator species, and (4) spatiotemporal variations of the factors' strengths. These evaluations support the compliance with model assumptions and give a higher confidence level to source apportionment results for the high_PM2.5 period. 相似文献
999.
Sara R Jaeger Karen L Rossiter Karen Lau 《Journal of the science of food and agriculture》2005,85(3):480-488
To explore how consumers perceive novel and familiar fruit, repertory grid interviews were carried out with 60 New Zealand women. Participants described their perceptions of nine fruit varying in familiarity. The data analysis established a two‐dimensional stimuli space that separated samples with respect to familiarity and the amount of preparation required. Fruit that was familiar was characterised as being well liked, easily available in shops and by a number of different use situations. The primary association with novel fruit was that it was expensive. The participants could not readily think of use situations for fruit they were unfamiliar with. Consumers were separated into groups according to the trait of food neophobia, which pertains to an individual's stable propensity to approach or avoid novel foods. When comparing the most neophobic (n = 14; avoids novel foods) and most neophilic (n = 14; approaches novel foods), individuals perceptual differences were uncovered pertaining to which of the fruit were considered novel and to the suitability of some usage situations (cooking and for children). This finding contributed to the growing evidence of the relationship between food neophobia and consumers' everyday food‐related behaviour. Copyright © 2004 Society of Chemical Industry 相似文献
1000.