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Colour has the potential to elicit emotions or behaviors, yet there is little research in which colour treatments in website design are systematically tested. Little is known about how colour affects trust or satisfaction on the part of the viewer. Although the Internet is increasingly global, few systematic studies have been undertaken in which the impact of colour on culturally diverse viewers is investigated in website design. In this research three website colour treatments are tested across three culturally distinct viewer groups for their impact on user trust, satisfaction, and e-loyalty. To gather data, a rich multi-method approach is used including eye-tracking, a survey, and interviews. Results reveal that website colour appeal is a significant determinant for website trust and satisfaction with differences noted across cultures. The findings have practical value for web marketers and interface designers concerning effective colour use in website development.  相似文献   
53.
The mass loadings of quinones and their ability to generate reactive oxygen species (ROS) were investigated in total suspended particulate samples collected in Fresno, CA, over a 12-month period. Particles were collected on Teflon filters and were analyzed for the presence of 12 quinones containing one to four aromatic rings by gas chromatography with mass spectrometry. Measured levels are generally greater than mass loadings reported at other locations. The mass loadings were highest during winter months and were strongly anticorrelated with temperature. ROS generation was investigated by measuring the rate of hydrogen peroxide production from the reaction of laboratory standards and ambient samples with dithiothreitol (DTT). ROS generation from ambient samples shows a strong positive correlation with the mass loadings of the three most reactive quinones and may account for all of the ROS formed in the DTT test.  相似文献   
54.
Bacterial reduction of arsenic(V) and iron(III) oxides influences the redox cycling and partitioning of arsenic (As) between solid and aqueous phases in sediment-porewater systems. Two types of anaerobic bacterial incubations were designed to probe the relative order of As(V) and Fe(III) oxide reduction and to measure the effect of adsorbed As species on the rate of iron reduction, using hydrous ferric oxide (HFO) as the iron substrate. In one set of experiments, HFO was pre-equilibrated with As(V) and inoculated with fresh sediment from Haiwee Reservoir (Olancha, CA), an As-impacted field site. The second set of incubations consisted of HFO (without As) and As(III)- and As(V)- equilibrated HFO incubated with Shewanella sp. ANA-3 wild-type (WT) and ANA-3deltaarrA, a mutant unable to produce the respiratory As(V) reductase. Of the two pathways for microbial As(V) reduction (respiration and detoxification), the respiratory pathway was dominant under these experimental conditions. In addition, As(III) adsorbed onto the surface of HFO enhanced the rate of microbial Fe(III) reduction. In the sediment and ANA-3 incubations, As(V) was reduced simultaneously or prior to Fe(III), consistent with thermodynamic calculations based on the chemical conditions of the ANA-3 WT incubations.  相似文献   
55.
The absence of longitudinal data about correlates of physical activity during adolescence has hindered the identification of key mediator variables that can be targeted by interventions. Building on the authors' previous report of a cross-sectional analysis, this study compared barriers self-efficacy and perceived behavioral control as predictors of change in 2 levels of physical activity across a 1-year period among a sample of Black and White adolescent girls (N = 1,038). Self-efficacy did not predict change in either moderate or vigorous physical activity. In contrast, perceived behavioral control exhibited a longitudinal, independent relationship with change in vigorous physical activity. The authors concluded that perceived behavioral control is an independent predictor of change in vigorous physical activity levels across a 1-year period among a sample of Black and White adolescent girls and warrants study as a potential mediator variable in interventions designed to increase or maintain physical activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Semi-Automated Extraction of Rivers from Digital Imagery   总被引:3,自引:0,他引:3  
The manual production of vector maps from digital imagery can be a time consuming and costly process. Developing tools to automate this task for specific features, such as roads, has become an important research topic. The purpose of this paper was to present a technique for the semi-automatic extraction of multiple pixel width river features appearing in high resolution satellite imagery. This was accomplished using a two stage, multi-resolution procedure. Initial river extraction was performed on low resolution (SPOT multi-spectral, 20 m) imagery. The results from this low resolution extraction were then refined on higher resolution (KFA1000, panchromatic, 5 m) imagery to produce a detailed outline of the channel banks. To perform low resolution extraction a cost surface was generated to represent the combined local evidence of the presence of a river feature. The local evidence of a river was evaluated based on the results of a number of simple operators. Then, with user specified start and end points for the network, rivers were extracted by performing a least cost path search across this surface using the A* algorithm. The low resolution results were transferred to the high resolution imagery as closed contours which provided an estimate of the channel banks. These contours were then fit to the channel banks using the dynamic contours (or snakes) technique.  相似文献   
58.
The effects of tides, bioturbating organisms, and periods of anoxia on metal fluxes from contaminated harbor sediments in a shallow tidal estuarine bay were studied, together with capping technology options for the containment of metal contaminants. Zinc fluxes from the sediments were high, ranging from 10 to 89 mg of Zn m(-2) day(-1). In the absence of capping, experiments in corer-reactors showed that simulated tidal processes increased zinc fluxes 5-fold. Fluxes were also greater in the presence of sediment-dwelling organisms. If organisms were removed, and recolonizing organisms later added, their bioturbation activities initially lowered zinc fluxes, but fluxes gradually reached steady state at the higher levels seen previously. Capping materials physically isolate contaminated sediments, provide a binding substrate for metals released from the sediment and importantly create an anoxic environment below the cap, which stimulates the formation of insoluble metal sulfides. Clean sediment (5 mm) was the most effective capping material in reducing zinc fluxes. Zeolite/sand mixtures (10 mm) also greatly reduced these fluxes, but significant breakthrough of zinc occurred after 2 weeks. Sand (20 mm) was not effective. The presence of organisms disturbed capping materials and increased zinc fluxes. Installed capping materials should have depths of >30 cm to minimize organisms burrowing to contaminated sediments beneath.  相似文献   
59.
Anger and aggression among drivers in three European countries   总被引:3,自引:0,他引:3  
Recent reports of 'road rage' in the British media give the impression that driver aggression is escalating. In order to understand this phenomenon we need to know what it is about driving that provokes motorists to feel anger and then to go on to express that anger in the form of aggression. A postal questionnaire survey of more than 2500 drivers was carried out in three European countries: Britain, Finland and the Netherlands. The study had three main aims: (a) to discover how angry, if at all, a range of situations on the road make drivers, (b) to find out how many drivers are likely to react aggressively to those situations, and (c) to investigate individual and/or cultural differences in terms of anger and/or aggressive responses among motorists. Results indicate that the same types of behaviour provoke anger and aggression in all three countries, and that traffic density may play a role.  相似文献   
60.
A new reference material (RM), RM 8504, has been prepared for use as a diluent oil with Aroclors in transformer oil Standard Reference Materials (SRMs) 3075 to 3080 and SRM 3090 when developing and validating methods for the determination of polychlorinated biphenyls (PCBs) as Aroclors in transformer oil or similar matrices. SRMs 3075-3080 and SRM 3090 consist of individual Aroclors in the same transformer oil that was used to prepare RM 8504. A unit of RM 8504 consists of one bottle containing approximately 100 mL of transformer oil. No additional constituents have been added to the oil.  相似文献   
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