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1.
The well-characterized Alberta Sweet Mixed Blend oil and several other oils which are commonly transported in Canada were physically weathered and then incubated with a defined microbial inoculum. The purpose was to produce quantitative data on oil components and component groups which are more susceptible or resistant to biodegradation, and to determine how oils rank in relation to each other in terms of biodegradation potential. The biodegraded oils were characterized by quantitative determination of changes in important hydrocarbon groups including the total petroleum hydrocarbons, total saturates and aromatics, and also by quantitation of more than 100 individual target aliphatic, aromatic and biomarker components. The study reveals a pattern of distinct oil composition changes due to biodegradation, which is significantly different from the pattern due to physical or short-term weathering. It is important to be able to distinguish between these two forms of loss, so that loss due to weathering is not interpreted as loss due to biodegradation in the laboratory or in the field. Based on these findings, the oil composition changes due to biodegradation can be readily differentiated from those due to physical weathering. To rank the tested oils with respect to biodegradability, losses in total petroleum hydrocarbons and aromatics were used to calculate biodegradation potential indices, employing equations proposed by Environment Canada and the US National Oceanic and Atmospheric Administration. The different methods produced very similar biodegradation trends, confirming that patterns of oil biodegradability do exist.  相似文献   
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ABSTRACT

Incorporating digital gaming into education is an increasingly popular topic in academia. Educators’ views of digital gaming (e.g., computer, video, and online games) have shifted from categorizing these games as an entertaining, yet pedagogically void activity to a promising medium that engages students in the learning process. With over 70% of college students enthusiastically playing digital games, educators are tapping into digital gaming as an effective means to teach millennials problem solving and communication skills. This article investigates gamer characteristics, motivational and engaging aspects of digital games, and the parallels between gaming and the information retrieval process. The authors build on this information to present approaches to incorporate digital gaming techniques into the library classroom since it is not feasible for all libraries to create instructional digital games.  相似文献   
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In the framework of online object retrieval with learning, we address the problem of graph matching using kernel functions. An image is represented by a graph of regions where the edges represent the spatial relationships. Kernels on graphs are built from kernel on walks in the graph. This paper firstly proposes new kernels on graphs and on walks, which are very efficient for graphs of regions. Secondly we propose fast solutions for exact or approximate computation of these kernels. Thirdly we show results for the retrieval of images containing a specific object with the help of very few examples and counter-examples in the framework of an active retrieval scheme.  相似文献   
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Hydrogen gas physisorption in two distinct dinuclear Pt(II) metallacycles was investigated with 2H nuclear magnetic resonance (NMR) spectroscopy. Hydrogen adsorption isotherm data and 2H NMR spectroscopy indicated that hydrogen storage occurs via condensation within the cavities of one of the macrocycles and at the interstitial sites in the other. In addition, this study further supports the notion that heat of adsorption and pore size play critical roles in hydrogen storage.  相似文献   
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In this article we describe results froman experiment of user interaction with autonomous , human - like ( humanoid ) conversational agents . We hypothesize that for embodied conversational agents , nonverbal behaviors related to the process of conversation , what we call envelope feedback, is much more important than other feedback , such as emotional expression . We test this hypothesis by having subjects interact with three autonomous agents , all capable of full - duplex multimodal interaction: able to generate and recognize speech , intonation , facial displays , and gesture . Each agent , however , gave a different kind of feedback: ( 1 ) content - related only , ( 2 ) content + envelope feedback , and ( 3 ) content + emotional . Content-related feedback includes answering questions and executing commands; envelope feedback includes behaviors such as gaze , manual beat gesture , and head movements; emotional feedback includes smiles and looks of puzzlement . Subjects' evaluations of the systemwere collected with a questionnaire , and videotapes of their speech patterns and behaviors were scored according to how often the users repeated themselves , how often they hesitated , and how often they got frustrated . The results confirmour hypothesis that envelope feedback is more important in interaction than emotional feedback and that envelope feedback plays a crucial role in supporting the process of dialog . A secondary result fromthis study shows that users give our multimodal conversational humanoids very high ratings of lifelikeness and fluidity of interaction when the agents are capable of giving such feedback .  相似文献   
9.
The PRUTEEN plant represents a major innovation in the green field of biotechnology. The 50 000-t/a-plant was sanctioned in 1976 as a £40-million-project and built by contractors John Brown. The 600 t fermenter vessel in particular was an impressive piece of engineering: fabricated in Dunkirk, it was transported to the Billingham site in one piece. This paper illustrates why, given the risks of innovation on such a scale, ICI chose a novel fermentation process. Particular reference is made to the pressure cycle fermenter and how it works, and to the product recovery stage. The approach to sterile engineering, which is crucial to the effective operation of the fermentation process, is also discussed. Faced with unique technical challenges, ICI pioneered practical solutions, and, through operational experience, has arrived at the point today of being able to license the process.  相似文献   
10.
Drivers are not always aware that they are becoming impaired as a result of sleepiness. Using specific symptoms of sleepiness might assist with recognition of drowsiness related impairment and help drivers judge whether they are safe to drive a vehicle, however this has not been evaluated. In this study, 20 healthy volunteer professional drivers completed two randomized sessions in the laboratory – one under 24 h of acute sleep deprivation, and one with alcohol. The Psychomotor Vigilance Task (PVT) and a 30 min simulated driving task (AusEdTM) were performed every 3–4 h in the sleep deprivation session, and at a BAC of 0.00% and 0.05% in the alcohol session, while electroencephalography (EEG) and eye movements were recorded. After each test session, drivers completed the Karolinska Sleepiness Scale (KSS) and the Sleepiness Symptoms Questionnaire (SSQ), which includes eight specific sleepiness and driving performance symptoms. A second baseline session was completed on a separate day by the professional drivers and in an additional 20 non-professional drivers for test–retest reliability. There was moderate test–retest agreement on the SSQ (r = 0.59). Significant correlations were identified between individual sleepiness symptoms and the KSS score (r values 0.50–0.74, p < 0.01 for all symptoms). The frequency of all SSQ items increased during sleep deprivation (χ2 values of 28.4–80.2, p < 0.01 for all symptoms) and symptoms were related to increased subjective sleepiness and performance deterioration. The symptoms “struggling to keep your eyes open”, “difficulty maintaining correct speed”, “reactions were slow” and “head dropping down” were most closely related to increased alpha and theta activity on EEG (r values 0.49–0.59, p < 0.001) and “nodding off to sleep” and “struggling to keep your eyes open” were related to slow eye movements (r values 0.67 and 0.64, p < 0.001). Symptoms related to visual disturbance and impaired driving performance were most accurate at detecting severely impaired driving performance (AUC on ROC curve of 0.86–0.91 for detecting change in lateral lane position greater than the change at a BAC of 0.05%). Individual sleepiness symptoms are related to impairment during acute sleep deprivation and might be able to assist drivers in recognizing their own sleepiness and ability to drive safely.  相似文献   
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