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91.
92.
Welte John W.; Barnes Grace M.; Tidwell Marie-Cecile O.; Hoffman Joseph H. 《Canadian Metallurgical Quarterly》2009,23(1):105
A random telephone survey was conducted with 2,274 United States residents aged 14 to 21. Analyses were performed to assess the relationship between the specific gambling games played and the extent of problem gambling symptoms. The forms of gambling that were most associated with gambling problems were card games, casino gambling, “other” gambling on routine activities, and betting on games of skill such as basketball, pool, or golf. The form of gambling that made the largest contribution to gambling problems per 14 days of play was casino gambling. The hypothesis that rapid forms of gambling, such as slot machines, would be the most problematic forms of gambling was not upheld. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Creating linguistic summaries of data has been a goal of the artificial and computational intelligence communities for many years. Summaries of written text have garnered the most attention. More recently, creating summaries of imagery and other sensed data has become important as a means of compressing large amounts of data and communicating with humans. In this paper, we consider the question of comparing sets of summaries generated from sensed data. In an earlier work, we developed a metric between individual protoform‐based summaries; and here, as a next step, we propose aggregation methods to fuse these individual distances. We provide a case study from eldercare where the goal is to compare different nighttime patterns for change detection. © 2012 Wiley Periodicals, Inc. 相似文献
94.
Band-gap tuning of pendant polymers for organic light-emitting devices and photovoltaic applications
Akhil Gupta Scott E. Watkins Andrew D. Scully Th. Birendra Singh Gerard J. Wilson Lynn J. Rozanski Richard A. Evans 《Synthetic Metals》2011,161(9-10):856-863
The preparation of a series of novel polymers comprising pendant electro-active “push–pull” chromophores and their performance in solution-processed organic electronic devices is described. The design of the electro-active pendant chromophores was based on the well-known motif of cyano-substituted poly(p-phenylenevinylene). Optical band-gap engineering within this series of polymers was achieved by varying the conjugation length and the electron donor/acceptor functionalities of the pendant chromophores. The introduction of a cyanoimine group into the electro-active pendant module resulted in a marked narrowing of the optical band-gap compared with the other electro-active pendant chromophores investigated in this work. Bulk heterojunction solar cell devices comprising these polymers were prepared by solution processing blends of each polymer with [6,6]-phenyl-C61-butyric acid methyl ester, and their performance was evaluated by measuring power conversion efficiencies. The best-performing solar cell in this series exhibited a power conversion efficiency of 0.29% and a maximum incident photon-to-current conversion efficiency of 22% and was produced using the polymer in which the electro-active chromophore comprised the cyanoimine group. 相似文献
95.
Valmikinathan CM Hoffman J Yu X 《Materials science & engineering. C, Materials for biological applications》2011,31(1):22-29
Over the last decade tissue engineering has emerged as a powerful alternative to regenerate lost tissues owing to trauma or tumor. Evidence shows that Schwann cell containing scaffolds have improved performance in vivo as compared to scaffolds that depend on cellularization post implantation. However, owing to limited supply of cells from the patients themselves, several approaches have been taken to enhance cell proliferation rates to produce complete and uniform cellularization of scaffolds. The most common approach is the application of a bioreactor to enhance cell proliferation rate and therefore reduce the time needed to obtain sufficiently significant number of glial cells, prior to implantation.In this study, we show the application of a rotating wall bioreactor system for studying Schwann cell proliferation on nanofibrous spiral shaped scaffolds, prepared by solvent casting and salt leaching techniques. The scaffolds were fabricated from polycaprolactone (PCL), which has ideal mechanical properties and upon degradation does not produce acidic byproducts. The spiral scaffolds were coated with aligned or random nanofibers, produced by electrospinning, to provide a substrate that mimics the native extracellular matrix and the essential contact guidance cues.At the 4 day time point, an enhanced rate of cell proliferation was observed on the open structured nanofibrous spiral scaffolds in a rotating wall bioreactor, as compared to static culture conditions. However, the cell proliferation rate on the other contemporary scaffolds architectures such as the tubular and cylindrical scaffolds show reduced cell proliferation in the bioreactor as compared to static conditions, at the same time point. Moreover, the rotating wall bioreactor does not alter the orientation or the phenotype of the Schwann cells on the aligned nanofiber containing scaffolds, wherein, the cells remain aligned along the length of the scaffolds. Therefore, these open structured spiral scaffolds pre-cultured with Schwann cells, in bioreactors could potentially shorten the time needed for grafts for peripheral nerve regeneration. 相似文献
96.
Willmott Lynn; Harris Peter; Gellaitry Grace; Cooper Vanessa; Horne Rob 《Canadian Metallurgical Quarterly》2011,30(5):642
Objective: To assess the effects of expressive writing on health care utilization, clinical variables and subjective quality of life following first myocardial infarction (MI). Methods: One-hundred and seventy-nine first MI patients were randomized to Intervention (N = 88) or Control (N = 91) groups. The intervention group wrote about their thoughts and feelings in relation to having had an MI. Controls wrote in a neutral way about daily activities. The main outcome measures were health care utilization, physical status and subjective quality of life (QOL), assessed after one, two, and five months. Results: One-hundred and fifty-six (87%) completed the study. Five months post-intervention, the intervention group had significantly fewer recorded medical appointments compared to controls. The number of prescribed medicines decreased over time within the intervention group but increased within the control group. The intervention group attended significantly more rehabilitation sessions, reported fewer cardiac related symptoms and had lower diastolic blood pressure five months post-intervention. There was no significant group by time interaction on reported physical health. The group by time interaction on reported mental health approached significance, those in the intervention group reporting greater improvement. Conclusion: Expressive writing may be a beneficial strategy which could be incorporated into rehabilitation interventions to help individuals adjust after first MI. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
97.
Delaunay P.-Y. Binh Minh Nguyen Hoffman D. Huang E.K.-W. Razeghi M. 《Quantum Electronics, IEEE Journal of》2009,45(2):157-162
The recent introduction of a M-structure design improved both the dark current and R0 A performances of type-II InAs-GaSb photodiodes. A focal plane array fabricated with this design was characterized at 81 K. The dark current of individual pixels was measured between 1.1 and 1.6 nA, 7 times lower than previous superlattice FPAs. This led to a higher dynamic range and longer integration times. The quantum efficiency of detectors without antireflective coating was 74%. The noise equivalent temperature difference reached 23 mK, limited only by the performance of the testing system and the read out integrated circuit. Background limited performances were demonstrated at 81 K for a 300 K background. 相似文献
98.
Carolyn M. Nyberg Jeffrey S. Thompson Ye Zhuang John H. Pavlish Lynn Brickett Sara Pletcher 《Fuel Processing Technology》2009
During the past several years, and particularly since the Clean Air Mercury Rule (CAMR) was promulgated in June of 2005, the electric utility industry, product vendors, and the research community have been working diligently to develop and test Hg control strategies for a variety of coal types and plant configurations. Some of these strategies include sorbent injection and chemical additives designed to increase mercury capture efficiency in particulate control devices. These strategies have the potential to impact the fate of other inorganic hazardous air pollutants (HAPs), which typically include As, Be, Cd, Cr, Co, Mn, Ni, Pb, Se, and Sb. To evaluate this impact, flue gas samples using EPA Method 29, along with representative coal and ash samples, were collected during recent pilot-scale and field test projects that were evaluating Hg control technologies. These test programs included a range of fuel types with varying trace element concentrations, along with different combustion systems and particulate control devices. The results show that the majority of the trace element HAPs are associated with the particulate matter in the flue gas, except for Se. However, for five of the six projects, Se partitioning was shifted to the particulate phase and total emissions reduced when Hg control technologies were applied. 相似文献
99.
This study compares the effects of day- and night cropping on the quality of gemsbok meat. Day-cropped animals had higher behavioural scores and cortisol levels (behavioural score: 3.5 ± 0.423; cortisol: 136.88 ± 2.731 nmol/L) than night-cropped animals (behavioural score: 2.1 ± 0.378; cortisol: 64.1 ± 1.633 nmol/L) while night-cropped animals had a higher mean pHu (5.54 ± 0.013) than day-cropped animals (5.49 ± 0.014). The exponential decay model, y = a + b−ct, fitted to the pH data indicated a difference in constant a only (day = 5.45 ± 0.006; night = 5.51 ± 0.006). Night-cropped animals produced meat that was darker in colour. The results indicate that day cropping may have elicited more ante-mortem stress although this did not necessarily affect the meat quality adversely, however due to the limitation of sample size, the data may be skewed by outliers and should thus be interpreted with caution. 相似文献
100.
Christos S. Christoforou Lynn G. Salmon Glen R. Cass 《Aerosol science and technology》2013,47(6):530-544
Air exchange between interior spaces and the outdoor atmosphere can occur due to a variety of processes, including wind-driven flows and natural convectiondriven flows. As air is exchanged with the outdoors, airborne particles can be brought inside. Depending on the use of the indoor space, the presence of particles in indoor air could be a nuisance to the occupants or could be damaging to materials kept indoors. While one obvious solution to such problems is to install a mechanical air filtration system, that is not always practical. In particular, the character of some historical houses and some archaeological sites would be degraded by the presence of a mechanical air distribution system, and in some parts of the world the reliable electrical power supply needed for such a filtration system may not be available. In the present paper we consider principles for the design of passive filtration systems in which air motion through the filter material is induced by a natural convection flow rather than by a mechanical fan. A fluid mechanical model first is described for predicting the air flow through an interior space that acts as a thermal siphon. The effect of placing filter material in the path of such air flows is examined next. The indoor-outdoor air quality model of Nazaroff and Cass (1989a) is matched to the natural convection air exchange model, and calculations are performed to determine the relationship between the outdoor particle size distribution and indoor particle size distributions and particle deposition rates given a passive filtration system. Example calculations are worked for the case of a passive particle filtration system that could be installed to protect the interior of the Buddhist cave temples at Yungang, China. These are a collection of manmade cave temples dating from the 5th century AD, now situated in the middle of one of China's largest coal-mining regions with its accompanying air pollution problems. 相似文献