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81.
Studies show that teenage drivers are at a higher risk for crashes. Opportunities to engage in technology and non-technology based distractions appear to be a particular concern among this age group. An ordered logit model was developed to predict the likelihood of a severe injury for these drivers and their passenger using a national crash database (the 2003, U.S. DOT-General Estimate System [GES]). As one would expect, speeding substantially increases the likelihood of severe injuries for teenage drivers and their passengers. The results of the analysis also reveal that teenage drivers have an increased likelihood of more severe injuries if distracted by a cell phone or by passengers than if the source of distraction was related to in-vehicle devices or if the driver was inattentive. Additionally, passengers of teenage drivers are more likely to sustain severe injuries when their driver is distracted by devices or passengers than with a non-distracted or inattentive driver. This supports the previous literature on teenage drivers and extends our understanding of injuries for this age group related to distraction-related crashes. 相似文献
82.
Giuntini F Dumoulin F Daly R Ahsen V Scanlan EM Lavado AS Aylott JW Rosser GA Beeby A Boyle RW 《Nanoscale》2012,4(6):2034-2045
Polyacrylamide nanoparticles bearing two orthogonal reactive functionalities were prepared by reverse microemulsion polymerisation. Water-soluble photosensitisers and peptide or carbohydrate moieties were sequentially attached to the new nanospecies by orthogonal conjugations based on copper-catalysed azide-alkyne cycloaddition and isothiocyanate chemistry. 相似文献
83.
The cigarette usually carries in its smoke significant doses of carcinogenic tobacco specific nitrosamines (TSNAs), which have been implicated as causes of oral, lung, oesophageal, and pancreatic cancer. However, there is substantial variation in nitrosamine content of the smoke of modern cigarettes. This variation is both unacceptable and unnecessary, as TSNAs can be readily removed during the manufacturing process. Removing a known carcinogen needs no justification, even though proof of benefit may not be forthcoming for decades. 相似文献
84.
Two new methods for synthesizing nanostructured HfO2 have been developed. The first method entails exposing HfTe2 powders to air. This simple process resulted in the formation of nanometer scale crystallites of HfO2. The second method involved a two-step heating process by which macroscopic, freestanding nanosheets of HfO2 were formed as a byproduct during the synthesis of HfTe2. These highly two-dimensional sheets had side lengths measuring up to several millimeters and were stable enough to be manipulated
with tweezers and other instruments. The thickness of the sheets ranged from a few to a few hundred nanometers. The thinnest
sheets appeared transparent when viewed in a scanning electron microscope. It was found that the presence of Mn enhanced the
formation of HfO2 by exposure to ambient conditions and was necessary for the formation of the large scale nanosheets. These results present
new routes to create freestanding nanostructured hafnium dioxide. 相似文献
85.
A soft radio architecture for reconfigurable platforms 总被引:7,自引:0,他引:7
While many soft/software radio architectures have been suggested and implemented, there remains a lack of a formal design methodology that can be used to design and implement these radios. This article presents a unified architecture for the design of soft radios on a reconfigurable platform called the layered radio architecture. The layered architecture makes it possible to incorporate all of the features of a software radio while minimizing complexity issues. The layered architecture also enables a methodology for incorporating changes and updates into the system. An example implementation of the layered architecture on actual hardware is presented 相似文献
86.
PURPOSE: To visualize the structure and determine the continuity of lipid membranes in lens fiber cells (LFCs) from human aged normal and cataractous lenses. METHODS: Thick sections from human nuclear cataracts and aged normal lenses were stained with the lipophilic probe DiI, and then analyzed by confocal microscopy. Staining patterns of membranes were observed in individual optical sections or three-dimensional projections of z-series taken in longitudinal section and cross-section of LFCs from different regions within the lens nucleus. RESULTS: DiI bound to and delineated the plasma membrane of LFCs from all regions of the lens nucleus. Three-dimensional projections of z-series from aged normal and cataractous lenses suggested that some of the stained lipid membranes were not continuous with LFC plasma membrane of cataractous lenses. CONCLUSIONS: The results obtained using these methods demonstrated that lipid membranes, discontinuous with the plasma membrane of LFCs, were indicative of a novel process occurring predominately in cataractous human lenses. 相似文献
87.
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89.
SM Farrington C Cunningham SM Boyle AH Wyllie MG Dunlop 《Canadian Metallurgical Quarterly》1996,12(8):1803-1808
Loss of heterozygosity (LOH) of markers at chromosome 8p is frequently noted in many different tumour types, including colorectal cancer. Numerous investigations indicate the presence of more than tumour suppressor gene (TSG) located on 8p. In this study, we describe a detailed LOH map in colorectal cancer and relate this to physical mapping data from reduced radiation 8p hybrids, yeast artificial chromosome (YAC) co-localisation of markers and fluorescence in situ hybridisation data. These data indicate the presence of two regions harbouring putative TSG's between the polymorphic markers for the LPL gene-D8S298 (approximately 4 Mb) and the markers D8S136-D8S137 (approximately 8 Mb). Yeast Artificial Chromosomes (YAC) have been isolated from these regions of interest to aid the localisation of the putative TSG's. 相似文献
90.