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81.
In this paper we explore the relationship between monthly random breath testing (RBT) rates (per 1000 licensed drivers) and alcohol-related traffic crash (ARTC) rates over time, across two Australian states: Queensland and Western Australia. We analyse the RBT, ARTC and licensed driver rates across 12 years; however, due to administrative restrictions, we model ARTC rates against RBT rates for the period July 2004 to June 2009.  相似文献   
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Superstorm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to eight genera: Penicillium (11 species), Fusarium (four species), Aspergillus (three species), Trichoderma (two species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis. Then, we used a Drosophila larval assay to assess possible toxicity of volatile organic compounds (VOCs) emitted by these molds. When cultured in a shared atmosphere with growing cultures of molds isolated after Hurricane Sandy, larval toxicity ranged from 15 to 80%. VOCs from Aspergillus niger 129B were the most toxic yielding 80% mortality to Drosophila after 12 days. The VOCs from Trichoderma longibrachiatum 117, Mucor racemosus 138a, and Metarhizium anisopliae 124 were relatively non‐toxigenic. A preliminary analysis of VOCs was conducted using solid‐phase microextraction‐gas chromatography‐mass spectrometry from two of the most toxic, two of the least toxic, and two species of intermediate toxicity. The more toxic molds produced higher concentrations of 1‐octen‐3‐ol, 3‐octanone, 3‐octanol, 2‐octen‐1‐ol, and 2‐nonanone; while the less toxic molds produced more 3‐methyl‐1‐butanol and 2‐methyl‐1‐propanol, or an overall lower amount of volatiles. Our data support the hypothesis that at certain concentrations, some VOCs emitted by indoor molds are toxigenic.  相似文献   
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The South Pole Imaging Fabry-Perot Interferometer (SPIFI) is the first instrument of its kind-a direct-detection imaging spectrometer for astronomy in the submillimeter band. SPIFI's focal plane is a square array of 25 silicon bolometers cooled to 60 mK; the spectrometer consists of two cryogenic scanning Fabry-Perot interferometers in series with a 60-mK bandpass filter. The instrument operates in the short submillimeter windows (350 and 450 microm) available from the ground, with spectral resolving power selectable between 500 and 10,000. At present, SPIFI's sensitivity is within a factor of 1.5-3 of the photon background limit, comparable with the best heterodyne spectrometers. The instrument's large bandwidth and mapping capability provide substantial advantages for specific astrophysical projects, including deep extragalactic observations. We present the motivation for and design of SPIFI and its operational characteristics on the telescope.  相似文献   
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A novel microstructured fibre has been created for use in an optical interconnection system. The fibre has low crosstalk with a high density of cores corresponding to 1150 channels/mm/sup 2/. A repeating pseudorandom binary sequence has been used to demonstrate a four-channel transmit/receive system using vertical cavity surface emitting lasers as both emitters and detectors.  相似文献   
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A solid-phase extraction (SPE) method employing silver nitrate impregnated silica has been developed and evaluated for the separation of defined aliphatic and aromatic hydrocarbons from crude oils. The versatility of the SPE method is demonstrated using a light crude oil from the North Sea and a heavy crude oil from Orcutt field (Monterey, California, U.S.A.). The coefficients of variation for a number of geochemical parameters measured on both aliphatic and aromatic hydrocarbons were excellent. The separation efficiency of SPE is demonstrated using quantification of monoaromatic steroid hydrocarbons which are notoriously difficult to efficiently sequester into the aromatic hydrocarbon fraction using traditional liquid chromatographic procedure. The selectivity and efficiency of the SPE technique is comparable with that of silica gel TLC. However, losses of volatile compounds such as naphthalene are limited during SPE since the sample remains in solvent. We conclude that solid-phase extraction affords rapid sample turnover suitable for processing large sample numbers with high reproducibility.  相似文献   
90.
Béland MC  Bennett JM 《Applied optics》2000,39(16):2719-2726
A critical factor that affects the appearance of printed paper surfaces is gloss uniformity, which is usually assessed visually. To relate gloss uniformity to nonvisual quantities, we first visually identified areas of either high or low gloss on the same sample for two different types of paper. We then measured the roughness and the reflectance of these areas. Microroughness was measured with an atomic-force microscope, and roughness was measured over a larger area with a confocal laser scanning microscope. The local reflectance of the high-gloss and the low-gloss areas was obtained from images taken with a gloss-imaging instrument and compared with the roughness of each area. This correlation is nonlinear, and roughness is insufficient to predict the local reflectance. Light-scattering measurements were made in the specular direction to map the gloss uniformity over larger areas than was possible with the gloss-imaging instrument. These maps were used to show the possibility of using both the spatial frequency and the fan filters, which together form a set of cortex filters, to analyze the variation of the gloss about the mean value and its spatial distribution on the surface in terms of spatial frequency and azimuthal orientation.  相似文献   
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