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Recent reports have indicated that digital PCR may be useful for the noninvasive detection of fetal aneuploidies by the analysis of cell-free DNA and RNA in maternal plasma or serum. In this review we provide an insight into the underlying technology and its previous application in the determination of the allelic frequencies of oncogenic alterations in cancer specimens. We also provide an indication of how this new technology may prove useful for the detection of fetal aneuploidies and single gene Mendelian disorders. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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The realisation of an opto-chemical ammonia sensor suitable for personal monitoring tasks is described, comprising a cyanine dye immobilised in a microporous glass thin film. The fabrication of sensor platforms incorporating embossed grating couplers provides a compact optical design with effective waveguiding characteristics, resulting in reversible ammonia sensitivity in the 5-100 ppm range in under 2 min. Cross-sensitivity of sensor response with water and other potential interferents is considered.  相似文献   
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ABSTRACT

High seas fisheries remain one of the least transparent global production practices. Distance from shore, coupled with the highly mobile nature of fish stocks, has put attention on new monitoring, control and surveillance technologies to collect spatially referenced data on the location of fishing vessels, gears and even fish stocks and eradicate illegal, unreported and unregulated fishing activity. Faced with their nascent implementation, research is yet to address how these technologies are reconfiguring the roles and responsibilities of public and private actors involved in fisheries management, including who collects and controls fisheries related information. In this paper, we compare three monitoring, control and surveillance technologies that are gaining traction in fisheries; the use of private fish attraction devices in oceanic tuna fisheries, unmanned public drones for marine surveillance and global satellite monitoring of fishing vessels. In doing so, we question how different configurations of actors are structuring flows of information and with what effect on sustainability performance of high seas fisheries. We also explore how these technologies configure new (and imagined) geographies of high seas fisheries which challenge existing modes of fisheries management.  相似文献   
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ABSTRACT: This paper suggests theoretical models to forecast the demand for recreational boats in a metropolitan area, and their expected usage in various regional water bodies and marinas. The models, which are similar to those used in transportation studies, are implemented using statistical regression analysis and can be easily applied to a wide range of case studies. The models have been used to forecast demand for boats by type and size in the Cleveland S.M.S.A. The proportion of boats attracted to boating facilities on Lake Erie has been calculated. This study is significant in suggesting a theoretically sound methodology to project facilities required for recreational boats.  相似文献   
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This paper describes the results of a study of hydrologic factors affecting floods from humid region in northeastern Ohio. Statistical multiple correlation analysis was used to relate floods to hydrologic and basin characteristics. Results of the study emphasize that the characteristics of floods from small and large watersheds are so significantly different that the two problems cannot be combined into one solution. The studies show that the most important hydrologic characteristics in large watersheds were: drainage area size and main channel slope. For small watersheds the most important hydrologic characteristics were: drainage area size, rainfall intensity and soil index. For watershed effect by reservoir storage it was found that: (1) small drainage areas are relatively more affected by storage than large drainage areas; (2) storage of less than 25 acre feet per square mile will not have significant effect on the mean annual flood (for drainage area above 70 square miles).  相似文献   
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