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81.
Grondin Y Matthews K McEntee M Rainford L Casey M Tonra M Al-Qattan E McCrudden T Foley M Brennan PC 《Radiation protection dosimetry》2004,108(2):123-132
This work, using an adult anthropomorphic phantom, aimed to establish an optimised technique for ladies of child-bearing age undergoing antero-posterior (AP) pelvis and AP and lateral lumbar spine examinations. Phase one of the work involved introducing the following dose-reducing measures individually: increased kVp, increased focus-film distances, a carbon fibre cassette, a faster film/screen combination. The second phase established an optimised technique based on a combination of the parameters listed above. Radiation dose was measured using thermoluminescent dosimeters and image quality was evaluated using anatomical criteria. All dose-reducing methods were compared with a standard technique, currently being used in a Dublin hospital. The results demonstrated that the optimised procedure reduced effective dose by 77, 62 and 66% for AP pelvis and AP and lateral lumbar spine respectively (p < 0.05) compared with the standard technique, with no significant changes in image quality. Dose-reducing measures used in combination offer substantial potential for optimisation of radiological procedures. 相似文献
82.
This article reviews the early days of an Australian public broadcaster's open studio Web project. It raises important issues for software developers and Web media makers about the need for software and collaborative structures that can facilitate community building in an open and responsive way. This project could be of interest to software developers working in Drupal. 相似文献
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Technology-aided participative methods in environmental assessment: An international perspective 总被引:1,自引:0,他引:1
Ainhoa Gonzlez Alan Gilmer Ronan Foley John Sweeney John Fry 《Computers, Environment and Urban Systems》2008,32(4):303
Provisions for citizen involvement in the assessment of potential environmental effects of certain plans, programmes and projects are present in current legislation. An international survey revealed that public participation is common practice in European and some other countries worldwide. However, a number of issues are observed to affect public involvement in EIA/SEA processes and expert opinion differs when evaluating the effectiveness of existing participative methods.Results suggest that technology-aided methods can improve traditional participation processes. In particular, GIS has the potential to increase community knowledge and enhance involvement by communicating information more effectively. Variable accessibility to technology and data quality remain issues. Combining technology with more conventional ways of gathering, evaluating and presenting data are seen as offering a solution to the need to promote the integration of public perceptions in environmental assessment procedures. Recommendations to improve current public participation methods and measures for making GIS available to the general public are provided. 相似文献
85.
Ras proteins are membrane-associated guanine nucleotide-binding proteins that serve as molecular switches for signal transduction pathways in a diverse array of organisms. Various cellular factors are known to interact with Ras proteins. In order to find the novel cellular factors that are associated with Ras function, we have constructed synthetic lethal mutants of the ras1+ gene in Schizosaccharomyces pombe and used them to identify the genes that are functionally dependent on the Ras1. We first constructed S. pombe strains in which chromosomal ras1+ gene is placed under the nmt1 promoter that is regulated by thiamine. This strain shows ras1+ phenotype in the absence of thiamine, whereas it shows ras1- phenotype in the presence of thiamine. Second, we mutated the constructed strains with ultraviolet light (UV) and selected two synthetic lethal mutants that could not grow when Ras1 function was repressed (ras1-). One of the mutants, KSC3, showed a swollen cell shape, aberrant deposition of septum materials, and aberrant nuclei. The other mutant, KSC4, showed sensitivity to hyper-osmolarity when Ras1 function is absent. These mutants, however, grow normally when Ras1 is expressed (ras1+). These two novel synthetic lethal mutants of ras1 provide the means to isolate the corresponding genes that function in association with Ras1 in S. pombe. Screening of a genomic library of S. pombe complementing the mutant phenotype allowed us to identify several novel genes associated with Ras1 of S. pombe. 相似文献
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In this study the desizing, scouring, bleaching and slack mercerising of cotton fabric by a one–step process at different sodium hydroxide concentrations, impregnation temperatures and curing times were examined. The results indicate that when the fabrics are mercerised at lower temperature, the strength retention and colour strength are enhanced. When the sodium hydroxide concentration is increased, these properties also increase. When cotton fabrics are mercerised for 3 min at 40C and cured for 30 s at 120C, their physical properties are similar to those obtained using a conventional two–step approach. 相似文献
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根据濮城西区沙二上2+3油藏层内矛盾突出的地质特点,提出并实施了远井调剖-近井封口的区块深部调剖试验,并将PI决策技术作为深部调剖选井、选剂、定量以及效果评价的理论基础,现场试验结果表明油藏的均质性明显增强,为厚层非均质油藏进入高含水开发提供了有益的借鉴。 相似文献
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