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991.
Food irradiation in the UK and the European Directive 总被引:2,自引:0,他引:2
Food irradiation in the UK has been authorised since the early 1990s. In principle it is possible to irradiate a wide range of foods for a variety of purposes. In practice food irradiation is virtually non-existent. The structure of food retailing in the UK, a continual stream of food safety scares and a developing public ‘crisis of confidence’ in the food producer/supply chain have combined to make the future for food irradiation look bleak. The new European Directive on Food Irradiation is unlikely to alter this outlook. 相似文献
992.
G. T. Sanders 《Accreditation and quality assurance》2000,5(12):482-484
The European Register for Clinical Chemists is founded and guarded by the European Communities Confederation of Clinical
Chemistry (EC4). This register fits the current mind set of harmonization and globalization of occupations within the European
Community. But in addition it enables and serves the continuing quest for quality assessment and improvement within the field
of laboratory medicine. The content and position of clinical chemists in the European Union is described and the European
Register outlined.
Received: 10 July 2000 / Accepted: 20 July 2000 相似文献
993.
Hall Peter Härdle Wolfgang Kleinow Torsten Schmidt Peter 《Statistical Inference for Stochastic Processes》2000,3(3):263-276
A major application of rescaled adjusted range analysis (R–S analysis) is to the study of price fluctuations in financial
markets. There, the value of the Hurst constant, H, in a time series may be interpreted as an indicator of the irregularity of the price of a commodity, currency or similar
quantity. Interval estimation and hypothesis testing for H are central to comparative quantitative analysis. In this paper we propose a new bootstrap, or Monte Carlo, approach to such
problems. Traditional bootstrap methods in this context are based on fitting a process chosen from a wide but relatively conventional
range of discrete time series models, including autoregressions, moving averages, autoregressive moving averages and many
more. By way of contrast we suggest simulation using a single type of continuous-time process, with its fractal dimension.
We provide theoretical justification for this method, and explore its numerical properties and statistical performance by
application to real data on commodity prices and exchange rates.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
994.
995.
具指数赋权指标的证券投资多目标线性规划模型 总被引:2,自引:0,他引:2
本文提出证券投资决策的指数赋权指标体系.在该指标体系中,建立风险证券组合投资决策和存在无风险证券或无风险贷款时证券组合投资决策的多目标线性规划模型.研究了有效风险证券组合集和有效证券组合集的结构和相互关系,市场证券组合以及证券均衡市场价格和投资风险分析. 相似文献
996.
《Arabian Journal of Chemistry》2023,16(3):104521
The continuous development of resistance to antibiotic drugs by microorganisms causes high mortality and morbidity. Pathogens with distinct features and biochemical abilities make them destructive to human health. Therefore, early identification of the pathogen is of substantial importance for quick ailments and healthcare outcomes. Several phenotype methods are used for the identification and resistance determination but most of the conventional procedures are time-consuming, costly, and give qualitative results. Recently, great focus has been made on the utilization of advanced techniques for microbial identification. This review is focused on the research studies performed in the last five years for the identification of microorganisms particularly, bacteria using advanced spectroscopic techniques including mass spectrometry (MS), infrared (IR) spectroscopy, Raman spectroscopy (RS), and nuclear magnetic resonance (NMR) spectroscopy. Among all the techniques, MS techniques, particularly MALDI-TOF/MS have been widely utilized for microbial identification. A total of 44 bacteria i.e., 6 Staphylococcus spp., 3 Enterococcus spp., 6 Bacillus spp., 4 Streptococcus spp., 6 Salmonella spp., and one from each genus including Escherichia, Acinetobacter, Pseudomonas, Proteus, Clostridioides, Candida, Brucella, Burkholderia, Francisella, Yersinia, Moraxella, Vibrio, Shigella, Serratia, Citrobacter, and Haemophilus (spp.) were discussed in the review for their identification using the above-mentioned techniques. Among all the identified microorganisms, 21% of studies have been conducted for the identification of E. coli, 14% for S. aureus followed by 37% for other microorganisms. 相似文献