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Abstract There are still many institutions of higher education in the UK, both universities and polytechnics, that have not taken on board the application of information technology to foreign language learning. Apart from considerations of cost, there is also the problem of time—deciding how best to use the limited time at one's disposal for exploring computer applications to foreign language learning. Both problems may be compounded by the mistaken belief that effective use of this 'new' technology necessarily involves learning one or more programming languages. This paper endeavours to show that recent advances in both software and hardware have produced computing tools of particular interest to translation and the translator, and that, since translation is a reality for large numbers of undergraduates in the UK, such tools represent an obvious starting point for the introduction of IT into the undergraduate curriculum.  相似文献   
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We evaluated the influence of sediment characteristics, acid-volatile sulfide (AVS) and organic matter (OM), on the toxicity of chromium (Cr) in freshwater sediments. We conducted chronic (28-42-d) toxicitytests with the amphipod Hyalella azteca exposed to Cr(VI) and Cr(III) in water and in spiked sediments. Waterborne Cr(VI) caused reduced survival of amphipods with a median lethal concentration (LC50) of 40 microg/L. Cr(VI) spiked into test sediments with differing levels of AVS resulted in graded decreases in AVS and sediment OM. Only Cr(VI)-spiked sediments with low AVS concentrations (< 1micromol/g) caused significant amphipod mortality. Waterborne Cr(III) concentrations near solubility limits caused decreased survival of amphipods at pH 7 and pH 8 but not at pH 6. Sediments spiked with high levels of Cr(III) did not affect amphipod survival but had minor effects on growth and inconsistent effects on reproduction. Pore waters of some Cr(III)-spiked sediments contained measurable concentrations of Cr(VI), but observed toxic effects did not correspond closely to Cr concentrations in sediment or pore waters. Our results indicate that risks of Cr toxicity are low in freshwater sediments containing substantial concentrations of AVS.  相似文献   
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A method of reporting results from digital simulations is presented and illustrated. The method is particularly useful when alternative approaches to the solution of a problem are to be compared. The method focuses on the reporting of standard errors, a result of paramount importance, and all too often overlooked.  相似文献   
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Inspection error has clearly been shown to have adverse effects upon the results desired from a quality assurance sampling plan. These effects upon performance measures have been well documented from a statistical point of view. However, little work has been presented to convice the QC manager of the unfavorable cost consequences resulting from inspection error. This paper develops a very general, yet easily used, mathematical cost model. The basic format of the well-known Guthrie-Johns model is used. However, it is modified as required to assess the effects of attributes sampling errors of the first and second kind. The economic results, under different, yet realistic conditions, will no doubt be of interest to QC practitioners who face similar problems daily. Sampling inspection plans are optimized to minimize economic losses due to inspection error. Unfortunately, any error at all results in some economic loss which cannot be compensated for by sampling plan design; however, improvements over plans which neglect the presence of inspection error are possible. Implications for human performance betterment programs are apparent, as are trade-offs between sampling plan modification and inspection and training improvement economics.  相似文献   
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Recent research on industrial quality control systems has emphasized economic modeling in contrast with earlier works based primarily on statistical considerations. Often treated as separate systems, process control and acceptance sampling have received considerable attention from the cost based approach. This article brings together these two related quality control functions through the development of an economic model for the situation in which lot by lot sampling has the dual purpose of controlling the lot mean and determining lot disposition  相似文献   
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The blocking effect of apomorphine on the rise in striatal dopamine (DA) content, induced by 1-hydroxy-3-amino-pyrrolidone-2 (HA-966) was taken as a measure for the intrastriatal feedback inhibition of DA synthesis. The effects of cholinergic drugs on this feedback system were assessed in order to verify the hypothesis that this mechanism is mediated via an intrastriatal cholinergic link. We presumed that DA receptors were located on a cholinergic neuron, while the cholinergic terminals in turn made direct or indirect axon-axonal contact with the dopaminergic nigro-striatal pathway (N.S.P.). Although cholinergic agents could modify the effect of HA-966 on striatal DA content, it proved to be impossible to counteract the blocking effect of apomorphine with cholinergic drugs as was to be expected. Therefore we concluded that the effect of apomorphine was not brought about in the way which had been postulated.  相似文献   
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A nationally consistent approach was used to assess the occurrence and potential sources of pyrethroid insecticides in stream bed sediments from seven metropolitan areas across the United States. One or more pyrethroids were detected in almost half of the samples, with bifenthrin detected the most frequently (41%) and in each metropolitan area. Cyhalothrin, cypermethrin, permethrin, and resmethrin were detected much less frequently. Pyrethroid concentrations and Hyalella azteca mortality in 28-d tests were lower than in most urban stream studies. Log-transformed total pyrethroid toxic units (TUs) were significantly correlated with survival and bifenthrin was likely responsible for the majority of the observed toxicity. Sampling sites spanned a wide range of urbanization and log-transformed total pyrethroid concentrations were significantly correlated with urban land use. Dallas/Fort Worth had the highest pyrethroid detection frequency (89%), the greatest number of pyrethroids (4), and some of the highest concentrations. Salt Lake City had a similar percentage of detections but only bifenthrin was detected and at lower concentrations. The variation in pyrethroid concentrations among metropolitan areas suggests regional differences in pyrethroid use and transport processes. This study shows that pyrethroids commonly occur in urban stream sediments and may be contributing to sediment toxicity across the country.  相似文献   
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