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61.
Summary This paper describes some of today's important information handling products and attempts to predict tomorrows devices in the light of convergence and greater flexibility offered through the use of microchip technology.The main contention of this paper is that Information Technology and its impact on privacy depends, as ever, on the way in which Information Systems are used. It is argued that the privacy issue is more to do with moral and physiological attitudes within society than the technicalities of implementation.As a conclusion, the paper asks that we should define standards and exercise vigilance in the maintenance of those standards. In addition, it recognises that attitudes to privacy will almost certainly change with time and that this should be regarded as a healthy and natural occurrence.Roger Reynolds has worked in the computer industry for 18 years and has experience in both hardware design and systems development. He has been employed in ICL for the last 5 years and has been deeply involved with the development of communications and Information Technology within this company.Previously he worked on a project designed to integrate various activities in the health service. This involved the development of computer based systems connected together by telecommunications.This article represents a personal view by Mr Reynolds and it is hoped that it will stimulate further thought and understanding in the development of future technologies.  相似文献   
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63.
Conservation planning tends to focus on protecting species’ ranges or landscape connectivity but seldom both—particularly in the case of diverse taxonomic assemblages and multiple planning goals. Therefore, information on potential trade-offs between maintaining landscape connectivity and achieving other conservation objectives is lacking. We developed an optimization approach to prioritize the maximal protection of species’ ranges, ecosystem types, and forest carbon stocks, while also including habitat connectivity for range-shifting species and dispersal corridors to link protected area. We applied our approach to Sabah, Malaysia, where the state government mandated an increase in protected-area coverage of approximately 305,000 ha but did not specify where new protected areas should be. Compared with a conservation planning approach that did not incorporate the 2 connectivity features, our approach increased the protection of dispersal corridors and elevational connectivity by 13% and 21%, respectively. Coverage of vertebrate and plant species’ ranges and forest types were the same whether connectivity was included or excluded. Our approach protected 2% less forest carbon and 3% less butterfly range than when connectivity features were not included. Hence, the inclusion of connectivity into conservation planning can generate large increases in the protection of landscape connectivity with minimal loss of representation of other conservation targets.  相似文献   
64.
The concentrations of manganese (Mn) in the Upper River Severn (the Plynlimon catchments) are examined in relation to rainfall, cloud water, throughfall, stemflow and stream water concentrations where there is over 20 years of monitoring data available. Manganese concentrations are particularly low in rainfall and cloud water, with maximum concentrations occurring under low volumes of catch due to atmospheric "washout" of contaminants and dry deposition. There is strong Mn enrichment in throughfall and stemflow and this is probably linked to cycling through the vegetation. Manganese in the streams and groundwaters are primarily supplied from within-catchment sources. The highest concentrations occur within the tree canopy probably due to element cycling and in groundwaters due to mobilisation from the rock. Manganese concentrations in streams are at their lowest during spring and summer following long dry spells, with rapid increases following subsequent rain. There is no clear long-term trend in Mn concentration in the streams although there are increases in Mn concentrations for years when there is extensive felling of spruce plantation forest and in 1995 following a more extensive dry period. New high resolution monitoring picks up the effects of the rising limb of the hydrograph when concentrations rapidly increase, diurnal patterns during summer low-flow periods and contrasting dynamics between moorland and forested catchments.  相似文献   
65.
The goal of this study was to determine if a cytopathogenic effects (CPE) cell culture assay and an integrated cell culture PCR (ICC-PCR) assay would yield similar or different results when used to assess virus survival in water. Poliovirus type 1 was added to dechlorinated tapwater and stored at room temperature (22.5–24°C) for a total of 50 days. Samples were assayed at defined time intervals by the most probable number (MPN) method on Buffalo green monkey kidney cells (BGM) by CPE and additionally by ICC-PCR. Monolayers that were CPE negative on first passage were passed onto fresh monolayers of cells for a second and third time if still negative. By CPE assay, second passage was observed to yield a greater titer (2,300 vs. 24,000 MPN/ml) and third passage also resulted in an increased titer. ICC-PCR proved to be a more rapid and sensitive method than conventional cell culture for determining virus inactivation rates in water. Poliovirus survived in tapwater for up to 32 days, as assessed by both third passage ICC-PCR and CPE. There was no statistical difference in the inactivation rates between the two methods. To determine the total number of infectious viruses, these findings indicate the need for performing three cell culture passages or, alternatively, ICC-PCR on first passage.  相似文献   
66.
A field-based system used to quantify the response of acid grassland to reduced atmospheric nitrogen and sulphur deposition, and to investigate the effects of elevated soil temperature on acid grassland development is described. The system is based on 12 retractable roofs, covering undisturbed experimental plots of acid grassland and three controls. Nine roofs are used to exclude natural precipitation and three roofs used to retain emitted IR radiation at night. An irrigation system has been developed to simulate natural precipitation, allowing for the application of specific treatment regimes of ambient, reduced nitrogen and reduced nitrogen/sulphur deposition beneath the nine rain exclusion plots. Plant, soil parameters, leachate chemistry and gaseous fluxes are being monitored and initial results on soil water chemistry are described. Warming appeared to enhance nitrate concentrations in soil water but this was not sustained beyond the first year of treatment. In contrast, the deposition reduction treatments decreased soil water nitrate concentrations within a few weeks of reducing deposition. This was not observed for other solutes such as sulphate or ammonium suggesting a more direct link between deposition of nitrate and leaching losses.  相似文献   
67.
The Simple Mass Balance (SMB) equationis commonly used throughout Europe for thecalculation of acidity critical loads for forestsoils. Different criteria can be set in themodel depending on whether the receptor (e.g. treeroots) is more sensitive to the toxic effects ofaluminium or to unfavourable pH conditions. Thispaper examines the effects on critical loadscalculations of using different criteria andcritical limits, and demonstrates the importanceof selecting the most appropriate and justifiablecriteria for the chosen receptor, since they caneffect the critical loads values obtained. Abrief review of the range of different criteriaand limits used throughout Europe is included. In addition, the gibbsite equilibrium constant,used in the SMB equation to represent therelationship between dissolved aluminium andhydrogen ions in soil solution, is discussed. This relationship is not generally described inthe literature as a criterion in the equation,but this work highlights the effects differentgibbsite values have on critical loadcalculations and the importance of applying themost appropriate value for the soil in therooting zone of the receptor.  相似文献   
68.
以来自2 个水稻杂交组合的后代遗传群体为材料,研究了蜡质基因( Wx) 微卫星标记(CT)n 多态性与稻米表观直链淀粉质量分数( w(AA)) 之间的相关性. 第1 个群体是浙农8010 与嘉育293 的杂交F6 代育种品系,双亲均为籼稻,w(AA) 分别为8 .7% 和25.6 % ,Wx 基因型为分别为(CT)18(CT)18 和(CT)11(CT)11 .另一群体为CM101 与IGRA409 杂交F5 家系,亲本CM101 为一个粳型糯稻,Wx 基因型为(CT)18(CT)18 ;IGRA409 为籼稻,w(AA) = 27.5% ,Wx 基因型为(CT)11(CT)11 .结果发现,在2 个杂交组合的后代群体中,高w(AA) 材料Wx 基因型均为(CT)11(CT)11 ,低w(AA) 及糯稻的均为(CT)18(CT)18 ,中等w(AA) 材料的则为(CT)18(CT)11 的杂合体.统计分析表明,Wx 基因型与w(AA)之间存在显著的相关性,在浙农8010×嘉育293 和CM101 ×IGRA409 两个群体中相关系数分别达0 .9509 和0.9704.  相似文献   
69.
Despite the widespread application of photochemical air quality models (AQMs) in U.S. state implementation planning (SIP) for attainment of the ambient ozone standard, documentation for the reliability of projections has remained highly subjective. An "idealized" evaluation framework is proposed that provides a means for assessing reliability. Applied to 18 cases of regulatory modeling in the early 1990s in North America, a comparative review of these applications is reported. The intercomparisons suggest that more than two thirds of these AQM applications suffered from having inadequate air quality and meteorological databases. Emissions representations often were unreliable; uncertainties were too high. More than two thirds of the performance evaluation efforts were judged to be substandard compared with idealized goals. Meteorological conditions chosen according regulatory guidelines were limited to one or two cases and tended to be similar, thus limiting the extent to which public policy makers could be confident that the emission controls adopted would yield attainment for a broad range of adverse atmospheric conditions. More than half of the studies reviewed did not give sufficient attention to addressing the potential for compensating errors. Corroborative analyses were conducted in only one of the 18 studies reviewed. Insufficient attention was given to the estimation of model and/or input database errors, uncertainties, or variability in all of the cases examined. However, recent SIP and policy-related regional modeling provides evidence of substantial improvements in the underlying science and available modeling systems used for regulatory decision making. Nevertheless, the availability of suitable databases to support increasingly sophisticated modeling continues to be a concern for many locations. Thus, AQM results may still be subject to significant uncertainties. The evaluative process used here provides a framework for modelers and public policy makers to assess the adequacy of contemporary and future modeling work.  相似文献   
70.
Much uncertainty still exists regarding the relative importance of organic acids in relation to acid deposition in controlling the acidity of soil and surface waters. This paper contributes to this debate by presenting analysis of seasonal variations in atmospheric deposition, soil solution and stream water chemistry for two UK headwater catchments with contrasting soils. Acid neutralising capacity (ANC), dissolved organic carbon (DOC) concentrations and the Na:Cl ratio of soil and stream waters displayed strong seasonal patterns with little seasonal variation observed in soil water pH. These patterns, plus the strong relationships between ANC, Cl and DOC, suggest that cation exchange and seasonal changes in the production of DOC and seasalt deposition are driving a shift in the proportion of acidity attributable to strong acid anions, from atmospheric deposition, during winter to predominantly organic acids in summer.  相似文献   
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