The pedagogy of atmospheric issues and the UK Atmospheric Research and Information Centre's Education Programme

Mrs Sue Hare is the education and information services coordinator of the UK Atmospheric Research and Information Centre (ARIC). Professor James Longhurst was recently the director of the ARIC and Joe Buchdahl its global climate change information services coordinator. Professor Longhurst is now head of the Department of Environmental Health and Science, University of the West of England, Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY. Kelvin Williams is a geography consultant and is head of geography at Ysgol y Creuddyn, Penrhyn Bay, Llandudno, Gwynedd LL30 3LB. The pedagogy of atmospheric issues is identified in the context of environmental education in this paper. The UK Atmospheric Research and Information Centre (ARIC) has developed an education programme which has responded to the dynamic issues relating to the atmosphere since the establishment of the ARIC in 1984. The main route for the teaching of atmospheric issues is identified as being through the UK's National Curriculum although public awareness of issues has increased through the media and more recently through government publicity campaigns.     

Development of a Standardised Approach to River Habitat Assessment in Australia

Despite the demonstrated utility of the Australian River Assessment Scheme (AUSRIVAS) to provide national-scale information on the biological condition of rivers, there is no commensurate scheme that can provide standardised information on physical habitat. Existing habitat assessment methods are not suitable for implementation on a national scale, so we present a new habitat assessment protocol that incorporates favorable elements of existing methods. Habitat Predictive Modelling forms the basis for the protocol because it can predict the occurrence of local-scale features from large-scale data, uses the reference condition concept, can be modified to incorporate a range of biologically and geomorphologically relevant variables, and employs a rapid survey approach. However, the protocol has been augmented with geomorphological variables and incorporates principles of hierarchy and geomorphological river zonation. There are four sequential components to the implementation of the protocol: reference site selection, data collection, predictive model construction and assessment of test sites using the predictive models. Once implemented, the habitat assessment protocol will provide a standardised tool for the assessment of river habitat condition at a variety of governance levels.     

Examination of the influence of dissolved halite (NaCl) on the leaching of lead (Pb) from cement-based solidified wastes

The leaching of lead from cement-based solidified waste forms mixed at different water/cement ratios was studied by conducting equilibrium and semi-dynamic leaching tests using deionized water and sodium chloride solutions. The results suggest that leaching of the primary constituents of the cement (calcium, silicon and sulfate) is controlled by solubility equilibria, with increased leaching into chloride solutions due to ionic strength effects. The original porosity of the waste forms increased with water/cement ratio and chloride solutions further increased it as a result of decalcification. Lead leaching was generally low, and appears to be a transport-controlled process, such that leaching correlates positively with porosity.     

Self-leadership and performance outcomes: the mediating influence of self-efficacy

A key foundation of empowering organizations is employee self-leadership. This study examines the effects of self-leadership skills and self-efficacy perceptions on performance. Structural equations modeling determined whether the influence of self-leadership on performance is mediated by self-efficacy perceptions. Results for the sample of 151 respondents indicated self-leadership strategies had a significant effect on self-efficacy evaluations, and self-efficacy directly affected performance. Further, self-efficacy perceptions were found to fully mediate the self-leadership/performance relationship. Theoretical and practical implications are discussed. © 1998 John Wiley & Sons, Ltd.     

The implementation of a human factors engineering checklist for human–system interfaces upgrade in nuclear power plants

The primary purpose of this paper is to provide a human factors engineering (HFE) checklist for human–system interfaces (HSIs) upgrades in nuclear power plants (NPPs). The HFE checklist is used to review the HSIs design submittals prepared by licensees or applicants for a license or design certification of a HSI upgrade. NUREG-series regulation documents are used to develop the main frame of the initial HFE checklist. The contents of the HFE checklist are constructed by the theories and principles governing human factors. Then, verification and validation (V&V) of the HFE checklist is accomplished by validity and reliability evaluation. The results show that the HFE checklist has sufficient validity and reliability for the review of HSI upgrades in NPPs.     

Ethylene Dosages in Denver and Marketability of Cut-Flower Carnations

Ethylene dosages required to reduce keeping life of the cut-flower, Dianthus caryophyllus L. cv “White Sim,” were compared with dosages estimated from air samples obtained in selected locations of the Denver Metropolitan region. Ethylene concentrations sufficiently high and prolonged to reduce significantly flower longevity prior to final sale are seldom attained. If flowers are harvested in an immature stage and immediately refrigerated, there should not be any economic loss. But, damage is likely after the flower is purchased and displayed at room temperature. Regardless of quality maintained in the marketing processes by the greenhouse industry, severe consumer dissatisfaction may result when ethylene sensitive plant material is purchased. The results emphasize means of avoiding pollution damage from ethylene.     

Carbon bed mercury emissions control for mixed waste treatment

Mercury has various uses in nuclear fuel reprocessing and other nuclear processes, and so it is often present in radioactive and mixed (radioactive and hazardous) wastes. Compliance with air emission regulations such as the Hazardous Waste Combustor (HWC) Maximum Achievable Control Technology (MACT) standards can require off-gas mercury removal efficiencies up to 99.999% for thermally treating some mixed waste streams. Test programs have demonstrated this level of off-gas mercury control using fixed beds of granular sulfur-impregnated activated carbon. Other results of these tests include (1) the depth of the mercury control mass transfer zone was less than 15-30 cm for the operating conditions of these tests; (2) MERSORB carbon can sorb mercury up to 19 wt % of the carbon mass; and (3) the spent carbon retained almost all (98.3-99.99%) of the mercury during Toxicity Characteristic Leachability Procedure (TCLP) tests, but when even a small fraction of the total mercury dissolves, the spent carbon can fail the TCLP test when the spent carbon contains high mercury concentrations.     

Recreation demand analysis under truncation, overdispersion, and endogenous stratification: an application to Gros Morne National Park

Using on-site survey data from Gros Morne National Park in Newfoundland, this paper estimates and compares several truncated count data models of recreation demand. The selected model accounts not only for the truncated and overdispersed nature of the data but also for endogenous stratification due to the oversampling of avid users. Moreover, the model that allows for a flexible specification of the overdispersion parameter dominates on the basis of goodness of fit. The results are used to estimate the users' value of access to the park.