Continuous pollution monitoring using Photobacterium phosphoreum

Photobacterium phosphoreum is a marine bacterium which is used extensively as a bioluminescent indicator of pollutants, where the presence of toxicants diminishes light output. To evaluate the utility of cell immobilisation in continuous toxicity testing, the sensitivity of P. phosphoreum to five gelling agents was evaluated relative to the retention of bioluminescence in 3% NaCl-glycerol suspensions. Following storage at 4°C, the control cultures retained light output for up to 2 weeks before significant decline; alginate-glycerol suspensions were stable for up to 4 weeks and bioluminescence was detectable for up to 6 weeks. Cells stored in agar were no more stable than the control, whereas cells gelled in agarose and low-melting point agarose showed a significant decline in bioluminescence within 2 weeks of storage. Bioluminescence was totally retained in alginate-glycerol suspensions stored at −80°C for up to 12 weeks. P. phosphoreum was successfully immobilised in strontium alginate and showed a dose-related response to four of the five heavy metal ions, SDS and pentachlorophenol tested when responses were followed over a time-course. A flow-through system for Sr-alginate immobilised cells was developed and conditions for operation were optimised. When cells were exposed to a pulse of 4-nitrophenol or salicylate then the nutrient feed continued, bioluminescence declined in response (pulse of 4–6 min) to these pollutants then recovered to a new stable rate of decline which was faster than the pre-exposure rate. These results demonstrate the potential of using immobilised P. phosphoreum in a continuous flow-through system for real-time environmental monitoring of water quality.     

Translocations and the Preservation of Allelic Diversity

Translocation is a tool commonly used for the conservation of threatened and endangered fish species. Despite extensive use, the biological implications of translocation remain poorly understood. Of particular interest is the effect of translocation on genetic variability. Maintenance of genetic variability in these "refuge" populations is assumed to be important for both short- and long-term success. We examined allozyme variability at 16 loci for western mosquitofish ( Gambusia affinis ) populations with known histories of introduction. Refuge populations had significantly lower levels of heterozygosity. Refuge populations also had considerably lower levels of allelic diversity than parental populations. All losses were of relatively rare alleles (frequency less than 0.1 in parental population). These losses were probably due to an undocumented bottleneck early in the introduction history. These results were surprising because the initial transplant involved 900 fish and because mosquitofish have numerous reproductive traits that should minimize the effects of bottlenecks on genetic diversity. A literature review revealed that genetic variability is often reduced in refuge populations and that such reductions typically involve the loss of alleles. We suggest that translocated populations be examined periodically for losses of genetic variability.     

SOCIAL FEASIBILITY AS AN ALTERNATIVE APPROACH TO WATER RESOURCE PLANNING1

ABSTRACT: Research suggests that conflict over public participation in water resource planning is due, in part, to confusion over the nature of the policies involved. This article examines the roadblocks to citizen involvement in water resource planning in terms of two policy models: (1) the Social Feasibility Model and (2) the Political Feasibility Model. Each model posits a different role for public participation. Although the Political Feasibility Model has been widely accepted in water resource planning, changes in the nature of the policies involved in water resource management have weakened its appropriateness. Currently, social and redistributive policies involving value conflicts often dominate water planning and these policies are best chosen through the Social Feasibility Model. The article discusses the nature of the social feasibility model, the new types of policy decisions facing water resource managers, and how the social feasibility model can help overcome the roadblocks to increased public participation in water resource policy making.     

The effect of externally set goals on reaching integrative agreements in competitive markets

The study of the negotiation process has enjoyed a recent resurgence of scholarly interest. Of particular concern is the ability of negotiators to achieve solutions which result in integrative outcomes. The purpose of this study is to identify the effects of different levels of aspiration/goals on negotiator success and their ability to reach integrative solutions in a competitive market. One hundred fifty-eight subjects who were assigned one of four levels of goal difficulty-no goal, compromise goal, challenging goal, and difficult goal-participated in a competitive, multi-person, multi-transaction market simulation. The study found (1) challenging and difficult goals significantly enhanced participants' performance; (2) the more difficult the goal, the fewer transactions were completed; and (3) while there were no differences in total profitability among the challenging goal, compromise goal, and no goal, the difficult goal condition had a significant and negative effect on the ability of participants to achieve profitable outcomes within the market. A discussion of these findings and directions for future research are presented.     

An evaluation of Manutention training in preventing back strain and resultant injuries in nurses

As the number of manual handling injuries in carers and nurses continues to be very high, the problem of how to prevent injury has not been solved. Despite the obvious need for optimum working environments, the literature does not really support that an ergonomics or systems approach solves the injury problem. Similarly, the evidence for training as a preventive strategy is equivocal, although clearly people handling requires trained handlers for both their own and the patient's safety. This research aimed to evaluate the outcomes of training in a method of manual handling of people, Dotte's Manutention method, which claims to decrease back strain and effort in carers. The study evaluated handling techniques and injury outcomes of a group of nurses in a nursing home trained in this method, using two other homes as comparisons. The study hypothesized that training in the Manutention method would decrease back strain and resultant back injuries in nurses working in geriatric care. The results showed a clear pattern of declining incidence of nurses' back pain for the nurses trained in Manutention and increasing incidence in the other two homes. These findings approached significance with a probability of < 0.1. Of those respondents who indicated a decrease in pain during the twelve month research period, all attributed it to their training. Ninety four percent of respondents who received training agreed it made their manual handling job easier. The observation method used was not sensitive enough to evaluate the multiple movements involved in a patient transfer. A supplementary controlled study was performed using videotaping and the Ovako Working Assessment System (OWAS). Manutention lifts were rated significantly better than non-Manutention on the critical variable of working posture (p < 0.01) and observed effort (p < 0.05). Accident statistics on patient handling did not show decreased injury rates at twelve months. The difficulties of controlling variables in the workplace and of the measurement of complex handling tasks were limitations of this study.     

Investigation of the concentration and isotopic composition of inputs and outputs of Pb in waters at an upland catchment in NE Scotland

As a consequence of the accumulation of anthropogenic Pb in upland catchments, there has been much recent concern about the potential mobilisation and transport of Pb from the soils to receiving waters and also the possible harmful effects that this might have on aquatic biota. This paper presents the findings of a two-year study of Pb behaviour in an organic-rich upland catchment at Glensaugh in NE Scotland. Pb inputs to the catchment were characterised by direct measurements of Pb concentration and (206)Pb/(207)Pb ratios in rain water and interception. Pb outputs from the catchment were calculated from measurements on stream water samples taken from the two main streams, the Cairn Burn and Birnie Burn. The relative contribution of Pb from groundwater and throughflow, under different flow conditions (base flow and high flow), to stream waters was investigated via analysis of springs sourced from groundwater and of waters flowing through the various soil horizons (S (surface), A, B, C, and D), respectively. The outcome of intensive sampling and analysis over the two-year time period was that, even with marked reduction in Pb inputs over the past two decades, the catchment was still acting as a net sink for the current atmospheric deposition. Although the Pb isotopic signature for stream water is very similar to that for the contemporaneous rain water ((206)Pb/(207)Pb approximately 1.15-1.16), only a small portion of the rain water is transferred directly to stream water. Instead, the Pb input is transferred to the stream waters mainly via groundwater and it was also confirmed that the latter had a similar Pb isotopic signature. From the Pb isotopic measurements on throughflow waters, however, Pb being removed via the streams contained some previously deposited Pb, i.e. mobilisation of a small portion of soil-derived anthropogenic Pb was occurring. These findings are important not only with respect to the source/sink status of the catchment but also for calculation of the extent of retention of the current atmospheric Pb inputs, which must take account of the release of previously deposited Pb from the catchment soils, a process occurring mainly under high flow conditions.     

Variable resource defense by the Tana River crested mangabey

Summary Behavioral observations over 16 months of two groups of Tana River crested mangabeys (Cercocebus galeritus galeritus) in East Africa provide evidence, contrary to previous reports, for site-specific aggression and territorial exclusion. In addition, movements and vocal responses to neighboring group's long-call vocalizations vary temporally, reflecting seasonal variation in food availability and distribution. Patterns of response to neighboring groups are consistent with the hypothesis that resources should be defended only when it is economic to do so. When fruit resources are rare intergroup interactions are infrequent and groups use separate areas. As fruit availability increases, the distribution of diet species influences the type of interaction; peaceful intergroup interactions generally occur when mangabeys eat uniformly distributed species and aggressive interactions occur when mangabeys eat species with patchy distributions. Differences between male vocal responses and group spatial responses may reflect conflicting objectives of territorial defense by males and females.     

Using markets for land preservation: Results of a TDR program

This paper reviews different approaches to using transferable development rights (TDRs) as a way to preserve rural lands in the face of development pressure. One TDR program is examined in detail, that of Calvert County, Maryland, which has had an active TDR market since the mid-1980s. This program uses TDRs as a key policy tool for achieving a total amount of preserved acreage in the county, and for providing incentives for preservation in some areas and development in others. The paper examines both the early difficulties in developing participation in the program, and the events that lead eventually to an active TDR market. It assesses the workings of the market including factors that influence the demand and supply of TDRs, the movement of prices over time, and the location of preserved areas and of additional developed areas. The study found that the program is achieving many of the county's land preservation goals because of the high level of activity in the TDR market. However, most of the additional density is being channeled into rural areas with underlying low-density zoning.