The usability of digestate in organic farming

As organic farming prohibits the use of synthetic fertilisers, animal slurries and manures must be used. Digestate offers an alternative to these and this study reports on three experiments conducted to determine its usability in terms of: (1) the effect on earthworm populations, (2) its fertilising effects on Italian Ryegrass and wild Creeping Thistle, and (3) the suppression effects digestate has on weed emergence. The results for digestate application to field plots were intermediate between slurry and no treatment for earthworm attraction and wild thistle suppression. In glasshouse trials it led to increased ryegrass growth compared with undigested slurry. Analysis showed that the digestate had improved nitrogen availability, leading to increased plant growth, but a reduced organic matter content compared with the slurry, leading to a positive though less beneficial impact on the earthworms. Digestate therefore provides a suitable fertiliser for organic farming. This suitability could be improved by drying or separation to increase the OM content making its properties closer to those of slurry whilst still retaining the higher content of plant available nitrogen.     

Automated image analysis of Euglena gracilis Klebs (Euglenophyta) for measuring sublethal effects of three model contaminants

The short-term impacts of atrazine (herbicide), tributyltin (organometal) and copper on the behaviour of Euglena gracilis Klebs (Euglenophyta) were assessed. First, the ECOTOX automated image analysis system was used, which measured swimming velocity, cell shape, percentage of cells swimming upwards, and randomness of swimming. Next, visual observation by microscopy was used to measure percentage of cell motility and cell shape. Behavioural changes can be used as an indicator of stress in less than 24 h, potentially making them suitable for inclusion in early-warning systems for water quality. Findings indicate that E. gracilis is a very sensitive organism to copper, showing inhibition of motility with visual observation at 0.8 μmol/L within 1 h. The image analysis system was in general less sensitive than visual observation for detecting behavioural changes after incubation in copper. In contrast, after exposure to organic contaminants atrazine and tributyltin, the ECOTOX system detected small changes in the number of cells swimming upwards (antigravitactic behaviour) at higher concentrations.     

Regeneration of barium carbonate from barium sulphide in a pilot-scale bubbling column reactor and utilization for acid mine drainage

Batch regeneration of barium carbonate (BaCO(3)) from barium sulphide (BaS) slurries by passing CO(2) gas into a pilot-scale bubbling column reactor under ambient conditions was used to assess the technical feasibility of BaCO(3) recovery in the Alkali Barium Calcium (ABC) desalination process and its use for sulphate removal from high sulphate Acid Mine Drainage (AMD). The effect of key process parameters, such as BaS slurry concentration and CO(2) flow rate on the carbonation, as well as the extent of sulphate removal from AMD using the recovered BaCO(3) were investigated. It was observed that the carbonation reaction rate for BaCO(3) regeneration in a bubbling column reactor significantly increased with increase in carbon dioxide (CO(2)) flow rate whereas the BaS slurry content within the range 5-10% slurry content did not significantly affect the carbonation rate. The CO(2) flow rate also had an impact on the BaCO(3) morphology. The BaCO(3) recovered from the pilot-scale bubbling column reactor demonstrated effective sulphate removal ability during AMD treatment compared with commercial BaCO(3).     

Exclusive Contracts And Market Power: Evidence From Ocean Shipping

There is a substantial theoretical literature on the potential effects of loyalty contracts, but relatively little empirical work. We employ the event study methodology to examine the competitive effects of exclusionary contracts in the ocean shipping industry, where they were the subject of an extended legal and political struggle. We find that some of the most important events in this conflict caused significant changes in shipping firms' stock returns, indicating exclusive contracts increased their profits. We then examine the effect of these events on net exporting industries' stock returns, and provide evidence that these contracts contributed to carriers' market power.     

PDMA Success Measurement Project: Recommended Measures for Product Development Success and Failure

Success is not just elusive; it is also multifaceted and difficult to measure. A firm can assess the success or failure of a development project in any (or all) of many terms, including customer satisfaction, financial return, and technical advantage. To complicate matters, success may be measured not only at the level of the individual project, but also at the program level. With so many variables to consider and so many stakeholders involved, managers face a difficult challenge just deciding which measures are useful for measuring product development success. Recognizing that no single measure suffices for gauging the success of every product development project, Abbie Griffin and Albert L. Page hypothesize that the most appropriate set of measures for assessing project-level success depends on the project strategy. For example, the objectives (and thus, the success criteria) for a new product that creates an entirely new market will differ from those of a project that extends an existing product line. Similarly, they hypothesize that the appropriate measures of a product development program's overall success depend on the firm's innovation strategy. For example, a firm that values being first to market will measure success in different terms from those used by a firm that focuses on maintaining a secure market niche. To test these hypotheses, product development professionals were presented with six project strategy scenarios and four business strategy scenarios. For each project strategy scenario, participants were asked to select the four most useful measures of project success. For each business strategy scenario, participants were asked to choose the set of four measures that would provide the most useful overall assessment of product development success. The responses strongly support the idea that the most appropriate measures of project-level and program-level success depend on the firm's project strategy and business strategy, respectively. For example, customer satisfaction and customer acceptance were among the most useful customer-based measures of success for several project strategies, but market share was cited as the most useful customer-based measure for projects involving new-to-the-company products or line extensions. At the program level, firms with a business strategy that places little emphasis on innovation need to focus on measuring the efficiency of their product development program, while innovative firms need to assess the program's contribution to company growth.     

Why Do Firms Adopt Profit-Sharing and Employee Ownership Plans?

Profit-sharing and employee ownership in companies have attracted considerable interest, yet there has been little research on factors predicting the adoption and maintenance of these plans. This study uses new data from a survey of 500 US public companies, and panel data on corporate financial variables, to examine factors predicting the presence and adoption of profit- sharing and employee stock ownership plans (ESOPs) in the 1975–91 period. Several findings support productivity-related motivations for such plans (including higher R&D levels among old profit-sharing firms, and recent adoption of job enrichment programmes among new profit-sharing firms), while others support flexibility-related motivations (including higher variance in profits prior to the adoption of profit-sharing plans and ESOPs). Unionized firms were less likely to have either type of plan in 1975, but equally likely to adopt them subsequently (often in concessionary contracts). Comparisons of cross-sectional and panel results illustrate advantages of panel data in disentangling the causes and effects of profit-sharing and ESOPs.