Young fire ant workers feign death and survive aggressive neighbors

Feigning death is a method of self-defense employed among a wide range of prey species when threatened by predator species. This paper reports on death-feigning behavior by the fire ant, Solenopsis invicta, during intraspecific aggression among neighboring fire ant workers. Days-old workers responded to aggression by death feigning, weeks-old workers responded by fleeing and months-old workers responded by fighting back. By feigning death, days-old workers were four times more likely to survive aggression than older workers. From a proximate perspective, retaliation by young workers against aggressive older workers is certain to fail. With their relatively soft exoskeleton, young workers would be prone to injury and death and unable to execute an effective attack of biting or stinging older workers with harder exoskeletons. From an ultimate perspective, death feigning allows young workers to survive and contribute to brood care and colony growth, both of which are essential to queen survival and fitness.     

Modification of evaluation method for auto-assessment and electronic submission by businesses

SUMMARY

This paper describes the evolution of an evaluation method developed initially to assess progress towards sustainable development for various land use activities in Costa Rica. Since that time, the method has been expanded to apply to all types of business activities in any location, and refined so that a numerical score can be provided for each attribute. These scores can then be presented graphically in four categories. The method has since been tested on a variety of businesses and is being refined for electronic submission and display of the results. The benefits of this approach, as well as its shortcomings and some of the problems resolved, are presented.     

Organizational neuroscience: The promise and prospects of an emerging discipline

We review and discuss an Organizational Neuroscience perspective on management science research. Reviewing recent findings in the brain sciences, we provide concrete examples of how an organizational neuroscience perspective can advance organizational behavior research. We conclude that this new paradigm offers powerful insights and tools that complement traditional organizational research. Copyright © 2010 John Wiley & Sons, Ltd.     

Economic aspects of the rehabilitation of the Hiriya landfill

The Hiriya landfill, Israel's largest, operated from 1952 to 1998. The landfill, located in the heart of the Dan Region, developed over the years into a major landscape nuisance and environmental hazard. In 1998, the Israeli government decided to close the landfill, and in 2001 rehabilitation activities began at the site, including site investigations, engineering and scientific evaluations, and end-use planning. The purpose of the present research is to perform a cost-benefit analysis of engineering and architectural-landscape rehabilitation projects considered for the site. An engineering rehabilitation project is required for the reduction of environmental impacts such as greenhouse gas emissions, slope instability and leachate formation. An architectural-landscape rehabilitation project would consider improvements to the site to make it suitable for future end uses such as a public park. The findings reveal that reclamation is worthwhile only in the case of architectural-landscape rehabilitation of the landfill, converting it into a public park. Engineering rehabilitation alone was found to be unjustified, but is essential to enable the development of a public park.     

How to improve reliability in groundwater analysis: over a decade of experience with external quality control in field campaigns on volatile halogenated compounds

The reliability in measurement results obtained during environmental monitoring is crucial for the assessment and further planning of remediation efforts on the respective contaminated sites by the responsible authorities. A case study concerned with groundwater contaminated with perchloroethylene, trichloroethylene and 1,1,2-trichlorotrifluoroethane including their degradation products which involves private contract laboratories and an independent provider of quality assurance (QA) is presented. The experience gained with biannual monitoring campaigns over 14 years indicates that the selection of contractors on basis of accreditation status and successful performance in interlaboratory comparisons are not sufficient. Rather the auditing of the contractors by the QA provider prior to each campaign and the crosschecking of selected monitoring samples by the QA provider led to a lasting improvement of reliability in the contractors' measurement results. A mean deviation of 20% from the reference value determined by the QA provider for the crosschecked samples was reached.     

Perfluorooctane surfactants in waste waters, the major source of river pollution

Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) are persistent and widely distributed in the environment. Recently, the discharge of municipal waste water has been shown to be an important route of such perfluoroalkyl surfactants into the aquatic environment. The aim of this study was to assess the mass flow of PFOA and PFOS from typical waste water treatment plants (WWTPs) into surface waters. Samples were collected at different stages of treatment of four WWTPs in Northern Bavaria, Germany, and from the rivers receiving the treated waste waters (WW). The outflow of PFOA from the WWTPs to the rivers was 20-fold higher than the inflow to the plants; about a tenth was removed with the sludge. For PFOS, the increase from inlet to outlet was about 3-fold; almost half of it was retained in the sludge. Both surfactants were released into river water from the WWTP of a medium-sized city with domestic, industrial and commercial waste waters; in domestic waste waters the surfactants were found at much lower levels.     

PCBs, DDTs and methyl sulphone metabolites in various tissues of harbour porpoises from Swedish waters

Aryl methyl sulphones of polychlorinated biphenyls (PCBs) and 3-p,p'-DDE (MeSO(2)-PCBs and 3-MeSO(2)-p,p'-DDE), PCBs and Sigma DDTs were analysed in five different tissues (blubber, nuchal fat, liver, muscle, brain) of adult male harbour porpoises from the west coast of Sweden. Two different methods for MeSO(2)-PCBs and 3-MeSO(2)-p,p'-DDE determination were used, gas chromatography-mass spectrometry and gas chromatography-atomic emission detection. Highest concentrations of Sigma MeSO(2)-PCBs were found in liver (0.15-0.49 microg/g lipid wt.), which corresponded to 2.0-2.8% of the Sigma PCBs concentrations. Blubber and nuchal fat showed Sigma MeSO(2)-PCB concentrations that were three to five times lower than those in liver. Concentrations of 3-MeSO(2)-p,p'-DDE in liver, muscle and brain corresponded to 0.26-4.6% of the p,p'-DDE concentrations, while in blubber and nuchal fat, 3-MeSO(2)-p,p'-DDE constituted 0.033-0.21% of p,p'-DDE. The different tissues analysed showed similar levels (lipid wt.) of Sigma PCBs and Sigma DDTs, except for brain that had almost 10 times lower levels compared to the other tissues. Using the Sigma PCBs/Sigma MeSO(2)-PCBs ratio to estimate MeSO(2)-PCB formation and secondary metabolism capacity, the harbour porpoise showed a relatively low capacity of MeSO(2)-PCB formation compared to other small toothed whales and seals. Blubber sampled from five different anatomical locations showed that concentrations of contaminants may be unevenly distributed in blubber in certain animals. This should be taken into account when choosing sampling sites on the porpoise.