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Neurotoxic insecticides are widely used for crop protection and behavioural perturbations can be expected in surviving beneficial insects, including parasitoids of pest insects. The present study aims to investigate the relationship between the dose of insecticide parasitoids have been exposed to, and the subsequent ability of these parasitoids to respond to host-related cues. A four-armed olfactometer, a design widely used to observe orientation responses in various insects and parasitoids in particular, was chosen to investigate the dose-response relationship. The species studied was Aphidius ervi, a relatively generalist parasitoid of aphids, and commercialised for biological control and integrated pest management. Active ingredients with similar and different modes of action on the nervous system were compared: a pyrethroid (lambda-cyhalothrin), an organophosphate (chlorpyrifos), a carbamate (pirimicarb) and a carbamyltriazole (triazamate). Adult females were exposed to dry residues on glass for 24 h. LD50 were calculated and predicted a high risk of mortality at the field application rate. The effect of five increasing residual doses of each active ingredient was tested on responses to plant-host odour in the olfactometer, from sublethal doses to LD50, and up to LD70 for some products. It appeared that none of the doses of lambda-cyhalothrin, chlorpyriphos and pirimicarb had any effect on A. ervi responses to the odour from the aphid-infested plant (Myzus persicae on oilseed rape). But for triazamate, a significant dose-behavioural response was quantified and attraction to the odour was no longer significant in females surviving the LD50. The possible explanations for the presence or absence of effect, depending on the insecticide are discussed.  相似文献   
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Geographic information systems (GIS), global positioning systems and remote sensing have been increasingly used in public health settings since the 1990s, but application of these methods in humanitarian emergencies has been less documented. Recent areas of application of GIS methods in humanitarian emergencies include hazard, vulnerability, and risk assessments; rapid assessment and survey methods; disease distribution and outbreak investigations; planning and implementation of health information systems; data and programme integration; and programme monitoring and evaluation. The main use of GIS in these areas is to provide maps for decision-making and advocacy, which allow overlaying types of information that may not normally be linked. GIS is also used to improve data collection in the field (for example, for rapid health assessments or mortality surveys). Development of GIS methods requires further research. Although GIS methods may save resources and reduce error, initial investment in equipment and capacity building may be substantial. Especially in humanitarian emergencies, equipment and methodologies must be practical and appropriate for field use. Add-on software to process GIS data needs to be developed and modified. As equipment becomes more user-friendly and costs decrease, GIS will become more of a routine tool for humanitarian aid organisations in humanitarian emergencies, and new and innovative uses will evolve.  相似文献   
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A number of EU institutions and government committees across Europe have expressed interest in developing methods and decision-support tools to facilitate consideration of the ethical dimensions of biotechnology assessment. As part of the work conducted in the EC supported project on ethical tools (Ethical Bio-TA Tools), a number of ethical frameworks with the potential to support the work of public policy decision-makers has been characterized and evaluated. One of these potential tools is the Delphi method. The Delphi method was originally developed to assess variables that are intangible and/or shrouded in uncertainty by drawing on the knowledge and abilities of a diverse group of experts through a form of anonymous and iterative consultation. The method has hitherto been used by a diversity of practitioners to explore issues such as technology assessment, environmental planning, and public health measures. From the original (classical) Delphi, a family of Delphi-related processes has emerged. As a result of the evaluation of the various Delphi processes, it is proposed that the classical method can be further developed and applied as a form of ethical framework to assist policy-makers. Through a series of exercises and trials, an Ethical Delphi has been developed as a potential approach for characterizing ethical issues raised by the use of novel biotechnologies. Advantages and disadvantages of the method are discussed. Further work is needed to develop the procedural aspects of the Ethical Delphi method and to test its use in different cultural contexts. However, utilizing an ethical framework of this type combines the advantages of a methodical approach to capture ethical aspects with the democratic virtues of transparency and openness to criticism. Ethical frameworks such as the Ethical Delphi should contribute to better understanding of and decision-making on issues that involve decisive ethical dimensions.  相似文献   
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