53 research outputs found

    Estimates of DNA damage by the comet assay in the direct-developing frog Eleutherodactylus johnstonei (Anura, Eleutherodactylidae)

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    The aim of this study was to use the Comet assay to assess genetic damage in the direct-developing frog Eleutherodactylus johnstonei. A DNA diffusion assay was used to evaluate the effectiveness of alkaline, enzymatic and alkaline/enzymatic treatments for lysing E. johnstonei blood cells and to determine the amount of DNA strand breakage associated with apoptosis and necrosis. Cell sensitivity to the mutagens bleomycin (BLM) and 4-nitro-quinoline-1-oxide (4NQO) was also assessed using the Comet assay, as was the assay reproducibility. Alkaline treatment did not lyse the cytoplasmic and nuclear membranes of E. johnstonei blood cells, whereas enzymatic digestion with proteinase K (40 μg/mL) yielded naked nuclei. The contribution of apoptosis and necrosis (assessed by the DNA diffusion assay) to DNA damage was estimated to range from 0% to 8%. BLM and 4NQO induced DNA damage in E. johnstonei blood cells at different concentrations and exposure times. Dose-effect curves with both mutagens were highly reproducible and showed consistently low coefficients of variation (CV ≤ 10%). The results are discussed with regard to the potential use of the modified Comet assay for assessing the exposure of E. johnstonei to herbicides in ecotoxicological studies

    How Techniques of Neutralization Legitimize Norm- and Attitude-Inconsistent Consumer Behavior

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    In accordance with societal norms and values, consumers readily indicate their positive attitudes towards sustainability. However, they hardly take sustainability into account when engaging in exchange relationships with companies. To shed light on this paradox, this paper investigates whether defense mechanisms and the more specific concept of neutralization techniques can explain the discrepancy between societal norms and actual behavior. A multi-method qualitative research design provides rich insights into consumers' underlying cognitive processes and how they make sense of their attitude-behavior divergences. Drawing on the Ways Model of account-taking, which is advanced to a Cycle Model, the findings illustrate how neutralization strategies are used to legitimize inconsistencies between norm-conforming attitudes and actual behavior. Furthermore, the paper discusses how the repetitive reinforcement of neutralizing patterns and feedback loops between individuals and society are linked to the rise of anomic consumer behavior
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