Hypothetical surveys are commonly used to elicit consumer behavior to guide product development, marketing, and labeling strategies. However, despite the prevalence of surveys in consumer food studies, previous work has not assessed the relationship between hypothetical responses and actual consumer behavior in real-world purchase situations. We explore whether attributes cited by consumers in surveys as being important to them when making decisions indeed factor into their product decision process in real-world markets. Evidence from a point of sale study of 702 pork purchasers indicates that there is a strong correspondence between hypothetical survey ratings and actual shopping behavior.

L'analyse théorique de la vulnérabilité des règles de vote aux comportements stratégi-ques montre que le caractère plus ou moins manipulable d'une règle dépend du concept d'équilibre auquel l'on se réfère. Une question cruciale est de savoir si l'on doit ou non tenir compte des possibilités qu'ont les électeurs de réagir en présence d'une menace de manipulation. Nous étudions cette question à l'aide d'une approche expérimentale. Nos résultats tendent à valider empiriquement la notion de réaction.

During their growth in vitro, promastigotes of Leishmania amazonensis undergo differentiation from complement-susceptible to complement-resistant forms. Here, we demonstrate that both forms bind comparable amounts of C3 on their surfaces, with the predominant molecule species being the haemolytically active C3b. Likewise, equivalent amounts of C9 are deposited on both forms of promastigotes. However, while C9-bearing complexes are exposed on the cell surface of resistant promastigotes, they are cryptic in the susceptible stage of the parasites. The membrane fraction of complement-resistant promastigote lysates has the ability to inhibit complement-mediated haemolysis, blocking C9, but not C3 deposition to complement-activating complexes. Moreover, the membrane fraction of complement-resistant promastigote lysates can inhibit the late steps of guinea-pig erythrocyte lysis much more efficiently than complement-susceptible ones. Our results indicate that L. amazonensis promastigotes evade complement killing by inhibiting the cytolytic pathway of the complement cascade.