Consumer Perception of Vegetables Resulting From Conventional Field or Greenhouse Agricultural Methods

This survey studies the way in which French consumers perceive fruits and vegetables, be they local, domestic or imported, resulting from conventional field or greenhouse agricultural methods, in terms of a health and hedonic, then a sustainability, point of view. The method employed, focus groups with individual questionnaires and the use of real-to-life scenarios, allows to get findings concerning the knowledge of the various cultivation methods, attitudes concerning these various methods, the role of information, to expose three representational profiles and, the results of the producer scenario, distributor scenario and consumer scenario study. On a general level, this study brings to light the negative image associated with greenhouse growers but consumer perception varies according to the representational profiles (Traditionalists, Spendthrifts and Responsible). ...French Abstract : Cette étude s'intéresse à la façon dont les consommateurs français perçoivent les fruits et légumes, locaux, nationaux ou importés, issus de l'agriculture conventionnelle ou de production sous serre, du point de vue de la santé, des aspects hédoniques et de la durabilité. Des focus groups complétés par des questionnaires individuels et par une étude de scénarios ont permis de mettre en évidence les niveaux de connaissance et les attitudes concernant les différentes méthodes de production, le rôle de l'information, de présenter trois profils de représentation et les réponses des consommateurs face aux scénarios producteur, distributeur et consommateur. De façon générale, cette étude montre que l'image associée à la production sous serre est négative, mais les perceptions varient selon les profils de représentations (Traditionalistes, Economes, Responsables).SUSTAINABILITY; CONSUMER; FOOD CONSUMPTION; SCENARIOS METHOD; FOCUS GROUPS; AGRICULTURAL PRODUCTION METHODS; DURABILITE; CONSOMMATEUR; CONSOMMATION ALIMENTAIRE; METHODE DES SCENARIOS; METHODES DE PRODUCTION AGRICOLES

Binary Black Holes in Dense Star Clusters: Exploring the Theoretical Uncertainties

Recent N-body simulations predict that large numbers of stellar black holes (BHs) could remain bound to globular clusters (GCs) at present, and merging BH--BH binaries are produced dynamically in significant numbers. We systematically vary "standard" assumptions made by numerical simulations related to, e.g., BH formation, stellar winds, binary properties of high-mass stars, and IMF within existing uncertainties, and study the effects on the evolution of the structural properties of GCs, and the BHs in GCs. We find that variations in initial assumptions can set otherwise identical initial clusters on completely different evolutionary paths, significantly affecting their present observable properties, or even affecting the cluster's very survival to the present. However, these changes usually do not affect the numbers or properties of local BH--BH mergers. The only exception is that variations in the assumed winds and IMF can change the masses and numbers of local BH--BH mergers, respectively. All other variations (e.g., in initial binary properties and binary fraction) leave the masses and numbers of locally merging BH--BH binaries largely unchanged. This is in contrast to binary population synthesis models for the field, where results are very sensitive to many uncertain parameters in the initial binary properties and binary stellar-evolution physics. We find that weak winds are required for producing GW150914-like mergers from GCs at low redshifts. LVT151012 can be produced in GCs modeled both with strong and weak winds. GW151226 is lower-mass than typical mergers from GCs modeled with weak winds, but is similar to mergers from GCs modeled with strong winds.Comment: 25 pages, 20 figures, 4 tables, ApJ in pres