Enrolling study personnel in Ebola vaccine trials: from guidelines to practice in a non-epidemic context.

BACKGROUND: Enrolling participants in clinical trials can be challenging, especially with respect to prophylactic vaccine trials. The vaccination of study personnel in Ebola vaccine trials during the 2014-2016 epidemic played a crucial role in inspiring trust and facilitating volunteer enrollment. We evaluated the ethical and methodological considerations as they applied to an ongoing phase 2 randomized prophylactic Ebola vaccine trial that enrolled healthy volunteers in Guinea, Liberia, Sierra Leone, and Mali in a non-epidemic context. METHODS: On the assumption that the personnel on site involved in executing the protocol, as well as community mobilizers (not involved in the on-site procedures), might also volunteer to enter the trial, we considered both ethical and methodological considerations to set clear rules that can be shared a priori with these persons. We reviewed the scientific and gray literature to identify relevant references and then conducted an analysis of the ethical and methodological considerations. RESULTS: There are currently no regulations preventing a clinical investigator or site staff from participating in a trial. However, the enrollment of personnel raises the risk of undue influence and challenges the basic ethical principle of voluntary participation. The confidentiality of personal medical information, such as HIV test results, may also be difficult to ensure among personnel. There is a risk of disruption of trial operations due to the potential absence of the personnel for their commitment as trial participants, and there is also a potential for introducing differential behavior of on-site staff as they obtain access to accumulating information during the trial (e.g., the incidence of adverse events). Blinding could be jeopardized, given knowledge of product-specific adverse event profiles and the proximity to unblinded site staff. These aspects were considered more relevant for on-site staff than for community mobilizers, who have limited contact with site staff. CONCLUSION: In a non-epidemic context, ethical and methodological considerations limit the collective benefit of enrolling site staff in a vaccine trial. These considerations do not apply to community mobilizers, whose potential enrollment should be considered as long as they meet the inclusion criteria and they are not exposed to any form of coercion

Myoconductive and osteoinductive free-standing polysaccharide membranes

Free-standing (FS) membranes have increasing applications in the biomedical field as drug delivery systems for wound healing and tissue engineering. Here, we studied the potential of free-standing membranes made by the layer-by-layer assembly of chitosan and alginate to be used as a simple biomimetic system of the periosteum. The design of a periosteum-like membrane implies the elaboration of a thick membrane suitable for both muscle and bone formation. Our aim was to produce well-defined ∼50 μm thick polysaccharide membranes that could be easily manipulated, were mechanically resistant, and would enable both myogenesis and osteogenesis in vitro and in vivo. The membranes were chemically crosslinked to improve their mechanical properties. Crosslinking chemistry was followed via Fourier transform infrared spectroscopy and the mechanical properties of the membranes were assessed using dynamic mechanical analysis. The loading and release of the potent osteoinductive growth factor bone morphogenetic protein 2 (BMP-2) inside and outside of the FS membrane was followed by fluorescence spectroscopy in a physiological buffer over 1 month. The myogenic and osteogenic potentials of the membranes in vitro were assessed using BMP-2-responsive skeletal myoblasts. Finally, their osteoinductive properties in vivo were studied in a preliminary experiment using a mouse ectopic model. Our results showed that the more crosslinked FS membranes enabled a more efficient myoblast differentiation in myotubes. In addition, we showed that a tunable amount of BMP-2 can be loaded into and subsequently released from the membranes, depending on the crosslinking degree and the initial BMP-2 concentration in solution. Only the more crosslinked membranes were found to be osteoinductive in vivo. These polysaccharide-based membranes have strong potential as a periosteum-mimetic scaffold for bone tissue regeneration.This work was financially supported by the Foundation for Science and Technology (FCT) through the scholarship SFRH/BPD/96797/2013, Fundo Social Europeu (FSE), and Programa Diferencial de Potencial Human (POPH) granted to Sofia G. Caridade. C.M. is indebted to the Association Francaise contre les Myopathies for financial support via a post-doctoral fellowship (AFM project 16673). J.A. acknowledges the Whitaker International Fellows and Scholars Program for support via a post-doctoral fellowship. This work was supported by the European Commission (FP7 program) via a European Research Council starting grant (BIOMIM, GA 259370 to C.P.) and by the AFM (grant Microtiss, 16530). We thank Isabelle Paintrand for her technical help with the confocal apparatus

Free-standing polyelectrolyte membranes made of chitosan and alginate

Free-standing films have increasing applications in the biomedical field as drug delivery systems for wound healing and tissue engineering. Here, we prepared free-standing membranes by the layer-by-layer assembly of chitosan and alginate, two widely used biomaterials. Our aim was to produce a thick membrane and to study the permeation of model drugs and the adhesion of muscle cells. We first defined the optimal growth conditions in terms of pH and alginate concentration. The membranes could be easily detached from polystyrene or polypropylene substrate without any postprocessing step. The dry thickness was varied over a large range from 4 to 35 μm. A 2-fold swelling was observed by confocal microscopy when they were immersed in PBS. In addition, we quantified the permeation of model drugs (fluorescent dextrans) through the free-standing membrane, which depended on the dextran molecular weight. Finally, we showed that myoblast cells exhibited a preferential adhesion on the alginate-ending membrane as compared to the chitosan-ending membrane or to the substrate side.This work was financially supported by Foundation for Science and Technology (FCT) through the Scholarship SFRH/BD/64601/2009 granted to S.G.C. C.M. is indebted to Grenoble INP for financial support via a postdoctoral fellowship. This work was supported by the European Commission (FP7 Program) via a European Research Council starting grant (BIOMIM, GA 259370 to C.P.). C.P. is also grateful to Institut Universitaire de France and to Grenoble Institute of Technology for financial support. We thank Isabelle Paintrand for her technical help with the confocal apparatus and Patrick Chaudouet for his help with SEM imaging

Les décisions individuelles d'adaptation aux inondations : le cas de résidents en zones inondables dans le Sud de la France

In France, one in four inhabitants is exposed to floods. In this thesis, we studied the mechanisms that lead individuals to adapt to these natural risks. More specifically, we examined the influence of the characteristics of individuals and their situations relating to risks on their adaptation decisions. To do so, we conducted a quantitative survey of 331 inhabitants of flood-prone areas in the South of France. To design the questionnaire used in the quantitative survey, we relied on the literature and on the analysis of an exploratory qualitative survey. According to our results, the appraisal of the threat posed by floods and the perception of the severity of past experiences of such disasters have a positive effect on adaptation intentions, as described in the Protection Motivation Theory (Grothmann and Reusswig, 2006). Our results also suggest the existence of a negative feedback effect of past adaptation decisions on the appraisal of the threat posed by floods. Consequently, caution should be taken when interpreting the observed relations between perceptions and past adaptation decisions. Moreover, our results show a positive relation between indicators of the frequency and severity of floods and the respondents' perceptions of these features. Since these perceptions have a positive effect on the intention to adapt, it implies that the individuals who face the most frequent and severe floods are the most likely to adapt to these risks in our sample. We also examined the relations between perceptions and attitudes in the domains of financial and flood risks and studied the influence of these variables on individual adaptation to floods. To do so, we used the financial subscale of the DOSPERT psychometric scale (Weber et al., 2002; Blais and Weber, 2006) and developed a new subscale following this model, but relating to flood risks. The new subscale has acceptable internal and external consistencies. The analysis of the data collected using the flood and financial risks subscales suggests that these two types of risks tend to compete with each other. Hence, the importance granted by the respondents to financial risks compared to flood risks seems to have a negative effect on their adaptation intentions. Consequently, precautionary measures cannot be treated as types of self-insurance, which reduce only the risk of financial loss. Thus, our results suggest that individual adaptation to floods depends in particular on people's perceptions and attitudes regarding financial and flood risks, but also on their perceptions regarding the measures that can be taken to adapt to floods. According to the social amplification of risk framework (Kasperson et al., 1988), perceptions and attitudes can be modified by the first-hand or indirect experience of a risk. Our results support the hypothesis that first-hand flood experience changes attitudes and perceptions, not only in the flood domain, but also in the financial domain. To examine the role of indirect experience of floods on individual adaptation, we designed a theoretical model. It describes the relations between the components which can be taken into account to study the diffusion of an adaptation measure within a social network. In particular, social interactions are represented in this model.En France, un habitant sur quatre est exposé aux inondations. Dans cette thèse, nous nous sommes donc intéressés aux mécanismes de l'adaptation individuelle à ces risques naturels. Plus précisément, nous avons examiné l'influence des caractéristiques des individus et de leurs situations par rapport aux risques sur leurs décisions d'adaptation. Pour ce faire, nous avons mené une enquête quantitative auprès de 331 personnes résidant en zone inondable dans les départements de l'Aude et du Var. Le questionnaire utilisé lors de cette enquête a été développé à partir de la littérature et de l'analyse d'une enquête exploratoire par entretiens semi-directifs. D'après nos résultats, la perception de la menace liée aux inondations et la perception de la gravité de l'inondation vécue ont un effet positif sur les intentions d'adaptation, comme décrit dans la Protection Motivation Theory adaptée au domaine des inondations (Grothmann et Reusswig, 2006). Nos résultats suggèrent également l'existence d'une rétroaction négative de la mise en place d'une mesure de prévention sur la perception de la menace liée aux inondations. Cela invite à considérer avec prudence les relations observées empiriquement entre les perceptions et les décisions d'adaptation passées. De plus, nos résultats montrent une relation positive entre des indicateurs de la fréquence et de la sévérité des inondations et les perceptions de ces caractéristiques par les répondants. Comme ces perceptions ont un effet positif sur l'intention de s'adapter, cela signifie que les personnes les plus susceptibles de s'adapter sont celles qui sont exposées aux inondations les plus sévères et fréquentes dans l'échantillon étudié. Nous avons aussi examiné les relations entre les perceptions et les attitudes dans les domaines des risques financiers et d'inondation et étudié l'influence de ces variables sur l'adaptation individuelle. Pour ce faire, nous avons utilisé la sous-échelle psychométrique concernant les risques financiers de l'échelle DOSPERT (Weber et al., 2002; Blais et Weber, 2006) et développé une sous-échelle psychométrique sur le même modèle, mais qui concerne les risques d'inondation. Cette dernière présente des cohérences interne et externe satisfaisantes. L'analyse des données récoltées en utilisant les sous-échelles des domaines des risques financiers et d'inondation suggère que ces deux types de risques ont tendance à entrer en compétition. Ainsi, l'importance accordée par les individus aux risques financiers par rapport aux risques d'inondation semble avoir un effet négatif sur les intentions d'adaptation. En conséquence, les mesures de prévention ne peuvent pas être considérées comme des formes d'auto-assurance, qui permettent de réduire uniquement les risques de pertes financières. Ainsi, nos résultats suggèrent que l'adaptation individuelle dépend notamment des perceptions et attitudes des individus en ce qui concerne les risques financiers, les risques d'inondation, mais aussi de leurs perceptions concernant les moyens d'adaptation aux inondations. Or, d'après la théorie de l'amplification sociale du risque (Kasperson et al., 1988), les perceptions et attitudes peuvent être modifiées par l'expérience directe ou indirecte d'un risque. Nos résultats corroborent l'hypothèse selon laquelle le fait d'avoir vécu une inondation modifie les perceptions et attitudes non seulement dans le domaine des risques d'inondation, mais aussi dans celui des risques financiers. Pour examiner l'influence de l'expérience indirecte des inondations sur l'adaptation individuelle, nous avons développé un modèle théorique qui décrit les relations entre les composantes à considérer pour étudier la diffusion d'un moyen d'adaptation au sein d'un réseau social. Ce modèle prend notamment en compte les interactions sociales

Individual adaptation decisions to floods : the case of residents of flood-prone areas in the South of France

En France, un habitant sur quatre est exposé aux inondations. Dans cette thèse, nous nous sommes donc intéressés aux mécanismes de l'adaptation individuelle à ces risques naturels. Plus précisément, nous avons examiné l'influence des caractéristiques des individus et de leurs situations par rapport aux risques sur leurs décisions d'adaptation. Pour ce faire, nous avons mené une enquête quantitative auprès de 331 personnes résidant en zone inondable dans les départements de l'Aude et du Var. Le questionnaire utilisé lors de cette enquête a été développé à partir de la littérature et de l'analyse d'une enquête exploratoire par entretiens semi-directifs. D'après nos résultats, la perception de la menace liée aux inondations et la perception de la gravité de l'inondation vécue ont un effet positif sur les intentions d'adaptation, comme décrit dans la Protection Motivation Theory adaptée au domaine des inondations (Grothmann et Reusswig, 2006). Nos résultats suggèrent également l'existence d'une rétroaction négative de la mise en place d'une mesure de prévention sur la perception de la menace liée aux inondations. Cela invite à considérer avec prudence les relations observées empiriquement entre les perceptions et les décisions d'adaptation passées. De plus, nos résultats montrent une relation positive entre des indicateurs de la fréquence et de la sévérité des inondations et les perceptions de ces caractéristiques par les répondants. Comme ces perceptions ont un effet positif sur l'intention de s'adapter, cela signifie que les personnes les plus susceptibles de s'adapter sont celles qui sont exposées aux inondations les plus sévères et fréquentes dans l'échantillon étudié. Nous avons aussi examiné les relations entre les perceptions et les attitudes dans les domaines des risques financiers et d'inondation et étudié l'influence de ces variables sur l'adaptation individuelle. Pour ce faire, nous avons utilisé la sous-échelle psychométrique concernant les risques financiers de l'échelle DOSPERT (Weber et al., 2002; Blais et Weber, 2006) et développé une sous-échelle psychométrique sur le même modèle, mais qui concerne les risques d'inondation. Cette dernière présente des cohérences interne et externe satisfaisantes. L'analyse des données récoltées en utilisant les sous-échelles des domaines des risques financiers et d'inondation suggère que ces deux types de risques ont tendance à entrer en compétition. Ainsi, l'importance accordée par les individus aux risques financiers par rapport aux risques d'inondation semble avoir un effet négatif sur les intentions d'adaptation. En conséquence, les mesures de prévention ne peuvent pas être considérées comme des formes d'auto-assurance, qui permettent de réduire uniquement les risques de pertes financières. Ainsi, nos résultats suggèrent que l'adaptation individuelle dépend notamment des perceptions et attitudes des individus en ce qui concerne les risques financiers, les risques d'inondation, mais aussi de leurs perceptions concernant les moyens d'adaptation aux inondations. Or, d'après la théorie de l'amplification sociale du risque (Kasperson et al., 1988), les perceptions et attitudes peuvent être modifiées par l'expérience directe ou indirecte d'un risque. Nos résultats corroborent l'hypothèse selon laquelle le fait d'avoir vécu une inondation modifie les perceptions et attitudes non seulement dans le domaine des risques d'inondation, mais aussi dans celui des risques financiers. Pour examiner l'influence de l'expérience indirecte des inondations sur l'adaptation individuelle, nous avons développé un modèle théorique qui décrit les relations entre les composantes à considérer pour étudier la diffusion d'un moyen d'adaptation au sein d'un réseau social. Ce modèle prend notamment en compte les interactions sociales.In France, one in four inhabitants is exposed to floods. In this thesis, we studied the mechanisms that lead individuals to adapt to these natural risks. More specifically, we examined the influence of the characteristics of individuals and their situations relating to risks on their adaptation decisions. To do so, we conducted a quantitative survey of 331 inhabitants of flood-prone areas in the South of France. To design the questionnaire used in the quantitative survey, we relied on the literature and on the analysis of an exploratory qualitative survey. According to our results, the appraisal of the threat posed by floods and the perception of the severity of past experiences of such disasters have a positive effect on adaptation intentions, as described in the Protection Motivation Theory (Grothmann and Reusswig, 2006). Our results also suggest the existence of a negative feedback effect of past adaptation decisions on the appraisal of the threat posed by floods. Consequently, caution should be taken when interpreting the observed relations between perceptions and past adaptation decisions. Moreover, our results show a positive relation between indicators of the frequency and severity of floods and the respondents' perceptions of these features. Since these perceptions have a positive effect on the intention to adapt, it implies that the individuals who face the most frequent and severe floods are the most likely to adapt to these risks in our sample. We also examined the relations between perceptions and attitudes in the domains of financial and flood risks and studied the influence of these variables on individual adaptation to floods. To do so, we used the financial subscale of the DOSPERT psychometric scale (Weber et al., 2002; Blais and Weber, 2006) and developed a new subscale following this model, but relating to flood risks. The new subscale has acceptable internal and external consistencies. The analysis of the data collected using the flood and financial risks subscales suggests that these two types of risks tend to compete with each other. Hence, the importance granted by the respondents to financial risks compared to flood risks seems to have a negative effect on their adaptation intentions. Consequently, precautionary measures cannot be treated as types of self-insurance, which reduce only the risk of financial loss. Thus, our results suggest that individual adaptation to floods depends in particular on people's perceptions and attitudes regarding financial and flood risks, but also on their perceptions regarding the measures that can be taken to adapt to floods. According to the social amplification of risk framework (Kasperson et al., 1988), perceptions and attitudes can be modified by the first-hand or indirect experience of a risk. Our results support the hypothesis that first-hand flood experience changes attitudes and perceptions, not only in the flood domain, but also in the financial domain. To examine the role of indirect experience of floods on individual adaptation, we designed a theoretical model. It describes the relations between the components which can be taken into account to study the diffusion of an adaptation measure within a social network. In particular, social interactions are represented in this model

The determinants of households' flood mitigation decisions in France-on the possibility of feedback effects from past investments

2016-11In this paper, we focus on a decomposition property recently introduced in the inequality literature and known as the weak decomposition. Such a property provides interesting analyses by allowing one to separate the within-group contribution to total inequality from the between-group contribution. A limitation of the current method of decomposition is that, depending on the structure–absolute, relative, compromise–of the inequality index, specific weights have to be used. To avoid such a problem, we propose a unique decomposition property where the weighting functions depend on the size of the population and the mean income. This allows us to characterize a large family of weakly decomposable inequality indices without any recourse to implicit invariance value judgments.Dans cet article, nous étudions les déterminants de la lutte individuelle contre les inondations en France. Nous avons mené une enquête auprès de 331 habitants de deux zones inondables et recueilli des données sur plusieurs questions, comme l’atténuation individuelle contre les inondations, la perception du risque, l’expérience du risque, et les caractéristiques socio-démographiques. Nous estimons des modèles de choix discrets pour expliquer les mesures de précaution mises en place par le ménage, et aussi l’intention de prendre de telles mesures. Nous testons la robustesse de la Protection Motivation Theory (PMT) en France ; nous discutons de son champ d’application et nous questionnons l’existence d’effets de rétroaction des investissements passés sur les intentions de protection. Nos résultats confirment que la PMT est un cadre pertinent pour décrire les mécanismes de lutte contre les inondations privée en France, en soulignant en particulier l’importance de l’évaluation de la menace, de l’expérience de la menace, et de l’adaptation. Certaines caractéristiques socio-démographiques sont également importantes pour expliquer l’atténuation privée des inondations. Nos résultats corroborent aussi la présence d’effets de rétroaction, qui suggèrent que la mise en place de mesures de précaution réduit la perception du risque d’inondation. L’existence de ces effets de rétroaction implique que les mesures envisagées, plutôt que celles mises en œuvre, devraient être examinées pour explorer davantage les déterminants de la lutte privée contre les inondation

The determinants of households' flood mitigation decisions in France - on the possibility of feedback effects from past investments

International audienceIn this paper, we investigate the determinants of private flood mitigation in France. We conducted a survey among 331 inhabitants of two flood-prone areas and collected data on several topics, including individual flood mitigation, risk perception, risk experience, and sociodemographic characteristics. We estimate discrete choice models to explain either the precautionary measures taken by the household, or the intention to undertake such measures in the future. Our results confirm that the Protection Motivation Theory is a relevant framework to describe the mechanisms of private flood mitigation in France, highlighting in particular the importance of threat appraisal and previous experience of floods. Some sociodemographic features also play a significant role in explaining private flood mitigation. We also observed that respondents who had already taken precautionary measures have a lower perception of the risk of flooding than respondents who planned to implement such measures at the time of the survey. This result can be explained by the existence of a feedback effect of having taken precautionary measures on risk perception. If subsequent studies support this assumption, it would imply that intended measures, rather than implemented ones, should be examined to explore further the determinants of private flood mitigation

Community acceptance of biodiversity offsets: evidence from a choice experiment

This study of the community’s acceptance of biodiversity offsets in Australia provides insights relevant to future revisions of offset policies of both State and Commonwealth Governments. A choice experiment was used to measure preferences for the general acceptability of offsetting, and for a number of attributes that define how an offset can be implemented. Based on a sample of 204 respondents from Perth, WA, we found that the majority of respondents did not object to the practice of biodiversity offsetting in general. A minority of respondents preferred that offset actions be direct, but most accepted a combination of direct and indirect actions. Individuals generally preferred that the offset be located near the site of impact, and it became more unacceptable the further away that it was located. However, there was heterogeneity in preferences for protecting the impacted species or a more endangered one

A model of the effects of social interactions and risk experience on adaptation behaviours

We propose a micro economic model that aims to describe how individuals choose to adopt or not a protection measure against a risk by taking into account people's experience of the risk and the social interactions. It is derived from a dynamic aggre- gate model that explains the evolution of the adoption rate of a protection measure within a population [6]. Some behavioural implications of the micro economic model are presented. In particular, we show that the aggregate model can be explained by heterogeneous and sometimes unintuitive individual decision-making processes. Especially, our model implies that the expected loss has a positive effect on the utility of agents who were not previously protected and that the utility of adaptation of people who renew a protection behaviour increases with the price of the measure. We nally discuss the empirical testability of the mode