A study of cannabis potency in France over a 25 years period (1992–2016)

International audienceCannabis contains a unique class of compounds known as the cannabinoids. Pharmacologically, the principal psychoactive constituent is Δ9-tetrahydrocannabinol (THC). The amount of THC in conjunction with selected additional cannabinoid compounds (cannabidiol/CBD, cannabinol/CBN), determines the strength or potency of the cannabis product. Recently, reports have speculated over the change in the quality of cannabis products, from nearly a decade, specifically concerning the increase in cannabinoid content. This article exploits the analytical data of cannabis samples analyzed in the five French forensic police laboratories over 25 years. The increase potency of both herbal and resin cannabis in France is proved through the monitoring of THC content.For cannabis resin, it has slowly risen from 1992 to 2009, before a considerable increase in the last four years (mean THC content in mid-2016 is 23% compared to 10% in 2009). For herbal cannabis, it has known three main stages of growth (mean THC content is 13% in 2015 and mid-2016 compared to 7% in 2009 and 2% in 1995). The calculation of THC/CBD ratios in both herbal and resin samples confirms the recent change in chemotypes in favor of high potency categories. Finally, the CBN/THC ratios in marijuana samples were measured in order to evaluate the freshness of French seized hemp

Identification of Volatile Compounds in Blackcurrant Berries: Differences among Cultivars

International audienceBerries of blackcurrant are known to produce a strong flavor. Some previous studieshave reported that a given cultivar of blackcurrant can produce berries with a specific profile ofvolatile compounds. For the Burgundy region in France, the Noir de Bourgogne cultivar is especiallyimportant because it is the main ingredient of a liquor with a designation of origin. The aim of thepresent study was to characterize the volatile fractions of berries from 15 cultivars in order to explorethe possibility of using different cultivars for liquor production. The plants were cultivated underthe same conditions and harvested in the same year. The volatile fractions of the harvested berrieswere analyzed using HS-SPME-GC-MS. Thorough univariate statistical analysis and multivariateanalysis were applied to the dataset, which made it possible to identify groups within cultivars. TheRosenthal cultivar exhibited a quite flat profile; the Lositkia, Ben Tiran, and Barchatnaia cultivarsshared common features; the Noir de Bourgogne cultivar showed the highest amounts of moleculessuch as 3-carene, limonene, β-phellandrene, ocimene, α-terpinolene, and bicyclogermacrene. Noneof the studied varieties were close to the Noir de Bourgogne on the basis of VOC analysis

« Si je vous dis alimentation durable » : qu’y a-t-il dans l’esprit des consommateurs ?

National audienceIntroduction et but de l'étude Il devient impératif d'adopter une alimentation durable pour préserver l'écosystème planétaire et le bien-être de ses habitants. Ainsi, les autorités publiques recommandent de plus en plus l'adoption d'une alimentation saine et durable. Les s c i e n t i f i q u e s e s s e n t i e l l e s : n u t r i t i o n n e l l e, (ADEME, 2019 ; FAO, 2010). Cependant, ce concept d'« alimentation durable » peut être difficile à comprendre pour les consommateurs. Ils pourraient avoir une compréhension partielle de ce concept, ce qui pourrait entraîner une difficulté de mise en pratique des recommandations. Caractérisent l'alimentation durable par quatre dimensions elle doit respecter l'environnement, être de bonne qualité être culturellement acceptable et économiquement équitable. L'objectif de notre étude était d'étudier les représentations mentales et les connaissances des consommateurs français concernant l'alimentation durable. Seules quelques études ont déjà été conduites en France via des entretiens (Mathe, 2009 ; Rémésy et al., 2008) et un questionnaire (European Commission, 2020). De plus, la littérature internationale a montré que la représentation de l'alimentation durable pourrait être différente selon les consommateurs. Différentes études convergent vers une segmentation des individus selon leur niveau d'études. Les personnes ayant fait des études supérieures seraient plus concernées par l'environnement et auraient plus de connaissances sur la durabilité alimentaire que les personnes n'ayant pas fait d'études supérieures (Franzen & Vogl, 2013 ; Lassoued et al., 2023 ; Panzone et al., 2016 ; Sánchez-Bravo et al., 2020 ; Van Loo et al., 2017). Nous avons donc étudié comment le niveau d'éducation pourrait i n f l u e n c e r l e s r e p r é s e n t a t i o n s me n t a l e s d e s c o n s o mma t e u r s f r a n ç a i s s u r l'alimentation durable. Matériel et méthodes Une tâche d'évocation a été réalisée auprès de 273 participants âgés de 20 à 60 ans. Cette tâche d'évocation a été suivie d'une tâche de classement et de polarité. L'expression inductive "alimentation durable" a été proposé e a u x participants. Afin de garantir la spontanéité, les participants disposaient d'un maximum de 100 secondes pour répondre à la question suivante : "Quels sont les cinq mots, expressions ou adjectifs qui vous viennent spontanément à l'esprit lorsque je dis "alimentation durable" ? Après avoir énuméré cinq évocations, les participants ont été invités à les classer selon l'importance qu'ils leur accordaient, de 1 à 5 (1 pour l'évocation que les participants considéraient comme la plus importante et 5 pour la moins importante). Enfin, les participants ont évalué la valence de leurs évocations sur une échelle de -2 à +2 : très négative (-2), négative (-1), neutre (0), positive (+1) et très positive (+2). Résultats et analyses statistiques Nos résultats ont mis en évidence des évocations communes chez les personnes interrogées, englobant les notions d'écologie, de santé, d'environnement et de local. Toutefois, les dimensions socioculturelles et économiques sont peu mentionnées comparativement à la dimension environnementale qui est prédominante. L'analyse différenciée selon le niveau d'éducation a révélé une perception plus multidimensionnelle chez les individus ayant fait des études supérieures. Conclusion Ces résultats montrent que la définition de l'alimentation durable est encore confuse et incomplète pour les consommateurs français. Clarifier le concept d'« alimentation durable » semble donc nécessaire pour améliorer la compréhension par le consommateur et ainsi favoriser une meilleure adoption de pratiques alimentaires durables

Flavor compounds in blackcurrant berries: Multivariate analysis of datasets obtained with natural variability and various experimental parameters

International audienceBerries of blackcurrant are source of vitamin C, flavonoids, beta-carotene, lutein and phenolic acid, with deep inky blue color and strong flavor. Within the works reported on blackcurrant berries, some studies suggested that a given cultivar of blackcurrant could yield berries with a specific profile in volatile compounds. However, in these studies, berries of various cultivars were obtained from different growing areas throughout the world. Moreover, methods used to study flavor compounds were different, and only few authors attempted to compare their results to other ones already published. The present review aims to highlight the most important parameters influencing the reported results concerning aroma compounds in blackcurrant berries. We conducted a complete bibliometric and meta-analysis. We collected data from published studies, taking into account parameters linked with natural variability and experimental parameters. We obtained a pool of 351 identified volatile compounds, among which about twenty molecules we considered as representative of the general volatile profile of blackcurrant berries. Collected data were analyzed first using Multiple Factor Analysis and Hierarchical Clustering on Principal Components, and then using Nonmetric MultiDimensional Scaling. We obtained mainly four consolidated clusters characterized by their richness/poorness in given volatile compounds. None of these clusters was linked with specific cultivars. Therefore, further research still has to be done to establish clearly the typicality of given cultivars that are empirically known to give specific organoleptic properties to manufactured products. Nevertheless, this study allowed identifying the important molecules to target with appropriate method and the experimental conditions to control

IRMS to study a common cocaine cutting agent: phenacetin

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Proxi-detection to monitor the growth status of wheat in the presence of weeds using low-cost and simple digital tools to track the emergence of stress

International audienceThis study combines proximal sensing technology based on a mobile visible imaging device and a dynamic ecophysiological model to estimate the growth status of two winter wheat crops (Apache and Rubisko cultivars) in the presence of uncontrolled broadleaf weeds. Working at early growth stages and on four different dates, each plot was photographed and then destructive biomass samples were collected. After calibration, crop aboveground biomass is inferred from an image indicator, the fractional vegetation cover (FVC). A supervised image classification algorithm was used to calculate FVC for crop (FVCc) and for weeds (FVCw). Analysis of FVC measurements focused on stand heterogeneity by comparing their variability and the impact of weeds on crop growth. Over time, the discrepancy between plant biomass derived from the image and data simulated from a simple ecophysiological model increased for most areas of the plot, indicating the presence of crop stress. At the same time, the weed pressure (WP) study concluded that weeds did not have a major influence on crop growth, although locally some areas showed a negative impact on crop growth. Therefore, weeds were not the major stress observed on the later dates of the study. These low-cost technologies aim to determine stress in wheat crop and support farmers in their transition to agroecology for highly accurate plot monitoring

“If I say sustainable diet”: What are French consumers’ social representations ?

International audienceThe adoption of sustainable diets is essential to maintain our planet’s ecosystem and the well-being of its inhabitants. Scientists characterize sustainable diets by four essential dimensions: respectful of the environment, of good nutritional quality, culturally acceptable, and economically fair. The ‘sustainable diet’ concept, however, can be challenging for consumers to understand. They might partially understand the concept or have representations of the concept that are not shared between individuals, which could result in difficulty putting the recommendations into practice. Our study investigated French consumers’ social representations of sustainable diets, aiming more particularly to show if groups with different levels of education might have different representations. A free word association task was carried out by 273 participants aged between 20 and 60 years. Our results revealed common associations among the participants, including concepts such as ecology, health, environment, and locality. Sociocultural and economic dimensions were rarely mentioned, unlike the predominant environmental dimension. Segmentation analysis by education level revealed that participants in the higher education group had more multidimensional social representations. These results show that the ‘sustainable diet’ concept is not fully shared by French consumers. Clarifying the definition should improve consumer understanding, thus promoting the adoption of sustainable diet practices by all

Comparaison d'échantllons de drogue basée sur la connaissance

International audienceDrug sample comparison is a process used by the French National police to identify drug distribution networks. The current approach is based on manual comparison done by forensic experts. In this article, we present our approach to acquire, formalise, and specify expert knowledge to improve the current process. For modelling the underlying knowledge we use an ontology coupled with logical rules. The different steps of our approach are designed to be reused in other application domains. The results obtained are explainable making them usable by experts in different fields

IA neuro-symbolique pour l'interprétation granulaire des données des bases STUPS© et OTARIES© : défis applicatifs et perspectives

International audienceHistoriquement, l'intelligence artificielle (IA) s'est divisée en 2 courants selon les hypothèses faites pour modéliser l'intelligence humaine : l'IA symbolique, supposant que des symboles sont nécessaires, et l'IA statistique (plus particulièrement l'IA connexionniste) affirmant le contraire. Dernièrement, l'IA neuro-symbolique tente de réconcilier les 2. Les travaux présentés dans cet article sont en en collaboration avec la Police Scientifique française, dans le contexte du Plan National Stup. Nous présentons les problématiques métiers en lien avec le projet, puis en déduisons les problématiques scientifiques. Après un rappel des domaines de l'IA et leurs limites, nous présentons un état des lieux du domaine de l'IA neuro-symbolique. Nous discutons les défis applicatifs avant de finir par une présentation des premiers travaux qui ont été conduits. Des pistes d'approches basées sur l'état des lieux de l'IA neurosymbolique sont aussi présentées pour la suite des travaux