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Methane emission, nitrogen excretion, and energy partitioning in Hanwoo steers fed a typical TMR diet supplemented with Pharbitis nil seeds
No full textInternational audienceTwo in vivo experiments were conducted to evaluate the potential of Pharbitis nil seeds (PA) as an anti-methanogenic additive to ruminant feed. In experiment 1, six Hanwoo steers (459.0 ± 25.8 kg) were fed either a total mixed ration (TMR; 32-d period) or TMR supplemented with PA at 5% dry matter (DM) intake (TMR-PA; 45-d period) for two consecutive periods. Fecal and urine outputs were measured in an apparent digestibility trial in both periods. Methane (CH 4 ) yield and heat energy (HE) were measured using respiratory chambers equipped with gas analyzers. In experiment 2, five rumen cannulated Holstein steers (744 ± 35 kg) were fed the same TMR or TMR-PA diets for 40 days; rumen samples were collected at 0, 1.5, and 3 h after feeding on the last day of the feeding period. In experiment 1, although there were no differences ( p > 0.05) in nutrients or gross energy intake (GEI) between the groups, an increase ( p < 0.05) in the apparent digestibility of DM (9.1%) and neutral detergent fiber (22.9%) was observed in the TMR-PA fed Hanwoo steers. Pronounced decreases ( p < 0.05) in CH 4 (g/Kg DM; 17.1%) and urinary N excretion (% N intake; 7.6%) were observed in the TMR-PA group, leading to a 14.7% increase in metabolizable energy intake (% GEI). However, only a numerical increase ( p > 0.05) in retained energy was observed due to the increase in HE loss. In experiment 2, a drastic decrease ( p < 0.05) in rumen ammonia concentration (56.3%) associated with an increased ( p = 0.091) rumen short-chain fatty acid concentration 1.5 h after feeding were observed in TMR-PA fed Holstein steers. A 26.6% increase ( p < 0.05) in the propionate proportion during the treatment period clearly reflected a shift in the ruminal H 2 sink after 3 h of feeding. A 40% reduction ( p = 0.067) in the relative abundance of rumen protozoa Entodinium caudatum was also observed. It was concluded that PA could be a natural feed additive for CH 4 and N emission abatement
Programming and Setting Up the Object Detection Algorithm YOLO to Determine Feeding Activities of Beef Cattle: A Comparison between YOLOv8m and YOLOv10m
No full textInternational audienceThis study highlights the importance of monitoring cattle feeding behavior using the YOLO algorithm for object detection. Videos of six Charolais bulls were recorded on a French farm, and three feeding behaviors (biting, chewing, visiting) were identified and labeled using Roboflow. YOLOv8 and YOLOv10 were compared for their performance in detecting these behaviors. YOLOv10 outperformed YOLOv8 with slightly higher precision, recall, mAP50, and mAP50-95 scores. Although both algorithms demonstrated similar overall accuracy (around 90%), YOLOv8 reached optimal training faster and exhibited less overfitting. Confusion matrices indicated similar patterns of prediction errors for both versions, but YOLOv10 showed better consistency. This study concludes that while both YOLOv8 and YOLOv10 are effective in detecting cattle feeding behaviors, YOLOv10 exhibited superior average performance, learning rate, and speed, making it more suitable for practical field applications
Comment les Sciences régionales abordent-elles les enjeux environnementaux ? Une analyse bibliométrique de deux décennies de publications
No full text1International audienceUsing bibliometric methods, this paper is aimed at providing an overview of Regional Science publications that address environmental issues. The analysis covers a corpus of 1,145 articles that refer to the environment in their title, abstract or keywords and published in 18 journals between 1999 and 2020. Although these publications account for only 6% of the articles published in these journals over that period, their number gradually increased. To gain a clearer picture of the environmental issues addressed, we characterise them according to whether an integrative or topical approach is adopted and by their spatial dimensions. This analytical framework is first applied by searching for specific terms in their title, keywords and abstract. The results show that both approaches are equally effective; further, these articles address intraregional or interregional environmental issues more than global environmental issues. Second, we conduct a keyword co-occurrence analysis revealing four coherent thematic article groups treating environmental issues from the perspectives of amenities and migration, governance and policy, innovation and clusters, and land use and urban sprawl. More detailed analyses of each group allowed us to refine our understanding of how environmental issues were addressed. Finally, a cross-cutting view of the four thematic groups suggests that Regional Science approaches environmental issues through spatial disparities and inequalities, spatial interactions and interdependencies, and the spatial dimension of public action. The research perspectives in each of these areas are highlighted.A partir de méthodes bibliométriques, cet article vise à fournir une vue d'ensemble des publications en Sciences régionales qui traitent des enjeux environnementaux. L'analyse porte sur un corpus de 1 145 articles faisant référence à l'environnement dans leur titre, leur résumé ou leurs mots-clés et publiés dans 18 revues entre 1999 et 2020. Bien que ces publications ne représentent que 6 % des articles publiés dans ces revues au cours de cette période, leur nombre a progressivement augmenté. Afin de mieux appréhender les enjeux environnementaux abordés, nous les distinguons en fonction du type d'approche adoptée (intégrative versus thématique) et en fonction de leurs dimensions spatiales. L’application de ce cadre analytique s’appuie d'abord sur la recherche de termes spécifiques dans les titres, mots-clés et résumés des articles du corpus. Les résultats montrent que les deux approches sont aussi présentes l'une que l'autre ; en outre, ces articles traitent davantage des enjeux environnementaux intrarégionaux ou interrégionaux que des enjeux environnementaux globaux. Dans un deuxième temps, nous effectuons une analyse de cooccurrence des mots-clés. Celle-ci révèle quatre groupes thématiques cohérents d'articles, traitant des enjeux environnementaux sous l'angle des aménités et des migrations, de la gouvernance et des politiques publiques, de l'innovation et des clusters, et de l’occupation des sols et de l'étalement urbain. Des analyses plus détaillées nous permettent d'affiner notre compréhension de la manière dont les enjeux environnementaux sont abordés au sein de chaque groupe. Enfin, une approche transversale aux quatre groupes thématiques suggère que les Sciences régionales abordent de manière spécifique les enjeux environnementaux sous l’angle des disparités et inégalités spatiales, des interactions et interdépendances spatiales et de la dimension spatiale des politiques publiques
An integrated causal framework to evaluate uplift value with an example on change in public transport supply
No full textInternational audienceMany empirical applications aim to isolate the impact of implementing new public transport on real estate uplift value. While their conclusions generally point to positive impact, due to reduction in transportation cost, the methodological framework to investigate uplift value has largely evolved over time. This paper reviews the different methodological challenges in measuring causal uplift value and proposes an adjusted parametric approach inspired from the Alonso-Muth-Mills model, returning a complex 2-D price premium function allowing for spatial heterogeneous patterns of the average treatment effect. The proposed framework also accounts for other methodological challenges underlined by literature such as spatial autocorrelation, selectivity and representativity issues, and possible anticipation effects. To illustrate the importance of methodological choices on estimation results, the framework is applied to the case of the implementation of a bus rapid transit (BRT) system in Québec City, a medium-size Canadian city, as a specific case study
From COVID-19 to ‘new normal’? Revisiting Parisian short-term rental markets and their dynamics
No full textInternational audienceThis study uses fine-grained data on Airbnb listings and their characteristics in the city of Paris to explore the disruptions associated with COVID-19 in the Airbnb business. The results show some substantial changes during the pandemic in Airbnb’s distributions of listings, booking and revenue performance, which varied across locations, COVID waves, hosts and accommodation types. The biggest shift occurred during the first national lockdown. The city centre’s advantage was reduced during the pandemic, but this decrease was quite different depending on the Airbnb hosts and users. We also observe a recovery of the short-term rental market during the post-COVID era. These findings provide valuable insights for short-term rental hosts and policymakers to better understand the pandemic-induced short-term rental disruption
Old Rules, New Drinkers: How does the New Generation of Wine Drinkers Conceptualise Old and New World Wines?
No full textInternational audienceThe presence of vines across diverse landscapes and peoples led to the production of different wine styles with a variety of sensory characteristics. In the 20th Century, these styles were sorted into Old (i.e., European) versus New World (i.e., from other continents) to facilitate communication. Geographic origin has been playing a prominent role in drinkers’ representation, but does this apply to younger generations living in an increasingly homogenised global culture? This study investigated: (i) how young consumers conceptualise wines depending on their geographic origin (Old World vs. New World); and (ii) whether their representation differs depending on their own country of birth. A total of 921 wine drinkers from seven different countries (Canada, Chile, Czech Republic, France, Sweden, Portugal and the United Kingdom) performed a word association task using either “Old World wines” (OW) or “New World wines” (NW) as inducing words. OW wines were associated with red wines from European areas with references to tradition, grape, wine process, and ancient times. NW wines were associated with American areas with references to novelty, innovation, and positive judgments. Country-specific differences also emerged: Czech consumers mainly referred to wood aspects for OW and Oceania for NW, whereas Swedes referred to sustainability for NW. Canadians referred to higher prices and aged wines for OW and globalisation for NW, and Chilean consumers referred to a superior intensity for OW. The Portuguese associated NW with conviviality, while the British associated it with positive feelings and mouthfeel perception. The numerous references to geographical origin and a persistent contrast between tradition and modernity demonstrate the transmission of wine culture from older generations to young drinkers. The specificities observed per country point to some key aspects on which the wine industry can capitalise to reconnect with young consumers
P01-34 Identification and toxicity assessment of volatile and semi-volatile non-intentionally added substances from polyester-based can coating
No full textMeeting58th Congress of the European-Societies-of-Toxicology (EUROTOX)LocationCopenhagen, DENMARKDateSEP 08-11, 2024SponsorEuropean Soc ToxicolInternational audiencePolyester based coatings are one of the technologies used in can coatings following the suspension of the intentional use of Bisphenol A (BPA) in food packaging in France. The aim of this study was to identify volatile and semi-volatile non-intentionally added substances (NIAS) from a single polyester-based formulation (5 batches) to evaluate their health risks in order to provide consumer's safety regarding consumption of canned food.Extractions and migration tests of coated metal plates were performed with acetonitrile (ACN) (incubation at 40°C for 1 day) and ethanol (EtOH) 95% (incubation at 60 °C for 10 days) in Calipack migration cells.Antioxidant degradation product 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid (CAS RN 20170-32-5), or fenozan, was identified as a NIAS and confirmed by reference standard in both ACN and EtOH 95% samples using gas chromatography–high-resolution mass spectrometry.To evaluate the toxicity of fenozan, several toxicity endpoints were investigated using different in silico quantitative structure-activity relationship predictive tools, such as Derek Nexus, Sarah Nexus, VEGAHUB software and Danish (Q)SAR Database. Positive predictions for carcinogenicity in mice, developmental toxicity, as well as several endpoints of mutagenicity, endocrine disrupting activity, and organ toxicity (hepatotoxicity and thyroid toxicity) resulted from used in silico tools.To confirm positive in silico mutagenicity alerts, fenozan was subjected to the in vitro Ames test (to test point mutation) in accordance with OECD 471 guideline, using three strains of Salmonella Typhimurium (TA100, TA98, and TA1535) and one strain of Escherichia coli (WP2) with and without metabolic activation system. A negative response was obtained in the Ames test for the four strains tested with and without metabolic activation system using direct incorporation and pre-incubation methods. Further, bioassays are required to verify the positive predictive outcomes for other toxicological endpoints to ensure the safety of polyester coatings
Les sémioses à l'épreuve de l'hybridité dans le cadre d’une formation d’ingénieurs à l’activité managériale, simulée en halle technologique
No full textInternational audienceThe present research focuses on a simulation conducted in a technology hall on aproduction line in which student engineers have to supervise professional operators. For learners, thedouble immersion in a work and training environment makes it more complex to identify what isexpected of them. They must continually discriminate in the behaviour of the facilitators what isexpected by the production manager and what is expected by the trainer. So, by exposing studentsengineers to a system of symbolic forms that is complex to interpret and understand, the didacticenvironment offered by this hybrid space is the site of continuous semiosis on their part.With reference to the Theory of Joint Action in Didactics, this research questions the ways in whichthe hibrid dimensions of the training device act as a resource or a hindrance to the understanding ofdidactic games, the acquisition of targeted skills and/or the implementation of practices expected bytrainers. Based on thirteen case studies, the results identify a number of conditions that must be metfor these hybrid dimensions to be conducive to learning.La présente recherche se centre sur une simulation conduite au sein d’une halletechnologique sur une ligne de production dans laquelle des élèves-ingénieurs doivent encadrer desopératrices professionnelles. Pour les apprenants, la double immersion dans un environnement detravail et de formation rend plus complexe l’identification de ce qui est attendu d’eux. Ils doiventcontinuellement discerner, dans le comportement des animateurs, ce qui relève soit des attentes dudirecteur de production, soit du formateur. Aussi, en exposant les élèves-ingénieurs à un système deformes symboliques complexe à lire et à comprendre, le milieu didactique proposé par cet espacehybride est-il le lieu de sémioses continuelles de leur part ?En référence à la Théorie de l’Action Conjointe en Didactique (TACD), la présente recherchequestionne la manière selon laquelle les dimensions d’hybridité du dispositif font ressource ou entrave,tant pour la lecture des jeux didactiques que pour l’acquisition des compétences visées et/ou de lamise en œuvre des pratiques attendues par les formateurs. Au travers de treize cas, les résultatsidentifient quelques conditions pour que ces dimensions d’hybridité soient propices auxapprentissages
Structural and functional characterization of nitric oxide synthases (NOS) of Klebsormidium nitens, a model alga for studying the transition from aquatic algae to terrestrial plants
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Pesticide use is affected more by crop species than by crop diversity at the cropping system level
No full textInternational audienceCrop diversification has been shown to enhance a number of ecosystem services, including the regulation of insect pest, weed and pathogen pressure, thereby reducing pesticide needs and use. However, the quantitative relationship between crop diversification at the cropping system scale and pesticide use has been rarely addressed and is mostly supported by evidence from landscape scale or a few long-term experiments. Nevertheless, crop diversification can reduce pesticide use both as a result of the use of crops with lower inherent pesticide reliance (the effect of crop species), and as a result of the pest regulation effect due to the number of different crops in the cropping system (the effect of crop diversity). These two effects combine into a net effect at the cropping system scale which can be difficult to differentiate through experimental design or a modeling approach. We employed the DEPHY network database describing 1285 cropping systems and 67 cash crops to disentangle and quantify the two complementary effects on pesticide use at the cropping system level. Our results show that crop species and crop diversity explain 37.1 % and 1.3 % of the cropping systems total pesticide usevariance respectively, while 38.7 % explained by other factors (Residuals). Excluding the crop species effect reveals that adding one crop in the cropping system decreases total pesticide use by 0.09 units of treatment frequency index, on average. Further studies are needed to shed light on the effects of crop species characteristics, as well as take into account other factors such as climate conditions