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Vacuum pyrolysis of olive pomace for biochar production: Enhancing carbon stability and soil nutrient supply
No full textInternational audienceOlive pomace (OP), a significant agro-industrial byproduct in Mediterranean countries, poses considerable disposal challenges and offers potential as a feedstock for engineered biochar production. Conventional pyrolysis of OP has been widely studied and often yields biochar with limited aromaticity and variable nutrient content. However, no prior work has explored the potential of vacuum pyrolysis for this residue. Addressing this research gap, this study investigates the use of vacuum pyrolysis (500 °C, 15–20 kPa, 2 h) to transform OP into a stable and nutrient-rich biochar. The process yielded 30.9 wt.% biochar with 68.7 % fixed carbon, representing an improvement of 20 % in carbon retention compared with atmospheric pyrolysis. Elemental ratios (H/C = 0.03 and O/C = 0.18) confirmed high aromaticity and long-term stability, while mineral enrichment underscored high agronomic value. The biochar displayed a cation exchange capacity of 56.2 cmolc/kg and 79 % porosity, properties favorable for nutrient cycling, and soil remediation. The carbon sequestration potential was estimated at 2.6 tCO₂eq per ton of biochar applied and heavy metals were below international thresholds, ensuring environmental safety. Beyond material characterization, the work highlights engineering advantages, including reduced inert gas requirements and a reusable syngas fraction (64.6 wt.%) that can offset energy costs. However, as the study was conducted at a single pressure level, the specific contribution of vacuum conditions requires further confirmation through multi-pressure trials. Such results position vacuum pyrolysis as a promising technology for waste valorization, carbon management, and climate-smart agriculture, while future research should address field validation, contaminant screening, and life-cycle performance
From policy to practice in cervical cancer prevention in Reunion Island
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L'accès à une alimentation satisfaisante sur le territoire de Montreuil en Seine-Saint-Denis
No full textInternational audienceLa question alimentaire sur les territoires croise d’un côté le développement de nombreuses initiatives relevant de systèmes alimentaires alternatifs (Amap, circuits-courts, coopératives de consommation, etc.) et de l’autre, une augmentation du nombre de personnes en situation de précarité alimentaire, associée à des préoccupations croissantes de santé publique (obésité, maladies cardio-vasculaires, dénutrition). Dans cette tension, les collectivités territoriales sont sollicitées pour soutenir des alternatives (des circuits-courts, des boucles alimentaires vertueuses, etc.) et pour lutter contre l’aggravation de laprécarité alimentaire. Elles sont, de fait, confrontées à des difficultés pour porter une politique alimentaire visant l’accessibilité de toutes et tous à une alimentation satisfaisante, qui soit de bonne qualité gustative, choisie, tout en assurant un revenu décent aux agriculteurs et en étant respectueuse de l’environnement. Dans ce contexte, nous étudions la stratégie alimentaire de la Ville de Montreuil, dans la banlieue est parisienne. Le territoire montreuillois se caractérise par un milieu urbain dense, une faible autonomie en matière de production agricole et une importante précarité alimentaire. Les enjeux agricoles et alimemtaires occupent une place particulière au sein d’un tissu associatif par ailleurs très dense. Ce chapitre examine les résultats de la recherche participa-tive « Construire un projet alimentaire citoyen sur un territoire urbain :initiatives pour une alimentation durable et accessible à Montreuil » (COPALIM). COPALIM s’appuie sur un partenariat entre une collectivité territoriale qui souhaite mettre en place une stratégie alimentaire sur le territoire, des acteurs issus de l’économie sociale et solidaire, des acteurs de l’accompagnement social et des laboratoires de recherche.La question de recherche a porté au départ sur la question de l’accès à une alimentation durable pour évoluer vers un questionnement sur l’accès à une alimentation satisfaisante dans un contexte marqué par une importante précarité alimentaire. La première partie de ce chapitre présente les enjeux théoriques de l’accès à l’alimentation durable et lescaractéristiques participatives de cette recherche. La seconde partie présente les résultats de l’enquête menée dans ce cadre en matière d’accès à l’alimentation des publics confrontés à de multiples fragilités et les réponses existantes à ces situations sur le territoire de Montreuil
Mission accomplished? A post-assessment of EU ETS impact on power sector emissions reduction
No full textInternational audienceThe debate on the capacity of the European Union Emissions Trading System (EU ETS) to effectively induce CO emissions reduction is still ongoing. This is particularly noteworthy in the case of the power sector, where numerous decarbonization policies overlap. This paper contributes to this discussion by leveraging a methodological approach that circumvents the challenges of constructing credible counterfactuals for causal inference and allows for disentangling the impact of the EU ETS from other measures on the power sector’s abatement efforts, alongside influencing factors such as weather. Specifically, we employ a Bayesian structural time series (BSTS) model, conceptually related to synthetic control techniques, to assess the effectiveness of the three completed phases of the EU ETS (2005-2020) in reducing CO emissions in the power sector across 24 Member States. We analyze the policy implementation effect over the course of each phase by comparing actual power sector emissions with counterfactual estimates derived from contemporaneous predictors related to such emissions. The results indicate a statistically significant emissions reduction in the second and third phases, with no significant reduction in the first phase. The power sector’s centrality to the EU ETS, and its critical role in our economies emphasize the importance of our findings in evaluating emissions reduction objectives
Real-life impact of clinical metagenomics in the intensive care unit: a multicenter retrospective study in greater paris area hospitals
No full textInternational audienceBackground: Infection are the leading cause of intensive care unit (ICU) admission, yet conventional microbiological methods frequently fail to identify the causative pathogen. Metagenomic next-generation sequencing (mNGS) is an emerging, unbiased, pan-pathogen diagnostic tool. However, its real-world microbiological and clinical impact in the ICU remains poorly characterized. This study aimed to assess the microbiological yield and clinical impact of mNGS when implemented in routine ICU practice.Methods: This retrospective multicenter study was conducted across ten tertiary-care ICUs in the Greater Paris area between January 2018 and April 2024. All patients for whom an mNGS analysis was requested by clinicians from a microbiological sample were included. Any additional pathogens identified by mNGS were independently classified as causative, possibly causative, or non-causative by two reviewers. The independent reviewers also categorised therapeutic changes attributable to mNGS as escalation, de-escalation, discontinuation, or other decision support. Discrepancies were adjudicated by a third reviewer.Results: A total of 144 mNGS analyses were performed in 132 critically ill patients (median age 55 years), 31% of whom were immunocompromised. The number of mNGS analyses requested increased each year. The most common sample types were cerebrospinal fluid (CSF) (n = 60/144, 41.7%) and pleural fluid (n = 21/144, 14.6%). Pathogens were identified by mNGS in 58 samples (40.3%), with a higher yield in pleural fluid (n = 11/21, 52.4%) than in CSF (n = 16/60, 26.6%). Of the 107 pathogens identified, 43 (40.2%) were detected exclusively by mNGS, notably anaerobic bacteria in pleural fluid and abscess samples. mNGS identified an additional pathogen in 34 cases (25.8%) of the 132 patients included, which was deemed causative in 18 cases (13.6%). mNGS findings influenced therapeutic management in seven patients (5.3%) including five cases of antibiotic de-escalation, one appropriate antibiotic escalation, and one case of clinical decision support.Conclusion: In this real-life ICU cohort, mNGS identified additional pathogens in 25.8% of patients, deemed causative in 18 cases (13.6%), and a direct therapeutic impact was observed in 5.3% of cases. However, the median turnaround time of 14 days likely limited its clinical impact. Further studies are needed to better define the role of mNGS in the diagnostic management of critically ill patients
A Bench Evaluation of the Effects of Circuit Configurations on Instrumental Dead Space During Home Mechanical Ventilation
No full textInternational audienceBackground: A number of circuit configurations can be proposed for implementing mechanical ventilation, most of which are likely to impact the instrumental dead space and thus, on alveolar ventilation. This bench study was designed to investigate the effects of circuit configuration on P CO 2 with constant ventilator settings ( iso-V T condition; V T : tidal volume ) and to evaluate the modifications of V T required to maintain stable alveolar ventilation with each circuit configuration ( iso- P ET CO 2 condition ; end-tidal CO 2 partial pressure being considered as a surrogate for alveolar ventilation). Methods: A total of 17 configurations were evaluated, including valve and leak circuits, heater humidifier or different heat and moisture exchangers, with or without catheter mount, and both invasive and noninvasive situations. All these evaluations were performed at 2 different respiratory rate, both in iso-V T and iso- P ET CO 2 conditions. Results: With valve circuits, modifications of instrumental dead space resulted in P ET CO 2 variations reaching up to 16 mm Hg from one configuration to another. The corresponding increase in the required V T to compensate for the additional dead space reached up to 120 mL. Leak circuits significantly reduced the effects of instrumental dead space compared with valve circuits. Conclusions: Any modification of the circuit configuration requires a systematic reevaluation of ventilation efficiency
Analyse didactique de la pertinence d’un dispositif de formation visant à développer une démarche réflexive chez les professeurs des écoles stagiaires
No full textInternational audienceThe main aim of this research article is to demonstrate the relevance and appropriateness of a classroom visit by a trainee primary school teacher in France. The visit is structured around three phases: observation by a trainer of the implementation of a situation by a trainee primary school teacher, post-observation interview, production of a post-interview reflective piece of writing. The methodology is based, on the one hand, on the analysis of the interview that follows the classroom observation and, on the other, on the study of the professional writing drafted by the trainee. Throughout the analysis of the system, the aim is to detect changes in the trainee teacher's posture, and thus to highlight the trainee's ability to adopt a reflective posture in terms of how he or she brings his or her pupils to experience a mathematical situation.Cet article de recherche a pour principale finalité de montrer la pertinence et la cohérence d’un dispositif spécifique de visite en classe d’un enseignant stagiaire au primaire. Ce dispositif s’articule en trois temps : observation par un formateur de la mise en œuvre d’une situation mathématique par un professeur des écoles stagiaire, entretien post-observation, production d’un écrit réflexif post-entretien. La méthodologie repose d’une part sur l’analyse de l’entretien qui fait suite à l’observation de classe, d’autre part sur l’étude de l’écrit professionnel rédigé par le stagiaire. Il s’agit tout au long de l’analyse du dispositif de déceler les changements d’attitude de l’enseignant stagiaire et ainsi de mettre en lumière sa capacité à adopter une démarche réflexive quant à sa manière de faire vivre une situation mathématique à ses élèves
Association between physical activity with disease activity and functional disability in patients with inflammatory bowel disease
No full textInternational audienceBackground and aims: The impact of Physical activity (PA) on the activity of inflammatory bowel disease (IBD) remains unclear.Patients and methods: A descriptive cross-sectional study included consecutive patients with Crohn's disease (CD), ulcerative colitis (UC). PA was assessed using the short International Physical Activity Questionnaire. PA was classified as low, medium or high PA. PA was also assessed according to WHO recommendations. IBD activity was evaluated using PRO-2, while IBD-related disability was assessed with the IBD-disk questionnaire.Results: Among a total of 2514 patients (1715 CD), only 28.8% met the WHO recommendations on PA (49.8% had low PA, 35.2% had medium PA, and 15.0% had high PA). Medium and high PA levels were associated with a higher rate of patient-reported clinical remission in patients with CD (OR 1.30 [1.08-1.57] for medium PA, and 1.33 [1.03-1.72] for high PA vs. low PA; p-trend=0.02) but not in those with UC. Higher PA levels were associated with less IBD-related disability in both CD, and UC.Conclusion: In a large cohort of IBD patients, moderate and high PA was associated with higher rates of clinical remission in patients with CD and lower IBD-related disability in both CD and UC patients
Le Journal de l’agriculture, du commerce, des arts et des finances (1765-1783). Histoire et analyse d’une revue économique d’Ancien Régime. Tables complètes et documents. Tome II.
No full textInternational audienceC’est au dix-huitième siècle que se développe en Europe, et plus particulièrement en France, un nouveau type de littérature, l’économie politique. L’essor de cette nouvelle discipline en voie d’autonomisation par rapport aux humanités, au droit ou à la morale, s’est matérialisé par la multiplication des livres consacrés à l’économie, mais aussi par l’apparition de revues spécialisées. Un des plus importants de ces périodiques est le Journal de l’Agriculture, du Commerce et des Finances, mais on ne dispose pas d’études développées sur ce journal – d’autant plus remarquable qu’il dépendait directement du ministère des Finances – et encore moins d’un descriptif. C’est ce qui a motivé les auteurs de cet ouvrage, fédérés autour d’un programme sur la presse économique d’Ancien Régime, à publier ce livre qui a l’originalité de proposer au lecteur dans un même ensemble, composé de deux tomes, une analyse et un descriptif accompagnés de nombreux compléments et annexes construits pour faciliter le travail des chercheurs. Ils trouveront dans cet ouvrage une étude approfondie de l’histoire éditoriale du titre et la table complète de l’ensemble des numéros parus (tome I) puis les professions de foi des éditeurs (avis, avertissements, etc.), l’index (des lieux et des personnes : 4 100 et 6 400 entrées) et les bibliographies des ouvrages cités ou analysés (2 800 références) (tome II)