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Biocide contamination of domestic greywater: an indicator of uses by inhabitants
No full textInternational audienceBiocidal substances are used in several areas of the domestic environment (pharmaceuticals and personal care products, pesticides, cleaning products, etc.) but they can be a threat to environmental and human health. It is therefore essential to characterize contamination by biocidal substances in domestic greywater, which is too poorly documented. This will enable us to estimate the contribution of domestic activities to the biocidal substance discharges into the receiving environment. The aim of this research is (i) to conduct a survey on inhabitant habits in terms of product used and practices; (ii) to characterize domestic greywater contamination by analysing 29 prioritized biocidal substances; and (iii) to compare both approaches in order to assess the effect of inhabitant habits on greywater contamination. To carry out this study, greywater samples were taken from seven dwellings in the Paris conurbation (four washing machine samples, six manual dishwashing samples, five floor cleaning samples, four shower samples and one sink sample). 29 biocidal substances were quantified by liquid chromatography and tandem mass spectrometry. Information about the formulation of products used by participants was collected in order to establish a link between uses and contamination. 3 investigations were conducted in supermarkets to complete information about formulation and improve knowledge on marketed products. 26 molecules were quantified in at least one of the 20 samples. Four substances have a quantification frequency higher than 75%: 3 quaternary ammonium compounds (QACs) and 1 isothiazolinone. The substances quantified vary from one dwelling to another, but much more so according to the type of greywater used. Floor greywaters are the most concentrated when manual dishwashing and shower are the less concentrated. The highest concentrations were measured for QACs (benzalkonium chloride C16 > 20,000 ng/L) in floor greywater. Isothiazolinone and QAC concentrations are highest in greywater in line with the results of the market and inhabitant’s surveys, which highlights the predominance of these molecules. The maximum concentration of cypermethrin measured exceeds 6,000 ng/L and can be explained by the presence of carpeting in corridors outside the dwelling. This new database gives us an idea of biocidal contamination in dwellings. The final aim is to estimate the daily tonnages of biocidal substances emitted from domestic environments via greywater
Amélioration et intégration du transport artisanal à Luanda : processus et résultats de la coopération technique internationale entre la France et l'Angola
No full textInternational audienceDevelopment finance institutions (DFIs) increasingly recognise the importance of informal public transport (IPT) in Sub-Saharan Africa, and are expanding the scope of their urban mobility-focussed technical cooperation and financed projects to include it. Since 2022 Codatu, an NGO based in France, has managed such a technical cooperation programme, funded by AFD, in Angola. The cooperation comprised leveraging Codatu’s international network to respond to knowledge gaps and support local government and operator capacities to plan for improved formal and informal public transport. Activities undertaken in partnership with local stakeholders included regular meetings, expert missions to Angola, and study tours and conference visits in Africa and Europe. This paper reports on the cooperation’s process and outcomes, with a focus on its IPT thematic area. Key findings include that IPT was the mainstay of the urban mobility system, with a nuanced service offer. Government officials and operators recognised this, though national policy advocated relegating IPT to a subsidiary role. The cooperation enabled exposure to IPT improvement processes elsewhere in Sub-Saharan Africa, providing alternative approaches to the replace/displace policy discourse. To realise improved and integrated IPT, government and IPT stakeholders must develop a concrete change management strategy and address persistent capacity constraints.Les institutions de financement du développement (IFD) reconnaissent de plus en plus l'importance du transport artisanal en Afrique subsaharienne et élargissent la portée de leurs projets de coopération technique et de financement axés sur la mobilité urbaine pour l'inclure. Depuis 2022, Codatu, une ONG basée en France, gère un tel programme de coopération technique, financé par l'AFD, en Angola. La coopération a consisté à tirer parti du réseau international de Codatu pour combler les lacunes en matière de connaissances et soutenir les capacités des autorités locales et des opérateurs à planifier l'amélioration des transports publics formels et artisanaux. Les activités entreprises en partenariat avec les parties prenantes locales comprenaient des réunions régulières, des missions d'experts en Angola, des voyages d'étude et des visites de conférences en Afrique et en Europe.Ce document rend compte du processus et des résultats de la coopération, en mettant l'accent sur le domaine thématique du transport artisanal. Les principales conclusions sont que les services artisanaux sont le pilier du système de mobilité urbaine, avec une offre de services nuancée. Les fonctionnaires et les opérateurs l'ont reconnu, bien que la politique nationale préconise de reléguer le transport artisanal à un rôle subsidiaire. La coopération a permis d'exposer les processus d'amélioration du transport artisanal ailleurs en Afrique subsaharienne, fournissant des approches alternatives au discours politique de remplacement/déplacement. Pour améliorer et intégrer le transport artisanal, le gouvernement et les opérateurs concernés doivent élaborer une stratégie concrète de gestion du changement et s'attaquer aux problèmes de capacité persistants
Wealth, Portfolios, and Unemployment Duration
No full textInternational audienceWe use administrative data on individual balance sheets in Denmark to document how an individual's financial position affects job search behavior. We look at the effect of wealth at the entry into unemployment on the exit rate from unemployment as well as the effect on the subsequent match quality. The detailed data allows us not only to distinguish between liquid and illiquid parts, but also to decompose each of them into assets and liabilities. The decomposition of wealth into these four components is key to understanding how wealth affects job finding rates. In particular, we show that liquid assets reduce the probability of becoming re-employed, but we do not see an effect of liquid liabilities or the illiquid wealth components, while interest payments speed up re-employment. The results on subsequent match quality in form of job duration and wages are mixed
Fournir un travail de care dans le guichet : le cas des agent·es de proximité RATP dans la prise en charge des victimes de violences sexuelles sur le réseau ferré
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Hard infrastructuring of rivers vs. Nature-based solutions: dynamic status-quo?
No full textInternational audienceThe hard infrastructuring of rivers has often been considered essential to accompany human development and remains today a way of thinking about the link to rivers in order to minimise the impacts of global changes. This choice is deeply embedded in the engineering society, but different trends prompt stakeholders to adapt their visions and to become softer. This last decades, the principles of ecological river management have been adopted with a removal of some infrastructures and processes of ecological restoration. New ways of thinking the relationships to the rivers have been emerging through hybrid solutions combining of grey and green infrastructures to integrate considerations of biodiversity conservation, climate change adaptation. Actually, environmental constraints and narratives urge the professional culture of the hegemonic civil engineering to adapt their practices and to integrate other ways to work with the rivers. That is why it appears interesting to question, that the promises of infrastructure can be renewed with climate change concerns and to study the ongoing process of "dynamic status quo" between a dominant infrastructuring movement and those promoting nature-based solutions. As the agentivity of non-humans is constantly reminded through extreme events and dysfunctions of the human artefacts, “the classic hydraulic tradition” is obliged to evolve and, in the same time, criticised and challenged by the emerging “Nature based solutions” epistemic community, more and more supported by local and national authorities (funding, regulatory norms, etc.). We will illustrate our reflection though the discussion of two case studies dealing with two rivers (Seine and Rhine)
Incertitudes, modalités d'actions et objets/organisations frontières : à la recherche d'une littéracie commune ? (Exemple de la filière forêt-bois)
No full textInternational audienceLes politiques climatiques s’organisent généralement autour d’une expertise climatique qui décline les vulnérabilités sociétales des territoires en fonction des grands aléas climatiques répertoriés et leurs risques associés pour les populations, leurs activités et les territoires. Cette première catégorie de risques s’organise autour de la sensibilité des populations et activités à différents aléas, en tenant compte des effets cascade à différentes échelles territoriales en fonction des flux de matières et des interdépendances en termes d’activités et d’acteurs concernés. Ces raisonnements relèvent de l’analyse systémique ainsi qu’en témoigne une des définitions parmi d’autres de la résilience territoriale au changement climatique. Cette dernière rend compte de la complexité des équations à laquelle l’élaboration de stratégies de résilience sont confrontées. Entre risques en cascade, boucles de rétroactions, logiques propres organisationnelles dans les prises de décision ou encore jeux des acteurs (rotation des équipes, cultures générationnelles, etc.), les équilibres systémiques sont par définition sinon instables en tout cas soumis à variation en fonction de nouveaux aléas physiques, géopolitiques et des paramétrages issus de système de décision, eux-mêmes sujets à fluctuations en fonction des jeux d’acteurs dans leurs organisations, au sein d’arènes hybrides, de modalités de gouvernance, etc. De manière générale, un tel contexte peut servir tant les protagonistes de l’action que de l’inaction climatique. Pour paraphraser Niklas Luhmann (Luhmann, 1992), l’éviction d’un risque engendre d’autres risques. Cette formulation ne rend certes pas hommage à la richesse de la pensée de son auteur, il n’en demeure que c’est souvent sous cette forme communicationnelle que les plus grandes théories et modèles scientifiques diffusent dans la société. Ces slogans irriguent la pensée sociale dans différents contextes et circonstances et peuvent alimenter des intérêts opposés. L’instrumentalisation de ces derniers est d’usage. Comment parer une telle destinée ? Se ressaisir de la richesse du propos au profit d’une action mesurée, réflexive et précautionneuse ? C’est là l’objet de notre propos autour du coût de l’action et de l’inaction en régime de changement climatique (Rudolf, 2018). Nous abordons cet enjeu à partir d’une décennie de recherche-action transfrontalière menée dans le cadre d’un programme ANR (SECIF, 2011-2014) et des programmes INTERREG V et VI (Clim’Ability ; Clim’Ability Design ; Clim’Ability Care, 2016-2026)
Upscaling materials recycling to enhance sustainability and economic resilience
No full textInternational audienc
Des instantanés pour une histoire du changement (Introduction)
No full textInternational audienceComment capter la dynamique du temps qui travaille l’espace ? Comment saisir ce qui est en mouvement, multiforme, immense ? Ce texte introduit l'ouvrage collectif "Photographier le Grand Paris" qui pose comme hypothèse que l’on ne peut comprendre l’histoire du Grand Paris – sociale, architecturale, urbaine, paysagère, politique – et son aménagement, sans comprendre les images que cette histoire a produites, et les finalités diverses selon lesquelles elles ont été créées, interprétées, médiatisées, conservées. Autrement dit, l’histoire visuelle du Grand Paris est une dimension indissociable de son changement, dont la photographie est un marqueur. Cette dernière permet de documenter les transformations, qu’elles soient matérielles, institutionnelles, sociales, environnementales. C’est l’enjeu scientifique et conceptuel de cet ouvrage que ce texte introduit : écrire une histoire de la photographie du changement métropolitain tout en questionnant la figurabilité d’une métropole en perpétuelle évolution
Advancing Cybersecurity in Healthcare: Challenges and Solutions
No full textThe healthcare sector has increasingly embraced electronic health records (EHR), medical technologies, and the Internet of Things (IoT) to enhance the efficiency and quality of healthcare services. This has given rise to the Internet of Medical/Health Things (IoMT/IoHT) and the adoption of telemedicine and remote healthcare services, particularly in response to the COVID-19 pandemic. While these advancements provide convenient solutions for remote healthcare delivery, they also introduce new cybersecurity considerations and vulnerabilities for healthcare institutions, making cybersecurity a critical concern. Malicious actors target healthcare networks due to the valuable data they contain and the inadequate cybersecurity defenses in place, compromising patient data confidentiality, integrity, and availability, disrupting medical services, and jeopardizing patient safety. Robust cybersecurity measures and frameworks are essential to prevent cyber attacks in healthcare systems.Despite efforts to address these challenges, significant obstacles persist in areas such as big data analytics, exploration of blockchain technology, standardization, and regulatory compliance. Healthcare organizations must prioritize educating and training their staff in cybersecurity best practices, fostering cyber-aware environments, and ensuring the confidentiality and trustworthiness of healthcare solutions. Implementing risk management strategies to assess the safety and security of medical devices and systems is crucial. Proposed approaches aim to improve cybersecurity and mitigate the risks of intelligent and advanced cyber attacks. However, further research and development are needed to enhance healthcare system cybersecurity and safeguard patient data privacy and safety. Compliance with regulatory requirements and frameworks for healthcare cybersecurity, as well as certification schemes, are essential, as well as education and training of staff in cybersecurity best practices.This Research Topic focuses on recent advancements in critical cybersecurity measures, including but not limited to technologies such as artificial intelligence (AI), machine learning (ML), and blockchain technology. The objective is to explore how these technologies can be applied in proposed architectures and infrastructures to address data validation, ensure the authenticity of data and receivers, detect attacks, and secure AI algorithms and applications. It also emphasizes the need for authentication and access control at a large scale and examines the potential impact of GenerativeAI on efficiency, security, and the implementation of mitigation measures. This Research Topic also explores the utilization of next-generation firewalls to detect and block advanced persistent threats (APTs), vulnerability assessment tools and procedures to identify and mitigate security weaknesses, and the implementation of digital twins for simulating and testing the effectiveness of cybersecurity measures. Healthcare frameworks should prioritize device certification against standardized vulnerabilities and authenticate healthcare services to prevent unauthorized access to sensitive data. The emergence of EHR standards and distribution formats such as the Fast Healthcare Interoperability Resources (FHIR) adds a critical perspective to this research, given its current momentum and implications on future security strategies. Considering the substantial volume and accessibility of data within the healthcare sector, establishing secure and scalable mechanisms for data sharing is of utmost importance, warranting comprehensive investigation and analysis in this Research Topic.This Research Topic aims to compile and examine the current state of the art in emerging cybersecurity solutions, focusing on their developments, issues, and challenges. We invite original, unpublished, and novel research submissions that provide in-depth exploration and contribute significantly to the field in terms of methodology or application. We welcome a range of article types, including reviews, case studies, commentaries, theoretical works, and perspectives
Caméra
No full textInternational audience"Se placer en quête de formes d’expression qui transcendent nos représentations individuelles, en mobilisant les outils à la portée de toutes et tous, s’impose pour esquisser des lieux communs souhaitables."Cet article propose une réflexion critique sur le rôle de la caméra pour penser, étudier, concevoir la ville. Il est illustré par Djohr. Cette contribution prend place dans un ouvrage coordonné par Loïc Vadelorge et issu d'un travail de quinze années de recherche du laboratoire d’excellence Futurs Urbains. Le LabEx étudie les dimensions sociales, environnementales, matérielles et infrastructurelles du changement urbain