ED Entreprise Economie Société
From Financial Accounting to Sustainability: A Data-Driven Hybrid Life Cycle Assessment Framework for Decarbonization and Decision-Making in Corporate Procurement
by Widiene ESSOUID (IRGO - Institut de Recherche en Gestion des Organisations)
The defense will take place at 13h00 - A communiquer Pôle universitaire de sciences de gestion IRGO - Bat C 4° étage UFR 405 - 35, avenue Abadie 33072 BORDEAUX CEDEX
in front of the jury composed of
- Stéphane TREBUCQ - Professeur des universités - Université de Bordeaux - Directeur de these
- Steven YOUNG - Professeur des universités - Université de Waterloo - Rapporteur
- Guido SONNEMANN - Professeur des universités - Université de Bordeaux - CoDirecteur de these
- Andrea THORENZ - Maîtresse de conférences - Université d'Augsbourg - Examinateur
- Gérald NARO - Professeur des universités - Université de Montpellier - Rapporteur
- Eric SEVERIN - Professeur des universités - Université de Lille - Examinateur
- Christian PRAT DIT HAURET - Professeur des universités - Université de Bordeaux - Examinateur
In response to growing environmental and social imperatives, companies are increasingly encouraged to address sustainability impacts across their value chains. Scope 3 emissions accounted for accounting to the GHG Protocol, particularly those related to procurement, represent a large share of corporate carbon footprints but remain the most complex to assess. This dissertation explores the systemic, methodological, and organizational challenges of Scope 3 procurement-related carbon accounting and proposes a hybrid, semi-automated framework to improve precision, coverage, and relevance. The first contribution is a critical review of existing carbon accounting methods. While process-based Life Cycle Assessment (LCA) provides detailed product-level data, and Environmentally Extended Input-Output (EEIO) models offer broad economy-wide coverage, both approaches face structural limitations when used in isolation. Drawing on Life Cycle Sustainability Assessment (LCSA), this work develops an integrated approach combining environmental indicators such as carbon and water footprints, economic parameters, and social metrics including gender wage gaps and fair salary, expanding sustainability assessment beyond carbon. This multidimensional approach aligns with emerging sustainability reporting standards and academic frameworks. The second contribution is a systemic diagnosis of reliability challenges in Scope 3 accounting. Using a mixed-method design, including a systematic literature review, expert survey, and MICMAC structural analysis (Matrice d'Impacts Croisés Multiplication Appliquée à un Classement), this research identifies interdependent challenges and classifies them within the 6M framework: Man, Method, Material, Machine, Measurement, and Management. These insights inform a strategic roadmap based on the Sustainability Balanced Scorecard (SBSC), providing actionable recommendations to embed data quality and sustainability performance into procurement governance. The third and main contribution is the development of a Systematic Tiered Hybrid LCA model, tailored to industrial and service sectors in France. This model integrates EEIO data, process-based LCA data, and supplier-specific disclosures. A rule-based, semi-automated algorithm dynamically selects the most robust available data, monetary or physical, depending on procurement line-item characteristics. The model operates at the sector level using financial data and EEIO coefficients, or at the product level using physical quantities and process-specific emission factors. This ensures both scalability and accuracy. The flexible architecture reduces data gaps, improves resolution, and ensures alignment with regulatory and organizational requirements. The model was validated with Eiffage, a major player in the French construction sector, confirming its practical feasibility and relevance for corporate decarbonization strategies. Theoretically, the dissertation advances hybrid sustainability accounting and operationalizes LCSA in procurement contexts. Practically, it proposes a scalable, reproducible framework to help companies comply with evolving regulations and integrate environmental and social responsibility into procurement decisions. By combining life cycle thinking, digital automation, and multidimensional indicators, this work promotes a systemic, accountable approach to sustainable governance. More broadly, it supports data-driven innovation and the transformation of procurement from a cost-centered role into a strategic driver of corporate sustainability and resilience on the way to a carbon-neutral society.
ED Sciences de la Vie et de la Santé
Hippocampal cognitive impairment and n-6/n-3 polyunsaturated fatty acids balance modification in adult: sex heterogeneity
by Ivan MARNIQUET (Nutrition et Neurobiologie Intégrée)
The defense will take place at 14h30 - Amphitéatre Centre 146 rue Léo-Saignat, Centre Broca Nouvelle-Aquitaine, 33076, Bordeaux
in front of the jury composed of
- Jean-Christophe DELPECH - Chargé de recherche - Université de Bordeaux - Directeur de these
- Sandrine THURET - Professeure - King's College London - Rapporteur
- Mario CARTA - Chargé de recherche - Université de Bordeaux - Examinateur
- Mélanie PLOURDE - Professeure des universités - Université de Sherbrooke - Rapporteur
- Bruno BONTEMPI - Directeur de recherche - Université de Bordeaux - Examinateur
- Géraldine POISNEL - Ingénieure de recherche - Université de Caen - Examinateur
Cognitive impairment, particularly hippocampal dependent memory deficit, is due in part to environmental factors such as nutrition. Indeed, throughout life, nutrition plays a part in establishing and maintaining an optimal cognitive reserve, defined as our brain's ability to respond efficiently to any cognitive demand in order to limit cognitive decline. Nutrition, and more specifically the balance of n-6/n-3 polyunsaturated fatty acids (n-6/n-3 PUFAs), has been extensively studied in relation to cognitive impairment throughout life. Clinically, links have been shown between accelerated cognitive decline and reduced n-3 PUFA consumption, as well as between n-3 PUFA supplementation and beneficial effects on memory in elderly subjects. Preclinical studies have also demonstrated that n-3 PUFA deficiency from gestation disrupts spatial memory, and induced alterations in hippocampal neuronal functions and in the brain's resident immune cells, the microglia. Nevertheless, many questions remain unanswered, including a better understanding of the heterogeneity of forms of decline in relation to PUFA intake, and the underlying mechanisms as a function of sex, given that most preclinical work has been carried out in males only. In this context, the aim on my thesis was initially to evaluate in adulthood cognitive impairment of spatial memory induced by gestational n-3 PUFA deficiency, in both sexes. My hypothesis was that n-3 PUFA deficiency would also induce an alteration in contextual memory, a form of episodic memory, associated with an alteration in neuronal functions of the CA1 of the dorsal hippocampus involved in those memory function. Finally, given that spatial and episodic memory are particularly sensible to age-related cognitive decline, we hypothesized that a good n-6/n-3 PUFA balance could prevent the deficits observed in a mouse model of accelerated aging. My results show that a gestational deficiency in n-3 PUFA leads to a deficit in spatial and contextual memory in adult males and females, based on the alteration of different parameters according to sex. This heterogeneity is particularly evident in contextual memory performance, with females showing a memory deficit as early as 24 hours after learning, whereas it appears 10 days later in males. At the cellular level, these memory deficits are associated with increased intrinsic excitability of pyramidal CA1 neurons of the dorsal hippocampus in females; and an absence of long-term potentiation, considered to be the substrate of memory, in males. At the protein level, altered activity of protein kinases and synaptic proteins was demonstrated with sex-specific modulation. In regards to our study on the protective effects of a balanced PUFA diet on cognitive aging, my results indicate that a balanced n-6/n-3 PUFA ratio protects contextual memory associated with a correction of neuroinflammation in the hippocampus. Overall, these results provide some insight into the mechanisms involved in the optimal functioning of the hippocampus and normal cognitive capacity. These results help to improve our understanding of the importance of a good n-6/n-3 PUFAs intake for the establishment of an optimal cognitive reserve while highlighting the necessity to take sex heterogeneity into account.