ED Droit
The group of companies in labour law : A comparative study of French and Vietnamese Law
by Tuan Kiet NGUYEN (COMPTRASEC - Centre de Droit Comparé de Travail et de la Sécurité Sociale)
The defense will take place at 14h00 - Salle des thèses de la Faculté de droit de l'Université de Bordeaux Salle des thèses de la Faculté de droit de l'Université de Bordeaux Bâtiment C, Travée C1 16 avenue Léon Duguit 33608 Pessac Cedex
in front of the jury composed of
- GILLES AUZERO - Professeur - Université de Bordeaux - Directeur de these
- Jean-Christophe PAGNUCCO - Professeur - Université de Caen - Rapporteur
- Lucas BENTO DE CARVALHO - Professeur - Université de Montpellier - Rapporteur
- Sébastien TOURNAUX - Professeur - Université de Bordeaux - Examinateur
- Ngoc Dien NGUYEN - Professeur - Université d'Économie et de Droit, université membre de l'Université nationale du Vietnam – Ho Chi Minh-Ville - Examinateur
Labour relations within corporate groups are inherently complex: economically, the group operates as a unified entity, whereas legally, it lacks legal personality and is composed of multiple independent legal entities. This structural dissociation allows the parent company to exploit the corporate form in ways that may undermine workers' rights. In a comparative perspective, Vietnamese law remains underdeveloped in this area, while French law has elaborated a variety of protective mechanisms. However, individual protection is no longer sufficient; in the face of profound upheavals brought about by the green and digital transitions, collective protection for workers becomes essential. In this context, the group-level collective agreement emerges as a key instrument of a just transition, insofar as it ensures both coherent corporate governance and safeguards against the marginalisation of workers. It thus reflects a contemporary legislative philosophy aimed at promoting responsible business conduct and grounded in the pursuit of a balance between the protection of the individual and economic adaptability.
ED Sciences et environnements
Variability of the Northwesterlies across the Mid-Pleistocene Transition (~1.2–0.65 million years ago), a Crucial Transition Leading to a Progressive Increase in Global Ice Volume
by Xiaowen QUAN (Environnements et Paléoenvironnements Océaniques et Continentaux)
The defense will take place at 14h00 - Univers (salles 021 et 022) Bâtiment B18N, Laboratoire EPOC, Allée Geoffroy Saint Hilaire, 33615 Pessac Cedex
in front of the jury composed of
- Qiuzhen YIN - Professeure - Catholic University of Louvain - Examinateur
- Amaelle LANDAIS - Directrice de recherche - CNRS, LSCE - Univ. Paris-Saclay - Examinateur
- Youbin SUN - Full professor - University of Chinese Academy of Sciences - Rapporteur
- Timme H. DONDERS - Associate Professor - Utrecht University - Rapporteur
- Stephen BARKER - Full professor - Cardiff University - Rapporteur
- Maria SANCHEZ GONI - Professeure - Université de Bordeaux - Directeur de these
The Mid-Pleistocene Transition (MPT, ~1200-650 ka) marks a major reorganization of the Quaternary climate system, characterized by a shift from dominant 41 kyr to ~100 kyr glacial cycles, without significant changes in orbital periodicity. The mechanism behind this transition remains debated, particularly the roles of insolation forcing, ice-sheet dynamics, and atmospheric circulation. This study explores the variability of the North Atlantic westerlies at both orbital and millennial timescales across the MPT using a composite high-resolution deep-sea pollen record from the southwestern Iberian margin, with the aim of better understanding the processes leading to the emergence of 100 kyr ice age cycles. At orbital-scales, the pollen record reveals a three-phase evolution in the vegetation, linked to changes in boreal summer insolation amplitude and ice-sheet boundary conditions. During the early phase (~1200-930 ka, Marine Isotope Stage (MIS) 35-25), relatively strong Mediterranean forest development reflects the arrival of precipitation in Iberia consistent with large precession-driven insolation amplitudes that drove the westerly northward during insolation minima, enhancing the moisture transport to higher latitude. This favored ice accumulation that partially melted during insolation maxima promoting limited ice growth. The middle phase (~930-790 ka, MIS 24-20) was characterized by a significant contraction of the Mediterranean forest contemporaneous with reduced precession-driven insolation amplitude, which lowered temperature, and displaced the westerlies toward the south limiting the arrival of precipitation to Iberia. Together with regolith erosion, this sustained temperature-driven ice-sheet expansion triggered the mega-droughts during glacials MIS 24, 22, and 20 leading to a significant expansion of semi-desert vegetation. In the late phase (790-668 ka, MIS 19-17), Mediterranean forest expanded in parallel with the increasing insolation amplitude that intensified the northward shift of the westerlies, and enhanced moisture transport to mid–high latitudes. This progressive northward shift of the westerlies likely promoted the forest expansion, and likely the development of 100 kyr glacial cycles. At millennial timescales, the record documents persistent Millennial Climate Variability (MCV) across the MPT, with both frequency and amplitude varying between phases. Comparison with the hemispheric (global) MCV stack shows that the Mediterranean Forest pollen (MFp) record contains fewer events but exhibits larger amplitude fluctuations, suggesting influences from regional processes, proxy sensitivity, and ecological buffering. The amplitude of MCV shows a clear phase-dependent pattern. During the early phase, MIS 35-25, large-amplitude is closely linked to eccentricity-modulated precessional forcing, which enhances seasonal contrasts and vegetation sensitivity to winter precipitation. During the middle phase, MIS 24–20, strongly reduced amplitudes were associated with expanded ice sheets and increased IRD discharge, which likely drove a southward shift of the westerlies and dampened hydroclimatic variability, reflecting a shift to ice-sheet control on MCV. Increased amplitudes are recorded again during the late phase, MIS 19–17, under enhancing orbital forcing, with MIS 18 showing an exceptionally large amplitude event likely related to intermediate ice-sheet conditions and nonlinear interactions between orbital and millennial scale variability. Overall, these results indicate that insolation amplitude modulates the position of the North Atlantic westerlies at orbital timescales, while MCV in the westerlies evolves from orbital-dominated variability to ice-sheet stabilization, and finally to a coupled nonlinear regime. These processes together contribute to ice-volume changes and the progressive emergence of 100 kyr glacial cycles across the MPT.
ED Sociétés, Politique, Santé Publique
Cognitive training by neurofeedback-EEG for athletes' performance: an interdisciplinary user-centred approach
by Margaux IZAC (Bordeaux Population Health Research Center)
The defense will take place at 15h00 - Amphi BBS, Bâtiment Bordeaux Biologie Santé, 2 Rue Dr Hoffmann Martinot, 33000 Bordeaux
in front of the jury composed of
- Bernard N'KAOUA - Professeur des universités - Université de Bordeaux - Directeur de these
- David AMARANTINI - Professeur des universités - Université Toulouse III Paul Sabatier - Rapporteur
- Raphaëlle N. ROY - Professeure des universités - ISAE-SUPAERO - Rapporteur
- Franck DI RIENZO - Maître de conférences - Université Claude Bernard Lyon 1 - Examinateur
- Aymeric GUILLOT - Professeur des universités - Université Claude Bernard Lyon 1 - Examinateur
- Camille JEUNET-KELWAY - Chargée de recherche - CNRS - CoDirecteur de these
Motor imagery (MI), defined as the mental representation of an action without physical execution, is a central component of high-level athletic training. Numerous findings demonstrate its effectiveness in enhancing attentional, affective, and motor components of performance. However, unlike physical execution, MI is not accompanied by directly perceptible sensory or proprioceptive feedback. This lack of objective feedback limits athletes' ability to evaluate the effectiveness of their mental strategies and to monitor their progress over time. Electroencephalographic neurofeedback (NF) enables the recording and restitution of neurophysiological markers associated with MI. Thus, NF helps overcome one of the main limitations of MI by providing athletes with real-time information about the regulation of their brain activity. Despite encouraging results in sport contexts, NF remains scarcely integrated into training routines. The heterogeneity of NF protocols and the inter- and intra-individual variability of their effects complicate data interpretation and prevent robust conclusions regarding its effectiveness. The main objective of this thesis is to identify NF parameters associated with optimal performance gains and to examine how individual athlete characteristics (personality traits, gender, age, expertise, and sport practice) may guide their selection. We hypothesise that the relevance of targeted neurophysiological markers, as well as feedback content, instructions, and session duration, should be adapted to athletes' profiles, particularly their level of sport expertise. This work was structured around three complementary objectives: 1) To identify the most frequently employed NF parameters and those associated with performance improvements in the sport literature. 2) To examine how individual athlete profiles influence MI practices, interest in NF, and preferences regarding its design. 3) To determine whether MI induces distinct neurophysiological modulations in novices and experts, in order to better guide the selection of neurophysiological markers in NF interventions aimed at enhancing sport performance. By proposing an integrative, user-centred approach, this thesis contributes to clarifying the mechanisms underlying NF-related performance gains and to formulating recommendations for personalised protocols tailored to athletes' profiles and needs.