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Figuring out Non-Academic Research Impact With(out) FiguresA European Exploratory Study
No full textInternational audienceWhile a growing number of research in management and organization studies interrogates the influence of the impact agenda on universities’ organization and management, in particular in the United Kingdom and Australia – two countries that developed impact assessment frameworks -, empirical investigations of how researchers themselves define and evidence the non-academic impact of their works are scarce. In particular, the influence of the evidence-based approach and the primacy given to quantification both in this approach and in public administration institutions on the way researchers conceive evidence of non-academic impact remain to be scrutinized. Relying on 22 case-studies based on in-depth interviews conducted with researchers in management and organization studies in a broad sense from Great Britain, France, Italy, Germany and Poland, our research reveals three understandings of non-academic impact that sharpen current definitions of non-academic impact: as solving practical, real-life problems; as giving people means to develop through feedbacks or reports; and/or as changing or inspiring people’s thoughts on important issues. The analysis also shows that researchers establish diverse relationships between their definition and evidence of non-academic impact: from a muscular relationship in which both non-academic impact and evidence are defined through numbers, to looser relationships where definition - that may be defined with qualitative underpinnings, and evidence that may be quantitative -, are either disconnected from one-another, or loosely coupled when impact is hypothesized and evidence defined as indirect signs of interests from potential audience. These diverse relationships between definition and evidence of impact are interpreted as tensions between research ethos – in which accounting rigorously for a process or a cause-and-effect relationship is of primary importance – and the impact agenda and concomitant influence of evidence-based management approach – which tend to give more value to evidence that can be expressed in numbers
Structural transitions related to order-disorder and thermal desorption of D atoms in TbFe2D4.2
No full textInternational audienceTbFe₂D4.2 deuteride crystallizes in a monoclinic structure (Pc space group) with deuterium inserted into 13 [Tb2Fe2] and 5 [TbFe3] tetrahedral interstitial sites. Its structural evolution versus temperature has been investigated by combining in-situ X-ray and neutron diffraction (XRD and NPD) with differential scanning calorimetry (DSC) experiments. Upon heating, the deuteride undergoes a reversible order-disorder transition from an ordered monoclinic structure to a disordered cubic structure between 320 and 380 K. Then, a multipeak thermal desorption occurs between 400 and 550 K, which can be explained by the transitions between different cubic deuterides separated by two-phase ranges. After controlled partial D desorption of TbFe₂D4.2, the XRD patterns of several TbFe2Dx deuterides were measured ex-situ using synchrotron radiation at room temperature, revealing the formation of different phases with cubic (x < 3 and x ≥ 4.5) or monoclinic structures (3.6< x< 3.8, x = 4.2(1)) separated by two-phase ranges. A tetragonal superstructure was observed for a phase with x ≈ 2 and the corresponding atomic positions of the metal atoms are reported. This work can explain previous results of the literature indicating the existence of cubic and/or rhombohedral hydrides depending on the hydrogenation conditions and the H or D content. The monoclinic structures reported here correspond to a slight distortion of the previous rhombohedral structures described by other authors
Qualitative Trends versus Quantitative Accuracy: A Case Study of LiMn<sub>1.5</sub>Ni<sub>0.5</sub>O<sub>4</sub> Cathode Material
No full textInternational audienceLiMn1.5Ni0.5O4 is a high-voltage cathode material for Li-ion batteries. The effects of Ni/Mn ordering and nickel content on its electrochemical behavior remain ambiguous. DFT can provide essential insights into these phenomena. We benchmark four exchange-correlation functionals (PBE, PBE+U, r2SCAN, and HSE06) for LixMn1.5Ni0.5O4 (x = 1, 0.5, 0) against experimental data. We evaluate key properties: operating voltage, voltage differences between Ni3+/Ni2+ and Ni4+/Ni3+ redox couples, magnetic and crystallographic structures, structural response upon delithiation, and oxygen K-edge EELS spectra. PBE underestimates the average voltage (3.94 V vs. 3.73 V) and overestimates redox voltage differences (114 mV vs. 15 mV), but captures essential trends in structural and electronic properties at moderate computational cost. While PBE+U improves voltage accuracy, it predicts an unstable half-lithiated phase and incorrect magnetic configurations. r2SCAN yields mixed results. HSE06 provides the highest accuracy for some results but at significant computational expense. PBE emerges as the best compromise for modeling LixMn1.5Ni0.5O4 phases
Quand « être soi » devient la norme: Trajectoires de changementcomportemental managérial par les normes sociales (modèle D/AD/IP/AN)
No full textInternational audienceLes normes sociales constituent un levier majeur des politiques de changement comportemental. Dans les organisations, elles ne se limitent pas à orienter des conduites observables : elles travaillent les identités professionnelles et déplacent la conformité vers un « bon style de soi ». Nous posons la question suivante : comment des dispositifs organisationnels mobilisant des normes descriptives et injonctives transforment-ils un changement comportemental managérial en trajectoire d’ajustement identitaire, jusqu’à une « authenticité prescrite » ? À partir d’une enquête qualitative multi-cas (5 organisations françaises ; 22 entretiens) complétée par une autoethnographie, nous proposons un modèle processuel en quatre moments idéal-typiques (D/AD/IP/AN). Les résultats montrent le passage d’une domestication contrainte à l’autodomestication, puis à un isomorphisme personnel, jusqu’à une authenticité normée où « être soi » devient un script évalué. Nous identifions six mécanismes organisationnels qui combinentattentes empiriques (observation des pairs) et attentes normatives (ce qui est jugé attendu) etdiscutons les effets indésirables (boomerang, exclusion, sorties) et les enjeux éthiques d’unegouvernance des conduites fondée sur les normes
From German Mines to Le Nôtre's Gardens: The Origin of the Lead in the Fountains of Vaux‐le‐Vicomte and Versailles (Île‐de‐France, France)
No full textInternational audienceThis article presents the results of an isotopic study of the lead used in the fountains of the gardens at the palaces of Versailles and Vaux‐le‐Vicomte—two iconic examples of French formal gardens designed by André Le Nôtre. The construction of these monumental gardens in the 17th century required considerable quantities of lead, a material not found in the subsoil of the Paris region and therefore necessarily imported. Lead Isotope analysis of 16 samples (including pipes, solder joints and basin plates) reveals a homogeneous signature, indicating a shared supply source for both sites. Comparing these results with those from different European mining districts revealed a clear correspondence with the deposits in the Harz Mountains in Germany, which were active and important in the 17th century. However, a few samples associated with later construction phases suggest that additional supplies came from other deposits, probably located in France. These results highlight not only the importance of European trade networks in the supply of construction materials but also the geopolitical dimension of these choices, as Louis XIV's France sought to produce lead in order to substitute it for that obtained through costly imports
Antibiotic Use and the Persistence of Biologic Therapies in Patients With Psoriasis
No full textInternational audienceImportance The long-term effectiveness of biologic therapies in psoriasis may decline over time. Gut microbiota alterations induced by antibiotics have been proposed as a potential mechanism impairing biologic persistence. Objective To evaluate the association between antibiotic exposure and the persistence of biologic therapies in patients with psoriasis. Design, Setting, and Participants This retrospective cohort study used data from the French National Health Insurance database between June 2011 and December 2022. Adults initiating a biologic therapy for psoriasis were included, excluding those with preexisting inflammatory bowel disease at baseline. Data were analyzed from January to September 2024. Exposures At baseline, antibiotics exposure was classified as none, 1, or 2 or more dispensations in the 6 months preceding the index date. During follow-up, time-dependent antibiotics exposure was defined as none, 1, or 2 or more antibiotics dispensations in the 6 months prior to each time of follow-up. Main Outcomes and Measures The primary outcome was discontinuation or switch of the initial biologic therapy. Exposure to antibiotics was assessed within 6 months prior to biologic initiation and during follow-up. A weighted Cox marginal structural model was used to estimate adjusted hazard ratios. Results Of 36 129 included patients, 11 228 (42.0%) were female, 20 192 (55.9%) were male, and the mean (SD) age was 48.4 (15.1) years. A total of 9366 (25.9%) were exposed to antibiotics at baseline and 21 900 (60.6%) during follow-up. The most commonly prescribed antibiotic classes were β-lactams, macrolides, and fluoroquinolones. Antibiotic exposure was associated with a higher risk of biologic discontinuation (weighted hazard ratio, 1.12; 95% CI, 1.08-1.16), with a stronger effect observed for multiple dispensations (weighted hazard ratio, 1.29; 95% CI, 1.24-1.35), suggesting a dose-response relationship. Conclusions and Relevance In this cohort study, antibiotic exposure was significantly associated with an increased risk of discontinuation of biologic therapies in psoriasis. These findings support the hypothesis that antibiotics, potentially through gut dysbiosis, may reduce biologic persistence. However, unmeasured confounders limit causal interpretation. Further studies are necessary to validate these findings
Causality and communication in physics
No full textUnderstanding the concept of causality is fundamental in physics, as it conditions the very possibility of any exchange of information between physical systems. This article examines and compares three main interpretations of the correlative operational concept of "causal separation" that have been respectively proposed in special relativity, quantum theory, and according to the statistical "non-signalling" condition. These interpretations, which can be classified regarding the range of CHSH correlation degrees they allow, lead to radically different results regarding the exchange of information between physical systems. Namely, it can be shown that, in opposition with the non-communication theorem of quantum theory, non-local communication can be established between the two entangled parts of a physical system when the relativistic criterium of causal separation is satisfied but not the quantum one
Notes sur l'opérateur de trace omnidirectionnel
No full textThese are notes on an article by R. Eymard, T. Gallouët, D. Maltese and Y. Vincent about the omnidirectional trace operator, written to better understand the issues and the objects
Thirty years of nitrogen dynamics in European agri-food systems: a territorial metabolic perspective
No full textInternational audienceEuropean agri-food systems face the dual challenge of reducing their environmental footprint, particularly nitrogen losses, while meeting the demands for both food and non-food biomass. Because future responses will have to build on the legacy of past trajectories, addressing this challenge requires a sound, fine-grained understanding of those trajectories. In the present study, we address this challenge by compiling a dataset (1990–2019) quantifying nitrogen flows across the agri-food systems of 120 European territories. Using this dataset, we apply the generalized representation of agri-food systems framework to classify agri-food systems into six types representing different degrees of specialization. Our results show that agricultural systems became increasingly specialized, rising from 22% of specialized territories in 1990 to 36% in 2019, indicating a growing reliance on external feed and fertilizer inputs. Most of these transitions occurred in eastern Europe, predominantly toward stockless cropping systems. Although these evolutions unfolded within broader processes of market liberalization, transition patterns also displayed clear path-dependency effects rooted in the material configuration of agri-food systems. This is evidenced by the analysis of transition frequencies, which shows that some transitions occurred repeatedly while others never occurred, pointing to the influence of initial system configurations on subsequent trajectories. By contrast, changes in agro-environmental performance were only weakly linked to system transitions. The increases in nitrogen use efficiency (from 0.57 to 0.70) and declines in nitrogen surplus (from 68 to 49 kg N ha −1 ) rather coincided with higher yields and increased nitrogen input application rates, pointing to the dominant role of factors not explicitly captured here, such as shifts in agronomic practices and pedo-climatic conditions. Taken together, these findings provide both a critical dataset and a robust understanding of recent territorial agri-food trajectories, thereby offering a solid empirical basis for anticipating future transitions and developing scenario-based analyses
A statistical approach to unveil phytoplankton adaptation to ocean fronts
No full textInternational audienceAbstract. Fine-scale oceanic fronts are ubiquitous and ephemeral physical features that separate contrasting water masses, creating significant heterogeneity in the physical seascape and plankton distributions. Because phytoplankton community composition (PCC) is a key driver of marine ecosystem functioning, understanding the extent to which fine-scale fronts influence PCC is a critical challenge. However, studying PCC across and within fronts is particularly difficult due to data scarcity and high biophysical variability. We developed a tailored statistical model to characterize PCC within an oceanic front we studied in the Mediterranean Sea. We modeled the frontal community as a finite mixture model with three components: two communities of adjacent water masses and a potential front-adapted community. Each component was further considered as a discrete mixture of an unknown number of multivariate Gaussian sub-components. First, we used an Expectation–Maximization algorithm to estimate the Gaussian parameters and determine the optimal number of sub-components based on in situ datasets of the PCC within a frontal zone and its adjacent water masses. Second, a hierarchical Bayesian approach was applied to estimate the weight of all components within the frontal dataset. Our analysis suggests that within the front a new community component, distinct from those in adjacent water masses, accounts for 70 % of the frontal community, indicating that a specific phytoplankton community can emerge in fine-scale oceanic fronts. Despite the limited number of frontal observations, our Bayesian modelling approach provides statistical evidence of the front's influence on phytoplankton community composition, effectively overcoming data scarcity and high variability