Université de Toulon

Platinum and its alloys remain the state-of-the-art catalysts for selective nitric oxide production via ammonia oxidation. Yet improving efficiency, selectivity, and stability is a century-old challenge. Operando diffraction techniques are combined with mass spectrometry to investigate structural dynamics of ensemble and single α -Al 2 O 3 -supported Pt crystalline particles under realistic reaction conditions. Only by switching from ensemble averaging methods such as surface X-ray diffraction to single-particle sensitive Bragg coherent diffraction imaging can we identify distinct strain and morphology responses between particle types. Large and elongated particles exhibit annealing-induced misfit strain and a stable morphology during the reaction, while smaller, round, and low-strain particles display surface roughening and defect evolution at 400 °C, coinciding with enhanced NO selectivity. Notably, NH 3 exposure at 600 °C reverses facet strain. These findings highlight the critical role of nanoscale strain and morphology in catalyst performance and demonstrate the power of multi-techniques operando approaches to guide the design of next-generation catalytic materials. • Operando BCDI tracks strain evolution in single Pt nanoparticles during NH 3 oxidation. • Oxygen-rich and ammonia-rich regimes induce distinct defect and strain behaviors. • Structural response varies across particles, highlighting heterogeneity. • Strain in Pt nanoparticles evolve during NH 3 exposure at 600 °C. • Defect formation correlates with catalytic selectivity between NO and N 2 .

In response to the challenges posed by coastal erosion and rising sea levels, bio-inspired strucutres represent an innovative solution by combining physical protection with ecological benefits. This study investigates how key structural parameters, including tortuosity, surface roughness, porosity, and structural diversity, affect near-bed shear stress and turbulence around bio-inspired coastal defense modules.Wave flume experiments were conducted using fifty-one different modules, organized in three rows and tested under five monochromatic wave conditions (heights 2.5–10 cm, periods 1–2 s), scaled for Mediterranean deployment. Measurements from resistive wave gauges and Vectrino velocimeters were used to analyse wave energy dissipation, vertical current profiles, turbulence, and bed shear stress.Preliminary results show that structural geometry appears to influence local hydrodynamics, with implications for a better understanding of how the selected parameters affect the surrounding hydrodynamic conditions. The effects of the parameters are ranked to guide the development of efficient, multifunctional, bio-inspired coastal defense solutions. A combination of several of these parameters, within a single module and then at the scale of an entire structure, allowed us to explore the potential benefits of structural complexity in coastal protection systems.

The human visual system continuously extracts a wealth of dynamic information from the incoming retinal signal. One important task is the simultaneous tracking of multiple items that are moving within the visual environment. Past work has proposed that such multiple-object tracking relies on attentional resources that are location-based, i.e. resources are respectively associated with the individual items spatial positions. However, another possibility is that attentional resources are object-based, i.e. allocated to the combination of all items as an abstract shape configuration. Indeed, recent data suggests that during multiple-object tracking, the visual system continuously maintains a configuration represented by an illusory polygon formed by the shortest closed path connecting all tracked items. Here, we test this hypothesis by comparing signatures in the electroencephalographic (EEG) signal of 38 subjects with topological transitions of the polygon's shape. The topological transitions are qualitative changes in the polygon shape that go beyond mere quantitative changes in item positions (i.e., polygon corners). During object motion, the shapeshifting polygon can display switches between a convex and a concave shape. Concave shortest-path polygons can exhibit changes in the order in which the tracked objects are connected ('flips'). We demonstrate that topological transition events can be decoded from the ongoing EEG signal, revealing how the abstract configuration and its qualitative changes are represented throughout the tracking. Taken together, our work demonstrates that an object-based attentional mechanism is crucial during multiple-object tracking.

Purpose This study aims to examine the differentiated impact of a potential employer’s perceived corporate social responsibility (CSR) culture on multiple dimensions of organizational attraction. It explores how CSR culture, understood as a shared system of organizational values, influences potential candidates’ perceptions of attractiveness and their behavioural intentions in the job market. Design/methodology/approach A quasi-experimental, scenario-based single-factor study was conducted with 340 future graduates from two Canadian business schools. Drawing on signaling and social exchange theories, the research hypothesizes that CSR culture positively affects organizational attraction across both affective and behavioural outcomes. Findings The results indicate that perceived CSR culture has a significant impact on all organizational attraction measures. Participants exposed to a potential employer with a strong CSR culture reported an almost 20% higher probability of accepting a full-time job offer compared to those exposed to an employer with a weaker CSR culture. CSR culture also positively influences general attractiveness, perceived prestige and job intentions. However, it appears more effective in shaping affective attitudes and perceptions than in directly influencing job market behaviours. Originality/value To the best of the authors’ knowledge, this study is among the first to simultaneously assess the impact of a potential employer’s CSR culture across multiple dimensions of organizational attraction. By distinguishing affective and behavioural responses, it contributes to the theoretical debate on CSR signalling and highlights the strategic importance of CSR culture as a key organizational attribute that companies can leverage to enhance their attractiveness and expand their candidate pool.

Abstract In this paper, we present an experimental study of a new method based on Hot Hole Injection (HHI) for the embedded Select in Trench Memory (eSTM™) cell. An in-depth investigation of the floating implant provides insight into the erase mechanism. Electrical characterizations across the wafer reveal two distinct cell behaviors. The objective is therefore to identify the origin of these behaviors. It is demonstrated that no wafer-level effect is involved. Instead, this variability comes from process fluctuation of the Adjust threshold voltage (AdV T ) dose and the Lightly Doped Drain (LDD) depth. To optimize this new erase operation, a set of electrical characterizations are carried out on various process splits of the device. This enables the identification of a better trade-off that increases the cell’s erase probability. However, the optimized device has erasure failures. Future work should aim to achieve completely reliable operation (i.e. 100% of the expected behavior) while reducing the current consumption of the cells.

Abstract The perception of emotional faces plays a critical role in shaping human motor responses. However, the relationship between perceived facial expressions, particularly fear, and approach-related movement remains unclear as prior research often employed ambiguous approach behaviour and task requiring emotion identification before action planning, potentially introducing biases from differences in recognition accuracy across emotions. To address these limitations, we examined the effect of emotional faces (fear, angry, happiness) on unambiguous approach-related movement, i.e., forward single-step initiation by using a go/no-go paradigm. Moreover, two conditions were conducted: in the explicit condition, motor responses depended on whether the face was emotional or neutral, while in the implicit condition, they depended on the face’s gender. Results showed that the perception of emotional faces impacted forward single-step initiation in the explicit condition only. More precisely, the motor response was stronger (higher anticipatory postural adjustments amplitude) in front of fear and happy faces than angry faces, and faster (shorter anticipatory postural adjustments duration) to fear than to angry faces. Altogether, these results highlighted a movement improvement in front of a face which expressed fear compared to anger and, in a slightly more contrasting way, compared to happiness. These results supported the idea that fearful faces, although signalling threat, are associated with approach, whereas angry faces appear to be perceived as threatening and linked to avoidance movements.

Carbon (C) and nitrogen (N) are essential nutrients for coral–Symbiodiniaceae associations, yet global change can disrupt C and N acquisition by corals, affecting their resilience under stress. We investigated how two octocorals (Sarcophyton glaucum, Lobophytum sp.) and two hexacorals (Stylophora pistillata, Turbinaria reniformis) assimilate nitrogen from three 15N-labelled sources—dissolved free amino acids (DFAAs), Synechococcus (picoplankton), and Artemia salina nauplii (microplankton)—supplied at 1 µM N, under control (26 °C) and heat stress (30 °C) conditions. Corals were also incubated with natural pico-nanoplankton assemblages, with concentrations measured via flow cytometry. In addition, we measured the rates of photosynthesis and respiration, to estimate the relative contribution of autotrophy to the corals’ respiratory needs. Across all species, Synechococcus was the most efficiently assimilated N source, with uptake increasing under heat stress. Estimates of heterotrophic carbon assimilation (using C:N ratio) coupled with respiratory measurements showed that Synechococcus can provide 30–70% of the corals’ daily respiratory carbon demand, especially in the most heterotrophic species. Octocorals exhibited lower C and N assimilation rates than hexacorals, likely due to lower N needs and consistent with their overall lower metabolic requirements. Notably, S. glaucum displayed great flexibility in compensating reduced autotrophy through heterotrophy under heat stress. Incubations with natural plankton assemblages revealed increases in pico-nanoplankton concentrations in the presence of corals, likely stimulated by coral mucus release. These results demonstrate that picoplankton contributes significantly to both carbon and nitrogen budgets during heat stress and highlight species-specific nutritional strategies that may shape coral resilience under future climate conditions.