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Proceedings of the 6th International Conference on Electrical Engineering and Control Applications – Volume 2
No full textInternational audienceThis book gathers papers presented during the 6th International Conference on Electrical Engineering and Control Applications (ICEECA 2024), held on November, 19–21, 2024, Khenchela, Algeria. It covers new control system models, troubleshooting tips, and complex system requirements, such as increased speed, precision, and remote capabilities. Additionally, the book discusses not only the engineering aspects of signal processing and various practical issues in the broad field of information transmission, but also novel technologies for communication networks and modern antenna design. The later part of the book covers important related topics such as fault diagnosis and fault-tolerant control strategies for nonlinear systems and alternative energy sources. This book is intended for researchers, engineers, and advanced postgraduate students in the fields of control and electrical engineering, computer science, signal processing, as well as mechanical and chemical engineering
Coupled EBSD/TKD/APT study of segregation induced by irradiation in a Fe-13at.%Cr model alloy through different grain boundaries type
No full textInternational audienc
What Conception of Social Responsibility Does CSR Stand for? Reflections from Its Disciplinary Foundations
No full textFirst in situ application of a non-invasive sampling approach to assess pesticide effects on amphibian enzymatic activities
No full textInternational audienceAmphibians are particularly vulnerable to pesticide exposures, according to numerous laboratory and field studies. Enzymatic activities in biological tissues and body condition are usually proposed as relevant biomarkers for studying the effects of pesticides on these organisms, especially in agricultural context. Nevertheless, measuring enzymatic activities in animals often requires invasive sampling methods, such as blood sampling or destruction of individuals, in the case of juveniles in particular. Limiting the harmful effects of invasive methods and developing non-invasive approaches is crucial to the ethical principles that aim to minimize the impact on individuals. We aimed to test a non-invasive sampling approach, namely buccal swabbing, to investigate the effects of pesticides on the enzymatic activities of two native amphibian species, the common toad (Bufo bufo) and the green frog (Pelophylax sp.), in six ponds distributed along a pesticide contamination gradient. We also performed morphometric measurements to determine the body condition of the swabbed individuals. Our results show that buccal swabbing effectively allows quantifying the activities of 6 enzymes present in the saliva of wild amphibians and involved in neurological, non-specific immunity, and nutrition processes, supporting the relevance of this approach to assess their enzymatic responses in situ. Enzymatic levels of acetylcholinesterase, β-galactosidase, and β-glucosidase, as well as cytotoxic biomarkers, such as glutathione S-transferase, and peroxidases, were either significantly correlated with pesticide concentrations, or responsive to synchronicantagonistic effects of pesticide fluxes occurring in an agricultural constructed wetland. These results suggest that buccal swabbing in amphibians is applicable in the field for this purpose and that agricultural constructed wetlands could have the potential to affect aquatic fauna. Body condition was similar between ponds, regardless of the pesticide pressure level, probably because this variable reacts on longer time scales than enzymatic activities, or because of absence of effects, especially as this trait may be driven by other environmental factors. Our study highlights the relevance of using buccal swabbing to study the effects of pesticides on amphibians in the field while having limited impacts on animal welfare.</div
Search for β-delayed fission of Aug,m178 and an updated systematics in the region of neutron-deficient nuclei
No full textInternational audienceA search for a β-delayed fission (βDF) decay branch of isomerically pure samples of 178 Augand 178 Aum has been performed at the ISOLDE-CERN facility. Two complementary detectionsystems capable of registering α decays and fission fragments, the ISOLDE Decay Station and theASET (Alpha SETup), were used. Despite very high statistics of produced 178 Au nuclei, no fissionfragments were detected. Upper limits of βDF probabilities of PβDF (178 Aug ) < 1.11(2) × 10−8 andPβDF (178 Aum ) < 9.7(2) × 10−9 were determined. Corresponding lower limits of βDF partial half-lives were deduced as well, and the results are discussed in the context of experimental systematicsof βDF in the neutron-deficient region of the nuclear chart
Hybrid GPP–hospital control strategy for semi-solid extrusion 3D printing of ONC201 chewable units in pediatric oncology
No full textInternational audienc
Euclid Quick Data Release (Q1). First Euclid statistical study of galaxy mergers and their connection to active galactic nuclei
No full textInternational audienceGalaxy major mergers are indicated as one of the principal pathways to trigger active galactic nuclei (AGN). We present the first statistical analysis of the major merger and AGN connection in the Euclid Deep Fields, and showcase the statistical power of the Euclid data. We constructed a stellar-mass-complete (M_⋆>10^ M_⊙) sample of galaxies from the quick data release (Q1) in the redshift range z=0.5--2. We selected AGN using X-ray detections, optical spectroscopy, and mid-infrared (MIR) colours, and by processing observations with an image decomposition algorithm. We used convolutional neural networks trained on cosmological hydrodynamic simulations to classify galaxies as mergers and non-mergers. We found a larger fraction of AGN in mergers compared to the non-merger controls for all AGN selections, with AGN excess factors ranging from two to six. The largest excess we observed was in the MIR AGN. Likewise, a generally larger merger fraction (f_̊m merg) was seen in active galaxies than in the non-active controls, with the excess depending on the AGN selection method. Furthermore, we analysed f_̊m merg as a function of the AGN bolometric luminosity (L_̊m bol) and the contribution of the point-source component to the total galaxy light in the IE-band (f_ PSF ) as a proxy for the relative AGN contribution fraction. We uncovered a rising f_̊m merg, with an increasing f_ PSF up to f_ PSF ≃ 0.55, after which we observed a decreasing trend. In the range f_ PSF = 0.3--0.7, mergers appear to be the dominant AGN fuelling mechanism. We then derived the point-source luminosity (L_ PSF ) and showed that f_̊m merg monotonically increases as a function of L_ PSF at z<0.9, with f_ ̊m merg ≥50% for L_ PSF ≃ 2 . Similarly, at , f_̊m merg rises as a function of L_ PSF though mergers do not dominate until L_ PSF ≃ 10^ . For the X-ray and spectroscopically detected AGN, we derived the bolometric luminosity, L_ bol, which has a positive correlation with f_ merg for X-ray AGN, while there is a less pronounced trend for spectroscopically selected AGN due to the smaller sample size. At L_ bol AGN mostly reside in mergers. We conclude that mergers are most strongly associated with the most powerful and dust-obscured AGN, which are typically linked to a fast-growing phase of the supermassive black hole, while other mechanisms, such as secular processes, might be the trigger of less luminous and dominant AGN.</jats:p
Metabolomic analysis of macromycetes from French Guiana revueals chemodiversity in Xylariales order
No full textInternational audienceAn original approach was undertaken to explore the metabolomic variability of macroscopic fungi collected in French Guiana. Extracts from 160 specimens, representing 13 fungal orders, were analyzed using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The resulting metabolomic profiles enabled the construction of chemotaxonomic dendrograms, which successfully grouped most samples assigned to the order Xylariales and highlighted chemodiversity at both the genus and species levels within this lineage. Principal Component Analysis based on molecular family presence/absence revealed 35 discriminant clusters, including specific markers distinguishing Thamnomyces chordalis and Phylacia sp. Five previously undescribed natural products were isolated and structurally characterized: four polyketides-prochordapyrone (1) and chordapyrones A-C (2-4)-and one terpenoid, chordapyranone (5). Structural elucidation was accomplished through a combination of nuclear magnetic resonance (NMR) spectroscopy, circular dichroism and single-crystal X-ray diffraction. Based on structural and mechanistic considerations, a putative biosynthetic pathway was proposed for the formation of the polyketide compounds
Evolution of tribolayer in GH2132/GH4169 fretting wear at elevated temperatures
No full textInternational audienceTo investigate the development of the tribolayer in the GH2132/GH4169 superalloy pair, a systematic tangential fretting wear interruption test was conducted to analyze the microstructure, chemical composition, formation mechanism, and evolutionary characteristics of the tribolayer at 600℃. The results reveal that in the early stages of fretting, severe plastic deformation of material in the contact area and dislocation accumulation within the grains promote dynamic recrystallization and crack initiation, ultimately resulting in significant adhesive wear. As the test progresses, tribo-sintering of oxidized debris and continuous grain refinement give rise to a dense nanocrystalline tribolayer with enhanced hardness. This tribolayer, which is composed of nanocrystalline metal oxides, unoxidized nanograins, and amorphous phases, forms at the contact interface and serves as a mechanically and chemically robust barrier. It suppresses metal-to-metal contact, slows oxidation, and significantly reduces the wear rate, thereby stabilizing the worn surface
A review of corporate climate ratings: Assessing divergence from scientific expectations
No full textInternational audiencePrivate investment and consumption choices serve as a major driver to push companies to cut their greenhouse gas emissions and align their activities with the goal of reaching global Net Zero. Sustainability scores, labels and rankings have helped guide these decisions since the 1990s. They thus have significant leverage on defining future energy consumption and production, and, more generally, the upcoming low-carbon economy. Yet, such tools are now coming under increasing scholarly criticism. In this context, this study offers a review of issues raised by scholars, an inventory of climate-related scores, labels and ranking providers and their offerings, and an assessment of scores against best-in-class practices for each issue. The concerns raised in the scientific literature are related to the accuracy, reliability, and fairness of the tools, and whether they are effective in driving corporate action. Tool providers were found to use a diversity of business models, methodologies, and definitions of corporate climate performance. Despite some variability across tools and concerns, tools remain generally opaque and poorly aligned with scientific expectations. While corporate climate performance systems typically address indirect impacts and industry and size specificities; they rarely use standardized, verified inputs, and transparent, science-based weightings. Investors, corporations, and researchers can use our results to inform their choice of information providers, and regulators might take interest in the snapshot we provide on the maturity of the corporate climate performance measurement market. This paper aims to initiate improvements in the design of sustainability information systems