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Abnormal Child Behavior in primary school students: A Bayesian network analysis Le comportement anormal de l'enfant en école primaire : une analyse par réseau bayésien
Full text linkpeer reviewedThe Conners Teacher Rating Scale revised: short (CTRS-R: S) is a widely used psychometric instrument to screen for Attention Deficit and Hyperactivity Disorder (ADHD) as well as a broader construct of abnormal child behavior. In this study, we aimed to examine the network structure of abnormal child behavior using the CTRS-R: S in a sample of 525 French-speaking primary school students from Belgium. We employed Bayesian network analysis to estimate both the 28-item network and the network with the 8 items with the highest strength centrality, using the PC algorithm and bootstrapping to estimate the figures. Our study uncovered associations between inattention symptoms and learning disorders, shedding new light on the complexity of abnormal child behavior. We also identified different network structures, revealing a fresh perspective on the underlying mechanisms of these conditions. Our findings, though preliminary, are consistent with previous research and add to the burgeoning literature on Bayesian network analysis in abnormal child behavior research. Overall, our study underscores the complexity of the construct of abnormal child behavior and the importance of considering multiple factors in screening and diagnosis, emphasizing the need for a comprehensive approach to understanding and treating these disorders
Dynamic management of networks as revealed by DYNAVERSITY case studies
No full texteditorial reviewedIn the framework of the DYNAVERSITY project, 21 case studies lead to the identification of 4 main obstacles for crop diversity initiatives and 4 types of "bridges" (networking practices), that allow to ovecome those obstacles. Based on that analysis, 5 recommendations were formulated to support networking within and among crop diversity initiatives in Europe
A Resilient and Time-Efficient Approach to Product Development Through Availability-Based Design (ABD)
No full textpeer reviewedThe conventional design process (CDP) considers availability issues at the latest stages of the overall machine design project. Designers’ contributions are focused on technical and quality aspects. In most instances, other teams within the supply chain address delivery issues separately. Yet, current machine design projects are severely bound by deadlines, volatile, and sometimes uncertain. Due to the iterative nature of the design process itself, the number of potential design combinations is large. Their inherent technical checks and evaluations are highly time-consuming. In this paper, to avoid unnecessary design effort, the availability of components is considered at the early stages of the design process. This paper presents the Availability Based Design (ABD), which reorders the design process steps to preclude achieving a design that would be incompatible with the delivery time constraints. A ball screw drive actuator is used as a reference case study to quantitatively compare the performance of ABD to the CDP. The influence of key parameters is studied, including the availability ratio, the automation of key steps of the design process, the number of families of components and the number of technical checks necessary for validating a design. The performance assessment shows that ABD reduces the design time for availability ratios below 0.8 in manual design, and that automating the method makes ABD systematically faster than the CDP.9. Industry, innovation and infrastructure8. Decent work and economic growt
Rethinking “Evidence” in Traditional Medicine “Integration”
No full textpeer reviewedThis paper explores the concept of integration of traditional medicine through a multidisciplinary approach that combines medical humanities and pharmaceutical sciences. While it aligns with the World Health Organization’s (WHO) objective of fostering a harmonious and functional coexistence between conventional medicine and other
therapeutic practices to ensure optimal patient care, this paper critically examines the underlying rationale of the WHO’s strategy for achieving this integration. This logic is best illustrated by two of the central concepts that structure the WHO’s discourse on T&CM1: Integration and Evidence-Based. Both inform research-funding decisions, most notably in the cooperation for development sector, and have a decisive influence on public health
policies. In most parts of the world, the necessity for an evidence-based integration of T&CM functions like a mantra, rarely questioned by researchers within the medical or the social sciences, or by governmental and non-governmental actors. Consequently, the present paper problematizes the “evidence-based integration” of “traditional” medicines by challenging some of the key assumptions underpinning these concepts. In doing so, it
aims to identify and highlight several elements that may serve as guides on the way to ethically and epistemologically more sound frameworks for the co-existence of modern and traditional medicines
Elaboration and characterization of the structural, electrical, and piezoelectric properties of zinc oxide nanostructures for energy harvesting
No full textL'oxyde de zinc (ZnO) est depuis plusieurs décennies l’un des matériaux piézoélectriques les
plus prometteurs connus pour ses propriétés piézoélectriques en vue de la récupération de
l’énergie. Ce matériau vert peut être un substitut aux matériaux comportant des éléments
toxiques tels que le plomb.
Dans le cadre de cette activité de recherche, l’objectif ultime est de fabriquer des matériaux
dopés à l’Yttrium (Y) et non dopés à plusieurs échelles, notamment des couches minces
(élaborés par pulvérisation cathodique RF magnétron) et des nanofils (synthétisés en utilisant
une technique hydrothermale, à faible empreinte de carbone et respectueuse de
l’environnement), présentant une structure cristalline robuste et une microstructure orientée
verticalement. Nous avons étudié l’influence de la couche de germination en ZnO et le temps
de synthèse hydrothermale sur la croissance des nanofils, en particulier sur leur densité et leur
orientation.
Pour optimiser la couche de germination nécessaire à la croissance verticale des nanofils, deux
paramètres ont été analysés : le rapport argon/oxygène et l’épaisseur de la couche.
Les couches de germination et les nanofils obtenus ont été caractérisés par microscopie
électronique à balayage couplée à l’analyse dispersive en énergie des rayons X (eSEM/EDS),
par diffraction des rayons X (DRX) et par microscopie à force atomique (AFM). Les analyses
eSEM et AFM met en évidence l’organisation granulaire en surface de la couche de
germination, ainsi que la morphologie hexagonale caractéristique des nanofils. Tout en
présentant une composition élémentaire stœchiométrique.
Les propriétés électriques des structures obtenues ont également été évaluées par microscopie
à force atomique conductrice (CAFM) : les courbes I–V présentent des caractéristiques non
linéaires, confirmant la formation de contacts Schottky.
Enfin, le comportement piézoélectrique des NFs de ZnO a été étudié à la fois par microscopie
à force piézoélectrique (PFM). Un coefficient piézoélectrique d’environ 30 pm/V est obtenue
pour les NFs non dopés. Par contre, pour les NFs dopés à l’Yttrium, on observe un coefficient
plus fort de l’ordre de 57 pm/V
Distributionally robust nonnegative matrix factorization with self-paced adaptive multi-loss fusion
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Acyl thiosemicarbazides as novel inhibitors for zinc substrate in saline solution
Full text linkpeer reviewedThree acyl thiosemicarbazides, namely picolinoyl N4-phenylthiosemicarbazide (HL1), salicyloyl N4-phenylthiosemicarbazide (HL2), and anthraniloyl N4-phenylthiosemicarbazide (HL3), were synthesized and structurally characterized. Their corrosion inhibition performance on zinc substrates in 0.1 M NaCl solution was evaluated using polarization curves and electrochemical impedance spectroscopy (EIS). The interactions between the inhibitor molecules and the substrate surface, as well as the resulting corrosion products, were investigated using X-ray photoelectron spectroscopy (XPS), field-emission scanning electronic microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDS). Density functional theory (DFT) calculations were further employed to elucidate the relationship between the electronic properties of the compounds and their inhibitor mechanism. Electrochemical measurements confirmed that HL1, HL2, and HL3 acted as mixed-type inhibitors, with a predominant effect on the anodic dissolution of zinc. The inhibition efficiency of HL1 significantly increased from 46.47% at 1.0 × 10–5 M to 97.22% at 1.0 × 10–3 M, while at the same concentration (1.0 × 10–3 M), HL3 provided the highest protection efficiency (98.59%), followed by HL2 (97.82%) and HL1. Surface characterization and theoretical analysis revealed strong zinc-inhibitor interactions at the metal/oxide-solution interface, reflected by adhesion energy (Eadh) and summation of bond orders (SBO) calculations. The enhanced corrosion resistance of the zinc substrates was ascribed to the formation of zinc ion-inhibitor coordination complexes at the interface, which effectively hindered chloride ion penetration. Moreover, the superior performance of HL3 was rationalized by its stronger electron-donating character, as indicated by molecular electrostatic potential (MEP) and Fukui function analyses, and its stronger adhesion to oxidized zinc surfaces, supported by the most negative Eadh (–3.55 eV), the highest SBO (2.55), and the favorable alignment of its HOMO level with the valence band of ZnO
On the determination of the activation energies for the thermal relaxation of photoisomers by state-of-the-art mass spectrometry methods
Full text linkeditorial reviewedPhotoswitchable molecules are gaining prominence in scientific research due to their ability to switch structures and properties upon UV-Visible light absorption.1 Azobenzenes are a highly promising family of photoswitches thanks to their versatile synthesis which allows the modification of its properties such as the half-life time of the metastable photoisomers. This property is crucial, as it determines the applications targeted for the systems, ranging from the scale of the milliseconds to the year.2 Liquid chromatography-mass spectrometry (LC-MS) is used to study thermal back-isomerization kinetics in solution by monitoring the photoisomer population over time.3 Since back-isomerization follows first-order kinetics, the decay of metastable photoisomers is fitted with a mono-exponential to determine the rate constant at various temperatures and calculate activation energy. To extend the temperature range beyond solvent limits, we use a tandem ion mobility instrument to study gas-phase kinetics. Metastable ions are selected, trapped, and analyzed after relaxation at a given temperature to determine activation energy. Additionally, collisional activation is proposed to induce back-isomerization, monitored via ion mobility spectrometry on a Synapt G2-Si.
Several systems based on azobenzene (pristine and chemically modified) have been synthesized with peptoid backbones to tune properties such as the half-life of metastable photoisomers. Activation parameters (enthalpic and entropic contributions of the free Gibbs activation energy) were measured in methanol using our original LC/MS method. While enthalpy varies minimally, entropy emerged as a critical factor, with ΔΔS* reaching 50 J mol⁻¹ K⁻¹, consistent with insights by Reiman et al. on azobenzene’s thermal back-isomerization mechanism and addressing the so-called “entropy puzzle”.4 Tandem IMS was used to study thermal relaxation kinetics in the gas phase, revealing a complex interplay between structural features and desolvatation effects. While some systems displayed similar parameters in solution and gas phases, others indicated a shift in the back-isomerization mechanism, reflected in entropy differences.5 This technique enables fast screening of activation energies and mechanisms but is limited by the specialized equipment required. To address scalability, we propose to use a widespread activation method in mass spectrometry, the collisional activation CA, to trigger thermal back-isomerization in the gas phase via inelastic collisions. This process converts kinetic energy into internal energy and requires temperature calibration to determine kinetic parameters. These parameters are then derived by combining tandem ion mobility spectrometry (IMS) data with collision-induced isomerization, based on previous work by the Prell group on protein ions.6,7 (1) Kucharski, T. J.; Tian, Y.; Akbulatov, S.; Boulatov, R. Chemical Solutions for the Closed-Cycle Storage of Solar Energy. Energy Environ Sci 2011, 4 (11), 4449.
(2) Börjesson, K.; Lennartson, A.; Moth-Poulsen, K. Efficiency Limit of Molecular Solar Thermal Energy Collecting Devices. ACS Sustain Chem Eng 2013, 1 (6), 585–590.
(3) Tassignon, B.; Wang, Z.; Galanti, A.; De Winter, J.; Samorì, P.; Cornil, J.; Moth‐Poulsen, K.; Gerbaux, P. Site Selectivity of Peptoids as Azobenzene Scaffold for Molecular Solar Thermal Energy Storage. Chemistry – A European Journal 2023, 29 (70), e202303168.
(4) Reimann, M.; Teichmann, E.; Hecht, S.; Kaupp, M. Solving the Azobenzene Entropy Puzzle: Direct Evidence for Multi-State Reactivity. J Phys Chem Lett 2022, 13 (46), 10882–10888.
(5) Robert, T.; Henrard, G.; Tassignon, B.; Serez, A.; De Winter, J.; Dugourd, P.; Cornil, J.; Chirot, F.; Gerbaux, P. Back Isomerization Kinetics of Molecular Photoswitches: Complementary Insights from Liquid Chromatography and Ion Mobility Measurements. Anal Chem 2025, 97 (17), 9405–9413.
(6) Donor, M. T.; Mroz, A. M.; Prell, J. S. Experimental and Theoretical Investigation of Overall Energy Deposition in Surface-Induced Unfolding of Protein Ions. Chem Sci 2019, 10 (14), 4097–4106.
(7) Donor, M. T.; Shepherd, S. O.; Prell, J. S. Rapid Determination of Activation Energies for Gas-Phase Protein Unfolding and Dissociation in a Q-IM-ToF Mass Spectrometer. J Am Soc Mass Spectrom 2020, 31 (3), 602–610
