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Collaboration and hierarchical interference within a French Cité educative
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Reference equations for quadriceps strength, endurance and power: a multicentre study
No full textInternational audienceIntroductionThe lack of reference values of lower-limb muscle function hinders the clinical recommendations of its measurement in patients with COPD. Therefore, this study aimed to develop reference equations to predict reference values for quadriceps strength, endurance and power and evaluate their construct validity in patients with COPD.MethodsQuadriceps strength, endurance and power were assessed in 158 healthy individuals and 87 patients with COPD. In addition, patients with COPD performed a 6-min walk test (6MWT) and a 1-min sit-to-stand test (1STS). Multiple linear regressions were performed to develop reference equations. The proportion of patients with COPD with reduced quadriceps function was determined, and correlations between quadriceps strength, endurance and power expressed in percentage of predicted values and 6MWT and 1STS performance were used to document the construct validity of the reference equation.ResultsExcept for quadriceps isometric endurance, the proposed reference equations explained 50–70% of the variance of the quadriceps properties in healthy individuals. All quadriceps properties were systematically reduced in a large proportion of patients with COPD compared to healthy individuals. Correlation coefficients between quadriceps properties expressed in percentage of predicted values and 6MWT and 1STS performance ranged between 0.28 and 0.49 (all p<0.05).ConclusionIn healthy individuals, age, sex, height and body mass index explained 50–70% of the variance of quadriceps strength, endurance and power. When expressed in percentage of predicted values, these quadriceps properties correlated with 6MWT and 1STS performance, suggesting construct validity of the reference values in patients with COPD
NMR kinetic monitoring of the bio-based cutting fluid organic waste's hydrolysis during immobilization in alkali-activated materials
No full textInternational audienceThe direct incorporation of low viscosity vegetable oil (OL) such as sunflower oil into fresh geopolymers (GP) is easier than for mineral oil. This corresponds to a suitable dispersion of the oil in the form of fine micrometric droplets. 1H NMR studies have shown that during the formulation time at liquid state, no surfactant is formed (by hydrolysis due to the basic nature of the solution) and the easy incorporation of the vegetable oil into the fresh geopolymer is due to the property of the oil (viscosity, polarity, surface tension, etc.) rather than the surfactant action of saponification products. The kinetic monitoring of the chemical evolution of sunflower oil in contact with the activating solution was carried out by 1H NMR spectroscopy at room temperature. The NMR study confirmed that the percentage of disappearance of triglycerides was correlated with the percentage of production of fatty acids, and that the saponification reaction was complete in 4 days. The evolution of the sunflower oil trapped in the geopolymer was carried out by grinding and extraction operations in petroleum ether and in water. 1H NMR has shown using both triglyceride disappearance or glycerol production that saponification reaction occurs (45 % hydrolysis in 7 days), even if oil is trapped into solid geopolymer
Palladium-NHC mediated telomerization of aromatic alcohols
No full textInternational audienceThe telomerization reaction of dienes with alcohols mediated by organopalladium complexes represents a versatile method to convert butadiene into value-added chemicals. The use of aromatic alcohols in the telomerization is still an under-explored area that has attracted increased interest in recent years. In this contribution, we examine the catalytic behaviour of a series of well-defined palladium N-heterocyclic carbene precatalysts (Pd-NHC) in the telomerization of butadiene with aromatic alcohols. The process was optimized by studying the influence of Pd/L ratio, of the base and of the pre-catalyst structure. The versatility of the method was tested employing a series of aromatic alcohols, including lignin-type phenols. In the context of biomass valorisation, an explorative study on the telomerization with lignin was carried out
Price elasticity of housing supply in France: a multi-level estimation
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Adaptive transfer learning using SegFormer for imbalanced pixel in medical image segmentation
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The Analysis of Workplace Conflicts to Question the Well-Being of Professionals in the Healthcare and Social Care Sector in France
No full textInternational audienceMany scientific disciplines have long since seized the term "well-being", associating it with other related notions such as happiness, quality of life, or satisfaction. Its use by sociologists is much more recent, with questions of legitimacy, definition, and methodology arising acutely, as the established boundaries of well-being are linked to the individual, their subjectivity, and their health - physical, mental, and social - according to the definition given by the WHO (World Health Organization) in 1948. This research falls within a completely different perspective: to articulate subjectivity and objectivity, reposition the individual within their interactions and contexts of action, and move away from the medical perspective to align with a sociological perspective, consistent with the mentioned choices.This study examines well-being through the lens of workplace conflicts. By adopting an interactionist and phenomenological perspective, we aim to understand the subjective dimension of professional experiences. Contextualizing this experience will facilitate its objectification by collecting data on the work environment and employment conditions. The understanding of the conflict dynamics at play and the underlying issues will help identify the factors detrimental to workplace well-being. The analysis of the absence of conflictual experience and the various associated factors will, conversely, bring to light the contours of workplace well-being. The survey was conducted in 2023 on a representative sample of professionals working in the healthcare and social care sectors. The results are based on the analysis of 728 questionnaires collected in northern France
Effets d’un dispositif de réalité virtuelle immersive sur la rééducation du membre supérieur chez des enfants et adolescents atteints de paralysie cérébrale : un essai contrôlé randomisé
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Probing the water adsorption and stability under steam flow of Zr-based metal-organic frameworks using <sup>91</sup>Zr solid-state NMR spectroscopy
No full textInternational audienceThe stability of metal–organic frameworks (MOFs) in the presence of water is crucial for a wide range of applications, including the production of freshwater, desiccation, humidity control, heat pumps/chillers and capture and separation of gases. In particular, their stability under steam flow is essential since most industrial streams contain water vapor. Nevertheless, to the best of our knowledge, the stability under steam flow of Zr-based MOFs, which are among the most widely studied MOFs, has not been investigated so far. We explore it herein for three UiO-like Zr-based MOFs built from the same Zr cluster but distinct organic linkers at temperature ranging from 80 to 200 °C. We demonstrate the possibility of acquiring their 91Zr NMR spectra using high magnetic field (18.8 T) and low temperature (140 K) and of interpreting them by comparing experimental data with NMR parameters calculated by DFT. NMR observation of this challenging isotope combined with more conventional techniques, such as N2 adsorption, X-ray diffraction, IR, and 1H and 13C solid-state NMR spectroscopies, provides information not only on the possible collapse of the MOF framework but also on the adsorption of molecules into the pores. We notably show that UiO-66(Zr) and UiO-66-Fum(Zr) built from terephthalate and fumarate linkers, respectively, are stable over 24 h (and even over 7 days for UiO-66(Zr)) under steam flow at all investigated temperatures, whereas UiO-67-NH2 containing a 2-amino-[1,1′-biphenyl]-4,4′-dicarboxylate linker degrades under steam flow at temperatures ranging from 80 to 150 °C but is preserved at 200 °C. The lower stability of UiO-67-NH2 stems from its larger pores and its weaker Zr–O coordination bonds, whereas its preservation at 200 °C results from a more limited condensation of water in the pores