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The exceptional properties of Ti-6Al-4V of high strength, lightweight, corrosion resistance and machinability make it one of the most widely used alloys in in the aerospace industry. Significant efforts are underway to establish powder bed additive manufacturing technologies for Ti-6Al-4V. There are also increasing attempts to use thermal and cold spray to build near-net-shaped parts with buildup rates orders of magnitude higher than powder bed. Thermal spraying, such as HVOF, can oxidize and degrade the alloy due to the high processing temperature. Lowering the flame temperature through inert gas addition in full-size HVOF systems is a possible approach to retain solid-state deposition of the feedstock particles, thereby limiting oxidation and detrimental α-case formation, while providing sufficient heat input for particle softening and plastic deformation at impact. Novel miniaturized HVOF systems, with spray jets of only a few millimeters in width, may further offer the possibility to improve the spatial resolution of the buildup for near-net shape forming. The process parameter range for solid-state deposition of Ti-6A-4V using the liquid-fuelled TAFA Model 825 JPid and the novel hydrogen-fuelled Spraywerx ID-NOVA MK-6 with the addition of nitrogen is shown. Buildups at over 80% deposition efficiency generally yield as-sprayed porosities below 3% and hardness above 200 HV100gf. Attainable microstructures and oxygen content as a function of spray parameters are delineated. Recrystallization and beta-annealing of selected samples lower the residual porosity and can create equiaxed α and intergranular ß-phases. Ultimate tensile strengths of up to 1100 MPa were attained; however, the residual oxygen content of above 0.7% was found to limit β-phase formation, which contributes to a limited elongation to failure.

Carbonaceous asteroids, such as (101955) Bennu, preserve material from the early Solar System, including volatile compounds and organic molecules. We report spacecraft imaging and spectral data collected during and after retrieval of a sample from Bennu’s surface. The sampling event mobilized rocks and dust into a debris plume, excavating a 9-meter-long elliptical crater. This exposed material is darker, spectrally redder, and more abundant in fine particulates than the original surface. The bulk density of the displaced subsurface material was 500 to 700 kilograms per cubic meter, which is about half that of the whole asteroid. Particulates that landed on instrument optics spectrally resemble aqueously altered carbonaceous meteorites. The spacecraft stored 250 ± 101 grams of material, which will be delivered to Earth in 2023.

Aircraft gas turbine blades operate in aggressive, generally oxidizing, atmospheres. A solution to mitigate the degradation and improve the performance of such components is the deposition of thermal barrier coatings (TBCs). Specifically for bond coats in aerospace applications, High Velocity Air Fuel (HVAF) is very efficient for coating deposition. However, internal diameter (ID) HVAF has received little attention in the literature and could be a promising alternative to limit oxidation during spraying when compared to conventional methods. The main objective of this study is to analyze how the ID-HVAF process influences the microstructure of NiCoCrAlY coatings. To that end, an i7 ID-HVAF torch is used to deposit NiCoCrAlY splats on a steel substrate with different stand-off distances. The deposited splats showed the presence of craters, and both partially melted and deformed particles at the surface. The particle velocity data was recorded, and the splat deformation and amount of particles deposited was shown to be directly corelated to the stand-off distance. The material composition analyzed and quantified by Energy Dispersive Spectroscopy (EDS) did not reveal any traces of in-flight of particle oxidation, but further investigation is required. This study provided a preliminary understanding towards the importance of stand-off distance on the splat deformation and in-flight oxidation.

Multi-layered thermal barrier coatings (TBCs) are deposited on gas-turbine metallic components to protect them against high temperatures, oxidation, and corrosion. However, TBCs have limited working temperatures and lifetimes due to their material properties. Several approaches are being tested to increase TBC topcoats' phase stability and properties. Increasing entropy to stabilize phases is a concept introduced in 2004 and required decreasing the Gibbs free energy. Many high-entropy ceramics are being developed for structural and functional applications, and high-entropy oxides (HEOs) are promising TBC ceramics due to their unique characteristics. HEOs are single-phase solid solutions that contain five or more cations, usually a mixture of transition metals and rare earths. Due to the cocktail effect, the final material has a different behavior from its constituents, making it a viable method to improve the properties of traditional materials. Generally, high entropy materials are characterized by three additional phenomena: sluggish diffusion, severe lattice distortion, and high entropy. A review of possible improvements in the lifetime of TBC topcoats using different HEOs in terms of their composition, properties, and stability are presented here. Different HEOs are then examined and various thermophysical properties, high-temperature stability, and sintering resistance are discussed.

Due to the aggressive operation conditions of turbine hot sections, protective coatings are required to provide oxidation and hot corrosion resistance for superalloy components. Thermal barrier coatings (TBCs) are comprised of a ceramic top coat and a metallic bond coat (BC) and are typically used as thermal protection systems against these aggressive environments. Conventional BC materials are MCrAlX, with M being metals or alloys (e.g., Ni, Co or NiCo) and X being reactive elements such as Y, Hf, Ta, Si. Due to their strength, thermal stability, and oxidation resistance, high-entropy alloys (HEAs) have presented promise for use as BC materials in hightemperature applications. Owing to its cocktail effect, optimally chosen HEAs could help to enhance the hot corrosion resistance of BCs by forming a more continuous, dense, and uniform thermally grown oxide (TGO). Furthermore, HEAs could help to control the diffusion between the bonding layer and substrate in elevated temperature environments. This paper will discuss the thermodynamic, mechanical, and microstructural behaviour of HEAs. Furthermore, the selection and usage of HEAs as BCs will be explored and compared to conventional BCs in TBC systems.

Thermal-sprayed coatings have been extensively used in aerospace with the main purpose to overcome critical challenges such as abrasive wear, corrosion, and erosion under high temperatures and pressures. Such protective coatings can also play a crucial role in optimizing the efficiency of gas turbine engines and therefore in reducing fuel consumption and CO2 emissions. CuAl-based thermal sprayed coatings are commonly employed in tribological interfaces within gas turbine engines to improve the fretting wear resistance. These coatings are typically deposited by more traditional thermal spray techniques such as Air Plasma Spray (APS), which can result in high amounts of oxidation within the coating. The main purpose of this study is to critically evaluate lower temperature deposition techniques such as High Velocity Oxygen Fuel (HVOF). More specifically, commercially available Cu-10Al powders were deposited by APS and HVOF and compared in terms of their microstructural, mechanical properties, and tribological behavior at various temperatures. The results showed that the friction coefficient for both coatings was equivalent at room temperature while it was lower for the APS coating at high temperature. Similarly, the specific wear rates showed little difference between the different deposition processes at room temperature while the APS coating had a lower wear rate at elevated temperature when compared to the HVOF coating. The differences in the friction and wear behavior were attributed to differences in the interfacial processes.

Background: The monogenic forms of Parkinson's disease represent less than 10% of familial cases and a still lower frequency of sporadic cases. However, guidelines to orient genetic testing are lacking. We aim to establish the interest of multiplex ligation-dependent probe amplification as a primary screening test and to propose clinical criteria to guide genetic diagnostic tests for patients with suspected Mendelian Parkinson's disease.Methods: We recruited 567 patients with parkinsonism from 547 unrelated families and performed two multiplex ligation-dependent probe amplifications for each. We confirmed all pathogenic G2019S variants in the LRRK2 gene by Sanger sequencing and screened the PRKN gene for a second mutation in cases of one heterozygous structural variant in the PRKN gene.Results: The performance of multiplex ligation-dependent probe amplifications was 51/567 (9%) for the entire cohort and included 27 (4.8%) LRRK2 G2019S mutations, 19 (3.4%) PRKN mutations, and 5 (0.9%) SNCA locus duplications. The variables significantly associated with a positive test in the total cohort were North African ancestry (p < 0.0001), female sex (p = 0.004), and younger age at onset (p < 0.0008).Conclusions: Retrospective analysis allowed us to refine our indication criteria: (i) North African ancestry, (ii) an age at onset < 40, or (iii) a familial history of parkinsonism with at least one affected first-degree relative. Our study highlights the interest of MLPA testing for other parkinsonisms cases with a family history, especially for patients with dementia with Lewy bodies or a multiple system atrophy-like phenotype.

Estuaries and deltas are crucial zones to better understand the interactions between continents and oceans, and to characterize the mineralization and burial of different sources of organic matter (OM) and their effect on the carbon cycle. In the present study, we focus on the continental shelf of the northwest Mediterranean Sea near the Rhône river delta. Sediment cores were collected and pore waters were sampled at different depths at one station (Station E) located on this shelf. For each layer, measurements of dissolved inorganic carbon concentration (DIC) and its isotopic composition (δ13C and Δ14C) were conducted and a mixing model was applied to target the original signature of the mineralized OM. The calculated δ13C signature of the mineralized organic matter is in accordance with previous results with a δ13COM of marine origin that is not significantly impacted by the terrestrial particulate inputs from the river. The evolution with depth of Δ14C shows two different trends indicating two different Δ14C signatures for the mineralised OM. In the first 15 cm, the mineralized OM is modern with a Δ14COM = 100 ± 17‰ and corresponds to the OM produced during the nuclear period of the last 50 years. Deeper in the sediment, the result is very different with a depleted value Δ14COM = –172 ± 60‰ which corresponds to the pre-nuclear period. In these two cases, the marine substrate was under the influence of the local marine reservoir effect with more extreme Δ14C results. These differences can be largely explained by the influence of the river plume on the local marine DIC during these two periods.

There are numerous ways to control objects in the Stokes regime, with microscale examples ranging from the use of optical tweezers to the application of external magnetic fields. In contrast, there are relatively few explorations of theoretical controllability, which investigate whether or not refined and precise control is indeed possible in a given system. In this work, seeking to highlight the utility and broad applicability of such rigorous analysis, we recount and illustrate key concepts of geometric control theory in the context of multiple particles in Stokesian fluids interacting with each other, such that they may be readily and widely applied in this largely unexplored fluid-dynamical setting. Motivated both by experimental and abstract questions of control, we exemplify these techniques by explicit and detailed application to multiple problems concerning the control of particles, such as the motion of tracers in flow and the guidance of one sphere by another. Further, we showcase how this analysis of controllability can directly lead to the construction of schemes for control, in addition to facilitating explorations of mechanical efficiency and contributing to our overall understanding of non-local hydrodynamic interactions in the Stokes limit., Comment: 30 pages, 9 figures

Dans une perspective de promotion des pratiques éducatives inclusives en milieu préscolaire, ce texte fait la synthèse des recensions antérieures d’études sur la collaboration, la concertation, la coopération et le partenariat. L’analyse de ces recensions antérieures précise les principaux concepts appliqués à différents domaines : scolaire, travail d’équipe-école, milieux cliniques… Ces relations antérieures mettent en valeur l’importance des relations de collaboration et de concertation dans l’établissement d’un partenariat interorganisme. Parmi les avantages, le travail en collaboration favorise une hausse de la capacité de développer, d’optimiser, d’améliorer, d’accélérer et de changer les façons de faire de l’organisation : l’amélioration de la qualité des services. Les auteurs terminent en relevant les pistes de recherche et de développement en matière d’éducation inclusive. Ils retiennent un modèle de programme virtuel de perfectionnement comme outil d’apprentissage à la collaboration et au partenariat et de développement de pratiques d’inclusion des enfants ayant des besoins particuliers., To promote inclusive educational practices in the pre-school milieu, this text synthesizes previous reviews of studies on collaboration, co-development, cooperation, and partnership. The analysis of these reviews specifies the main concepts applied to the different domains: school, school-team work, clinical milieux. …These prior relationships highlight the importance of collaboration and co-development in the establishment of an inter-organization partnership. Among the advantages, working in collaboration promotes increased ability to develop, optimize, improve, accelerate and change the way the organization does things, thus improving the quality of services. The authors conclude by pointing out research and development avenues for inclusive education. They describe a model of an online professional development tool that teaches collaboration, partnership and the development of inclusion practices for special needs children., Desde una perspectiva de promoción de prácticas educativas inclusivas en el medio preescolar, éste texto presenta una síntesis de recensiones anteriores de estudios sobre la colaboración, la concertación, la cooperación y la asociación. El análisis de dichas recensiones identifica los conceptos principales aplicados a los diferentes campos : escolar, trabajo, equipo escolar, medios clínicos… Estas relaciones subrayan la importancia de las relaciones de colaboración y de concertación en el establecimiento de una asociación entre organismos. Entre las ventajas, el trabajo en colaboración favorece una alta capacidad de desarrollo, de optimización, de perfeccionamiento, de aceleración y de transformación de los métodos de la organización : mejorar la calidad de los servicios. Los autores concluyen identificando las pistas de investigación y de desarrollo en materia de educación inclusiva. Retienen un modelo de programa virtual de perfeccionamiento en tanto que útil de aprendizaje de la colaboración, de la asociación y del desarrollo de practicas de inclusión de los niños que presentan necesidades particulares.

Dorénavant, l’école se doit de développer une culture nourrie par la collégialité de tous les acteurs qui amène la direction de l’école et les enseignants à oeuvrer ensemble comme collègues tout en cherchant à être apprenants les uns des autres dans l’amélioration de leur potentiel, voire du potentiel de l’équipe tout entière (Gather-Thurler, 2000). Cette équipe devrait fonctionner comme une communauté d’apprentissage où les membres apprennent les uns des autres et où le leadership est exercé à tour de rôle par les diverses personnes en tenant compte de leurs préoccupations à un moment donné. La question qui se pose est la suivante : comment peut-on favoriser un tel mode de fonctionnement? Cet article fait état d’une recherche où l’utilisation de la dynamique causale a servi à mieux définir les facteurs favorables à l’implantation réussie d’une communauté d’apprentissage professionnelle. Le groupe a identifié plusieurs facteurs qui ont été regroupés de la façon suivante : 1) le leadership de la direction d’école et des enseignants, 2) des attitudes positives pour travailler en collaboration telles que l’ouverture d’esprit, l’engagement, la volonté de partager ses connaissances, de s’entraider ainsi que de prendre des risques, l’humilité pour remettre en question le statut quo, le respect des autres, la confiance, 3) les ressources, 4) le temps pour discuter et échanger, 5) les données sur les résultats des élèves. Cet écrit fournit également aux directions d’école des occasions de réflexion sur la façon de transformer leur rôle pour laisser plus de place au dialogue collaboratif., Schools must develop a culture nourished by collegiality, leading administrators and teachers to work together as colleagues while learning from each other and improving their potential, and therefore the potential of the entire team (Gather-Thurler, 2000). This team should function as a learning community where members learn from each other and where a variety of people take turns as leaders, depending on the concerns at any given moment. The following question was asked: How can this type of working method be promoted? This article describes research using the causal dynamic to better define factors that would encourage the successful implantation of a professional learning community. The group identified several factors, grouped together as follows: 1) leadership of school administration and teachers, 2) positive attitudes for working in collaboration, such as open mindedness, commitment, the desire to share knowledge and help each other and take risks, the humility to question the status quo, respect for others, trust, 3) resources, 4) time for discussions and exchanges, 5) data on student results. This article also offers school administrators opportunities for reflection on how to transform their roles in order to leave more room for collaborative dialogue., De ahora en adelante, la escuela debe desarrollar una cultura alimentada por la colegialidad de todos los actores, lo que conduce a la dirección de la escuela y a los maestros a trabajar en tanto que colegas que tratan de aprender unos de otros a mejorar su potencial, incluso el potencial de todo el equipo (Gather – Thurler, 2000). Ese equipo deberá funcionar como una comunidad de aprendizaje en la cual los miembros aprenden los unos de los otros y en la cual las diversas personas ejercen el liderazgo cada quien a su turno, tomando en consideración sus preocupaciones a un momento dado. La cuestión que surge es la siguiente: ¿Cómo se puede favorecer esa manera de funcionar? Este artículo rinde cuentas de una investigación en la cual la utilización de la dinámica causal sirvió a mejorar la definición de los factores favorables al logro de la implantación de una comunidad de aprendizaje profesional. El grupo identificó varios factores que fueron reagrupados de la siguiente manera: 1) el liderazgo de la dirección de la escuela y de los maestros, 2) las actitudes positivas para trabajar en colaboración tales que la amplitud de miras, el compromiso, la voluntad de compartir sus conocimientos, de ayudarse mutuamente y de correr riesgos, la humildad de cuestionar el estatus quo, el respeto de los demás y la confianza, 3) los recursos, 4) el tiempo par poder discutir e intercambiar, 5) los datos sobre los resultados de los alumnos. Este texto ofrece asimismo a la dirección de las escuelas la ocasión de reflexionar sobre la manera de transformar su rol para otorgar más espacio al dialogo colaborativo.

Background In the "treat-to-target" era, the development of non-invasive markers to assess endoscopic healing in ulcerative colitis (UC) is essential. Fecal calprotectin (FC) and intestinal ultrasound (IUS) are alternatives to colonoscopy to assess UC activity. The objective of this study was to evaluate the performance of IUS and FC to assess endoscopic mucosal healing in UC patient. Methods All consecutive patients between January 2021 and August 2022 with UC who underwent (1) a complete colonoscopy (2) an intestinal ultrasound and/or (3) a fecal calprotectin (4) within 4 weeks were included in a prospective cohort. Bowel wall thickness (BWT) and color doppler signal (CDS) were assessed on each segment. Endoscopic mucosal healing was defined by a MAYO score of 0-1. Results A total of 57 patients were included, 57.9% had endoscopic healing (22/57 MAYO 0 and 11/57 MAYO 1). Thirty-two (56.1%) were female, the median age and disease duration were respectively 43 years (IQR, 30-58) and 29 years (IQR, 18-39). Respectively 16 (16/57, 28.1%) and 41 (41/57, 71.9%) patients had BWT < 3 mm and an absence of Doppler signal. The sensitivity (Se), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of BWT < 3 mm to predict endoscopic mucosal healing were 37%, 77%, 72% and 44%. The association of the absence of CDS with normal BWT did not modify these performances. The same values for fecal calprotectin < 150 µg/g were respectively 81%, 78%, 84% and 74%. The association of a fecal calprotectin < 150 µg/g, with a BWT < 3mm and the absence of Doppler signal increased the specificity and the PPV (Se 33%, Sp 94%, PPV 89%, VPN 48%). The same values were found for patients classified as MAYO 0 or MAYO 0-1 (Table 1). Conclusion The combination of intestinal ultrasound and fecal calprotectin is effective to identify endoscopic mucosal healing in UC.