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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.

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.

La présente recherche s’inscrit dans la réflexion amorcée par les membres du Réseau québécois de recherche et de transfert en littératie pour se doter d’une définition commune qui rallie les conceptions des membres. La méthodologie de la recherche développement a permis d’encadrer le processus de conceptualisation de la littératie grâce à la coconstruction de savoirs, par les participants, tous experts chercheurs ou praticiens. Les résultats documentés de cette démarche, dont l’itération de ses phases de développement de savoirs ouvrent à une définition conceptuelle coconstruite de la littératie. Ils mettent en évidence la contribution de cette coconstruction sur l’appropriation et la diffusion de cette définition. This research builds a shared definition of literacy developed by both researchers and practitioners of the Quebec Network for Research and Transfer in Literacy, developed through the members’ conception of literacy. The research and development methodology allowed the conceptualization process to co-construct a definition of the term “literacy” by the participants who are experts in research or practitioners in literacy domain. The article documents the iterative process and development phases of designing the co-constructed definition of literacy. It underlines the importance of the contributions of theoretical and practical knowledge from the participant’s respective environments to adopt and disseminate the definition.

To compare the quantitative and qualitative lung perfusion data acquired with dual energy CT (DECT) to that acquired with a large field-of-view cadmium-zinc-telluride camera single-photon emission CT coupled to a CT system (SPECT-CT).A total of 53 patients who underwent both dual-layer DECT angiography and perfusion SPECT-CT for pulmonary hypertension or pre-operative lobar resection surgery were retrospectively included. There were 30 men and 23 women with a mean age of 65.4±17.5 (SD)years (range: 18-88years). Relative lobar perfusion was calculated by dividing the amount (of radiotracer or iodinated contrast agent) per lobe by the total amount in both lungs. Linear regression, Bland-Altman analysis, and Pearson's correlation coefficient were also calculated. Kappa test was used to test agreements in morphology and severity of perfusion defects assessed on SPECT-CT and on DECT iodine maps with a one-month interval. Wilcoxon rank sum test was used to compare the sharpness of perfusion defects and radiation dose among modalities.Strong correlations for relative lobar perfusion using linear regression analysis and Pearson's correlation coefficient (r=0.93) were found. Bland-Altman analysis revealed a -0.10 bias, with limits of agreement between [-6.01; 5.81]. With respect to SPECT- CT as standard of reference, the sensitivity, specificity, PPV, NPV, accuracy for lobar perfusion defects were 89.4% (95% CI: 82.6-93.4%), 96.5% (95% CI: 92.1-98.5%), 95.6% (95% CI: 90.9-97.8%), 91.4% (95% CI: 85.6-94.9%) and 93.0% (95% CI: 87.6-96.1%) respectively. High level of agreement was found for morphology and severity of perfusion defects between modalities (Kappa=0.84 and 0.86 respectively) and on DECT images among readers (Kappa=0.94 and 0.89 respectively). A significantly sharper delineation of perfusion defects was found on DECT images (P0.0001) using a significantly lower equivalent dose of 4.1±2.3 (SD) mSv (range: 1.9-11.85mSv) compared to an equivalent dose of 5.3±1.1 (SD) mSv (range: 2.8-7.3mSv) for SPECT-CT, corresponding to a 21.2% dose reduction (P=0.0004).DECT imaging shows strong quantitative correlations and qualitative agreements with SPECT-CT for the evaluation of lung perfusion.

Resume Introduction Il existe differents types de fixateurs externes (FE), sous forme sterile ou resterilisable. Ces dispositifs partiellement implantes ne suivent pas obligatoirement les regles de tracabilite sanitaire pour des raisons de faisabilite. L’objectif est de connaitre le type de FE reference dans les etablissements de sante et le type de tracabilite associee. Materiels et methodes Un questionnaire a ete adresse aux pharmaciens hospitaliers de la region Hauts-de-France, concernant le referencement et la tracabilite des FE dans leurs etablissements. Resultats Sur vingt etablissements, 65 % disposent de FE resterilisables et steriles a usage unique, 15 % uniquement des FE a usage unique et 20 % uniquement des FE resterilisables. Seuls quatre etablissements ont defini un nombre maximal de reutilisation des FE resterilisables. Pour les FE steriles, 75 % des etablissements realisent une tracabilite a but sanitaire et/ou logistique. Discussion Le referencement des FE steriles se developpe en complement ou en remplacement de FE resterilisables. Pour les FE resterilisables, la tracabilite sanitaire s’effectue souvent au plateau operatoire et non a l’element pose. De plus, le rythme de remplacement des differents elements n’est pas toujours defini. Les kits steriles sont une alternative simplifiant le circuit de tracabilite, bien qu’elle ne soit pas realisee dans tous les etablissements.

A simple model for the motion of shape-changing swimmers in Poiseuille flow was recently proposed and numerically explored by Omori et al. (2022). These explorations hinted that a small number of interacting mechanics can drive long-time behaviours in this model, cast in the context of the well-studied alga Chlamydomonas and its rheotactic behaviours in such flows. Here, we explore this model analytically via a multiple-scale asymptotic analysis, seeking to formally identify the causal factors that shape the behaviour of these swimmers in Poiseuille flow. By capturing the evolution of a Hamiltonian-like quantity, we reveal the origins of the long-term drift in a single swimmer-dependent constant, whose sign determines the eventual behaviour of the swimmer. This constant captures the nonlinear interaction between the oscillatory speed and effective hydrodynamic shape of deforming swimmers, driving drift either towards or away from rheotaxis., 10 pages, 4 figures

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Background Survival-based surrogate endpoints such as progression-free survival (PFS) are commonly used in oncology clinical trials. The evaluation-time bias in the assessment of median disease progression in randomized trials has been suggested by several simulation studies, but never demonstrated in the clinic. We aimed to demonstrate the existence of potential evaluation-time bias by assessing the impact of the timing of tumor assessments on median PFS from control arms without any active treatment of randomized controlled trials involving advanced cancer patients. Materials and methods A systematic literature search of English language publications from 1 January 2000 to 7 January 2021 was performed using MEDLINE (PubMed). Eligible trials for our meta-analysis included all randomized clinical trials evaluating anticancer drugs in adult patients with advanced cancers with a control arm without any anticancer drug consisting of best supportive care with or without a placebo. We performed a meta-regression analysis to analyze the correlation between the timing of the first tumor assessment and median PFS in patients randomized in the control arms without any active treatment. Results Of 3551 studies screened, 97 eligible trials were retrieved involving 36 747 patients, including 14 229 patients randomized into the control arms. A later first tumor assessment correlated with a prolonged median PFS (R2 = 0.44, P < 10−5). Conclusions Our results confirm the existence of potential evaluation-time bias in clinical research that had been suggested by simulation studies. The timing of tumor assessments should be kept the same in precision medicine trials using the PFS ratio as an efficacy endpoint., Highlights • Different timings for the evaluation of efficacy can induce an evaluation-time bias as suggested by simulation studies. • This bias can be an important issue in precision medicine trials that use each patient as their own controls. • In our meta-analysis, we found a correlation between the timing of the first tumor assessment and median PFS. • Our study confirms and quantifies the evaluation-time bias suggested by simulation studies. • Our study supports having timings of tumor assessments be kept the same in precision medicine trials.

Lead carbonates were used as cosmetic and pigment since Antiquity. The pigment, known as lead white, was generally composed of cerussite and hydrocerussite. Unlike most ancient pigments, lead white was obtained by a synthetic route involving metallic lead, vinegar and organic matter. Fermentation of organic matter produces heat and CO2 emission, leading to the formation of carbonates. As lead white is formed by trapping CO2, radiocarbon (14C) dating can thus be considered. We have developed a protocol to prepare lead white. We selected modern pigments for the experiment implementation and ancient cosmetic and paintings for dating. After characterization of the samples by XRD, thermal decomposition of cerussite at various temperatures was explored in order to select the appropriate conditions for painting samples. CO2 extraction yield, SEM and XPS were used to characterize the process. Thermal decomposition at 400°C was successfully applied to mixtures of lead white with other paint components (oil as binder, calcite as filler/extender) and to historical samples. We obtained radiocarbon measurements in agreement with the expected dates, demonstrating that thermal decomposition at 400°C is efficient for a selective decomposition of lead white and that paintings can be directly 14C-dated by dating lead white pigment.

Exploration of asteroid (101955) Bennu by the OSIRIS-REx mission has provided an in-depth look at this rubble-pile near-Earth asteroid. In particular, the measured gravity field and the detailed shape model of Bennu indicate significant heterogeneities in its interior structure, compatible with a lower density at its center. Here we combine gravity inversion methods with a statistical rubble-pile model to determine the density and size-frequency distribution (SFD) index of the rubble that constitutes Bennu. The best-fitting models indicate that the SFD of the interior is consistent with that observed on the surface, with a cumulative SFD index of approximately $-2.9$. The rubble bulk density is approximately $1.35$ g/cm$^3$, corresponding to a $12$% macro-porosity. We find the largest rubble particle to be approximately $145$ m, whereas the largest void is approximately $10$ m., 14 pages, 5 figures, accepted to Icarus

Abortion is common. Data on abortion rates are inexact but can be used to explore trends. Globally, the estimated rate in the period 2010-2014 was 35 abortions per 1000 women (aged 15-44 years), five points less than the rate of 40 for the period 1990-1994. Abortion laws vary around the world but are generally more restrictive in developing countries. Restrictive laws do not necessarily deter women from seeking abortion but often lead to unsafe practice with significant mortality and morbidity. While a legal framework for abortion is a prerequisite for availability, many laws, which are not evidence based, restrict availability and delay access. Abortion should be available in the interests of public health and any legal framework should be as permissive as possible in order to promote access. In the absence of legal access, harm reduction strategies are needed to reduce abortion-related mortality and morbidity. Abortion can be performed surgically (in the first trimester, by manual or electric vacuum aspiration) or with medication: both are safe and effective. Cervical priming facilitates surgery and reduces the risk of incomplete abortion. Diagnosis of incomplete abortion should be made on clinical grounds, not by ultrasound. Septic abortion is a common cause of maternal death almost always following unsafe abortion and thus largely preventable. While routine follow-up after abortion is unnecessary, all women should be offered a contraceptive method immediately after the abortion. This, together with improved education and other interventions, may succeed in reducing unintended pregnancy.

Having the means to share research data openly is essential to modern science. For human research, a key aspect in this endeavor is obtaining consent from participants, not just to take part in a study, which is a basic ethical principle, but also to share their data with the scientific community. To ensure that the participants' privacy is respected, national and/or supranational regulations and laws are in place. It is, however, not always clear to researchers what the implications of those are, nor how to comply with them. The Open Brain Consent (https://open-brain-consent.readthedocs.io) is an international initiative that aims to provide researchers in the brain imaging community with information about data sharing options and tools. We present here a short history of this project and its latest developments, and share pointers to consent forms, including a template consent form that is compliant with the EU general data protection regulation. We also share pointers to an associated data user agreement that is not only useful in the EU context, but also for any researchers dealing with personal (clinical) data elsewhere. © 2021 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.

Diminishing prospects for environmental preservation under climate change are intensifying efforts to boost capture, storage and sequestration (long-term burial) of carbon. However, as Earth's biological carbon sinks also shrink, remediation has become a key part of the narrative for terrestrial ecosystems. In contrast, blue carbon on polar continental shelves have stronger pathways to sequestration and have increased with climate-forced marine ice losses-becoming the largest known natural negative feedback on climate change. Here we explore the size and complex dynamics of blue carbon gains with spatiotemporal changes in sea ice (60-100 MtCyear