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The extensive study and development of additive manufacturing technologies have allowed not only increased customization of the final parts but especially of their complexity. From such perspectives, intricate and mechanically efficient lattices which maximize their strength-to-weight ratio could be printed. Nevertheless, the fabrication of regular lattices, like octet cells, has been proven to be particularly limited by the layer-by-layer construction process due to the introduction of additional interfaces and/or the requirement of supports. In this work, a hybrid extrusion–photopolymerization process is coupled with a 6-axis robotic arm to allow for the fabrication of layers-less lattices thanks to the use of a custom graphical user interface and control over the printing head orientation. A highly reactive resin is employed as the ink and loaded with silica particles in order to tailor its rheological properties. A good resemblance between the printed components and the digital model is achieved, while their mechanical properties are superior to the ones of the traditionally additive manufactured octets.

FeFe hydrogenases are the most efficient H2-producing enzymes. However, inactivation by O2remains an obstacle that prevents them being used in many biotechnological devices. Here, we combine electrochemistry, site-directed mutagenesis, molecular dynamics and quantum chemical calculations to uncover the molecular mechanism of O2diffusion within the enzyme and its reactions at the active site. We propose that the partial reversibility of the reaction with O2results from the four-electron reduction of O2to water. The third electron/proton transfer step is the bottleneck for water production, competing with formation of a highly reactive OH radical and hydroxylated cysteine. The rapid delivery of electrons and protons to the active site is therefore crucial to prevent the accumulation of these aggressive species during prolonged O2exposure. These findings should provide important clues for the design of hydrogenase mutants with increased resistance to oxidative damage.

Le syndrome de platypnée-orthodéoxie (SPO) associe la présence d’une dyspnée (platypnée) et d’une désaturation (orthodéoxie) à l’orthostatisme alors qu’elles sont absentes au décubitus. Le SPO est le plus souvent dû à un shunt intracardiaque tel qu’un foramen ovale perméable (FOP), auquel s’ajoute un facteur favorisant fonctionnel. Il survient chez des patients de plus de 50ans. Son diagnostic est simple et repose sur la mesure de la saturation en décubitus et à l’orthostatisme et sur la mise en évidence des facteurs favorisants par la réalisation d’une échocardiographie. Le traitement recommandé est la fermeture du FOP lorsqu’il est présent. Nous présentons le cas d’un patient ayant présenté un infarctus cérébral sur embolie paradoxale au travers d’un FOP responsable d’un SPO.

Background/Objectives:Urinary biomarkers of hydration (urine osmolality, UOsm; urine specific gravity, USG) follow circadian variations. For individuals, researchers and health-care professionals, there is value in identifying time frames during which spot values of UOsmand USGare representative of 24-h values in healthy young adults.Subjects/Methods:Eighty-two free-living adults (22.3±2.9 years, 22.2±1.5 kg/m2) collected individual urine voids over a 24-h period. UOsmand USGwere measured on each void and on the pooled 24-h sample. To determine the time of day when a spot sample was likely to be equivalent to the 24-h value, daytime voids were binned by time and equivalence was tested for each 2-h window. Equivalence was a priori defined as being within 100 mOsm/kg (UOsm) and within 0.003 units (USG) of 24-h values.Results:For both UOsmand USG, voids between 1400 and 2000 hours produced values that were equivalent to the 24-h sample, whereas earlier voids tended to overestimate 24-h UOsmand USG. For windows 1401–1600 hours, 1601–1800 hours and 1801–2000 hours, the mean difference (95% confidence interval) between spot and 24-h UOsm(mOsm/kg) was −25 (−72; 22), 28 (−35; 92) and 12 (−41; 66), respectively, whereas for USGthe difference was 0.0014 (−0.0028; −0.0001), 0.0001 (−0.0017; 0.0019) and 0.0005 (−0.0018; 0.0009), respectively.Conclusions:In free-living healthy French adults, 24-h urine concentration can be approximated from a mid- to late-afternoon spot urine sample. This finding suggests that an afternoon sample may be an accurate and practical tool for hydration monitoring, useful to individuals and health-care practitioners.

La frecuencia del estrabismo infantil es del 5%. El estudio de los reflejos corneales y las pruebas de oclusión son las exploraciones clave para el diagnóstico. En la mayoría de los casos, la esotropía es precoz o adquirida (de acomodación). El cerebro del recién nacido es muy plástico y vulnerable, y el estrabismo puede provocar una ambliopía (disminución de la agudeza visual del ojo no fijador). Es necesario determinar la refracción con cicloplejía para determinar el error refractivo. La prescripción de lentes correctoras es la primera etapa del tratamiento y el estrabismo debe ser alternante para prevenir la ambliopía.

La thrombectomie mécanique a montré son efficacité dans la prise en charge des patients victimes d'un accident vasculaire cérébral (AVC) secondaire à une occlusion artérielle proximale (1). Néanmoins, chez 12-34% des patients traités, la revascularisation est insatisfaisante (TICI < 2b) en fin de procédure (2), avec 40% des cas sans aucune modification de la configuration de l'occlusion (3). Le stenting intracranien est une option intéressante pour ces occlusions réfractaires (4), mais présente des contraintes liées au risque hémorragique dans un contexte ischémique aigu pouvant être majoré par la mise en place d'antithrombotiques pour prévenir la thrombose intrastent. L'objectif de cette étude était d’évaluer le rôle du stenting intracrânien dans la prise en charge des patients pris en charge pour une occlusion artérielle proximale réfractaire, en analysant l'issue clinico-radiologique des patients stentés appariés à une population n'ayant pas bénéficié de stenting.

Nous rappelons quelques résultats expérimentaux récents concernant la dynamique des fronts eutectiques lamellaires en solidification directionnelle d'échantillons minces. Ces résultats ont permis à la fois de répondre à des questions théoriques relevant de la phénoménologie des fronts de propagation unidimensionnels (1D) et de résoudre quelques problèmes métallurgiques. Nous nous proposons d'aborder maintenant la dynamique des fronts de solidification eutectique lamellaire en échantillons massifs (fronts 2D). Nous esquissons un tableau des phénomènes nouveaux que nous nous attendons à observer dans de tels échantillons.

The number of new cases of emerging fungal infections has increased considerably in recent years, mainly due to the large number of immunocompromised individuals. The objective of this study was to evaluate the susceptibility of emerging fungi to fluconazole, itraconazole and amphotericin B by disk diffusion method. In 2015, 82 emerging fungi were evaluated in IPB-LACEN/RS and 13 (15.8%) were resistant: 10/52 were from superficial mycoses and 3/30 from systemic mycoses. The data from the study point to the need for permanent vigilance regarding the careful evaluation in the prescription and clinical and laboratory follow-up of patients affected by fungal infections.

We studied the formation and growth of locked-lamellar microstructures in a thin sample of a slightly hypoeutectic Al-Al2Cu alloy. The coupled-growth dynamics, including early stages and steady-state regimes, was observed optically in real time during directional solidification. The orientation of the α (Al) and θ (Al2Cu) crystals was measured ex situ in a series of eutectic grains by X-ray Laue microdiffraction. A nucleation event of a θ crystal on a pre-existing α crystal, and the subsequent growth of a eutectic grain with a type-C orientation relationship, that is, with a coincidence of {123}-α and {100}-θ planes, were observed in situ. In type-C eutectic grains, lamellar locking occurred parallel to the low-energy coincidence plane. A regular (floating) coupled-growth dynamics was observed in misoriented eutectic grains.

We present an in-situ experimental investigation of irregular eutectic growth dynamics observed optically in real time during directional solidification (DS) and rotating directional solidification (RDS) of a model transparent alloy, namely Amino-methyl-propanediol-Succinonitrile (AMPD-SCN). The SCN-rich solid grows with a nonfaceted solid-liquid interface, while AMPD forms thin whisker-like faceted crystals. With RDS, we observed simultaneously four distinct growth dynamics along the solidification front thanks to the rotation induced velocity ramp. At low velocity, AMPD crystals grow individually, with their leading tip ahead of – at a higher temperature than – the SCN-liquid interface which presents a linear undercooling change with V ramp. This regime is defined as a quasi-steady decoupled growth. During RDS, AMPD crystals are found to rotate with the sample in this regime. When they can reach the unsteady coupled-growth regime at higher V, since increasing V favors the formation of AMPD-SCN-liquid trijunctions, they start to branch noncrystallographically. At higher velocity, impurity effects lead to the formation of two-phase fingers. Further increase in the velocity results in the formation of primary SCN dendrites and a fine interdendritic eutectic microstructure. DS experiments confirmed the existence of those regimes at different velocities.

•Intracranial aneurysms are diagnosed in up to 9% of patients with sickle cell anemia, while consensual approaches to treatment of unruptured intracranial aneurysms in this population are still lacking.•A standardized hematological preparation protocol was undertaken before each aneurysm treatment.•Overall, endovascular and surgical treatment seems safe and effective: successful treatment was documented in 95% of aneurysms, while all 6 post-procedural complications were transitory or reversible, without residual deficits at one-year follow-up.•We suggest using stenting as a last therapeutic resort due to the potential high rate of ischemic complications in this population.

Growing evidence suggests a distinction between water intake necessary for maintaining a euhydrated state, and water intake considered to be adequate from a perspective of long-term health. Previously, we have proposed that maintaining a 24-h urine osmolality (UOsm) of ⩽500 mOsm/kg is a desirable target for urine concentration to ensure sufficient urinary output to reduce renal health risk and circulating vasopressin. In clinical practice and field monitoring, the measurement of UOsmis not practical. In this analysis, we calculate criterion values for urine-specific gravity (USG) and urine color (UCol), two measures which have broad applicability in clinical and field settings. A receiver operating characteristic curve analysis performed on 817 urine samples demonstrates that a USG⩾1.013 detects UOsm>500 mOsm/kg with very high accuracy (AUC 0.984), whereas a subject-assessed UCol⩾4 offers high sensitivity and moderate specificity (AUC 0.831) for detecting UOsm>500 m Osm/kg.

Distal vessel occlusions represent about 25 % to 40 % of acute ischemic stroke (AIS), either as primary occlusion or secondary occlusion complicating mechanical thrombectomy (MT) for large vessel occlusion. However, the benefit of MT remains uncertain for these occlusions.

Owing to the high complexity of diatom community data, there is a special need for methods accounting for complex non-linear gradients. A Kohonen's self-organizing map (SOM) is a neural network with unsupervised learning. It allows both unbiased classification of the communities and visualization of biological gradients on a two-dimensional plane. However, as with other neural networks, many parameters must be set. A new R-package with a SOM parameterization specifically suited to diatom communities has been developed. Further developments will consist of creating a graphical user interface in order to make this method easier to use for the scientific community.