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This study aims to produce by robocasting leucite/zirconia pieces with suitable mechanical and tribological performance, convenient aesthetics, and antibacterial properties to be used in dental crown replacement. Leucite pastes reinforced with 12.5%, 25%, and 37.5% wt. ZrO 2 nanoparticles were prepared and used to print samples that after sintering were characterized in terms of density, shrinkage, morphology, porosity, mechanical and tribological properties and translucency. A coating of silver diamine fluoride (SDF) and potassium iodide (KI) was applied over the most promising material. The material's antibacterial activity and cytotoxicity were assessed. It was found that the increase of ZrO 2 reinforcement up to 25% enhanced both microhardness and fracture toughness of the sintered composite. However, for a superior content of ZrO 2 , the increase of the porosity negatively affected the mechanical behaviour of the composite. Moreover, the composite with 25% ZrO 2 exhibited neglectable wear in chewing simulator tests and induced the lowest wear on the antagonist dental cusps. Although this composite exhibited lower translucency than human teeth, it was three times higher than the ZrO 2 glazed material. Coating this composite material with SDF+KI conferred antibacterial properties without inducing cytotoxicity. Robocasting of leucite reinforced with 25% ZrO 2 led to best results. The obtained material revealed superior optical properties and tribomechanical behaviour compared to glazed ZrO 2 (that is a common option in dental practice). Moreover, the application of SDF+KI coating impaired S. aureus proliferation, which anticipates its potential benefit for preventing pathogenic bacterial complications associated with prosthetic crown placement. [Display omitted] • Three pseudoplastic leucite/ ZrO 2 pastes were robocasted for dental applications. • 25% ZrO 2 samples showed the highest microhardness and fracture toughness. • When tested against dental cusps they suffered and induced the lowest wear. • They showed lower translucency than teeth, but significantly higher than glazed ZrO 2. • SDF+KI coating provided antibacterial properties, without inducing cytotoxicity. [ABSTRACT FROM AUTHOR]

Les patients atteints de maladies inflammatoires chroniques et dysimmunitaires (lupus, polyarthrite rhumatoïde, psoriasis) présentent un surrisque cardiovasculaire à l'origine de la persistance d'une surmortalité grevant leur pronostic malgré une prise en charge spécifique de la maladie inflammatoire et/ou dysimmunitaire [1]. L'évaluation du risque cardiovasculaire des patients avec artérite à cellules géantes (ACG) reste à ce jour peu étudiée, notamment en France, et justifie une étude de grande ampleur en population française sur une longue période de suivi. Notre travail a pour objectif d'évaluer l'incidence des évènements cardiovasculaires chez les patients avec ACG en France, à partir des données nationales du Système National de Données de Santé (SNDS). Nous avons constitué une cohorte de patients présentant un diagnostic récent d'ACG entre janvier 2013 et décembre 2022. Ces patients avaient eu une hospitalisation avec un code CIM-10 d'ACG en diagnostic principal à partir des données du PMSI (Programme de Médicalisation des Systèmes d'Information). Nous avons consolidé le diagnostic en restreignant notre population aux patients ayant bénéficié d'une délivrance de corticothérapie d'au moins 1000 mg sur 40 jours dans l'année précédente ou après l'hospitalisation (données SNIIRAM, Système National d'Information Inter-Régimes de l'Assurance Maladie). Une population contrôle (appariée sur l'âge, le sexe et le département de résidence) provenant de la population générale a été constituée (entre 1 et 3 témoins par cas). Nous avons étudié la survenue des évènements cardiovasculaires majeurs (Major Cardiovascular adverse events (MACE), comprenant infarctus du myocarde (IDM), AVC, insuffisance cardiaque et décès de cause cardiovasculaire) et la mortalité toute cause confondue. Des analyses de survie comparatives entre les deux cohortes pour les principaux évènements cardiovasculaires et les décès ont été réalisée via un modèle de Cox, en ajustant sur le sexe, l'âge et les facteurs de risque cardiovasculaires. Nous avons aussi regardé l'effet de l'ACG sur la mortalité selon le temps écoulé depuis le diagnostic grâce à un polynôme fractionnaire de degré 2. 12 955 patients avec ACG et 33 685 témoins ont été analysés. L'âge moyen était de 74,3 ans chez les patients avec ACG et 73,7 ans chez les patients contrôles. La durée médiane de suivi était respectivement d'environ 46 et 49 mois. 4,3 % des patients avec ACG présentaient des complications ophtalmologiques. Nous avons mis en évidence un surrisque pour l'incidence des évènements cardiovasculaires majeurs (MACE, HR ajusté : 1,51 [1,41–1,62]), incluant l'IDM (1,58 [1,36–1,85]), les AVC (1,29 [1,14–1,47]), l'insuffisance cardiaque (1,41 [1,30–1,52]) et les décès cardiovasculaires (1,32 [1,16–1,51]) chez les patients avec ACG par rapport aux contrôles. Concernant l'incidence des facteurs de risque cardiovasculaires, nous avons retrouvé un surrisque pour l'hypertension artérielle (HR ajusté : 1,58 [1,46–1,70]), le diabète (1,64 [1,50–1,80]), l'AOMI (2,00 [1,79–2,23]) et le syndrome d'apnées du sommeil (2,20 [1,97–2,45]). Nous avons retrouvé un surrisque de décès toutes causes confondues chez les patients avec ACG (HR ajusté : 1,21 [1,15–1,27]), avec un surrisque mis en évidence principalement dans les 3 ans suivant le diagnostic. Cette étude met en évidence un surrisque de survenue d'évènements cardio-vasculaires (MACE) et d'apparition de facteurs de risques cardio-vasculaires chez les patients avec ACG suivis en France. C'est la plus grande étude à ce sujet dans notre pays. Malgré des données discordantes dans la littérature [2] , on retrouvait ici une surmortalité des patients avec ACG. Ce travail confirme donc la nécessité de dépister et prévenir ces évènements chez les patients âgés, souvent polypathologiques, présentant une ACG, notamment en dépistant et en prenant en charge les facteurs de risque cardiovasculaire. D'autres analyses doivent permettre de décrire l'imputabilité du terrain de chaque malade, et des stratégies thérapeutiques engagées, sur la survenue de ces évènements cardio-vasculaires. Ceci permettrait d'ajuster les prises en charge préventives et les stratégies thérapeutiques à chaque patient, dans l'idée d'une médecine personnalisée. [ABSTRACT FROM AUTHOR]

[Display omitted] • First-time appraisal of thermal diffusivity of cork along its main growth directions. • In-plane thermography and thermal ellipsometry assessment of natural cork on heating. • Insights on natural cork's thermal anisotropy and orientation-dependent variability. • Natural cork thermal conductivity measurements ranging from 0.033 to 0.048 W/(m·K). • Thermal anisotropy/ellipsometry of natural cork varies within a range of 23%. This study investigates the natural cork thermal anisotropy and its variability using plane slice samples of 1.4 mm thickness, cut along the principal radial, longitudinal, and tangential directions, from bark previously treated for cork stoppers production. Heating was pointwise applied to the rear face using a copper needle coupled to a Peltier element, while an in-plane thermographic technique monitored temperature evolution on the front surfaces using a Flir SC5650 infrared camera. Thermal diffusivity measurements yielded values of 0.172 ± 0.038 mm2/s (radial), 0.161 ± 0.022 mm2/s (longitudinal), and 0.160 ± 0.027 mm2/s (tangential). Additionally, a volumetric heat capacity of 0.25 MJ/(m3·K) was determined using the Hot Disk technique. This information enabled the calculation of thermal conductivity, ranging from 0.033 to 0.048 W/(m·K). Findings align with existing literature, which reports thermal diffusivity between 0.08 and 0.24 mm2/s and thermal conductivity between 0.035 and 0.045 W/(m·K). This study contributes valuable insights into the thermal properties of natural cork and their orientation-dependent variability. [ABSTRACT FROM AUTHOR]

Microwave heating technology is presented as an alternative to conventional stoneware firing, with focus on the crystallochemical transformations. Scanning electron micrographs of microwave fast-fired samples show similar features as those of conventionally fired in a natural gas kiln, taken as reference samples. Electrically fast-fired samples present incipient mullite type-II crystals, while in the microwave and conventionally (gas) fired samples it is fully formed. X-ray diffraction pattern show that the crystallochemical transformations occur at lower temperatures when samples are microwave fired, particularly for temperatures lower than the vitrification temperature. Kaolinite dehydroxylation is fully accomplished at 500 °C when the samples are microwave fired, being still incomplete at 800 °C in electrically fired samples. Stoneware crystallochemical and microstructural transformations point to lower microwave firing temperatures (up to 100 °C lower) than that required by electric firing. These observations are in good agreement with what is reported in the literature, explaining at the microscopic level what happens at the macroscopic level. [Display omitted] [ABSTRACT FROM AUTHOR]

Recent studies have suggested the existence of a correlation between the allochthonous units of NW Iberia (Galicia-Trás-os-Montes Zone - GTMZ) with SW Iberia (Ossa-Morena Zone – OMZ) in the European Variscan Belt. Such proposed equivalence is based on lithostratigraphic, tectono-metamorphic, geochronological, and geochemical affinities between these two domains, and implies that both zones had the same Neoproterozoic and early Palaeozoic basins, recording the same magmatic episodes and enduring the same tectono-metamorphic processes related to the Variscan Orogeny. As so, in order to better understand the evolution of these domains during the Ediacaran-Cambrian period, a comprehensive geochemical, isotopic and geochronological analysis of the metasediments that make up the OMZ and the allochthonous units of the GTMZ was carried out. The results show that the metasediments of OMZ and the Lower Allochthonous units of GTMZ present similar geochemical and geochronological features, having been likely deposited near each other, although small, but specific differences between both domains suggest that they do not correspond to the same depocentre. However, no geochemical, isotopic or geochronological correlation can be established with any of these domains and the Upper Allochthonous units of GTMZ. These metasediments display quite exotic features and, as such, were likely deposited in a different narrower basin, located to the W of the basins where OMZ and Lower Allochthonous units of GTMZ were deposited, thus providing precise constraints on the paleogeographic reconstruction of these domains during the Neoproterozoic to Early Ordovician dismembering of Gondwana. [Display omitted] • A comprehensive compilation of geochemical/geochronological data was done for the Iberian Massif. • Ediacaran metasediments from GTMZ Lower Allochthon and the OMZ are correlated. • There is no equivalence of the GTMZ Upper Allochthon to any sector of the OMZ. • There are no significant differences that indicate a subdivision of the OMZ. • Paleogeographic reconstruction for the Ediacaran-Cambrian is presented for NW Gondwana. [ABSTRACT FROM AUTHOR]

Leucite and zirconia are commonly used in the production of prosthetic dental materials. Leucite presents attractive optical properties but low toughness and wear resistance, which limits its use. Zirconia has much higher toughness, but due to aesthetic reasons and ageing issues, needs to be glass veneered. Chipping of such veneer is usually responsible for the abnormal wear induced on the antagonist teeth. Leucite reinforced with 25% of nano-zirconia is a promising alternative to overcome these issues, allowing the production of dental restorations without veneer. This study aims to investigate if leucite-zirconia composites have suitable optical, mechanical and tribological properties to be used in dental restoration. Samples with different compositions of leucite and/or nano-zirconia were produced by unidirectional compression and characterized concerning density, surface morphology, roughness, hardness, toughness, and translucency. Wear tests were performed in a chewing simulator using human cusps as counterbodies. Tests were also performed in glazed zirconia for comparison. 25% ZrO 2 leads to the lowest wear of the tribological pair among the studied systems, except 100% ZrO 2. This can be attributed to the toughening effect of zirconia and reduced size of third body particles. Abrasion was the main wear mechanism observed in this pair. In addition, this was the composite that presented the highest translucency. [ABSTRACT FROM AUTHOR]

The ban on the use of antibiotics in feed for broiler chickens in some parts of the world, coupled with increasing consumer demand for antibiotics-free poultry products, has in recent decades increased the interest of poultry researchers and producers to identify suitable alternatives to such antibiotics. One such alternative is yeast (S. cerevisiae). This review discusses the potential of probiotic and prebiotic yeast (S. cerevisiae) to increase productivity in healthy or disease-challenged broiler chickens. A brief description of the mechanisms of action, efficacy, reasons for inconsistent results, and ways to improve consistency in results are discussed. We conclude that there is convincing evidence that probiotic and prebiotic yeast products can replace in-feed antibiotics in broiler chicken production; however, there is a need for more testing in order to achieve consistency. A combination of appropriate yeast products alongside proper husbandry practices and bio-security measures could significantly reduce the observed inconsistencies, maximize broiler productivity and pave the way to a global antibiotic-free era in meat production. [ABSTRACT FROM AUTHOR]

Migmatite formation is dependent of several and inter-related factors, such as P-T conditions, protolith composition and the abundance of volatiles, which usually hinders the full understanding of anatectic progression and how it relates to orogenic evolution. We have constrained the petrological evolution of the anatectic complex (mostly metatexites and diatexites) of the Porto-Viseu Metamorphic Belt in the Central Iberian Zone (CIZ) using petrography, geochemical and isotopic data. Major and trace element geochemistry allowed us to conclude that the studied metatexites were formed through water-present melting of muscovite from metapelitic schists, whereas diatexites were mostly formed by dehydration-melting of muscovite and, occasionally, by the dehydration-melting of biotite. Additionally, melting evolution from incipient (metatexites) to pervasive (diatexites and anatectic granitoids) included SiO 2 enrichment and elemental depletion (except for Ca, P, Na and K). The geochemical evolution of these elements during melting progression was essentially controlled by fractionation/melting of plagioclase, K-feldspar, mica and apatite, whereas REE abundance was constrained by accessory minerals, such as monazite, apatite and zircon. In both cases, the geochemical control was variable and dependent on the fate of these mineral phases during the progression of melting, as well as the variable degree of melt loss or gain, with diatexites and granites being the result of substantial melt gain. The 87Sr/86Sr 320 values have a large dispersion (0.708–0.766), which is common for rocks that experienced these metamorphic conditions, whereas the εNd 320 values are less variable, roughly from −3 to −9 (diatexites: −8.24 to −2.96; metatexites: −8.79 to −5.15; staurolite-bearing schists: −7.57 to −5.19; granite: −8.21), being both isotopes independent of lithological type or degree of melting. Therefore, we interpret their Sr isotopic variation as mostly related to secondary alteration processes, whereas Nd isotopes, which are usually more immobile, should correlate to the initial protolith. In fact, their isotopic results are broadly consistent to the values of other CIZ metasediments that did not experience such high metamorphic conditions and melting (Douro-Beiras Supergroup), being most likely derived from these rocks, namely the Douro Group. [Display omitted] • Migmatites are complex and difficult to understand their formation. • PVMB metatexites formed by water-present melting of muscovite from schists • PVMB diatexites formed by dehydration-melting of muscovite and, rarely, biotite • REE patterns and isotope data similar to other Central Iberian Zone migmatites • Geodynamic setting (volcanic arc) and εNd similar to the Douro Group [ABSTRACT FROM AUTHOR]

Macroporous refractory ceramics were prepared with Al 2 O 3 -based particle stabilised foams in which ceramic particles were partially hydrophobized with propionic acid or l -leucine. Calcium aluminate cement (CAC) as dry powder or stable aqueous suspension were added as binders. Cement addition resulted in solid foams whereby setting took place in less than 24 h. Highly porous samples were attained with leucine-based foams whereas the propionic-acid ones were not stable after CAC addition. For leucine-based foams, fired samples with homogeneous microstructures, both high porosity (~80%) and cold crushing strength (~30 MPa) were attained when CAC aqueous suspension was used instead of CAC dry powder. These results were associated to the better dispersion of cement particles in the foam structure when CAC liquid binder was used and pointed out the advantages of this suspension for producing solid macroporous ceramics based on particle-stabilised foams. [ABSTRACT FROM AUTHOR]

Aiming at reducing the temperature of CaO.6Al 2 O 3 (CA 6) formation, SiO 2 , ZnO, and TiO 2 were evaluated as mineralizing agents in an Al 2 O 3 -CaCO 3 based macroporous thermal insulator. For the concentrations tested (0.6 mol% to 2.8 mol%), SiO 2 presented a small effect in the temperature of CA 6 formation. However, ZnO and TiO 2 favoured full CA 6 generation at 1400 °C, 200 °C below the reference composition. All analysed systems, besides 2.8Si, showed high porosity (> 80 %), suitable mechanical strength and expansion after firing at 1600 °C for 5 h. Softening temperature evaluation highlighted that ZnO- and TiO 2 -containing compositions could be used at higher temperatures than the SiO 2 ones. Thus, compositions containing 2.8 mol% of ZnO or TiO 2 were evaluated according to their thermal conductivity (k eff), showing lower k eff than the reference composition. Therefore, using these mineralizing agents, which are easily available, may provide reductions in the energy input to produce CA 6 -containing thermal insulators and benefits to all other required properties. [ABSTRACT FROM AUTHOR]

The interaction of amino acids (glycine, L-valine, L-isoleucine and L-leucine) with alumina surface was studied to induce partial hydrophobization and production of ultrastable particle-stabilised foams. The evaluation of these amino acids was carried out by mechano-quantum simulations followed by experimental tests (foamability, zeta potential, contact angle and foam lifetime measurements). The experimental results agreed with the trends pointed out by the simulations. The selected amino acids interact with alumina particles in aqueous media and in a broader pH range, leading to hydrophobization of surfaces, which was more intense for amino acids with higher molecular mass (isoleucine and leucine). As a consequence, ultrastable foams with a longer lifetime (> 100 h) were produced and the foam microstructure was preserved from ageing phenomena. Moreover, the attained foams were stable at different pH, opening up new possibilities to develop macroporous multiphasic ceramics, which can result in novel materials for thermal insulation at high temperatures. [ABSTRACT FROM AUTHOR]

A mechanism to explain the lower onset strengthening temperature induced by CaCO 3 in alumina-based macroporous ceramics is proposed, which relies on hydrocalumite-like phase formation during processing. Close to 600 °C, such phases are decomposed to lime and mayenite (12CaO·7Al 2 O 3), where the latter, due to its intrinsic nanoporosity and high thermal reactivity, generates bonds between the ceramic particles at ∼700 °C, resulting in microstructure strengthening. Based on this premise, the authors concluded that other Ca2+ sources could act similarly. Indeed, compositions containing Ca(OH) 2 or CaO showed the same effect on the onset strengthening temperature, which reinforces the proposed mechanism. The results attained indicated that macroporous insulators could be thermally treated at lower temperatures, just to acquire enough mechanical strength for installation, finishing in-situ their firing process. Besides that, lower sintering temperatures could be used to produce macroporous ceramics that would be applied in low thermal demand environments, e.g. aluminum industries. [ABSTRACT FROM AUTHOR]

A 2 × 2 factorial experiment was used to evaluate the effect of xylanase and sodium butyrate supplementation on performance, intestinal fermentation, histology, and morphometry in broiler chickens. A total of 384 Ross 308 broiler chicks (1-day-old) were allocated to 4 experimental treatments: CTR (control diet), XYL (CTR diet with 16,000 BXU/kg of xylanase), BUT (CTR diet with 1 kg/t sodium butyrate), and XYL+BUT (CTR diet plus xylanase and sodium butyrate). Each treatment had 8 replicates of 12 animals. Starter and grower diets, based on wheat and soybean meal, and water were available ad libitum. Body weight gain and feed intake were measured from 0 to 42 D, and feed conversion ratio corrected for mortality (FCR) was calculated. The profile of short-chain fatty acids in the duodenum, jejunum, ileum, and ceca digesta on days 21 and 42 was analyzed in addition to the relative weights of the different portions of the gastrointestinal tract (GIT). The villus height (VH), crypt depth (CD), and villus to crypt (VH: CD) ratio from the ileal tissue on day 42 were also evaluated. Statistical comparisons were performed using a 2-way ANOVA. Xylanase supplementation improved 42-D FCR by 5 points (P = 0.006), while butyrate did not affect 42-D FCR. On day 21, birds fed butyrate had heavier total GIT (P = 0.024), duodenum (P < 0.001), and jejunum (P = 0.025). Xylanase did not influence the relative weights in any intestinal section except the crop which was smaller in xylanase supplemented birds. At day 42, the VH: CD ratio was increased with sodium butyrate (P = 0.005). Supplementation of broiler diets with xylanase improved performance but had little effect on intestinal measures, whereas sodium butyrate influenced many of the intestinal indices with no consequence on animal performance. [ABSTRACT FROM AUTHOR]

Abstract Considering the production of stable CAC aqueous suspensions, this work addressed the action of gluconate anion as a Ca2+ complexing agent and retarder of CAC hydration. Using quantum simulations, the complexation energy of gluconate complexes was calculated. The pH range of stability for the complexes was estimated and aqueous suspensions containing CAC and sodium gluconate (NaG), stable up to 4 days at room temperature, were prepared. Afterwards, their hydration reactions were reactivated by adjusting the systems' pH. Results of solidification kinetics and mineralogical characterisation highlighted that, after reactivation, calcium aluminate hydrates were formed. Thermodynamics simulations indicated that using NaG up to 1 wt% would not be deleterious to the systems refractoriness up to 1700 °C. These systems could be applied in less explored processing routes for CAC-based refractory compositions (e.g. slip casting, direct foaming and additive manufacturing), resulting in innovations to produce advanced refractory ceramics. [ABSTRACT FROM AUTHOR]

• Dynamic cavity expansion model validated with finite element calculations. • Artificial viscosity approach to capture shock waves in porous metals. • Numerical methodology to replicate the distribution of voids in metals. • Cavitation fields dependent on average material properties. • Shock wave intensity dependent on local material properties. This paper investigates both theoretically and using finite elements the elastoplastic field induced by a pressurized spherical cavity expanding dynamically in an infinite medium modelled using the Gurson–Tvergaard–Needleman porous plasticity approach. The theoretical model, which assumes that the porosity is uniformly distributed in the material and the cavitation fields are self-similar, incorporates artificial viscous stresses into the original formulation of Cohen and Durban (2013b) to capture the shock waves that emerge at high cavitation velocities. The finite element calculations, performed in ABAQUS/Explicit (2013) using the Arbitrary Lagrangian Eulerian adaptive meshing available in the code, simulate the cavity expansion process in materials with uniform and non-uniform distributions of porosity. The finite element results show that the distribution of porosity has small influence on the cavitation velocity, as well as on the location of the shock wave, which are primarily determined by the cavity pressure and the average material properties. In contrast, it is shown that the intensity of the shock wave, evaluated based on the maximum value of the plastic strain rate within the shock, depends on the local material porosity. The ability of the theoretical model to reproduce the numerical results obtained for the various distributions of porosity used in this work is exposed and discussed. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of different environment conditions on productive performance and surface temperatures of Japanese quail (Coturnix coturnix japonica) during the initial stage of laying. In environmental controlled chambers, the birds were subjected to different temperatures and air velocities at the feeder. A total of 216 Japanese quails were distributed randomly in 2 galvanized wire cages, with 3 partitions each and 27 birds/cage. The experimental design consisted of randomized blocks with 2 treatments (air velocity at the feeder: 0, 1, 2, and 3 m/s and air temperature: 17, 23, 29, and 35°C) and 6 replicates. The productive performance was analyzed statistically (Sigma Plot 12.0) by 2-way ANOVA, with treatment means separated by the Tukey test (P < 0.05). To evaluate the main effects and interactions of the factors, the Holm–Sidak multiple comparisons test was performed using a mild condition as the control group (0 m/s). Feed intake did not differ (P > 0.05) among birds reared at temperatures of 23, 29, and 35°C, but higher feed intake was noted at 17°C. The mean values of egg production increased significantly (P < 0.05) with increased air velocity levels. It was observed that there was an increase in egg production and feed intake with the intensification of air velocity at the feeder, regardless of ambient temperature. Egg weight and feed conversion were not affected by air velocity treatments (P > 0.05). There was a significant positive correlation between air temperature and mean surface temperature and head surface temperature. In contrast, a significant negative correlation was observed between air velocity and mean surface temperature and head surface temperature. Productive performance was affected by temperature and air velocity, except for egg weight and feed conversion, which was not influenced by air velocity. Air velocity is important in removing heat from the surface of birds. [ABSTRACT FROM AUTHOR]