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Superhydrophobic surfaces are known for their drag reduction properties. However, the interface between the lubricant and the overlying flow may easily become unstable, leading to the depletion of the superhydrophobic layer and to a consequent drag increase. In this paper, we investigate the modal and non-modal instability of the flow over longitudinal trapezoidal superhydrophobic riblets, including, for the first time, the gas/liquid interface dynamics in the stability analyses. A two-dimensional stability problem, obtained with a domain transform technique and interface modelling using a linearised Young–Laplace equation, is coupled with the n−periodic stability framework introduced by Schmid et al. (2017). The latter technique, using a Bloch wave formalism, allows the computation of the stability of an array of n riblet units of given periodicity at a reasonable numerical cost. For small periodicities, the most unstable mode is a fundamental instability stemming from the three-dimensionalisation of a Tollmien–Schlichting wave. Conversely, in the case of large riblet periodicities, a subharmonic mode linked to capillarity effects becomes the most unstable. Nonmodal transient growth analysis shows that the superhydrophobic riblets have a weak effect on the overall growth. However, riblets having small periodicities induce a slight stabilisation of the flow, while large ones induce an increase of the energy growth on detuned perturbations. The resulting energy growth mechanism induces interface deformations encompassing more than one subunit.

Introduction Effective communication has been shown to improve patients’ health outcomes. This study utilizes medical improvisation techniques to teach communication skills to different groups of health students (nurses, midwives, medical doctors, speech therapists). Objectives Our objective was to design and compare an interprofessional workshop that incorporates applied improvisation to train different groups of healthcare students in communication skills, resilience, dealing with failure and empathy. Medical improvisation is an innovative concept to prepare healthcare students to be more effective communicators. Methods Required medical improv workshops (using applied improvisational theater techniques) were held for first to third-year students in France and in Hungary. Workshop evaluations were obtained before and following the last session and at 3 months post-workshop for one cohort. The courses incorporated role plays, listening, storytelling and verbal/ nonverbal exercises to help students communicate with empathy and clarity. The two countries used the same questionnaires for assessment (Interpersonal Communication Questionnaire and Intolerance Uncertainty Scale) Results 24 medical students participated in the Hungarian improvisation workshops, and 26 speech therapists students in the French improvisation workshops. In the finished Hungarian research over 90% of students rated the workshops as above average or excellent. Students reported a gain in insights regarding their role as a clinician (≥ 90%), an improvement in their ability to demonstrate effective communication (80–87%), and a positive impact on teamwork (91–93%). At 3 months post-workshop, students reported they had used at least 1 improvisation skill on their clinical wards. Both countries can claim promising results so far in their separate studies, our results comparing the French and Hungarian data using synchronized scales and questionnaires is currently in progress, and will be processed by the end of this year. Conclusions This study demonstrates that medical improvisation exercises can be scaled to different fields of healthcare students in various years of their studies and that using improv in healthcare education is universal in its short and long-term effects. Further, we found that students felt that it improved their communication. This study also provides new insights regarding specific improvisation exercises that are most useful for the clinical environment. Keywords: Improvisation. Medical improvisation. Applied Improvisation. Medical education. Communication. Uncertainty tolerance. Soft skills training Disclosure of Interest None Declared

Geopolymers are promising ecofriendly materials for temperature-resistant applications. For this purpose, the synthesis of thermally resistant, alkali-activated binders based on metakaolin with additives (silica sand, calcite and mullite) has been studied. In this work, the stabilities of the mechanical and thermal properties of geopolymer binders based on metakaolin with additives during scale transfer are investigated. The geopolymer is prepared by mixing metakaolin, silica sand, calcite and mullite with two different alkaline silicate solutions. The scale-up process does not affect the processing conditions. After the temperature tests at the laboratory and pilot scales (two ramps selected 200 and 400 °C/min) the same phases crystallized (leucite, wollastonite and kalsilite), and the microstructure (viscous flow formation) is the same, thus confirming the scalability of the formulation. These different results show that these formulations displaying a value of 50 MPa and λ = 1.45 W m−1 K−1, are promising for fire protection and fire resistance applications.

The impact of metakaolin mixtures on geopolymer formation and corresponding properties was evaluated by synthesizing geopolymers from mixtures of different metakaolins and 5 M potassium silicate. Mixture reactivity was investigated by viscosity, thermogravimetric (DTA-TGA), and in situ infrared spectroscopy (FTIR) measurements. Furthermore, mechanical strength and porosity measurements were undertaken on consolidated materials. The results have shown that the aluminum molar concentration governs the setting time and oligomer formation energy. Indeed, the high aluminum content associated with the high purity of the metakaolins lead to a low formation energy of oligomer, whereas for the metakaolins containing more impurities, the energy required for oligomer formation was higher. Regardless of the formulation, the mechanical strength and porosity trends were similar. Network characteristics were assessed by amorphous material content and in situ infrared spectroscopy (FTIR) analysis. It was demonstrated that (i) for Si/Al 1.5, different networks are formed. The zeta potential values of the different metakaolin mixtures corroborated these findings. Zeta potential values of metakaolins are governed by the impurities present in the metakaolins, which limit the release of aluminous species from the metakaolins in solution, emphasizing that knowledge of raw materials is essential to understand the local networks formation.

IntroductionIn humans, adversity in childhood exerts enduring effects on brain and increases the vulnerability to psychiatric diseases. It also leads to a higher risk of eating disorders and obesity. Maternal separation (MS) in mice has been used as a proxy of stress during infancy. We hypothesized that MS in mice affects motivation to obtain palatable food in adulthood and changes gene expression in reward system.MethodsMale and female pups from C57Bl/6J and C3H/HeN mice strains were subjected to a daily MS protocol from postnatal day (PND) 2 to PND14. At adulthood, their motivation for palatable food reward was assessed in operant cages.ResultsCompared to control mice, male and female C3H/HeN mice exposed to MS increased their instrumental response for palatable food, especially when the effort required to obtain the reward was high. Importantly, this effect is shown in animals fed ad libitum. Transcriptional analysis revealed 375 genes differentially expressed in the nucleus accumbens of male MS C3H/HeN mice compared to the control group, some of these being associated with the regulation of the reward system (e.g., Gnas, Pnoc). Interestingly, C57Bl/6J mice exposed to MS did not show alterations in their motivation to obtain a palatable reward, nor significant changes in gene expression in the nucleus accumbens.ConclusionMS produces long-lasting changes in motivation for palatable food in C3H/HeN mice, but has no impact in C57Bl/6J mice. These behavioral alterations are accompanied by drastic changes in gene expression in the nucleus accumbens, a key structure in the regulation of motivational processes.

Abstract An optimized sol–gel protocol was carried out to produce an yttrium aluminum garnet (YAG) xerogel from aluminum alkoxide and an yttrium salt on a semi-pilot scale. This xerogel was successfully used without prior pyrolysis as a solid load with the aid of additives in the preparation of pastes. Thermal treatment of the green bodies, obtained by robocasting of the paste, led to cohesive single-phase YAG ceramics. Manufacturing ceramic pieces by additive methods will allow shaping complex forms, while the single step conversion/consolidation would simplify the technological process, reducing global energy costs. Since YAG possesses high strength and good creep behavior at high temperatures, these refractory pieces could replace the metal alloys used in turbine blades for deep space exploration. Structural, thermal and chemical characterizations were performed on xerogel powders, pastes, and YAG ceramics.

To optimize the use of hollow‐core photonic crystal fibers (HC‐PCF), their cores are filled with an atomic gas for an ultra‐enhanced interaction with an incident laser beam in applications such as atomic vapor microcells. One challenge in these gas‐filled HC‐PCFs is to control the physiochemical interactions between the gas medium and the silica inner surface of the fiber core surround. In this work, thus, the processing of ceramic coatings on glass substrates by chemical solution deposition is focused on. Also, the successful implementation of an original coating procedure for a deposition inside hollow‐core fibers with complex microstructures is described. It is indeed possible to form a thin, dense, inorganic, and amorphous layer with a low thickness, low roughness, and high transparency. To obtain such a result, several parameters must be controlled, including the concentration of the solution, the technique and the deposition time, as well as the heat treatment undergone by the fiber. In particular, the selected aluminosilicate coatings, which are nonporous and present a 20–30 nm thickness, demonstrate a considerable improvement of the lifetime properties of the fibers filled with rubidium vapor, without modifying its original guiding properties. [ABSTRACT FROM AUTHOR]

Background: Hydatidosis is a major health problem is many countries. It is a parasitic disease that can affect adults as well as children. Hydatid cyst often involves the lungs in children. Given the anatomical and physiological differences between children and adults, generalization from adult studies is inappropriate. Methods: To determine particularities of lung echinococcosis in children, we conducted a retrospective study of all cases treated for hydatid cyst of the lung at our department. Results: One hundred fifteen children (average age, 7 years 6 months; range, 3–15 years) were managed for pulmonary hydatid cyst, which corresponds to 66% of all hydatid localizations. Male predominance was noted (sex ratio=1.94). Cough (60.9%) and chest pain (59.1%) were the most common clinical features. Fever and fatigue were noted in 57 (49.5%) and 34 (29.5%) cases, respectively. Giant cysts were seen in 11 patients (10%). The cysts were mostly diagnosed when they are intact (68.7%). Mixed hepatic and pulmonary cysts were noted in 27 cases (4.25%). Conservative muscle-sparing surgery was performed in all cases. Complications were noted in 20% of the cases. Conclusion: As hydatidosis has a different pattern in children, optimal management requires a better knowledge of its particularities in this age group.

Recent years have seen an increase in research focusing on the amelioration of apple pomace waste for use in the food and nutraceutical industries. Much of this work has concentrated on the characterisation of the polyphenol composition of apple pomace materials to determine their role in conferring nutritional and health benefits. Although apples contain substantial quantities of polymeric procyanidins (condensed tannins), this class of compounds has received limited attention in apple research. This study quantified the polymeric procyanidins in apple pomace extracts using a rapid, methyl-cellulose precipitation (MCP) approach for the first time. In addition, a non-targeted metabolomics approach was applied to determine the most abundant phenolic classes present. Polymeric procyanidins were found to be the most abundant type of polyphenol in apple pomace extracts and were generally oligomeric in nature. Multivariate statistical analysis revealed that the ferric-reducing antioxidant power (FRAP) was most strongly correlated with the polymeric procyanidin concentration. Noting that polymeric procyanidins may not cross the cell layer to exert antioxidant activity in vivo, their presence in apple pomace extracts may therefore overestimate the FRAP. This work highlights the importance of polymeric procyanidins in the phenolic diversity of apple pomaces, and it is proposed that in future studies, rapid MCP assays may be used for their quantification.

Caffeic acid (CA) exhibits a myriad of biological activities including cardioprotective action, antioxidant, antitumor, anti-inflammatory, and antimicrobial properties. On the other hand, CA presents low water solubility and poor bioavailability, which have limited its use for therapeutic applications. The objective of this study was to develop a nanohybrid of zinc basic salts (ZBS) and chitosan (Ch) containing CA (ZBS-CA/Ch) and evaluate its anti-edematogenic and antioxidant activity in dextran and carrageenan-induced paw edema model. The samples were obtained by coprecipitation method and characterized by X-ray diffraction, Fourier transform infrared (FT-IR), scanning electron microscope (SEM) and UV-visible spectroscopy. The release of caffeate anions from ZBS-CA and ZBS-CA/Ch is pH-dependent and is explained by a pseudo-second order kinetics model, with a linear correlation coefficient of R2 ≥ 0.99 at pH 4.8 and 7.4. The in vivo pharmacological assays showed excellent anti-edematogenic and antioxidant action of the ZBS-CA/Ch nanoparticle with slowly releases of caffeate anions in the tissue, leading to a prolongation of CA-induced anti-edematogenic and anti-inflammatory activities, as well as improving its inhibition or sequestration antioxidant action toward reactive species. Overall, this study highlighted the importance of ZBS-CA/Ch as an optimal drug carrier.

Abstract Purpose Early stage Merkel cell carcinoma (MCC) is a rare and aggressive primary skin cancer. The standard of care for MCC is broad excision and adjuvant external beam radiation therapy (EBRT). However, for some patients, anesthesia is contraindicated, while others run the risk of serious aesthetic sequelae. In such cases, exclusive radiotherapy is an interesting alternative to surgery. Though limited data is available, this study evaluates exclusive radiotherapy for MCC, using data from the largest retrospective study to date. Methods All patients who were followed in our center between 1989 and 2019 for histologically proven early stage MCC were included in the study. They were treated either by surgery with a 2-cm clear margin followed by adjuvant radiotherapy (RT) or by exclusive RT. Survival rates with adjuvant and exclusive EBRT were analyzed using Cox model and Fine and Gray model depending on the type of survival. p value

With the goal of developing refractory pastes to replace metal alloys used in turbine blades for Deep Space exploration, the French Space Agency, CNES, in collaboration with the Institute of Research for Ceramics, IRCER, has developed a preliminary research where dense alumina ceramics were formulated, printed and tested. This preliminary research will be the prelude to substituting by materials with more interesting creep properties at high temperature, for example, yttrium aluminum garnet, YAG. Since alumina is less expensive than YAG, preliminary tests were performed with alumina. These alumina pastes were 3D-printed by robocasting from very high solid loaded alumina pastes (>75 wt%), in the presence of organic additives, namely glycerol, PVA and ISOBAM 104. Several formulations of pastes were prepared, with the aim to obtain dense ceramic pieces. After, the alumina and the organic additives were mechanically mixed and the pastes were extruded with a commercial 3D printer. The best sample was obtained with a paste presenting an Al2O3 solid load of 79.37 wt% (63.5 vol%). A debinding step was performed afterwards to eliminate their organic content and the consolidation of the shaped pieces was finally achieved by sintering at 1700 °C. A % shrinkage of 8, 6.8 and 13.8 in the X, Y and Z-axes was measured, being one of the lowest values at 1700 °C compared to those in the literature.

Condensed tannins play a major role in the quality of red wine. After grape extraction, they quickly evolve thanks to different oxidation mechanisms. Recently, NMR identified a new sub class of condensed tannins, named crown procyanidins, in red wine. The crown procyanidins’ tetramer exhibits a macrocyclic structure composed of four (-)-epicatechin with an unusual cavity in the center of the molecule. These new tannins exposed a higher polarity than the linear tannins. In this work, the evolution kinetics of these crown procyanidins during the winemaking process and after aging of red wine in bottles were studied. Samples’ quantification was analyzed by UPLC-UV-Q-TOF. The concentration of cyclic and non-cyclic procyanidins was compared. During the winemaking process, crown procyanidins are mainly extracted at the beginning of the alcoholic fermentation and they remain stable until the end of the winemaking process. The high polarity and solubility of this new molecule in water was confirmed. During the aging of red wine in bottles, crown procyanidins’ concentrations are stable, whereas the non-cyclic tannins decrease dramatically. Finally, a strong oxygenation experiment confirmed the crown procyanidins’ resistance to oxidation and unique skills.

Superhydrophobic surfaces dramatically reduce skin friction of overlying liquid flows. These surfaces are complex and numerical simulations usually rely on models to reduce this complexity. One of the simplest consists of finding an equivalent boundary condition through a homogenisation procedure, which in the case of channel flow over oriented riblets, leads to the presence of a small spanwise component in the homogenised base flow velocity. This work aims at investigating the influence of such a three-dimensionality of the base flow on stability and transition in a channel with walls covered by oriented riblets. Linear stability for this base flow is investigated: a new instability region, linked to cross-flow effects, is observed. Tollmien-Schlichting waves are also retrieved but the most unstable are three-dimensional. Transient growth is also affected as oblique streaks with non-zero streamwise wavenumber become the most amplified perturbations. When transition is induced by Tollmien-Schlichting waves, after an initial exponential growth regime, streaky structures with large spanwise wavenumber rapidly arise. Modal mechanisms appear to play a leading role in the development of these structures and a secondary stability analysis is performed to retrieve successfully some of their characteristics. The second scenario, initiated with cross-flow vortices, displays a strong influence of nonlinearities. The flow develops into large quasi-spanwise-invariant structures before breaking down to turbulence. Secondary stability on the saturated cross-flow vortices sheds light on this stage of transition. In both cases, cross-flow effects dominate the flow dynamics, suggesting the need to consider the anisotropicity of the wall condition when modelling superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]