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The increasing popularity of additive manufacturing technologies in the prototyping and building industry requires the application of novel, improved composite materials. In this paper, we propose the use of a novel 3D printing cement-based composite material with natural, granulated cork, and additional reinforcement using a continuous polyethylene interlayer net combined with polypropylene fibre reinforcement. Our assessment of different physical and mechanical properties of the used materials during the 3D printing process and after curing verified the applicability of the new composite. The composite exhibited orthotropic properties, and the compressive toughness in the direction of layer stacking was lower than that perpendicular to it, by 29.8% without net reinforcement, 42.6% with net reinforcement, and 42.9% with net reinforcement and an additional freeze–thaw test. The use of the polymer net as a continuous reinforcement led to decreased compressive toughness, lowering it on average by 38.5% for the stacking direction and 23.8% perpendicular to the stacking direction. However, the net reinforcement additionally lowered slumping and elephant’s foot effects. Moreover, the net reinforcement added residual strength, which allowed for the continuous use of the composite material after the failure of the brittle material. Data obtained during the process can be used for further development and improvement of 3D-printable building materials.

Depuis les années 80, l’élaboration de couches minces de silice, SiO2 à partir d’orthosilicate de tétraéthyle ((Si(OC2H5)4, TEOS) par dépôt chimique en phase vapeur (CVD) a été largement étudiée pour répondre aux problématiques de la microélectronique. Récemment, l’élargissement de l’éventail d’applications pour les revêtements à base de SiO2 pour l’optique, l’agroalimentaire, le biomédical, l’emballage ou la séparation des gaz, induit une modification des cahiers des charges tant pour les matériaux que les procédés. Il est souvent mis en avant les besoins de : (a) réduire le budget thermique lors de l’élaboration, (b) éliminer la formation de poudres, induites par exemple par une réactivité élevée en présence d’ozone, (c) revêtir des structures complexes, ce qui diminue l’intérêt des procédés plasma. En réponse à ces besoins, cette étude s’intéresse à la structure de couches de SiO2 amorphe élaborées à partir de TEOS et oxygène à pression atmosphérique à des températures Td comprises entre 400°C et 550°C, et corrèle ces caractéristiques à leur résistance à l’abrasion chimique.

International audience; An apparent kinetic model for the chemical vapor deposition of SiO 2 from tetraethyl orthosilicate (TEOS) and O 2 was developed in a poorly investigated range of operating conditions, that is, at atmospheric pressure and between 350 and 500 C, based on literature survey and experimental results obtained in a hot wall tubular reactor. The kinetic model was implemented into the computational fluid dynamics code FLUENT and validated both in shape and value by comparison with experimental deposition rate profiles. It reveals that for the conditions tested, a possible mechanism of SiO 2 deposition involves two intermediate species formed from TEOS homogeneous decomposition, the first one being active from 300 C and the second one contributing to deposition for temperatures higher than 370 C. The calculated local profiles of gas flow, gas temperature, species mass fraction, and silica deposition rate indicate that the first intermediate species leads to marked film thickness gradients, the second one being more stable as producing uniform thicknesses.

Chemical vapor deposited SiO2 films from tetraethyl orthosilicate (TEOS) is a key enabling material in numerous applications. Among the several pathways for the CVD of SiO2 films from TEOS, the poorly investigated medium temperature process involving oxygen ensures a compromise between the high thermal load of the surface reaction of the TEOS pyrolysis process, and the strong activation of gas phase reactions in the ozone assisted decomposition of TEOS. It is a promising route towards conformal coverage of complex-in-shape structures, growth rate control, and appropriate physical & chemical properties of the coating. SiOx films are obtained from TEOS+O2 in a horizontal CVD reactor operating at atmospheric pressure between 350 and 500°C. FTIR operating under normal and 55° incidence angle is used for the investigation of the structure, namely density, strain, oxygen content and stoichiometry of the films, by probing vibrational modes in the 900-1300 cm-1 region with well-resolved TO-LO phonon splitting. Complementary density values obtained by ellipsometry allow estimating the porosity of the films. Their corrosion resistance is investigated by the P-Etch test through thickness loss and is correlated with their composition, porosity and density.

Following bariatric surgery, a proportion of patients have been observed to experience reflux, dysphagia, and/or odynophagia. The etiology of this constellation of symptoms has not been systematically studied to date. This case describes a 36-year-old female with severe esophageal dysmotility following LSG. Many treatments had been used over a course of 3 years, and while calcium channel blockers reversed the esophageal dysmotility seen on manometry, significant symptoms of dysphagia persisted. Subsequently, the patient underwent a gastric bypass, which seemed to partially relieve her symptoms. Her dysphagia was no longer considered to be associated with a structural cause but attributed to a “sleeve dysmotility syndrome.” Considering the difficulties with managing sleeve dysmotility syndrome, it is reasonable to consider the need for preoperative testing. The question is whether motility studies should be required for all patients planning to undergo a LSG to rule out preexisting esophageal dysmotility and whether conversion to gastric bypass is the preferred method for managing esophageal dysmotility after LSG.

Latinos are nationally overrepresented among the uninsured, and rural Latinos are shown to face a variety of barriers to accessing quality health care. The Latino community continues to grow in the rural Midwest, and diabetes is a pertinent disease for research in this demographic. Diabetes care encompasses processes of care provided by health care professionals and personal health behavior including self-management activities, both of which may mitigate complications. The present research project investigated the degree to which the study population receives the recommended diabetes care services and executes self-management activities vis-àvis access to care. A quantitative, cross-sectional survey yielded responses from 134 participants on socio-demographic, access to care, and diabetes-related questions. The study sample was predominantly foreign-born with low income and educational attainment. Participants with a community health clinic as the source of diabetes care and those in advanced disease progression were more likely to receive the appropriate care services. This study population demonstrated higher proportions of most individual services received when compared with a national sample of Latinos but still warrants significant improvement in the delivery of the recommended preventive and monitorial diabetes care services. Improvements are also needed in all four of the selfmanagement activities investigated.

Modern medical therapy is increasingly based on evidence. The evidence presented here is that budesonide (Entocort, Astra Pharma) 9 mg/day is superior to placebo and equivalent to systemically active glucocorticosteroids in achieving disease remission in patients with active Crohn's disease, and in prolonging the recurrence time of symptomatic disease. Budesonide causes less disturbance to adrenal function than prednisone or prednisolone and may cause fewer steroid-associated symptoms. Thus, budesonide is the safer, more effective steroid of choice to treat patients with Crohn's disease.