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Wood-polymer composites are increasingly produced through fused deposition modeling (FDM)—an additive manufacturing technique. The versatility of this technology has attracted several industries to print complex shapes and structures. This underscores the importance of studying the mechanical properties of the FDM parts, specifically, their elastic properties. A numerical homogenization methodology is introduced in the present study, focusing on the fundamental aspect of the elastic properties. Investigations were carried out on the influence of various parameters like wood volume fraction, aspect ratio, and internal porosity. The numerical results were validated using analytical models and experimental data. The comparison showed a satisfactory agreement with experimental data, where the relative error did not exceed 10%, leading to a strong conclusion about the validity and effectiveness of the proposed approach.

Since December 2019, the coronavirus disease (COVID-19) pandemic has catapulted the world into a marked health crisis, with over 29 million cases and >930,000 deaths. To better detect affected individuals at an early stage and stop disease progression to an advanced stage, several studies have been conducted to identify the clinical, biological, and radiological characteristics of COVID-19. This study aimed to enrich the literature by critically analyzing the clinical and biological characteristics of 134 patients from the North African Mediterranean region, including numerous genetic, epigenetic, and environmental factors that may influence disease evolution. This single-center retrospective study included all patients older than 18 years confirmed to have COVID-19 and hospitalized at the Cheikh Khalifa University Hospital affiliated with Mohammed VI University of Health Sciences, Casablanca, Morocco. Clinical, demographic, and biological data were analyzed in a cohort of severe and non-severe patients. Univariate analysis was performed to identify factors predictive of severity. There were 134 patients: the median age was 53 years, and 54.5% were male. Of these, 89 had mild to moderate disease; 45 had severe to critical disease, of which 14 died and 31 survived. Advanced age, presence of comorbidities, male sex, and infection in ethnic or family groups were risk factors for progression to severe disease. The presence of abnormalities in the following parameters were strongly associated with progression to severe disease: white blood cells (WBC), neutrophils, lymphocytes, C-reactive protein (CRP), procalcitonin, D-dimers, lactate dehydrogenase (LDH), ferritin, creatinine, aspartate aminotransferase (ASAT), and alanine aminotransferase (ALAT) during both admission and hospitalization. Based on these results and an extensive literature review, we recommend that clinicians closely monitor the biological parameters identified herein and perform immunological and genetic studies.

Fused deposition modeling (FDM) is one of the most used additive manufacturing processes in the current time. Predicting the impact of different 3D printing parameters on the quality of printed parts is one of the critical challenges facing researchers. The present paper aims to examine the effect of three FDM process parameters, namely deposition velocity, extrusion temperature, and raster orientation on the bending strength, stiffness, and deflection at break of polylactic acid (PLA) parts using Taguchi design of experiment technique. The results indicate that the temperature has the highest impact on the mechanical properties of PLA specimens followed by the velocity and the orientation. The optimum composition offering the best mechanical behavior was determined. The optimal predicted response was 159.78 N, 39.92 N/mm, and 12.55 mm for the bending strength, bending stiffness, and deflection at break, respectively. The R2 obtained from analysis of variance (ANOVA) showed good agreement between the experimental results and those predicted using a regression model.

In this paper, a numerical investigation is carried out on mixed convection in a vertical vented rectangular enclosure filled with Al2O3-water nanofluid. The mixed convection effect is attained by heating the right wall by a constant hot temperature and cooling the cavity by an injected or sucked imposed flow. The effects of some pertinent parameters such as the Reynolds number, 100  Re  5000, the solid volume fraction of the nanoparticles, 0    0.1, and the aspect ratio of the cavity, 1  A  4, on flow and temperature patterns as well as on the heat transfer rate within the enclosure are presented for the two ventilation modes. For a value of the aspect ratio A = 2, the obtained results demonstrate that the increase of volume fraction of nanoparticles contributes to an enhancement of the heat transfer and to an increase of the mean temperature within the cavity. Also, it was revealed that the fluid suction mode yields the best heat transfer performance. In the case when A is varied from 1 to 4, it was obtained that the heat transfer enhancement, using nanofluids, is more pronounced at shallow enclosures than at tall ones.

Textile industry wastewaters contain high concentrations of organic matter, toxic substances and dyes and pigments, and are harmful to receiving environment. Activated sludge system at pilot scale with continuous feeding, was used for the treatment of a dyeing unit effluent. The results showed that treatment allows a removal rate of 40-56 % of chemical oxygen demand (COD), and 13 to 30 % of color. The adsorption on sludge appears to be the main process responsible for the color removal of wastewater generated by textile industry.

In this work, we worked on the removal of pollution discharges stabilized leachate produced by the landfill of the city of Mohammedia using the process of the biodegradation of organic pollutants in air continuously or discontinuously. In order to predict the efficiency of a biological treatment for this type of effluent while minimizing the cost of ventilation. Landfill leachates produced by fermentation of waste are considered as a dangerous source of pollution to the environment. These waters are loaded with highly toxic metal and organic pollutants. They are difficult to treat and constitute a pollutant element for their quantitative and qualitative aspect. Discharges used in this study are characterized by a charge rich of high organic pollution more or less biodegradable, and whose NTK often greatly exceeds 1 g.L-1. The physico-chemical characteristics of leachate showed that the organic mater is readily biodegradable since COD/BOD5 ratio varies between 4.8 and 7.4. The results of this study showed that the continuous ventilation discharge leachate has a removal efficiency of 48 % COD neighbor which remains close to that obtained with the discontinuous aeration (52 %). This is accompanied by a variation of pH and the quantity of sludge biodegradation. No differences were observed between the aeration continuous and discontinuous.

The present paper reports numerical results of mixed convection and surface radiation within a horizontal ventilated cavity heated from below and provided with an adiabatic thin partition on the heated surface. Air, a radiatively transparent medium, is considered to be the cooling fluid. The effect of the governing parameters, which are the Reynolds number, 200 Re 5000, the relative height of the baffle, 0 Hb 0.75, and the emissivity of the walls, 0 1, on the fluid flow and heat transfer characteristics is studied in detail. The maximum and mean temperatures, the ratio, QE/QL, of the heat quantities leaving the cavity through the exit, QE, and through the left vertical cold side, QL, are also presented versus the above controlling parameters.

In this paper is reported an analytical and numerical study on double-diffusive natural convection in a non-Newtonian power-law fluid confined in a shallow horizontal rectangular enclosure submitted to uniform heat and mass fluxes along its short vertical sides, while the horizontal ones are insulated and impermeable. Here, the cases of aiding and opposing thermal and solutal buoyancy forces of equal intensities are considered. In the first part of the work the full governing equations are solved and the effects of the power-law behavior index, n, and the generalized thermal Rayleigh number, RaT , are examined and analyzed. In the second part, an analytical solution, based on the parallel flow approximation valid in the case of a shallow cavity, is proposed and an excellent agreement of results between the two approaches is observed, which validates them mutually.

Les abcès froids de la paroi thoracique représentent une forme rare et inhabituelle de tuberculose extrapulmonaire. Sa fréquence est estimée à moins de 5% des tuberculoses ostéoarticulaires, évaluées elles-mêmes à 15% des tuberculoses extrapulmonaires. L'objectif de ce travail est de rapporter la prise en charge diagnostique et thérapeutique de cette localisation dans notre structure. Etude rétrospective portant sur 18 cas colligés au service des maladies respiratoires du centre hospitalier universitaire Ibn Rochd de Casablanca, sur une période de 13 ans. La moyenne d'âge était de 34 ans (21-57). Un antécédent de tuberculose traitée était relevé dans un cas. Le tableau clinique était révélé par l'apparition insidieuse d'une masse pariétale de taille, de consistance et de siège variables. A l'imagerie thoracique, l'abcès pariétal était associé à une lyse osseuse dans sept cas, une atteinte parenchymateuse et pleurale dans quatre cas chacune et des adénopathies médiastinales dans deux cas. La confirmation diagnostique était bactériologique et/ou histologique dans tous les cas. La sérologie du virus de l'immunodéficience humaineétait négative chez tous nos malades. L'évolution sous traitement antibacillaire couplé ou non à une résection chirurgicale était favorable chez tous nos malades. Malgré la fréquence de la tuberculose dans notre contexte, la localisation pariétale thoracique reste rare, survenant chez une population non immunodéprimée et non toxicomane, contrairement à ce qui est souvent rapporté dans la littérature. Les abcès froids tuberculeux représentent une forme rare de tuberculose extrapulmonaire dont l'évolution reste favorable sous traitement précoce et bien conduit.

L'inhalation d'un corps étranger (CE) est une urgence médicale courante dans tous les âges. Chez l'adulte, cet accident est beaucoup plus rare que chez l'enfant et survient le plus souvent sur des terrains prédisposés. L'objectif est d'évaluer l'approche diagnostique et thérapeutique de l'inhalation endobronchique d'un CE chez l'adulte. Nous rapportons une étude rétrospective réalisée sur une période de plus de 20 ans (entre Janvier 1994 et Mai 2014) concernant 51 cas de CE endobronchiques de l'adulte. Leur mode de révélation, leurs caractéristiques cliniques, radiologiques et évolutives, la nature de ces CE inhalés sont décrits. Il s'agissait de 8 hommes et 43 femmes dont l'âge moyen était de 28 ans. Un terrain prédisposant est noté dans 13 cas. Le syndrome de pénétration était le maitre symptôme révélateur, retrouvé dans 46 cas. Le siège du CE était bronchique droit dans 30 cas. L'extraction est réalisée par bronchoscopie souple dans 40 cas, rigide dans 3 cas et par chirurgie dans 4 cas. Quatre patientes ont rejeté spontanément le corps étranger. La nature du CE était variable mais restait largement dominée par les épingles à foulards. Nous insistons sur la rareté et la gravité potentielle de l'inhalation de CE qui reste dominée dans notre contexte culturel par l'épingle à foulard chez les jeunes filles. En dehors d'un syndrome de pénétration évident, le diagnostic est souvent difficile faisant recours à la bronchoscopie à la fois diagnostique et thérapeutique. Les mesures préventives restent le meilleur traitement.

Le pseudo-Meigs syndrome comprend une tumeur pelvienne bénigne (en dehors des fibrothécomes ovariens) ou maligne associée à des épanchements, pleural et ou péritonéal, qui disparaissent après l'exérèse tumorale. Nous rapportons l'observation d'une patiente âgée de 47 ans, qui présentait une pleurésie droite associée à une ascite et une tumeur ovarienne maligne. L'évolution après l'exérèse chirurgicale de la masse tumorale même en l'absence d'une chimiothérapie montrait une disparition des épanchements. Le pseudo-Meigs syndrome est rare. Il nécessite des biopsies pleurales et péritonéales négatives, et la disparition des épanchements après l'exérèse chirurgicale de la tumeur, avant toute chimiothérapie. Une telle distinction est importante aussi bien sur le plan thérapeutique que pronostique.