Improving Accuracy of Coarse Grid Numerical Solution of Solid-Solid Reactions by Taylor Series Expansion of the Reaction Term

Exothermic solid-solid reactions lead to sharp reaction fronts that cannot be captured by coarse spatial mesh size numerical simulations that are often required for large-scale simulations. We present a coarse-scale formulation with high accuracy by using a Taylor series expansion of the reaction term. Results show that such expansion could adequately maintain the accuracy of fine-scale behavior of a constant pattern reaction front while using a smaller number of numerical grid cells. Results for a one-dimensional solid-solid reacting system reveal reasonable computational time saving. The presented formulation improves our capabilities for conducting fast and accurate numerical simulations of industrial-scale solid-solid reactions

Fast convergence of dynamical ADMM via time scaling of damped inertial dynamics

In this paper, we propose in a Hilbertian setting a second-order time-continuous dynamic system with fast convergence guarantees to solve structured convex minimization problems with an affine constraint. The system is associated with the augmented Lagrangian formulation of the minimization problem. The corresponding dynamics brings into play three general time-varying parameters, each with specific properties, and which are respectively associated with viscous damping, extrapolation and temporal scaling. By appropriately adjusting these parameters, we develop a Lyapunov analysis which provides fast convergence properties of the values and of the feasibility gap. These results will naturally pave the way for developing corresponding accelerated ADMM algorithms, obtained by temporal discretization

Oral metronidazole as antibiotic prophylaxis for patients with nonperforated appendicitis

Hassan Ravari1, Ali Jangjoo2, Jalal Motamedifar2, Kasra Moazzami31Vascular and Endovascular Surgery Research Center, Imam Reza Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, 2Department of General Surgery, Mashhad University of Medical Sciences, Imam Reza Hospital, Mashhad, 3Department of General Surgery, Tehran University of Medical Sciences, Sina Hospital, Tehran, IranBackground: The rate of wound infection after appendectomy without antibiotic prophylaxis is 10%–30%. The role of prophylactic antibiotic therapy in nonperforated appendicitis is still controversial. Metronidazole is against anaerobic organisms and its bioavailability after oral and parenteral administration has been shown to be similar. The objective of the present study is to compare the infective complications rate after open appendectomy for nonperforated appendicitis receiving either oral or intravenous metronidazole as prophylaxis. Methods and Materials: From June 2007 to July 2009 in a randomized controlled trial, 204 patients with nonperforated appendicitis underwent an open appendectomy; 122 male and 82 female with mean age of 25 years. Among these, 102 (case group) received oral metronidazole and in 102 (control group) metronidazole was administered intravenously before surgery. The rate of wound infection and duration of the postoperative hospital stay was studied in the two groups.Results: The rate of wound infection was not significantly different in the two groups. (6% and 4% in study and control group, respectively, P = 0.861). Also the hospital stay was equal in two groups (2.3 days and 2.7 days in study and control group, respectively, P = 0.293).Conclusion: Single dose of oral metronidazole prior to operation can provide a sufficient prophylaxis for nonperforated appendicitis; so, it can be substitute the parental route of antibiotic administration. Keywords: antibiotic prophylaxis, wound infection, appendectomy, complication

UNE EXPLOITATION DU BIG DATA AU SERVICE DE LA RELATION ELECTEUR-POLITIQUE

La société contemporaine connaît une évolution rapide par rapport aux technologies de collecte, de traitement et de stockage de l’information. Ces évolutions génèrent des données toujours plus nombreuses, des traitements de plus en plus automatisés, complexes et rapides. L’exploitation de ces masses de données crée de nouvelles connaissances, de nouveaux services et de nouveaux comportements de la société. La terminologie utilisée pour décrire ces phénomènes est souvent « Big data ».Cet article expose de ce fait, une revue de littérature approfondie sur le système Big data, ainsi que son exploitation pour améliorer la relation électeur-politique. Le cas des élections présidentielles d’Obama est aussi mis en détail. Les processus d’analyse des données du Big data sont aussi présentés et une chaîne de valeur virtuelle pour l’exploitation du Big data pour créer de la valeur est proposée. 

Invention d’une Antenne Originale Micro-ruban Quadribande pour la Nouvelle Génération de la Téléphonie Mobile et l’Etude de l’Effet Thermique de GSM sur la Tête Humaine

La présente invention concerne une antenne micro-ruban quadribande imprimée originale miniature de forme carrée avec des fentes rectangulaires à faible coût, et dédiée à la nouvelle génération de la téléphonie mobile en couvrant  les bandes de fréquences 900MHz, 1800MHz, 2100MHz et 2600MHz. La modélisation et la simulation du modèle de base sont effectuées avec la méthode des éléments finis. Cette étude nous permettra de déterminer le coefficient de réflexion, le taux d’onde stationnaire (TOS), le rayonnement omnidirectionnel, le gain et la bande passante. Avec cette antenne, nous avons obtenu des nouveaux résultats de l’effet thermique de GSM sur  la tête humaine. Dans cet objectif, une nouvelle antenne carrée quadribande originale simple et miniaturisée en technologie microruban respectant les normes de la dosimétrie et la température destinée à des applications de la téléphonie mobile est conçue et proposée. Ce travail de recherche est déposé comme brevet d’invention national en décembre 2016 en collaboration avec l’université Mohammed V de Rabat

Application of Polyacrylamide for Methylene Blue Removal from Aqueous Solutions

In this study the removal of methylene blue (MB) dye from aqueous solutions by polyacrylamide (PAA) as a potential adsorbent was reported. PAA was characterized using SEM and FTIR measurements. Batch adsorption experiments were performed as a function of the solution pH, contact time, solute concentration and temperature. Evaluation of the obtained data with isotherm studies indicated that the adsorption process was matched well with the Langmuir model. The maximum capacity of adsorbent for MB was 111.1 mg g−1. Kinetic studies were carried out on various kinetic models and the pseudo-second order kinetic model was fitted very well with experimental data. Moreover, the thermodynamic parameters indicated that the adsorption reaction was endothermic and spontaneous process

Comparison of SARS-cov-2 RdRp protein with SARS-cov RdRp protein

The World Health Organization (WHO) declared, on January 30, 2020, a public health emergency of international scope because of the emergence of a new virus called SARS-cov-2. This new virus belongs to the coronavirus family and has a protein called RNA-dependent RNA polymerase (RdRp) which is responsible for the replication of viral RNA. RdRp protein is one of the most primary targets for antiviral drug discoveries. The aim of this paper was to compare the amino acid sequence of the RdRp of SARS-cov-2 with that of SARS-cov. Thus, we found that there is a 96% sequence similarity between them. Indeed, there is only a difference at the level of 32 amino acids. Interestingly, only one residue at C Motif and two residues at D Motif are different. However, all the residues of the motifs A, B, E, F and G are 100% identical with those of SARS-cov-RdRp