40 research outputs found
Numerical modeling of the face reinforcement of Djebel El-Kantour tunnel face (highway east-west)
The extension of communication ways (roads, highways, railways) often involves difficult crossings that usually lead to the construction of important structures such as tunnels. Similarly congestion on ground surface in cities necessitates the construction of underground structures (roads and metros). Terrain stability during construction especially in the coalface is one of the major problems related to the construction of these structures. This paper presents numerical modeling of the mechanical behavior of the rock face of the DJebel El-Kantour tunnel (East West Highway) reinforced by fits. In order to minimize on maximum the cost of numerical simulations, the reliability of three methods of homogenization of reinforced soil (improving cohesion, improving the cohesion and angle of friction and ultimately improve the Young's modulus) is tested by comparing the results of numerical simulations to the displacements measured insitu.Résumé :L’extension des voies de communication (routes, autoroutes, voies ferrées) impose souvent des franchissements difficiles qui conduisent généralement à la construction d’ouvrages importants tel que les tunnels. De même l’encombrement de la surface de sol dans les villes rend nécessaire la construction d’ouvrages souterrains (voiries et métros). La stabilité du terrain pendant les travaux notamment au front de taille est l’un des problèmes majeurs liés à la construction de ces ouvrages. Cet article présente la modélisation numérique du comportement mécanique du front de taille du tunnel Djebel El-Kantour (Autoroute est ouest) renforcé par des fits. Dans le but de minimiser au maximum le cout des simulations numériques, la fiabilité de trois méthodes d’homogénéisation des sols renforcés (amélioration de la cohésion, amélioration de la cohésion et l’angle de frottement et en fin amélioration du module de Young) sera testée, en comparant les résultats des simulations numériques aux mesures des déplacements insitu.Mots clés : Renforcement, sol, homogénéisation, tunnel, déplacement
NeobiÄŤna pristunost juvenilnih primjeraka vrste Synagrops japonicus u jugozapadnom Mediteranu
This paper reports additional records of the Indo-Pacific fish Synagrops japonicus (Doderlein, 1884) in Western Mediterranean. Twenty juveniles of this species ranging from 4 to 4.8 cm (TL) were caught in Annaba Bay, Algeria, using beach seine, in Summer of 2011 (9 specimens, 4 ≤ TL ≤ 4.6 cm) and 2012 (11 specimens, 4.2 ≤ TL ≤ 4.8 cm). Some hypotheses on the origin of this unusual
presence are discussed.U ovom radu se navode dodatni nalazi vrste Synagrops japonicus (Doderlein, 1884) u zapadnom Mediteranu. Uhvaćeno je dvadeset juvenilnih primjeraka ove vrste u rasponu od 4 do 4,8 cm
(TL) u Annaba zaljevu, Alžir, pomoću obalne mreže potegače, u ljeto 2011. godine (9 primjeraka, 4 ≤ TL ≤ 4,6 cm) i 2012. (11 primjeraka, 4.2 ≤ TL ≤ 4,8 cm). U radu su iznesene neke hipoteze o
podrijetlu ove neobiÄŤne prisutnosti
Numerical Analysis of the Crack Growth Path in the Cement of Hip Spacers
The use of temporary hip prosthesis made of orthopedic cement (spacer) in conjunction with antibiotics became a prevalent method used for prosthetic infections remedy; consequently, this method makes bone cement (PMMA) more fragile. Hence, the necessity of reinforcement incorporation is crucial to strengthen the bone cement. In this study, the finite element (FE) method was used to analyze the spacers behavior. FE model using an implicit integration method was used to simulate the mechanical behavior of the spacer under static loading. In addition, the extended finite element method (XFEM) was also used to investigate the fracture behavior of the non-reinforced and reinforced spacers. The results of this numerical analysis showed that the simulated crack initiation and propagation were in a good accordance with in vivo radiography and in vitro experimental observations. The full-stem reinforcement of 8 mm using reduce significantly the stress intensity factor and, consequently prevent the spacer fracture effectively. The FE models developed in this study contribute to help mechanical designers and engineers for prostheses’ quality and durability improvement.
Abstract must be 200 words maximum, without figures or refs.
 
Healed Lesions of Human Cutaneous Leishmaniasis Caused By Leishmania major Do Not Shelter Persistent Residual Parasites
In human cutaneous leishmaniasis (HCL) caused by Leishmania (L.) major, the cutaneous lesions heal spontaneously and induce a Th1-type immunity that confers solid protection against reinfection. The same holds true for the experimental leishmaniasis induced by L. major in C57BL/6 mice where residual parasites persist after spontaneous clinical cure and induce sustainable memory immune responses and resistance to reinfection. Whether residual parasites also persist in scars of cured HCL caused by L. major is still unknown. Cutaneous scars from 53 volunteers with healed HCL caused by L. major were biopsied and the tissue sample homogenates were analyzed for residual parasites by four methods: i) microscope detection of amastigotes, ii) parasite culture by inoculation on biphasic medium, iii) inoculation of tissue exctracts to the footpad of BALB/c mice, an inbred strain highly susceptible to L. major, and iv) amplification of parasite kDNA by a highly sensitive real-time PCR (RT-PCR). Our results show that the scars of healed lesions of HCL caused by L. major do not contain detectable residual parasites, suggesting that this form likely induces a sterile cure at least within the scars. This feature contrasts with other Leishmania species causing chronic, diffuse, or recidivating forms of leishmaniasis where parasites do persist in healed lesions. The possibility that alternative mechanisms to parasite persistence are needed to boost and maintain long-term immunity to L. major, should be taken into consideration in vaccine development against L. major infection
NeobiÄŤna pristunost juvenilnih primjeraka vrste Synagrops japonicus u jugozapadnom Mediteranu
This paper reports additional records of the Indo-Pacific fish Synagrops japonicus (Doderlein, 1884) in Western Mediterranean. Twenty juveniles of this species ranging from 4 to 4.8 cm (TL) were caught in Annaba Bay, Algeria, using beach seine, in Summer of 2011 (9 specimens, 4 ≤ TL ≤ 4.6 cm) and 2012 (11 specimens, 4.2 ≤ TL ≤ 4.8 cm). Some hypotheses on the origin of this unusual
presence are discussed.U ovom radu se navode dodatni nalazi vrste Synagrops japonicus (Doderlein, 1884) u zapadnom Mediteranu. Uhvaćeno je dvadeset juvenilnih primjeraka ove vrste u rasponu od 4 do 4,8 cm
(TL) u Annaba zaljevu, Alžir, pomoću obalne mreže potegače, u ljeto 2011. godine (9 primjeraka, 4 ≤ TL ≤ 4,6 cm) i 2012. (11 primjeraka, 4.2 ≤ TL ≤ 4,8 cm). U radu su iznesene neke hipoteze o
podrijetlu ove neobiÄŤne prisutnosti
Anti-oxidant and anti-acetylcholinesterase activities of Zygophyllum album
The present study was carried out to explore the anti-acetylcholinesterase activity and anti-oxidant effect as well as content of phenolic compounds of various extracts from Zygophyllum album. It was observed that dichloromethane and ethanol extracts were endowed with a powerful anti-acetylcholinesterase activity with IC50 values of 40 and 58 µg/mL, respectively. These two extracts exhibited the highest DPPH radical scavenging activity (IC50=0.2 mg/mL), the highest total anti-oxidant capacity (185.2 and 222.4 mg vitamin E/mg extract, respectively), the highest reducing power effect, and the highest ?-carotene bleaching capacity. The findings showed that the extents of anti-acetylcholinesterase activity of Z. album extracts as well as their anti-oxidant capacity are in accordance with their phenolic contents. Hence, Z. album leaves would be useful against Alzheimer's disease.
Video Clip of Methodology:
Determination of flavonoids content: 2 min 50 sec  Full Screen  Alternat
Réseau sur puce sans buffer pour les applications de codage vidéo : étude de cas H.264/AVC
Les réseaux sur puce ont émergé comme une solution d’interconnexion évolutive, flexible et réutilisable pour les applications des systèmes sur puce. Inspirés des réseaux informatiques, ils offrent un bon compromis entre le coût et la performance. Dans ce travail, nous présentons un réseau sur puce sans buffer pour les applications de codage vidéo. L’idée principale est d’utiliser un réseau sur puce sans buffer pour connecter les IPs composant l’encodeur vidéo H.264/AVC. L’architecture proposée est décrite en utilisant le langage de description matérielle sur une plateforme FPGA Virtex-7 XC7V2000T. Les résultats sont comparés à des travaux similaires utilisant d’autres solutions d’interconnexion et l’implémentation montre que l’architecture proposée offre une fréquence de fonctionnement maximale plus élevée avec une consommation en ressources logiques plus faible.Mots clés : Réseaux sur puce – systèmes sur puce – application de codage vidéo – encodeur H.264/AVC.Buffer-less Network-on-Chip for video encoding applications: case studyH.264/AVCNetworks on chip have emerged as new scalable, flexible and reusable On-Chip Interconnect solution for System-on-Chip applications. Inspired from computer networks, they offer a good compromise between cost and performance. In this work, we present a Buffer-less Network-on-Chip for video encoding applications. The main idea is to use a buffer-less NoC to interconnect the IPs composing the H.264/AVC video encoder. The proposed architecture is described using Hardware Description Language onto Virtex-7 XC7V2000T FPGA platform. Thereafter, results are compared to similar works using other interconnect solutions and the implementationshows that the proposed architecture offers a higher maximum frequency operating with a lower logic cost.Keywords: NoC, SoC, Video Encoder Application, H.264/AVC encoder.