Design and optimization of a new compact 2.4 GHz-bandpass filter using DGS technique and U-shaped resonators for WLAN applications

The objective of this work is the study, the design and the optimization of an innovative structure of a network of coupled copper metal lines deposited on the upper surface of a R04003 type substrate of height 0.813 with a ground deformed by slots (DGS). This structure is designed in an optimal configuration for use in the design of narrowband bandpass filter for wireless communication systems (WLAN), the aim of use the defected ground structure is to remove the unwanted harmonics in the rejection band, the simulation results obtained from this structure using CST software show a very high selectivity of the designed filter, a very low level of losses (less than-0.45 dB) with a size overall size of 43.5x34.3 mm

Fracture energy of wood and root burl wood of thuya (Tetraclinis articulata (Vahl) Masters)

International audienceThe fracture energy of wood and root burl wood of thuya, coming from the forest of Essaouira (Morocco), was measured using a single edge notched specimen bending (SENB) test method. The variations along the longitudinal and transverse directions were studied using specimens taken from one radial section of thuya wood and on radial section of thuya burl, originating from two different trees. Thuya burl was more resistant than thuya wood to crack propagation in RL system (in the tangential plane). This difference is explained by the presence of dark growths, composed of cells with thicker walls that make the burl wood usually denser than thuya wood. Thuya burl was more resistant to crack propagation in RL system (tangential plane) than in TL system (radial plane), which is consistent with the radial orientation of the dark growths. The observed decrease of fracture energy along the longitudinal direction was explained by the progressive reduction of dark growth concentration

Contribution to the Optimization of the Radiation Performance of Patch Array Antenna for WiMAX Applications

The aim of this paper is to increase the operating distance of the WiMAX implementation by increasing the gain and the directivity using microstrip array antenna. We present the design of simple 2X2 microstrip array antenna operating at 5.38 GHz for WiMAX applications. The design is based on a single layer FR4 substrate, having a loss tangent o

Isolated radial volar dislocation of the fifth carpometacarpal joint :A rare injury

Isolated palmar dislocation of the fifth carpometacarpal joint is an uncommon injury and classified as radio-palmar or ulno-palmar according to the direction of displacement of the fifth metacarpal base . This very rare injury is often  difficult to recognize. A careful neurologic assessment of the patient is a  necessity, as well as obtaining proper radiographs of the hand. The purpose of this report is to present a patient with a pure isolated volar dislocation of the fifth carpometacarpal joint that was satisfactorily treated with closed  reduction and casting. A review of the literature is presente

Evidence of collaborative opportunities to ensure long-term sustainability in African farming

Farmers face the challenge of increasing production to feed a growing population and support livelihoods, whilst also improving the sustainability and resilience of cropping systems. Understanding the key factors that influence farming management practices is crucial for determining farmers’ adaptive capacity and willingness to engage in cooperative strategies. To that end, we investigated management practices that farmers adopt and the factors underlying farmers’ decision-making. We also aimed to identify the constraints that impede the adoption of strategies perceived to increase farming resilience and to explore how the acceleration of technology adoption through cooperation could ensure the long-term sustainability of farming. Surveys were distributed to farming stakeholders and professionals who worked across the contrasting environments of Morocco. We used descriptive statistics and analysis by log-linear modelling to predict the importance of factors influencing farmers’ decision- making. The results show that influencing factors tended to cluster around environmental pressures, crop characteristics and water availability with social drivers playing a lesser role. Subsidies were also found to be an important factor in decision-making. Farming stakeholders generally believed that collaborative networks are likely to facilitate the adoption of sustainable agricultural practices. We conclude that farmers need both eco- nomic incentives and technical support to enhance their adaptive capacity as this can lessen the socioeconomic vulnerability inherent in arid and semi-arid regions

Tuberculous Duodenal Stenosis: Report of Two Cases

Duodenal tuberculosis is a rare clinical entity. The authors report and emphasize the lack of special clinical, radiological and endoscopic signs of duodenal tuberculosis. The diagnosis is affirmed, at laparotomy, out of the findings of peritoneal granulations or histology of lymphatic nodes. We report our experience of two cases of duodenal tuberculosis presenting with proximal intestinal obstruction and review the available literature

Numerical Study of the Bond Strength Evolution of Corroded Reinforcement in Concrete in Pull‐Out Tests

The corrosion of rebars in reinforced concrete structures impacts their geometry (diameter and ribs) and mass, damages the concrete at the interface between the two materials, deteriorates the bond strength, and causes the cracking of the concrete cover. In the following study, a 2D numerical model of the pull‐out test is presented in order to study the impact of corrosion on the bond strength. Several parameters are investigated: the embedment depth, the rebar’s diameter, and the width of the concrete cover. The model reproduces the slip of the rebar and the failure through the splitting of concrete. It integrates an interface between the two materials and a concrete damage model that simulate the deterioration of concrete in compression and tension. The results obtained are validated with experimental data from the literature. Moreover, a parametric study is carried out to determine the impact of the embedment depth, the diameter of the rebar, and the concrete cover on the bond strength. The present study confirms that a greater embedment depth increases the pulling load. The study also confirms that the rebar’s diameter impacts highly the loss of bond between the rebar and the concrete cover. Lastly, the final main result of this paper is that the width of the concrete cover slows the loss of bond strength between the two materials

Application of mesenchymal stem cells in bone regenerative procedures in oral implantology. A literature review

Objective: The aim of this work was to review de literature about the role of mesenchymal stem cells in bone regenerative procedures in oral implantology, specifically, in the time require to promote bone regeneration. Study Desing: A bibliographic search was carried out in PUBMED with a combination of different key words. Animal and human studies that assessed histomorphometrically the influence of mesenchymal stem cells on bone regeneration procedures in oral implantology surgeries were examined. Reults: - Alveolar regeneration: Different controlled histomorphometric animal studies showed that bone regeneration is faster using stem cells seeded in scaffolds than using scaffolds or platelet rich plasma alone. Human studies revealed that stem cells increase bone regeneration. - Maxillary sinus lift: Controlled studies in animals and in humans showed higher bone regeneration applying stem cells compared with controls. - Periimplantary bone regeneration and alveolar distraction: Studies in animals showed higher regeneration when stem cells are used. In humans, no evidence of applying mesenchymal stem cells in these regeneration procedures was found. Conclusion: Stem cells may promote bone regeneration and be useful in bone regenerative procedures in oral implantology, but no firm conclusions can be drawn from the rather limited clinical studies so far performed

Péritonite primitive: entité réelle mais de diagnostic difficile

Les péritonites primitives sont rares chez des patients sans facteurs de risques. Elles simulent les péritonites secondaires. C’est pourquoi leurdiagnostic ne peut être que peropératoire. Nous rapportons deux cas de péritonites primitives dans le but de discuter leurs aspects diagnostique etthérapeutiques.Key words: Diagnostic, péritonite primitive, traitemen

Comparative Biology and Life Cycle of The Barley Stem Gall Midge and Hessian fly (Diptera: Cecidomyiidae) in Morocco

The barley stem gall midge, Mayetiola hordei (Keiffer) is the most serious pest of barley in Morocco. The biology and life cycle of this insect were studied in a laboratory and under natural weather conditions. The results showed that similarly to Hessian fly, barley stem gall midge has two feeding instars and a third non-feeding instar. The generation time was longer for barley stem gall midge than for Hessian fly (45 vs 32 days at 18 ± 1°C, and a 12:12 (L: D) h photoperiod). The eggs of barley stem gall midge hatched in 7 days compared to 4 days for Hessian fly. The largest discrepancy in developmental time was for second instar and pupa. Second instars and pupae of barley stem gall midge required twice as long as those of Hessian fly to develop and molt into next stage (12 vs. 6 days). The first and third instars of barley stem gall midge also required a little bit longer to complete development (9 and 10 days vs. 7 and 8 days for Hessian fly). Like for Hessian fly, barley stem gall midge reproduces mostly by unisexual progenies. Four progeny classes were observed; unisexual female progenies, unisexual male progenies, predominantly female progenies, and predominantly male progenies. The proportion of unisexual female and male progenies and the proportion of predominantly female and predominantly male progenies were similar. Overall, the sex ratio of both species was about 1:1. Under field weather conditions that prevail in the Chaouia region of Morocco, barley stem gall midge has two complete generations and a third partial one. The first generation starts late October, and ends late December. The second generation develops from January until early March. A high proportion of third instars of this generation fail to pupate (35%). The third generation is only partial; adults of the second generation emerge during March, oviposit and larvae develop to third instars but all go into summer diapause.