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In this work, the Galerkin–Vlasov method was used to solve the governing partial differential equation of equilibrium for isotropic sandwich plates with simply supported edges (x = ±a, y = ±b) and under uniform load on the plate domain Vlasov procedure was adopted in choosing the displacement shape functions as orthogonal eigen functions of dynamic Euler Bernoulli beams with equivalent spans, simple supports and loading as the plate. The resulting Galerkin-Vlasov equation was solved to obtain the unknown generalised shape function. It was found that the deflections obtained were exact solutions to the problem of bending isotropic sandwich plates. The deflection was found to be made up of two components: flexural deformation and shear deformation.

This study was carried using finite element software (Plaxis) in studying the Engineering behavior of erodible soil-quarry dust composite at a proportion of 50% quarry dust and 10% cement. It discusses the effects of decorative street light through numerical analysis using the Finite Elements Method. Plaxis program v8.2 was applied to model the soil behavior. The Mohr-Coulomb model reveals that the deformations are concentrated exclusively on the base course, with the appearance of plastic tension cut-off points on base course. The structure was subjected to double point loads of 50 kN/m each which resulted to 100 kN/m. The results shows that the pavement deformed at load 85.16kN/m which showed that the soil strength cannot withhold the pressure from the street light. The load displacement acting on the base of the highway in study is . The result also shows that failure was concentrated at the base course of the pavement. This was due to the presence of underground water beneath the phreatic level. The quarry dust is a good replacement to weak soil or a good additive to help improved a problematic soil. From analysis, the soil strength lies below the effective stress acting on the pavement which is equal to 85.16 kN/m. It is advisable to replace some quantities of the existing soil and be replaced by quarry dust since quarry dust is a waste product from crushing of stones. Lastly, about 30% of the existing soil should be replaced by either the mixture of lateritic soil and quarry dust or the soil there should be used as subbase which may not be economical.

Salmonella is considered to be one of the main pathogens causing human gastroenteritis worldwide. Looking for Salmonella in Africa in patients suffering from gastroenteritis is rather unusual, and the use of antibiotics is not subject to any regulation. This study intends for stressing the possible prominent importance of Salmonella in digestive diseases in Africa as well as identifying antimicrobial resistance of Salmonella isolates from faeces samples of human origin. All samples were collected from five N'Djamena hospitals, from patients suffering from diarrhoea. The collecting was undertaken over two periods of six months each: from August 2010 to January 2011 and from September 2011 to February 2012. Salmonella isolates were obtained by standard cultivation and serotyping methods. A total of 43 Salmonella isolates were identified, belonging to 21 different serovars. The most prevalent serovar was Salmonella Stanleyville (n = 7), followed by S. Anatum (n = 4) and S. Kottbus (n = 3). The other serovars were under-represented. The majority of these isolates were susceptible to all antibiotics tested (CLSI Standards), except two S. Enteritidis isolates that exhibited resistance to fluoroquinolones. The different serovars and antibiotic resistance profiles that were observed highlight the substantial diversity of Salmonella in N'Djamena, Chad. Roughly, one out of ten patients who consulted for gastroenteritis was shedding Salmonella spp. and none of them would have been diagnosed outside the context of this research program. This study may encourage local clinicians to explore more often salmonellosis suspicion in their daily practice.