In the present study, a total of five species of Vibrio bacteria were isolated from diseased shrimp, Litopenaeus vannamei, collected from commercial shrimp cultured ponds of Eethamukkala, Chinaganjam and Pedaganjam areas, Prakasam district, Andhra Pradesh. The isolated bacterial species were identified as Vibrio parahaemolyticus, Vibrio harveyi, Vibrio alginolyticus, Vibrio mimicus and Vibrio vulnificus. The symptoms shown by diseased shrimps include loss of appetite, red coloration of the body and pleopods, gills often appear red to brown in colour, reduced feeding, empty gut and general septicemia. In diseased shrimp, hepatopancrocytes may appear poorly vacuolated, indicating low lipid and glycogen reserve. In affected shrimps, localized lesions were also observed in the cuticle. Experimental infection trials reveals that V. parahaemolyticus is highly pathogenic to L. vannamei while V. harveyi found to be moderate pathogenic to challenged shrimp and remaining three bacterial species namely V.alginolyticus, V.mimicus and V.vulnificus were less pathogenic in nature.

The current work presents the design of automobile bumper using two novel materials, Flexible Polyurethane and Rigid Polyurethane, which meets the desired functional requirements for better performance. Two different designs for automobile bumpers have been made and corresponding deformation and stresses are investigated using Finite Element Analysis. The impact tests were carried out for two different materials of automobile bumpers. Scanning Electron Microscopy and Energy Dispersive Spectroscopy were done to characterize and compare the bumper materials with Rigid Polyurethane fabricated by Digital Light Synthesis. Both Flexible Polyurethane and Rigid Polyurethane outperform the existing bumper materials in terms of the impact strength. Among the new materials investigated, Rigid Polyurethane displays less deflection and Von-mises stresses and hence it may be suitable to replace the existing bumper materials in heavy vehicles with Rigid Polyurethane. The impact strength of Flexible Polyurethane is more than Rigid Polyurethane and hence this material may replace the existing materials in passenger cars.

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In vitro antibacterial activities of methanolic leaf and seed extracts of Moringa oleifera grown in Dodoma, Tanzania were evaluated using standard microdilution and disc diffusion methods against extended spectrum beta lactamase producing Gram negative bacteria (Escherichia coli and Klebsiella pneumoniae). Microdilution method showed no activity at concentration of 20 mg/mL for all the extracts except leaf extract which exhibited minimum inhibition at concentration of  2.5 µg/mL for E. Coli but when high concentrations of the extracts were used in the disc diffusion method then the results exhibited the highest killing susceptibility at concentration of 0.4 g/mL with zone of inhibition 31 mm for leaf extract and 26 mm for seed extract against E. coli, and 27 mm for leaf extract and 29 mm for seed extract against K. pneumonia. Additionally, when both extracts were screened qualitatively for phytoconstituents using standard methods, leaf extract confirmed the presence of carbohydrates, cardiac glycosides,  tannins and quinones, and seed extract confirmed the presence of proteins, carbohydrates, cardiac glycosides, alkaloids, terpenoids and quinones. These phytoconstituents can be new sources of future antibiotics that potentially combat the existing problem of antimicrobial resistance and thus, creating an awareness in the community regarding the usage of M. oleifera growing widely but neglected in Tanzania in spite of its nutritional values and traditional uses. Keywords: Moringa oleifera; Phytoconstituents; Antibacterial activity; Escherichia coli and Klebsiella pneumoniae

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