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A leaf spring is a simple form of spring commonly used for the suspension system in heavy duty vehicles which is originally called laminated or carriage spring. It performs the isolation task in transferring the vibration due to road irregularities to the passenger's body or goods transported on it. The advantage of leaf spring over helical spring is that the ends of the spring have been guided along a definite path as it deflect to act as a structural member in addition to an energy absorbing device. Increasing competition and innovations in the automobile sector, tends to modify the existing products with new or advanced material products. To improve the performance of the suspension system, many modifications have been taken place overtime but the recent innovations imply parabolic leaf spring and application of composite materials, as the composite materials have high strength-to-weight ratio compared to the conventional steels. The present work attempts to analyze the comparison between the conventional steel (AISI1030) leaf spring and the composite (Carbon/Epoxy) leaf spring with respect to static and fatigue analysis. Here static analysis determines the safe stress, deformation and corresponding pay load and also studies the behavior of structures under practical conditions. The research also focuses on fatigue analysis to determine its life cycle and also to observe its fatigue failure characteristics. The model of the leaf spring has been carried out into the CAD software. The analysis of the steel leaf spring has been divided into theoretical, experimental and simulation sections. The simulation of steel leaf spring has been validated with the theoretical and the experimental results. Further simulation has been done for composite leaf spring by FEA software. Finally, the result shows that the composite leaf spring has better load carrying capacity in reduced weight, and better fatigue behavior rather than the conventional steel material for the leaf spring.

This prospective study was carried out in the coronary care unit, department of cardiology in National Institute of Cardiovascular Diseases, Dhaka, during the period of July 2007 to December 2007. Sixty consecutive patients with acute myocardial infarction below 40 years of age, subjected to coronary angiogram were enrolled with some inclusion and exclusion criteria to evaluate the risk factors and pattern of coronary artery disease in young patients with myocardial infraction. The age range of the study patients was 14-39 years with mean age of 29.07 ± 3.45 years. 56 (93.33%) patients were male and 4 (6.67%) patients were female. It was evident that commonest risk factor was smoking 73.33%. Other risk factors include dyslipidaemia 53.33%, hypertension 41.67%, hyperhomocystinaemia 25%, family history of IHD in 13.33% patients and diabetes 6.67%. Coronary artery diseases present in 91.67% patients. 72.73% patients had single vessel disease, 18.18% patients had double vessel disease and 9.09% patients had triple vessel disease. Left anterior descending artery involved in 80% patients, left circumflex artery involved in 27.27% patients and right coronary artery involved in 29.09% patients. In conclusion, acute myocardial infraction in young patients is most commonly seen in males and most frequent risk factor is smoking. Majority patients has single vessel disease and most frequently involve vessel is LAD.  University Heart Journal Vol.4(1) January 2008

This study was conducted at the Dhaka Medical College (DMC) morgue among 100 postmortem cases of Road Traffic Accident (RTA) victims over a period of one year. The objective of this study was to find out incidences of head injury among the RTA victims along with other injuries and also to overview the present situation of RTA in the country. Out of 100 cases, 64% were male and 36% female. The highest incidence of RTA (28%) was observed among the age group 31 to 40 years. The highest number of victims were pedestrians (68%). Considering recorded causality by type of collision, hit pedestrian was the most common (39%), followed by head on collision (20%). Regarding injury pattern in different parts of body, all the victims had multiple abrasion and bruise, 90% had laceration, 78% had injury to brain and 77% victims had injury to abdominal organs like liver and spleen. In the skull, Linear/fissured fracture was the commonest type of fracture (36%), followed by comminuted fracture (18%). Temporal bone was observed most prone to be fractured (23%), followed by parietal bone (17%). Most of the victims had subdural haemorrhage (43%), followed by sub arachnoid haemorrhage (36%). Key words: Road traffic accident, head injury, postmortem. DOI: 10.3329/jafmc.v5i2.4579 JAFMC Bangladesh Vol.5(2) (December) 2009, pp.24-28