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Aluminium 6082-T6 is a structural alloy having high strength has seen replacing 6061 alloy in engineering applications. During manufacturing process geometric discontinuities are inevitable. The presence of notch in the component is more dangerous. In this paper, the influence of notch length on miniature fracture characteristics of aluminium 6082-T6 alloy has been studied. Experiment was carried in accordance with ASTM standard and specimens were tested by varying the notch length within the specified constraint. Single edge notch bending test was performed on each of specimens under mode-I condition. Results showed that the specimen with minimum notch length has high crack tip initial instability, further increase in the notch length leads to decrease the load carrying capacity, extended portion of crack length and nature of fracture. On experimental observation, plastic zone size near the end of the cut is majorly dependent on notch length of the specimen. The fractured surface analysis also carried on selected specimen with the help of scanning electron microscope. Overall results shows that crack growth and crack propagation vary as a function of notch length and is different in each of the specimens.

The present study is aimed at detecting the association of autonomic dysfunction occurs in chronic severe anemia. All patients with hemoglobin less than 6 gm % and symptoms referable to anemia for > 6 months duration were included in the study. Patients with cardiac, hepatic, renal disease, leprosy, hypertension, diabetes mellitus and those on sympathomimetic, parasympatholytic, antihypertensive drugs and also patients below the age of 13 year were excluded from the study. Sample size is 50. RESULTS AND CONCLUSIONS: A total of fifty patients were included in the study. Among them, 20 (40%) were males and 30(60%) were females with male to female ratio of 1:1.5. majority of the patients were in the age group of 21-30years with mean age of 33 years. Dimorphic anemia was the most frequent type of anemia in 56% of cases: microcytic hypochromic anemia 42% and macrocytic seen only in 2%. Resting tachycardia of more than 100 per min was observed in 62% cases. Most of the cases (86%) had prolonged QTc interval of more than 0.40sec. 44% cases had abnormal valsalva response, 60% had abnormal 30/15 ratio, inspiration and expiration ratio was abnormal in 38% cases, and postural hypotension was observed in 86% cases. Diastolic raise in blood pressure to sustained hand grip was abnormal in 78% cases. Atropine test was abnormal in 26% cases. Two or more autonomic function tests were abnormal in all the cases. All the cases had combined sympathetic and parasympathetic involvement. 42% cases had involvement of afferent limb of parasympathetic reflex arc. The common abnormality found in cases of chronic severe anemia are postural hypotension and abnormal heart rate response to valsalva and standing are due to blunting of carotid body chemoreceptor and baroreceptor indicating of both sympathetic and parasympathetic involvement.

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