Modelling of gaseous effluents by implementing Gaussian model under GIS environment.

In the present work, Gaussian based air quality model has been implemented under GIS environment for the air quality emission data obtained from IFFCO power plant at Phulpur, Allahabad, India. The application of corrections for the non-point source, obstacles on ground, surface roughness and observation time has made the Gaussian based air pollution model more accurate and flexible for its use and in its adaptation for any other location. The Gaussian based air pollution model for the IFFCO plant, implemented under GIS environment, has been tested for various validation points to check its efficacy and has been found to be suitable for prediction of air pollutants in future. Further, a user interactive modelling interface has been developed using Visual Basic as a front-end, implementing the ArcObjects of the ArcGIS 8.3 to make it more user-friendly and increase its acceptability among environmentalists, planners and decision makers.

Electrocardiographic changes in tetanus: a serial study.

Serial electrocardiograms (ECGs) were recorded in 20 consecutive male patients admitted to the Infectious Diseases Hospital, Calcutta with generalised tetanus. Age of patients varied from 5 to 40 years (mean age 20.4 years). Ten patients died. ECGs were recorded daily for the first week after admission and later every 2nd or 3rd day. Altogether, 167 ECGs were analysed. Sinus tachycardia was present in 17 (85%) patients, prolonged QT interval in 12 (60%) patients, non-specific ST-T abnormalities in 12 (60%) patients and P wave changes in 10 (50%) patients. Other abnormalities recorded, included short PR interval, supraventricular tachycardia, intraventricular conduction delay, sinus bradycardia, 1 degree A-V block, abnormal axis deviation, right ventricular hypertrophy and sino-atrial Wenckebach phenomenon, although all of the findings cannot clearly be attributed to tetanus. Spatial QRS-T angle was calculated in 18 of these patients to determine any possible change in this parameter of prognostic significance. Two out of 9 who survived had abnormally wide (greater than or equal to 55 degrees) spatial QRS-T angle on admission; the angle narrowed with recovery. In the non-survivor group, 4 patients had abnormally wide QRS-T angles on admission; further widening was noted in patients on whom follow-up tracings were available. The difference in spatial QRS-T angle between the survivor and the non-survivor groups was statistically significant (p less than 0.05). Spatial QRS-T angle changes have not been reported in tetanus before. Although non-specific, serial study in individual cases would be useful in assessing prognosis.