An environmental profile of brick kilns in Lucknow.

Twenty two kilns in Lucknow were studied to identify the environmental hazards posed by the brick kilns and to quantify the environmental degradation which could be attributed to this industry. Study variables comprised SPM and RSPM levels, metal concentrations and total silica content in soil, temperature, humidity and noise levels in the work environment. Information's about the nature and type of kiln, fuel and water sources was also collected. 18.18 per cent of the kilns had moving steel chimneys with less than prescribed height. Approximately 1.89 + 0.87 acre of fertile agricultural land was used for manufacturing of clay brick per kiln, resulting in land degradation decrease in herb density and nutrient disorders in plants/trees in immediate vicinity. SPM level (93.3 mg/m3) was found to be much higher than the prescribed limit. The workers engaged in these kilns were at risk from dust and heat related diseases.

Production of calcium gluconate by fermentation.

Calcium gluconate production by Aspergillus niger was investigated in shake flask, rolling shaker, air-lift reactor and stirred reactor. Growth pattern of the organism and fermentation conditions determined the yield of the product. High calcium gluconate production was achieved in air-lift reactor with pellet form of cell growth at moderate specific growth rate and biomass concentration. In another variation of air-lift reactor, when calcium carbonate was confined to a cellulose membrane, calcium gluconate production was maximum (149 g/L). At higher specific growth rate, obtained in shake flask, despite the formation of cell pellets, product formation was low. Physical separation of particulate calcium carbonate and growing cells favoured product formation. In stirred reactor pulpy mycelial growth was obtained and calcium gluconate production was poor.

Production of L-phenylacetylcarbinol by free and immobilized yeast cells.

Production of L-phenylacetylcarbinol (L-PAC) through biotransformation of benzaldehyde by free and immobilized cells of the yeast Saccharomyces cerevisiae has been attempted. L-PAC production was found to be maximum (0.4 microliter/ml) when anaerobically grown free cells were used as biocatalyst during aerobic biotransformation for two hours with magnetically stirred bioreactor. Growth under oxygen limited conditions led to accumulation of higher amount of pyruvate decarboxylase enzyme and co-substrate, pyruvate, resulting in higher L-PAC formation. L-PAC yield was low when biotransformations were carried out anaerobically either for aerobically or anaerobically grown free cells. Free cells were found to be more efficient biocatalyst for L-PAC production, as compared with the immobilized cells, with the investigated benzaldehyde concentration (0.3% v/v) and cell density (17.5% w/v). The study has explored and indicated the possibility of optimizing the yield of L-PAC by growing the yeast cells under oxygen limited condition for suitable aerobic mode of benzaldehyde biotransformation.

A carbon-limited medium for growth and sporulation of Bacillus thuringiensis var. kurstaki.

A culture medium for batch production of d-endotoxin by Bacillus thuringiensis (B., t.) has been modified. Through batch and continuous cultivation studies, the original medium was diagnosed to be limited in organic nitrogen. Corn steep liquor was found to be an excellent source for the organic nitrogen and its addition resulted in a carbon limited medium and in a significant increase in the amount of spore-toxin complex formed in shake flasks. Results of bioassay, conducted on Trichoplusia ni, suggest enhancement of larvicidal efficacy under carbon-limited growth conditions.

Occupational morbidity among children employed in brassware industry.

Fifty seven male children between ages of 10-16 years engaged in the brassware industry at Moradabad in Northern India were studied for occupational morbidity. The finding were compared with those obtained in the children (n = 29) engaged in other ancillary units which did not involve exposure to the metal fumes and dust in their work environment. The study showed a high prevalence of respiratory morbidity in the children engaged in the main units in comparison to those employed in the ancillary units (40.3 vs 27.6%; p less than 0.05). This was associated with significantly higher prevalence of pulmonary impairment in the former group (21.0%) particularly demonstrating restrictive ventilatory abnormality (10.5%) followed by bronchial obstruction (7.0%). The high respiratory morbidity may be attributed to chronic exposure to the fumes and dust of the metals such as nickel, chromium and cadmium. The children employed in the ancillary as well as in the main units showed high prevalences of musculo-skeletal disorders (27.6 and 22.8%) which may be caused by sustained faulty posture adopted during work and physical stress.

Ideal number of incisions in radial keratotomy--an experimental study.

The operation is very simple and safe and best for simple myopia. 16 ideal incisions give higher correction. Uniformity in depth of incision and steroid drops used post operatively brings higher correction.