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Biomedical subjects

M C Jain

Publications and source records attributed to M C Jain.

At least 19 recordsLinked to original sources

Methane emission from fixed dome biogas plants in hilly and plain regions of northern India.

Methane emissions from the slurry displacement chambers of different fixed dome type biogas plants (Capacity 2 m3) installed in hilly and plain regions of northern India were quantitatively estimated. The slurry temperature in the biogas plants in the hilly areas of Himachal Pradesh at an altitude of 1300 m above mean sea level remains below the lower mesophilic range (16-25 degrees C) during most part of the year. Difference in the ambient temperature under the two climatic conditions of Hills and plain regions affects the CH4 flux. Methane fluxes from the plants ranged between 7 and 120 gm(-2) d(-1). In northern plain, temperature remains warm (21-33 degrees C) throughout the year except during winter (December to January) when there is a steep fall. Seasonal emission of CH4 ranged between 10 and 178 gm(-2) d(-1). The annual average methane emission from the biogas plants in plain areas was 83.1 gm(-2) d(-1) as compared to 43.1 gm(-2) d(-1)in the hilly areas. Annual contribution per plant to the global methane budget from a fixed dome biogas plant (Cap 2 m3) in plain region of northern India was 53.2 kg as compared 22.3 kg in hilly area.

Bioelectric Energy Sources↗

Methane and nitrous oxide emissions from an irrigated rice of North India.

Upland rice was grown in the kharif season (June-September) under irrigated condition in New Delhi, India (28 degree 40'N and 77 degree 12'E) to monitor CH4 and N2O emission, as influenced by fertilizer urea, ammonium sulphate and potassium nitrate alone (at 120 kg ha-1) and mixed with dicyandiamide (DCD), added at 10% of applied N. The experimental soil was a typic ustochrept (Inceptisol), clay loam, in which rice (Oryza sativa L., var. Pusa-169, duration: 120-125 days) was grown and CH4 and N2O was monitored for 105 days by closed chamber method, starting from the 5 days and 1 day after transplanting, respectively. Methane fluxes had a considerable temporal variation (CV=52-77%) and ranged from 0.05 (ammonium sulphate) to 3.77 mg m-2 h-1 (urea). There was a significant increase in the CH4 emission on the application of fertilizers while addition of DCD with fertilizers reduced emissions. Total CH4 emission (105 days) ranged from 24.5 to 37.2 kg ha-1. Nitrous oxide fluxes were much lower than CH4 fluxes and had ranged from 0.18 to 100.5 g m-2 h-1 with very high temporal variation (CV=69-143%). Total seasonal N2O emission from different treatments ranged from 0.037 to 0.186 kg ha-1 which was a N loss of 0.10-0.12% of applied N. All the fertilizers significantly increased seasonal N2O emission while application of DCD reduced N2O emissions significantly in the range of 10-53%.

Air Pollutants↗

Soil properties and crop productivity as influenced by flyash incorporation in soil.

Field experiments were carried out during 1996-97 at Gulawathi, Muthiani and Salarpur Villages, IARI Farm, New Delhi and NCPP Campus, Dadri to evaluate changes in soil characteristics and growth of wheat (Triticum aestivum L.), mustard (Brassica juncea L.), lentil (Lence esculenta Moench.), rice (Oryza sativa L.) and maize (Zea mays L.) by varying amounts of flyash addition (up to 50t ha(-1)) in soils at sowing/transplanting time of crops. Flyash addition in areas adjoining NCPP Thermal Power Plant, Dadri, Ghaziabad, U.P. ranged from 5-12 t ha(-1)] yr(-1) in 1995-96. Shoot and root growth and yield of test crops at different locations after flyash incorporation resulted in beneficial effects of flyash addition in most cases. The silt dominant texture of flyash improved loamy sand to sandy loam textures of the surface soils at the farmers' fields. The increased growth in yield of crops with flyash incorporation was possibly due to modifications in soil moisture retention and transmission characteristics, bulk density, physico-chemical characters such as pH and EC and organic carbon content. The response of flyash addition in the soil on soil health and crop productivity needs to be evaluated on long-term sustainable aspects.

Agriculture↗

Effect of potassium salts and distillery effluent on carbon mineralization in soil.

Distillery effluent, a rich source of potassium, is used for irrigation at many places in the world. A laboratory experiment was conducted to study the influence of potassium salts present in post-methanation distillery effluent (PME) along with two other salts, KCl and K2SO4, on mineralization of carbon in soil. PME oxidized with H2O2, raw PME, KCl and K2SO4 solutions containing K equivalent to 10%, 20%, 40% and 100% of K present in PME were added to the soil separately, maintaining four replications for each treatment and control. Addition of salts up to a certain concentration stimulated C mineralization but a decline was noticed at higher concentrations. All the levels of salts caused higher CO2 evolution than the control suggesting that the presence of K salts enhanced the microbial activity resulting in increased CO2 evolution. The influence of K2SO4 was significantly higher than KCl in stimulating C mineralization in soil. Oxidized effluent had a higher stimulating effect than inorganic salts, showing the influence of other salts accompanying K in the PME. Raw PME, which contained excess organic C, increased CO2 evolution even at the highest salt level (100% PME) signifying the effect of added C on alleviating the salt stress on microbial activity.

Carbon↗

Emission of nitrous oxide from rice-wheat systems of Indo-Gangetic plains of India.

Nitrous oxide (N2O) accounts for 5% of the total enhanced greenhouse effect and responsible for the destruction of the stratospheric ozone. The rice-wheat cropping system occupying 26 million ha of productive land in Asia could be a major source of N2O as most of the fertilizer N in this region is consumed by this system. Emission of N2O as influenced by application of urea, urea plus farm yard manure (FYM), and urea plus dicyandiamide (DCD), a nitrification inhibitor, was studied in rice-wheat systems of Indo-Gangetic plains of India. Total emission of N2O-N from the rice-wheat systems varied between 654 g ha(-1) in unfertilized plots and 1,570 g ha(-1) in urea fertilized plots. Application of FYM and DCD reduced emission of N2O-N in rice. The magnitude of reduction was higher with DCD. In wheat also N2O-N emission was reduced by DCD. FYM applied in rice had no residual effect on N2O-N emission in wheat. In rice intermittent wetting and drying condition of soil resulted in higher N2O-N emission than that of saturated soil condition. Treatments with 5 irrigations gave higher emissions in wheat than those with 3 irrigations. In rice-wheat system, typical of a farmer's field in Indo-Gangetic plains, where 240 kg N is generally applied through urea, N2O-N emission is 1,570 g ha(-1) (0.38% of applied N) and application of FYM and DCD reduced it to 1,415 and 1,096 g ha(-1), respectively.

Air Pollutants↗

Methane production in rice soil is inhibited by cyanobacteria.

The present study was aimed at understanding the role of cyanobacteria and Azolla in methane production and oxidation in laboratory simulation experiments using soil samples from rice fields. All the seven cyanobacterial strains tested effected a significant decrease in the headspace concentration of methane in flooded soil, incubated under light. Synechocystis sp. was the most effective in retarding methane concentration by 10-20 fold over that in controls without cyanobacteria. The decrease in the headspace concentration of methane was negligible in nonsterile soil samples, inoculated with Synechocystis sp. and then incubated under dark. Moist soil cores (0-5 cm depth), collected from rice fields that had been treated with urea in combination with a cyanobacterial mixture, Azolla microphylla, or cyanobacterial mixture plus A. microphylla, effected distinctly more rapid decrease in the headspace concentration of methane added at 200 microl(-1) than did the soil cores from plots treated with urea alone (30, 60, 90 and 120 kg N ha(-1)), irrespective of the rate of chemical nitrogen applied to rice fields. Besides, soil cores from plots treated with urea alone at 60, 90 and 120 kg N ha(-1) oxidised methane more rapidly than did the core samples from plots treated with urea alone at 30kg N ha(-1). Cyanobacteria and A. microphylla, applied to flood water, appear to play a major role in mitigation of methane emission from rice fields-through enhanced methane oxidation.

Cyanobacteria↗

Increased biogas production using microbial stimulants.

Laboratory studies were undertaken to evaluate the effect of microbial stimulants Aquasan and Teresan, on biogas yields from cattle dung and combined residues of cattle dung and kitchen waste, respectively. The addition of single dose of Aquasan at the rate of 10, 15 and 20 ppm to cattle dung on the first day of incubation resulted in increased gas yields ranging between 45.1 and 62.1 l/kg dry matter. Subsequent addition of Aquasan at 15 and 20 ppm dosage after a period of 15 days increased the gas yields by 15-16%. The gas production was found to be optimum at a dosage level of 15 ppm and was 39% and 55% higher with single and dual additions, respectively, than untreated cattle dung. In another bench scale study (1:1 dry matter) the addition of Teresan at 10 ppm concentration to the mixed residues of cattle dung and kitchen wastes at different solids concentration, produced 34.8% more gas (272.4 l/kg d.m.) than the uninoculated mixture at 15% TS concentration (202.4 l/kg d.m.).

Anaerobiosis↗

Persistence of alpha and beta isomers of endosulphan and endosulphan sulphate in diverse soils of India as influenced by flooding.

Laboratory studies were undertaken to evaluate the persistence of alpha-endosulphan, beta-endosulphan and endosulphan sulphate in four diverse soils under non-flooded and flooded conditions. Significant variations were observed in the extent of persistence of the three chemicals in different non-flooded soils with maximum persistence observed in Alfisol and the least in Mollisol having near neutral pH and higher organic matter. Degradation was more in all the flooded soils than in the non-flooded counterpart but in Vertisol under flooded and non-flooded conditions, the rate of degradation of endosulphan sulphate was found to be nearly same.

Chemical Phenomena↗

Haemodynamic studies during the management of severe tetanus.

Detailed invasive haemodynamic studies were performed in 27 of 32 patients with severe tetanus. Nineteen had severe uncomplicated tetanus and eight had associated major complications, chiefly infection and pulmonary complications. The results were compared with those obtained from 15 healthy male volunteers who served as controls. There were two deaths in 32 patients (mortality 6.25 per cent). Severe tetanus without major complications was characterized by a high output hyperkinetic circulatory state with tachycardia (heart rate 131 (19.2) beats/minute), increased stroke volume index (43.1 (10.7) ml/m2), increased cardiac index (5.48 (0.94) l/min/m2) and a normal left ventricular stroke work index (60.5 (15.9) g/m/m2). Volume loading demonstrated a significant haemodynamic response and increased vascular capacitance. Even so the maximum percent rise from baseline values of these indices after volume load was significantly higher in controls (p < 0.001). Autonomic cardiovascular disturbances affected both sympathetic and parasympathetic activity. Hypertension and tachycardia alternating with hypotension and bradycardia were related to sudden fluctuations in systemic vascular resistance. Our studies suggested some degree of myocardial dysfunction in patients with severe uncomplicated tetanus. The haemodynamics of severe tetanus were masked and altered by complicating infection, pneumonia, and atelectasis.

Acute Disease↗

Biochemical studies into variation and repeatability of glutathione concentrations in bovine and bubaline semens.

Repeatability (r) value of glutathione (GSH) content was estimated in semen of Tharparkar, Red Dane, their crosses, and Murrah buffalo bulls. Mean GSH values were higher in bovine bull semen as compared to mean GSH values in bubaline bull semen. The r of GSH concentration for the pooled data was 0.1278. This trait is 12.78% repeatable. GSH value in semen of bovine and bubaline bull differed insignificantly. R estimates are expressed for selection of bulls of higher fertility and semen quality.

Animals↗

Piroximone (MDL 19,205) in the treatment of unstable and stable chronic cardiac failure.

The hemodynamic and clinical response to oral and intravenous piroximone was examined in 25 patients with chronic cardiac failure secondary to ischemic or myopathic heart disease: 14 with severe failure, who were clinically unstable (group I), and 11 with stable failure of mild to moderate severity (group II) in whom maximal O2 uptake (VO2 max) to treadmill exercise could be monitored serially. Intravenous (0.5 to 1.0 mg/kg) and oral (0.7 to 4.9 mg/kg) piroximone significantly (p less than 0.05) improved right and left ventricular pump function in both groups while causing an insignificant rise in heart rate and reduction in arterial pressure. Myocardial O2 uptake was not altered acutely or subacutely after piroximone, and myocardial lactate production was not observed. The salutary hemodynamic response to oral piroximone was sustained for 5 hours and there was no evidence of tolerance to the third and fourth doses. In group II, VO2 max was increased (p less than 0.05) at 4, 8, 12, 24, and 48 weeks of oral piroximone therapy. Adverse gastrointestinal effects were observed in two patients and a supraventricular tachycardia in another. Thus, piroximone may prove useful in the long-term management of chronic cardiac failure. Controlled clinical trials should be undertaken to determine the ultimate efficacy and safety of piroximone in these patients.

Administration, Oral↗

Newer positive inotropic agents in the treatment of chronic cardiac failure. Current status and future directions.

Heart failure is a serious worldwide health problem of major proportions. For many physicians, digitalis (an inotropic agent of limited proportions) and diuretics have proven the standard of treatment for heart failure. Vasodilators have also gained acceptance in recent years. Nevertheless, many patients remain symptomatic and therefore attention has been given to the development of pharmacological agents with mechanisms of action targeted to cardiac and vascular smooth muscle. The newer generation of inotropic agents have clearly been shown to improve the pumping function of the failing heart in patients who remain symptomatic despite digitalis, diuretics and vasodilators, while myocardial oxygen consumption is not enhanced. Several uncontrolled trials with the phosphodiesterase inhibitors enoximone, milrinone and piroximone have concluded that these agents improve exercise capacity and thereby hold promise to enhance quality of life. Large scale controlled trials currently in progress will determine the ultimate efficacy, as well as safety, of these agents. Results to date with several orally active beta-adrenoceptor agonists suggest that their efficacy may be limited by the induction of ventricular arrhythmias.

Animals↗