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Landfill gases are produced due to biodegradation of organic fraction of municipal solid waste (MSW) when water comes into contact with buried wastes under prevailing anaerobic conditions. To minimize the percolation of water in landfills, the conventional approaches such as clay capping is still practised in India. As landfill gas extraction system is an expensive technique,'Phytocapping' to mitigate landfill gases and to minimize percolation of water into the landfill can be one of the attractive alternatives. The present study aimed to determine efficiency of a laboratory-scale phytocap in terms of methane emissions, heavy metals' remediation and plant-soil interactions in Indian climatic conditions using six native plants in five planters (30 cm × 30 cm × 25 cm) with 5 kg of MSW. Overall methane oxidation due to vegetation was observed throughout the vegetated planters when compared to non-vegetated planters. Root zone methane concentrations were also monitored for the plant species, with the highest reduction occurring in root zones of Agave sisalana and Bambusa sulfurea and highest trace elements' remediation potential was observed in Brassica juncea and Helianthus annus plants. 96-98% of CH4 oxidation and 85-89% of heavy metals remediation was achieved through the study.

Phycoremediation ability of microalgae namely Oscillatoria acuminate and Phormidium irrigum were validated against the heavy metals from tannery effluent of Ranipet industrial area. The microalgae species were cultured in media containing tannery effluent in two different volumes and the parameters like specific growth rate, protein content and antioxidant enzyme activities were estimated. FTIR spectroscopy was carried out to know the sorption sites interaction. The antioxidant enzymes namely superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) contents were increased in microalgae species indicating the free radical scavenging mechanism under heavy metal stress. SOD activity was 0.502 and 0.378 units/gram fresh weight, CAT activity was 1.36 and 0.256 units/gram fresh weight, GSH activity was 1.286 and 1.232 units/gram fresh weight respectively in the effluent treated microalgae species. Bio sorption efficiency for Oscillatoria acuminate and Phormidium irrigum was 90% and 80% respectively. FTIR analysis revealed the interaction of microalgae species with chemical groups present in the tannery effluent. From the results, the microalgae Oscillatoria acuminate possess high antioxidant activity and bio sorption efficiency when compared to Phormidium irrigum and hence considered useful in treating heavy metals contaminated effluents.

Prominent microalgal species, namely Anabaena, Oscillatoria, Phormidium, and Spirogyra, were isolated from estuaries polluted with tannery effluents and studied to determine their Cr(VI) bio-sorption potential. The bio-sorption potential was determined by studying the effect of growth, biomass, reduction of Cr(VI) levels, and Cr(VI) absorption by the microalgal species. The respective values for Anabaena, Oscillatora, Phormidium, and Spirogyra compared with the control were as follows: growth in BG 11 medium containing tannery effluent was 53.99, 60.03, 55.76, and 55.85%; the biomass was 60.65, 77.61, 67.16, and 76.01%; the Cr(VI) reduction potential was 70.96, 80.64, 76.12, and 74.83%; and the bio-sorption potential was 75.48, 80.64, 79.35, and 77.41%. The removal of heavy metals by microalgal biomass involves bio-reduction and bio-sorption. Fourier-transform infrared spectroscopy and nuclear magnetic resonance results revealed the presence of microalgal sorption sites. All four species showed ma...

This letter reports a novel in vitro test of blood analysis based on the measurement of the dielectric properties at microwave frequencies. The measurements were made using rectangular cavity perturbation technique at the S-band of microwave frequency with the different samples of blood obtained from healthy donors as well as from patients. It is observed that an appreciably change in the dielectric properties of patient samples with the normal healthy samples and this measurements were in good agreement with clinical analysis. This measurement technique is nondestructive in nature. These results indicate an alternative in-vitro method of diagnosing blood abnormalities using microwaves.

The effect of the electromagnetic fields on the human brain due to the usage of mobile phones is an active research area. These effects are a direct function of the electrical properties of the brain tissue which depends on the bound water content. This paper reports the microwave study of cerebrospinal fluid (CSF), the main constituent of which is water. Both normal and pathologically abnormal CSF samples are subjected to the microwave study and a study of the variation of the dielectric parameters of CSF with frequency is done for both the normal and pathologically different samples. In this communication, in vitro measurements using cavity perturbation technique is employed. The frequency range employed is between 2 to 3 GHz. It is seen that in the band of frequencies employed for the study, the normal and abnormal CSF samples exhibit distinctive behavior for the variation of dielectric constant and conductivity with frequency.