Application of GIS in the study of mass transport of pollutants by Adyar and Cooum Rivers in Chennai, Tamilnadu

Residential, industrial, commercial, institutional and recreational activities discharge degradable and non-degradable wastes that reach the coastal water through rivers and cause coastal pollution. In the present study, mass transport of pollutants by Adyar and Cooum Rivers to the coastal water as a result of land-based discharges was estimated during low tide. The lowest and the highest flow recorded in Adyar varied from 514.59 to 2,585.08×10⁶ litres/day. Similarly, the flow in Cooum River fluctuated between 266.45 and 709.34×10⁶ litres/day. The present study revealed that the Adyar River transported 53.89–454.11 t/d of suspended solids, 0.06–19.64 t/d of ammonia, 15.95–123.24 t/d of nitrate and 0.4–17.86 t/d of phosphate, 0.004–0.09 kg/d of cadmium, 0.15–1.29 kg/d of lead and 3.03–17.58 kg/d of zinc to the coastal water owing to its high discharge. Similarly, the Cooum River transported 11.87–120.06 t/d of suspended solids, 0.08–58.7 t/d of ammonia, 6.11–29.25 t/d of nitrate and 0.66–10.73 t/d of phosphate, 0.003–0.021 kg/d of cadmium, 0.02–0.44 kg/d of lead and 1.36–3.87 kg/d of zinc. A higher concentration of suspended solids was noticed in post monsoon and summer months. An increase in the mass transport of ammonia, nitrate, phosphate in summer months (April and May) and an increase in the mass transport of cadmium, lead and zinc were observed in monsoon months (October–December) in both the rivers. Thus mass transport of pollutants study reveal that Cooum and Adyar Rivers in Chennai contribute to coastal pollution by transporting inorganic and trace metals significantly through land drainage.     

Genotoxic effects of two different classes of insecticide in developing chick embryos

Pesticides provide considerable protection against pest population; however, rampant accumulation of these chemicals into varied habitats across the globe necessitates the need for a careful screening of each chemical due to toxic manifestations. In the current study, the genotoxic potential of two different classes of commercial insecticides – chlorpyrifos and cypermethrin combination and Spinosad, a naturalyte were compared. Rhode Island Red chick embryos were exposed to different doses of either of these insecticides individually, by in ovo treatment. Genotoxicity was then evaluated through micronucleus (MN) test and Comet assay. The combination insecticide exposure at low doses of 0.05 and 0.1 μg/egg induced DNA damage as evidenced by an increased tail moment in the Comet assay. Further, the presence of micronucleated erythrocytes and also various abnormal cells including dacryocytes, microcytes, erythroplastids, squashed/notched nuclei, and spindle-shaped erythrocytes in the blood smear consolidates indicate the presence of insecticide-induced genotoxicity. Spinosad, however, was found only mildly genotoxic but at a high dose of 1.5 mg/egg. The results indicate that usage of naturalyte insecticide may be a better option to minimize the harmful effects of chemical insecticides.     

Evaluation of Extracted Chitosan from Portunus Pelagicus for the Preparation of Chitosan Alginate Blend Scaffolds

In recent years there is a growing need in generating a biocompatible and cost effective porous scaffold for tissue engineering purposes. Therefore, this study focused on conversion of the shell waste of locally available crab variety P.pelagicus (Blue swimming crab) into the chitosan scaffold. As the poor mechanical strength of chitosan limits its usage in tissue engineering, it was blended with alginate. The scaffolds were prepared by the freeze gelation method which requires less time and minimum energy, with fewer residual solvent and easier to scale up. To the best of our knowledge there are no reports on scaffold preparation from the extracted chitosan, blended with alginate by freeze gelation method. The biological properties of chitosan-alginate scaffolds (Cts–Alg) were evaluated and compared with those of chitosan scaffolds. The prepared scaffolds were characterized by SEM, swelling property, in vitro enzymatic degradation, and hemo, biocompatibility properties. Chitosan-alginate scaffolds had an average pore size of 40 μm and tensile strength of 0.564 ± 0.0.018 % MPa. Its swelling ratio was 27.5 ± 0.28 %, with mass loss percentage of 10 ± 0.33 % after 4 weeks of degradation. It has exhibited good hemocompatible properties too. Mouse fibroblast 3T3 cells were able to adhere and proliferate well in the blended scaffold. All these results indicated that chitosan-alginate scaffold is a suitable alternative substitute for tissue engineering.     

Altitude distribution of aerosols over Southeast Arabian Sea coast during pre-monsoon season: Elevated layers,long-range transport and atmospheric radiative heating

Every year, during the pre-monsoon period (March–May), a pronounced increase in aerosol optical depth (AOD) is observed over the eastern Arabian Sea, which is attributed to the transport of continental aerosols. This paper presents the altitude distribution of tropospheric aerosols, characteristics of elevated aerosol layers and aerosol radiative heating of the atmosphere during the pre-monsoon season over Trivandrum (8.5°N, 77°E), a station located at the southwest coast of Indian peninsula which is covered by the eastern Arabian Sea plume. Altitude profiles of aerosol backscatter coefficient (β_a) and linear depolarization ratio (LDR) reveal two distinct aerosol layers persisting between 0–2 km and 2–4 km. The layer at 2–4 km, which contributes about 25% of the AOD during polluted conditions, contains significant amount of non-spherical aerosols. This layer is prominent only when the advection of dry airmass occurs from the northern parts of the Indian subcontinent and northern Arabian Sea. Role of long-range transport in the development of this aerosol layer is further confirmed using latitude–altitude cross-section of β_a observed by CALIPSO. Aerosol content in the layer below 2 km is large when advection of air occurs from the north and east Arabian Sea and is significantly small when it occurs from the southwest Arabian Sea or Indian Ocean. During the highly polluted conditions, aerosols tend to increase the diurnal mean atmospheric radiative heating rate by ～0.8 K day^?1 at 500 m and 0.3 K day^?1 at 3 km, which are about 80% and 30% of the respective radiative heating in the aerosol-free atmosphere.     

Active pharmaceutical ingredient (api) from an estuarine fungus, Microdochium nivale (Fr.)

Various marine habitats sustain variety of bio-sources of ecological and biotech potentials. Pharmaceutical potential compound Cyclosporine A was reported from marine fungus Microdochium nivale associated with Porteresia coarctata, a marine salt marsh grass from mangrove environment distributed along the Central West Coast (CWC) of India. This study involves association of M. nivale with P. coarctata plant, fermentation conditions, purification of Cyclosporine A, chemical characterization etc. Its antifungal inhibition and MIC (Minimum inhibitory concentration) against Aspergillus strains (A. niger, A. japonicus, A. fresenii), yeasts and dermatophytes (Candida sp., Cryptococcus neoformans, Trichophyton mentagrophytes, T. tonsurans, T. violaceum, Microsporium gypsum and Fusarium sp.) were evaluated. However, the MIC against A. japonicus, C. neoformans, Candida sp. and T. tonsurans were confirmed to be as low as 12.5-25 mg disc(-1). The antifungal properties of Cyclosporine A against Aspergillus species, yeast and dermatophytes revealed that CyclosporineAwould be a potential compound for life threatening diseases caused by above fungi in both human and animals. Furthermore, we have reported herewith another source of Cyclosporin Aderived from filamentous fungus, M. nivale. occurring in marine environment.     

Experimenter instructions as a mediator in the effects of culture on mapping one's neighborhood

In study 1 children, aged 6 and 12 years from southern India and mid-west USA were asked to construct a map of the neighborhoods around their schools. Performance on map making was measured in three ways: (1) the number of features depicted; (2) cognitive maturity in map representation (using Piaget's stages) and (3) furthest point represented. Significant main effects for performance was found for cultural context. Indian children depicted more features than American children while American children had more coordinated maps and depicted features further away from their school.In the second experiment, a different sample of same aged children in the same region of the USA and India were given differing instructions about the purpose of the mapping task. It was found that children tailored their maps for the purpose for which they had to construct it. The cultural differences in Piagetian stages disappeared; Indian children continued to exhibit a more intimate knowledge of their neighborhoods while American children depicted landmarks further away.     

Biosynthesis of (S)-1-(1-naphthyl) ethanol by microbial ketoreductase

Environmental Science and Pollution Research - (S)-1-(1-naphthyl) ethanol (SNE) is a chiral drug intermediate for the production of mevinic acid analog, a potent cholesterol agent. It acts as an...     

Neem extract–blended nanocellulose derived from jackfruit peel for antibacterial packagings

Environmental Science and Pollution Research - The use of jackfruit peel as a source for natural and fully biodegradable “nanocellulose” (NC) for the production of bioplastics with...     

Input-export fluxes of heavy metals in the Cochin estuary,southwest coast of India

Cochin estuary (CE) is one of the largest tropical estuaries along the southwest coast of India, sustaining rich bio-resources. Several studies enlighten the environmental changes in the CE caused by anthropogenic activities. In the present study, an attempt has been made to quantify the heavy metal (dissolved and particulate) fluxes brought by the six rivers into the CE with their exchange into the coastal ocean through the major inlet at Cochin during a steady flow period (October–November 2015). The water flux across the inlet was quantified using an acoustic doppler current profiler. The measured daily input of dissolved metals from the rivers was 2.43?×?10³ kg Fe, 334 kg Zn, 259 kg Ni, and 83 kg Cr, while that of particulate metals were 85.30?×?10³ kg Fe, 8. 6?×?10³ kg Mn, 236.9 kg Cr, and 111.9 kg Zn. The net export of metals through the Cochin inlet (per tidal cycle) was 3.3?×?10³ kg Fe, 515 kg Cr, 150 kg Zn, and 5 kg Ni in dissolved form and 3.32?×?10⁵ kg Fe, 1747 kg Mn, 1636 kg Cr, 1397 kg Zn, and 586 kg Ni in particulate form. The high concentrations of metals during ebb tides are clear indications of their contribution from the industrial conglomerates (industrial units of metallurgy, catalyst, fertilizer, and pesticides) located in the Periyar River. The significance of this study is that the export fluxes may increase further during the summer monsoon (June to September), which may impact the abundant fishery emanating in the coastal environment during the period due to intense upwelling.