Faculty Publications
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Item Characteristics of airborne bacteria in Mumbai urban environment(Elsevier, 2014) Gangamma, S.Components of biological origin constitute small but a significant proportion of the ambient airborne particulate matter (PM). However, their diversity and role in proinflammatory responses of PM are not well understood. The present study characterizes airborne bacterial species diversity in Mumbai City and elucidates the role of bacterial endotoxin in PM induced proinflammatory response in ex vivo. Airborne bacteria and endotoxin samples were collected during April-May 2010 in Mumbai using six stage microbial impactor and biosampler. The culturable bacterial species concentration was measured and factors influencing the composition were identified by principal component analysis (PCA). The biosampler samples were used to stimulate immune cells in whole blood assay. A total of 28 species belonging to 17 genera were identified. Gram positive and spore forming groups of bacteria dominated the airborne culturable bacterial concentration. The study indicated the dominance of spore forming and human or animal flora derived pathogenic/opportunistic bacteria in the ambient air environment. Pathogenic and opportunistic species of bacteria were also present in the samples. TNF-? induction by PM was reduced (35%) by polymyxin B pretreatment and this result was corroborated with the results of blocking endotoxin receptor cluster differentiation (CD14). The study highlights the importance of airborne biological particles and suggests need of further studies on biological characterization of ambient PM. © 2014 Elsevier B.V.Item Artificial neural network based modeling to evaluate methane yield from biogas in a laboratory-scale anaerobic bioreactor(Elsevier Ltd, 2016) Nair, V.V.; Dhar, H.; Kumar, S.; Thalla, A.K.; Mukherjee, S.; Wong, J.W.C.The performance of a laboratory-scale anaerobic bioreactor was investigated in the present study to determine methane (CH4) content in biogas yield from digestion of organic fraction of municipal solid waste (OFMSW). OFMSW consists of food waste, vegetable waste and yard trimming. An organic loading between 40 and 120 kg VS/m3 was applied in different runs of the bioreactor. The study was aimed to focus on the effects of various factors, such as pH, moisture content (MC), total volatile solids (TVS), volatile fatty acids (VFAs), and CH4 fraction on biogas production. OFMSW witnessed high CH4 yield as 346.65 L CH4/kg VS added. A target of 60–70% of CH4 fraction in biogas was set as an optimized condition. The experimental results were statistically optimized by application of ANN model using free forward back propagation in MATLAB environment. © 2016 Elsevier LtdItem The impact of spatiotemporal patterns of land use land cover and land surface temperature on an urban cool island: a case study of Bengaluru(Springer International Publishing, 2019) Govind, N.R.; Ramesh, H.In most of the developing countries, man-made developments in the environment have led to the growing demand to contextualize the land use land cover (LULC) changes and land surface temperature (LST) variations. Due to the modification in the surface properties of the cities, a difference in energy balance between the cities and its nonurban surroundings is observed. The aim of this study is to analyze the spatial and temporal patterns of LULC and LST and its interrelationship in Bengaluru urban district, India, during the period from 1989 to 2017 using remote sensing data. Intensity analysis was performed for the interval to analyze the LULC change and identify the driving forces. The impact of LULC change on LST was assessed using hot spot analysis (Getis–Ord Gi* statistics). The results of this study show that (a) dominant LULC change experienced is the increase in urban area (approximately 40%) and the rate of land use change was faster in the time period 1989–2001 than 2001–2017; (b) the major transition witnessed is from barren and agricultural land to urban; (c) over the period of 28 years, LST patterns for different land use classes exhibit an increasing trend with an overall increase of approximately 6 °C and the mean LST of urban area increased by about 8 °C; (d) LST pattern change can be effectively analyzed using hot spot analysis; and (e) as the urban expansion occurs, the cold spots have increased, and it is mainly clustered in the urban area. It confirms the presence of an urban cool island effect in Bengaluru urban district. The findings of this work can be used as a scientific basis for the sustainable development and land use planning of the region in the future. © 2019, Springer Nature Switzerland AG.Item Emission from open burning of municipal solid waste in India(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2019) Kumari, K.; Kumar, S.; Rajagopal, V.; Khare, A.; Kumar, R.Open burning of Municipal Solid Waste (MSW) is a potential non-point source of emission, which causes greater concern especially in developing countries such as India. Lack of awareness about environmental impact of open burning, and ignorance of the fact, i.e. ‘Open burning is a source of emission of carcinogenic substances’ are major hindrances towards an appropriate municipal solid waste management system in India. The paper highlights the open burning of MSW practices in India, and the current and projected emission of 10 major pollutants (dioxin, furans, particulate matter, carbon monoxide, sulphur oxides, nitrogen oxides, benzene, toluene, ethyl benzene and 1-hexene) emitted due to the open burning of MSW. Waste to Energy potential of MSW was also estimated adopting effective biological and thermal techniques. Statistical techniques were applied to analyse the data and current and projected emission of various pollutants were estimated. Data pertaining to population, MSW generation and its collection efficiency were compiled for 29 States and 7 Union Territories. Thereafter, emission of 10 pollutants was measured following methodology prescribed in Intergovernmental Panel on Climate Change guideline for National Greenhouse Gas Inventories, 2006. The study revealed that people living in Metropolitan cities are more affected by emissions from open burning. © 2017, © 2017 Informa UK Limited, trading as Taylor & Francis Group.Item Life cycle assessment of municipal solid waste management options for India(Elsevier Ltd, 2019) Khandelwal, H.; Thalla, A.K.; Kumar, S.; Kumar, R.Life Cycle Assessment (LCA) tool can be used for environmental assessment of Municipal Solid Waste Management (MSWM) system. The present study aims to evaluate the impact of MSWM system in Nagpur city, India under four different scenarios. i.e., composting combined with landfilling (S1), material recovery facility (MRF) & composting combined with landfilling (S2), MRF & anaerobic digestion (AD) combined with landfilling (S3) and MRF, AD & composting combined with landfilling (S4) using LCA tool. The sensitivity analysis was also performed for evaluating the influence of recycling rate of valuable resources in all the considered scenarios. The scenarios were compared using Gabi 8.5.0.79 model and CML-1A impact characterization method. S2 was found to have the least environmental impacts on global warming, human toxicity, eutrophication, and photochemical ozone creation potential categories. The sensitivity analysis indicated an inversely proportional relation between change in recycling rate and total environmental burdens. © 2019 Elsevier LtdItem Exploring the relationship between LST and land cover of Bengaluru by concentric ring approach(Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2020) Govind, N.R.; Ramesh, H.The present study aims at investigating the impact of land cover features in enhancing or mitigating Land Surface Temperature (LST) in a semi-arid tropical metropolitan city of Bengaluru, India. Spatial distribution of LST and land cover types of the area were examined in the circumferential direction, and the contribution of land cover classes on LST was studied over 28 years. Urban growth and LST were modelled using Landsat and MODIS data for the years 1989, 2001, 2005 and 2017 based on the concentric ring approach. The study provides an efficient methodology for modelling and parameterisation of LST and urban growth by fitting an inverse S-curve into urban density (UD) and mean LST data. In addition, multiple linear regression models which could effectively predict the LST distribution based on land cover types were developed for both day and night time. Based on the analysis of remotely sensed data for LST, it is observed that over the years, urban core area has increased circumferentially from 5 to 10 km, and the urban growth has spread towards outskirts beyond 15 km from the city centre. As urban expansion occurs, the area under the study experiences an expansive cooling effect during day time; at night, an expansive heating effect is experienced in accordance with the growth in UD in the suburban area and outskirts. The regression models that were developed have relatively high accuracy with R2 value of more than 0.94 and could explain the relationship between LST and land cover types. The study also revealed that there exists a negative correlation between urban, vegetation, water body and LST during day time while a positive correlation is observed during night. Thus, this study could assist urban planners and policymakers in understanding the scientific basis for urban heating effect and predict LST for the future development for implementing green infrastructure. The proposed methodology could be applied to other urban areas for quantifying the distribution of LST and different land cover types and their interrelationships. © 2020, Springer Nature Switzerland AG.Item An empirical investigation to understand mobile phone users’ behavioural intention to give their end-of-life mobile phones for formal recycling(Elsevier Ltd, 2024) Prabhu N, S.; Majhi, R.Mobile phones have turned into a highly essential device for numerous individuals. Swift innovation and decrease in in-use lifespan have increased the generation of end-of-life mobile phones (EOL-MPs). Lesser formal recycling of EOL-MPs has detrimental outcomes on the environment, human health, and circular economy. Therefore, this research was undertaken to investigate factors impacting mobile phone users’ behavioural intention to give their EOL-MPs for formal recycling. The conceptual model was developed by integrating the theory of planned behaviour, norm activation model, and value-belief-norm theory. Responses were collected from mobile phone users aged 18 and above residing in Bengaluru, Mangaluru, and Huballi-Dharvad cities of Karnataka state, India. 1135 responses were analysed by applying partial least squares structural equation modelling. Incentives was figured out to be the most positively impacting construct on behavioural intention. Followed by awareness of consequences, social media, past recycling experience, and recycling attitude. Whereas risk perception regarding information security and convenience of recycling negatively impacts behavioural intention. Personal norms get activated by awareness of consequences and ascription of responsibility. As a result, personal norms positively impact behavioural intention. In addition, biospheric values also positively impact personal norms. The outcomes of PLSpredict signify that the conceptual model has high out-of-sample predictive power. The outcomes of this research can be utilized by various stakeholders like e-waste collection organisations, e-waste recycling organisations, mobile phone manufacturing companies, city corporations, educational institutions, etc for improving sustainable end-of-life management of EOL-MPs. © 2024 Elsevier LtdItem Economic and environmental benefits of cool pavements: a case study of Bhubaneswar city(Springer, 2025) Anupam, B.R.; Chandra Sahoo, U.C.; Vinoj, V.; Rath, P.The change of land use from natural lands to built-up areas is one of the key reasons for the urban heat island (UHI) effect, because of absorbance and storing of heat energy. Roads and streets cover a significant fraction of the urban fabric and are continuously exposed to solar radiation. This study examines the impact of pavement surface temperature on urban air temperature. Measurements were made across the Bhubaneswar city to capture the temperature and relative humidity along the major arterial roads. The study quantified the UHI effect and evaluated the benefits of cool pavements in reducing air temperature and improving energy efficiency. The study reveals a strong relation between pavement surface temperature and near-surface air temperature. It was found that up to 1.5 m above the pavement surface, the impact of pavement surface temperature on the air temperature is substantial. On a particularly hot summer day, the air temperature just above the pavement surface and at 1.5 m above the surface was observed to be higher than the surrounding ambient air temperature by up to 7.4 °C and 2 °C, respectively. Based on the measurements taken during this limited period, the peak UHI intensity in Bhubaneswar city was found to be ~ 1.9 °C, which is high, if the current developments of the city are taken into consideration. This study also indicates that significant economic and environmental benefits can be achieved with the adoption of cool pavement technologies. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.