scispace - formally typeset
Search or ask a question

Showing papers by "Prashant Kumar published in 2019"


Journal ArticleDOI
TL;DR: It is concluded that urban vegetation can facilitate broad health benefits, but there is little empirical evidence linking these benefits to air pollution reduction by urban vegetation, and appreciable efforts are needed to establish the underlying policies, design and engineering guidelines governing its deployment.

209 citations


Journal ArticleDOI
TL;DR: In this article, a portable battery-operated experimental set-up was designed for measuring the pollutant concentrations for 30 full days over a field campaign period of three months, and the results showed that the combination of trees and hedges resulted in reduced pollutant concentration behind the GI.

105 citations


Journal ArticleDOI
TL;DR: The goal of this review paper is to analyse and present a classification scheme, key features, and elements for designing nature-based solutions (NBS) and mitigating the adverse impacts of HMHs in Europe.

70 citations


Journal ArticleDOI
01 Dec 2019
TL;DR: The need to acknowledge the airborne spread of COVID-19 inside built spaces under eased movement restrictions and the potential steps that can be taken to control it is discussed.
Abstract: The World Health Organization declared the infectious spread of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) an epidemic during its initial outbreak in Wuhan (China) and has since declared it a pandemic and, more recently, an endemic infection that may remain in our communities. A vaccine for COVID-19 is expected to take several months, meaning that the spread may continue in future, in the absence of the most effective measures of social distancing and self-isolation. While these measures have worked well under lockdowns, the potential of airborne transmission of COVID-19 under the eased restrictions has not been considered important enough. We discuss the need to acknowledge the airborne spread of COVID-19 inside built spaces under eased movement restrictions and the potential steps that can be taken to control it.

68 citations


Journal ArticleDOI
TL;DR: In this paper, the status of air pollution, especially PM2.5, in 21 cities of China, on the basis of their status, chemical characteristics, and regulations data collected from published literature.
Abstract: The ambient fine particulate matter is a considerable hazard to human health and the surrounding environment of the majority of Chinese cities. This article reviews the status of air pollution, especially PM2.5, in 21 cities of China, on the basis of their status, chemical characteristics, and regulations data collected from published literature. The observed results show Zhengzhou, Yulin, Jinan, Qingdao and Changchun as significantly polluted cities where the annual mean concentration of PM2.5 was noted to be greater than 120 µg m-3. However, some cities such as Xiamen, Hong Kong, Shenzhen, and Jinchang reported average annual PM2.5 concentrations less than 40 µg m-3. In general, the results of spatial distribution reported that the cities of the east, north and northeast China are highly polluted. According to the average mass of PM2.5 in maximum cities of China, the sum of sulfate, nitrate and ammonium (SNA) and organic matter (OM) contributed over 40% and 35%, respectively. The higher amount of SNA and OM in PM2.5 result from heavy traffic or vehicle emission and burning solid fuel utilized in most part of China. A proposed systemic approach to address the PM2.5 in China can improve the quality of ambient atmosphere.

67 citations


Journal ArticleDOI
TL;DR: It is concluded that the deposition schemes that represent GI impacts in detail are complex, resource-intensive, and involve an abundant volume of input data, and an appropriate handling of GI characteristics in dispersion models is necessary for understanding the mechanism of air pollutant concentrations simulation in presence of GI at different spatial scales.

57 citations


Journal ArticleDOI
TL;DR: Various methods used for HMR assessment and its management via potential nature-based solutions (NBS), which are actually lessons learnt from nature are discussed, to enhance its wider significance for sustainable living, building adaptations and resilience.

54 citations


Journal ArticleDOI
TL;DR: In this paper, a simple and novel method for improving the thermal performance of natural convection energy storage system is reported, which can improve the overall performance of the systems with natural convective extended surfaces and makes it suitable for numerous heat transfer applications.

45 citations


Journal ArticleDOI
TL;DR: It is shown that erroneous data can be detected in a fully automated way, and that point and contextual outlier detection methodologies can be applied to low-cost air pollution data and yield meaningful results.
Abstract: Air pollution is a major environmental health problem around the world, which needs to be monitored. In recent years, a new generation of low-cost air pollution sensors has emerged. Poor or unknown data quality, resulting from the intrinsic properties of the sensor as well as the lack of a consensus on data processing methodologies for these sensors, has, among other factors, prevented widespread adoption of these sensors. To contribute to the creation of this consensus, we reviewed the available methodologies for quality control, outlier detection and gap filling and applied two outlier detection methodologies and five gap filling methodologies to a case study (consisting of an 11-month long air quality data set from a low-cost sensor). We showed that erroneous data can be detected in a fully automated way, and that point and contextual outlier detection methodologies can be applied to low-cost air pollution data and yield meaningful results. The linear interpolation showed the best performance for gap filling for low-cost air pollution sensors. In conclusion, data cleaning procedures are important, and the presented methods can form part of a generalised data processing methodology for low-cost air pollution sensors.

41 citations


Journal ArticleDOI
TL;DR: In this paper, the authors evaluated the long-term trends of PM10 at two monitoring stations (an urban and a background station) in Shimla city, in India during the period 2011-2017.

35 citations


Journal ArticleDOI
TL;DR: In this paper, a high-resolution, urban aerosol modeling framework has been developed to evaluate vertical variation of aerosol number concentration and size distribution in a simple street canyon without vegetation in Cambridge, UK.
Abstract: . Urban pedestrian-level air quality is a result of an interplay between turbulent dispersion conditions, background concentrations, and heterogeneous local emissions of air pollutants and their transformation processes. Still, the complexity of these interactions cannot be resolved by the commonly used air quality models. By embedding the sectional aerosol module SALSA2.0 into the large-eddy simulation model PALM, a novel, high-resolution, urban aerosol modelling framework has been developed. The first model evaluation study on the vertical variation of aerosol number concentration and size distribution in a simple street canyon without vegetation in Cambridge, UK, shows good agreement with measurements, with simulated values mainly within a factor of 2 of observations. Dispersion conditions and local emissions govern the pedestrian-level aerosol number concentrations. Out of different aerosol processes, dry deposition is shown to decrease the total number concentration by over 20 %, while condensation and dissolutional increase the total mass by over 10 %. Following the model development, the application of PALM can be extended to local- and neighbourhood-scale air pollution and aerosol studies that require a detailed solution of the ambient flow field.

Journal ArticleDOI
TL;DR: In this article, the authors compare concentrations of fine particulate matter (PM2.5) measured along a busy road section with ambient regional urban background levels, as measured at nearby regulatory air quality stations.
Abstract: Motivated by public interest, the Clean Air and Urban Landscapes (CAUL) hub deployed instrumentation to measure air quality at a roadside location in Sydney. The main aim was to compare concentrations of fine particulate matter (PM2.5) measured along a busy road section with ambient regional urban background levels, as measured at nearby regulatory air quality stations. The study also explored spatial and temporal variations in the observed PM2.5 concentrations. The chosen area was Randwick in Sydney, because it was also the subject area for an agent-based traffic model. Over a four-day campaign in February 2017, continuous measurements of PM2.5 were made along and around the main road. In addition, a traffic counting application was used to gather data for evaluation of the agent-based traffic model. The average hourly PM2.5 concentration was 13 µg/m3, which is approximately twice the concentrations at the nearby regulatory air quality network sites measured over the same period. Roadside concentrations of PM2.5 were about 50% higher in the morning rush-hour than the afternoon rush hour, and slightly lower (reductions of ˂30%) 50 m away from the main road, on cross-roads. The traffic model under-estimated vehicle numbers by about 4 fold, and failed to replicate the temporal variations in traffic flow, which we assume was due to an influx of traffic from outside the study region dominating traffic patterns. Our findings suggest that those working for long hours outdoors at busy roadside locations are at greater risk of suffering detrimental health effects associated with higher levels of exposure to PM2.5. Furthermore, the worse air quality in the morning rush hour means that, where possible, joggers and cyclists should avoid busy roads around these times.

Journal ArticleDOI
TL;DR: Diurnal and correlation analysis showed that traffic emissions and meteorological confounding factors were potential driving factors for changes in the PNCs (Dp ≤1 μm) at the modeling site, and probable local and transboundary inputs of P NCs in Kuala Lumpur.

Journal ArticleDOI
TL;DR: In this paper, a comparative assessment of cyclists' exposure to black carbon (BC) in three cities: London, Rotterdam and Sao Paulo, is presented, with an aim to understand the BC exposure variabilities while cycling during peak and off-peak hours, identify main pollution hotspots resulting in enhanced exposure and associate the measured concentrations with proximity to green areas and waterways.

Journal ArticleDOI
TL;DR: In this paper, the authors studied wind loads on a prototype, rectangular cross-section building, 80 m high, and found that across-wind direction governed the horizontal accelerations with wind targeted on the building's narrow face.

Journal ArticleDOI
TL;DR: The CBPF receptor model emerged as a reliable complementary tool for the identification of sources for considered gaseous pollutants that are less represented in the source apportionment studies and can be used for future scientific applications to assure more efficient air quality management.

Journal ArticleDOI
TL;DR: In this paper, the effect of varying particle size on viscoelastic properties of CoFe2O4 MNFs with varying CoFeO4 nanoparticle sizes was investigated.
Abstract: In this work, we have investigated the size induced on the viscoelasticity of CoFe2O4 magnetic nanofluids (MNFs). The focus of this work is to provide an insight into the effect of varying particle size on viscoelastic properties of CoFe2O4 MNFs with varying CoFe2O4 nanoparticle sizes. Kerosene-based MNFs containing surfactant coated CoFe2O4 were synthesized using standard optimized coprecipitation method, and variations in average mean size ~ 9–30 nm have been synthesized. The physical properties, such as structural and morphology, have been investigated to confirm the purity, and variation in size. Steady-state and oscillatory mode measurements were performed using a magneto-rheometer to investigate the field-induced magneto-rheology. The steady-state rheograms (viscosity vs. shear rate curve) has been well fitted with power-law $\eta =c\dot {\gamma }^{n}+\eta _{\infty }$ , confirming the shear thinning behavior with $n\le 1$ . Furthermore, magneto-sweep rheograms (viscosity vs. magnetic field) has been used to investigate the steady increase in viscosity, which is due to the formation of a chain-like structure in the field direction causing an interruption in the smooth streamline flow of the MNFs. Furthermore, dynamic oscillatory measurement shows the transition between G’ and G” with applied dynamic strain confirming solid-liquid phase transition behavior. Field-induced viscoelastic behavior in static and dynamic mode provides significant information for optimization of MNFs for various applications.

Journal ArticleDOI
TL;DR: In this paper, a detailed experimental investigation on the field dependent magneto-optical behavior of dilute water dispersed Fe3O4 based magnetic fluid was performed using nanoMOKE III.

Journal ArticleDOI
TL;DR: In this paper, a comparative assessment of various emission scenarios from highway and railway transportation between Kirsehir and Nigde-Ulukisla in the middle Anatolian Peninsula, in Turkey, to allow making an optimum decision from an environmental viewpoint was carried out.

Journal ArticleDOI
TL;DR: In this article, the authors assessed exposure concentrations of fine particles ≤ 2.5μm in diameter (PM2.5) and carbon monoxide (CO) inside bus, ac (air-conditioned) and non-ac car and on an Indian NH over 200 km length.

Journal ArticleDOI
TL;DR: In this paper, daily simulations of tropospheric carbon monoxide (CO) and ozone (O3) have been made using MOZART-4 (Model for OZone And Related chemical Tracers version 4) during 2007-08.

Journal ArticleDOI
TL;DR: These infections are more common in children and can lead to nutritional deficiencies, anemia, impaired learning, and growth retardation.
Abstract: One of the major health problems in developing countries like India is Intestinal Parasitic Infections (IPI’s). It is estimated that about 15-20% of world’s population is suffering from parasitic infection. Overall prevalence in India ranges from 12.5% to 66%. The prevalence of different parasitic infection varies from one place to another and depends on many factors such as socioeconomic status, hygiene, water supply, sanitation, population density, nutritional status and climatic conditions. 1 The transmission of parasitic infection takes place by ingestion, penetration of intact skin and rarely by inhalation of infective forms. 2 These infections are more common in children and can lead to nutritional deficiencies, anemia, impaired learning, and growth retardation. 1

DOI
01 Jan 2019
TL;DR: In this article, a guidance document summarises best practice regarding green infrastructure (GI) implementation for improved urban air quality and reduced pedestrian exposure to air pollution, and recommends recommendations for typical urban environments.
Abstract: Green infrastructure (GI) includes trees, hedges, individual shrubs, green walls, and green roofs. GI offers many different benefits or services, including flood risk mitigation, microclimate regulation, carbon sequestration, improved health and wellbeing and – the focus of this document – air pollution abatement. Air pollution comprises variable quantities of many different types of pollutants, including gaseous pollutants, such as nitrous oxides (NOx) and particulate matter (PM), which is composed of particles such as black carbon (BC). Road traffic is a dominant source of air pollution in urban areas globally. In near-road environments, vegetation can act as a barrier between traffic emissions and pedestrians (figure below), by collecting pollutants and/or redirecting the flow of polluted air. This document summarises best practice regarding GI implementation for improved urban air quality and reduced pedestrian exposure to air pollution. Generic (i.e. not site-specific) recommendations are offered for typical urban environments. These recommendations are based upon contemporary scientific evidence and knowledge, and may therefore be subject to modification as the evidence base develops. This guidance document consolidates major findings from relevant publications, including a detailed report on the relationship between vegetation and urban air quality, review articles and other guidance documents.

Journal ArticleDOI
TL;DR: The Evolthon community challenge as mentioned in this paper was organized to encourage creativity and cooperation in experimental evolution, where students and scientists from different labs were asked to evolve Escherichia coli or Saccharomyces cerevisiae for an abiotic stress-low temperature.
Abstract: In experimental evolution, scientists evolve organisms in the lab, typically by challenging them to new environmental conditions. How best to evolve a desired trait? Should the challenge be applied abruptly, gradually, periodically, sporadically? Should one apply chemical mutagenesis, and do strains with high innate mutation rate evolve faster? What are ideal population sizes of evolving populations? There are endless strategies, beyond those that can be exposed by individual labs. We therefore arranged a community challenge, Evolthon, in which students and scientists from different labs were asked to evolve Escherichia coli or Saccharomyces cerevisiae for an abiotic stress-low temperature. About 30 participants from around the world explored diverse environmental and genetic regimes of evolution. After a period of evolution in each lab, all strains of each species were competed with one another. In yeast, the most successful strategies were those that used mating, underscoring the importance of sex in evolution. In bacteria, the fittest strain used a strategy based on exploration of different mutation rates. Different strategies displayed variable levels of performance and stability across additional challenges and conditions. This study therefore uncovers principles of effective experimental evolutionary regimens and might prove useful also for biotechnological developments of new strains and for understanding natural strategies in evolutionary arms races between species. Evolthon constitutes a model for community-based scientific exploration that encourages creativity and cooperation.

Book ChapterDOI
01 Jan 2019
TL;DR: In this article, the authors provide an overview of wind energy and to appreciate the multidisciplinary nature of the engineering issues involved, including recent advances and challenges in design and construction.
Abstract: This chapter reviews the potential of wind as a sustainable power source. In particular, large-scale offshore wind farms have emerged as critical renewable energy technology to reduce GHG emission and autonomy in energy production. Each of these wind farms consists of many wind turbine generators, each mounted on a support structure and is capable of generating up to 1.2 GW of power. The aim of this chapter is to provide an overview of wind energy and to appreciate the multidisciplinary nature of the engineering issues involved. Recent advances are discussed and the challenges in design and construction are also highlighted.

Journal ArticleDOI
TL;DR: The accumulation of indoor pollutants in the hospital environment revealed the failure of hospital ventilation systems, and the design and implementation of an improved ventilation system in the studied hospital is recommended.
Abstract: The ambient air of hospitals contains a wide range of biological and chemical pollutants. Exposure to these indoor pollutants can be hazardous to the health of hospital staff. This study aims to evaluate the factors affecting indoor air quality and their effect on the respiratory health of staff members in a busy Iranian hospital. We surveyed 226 hospital staff as a case group and 222 office staff as a control group. All the subjects were asked to fill in a standard respiratory questionnaire. Pulmonary function parameters were simultaneously measured via a spirometry test. Environmental measurements of bio-aerosols, particulate matter, and volatile organic compounds in the hospital and offices were conducted. T-tests, chi-square tests, and multivariable logistic regressions were used to analyze the data. The concentration of selected air pollutants measured in the hospital wards was more than those in the administrative wards. Parameters of pulmonary functions were not statistically significant (p > 0.05) between the two groups. However, respiratory symptoms such as coughs, phlegm, phlegmatic coughs, and wheezing were more prevalent among the hospital staff. Laboratory staff members were more at risk of respiratory symptoms compared to other occupational groups in the hospital. The prevalence of sputum among nurses was significant, and the odds ratio for the presence of phlegm among nurses was 4.61 times greater than office staff (p = 0.002). The accumulation of indoor pollutants in the hospital environment revealed the failure of hospital ventilation systems. Hence, the design and implementation of an improved ventilation system in the studied hospital is recommended.

Journal ArticleDOI
TL;DR: Levobupivacaine is nearly equally effective to bupvacaine to produce sensory and motor blockade with comparable onset time and better haemodynamic stability with lesser side effects.
Abstract: Background: The present study was conducted to compare the effects of 0.5% isobaric levobupivacaine and 0.5% hyperbaric bupivacaine in pregnant females undergoing caesarean section. Methods: Study was conducted on 100 pregnant females undergoing caesarean section. They were randomly divided into two groups B and L receiving 2 ml of 0.5% hyperbaric bupivacaine and 0.5% levobupivacaine respectively. Two groups were compared with regard to sensory block, motor block, haemodynamic stability and complications if any. Results: Time to achieve sensory blockade till T6 dermatome was prolonged in group B (162.52±80.55 sec) as compared to group L (139.40±49.79 seconds) (p value= 0.087). Prolonged duration of motor blockade was observed in group B (160.76±6.56 minutes) as compared to group L (131.48±14.42 minutes) (p<0.001). Less haemodynamic stability was seen in patients of group B with more incidence of hypotension and bradycardia.as compared to group L. Conclusions: Levobupivacaine is nearly equally effective to bupivacaine to produce sensory and motor blockade with comparable onset time and better haemodynamic stability with lesser side effects.

Journal ArticleDOI
TL;DR: A methodological framework is provided and a computational algorithm that helps to identify soft changes in the travel behavior is described, based on a variety of different data sources such as activity-travel diaries and related constraint information, meteorological conditions, bicycle and public transport supply data, and emissions and air pollutant concentrations data.
Abstract: Informational interventions are important to bring positive changes in attitudes and perception among individuals. In relation to the individual’s mobility behavior, habits, attitudes, and perceptions are difficult to change. Therefore, it is vital to identify relatively soft aspects of travel behavior with a potential to reduce the negative impacts of mobility on the environment and individual health. This paper provides a methodological framework and describes the development of a computational algorithm that helps to identify soft changes in the travel behavior. The algorithm is based on a variety of different data sources such as activity-travel diaries and related constraint information, meteorological conditions, bicycle and public transport supply data, and emissions and air pollutant concentrations data. A variety of rules that are part of the algorithm are derived from the transport modeling literature, where constraints and factors were examined for activity-travel decisions. Three major aspects of activity-travel behavior, such as reduced car use, cold start of car engines, and participation in non-mandatory outdoor activities are considered in assessing pro-environmental potential. The algorithm is applied to collected small datasets from citizens of Hasselt (Belgium), Bologna (Italy), and Guildford (UK). A significant replaceable potential for car trips within 3 km to cycling and car trips to public transport has been found. The replaceable potential of excessive cold starts and participation in non-mandatory outdoor activities were also found, to some extent, to bring positive changes in the environment. In future research, these identified potentials are reported back to individuals with their consequence as part of a mobility-based informational intervention.

Book
10 Jul 2019
TL;DR: In this article, the effectiveness of DRASTIC model in a geographical setting for validation of vulnerable zones and presents the optimization of parameters for the development of precise maps highlighting several zones with varied contamination.
Abstract: This book shows the effectiveness of DRASTIC model in a geographical setting for validation of vulnerable zones and presents the optimization of parameters for the development of precise maps highlighting several zones with varied contamination. Impact of vadose zone has also been assessed by considering every sub-surface layer. Exclusive title covering effectiveness of DRASTIC model for groundwater vulnerability assessment Reviews of the strengths and limitations of assessment methods Presents multi-criteria evaluation of hydro-geological and anthropogenic factors Discusses integration with geographic information system (GIS) and remote sensing (RS) Includes application of groundwater governance framework with a case study study of a geographical setting

Journal ArticleDOI
TL;DR: In this article, the effect of annealing temperature and time on structural, microstructural, magnetic and magneto-optical properties of MnAl bilayer thin films was investigated.
Abstract: Ferromagnetism and magnetic anisotropy in Mn–Al thin films can be of great interest due to their applications in spintronic components and as rare-earth free magnets. Temperature-dependent uniaxial anisotropy has been observed in ferromagnetic MnAl thin films, which is attributed to the modification of the tetragonal lattice distortion with the change in annealing temperature, confirmed by VSM, MOKE and XRD results; the annealing time did not affect the magnetic anisotropy. A simple evaporation technique was used to deposit the Mn/Al bilayer thin films (thickness ∼ 64 nm) on GaAs substrates. A comprehensive study of the effect of annealing temperature as well as annealing time on structural, microstructural, magnetic and magneto-optical properties are reported in this paper. The ferromagnetic phase was enriched in annealed samples, which was confirmed by XRD, MOKE and magnetic hysteresis loops. XRD results revealed that the ferromagnetic τ-phase was enhanced in annealed films with the increase in annealing temperature ≥ 400 °C. Surface roughness was estimated from the AFM micrographs and was found to be increased, whereas the mean grain size was decreased on annealing the as-deposited Mn/Al bilayer thin film. The gradual increase in magnetic coercivity was found on increasing the annealing temperature. It is interesting to note that the magnetic easy axis can be tuned by changing the annealing temperature of MnAl thin films, and the easy axis changes from perpendicular to parallel direction of the film plane when the annealing temperature varies from 400 °C to 500 °C. MOKE results were also found to be consistent with the magnetic results.