Browsing by Author "Sharma Mona"

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Appraisal of radiative transfer model 6SV for atmospheric correction of multispectral satellite image towards land surface temperature retrieval
(Elsevier, 2022) Prashant K. Srivastava; Nishita Jaiswal; Swati Suman; Smrutisikha Mohanty; Sharma Mona
Land surface temperature (LST) is very important parameter for broad range of applications related to weather and climate, hydrology, etc. For LST, satellite could be a very promising solution, but need to be corrected especially for atmospheric noises present in bands such as in red and near-infrared (NIR) windows. The atmospheric noises occurred due to ozone, water vapor, and aerosols cause reduction in reflectance values of red and the NIR bands which makes the normalized difference vegetation index (NDVI) values smaller than their true value. NDVI considered as an important variable for emissivity estimation and any loss in reflectance causes error in LST retrieval. In this study, for atmospheric correction of satellite image, radiative transfer model 6SV (second simulation of satellite signal in the solar spectrum-vector) was used and then the corrected image was utilized for the LST retrieval using Landsat 8 satellite thermal and visible bands. Changes in the values are found in the atmospherically corrected images of NDVI, plant fraction, emissivity, and LST as compared to the atmospherically uncorrected images. Hence, the reported approach could be a better choice for retrieval of LST due to its robust nature. © 2023 Elsevier Ltd. All rights reserved.
Deciphering Toxic Pollutants Breakdown Potential in Microbial Community of Chumathang Hot Spring, Ladakh, India via Shotgun Metagenome Sequencing
(Springer, 2024) Neha Saini; Mohd Aamir; Zainul Abdeen Khan; Vinay Kumar Singh; Pankaj Sah; Sharma Mona
Persistent Organic Pollutants (POPs) have been in focus of research due to their massive contamination of environment and bio-accumulation. Bioremediation and high-throughput research have gained momentum to curb the harmful effects of POPs. The present research has explored the microbial diversity of Chumathang Hot Spring, Ladakh, India, through Illumina metagenomic HiSeq 4000 sequencing platform and their potential to degrade persistent pollutants, especially xenobiotics. Taxonomic characterization based on raw metagenomic data illuminated the abundance of members of Pseudomonadota and Actinomyceota. The re-construction of the microbial genomes from assembled contigs and scaffolds using de novo assembler metaSPAdes and their further annotation through contig alignment with available reference genomes elucidated the landscape of the hot spring's microbes. The predominantly occupied key genera reported were Pannonibacter and Novosphingobium. Comparative genomic analysis established evolutionary relationships and functional diversities among hot spring microbial communities. The function annotation through MG-RAST has revealed their metabolic versatility of degrading a wide array of xenobiotic compounds, including caprolactam, dioxin, chlorobenzene, benzoate, and. Further, the hydroxylating dioxygenase (Saro_3901) was identified as a pivotal component in the aromatic degradation pathways, showcasing extensive metabolic interconnectivity. Interestingly, protein interaction network analysis identified hub genes like Saro_1233 (protocatechuate 4,5-dioxygenase alpha subunit), while Saro_3057 (amidase) was noted for its critical role in network communication and control. The resilience of thermal ecosystems, evidenced by robust enzymatic activity and degradation capability among organisms with < 95% genetic similarity, underscores their potential for industrial and bioremediation exploration, emphasizing the importance of preserving and studying biodiverse habitats. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.
Unveiling the microbial diversity and functional dynamics of Shiv Kund, Sohna hot spring, India through a shotgun metagenomics approach
(Springer Science and Business Media Deutschland GmbH, 2023) Neha Saini; Mohd Aamir; Vinay Kumar Singh; Bansal Deepak; Sharma Mona
In this research, we examined the microbial diversity in Sohna hot spring, Haryana, India using shotgun metagenome sequencing based on the Illumina Hiseq 4000 sequencing technology. The raw sequence data from metagenomic paired-end libraries were analysed for taxonomic classification, diversity, and functional annotation using MG-RAST online server. The results showed the presence of total of 57 phyla, 931 genera, and 2068 species, predominantly occupied by Moraxellaceae (Gammaproteobacteria). However, at the species level, we reported the presence of some representative pathogenic taxa, such as Acinetobacter baumannii and Moraxella osloensis. The functional annotation predicted at various levels based on SEED-based subsystem, KEGG ortholog identity (KO), Cluster of Orthologous Groups (COGs) database identified the predominance of genes associated with primary and secondary metabolism along with a crucial role in environmental and genetic signals, cellular communication, and cell signalling. Comparative Genome Analysis (CGA) using The Pathosystem Resource Integration Centre (PATRIC) tool based on genome annotation and assembly of the metagenomic libraries for representative taxon Acinetobacter baumannii (NCBI tax id:470) characterized the reads with a unique genome identifier of 470.20380 (A. baumannii DDLJ4) which is evolutionary closer to A. baumannii ATCC 470.17978 400667.7. In addition, the CARD database results about the presence of potential AMR pathotypes and the prevalence of adeABC, adeIJK, abeM gene-specific clusters that function as multidrug efflux pumps. Overall, the results provided a comprehensive insight into virulence and anti-microbial resistance mechanism and could be useful for developing potential drug targets against the possible AMR pathotypes. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.