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Background: The development of antibiotic resistance in bacteria is a matter of global concern due to the exceptionally high morbidity and mortality rates. The outer membrane of most gram-negative bacteria acts as a highly efficient barrier and blocks the entry of the majority of antibiotics, making them ineffective. The Bam complex, β-barrel assembly machinery complex, contains five subunits (BamA, B, C, D, E), which plays a vital role in folding and inserting essential outer membrane proteins into the membrane, thus maintaining outer membrane integrity. BamA and BamD are essential subunits to fulfill this purpose. Therefore, targeting this complex to treat antibiotic resistance can be an incredibly effective approach. Natural bacterial pigments like violacein, phytochemicals like withanone, semasin, and several polyphenols have often been reported for their effective antibiotic, antioxidant, anti-inflammatory, antiviral, and anti-carcinogenic properties. Objective: Structural inhibition of the Bam complex by natural compounds can provide safe and effective treatment for antibiotic resistance by targeting outer membrane integrity. Methods: In-silico ADMET and molecular docking analysis was performed with ten natural compounds, namely violacein, withanone, sesamin, resveratrol, naringenin, quercetin, epicatechin, gallic acid, ellagic acid, and galangin, to analyse their inhibitory potential against the Bam complex. Results: Docking complexes of violacein gave high binding energies of -10.385 and -9.46 Kcal/mol at C and D subunits interface and at A subunits of the Bam complex, respectively. Conclusion: Henceforth, violacein can be an effective antibiotic against to date reported resistant gram-negative bacteria by inhibiting the Bam complex of their outer membrane. Therefore the urgent need for exhaustive research in this concern is highly demanded.

The quantification of bedrock river incision dynamics in tectonically active landscapes is an essential component of tectonic-geomorphology and hydrological studies. The channel incision is dependent on channel width. It is invariably observed in the field and in numerical models that the channel width varies with the spatial changes in tectonics, lithological, and climatic zones due to geomorphic forcing causing variability in rock uplift and erodibility. However, estimating channel width in the field and numerical modelling is tedious and often limited by terrain inaccessibility. We present an ArcGIS-based methodology to extract centerline and channel width using channel polygon extent derived from open-source high-resolution Google Earth images. The channel polygon boundary is used to extract a river centerline. The orthogonal line segment from the centerline is used to compute the river width continuously along the entire channel course in the ArcGIS platform, which is accurate in comparison to the other manual methods. We demonstrate the methodology on the Alaknanda and Bhagirathi rivers in Garhwal Himalaya, which has variable width along with different geological segments.

In this comprehensive review, an extensive analysis has been conducted on paleoclimate datasets from climatically sensitive regions in the Indian Himalaya and Indo-Gangetic plain. Our main objective was to gain valuable insights into the broad palaeoclimatic variability during the Late Quaternary-Holocene period. To achieve this, careful categorization was focused for various archives from multi-proxy studies into three groups: glacial moraine, glacio-fluvial and lake records, and speleothems. The compilation of climate records from different geographical settings has revealed an overall coherence during warm and humid phases, with minor variations influenced by variable moisture sources and topographic changes. The analysis reveals that Indian Summer Monsoon (ISM) reached its peak during approximately 9-5 ka BP and subsequently weakened around the Mid-Holocene (ca. 4–5 ka BP). Notably, the Last Glacial Maximum (LGM) and early Holocene were characterized by significant glacial advances in the Himalayan region. Furthermore, the sedimentation rates derived from lacustrine records in different regions exhibit considerable variability. In conclusion, the compilation and comparisons of diverse palaeoclimate records have significantly improved our understanding of the regions palaeoclimate. These findings hold substantial value for planning future focused studies in the crucial climatic zone. By refining our understanding of past climate dynamics in the Indian Himalaya and Indo-Gangetic alluvium, a better comprehension of the regions susceptibility to climate change can be achieved. This, in turn, facilitates informed decisions for sustainable development and environmental management.

The landscape, developed by the interaction of geological processes, is represented by Digital Elevation Models (DEMs) of various spatial resolutions. These DEMs can be variously analysed for the spatial and linear morphometric indices for landscape characterisation. We have developed MATLAB functions for extracting Hypsometric integral (Hi), Stream Length-gradient (SL) index, Normalized steepness index (ksn), Chi (χ) gradient index and Swath profile with maximum, minimum and mean elevation profiles from DEM. These functions are tested on SRTM DEM (30 ​m, 90 ​m spatial resolution) and ASTER GDEM (30 ​m spatial resolution) from three different catchments with varying tectono-geomorphic setup. The swath profile of the TRMM precipitation data is also prepared to demonstrate the application of present functions on different raster dataset and their robustness for multi-parametric correlations. The user-friendly MATLAB functions provide automation and flexibility to extract the morphometric indices cited above from DEM and other raster data with user defined variables for different tectonic-geomorphology and environmental studies.