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3D INTERNAL LAVA FLOW ARCHITECTURE OF DECCAN BASALTS WITH IMPLICATIONS FOR CARBON STORAGE
No full textThe research focuses on characterizing the basalt flows to evaluate their potential in CO2 storage, specifically underlining mineral trapping as a safe and long-term mechanism for trapping CO2. High divalent cation content in basalts is ideal, such as in the case of mafic and ultramafic lithologies like the Deccan basalts of Junglee Jaigad, Maharashtra, India. Outcrop analogue studies, like in the case of comprehensive photogrammetric analysis by drones, are quite informative when considering geological heterogeneities and pathways of CO2 migration. A DJI Mavic AIR2 drone captured 1403 images, which were processed into 3D models using Agisoft Metashape. Georeferenced models aligned with DEM data were finally used to outline lava flow boundaries, provide thickness, and give uncertainty estimates. Furthermore, variations in thickness along these lava flows were mapped using VRGS and GemPy. Surfer software was used for producing thickness maps. Thicknesses range from 10 m up to 35 m, and surface dips range from 0° to 4° NW. Lava flow units, which are of the simple pahoehoe type consists of vesicular crust and massive core, summarise the many aspects of the study's basalt flow features. They are crucial for assessing the storage capability and CO2 movement paths inside basalt formations
Investigating the impact of site-specific phosphorylation and acetylation on aggregation of N-terminal and NAC-derived alpha-synuclein peptides
No full textHydrology and water management in the Anthropocene: challenges and opportunities with particular reference to India
No full textThe Anthropocene period is characterised by multiple stressors triggered by human-induced changes in the hydrological cycle and land surface transformations. The arrival of humans on this planet has significantly altered the biophysical systems, particularly since the Industrial Revolution, commonly known as the era of the Great Acceleration. It is important to recognise these changes in the hydrological systems and start planning country-specific and sustainable strategies to mitigate the challenges posed in terms of water availability and demands, water-related disasters, river health and river ecology. It is of particular importance to realise that our water resource system may already cross the tipping point of exploitation. Water is undoubtedly the most essential commodity for humans, but it is equally important to understand the needs of other ecosystems that depend on water. This article documents the challenges and opportunities of water resource management in the Anthropocene, which is particularly relevant to India and proposes a series of urgent measures to mitigate the situation. We reason that a better understanding of our hydrological systems will contribute to water security and resilience to society in terms of water and the environment and contribute to the growth of the nation
Non-linear dynamical approaches for multi-sector climate resilience under irreducible uncertainty
No full textInternal climate variability (ICV) remains a major source of uncertainty in climate projections, complicating impact assessments across critical sectors. Given that ICV emerges from the nonlinear interactions of the climate system, we argue that nonlinear dynamical (NLD) approaches can improve its characterization, providing physically interpretable insights that strengthen adaptation strategies and support multisector decision-making. However, despite their suitability for such problems, NLD approaches remain largely underutilized in the analysis of initial condition large ensembles (LEs). We argue that a diverse suite of NLD approaches offers a promising pathway for systematically extracting robust insights from LEs. If effectively applied and systematically integrated, these methods could fully harness the potential of LEs, uncovering underlying patterns and variability across ensemble members to refine fundamental insights from climate projections. This will help bridge the gap between complex climate dynamics and practical resilience strategies, ensuring that decision-makers, resource managers, and infrastructure planners have a more reliable foundation for navigating irreducible uncertainty
Superior impact resistance conferred by hierarchical nacre-inspired nanocomposites: A molecular dynamics study
No full textInnovations in impact-resistant materials design inspired by nacre's hierarchical “brick and mortar” structure have ushered a new era of lightweight biomimetics with exceptional strength and toughness. However, the role of microstructure, notably the effect of hierarchy, is hitherto poorly understood. Here, we investigate the impact resistance of graphene-polyethylene nanocomposites that are modeled after nacre's microstructure, capturing the behavior of the stiff (graphene) and soft (polyethylene) phases. Besides the dependence of the impact resistance on the graphene grain size and grafting between the phases, we show that it is the hierarchy that plays the most important role in drastically enhancing impact resistance, with the hierarchical nanocomposite showing up to a three-fold improvement in the ballistic limit without grafting, and a seven-fold increase in the presence of grafting. This research also sheds light on the detailed molecular mechanisms behind these enhancements that can be leveraged for the development of advanced biomimetic materials
Sonochemical Exfoliation of AlB2 into Few-Layer-Thick Chemically Functionalized Borophene with Inherent Reducing Capability
No full textUltrasonication-assisted liquid-phase exfoliation of layered metal diborides has emerged as a promising path for obtaining metal-deficient quasi-2D nanostructures. In this study, we show that ultrasonication can be combined with chelation to achieve exfoliation of AlB2 in high yields. We show that ultrasonicating AlB2 crystals in a solution containing ethylenediaminetetraacetate results in nearly metal-free, few-layer-thick nanosheets rich in boron. These nanosheets exhibit crumpled morphology with several instances of crystalline regions. AFM indicates thickness values between 1 and 6 nm with lateral dimensions extending up to a few microns. Chemical analyses show ultra-low aluminum content (Al:B molar ratio as low as 0.04:2) and presence of oxy, hydroxy, and hydride functional groups, rendering these as chemically functionalized borophene (CFB) nanosheets. We found that the yield of nanosheets can be increased up to 30% by choosing an appropriate pH. We further show that these nanosheets exhibit an inherent reducing capability and can catalyze the reduction of gold salt into gold nanoparticles while simultaneously serving as templates to stabilize them, with the growth of nanoparticles up to 10 nm. This study lays the ground for top-down approaches to synthesize chemically functionalized borophene in high yield and presents its potential as an active reducing agent
Unraveling seasonality in origin and processing of carbonaceous aerosols over western India using dual-carbon isotopes
No full textThis study investigates the sources and characteristics of PM2.5 in Ahmedabad, a rapidly growing city in western India situated between the highly polluted Indo-Gangetic Plain and the pristine Arabian Sea. Chemical, optical, and dual-carbon isotope (13C and 14C) analyses were conducted to study carbonaceous aerosols (CAs). PM2.5 samples were collected from November 2020 to June 2021, covering postmonsoon, winter, spring, and summer seasons. CAs contributed 42 ± 10%, 53 ± 11%, 55 ± 12%, and 29 ± 6% of the PM2.5 mass during these seasons, respectively. Of this, 64 ± 3%, 64 ± 3%, 56 ± 3%, and 49 ± 4% originated from biomass burning (BB) or biogenic sources (fbio), as estimated from radiocarbon analysis. Stable carbon isotope ratios (δ13C) showed higher values in postmonsoon (−25.4 ± 0.8‰), followed by lower values in winter (−25.9 ± 0.4‰) and the lowest and similar values during spring and summer (−26.5 ± 0.3‰). These changes in δ13C values aligned with the CA oxidation proxy from aerosol mass spectrometry (f44), attributable to atmospheric processing of organic carbon (OC) rather than source shifts. A lower value of fbio_BC (0.20 ± 0.08) compared to that of fbio_OC (0.62 ± 0.07) suggests the contribution of biogenic sources to OC. The ratio of fbio_OC/fbio_BC is proposed as a proxy to differentiate biogenic contributions to CAs. This ratio suggests that the highest biogenic influence is in summer, followed by spring, postmonsoon, and winter. Even though the higher biogenic contribution was in the summer, winter aerosols were highly oxidized as they were transported from the polluted Indo-Gangetic Plain, as evidenced by elevated δ13C and f44. The findings highlight that even in a large urban center, regional transport of aged aerosols and seasonal biomass burning play a significant role in local air quality, alongside local fossil fuel emissions
A geometric-analytic proof of the reverse isoperimetric inequality
No full textWe present the first geometric-analytic proof of the reverse isoperimetric inequality for black holes in any dimension. The proof holds for compact Riemannian hypersurfaces in AdS (and dS) and seems to be a generic property of black holes in the extended phase space formalism. Using Euclidean gravitational action, we show that, among all hypersurfaces of given volume, the round sphere in the -dimensional (Anti-)de Sitter space maximizes the area (and hence the entropy). This analytic result is supported by a geometric argument in a decomposition of spacetime: gravitational focusing enforces a strictly negative conformal deformation, and the Sherif–Dunsby rigidity theorem then forces the deformed 3-sphere to be isometric to round 3-sphere, establishing the round sphere as the extremal surface, in fact, a maximally entropic surface. Our work establishes that the reversal of the usual isoperimetric inequality occurs due to the structure of curved background governed by Einstein's equation, underscoring the role of gravity in the reverse isoperimetric inequality for black hole horizons in (A)dS space
Advanced nanomicelles for targeted glioblastoma multiforme therapy
No full textGlioblastoma multiforme (GBM) is the most aggressive and malignant primary brain tumor, classified as grade IV by the WHO. Despite standard treatments like surgical resection, radiotherapy and chemotherapy (i.e. temozolomide), GBM's prognosis remains poor due to its heterogeneity, recurrence and the impermeability of the blood-brain barrier (BBB). The exact cause of GBM is unclear with potential factors including genetic predisposition and ionizing radiation. Innovative approaches such as nanomicelles-nanoscale, self-assembled structures made from lipids and amphiphilic polymers show promise for GBM therapy. These nanocarriers enhance drug solubility and stability, enabling targeted delivery of therapeutic agents across the BBB. This review explores the synthesis strategies, characterization and applications of nanomicelles in GBM treatment. Nanomicelles improve the delivery of both hydrophobic and hydrophilic drugs and provide non-invasive delivery options. By offering site-specific targeting, biocompatibility, and stability, nanomicelles can potentially overcome the limitations of current GBM therapies. This review highlights recent advancements in the use of nanomicelles for delivering therapeutic agents and nucleic acids addressing the critical need for advanced treatments to improve GBM patient outcomes
Participation of host cell proteins in inclusion bodies of non-segmented RNA virus infected cells: a molecular insight
No full textNegative-sense RNA viruses (NSVs) carrying a non-segmented genome encompass a broad group of viruses responsible for numerous human diseases such as rabies, mumps, measles, respiratory illness and encephalitis. Viruses replicate intracellular and interact with various host proteins to evade the immune response and persist within the host. A salient trait of NSVs is their ability to form cytoplasmic inclusion bodies (IBs) which are believed to serve as pivotal sites for viral replication. The formation of viral IBs is a complex process involving the recruitment of viral RNA and its proteins along with cellular components. These different constituents of IBs fulfil diverse roles depending on the structure and composition which remains specific to each virus. Therefore, understanding the viral strategies underlying IB formation is imperative. Numerous studies have explored the relationship between virus-induced IBs and host cell factors. This review aims to summarize how cellular factors participate in the formation of distinct viral IBs among non-segmented NSVs