Search Results (351)

Heavy rainfall events, characterized by extreme downpours that exceed 100 mm per day, pose an intensifying hazard to the densely settled valleys of the western Himalaya; however, their coupling with expanding urban land cover remains under-quantified. This study mapped the spatiotemporal exposure of built-up areas to heavy-day rainfall (HDR) across Jammu, Kashmir, and Ladakh and the adjoining areas by integrating daily Climate Hazards Group InfraRed Precipitation with Stations product (CHIRPS) precipitation (0.05°) with Global Human Settlement Layer (GHSL) built-up fractions within the Google Earth Engine (GEE). Given the limited sub-hourly observations, a daily threshold of ≥100 mm was adopted as a proxy for HDR, with sensitivity evaluated at alternative thresholds. The results showed that HDR is strongly clustered along the Kashmir Valley and the Pir Panjal flank, as demonstrated by the mean annual count of threshold-exceeding pixels increasing from 12 yr⁻¹ (2000–2010) to 18 yr⁻¹ (2011–2020), with two pixel-scale hotspots recurring southwest of Srinagar and near Baramulla regions. The cumulative high-intensity areas covered 31,555.26 km², whereas 37,897.04 km² of adjacent terrain registered no HDR events. Within this hazard belt, the exposed built-up area increased from 45 km² in 2000 to 72 km² in 2020, totaling 828 km². The years with the most expansive rainfall footprints, 344 km² (2010), 520 km² (2012), and 650 km² (2014), coincided with heavy Western Disturbances (WDs) and locally vigorous convection, producing the largest exposure increments. We also performed a forecast using a univariate long short-term memory (LSTM), outperforming Autoregressive Integrated Moving Average (ARIMA) and linear baselines on a 2017–2020 holdout (Root Mean Square Error, RMSE 0.82 km²; measure of errors, MAE 0.65 km²; R² 0.89), projecting the annual built-up area intersecting HDR to increase from ~320 km² (2021) to ~420 km² (2030); 95% prediction intervals widened from ±6 to ±11 km² and remained above the historical median (~70 km²). In the absence of a long-term increase in total annual precipitation, the projected rise most likely reflects continued urban encroachment into recurrent high-intensity zones. The resulting spatial masks and exposure trajectories provide operational evidence to guide zoning, drainage design, and early warning protocols in the region. Full article

This study examines the hydrodynamic and acoustic performance of plain NACA0018 hydrofoil and modified NACA0018 hydrofoils (foil with a cavity on suction surface) at a Reynolds number ($Re$) of $40,000$, which is indicative of small-scale turbines and marine applications. A cavity was created on suction side surface at 40–50% of the chord length, which is chosen for its efficacy in cavitation control. The present analysis examines the impact of the cavity on lift-to-drag-ratio ($L/D$) and cavity length at three cavitation numbers ($1.7$, $1.2$, and $0.93$) for plain and modified hydrofoils. Simulations demonstrate a significant enhancement of 7% in the lift-to-drag ratio relative to traditional designed foils. Contrary to earlier observations, the cavity length increases instead of decreasing for the modified hydrofoil. Both periodic steady and turbulent inflow conditions are captured that simulate the complex cavity dynamics and flow–acoustic interactions. It is found that a reduction in RMS velocity with modified blade suggests flow stabilization. Spectral analysis using Mel-frequency techniques confirms the cavity’s potential to reduce low-frequency flow-induced noise. These findings offer new insights for designing quieter and more efficient hydrofoils and turbine blades. Full article

Heavy metal pollution represents a pervasive environmental challenge that significantly exacerbates the ever-increasing crisis of antimicrobial resistance and the capacity of microorganisms to endure and proliferate despite antibiotic interventions. This review examines the intricate relationship between heavy metals and AMR, with an emphasis on the underlying molecular mechanisms and ecological ramifications. Common environmental metals, including arsenic, mercury, cadmium, and lead, exert substantial selective pressures on microbial communities. These induce oxidative stress and DNA damage, potentially leading to mutations that enhance antibiotic resistance. Key microbial responses include the overexpression of efflux pumps that expel both metals and antibiotics, production of detoxifying enzymes, and formation of protective biofilms, all of which contribute to the emergence of multidrug-resistant strains. In the soil environment, particularly the rhizosphere, heavy metals disrupt plant–microbe interactions by inhibiting beneficial organisms, such as rhizobacteria, mycorrhizal fungi, and actinomycetes, thereby impairing nutrient cycling and plant health. Nonetheless, certain microbial consortia can tolerate and detoxify heavy metals through sequestration and biotransformation, rendering them valuable for bioremediation. Advances in biotechnology, including gene editing and the development of engineered metal-resistant microbes, offer promising solutions for mitigating the spread of metal-driven AMR and restoring ecological balance. By understanding the interplay between metal pollution and microbial resistance, we can more effectively devise strategies for environmental protection and public health. Full article

This paper proposes a novel control strategy for a dual-stage grid-connected solar photovoltaic (PV) system designed to ensure reliable and efficient operation under unstable grid conditions. The strategy incorporates a Phase-Locked Loop (PLL)-based positive sequence estimator for accurate detection of grid voltage disturbances, including sags, swells, and fluctuations in solar irradiance. A dynamic DC-link voltage regulation mechanism is employed to minimize converter power losses and enhance the performance of the Voltage Source Converter (VSC) under weak grid scenarios. The control scheme maintains continuous maximum power point tracking (MPPT) and unity power factor (UPF) operation, thereby improving overall grid power quality. The proposed method is validated through comprehensive simulations and real-time hardware implementation using the OPAL-RT OP4510 platform. The results demonstrate compliance with IEEE Standard 519, confirming the effectiveness and robustness of the proposed strategy. Full article

The DFT method was used to evaluate the adsorption of methyl radicals and the evolution of ethane on the M(111) (M = Co, Ni, Pd, Pt) surfaces, eight metal atoms, in aqueous medium. A maximum of five and four radicals can be adsorbed on Co(111) and Ni(111), respectively, and six on Pd(111) and Pt(111) (top site). The ethane evolution occurs via the Langmuir–Hinshelwood (LH) or Eley–Rideal (ER) mechanisms. The production of ethane through the interaction of two adsorbed radicals is thermodynamically feasible for high coverage ratios on the four surfaces; however, kinetically, it is feasible at room temperature only on Co(111) at a coverage of (5/5) and on Pd(111) at a coverage ratio of 4/6, 5/6, and 6/6. Ethane production occurs via the ER mechanism: a collision with solvated methyl radical produces either C₂H₆ or ${\mathrm{C}\mathrm{H}}_2^{\ast }+{\mathrm{C}\mathrm{H}}_{4\left(\mathrm{a}\mathrm{q}\right)}$. On Pd(111) the product is only C₂H₆, on Pt(111), both products (C₂H₆ or ${\mathrm{C}\mathrm{H}}_2^{\ast }$) are plausible, and on Co(111) and Ni(111), only ${\mathrm{C}\mathrm{H}}_2^{\ast }+{\mathrm{C}\mathrm{H}}_{4\left(\mathrm{a}\mathrm{q}\right)}$ is produced. Further reactions of ${\mathrm{C}\mathrm{H}}_2^{\ast }$ with ${\mathrm{C}\mathrm{H}}_2^{\ast }$ or ${\mathrm{C}\mathrm{H}}_3^{\ast }$ to give ${\mathrm{C}}_2{\mathrm{H}}_4^{\ast }$ or ${\mathrm{C}}_2{\mathrm{H}}_5^{\ast }$ are thermodynamically plausible only on Pt(111); however, they are very slow due to high energy barriers, 1.48 and 1.36 eV, respectively. Full article

Ventilator-associated pneumonia (VAP) develops in patients who stay on mechanical ventilation for more than 48 h. In the presence of causative pathogens, the patient develops clinical signs such as purulent tracheal discharge, fever, and respiratory distress. A prospective observational study was carried out in the Intensive Care Unit (ICU) of Max Healthcare Centre, New Delhi, from 2020 to 2023. The study comprised 70 samples from patients diagnosed with VAP. This study thoroughly examined VAP-associated microorganisms and resistance in the hospital ICU. Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa were the most commonly reported pathogens. Significant drug resistance was seen in P. aeruginosa, K. pneumoniae, A. baumannii and Staphylococcus aureus. The heatmap also supported the antibiotic resistance data patterns obtained from conventional and automated systems of determination. Notably, Serratia marcescens, Escherichia coli, Klebsiella pneumoniae, Ralstonia insidiosa, and Ralstonia mannitolilytica, showed 60 to 100% of resistance to a number of antibiotics. Among all VAP patients, 31.42% early-onset and 68.57% late-onset VAP cases were detected. Out of 70 patients, 43 patients died (mortality rate 61.4%); majority of them suffered from late-onset VAP. The study goal was to describe the antibiotic resistance patterns and microbial ecology of the pathogens that were isolated from VAP patients. According to the heatmap analysis, a varied VAP microbiome with high prevalences of MDR in A. baumannii, P. aeruginosa, K. pneumoniae, and S. aureus was identified. To address the increasing prevalence of MDR VAP, the study highlights the critical need for improved VAP monitoring, strong infection control, and appropriate antibiotic usage. Full article

This study investigates the fabrication of sustainable polymer-based floor tiles utilizing recycled high-density polyethylene, low-density polyethylene, polypropylene, and polyethylene terephthalate. The process incorporates rice husk ash and natural sand to create eco-friendly construction materials. The materials underwent assessment for density, water absorption, flexural strength, compressive strength, and abrasive wear. The results reveal a density range from 1.07051 to 1.6151 g/cm³, and water absorption ranging between 0.1996% and 0.68434%. Optimal flexural and compressive strengths were observed for HD70R15S1 and PET70R15S15, reaching 5.96 and 24.7933 MPa, respectively. Three-body abrasive wear testing indicates a minimum of 0.03095 cm³ for PET70R15S15 and a maximum of 0.17896 cm³ for HD70R15S15 composites. Full article

Amidst global shifts in land use patterns due to urbanization, this study focuses on the rapid land use and land cover (LULC) changes in Midnapore City during the periods 2003–2014 and 2014–2024. The study employs Landsat 5 and 8 imagery with 30 m spatial resolution which were processed through Maximum Likelihood Classifier (MLC) algorithms. The results were attained through ArcGIS 10.2.2 and ERDAS IMAGINE 2014 software, with ground-truth validation using data from 117, 111, and 116 points for 2024, 2014, and 2003, respectively. For the validation, the kappa coefficient was calculated and achieved 87.3%, 88.1%, and 81.7% for 2024, 2014, and 2003, indicating substantial accuracy. Using statistical measures such as change matrix union, binary logistic regression, and correlation matrix analysis applied to classified LULC outputs and spatial drivers, the research highlights significant transformations in the region. The study reveals significant transformations, notably the conversion of 77% of forest areas and 5% of fallow land to built-up land. The increased rate of agricultural land conversion to built-up areas is evident after 2014, indicating rapid urban growth. These factors led to the reduction of LULC classes possessing substantial ecological value like forests and scrub lands which are becoming more accessible due to the increasing population. The results point out the drastic alteration of these developments and recommend a planning approach responsive to environmental needs for safeguarded ecological impacts. The research highlights the importance of reforestation, preservation of water bodies, and socio-economic surveillance in fostering urban management and sustainable development in Midnapore City. Full article

Rapid urbanization in the Global South poses challenges to ecological integrity, cultural heritage, and equitable access to green infrastructure. This study evaluates the effectiveness of recent green infrastructure projects in Addis Ababa, Ethiopia, including flagship parks and upgraded road corridors, through the lens of the Urban Nature Futures Framework (UNFF). To operationalize the UNFF’s three perspectives—Nature for Nature (NN), Nature for Society (NS), and Nature as Culture (NC)—a context-specific set of indicators was developed through the existing literature, global assessment frameworks, and stakeholder consultations. A mixed-methods approach, combining structured surveys with both qualitative and quantitative thematic analysis, was applied across four stakeholder groups: residents, park visitors, corridor users, and experts. The results indicate that while social benefits (NS) are widely recognized, ecological (NN) and cultural (NC) dimensions receive comparatively less emphasis. Regression analysis shows that education, employment, and green space use frequency significantly shape perceptions of NS and NC, while NN are more consistently shared across groups. This study demonstrates the practical value of the UNFF as an assessment tool and offers a replicable methodology for evaluating multifunctional green infrastructure. The findings underscore the need for more inclusive, biodiversity-positive, and culturally grounded urban renewal strategies. These insights are relevant for planners and policymakers aiming to foster equitable and resilient urban environments in rapidly growing cities. Full article

The Kashmir Valley, characterized by its rich loess–palaeosol sequences (LPSs), provides a unique geo-archive for reconstructing Late Quaternary climate dynamics. This study presents an extensive multi-proxy study, integrating high-resolution lithostratigraphy, geochemical analyses, stable isotope analysis of soil organic matter (δ¹³C-VPDB), and radiocarbon (¹⁴C) chronology of a sediment sequence approximately 200 cm thick, to unravel the complex interplay of climatic, pedogenic and environmental processes shaping the region spanning the Pleistocene–Holocene transition. The results establish a precise chronology of the sediment sequence between 13.4 ka and 7.2 ka, covering the transition from the Pleistocene to the Holocene Epoch. The results reveal distinct climatic and environmental conditions during this Epoch. The study reveals substantial loess deposition during the cold and dry glacial climate towards the end of the Pleistocene, followed by a shift to a warmer and wetter interglacial climate at the onset of the Holocene Epoch. This climatic shift led to the development of soil units with pronounced fluvial characteristics around 10 ka, eventually transitioning to fluvial deposition. Geochemical indices such as Ca/Ti, Al/Ti, Si/Ti, and K/Ti indicate low weathering intensity prior to 11 ka, followed by a noticeable increase around 11 ka, possibly driven by enhanced precipitation. δ¹³C values, ranging from −26.2‰ to −22.5‰, suggest C₃-dominated vegetation during the Late Pleistocene, indicating wetter climatic conditions. This study provides valuable insights into the intricate interactions between climate, soil development, and vegetation dynamics during the critical Late Pleistocene–Holocene transition in the Kashmir Valley. Full article

The present study focuses on how various firm characteristics influence their dividend payout policies. The study finds empirical evidence with regard to primarily two aspects of corporate dividend decisions—dividend increase and decrease, whose exploration is inadequate in the past literature. The random effect logistic regression has been considered in order to analyze the panel dataset from 2001–2002 to 2021–2022 including 3739 listed Indian firms. The empirical models are formatted based on the relevant dividend-related theories in the Indian context such as the residual theory, transaction cost theory, signalling theory, etc. Further, additional tests are conducted regarding the robustness of the reported results. The empirical results document that firm size, profitability, promoter holdings, cash holdings, and life cycle have a favourable influence on the propensity of both increasing and decreasing dividend payouts. In contrast, earnings volatility, leverage, and free cash flow reduce firms’ tendency to increase and decrease dividend payments. These results indicate that higher liquidity and ownership concentration provide firms with greater financial flexibility to adjust their dividend policies as per their prevailing opportunities. The findings of the study offer insightful information about how to arrange dividend policies with firm-specific traits which will be helpful for managers and investors to make better decisions. Full article

Climate-induced migration has emerged as a major concern in India and Bangladesh, due to their geographical vulnerability and socioeconomic conditions. Coastal areas, such as the Sundarbans and the Ganges–Brahmaputra Delta, face relentless threats due to rising sea levels, cyclones, and floods. These factors force millions to relocate, resulting in rural–urban transitions and cross-border movements that worsen urban challenges and socioeconomic vulnerabilities. For this, a systematic literature review of the Scopus database was undertaken using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A detailed review analysis of 65 papers was carried out. The study highlighted key climatic and non-climatic drivers of migration, including natural disasters, resource depletion, poverty, and poor governance. Despite existing adaptation strategies, such as early warning systems, micro-insurance, and climate-resilient practices, gaps remain in addressing long-term resilience and legal recognition for climate migrants. The research emphasizes the need for a holistic, multi-stakeholder approach, integrating adaptive infrastructure, sustainable livelihoods, and international cooperation. Recommendations include bridging research gaps, increasing community participation, and implementing global frameworks, like the Fund for Responding to Loss and Damage. Addressing climate migration through fair, inclusive measures is essential for building resilience and ensuring long-term development in the region. Full article

The present study investigated the uptake and health risks of potentially toxic elements (PTEs) by lotus (Nelumbo nucifera) cultivated in floating lake gardens of Dal Lake, Srinagar, India. Rapid urbanization and anthropogenic activities have led to PTE contamination in the lake, raising concerns about food safety and ecological sustainability. The objectives were to evaluate the physicochemical properties of water and sediment and to quantify PTEs (Cd, Cu, Cr, Co, Fe, Mn, Ni, and Zn) accumulation in different tissues of N. nucifera with associated health risks. A systematic sampling approach was adopted across four zones of the lake, collecting water, sediment, and plant tissues (August to October 2024). The results showed significant PTE contamination, with sediment showing high concentrations of Fe (1610.51 mg/kg), Mn (31.48 mg/kg), and Cr (29.72 mg/kg). Bioaccumulation factors indicated preferential PTE accumulation in roots, with Fe exhibiting the highest uptake (95.11). Translocation factors were low for most PTEs, suggesting limited mobility to edible parts. Health risk assessment indicated that Cr posed the highest non-carcinogenic risk (HRI = 1.8000 in rhizomes). The cumulative target hazard quotient (THQ) remained below 1, suggesting no immediate risk, but long-term exposure warrants concern. The study provided valuable information on the necessity of continuous monitoring and pollution mitigation strategies to ensure the food safety of floating lake garden-derived crops. Full article

Urban green spaces (UGSs) are vital in enhancing environmental quality, social well-being, and climate resilience, yet their distribution and accessibility remain uneven in many rapidly urbanizing cities. The 3–30–300 rule offers a structured guideline with which to assess urban greenness, emphasizing tree visibility, canopy cover, and green space proximity. However, its applicability in dense and resource-constrained urban environments has not been sufficiently examined. This study evaluates the feasibility of the 3–30–300 rule in Nagpur, India, using survey-based visibility assessments, NDVI-derived vegetation cover analysis, and QGIS-based accessibility evaluation. The study also introduces the Urban Greenness Exposure Index (UGEI), a composite metric that refines greenness assessment by capturing intra-zone variations beyond broad classifications. The findings reveal significant variations in urban greenness exposure across Nagpur’s ten municipal zones. Low-greenness zones report the highest tree visibility deprivation (below two trees), limited canopy cover (~7%), and restricted green space access (over 80% of residents lacking access within 300 m). The correlation analysis shows that higher canopy cover does not necessarily correspond to better visibility or accessibility, highlighting the need for integrated planning strategies. The study concludes that applying the 3–30–300 rule in high-density Indian cities requires localized adaptations, such as incentivizing street tree planting, integrating vertical greenery, and repurposing vacant lots for public parks. The UGEI framework offers a practical tool for identifying priority zones and guiding equitable greening interventions, based on insights drawn from the Nagpur case study. Full article