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The 2004 tsunami and coastal subsidence resulted in 97% mangrove loss in the Nicobar Islands (India), leading to major social-ecological change. We assessed how the Nicobar mangrove social-ecological system (SES) responded to the 2004 event using the adaptive cycle (AC) framework. We describe the changes across AC phases (collapse-Ω, reorganisation-α, growth-r, and conservation-K) concerning various capital types (natural, built, human, social), connectedness and resilience. The subsidence and tsunami triggered a rapid collapse (Ω) in the mangrove SES, particularly depleting natural and built capitals. Despite declines in social and human capital, some knowledge and skills were retained within Nicobari communities. We suggest that locally managed interventions involving mangrove restoration are critical to escape the poverty trap caused by resource insufficiency hindering growth. The AC model helps visualise and describe temporal changes, preparing for recovery challenges. This approach is relevant to SESs beyond Nicobar, offering insights for sites confronting similar social-ecological dynamics and challenges.

Globally, climate warming is increasing air temperatures and changing river flows, but few studies have explicitly considered the consequences for lake temperatures of these dual effects, or the potential to manage lake inflows to mitigate climate warming impacts. Using a one-dimensional model, we tested the sensitivity of lake temperatures to the separate and interacting effects of changes in air temperature and inflow on a small, short-residence time (annual average ≈ 20 days), temperate lake. Reducing inflow by 70% increased summer lake surface temperatures 1.0-1.2 °C and water column stability by 11-19%, equivalent to the effect of 1.2 °C air temperature warming. Conversely, similar increases in inflow could result in lake summer cooling, sufficient to mitigate 0.75 °C air temperature rise, increasing to more than 1.1 °C if inflow temperature does not rise. We discuss how altering lake inflow volume and temperature could be added to the suite of adaptation measures for lakes.

In the present study, the impact of urban growth on green spaces in Kolkata Metropolitan City (KMC) was evaluated using the multi-temporal satellite observations spanning the last four decades (1990-2022). The study exhibited a rapid rise in urban areas (178.38% growth; net increase 498 sq.km), leading to a significant conversion of areas into moderate to very high built-up density zones. This urbanization has markedly altered the green-blue infrastructure, notably causing a 27% decline in urban green space (UGS) resulting a net loss of 254 sq.km. Fragmentation analysis exhibited a trend of compact, infill development in urban regions, contrasting with outgrowth, which has influenced both the cluster size and quality of UGS over the decades. The multi-indices and biophysical characterization of UGS concluded a deteriorating trend in terms of quantity (- 27.9%) and quality as well with reference. However, the existing UGS are primarily scattered and having less dense. Spatial estimation of above ground biomass (AGB) of UGS using regression analysis of field-derived AGB and L-band SAR backscatter depicted a dominance of low AGB (< 30 t/ha^-1) across KMC, while the certain zones with improved UGS exhibited moderate AGB levels (50-100 t/ha^-1). The fuzzy AHP-based multi-criteria analysis of urban ecological quality exhibited severe ecological deterioration in the central urban areas, moderate to high in peri-urban regions, and comparatively improved ecological conditions in the peripheral rural parts of KMC. The study also identified major native tree species for plantation strategies comprising urban afforestation, rooftop gardens, and the development of green corridors in ecologically deficient hotspot zones to improve the ecological quality within the urban landscape.

In this study, we conducted an extensive analysis of 252 bioactive compounds derived from native spices and herbs for their potential anti-breast cancer activity against sterol regulatory element-binding protein (SREBP), using in silico techniques. To evaluate the oral bioavailability, overall pharmacokinetics, and safety profiles of these compounds, we employed Lipinski's rule of five and ADME descriptors, which depicted 66 lead molecules. These molecules were then docked with the SREBP using molecular docking tools, which revealed that diosgenin and smilagenin were the most promising hits compared to the reference inhibitor betulin, with average binding affinities of - 7.42 and - 7.37 kcal/mol and - 6.27 kcal/mol, respectively. To further assess the stability of these complexes along with betulin, we conducted molecular dynamics simulations over a 100 ns simulation period. We employed various parameters, including the root-mean-square deviation, root-mean-square fluctuation, solvent-accessible surface area, free energy of solvation, and radius of gyration, followed by principal component analysis. Furthermore, we evaluated the toxicity of the selected compounds against various anticancer cell lines, as well as their metabolic activity related to CYP450 metabolism and biological activity spectrum. Based on these results, both molecules exhibited promising drug candidate potential and could be utilized for further experimental analysis to elucidate their anticancer potential.

Since the coronavirus disease 2019 (COVID-19) outbreak, research has been conducted on treatment and countermeasures against the causative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the development of new seeds is urgently needed because viruses have the characteristic of becoming resistant through mutation. We hypothesize that endophytes produce antiviral substances to combat foreign viruses in host plants. According to this hypothesis, the seeds of therapeutic agents for infectious diseases could be obtained from endophytes by culture experiments. This report found that Aspergillus sp. endophyte isolated from Catharanthus roseus produced ( +)-eupenoxide and its 3-ketone form with anti-SARS-CoV-2 activity. In addition, ( +)-eupenoxide-3,6-diketon was discovered as a new compound with potent 3C-like protease inhibitory activity (IC₅₀: 0.048 μM) by synthesis based on ( +)-eupenoxide. This finding could be an important evidence that endophytic fungi symbiosis with medicinal plants is useful as antiviral producers.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder which is caused by abrupt degeneration of dopaminergic neuronal cells in the substantia nigra pars compacta (SNPc) area of the midbrain. Adenosine A_2A receptors have become promising therapeutic targets for PD; however, many A_2A receptor antagonists face challenges, such as limited accessibility or failure in clinical trials due to poor selectivity and bioavailability. To identify novel A_2A receptor antagonists, a 3D-QSAR-pharmacophore modeling approach was employed, involving virtual screening of ZINC, NCI, and MayBridge databases. The virtual hits were filtered via ADMET criteria to select compounds with favorable bioavailability and solubility profiles. From the MayBridge database, a potent monocyclic A_2A receptor antagonist, AW00032 (N-(furan-2-ylmethyl)-5-methylthiazole-4-yl) thiophene-2-sulfonamide, was identified. AW00032 possessed key pharmacophoric features: two lipophilic hydrogen bond acceptors, one hydrophobic aliphatic/aromatic group, and one aromatic ring. Docking analysis revealed AW00032 had a strong binding affinity for A_2A receptors (1.23 nM, ∆G - 10.49 kcal/mol), and its ADMET profile indicated good bioavailability. In 6-OHDA induced SH-SY5Y cells, AW00032 increased dopamine levels and tyrosine hydroxylase (TH) expression, demonstrating its potential as an A_2A receptor antagonist. AW00032, discovered through 3D-QSAR pharmacophore modeling, also reduced reactive oxygen species (ROS) levels and showed depletion in mitochondrial dysfunction in 6-OHDA-induced SH-SY5Y cells. It exhibited A_2A receptor antagonist activity comparable to the standard antagonist ZM241385, partially restoring dopamine and TH levels. Furthermore, AW00032 improved behavioral symptoms in haloperidol-induced C-57 bl/6 mice.

NiaR is a regulatory protein that represses the expression of proteins involved in the de novo biosynthesis and uptake of nicotinic acid (NA), with NA acting as a co-repressor. The previously published structure of NiaR from Thermotoga maritima (TmNiaR) identified it as a functional homodimer containing a transition metal ion in a suspected NA-binding pocket. Here, we present the crystal structure of NA bound to the iron-metalated form of TmNiaR. Supported by spectroscopic and solution studies, this structure shows that NA binds to a protein-bound ferrous ion via its ring nitrogen. In addition, the carboxylate group on NA interacts with Tyr108 from the dyad-related subunit, repositioning the likely DNA-binding domains of the dimer to promote high-affinity interactions with DNA operators. The specificity of TmNiaR for NA can be explained by the hydrogen bonding scheme within the NA-binding pocket.

The identification of different air pollution sources is essential to effectively control atmospheric pollution, particularly in megacities of emerging countries with rapid economic development, such as the Metropolitan Area of Lima-Callao (MALC). The objective of this research was to identify the main sources of particulate matter pollution by applying bivariate polar plots and the k-means clustering algorithm. These statistical techniques were applied to hourly in situ data of four variables collected over a 5-year period (2015-2019) by the Automatic Air Quality Monitoring Network of the MALC: wind direction, wind speed, PM₁₀, and PM_2.5 concentrations. Average PM₁₀ concentrations ranged from 34 μg m^-3 (CDM station) to 126.7 μg m^-3 (VMT station), while average PM_2.5 concentrations ranged from 16.8 μg m^-3 (CDM station) to 41.2 μg m^-3 (ATE station). The diurnal variation of PM presented two peaks, one in the morning (from 0800 to 1000 h) and the other at night (from 1900 to 2300 h), with the highest concentrations of PM₁₀ recorded at the ATE (0800 h: 155.8 μg m^-3) and VMT (2100 h: 154.6 μg m^-3) stations, and PM_2.5 at the ATE station (0800 h: 60.3 μg m^-3 and 2300 h: 37.5 μg m^-3). The results showed that the contributions of PM₁₀ are directly related to emissions from industrial activities, automotive fleet, construction, demolition, wind erosion, and the suspension and resuspension of particulates from unpaved roads. Meanwhile, high concentrations of PM_2.5 are mainly attributed to vehicle exhaust emissions, industrial emissions, secondary particulate formation, and drag by the action of the winds. The major source of particulate matter contamination is the vehicle fleet, and within this, automobiles, station wagons, combi vans, and 2 and 3-wheel motorcycles are those that have the greatest contribution. These results were supported by non-parametric statistical tests such as Kruskal-Wallis and Mann-Whitney U and validated by the conditional bivariate probability function. The findings of this work may help to implement pollution prevention and control strategies in the future within this South American megacity.