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Simple Summary: Given the potential impact of climate change on the distributions of endemic species, it is critical to implement species recovery and habitat management measures to protect threatened species. This study used MaxEnt modeling to assess the species' habitat suitability in varying climate scenarios in the Western Himalayas and identified ten influential drivers. Our field-based observations of Tragopan melanocephalus show that the species typically lives at elevations between 1850 and 3800 m, which is consistent with the species' reported affinity for extremely high elevations between 1500 and 4000 m above sea level. Our findings reveal that areas with high and moderate suitability for the species are patchily distributed throughout the Western Himalayas, ranging from northeastern Pakistan to central Himachal Pradesh and Uttarakhand. Moreover, there are continuous strips of highly suitable habitats along the Pakistan–Afghanistan border, in the Kashmir region, and in the Annapurna region of Uttarakhand. The study observed that the Western Tragopan's habitat suitability may increase under future climate change scenarios, but additional research is needed to avert population collapses and identify other potential drivers of local extinction occurrences. To support increased biodiversity and lower risks under current and anticipated future climatic conditions, it is advised that the suitable areas identified be designated as nature reserves. According to the study's findings, a more effective wildlife management strategy might significantly help with the reintroduction of the Tragopan melanocephalus population into its suitable habitats in western Himalaya, thereby advancing the global objectives set for the UN Decade of Ecosystem Restoration targets (2021–2030). The impact of a changing climate, particularly global warming, often harms the distribution of pheasants, particularly those with limited endemic ranges. To effectively create plans of action aimed at conserving species facing threats such as the Western Tragopan, (Tragopan melanocephalus; Gray, 1829; Galliformes, found in the western Himalayas), it is crucial to understand how future distributions may be affected by anticipated climate change. This study utilized MaxEnt modeling to assess how suitable the habitat of the targeted species is likely to be under different climate scenarios. While similar studies have been conducted regionally, there has been no research on this particular endemic animal species found in the western Himalayas throughout the entire distribution range. The study utilized a total of 200 occurrence points; 19 bioclimatic, four anthropogenic, three topographic, and a vegetation variable were also used. To determine the most fitting model, species distribution modeling (SDM) was employed, and the MaxEnt calibration and optimization techniques were utilized. Data for projected climate scenarios of the 2050s and 2070s were obtained from SSPs 245 and SSPs 585. Among all the variables analyzed; aspect, precipitation of coldest quarter, mean diurnal range, enhanced vegetation index, precipitation of driest month, temperature seasonality, annual precipitation, human footprint, precipitation of driest quarter, and temperature annual range were recognized as the most influential drivers, in that order. The predicted scenarios had high accuracy values (AUC-ROC > 0.9). Based on the feedback provided by the inhabitants, it was observed that the livability of the selected species could potentially rise (between 3.7 to 13%) in all projected scenarios of climate change, because this species is relocating towards the northern regions of the elevation gradient, which is farther from the residential areas, and their habitats are shrinking. The suitable habitats of the Tragopan melanocephalus in the Himalayan region will move significantly by 725 m upwards, because of predicted climate change. However, the fact that the species is considered extinct in most areas and only found in small patches suggests that further research is required to avert a further population decline and delineate the reasons leading to the regional extinction of the species. The results of this study can serve as a foundation for devising conservation strategies for Tragopan melanocephalus under the changing climate and provide a framework for subsequent surveillance efforts aimed at protecting the species. [ABSTRACT FROM AUTHOR]

The ability of microorganisms to generate resistance outcompetes with the generation of new and efficient antibiotics. Therefore, it is critically required to develop novel antibiotic agents and treatments to control bacterial infections. Green synthesized metallic and metal oxide nanoparticles are considered as the potential means to target bacteria as an alternative to antibiotics. Nanoconjugates have also attracted attention because of their increased biological activity as compared to free antibiotics. In the present investigation, silver nanoparticles (AgNPs), zinc oxide nanoparticles (ZnO NPs), copper oxide nanoparticles (CuO NPs), and iron oxide nanoparticles (FeO NPs) have been synthesized by using leaf extract of Ricinus communis. Characterization of nanoparticles was done by using UV–Vis Spectroscopy, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Energy Dispersive X-Ray Analyzer, X-ray Diffraction Analysis, and Dynamic Light Scattering Particle Size Analyzer. Interestingly, Streptomycin when combined with AgNPs, ZnO NPs, CuO NPs, and FeO NPs showed enhanced antibacterial activity against clinical isolates of S. aureus which suggested synergism between the nanoparticles and antibiotics. The highest enhanced antibacterial potential of Streptomycin was observed in conjugation with ZnO NPs (11 ± 0.5 mm) against S. aureus. Minimum inhibitory concentration of conjugates of AgNPs, ZnO NPs, CuO NPs, and FeO NPs with streptomycin against S. aureus was found to be 3.12, 2.5,10, and 12.5 μg/mL respectively. The considerable point of the present investigation is that S. aureus, which was resistant to streptomycin becomes highly susceptible to the same antibiotic when combined with nanoparticles. This particular observation opens up windows to mitigate the current crisis due to antibiotic resistance to combat antimicrobial infections efficiently. [ABSTRACT FROM AUTHOR]

Key message: Exogenous potassium (K+) and endogenous hydrogen sulfide (H2S) synergistically alleviate drought stress through regulating H+-ATPase activity, sugar metabolism and redox homoeostasis in tomato seedlings. Present work evaluates the role of K+ in the regulation of endogenous H2S signaling in modulating the tolerance of tomato (Solanum lycopersicum L. Mill.) seedlings to drought stress. The findings reveal that exposure of seedlings to 15% (w/v) polyethylene glycol 8000 (PEG) led to a substantial decrease in leaf K+ content which was associated with reduced H+-ATPase activity. Treatment with sodium orthovanadate (SOV, PM H+-ATPase inhibitor) and tetraethylammonium chloride (TEA, K+ channel blocker) suggests that exogenous K+ stimulated H+-ATPase activity that further regulated endogenous K+ content in tomato seedlings subjected to drought stress. Moreover, reduction in H+-ATPase activity by hypotaurine (HT; H2S scavenger) substantiates the role of endogenous H2S in the regulation of H+-ATPase activity. Elevation in endogenous K+ content enhanced the biosynthesis of H2S through enhancing the synthesis of cysteine, the H2S precursor. Synergistic action of H2S and K+ effectively neutralized drought stress by regulating sugar metabolism and redox homoeostasis that resulted in osmotic adjustment, as witnessed by reduced water loss, and improved hydration level of the stressed seedlings. The integrative role of endogenous H2S in K+ homeostasis was validated using HT and TEA which weakened the protection against drought stress induced impairments. In conclusion, exogenous K+ and endogenous H2S regulate H+-ATPase activity which plays a decisive role in the maintenance of endogenous K+ homeostasis. Thus, present work reveals that K+ and H2S crosstalk is essential for modulation of drought stress tolerance in tomato seedlings. [ABSTRACT FROM AUTHOR]