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Background

Antimicrobial resistance (AMR) is a major worldwide health concern, characterized by the ability of microorganisms to withstand the effects of medications that once effectively treated infections. Phage therapy has emerged as a promising alternative for management of multidrug-resistant (MDR) bacterial infections. Acinetobacter baumannii (A. baumannii) exemplifies the emergence of bacteria resistant to clinically relevant antimicrobials, leading to severe nosocomial infections and exhibiting extensive and pan drug-resistant (XDR and PDR) traits. In response, this study isolated A. baumannii virulent phage designated as vB_AbaP_PhE54 against carbapenem-resistant A. baumannii (CRAB) pathogen and examined its morphological characteristics using an electron micrograph. Phage stability at different temperatures, pH, chloroform, safety, therapeutic evaluation, and growth kinetics have been analyzed.

Results

The A. baumannii phage vB_AbaP_PhE54 belongs morphologically to the Podoviridae family with very short, noncontractile tails, the phage demonstrated high thermal tolerance and infectivity across a pH range of 4–11, although it displayed a narrow host range. One-step growth kinetics indicated a burst size of 85 PFU (Plaque Forming Unit) per infected cell and a latent period of 20 min. Additionally, therapeutic efficiency in a mouse model showed total elimination of CRAB pathogen from lungs homogenates of mice and recovery from lung inflammation in all infected mice. On the other hand, safety evaluation of isolated phage revealed no adverse effects on structural or morphological tissue integrity.

Conclusions

These findings suggest that A. baumannii phage vB_AbaP_PhE54 could be a viable safe therapeutic option against A. baumannii infections, warranting further research into its clinical applications.

The renovation and evaluation of building energy-saving projects can provide important support for building an energy-saving society. The study proposes using the contract energy management model to analyze building energy-saving projects and construct an evaluation index system. We also innovatively integrated the Analytic Hierarchy Process and Entropy Weight Method to calculate the weights of indicators, in order to leverage the effective influence of subjective and objective factors. Finally, we used Grey Cluster Analysis to obtain the evaluation effect of building energy-saving projects. Through weight calculation and evaluation analysis, it was found that the energy-saving rates of year-end electricity consumption and air conditioning electricity consumption in buildings after energy-saving renovation were 59.80% and 54.95%, respectively. The overall effectiveness of energy-saving buildings was above 50%, indicating a significant energy-saving effect. In the indicator evaluation system, the weight results of energy-saving service company indicators were relatively high, with values of 0.52, 0.48, and 0.51, respectively. The transformation effect was relatively good. The building energy-saving cost and economic benefits obtained from a 65% energy-saving rate were 3 million yuan and 530,000 yuan, respectively, which were significantly better than the simulation results of other energy-saving rates. The contract energy management model based on the fusion weight method and grey clustering method has superiority, which is effective for evaluating building energy-saving projects. It also provides technical reference and scientific suggestions for building energy-saving renovation.

Recently, the Belle and LHCb Collaborations have measured the (Lambda ^+_c rightarrow p K^- pi ^+) decay and reported the (K^- p) invariant mass distribution, which shows a clear cusp structure around the (eta Lambda ) threshold. In this work, we have analyzed this process by considering the triangle mechanism and the S-wave pseudoscalar meson-octet baryon interactions within the chiral unitary approach, which dynamically generates the (Lambda (1670)). Our results are in good agreement with the Belle measurements, which implies that the cusp structure around (eta Lambda ) threshold could be associated with the (Lambda (1670)) with the molecular nature.

Rapid urbanization poses significant challenges to ecosystem services and environmental integrity. This study presents an integrated geospatial approach to analyze Land Use Land Cover (LULC) changes and their impact on Ecosystem Service Value (ESV) in Nashik, India, from 2017 to 2023. It employs open-source ESRI LULC datasets developed from Sentinel-2 satellite imagery to accurately map built-up areas, forests, agricultural lands, water bodies, and barren lands. ESV estimation utilized the Benefit Transfer Method (BTM) with specific coefficients tailored to different LULC types. Further, an elasticity analysis was conducted to evaluate the responsiveness of ESV to LULC changes, while sensitivity analysis tested the reliability of ESV estimates. From 2017 to 2023, Nashik experienced notable LULC changes: built-up areas expanded by 17.8%, barren lands by 20.1%, and forest cover increased by 59.4%. Meanwhile, agricultural land decreased by 20.1%, and water bodies by 6.5%. These changes resulted in an overall 9.6% decline in ESV, from $3.02 million/ha/year to $2.73 million/ha/year. ESV of water bodies fell from 1.705 to 1.600, forest ESV rose from 0.098 to 0.156, and agricultural ESV declined from 1.215 to 0.971. Elasticity analysis revealed that ESV changes were most sensitive to the expansion of built-up areas and the reduction of agricultural land, while the sensitivity analysis confirmed the robustness of the results, indicating low sensitivity to changes in coefficient values. These results underscore the loss of blue-green spaces and biodiversity due to urban expansion, highlighting the need for regular LULC and ESV assessments for sustainable urban planning and focussed conservation efforts.

Transition metal carbides, nitrides, and oxides are pivotal materials due to their Dirac surface states and high carrier mobility. This study investigates the superconductivity and topological surface states of three such compounds: YC, YN, and YO. Utilizing density functional perturbation theory and maximally localized Wannier functions, we thoroughly examine the superconducting and electronic properties of these materials, both with and without the influence of spin-orbit coupling. Our findings reveal that YC and YO are metallic superconductors. When SOC is included, YC exhibits a high critical temperature of up to 40.9 K, while YO, characterized by good stability, has a lower critical temperature of 12.56 K. The dispersion of surface states projected onto the (010) plane confirms the presence of non-trivial (mathbb {Z}_{2}) invariant surface states in YC. Furthermore, YN demonstrates semimetal behavior and a critical temperature of 22 K under SOC. The surface states projected onto the (101) plane display non-trivial (mathbb {Z}_{2}) invariant for both YO and YN. The topological superconducting nature of YC, YN, and YO highlights their significant implications for future technological applications.

Heavy metals and metalloids are ubiquitous and persistent in the environment. Anthropogenic activities, including land use change, industrial emissions, mining, chrome plating, and smelting, escalate their distribution and accumulation in terrestrial ecosystems. Priority metals, including lead, chromium, arsenic, nickel, copper, cadmium, and mercury, pose enormous risks to public health, ecological safety, and biodiversity. The adverse effects of heavy metals on plant-animal interactions, pollen viability, species fitness, richness, and abundance are poorly understood. Hence, this review summarises the critical insights from primary investigations on the key sources of heavy metal pollution, distribution pathways, and their adverse effects on plants and pollinators. This study provides insights into how heavy metals compromise nectar quality, pollen viability, plant-pollinator growth, and reproduction. Biotic pollinators are responsible for approximately 90% of the reproduction of flowering plants. Heavy metals adversely affect pollinators that rely on angiosperms for nectar and pollen. Heavy metals interrupt pollinators’ and plants’ growth, reproduction, and survival. Evidence showed that bees near gold mines had their olfactory learning performances and head sizes reduced by 36% and 4% due to heavy metals exposure. Cadmium (Cd) interrupts the redox balance, causes oxidative stress, alters gut microbiota, and reduces the survival rate of Apis cerana cerana. Excess Cd exposure reduced the flight capacity, loss of mitochondria, and damaged muscle fibre of Bombus terrestris, while Zn stress reduced egg production and hatchability of Harmonia axyridis. Furthermore, heavy metals alter flower visitation, foraging behaviour, and pollination efficiency.

Graphical Abstract

The unique features of trimetallic nanoalloys to be used in biomedical applications have taken more attention instead those of mono and bimetallic nanoparticles. Leaf aqueous extract of Nitraria retusa was utilized for the first time to synthesize trimetallic Se/ZnO/CuO (TSZC) nanoalloys. Data displayed the formation of crystallographic and spherical TSZC with an average size of 47.69 ± 1.95 nm by the action of active molecules in N. retusa extract. EDX analysis reveals the existing Se, Zn, and Cu peaks at specific bending energies with weight percentages of 17.03, 9.44, and 8.36% respectively. TSZC showed promising antimicrobial activity against Staphylococcus aureus, Escherichia coli, Candida albicans, and Penicillium glabrum, superior the activity of positive control. The clear zones ranging from 12.3 ± 0.6 to 32.7 ± 0.5 mm were attained due to TSZC treatment with MIC values of 12.5 µg mL^–1 for E. coli, C. albicans, and P. glabrum, and 50 µg mL^–1 for S. aureus. The maximum DPPH scavenging activity (90.1 ± 0.2%) was attained at 1000 µg mL^–1 TSZC compared to ascorbic acid (98.3 ± 0.2%). The IC₅₀ of TSZC nanoalloys against normal cell line (WI38) was 294.9 ± 4.4 µg mL^–1 compared to IC₅₀ against cancer cells (Caco-2 = 83.01 ± 1.1; Mcf7 = 91.7 ± 1.2 µg mL^–1) Which indicates that the TSZC are targeted cancer cells at low concentrations. Finally, the inhibition of α-amylase and α-glucosidase by TSZC with IC₅₀ values of 23.2 ± 3.8 and 32.1 ± 2.6 µg mL^–1 respectively compared to acarbose as a positive control (IC₅₀ = 10.9 ± 1.5 and 15.9 ± 1.8 µg mL^–1 for α-amylase and α-glucosidase respectively) indicates the superior antidiabetic activity in-vitro.

The dynamics of fluvial erosion responds to soil erosion and surface runoff on hillslopes due to land use and environmental fragility, conditioned by the soil, geology, relief, and rainfall rate. Despite the increasing problems associated with fluvial erosion in Brazil, little information is available on bedload transport in headwater catchments under intense agricultural activity. Therefore, this study sought to characterize the fluvial erosion processes and bedload dynamics in an experimental catchment in southern Brazil located at the edge of the Brazilian Meridional plateau, which is representative of a large area of high environmental fragility and intense agricultural activity in Southern Brazil. The Guarda Mor River drains a headwater catchment (18.5 km²) with undulating and hilly terrain with fragile soils and intense agricultural activity controlling fine and coarse sediment supply downstream. During 11 major rainfall-runoff events, monitoring was conducted to measure streamflow, bedload transport rates, sediment size, and hydraulic parameters, such as Manning’s n values and viscous layer thicknesses. A rating curve was established based on 40 streamflow and bedload discharge measurements taken at different water levels and stages along the hydrograph. In addition, a river portion (gravel bed) was characterized as well as the granulometric characteristics of its surface and subsurface layers. The results showed that the transport pattern is influenced by factors other than hydraulic parameters alone, including the interdependence between successive events, armoring effects, and hysteresis. These factors are strongly related to the surface runoff and erosion observed on the hillslopes, which define the streamflow energy and the supply of sand fraction, respectively. A discussion is held on the bedload transport dynamics under non-equilibrium conditions in the modeling of fluvial erosion processes.