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Springs in the Sirmaur district of the North-Western Himalayas are vital freshwater sources; however, systematic, multi-seasonal data on their physicochemical quality, trace metal concentrations, and land use influences remain scarce. Thirty springs were assessed over 2 years (2021-2023) for physicochemical and heavy metal parameters, seasonal variations, and land use impacts using multivariate statistical methods. Water was neutral to mildly alkaline (pH 6.97-8.06) with moderate mineralization. Calcium and magnesium occasionally exceeded BIS standards, reflecting geogenic inputs from carbonate- and dolomite-rich formations. Lead exceeded permissible limits in both pre- and post-monsoon seasons (up to 0.0163 mg L⁻¹), and iron exceeded limits during pre-monsoon (up to 0.3004 mg L⁻¹), indicating localized anthropogenic and lithological influences. Water Quality Index (WQI) classified overall quality as "Good" (pre-monsoon 36.26; post-monsoon 37.63), with forested catchments consistently superior. A significant difference (p < 0.05) between agricultural and settlement springs during pre-monsoon indicates enhanced contaminant transport under low-flow conditions. Spearman correlation showed positive associations between pH and Ca, Zn, and Mn, reflecting mineral weathering. Principal component analysis (PCA) distinguished regional geogenic controls from site-specific anomalies shaped by land use and lithology. The study provides a comprehensive, data-driven understanding of spring water quality dynamics, offering insights for springshed management, pollution mitigation, and sustainable water resource planning in Himalayan headwaters.

Acinetobacter baumannii (A. baumannii) is a Gram-negative bacterium that creates an increasing burden on the healthcare system due to its ability to develop multidrug resistance. Sensitive, rapid and on-site detection of A. baumannii, which has been declared a critical priority pathogen by the World Health Organization, is of great importance. Today, secretory proteins of pathogenic organisms attract attention not only for their role in invasive processes but also as targets for early diagnosis. In this context, SPSFQ, a recently identified secretory protease, is a valuable target for the detection of A. baumannii at very low initial levels, before significant colonization occurs. In this study, ssDNA aptamers for SPSFQ were selected for the first time using the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) method. The two aptamer sequences identified through SELEX were named Apt1 and Apt2, with Kd values of 42.10 ± 6.7 nM and 26.98 ± 1.35 nM, respectively. An ultrasensitive EIS-based biosensor was developed using Apt2, achieving a detection limit of 5.44 fg/mL and a linear range of 1.0-10,000 fg/mL. The aptasensor exhibited good repeatability (RSD: 2.62%) and reproducibility (RSD: 6.62%), and also maintained satisfactory stability during storage. Furthermore, the developed biosensor demonstrated reliable and remarkable performance in real commercial human serum samples, with recovery values of 110.84% and 104.40% for serum samples spiked with 250 and 6500 fg/mL SPSFQ, respectively.

Root-knot nematodes (RKNs), Meloidogyne spp., exhibit a broad host range, threatening more than 3000 species of plants, including agriculturally important crops such as cotton (Gossypium hirsutum), tomato (Lycopersicon esculentum) and rice (Oryza sativa). Among the over 90 RKN species, the four most prevalent are M. incognita, M. arenaria, M. javanica, and M. hapla, with M. incognita being the most damaging. This paper reviewed the current RKN management strategies, including chemical nematicides, biological control, crop rotation, and resistant varieties, with a focus on the application of the revolutionary CRISPR/Cas genome editing tool in developing RKN resistance in plants. CRISPR/Cas has been widely utilized for improving crop traits due to its specificity, streamline, and inheritability. Recent progress has demonstrated the simplicity and robustness of CRISPR/Cas technology in improving plant traits. Among these, the development of nematode resistance by CRISPR/Cas knocking out of plant compatibility factors in model and commercial plants, has achieved significant progress. This review summarizes the RKN parasitism mechanisms and plant compatibility factors that would be promising CRISPR/Cas targets. The fundamentals and key aspects of CRISPR/Cas genome editing technology are addressed and discussed, and an example experimental pipeline for developing nematode resistance in cotton is described.

Potato early blight, caused by Alternaria solani, presents a significant threat to the potato industry. Existing detection methods for A. solani often fail to simultaneously achieve simplicity and accuracy. A gold-platinum (AuPt) nanozyme-assisted CRISPR/Cas12a system, termed the nanoparticle enzyme-assisted CRISPR detection (NACD assay) was developed. By integrating the precise target recognition of CRISPR with the enzyme-like activity of AuPt nanozymes, this system achieves simple, sensitive, and visual detection of A. solani. The NACD assay provided visual results through a distinct color change produced by the substrate catalyzed by the AuPt nanozyme. It can detect 100 copies/μL of the target dsDNA (A. solani 5.8S rRNA gene) and 10⁻³ ng/μL A. solani genomic DNA. This detection method demonstrates high specificity, with no cross-reactivity observed with three other pathogens. Moreover, the incorporation of a filter paper-based readout enables straightforward visual detection by the naked eye, making it particularly suitable for on-site testing. Overall, these features make it an effective on-site diagnostic tool, allowing the potato industry to manage early diseases more efficiently.

Optical switching of ferroelectric polarization is of interest for wireless and energy-efficient control of logic states. So far, this phenomenon has been widely demonstrated only in ferroelectric perovskites, while studies on other emerging ferroelectrics remain limited. In this regard, the paradigmatic example of a technologically relevant ferroelectric material is HfO₂. However, HfO₂ has a very wide bandgap, limiting light absorption. So far, the proposed strategies to enhance light absorption in HfO₂-based systems are detrimental to ferroelectric properties, i.e., bandgap lowering or on-purpose defect introduction, which reduce switchable polarization and increase the presence of leakage currents. Here, we show that good ferroelectric properties, i.e., sizeable polarization (up to 15 μC cm^-2), low leakage current (under 10^-6 A cm^-2), high endurance (up to 10⁸ cycles) and fast switching (< 50 ns), can be achieved in epitaxial Hf_0.5Zr_0.5O₂ films through an alternative strategy, BaTiO₃ capping. While ferroelectric properties are remarkable, we demonstrate that the presence of BaTiO₃ allows light absorption and the concomitant electric field generation, as supported by density functional theory calculations, which enables optical switching of polarization in Hf_0.5Zr_0.5O₂ under 405 nm illumination. It is observed that optical switching is more efficient in films with thicker BaTiO₃ capping layer. The high polarizability of BaTiO₃ contributes to minimizing degradation in the ferroelectric response of the system. The results presented here indicate that appropriate designs can be followed to obtain optical switching of polarization in ferroelectric HfO₂ while preserving main functional properties.

Advances in microfabrication technology have enabled precise control of surface geometry, which strongly influences cellular behavior, including adhesion, alignment, and differentiation. However, previous studies have employed diverse substrate materials and fabrication conditions, making it difficult to rigorously evaluate the pure geometric effects of the microstructures. Consequently, variations in physicochemical and mechanical properties, such as surface chemistry and stiffness, have confounded the interpretation of geometry-specific effects. To clarify the influence of microgeometry on cell behavior, particularly cell differentiation, stripe- and mesh-patterned polystyrene substrates were used to systematically investigate the relationship between surface geometry and cell behavior. Human mesenchymal stem cells (hMSCs) and C2C12 myoblasts were seeded on the substrates, and their adhesion morphology and alignment were observed using calcein-AM staining. Osteogenic and myogenic differentiation were subsequently induced, and the expression of differentiation markers was analyzed by immunostaining and RT-qPCR. In hMSCs, osteogenic differentiation was promoted in geometries that facilitated intercellular contact, whereas it was suppressed in highly confined geometries, such as stripes and meshes with greater ridge heights. In C2C12 myoblasts, a clear enhancement of myogenic differentiation was observed on striped substrates, where cells exhibited elongated morphologies aligned with the grooves, accompanied by an elevated expression of myogenin and dystrophin. These findings indicate that the differentiation-promoting or differentiation-suppressive effects of microgeometry are cell type-dependent and are governed by cellular alignment, intercellular interactions, and adhesion morphology. The insights gained from this study may contribute to the rational design of next-generation regenerative scaffolds and highlight the potential applications of microgeometric substrates in drug-screening platforms.

This study aimed to develop a comprehensive risk profile of four key occupational harmful factors-heat stress, inadequate illumination, noise, and respirable dust-within a representative ceramic manufacturing facility in Iran. Standardized instruments and protocols were used to assess four physical harmful factors. Dust concentration was measured via NIOSH 0600 using SKC pumps and nylon cyclones. Noise levels were recorded with a type 2 sound level meter (Extech 407732). Illuminance was measured with a GM1040 lux meter at a height of 0.85 m, and heat stress was evaluated using a wet-bulb globe temperature (WBGT) meter. The risk ratio (RR) was calculated for each harmful factor as a single risk index. An integrated risk assessment followed, incorporating RR values, the number of exposed workers, and exposure duration. Prioritization of harmful factors and similar exposure groups (SEGs) was performed using the Pareto principle. The findings revealed that the average levels of noise, illumination, respirable dust, and temperature in the studied ceramic industry were 82.88 dB(A), 114.83 lx, 4.15 mg/m³, and 21.01 °C, respectively. The RR matrix analysis identified respirable dust exposure as a high-risk factor, with a prioritization index exceeding 386%. In comparison, noise was classified as a medium-risk factor, with priority levels ranging from 321 to 386%. In contrast, poor illumination and heat stress were categorized as low-risk factors (integrated risk assessment (IRI) < 321%). Among the SEGs, the packing occupational group exhibited the highest comprehensive risk profile (IRI ≥ 379%) and was consequently identified as the top priority for control interventions in accordance with the Pareto principle. This risk-based framework offers a systematic approach for prioritizing occupational health interventions and optimizing resource allocation in industrial environments. Clinical trial number: This is not applicable.

Climate change is expected to intensify thermal stress in coastal ecosystems, threatening biodiversity and ecosystem functioning. In this study, we investigate species-specific and colony-level variation in thermal tolerance among three psammophilous ant species (Mycetophylax spp.) inhabiting Brazilian coastal dunes. Using critical thermal limits (CTmin and CTmax), linear mixed-effects models, and heritability estimates, we assessed the role of diel activity rhythms and genetic structure in shaping thermal performance. Results revealed that M. simplex, a nocturnal and substrate-specialized species, exhibited significantly lower CTmin and CTmax values compared to diurnal congeners, and that colony identity explained a substantial portion of variance (H² = 0.53 for CTmin, H² = 0.39 for CTmax). These findings suggest limited thermal resilience and evolutionary constraints in M. simplex, reinforcing its potential as a bioindicator of thermal vulnerability. Given projected warming and habitat disturbance in southeastern Brazil, we highlight the importance of integrating functional traits and genetic metrics into environmental monitoring and conservation planning.

ZnO has been used as template to prepare and regulate the structures of functional nanomaterials. Due to the structural characteristics of Zn, its nanomaterials are generally considered inert. This study presents an innovative ZnO-templated synthesis of hollow N-doped carbon materials with atomically dispersed Zn single atoms (Zn SA/NC), where ZnO uniquely serves dual roles as both structural template and Zn precursor. The synthesized Zn SA/NC exhibits remarkable bifunctionality, demonstrating exceptional electrocatalytic activity for H₂O₂ reduction (detection limit: 3.7 µM, sensitivity: 1285.7 µA·mM⁻¹·cm⁻²) and intrinsic peroxidase-like activity for TMB oxidation. Leveraging these properties, we developed a dual-mode H₂O₂ detection platform integrating electrochemical and colorimetric readouts. The work challenges conventional views on Zn's catalytic inertness by revealing that Zn-Nₓ sites enable efficient charge redistribution, while the hollow architecture enhances mass transport. This strategy bridges the gap between structural control and atomic dispersion in single-atom catalyst design.