Search Results (144,956)

Airborne microplastics (AMPs) undergo ultraviolet (UV)-driven physicochemical aging during atmospheric transport, influencing cloud processes, greenhouse-gas release, and potential respiratory health impacts. Quantifying this transformation is particularly challenging for particles smaller than 10 µm and for polymers such as polyethylene terephthalate (PET), whose intrinsic ester carbonyl band obscures newly formed acid carbonyls in conventional infrared analyses. Here, we develop a µFTIR attenuated total reflection (µFTIR-ATR) imaging method combined with a fourth-derivative oxidation index (carbonyl ratio at 1701/1716 cm⁻¹) that resolves these overlapping bands and enables sensitive, quantitative evaluation of PET surface oxidation. The approach automates detection, identification, and oxidation analysis of particles down to ~2 µm. Laboratory UV irradiation experiments show a systematic increase in this derivative-based oxidation index with exposure dose. Application to ambient PET collected from Mt. Fuji, Tokyo, Osaka (Japan), and Siem Reap (Cambodia) reveals clear regional differences corresponding to local UV-A environments: PET from Siem Reap exhibited the highest oxidation, whereas particles from the Japanese sites showed moderate but variable aging. These results demonstrate that derivative-based µFTIR-ATR imaging provides a practical and highly sensitive tool for quantifying photo-oxidative degradation in fine AMPs and highlight the value of chemical-aging metrics for interpreting atmospheric processing and transport pathways. Full article

Background: 8-Hydroxyquinoline and phthalimide are two significant heterocyclic scaffolds in medicinal chemistry due to their pharmacological profiles. Hybridizing these pharmacophores and further modifying them via modified Mannich reactions provides a strategy to improve their physicochemical parameters and selectivity toward multidrug-resistant (MDR) cancer cells. Objectives: To synthesize a series of 8-hydroxyquinoline–phthalimide hybrids and their Mannich base derivatives and evaluate their cytotoxic activity and resistance-selective properties against sensitive Colo205 and resistant Colo320 cancer cell lines. Methods: Four hybrid compounds were synthesized by reacting 5-amino-8-hydroxyquinoline with different phthalic anhydride derivatives. Twelve fine-tuned derivatives were prepared by using the modified Mannich reaction. Cytotoxic activity was measured using the MTT assay, and relative resistance (RR) was calculated to determine selectivity toward the resistant cell line. P-glycoprotein (Pgp) ATPase activity was evaluated for the most active compounds. Results: All derivatives displayed cytotoxic activity, with higher potency toward the resistant Colo320 cell line. Compounds 2 and 4 showed the strongest activity against both cell lines (IC₅₀ down to 4.88 µM). Compounds 5, 8a, 9a, and 9c retained potent activity against Colo320 (IC₅₀ = 9.89–22.79 µM). Incorporating a CH₂–N group at position C7 substantially enhanced the selectivity for MDR cells. Compounds 9c, 9a, and 8a exhibited the highest selectivity, with RR values of 0.29, 0.33, and 0.35, respectively. Compounds 2, 4, 5, 8a, and 9a showed inhibitory effects on Pgp ATPase activity. Conclusion: The newly synthesized HQ–phthalimide hybrids represent promising candidates for targeting MDR in colorectal cancer, with Mannich modification enhancing the selectivity toward resistant cells. Full article

SARS-CoV-2 main protease (M^pro) is essential for viral polyprotein processing and represents a prime target for antiviral drug discovery. However, most available screening strategies rely on computational predictions or cell-free biochemical approaches that provide limited functional context and often require specialized instrumentation, while mammalian cell-based models remain costly and require high biosafety levels. Accordingly, there remains a shortage of simple, rapid, and biosafe functional screening tools suitable for early-stage prioritization of potential M^pro inhibitors, particularly those derived from natural sources and in urgent situations such as the COVID-19 pandemic. In this study, a bacterial colorimetric reporter assay was developed that directly links SARS-CoV-2 M^pro activity to β-galactosidase function in Escherichia coli. To the best of our knowledge, the developed assay represents the first bacterial colorimetric model for functional detection of SARS-CoV-2 M^pro inhibition based on a phenotypic readout. The assay enables the rapid visual detection of protease inhibition on X-gal-containing medium and provides a cost-effective and biosafe platform for prioritizing candidate inhibitors, under standard laboratory conditions, prior to further validation. Due to its bacterial expression context, this assay is intended for functional screening to provide the most promising candidate compounds and/or extracts for subsequent biochemical or mammalian cell-based validation; it is not intended to determine quantitative potency or to replace further validation approaches. It should be noted that the selective compound uptake in E. coli restricts the range of chemical compositions that can be evaluated using this method. Therefore, proof-of-concept application was demonstrated using pomegranate juice, a representative natural inhibitor source, rather than most currently known specific M^pro inhibitors. In addition, other plant-derived preparations, including rhubarb, grape, and red/black currant juices, were tested demonstrating the assay’s applicability to diverse natural matrices. Full article

Synucleinopathies, including Parkinson’s disease (PD), are neurodegenerative disorders characterized by aberrant aggregation of α-synuclein (α-syn), a presynaptic protein with an intrinsic disorder nature. The transition of soluble monomers into oligomeric and fibrillar species represents a key molecular event driving neuronal dysfunction and neurodegeneration. Emerging evidence suggests that nutraceuticals, bioactive compounds derived from dietary sources, can modulate α-syn aggregation at multiple conformational stages. Polyphenols, alkaloids, ginsenosides, and food-derived peptides interfere with α-syn structure and assembly, suppressing the formation of toxic oligomer species and promoting the clearance of misfolded assemblies. Despite this potential, clinical translational of nutraceuticals is currently limited by poor systemic bioavailability and restricted central nervous system penetration due to blood–brain barrier constraints, which have largely confined research to preclinical studies. In this context, this review summarizes current knowledge of nutraceutical interventions targeting the conformational landscape of α-syn and highlighting both direct and indirect molecular mechanisms with involved in aggregation-prone species. Furthermore, we critically examine key challenges related to bioavailability and clinical translation, focusing on advanced delivery systems and precision-based approaches to enhance neuroprotective efficacy and support the potential of nutraceuticals as novel or adjunctive therapeutic strategies for PD. Full article

For addressing the challenge that cross-interconnection of metal sheaths in long-distance high-voltage cables complicates the monitoring of cable insulation faults, it is proposed a fault diagnosis scheme based on resistive current, dielectric loss factor, and sheath current. The voltage and current signals at both ends of the cable are collected, as well as the current signals at the outlet of the grounding box and the transposition box. By establishing an equivalent model of the cross-connected cable, the calculation method for fault diagnosis is derived, and an implementation scheme for fault diagnosis is provided. The insulation monitoring method proposed in this paper is simulated and verified using MATLAB/Simulink software, with simulations conducted to investigate four typical faults: cable insulation fault, sheath open-circuit fault, transposition box immersion short-circuit fault, and cable intermediate-joint breakdown fault. The circuit model of the cross-connected unit is established in the laboratory to verify the method proposed in this paper. The results show that the simulation results are consistent with the test results, and the fault types can be correctly reflected, which verifies the correctness and effectiveness of the insulation monitoring method. Full article

Accurate staging of bladder cancer is critical for guiding clinical management, particularly the distinction between non–muscle-invasive (T1) and muscle-invasive (T2–T4) disease. Although MRI offers superior soft-tissue contrast, image interpretation remains operator-dependent and subject to inter-observer variability. This study proposes an automated deep learning framework for MRI-based bladder cancer staging to support standardized radiological interpretation. A sequential AI-based pipeline was developed, integrating hybrid tumor segmentation using YOLOv11 for lesion detection and DeepLabV3 for boundary refinement, followed by three deep learning classifiers (VGG19, ResNet50, and Vision Transformer) for MRI-based stage prediction. A total of 416 T2-weighted MRI images with radiology-derived stage labels (T1–T4) were included, with data augmentation applied during training. Model performance was evaluated using accuracy, precision, recall, F1-score, and multi-class AUC. Performance uncertainty was characterized using patient-level bootstrap confidence intervals under a fixed training and evaluation pipeline. All evaluated models demonstrated high and broadly comparable discriminative performance for MRI-based bladder cancer staging within the present dataset, with high point estimates of accuracy and AUC, particularly for differentiating non–muscle-invasive from muscle-invasive disease. Calibration analysis characterized the probabilistic behavior of predicted stage probabilities under the current experimental setting. The proposed framework demonstrates the feasibility of automated MRI-based bladder cancer staging derived from radiological reference labels and supports the potential of deep learning for standardizing and reproducing MRI-based staging procedures. Rather than serving as an independent clinical decision-support system, the framework is intended as a methodological and workflow-oriented tool for automated staging consistency. Further validation using multi-center datasets, patient-level data splitting prior to augmentation, pathology-confirmed reference standards, and explainable AI techniques is required to establish generalizability and clinical relevance. Full article

As the core thrust output component of electromagnetic drive systems, the Dual Three-Phase Linear Induction Motor (DT-LIM) places stringent requirements on the stability and reliability of its control system, and its sensorless control strategy has emerged as a research hotspot. However, as the motor operating frequency increases and the control carrier ratio decreases significantly, conventional algorithms lack sufficient capability to suppress process noise during model discretization, leading to a severe degradation of their observation performance. To address this issue, this paper proposes a Nonlinear Kalman Filter (NLKF) based on the Improved Euler (IE) discretization, which mitigates the model’s process noise at the source of discretization. Through stability and convergence analyses, the feasibility of the proposed algorithm and its advantages in terms of error convergence bounds are verified. The correctness of the theoretical derivations is confirmed through simulations. Furthermore, an experimental platform is established to compare the proposed algorithm with commonly used Kalman filters. A comprehensive analysis is conducted from the perspectives of online observation performance, closed-loop control performance, and computational complexity, thus verifying the proposed algorithm’s performance advantages. Full article

Background: Accurate detection of cervical lymph node metastases is a critical determinant of prognosis and treatment planning in head and neck squamous cell carcinoma (HNSCC). Although ultrasound-guided fine-needle aspiration biopsy (USgFNAB) is widely used as a minimally invasive diagnostic tool, its sensitivity for detecting occult metastases remains limited. Current preoperative staging modalities are further constrained by operator dependency and suboptimal specificity in early-stage disease. Integration of molecular diagnostics, particularly the analysis of long non-coding RNAs (lncRNAs), represents a promising strategy to enhance diagnostic accuracy. Objective: This review synthesizes the current evidence on lncRNA expression profiles in HNSCC, with an emphasis on their association with lymph node metastasis and potential application in FNAB-derived material for pre-treatment staging. Methods: A structured literature search was conducted, focusing on studies evaluating lncRNA expression profiles in HNSCC and their relevance to lymph node metastasis, with a particular focus on the feasibility of analysis of USgFNAB samples. Results: Multiple lncRNAs, including HOTAIR, MALAT1, UCA1, TUG1, AFAP1-AS1, H19, MEG3, and ADAMTS9-AS2, have been implicated in metastatic progression through their involvement in diverse mechanisms such as epithelial-to-mesenchymal transition, chromatin remodeling, angiogenesis, and pre-metastatic niche formation. Elevated expression of several of these transcripts correlates with adverse clinicopathological features, including advanced tumor stage, extranodal extension, and reduced survival. However, no studies have profiled lncRNA expression in matched primary tumors and metastatic lymph nodes, and transcriptomic analysis of FNAB samples remains largely unexplored in HNSCC. Conclusions: lncRNAs represent promising molecular biomarkers for enhancing the sensitivity and specificity of USgFNAB in detecting occult cervical metastases. Future research should prioritize paired tumor–node lncRNA profiling, validation of FNAB-based molecular assays, and integration of multi-omics data for predictive modeling. Overall, integrating lncRNA analysis into ultrasound-guided fine-needle aspiration biopsy may enhance the detection of occult nodal metastases in head and neck squamous cell carcinoma and support more accurate nodal staging in clinically node-negative patients. Full article

The widespread integration of inverter-based distributed generators (IIDGs) severely limits the adaptability of conventional three-step overcurrent protection in distribution networks (DNs). To address weak rural infrastructure and incomplete post-fault data, this paper proposes a dynamic adaptive current protection strategy for active distribution networks (ADNs) against two-phase short-circuit faults (TPSCFs), using local sequence components. First, we derive analytical expressions for positive/negative-sequence current/voltage at feeder outlet protection devices during TPSCFs, analyzing how the IIDG fault output affects these components. Based on this, an adaptive scheme is developed using only local measurements, with feeder head voltage/current sequence components as criteria. Leveraging line impedance and topology, the scheme ensures selective, accurate fault section identification under incomplete measurements, requiring only feeder head sequence data. A high-IIDG-penetration DN model is built in PSCAD/EMTDC, and TPSCFs under various conditions are simulated. Results show the scheme provides rapid, reliable full-line protection for TPSCFs in IIDG-penetrated ADNs, enhancing protection effectiveness. Full article

Emerging technologies offer cultural institutions opportunities to expand their audiences and make their content more accessible. Augmented Virtuality (AV), which integrates real-world content into virtual environments, shows particular potential. It enables the transmission of live or pre-recorded stage performances, such as concerts and theater productions, from the stage to virtual audiences via increasingly affordable head-mounted displays (HMDs). However, as AV remains under-researched, little is known about which recording features enable an immersive user experience while maintaining cost-efficiency—an essential requirement for resource-constrained cultural institutions. In this context, we investigate the influence of features of audio and video recordings on key dimensions of user experience in the use case of a real opera performance integrated into a virtual opera house. We conducted a 2 × 2 within-subjects study with 30 participants to measure the effects of 2D versus 3D videos and stereophonic versus spatial audio rendering on several key dimensions of user experience. The results show that spatial audio has a positive impact on Place Illusion, whereas video dimensionality had no significant effect. Recommendations for the design of AV applications are derived from study results, aiming at balancing immersive user experience and cost-efficiency for virtual cultural participation. Full article

Peroxisomes are multifunctional organelles that play essential roles in lipid metabolism, redox regulation, and cellular signaling. An expanding body of evidence implicates peroxisomal dysfunction as a key contributor to aging and age-related diseases. Aging is accompanied by progressive declines in key peroxisomal functions, including catalase activity, fatty acid β-oxidation, plasmalogen biosynthesis, and the metabolism of bile acids and docosahexaenoic acid, resulting in increased oxidative stress, lipid dysregulation, and alterations in membrane composition. Impaired pexophagy further exacerbates these defects by allowing the accumulation of damaged peroxisomes and compromising cellular homeostasis. Through extensive metabolic and signaling crosstalk with mitochondria, the endoplasmic reticulum, and lysosomes, peroxisomal dysfunction can propagate oxidative and metabolic disturbances throughout the cell. In addition, peroxisome-derived signaling molecules, such as hydrogen peroxide and bioactive lipids, link peroxisomal activity to cellular stress responses and organismal metabolic homeostasis. We propose that aging-associated impairments in peroxisomal protein import, redox regulation, and selective turnover progressively shift peroxisomes from adaptive metabolic signaling hubs toward sources of chronic oxidative and lipid stress. In this context, current studies highlight peroxisomal homeostasis as a potential determinant of healthy aging and point to peroxisomal pathways as emerging targets for intervention in age-related disease. Full article

Background/Objectives: Children and adolescents with intellectual disabilities (ID) have an elevated burden of obesity and cardiometabolic risk, yet factors associated with high blood pressure (BP) in this group remain insufficiently described. This study assessed the prevalence of hypertension (HTN) and isolated systolic hypertension (ISH) at a single visit and examined anthropometric and body composition correlates of elevated BP in children with ID. Methods: A cross-sectional study was conducted among 461 children and adolescents with ID aged 7–18 y attending special education schools in southeastern Poland. Anthropometric indicators (BMI, waist circumference [WC], hip circumference [HC], and waist-to-height ratio [WHtR]) and body composition parameters (BF%, MM%, FFM%, TBW%) were measured using standardized procedures. BP was assessed three times during one visit, and the average of the second and third readings was used. Receiver operating characteristic (ROC) analyses were used for exploratory assessment of discriminatory performance of anthropometric and body composition parameters, and multivariable logistic regression examined associations with elevated BP (HTN + ISH). Results: Overall, 13.9% of participants had HTN and 10.4% had ISH (combined prevalence: 24.3%). Abdominal obesity was present in 39.5% of participants, and elevated HC in 28.2%, both more common in girls. Higher BP categories were associated with greater WC, HC, BMI, and BF%, and lower MM%, FFM%, and TBW% (p < 0.0001). HC showed the highest discriminatory accuracy for HTN + ISH (AUC = 0.844), followed by MM%, BF%, and FFM%, whereas WHtR demonstrated limited discriminatory performance in ROC analyses. In multivariable models, WHtR ≥ 0.5 was associated with increased odds of elevated BP (OR = 4.25), whereas higher TBW% (≥55.38%) was inversely associated with elevated BP (OR = 0.17) in the total sample; similar patterns were observed in sex- and age-stratified analyses. Conclusions: Children with ID show a high prevalence of elevated BP at a single visit, including HTN-range and ISH-range values. Anthropometric indicators, particularly HC and WHtR, and BIA-derived body composition parameters reflecting higher fat mass and lower lean tissue proportion were associated with elevated BP. These exploratory findings suggest that simple anthropometric and body composition measures may help identify individuals who warrant further BP assessment, although longitudinal studies with repeated measurements are required before clinical application. Full article

Marine ecosystems represent a largely untapped reservoir of bioactive compounds with significant pharmacological potential. This study aimed to evaluate the therapeutic properties of ethanol extracts from four marine species: Padina australis, Spatoglossum asperum, Holothuria (Halodeima) atra, and Hypnea valentiae. Phytochemical screening, along with a comprehensive series of in vitro, in vivo, and in silico assays, was performed to evaluate the extracts’ pharmacological activities, including antioxidant potential (2,2-diphenyl-1-picrylhydrazyl assay), anti-inflammatory effect (carrageenan-induced paw edema method), analgesic activity (acetic acid-induced writhing and tail immersion tests), and anti-arthritic efficacy (protein denaturation assay). The extracts were found to be rich in flavonoids, tannins, alkaloids, saponins, glycosides, and phenolic compounds, which may underlie the observed bioactivities. In the acetic acid–induced writhing test, Hypnea valentiae at 400 mg/kg exhibited the highest peripheral analgesic activity, producing 82.51% inhibition of writhing (p < 0.001). In the tail immersion assay, Padina australis at doses of 200 and 400 mg/kg showed significant central analgesic effects, as evidenced by increased latency time and percentage of maximum possible effect (MPE). In the carrageenan-induced paw edema model, several treatment groups, including Padina australis, Hypnea valentiae, Spatoglossum asperum, and Holothuria atra, at both tested doses showed marked suppression of inflammation, with some groups achieving complete inhibition (100%; p < 0.001) at 120 min. The ethanol extract of Holothuria atra exhibited the strongest antioxidant and anti-arthritic activities, with an IC₅₀ value of 88.39 µg/mL in the DPPH assay and 81.35% inhibition of protein denaturation. Additionally, the compounds derived from the four marine species exhibited significant binding affinity to the selected target receptors, thereby validating the experimental findings. The marine species studied possess multifaceted pharmacological properties, supporting their potential as natural sources for developing therapeutic agents supporting the blue economy. Further studies are recommended to isolate active compounds and elucidate underlying mechanisms to support future drug development efforts. Full article

The physiological relevance of in vitro models is limited because conventional two-dimensional cell culture systems are unable to replicate the structural and functional complexity of native tissues. Extracellular matrix (ECM)-mimetic hydrogels have become important platforms for tissue engineering applications. This work developed hybrid hydrogels that mimic important biochemical and mechanical characteristics of cardiac tissue by combining decellularized bovine pericardium-derived (dBP) ECM, gellan gum (GG), and spermine (SPM). Although dBP offers tissue-specific biological cues, processing compromises its mechanical integrity. This limitation was overcome by adding GG, whose ionic gelation properties were optimized using DMEM and SPM. The hydrogels’ mechanical, biological, physicochemical, and structural characteristics were all evaluated. Under physiologically simulated conditions, the formulations showed quick gelation and long-term stability; scanning electron microscopy revealed an interconnected, ECM-like porous microarchitecture. While uniaxial compression testing provided Young’s modulus values comparable to native myocardium, rheological analysis revealed a concentration-dependent increase in storage modulus with increasing SPM content. H9C2 cardiomyoblasts were used in cytocompatibility studies to confirm that cell viability, morphology, and cytoskeletal organization were all preserved. All of these findings support the potential application of dBP−GG−SPM hydrogels in advanced in vitro cardiac models by showing that they successfully replicate important characteristics of cardiac ECM. Full article

The aim of this article is to identify and systematize the principal research directions in sustainable strategic management (SSM) at the intersection of eco-innovation and business performance. Despite the growing prominence of sustainability in management scholarship, systematic understanding of how SSM, eco-innovation, and business performance are connected in the academic literature remains limited. In particular, it is unclear whether this intersection constitutes a coherent research domain or instead reflects a set of loosely related and fragmented lines of inquiry. To address this gap, the study combines bibliometric analysis and science mapping of 181 Scopus-indexed publications (2006–2024) with a PRISMA-guided scoping review of five core papers that explicitly link SSM, eco-innovation, and business performance. VOSviewer was used to identify thematic clusters and structural gaps, including missing or weak linkages between eco-innovation and different dimensions of business performance. Building on these findings, the article proposes a dual-path conceptual model: (1) a mediated path in which eco-innovation functions as a transmission mechanism between SSM and multidimensional business performance, and (2) a direct path linking SSM to business performance without mediation. The model further distinguishes between internal organizational conditions, which predominantly support the direct path, and external business environment factors, which are critical in enabling the mediated path through eco-innovation. The main contributions are as follows: (a) a structured mapping of the SSM–eco-innovation research field and its emerging thematic architecture; and (b) a conceptual model specifying the dual role of eco-innovation in shaping business performance outcomes. The study also outlines implications for theory, managerial practice, and public policy, particularly in terms of how organizations and their environments influence the effectiveness of different strategic sustainability pathways. The proposed framework should be interpreted as an evidence-informed conceptual model derived from bibliometric patterns and focused qualitative synthesis, rather than as a statistically validated causal model. Full article