Search Results (4,516)

Astaxanthin (AST) is a potent carotenoid renowned for its exceptional antioxidant properties, which has attracted considerable scientific interest due to its broad spectrum of health benefits. This review comprehensively evaluates the therapeutic potential of AST in counteracting age-related decline, oxidative stress, and immune dysfunction, while also examining its beneficial effects on gut and skin health. Current evidence demonstrates that AST effectively mitigates oxidative stress and supports cellular health and longevity by neutralizing free radicals and upregulating endogenous antioxidant systems. In addition, AST modulates immune responses under conditions of immune dysfunction, thereby enhancing resilience against inflammatory disorders and infections. Emerging studies further indicate that AST promotes gut health by improving intestinal barrier integrity and maintaining a balanced gut microbiota, both of which are essential for systemic well-being. Moreover, its capacity to enhance skin elasticity and protect against ultraviolet-induced damage underscores its promising applications in cosmetic and dermatological products. This review highlights the urgent need for additional well-designed clinical trials to fully elucidate the underlying mechanisms, optimal bioavailability, dosage regimens, and long-term safety of AST. By integrating findings across multiple research domains, the present work provides a concise yet comprehensive overview of AST as a promising nutraceutical for promoting health, healthy aging, and the management of chronic diseases. Full article

Transcatheter aortic valve replacement (TAVR) has transformed the management of severe aortic stenosis and is now widely used across a broad spectrum of surgical risk. With expanding indications and increasing use in younger patients, contemporary practice increasingly emphasizes lifetime management of aortic valve disease, a shift further supported by recent developments including findings from the EARLY TAVR trial and the May 2025 U.S. Food and Drug Administration approval of TAVR for asymptomatic severe aortic stenosis. This narrative review summarizes recent developments in TAVR, including advances in device technology, procedural techniques, and patient selection. Focus is placed on the importance of optimal first valve selection, prevention of prosthesis–patient mismatch (PPM), and planning for future reintervention such as valve-in-valve (ViV) TAVR. Emerging procedural strategies including bioprosthetic valve fracture and leaflet modification techniques have expanded treatment options for patients at risk of elevated gradients or coronary obstruction. The review also highlights evolving approaches to TAVR in complex clinical scenarios and discusses future directions in device design and imaging-based procedural planning. As TAVR continues to evolve, careful procedural planning and multidisciplinary heart team collaboration remain essential to optimizing long-term outcomes. Full article

Background/Objectives: The current study was designed to identify the underlying genetic causes of congenital stationary night blindness (CSNB) in the indigenous consanguineous families from the Southern Punjab region of Pakistan, a population where the inherited retinal disorders are relatively common. Methods: A detailed questionnaire and medical examination were done to check the presence of CSNB in the affected individuals of the enrolled families. Whole-exome sequencing (WES) was performed to identify the pathogenic variants, followed by segregation analyses to confirm the segregation of the identified variants with the disease phenotype in the available affected individuals of the families. Results: We identified two novel and three known pathogenic variants in SAG, GRK1, TRPM1, SLC24A1, and GPR179, having established roles in CSNB. Two novel variants, NM_001252020.1 (p.Gly1020Arg) and NM_001004334.3 (p.Trp508Ter), were identified, and their segregation was confirmed in two families, PKIURP102 and PKIURP564, respectively. NM_002929.3 (p.Arg19Ter) and NM_001301032.1 (p.Phe538CysfsTer23) were the reported variants identified in PKIURP17 and PKIURP528 families, respectively. NM_000541.5 (p.Glu306Ter) was identified in two independent families, PKIURP552 and PKIURP565. Conclusions: Identification of five pathogenic variants in five different genes shows the genetic heterogeneity of CSNB in Pakistani patients. Our findings also expand the mutational spectrum of CSNB in the Pakistani population and may help in the identification of mutational hotspots and may help in the genetic diagnosis of CSNB in consanguineous populations. Full article

The dielectric response provides an integral description of polarization mechanisms across frequency ranges and constitutes a key physical basis for understanding ferroelectric behavior. Here, we systematically investigate the broadband dielectric response of Group-II metal oxide (BeO, MgO, CaO, ZnO, and CdO) monolayers using first-principles calculation. In the low-frequency regime, ionic polarization governs the dielectric response. A distinctive feature is the LO–TO degeneracy at the Γ point accompanied by a V-shaped nonanalytic LO phonon dispersion. d-state hybridization increases with the metal atomic number, resulting in higher Born effective charge, which works together with phonon softening, reduced mass and unit cell area to significantly strengthen the ionic dielectric contribution. The quasiparticle band gap decreases with the metal atomic number, driving redshifts of the dielectric function and wide band optical response from the deep-ultraviolet to the near-infrared. Particularly, CdO exhibits the strongest electronic polarization, with an optical dielectric constant of 2.68 and a static refractive index of 1.64. This work establishes a complete dielectric spectrum from ionic to electronic polarization, providing theoretical guidance for polarization engineering and design of two-dimensional ferroelectric devices. Full article

Tuberculosis (TB) remains a leading cause of infectious mortality worldwide, reflecting persistent gaps in diagnosis, risk stratification, and treatment monitoring. Host RNA transcriptomic signatures have emerged as promising tools for capturing dynamic immune responses across the TB disease spectrum. Among these, the six-gene RISK6 signature has attracted attention due to its parsimonious design and potential for clinical translation. This review provides a clinically oriented synthesis of current evidence on host transcriptomic biomarkers, with a particular focus on the application of RISK6 in diagnosis, prediction of disease progression, and treatment monitoring. Available data suggest that RISK6 demonstrates promising but context-dependent diagnostic performance and represents a versatile host-response biomarker across multiple clinical applications. However, variability across populations and the limited evidence in multidrug-resistant TB remain important constraints. In practice, RISK6 is unlikely to function optimally as a standalone biomarker. Its clinical value appears greater when interpreted within integrated frameworks that combine transcriptomic, microbiological, and clinical data. Further validation in diverse populations and real-world settings will be essential to support meaningful clinical implementation. Full article

We evaluated the antimicrobial and antioxidant capabilities of a bacteriocin purified from a recently identified marine Lactococcus lactis (L. lactis) NAN6399 strain, a lactic acid bacterium recovered from Mediterranean coastal waters near Alexandria, Egypt, and identified by combined API 50 CHL phenotypic profiling and 16S rRNA gene sequencing. Bacteriocin purification was achieved by sequential ammonium sulfate precipitation and reverse-phase high-performance liquid chromatography (RP-HPLC). The purified bioactive fraction had an approximate molecular weight of 20 kDa by SDS-PAGE and a 106-amino-acid N-terminal sequence that, upon BLAST alignment, returned 98.1% overall identity to the Lactococcin 972 family bacteriocin AAK06118.1 from L. lactis IL1403, with divergence confined exclusively to the terminal two C-terminal residues. This sequence is structurally and functionally distinct from canonical Lcn972 (L. lactis IPLA 972): the two peptides share an identical 25-residue signal peptide but diverge entirely in their mature bioactive domains, which exhibit only 9.1% sequence identity. Canonical Lcn972 operates through Lipid II-mediated septum disruption and inhibits only Lactococcus species; the NAN6399 peptide, correctly designated as a novel member of the Lcn972-like peptide family, demonstrated broad-spectrum antimicrobial efficacy against multiple indicator organisms (Staphylococcus aureus, Salmonella typhimurium, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Enterococcus faecalis), producing inhibition zones of up to 30 mm and minimum inhibitory concentration (MIC) values as low as 1.25 μg/mL against S. aureus. Antioxidant capacity was assessed using the DPPH radical scavenging assay, with the purified preparation achieving 73.14 ± 0.34% inhibition. Collectively, these data establish L. lactis NAN6399 as the producer of a bifunctional Lcn972-family bacteriocin with both antimicrobial and antioxidant potential, provide the first experimental characterization of the antimicrobial activity of this Lcn972-family branch, and highlight marine LAB as a productive reservoir for novel bioactive peptide discovery. Full article

To address the demand for underwater acoustic detection with hydrostatic pressure resistance, this paper proposes a fiber-optic Fabry–Perot (F-P) underwater acoustic sensor based on micro-electromechanical system (MEMS) technology. According to the F-P interference principle, the diaphragm deforms under acoustic pressure, inducing variations in the F-P cavity length which modulate the interference spectrum and enable the measurement of underwater acoustic signals. A sensing diaphragm with a composite structure consisting of a central boss and a micro-hole array is designed, which improves the optical signal quality while reducing the influence of the pressure difference between the inner and outer surfaces of the diaphragm on sensor operation. MEMS fabrication, computer numerical control (CNC) machining, and laser fusion splicing technologies are employed to achieve batch fabrication of the sensing units and adhesive-free integration of the sensor. Experimental results show that the proposed sensor exhibits a flat frequency response within ±1.5 dB over the range of 1 kHz to 10 kHz, with an average signal-to-noise ratio (SNR) of 86.35 dB. The sensitivity reaches −181.79 dB re 1 rad/μPa at 10 kHz, with a maximum nonlinearity of 0.48% F.S., a repeatability error of 0.15% F.S. and a dynamic range of 100.83 dB. The proposed sensor features miniaturization, high consistency, hydrostatic pressure self-balancing capability, and immunity to electromagnetic interference, providing a solid foundation for hydrostatic-pressure-resistant underwater acoustic measurements in deep-sea environments. Full article

Autism spectrum disorder (ASD) is highly heterogeneous in symptom onset and severity, comorbidities, and treatment responsiveness, challenging the notion of a single pathogenic mechanism. Increasing evidence indicates that some individuals with ASD exhibit prominent peripheral physiological alterations, including gastrointestinal (GI) dysfunction, gut microbial dysbiosis, immune imbalance, oxidative stress, and mitochondrial/energy metabolic vulnerability. In this context, gut-derived metabolites—particularly short-chain fatty acids (SCFAs)—have emerged as plausible modulators of the neurodevelopmental milieu through the expanded gut–immune–metabolic–brain axis. This review synthesizes: (i) SCFAs’ biogenesis and physiological roles, (ii) context- and developmental stage-dependent effects, (iii) the clinical heterogeneity of reported microbiome and SCFA alterations in ASD, and (iv) propionate as a frequently discussed candidate signal and the interpretive boundaries of preclinical evidence. Human studies show substantial inter-study variability in SCFA alterations (increases, decreases, or no differences), influenced by factors such as sample type (stool vs. blood), GI symptoms, diet, medication exposure, and analytical variability. Accordingly, SCFAs should not be treated as universal ASD biomarkers but rather as context-dependent metabolic signals relevant under specific clinical and biological conditions. Building on this premise, we propose the conceptual framework of “metabolic ASD” representing a metabolically informed dimension of biological variability in which peripheral metabolic–immune perturbations may contribute to neurodevelopmental vulnerability. To avoid premature causal claims, we outline design requirements for future research, including stratified study designs, longitudinal cohorts, and integrative multi-layer analyses. Ultimately, metabolic ASD should be positioned as a testable precision medicine research framework rather than a universal etiological model. Full article

This paper develops a reliability analysis model for a class of computer systems composed of hardware and software in series, considering a repairman taking multiple vacations. The system follows a series failure rule: hardware can be repaired to be as good as new after failure; software undergoes minor repairs to maintain operability after the first $N-1$ failures with an increasing failure rate, and is overhauled to be as good as new with cycle reset after the N-th failure. Based on the principle of probability conservation and the supplementary variable method, the state probability evolution equations of the system are derived. A Banach space is constructed, and a linear operator is defined, whose denseness, dissipativity, and closedness are verified. It has been proven that the operator generates a positive contractive $C_0$-semigroup, thus rigorously establishing the well-posedness of the model and the existence of a unique positive dynamic solution. Further spectral analysis verifies that zero belongs to the continuous spectrum rather than the point spectrum of the system operator.This indicates that the investigated system admits no time-invariant constant steady-state probability distribution,and only presents slowly decaying quasi-stationary dynamic behavior. The results can provide theoretical support for the reliability design and maintenance strategy optimization of hardware–software series repairable systems. Full article

The International Civil Aviation Organization (ICAO) sets strict limits for aircraft ramp noise, a key source of which is Auxiliary Power Unit (APU) inlet noise. This paper presents a systematic and computationally efficient design methodology for APU inlet mufflers. The high-frequency noise necessitates validating a single-degree-of-freedom liner impedance model up to 10,000 Hz. The core innovation overcomes prohibitive full-passage simulation costs (days) by optimally selecting attenuation center frequencies from the source spectrum and implementing an axially segmented design. This approach enables efficient, targeted optimization (minutes per case) and leverages acoustic mode scattering at segment interfaces to enhance overall attenuation. The design is verified via high-fidelity, full-flow-path simulation. Experimental validation under various operating conditions shows good agreement with predictions, achieving approximately 9 dB reduction in overall A-weighted Sound Power Level (OASPL) with consistent performance. The results demonstrate the feasibility and effectiveness of the proposed rapid, precise, and efficient design framework. Full article

Photodetectors have undergone widespread, gradual application. Correlation detectors with varying properties are used in diverse fields. This review systematically summarizes the principles, properties, and applications of various photoelectric detectors reported in the past five years, compares their similarities and differences, and further discusses their respective advantages and disadvantages, applicable scenarios, and development prospects. The review covers self-powered detectors, which are very convenient and widely used in consumer electronics and portable wearable devices, and discusses the structural design and photoelectric performance of devices based on P–N junctions, perovskites, silicon–polymer hybrid composites, graphene, hybrid graphene/PbS quantum dot systems, and other novel material architectures. Compound photoelectric detectors enable multifunctional integration and intellectualization. At the same time, their high sensitivity and broad-spectrum response can expand the detection wavelength range to cover the ultraviolet, visible, and infrared bands and enhance the detection of weak optical signals. Finally, this review summarizes current challenges, including cumbersome fabrication processes, susceptibility of detection stability to environmental interference, and limited functionality, and focuses on recent advances in various photodetectors, where breakthroughs are expected. Full article

Damping modeling significantly influences the numerical seismic response of buildings, something that, despite being repeatedly emphasized in earthquake engineering research, is still overlooked even by seismic codes. It is a fact that, for simplification and ease of application, modern seismic design provisions assume damping for buildings entirely composed of a single material, e.g., reinforced concrete or structural steel. The current codes offer no guidance on damping assumptions for so-called mixed buildings comprising a lower part (stories) of reinforced concrete and an upper part (stories) of structural steel. Despite the growing use of mixed reinforced concrete-structural steel buildings, damping modeling of their seismic response remains almost unexplored. This study aims to contribute to this field by investigating the effect of different damping models on the elastic and inelastic seismic response of realistic three-dimensional mixed buildings. Modal response spectrum and time-history analyses served for this purpose. Key seismic response parameters, including interstory drift ratios, floor accelerations, and base shear demands, are extracted and systematically compared for the examined damping models. The results highlight the sensitivity of computed seismic demands to the assumed damping model. Guidance on selecting a damping model for the seismic analysis of mixed reinforced concrete-structural steel buildings is provided. Full article

To improve the visible-light-driven photocatalytic degradation efficiency of g-C₃N₄-based photocatalysts toward organic pollutants, a MoS₂/g-C₃N₄ composite precursor was employed in this work, and the phase composition and defect environment of Mo species were regulated by post-annealing under air and N₂ atmospheres, respectively, thereby constructing Mo-based/g-C₃N₄ (MCN) composites with distinct structural evolution characteristics. The results showed that the photocatalytic activity of the as-sonicated MCN composite toward methylene blue (MB) was only moderately improved, among which the 15% loading sample exhibited the best performance with a degradation efficiency of about 42.0% within 60 min. In contrast, annealing at 400 °C under N₂ resulted in only a slight activity change, whereas the sample treated at 400 °C in air (Air-15% MCN) achieved an MB degradation efficiency of 99.9% within 60 min, together with a much higher pseudo-first-order reaction rate constant than that of the air-treated sample at a lower temperature. XRD, FT-IR and XPS analyses revealed that air annealing induced the conversion of MoS₂ into highly crystalline MoO₃ (or MoO₃₋_x), leading to the formation of a reconstructed MoO₃₋_x/g-C₃N₄ composite interface. Meanwhile, the increased high-binding-energy component in the O 1s spectrum and the EPR signal around g ≈ 2.00 further suggested the presence of more abundant defect-related centers in the air-treated sample. Although Air-15% MCN possessed a lower specific surface area than the untreated and N₂-treated samples, it displayed enhanced visible-light absorption, higher transient photocurrent response, lower interfacial charge-transfer resistance, and accelerated carrier dynamics, indicating that the activity enhancement mainly originated from atmosphere-induced phase transformation, interfacial reconstruction, defect-related active centers, and improved charge separation/transfer, rather than from the surface area effect. Based on the above results, a possible interfacial charge-transfer pathway is tentatively proposed for the g-C₃N₄/MoO₃₋_x interface formed after air treatment, which contributes to the efficient utilization of photogenerated carriers and the rapid degradation of MB. This work demonstrates that atmosphere-induced phase transformation is a simple and effective strategy for regulating the structure and photocatalytic performance of Mo-based/g-C₃N₄ composites, and provides useful guidance for the design of efficient visible-light photocatalysts. Full article

Forest, shrubland, and grassland exhibit highly overlapping characteristics, and single-modal remote sensing data cannot simultaneously capture both spectral and structural information. Moreover, multimodal fusion learning of optical and SAR data faces challenges such as the lack of high-quality samples and difficulties in effective cross-modal feature fusion. Therefore, a high-resolution multimodal remote sensing feature dataset (GF23FSG) is constructed for the fine classification of forest, shrubland, and grassland, and a Cross-modal Adaptive Structure Fusion Network (CASFNet) is proposed. In response to the feature heterogeneity of optical and SAR, a cross-modal adaptive fusion module based on spatial alignment and a dynamic weight allocation strategy is proposed, which effectively enhances the learning of spectral–spectrum heterogeneous features. In addition, a multi-level auxiliary supervision mechanism is introduced to strengthen feature representation learning. Gradient constraints are further imposed on deep-level features to improve the model’s ability to capture and learn deep cross-modal representations, thereby effectively mitigating representation degradation during the feature fusion process. Experiments on the self-constructed GF23FSG dataset and the publicly available SEN12MS dataset achieve OA of 77.38% and 71.84%, respectively, demonstrating superior classification performance compared with SOTA methods. In addition, comparative analysis with public land cover products and field samples further confirm the reliability and generalization performance of the proposed dataset and model for the fine classification of forest, shrubland, and grassland. This study provides a new solution for the fine classification of forest, shrubland, and grassland from multimodal remote sensing images from the perspectives of dataset construction and methodological design. Full article

Cucurbit crops—including cucumber (Cucumis sativus), watermelon (Citrullus lanatus), and melon (Cucumis melo)—are of major economic and nutritional importance worldwide. Yet their productivity and quality are severely compromised by foliar fungal diseases, particularly powdery mildew (PM), downy mildew (DM), and target leaf spot (TLS). While PM and DM have been extensively studied, TLS has emerged as an increasingly prevalent and damaging disease in key production regions, yet it remains comparatively understudied—especially with respect to its molecular basis and comparative pathobiology relative to PM and DM. Current reliance on chemical fungicides is hampered by escalating pathogen resistance and concerns over residual toxicity, whereas conventional breeding approaches face inherent limitations in pyramiding durable, broad-spectrum resistance against multiple pathogens. In this context, cucumber has emerged as a pivotal model species for dissecting foliar disease resistance mechanisms in cucurbits, supported by a high-quality reference genome, extensive resequencing datasets, diverse germplasm collections, and an efficient Agrobacterium-mediated transformation system. Despite these advantages, existing reviews predominantly address PM or DM resistance in isolation; comprehensive syntheses integrating TLS resistance advances—and critically, cross-disease comparisons of genetic architecture, transcriptional reprogramming, and defense signaling—are notably scarce. Furthermore, the translational pipeline—from gene discovery and functional validation to deployment in marker-assisted or genome-edited breeding—lacks systematic evaluation. Here, we provide a focused, cucumber-centered review that (i) synthesizes recent progress in mapping QTLs and GWAS loci, and characterizing key resistance-associated gene families (such as NLRs, RLKs, PR genes) conferring resistance to PM, DM, and TLS; (ii) integrates transcriptomic, epigenomic, and proteomic evidence to delineate conserved versus pathogen-specific host responses; (iii) highlights breakthroughs and unresolved questions in TLS resistance research, including the roles of novel susceptibility factors and non-canonical immune regulators; and (iv) critically assesses bottlenecks in translating resistance genes into practical breeding outcomes—such as linkage drag, functional redundancy, and genotype-by-environment interactions—and proposes empirically grounded strategies for accelerating molecular design of multi-disease-resistant cultivars. Collectively, this review aims to bridge fundamental insights with applied breeding goals, offering a conceptual and strategic framework for integrated management of foliar fungal diseases and the development of durable, broad-spectrum resistance in cucurbits. Full article