Search Results (85)

This study systematically investigates the effects of aging treatment (AT) on the microstructure and properties of Cr/DLC coatings deposited via cathodic arc ion plating onto the surface of ECAP-7075 aluminum alloy. Utilizing a comprehensive approach combining performance tests (nanoindentation, nanoscratch testing, dynamic polarization analysis) with characterization tests (scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy), the synergistic effects of equal channel angular pressing (ECAP) and aging treatment(AT) were elucidated. The results demonstrate that the combined ECAP and AT significantly enhance the coating’s performance. Specifically, AT promotes the precipitation of η’ phase within the 7075 aluminum alloy substrate, increases the size of Cr₇C₃ crystallites in the Cr-based interlayer, improves the crystallinity of the Cr₇C₃ phase on the (060) or (242) crystal planes, and elevates the sp³-C/sp²-C ratio in the diamond-like carbon(DLC) top layer, leading to partial healing of defects and a denser overall coating structure. These microstructural transformations, induced by AT, result in substantial improvements in the mechanical properties (hardness reaching 5.2 GPa, bond strength achieving 15.1 N) and corrosion resistance (corrosion potential increasing to -0.698 V) of the Cr/DLC-coated ECAP-7075 aluminum alloy. This enhanced combination of properties makes these coatings particularly well-suited for high-performance aerospace components requiring both wear resistance and corrosion protection in demanding environments. Full article

Glycolipids are structurally diverse amphiphilic molecules with potential as non-petrochemical-derived bioproducts, including surfactants, emulsifiers, and antioxidants. The different bioactivities associated with this range of glycolipid structures also present opportunities for dietary supplements, cosmetics, and pharmaceuticals. Marine glycolipids are underexplored due to challenges with purification and structural characterisation. Analytical approaches enabling efficient sample purification, isolation, and identification of target glycolipids are crucial to determining the bioactivity and functions of organisms such as shellfish and seaweed. This review summarises advances in analytical methods applicable to marine glycolipids, including extraction and enrichment methods tailored to specific subclasses. Thin-layer chromatography (TLC)-based rapid detection techniques developed for specific subclasses in complex biological samples are discussed, alongside structure identification methods based on liquid chromatography (LC)–electrospray ionisation (ESI)–tandem mass spectrometry (MS/MS). Hydrophilic interaction liquid chromatography (HILIC), reverse-phase liquid chromatography (RPLC), and supercritical fluid chromatography (SFC) coupled with MS detection are reviewed for their application to glycolipids. The application of two-dimensional liquid chromatography (2D-LC) and advanced MS-based approaches that facilitate both the rapid resolution and comprehensive characterisation of molecular species are also reviewed. Full article

Daphne odora is an evergreen shrub belonging to the Thymelaeaceae family that is widely cultivated as an ornamental garden plant. Its roots, leaves, and flowers have traditionally been used in Chinese medicine to treat pain, skin diseases, and rheumatism. While previous phytochemical studies have reported the presence of phenols, coumarins, biflavonoids, lignans, and daphnane diterpenoids in D. odora, its flowers remain largely unexplored. In the present study, the first comprehensive investigation of daphnane diterpenoids contained in the flower buds and blooming flowers of D. odora was conducted using ultra-high-performance liquid chromatography coupled with Q-Exactive-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Exactive-Orbitrap MS). A total of 30 daphnane diterpenoids were identified, including 12 previously unreported compounds, through detailed analysis of their retention times and MS/MS fragmentation patterns. Comparative profiling revealed that flower buds contained a higher abundance and greater diversity of daphnane diterpenoids than flowers. Furthermore, LC–MS-guided isolation enabled the purification of a novel compound, daphneodorin I (16), and its structure was elucidated through extensive physicochemical and spectroscopic analyses. Compound 16 represents the first daphnane diterpenoid with a Z-configured phenolic acyl moiety isolated from plants of the Thymelaeaceae family. Full article

Background: In recent decades, dermatological diagnostics have undergone a profound transformation, driven by the integration of new technologies alongside traditional methods. Classic techniques such as the Tzanck smear, potassium hydroxide (KOH) preparation, and Wood’s lamp examination remain fundamental in everyday clinical practice due to their simplicity, speed, and accessibility. At the same time, the development of non-invasive imaging technologies and the application of artificial intelligence (AI) have opened new frontiers in the early detection and monitoring of both neoplastic and inflammatory skin diseases. Methods: This review aims to provide a comprehensive overview of how conventional and emerging diagnostic tools can be integrated into dermatologic practice. Results: We examined a broad spectrum of diagnostic methods currently used in dermatology, ranging from traditional techniques to advanced approaches such as digital dermoscopy, reflectance confocal microscopy (RCM), optical coherence tomography (OCT), line-field confocal OCT (LC-OCT), 3D total body imaging systems with AI integration, mobile applications, electrical impedance spectroscopy (EIS), and multispectral imaging. Each method is discussed in terms of diagnostic accuracy, clinical applications, and potential limitations. While traditional methods continue to play a crucial role—especially in resource-limited settings or for immediate bedside decision-making—modern tools significantly enhance diagnostic precision. Dermoscopy and its digital evolution have improved the accuracy of melanoma and basal cell carcinoma detection. RCM and LC-OCT allow near-histological visualization of skin structures, reducing the need for invasive procedures. AI-powered platforms support lesion tracking and risk stratification, though their routine implementation requires further clinical validation and regulatory oversight. Tools like EIS and multispectral imaging may offer additional value in diagnostically challenging cases. An effective diagnostic approach in dermatology should rely on a thoughtful combination of methods, selected based on clinical suspicion and guided by Bayesian reasoning. Conclusions: Rather than replacing traditional tools, advanced technologies should complement them—optimizing diagnostic accuracy, improving patient outcomes, and supporting more individualized, evidence-based care. Full article

This paper addresses the challenges encountered by grid-connected photovoltaic (PV) systems, including the stochastic behavior of the system, harmonic distortion, and variations in grid impedance. To this end, an in-depth technical and pedagogical analysis of three linear multivariable current control strategies is performed: proportional-integral (PI), proportional-resonant (PR), and deadbeat (DB). The study contributes to theoretical formulations, detailed system modeling, and controller tuning procedures, promoting a comprehensive understanding of their structures and performance. The strategies are investigated and compared in both the rotating ($dq$) and stationary ($\alpha \beta$) reference frames, offering a broad perspective on system behavior under various operating conditions. Additionally, an in-depth analysis of the PR controller is presented, highlighting its potential to regulate both positive- and negative-sequence components. This enables the development of more effective and robust tuning methodologies for steady-state and dynamic scenarios. The evaluation is conducted under three main conditions: steady-state operation, transient response to input power variations, and robustness analysis in the presence of grid parameter changes. The study examines the impact of each controller on the total harmonic distortion (THD) of the injected current, as well as on system stability margins and dynamic performance. Practical aspects that are often overlooked are also addressed, such as the modeling of the inverter and photovoltaic generator, the implementation of space vector pulse-width modulation (SVPWM), and the influence of the output LC filter capacitor. The control structures under analysis are validated through numerical simulations performed in MatLab^® software (R2021b) using dedicated computational routines, enabling the identification of strategies that enhance performance and ensure compliance of grid-connected photovoltaic systems. Full article

Fibrocapsa japonica (Raphidophyceae) is a cosmopolitan species frequently associated with harmful algal blooms (HABs) and fish mortality events, representing a potential threat to aquaculture and coastal ecosystems. This study provides the first comprehensive morphological, phylogenetic, pigmentary, and toxicological characterization of F. japonica strains isolated from Argentina. Light and transmission electron microscopy confirmed key diagnostic features of the species, including anterior flagella and the conspicuous group of mucocyst in the posterior region. Phylogenetic analysis based on the LSU rDNA D1–D2 region revealed monophyletic relationships with strains from geographically distant regions. Pigment analysis by HPLC identified chlorophyll-a (62.3 pg cell⁻¹) and fucoxanthin (38.4 pg cell⁻¹) as the main dominant pigments. Cytotoxicity assays using RTgill-W1 cells exposed for 2 h to culture supernatants and intracellular extracts showed strain-specific effects. The most toxic strain (LPCc049) reduced gill cell viability down to 53% in the supernatant exposure, while LC₅₀ values ranged from 1.6 × 10⁴ to 4.7 × 10⁵ cells mL⁻¹, depending directly on the strain and treatment type. No brevetoxins (PbTx-1, -2, -3, -6, -7, -8, -9, -10, BTX-B1 and BTX-B2) were detected by LC–MS/MS, suggesting that the cytotoxicity may be linked to the production of reactive oxygen species (ROS), polyunsaturated fatty acids (PUFAs), or hemolytic compounds, as previously hypothesized in the literature. These findings offer novel insights into the toxic potential of F. japonica in South America and underscore the need for further research to elucidate the mechanisms underlying its ichthyotoxic effect. Full article

Sitagliptin is an orally bioavailable selective DPP4 inhibitor that reduces blood glucose levels without significant increases in hypoglycemia. The aim of this study was to design and validate an innovative, rapid, and highly sensitive LC–MS/MS assay for the precise measurement of sitagliptin concentrations in human plasma. This analytical method, utilizing sitagliptin-d4 as the internal standard, is performed using only 100 μL of plasma and a liquid–liquid extraction procedure based on methyl tert-butyl ether (MTBE). Chromatographic separation is expertly achieved with a Kinetex^® C18 column under isocratic elution, employing a perfect 1:1 blend of 5 mM ammonium acetate (with 0.04% formic acid) and acetonitrile, and maintaining an efficient flow rate of 0.2 mL/min. Detection occurs in positive ionization mode through multiple reaction monitoring, precisely targeting transitions of m/z 408.2 → 193.0 for sitagliptin and 412.2 → 239.1 for the IS. The total runtime of this assay is under 2 min. Comprehensive validation in line with MFDS and FDA criteria demonstrates outstanding linearity (5–1000 ng/mL, r² > 0.998), alongside impressive levels of accuracy, precision, recovery and sample stability. Due to its minimal sample requirement and high-throughput capability, the validated approach is highly appropriate for pharmacokinetic and bioequivalence assessments involving sitagliptin. Full article

Tonsils are secondary lymphoid organs that play a crucial role in the immunological response, with B cells being a major component involved in both innate and adaptive immunity. Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome and obstructive sleep apnea syndrome (OSAS) are both common pediatric conditions involving tonsillar pathology. In both syndromes, the molecular pathways dysregulated in tonsillar B cells are still to be understood. The study aimed to unravel and compare the proteomic profiles of tonsillar CD19+ B cells isolated from pediatric patients with PFAPA (n = 6) and OSAS (n = 6) to identify disease-specific molecular signatures. B cells were isolated from the tonsillar tissue using magnetic microbeads (with a purity of 93.50%). Proteomic analysis was performed by nanoLC-MS/MS with both data-dependent (DDA) and data-independent acquisition (DIA) methods, followed by comprehensive bioinformatic analysis. By merging DDA and DIA datasets, a total of 18.078 unique proteins were identified. Differential expression analysis revealed 83 proteins increased and 49 proteins decreased in OSAS B cells compared to PFAPA B cells (fold change ≥ 1.5 or ≤0.6, p < 0.05). Distinct pathway enrichments were highlighted, including alterations in the regulation of PTEN gene transcription, circadian gene expression, inflammasome pathways (IPAF and AIM2), and the metabolism of angiotensinogen to angiotensin. Specific proteins such as p53, Hdac3, RPTOR, MED1, Caspase-1, Cathepsin D, Chymase, and TLR2 (validated by WB) were shown to be differentially expressed. These findings reveal distinct proteomic signatures in tonsillar B cells from patients with PFAPA and OSAS, offering novel insights into the pathophysiology and potential avenues for biomarker discovery. Full article

Aloysia triphylla is widely used in traditional medicine from Peru for its sedative, digestive and anti-inflammatory properties. However, comprehensive studies on the biological activities of its essential oil (EO), particularly from Peruvian sources, remain limited. This study aimed to analyze the chemical composition and enantiomeric profile of A. triphylla EO and evaluate its antibacterial, antioxidant, anticholinesterase, and cytotoxic activities. The EO was obtained by steam distillation and analyzed using gas chromatography–mass spectrometry (GC-MS). A total of 62 compounds were identified, with (E)-caryophyllene (16.80%), β-pinene (9.96%), and germacrene D (10.00%) being the major components. Enantiomeric analysis revealed specific chiral signatures, including (−)-α-pinene, (+)-limonene, and (R)-(−)-linalool. The EO exhibited significant antibacterial activity, particularly against Bacillus subtilis (MIC = 5 µg/mL), and weak antioxidant activity (IC₅₀ = 7720 and 4648 µg/mL for DPPH and ABTS, respectively). Additionally, the EO demonstrated moderate acetylcholinesterase inhibition (IC₅₀ = 87.8 µg/mL) and cytotoxicity in the Artemia salina assay (LC₅₀ = 964 µg/mL). These findings suggest that A. triphylla EO possesses promising bioactivities with potential applications in pharmaceutical and cosmetic fields. Full article

Coordinating vehicle handling stability and energy consumption remains a key challenge for distributed driving electric vehicles (DDEVs). In this paper, a hierarchical torque vectoring control strategy is proposed to address this issue. First, a tire road friction coefficient (TRFC) estimator based on the fusion of vision and dynamic is developed to accurately and promptly obtain the TRFC in the upper layer. Second, a direct yaw moment control (DYC) strategy based on the adaptive model predictive control (MPC) is designed to ensure vehicle stability in the middle layer, where tire cornering stiffness is updated dynamically based on the estimated TRFC. Then, the lower layer develops the torque vectoring allocation controller, which comprehensively considers handling stability and energy consumption and distributes the driving torques among the wheels. The weight between stability and economy is coordinated according to the stability boundaries derived from an extended phase-plane correlated with the TRFC. Finally, Hardware-in-the-Loop (HIL) simulations are conducted to validate the effectiveness of the proposed strategy. The results demonstrate that compared with the conventional stability torque distribution strategy, the proposed control strategy not only reduces the RMSE of sideslip angle by 44.88% but also decreases the motor power consumption by 24.45% under DLC conditions, which indicates that the proposed method can significantly enhance vehicle handling stability while reducing energy consumption. Full article

Background/Objectives: This study explores the bioactive potential of Bovistella utriformis biomass and its polysaccharides (PsBu) through comprehensive biochemical and bioactivity analyses, focusing on their antioxidant, cytotoxic, and antihyperglycemic properties. Methods: Elemental analysis determined the biomass’s chemical composition. Antioxidant activity was assessed using ABTS and DPPH assays. Monosaccharide composition was analyzed via gas chromatography-mass spectrometry (GC-MS). In vitro cytotoxicity assays were conducted on cancer and normal cell lines to determine IC₅₀ values and selectivity indices (SI). Zebrafish embryo toxicity was evaluated for teratogenic effects, and an in vivo antihyperglycemic study was performed in diabetic rat models. Results: The biomass exhibited high carbon content (around 41%) and nitrogen levels, with a balanced C/N ratio nearing 5. Protein content exceeded 50%, alongside significant carbohydrate, fiber, and ash levels. Antioxidant assays revealed inhibition rates of approximately 89% (ABTS) and 64% (DPPH). GC-MS analysis identified glucose as the predominant sugar (>80%), followed by galactose and mannose. Additionally, HPLC detected a photoprotective compound, potentially a mycosporin-like amino acid. Cytotoxicity assays demonstrated PsBu’s selective activity against colon, lung, and melanoma cancer cell lines (IC₅₀: 100–500 µg·mL⁻¹), while effects on normal cell lines were lower (IC₅₀ > 1300 µg·mL⁻¹ for HaCaT, >2500 µg·mL⁻¹ for HGF-1), with SI values approaching 27, supporting PsBu’s potential as a targeted anticancer agent. Zebrafish embryo assays yielded LC₅₀ values ranging from 1.4 to 1.8 mg·mL⁻¹. In vivo, PsBu reduced fasting blood glucose levels in hyperglycemic rats (approximately 210 mg·dL⁻¹ vs. 230 mg·dL⁻¹ in controls) and preserved pancreatic β-cell integrity (around 80% vs. 65% in controls). Conclusions: These findings suggest that B. utriformis biomass and PsBu exhibit strong antioxidant activity, selective cytotoxicity against cancer cells, and antihyperglycemic potential, making them promising candidates for further biomedical applications. Full article

Neurocytotoxicity elicited by N-methyl-D-aspartate receptors (NMDAR) is a substantial contributor to neurodegenerative diseases. Our current study expands on the previous findings in which Periplaneta americana (L.) extract (PAS840) was shown to protect PC12 cells from hydrogen peroxide-induced injury. In this investigation, we performed LC-MS/MS and peptidomics analyses on the constituents of PAS840. Considering Alzheimer’s disease (AD) as the primary focus, we utilized network pharmacology and molecular-docking techniques to predict PAS840’s influence on AD targets. We established a glutamate (Glu)-induced PC12 cell injury model to conduct a comprehensive examination of PAS840’s effects on pivotal cellular parameters, including intracellular Ca²⁺ levels, superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, reactive oxygen species (ROS) levels, cell apoptosis rate, mitochondrial membrane potential (MMP) levels, and the expression of key proteins such as NMDAR1, cytochrome c (Cytc), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-3, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). The results suggest that PAS840 manifests multi-target actions, robustly attenuating NMDAR activity. It efficaciously suppresses excessive NMDAR1 activation, restricts Ca²⁺ influx, alleviates oxidative stress, and mitigates inflammation, thereby ameliorating neuronal cell damage. Consequently, it establishes a solid scientific foundation for further exploration of PAS840’s potential in addressing neurological diseases. Full article

Nakaseomyces glabrata (Candida glabrata), the second most prevalent Candida pathogen globally, has emerged as a major clinical threat due to its ability to develop high-level azole resistance. In this study, two new 5,6-dihydrotetrazolo[1,5-c]quinazoline derivatives (c11 and c12) were synthesized and characterized using IR, LC-MS, ¹H, and ¹³C NMR spectra. Along with 13 previously reported analogues, these compounds underwent in vitro antifungal testing against clinical N. glabrata isolates using a serial dilution method (0.125–64 mg/L). Remarkably, compounds c5 and c1 exhibited potent antifungal activity, with minimum inhibitory concentrations of 0.37 μM and 0.47 μM, respectively—about a 20-fold improvement in μM concentration over standard drugs like amphotericin B, caspofungin, and micafungin. A detailed structure–activity relationship analysis revealed crucial molecular features enhancing antifungal potency. Extensive molecular docking studies across 18 protein targets explored potential binding pockets and affinities of the lead compounds. A robust 3D-QSAR model, incorporating molecular descriptors Mor26m and Mor29e, displayed good predictive ability for antifungal activity. In silico predictions indicated an absence of herbicidal effect, negligible environmental toxicity (to honeybees, avian species, and aquatic organisms), and mild human toxicity concerns for these compounds. This comprehensive approach aims to develop novel and effective antifungal compounds against the clinically relevant pathogen N. glabrata. Full article

In the field of industrial lubrication, solid–liquid composite lubrication (SLCL) techniques based on diamond-like carbon (DLC) coatings and lubricating oils are emerging recently, which may be applied in many fields in the near future, especially automotive industries. The tribological behaviors of SLCL systems depend strongly on the compatibility between DLC coatings and oils. This review describes the advantages of SLCL techniques by pointing out the synergistic effects between DLC coatings and lubricating oils. Then the main factors determining the tribological performance of SLCL systems are discussed in detail. Finally, a conclusion about the characteristics of reported SLCL systems is made, and a prospect about the potential development of SLCL technology is proposed. On the basis of the relevant literature, it could be found that the tribological properties of SLCL systems were influenced by many more factors compared with individual DLC lubrication or individual oil lubrication due to the complicated tribo-chemical reactions involving DLC and oil during friction. And under some optimized working conditions, the tribological performances of SLCL systems (friction and wear reduction) are superior to individual DLC lubrication and individual oil lubrication. However, the tribological performance of SLCL systems needs to be further improved (for example, to achieve superlubricity and ultra-low wear simultaneously) by adjusting the structures of DLC coatings, regulating the compositions of oils, and most importantly, enhancing the physicochemical and tribological synergies between DLC coatings and oils. This review provides a comprehensive understanding of the SLCL technology, which may be very helpful for the researchers and engineers in the field of industrial lubrication and tribology. Full article

This paper presents a comprehensive study on the design and performance of a high-power amplifier (PA) covering a broad frequency band from 0.1 to 4.8 GHz. Leveraging a 10 W GaN device, the amplifier achieves output power levels surpassing 10 W across the entire frequency band. Furthermore, the power-added efficiency (PAE) of the amplifier ranges from 47% to 59%, indicating its energy-efficient operation. With consistent gain characteristics varying between 7 and 15 dB, the design ensures reliable signal amplification for diverse applications. Notably, the approach introduces a simplified output matching network based on an LC network, prioritizing practicality without sacrificing performance. Additionally, comprehensive guidance is provided on utilizing the Smith chart for streamlined amplifier design, enabling engineers with an accessible methodology. Through a meticulous analysis, this work contributes to advancing the field of high-power amplification, offering enhanced performance and usability for next-generation wireless communication systems. Full article