Search Results (460)

Precise control over defect structures is essential for tuning the functional properties of lithium niobate (LiNbO₃) crystals. Although the threshold effect of Hf⁴⁺ doping is well recognized, its underlying atomic-scale mechanism, especially in systems co-doped with luminescent rare earth ions, remains unclear. In this study, we combine experimental and theoretical approaches to elucidate the Hf⁴⁺ concentration-driven threshold behavior in Dy: LiNbO₃ crystals. A series of crystals with Hf⁴⁺ concentrations of 2, 4, 6, and 8 mol% were grown using the Czochralski method. Characterization through XRD and IR spectroscopy identified a threshold near 4 mol%, evidenced by an inflection in lattice constants and a pronounced blue shift of the OH⁻ absorption peak. UV–Vis–NIR absorption spectra revealed a systematic enhancement of Dy³⁺f–f transition intensities, linking the global defect structure to the local crystal field of the optical activator. First-principles calculations showed that Hf⁴⁺ ions preferentially occupy Li sites, repairing antisite Nb defects ($\mathrm{N}{\mathrm{b}}_{\mathrm{Li}}^{4+}$) below the threshold, and incorporate into Nb sites beyond it, inducing structural reorganization. Electron Localization Function analysis visualized strengthened Hf-O covalent bonding in the post-threshold regime. This work establishes a complete atomic-scale picture connecting dopant site preference, chemical bonding, and macroscopic properties, providing a foundational framework for the rational design of advanced LiNbO₃-based materials. Full article

This paper presents a high-efficiency wireless power transfer (WPT) architecture employing a resonant inductive coupling to power smart sensor nodes in remote or sealed environments, where conventional power delivery is unfeasible. The system integrates a photovoltaic (PV) energy source with a step-down DC-DC converter based on the LM2596 buck regulator to adjust the voltage from the PV. The proposed conditioned power system supplies the entire electronic circuit consisting of a PWM modulator based on an NE555, which drives an IR2110 gate driver connected to a Class D power amplifier. The amplifier excites a pair of high-Q resonant coils designed for mid-range inductive coupling. On the receiver side, the inductively coupled AC signal is rectified and regulated through an AC-DC conversion stage to charge a secondary energy storage unit. The design eliminates the need for physical electrical connections, ensuring efficient, contactless energy transfer. The proposed system operates at a resonant frequency of 24.46 kHz and achieves up to 80% transmission efficiency at a distance of 113 mm. The receiver provides a regulated DC output between 4.80 V and 4.97 V, sufficient to power low-consumption smart sensors. Full article

Lycopene is a potent antioxidant carotenoid with significant health-promoting properties. However, its practical application is limited by poor water solubility. This study aimed to enhance lycopene dispersibility through the development of solid dispersions obtained by hot-melt extrusion (HME). Polymeric carriers composed of polyvinylpyrrolidone K30 (PVP K30), phosphatidylcholine, and xylitol were designed to achieve optimal processing conditions and thermal stability. Nine formulations containing 10–30% lycopene were prepared and characterized using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FT-IR), and dispersibility testing. TGA confirmed the thermal stability of lycopene at the extrusion temperature (150 °C). DSC and XRPD analyses indicated partial amorphization of lycopene in the extrudates, while FT-IR spectra revealed molecular interactions between lycopene and carrier components, particularly hydroxyl and carbonyl groups. Among the tested systems, the formulation containing PVP K30 and xylitol without phosphatidylcholine exhibited the highest dispersibility (1.0484 mg/mL after 3 h). Dispersibility decreased with increasing lycopene content. These findings demonstrate that HME is an effective technique for producing partially amorphous lycopene dispersions with improved dispersibility, and that polymer–polyol systems are particularly promising carriers for enhancing lycopene bioavailability. Full article

This paper presents an intelligent robotic system for in-pipe inspection that integrates a novel mechanical design, deep learning-based defect detection, and high-fidelity simulation for real-time validation. Unlike existing solutions, the proposed system combines a Mecanum wheel-based mobile platform with a modular arm and advanced pan-tilt camera, enabling navigation and inspection of pipes ranging from 100 mm to 500 mm in diameter. A comprehensive dataset of 53,486 images, including 27,000 annotated defect instances across six critical classes, was used to train a YOLOv11-based detection framework. The model achieved high accuracy with a precision of 0.9, recall of 0.8, mAP@0.5 of 0.9, and mAP@0.5:0.95 of 0.6, outperforming previous YOLO versions, SSD, RCNN, and DinoV2 by 26% in mAP. Real-time testing on a Raspberry Pi Camera 3 Wide IR module validated the robust detection under realistic conditions. This work contributes a mechanically adaptable robot, an optimized deep learning inspection framework, and an integrated simulation-to-deployment workflow, providing a scalable and autonomous solution for industrial pipeline inspection. Full article

Assumptions about environmental and operational conditions play a key role in the design of sensor-driven and cyber–physical systems. When these assumptions later change or prove incorrect, they can cause rework, inconsistency, and other forms of requirements technical debt (RTD). Although prior studies have highlighted this problem conceptually, there has been limited quantitative evidence showing how assumptions volatility contributes to RTD during early system modeling. Objective: This work introduces the concept of assumptions volatility, the degree to which environmental assumptions evolve or become invalid, and provides the first empirical assessment of how these measures relate to RTD indicators in model-based development. Methods: We analyzed 89 environmental assumptions curated from a prior controlled modeling study. For assumptions volatility, we identified three metrics, i.e., assumption change (ACR), invalidation ratio (IR), and dependence density (DD). These measures were compared against three RTD indicators, i.e., rework ratio, inconsistency density, and correction count. Correlation and regression analyses with robustness checks were used to evaluate the strength and consistency of the observed relationships. Results: Our results showed that assumptions with higher volatility were consistently linked to a greater level of RTD, with dependency density showing the most stable associations among the three volatility measures. Conclusions: The findings provide initial quantitative evidence that environmental assumption volatility is associated with RTD during conceptual design and motivate future multi-domain validation in broader Model-based Systems Engineering settings. Full article

The design of sustainable hydrogel materials with tunable mechanical and thermal properties is essential for emerging applications in flexible and wearable electronics. In this study, hydrogels based on natural gums such as Guar, Tara, and Xanthan and their composites with Cellulose Citrate were developed through a mild physical crosslinking process, ensuring environmental compatibility and structural integrity. The effect of cellulose citrate pretreatment under different alkaline conditions (0.04%, 5%, and 10% NaOH) was systematically investigated using Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), and dynamic rheology. Overall, the results show that the composites exhibit different properties of the hydrogel networks compared to the pure hydrogel gums, strongly depending on the alkaline treatment. In all composite hydrogels, a significant increase in the number of interacting rheological units occurs, though the strength of the interactions decreases in Guar and Tara composites, which exhibit partial structural destabilization. In contrast, Xanthan–Cellulose Citrate hydrogels display enhanced strong gel character, and crosslinking density. These improvements reflect stronger intermolecular associations and a more compact polymer network, due to the favorable H-bonding and ionic interactions among Xanthan, Cellulose and Citrate mediated by water and sodium ions. Overall, the results demonstrate that Xanthan–Cellulose Citrate systems represent a new class of eco-friendly, mechanically robust hydrogels with controllable viscoelastic and thermal responses, features highly relevant for the next generation of flexible, self-supporting, and responsive soft materials suitable for wearable and stretchable electronic devices. Full article

Diabetes mellitus (DM) is a chronic non-communicable disease associated with macroangiopathy and microangiopathy, with disabling or even life-threatening complications. In the present study, we aimed to analyze the association between insulin resistance (IR) and inflammation biomarkers and peripheral arterial disease (PAD) and diabetic peripheral neuropathy (DPN), respectively. The study had a cross-sectional design and evaluated a panel of IR related indices and inflammatory biomarkers commonly used in clinical and epidemiological research, including the triglyceride-glucose (TyG) index and its obesity related derivates, cholesterol, HDL, glucose (CHG) index, lipid-derived ratios, and composite inflammatory indices, together with interleukin-6 (IL-6), tumor necrosis factor alpha (TNFα) and C-reactive protein (CRP) in 110 subjects, according to the presence or absence of PAD and DPN, respectively. In the PAD (+) group, TyG-waist-to-height-ratio (TyG−WHtR) and CHG recorded significantly increased values (p = 0.042, respectively p < 0.001), compared to PAD (−). CHG recorded significantly increased values in DPN (+) subjects (p = 0.007). In addition, in the PAD (+) subjects, IL-6 and systemic immune inflammation index (SII) recorded significantly increased values (p = 0.026, respectively, p = 0.015) and TNFα, monocyte to lymphocyte ratio (MLR) and C-reactive protein to albumin ratio (CAR) recorded significantly increased values in DPN (+) subjects (p = 0.028, respectively, p = 0.008, and p = 0.038). We developed a score with a good discriminatory performance for PAD and DPN, including DM duration, TyG−WHtR, SII, MLR and CAR (AUROC 0.822 in PAD, respectively 0.848 in DPN, p < 0.001). A composite score combining IR and inflammatory biomarkers showed strong discriminatory performance for lower limb complications in type 2 diabetes, suggesting a valuable tool for early detection and prevention. Full article

To develop a novel pH-responsive multifunctional wound dressing, this study designed a ferulic acid (FA)–cellulose-grafted polymer that leverages the pH-responsive properties of FA. This polymer enables the rapid detection of pH fluctuations in wound environments and effectively monitors acute inflammatory changes. This study innovatively employed FA as the functional compound, horseradish peroxidase (HRP)/ascorbic acid (AA) as the catalytic system, and hydrogen peroxide as the initiator, successfully achieving a grafting reaction between cellulose and FA. Through optimized experiments, the optimal amounts of the FA, AA, HRP enzyme, and hydrogen peroxide were determined. Under these optimal conditions, the K/S value of the FA-grafted fabrics exceeded one, with a grafting rate surpassing 1%. The structure of the cellulose–FA was characterized by FT-IR, HPLC, and ¹H NMR, and the possible grafting mechanisms were analyzed. Subsequently, FA-grafted fabric samples were immersed in solutions with varying pH levels, and the material’s pH responsiveness was analyzed through color changes. When the solution’s pH shifted from 3 to 12, the grafted fabric exhibited significant color variations. Consequently, FA-grafted cellulose shows great potential for monitoring skin wound acidity/alkalinity changes and detecting inflammatory responses. Full article

Heterocyclic systems such as 1,2,4-triazoles and piperazines play an important role in modern medicinal chemistry due to their structural diversity and broad spectrum of biological activities. In this Short Note, we report the synthesis and spectroscopic characterization of a new hybrid molecule combining both pharmacophoric fragments: 1-[4-(4-chlorophenyl)piperazin-1-yl]-2-[(4-phenyl-4H-1,2,4-triazol-3-yl)sulfanyl]ethan-1-one (compound 3). The compound was obtained in 70% yield via S-alkylation of 4-phenyl-1,2,4-triazole-3-thione with a chloroacetyl derivative of 4-chlorophenylpiperazine under alkaline conditions. The structure of 3 was confirmed by ¹H and ¹³C NMR spectroscopy, DEPT-135, 2D NMR (COSY, NOESY, HSQC, HMBC), FT-IR, and elemental analysis. These results support the utility of combining triazole and piperazine fragments in the design of new heterocyclic frameworks with potential biological relevance. Full article

Understanding how the surface charge environment governs pollutant–catalyst interactions is essential for designing efficient photocatalysts. In this study, ZnO–CeO₂–WO₃ composite materials were synthesized through a simplex-centroid mixture design to evaluate their photocatalytic activity toward the degradation of 4-nitrophenol (4-NPOH) under UV irradiation. The materials were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), UV–Vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL), nitrogen adsorption–desorption (BET/DFT) and scanning electron microscopy (SEM). Photocatalytic experiments were conducted without pH adjustment to analyze the intrinsic behavior of each oxide and their mixtures. The acid–base equilibrium of 4-NPOH (pK_a = 7.2) allowed evaluating its deprotonation to 4-nitrophenolate (4-NP⁻) and its interaction with the catalyst surface, which depends on the point of zero charge (pH_Pzc) of ZnO, CeO₂, and WO₃. The Zn–W binary system (ZnWO₄ phase) exhibited the highest activity, achieving 81% degradation efficiency and the largest apparent rate constant (k = 5.1 × 10⁻³ min⁻¹). However, a 51% decrease in activity was observed after three reuse cycles, attributed to WO₃ leaching induced by the interaction between 4-NPO⁻ and zinc tungstate hydroxide (Zn[W(OH)₈]). This work establishes a direct correlation between surface charge, pollutant speciation, and photocatalytic performance, providing a mechanistic framework for understanding pH-dependent degradation processes over multicomponent oxide composites. Full article

Sinomenine (SIN), as a potential therapeutic agent for rheumatoid arthritis (RA), exhibits advantages such as non-addictiveness. However, its low aqueous solubility and poor membrane permeability result in limited bioavailability, which compromises its therapeutic efficacy in conventional formulations. To address these limitations, this study developed nanostructured lipid carriers (NLCs) with optimized formulations and evaluated their pharmacodynamic performance. Molecular dynamics (MD) simulations were employed to screen excipients and analyze the blending system. SIN-loaded NLCs (SIN-NLCs) were prepared using high-pressure homogenization. Single-factor experiments were performed to optimize the processing conditions of SIN-NLCs. A three-factor, three-level experimental design was established using Design Expert 13 software and further refined through Box–Behnken design (BBD) response surface methodology. This approach enabled cross-validation between molecular dynamics simulations and conventional experiments. Additionally, transmission electron microscopy (TEM) was used to examine morphology, while X-ray diffraction analysis (XRD), differential scanning calorimetry (DSC), and Fourier-transform infrared spectroscopy (FT-IR) were employed to characterize the physicochemical state of SIN in NLCs. Pharmacodynamic evaluation was performed in a RA model, supplemented by single-pass intestinal perfusion study (SPIP). Initially, MD simulations were employed to evaluate drug–excipient compatibility, thereby identifying suitable formulation excipients: stearic acid and oleic acid as lipid components, and Poloxamer 188 as the surfactant. Subsequently, single-factor experiments combined with the BBD response surface methodology were employed to optimize preparation parameters, establishing the ideal process conditions: drug-to-lipid ratio of 1:42, solid-to-liquid lipid ratio of 5.58:4.42, and Poloxamer 188 concentration of 1.20%. The optimized SIN-NLCs exhibited spherical particles with uniform dispersion and no agglomeration. The average particle size was 173.90 ± 1.97 nm, with a polydispersity index (PDI) of 0.18 ± 0.01, a zeta potential of −22.65 ± 0.60 mV, and an encapsulation efficiency (EE%) of 91.27% ± 0.01. Spectroscopic analysis confirmed that SIN existed in an amorphous state and was successfully encapsulated within the lipid matrix. In vivo, SIN-NLCs significantly reduced paw swelling and arthritis scores in model rats, promoted synovial cell proliferation, and suppressed inflammatory cell infiltration. The intestinal perfusion study demonstrated that SIN-NLCs were primarily absorbed in the small intestine and markedly enhanced drug permeability. SIN-NLCs represent an effective delivery system to enhance the solubility and permeability of SIN. This study provides a novel strategy and methodology for the formulation of hydrophobic drugs, offering valuable insights for future pharmaceutical development. Full article

Pesticides play key roles in modern agricultural activities. Optimizing pesticide deposition is essential for maximizing utilization efficiency and minimizing unintended environmental impacts. While electrostatic, hydrogen, and covalent interactions have been extensively studied to modulate pesticide adhesion to leaf surfaces, the potential of metal coordination bonding to enhance foliar deposition remains largely unexplored. In our work, abamectin-loaded PLA nanospheres coated in tannic acid (TA) (Abam@PLA) via the metal chelating ability of polyphenols (Abam@PLA-TA) were developed to improve abamectin retention on the surfaces of leaves. The chemical properties and morphological features of Abam@PLA-TA were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and fluorescent imaging. The foliar retention of Abam@PLA-TA demonstrated that the tannic acid coating could significantly improve the adhesion ability and deposition efficiency of pesticides for crop leaves, which was mainly attributed to the hydrogen bonds between the polyphenols of TA and the polar groups of the wax layer. Moreover, Abam@PLA-TA exhibited better photostability capacity compared to the abamectin technical concentrate, which helps to protect light-sensitive pesticides from ultraviolet (UV) decomposition. This strategy opens up a simple but powerful avenue for the design of foliage adhesive systems and a new opportunity for the efficient utilization of pesticides. Full article

Background: The intersection between oncology and intensive care has shifted from predominantly end-of-life care to a therapeutic bridge that can preserve anticancer trajectories in carefully selected patients. Yet, criteria separating benefit from futility remain fragmented. Objective: This paper seeks to map contemporary evidence (2015–2025) on outcomes after Intensive Care Unit (ICU) admission in adults with cancer and to identify clinical constellations in which ICU-level care still changes prognosis. Methods: PRISMA-ScR scoping review (PCC framework). PubMed search (2015–2025), dual screening, standardized extraction; narrative/thematic synthesis across six clusters (hematologic, solid tumors, sepsis/non-COVID-19 infection, COVID-19/viral pneumonia, novel/targeted-therapy toxicities, end-of-life/aggressive ICU) were used. No meta-analysis given heterogeneity. Results: Seventy-three studies (>170,000 ICU admissions) were included, mostly cohort designs across 27 countries. ICU mortality ranged 8–72% (weighted mean ≈ 41%); hospital ≈ 38%; 90-day ≈ 46%; 1-year ≈ 62%. About one third of ICU survivors resumed systemic therapy. Benefit concentrated in early admissions, single-organ failure, controlled/remission disease, postoperative/elective monitoring, and reversible treatment-related toxicities (e.g., ICI pneumonitis, CAR-T CRS/ICANS). Futility clustered around ≥3 organ supports, RRT > 7 days, refractory/progressive disease, and ECOG ≥ 3. Sepsis outcomes averaged 45–55% ICU mortality but improved with rapid recognition and source control; COVID-19 mortality was particularly high in hematologic malignancies early in the pandemic, with subsequent declines post-vaccination. Conclusions: In modern oncologic practice, ICU care changes prognosis when the acute physiological insult is reversible and cancer control remains plausible; conversely, high organ-support burden and refractory disease define practical futility thresholds. These signals support time-limited ICU trials, earlier ICU involvement for sepsis/irAEs, and embedded palliative care to align intensity with goals. Full article

Electrocatalytic water splitting offers a promising route to sustainable H₂, but the oxygen evolution reaction (OER) in alkaline media remains the principal bottleneck for activity and durability. This review focuses on alkaline OER and integrates mechanism, kinetics, materials design, and cell-level considerations. Reaction mechanisms are outlined, including the adsorbate evolution mechanism (AEM) and the lattice oxygen mediated mechanism (LOM), together with universal scaling constraints and operando reconstruction of precatalysts into active oxyhydroxides. Strategies for electronic tuning, defect creation, and heterointerface design are linked to measurable kinetics, including iR-corrected overpotential, Tafel slope, charge transfer resistance, and electrochemically active surface area (ECSA). Representative catalyst families are critically evaluated, covering Ir and Ru oxides, Ni-, Fe-, and Co-based compounds, carbon-based materials, and heterostructure systems. Electrolyte engineering is discussed, including control of Fe impurities and cation and anion effects, and gas management at current densities of 100–500 mA·cm⁻² and higher. Finally, we outline challenges and directions that include operando discrimination between mechanisms and possible crossover between AEM and LOM, strategies to relax scaling relations using dual sites and interfacial water control, and constant potential modeling with explicit solvation and electric fields to enable efficient, scalable alkaline electrolyzers. Full article

The growing demand for compact, low-power infrared (IR) sensors necessitates advanced solutions for on-chip spectral selectivity, particularly for integration with Thermal Metal-Oxide-Semiconductor (TMOS) devices. This paper investigates the design and analysis of CMOS-compatible metal–insulator–metal (MIM) metamaterial absorbers tailored for selective absorption in the long-wave infrared (LWIR) region. We present a design methodology utilizing an equivalent-circuit model, which provides intuitive physical insight into the absorption mechanism and significantly reduces computational costs compared to full-wave electromagnetic simulations. An important rule in this design methodology is demonstrating how the resonance wavelength of these absorbers can be precisely tuned across the LWIR spectrum by engineering the geometric parameters of the top metallic patterns and, critically, by optimizing the dielectric substrate’s refractive index and thickness, which assist in designing small period MIM absorber units which are important in infrared thermal sensor pixels. Our results demonstrate that the resonance wavelength of these absorbers can be precisely tuned across the LWIR spectrum by engineering the geometric parameters of the top metallic patterns and by optimizing the dielectric substrate’s refractive index and thickness. Specifically, the selection of silicon as the dielectric material, owing to its high refractive index and low losses, facilitates compact designs with high-quality factors. The transmission line model provides intuitive insight into how near-perfect absorption is achieved when the absorber’s input impedance matches the free-space impedance. This work presents a new approach for the methodology of designing MIM absorbers in the mid-infrared and long-wave infrared (LWIR) regions, utilizing the intuitive insights provided by equivalent circuit modeling. This study validates a highly efficient design approach for high-performance, spectrally selective MIM absorbers for LWIR radiation, paving the way for their monolithic integration with TMOS sensors to enable miniaturized, cost-effective, and functionally enhanced IR sensing systems. Full article