Search Results (1,078)

Evidence regarding tantalum nitride (TaN)-coated gold abutment screws is lacking, and studies on diamond-like carbon (DLC)-coated and anaerobic adhesive-coated abutment screws remain limited. This study evaluated the reverse torque values (RTVs) of abutment screws with different surface modifications. Sixty abutment screws from the same implant system were divided into five groups (n = 12): gold, TaN-coated gold, titanium, DLC-coated titanium, and anaerobic adhesive-coated titanium. Abutments were tightened according to the manufacturer’s recommended torque. Specimens were then subjected to cyclic loading (50 N, 1 Hz, 480,000 cycles) in a dual-axis chewing simulator, after which RTVs were evaluated. ANOVA showed a significant difference only for the uncoated gold screw group (p < 0.05). The lowest RTVs were observed in the gold screws. Although the differences among the modified screw groups were not statistically significant, surface-treated screws demonstrated higher and more stable RTVs than their uncoated counterparts. TaN-, DLC-, and anaerobic adhesive-treated screws exhibited higher RTVs following cyclic loading, suggesting that these surface modifications may enhance screw stability and reduce the risk of abutment screw loosening. Full article

Background: Rabies is a nearly 100% fatal zoonosis, and a rabies virus-neutralizing antibody (RVNA) titre of ≥0.5 IU/mL is the recognized correlate of protection, making post-vaccination serological monitoring essential. However, the gold-standard methods (RFFIT and FAVN) are time-consuming, require live virus, and are unsuitable for large-scale surveillance, while current ELISA kits often show poor concordance with neutralization tests. Methods: In this study, we established a chemiluminescence immunoassay (CLIA) employing magnetic beads coated with recombinant RABV glycoprotein (short-chain) and an acridinium ester-labeled rabbit anti-dog IgG. Results: The assay exhibited a detection limit of 0.24 IU/mL. Its performance was validated with 250 canine anti-RABV serum samples against the FAVN. The CLIA and FAVN results were strongly correlated (r = 0.9636, p < 0.0001), with a Deming slope of 0.96 (95% confidence interval: 0.92–1.00). The assay achieved a diagnostic sensitivity of 94.4% and a specificity of 97.1%. It demonstrated high accuracy (relative bias within ±10%), good repeatability (intra- and inter-assay coefficients of variation < 8%), and acceptable specificity, showing no cross-reactivity with canine parvovirus, canine distemper virus, or canine parainfluenza virus antibodies. Conclusions: This CLIA kit eliminates the need for live virus, yields quantitative results within 30 min, and offers simple operation and high-throughput capacity, making it a reliable and practical tool for rabies immune monitoring and scientific prevention and control. Full article

The Hyperspectral Infrared Atmospheric Sounder II (HIRAS-II) onboard the Fengyun-3 satellites is a Fourier-transform infrared spectrometer that requires high radiometric calibration accuracy, making the characterization and correction of polarization effects essential. Although the gold-coated scan mirror introduces only weak polarization, its rotation changes the polarization orientation relative to the fixed polarization-sensitive axis of the downstream optics, producing scan-angle-dependent radiometric errors. To characterize and correct this effect, we designed and constructed a dedicated polarization test apparatus and used it to conduct a prelaunch thermal-vacuum (TVAC) polarization test. During the test, HIRAS-II observed the same stable 290 K area-source blackbody over a densely sampled scan-angle range, with the internal calibration target and cold shield serving as the warm and cold references, respectively. Guided by a polarization-induced radiometric error model formulated within the two-point calibration framework, we developed a decoupled two-step least-squares method to retrieve the polarization parameters from the resulting measurements. The method first estimates the equivalent polarization-axis angle of the downstream optical system from the phase of the band-averaged angular modulation and then retrieves the effective combined polarization parameter separately for each field of view (FOV) and spectral channel. The retrieved parameters were subsequently used to calculate the scan-angle-dependent polarization correction term and correct the calibrated spectra. After correction, the FOV-averaged standard deviation over the scan angle decreased from 0.023 to 0.007 K, from 0.024 to 0.007 K, and from 0.045 to 0.014 K in the long-wave (LW), mid-wave 1 (MW1), and mid-wave 2 (MW2) bands, respectively. The corresponding maximum reductions in brightness temperature deviation were 0.093, 0.064, and 0.174 K. The model, experimental approach, and retrieved prelaunch parameters establish a basis for the on-orbit evaluation and correction of scan-angle-dependent polarization-induced radiometric errors. Reducing these errors improves the radiometric calibration accuracy of HIRAS-II and helps provide more reliable Level-1 radiance data for atmospheric profile retrievals and data assimilation in global numerical weather prediction (NWP) systems. Full article

Gold-sputtered tapered optical fiber (Au-TOF) sensors were developed for high-sensitivity refractive-index (RI) detection using aqueous glucose standards spanning 1.33–1.41 RIU (0–50% w/v). The sensors were fabricated using a reproducible workflow combining flame-brushing tapering, plasma surface preparation, and rotational magnetron sputtering, enabling azimuthally uniform gold coatings without the use of thiol or sulfur linker chemistries. Two sputtering durations (24 s and 30 s) were investigated to examine thickness-dependent plasmonic coupling and sensing performance. Optical measurements were conducted using a broadband supercontinuum source and compact spectrometer within a 20 µL microfluidic sensing chamber. Increasing glucose concentration produced a monotonic decrease in transmission intensity and a systematic red shift of the resonance minimum, consistent with enhanced evanescent-field interaction at the gold–dielectric interface. Across four independent trials, the 24 s Au-TOF sensor exhibited sensitivities up to 985 nm/RIU, while the 30 s device achieved sensitivities up to 1590 nm/RIU with strong linearity (R² = 0.99). The enhanced sensitivity observed for the longer sputtering duration is attributed to improved gold film continuity and stronger plasmonic coupling. These results demonstrate a scalable, linker-free fabrication strategy for plasmonically enhanced tapered fiber sensors and establish the Au-TOF platform as a promising approach for label-free optical biosensing in compact microfluidic environments. Full article

Metal-bearing tailings, slimes, metallurgical residues, spent catalysts, ashes, sludges, batteries, and electronic wastes are increasingly important secondary resources, but recovery is constrained by low and variable grades, fine particles, complex phase associations, passivation, and impurity-sensitive downstream processing. Hydrodynamic cavitation (HC) can modify selected flowsheet functions through interfacial renewal, localized mechanical action, gas–liquid transfer, fine-bubble generation, particle conditioning, and phase dispersion. The evidence was critically appraised across three independent dimensions: system relevance, causal attribution, and endpoint completeness. Application-level evidence is most developed for transport intensification in selected scheelite, uranium-bearing, and refractory-gold systems; particle conditioning and washing; spent-catalyst coating liberation; metal-bearing sludge treatment; copper cementation; and preparation of liquid emulsion membranes. Representative secondary-feed studies report conditioning, preconcentration, mobilization, and downstream separation responses, but complete feed-to-product recovery with controlled liquid and solid loops remains uncommon. Evidence is especially limited for battery black mass, electronic wastes, rare-earth-bearing residues, complex slags, metallurgical dusts, and multi-metal streams. HC is therefore most credible as a targeted module applied to a verified process limitation. A flowsheet advantage is established only when local gains persist through product recovery without offsetting increases in chemical use, water demand, energy consumption, equipment wear, or residual-stream burden. Full article

We present a dual-wavelength analysis of nitrogen-vacancy (NV) center quantum magnetometry enhanced by uniformly coated gold nanoparticles (AuNPs). An ensemble-averaged model is developed to analyze the AuNP-enhanced stimulated absorption at the 532 nm excitation wavelength and the spontaneous emission at 637 nm. The resulting detected optically magnetic resonance (ODMR) signal profiles are simulated for both enhancement mechanisms. We find that the enhanced stimulated absorption at 532 nm significantly amplifies the ODMR signal intensity without broadening the linewidth, thereby improving the signal-to-noise ratio (SNR) without sacrificing the magnetic field sensing resolution. Conversely, enhancing the 637 nm spontaneous emission increases the total photo emission rate but simultaneously broadens the ODMR detection linewidth due to the direct reduction in the effective spin coherence time of excited states by the enhanced spontaneous rate. The dual-wavelength analysis provides valuable design guidance for the development of low-cost spin-coated AuNP-enhanced NV-center quantum magnetometry technologies. Full article

In the present work, we investigated the role of polydopamine coatings in anchoring TiO₂ P25 nanoparticles on gold and ITO surfaces. For this purpose, we studied the adhesion of polydopamine-coated aggregates of TiO₂ nanoparticles on bare substrates and of aggregates of bare TiO₂ nanoparticles on polydopamine-coated substrates. Coating with polydopamine was accomplished by oxidation in air of alkaline aqueous dopamine solutions in which the nanoparticles or the substrates were immersed. Dynamic light scattering, Fourier transform infrared spectroscopy, and transmission electron microscopy were used for the chemical and morphological characterization of aggregates of the nanoparticles. The adhesion of aggregates of the nanoparticles on the substrates was evaluated by means of AFM and XPS. The results of this study suggest that the adhesion of TiO₂ P25 nanoparticles on polydopamine films, as well as of polydopamine-coated TiO₂ P25 nanoparticles, is a balance of several contributions: chemical interactions, electrostatic interactions, and coating roughness. Electrostatic attraction and repulsion between nanoparticles and the substrate appear to play an important role, as indicated by the ζ-potential values of nanoparticles and substrates. Full article

Wearable sweat biosensors require electrode materials with high surface area, conductivity and mechanical compliance, yet chemically polymerized polyaniline forms dense, low-surface-area films with limited flexibility. In this work, flexible free-standing nanofiber mats were fabricated by coaxial electrospinning, using a sulfuric-acid-doped polyacrylonitrile/polyaniline (PAN/PANI) core and a shell containing graphene oxide nanoscrolls (GONS) at 1 and 3 wt%, followed by gold nanoparticle and ferrocene incorporation, glucose oxidase (GOx) immobilization and a Nafion coating. Scanning electron microscopy showed uniform bead-free fibers with an interconnected pore network and an apparent image-derived porosity of approximately 40%. Energy-dispersive X-ray spectroscopy confirmed the uniform distribution of carbon, oxygen, nitrogen and sulfur across the matrix. Fourier-transform infrared spectroscopy retained the nitrile band at 2243 cm⁻¹ and the quinoid and benzenoid bands at 1547 and 1476 cm⁻¹, while amide bands at 1730 and 1641 cm⁻¹ confirmed retention of protein from enzymes. X-ray diffraction gave crystallinities of 76.6% for GONS and 60% for the pure PANI. Four-point probe measurements showed conductivity increasing from 0.0481 S/cm to 1 wt% GONS to 0.0595 S/cm for the 3 wt% mat with additives. These material and structural characterizations establish a promising foundation for future electrochemical validation and sensor development. Full article

This study presents an electrothermal coating approach for synthesizing cell-imprinted polymers (CIPs) on metallic microwires through localized resistive heating-induced polymerization. Imprinted polymers (IPs) are robust, cost-effective synthetic affinity materials widely used in sensing applications. However, conventional fabrication methods, including bulk and suspension polymerization, often lack spatial control, producing non-specific polymerization, heterogeneous coatings, and reduced sensor reproducibility. Electrochemical polymerization provides improved spatial control but requires specialized instrumentation and restricts monomer selection. Here, applying direct current (DC) to metallic microwires immersed in a prepolymer solution generated localized Joule heating, enabling controlled in situ polymerization and uniform coatings while minimizing undesired bulk polymerization. By optimizing the applied current and polymerization time, CIP coatings with tunable thicknesses were fabricated on gold-coated microwires. Under optimized conditions, ~6 µm thick coatings were imprinted using Salmonella templates. Scanning electron microscopy revealed bacteria-shaped cavities consistent with template removal and the formation of imprinted cavities. Rebinding experiments demonstrated enhanced bacterial capture, with CIP-coated microwires achieving ~70% capture efficiency, compared to 22% for bare microwires and 33% for non-imprinted polymer (NIP) controls. These results support the effectiveness of the proposed method for localized polymerization and demonstrate the enhanced capture of the template species by CIP-coated microwires relative to bare microwires and NIP-coated controls. Full article

Conventional oral and injectable drug administration still struggles with unstable plasma levels, weak targeting, and considerable systemic toxicity, problems that become especially acute in chronic disease management. Implantable and wearable biomedical devices offer one path around these limits, yet device-only platforms continue to fall short on drug loading, release control, and protection of fragile therapeutics. Integrating nanoparticle-based biomaterials into such devices has therefore moved from a research curiosity to a serious clinical strategy. As a result, understanding the design principles, translational challenges, and clinical potential of these hybrid platforms has become increasingly important. This review provides a comprehensive assessment of four major nanoparticle families—polymeric carriers (PLGA, chitosan, and micelles), lipid-based vehicles (liposomes, SLNs, and NLCs), inorganic systems (gold, mesoporous silica, iron oxide, and calcium phosphate), and hybrid composites—focusing on how their physicochemical properties govern drug encapsulation, release behavior, and tissue compatibility. These classes are then linked to specific implantable formats such as drug-eluting stents, nano-enabled scaffolds, and reservoir depots, and to wearable formats including transdermal patches, microneedle arrays, biosensor-coupled patches, and patient-actuated devices. A dedicated section addresses stimuli-responsive release driven by pH, enzymes, temperature, and electrical or magnetic fields, alongside closed-loop platforms that pair real-time biosensing with on-demand dosing. Surface engineering strategies, ligand targeting, antifouling coatings, antimicrobial layers, and immune-modulating chemistries are also discussed, together with the central translational hurdles: long-term stability, foreign body response, scale-up, sterilization, and regulatory classification of combination products. Finally, the review outlines near-term directions, including AI-driven dosing, 4D bioprinting, biomimetic nanocarriers, gene therapy delivery, and bioresorbable electronics, that together suggest where these hybrid platforms are likely to mature next. Full article

Peste des petits ruminants virus (PPRV) causes a highly fatal disease that severely impacts small ruminant production and global food security. This study aimed to develop a rapid, user-friendly colloidal gold immunochromatographic test strip for detecting PPRV-specific antibodies using a double-antigen sandwich format. Bioinformatic analysis using DNASTAR Protean was performed to predict candidate antigenic regions in the PPRV H and N proteins. Three predicted candidate regions from each protein were selected and incorporated into the design of the recombinant fusion antigen PPRV-H₃N₃EP. The recombinant antigen was expressed in E. coli, purified, and refolded to obtain a final concentration of 8.52 mg/mL. The strip was assembled with colloidal gold-labeled fusion protein as the detection probe and unlabeled protein coated on the test line, plus an independent mouse IgG/goat anti-mouse IgG control system. Performance evaluation showed that the results were readable within 10–15 min. The strip showed satisfactory analytical sensitivity and cross-reactivity performance, consistent qualitative results in within-batch repeatability testing, and preliminary short-term storage stability. In a comparative evaluation using sheep serum samples and a commercial competitive enzyme-linked immunosorbent assay (ELISA) kit, the overall agreement reached 97.9%. Collectively, the constructed PPRV-H₃N₃EP antigen enabled a simple, rapid, and reliable strip assay suitable for field detection of PPRV antibodies and post-vaccination monitoring, while also providing a methodological reference for developing antibody tests for other pathogens. Full article

In scientific literature, the biosynthesis of gold and silver nanoparticles and synthesis of these nanoparticles using small organic molecules such as citrate have been called ‘green’ processes. In abstracts of scientific publications, gold or silver nanoparticles obtained by ‘green’ synthesis have rather frequently been characterized as biocompatible. Biocompatible means having no negative impact on exposed organisms. Two reasons have been used to underpin this characterization. The first is the biocompatibility of the substances used in ‘green’ synthesis and coating nanoparticles. This reason lacks a solid empirical basis. The second reason given for biocompatibility is limited testing of the nanoparticles obtained by ‘green’ synthesis (mainly in vitro testing). Such limited testing is inconclusive. Use-specific comprehensive in vitro and in vivo testing, including clinical studies, and control of hazardous substances such as lipopolysaccharide and flagellins are needed to provide a solid basis for their characterization as biocompatible for humans. Full article

Background/Objectives: Glass-hybrid and high-viscosity glass ionomer systems were developed to address limitations of conventional glass ionomer cements. This in vitro study compared post-thermocycling Vickers hardness and microleakage of a coated glass-hybrid system and a coated high-viscosity glass ionomer system in conservative Class II cavities. Methods: Thirty extracted human maxillary first premolars each received both systems in standardized mesio-occlusal and disto-occlusal cavities, enabling paired within-tooth comparisons. Following thermocycling and methylene blue immersion, Vickers hardness was measured on polished restoration cross-sections at occlusal and gingival locations. Microleakage was quantified using a continuous microleakage index and ordinal dye penetration scores. Results: The EQUIA Forte HT system had a higher tooth-level mean Vickers hardness than the Gold Label IX Extra system (95.05 ± 6.58 HV vs. 91.33 ± 7.50 HV), with a mean paired difference of 3.72 HV (95% CI, 0.32 to 7.11; p = 0.033; Cohen’s d_z = 0.41, 95% CI, 0.03 to 0.78). The location-specific mixed model also showed an effect of restorative system (p = 0.025), whereas neither testing location nor the system × location interaction was significant. No significant between-system difference was detected for the microleakage index or for either ordinal dye penetration score. Conclusions: Within the limitations of this in vitro study, the EQUIA Forte HT system had a modestly higher post-thermocycling tooth-level mean Vickers hardness than the Gold Label IX Extra system, although the clinical relevance of the difference remains uncertain. No between-system differences were detected in dye penetration outcomes. Full article

Pulse-reverse electrodeposition was investigated as a route to reduce Au consumption while maintaining coating continuity and corrosion performance in thin Ni/Au finishes. A pulse-plated Ni barrier layer with an average thickness of approximately 4.45 μm was first prepared on brass, followed by Au deposition from a potassium dicyanoaurate-based electrolyte containing a cobalt additive. Pulse frequency, duty cycle, forward current density, and reverse current density were evaluated with respect to Au thickness, surface morphology, corrosion potential, roughness, and electrochemical impedance. The processing window was selected hierarchically by requiring an Au thickness of 0.3–0.6 μm, a relatively noble corrosion potential, a compact surface with few visible defects, low roughness, and a consistent impedance response; charge-transfer resistance was not treated as the sole criterion. Within the present bath, substrate, electrode geometry, and power-supply configuration, 800 Hz, 22% duty cycle, 0.11 A·dm⁻² forward current density, and −0.004 A·dm⁻² reverse current density provided the most balanced overall response. Full article

Titanium remains the gold standard in dental implantology; however, its clinical drawbacks, such as hypersensitivity reactions, metallic particle release, and aesthetically compromising discoloration, have driven interest in metal-free alternatives. Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) has emerged as a promising bioceramic candidate, offering favorable aesthetics, mechanical strength, and reduced bacterial plaque affinity. Its pristine surface is nonetheless bioinert, prompting extensive research into surface modification strategies, including sandblasting, acid-etching, femtosecond laser texturing, and bioactive coatings, to enhance osteoconductivity. This comprehensive narrative review synthesizes in vitro evidence on the behavior of key host cell populations—macrophages, mesenchymal stem cells, osteoblasts, fibroblasts, and epithelial cells in response to Y-TZP surface and its modifications, relevant to osseointegration and soft-tissue sealing. A literature search was conducted across PubMed, Scopus, Web of Science, and the Cochrane Library, supplemented by Google Scholar, concluding in March 2026. By integrating findings across multiple cell lineages, this review aims to clarify how engineered zirconia topographies modulate cell-specific pathways, thereby informing the development of next-generation implants optimized for biological integration. Full article