Search Results (28,485)

The detection of chiral properties is crucial for pharmacology and biochemistry, yet standard circular dichroism spectroscopy suffers from low sensitivity when probing minute sample volumes. While complex asymmetric chiral nanostructures can enhance these Circular Dichroic (CD) signals, their fabrication is intricate and costly. In this work, we analyzed an alternative based on extrinsic chirality in achiral square arrays of plasmonic circular NHAs realized via Displacement Talbot Lithography (DTL), thus exploring the chiroptical response arising from symmetry breaking induced by oblique illumination. Unlike isolated nanoparticles, nanohole arrays (NHAs) support propagating Surface Plasmon Polaritons (SPPs), allowing for unique light confinement capabilities essential for high-throughput sensing. A careful characterization in terms of Stokes parameters has been performed over a selected range of different optical angles of incidence and sample orientation to disentangle extrinsic chiral contribution from spurious effects related to sample imperfections. By optimizing such extrinsic chiral contributions, enhanced chiroptical response could be engineered by significantly amplifying the interaction between light and chiral biomolecules trapped within the holes. This methodology establishes DTL-fabricated achiral NHAs as an ultrasensitive, cost-effective platform for the detection and discrimination of enantiomers in biosensing applications. Full article

Unstructured mesh deformation is an effective way to automatically generate mesh after geometric shape changes such as fluid–structure interaction simulation or aerodynamic shape optimization. The radial basis function method is one of the best mesh deformation methods, which takes into account both computational time and deformation ability. However, the current existing methods are confronted by the contradiction between computational efficiency and deformation accuracy. In this paper, a hybrid deformation method combining the radial basis function and distance-weighted function is proposed, which can effectively reduce computing cost and eliminate deformation error. Firstly, based on the radial basis function method with data reduction scheme, an efficient equidistant sampling method for points selection independent of the specific form of deformation is proposed, and a sampling algorithm based on bisection is devised to make the number of sample points quickly approach the expected value. Secondly, a compact distance-weighted function deformation method is developed, which is used to diffuse the deformation errors of boundary mesh points directly to interior mesh points in order to completely eliminate the deformation errors. Finally, two configurations, AGARD 445.6 wing and HIRENASD wing, are used to test the deformation capability of the hybrid method and the computing time of several key processes. The results show that the hybrid method can accurately realize large mesh deformation with a maximum displacement up to 50% span length, and at the same time, the mesh deformation can be completed with a single core in about 100 s for millions of mesh points, which indicates that the hybrid method in this paper has the ability to be applied to complicated configurations in real engineering. Full article

Laser powder bead fusion (LPBF) allows for the fabrication of highly accurate components from metal powders, which is difficult to achieve using traditional methods. LPBF-produced components can be characterized by their porosity and unfavorable microstructure, making further processing difficult. Therefore, appropriate post-printing methods are crucial, as they reduce porosity, reduce residual stresses, and stabilize the microstructure. The aim of this paper was to determine the effect of post-printing methods on the microhardness and microstructure of Ti6Al4V titanium alloy samples fabricated using the LPBF process in different orientations. Hot isostatic pressing (HIP) at various temperatures (910 °C, 1150 °C, 1250 °C), annealing at 1020 °C, and twist channel angular pressing using a 90° channel ending with a helical exit were considered postprocessing methods for LPBF-produced samples. Printing orientation significantly determined the effectiveness of HIP and the heat treatment processes. Higher microhardness was observed on the cross-section oriented perpendicular to the 3D printing direction. Annealing under appropriately selected conditions favors the precipitation of fine particles of the α phase in the β phase, leading to a strengthening effect by precipitation. Based on the microhardness measurements, clear differences were observed in the mean values, statistical ranges, and result distributions depending on the printing plane, HIP process parameters, and the use of an additional heat treatment. The HIP process leads to a more pronounced homogenization of microstructure and defect reduction, with the morphology of the microstructure and microhardness distribution dependent on the HIP process temperature. Full article

With the ongoing miniaturization of smart devices, fine-grained hand gesture recognition using millimeter-wave radar has attracted increasing attention, yet practical deployment remains challenging in continuous-gesture segmentation, robust feature extraction, and reliable classification. This paper presents an end-to-end fine-grained gesture recognition framework based on frequency modulated continuous wave(FMCW) millimeter-wave radar, including gesture design, data acquisition, feature construction, and neural network-based classification. Ten gesture types are recorded (eight valid gestures and two return-to-neutral gestures); for classification, the two return-to-neutral gesture types are merged into a single invalid class, yielding a nine-class task. A sliding-window segmentation method is developed using short-time Fourier transformation(STFT)-based Doppler-time representations, and a dataset of 4050 labeled samples is collected. Multiple signal classification(MUSIC)-based super-resolution estimation is adopted to construct range–time and angle–time representations, and instance-wise normalization is applied to Doppler and range features to mitigate inter-individual variability without test leakage. For recognition, a variable-channel deep residual shrinkage network (DRSN) is employed to improve robustness to noise, supporting single-, dual-, and triple-channel feature inputs. Results under both subject-dependent evaluation with repeated random splits and subject-independent leave one subject out(LOSO) cross-validation show that DRSN architecture consistently outperforms the RefineNet-based baseline, and the triple-channel configuration achieves the best performance (98.88% accuracy). Overall, the variable-channel design enables flexible feature selection to meet diverse application requirements. Full article

Groundwater microbial communities exhibit pronounced vertical and spatial structuring driven by physicochemical gradients. Here, we investigated microbial assemblages across surface and subsurface layers of three groundwater wells distributed along a 1.26 km transect in the Wadi Awja aquifer system (Jeddah, Saudi Arabia) using high-throughput 16S rRNA gene amplicon sequencing. Across all samples, Pseudomonadota (Proteobacteria) dominated community composition, accounting for ~50–65% of surface assemblages and increasing to ~90% in deeper strata, indicating strong vertical selection. This depth-associated enrichment coincided with reduced community evenness and the prevalence of metabolically versatile, facultatively anaerobic taxa. Although Actinomycetota, Bacteroidota, and Planctomycetota contributed substantially to overall diversity, their relative abundances declined with depth, reinforcing the dominance of Proteobacteria under suboxic conditions. Notably, members of Enterobacteriaceae, particularly Escherichia spp., were consistently enriched in deeper layers, coinciding with simplified community structures. Collectively, these results demonstrate that groundwater microbial communities undergo sharp redox-associated ecological transitions over short spatial scales, emphasizing the role of localized hydrogeochemical heterogeneity in shaping subsurface microbial assemblages. Full article

Water-lubricated bearings are critical components in marine propulsion systems, necessitating materials with exceptional tribological properties to ensure reliability. Filament-winding technology is an effective molding method for enhancing the comprehensive properties of polymers, and the selection of fiber materials has a significant impact on the performance of polymers. In this study, three types of polyurethane (PU) matrix filament-winding composites were fabricated via filament-winding technology. Under water-lubricated conditions, a friction test (disk-to-disk) with a duration of 2 h was performed, followed by systematic observations of the resultant wear behavior. The results indicate that aramid fibers exhibited the superior reinforcing effect on the PU matrix, effectively suppressing wear while enhancing mechanical properties. Specifically, under the conditions of 0.5 MPa-250 r/min (0.314 m/s), the minimum friction coefficient of the aramid fiber-wound composite material was 0.093, which was 57.73% lower than that of pure polyurethane. Under the conditions of 0.7 MPa-50 r/min (0.0628 m/s), the wear mass of the sample was limited to only 1.5 mg, which was 12% lower than that of polyurethane. This research can provide a practical reference for the application of filament-wound composite materials in water-lubricated bearings. Full article

Five Cornus mas L. genotypes were analysed based on their attractive colour and high productivity. The ‘Bordo’ cultivar stood out, demonstrating the highest berry weight (3.07 g) and yield per plant (8.24 kg). Close behind was the MH-7-17 selection, with an average yield of 7.37 kg per plant. Both the ‘Bordo’ cultivar and the MH-7-17 selection exhibited excellent agronomic potential, making them ideal candidates for large-scale cultivation. UV-Vis absorption spectroscopy was used to quantify the fruits’ levels of sugars, polyphenols, flavonoids, tannins, anthocyanins and carotenoids (lycopene and β-carotene) and to evaluate their antioxidant capacity. The ‘Bordo’ cultivar had the highest carotenoid content (0.88 mg lycopene and 2.47 mg β-carotene per 100 g), while the TG-J-9-17 and TG-J-20-17 selections had the highest total content of sugars, polyphenols, flavonoids, tannins and anthocyanins and the highest antioxidant capacity. According to the correlations analysis, bigger fruit (which correlated to higher yield) had higher carotenoid content, although lower-level tannin (TTC), flavonoid (TFC), anthocyanin (TAC), and sugar (TSC). Also, total phenolic content (TPC) was positively correlated to TTC, TFC, and radical scavenging activity (RSA), while TFC was positively correlated to TTC, TAC, RSA, but also to TSC. Other positive correlations were those found between TTC and RSA and between lycopene and β-carotene. FTIR spectroscopy was used to identify the characteristic vibrations of the biochemical constituents. Processing the FTIR data using chemometric techniques (principal component analysis and hierarchical clustering analysis) revealed consistent clustering patterns between samples with similar characteristics. Full article

This study investigates the influence of different sintering protocols and resin cement shades on the optical properties of monolithic zirconia restorations. Zirconia, widely used in dentistry for its superior mechanical strength and esthetic potential, demonstrates phase transformations influenced by stabilizing oxides and processing conditions. While increasing yttria content enhances translucency, it compromises mechanical durability. Factors such as sintering temperature, grain size, porosity, and cement selection further affect translucency parameter, contrast ratio, and opalescence. In this research, 36 zirconia samples were divided into three groups according to sintering procedure performed; conventional, fast, and super-fast sintering. Each was tested with two shades of dual-cure resin cement (yellow and transparent). Optical parameters including translucency parameter (TP), contrast ratio (CR), and opalescence parameter (OP) were measured using a spectrophotometer under controlled conditions. Statistically significant differences in OP values between the conventional sintering protocol and both the rapid and super-fast sintering protocols were found. A statistically significant difference was observed in OP values between the yellow and transparent cement groups. Neither the main effects of the sintering protocol nor the cement type were statistically significant on TP and CR values. However, a statistically significant interaction effect between the sintering protocol and cement type was observed for CR values. The findings highlight that both processing parameters and cement selection interaction play crucial roles in optimizing the TP and CR values of zirconia restorations, enabling improved esthetic outcomes in clinical practice. Full article

Delayed harvesting of grapes can alter fruit quality and plays an important role in alleviating the problem of market saturation during peak seasons, as well as in regulating the supply period of grapes. In this study, by conducting a comparative analysis of fruit quality, metabolomics (aroma compounds) and transcriptome sequencing of ‘Shine Muscat’ grapes harvested at six different on-tree ripening stages after maturity, we found that: (1) delayed harvesting led to dramatic variation in berry color change (light green to yellow) with a significant increase in soluble solids (19.5 to 20.89 Brix); (2) A total of 25 volatile aroma compounds was identified in collected berry samples, while trans-2-hexenal and hexanal exhibited the highest concentrations in all samples, marking them as key volatile compounds in ‘Shine Muscat’ grapes. Notable variation in the concentrations of linalool, n-butanol, benzyl alcohol, phenylethanol, β-citronellol, and propionic anhydride were recorded in selected harvest periods. OAV analysis results show that linalool has the largest OAV among the detected compounds, and its OAV proportion increased from 53% to 95% during the six sampling periods of ‘Shine Muscat’; (3) Transcriptome sequencing of selected samples demonstrated a positive correlation between eight terpene-synthesis-related genes and linalool accumulation. Furthermore, genes within the MEP pathway (specifically VvTPS55, VvTPS59) and several transcription factors were associated with terpenoids metabolism. Based on soluble solids and OAV results, T18–T22 period (18–22 weeks post-flowering) can become good quality on-vine storge berries. The gene expression profile and developmental patterns of metabolites in MEP pathway may helpful in functional characterization of candidate genes related to terpenoid metabolism in future studies. Full article

Between 2022 and 2024, a severe branch dieback disease was observed affecting over 6% of sweet cherry trees of the ‘Tieton’ cultivar in commercial greenhouses in southern Liaoning Province, China. Symptoms primarily occurred at the top of young branches. At the early stage of disease onset, the lesions appeared as dark brown, irregularly shaped areas with a moist surface; as the disease progressed, these lesions turned dry and rotten, leading to tree decline symptoms in sweet cherry trees. Disease diagnosis was carried out in sweet cherry greenhouses across Liaoning Province, where 24 diseased samples were collected and 14 fungal isolates were obtained therefrom. Based on morphological traits, cultural characteristics, and multi-locus phylogenetic analyses of the internal transcribed spacer (ITS) region, beta-tubulin (TUB2) gene, and translation elongation factor 1-α (TEF1) gene, these isolates were identified as Botryosphaeria dothidea. Two representative isolates, namely zdcy-1 and zdcy-2, were selected for pathogenicity assays. Both mycelial plug and spore suspension inoculation methods confirmed the pathogenicity of the pathogen. The biological characteristic assays revealed that the optimal temperature range for the pathogen’s mycelial growth on PDA medium was 25–28 °C, and the optimal pH range was 6.0–8.0. This study improves the understanding of branch dieback disease in sweet cherry orchards in China, enriches the knowledge regarding the geographical distribution, host range, and infection sites of the pathogen, and provides novel insights for the management of sweet cherry diseases. Full article

Synthetic cannabinoids (SCs) represent one of the rapidly growing groups of new psychoactive substances (NPS) on the illicit drug market. SCs mimic the effects of Δ⁹-tetrahydrocannabinol, but they have a greater affinity to the receptors, resulting in more potent psychoactive effects than traditional substances. The toxicity and high abuse potential of SCs could pose serious health risks to their users. The challenges posed by the SCs require innovative monitoring strategies like the analysis of untreated wastewater, known as wastewater-based epidemiology (WBE). In this review article, we summarized the available literature on the detection and quantification of SCs in raw wastewater samples published between 2013 and 2025. We paid special attention to challenges related to different experimental stages of WBE analysis that hinder the accurate measurement of SCs and their metabolites. The reviewed studies show that wastewater analysis reflected the dynamic evolution of the illicit SCs market. As studies on the analysis of SCs in wastewater remain scarce, large monitoring campaigns and research performed in more locations are needed. Modern analytical hyphenated systems such as LC-MS are essential for the sensitive and accurate quantification of SC biomarkers in wastewater and their sound identification. Future studies should address further stability tests, investigation of SC metabolism, and careful selection of the effective SC extraction method from the complex environmental matrix. Full article

Background: Three-dimensional (3D) facial scanning is an objective, non-invasive method for quantifying facial soft-tissue changes following complete denture (CD) rehabilitation. Reliable quantification of these changes in completely edentulous patients can support more predictable aesthetic and functional outcomes. Methods: This prospective before–after observational study included 30 completely edentulous patients (12 men, 18 women; age 48–87 years; mean ± SD: 67.8 ± 9.2 years) who received new maxillary and mandibular CDs. Structured-light 3D facial scans were obtained at baseline (edentulous, without dentures) and post-rehabilitation with dentures in place, in relaxed posture (RP) and maximal intercuspation (MI). Sixty-five validated anthropometric landmarks were analyzed. Primary outcomes were lower facial height (Sn-Gn), nasolabial angle (Cm-Sn-Ls), lower facial convexity (Ls-Li-Pg), mouth width (Ch-Ch), and upper vermilion height (Ls-Sto). Pre–post changes were assessed using paired-sample tests (p < 0.05). Results: Thirty-four of 65 parameters (52.3%) demonstrated significant post-treatment changes (p < 0.05), mainly in the perioral and lower facial regions. The reported parameters were selected due to their clinical relevance in evaluating perioral support and facial profile changes after complete denture treatment. In RP, upper lip thickness increased from 3.69 ± 0.97 mm to 4.96 ± 1.11 mm (Δ = +1.27 mm; p < 0.0001) and lower lip thickness from 6.18 ± 2.69 mm to 7.36 ± 1.52 mm (Δ = +1.18 mm; p = 0.0408). The nasolabial angle decreased from 116.08 ± 9.17° to 108.06 ± 9.56° (Δ = −8.02°; p = 0.0016). In MI, mouth width increased from 55.72 ± 3.43 mm to 57.97 ± 3.13 mm (Δ = +2.25 mm; p = 0.0102). Conclusions: Complete denture rehabilitation produces measurable, clinically relevant improvements in facial soft-tissue morphology in completely edentulous patients, particularly affecting lip support, mouth width, and the nasolabial profile. Structured-light 3D facial scanning provides a reproducible approach to objective outcome assessment and may support individualized denture design. Full article

Predation of sea turtles by jaguars (Panthera onca) in the Santa Rosa National Park (SRNP) has been well documented over the past decade. However, the factors that influence jaguar feeding behavior, including environmental factors or characteristics of the beaches and the adjacent forest, are poorly known. This study aimed to identify the relationship between vegetation density and human activity on the distribution of feeding sites of jaguar on sea turtles at nesting beaches in Santa Rosa National Park, Costa Rica. We sampled three beaches (Naranjo, Nancite, and Colorada), where we identified and registered sea turtle carcasses preyed on by jaguars between June and November 2019. Through systematic searches of the forest adjacent to the beach, we documented the species, geographic coordinates, carcass length and width, vegetation cover at the carcass site, and the average vegetation coverage corresponding to the date and beach of each sea turtle carcass. In total, we recorded 338 sea turtle carcasses preyed on by jaguars, 156 at Naranjo beach, 103 at Nancite beach, and 89 at Colorada beach. The beach with the highest average density of carcasses was Colorada (8.7 (SD = 5.42)/ha), followed by Nancite (6.06 (SD = 5.58)/ha) and Naranjo (2.64 (SD = 1.79)/ha). The dragging distance from the beach line to sea turtle carcasses was best explained by the interaction of nesting beach and canopy cover at the carcass. Our canopy cover results may reflect that jaguars select sites that better hide their prey, in the same way that green turtles (Chelonia mydas) usually prefer areas with good coverage to nest in, contrasting to the nesting behavior of olive ridleys (Lepidochelys olivacea). On beaches, higher concentrations were observed where there was less human presence and this may reflect both turtle nesting and jaguar predation activity. Full article

Pomegranate is valued for its abundant polyphenolic content and its capacity to promote health. In this study, pomegranate juice or pericarp extracts from two Mediterranean regions (Montenegro and Italy) were systematically and comparatively evaluated for the first time with respect to their polyphenolic composition, antioxidant capacity, and antimicrobial activity. The extraction of juice extracts was accomplished by means of the Kutscher–Steudel liquid–liquid extraction technique, which was employed to selectively recover phenolics. In contrast, the extraction of pericarp extracts from the solid matrix was achieved via Soxhlet extraction. A thorough high-performance liquid chromatography (HPLC) analysis was conducted to identify and quantify the major phenolic compounds present in the sample. This analysis revealed the presence of ellagitannin punicalagin isomers, with concentrations reaching up to 254.75 mg/g of the sample, as well as ellagic acid and gallic acid. The antioxidant potential of the samples was assessed using the antioxidant activity index (AAI) from the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test and by a ferric reducing antioxidant power (FRAP) assay. Juice extracts demonstrated a range of activity levels, with AAI values ranging from 0.17 to 2.12 and FRAP values ranging from 2.49 to 19.41 mmol Fe²⁺/g. In contrast, pericarp extracts exhibited notably higher activity, with AAI values ranging from 0.18 to 27.57 and FRAP values ranging from 2.99 to 372.17 mmol Fe²⁺/g. This study demonstrates the markedly higher functional potential of pericarp extracts compared to juice extracts by linking detailed phenolic profiles with bioactivity data. Antimicrobial testing, inclusive of the determination of minimum bactericidal concentration (MBC), demonstrated that certain pericarp extracts manifested bactericidal properties at low concentrations against selected clinically pertinent strains, including methicillin-resistant Staphylococcus aureus (0.109% p/v), methicillin-sensitive S. aureus (0.109% p/v), carbapenem-resistant Acinetobacter baumannii (0.109% p/v), and Escherichia coli (0.563% p/v). Candida albicans and Klebsiella pneumoniae strains exhibited minimal sensitivity to these extracts. The findings indicate that pomegranate pericarp is a valuable by-product, and they demonstrate the potential of both juice and pericarp extracts as functional ingredients. Full article

In this study, a hybrid sensor based on a defective square-truncated patch antenna (STPA) and a frequency-selective surface (FSS) was analyzed numerically and experimentally for different glucose–distilled water solutions. Here, an FSS was employed to enhance the sensitivity of the hybrid sensor. The sensing principle relies on monitoring variations in the loss tangent ($tan\delta$) and relative permittivity (${\epsilon }_r$) caused by different glucose concentrations applied to the sample under test (SUT). An open-ended coaxial probe was used to measure the complex permittivity of the solutions, which was then fitted to the Debye relaxation model. The simulated and experimental results of the novel sensor showed good agreement in a glucose concentration monitoring application. The sensor spanned the glucose range from 0 mg/dL to 5000 mg/dL, exhibiting a sensitivity of 55.44 kHz/mgdL⁻¹ and a figure of merit (FOM) of 6.23 × ${10}^{-4}$ (1/mgdL⁻¹) in the experiments and 53.60 kHz/mgdL⁻¹ and 1.71 × ${10}^{-4}$ (1/mgdL⁻¹) FOM in the simulations. When solutions with different concentrations were tested in the SUT, the resonance frequency of the antenna ($f_0$, in GHz) changed. To further characterize the sensor response, the relationship between the glucose concentration (C, in mg/dL) and $f_0$ was examined. A regression-based prediction model was constructed to map the measured scattering parameters to the glucose concentration, yielding a coefficient of determination ($R^2$) of 0.976. The high sensitivity, compact size, and compatibility with planar fabrication suggest that the proposed hybrid sensor has the potential to contribute to the development of non-invasive glucose-monitoring systems. Full article