Search Results (7,186)

This paper investigates the global polynomial synchronization (GPS) problem for quaternion-valued neural networks (QVNNs) featuring proportional delay, parameter uncertainty, and external disturbance. A combined approach of sliding mode control (SMC) and a non-separation strategy is adopted to achieve this goal. First, an integral-type sliding surface is designed for the system. Then, by constructing a delay-free Lyapunov functional and leveraging the properties of the quaternion vector norm and inequality techniques, sufficient conditions are derived to achieve GPS for the sliding mode dynamics. Furthermore, both a SMC law and an adaptive SMC law are designed, with a reachability analysis confirming that the system trajectories reach the predefined sliding surface in finite time. Finally, numerical examples with graphical analysis are provided to verify the obtained results, along with their application in color image pattern storage and retrieval. Full article

The still-growing demand for nutritious gluten-free products necessitates the development of a composite flour that addresses the nutritional deficiencies common in conventional gluten-free formulations. This study aimed to comprehensively characterize brown teff (Eragrostis tef (Zucc.) Trotter) and soybean (Glycine max (L.) Merr.) composite flours at 0%, 10%, 20%, 30%, and 40% soybean inclusion levels (w/w) to establish evidence-based formulation guidelines for future products. Proximate composition, antioxidant properties (total polyphenol content—TPC, antioxidant capacity vs. 2,2-diphenyl-1-picrylhydrazyl radical—DPPH and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid radical—ABTS, ferric reducing antioxidant power—FRAP), particle size distribution, pasting properties, color characteristics, and molecular fingerprints (Fourier transform infrared spectroscopy—FTIR) were evaluated. A principal component analysis (PCA) was employed to identify compositional–functional relationships. Soybean inclusion significantly enhanced protein content from 9.93% (pure teff) to 23.07% (60:40 blend, dry matter), fat from 2.14% to 10.47%, and fiber from 3.43% to 6.72%. The antioxidant capacity increased proportionally with soybean content, with a 40% inclusion yielding FRAP values of 5.19 mg FeSO₄/g DM and TPC of 3.44 mg GAE/g DM. However, pasting viscosity decreased notably from 12,198.00 mPa·s (pure teff) to 129.00 mPa·s (60:40 blend), indicating a reduced gel-forming capacity caused by soybean addition. PCA revealed that nutritional composition (PC1: 70.6% variance) and pasting properties (PC2: 21.0% variance) vary independently, suggesting non-additive functional behavior in blends. Brown teff–soybean blends at a 20–30% soybean inclusion optimize the balance between protein enhancement, antioxidant preservation, and the maintenance of functional properties suitable for traditional applications, providing a nutritionally superior alternative for gluten-free product development. Full article

The present study analyses the changes in antioxidative behavior of biodegradable Poly(lactic acid) (PLA)-based composite films with bioactive additives derived from pomegranate peel, an abundant agricultural by-product rich in antioxidants and antimicrobials. PLA-based composites were prepared by incorporating industrial-grade pomegranate peel powder (PoP) via melt extrusion at concentrations of 1–5 percent by weight (wt.%). For mechanical characterization, the resulting films were subjected to tensile testing. Their thermal properties were further characterized using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic oxidation induction temperature measurements (OIT), complemented by Fourier-transform infrared spectroscopy (FT-IR), color analysis, rheology, scanning electron microscopy (SEM), and UV-Vis spectroscopy. Results show that the incorporation of PoP had no significant impact on the characteristic transition temperatures (Tg, Tm, and Tc) of PLA, indicating that the thermal behavior of the polymer matrix was largely preserved. However, while the thermo-oxidative stability of PLA was improved in the presence of PoP, with a maximum at 3 wt.% of PoP, increasing the OIT by 30 °C, the mechanical performance of the composite films was adversely affected, as evidenced by decreased tensile strength and elongation at break indication embrittlement, especially for ≥3 wt.% of PoP. Significant changes were observed in the films’ surface properties, as well as in their color parameters and UV transmittance values. Consequently, while PoP offers potential bioactive functionality for use as a sustainable additive, its content must be carefully optimized to maintain an acceptable balance between functionality and mechanical integrity. Full article

Body color is the most prominent phenotypic trait in animals. To investigate the molecular regulatory mechanisms underlying skin pigmentation and body color in Channa argus, single-nucleus RNA sequencing technology was employed to analyze cell diversity and functional changes in the skin of normal and albino C. argus. Three pigment-related cell types, seven immune-related cell types, and nine other skin-related structural and functional cell types were identified. The skin of albino C. argus, which appears white to the naked eye, contains numerous melanocytes and iridophores with reflective silver properties. Compared to normal C. argus, melanocytes in albino individuals contained fewer melanin granules, while iridophores exhibited increased chromogenic substances. Melanocyte-specific genes—kitlg, myo5a, and scarb1—were significantly downregulated in albino melanocytes (p < 0.05). Conversely, iridophore-specific genes alk, pnp, and gpnmb were significantly upregulated in albino skin, whereas mlph was significantly downregulated (p < 0.05). Weighted gene co-expression network analysis revealed that scarb1 was associated with the melanocyte module, alk was identified as a core gene, and pnp was linked to the iridophore module. Functionally, scarb1 is involved in pigment transport, pnp in purine synthesis, and alk is essential for iridophore development. Therefore, scarb1, pnp, and alk may be correlated to albinism in C. argus. Overall, this study constructed a single-cell transcriptional atlas of C. argus skin, providing valuable reference data for further research into the regulatory mechanisms governing body color formation and maintenance in this species. Full article

Seed coat color in peanut (Arachis hypogaea L.) is a critical agronomic trait that affects both nutritional quality and market appeal. In this study, we identified two bHLH transcription factor genes, AhWSC1a and AhWSC1b, homologues of Arabidopsis TRANSPARENT TESTA 8, as indispensable gatekeepers of basal flavonoid pigmentation. QTL-seq analysis of a recombinant inbred line population derived from a black-testa parent (S3) and a white-testa parent (S2) revealed that recessive loss-of-function mutations in both AhWSC1a/1b abolish proanthocyanidin biosynthesis, resulting in a white testa. Integrated metabolomic and transcriptomic profiling confirmed the absence of proanthocyanidins and a strong repression of late anthocyanin-pathway genes (DFR, LDOX) in the mutants. Molecular assays further demonstrated that AhWSC1 physically interacts with the R2R3-MYB regulator AhTc1 to form a functional MBW complex that activates AhDFR and AhLDOX transcription. In this research, we also found that the black testa phenotype may arise from elevated AhTc1 expression associated with a structural variant (SV); however, in the SV background, the introduction of ahwsc1a/1b mutant leads to a significant suppression of AhTc1 expression. Notably, because AhWSC1 is transcriptionally silent in hairy-root systems, overexpression of AhTc1 alone failed to induce these late-stage anthocyanin biosynthesis genes, highlighting AhWSC1 as an indispensable, rate-limiting hub of anthocyanin biosynthesis pathway regulation. Collectively, our findings establish AhWSC1a and AhWSC1b as master regulators of peanut testa pigmentation, elucidate the molecular basis of classical white testa inheritance, and provide genetic targets for precision-breeding of nutritionally enhanced cultivars. Full article

Intraoperative assessment of pancreatic quality, followed by sampling for the potential isolation of Langerhans islets for subsequent autotransplantation, is currently a key component of post-total pancreatectomy diabetes mellitus treatment. The aim of this study was to quantitatively evaluate pancreatic parenchymal stiffness using optical coherence elastography (OCE) imaging, and to investigate the utility of the OCE method as a potential indicator of islet yield after pancreatectomy. A total of 41 freshly excised human pancreatic specimens, containing pancreatic ductal adenocarcinoma (PDAC) and surrounding non-tumorous tissues post-pancreatectomy, were studied. In this research, the stiffness (Young’s modulus, kPa) and its color-coded 2D distribution were calculated for various pancreatic samples using compression OCE. Stiffness values were compared between intact pancreatic parenchyma (islet-poor and islet-rich) and pancreatic lesion groups (parenchymal fibrosis and/or PDAC invasion). The data were confirmed by histological analysis. In addition, the measured stiffness values for various morphological groups of the pancreatic samples were compared with the number of isolated islets obtained from pancreatic samples after collagenase treatment. The study demonstrated that OCE can effectively distinguish areas of pancreatic lesions and identify intact pancreatic parenchyma containing Langerhans islets. A highly significant increase in mean stiffness (p < 0.0001) was observed in postoperative pancreatic samples exhibiting signs of parenchymal fibrosis or PDAC invasion compared to unaffected, intact pancreatic parenchyma. For the first time, a relationship between stiffness values and the number of isolated pancreatic islets was demonstrated; in particular, the number of isolated islets significantly decreased (≤110 pcs/g) in samples exhibiting stiffness values above 150 kPa and below 75 kPa. The optimal stiffness range for the efficient isolation of islets (≥120 pcs/g) from pancreatic tissue was identified as 75–150 kPa. The study introduces a novel approach for rapid and objective intraoperative assessment of pancreatic tissue quality using real-time OCE data. This technique facilitates the identification of regions affected by pancreatic lesions and supports the selection of intact pancreatic parenchyma, potentially enhancing the accuracy of Langerhans islet yield predictions during surgical resection. Full article

This study presents the first comprehensive physicochemical and bioactive characterization of the fruit of Chondrodendron tomentosum Ruiz & Pav. (Menispermaceae). Biometric and physicochemical parameters were characterized across three fruit ripening stages (green, turning, ripe). Additionally, proximate composition was determined in ripe fruits, and methanol concentration (25–75%), ultrasonic amplitude (30–70%), and time (1–15 min) were optimized using response surface methodology with a Box–Behnken design. During ripening, weight increased by +47.7% (3.89 to 5.74 g; p < 0.0001), TSS by +26.1% (7.00 to 8.83 °Brix), pH decreased by 32.0% (6.28 to 4.27), and acidity increased by 276% (0.25 to 0.94%). The quadratic models demonstrated high predictive accuracy (R² > 96.5%; p < 0.004). Optimal conditions (57% methanol, 70% amplitude, and 15 min) maximized total anthocyanin content (120.71 ± 1.89 mg cyanidin-3-glucoside/L), total phenols (672.46 ± 5.84 mg GAE/100 g), and DPPH radical scavenging capacity (5857.55 ± 60.20 µmol Trolox/100 g) in ripe fruits. Unripe fruits do not contain anthocyanins, reaching 46.01 mg C3G/L in turning fruits and 120.71 mg/L in ripe fruits (162% higher than turning fruits). Principal component analysis (90.6% variance) revealed synchronized co-accumulation of anthocyanins and phenols, enhanced by vacuolar acidification. These results suggest ripe C. tomentosum fruits as a potential source for natural colorants, nutraceuticals, and functional foods, pending prior development of green, human-safe extraction processes. 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

Topaz is one of the most economically important fluorine-rich nesosilicates, which are predominantly colorless in natural crystals. Hence, the trade relies almost entirely on irradiated blue topaz with an unstable color center, which has been shown to fade over time. The cobalt (Co) diffusion treatment is a stable alternative process for converting colorless topaz to blue by a solid-state diffusion mechanism. To investigate the potential role of Co²⁺ substitution in the formation of the blue layer and the coupled behavior of F/OH dehydroxylation in facilitating this process, systematic diffusion treatments have been successfully conducted and compared. In this study, gem-quality topazes were annealed in air at 1000 °C for 20–40 h (hr) along with CoO, Fe₂O₃, Cr₂O₃, and CuO powders. The diffused products were characterized using Scanning Electron Microscope (SEM), Ultraviolet-Visible absorption spectroscopy (UV-Vis), Near-Mid Infrared spectroscopy (NMIR), and X-ray photoelectron spectroscopy (XPS). Parallel runs with CuO, Fe₂O₃, or Cr₂O₃ alone confirmed that none of these oxides produces a stable blue layer, underscoring the unique role of Co. The Co-diffused sample displays an intense blue layer characterized by a Co²⁺ octahedral isomorphism triplet at 540, 580, and 630 nm, which are absent from both untreated and heat-only controls. XPS analysis reveals the emergence of Co²⁺ (binding energy: 780.63 eV) and a concomitant depletion in F⁻, along with the disappearance of the OH overtone absorption at 7123 cm⁻¹. These observations confirm that defluorination generates octahedral vacancies accommodated by the coupled substitution: CoF₂ (solid reactant) + (AlO₂)⁻ (fragment of topaz structure) → AlOF (solid product) + (CoOF)⁻ (fragment of topaz structure). Prolonged annealing leads to decreased relative atomic percentages of K⁺ and F⁻ ions, consistent with volatilization losses during the high-temperature process, thereby directly correlating color intensity with cobalt valence state, which transfers from Co²⁺ to Co³⁺. These findings establish a Co-incorporation chronometer for F–rich aluminosilicate systems, with an optimal annealing time of approximately 20 hr at 1000 °C. Furthermore, the above results demonstrate that the color mechanism in nesosilicate gems is simultaneously governed by volatile release and cation availability. Full article

Polyaniline (PANI), characterized by its proton-coupled redox mechanism and multicolor reversibility, is widely investigated for adaptive optical interfaces. Compared to inorganic oxides, PANI offers advantages in cost-effectiveness, mechanical flexibility, and molecular tunability; however, its practical implementation faces challenges related to kinetic limitations and environmental instability. This review presents a comprehensive analysis of PANI-based electrochromic materials, examining the intrinsic correlations among synthesis methodologies, microstructural characteristics, and optoelectronic performance. Synthesis strategies, including chemical oxidative polymerization, electrochemical deposition, and template-assisted techniques, are evaluated. Emphasis is placed on resolving the trade-off between optical contrast and switching kinetics by constructing high-surface-area porous nanostructures and inducing chain ordering via functional dopants to shorten ion diffusion paths and reduce charge transfer resistance. Fundamental electrochromic properties are subsequently discussed, with specific attention to degradation mechanisms triggered by environmental factors, such as pH drift, and stabilization strategies involving electrolyte engineering and composite design. Furthermore, the review addresses the evolution of applications from single-band monochromatic displays to dual-band smart windows for decoupled visible/near-infrared regulation and multifunctional integrated systems, including electrochromic supercapacitors and adaptive thermal management textiles. Finally, technical challenges regarding long-term durability, neutral color development, and large-area manufacturing are summarized to outline future research directions for PANI-based optical systems. Full article

This study investigated the effects of alkaline pretreatment and drying methods on the physicochemical properties of Gelidium amansii and the quality of the resulting agar jelly. Seaweeds with or without alkaline pretreatment were subjected to either sun-drying or shortwave infrared (SWIR) lamp-drying for three or seven cycles to evaluate whether SWIR drying could replace conventional sun-drying by reducing drying time and whether alkaline pretreatment could enhance gel hardness. The results showed that both drying methods effectively reduced moisture content, while the alkaline pretreatment significantly increased the ash content, likely due to the removal of water-soluble components. Marked color improvement was observed after seven cycles of sun-drying or following alkaline pretreatment, with the appearance changing from purplish red to bright golden yellow, which is closer to traditional quality expectations. Although SWIR lamp-drying was more energy-efficient, it resulted in limited color improvement. Volatile compound analysis revealed that deviations from the fresh control increased with the number of sun-drying cycles, whereas alkaline pretreatment and infrared-drying induced more pronounced changes in volatile profiles. Among all of the treatments, Gelidium subjected to seven sun-drying cycles produced jellies with the most favorable texture, indicating enhanced agar gel formation through repeated washing and drying. In contrast, the combination of alkaline pretreatment and infrared-drying restricted agar extraction, likely due to tissue hardening and insufficient light intensity, resulting in weak or negligible gel formation. Overall, both the drying method and alkaline pretreatment significantly influenced the Gelidium quality and agar gel properties; despite being labor-intensive, traditional washing and sun-drying processes remain critical for achieving desirable product quality. Full article

The increasing global demand for sparkling wines has encouraged the exploration of alternative grape varieties and emerging production regions. This study evaluated the potential of three indigenous Romanian grape varieties (Fetească regală, Tămâioasă românească, and Fetească albă) for sparkling wine production using the méthode champenoise, with grapes sourced from the ullu Mare region. The wines were characterized at two aging intervals (9 and 36 months on lees), with analyses performed on both disgorged and undisgorged samples to assess changes in physicochemical parameters, color attributes, volatile composition, and sensory properties. All varieties exhibited relatively high acidity (6.12–6.53 g/L), particularly Fetească regală (6.37–6.53 g/L), supporting their suitability for sparkling wine production. Extended lees aging enhanced the development of complex tertiary and quaternary aromas while preserving intrinsic floral and fruity attributes. Volatile analysis revealed aging-related increases in higher alcohols and medium-chain fatty acids, with 1-pentanol reaching 106.8 mg L⁻¹ and octanoic acid increasing from approximately 4.2 to 7.9 mg L⁻¹ after 36 months. Principal component analysis explained over 70% of the total variance, discriminating wines according to grape variety and maturation time. This study aimed to provide a detailed characterization of these sparkling wines, integrating physicochemical, chromatic, volatile, and sensorial analyses to evaluate their quality and enological potential. Full article

High-performance nylon 6,6 webbings used in critical applications degrade under solar exposure, necessitating reliable methods to assess their residual strength non-destructively. This study investigates the feasibility of using instrumental color change as a predictive indicator for the loss of breaking strength. Four colors of nylon 6,6 webbings were subjected to accelerated xenon-arc solar weathering for up to 15 days. The resulting color change was quantified using both the CIELab and CIEDE2000 formulas, and residual breaking strength was measured following ASTM D6775. A regression analysis was performed to correlate these properties. The results demonstrate that a strong predictive relationship exists, but its efficacy is highly color-dependent. Webbing with high initial chroma, namely tan (R² = 0.889) and navy (R² = 0.817), showed a strong correlation between color change and strength loss. In contrast, the models for low-chroma black and white webbings were weak and unreliable. Furthermore, the simpler CIELab (ΔE*_ab) formula provided slightly more accurate predictions than the more complex CIEDE2000 (ΔE*₀₀) metric. It is concluded that colorimetry can be a viable non-destructive tool for predicting mechanical degradation, but its application is limited to specific high-chroma materials, precluding a universal model based entirely on colorimetry. Full article

Capsicum pubescens (rocoto) is an Andean domesticate with notable agronomic and nutraceutical potential, yet it remains underrepresented in chili pepper breeding programs. In this study, 78 accessions from the Peruvian Andes were evaluated in a single field environment during the 2024 growing season for 28 variables spanning plant architecture, phenology and yield, color (CIELAB), weight, fruit morphology, physicochemical variables, and functional phytochemicals, including total phenolics, carotenoids, ascorbic acid, capsaicinoids, and antioxidant activity (FRAP, DPPH, ABTS). Descriptive analyses revealed broad phenotypic diversity in key variables such as yield and bioactive compounds. Spearman correlations uncovered a clear modular structure, with strong within-domain associations across morphological, chromatic, and biochemical variables, and statistically significant but low-magnitude cross-domain associations (e.g., fruit length with pungency, redness with total phenolics). Principal component analysis and hierarchical clustering resolved three differentiated phenotypic profiles: (i) low-pungency accessions with high soluble solids and varied fruit colors; (ii) highly pungent materials with elevated antioxidant capacity; and (iii) large, red-fruited accessions with considerable carotenoid content and high moisture. This multivariate architecture revealed weak cross-block correlations among agronomic, color, and functional traits, enabling selection of promising accessions combining desirable agronomic attributes and favorable bioactive profiles in specific accessions. These results provide a quantitative foundation for future breeding strategies in C. pubescens, opening concrete opportunities to develop improved cultivars that simultaneously meet productivity and functional quality criteria. Full article

Reticuloendotheliosis virus (REV) is an immunosuppressive virus in poultry that can cause acute reticular neoplasms, chronic lymphoid tumors, stunting syndrome, and secondary infections. In many countries, the lack of effective vaccines has resulted in a high prevalence of REV infections and substantial economic losses. Enzyme-linked immunosorbent assay (ELISA)-based antibody detection is an important tool for monitoring the REV prevalence in poultry farms. ELISA coating antigens generally consist of either whole virus or viral protein; however, most commercially available REV antibody ELISA detection kits use whole virus as the coating antigen, which limits their applicability in certain diagnostic and research settings. In this study, the gp90 protein from a dominant REV strain was expressed and purified using 293F suspension cell eukaryotic expression system. Using recombinant gp90 protein as the coating antigen, an indirect ELISA for detecting gp90 antibodies (gp90-ELISA) was developed. After optimization, the optimal conditions were as follows: coating antigen concentration of 4 µg/mL with overnight incubation at 4 °C; blocking with 5% skim milk at 37 °C for 1.5 h; serum dilution of 1:200 with incubation at 37 °C for 45 min; secondary antibody dilution of 1:1000 with incubation at 37 °C for 30 min; and color development using TMB substrate at room temperature in the dark for 10 min. The cut-off value was defined as an OD₄₅₀ ≥ 0.22 for positive samples and < 0.22 for negative samples. The developed gp90-ELISA specifically detected REV-positive sera at a maximum serum dilution ratio of 1:3200. Intra- and inter-assay variation coefficients were ≤10%, indicating that the gp90-ELISA had good specificity, sensitivity, and reproducibility. Laboratory serum testing showed that the gp90-ELISA successfully detected sera from chickens immunized with the gp90 protein or infected with REV. Furthermore, analysis of clinical serum samples demonstrated 100% concordance between the gp90-ELISA results and a commercial whole-virus-coated ELISA kit. These results indicate that the gp90-ELISA is a reliable supplementary method to whole-virus-coated ELISA and has potential utility in disease surveillance and evaluation of immune responses. Full article