Search Results (1,968)

Papaver rhoeas L. has four strikingly red petals with a distinctly black area bordered by a thin white line at the petal base, thus creating a color pattern that makes the center of the flower, where the pollen is located, visually stand out. This paper aims to assess the intra-petal spatial variability in P. rhoeas petal color intensity and hue and associate it with corresponding differences in the amount and type of petal pigments. The distribution of pigments in the petal epidermis was investigated in different petal segments by column chromatography. Fresh petals were extracted with deionized water during blooming, between April and June 2023, in northwestern Greece. UV–visible absorption spectra of the eluted fractions revealed five pigments, with each pigment belonging to a different elution zone. In the black spots of the petals, anthocyanin coexists with a yellow flavonol with a maximum absorption peak at 340 nm. Red petal extract in 70:30 ethanol–water showed a distinct negative Cotton effect at 284 nm, distinct from black segment extract with a negative Cotton effect at 227 nm. The uneven distribution of floral pigments along the petal epidermis creates a unique color palette, enabling UV-reflection, which is key in attracting pollinators responsible for plant reproduction. Full article

Beryl is classified as a cyclosilicate mineral, and its color is primarily determined by the type and oxidation state of trace elements. In this study, natural yellow-green beryl was used as the research subject, and heat treatment experiments were performed at various temperatures under both oxidizing and reducing atmospheres. A combination of analytical techniques, including electron probe microanalysis (EPMA), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and ultraviolet-visible spectroscopy (UV-Vis), were employed to systematically investigate the composition, structure, and chromogenic mechanisms of beryl before and after heat treatment. The experimental results indicate that heat treatment under both atmospheres can lead to the transformation of yellow-green beryl into blue, with 500–600 °C under a reducing atmosphere identified as the optimal treatment condition. With increasing temperature, beryl gradually dehydrates, resulting in a faded blue color and reduced transparency. Even after treatment at 700 °C, no significant changes in unit cell parameters were observed, and both type I and type II water were retained, indicating that the color change is not attributed to crystal structure transformation or phase transitions. The study reveals that the essential mechanism of color modification through heat treatment lies in the valence change between Fe²⁺ and Fe³⁺ occupying channel and octahedral sites. The observed color variation is attributed to changes in absorption band intensity resulting from charge transfers of O²⁻ → Fe³⁺ and Fe²⁺ → Fe³⁺. This study provides theoretical insights and technical references for the color enhancement of beryl through heat treatment. Full article

To achieve dual functionality that can monitor both Al³⁺ levels in food and the freshness of fish, rice straw fibers (RSFs) were treated in NaOH solutions and then cationized with 2,3-epoxypropyltrimethylammonium chloride, onto which alizarin red S molecules were immobilized through electrostatic interaction to develop a smart felt-like label. An optimized treatment in 5 wt% NaOH solution effectively removed lignin and hemicellulose, facilitating quaternary ammonium group grafting and stable ARS anchoring. The ARS@BRSF-5NaOH exhibited high pH sensitivity, showing visually discernible color changes (ΔE > 5, perceptible to the naked eye) under acidic (pH ≤ 6) and strongly alkaline (pH > 12) conditions. During the storage of the fish, the label transformed from yellow to dark purple (ΔE increase) as TVB-N levels approached 20 mg/100 g, enabling real-time freshness monitoring for protein-rich products. Additionally, the label achieved a detection threshold of 1 × 10⁻⁵ mol·L⁻¹ for Al³⁺ through a coordination-induced chromatic transition (purple to pale pink). This research highlights the feasibility of utilizing an agricultural waste-derived material to develop cost-effective, visually responsive, dual-functional intelligent labels for food safety, offering significant advancements in on-site quality assessment. Full article

Gibberellic acid (GA₃) and forchlorfenuron (CPPU) are widely used plant growth regulators for promoting berry enlargement in grapes. To evaluate the effects of GA₃ and CPPU on fruit quality and peelability of the seedless grape cultivar ‘Wuhe Cuibao’, and to determine the optimal concentration combination under the ecological conditions of Jinzhong, Shanxi Province, grape clusters were treated with varying concentrations of GA₃ and CPPU at full bloom and again 14 days later (young fruit stage), with water treatment as the control (CK). After maturation, the fruits were harvested for subsequent analysis of external morphology and internal quality parameters in both fruit clusters and individual berries. Paraffin embedding and sectioning were performed to conduct histological observations of cuticle thickness and cellular morphology in the treated fruits. The results indicate that GA₃ and CPPU treatments significantly enhanced the external quality of ‘Wuhe Cuibao’ grapes by effectively reducing fruit drop during cultivation. With the exception of T3 treatment, all treatments promoted both cluster elongation and berry enlargement. GA₃ treatment alone was more effective than CPPU treatment, and its effects were positively correlated with concentration. The T2 treatment resulted in the greatest increases in fruit length, berry weight, pedicel thickness, and pedicel tensile strength, surpassing the control (CK) by 35.53%, 43.65%, 88.92%, and 104.76%, respectively. The combined application of GA₃ and CPPU showed a synergistic effect, especially in T8, which led to the highest increases in cluster length (21.94%), cluster weight (41.92%), and berry width (13.49%) compared with the control. In addition, all treatments promoted the color transition of berries from green to yellow-green. Histological analysis showed a significant increase in cuticle thickness and in the size of both epidermal and subepidermal cells after treatment. In addition, all treatments increased fruit firmness and peel adherence in a concentration-dependent manner. GA₃ treatment alone produced the greatest increases in both fruit firmness and peel–flesh adherence, while the addition of CPPU treatment alleviated these effects. All treatments improved internal fruit quality by increasing the content of vitamin C, reducing sugars, soluble sugars, starch, and cellulose. GA₃ treatment alone significantly increased the levels of soluble solids, soluble proteins, and total phenols by 5.67%, 1.49%, and 5.38%, respectively, compared to the control (CK). In contrast, CPPU treatment alone significantly reduced the levels of these compounds. Notably, combined GA₃ and CPPU treatment in T5 led to the highest accumulation of vitamin C and reducing sugars, with increases of 3.78% and 62.36%, respectively, compared to the CK. Additionally, all treatments reduced anthocyanin and titratable acid levels, with a synergistic effect observed under combined treatment in lowering titratable acidity. Comprehensive evaluation revealed that the combined application of 50 mg·L⁻¹ GA₃ and 5.0 mg·L⁻¹ CPPU at full bloom and 14 days thereafter resulted in the greatest overall improvement in grape quality, offering theoretical and practical support for the efficient, high-quality cultivation of this cultivar. Full article

Rye exhibits high diversity in grain coloration among small cereals, which is mainly linked to the presence of colored flavonoids synthesized in the outer layers of the kernel. This variability is not yet sufficiently described from colorimetric, cytological, and biochemical points of view. In this study, the localization of flavonoid pigments, anthocyanins and proanthocyanidins (PAs), was analyzed across different grain tissues in 26 rye lines with identified anthocyanin grain color genes. Grain coloration was objectively characterized using the CIELAB color coordinates and the GrainScan software for image analysis of individual grains. The distribution of anthocyanins and PAs was investigated through light microscopy and matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) on longitudinal and cross sections of the grains. The results revealed that violet-grained lines accumulate anthocyanins in the pericarp, while green-grained lines contain anthocyanins in the aleurone layer. MALDI-IMS confirmed the presence of specific anthocyanins: cyanidins in the pericarp of violet-grained lines and delphinidins in the aleurone layer of green-grained lines. All studied lines, except for the anthocyanin-less vi3 mutants, exhibited PAs in the brown-colored testa. Four main color groups of the rye grains (yellow, green, brown, and violet) could be clearly differentiated using the CIE color coordinate h°. Full article

As an essential component of the built environment, outdoor artificial lighting at night, has a profound impact on visitors’ experience quality. Research on the light environment extends beyond visual effects to encompass broader psychophysiological impacts, such as perception, emotion, and public health. Shooting tree lights (STLs) are a distinctive type of outdoor lighting, commonly installed in landscape environments. This study aims to investigate the effects of different colors (yellow, red, green, and blue) of STL on alertness at night. Sixty participants took part in an experimental design assessing the impact of four different colors on electroencephalogram (EEG) and self-reported alertness. Our results indicate that STL color is a significant factor influencing physiological alertness levels. Exposure to yellow light reduced beta power, diminished alertness, and enhanced relaxation and comfort compared to red, blue, and green light. The study also identified variations in alertness based on age and gender. With respect to age, younger individuals exhibited greater alertness, while women were more alert than men. This study suggests that yellow light is generally more favorable than other colors in enhancing subjective light comfort. These findings underscore the importance of prioritizing yellow-colored STLs in landscape planning and design to promote relaxation and comfort for nighttime visitors. Full article

With the rising trend of health-conscious consumers, demand for gluten-free alternatives is increasing, and rice flour is a promising gluten-free alternative for chicken batter. This study examines the effects of particle size variations in Baromi-2 rice flour on batter rheology and the quality attributes of deep-fat fried chicken. Baromi-2 is a rice variety specifically developed to meet the demands of the modern food processing industry, especially for applications requiring dry milling. Five particle sizes (60, 100, 120, 160, and 180 mesh) were evaluated on the basis of their physicochemical properties, including water-holding capacity (WHC), amylose content, and damaged starch levels. Batter consistency was assessed and frying performance was analyzed with regard to coating pickup, cooking loss, moisture content, crust color, and textural attributes. Results demonstrated that finer particle sizes (e.g., 180 mesh) exhibited high WHC and batter viscosity, resulting in reduced flowability and enhanced adhesion. These properties contributed to high coating pickup, improved moisture retention, and reduced cooking loss during frying. Fried chicken prepared with finer particles showed soft textures, great cohesiveness, and light crust colors with high lightness (L*) and reduced redness (a*) and yellowness (b*), producing a visually appealing product. By contrast, larger particle sizes (e.g., 60 mesh) resulted in low viscosity, uneven coatings, and high cooking loss. This study highlights the critical role of rice flour particle size in optimizing batter functionality and improving the quality of fried foods. Furthermore, these findings suggest the potential to bridge the gap between consumer demand for healthier fried foods and the food industry’s demands. Full article

Monitoring salt marsh vegetation in the Yellow River Delta (YRD) wetland is the basis of wetland research, which is of great significance for the further protection and restoration of wetland ecological functions. In the existing remote sensing technologies for wetland salt marsh vegetation classification, the object-oriented classification method effectively produces landscape patches similar to wetland vegetation and improves the spatial consistency and accuracy of the classification. However, the vegetation classes of the YRD are mixed with uneven distribution, irregular texture, and significant color variation. In order to solve the problem, this study proposes a fine-scale classification of dominant vegetation communities using color-enhanced aerial images. The color information is used to extract the color features of the image. Various features including spectral features, texture features and vegetation features are extracted from the image objects and used as inputs for four machine learning classifiers: random forest (RF), support vector machine (SVM), k-nearest neighbor (KNN) and maximum likelihood (MLC). The results showed that the accuracy of the four classifiers in classifying vegetation communities was significantly improved by adding color features. RF had the highest OA and Kappa coefficients of 96.69% and 0.9603. This shows that the classification method based on color enhancement can effectively distinguish between vegetation and non-vegetation and extract each vegetation type, which provides an effective technical route for wetland vegetation classification in aerial imagery. Full article

Using agro-industrial byproducts as functional ingredients represents a sustainable approach to food development. This study aimed to characterize the physicochemical and techno-functional properties of grape marc flour and evaluate the metabolite content and antioxidant activity of the extract obtained from these residues. Grape marc flour analysis included pH, color, and techno-functional parameter assessment. The metabolite content and antioxidant activity of the extracts were determined in vitro and in a meat system. The grape marc flour exhibited low pH, lightness (L*), and yellowness (b*) index values, as well as increased redness (a*) values. It also showed the ability to retain water and oil, along with notable swelling capacity. The extracts exhibited high levels of phenolic, tannins, flavonoids, and chlorogenic acid, as well as anti-radical activity and reducing power. When incorporated into a cooked meat system, the extracts decreased pH and lipid oxidation levels. These findings suggest that grape marc flour has potential as a functional ingredient in the formulation of meat products. Full article

This paper focuses on the study of the arena wall decoration in the amphitheater at the archaeological site of Viminacium. The architectural characteristics of the amphitheater, along with the spectacle iconography, have made this finding one of the most interesting discoveries at Viminacium, as well as in a wider context. A multidisciplinary approach that included an iconographic and archaeological study, as well as Energy Dispersive X-ray Fluorescence (EDXRF), X-ray Powder Diffraction (XRD), and Raman and Fourier-transform Infrared (FTIR) spectroscopy analysis, was applied to determine the palette of the pigments used for the arena wall decoration and understand the iconography and its context in more detail. Among the commonly used earth pigments (yellow, red, brown, and green colors), copper-based pigments (green and blue Egyptian blue), and the most precious ones for the period—namely, cinnabar and lapis lazuli—were identified. The applied analytical techniques enabled a tentative suggestion of the origin of the raw materials of some of the pigments that were used, such as marine sediments or rocks from different destinations. Due to the fact that the Viminacium amphitheater constitutes a typical example of a provincial building reserved for public spectacles, the results of this study will significantly contribute to our understanding of the function of the amphitheaters in the Danubian region, as well as throughout the Roman world. Full article

By incorporating microcapsules with self-healing properties into the coating, a self-healing coating can be obtained, which can repair cracks or damage. In this study, chitosan–sodium tripolyphosphate-coated tung oil microcapsules 1# and 2# with a high encapsulation efficiency were incorporated into a UV-cured topcoat on cherry wood surfaces at different ratios. The results showed that as the microcapsule content increased, the coating’s reflectivity and gloss loss increased, while its impact resistance improved. However, the coating’s adhesion and hardness decreased. The coating containing 6% microcapsule 1# exhibited optimal performance on cherry wood board. The reflectance of the ultraviolet–visible light of the coating was 41.14%, the lightness value was 58.35, the red-green value was 13.96, the yellow-blue value was 25.32, the color difference was 4.47, the gloss reduction rate was 66.84%, the roughness was 1.11 μm, the impact resistance grade was level 4, the adhesion was level 1, the hardness was 3H, and the recovery rate was 17.06%. Comparative analysis revealed that both the chitosan/arabic gum-encapsulated tung oil microcapsules and chitosan–sodium tripolyphosphate-coated tung oil microcapsules could impart self-healing functionality to UV-cured coatings when incorporated into the finish. Notably, the coating system containing 6% chitosan/arabic gum-encapsulated tung oil microcapsules demonstrated optimal performance characteristics when applied to cherry wood substrates. The research findings demonstrate the technical feasibility of achieving self-healing functionality in UV-cured coatings for cherry wood surfaces. Full article

The toxicity of lead in conventional perovskites and their inherent chemical instability impede the commercialization of perovskite-based optoelectronics. Therefore, it is vital to develop chemically stable and environmentally friendly Pb-free alternatives. Recently, zero-dimensional (0D) all-inorganic Cs₂ZnCl₄ doped with Sn(II) has emerged as a promising candidate, exhibiting superior chemical robustness, minimal biotoxicity, and exceptional optoelectronic properties. In this work, pressure effects on structure and optical properties in Sn(II)-doped all-inorganic zero-dimensional halide perovskite are investigated both experimentally and theoretically. The structure–property relationship of Sn(II)-doped Cs₂ZnCl₄ is studied using high-pressure techniques. Piezochromism, accompanied by a remarkable change in emission color from orange/red and green to orange/yellow, was obtained from 1 atm to 22.5 GPa. Angle dispersive synchrotron X-ray diffraction (ADXRD) patterns and Raman spectra manifest that the material underwent an isostructural phase transition followed by amorphization with increasing pressure. The piezochromism and band gap engineering originate from the pressure-induced lattice compression and isostructural phase transition. This work advances STE emission studies and provides a robust strategy to boost emission efficiency and to construct multifunctional materials with piezochromism in environmentally friendly perovskites, thus facilitating diverse future applications. Full article

This study aimed to assess how sex and age influence the physicochemical and technological properties of the longissimus thoracis et lumborum muscle in Botucatu rabbits. Ten samples were used from each experimental group (females and males 3 and 12 months old). Color (L*, a*, and b*), pH, water-holding capacity, cooking weight loss, shear force, percentage of collagen (soluble, insoluble, and total), myofibrillar fragmentation index, sarcomere length, cholesterol concentrations, lipid oxidation, and chemical composition were evaluated. Sex influenced (p < 0.05) the chemical composition of the meat; young females presented meat with a higher concentration of lipids and cholesterol than males of the same age; however, the opposite results were obtained with the meat of 12-month-old rabbits. Age also influenced the meat’s characteristics: older rabbits had meat with more intense red and yellow colors and longer sarcomere length. In terms of chemical composition, 12-month-old rabbits had higher protein and lower soluble collagen and mineral matter compared to younger rabbits. Overall, age impacted the physicochemical properties, with older rabbits exhibiting more opaque, reddish meat, higher insoluble collagen, and lower moisture content. In addition, the influence of sex, especially on the chemical composition of meat in rabbits, must be emphasized. Full article

This study explores the sustainable extraction and application of natural dyes from figs (Ficus carica) and Eucalyptus leaves using an aqueous alkaline medium. The dyeing process was optimized for cotton fabric using the exhaust-dyeing method. Fabrics dyed with Ficus carica extract and its blend with Eucalyptus exhibited enhanced color strength, excellent crocking fastness (rated 4–5), and good washing fastness (rated 3–4 on the gray scale). The use of Aloe barbadensis Miller as a bio-mordant significantly improved dye fixation, resulting in deeper, earthy shades, such as green, yellow–green, and yellowish brown. The highest K/S value (5.85) was recorded in samples treated with a mordant, sodium chloride (NaCl), and the combined dye extracts, indicating a synergistic effect among the components. Mosquito repellency tests revealed that treated fabrics exhibited up to 70% repellency, compared to just 20% in undyed samples. Antibacterial testing against E. coli showed that dyed fabrics achieved over 80% bacterial reduction after 24 h, indicating promising antimicrobial functionality. Air permeability slightly decreased post-dyeing due to the potential shrinkage in cotton fabrics. Furthermore, adsorption studies showed a removal efficiency of 57% for Ficus carica dye on graphene oxide (GO) under ultrasonication. These findings confirm the potential of GO as an effective adsorbent material for treating wastewater from natural textile dyes. Overall, the study highlights the environmental safety, functional performance, and multifunctional advantages of plant-based dyeing systems in sustainable textile applications. Full article

Carboxymethyl cellulose (CMC) films, derived from sugarcane bagasse agricultural waste (SCB) incorporated with Betalains-nitrogen-doped carbon dots (Betalains-N–CQDs), derived from beet root waste (BR), offer a sustainable, smart and naked-eye sensor for strawberry packaging due to their excellent fluorescent and shape memory properties. These CMC-Betalains-N–CQDs aim to enhance strawberry preservation and safety by enabling visual detection of common food contaminants such as bacteria, fungi and Pb(II). Crucially, the CMC-Betalains-N–CQD film also exhibits excellent shape memory properties, capable of fixing various shapes under alkaline conditions and recovering its original form in acidic environments, thereby offering enhanced physical protection for delicate produce like strawberries. Optical studies reveal the Betalains-N–CQDs’ pH-responsive fluorescence, with distinct emission patterns observed across various pH levels, highlighting their potential for sensing applications. Scanning Electron Microscopy (SEM) confirms the successful incorporation of Betalains-N–CQDs into the CMC matrix, revealing larger pores in the composite film that facilitate better interaction with analytes such as bacteria. Crucially, the CMC-Betalains-N–CQD film demonstrates significant antibacterial activity against common foodborne pathogens like Escherichia coli, Staphylococcus aureus, and Candida albicans, as evidenced by inhibition zones and supported by molecular docking simulations showing strong binding interactions with bacterial proteins. Furthermore, the film functions as a fluorescent sensor, exhibiting distinct color changes upon contact with different microorganisms and Pb(II) heavy metals, enabling rapid, naked-eye detection. The film also acts as a pH sensor, displaying color shifts (brown in alkaline, yellow in acidic) due to the betalains, useful for monitoring food spoilage. This research presents a promising, sustainable, and multifunctional intelligent packaging solution for enhanced food safety and extended shelf life. Full article