Search Results (241)

Background: The present study investigated the relation between dental inclination, colorimetric variation, and aesthetic perception according to the modification of incisor inclination. Smile aesthetics, shaped by morphological factors and patient perception, are vital for social attractiveness and treatment success. This study aimed to assess the effect of varying head tilt on the perceived colour of upper central incisors by simulating changes in torque of the tooth, as well as evaluate factors influencing the perception of an aesthetic smile, including morphological characteristics and gingival aesthetic parameters. Methods: The study was comprised of three stages: colour analysis, evaluation of micro- and mini-aesthetic smile features, and an image-based assessment to determine evaluator perceptions and overall smile attractiveness. A sample of 50 students with complete, lesion-free anterior dentition was analysed. To simulate the effect of orthodontic torque changes during colour analysis, subjects tilted their heads downward and upward, representing palatal and buccal crown torque, respectively. Standardized macro-intraoral photographs were captured under controlled lighting conditions using a DSLR camera stabilized on a tripod in the different positions: the neutral head position (p0), 15° upward (p + 15), and 15° downward (p − 15). Digital colour analysis was conducted in the CIELAB colour space (L*, a*, b*). In the next stage, focusing on micro- and mini-aesthetic evaluation, an additional 50 smiles were generated using artificial intelligence via the SmileCloud program—one digitally enhanced smile per subject—complementing the initial set of 50 spontaneous smiles. These 100 smile images were evaluated by 50 laypersons and 50 dentists using a visual analogue scale via an online questionnaire, in order to assess perceptions, determine smile attractiveness, and quantify gingival aesthetic parameters. Results: The statistically significant regression results are as follows: those for the L* values in all three head inclinations: downward (−15 degrees), upward (+15 degrees), and total tilting (−15 to +15 degrees), as well as for the a* values for downward tilting and the b* values for total tilting. When the head is tilted downwards, the central incisors are positioned retrusively, and the L* b* values reveal a darker and more yellowish appearance, whereas, with the head tilted upwards, the central incisors protrude, and L* a* values indicate a brighter and more greenish appear. In the evaluation stage of the smile aesthetics study, no significant differences were observed in the judgments between laypersons and dentists or between males and females. Smiles with a high or average anterior line, parallel arc, upward lip curvature, visible first/second premolars, a smile index of 5.08–5.87, and symmetry score of 1.04 were rated as more attractive. Significant asymmetries were observed between upper dental hemi-quadrants in gingival contour and interdental papilla height, highlighting subtle morphological variations relevant to smile aesthetics. Conclusions: Aesthetic assessment revealed that the findings suggest a measurable impact of head position on dental colour perception and aesthetic evaluation. Evaluator variables including profession and gender exerted negligible effects on aesthetic perception, whereas smile attractiveness features and gingival aesthetic parameters demonstrate significant clinical applicability in patient management. Full article

Studying comprehensive performance is fundamental for the effective utilisation of broomcorn millet (Panicum miliaceum L.) germplasm resources and breeding of new varieties. However, compared with other major crops, research on broomcorn millet germplasm resources is limited, and the trait variations of broomcorn millet are unclear. In this study, three qualitative and seven quantitative traits of 933 broomcorn millet core collections were analysed to provide the basis for improving utilisation of broomcorn millet germplasm resources. The seed colour was a strong phenotypic trait and had eight variants. The 933 resources exhibited three panicle types: lateral (74.5%), scattered (18.4%), and compact (7.1%). They exhibited two inflorescence colours: green (54.7%) and purple (45.3%). Pearson’s correlation analysis revealed that 1000-seed weight significantly correlated with plant height, length of panicle, and number of main stem segments. The period of duration positively correlated with 1000-seed weight but negatively correlated with the number of uniserial panicles. Cluster analysis based on the quantitative traits indicated that all resources were divided into three groups, and each group had its respective characteristics. The analysis of core germplasm resources of broomcorn millet in this study provided a basis to explore excellent genes and for breeding of excellent varieties. Full article

Landscape quality and the productivity of $\mathit{Rhododendron\; simsii}$ are directly related to the maintenance of ecological functions in the alpine region. The specific relationship between the spatial pattern of colour patches and the visual quality of R. simsii landscape recreational forests has been insufficiently explored. In this study, we constructed a model of the relationship between landscape colour patches and the aesthetic value of such a forest, analysing the key factors driving changes in its landscape quality. A total of 1549 participants were asked to assess 16 groups of landscape photographs. The results showed that variations in perceived aesthetic quality were stimulated by colour patch dynamics and spatial heterogeneity. Utilising structural equation modelling (SEM), we identified key indicators synergistically influencing aesthetic quality, including the area percentage, shape, and distribution of colour patches, which demonstrated strong explanatory power ($R^2$ = 0.83). The SEM also revealed that the red patch area, mean perimeter area ratio, and separation index are critical latent variables with standardised coefficients of 0.54, 0.65, and 0.62, respectively. These findings provide actionable design strategies: (1) optimising chromatic contrast through high-saturation patches, (2) controlling geometric complexity, and (3) improving spatial coherence. These results advance the theoretical framework for landscape aesthetic evaluation and offer practical guidance for landscape recreational forest management. Full article

Sweet potato is a valuable root due to its nutritional benefits, health-promoting properties, and technological applications. The peel, often discarded during food processing, can be employed in the food industry, supporting a circular economy. Purple sweet potato peel (PSPP) is rich in anthocyanins, which can be used as natural colourants and antioxidants. Optimising their extraction can enhance yield and reduce costs. The current work aimed to optimize anthocyanin and antioxidant recovery from PSPP using a Box-Behnken design and sonotrode ultrasound-assisted extraction (sonotrode-UAE). Three independent variables were analysed: extraction time (2–6 min), ethanol concentration (35–85%), and liquid-to-solid ratio (10–30 mL/g). The dependent variables included total monomeric anthocyanin content (TMAC), individual anthocyanins, and antioxidant activity. TMAC in 15 extracts ranged from 0.16 to 2.66 mg/g PSPP. Peonidin-3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside was the predominant anthocyanin. Among four antioxidant assays, Ferric-reducing antioxidant power (FRAP) showed the highest value. Ethanol concentration significantly influenced anthocyanin and antioxidant recovery (p < 0.05). The model demonstrated adequacy based on the coefficient of determination and variation. Optimal extraction conditions were 6 min with 60% ethanol at a 30 mL/g ratio. Predicted values were validated experimentally (coefficient of variation <10%). In conclusion, PSPP is a promising matrix for obtaining anthocyanin-rich extracts with antioxidant activity, offering potential applications in the food industry. Full article

The aim of this study is to evaluate the effectiveness of deacidifying treatments for the restoration of textiles used as supports for works of art, with particular attention to the chemical stability, colour variation and mechanical resistance of the materials over time. The present study involved the analysis of two products: Bookkeeper^TM, containing magnesium oxide, and Nanorestore^TM, a dispersion of calcium hydroxide in alcoholic solutions of ethanol and 2-propanol. The products were applied to a series of tests on cotton, linen and jute fabrics. The experimental approach comprised an artificial degradation process of the fabrics, followed by the application of the treatments and an accelerated ageing cycle. A series of parameters were monitored throughout the experiment, encompassing surface pH, chromatic shifts ascertained through colorimetric measurements and the morphological transformations of the fabrics, as elucidated by scanning electron microscopy (SEM-EDS). The findings yielded from this study have enabled the delineation of the behaviour exhibited by the treated materials over an extended timeframe. This underscores the significance of a judicious selection of treatments, contingent upon the particular chemical and physical attributes inherent to the fabrics in question. Full article

Consumer demand for plant-based functional foods, especially probiotic beverages, has increased due to their health benefits and suitability as dairy-free alternatives. This study assessed, through a factorial combination, the stability of plant-based extracts (avocado, ginger, and tropical) individually inoculated with three commercial Lactobacillus strains (L. casei, L. plantarum, L. reuteri) and stored under refrigerated conditions during both primary (PSL) and secondary shelf life (SSL). Product shelf life was defined by probiotic viability, considering the functional threshold (≥6 log CFU/mL), which was maintained across all formulations throughout the storage period. Physicochemical parameters, including pH, titratable acidity, and colour, as well as volatile profile, remained stable, with only minor variations depending on the matrix and bacterial strain. Sensory evaluations (triangle and acceptability tests) confirmed that the probiotic juices were acceptable to consumers. Overall, the results demonstrate the feasibility of producing non-fermented, plant-based probiotic beverages that retain their functional properties and meet consumer sensory expectations, offering a promising alternative for vegan and lactose-intolerant individuals. Full article

This study explores the multifaceted aspects of sushi rice preparation, including the washing, soaking, and cooking processes and their impact on the texture, microbial, colour, and sensory properties of rice. Selenio rice, a premium short-grain rice of the Japonica variety, was analyzed for variations in amylose content and viscosity profiles. The study highlights how the rice’s compositional characteristics, particularly the amylose-to-amylopectin ratio, influence gelatinisation and cooling behaviour. The study examined washing duration, water-to-rice ratios, soaking times, and seasoning effects on product quality. The results demonstrated that washing rice for 230 s was optimal for the nigiri-forming process, while extending soaking beyond 3 min provided no additional water absorption benefits. Water temperature during soaking (10–50 °C) had minimal impact on water absorption. The addition of a vinegar mix reduced the pH to below 4.5, improving shelf life and sensory properties. During storage, textural profile analysis revealed that hardness and chewiness increased while adhesiveness decreased across all samples, with lower water-to-rice ratios resulting in firmer rice that maintained structural integrity better during storage. Sensory evaluation showed declining scores for odour, taste, texture, and overall acceptability over the 10-day storage period, though colour and appearance were less affected. Microbial loads remained relatively low across all samples during storage, and rice colour showed minimal changes over time. These findings contribute significantly to optimizing sushi rice production processes, ensuring consistent quality and desirable textural attributes throughout storage while advancing the broader fields of rice research and culinary science. Full article

The colour degradation of murals presents a significant challenge in the conservation of architectural heritage. Previous research has often concentrated on localized pigment changes while paying insufficient attention to the interaction between colour variation and indoor environmental conditions. Although non-destructive analytical techniques are widely used in heritage studies, their integrated application in combination with colourimetry has been limited, particularly in the context of Tibetan Buddhist murals in highland continental climates. This study investigates the murals of Liuli Hall in Meidai Lamasery, Inner Mongolia, as a representative case. We employed a comprehensive methodology that combines non-destructive analytical tools, gas chromatography–mass spectrometry, and quantitative colour analysis to examine pigment composition, binding material, and surface deterioration. Through joint analysis using the CIE Lab and CIE LCh colour space systems, we quantified mural colour changes and explored their correlation with material degradation and environmental exposure. The pigments identified include cinnabar, atacamite, azurite, and chalk, with animal glue and drying oils as binding materials. Colourimetric results revealed pronounced yellowing on the east and west walls, primarily caused by the ageing of organic binders. In contrast, a notable reduction in brightness on the south wall was attributed to dust accumulation. These findings support tailored conservation measures such as regular surface cleaning for the south wall and antioxidant stabilization treatments for the east and west walls. Initial cleaning efforts proved effective. The integrated approach adopted in this study provides a replicable model for mural diagnostics and conservation under complex environmental conditions. Full article

Leaf colour is a valuable morphological phenotype for studying plant metabolism and physiology. To elucidate the mutation mechanism of leaf colour variation in maize, we compared the ethyl methylsulfonate (EMS)-induced maize mutant zmpgl, which has light green leaves, with the wild-type maize line B73. At the seedling stage, the zmpgl mutant presented distinct light green leaf colouration. Comprehensive analyses revealed that both the photosynthetic parameters and pigment contents of the mutant seedlings were significantly lower than those of the wild-type seedlings. Transmission electron microscopy of the mutant leaves revealed alterations in the chloroplast structure, which consequently impaired the photosynthetic efficiency and accumulation of organic matter. Through integrated transcriptomic and metabolomic profiling, we identified differentially expressed genes (DEGs) and differentially abundant metabolites associated with the zmpgl phenotype. These molecular components were associated with pathways related to plant metabolism, chloroplast structure-associated hormone signalling, and redox homeostasis. Further investigation revealed a significant differential expression of genes involved in several critical biological processes, including tetrapyrrole synthesis, lipid metabolism (related to leaf photosynthesis), amino acid metabolism (associated with chlorophyll synthesis and the light response), and abscisic acid (ABA) biosynthesis. These processes are crucial for plant photosynthesis, respiration, and catalytic functions. This study not only provides a valuable resource for further investigation of plant photosynthetic systems but also establishes a foundational framework for the comprehensive functional characterisation of genes involved in the leaf colour change in the zmpgl mutant. These findings contribute to our understanding of the molecular basis of leaf colour variation and its impact on photosynthetic performance in maize. Full article

Research on fish skin artefacts’ dyeing practices among the Nivkh, Nanai, Ulchi, Udegei, Oroch, and Negidal Indigenous Peoples of the Amur River basin remains scarce. These fishing communities traditionally crafted fish skin garments, essential to their subsistence and spiritual life, adorning them with protective motifs. While artistic and cultural aspects of these belongings have been explored, their dyeing techniques remain understudied. This multidisciplinary research examines natural colourants in fish skin artefacts from international museum collections, using historical textual research, ethnographic records, Native Traditional Knowledge, and previous dye analysis by museum conservators. Findings reveal a restricted but meaningful palette of red, blue, yellow, and black colourants, sourced from plants, minerals, and organic materials. Early dyers extracted blue from indigotin-rich plants such as Polygonum tinctorium, or from Commelina communis petals. Red hues were obtained from Carthamus tinctorius petals, introduced through Silk Route trade networks, or from minerals like red ochre. Black was derived from carbon black, while riverine minerals were ground with dry fish roe diluted with water to create additional colour variations. This study first reviews fish skin use in Amur River Indigenous cultures, explores nineteenth-century dyeing materials and techniques, and finally considers broader implications for Indigenous material heritage. Full article

Axinite crystals from the type locality (Oisans, French Alps) are considered among the more remarkable specimens known for their quality (lustre, colour, size, and purity) and crystalline forms. However, they have been the subject of only a few in-depth studies. This lack of knowledge provided the opportunity for a systematic survey of axinites from Saint-Christophe-en-Oisans, where crystals appear to cover an extensive range of Fe-Mn substitution from an Fe-rich (axinite-Fe) to a Mn-rich field (axinite-Mn) in a same crystal, with compositional variations much more significant than initially described. An in-depth characterisation of the chemical zonation of the crystals using EPMA, Raman spectroscopy, X-ray micro-fluorescence, and LA-ICP-MS was carried out on the crystals showing the most significant variability. The micro-XRF method appeared extremely useful for describing spatial variations in chemical composition at the centimetre scale and preparing other in situ methods. Fe(Mg)-Mn substitution covers a large range but the Mn-enriched growth zones are relatively thin and localised at the periphery of crystals. In addition, chemical zonations highlighted in this study also reveal contrasted incorporation of trace elements as a function of the Fe/Mn ratio (in particular, Be, HREE, Sc, Ga, In, and Co), indicating changes in fluid chemistry during the crystal growth. Full article

Cold plasma (CP) is a non-thermal technology, successfully used to decontaminate and extend the shelf-life of various foods. However, CP can cause quality deterioration in sensitive matrices, such as fish products. This research aimed to evaluate the effect of CP treatment obtained using different gas mixtures (80% Ar/20% O₂, or 80% N₂/20% O₂) with a surface dielectric barrier discharge (SDBD) on the decontamination of spoilage microflora, the main quality indices and the sensory acceptability of seabream (Spaurus aurata L.) fillets during refrigerated storage. At the beginning and at the end of the shelf life, lipid and protein oxidation indices and the fatty acid profile were evaluated. Results showed that, despite a low initial microbial decontamination (0.2–0.3 Log CFU/g), an inhibition of the growth of the main spoilage bacteria was observed resulting in an increase of the microbiological shelf life of around 40% for both treatments. Although a slight increase in lipid and protein oxidation was observed (up to around 5 mg MDA/kg and 4 nmol/mg of protein for TBARs and carbonyl content respectively), the sensory acceptability was higher for plasma treated samples, while the fatty acid profile was not affected and only a slight variation in the surface colour was observed (L* value increase by 3 points), confirming that CP could represent an interesting strategy to extend the shelf life of seafood products with minimal impact on quality and nutritional value. Full article

The research presented in this article seeks to identify the possible causes of reinforcement shadows (RS) on the surface of concrete test specimen produced under laboratory conditions. Different hypotheses about RS were selected based on factory practices and simulated in the study. The test specimens were cast horizontally in contact with steel form-facing surfaces coated with a water-soluble release agent. In addition, two scenarios were analysed during specimen production: reinforcing mesh was fixed using plastic spacers or tie wire. The analysis of the reinforcement shadows was based on visual inspection, taking photos, surface moisture content measurements, and colour variation analysis using the Natural Colour System. It was concluded that RS, which are typically characterized by darker lines, can be defined by the percentage of black colour present in the shadowed area compared to the percentage of black colour in the surrounding area. This percentage can be quickly assessed on a factory scale using digital colour readers that provide timely information. The reduced concrete cover thickness from 35 mm to 10 mm revealed light horizontal dark lines on the exposed surface. It was hypothesised that the gap of less than 10 mm between the reinforcing bars and the steel form-facing plate, along with the sieving effect of the fresh concrete, can retard the cement paste hydration process, resulting in unhydrated ferrite phases that contribute to the dark colour of the unhydrated cement. The release agent sprayed on the steel form-facing surface straight through the reinforcing mesh created a RS effect of the reinforcement on the exposed concrete surface. The absence of a release agent under steel rebars decreased the wettability at the interface between the formwork and fresh concrete, resulting in dark lines during the curing process. It is important to avoid such cases when manufacturing precast reinforced concrete elements. Quantitatively assessing RS and proposing a standardized method for calculation and categorization could be a new research direction in the future. Full article

Coral reefs are vital ecosystems facing rapid degradation. This research explores architectural design solutions for bio-enhancing modular prototypes to support coral attachment and growth. Inspired by coral polyps, nine biomimetic designs were created using Maya and Rhinoceros 3D to optimise surfaces for coral settlement. A total of 75 prototypes (15 × 15 cm) were fabricated, incorporating four materials—PETG, concrete, oyster concrete, and clay—and seven colour variations—sand, translucent green, translucent brown, red, pink, grey, and reddish. The findings indicate that 3D printing with PETG was the most efficient fabrication method but required structural support and long-term underwater testing, while oyster concrete demonstrated potential for self-sustaining structures. This study highlights the role of architectural design in marine restoration, promoting biodiversity and resource-efficient solutions. By integrating corals into the design, these structures can self-grow and adapt, reducing material consumption and long-term maintenance. Full article

Secondary sexual traits, such as specific body parts or colouration, play an important role in mating interactions. It has been proposed that they function as quality indicators driven by sexual selection. In birds, much attention has been paid to the study of feather pigmentation, especially in diurnal passerines. However, recent research demonstrates that structural achromatic colours are likely to be of similar importance for communication, especially for species inhabiting poorly lit environments and that are active at night. Using 15 years of capture–recapture data from a long-term study on adult European Nightjars (Caprimulgus europaeus), we investigated the role of males’ white tail and wing markings as secondary sexual traits. We show that the inter-individual variation in marking size exceeds that of the other morphometric variables, suggesting that wing and tail markings could be subject to sexual selection. Older males, individuals with a higher body condition index, and long-term territory holders had larger markings, while these effects were particularly pronounced in terminal tail feather markings. The importance of markings for signalling is likely related to their observed use in social displays. Pronounced site differences in tail marking sizes and annual variation suggest environmental factors acting on the ornaments that remain to be further examined. Full article