Color Appearance Research Articles

Individual color matching functions from cross‐media color‐matching experiment

AbstractHuman color vision exhibits substantial variability, challenging the accurate measurement and reproduction of individual color appearances. This paper introduces a novel cross‐media color‐matching experiment that combines physical pigments and digital displays, providing a practical and efficient solution to measure individual color matching functions (CMFs). By using the Kubelka–Munk theory to synthesize broadband spectral pigments, optimized metameric pairs can be created to significantly differentiate categorical observers. Psychophysical experiment results reveal the superiority of specific CMFs for individual observers, surpassing standard models like the CIE 1931 2‐degree CMFs. This study also underscores the significance of employing CMFs for personalized color reproduction and explores the potential benefits of using higher bit‐depth displays, narrower‐band displays, and increasing repetition counts to enhance the accuracy of the color matching process.

Quercetin-enriched animal-free scaffolds for promoted cell proliferation and differentiation in cultured meat production

To solve the challenges posed by increasing meat consumption, it is imperative to develop polysaccharide composite edible scaffolds for cell-cultured meat production using novel food production technologies. This study developed some non-animal-origin polysaccharide composite scaffolds for cell-cultured meat production, based on chitin‑sodium alginate and crosslinked with quercetin. The results indicated that the chitin‑sodium alginate-quercetin (CH-SA-QR) scaffolds exhibited a porous and loose structure, and excellent mechanical support capability and cell adhesion sites. Meanwhile, QR1 and QR1.5 scaffolds were screened by immunofluorescence staining, RT-qPCR, and SEM imaging results to facilitate the proliferation and differentiation of cells and enhance the generation of myotube fusion and extracellular matrix protein. Importantly, the texture of the fried cultured meat was similar to traditional beef or even more tender, while the color appearance of the cultured meat was different from beef, but more similar to fried meat cutlets. These results suggest that cultured meat produced based on CH-SA-QR scaffolds could provide consumers with more choices.

Developing Canva-Based Sitekol on Collage Topic for First-Grade Public Elementary School Students

The study aims to create a learning media product using Canva for elementary school students to alleviate the lack of learning materials, which has been negatively impacting student academic performance. The research also seeks to evaluate the practicality and effectiveness of the learning media product. This study uses research and development with ADDIE design. The results of the analysis revealed that some students do not meet the minimum standards and require learning tools to improve their skills in cutting and sticking when studying collage topics. This research developed Sitekol media on collage topics in the design stage using Canva and Wordwall applications. The validity test results showed that Sitekol media received a 90% score from media experts for color appearance, image combinations, fonts, media layout, videos, and practical use. Material experts rated it at 95.3% for material aspects, levels of thinking, and supporting learning content. Students also found Canva-based Sitekol learning media to be beneficial as a teaching tool due to its accessibility, portability, convenience, interactive features, and detailed learning media instructions. The statistical tests conducted resulted in significant findings with high average values. Students responded very positively to the practicality of the media, giving an average score of 4.9 out of 5, indicating 98% of the ideal score. It can be concluded that using Canva-based Sitecol learning on grade 1 collage material exhibits practicality and validity as a learning medium.

Physicochemical quality retention of ‘Sucrier’ bananas (Musa acuminata AA group cv. ‘Kluai Khai’) by jicama starch-based postharvest treatment

The objective of this research was to develop a new type of edible coating using jicama starch (JS) in order to control the postharvest deterioration of ‘Sucrier’ bananas (Musa acuminata AA group cv. ‘Kluai Khai’) during the ripening process in ambient condition (25 ± 1 °C, 85-90 % RH). The preliminary experiment was carried out to investigate the impact of JS concentration (0, 2.5, 5.0, and 7.5 % w/v) on the postharvest quality of bananas. The application of JS demonstrated a delay in banana ripening, including color development, weight loss, and fruit firmness. Within the JS-treated banana groups, 5.0 % treated bananas displayed higher firmness compared to the other groups. Therefore, a validation experiment was conducted to verify the subsequent physicochemical alterations in bananas after subjecting bananas to 5.0 % JS coating in comparison to non-treated bananas during storage at ambient condition. The JS treatment maintained the color and visual appearance by minimizing the formation of malondialdehyde content and electrical conductivity during storage. Furthermore, it resulted in a delay in the increases in total soluble solid, titratable acidity, BrimA, and total carotenoid concentrations in the pulp. Nevertheless, the ascorbic acid and phenolic contents and 2,2-diphenyl-2-picrylhydrazyl scavenging activity of the control samples were likely to be higher than those of the treated bananas, whereas the ferric reducing antioxidant potential of both control and treated bananas showed a comparable trend throughout storage. The outcomes demonstrate that the utilization of JS is an effective approach for improving the overall storage capacity of ‘Sucrier’ bananas.

Dataset-level color augmentation and multi-scale exploration methods for polyp segmentation

Automatic segmentation of polyps from colonoscopy images plays a critical role in early screening and treatment of colorectal cancer. Although deep learning methods have made significant progress, precise polyp segmentation faces two challenges: (1) the imbalance of color appearances in the limited training dataset hinders the generalization of the model, and (2) polyps have the diverse scales, locations and shapes with blurred boundary. To address the issues, Dataset-Level Color Augmentation (DLCA) and Convolutional Multi-scale Attention Module (CMAM) are proposed. DLCA employs the dataset-level color knowledge and generate new color appearances, to avoid the model learning false associations with colors. Meanwhile, CMAM simultaneously explores the region and boundary clues and model multi-scale context, which improves the accuracy of polyp localization and fine-grained segmentation. We conduct comprehensive experiments and compare our network with state-of-the-art methods. The proposed model is superior on multiple polyp datasets, especially on ETIS, where mDice and mIoU reach 0.839 and 0.766. Furthermore, it is validated that DLCA can be widely applied to most polyp segmentation methods, and CMAM is practical and plug-and-play. Finally, the model demonstrates promising generalization to breast ultrasound and skin lesion segmentation.

Seeing through another’s eyes: Modeling and correcting for individual differences in color appearance

Seeing through another’s eyes: Modeling and correcting for individual differences in color appearance

Color Design for Daytime Radiative Cooling: Fundamentals and Approaches

The escalating global energy crisis and the worsening global warming have intensified the heat threats posed by high temperatures. Traditional cooling methods like air conditioning are not only energy-intensive but also contribute to environmental degradation. In response, there is a pressing demand for novel, eco-friendly cooling technologies, particularly amid the growing global push for carbon neutrality. As a passive cooling method that does not require any extra power input, radiative cooling offers a promising solution, utilizing thermal radiation to cool the Earth by transferring heat directly to outer space. However, current radiative cooling materials generally have a monotonous white appearance due to their high reflectivity to solar radiation, which, considering their prospects for outdoor applications, has prompted the need for color design. Recent advancements have led to the development of colored passive radiative cooling (CPRC) materials, offering passive cooling without additional energy input, colorful aesthetic appearance, and facile preparation methods. In this review, the latest progress in CPRC materials are summarized, covering fundamental principles, various color design solutions, and potential applications. Besides, the coloration strategy including chemical, structural, and luminescent approaches for CPRC are comprehensively analyzed, providing insights into the future development and deployment of CPRC materials for outdoor energy efficient systems and thermal regulation.

Electrospun nanofiber composites as a novel preservation coating with antimicrobial and antifungal functions for the archaeological linen textiles

In an attempt to prevent the biodeterioration of ancient textiles, we utilized electrospun composite nanofibers (NFs) for the first time as a coating layer to enhance their antimicrobial and antifungal properties. In this study, we applied a few layers of electrospun NFs derived from various polymers loaded with silver nanoparticles (n-Ag) and 4-chloro-m-cresol onto the surface of aged linen fabric mockups, simulating ancient textiles. The results showed that the coating layer had no discernible effect on the tested samples’ morphology, colour, and optical appearance. Additionally, the investigated samples exhibited significant antibacterial efficacy against Escherichia coli and Staphylococcus aureus. Furthermore, the examined samples displayed significant inhibition of growth in cultures of Aspergillus species isolated from ancient linen fragments preserved in the Cairo Egyptian Museum. These results suggest that electrospun NFs offer a promising strategy for conserving archaeological textiles against biodeterioration and may open a new avenue for using electrospun NFs in the conservation of other archaeological materials.

StyleRF-VolVis: Style Transfer of Neural Radiance Fields for Expressive Volume Visualization.

In volume visualization, visualization synthesis has attracted much attention due to its ability to generate novel visualizations without following the conventional rendering pipeline. However, existing solutions based on generative adversarial networks often require many training images and take significant training time. Still, issues such as low quality, consistency, and flexibility persist. This paper introduces StyleRF-VolVis, an innovative style transfer framework for expressive volume visualization (VolVis) via neural radiance field (NeRF). The expressiveness of StyleRF-VolVis is upheld by its ability to accurately separate the underlying scene geometry (i.e., content) and color appearance (i.e., style), conveniently modify color, opacity, and lighting of the original rendering while maintaining visual content consistency across the views, and effectively transfer arbitrary styles from reference images to the reconstructed 3D scene. To achieve these, we design a base NeRF model for scene geometry extraction, a palette color network to classify regions of the radiance field for photorealistic editing, and an unrestricted color network to lift the color palette constraint via knowledge distillation for non-photorealistic editing. We demonstrate the superior quality, consistency, and flexibility of StyleRF-VolVis by experimenting with various volume rendering scenes and reference images and comparing StyleRF-VolVis against other image-based (AdaIN), video-based (ReReVST), and NeRF-based (ARF and SNeRF) style rendering solutions.

The effect of weighting on the color appearance of dyed silk fabric

The weighting process may change the color appearance of silk. The objective of the present study is to evaluate the effect of weighting with methyl methacrylate (MMA) on the color appearance of silk fabric using the response surface method. For this purpose, a CCD design was used to investigate the effect of methyl methacrylate monomer concentration and dye concentration on color appearance and percentage of weight gain of silk fabric. Analysis of variance, response surface, and contour plots of the colorimetric characteristics of the weighted silk fabric show that the methyl methacrylate concentration has a significant effect on color parameters such as L*, a*, b*, C*, and hue angle of the weighted silk fabric. The results indicate that the weighting process changes the color of silk fabric.

Sex identification of sun conure (Aratinga solstitialis) using loop-mediated isothermal amplification of W and Z spindlin chromosomes

Background and Aim: The sun conure (Aratinga solstitialis), a bird belonging to the Psittaciformes family, is a popular pet because of its bright color and beautiful appearance. The sun conure is a monomorphic bird with similar appearances between males and females, making sex identification difficult by observing the external morphology. Therefore, molecular techniques are utilized. Loop-mediated isothermal amplification (LAMP) is a molecular technique that is often applied for sex identification in birds and is a quick and simple method that can be used in the field. This study used the LAMP technique to improve sex identification in sun conures by observing the color change of hydroxy naphthol blue. Materials and Methods: Two primer sets, SunSpin-W and SunSpin-Z, were designed for sex identification in sun conures using the LAMP technique specific to the spindlin gene. The developed LAMP reaction was tested for optimal conditions, sensitivity, and specificity compared with the polymerase chain reaction (PCR) technique. Results: The SunSpin-W primer set amplified only female birds, whereas the SunSpin-Z primer set amplified DNA from both male and female birds. The primer sets were optimized at 62°C for 45 min. A positive result was visible to the naked eye from the color change of the reaction. In the LAMP assay, the lowest detectable concentration was 10 pg/μL and in the PCR assay, it was 1 ng/μL, while a 100% accuracy rate in sex identification was observed when comparing the LAMP assay results with the PCR assay. Conclusion: This study successfully developed a LAMP technique for sex identification of sun conure, which took 45 min to complete and can be expanded for use in the field. Keywords: loop-mediated isothermal amplification, sex identification, spindlin gene, sun conure.

Advanced Dehydration Techniques Standardized for Flowers of Gomphrena globosa L.

The present experiment was conducted on standardizing dehydration technique for Gomphrena globose flower by using embedding drying methods in room temperature and hot air oven at 55°C was done. The experiment consisted of 10 treatments with 3 replications designed in completely randomized design. Treatments used were as; T1-Boric acid (room temperature), T2-Silica gel (room temperature), T3-Sand (room temperature), T4-Sawdust (room temperature), T5-Cocopeat (room temperature), T6-Boric acid (hot air oven at 55 °C), T7-Silica gel (hot air oven at 55 °C), T8-Sand (hot air oven at 55 °C), T9-Sawdust (hot air oven at 55 °C), T10-Cocopeat (hot air oven at 55 °C). The most reduction in flower fresh and dry weight, measuring 2.36 and 2.12 g, was observed in Treatment T7 (Silica gel with hot air oven at 55°C), where silica gel was employed as the desiccant. The least reduction in flower fresh and dry diameter, measuring 1.92 and 1.81 g, was observed in Treatment T7 (Silica gel with hot air oven at 55°C), where silica gel was employed as the desiccant. The highest drying duration for gomphrena in T3 (Sand) and T4 (Sawdust) treatments was 234.21 and 210.40 hrs at room temperature. The boric acid and silica gel demonstrated outstanding performance in terms of quality parameters, including texture, color, and overall appearance. Among all treatment, embedding drying with silica with hot air oven dehydration at 55°C was found to be best in term of reduction in weight, diameter and overall colour, appearance and texture of Gomphrena globose flowers.

Non-destructive identification of iron oxide crystals in 15th century A.D. Chinese imperial red overglaze decoration

Red overglaze decoration is one of the earliest and most important colorful overglaze decorations in China, which had a remarkable influence on the successful firing and development of polychrome overglaze porcelains. The uncontrollability of red overglaze decoration led to a certain proportion of defective porcelain products in the Ming Dynasty (1368–1644 CE). To investigate and identify the coloring effect of iron oxide crystals in red overglaze decoration, three groups of samples with different color appearance were non-destructively analyzed and observed by OM, spectrophotometer, XRF, Raman spectroscopy, XRD and SEM. The results show that the hue of red overglaze decoration was caused by the different crystal forms of iron oxide. Hematite (α-Fe2O3) displays red color, while maghemite (γ-Fe2O3) and magnetite (Fe3O4) yield orange-red and dark red colors. With the similar raw materials and manufacturing processes, the presence of maghemite and magnetite are relatedto subtle differences in processing raw materials and firing them.

A time and temperature dependent biosynthesis of silver nanoparticles using the extract of Platycladus orientalis’ fruit

Silver nanoparticles (AgNPs) have gained notable/ huge attention, particularly in the biomedical and antibacterial fields, owing to their distinctive characteristics. Biological synthesis of AgNPs is a prominent method due to its ease of preparation, eco-friendliness, non-toxicity and time efficiency. Herein, AgNPs were synthesized using an extract from "Platycladus orientalis" and their antimicrobial and biological properties were thoroughly investigated. The scaling down of Ag⁺ to Ag⁰ was evident through the appearance of a yellow brownish colour. AgNPs were characterized by UV–Visible spectrum, X-ray diffraction (XRD), and scanning electron microscopy (SEM). UV–Visible spectroscopy revealed absorption peaks at around 440 nm for AgNPs synthesized from fruits’ seat coat of Platycladus orientalis. TEM analysis indicates the average size of AgNPs is approximately 50 nm. Powder XRD confirmed the crystalline nature of the AgNPs, with prominent peaks corresponding to face-centred cubic structures. FTIR analysis identified key functional groups involved in the synthesis process. SEM images displayed agglomerated AgNPs with varying diameters and particle dispersion. Molecular docking results showed favourable binding interactions of AgNPs with the protein 2BTD, with a docking score of -3342 kcal/mol, indicating potential biological activity. These findings highlight the effective synthesis of AgNPs using Platycladus orientalis and their significant potential for biomedical applications.

Shelf-life Prediction of Canned Pacri Nanas Using the Accelerated Shelf-life Test (ASLT) Method

Pacri nanas is a traditional Malay food made from fresh pineapple cooked with various herbs/spices and coconut milk. Pacri nanas can be marketed more widely if packed in cans. This study aims to estimate the shelf-life of canned pacri nanas using the Accelerated Shelf-Life Test (ASLT) method. The storage temperatures used in this study were 35 °C, 45 °C, and 55 °C. The parameters observed were sensory characteristics: color, aroma, taste, texture, and overall appearance. The results showed that all parameters decreased during storage, as indicated by the negative slope graph. The first-order reaction affects the sensory parameters decrease during storage. The lowest activation energy (Ea) value used to determine the product shelf-life is the aroma parameter with the regression equation y = -2416.4x + 5.9911, so the resulting activation energy is 4798.97 cal/mol. The shelf-life of pacri nanas at storage temperatures of 35 °C, 45 °C, and 55 °C were 11.3, 8.8, and 7.0 months, respectively. Storage of canned pacri nanas is recommended at room temperature (30 °C) with an estimated shelf-life of 12.8 months.

A Tunable Threshold Colorimetric DNA Logic Gate for Intuitive Assessment of Chemical Contaminant Exceedance.

Current molecular logic gates are predominantly focused on the qualitative assessment of target presence, which has certain limitations in scenarios requiring quantitative assessment, such as chemical contaminant monitoring. To bridge this gap, we have developed a novel DNA logic gate featuring a tunable threshold, specifically tailored to the limits of contaminants. At the core of this logic gate is a DNA-gold nanoparticle (AuNP) hybrid film that incorporates aptamer sequences to selectively bind to acetamiprid (ACE) and atrazine (ATR). Upon interaction with these contaminants, the film degrades, releasing AuNPs that, in the presence of Hg2+, catalyze the oxidation of TMB, resulting in a visible blue coloration on test paper. This aptamer-enabled process effectively establishes an OR logic gate, with ACE and ATR as inputs and the appearance of blue color as the output. A key innovation of our system is its tunable input threshold. By adjusting the concentration of Hg2+, we can fine-tune the color mutation points to match the input threshold to predefined limits, such as Maximum Residue Limits (MRLs). This alignment allows semiquantitative assessment of contaminant levels, providing intuitive visual feedback of contaminant exceedance. Validation experiments with spiked samples confirm its accuracy and reliability by closely matching HPLC results. Therefore, our colorimetric DNA logic gate is emerging as a promising tool for easy and semiquantitative monitoring of chemical contaminants across diverse applications.

Generic color correction for tone mapping operators in high dynamic range imaging

One of the significant challenges in tone mapping is to preserve the perceptual quality of the tone-mapped images. Traditional tone mapping operators (TMOs) compress the luminance of high dynamic range (HDR) images with little to no consideration of image color information resulting into suboptimal colors. Existing color management algorithms require either manual parameter tuning or introducing lightness and hue shifts. The current study aimed to develop a color correction model in plausible agreement with the psychophysical phenomenon of color appearance perception for optimal color reproduction of tone mapped images. The proposed model leverages CIECAM16 perceptual correlates i.e., lightness, chroma, and hue. It is adaptive and entirely automatic while preserving the lightness of the tone-mapped image and maintaining the hue from the HDR image. Moreover, it does not require any gamut mapping correction algorithm in natural color reproduction. The effectiveness of the model was validated using objective and subjective methods. The experiments revealed that the model achieved optimal color reproduction in terms of the naturalness of the colors.

Distribution of active ingredients and quality control of Forsythia suspensa with AP-MALDI mass spectrometry imaging.

The fruits of Forsythia suspensa (F. suspensa) have been used as a traditional Chinese medicine for 2000 years. Currently, the quality control of F. suspensa strictly follows the instructions of Chinese Pharmacopeia, which mainly controls the content of forsythoside A, phillyrin, and volatile oil. In this study, air pressure MALDI mass spectrometry imaging (AP-MALDI MSI) was used to evaluate the quality of F. suspensa fruits and the distribution of dozens of active ingredients. The variation of active ingredients was measured for more than 30 batches of samples, regarding harvest time, cultivated environment, shelf-life, and habitat. Fifty-three active ingredients could be detected in F. suspensa fruits with AP-MALDI MSI. Seven active ingredients were upregulated, four ingredients downregulated, and 15 ingredients did not change in ripe fruits. A sharp variation of active ingredients in late September was observed for the Caochuan fruits harvested in 2019, which is closely related to the appearance of the ginger color of the pericarp under the microscope observation. The microscope observation is a reliable way to classify ripe and green fruits instead of outlook. Just considering forsythoside A and phillyrin, it is found that wild fruits are better than cultivated fruits, but cultivated fruits have high contents of other ingredients. The shelf-life of F. suspensa fruits is proposed to be 3 years, considering the 26 ingredients investigated. It was found that Luoning wild fruits are better than those from Caochuan with a new evaluation method. Mass spectrometry imaging is an easy, objective, and effective method to evaluate the quality of F. suspensa fruits.

Colour difference detection algorithm for warp‐knitted fabric based on image colour appearance model

AbstractDetecting colour differences in warp‐knitting fabric is essential to ensure its quality. Machine vision algorithms are commonly used for automatic colour difference detection. However, the current algorithm directly extracts RGB (red, green, blue) colour stimulus values from the image without considering the image's colour attributes, leading to a significant error in colour difference detection. To solve this issue, a colour appearance model is introduced into the field of colour difference detection for warp‐knitted fabric. Initially, a colour appearance model based on CAM16 is established, and the critical parameters are calculated to obtain the colour appearance attribute of the fabric. The colour difference calculation formula is then constructed in the uniform colour space of CAM16‐UCS. A template selection algorithm based on principal component analysis was designed to select warp‐knitted cloth images with standard colours. Subsequently, a cloth colour difference detection algorithm was developed using the cloth colour profile model. The performance of the colour difference formula based on the colour profile model was evaluated using the PF/3 method. To compare the CIELab, CMC(2:1), and CIEDE2000 colour difference formulas, standardised residual sum of squares was used. The results indicated that the colour difference formula based on the colour‐appearance model is about 5.32% different from the visual colour difference perceived by the human eye. However, it can perform as well as the CMC(2:1) colour difference formula, which is widely used in the textile industry.

Cultivation of Limnospira maxima under extreme environmental conditions in Saudi Arabia: Salinity adaptation and scaling-up from laboratory culture to large-scale production

Limnospira maxima has been adapted to grow in high salinity and in an economically alternative medium using industrial-grade fertilizers under harsh environmental conditions in Saudi Arabia. A sequence of scaling-up processes, from the laboratory to large-scale open raceways, was conducted along with gradual adaptation to environmental stress (salinity, light, temperature, pH). High biomass concentration at harvest point and areal productivity were achieved during the harsh summer season (1.122 g L−1 and 60.35 g m−2 day−1, respectively). The average protein content was found to be above 40 % of dry weight. Changes in the color and morphological appearance of the L. maxima culture were observed after direct exposure to sunlight in the outdoor raceways. These results demonstrate a successful and robust adaptation method for algal cultivation at outdoor large-scale in harsh environment (desert conditions) and also prove the feasibility of using hypersaline seawater (42 g kg−1) as an algal growth medium.