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Abstract: Introduction. There is an accumulating evidence of various ophthalmological symptoms, accompanied by visual impairment, post-COVID-19. We hypothesized that color vision may have been affected post-COVID-19 too manifesting as changes in color-naming patterns. To test this hypothesis, we compared color naming in individuals who have recovered from COVID-19 (N = 201, 54 men and 147 women, aged 19–65 years, M = 33.4, SD = 13.2) and those participants whose responses were obtained before the pandemic (hereafter, non-COVID-19 controls) (N = 2,457, 1,052 men and 1,402 women, aged 16–98 years, M = 41.36, SD = 17.7). Methods. We collected data in an online experiment (http://colournaming.com) with Russian respondents in their native language. Participants were presented, with virtual color cards selected from 606 stimuli randomly by a computer program. We asked respondents to name each color using the most appropriate color descriptor (an unconstrained color-naming method). Results. The study showed that, compared to non-COVID-19 controls, post-COVID-19 respondents revealed an altered pattern of color naming. In particular, we found a significant increase in ‘brown’, ‘green’, and ‘gray’ names, along with an increased use frequency of achromatic modifiers “dirty”, “pale”, “dull”, and “pastel”. Discussion. These differences suggest general “darkening” and decreased saturation of perceived colors. The change in the color-naming pattern provides an indirect evidence of the impact of coronavirus on color vision. We speculate that a relatively high frequency of use of color terms koričnevyj ‘brown’ and seryj ‘gray’ may reflect an accelerated aging of the crystalline lens, while general “darkening” and desaturation of perceived colors may point to an affected processing of luminance contrast. These assumptions are currently being tested (by the authors) in COVID-19 survivors by using a color vision diagnostic test.

Thermal treatments can be considered as an accelerated ageing, bringing partly similar changes in properties as naturally aged wood. Thermal treatment was applied on white mulberry (Morus alba L.), a dominant species for making musical instruments from middle-East to Far-East, to investigate the effects on the vibro-mechanical and physical properties of this wood, and the results compared to previously published data on spruce (Picea abies Karst.) as a reference for the soundboard of Western string instruments. Thermal treatment (TT) at 150 °C and 0% of relative humidity was applied to five analogous groups of specimens with five different durations (2.5, 8, 24, 72, 261 hours). Humidity re-conditioning of specimens was done to explore the reversibility of TT effects. Physical and vibrational properties such as specific gravity (γ), equilibrium moisture content (EMC), CIELab colorimetric values, specific modulus of elasticity (E’/γ) and damping coefficient (tanδ) in longitudinal (L) and radial (R) directions, have been measured after stabilisation of samples in standard conditions (20 °C, 65% RH), before and after TT and then after re-conditioning. Untreated mulberry had a low EMC, very low L/R anisotropy and low E’L/γ, and relatively low tanδ. Weight loss (WL) and CIELab values evolved similarly during TT for mulberry and for previous results on spruce, however, their EMC and vibrational properties were affected differently. This could be explained in part by the low anisotropy of mulberry, and in part by its particular extractives. The parts of irreversible effects, linked to chemical modification or degradation, and of reversible effects, linked to physical configuration, were different between mulberry and spruce. The applied treatments did not bring permanent “improvements” in vibrational properties of mulberry, yet its colour appearance was enhanced.

Teakwood from fast-growth plantations is commercialized at increasingly younger ages for economic reasons. However, wood features are influenced by the age of the tree. This study examined how age affects heartwood proportion, color parameters, chemical composition, and natural teakwood durability. Trees with 5, 10, 15, and 20 years of fastgrowth at commercial plantations located in Mato Grosso, Brazil were evaluated. The base diameter of the trees ranged from 13.1 (5 years) to 28.3 cm (20 years), and the heartwood percentage increased from 16.3 to 60.0%, respectively. The color parameters in the CIELab system indicated that wood became darker and more saturated, and the predominance of yellow color decreased compared with red as age advanced. The total extractive content ranged between 7.4 (5 years) and 9.6% (15 years), without a clear trend of age affecting the extractive content. The extractives from five-year-old wood were mainly composed of tectoquinone (43.3%), phthalic acid (19.1%), and 1,3-indandione (9.2%), while those from 20-year-old wood were mainly composed of tectoquinone (60.7%), lapachol (13.8%), and phthalic acid (9.7%). Teakwood can be classified as resistant (5 years) to very resistant (20 years) after being submitted to an accelerated decay test. [ABSTRACT FROM AUTHOR]

Flower color not only determines the quality and commercial value of ornamental plants, but it also plays a vital role in ecological processes such as pollinator attraction. This study aimed to investigate the relationship between flower color and the cellular physicochemical factors of Bletilla striata. The color space values of 21 samples were initially determined, followed by a selection of five samples with significant color differences for testing cell shape, total flavonoid content (ranging from 1.86 to 5.42 mg/g), total anthocyanin content (ranging from 0.52 to 292.62 (A530 − 0.25 ∗ A657)/g), cell pH (varying between 5.03 and 5.74), and metal ion content (including Al3+, Ca2+, Fe3+, K+, Mg2+, Na+, P5+, Zn2+, Mo6+, Cu2+, and Mn2+). The flowers of Bletilla were predominantly purple, pink, and yellow; and distributed in quadrants I, II, and IV on the a* and b* rectangular coordinate. The a* value was identified as the primary color indicator for this species. Total anthocyanin content and Zn2+ showed a significant positive correlation with a*, while Al3+, Ca2+, Fe3+, Mg2+, Na+, and Mn2+ demonstrated negative correlations. Cell shape, flavonoid content, and pH had nonsignificant correlations with a*. In conclusion, the total anthocyanin content and metal ions play crucial roles in determining the flower color of B. striata, which can have implications for pollinator attraction. Future research should focus on understanding the complex interactions between these factors to develop novel ornamental plant varieties with desirable flower colors and enhanced ecological functions. [ABSTRACT FROM AUTHOR]

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Summary: Pinot noir wines were made with inclusion of different amount of whole bunches or grape stems: destemmed grapes only (DS), 30% whole bunch (WB30), 60% whole bunch (WB60), 100% whole bunch (WB100), and destemmed grapes with 100% stems added back (DS100). Wines were analysed using modified Somers assay and CIELab method at the end of fermentation and after a 2 years bottle ageing. CIELab analysis showed that DS100 was significantly different from all other treatments at both sampling points, and whole bunch addition treatments (except of WB30) only showed significant colour difference compared to DS treatment after bottle ageing. Total anthocyanins were significantly reduced in stem inclusion treatments at the end of alcoholic fermentation, but after the 2 years bottle ageing, only DS100 treatment showed significantly lower anthocyanins than DS treatment. Stem inclusion treatments significantly increased tannin concentration. Total anthocyanins and tannins in wines reduced by 69%–71% and 24%–31% respectively after bottle ageing. [ABSTRACT FROM AUTHOR]

The sensory properties of fruit and vegetables are a result of taste and aroma caused by many volatile and nonvolatile compounds. The sum of organic acids (malic and citric acids) and soluble sugars (fructose and glucose), as well as their balanced combination and interaction, contributes to the characterization of the tomato flavour. The ratio of sugars and organic acids is the key to the sweetness and sourness of tomatoes. This study aimed to determine the sugar and organic acid content, as well as several physicochemical parameters, of eight tomato landraces from Croatia. All the parameters investigated differed between the tomato landraces. The PLS-DA analysis showed that the most important parameters in tomato landrace discriminatory character are malic acid, fructooligosaccharide content, citric acid, dry matter. The results obtained show a significant positive correlation between tomato dry matter and sugar content. At the same time, fructose and sucrose content is negatively correlated with the green to red hue of tomato peel, as well as positively with the blue to yellow hue, indicating that the sugar content increases with yellow color intensity. The blue to yellow hue of the peel color also positively correlates with citric acid content. [ABSTRACT FROM AUTHOR]

A visual and easy-to-implement representation approach of red wine color is proposed in this work. The wine color under standard conditions, called feature color, was reproduced in the form of a circular spot. The feature color was further decomposed into two orthogonal aspects, the chromatic and light–dark components, characterized in the form of chromaticity distribution plane and lightness distribution plane, respectively. The color characterization of wine samples showed that this method well represented the color characteristics and can provide intuitive visual perception of wine color, in a way that is more reliable and convenient than the photographic method. The applications for monitoring the color evolution during winery and laboratory fermentation and the age discrimination of 175 commercial red wines suggest that this visual method is effective for color management and control of wine during fermentation and aging. The proposed method is a convenient way to present, store, convey, understand, analyze and compare the color information of wines. [ABSTRACT FROM AUTHOR]

Generations of sensors have been developed for predicting food sensory profiles to circumvent the use of a human sensory panel, but a technology that can rapidly predict a suite of sensory attributes from one spectral measurement remains unavailable. Using spectra from grape extracts, this novel study aimed to address this challenge by exploring the use of a machine learning algorithm, extreme gradient boosting (XGBoost), to predict twenty-two wine sensory attribute scores from five sensory stimuli: aroma, colour, taste, flavour, and mouthfeel. Two datasets were obtained from absorbance-transmission and fluorescence excitation-emission matrix (A-TEEM) spectroscopy with different fusion methods: variable-level data fusion of absorbance and fluorescence spectral fingerprints, and feature-level data fusion of A-TEEM and CIELAB datasets. The results for externally validated models showed slightly better performance using only A-TEEM data, predicting five out of twenty-two wine sensory attributes with R2 values above 0.7 and fifteen with R2 values above 0.5. Considering the complex biotransformation involved in processing grapes to wine, the ability to predict sensory properties based on underlying chemical composition in this way suggests that the approach could be more broadly applicable to the agri-food sector and other transformed foodstuffs to predict a product's sensory characteristics from raw material spectral attributes. [ABSTRACT FROM AUTHOR]

Although point features have shown their usefulness in classification with Machine Learning, point cloud visualization enhancement methods focus mainly on lighting. The visualization of point features helps to improve the perception of the 3D environment. This paper proposes Multi Feature-Rich Synthetic Colour (MFRSC) as an alternative non-photorealistic colour approach of natural-coloured point clouds. The method is based on the selection of nine features (reflectance, return number, inclination, depth, height, point density, linearity, planarity, and scattering) associated with five human perception descriptors (edges, texture, shape, size, depth, orientation). The features are reduced to fit the RGB display channels. All feature permutations are analysed according to colour distance with the natural-coloured point cloud and Image Quality Assessment. As a result, the selected feature permutations allow a clear visualization of the scene's rendering objects, highlighting edges, planes, and volumetric objects. MFRSC effectively replaces natural colour, even with less distorted visualization according to BRISQUE, NIQUE and PIQE. In addition, the assignment of features in RGB channels enables the use of MFRSC in software that does not support colorization based on point attributes (most commercially available software). MFRSC can be combined with other non-photorealistic techniques such as Eye-Dome Lighting or Ambient Occlusion. [ABSTRACT FROM AUTHOR]

Wood colour metrics are increasingly being used in wood technology and ecology studies. Researchers usually determine the colours of the wood after treatment or in different habitats. There is very little research dedicated to the problem of colour variations among one specific species harvested in different forests or regions. The main purpose of the current research is to reveal and estimate the colour variability of oak species. For this study, a total of 89 samples were taken from the heartwood of seven oak species (Quercus robur L., Quercus cerris L., Quercus rubra L., Quercus pedunculiflora K. Koch., Quercus pubescens Willd., Quercus petraea (Matt.) Liebl., and Quercus palustris Muenchh.). The CIELAB system was used for the assessment of the colour differences. To determine the colour groups and variations, K-means clustering was used. The results show that colour variations do exist. According to the cluster analysis, at least five types of oak wood can be distinguished (because in some clusters, very few samples were present) in the investigated forests. The differences are mainly observed in terms of the lightness (L*) and yellowness (b*). Redness is not a feature by which oak wood differs, but the wood can be brighter or more yellow in some of the samples. The density of the Romanian oaks in the sample does not influence the colour coordinates. The only coordinate affected is a*, but with a very small probability. [ABSTRACT FROM AUTHOR]

Although the effect of thermal modification (TM) on teak wood color is well documented, few studies have been carried out on closed-system processes, and it remains unclear what the effect is of different processes on the same material. This work aimed to verify the effect of closed- and open-system processes of TM on the color of short-rotation teak wood. Thermally modified wood (TMW) was evaluated in a closed system at 160 °C (CS160) and in an open system at 185 °C and 210 °C (OS185 and OS210). We measured the moisture content (initial and final) of the wood and the corrected mass loss (CML). The chemical analyses encompassed the contents of alpha-cellulose, hemicelluloses, lignin, and extractives (total, in acetone and dichloromethane). Wood color was measured before and after TM according to the CIEL*a*b* color space. It was possible to achieve the same color using different processes of thermal modification (CS160 and OS210). TM reduced wood lightness (L*), red–green chromaticity coordinate (a*), and yellow–blue chromaticity coordinate (b*). L* and a* had the biggest and smallest variations, respectively. TMW color was significantly changed, even at the mildest condition tested (OS185, 0.33% CML).

In this study, seventeen faceted gem-quality chrysoberyls exhibiting an attractive canary yellow color were investigated using a variety of gemological, spectral, and chemical methods. Microscopic observation revealed the presence of distinct growth lines and inclusions, including CO2 fluids, carbon, and crystals of mineral such as calcite, quartz, sillimanite, and mica, identified by the Raman spectrum. The FTIR spectra showed the characteristic peaks of 2405 and 2160 cm−1 and a 3223 cm−1 peak in all samples, which can be accompanied by the 3112 cm−1 shoulder, 3301, and 3412 and 3432 cm−1 peaks. The UV-Vis spectra showed an Fe-related peak at 440 nm, along with the 650–660 nm band and the absorption band in the blue zone of visible light. Chemical analyses via EDXRF showed a composition poor in V and Cr and rich in Fe. The spectral and chemical results could help explain the origin of the canary yellow color, which originates from the abundant amount of Fe with very little influence from Cr and V.

Objectives: The aim of this study was to evaluate the accuracy of machine learning regression models in predicting the final color of leucite‐reinforced glass CAD/CAM ceramic veneer restorations based on substrate shade, ceramic shade, thickness and translucency. Methods: Leucite‐reinforced glass ceramics in four different shades were sectioned in thicknesses of 0.3, 0.5, 0.7, and 1.2 mm. The CIELab coordinates of each specimen were obtained over four different backgrounds (black, white, A1, and A3) interposed with an experimental translucent resin cement using a calibrated spectrophotometer. The color change (CIEDE2000) values, as well as all the CIELab values for each one of the experimental groups, were submitted to 28 different regression models. Each regression model was adjusted according to the weights of each dependent variable to achieve the best‐fitting model. Results: Different substrates, ceramic shades, and thicknesses influenced the L, a, and b of the final restoration. Of all variables, the substrate influenced the final ceramic shade most, followed by the ceramic thickness and the L, a, and b of the ceramic. The decision tree regression model had the lowest mean absolute error and highest accuracy to predict the shade of the ceramic restoration according to the substrate shade, ceramic shade and thickness. Clinical Significance: The machine learning regression model developed in the study can help clinicians predict the final color of the ceramic veneers made with leucite‐reinforced glass CAD/CAM ceramic HT and LT when cemented with translucent cements, based on the color of the substrate and ceramic thicknesses. [ABSTRACT FROM AUTHOR]

Fungi and bacteria are important causes of damage to historical textiles. Many methods are used to resist innate damage in historical textiles. The study aim was to use an innovative method that loaded a mahogany plant extract onto natural chitosan and gelatin nanocomposite polymers to prepare chitosan / mahogany plant extract composite and gelatin mahogany plant extract nanocomposite and evaluate their potential for protecting historical textiles from biological damage. The fungi and bacteria found on historical textile samples were identified by biochemical methods. We performed an antifungal activity assessment of the mahogany—natural chitosan and mahogany—gelatin polymers to study the effect of these materials on the mechanical, chemical, and optical properties of dyed linen textiles. New linen fabrics dyed with madder, turmeric, and pomegranate were mordanted with alum, copper, and iron mordants. These materials were applied to dyed linen fabrics, and then the treated linen was artificially aged. The mechanical, chemical, and optical characteristics of the dyed linen fabric were examined by scanning electron microscopy, Fourier-transform infrared spectroscopy, CIELab, the tensile strength and elongation test, and the air permeability test. Mahogany – chitosan was more effective than mahogany – gelatin as an antifungal and antibacterial treatment of dyed linen and caused fewer changes in the mechanical, chemical, and optical characteristics. The mahogany – chitosan composite is recommended for preservation of historical linen textiles. [ABSTRACT FROM AUTHOR]

This in vitro study investigated the extrinsic tooth-whitening effect of bleaching products containing polyphosphates on the dental enamel surface compared to 10% carbamide peroxide (CP). Eighty human molars were randomly allocated into four whitening-products groups. Group A (control) was treated with 10% CP (Opalescence). The other groups with non-CP over-the-counter (OTC) products were group B = polyphosphates (iWhiteWhitening-Kit); group C = polyphosphates+fluoride (iWhite-toothpaste); and group D = sodium bicarbonate (24K-Whitening-Pen). L*, a*, b* color-parameters were spectrophotometer-recorded at baseline (T0), one day (T1), and one month (T2) post-treatment. Changes in teeth color (ΔEab) were calculated. Data were analyzed using ANOVA and the Bonferroni test (α = 0.05). Groups A, B, and D showed significant differences in ΔL*&Δa* parameters at T1, but not in Δb* at T0. Group C showed no difference for ΔL*, Δa*, Δb* at T0 and T1. Group A showed differences for ΔL*, Δa*, Δb*, at T2, while groups B, C, and D had no difference in any parameters at T0. At T1, ΔEab values = A > D> B > C (ΔEab = 13.4 > 2.4 > 2.1 > 1.2). At T2, ΔEab values increased = A > B > C > D (ΔEab = 12.2 > 10.6 > 9.2 > 2.4). In conclusion, the 10% CP and Biomimetic polyphosphate extrinsic whitening kit demonstrated the highest color change, while simulated brushing with dark stain toothpaste and a whitening pen demonstrated the lowest color change at both measurement intervals. [ABSTRACT FROM AUTHOR]

Some color images primarily comprise specific hues, for example, food images predominantly contain a warm hue. Therefore, these hues are essential for creating delicious impressions of food images. This paper proposes a color image enhancement method that can select hues to be enhanced arbitrarily. The current chroma is considered such that near achromatic colors are not over-enhanced. The effectiveness of the proposed method was confirmed through experiments using several food images. [ABSTRACT FROM AUTHOR]

This study analyzes the color combinations composed by the Russian avant-garde artist Mikhail Matyushin and his disciples for the Reference Book of Color (1932), summarizing their experimental research on the psychophysiology of color perception. Having extracted 90 colors from the 34 hand-painted charts of the book's first edition, we mapped these colors into CIELAB and CIELCh color space to identify their chromatic characteristics (hue, lightness, and chroma) and their combination criteria. We demonstrate graphically that each of Matyushin's color triads has a similar "geometry" in CIELAB color space and on the color circle, with the "intermediary" color much closer to the environment background color than to the main color. We conclude that the revealed patterns of these relationships are identical in all four sections of the Reference Book and reflect underlying principles of Mathyshin's theory of color as well as fundamental aspects of human perception. The analysis presented in this paper will facilitate opportunities for artists, architects, designers, and other color professionals to use Matyushin's original color charts and incorporate Matyushin's style in creating their own triads. [ABSTRACT FROM AUTHOR]

This study aimed to assess two methodologies (K/S and Krzywicki methods) based on reflectance measurements for estimating the myoglobin (Mb) meat redox forms (deoxymyoglobin, DMb; oxymyoglobin, OMb; and metmyoglobin, MMb), determining their relationship with the CIE color. Different Mb redox reference values were evaluated, and their proportions were estimated in beef longissimus muscle during blooming and display storage. The better reference standards for use in the K/S method were defined as surface reading immediately after meat cutting for 100 % DMb and reading one day after oxidation with potassium ferricyanide for 100 % MMb. Despite being highly correlated (r > 0.92), the K/S and Krzywicki methods produced different pigment proportions. The OMb and MMb obtained by the K/S method were much more consistent with the expected proportion of these pigments during the blooming and oxidation processes. The yellowness (b *) and hue (h) values best described the changes during blooming and were related with OMb formation, while redness (a *) and chroma (C *) were related to the changes in beef discoloration associated with MMb accumulation. This research highlights the importance of analyzing both pigment proportions and colorimetric data in meats, providing unique perspectives on the slight yet crucial changes in meat color. • Krzywicki's convenience versus K/S's accuracy and standards. • Establishment of reliable standards for DMb and MMb for K/S. • CIE color parameter shifts during blooming and storage. • DMb highest in freshly cut than dithionite-treated samples. • Display time affects MMb proportion and color stability. [ABSTRACT FROM AUTHOR]

Increasing consumer demand for high-quality wines required the introduction of more comprehensive monitoring indicators for quality management, necessitating winemakers to strive for rapid, real-time, and affordable monitoring tools during winemaking. This study investigated the feasibility of cost-efficient and easy-to-implement ultraviolet-visible (UV-Vis) spectroscopy combined with chemometric methods to predictively monitor the evolution of wine color and phenolics throughout commercial fermentation. Fermentations on a winery scale were carried out with a daily analysis of the UV-Vis spectra, color, and phenolics. Furthermore, characteristic wavelengths were established by a self-compiled Python program to reduce redundancy in spectra. The optimized partial least squares (PLS) model predicted well with a residual prediction deviation (RPD) greater than 2.54, and the robustness was further verified by a robust external Bland-Altman method. UV-Vis spectroscopy can achieve objective monitoring of the practical fermentation profile, which can better help winemakers make decisions to improve wine quality and consistency. [Display omitted] • Propose a real-time and low-cost method for quality control of winemaking in practice. • The PLS models can predict well the phenolics and color only by UV-Vis spectroscopy. • Key spectral variables can be screened by a self-compiled Python program. • The accuracy of the optimal model was verified externally by Bland-Altman method. • The experiments were carried out on both winery and laboratory scales. [ABSTRACT FROM AUTHOR]

In the present study, the colour and C:N ratio of quinoa flours pigmented with M. purpureus supplemented with monosodium glutamate and sodium chloride were evaluated during 14 days of fermentation. The best values of L*, a* and b* corresponded to the eighth day. This research showed that the pigmented flour produced by solid state fermentation of quinoa by M. purpureus showing variations in the colour red along with the C:N ratio during the fermentation time, resulting in a product with good visual sensory attributes that can be used to develop new naturally pigmented products with potential functional characteristics.

The better adaptation of autochthonous grape varieties to environmental changes is increasing the interest on them. Previous studies on Vitis vinifera L. cv Rufete, the flagship of DOP “Sierra de Salamanca”, demonstrated its phenolic potential to produce quality wines. The present study aims at discovering flavonoid (HPLC-DAD-MSn) and colorimetric (CIELAB) varietal markers in commercial Rufete wines (RW) that could be employed to discriminate them from those made with other varieties or mixtures. Compared to Tempranillo wines (TW), RW showed lower phenolic contents, with lower proportions of anthocyanins and flavonols but greater of flavanols. Principal Component Analysis applied to flavonoid and chromatic variables allowed varietal separation of the samples along PC2, which was mostly driven by %total prodelphinidins, %oligomeric procyanidins and Cab* (greater in TW) and by %monomeric procyanindins and L* (greater in RW) and, additionally, by the proportions of A-type vitisins, acetaldehyde-related pigments, quercetin 3-O-glucuronide and Quercetin/Myricetin ratio (all greater in RW). The results of the present study show that the typicity of Rufete grapes is quite preserved in the wines made with up to 95% of Rufete and 5% of Tempranillo grapes or wines and independently of the enological practices of the different wineries.

Purpose: To verify the color change and contrast ratio of resin composites after curing and after 30 days of storage in water. Methods: Dentin A2 shades of different light-cured dental resin composites (Vittra APS, FGM, Brazil; Z350 XT, 3M ESPE, EUA; Tetric N-Ceram, Ivoclar Vivadent, Liechtenstein, and Charisma Diamond, Heraeus Kulzer, Germany) were tested. Ten rounded specimens (8 mm × 2 mm) were prepared for each material. Reflectance for all samples was obtained using a spectrophotometer (Minolta CM 3700d, Konica Minolta, Japan) before curing, immediately after curing, and after 30 days of storage in water. The color change (ΔE*lab) and contrast ratio (CR) data were analyzed using a one-way analysis of variance with Tukey's and paired t-tests (α = 1%). Results: For all materials tested, significant color changes were noticeable after curing and after 30 days in water (p 0.01). Conclusion: The CR values and color changes after curing and 30 days of storage in water varied depending on the material tested. This study corroborates the clinical practice of curing a small amount of unpolymerized resin composite on the tooth surface to select the desired shade before undertaking esthetic restorative procedures.

With its high protein content, forage soybean is an important legume roughage that should be included in animal rations. However, the traditional silage production of pure soybean as forage is limited by its high protein content. The aim of the study was to determine the effect of the duration of storage and soybean variety on some quality parameters and color change in pure soybeans silage. Two soybean forage varieties (Yemsoy and Yesilsoy) as the main factor were harvested in the appropriate harvesting period and with an appropriate technology, and after wilting the soybean plants were ensilaged without any additives in small bales of 40-50 kg. The bales were stored for 5 lengths of storage (20, 40, 60, 80, and 100 days), which was the second experimental factor. The silage samples as 3 replications were collected at the end of the storage period to evaluate dry matter (DM), pH, crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), relative feed value (RFV), digestible dry matter (DDM), dry matter intake (DMI), fleig score (FS) and CIELab color scale (L, a, b). The data from 2 years were processed statistically in randomized blocks according to a split plot design. No statistical difference between the duration of storage and varieties in terms of RFV was observed. However, it was determined that the pH value was statistically lower (p<0.01) in the soybean bale silage stored for 80 and 100 days. In addition, it was determined that silages stored for 100 days were higher (p<0.01) in terms of the brightness value L. It is evident that high quality and bright colored roughage can be obtained in soybean silage stored for 80 and 100 days without any additives. [ABSTRACT FROM AUTHOR]

Photoselective nets are used to protect horticultural plants from sunburn and prolong the cropping period in conditions of excess light. In this work, we studied the influence of four photoselective shading nets (Pearl 30, Red 30, Silver 30, Red 40), a standard blackcolored net (Black 35), and a control (no cover) on the evolution of color during the ripening of two types of pepper, namely, Lamuyo and California. For this purpose, the evolution of the colors of the fruit was followed from the beginning of their formation until the harvest, and was correlated with the total radiation and the temperature. The plant material used were peppers of the California type -cultivars Bendigo and Cayetano- and of the Lamuyo type, cultivars Alcudia and Pompeo. The results showed that the rate of change of the pepper coloration depended on the net used in the greenhouse. The speed of the change in color from green to red was more dependent on the cultivar and the total radiation, as conditioned by the different photoselective nets, than on the type of pepper. The greatest differences were between the control (without a net) and the black net, the increase in the red color of the peppers being faster in the former. Radiation values below 75 W m-2 or greater than 110 W m-2 negatively affected the yield. The temperature below the net was not affected significantly by the type of net, and thus its effect on the different cultivars was similar. [ABSTRACT FROM AUTHOR]

Salvia is the largest genus in the Lamiaceae with more than 1000 species. The species S. coccinea used in this study has naturalized in the southeastern United States and is an important plant for pollinators. This project aimed to improve phenotypic characteristics of S. coccinea for use in the landscape by selecting for increased petal size and unique petal color. Two elite accessions were selected for hybridization using the pedigree method. One selection displayed compact habit with bicolored coral and white flowers, while the other was slightly larger with solid red flowers. Selections were made based on improved flower color and larger petal size. The breeding program achieved a 25% increase in petal width and a more vivid petal color for the coral bicolored selections. Additionally, a 60% increase in petal width was achieved for red flowers. These novel selections are attractive plants for the landscape, displaying improved ornamental value and supporting local pollinator populations. [ABSTRACT FROM AUTHOR]

The early stages of the United States Department of Agriculture (USDA) Louisiana commercial sugarcane breeding program involve planting large numbers of genetically unique seedlings that require time and resources to evaluate. Selection is made quickly, is subjective, and related to the appearance of yield and vigor. Remote sensing techniques have been used to predict yield of several crops over large areas using areal images. To understand selection preferences better and if remote sensing techniques could be used to increase efficiency, twelve sugarcane seedling families each having approximately 263 seedlings were planted in two replications at the USDA-ARS Ardoyne farm. Stalk height, number and diameter ratings were taken on 50 stools of each replication of each family. Red-Green-Blue images were taken of the seedling field in plant cane and first ratoon before selection. Spectral indices were derived from the images for each plot. Height had the largest influence on visual selections of the field measurements evaluated. Several spectral indices such as the Green Area (GA) correlated highly with important traits including Height (>0.80), selection rates (>0.70), and Brix (>0.60). The results show the potential for seedling evaluation by remote sensing methods. [ABSTRACT FROM AUTHOR]

Color constancy is something we take for granted. An apple appears red despite monumental changes in the intensity and spectral balance of illumination. There are many components to the human visual system that make this illusion possible. Nonetheless, the system is imperfect. Objects will change apparent color under different illumination. The CIELAB color space allows for the computation of color values under any illuminant. CIELAB values will, in general, change as the illuminant changes. It would be natural to assume that these changes in CIELAB values would agree with the apparent color change that a human would experience. But the chromatic adaptation built into CIELAB is known to be less than optimal due to an imperfect emulation of how the adaptation process is performed in the human visual system. As a result, at least part of the illuminant color change implied by the CIELAB values is an artifact of this imperfect emulation. This paper investigates the magnitude of this artifact by comparing color changes implied by CIELAB with color changes in a color system that mimics CIELAB, except that it more closely emulates the human visual system. The difference between the two estimates of color change is assumed to be an artifact of CIELAB's poor emulation of the chromatic adaptation process. As color manufacturers are dealing with a wider spectrum of illumination sources, they may wish to consider the issue of color constancy; what colors and what formulations of colors exhibit better color constancy? Can CIELAB be used to quantify this? Or are color spaces that are based on LMS rather than XYZ more appropriate? [ABSTRACT FROM AUTHOR]

Colorimetric sensors play a crucial role in promoting on-site testing, enabling the detection and/or quantification of various analytes based on changes in color. These sensors offer several advantages, such as simplicity, cost-effectiveness, and visual readouts, making them suitable for a wide range of applications, including food safety and monitoring. A critical component in portable colorimetric sensors involves their integration with color models for effective analysis and interpretation of output signals. The most commonly used models include CIELAB (Commission Internationale de l'Eclairage), RGB (Red, Green, Blue), and HSV (Hue, Saturation, Value). This review outlines the use of color models via digitalization in sensing applications within the food safety and monitoring field. Additionally, challenges, future directions, and considerations are discussed, highlighting a significant gap in integrating a comparative analysis toward determining the color model that results in the highest sensor performance. The aim of this review is to underline the potential of this integration in mitigating the global impact of food spoilage and contamination on health and the economy, proposing a multidisciplinary approach to harness the full capabilities of colorimetric sensors in ensuring food safety., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Sour cherry is one of the most important horticultural crops in the Hungarian market. Its flavour combination makes it ideal for fresh consumption as well as canned products. The Hungarian and European markets have requested for new varieties to be introduced, making the evaluation of breeding and prebreeding material a crucial point. A total of 30 sour cherry accessions from the genebank collection were investigated for their potential inclusion into the breeding program. The main aim of the study was to identify candidates for future breeding programs, selecting their colour profiling and total polyphenolic content (TPC). This study follows the antioxidant activity of cherry species by determining the total content in polyphenols. Polyphenols are found in higher concentration in cherries when compared to other plants and have been identified as free radical scavengers, which are useful to prevent the occurrence of several diseases. Furthermore, TPC has been observed as a contributor of bitterness, acidity, colour, flavour, odour, and oxidative stability. The accessions were evaluated for their colour, fruit weight, flavour profile, firmness, and TPC. Colorimetric data were compared among four methods to illustrate to the Hungarian breeders which of the available approaches is the most accurate for sour cherry breeding. Results suggested that several accessions appear relevant for the breeding program, such as ‘Pipacs 1′, ‘Bosnyák’, ‘Hortenzia Királynője’, and ‘Mogyoródi Kései’. The total polyphenolic content was highest in ‘Pipacs1′ and lowest in ‘Kántorjánosi 3′. ‘Pipacs 1′ and ‘Hortenzia Királynője’ had interestingly high acidity content and light to very light fruit colours. ‘Bosnyák’ had a deep and dark colour with high soluble sugar content. ‘Mogyoródi Kései’ appears to have the biggest fruit. All mentioned varieties will be included in future breeding programs.

Nowadays, the development of naturalness as a concept is illustrated in the oenological field by the development of wine produced with lower inputs, sometimes even without any addition of SO2 throughout the winemaking process, up to the bottling stage. Despite the increase in the offer of these wines, they remain poorly explored in the literature and require characterization. This study was developed to evaluate the color of Bordeaux red wines without SO2 addition using colorimetric and polymeric pigments analysis. From a batch of commercial Bordeaux red wines with and without SO2 addition, and experimental wines produced from homogenous grapes according to different winemaking processes, colorimetric analyses (CIELab and color intensity (CI)) revealed a large difference in wine color depending on the presence or absence of SO2. Indeed, wines without SO2 were significantly darker and presented with a deeper purplish color. According to these observations, polymeric pigments were quantified using UPLC-DAD/ESI QTof, and a higher concentration of polymeric pigments bound by the ethylidene bridge was observed in wines without SO2. This correlated with differences observed for CIELab and CI. Finally, a comparison with polymeric tannins bound by ethylidene bridge was made and revealed that no differences were observed between wines with and without added SO2. This underlines the affinity difference between tannins and anthocyanins to react with acetaldehyde to form ethylidene bridges.

The classification of color is important in the management and evaluation of red wine color. Nevertheless, current reports have not given a sound solution. A novel scheme for the quantitative classification of red wine color from the perspective of micro and macro levels was proposed in this work. The overall color performance of 119 representative red wine samples was visualized and classified into 125 micro-classifications according to the partition of the chromaticity and lightness of the wine color. Considering the evolution of red wine color, quantitative macro-classification of the color of the wine samples was explored, and six macro-classifications were obtained. These few classifications determine the extent of aging and aging potential of colors between different red wines well. The performance of this approach was further verified by another set of 56 red wine samples. This efficient and easy-to-implement approach is expected to be helpful in the digital and visual color management, control, evaluation, comparison, and prediction of red wines.

Simple Summary: R-ice is one of the world's most important staples; a growing population and declining rates of growth in rice yields will present significant challenges ahead. After the heading stage, the photosynthetic ability of the flag leaf has a great effect on the yield of rice, and this ability can be evaluated by leaf color, chlorophyll content, quantum yield, etc. Our purpose was to screen candidate genes that affect photosynthetic efficiency through QTL mapping analysis and predict their function through protein interaction and homology sequence analysis. The results suggest that OsbHLHq11 may be involved in chlorophyll accumulation and enhancing photosynthetic efficiency, which may lead to high yields. Photosynthesis is an important factor in determining the yield of rice. In particular, the size and efficiency of the photosynthetic system after the heading has a great impact on the yield. Research related to high-efficiency photosynthesis is essential to meet the growing demands of crops for the growing population. Chlorophyll is a key molecule in photosynthesis, a pigment that acts as an antenna to absorb light energy. Improvement of chlorophyll content characteristics has been emphasized in rice breeding for several decades. It is expected that an increase in chlorophyll content may increase photosynthetic efficiency, and understanding the genetic basis involved is important. In this study, we measured leaf color (CIELAB), chlorophyll content (SPAD), and chlorophyll fluorescence, and quantitative trait loci (QTL) mapping was performed using 120 Cheongcheong/Nagdong double haploid (CNDH) line after the heading date. A major QTL related to chlorophyll content was detected in the RM26981-RM287 region of chromosome 11. OsbHLHq11 was finally selected through screening of genes related to chlorophyll content in the RM26981-RM287 region. The relative expression level of the gene of OsbHLHq11 was highly expressed in cultivars with low chlorophyll content, and is expected to have a similar function to BHLH62 of the Gramineae genus. OsbHLHq11 is expected to increase photosynthetic efficiency by being involved in the chlorophyll content, and is expected to be utilized as a new genetic resource for breeding high-yield rice. [ABSTRACT FROM AUTHOR]

The alcoholic beverage industry has grown exponentially in terms of the production of alcohol-containing products in an artisanal manner. Thus, it is proposed to implement an agroindustrial production alternative by making fruit wine from curuba (Passiflora mollissima) using a Saccharomyces Cerevisiae (Var. Bayanus) yeast strain. Three phases were developed; the first consisted of obtaining and fermenting the curuba pulp; the second phase included physicochemical and microbiological characterization, evaluating parameters such as pH, acid-base titration, soluble solids, color, viscosity, yeast count by deep seeding on YGC agar and LAB count on MRS agar to verify malolactic fermentation; finally, sensory analysis was performed through a quantitative descriptive analysis (QDA) in solitary and paired. The result obtained was a beverage with a pH of 3,14±0,02, a viscosity of 2,31±0,02 cP, soluble solids content of 7,65±0,07 °Brix and an alcohol content of 12,91±0,19 v/v. Thus, the study demonstrates that curuba has a high biotechnological potential in the elaboration of fermented beverages, offering an additional alterna- tive for the elaboration and commercialization of new products in the department of Huila (Colombia). [ABSTRACT FROM AUTHOR]

Copyright of Annals of Warsaw University of Life Sciences - SGGW, Forestry & Wood Technology is the property of Wydawnictwo SGGW and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current color-difference formulas were developed based on 2D samples and there is no standard guidance for the color-difference evaluation of 3D objects. The aim of this study was to test and optimize the CIELAB and CIEDE2000 color-difference formulas by using 42 pairs of 3D-printed spherical samples in Experiment I and 40 sample pairs in Experiment II. Fifteen human observers with normal color vision were invited to attend the visual experiments under simulated D65 illumination and assess the color differences of the 82 pairs of 3D spherical samples using the gray-scale method. The performances of the CIELAB and CIEDE2000 formulas were quantified by the STRESS index and F-test with respect to the collected visual results and three different optimization methods were performed on the original color-difference formulas by using the data from the 42 sample pairs in Experiment I. It was found that the optimum parametric factors for CIELAB were k L = 1.4 and k C = 1.9, whereas for CIEDE2000, k L = 1.5. The visual data of the 40 sample pairs in Experiment II were used to test the performance of the optimized formulas and the STRESS values obtained for CIELAB/CIEDE2000 were 32.8/32.9 for the original formulas and 25.3/25.4 for the optimized formulas. The F-test results indicated that a significant improvement was achieved using the proposed optimization of the parametric factors applied to both color-difference formulas for 3D-printed spherical samples. [ABSTRACT FROM AUTHOR]

According to the current legal regulations, the flags of 8 of the 19 autonomous communities and cities in Spain have only qualitative specifications of their colors. We have performed quantitative color measurements under fixed experimental conditions (e.g. illuminant D65, CIE 1964 standard colorimetric observer) for 3 collections of the 19 mentioned flags: One acquired by internet and two existing in high institutions of the Spanish State in Madrid (Supreme Court and Constitutional Court). The 52 main colors of the flags of the Supreme Court and Constitutional Court are relatively similar (average color difference of 6.2 CIELAB units). Therefore, we propose their average colors (with the exception of the blue color of the diagonal stripe of the flag of Galicia and the red and green stripes of the flag of La Rioja), with a tolerance of 10 CIELAB units, as a reference for future studies and standardization. The average color difference between our proposal and the colors of the purchased flags or those specified in current legislation is very high (about 20 CIELAB units). Most colors of the flags in the Supreme Court and Constitutional Court are located in 6 regions of the CIELAB color space we can name as white, black, red, yellow, green and blue. In all our color comparisons of flags from different collections, hue difference was the smallest component (<20%) of total CIELAB color difference. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería (0121-750X) is the property of Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Ananas comosus var. bracteatus is a colorful plant used as a cut flower or landscape ornamental. The unique foliage color of this plant includes both green and red leaves and, as a trait of interest, deserves investigation. In order to explore the pigments behind the red section of the chimeric leaves, the green and red parts of chimeric leaves of Ananas comosus var. bracteatus were sampled and analyzed at phenotypic, cellular and molecular levels in this study. Results The CIELAB results indicated that the a* values and L* values samples had significant differences between two parts. Freehand sections showed that anthocyanin presented limited accumulation in the green leaf tissues but obviously accumulation in the epidermal cells of red tissues. Transcriptomic and metabolomic analyses were performed by RNA-seq and LC-ESI-MS/MS. Among the 508 identified metabolites, 10 kinds of anthocyanins were detected, with 6 significantly different between the two samples. The cyanidin-3,5-O-diglucoside content that accounts for nearly 95.6% in red samples was significantly higher than green samples. RNA-Seq analyses showed that 11 out of 40 anthocyanin-related genes were differentially expressed between the green and red samples. Transcriptome and metabolome correlations were determined by nine quadrant analyses, and 9 anthocyanin-related genes, including MYB5 and MYB82, were correlated with 7 anthocyanin-related metabolites in the third quadrant in which genes and metabolites showing consistent change. Particularly, the PCCs between these two MYB genes and cyanidin-3,5-O-diglucoside were above 0.95. Conclusion Phenotypic colors are closely related to the tissue structures of different leaf parts of Ananas comosus var. bracteatus, and two MYB transcription factors might contribute to differences of anthocyanin accumulation in two parts of Ananas comosus var. bracteatus chimeric leaves. This study lay a foundation for further researches on functions of MYBs in Ananas comosus var. bracteatus and provides new insights to anthocyanin accumulation in different parts of chimeric leaves.

Salvia is the largest genus in the Lamiaceae with more than 1000 species. The species S. coccinea used in this study has naturalized in the southeastern United States and is an important plant for pollinators. This project aimed to improve phenotypic characteristics of S. coccinea for use in the landscape by selecting for increased petal size and unique petal color. Two elite accessions were selected for hybridization using the pedigree method. One selection displayed compact habit with bicolored coral and white flowers, while the other was slightly larger with solid red flowers. Selections were made based on improved flower color and larger petal size. The breeding program achieved a 25% increase in petal width and a more vivid petal color for the coral bicolored selections. Additionally, a 60% increase in petal width was achieved for red flowers. These novel selections are attractive plants for the landscape, displaying improved ornamental value and supporting local pollinator populations.

Abstract The potential use of colorimetric sensors has received significant attention due to its feasibility for use in various applications. After reacting with a sample, the image of the colorimetric sensor can be captured and converted into digital data using several different color models. The analytical data can then be processed with various chemometric methods. This research study investigated the predictive performance of calibration models established using color models commonly used in analytical chemistry including RGB, CMYK, HSV and CIELAB. A total of eight commercially available colorimetric sensors were used to determine the presence of manganese (Mn2+), copper (Cu2+), iron (Fe2+/Fe3+), nitrate (NO3 –), phosphate (PO4 3–), sulfate (SO4 2–), as well as total hardness and pH values. As external validation tests, real water samples collected in Chiang Mai, Thailand were used. Based on the resulting data obtained using the synthetic test samples, the color that was most similar to the appearing color of the chemical sensor could offer satisfactory results. However, it was not always the case especially when the strips composed of multiple colorimetric sensors or sensor array were used. When tested with external validation, the predictive performance could be improved using appropriate data preprocessing and, in this research study, a normalization method was recommended to guarantee the accuracy of the calibration models.

• Rosé wine color, aromas and phenolics were highly impacted by storage conditions. • Flint bottle under fluorescent light at 22 °C was the most detrimental condition. • Wines stored in darkness at 12 °C showed the smallest changes in composition. • Panelists discriminated the wines based on storage conditions after six months. The majority of rosé wines are bottled in clear bottles as color is an important factor in consumer preference. Post-bottling wine can be exposed to UV–visible light and temperature fluctuations resulting in quality degradation. This study investigated the impact of bottle color (flint and antique green), light exposure (darkness, LED and fluorescent bulb), and temperature (12 °C and 22 °C) on rosé wine quality using a full factorial design with three different wines (Grenache, Pinot noir and Zinfandel). The impact on chemical composition, color, phenolics and aromatics was determined. Projective mapping was carried out for sensorial analysis. Changes in the aromatics, color and phenolic composition were detectable after three months and more noticeable after six months of storage. Overall, all variables studied impacted rosé wine characteristics significantly. However, higher temperature in combination with clear glass bottles under fluorescent light were the most detrimental conditions. [ABSTRACT FROM AUTHOR]