CIELAB System Research Articles

Correlation Analysis of Subjective and Objective Texture Properties: Color and Heterocyclic Amine Content of Grilled Chicken Breast Fillet

The present study discusses the technofunctional properties (color, texture) of grilled chicken with both objective (colorimeter, texture profile) analysis and subjective (sensory) analysis. Besides them, the total content of potentially carcinogenic heterocyclic amines (HCAs) was also monitored by the applied grilling time–temperature combinations. The same samples were analyzed during the heat treatment of chicken breast samples for 5–15 min at 150–230 °C on an electric contact grill. The grilling variables included the effect of skin cover. Among the structural parameters, hardness exhibited a significant difference between the groups of skin-covered and not-covered ones, and in this case, a linear connection was also found with the time and temperature values, respectively. The structural parameters obtained by sensory and instrumental analysis were compared to each other. In addition, the structural parameters were compared to the color ones (sensory, color according to the CIELAB system: brightness, redness, and yellowness) and to the total HCA content. In the case of closed grilling, sensory-evaluated parameters such as juiciness and tenderness showed a strong negative correlation to instrumentally measured hardness (R = −0.879; −0.749) and chewiness (R = −0.872; −0.718) due to the water loss from the increase in grilling temperature and time. The total HCA content positively correlated to chewiness (R = 0.789). The sensory color parameter and the brightness had a strong connection with juiciness (R = 0.738; 0.723), hardness (R = −0.795; −0.706), and chewiness (R = −0.843; −0.818); redness showed positive correlation to cohesiveness (R = 0.764) and chewiness (R = 0.829). Accordingly, juiciness and chewiness showed a connection to the total HCA levels, which makes it possible to carry out further research on instrumental and sensory parameters that may predict the formation of hazardous amounts of carcinogenic heterocyclic amines.

Evaluation of wash colour strength of a printed garment with flexible filaments on 3D printers

The research aims to evaluate the solidity of the washing colour of a garment printed with flexible filaments on 3D printers. Three groups of factors have been selected: Anet A8 and M3D Crane Quad printer, temperature (49° and 71°C) and flexible filaments TPE (thermoplastic elastomer) and TPU (polyurethane thermoplastic), framed in the factorial design, type applied of 10 units per combination of factors in a total of 80 sampling units, using Girowah equipment according to the technical standard AATCC TM61-2020. The results show that the printer factors Anet A8 and M3D Crane Quad with the CIELab and CMC (2:1) discolouration system exceed 50% in both the tolerances of the value 1. About the temperature factor (49° and 71°C), which exhibits a discolouration of 1.06 in CIE94 and 1.36 in CMC, it is determined that the combination with better resistance to discolouration of solidity at washing (CIE94 - 49°C) compared to CMC (2:1) better establishes the visual and technical concordance of the solidity of colour. As regards flexible filament types: TPE and TPU, the results show us that the colour tolerance assessments (CIELab CIE94) and (CMC (2,1)) prove that the TPE filament has greater resistance to the discoloration of the 3D-printed garment at different temperatures. In conclusion, the solidity of colour washing in a printed garment with flexible filaments in a 3D printer causes discolouration by the minimum, be it the factors of printer type, filament, and temperature. There is a need for analysis with other values and it remains open to other research.

Can wheel polishers improve surface properties and color stability of monochromatic resin composites?

BackgroundTo overcome the color layering procedure, monochromatic resin composites have been introduced. However, little is known about their polishability, gloss and color stability. This study aimed to investigate the surface roughness, gloss, and color change of monochromatic resin composites polished with wheel systems after being immersed in coffee.Materials and methodsOmnichroma, Zenchroma, Essentia Universal, Charisma Diamond One and NeoSpectra ST were used to obtain 120-disc samples of 8 × 2 mm. Only one side of the sample was polished with Twist Dia (TWD) or Nova Twist (NOV). The samples were examined for surface roughness, gloss, and color (ΔE and ΔE00) before and after 7 days of immersion in coffee and subsequent repolishing. The discs were examined via SEM. Surface roughness and gloss values were analyzed using ANOVA, Tukey and Pearson correlation tests. ΔE and ΔE00 values were evaluated using T tests, multivariate ANOVA, and Dunnett’s post-hoc tests.ResultsFor TWD groups, the smoothest material was Omnichroma (p < 0.05), while for NOV groups, it was Omnichroma and Zenchroma. Omnichroma was the glossiest, while Charisma Diamond One was the least glossy. In TWD groups, Charisma Diamond One and Essentia Universal were the most discolored, while Zenchroma and Omnichroma were the least. For NOV groups, Essentia Universal and Charisma Diamond One were the most discolored, while NeoSpectra ST, Omnichroma and Zenchroma were the least. After repolishing, Charisma Diamond One did not reach the level of ΔE < 2, while the other groups showed values below. Color evaluation with the CIELab and CIEDE2000 systems revealed similar results for the TWD groups after post-staining.ConclusionsSmooth and glossy surfaces could be achieved with the wheel system regardless of the composite resin. Repolishing after discoloration ensures that the color recovery is below the acceptable limit. Color evaluations with CIELab and CIEDE2000 yielded similar results.

Evaluation of the antioxidant potential for three essential oils on the properties of wood pulp paper

Purpose This study aims to determine the efficiency of three types of essential oils (EOs) as antioxidants on wood pulp paper samples: camphor oil, clove oil and lavender oil. Because of the detrimental influence of the oxidation process on wood pulp paper, this type of paper suffers significant disintegration. Design/methodology/approach The evaluation methodology is based on scanning electron microscope and three directions laser microscope, the hydrogen ion concentration measurement, color change measurement using the CIELAB system and infrared spectrum analysis, as well as investigating the mechanical properties of paper as represented by tensile and elongation to determine Young’s modulus values. Findings According to the findings, camphor was an effective antioxidant for paper samples, protecting them from the damaging effects of oxidation and the impact of artificial aging processes while also improving the mechanical properties of paper. Originality/value This paper emphasizes the concept of using environmentally friendly materials derived from EOs, owing to their ease of application, lack of environmental impact, distinctive properties, low cost and distinctive properties in both curative and preventive conservation of paper manuscripts.

The colour stability of 3D-printed, non-invasive restorations after 24 months in vivo – esthetically pleasing or not?

ObjectivesThe aim of the present prospective study was to evaluate the colour stability of 3D-printed non-invasive restorations after 24 months in vivo. MethodsThe study included 29 patients, who received 3D-printed restorations made of a computer-aided design (CAD) / computer aided-manufacturing (CAM) hybrid material (n = 354). Restoration colour of 190 restorations was measured using a spectrophotometer. By applying the CIELAB system, *L (lightness), a* (red-green) and b* (blue-yellow) values were recorded. An evaluation of the colour differences (ΔE) after 6, 12 and 24 months was conducted. ResultsAnalysis of colour differences of 3D-printed restorations showed continuous discolouration of the restorations. After one year 34 % and after two years 18 % of the restorations were rated alpha or bravo, indicating no or hardly visible colour change. After two years, 54 % of the evaluated restorations yielded a colour difference with ΔE > 6.8 (delta). More than 82 % of the evaluated restorations showed values between ΔE 3.8 – 6.8 (charlie) and ΔE ˃ 6.8 (delta) after two years. Conclusions3D-printed non-invasive restorations showed an overall reduced colour stability after 24 months in vivo. Clinical SignificanceThe present study provides first clinical data regarding 3D-printed restorations. These restorations are recommended for a wearing time of about 6 months.

Molecular tool for efficient breeding of DOMINANT Greenshell laying hens and significant refinement of phenotypic selection focused on eggshell color

In recent decades, interest in non-traditionally colored eggs has increased. For breeders, this market interest means breeding lines of laying hens that lay eggs of varied colors, such as the blue-green eggshells (Dominant Greenshell) in this study. This study presents the results of genotyping the polymorphism of the O locus responsible for shell coloration and photometric measurement of eggshell color based on the CIELAb system, which was carried out on the unique Czech breeding population Dominant Greenshell. The aim was to use a combination of phenotyping using the CIELab System method and genotyping of the O locus using the end-point PCR approach with the main focus on the accuracy of distinguishing shell color genotypes, streamlining the selection of dominant homozygotes in the O locus, optimizing this technology for the most efficient and cost-effective selection procedure in practical hen breeding. The optometric method was able to reliably distinguish only dominant and recessive phenotypes and eliminate from the population only undesirable recessive homozygotes with a white colored shell. The parameter a* (redness/greenness) from the CIELab color space turned out to be absolutely key for distinguishing dominant and recessive phenotypes. Using the CART methodology, a classification tree built on discriminating optometric characteristics a-blunt was obtained, however, for the group of desirable O/O homozygotes, the selection approach would result in incorrect genotyping of 31% of individuals. Therefore, a combined approach based on rapid and simple elimination of recessive homozygotes using phenotyping (CIELab photometric measurement) and molecular identification of the EAV-HP insertion in the SLCO1B3 gene in dominant phenotypes, regardless of color intensity affected by laying time/order, and allowing reliable elimination, has proven to be the most effective method to distinguish heterozygotes from the breeding population. The combination of optometric and molecular selection methods then leads to more efficient selection, reduction of overall selection costs. This process led to the stabilization of the breeding population within one generation and the achievement of a pure homozygous line with regard to eggshell color.

Selection of the Optimal Concentration of Nitro Blue Tetrazolium Dye in Polyvinyl Alcohol Film for Diagnostic Radiology

Ensuring the limited exposure of both patients and medical professionals to radiation during examinations is paramount. One effective approach is the utilization of a film dosimeter that is not only efficient but also easy to carry. In this research, we employed polyvinyl alcohol/nitro blue tetrazolium (PVA/NBT) with varying concentrations of NBT dye (ranging from 0.015 to 0.3 g) to identify the most optimal concentration. These films were subjected to low doses of gamma rays (8, 25, 55 and 96 mGy) emitted from 3 Cs-137 sources. XRF analysis confirmed the effectiveness of the preparation method used, and the NBT salt exhibited excellent solubility (R2 = 0.93). The films exhibited an increasing yellow hue as the concentration of NBT dye rose. Following irradiation, they took on a yellowish-brown tint, intensifying with higher gamma doses. PVA/NBT films, when stored in the dark, demonstrated good stability for 30 days post-irradiation. Analysis using ImageJ software unveiled that the relative density of the red color heightened proportionally with the concentration of NBT dye. XRD patterns showcased the clarity of structural rearrangements occurring after irradiation with high NBT concentrations. Two distinct peaks were registered at 2θ = 20.12 and 40.94 °, which shifted to 2θ = 19.74 and 41.30 ° post-gamma irradiation. The CIELab system study and K/S color strength indicated that increasing the NBT dye concentration led to a linear rise in color strength with escalating low gamma doses. Through a comprehensive assessment, it is concluded that PVA/NBT film can be effectively employed as a dosimeter for low gamma doses in diagnostic radiology. HIGHLIGHTS Nine different concentrations of NBT dye were used to prepare PVA/NBT films. The standard dose scale in diagnostic radiology (mGy) was applied in this work. CIELab system parameters showed a linear increase with increasing applied dose. XRD pattern recorded a shifted peak after irradiation from 2θ = 20.12 to 19.74 °. The dose-response was affected by increasing the NBT dye to a certain concentration. GRAPHICAL ABSTRACT

Doping SrSnO3 perovskite with transition metals: Synthesis of double hydroxides, thermal decomposition, and pigment potential

The primary objective of this research is to explore the feasibility of synthesizing phase-pure perovskite SrSnO3 doped with transition metals and to evaluate the potential of these products as high-temperature inorganic pigments. The initial step in preparing perovskite powders with the general formula SrSn0.95M0.05O3-δ (M = Mn, Fe, Co, Ni) involved synthesizing SrSn0.95M0.05(OH)6 followed by its thermal decomposition. The thermal decomposition processes and the reaction pathway for perovskite formation were analyzed using thermal analysis and X-ray diffraction analysis. Single-phase products of beige SrSn0.95Fe0.05O3-δ and brown SrSn0.95Co0.05O3-δ were successfully obtained by calcining the precursors at 1,100 °C. In contrast, brown SrSn0.95Mn0.05O3-δ contained a phase impurity of SnO2 and doping with Ni ions resulted in a phase mixture of SrSnO3 and NiO. The pigment quality of the powders was assessed based on their color parameters, described using the CIE Lab system.

Color Modifications of a Maxillofacial Silicone Elastomer under the Effect of Cigarette Smoke.

Although it is known (from the observations of medical professionals) that cigarette smoke negatively affects maxillofacial prostheses, especially through staining/discoloration, systematic research in this regard is limited. Herein, the color modifications of M511 maxillofacial silicone, unpigmented and pigmented with red or skin tone pigments, covered with mattifiers, or with makeup and mattifiers, and directly exposed to cigarette smoke, were investigated by spectrophotometric measurements in the CIELab and RGB color systems. The changes in color parameters are comparatively discussed, showing that the base silicone material without pigmentation and coating undergoes the most significant modifications. Visible and clinically unacceptable changes occurred after direct exposure to only 20 cigarettes. By coating and application of makeup, the material is more resistant to color changes, which suggests that surface treatments provide increased protection to adsorption of the smoke components. The dynamic water vapor sorption (DVS) measurements indicate a decrease of the sorption capacity in pigmented versus unpigmented elastomers, in line with the changes in color parameters.

Impact of Incorporating Dried Chaga Mushroom (Inonotus obliquus) into Gluten-Free Bread on Its Antioxidant and Sensory Characteristics.

Gluten-free bread is increasingly popular among individuals with celiac disease, and The incorporation of mushroom flour offers a novel method to enhance its nutritional profile, antioxidant content, and sensory properties. This study aimed to evaluate the antioxidant and sensory characteristics of gluten-free bread with varying amounts of chaga mushroom flour (5%, 10%, 15%, 20%). The total contents of polyphenols and flavonoids were measured using a spectrophotometric method. Antioxidant activity was assessed through DPPH and FRAP methods, while textural properties were evaluated using the TPA test. Bread colour was analysed using the CIELab system, and sensory evaluation was performed by a panel of trained consumers. The results showed that gluten-free bread enriched with chaga flour had increased polyphenol and flavonoid content and enhanced antioxidant activity. The highest levels of polyphenols, flavonoids, DPPH, and FRAP activity were found in bread with 20% chaga. The addition of chaga mushroom significantly affected the bread's hardness, cohesiveness, and chewiness. Specifically, 20% chaga flour had the most pronounced effect on hardness and elasticity, while 15% chaga flour had the greatest impact on chewiness and cohesiveness. The bread's colour darkened with higher chaga concentrations. The results of sensory evaluation showed a negative correlation between consumer preferences and bread fortified with chaga mushroom flour. The overall consumer acceptability score indicates that only a small addition of mushroom flour (up to 10%) can be used to bake gluten-free bread.

Pedogenic variables with color indices of rubified Alfisols in the Kakalachinte microwatershed, Karnataka, South India

Soil properties and processes can often be estimated by soil color, which provides valuable information about composition and other properties. We focused on the morphology, particle size distribution, and chemical properties of Alfisols in Kakalachinte microwatershed, Karnataka, India. Soil redness indices were calculated: Buntley's and Westin's rate (BWR), Hurst's rate (HR); Torrent’ rates (TR1 and TR2); Barrón's and Torrent's rates (BTR1 and BTR2), and Viscarra's rate (VR). The Munsell notation was converted to the CIE (Commission Internationale del'Eclairage, CIE) Lab system, Lab model: L*, luminance, a*, redness, and b*, yellowness of moist soil samples. Forty-five soil samples were characterized for texture, soil reaction (pH), electrical conductivity, calcium carbonate content, organic carbon (OC) content, exchangeable cations (sodium, Na; potassium, K; magnesium, Mg; and calcium, Ca), base saturation (BS), and cation exchange capacity (CEC). The pH of the soils ranged from strongly acid (pH of 5.25) to strongly alkaline (pH of 8.73). These soils exhibited low CEC, with a mean of 8.36 cmol(+)/kg and a coefficient of variation of >35%. The BS was found to be >70%, with a dominance of exchangeable Ca (6.93 ± 1.08 cmol(+)/kg). Correlation analysis revealed strong positive relationships between OC and the L* value (r = 0.6**). The correlation results revealed a strong positive correlation of a* value with TR1 (r = 0.54**), significant negative relationship between L* and BTR1 (r = −0.54*), BTR2 (r = −0.525*), and VR (r = −0.53*). Regression between soil OC and the L* value showed R2 of 0.40 and RMSE of 0.01; soil exchangeable K and Mg with the R2 = 0.74; RMSE = 0.12 and the R2 = 0.42; RMSE = 0.11 at p < 0.001. The study highlights the importance of converting Munsell color notation to the CIELab system for understanding the rubification process in relation to soil properties in Alfisols at the microwatershed level.

Effect of different instrumental techniques and clinical experience on shade matching.

Many factors can affect the aesthetics of dental restorations, including the instrumental techniques used in shade matching, and can lead to clinical failure. The aim of this study was to investigate the effectiveness of using the cross-polarization digital photograph technique and intraoral scanners for shade matching, and also evaluate the effect of the level of clinical experience on shade matching success. Color analysis was performed on the maxillary right central incisors of 10 subject models with Vita Easyshade. Intraoral scanning was performed 10 times on each model using TRIOS 3 and color analysis was performed from the same spot. Then cross-polarized and non-polarized photographs of the models were taken with standard settings using a gray reference card. Each shade tab of the Vita System 3D-Master scale was also photographed with two different polarization techniques. Four groups (n = 12), including prosthodontics faculty staff, postgraduate students in prosthodontics, undergraduate students, and dental technicians matched the shade tabs and the model photographs obtained with both techniques on a standardized computer screen. Finally, the color differences between the shade tabs and maxillary central incisors matched by observers from four different groups were recorded using a colorimeter, Classic Color Meter, in accordance with the CIELAB system and CIEDE2000 (ΔE00) values were calculated. The data were compared with the acceptability threshold of 1.80 for ΔE00. The data obtained from the observers were analyzed with IBM SPSS Statistics 26.0 Release Notes program. Independent Samples t-test was used to compare normally distributed data according to binary groups. The level of significance was 0.05. A statistically significant difference was found in the shade matching on photographs taken with different techniques in postgraduate students (p = 0.02). Also, there was a statistically significant difference in success between the groups that made shade matching based on photographs obtained with the non-polarization technique (p = 0.00). The undergraduate students achieved statistically significantly lower results than all other groups (ΔE00 = 5.57±1.07). The kappa value between the intraoral scanner and spectrophotometer results was 0.10, and this value was not statistically significant (p = 0.32). The cross-polarization technique used especially for shade matching is not superior to the non-polarization technique. Academic and clinical experience might be correlated with shade-matching success with the non-polarization technique. The clinical acceptability threshold could not be achieved in the shade matchings made on digital photographs taken with both techniques. Shade matching performed with an intraoral scanner did not yield reliable results.

Physical, colour, and mechanical properties of pearls (citrus caviar) from three finger lime (Citrus australasica) varieties: Implications for economic value, quality grading, and benchmarking

Citrus australasica, the Australian finger lime or caviar lime have garnered interest both in culinary and scientific communities. Despite extensive studies on their metabolomic and volatilomic profiles, research on the physical properties of finger lime pearls, especially their diameter, colour, and mechanical properties, remains limited. Understanding these attributes is crucial for quality assessment, consumer preference, and marketability in the food industry. This study aims to investigate the diameter, visual appearance, and mechanical properties of finger lime pearls from three different varieties (‘Champagne Red’, ‘Emerald’, and ‘Chartreuse’), comparing them with similar foods and assessing their implications for culinary use and market value. Colour properties were analysed using the CIELAB system, and mechanical properties were assessed through texture analysis, focusing on bursting strength and strain. Finger lime pearl diameters ranged between 1.62 and 3.60 mm, aligning with sizes of comparative foods. Colour analysis revealed distinct differences among varieties. Mechanical properties, particularly bursting strength, and strain, varied significantly across varieties, with ‘Champagne Red’ and ‘Chartreuse’ showing higher bursting strengths. These properties suggest different culinary applications and potential for a grading system based on sensory experience. The study highlights the importance of physical and mechanical properties in determining the quality and marketability of finger lime pearls. It introduces a novel framework for assessing these attributes, suggesting that finger lime varieties can be differentiated and graded for culinary use based on pearl diameter, colour, and mechanical properties. This research lays the groundwork for future sensory-based studies and the development of quality grading systems for finger limes.

In situ study of the effect of endogenous and exogenous agents on color stability, hardness, and surface roughness of an elastomer for facial prostheses.

To evaluate in situ the influence of sweat, oil, sunscreen, and disinfectant solution on the color stability, hardness, and roughness of elastomer for facial prostheses. Standardized and intrinsically pigmented specimens remained in contact with human skin from the same person for 30days, considering exposures (n=36 per group), absent of exposition (Control, C); sweat and oiliness contact (SO); sweat and oiliness associated with sunscreen (SOS); 0.12% chlorhexidine digluconate immersion (CD0.12%); and all agents exposed (SOSCD). The main variables were color change (CIELab and National Standard Bureau system, NBS), Shore A hardness, and surface roughness, measured at baseline and 30days. Qualitative analyses were performed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The data were analyzed by Kruskal-Wallis tests (color) and two-way ANOVA (hardness and roughness) with Sidak post-test (α=0.05). CD0.12% (1.54±0.49) and SOSCD (2.10±1.03) had similar effects and caused the smallest color changes, considered mild and noticeable (NBS), respectively. SOS promoted the greatest color change (6.99±1.43, NBS: large) and hardness (17.97±0.56); SOS promoted intermediate roughness (3.48±1.05) between SOSCD (2.25±0.53), and two similar groups: C (4.46±0.95), and CD0.12% (4.39±1.26). The qualitative analysis showed an irregular, dense, dry, and whitish layer on the surface of the specimens exposed to sunscreen, which was reduced when in contact with 0.12% chlorhexidine digluconate. Endogenous and exogenous factors are capable of altering elastomer properties. The 0.12% chlorhexidine digluconate minimized the changes caused by sweat, oil, and sunscreen.

Enhancing the functional properties and performance of paper via cellulose nanocrystals and funori loaded onto ZnO NPs

Purpose This paper aims to investigate the ability of traditional biopolymers, such as funori or the nanoscale form of cellulose nanocrystals, to consolidate fragile paper and preserve it for as long as possible. Design/methodology/approach Degraded papers dating back two centuries were separated into paper samples for consolidation processes. Funori – a marine spleen – was used as a traditional consolidation material and a mixture with ZnO NPs compared with modern materials, such as cellulose nanocrystals. The samples were aged for 25 years, examinations and analyses were performed using scanning electron microscopy and color change was assessed using the CIELAB system, X-ray diffraction and Fourier-transform infrared spectroscopy. Findings According to the results, using traditional materials to consolidate damage, such as funori, after aging resulted in glossiness on the surface, a color change and increased water content and oxidation. Furthermore, samples treated with a mixture of ZnO NPs and funori revealed that the mixture improved the sample properties and increased the degree of crystallization. Cellulose nanocrystals improved the surface, filled gaps, formed bridges between the fibers and acted as a protector from aging effects. Originality/value This paper highlights the ability of nanomaterials to enhance the properties of materials as additives and treat the paper manuscripts from weaknesses.

POTENTIAL OF VIRGIN COCONUT OIL PASTE AS EXTRINSIC DENTAL STAIN REMOVAL

Introduction: Dental stain is a common condition in society, apart from being an aesthetic problem it can be a predisposing factor for periodontal disease.One type of dental stain is extrinsic dental stain. Virgin Coconut Oil contains lauric acid which has the potential to remove extrinsic dental stains through the foaming mechanism. This research is to determine the effectiveness of Virgin Coconut Oil paste on removing extrinsic dental stain through an in vitro study. Material and Methods: Twenty-five post extraction premolars with extrinsic dental stain on buccal area were divided into 5 groups that is : K1/Control(given artificial saliva), K2(given placebo paste), K3(given 50% Virgin Coconut Oil paste), K4(given 75% Coconut Oil Paste) and K5(given 100% Virgin Coconut Oil Paste). Difference colour intensity (ΔE) before and after treatment were observed using Adobe Photoshop CC 2018 in the CieLAB system. Results and Discussion: Data were analyzed using One Way ANOVA and Post-Hoc Multiple Comparison test. One Way ANOVA test showed that there were significant differences within groups (p&lt;0.05). Post-Hoc Multiple Comparison test showed that there were significant differences between each groups, except for K2 and K3 groups also K4 and K5 groups (P&gt;0.05). Conclusion: Virgin Coconut Oil Paste is effective on removing extrinsic dental stain in vitro

Grape Pomace (Vitis vinifera L.) Waste Valorization: Assessing Its Potential as a Sustainable Natural Dye for Textiles Applications

The present study aimed to explore the textile dyeing capability using dyes derived from grape pomace. Extractions were conducted with water at different pH levels and with a water/ethanol solution. Cotton (natural and cationized) and wool were employed in the dyeing process for varying durations (100 and 200 min). The colorimetric and fastness properties, in terms of washing (with hot and cold water) and exposure to natural light, were evaluated. The final color evaluation was performed using ΔE*, a parameter quantifying the magnitude of a color difference by comparing the L*a*b* color coordinates of the CIELAB system of the dyed samples with those of the control. The hues obtained on the fabrics resulted in uniform and earthy colors. However, the cationized cotton substrate showed the highest ΔE* values for all conditions used in obtaining grape pomace extracts, in the range of 33.91 to 37.98. This suggests that the surface treatment enhanced dye uptake, while organic cotton achieved a lighter earthy color. Natural dyeing using grape pomace presents a sustainable, ecological, and non-toxic alternative for textile dyeing, resulting in unique and earthy tones with commercial potential while promoting the sustainable use of natural resources and environmental preservation. The key to achieving sustainable development lies in waste reduction and valorization, along with the adoption of conscious consumption.

Color and surface roughness alterations of bulk-fill resin composites submitted to simulated toothbrushing with whitening dentifrices

Aim: To evaluate the surface roughness and color stability of bulk-fill resin composites after simulated toothbrushing with whitening dentifrices. The radioactive/relative dentin abrasion (RDA) and radioactive/relative enamel abrasion (REA) of dentifrices were also assessed. Methods: Specimens (n=10) of Tetric N Ceram Bulk Fill (TNCB), Filtek One Bulk Fill (FOB) resin composites, and Z100(Control) were prepared using a cylindrical Teflon matrix. Surface roughness (Ra, μm) was assessed by a roughness meter and the color evaluations (ΔEab , ΔE00 , WID ) were performed using a digital spectrophotometer based on the CIELAB system. Three measurements were performed per sample, before and after simulated toothbrushing with 3D Oral-B White Perfection (3DW) and Black is White (BW) dentifrices. The abrasivity (REA and RDA values) of the used dentifrices was also determined by the Hefferren abrasivity test. Results: The Ra values increased significantly in all resin composites after 3DW and BW toothbrushing. The acceptable threshold color varied among resin composites, and TNCB and Z100 presented the highest ΔEab and ΔE00 for BW dentifrice. The 3DW dentifrice was significantly more abrasive than BW dentifrice on enamel and dentin. Conclusions: simulated toothbrushing with tested whitening dentifrices increased the surface roughness at acceptable levels. The Tetric N Ceram Bulk-fill and Z100 composite showed the highest color alteration in BW. 3D White Perfection dentifrice was more abrasive on dentin and enamel than Black is White.

Light-Induced Colour Changes in Wood Surfaces in Indoor Conditions Determined by an Artificial Accelerated Test: Influence of Wood Species and Coating Materials

Stabilising the natural colour of wood species exposed to light in indoor conditions is a challenge that could be better addressed based on a deeper understanding of the occurring phenomena and influencing factors. This paper investigates comparatively the light-induced colour changes for three hardwood species, namely, European maple (Acer pseudoplatanus L.), European ash (Fraxinus excelsior L.) and European walnut (Juglans regia L.), as well as the influence of finishing with three types of clear, colourless waterborne lacquers: acrylic-polyurethane (F1), acrylic (F2) and polyurethane (F3) on their colour stability. Colour measurements in the CIELab system in conjunction with an artificial accelerated ageing test under the action of UV-VIS radiation, simulating natural light passing through window glass, and two types of test samples were employed to highlight the influence and contributions of the wood substrate and of the coating films to the global colour modifications. Coating films applied on 1 mm clear glass slides were employed as a sort of “detachable” finish for this purpose. Direct exposure to UV-VIS light caused visible colour changes for both uncoated and coated wood surfaces, the values of the calculated colour differences (ΔE) after a 72 h exposure being dependant on both the wood species and the coating material. Excepting two situations for walnut, statistically significantly higher colour differences were obtained for the uncoated samples: maple (9.36 units), ash (8.39 units), walnut (6.20 units), compared to the coated ones: maple (4.92–5.71 units), ash (2.25–3.94 units), walnut (4.74–7.70 units). The wood substrates underlying the coating films were found to bring the maximum contribution to the overall colour changes in the clear coated surfaces, while the coating films employed in this research demonstrated a fairly good colour stability to UV-VIS light exposure, with maximum colour changes (∆E) up to only 1.30 units. Overall, the wood species and the type of coating were found as influencing factors in interaction with the light-induced colour changes in wood surfaces in indoor conditions.

Analysis of Skin Color Variation using CIELAB Index: An Empirical Study from Delhi, India

Skin color is a conspicuous trait regulated by complex metabolic processes and its significant diversity among Indian populations is quite remarkable making it an ideal choice for dermatological investigation. To elucidate skin pigment variation with respect to age, we studied 714 healthy individuals (aged 20-70 years) using CIELAB system. Skin reflectance was measured from the volar surface of upper arm using DSM II ColorMeter (Cortex Technology, Hadsund, Denmark) among population of Delhi, India to provide CIELAB color space values, L* (light/dark), a* (red/green), and b* (yellow/blue) followed by statistical analysis to examine the correlation between age and gender on skin on constitutive skin pigmentation. The studied parameters were observed to vary widely {L* (Range: 24.98-51.62, M=38.66, SD=4.41), a* (Range: 4.61-17.16, M=10.18, SD=2.03), and b* (Range: 20.16-34.83, M=28.93, SD=2.30)} across all age groups. ANOVA results suggest a statistically significant effect of age on skin lightness {F(4,709)=124.1332, p&lt;0.001}, redness {F(4,709)=20.0594, p&lt;0.001} and yellowness {F(4,709)=95.1434, p&lt;0.001}. Positive correlation was observed between age and both hue (ho) {r(712)=0.9027, p&lt;0.001} and chroma (C) {r(712)=0.9224, p&lt;0.001}. Significant effects of gender were noticed on skin lightness among all age groups, along with skin redness below the age of 40 years (p&lt;0.001). Notable color differences (∆Ε∗ab) were witnessed among males and females across all age groups in the studied population. The age group 21-30 years was found to have the highest ∆Ε∗ab value (3.5987), followed by 51-60 years (2.98), 31-40 years (2.5579), 61-70 years (2.1837), and 41-50 years (1.6639). We would like to highlight that skin lightness, redness, and yellowness differs significantly with age. Females were observed to be lighter in color as compared to males across all age groups. The findings of the current study would provide better understanding of skin color variation among Indian population.