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Objectives: This study aimed to evaluate the effect of whitening toothpastes on the surface roughness and colour change of CAD-CAM materials. Materials and methods: A total of 96 samples (2 × 10 × 12 mm3) were prepared from Cerasmart (CS) and Celtra Duo blocks. Celtra Duo samples were divided into two groups. One group was fired with glaze paste (CDG) and the other was not treated (CD). All groups were then divided into 4 subgroups (n = 8). The groups were brushed with conventional (Colgate™ Max Fresh), silica (Opalescence™), charcoal (Curaprox™ Black in White) and blue covarine (Signal™ White Now) toothpastes for 30,000 brushing cycles. The initial and final surface roughness values were measured with contact profilometer and a dental spectrophotometer used for obtaining colour values. One sample from each brushed group was analyzed using a scanning electron microscope. Data was analyzed with Kruskal-Wallis and Mann-Whitney tests (p = 0.05). Results: The surface roughness of CS samples brushed with Opalescence™ and Curaprox™ was significantly higher than CD and CDG. Surface roughness change values of CS samples brushed with Curaprox™ were significantly higher than the CD and CDG. Curaprox™ brushed samples showed significant difference in colour change values for all materials. Conclusions: Brushing increases the surface roughness of CAD-CAM ceramic materials. The roughness of resin-based materials is higher than zirconia-reinforced lithium silicates. Silica-contained toothpastes may cause discoloration of nanoceramic and zirconia-reinforced glass ceramic restorations. Clinical relevance: It should be clinically considered that whitening toothpastes may cause roughness in ceramic materials and change the desired color. [ABSTRACT FROM AUTHOR]

Background: Glass ionomer cements with extended setting time and inferior mechanical properties present significant challenges for dentists in clinical practice. Thus, various alterations aimed to enhance their properties. Aim of the study: To study the effect of adding TiO2 and SiO2 nanoparticles on properties of conventional glass ionomer cement. Methods: 2.5 wt% TiO2 and 2.5 wt% SiO2 were added to the glass ionomer cement (GC Gold Label Luting & Lining Cement, Japan). Microhardness, compressive strength, setting time and color changes were evaluated using Vickers hardness tester, Universal testing machine, Gillmore needle apparatus and spectrophotometer, respectively. Results: Data were analyzed using SPSS 18. Mean, SD, and confidence intervals were reported. Normality was checked using Kolmogorov–Smirnov test. The experimental group revealed a higher hardness value than the control group. Meanwhile, Compressive strength results revealed a higher value of the control group than experimental group. Setting time was longer for the experimental group, in the meantime no perceptible color change for the experimental group was recorded. Conclusions: Adding 2.5 wt% TiO2 and 2.5 wt% SiO2 to conventional glass ionomer had a positive effect on microhardness without affecting the perceptible color. [ABSTRACT FROM AUTHOR]

Background and Purpose: This study aimed to evaluate the flexural strength, color change and antimicrobial effect of silver–zeolite nanoparticles (NPs) in acrylic resin materials. Methods: Fifty-six disc-shaped acrylic resin samples were divided into four groups (n = 7) according to concentrations of silver–zeolite NPs (0%, 2%, 4%, 5%). Discs were contaminated with C. albicans and S. mutans. The antimicrobial effect was tested by inoculating contaminated discs on Tryptic soy agar (TSA), Sabouraud Dextrose Agar (SDA), Tryptic soy broth (TSB), and Sabouraud dextrose broth (SDB). Forty rectangular 65 × 10 × 2.5 mm acrylic resin specimens were also classified into four groups (n = 10) according to concentrations of silver–zeolite NPs. For the color change, L, a, and b values of rectangular specimens were examined with a spectrophotometer. A three-point bending test was also performed using a Devotrans device to determine the flexural bond strength of rectangular specimens. Scanning electron microscope analysis (SEM/EDX analysis) was also performed. Results: In this study, the antimicrobial effect increased with the concentration of silver–zeolite NPs added to acrylic resin discs. In our study, adding 2% silver–zeolite NPs was more effective against C. albicans. The antimicrobial effect against S. mutans increased with concentration of silver–zeolite NPs (<0.001). The colonization of C. albicans was significantly reduced by silver–zeolite NPs. A significant increase was observed in the color change as the nanoparticle percentage ratio increased (p < 0.001). The flexural strength values of the groups containing 2% and 4% nanoparticles were found to be clinically acceptable. Conclusions: The study showed that bacterial and fungal colonization is significantly reduced by adding silver–zeolite nanoparticles to acrylic resin discs. Based on its antimicrobial, physical, and mechanical properties, we recommend adding 2% silver–zeolite nanoparticles to the acrylic resin material for optimal results. [ABSTRACT FROM AUTHOR]

Background: Nanocomposite resins have been widely used in modern denture manufacturing. However, their long-term color stability is a concern for both dental professionals and patients. Purpose: to evaluate the effect of different beverages on the color stability of 3D-printed denture base resins modified with zirconium dioxide nanoparticles (ZrO2NPs). Methods: A total of 440 specimens were fabricated and distributed into 11 groups (n = 40/group). The control group of heat polymerized (PMMA) and five groups of two different 3D-printed resins (NextDent and ASIGA) as experimental groups with various concentrations of ZrO2NPs added to the 3D-printed resins (0.5 wt%, 1 wt%, 3 wt%, 5 wt%) in addition to one unmodified group per resin. Specimens per group are sorted into four subgroups (n = 10) according to tested beverages, as follows: coffee, tea, cola, and mineral water. Before immersion, all the specimens were exposed to 5000 thermal cycles. Color changes (ΔE00) were assessed prior (T0) and following immersion for 6 days (T1) and 12 days (T2) using a spectrophotometer. Color difference values were calculated by using CIEDE2000 color difference. Data was analyzed by ANOVA and post hoc Tukey test with a significant level of less than 0.05. Results: Tea produced the highest color change for both NextDent and ASIGA materials, whereas water caused the least color change on PMMA at T2. Increasing the immersion time resulted in more color changes, with tea and coffee showing significant differences. PMMA had considerably less color change than 3D-printed resins. The color change of 3D-printed increased after adding ZrO2NPs. Conclusions: Beverage type and immersion time have an impact on the color stability of unmodified and ZrO2NP-modified denture base resins with significant change after immersion in tea and coffee. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of polishing and denture cleansers on the surface roughness (Ra) of new‐generation denture base materials that are additively, subtractively, and conventionally fabricated, while also assessing their color change after cleansing. Material and Methods: One hundred and fifty disk‐shaped specimens (Ø10 × 2 mm) were prepared from five denture base materials (one subtractively manufactured nanographene‐reinforced prepolymerized polymethylmethacrylate (PMMA) (SM‐GC), one subtractively manufactured prepolymerized PMMA (SM‐PM), two additively manufactured denture base resins (AM‐DT and AM‐ND), and one heat‐polymerized PMMA (CV) (n = 30). The Ra of the specimens was measured before and after conventional laboratory polishing, while color coordinates were measured after polishing. Specimens were then divided into three subgroups based on the denture cleanser: distilled water, 1% sodium hypochlorite (NaOCl), and effervescent tablet (n = 10). The Ra and color coordinates were remeasured after nine cleansing cycles over a period of 20 days. The CIEDE2000 formula was used to calculate the color differences (ΔE00). Two‐way analysis of variance (ANOVA) was used to analyze the Ra values before (n = 30) and after (n = 10) cleansing, while repeated measures ANOVA was used to analyze the Ra of material‐time point pairs within each denture cleanser (n = 10). ΔE00 data after denture cleansing was also analyzed by using two‐way ANOVA (n = 10) (α = 0.05). Results: Before polishing, Ra varied significantly among the materials. SM‐GC and SM‐PM had the lowest and AM‐ND the highest Ra values (P < 0.001). Polishing significantly reduced Ra of all materials (P < 0.001), and after polishing, Ra differences among materials were nonsignificant (P ≥ 0.072). Regardless of the denture cleanser, the Ra of AM‐DT, AM‐ND, and CV was the highest before polishing when different time points were considered (P < 0.001). After cleansing, AM‐ND had the highest Ra of all the materials, regardless of the cleanser (P ≤ 0.017). AM‐DT had higher Ra than SM‐PM when distilled water (P = 0.040) and higher Ra than SM‐GC, SM‐PM, and CV when NaOCl was used (P < 0.001). The type of cleanser significantly influenced the Ra of AM‐DT, AM‐ND, and CV. For AM‐DT, NaOCl led to the highest Ra and the tablet led to the lowest Ra (P ≤ 0.042), while for AM‐ND, distilled water led to the lowest Ra (P ≤ 0.024). For CV, the tablet led to lower Ra than distilled water (P = 0.009). Color change varied among the materials. When distilled water was used, SM‐GC had higher ΔE00 than SM‐PM and AM‐DT (P ≤ 0.034). When NaOCl was used, AM‐ND had higher ΔE00 than SM‐GC, SM‐PM, and AM‐DT, while CV and SM‐GC had higher ΔE00 than SM‐PM and AM‐DT (P ≤ 0.039). Finally, when the tablet was used, AM‐ND and CV had the highest ΔE00, while AM‐DT had lower ΔE00 than SM‐GC (P ≤ 0.015). Conclusions: The tested materials had unacceptable surface roughness (>0.2 μm) before polishing. Roughness decreased significantly after polishing (<0.2 μm). Denture cleansers did not significantly affect the surface roughness of the materials, and roughness remained clinically acceptable after cleansing (<0.2 μm). Considering previously reported color thresholds, AM‐ND and CV had unacceptable color change regardless of the denture cleanser, and the effervescent tablet led to perceptible, but acceptable color change for SM‐GC, SM‐PM, and AM‐DT. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the impact of surface conditioning of titanium, zirconia thickness, and cement type on the final color of zirconia luted to the titanium. Methods: A total of 192 grade 5 titanium specimens with the final dimensions 10 mm × 10 mm × 2 mm were fabricated and subjected to four different surface conditioning including, that is, sandblasting, etching, and anodization. In addition, 192 zirconia specimens with the same dimensions as the titanium specimens but altered thicknesses of 0.7 (n = 96) and 1.0 (n = 96) mm were fabricated using 5Y‐TZP zirconia. Color as expressed by L∗ (lightness), a∗ (red–green axis), and b∗ (blue–yellow axis) of titanium and zirconia specimens as well as the joined titanium–zirconia complex, total assembly (Panavia V5 clear, PC; opaque, PO, each n = 96) were determined under standardized conditions using a spectroradiometer (SpectraScan P‐650). Color differences were calculated using the ΔE00 formula. ANOVA supplemented with post hoc Tukey test for group comparisons was compiled to estimate possible effects of titanium conditioning, zirconia thickness, and type of cement used on the final zirconia color (SPSS Ver. 28; α = 0.05). Results: All investigated factors affected the zirconia color of the total assembly (p < 0.001). Using PO mean values of all groups were still close to baseline colors (ΔE00 between 5.5 and 6.2). When using PC, the final color was significantly altered, irrespective of the other parameters. Specimens luted with PO appeared lighter, less reddish (a∗ was affected predominately by sample thickness), and more bluish, while luting with PC resulted in reduced lightness combined with large shifts along the red and yellow axes. Significance: Color changes of zirconia luted to titanium are primarily affected by the color of the substrate if a translucent cement was used. Vice versa, the application of an opaque cement effectively masked the dark substrate color. Substrate color and choice of cement have to be taken into consideration when performing shade selection. [ABSTRACT FROM AUTHOR]

Aim: The objective of the present study was to investigate the association between the anatomical characteristics of different tooth groups and the diffusion and bleaching effect of hydrogen peroxide (H2O2). Materials and methods: Computed tomography (CT) images from five patients were used to assess the hard tissue thickness and pulp volume (PV) of four tooth groups: lower (mandibular) incisors (LI), upper (maxillary) incisors (UI), canines (C), and premolars (PM). Additionally, 80 bovine tooth disks were divided into four groups (n = 20) to match the thickness of each tooth group studied. All the specimens were exposed to a 35% H2O2 bleaching gel, with 50 pL applied for 45 min during the first, second, and third sessions. Diffusion was evaluated using the peroxidase enzyme method. Color change analyses (AE, AE00, and AWID) were performed after the three application sessions and 7 days after the bleaching treatment using a spectrophotometer. Results: The PM group showed greater thickness and PV, followed by the C, UI, and LI groups (P < 0.001). The LI group had six times greater H2O2 diffusion compared with the PM group (P < 0.001), while the PM group exhibited a PV nine times larger than the LI group. Furthermore, the LI and UI groups achieved color saturation with one fewer session than the C and PM groups. Conclusions: Specific tooth groups have anatomical characteristics that interfere with bleaching treatment in terms of the diffusion and whitening effect of H2O2. Furthermore, the diffusion capacity of H2O2 was inversely proportional to the thickness of the tooth groups. (Int J Esthet Dent 2024;19:268-280) [ABSTRACT FROM AUTHOR]

The study aimed to assess the effects of different surface conditionings on hybrid ceramics (HBC). Hydrofluoric acid was combined with a silane (HFA+S), low-level laser therapy activated Malachite green (LLLT-MG), Ho: YAG laser, and non-thermal plasma (NTP) as surface conditioning methods for HBC. Eighty-four HBC discs were prepared and divided into four groups according to surface conditioning methods. The total number of samples (n = 21) for each group was further split into two for the non-thermocycling and thermocycling subgroups. After surface treatment, all samples were examined to study the effect of color change and surface roughness. The shear bond strength (SBS) test of HBC was performed on thermo-cycled samples. Statistical analysis using ANOVA with Tukey post hoc was performed to observe any significant difference among tested groups, p > 0.05. The HFA+S and Ho: YAG surface-treated samples showed higher SBS than other surface-treated samples due to higher surface roughness. All surface conditioning methods, except NTP, induced noticeable color change, making them less suitable for aesthetical purposes in clinical settings. Overall, surface conditioning methods are critical in affecting shear bond strength through surface roughness and color change. [ABSTRACT FROM AUTHOR]

BACKGROUND: Esthetic orthodontic wires are preferred for their ease to fit in with natural tooth color, but their susceptibility to staining in the oral environment poses a concern. Various Coatings such as Teflon and Epoxy aim to enhance appearance and biocompatibility but may still result in discoloration. Understanding the color stability of these wires under different staining conditions is crucial for a better and enhanced treatment plan. OBJECTIVE: This study intended to assess the color stability of esthetic orthodontic wires under various staining solutions that are often used in daily life. METHOD: Color changes of Teflon and Epoxy-coated esthetic orthodontic wires were meticulously measured at baseline, 7, 14, and 21-day intervals utilizing the precise CIE Lab* color measurement system. A total of thirty-two samples of wires from each brand were prepared (n = 8/group) and immersed in staining solutions (coffee, tea, cola, and saffron). The color change within and between the groups was statistically evaluated (p < 0.05). RESULTS: Significant variations in color stability were observed across different staining solutions. Saffron emerged as the most potent agent, inducing the most pronounced color changes, whereas cola demonstrated the least impact. Furthermore, Epoxy-coated wires consistently exhibited superior color stability compared to their Teflon-coated counterparts across all staining solutions and time intervals. CONCLUSION: This study underlines the significance for orthodontists to consider staining agents' possible effects on orthodontic wires into account when selecting the orthodontic wires. The findings suggest that Epoxy-coated wires hold promise in mitigating discoloration issues during orthodontic therapy. [ABSTRACT FROM AUTHOR]

The objective of this study is to develop cotton fabrics that are capable of reversible color change in response to temperature changes and of providing an opportunity for thermal management. To achieve this objective, chitosan/sodium alginate natural polymer-walled microcapsules with a thermochromic phase change system core, produced by the complex coacervation method were applied to cotton fabrics by impregnation and exhaustion processes. The thermochromic system contains crystal violet lactone (dye), phenolphthalein (developer), and 1-tetradecanol (solvent) and offers a temperature regulation function thanks to 1-tetradecanol which act as a phase change material. The second objective of this study is to examine the performance characteristics of the microcapsules when applied to cotton fabric via the impregnation and exhaustion method. The visual photographs and colorimetric measurement results indicated that the fabrics treated with microcapsules exhibited thermochromic properties with both application methods. The performance of fabric (Fabric 2) treated with microcapsules by the exhaustion method was superior in terms of color change compared to fabric (Fabric 1) treated by the impregnation method. However, the T-history results demonstrated that the thermoregulation effect of Fabric 1 and Fabric 2 was comparable. The results of the air and water permeability tests on the fabrics indicated that both microcapsule application methods resulted in the pores of the fabrics being filled, thereby significantly reducing the permeability values. In addition, the bending rigidity of the fabrics increased with the addition of microcapsules to the fabrics, while the tear strength decreased. As a result, microcapsules can be effectively applied to cotton fabric by both methods. Moreover, the exhaustion method provided superior performance in relation to the affinity effect of the polymers forming the capsule wall structure against cotton cellulose molecules. [ABSTRACT FROM AUTHOR]

This research aimed to develop a 3D-printed pasta formula that, when cooked in various-flavored waters, turns its color into appealing colors that can be used as a cooking indicator. For this aim, a new pasta formula composed of wheat flour (WF), olive oil (EVOO), and red cabbage juice (RCJ) (containing the smart material anthocyanin) was used as print inks. Rheological properties, textural profile analysis, printability and printing accuracy of various pasta dough formulations were first investigated. Subsequently, the color changing, cooking quality, flavor profile (by E-nose) and consumer acceptability of fresh and freeze-dried (FD) 3D-printed pasta cooked in various-flavored waters were evaluated. Results revealed that adding EVOO enhanced the printability and smoothness of the pasta dough. Moreover, the colors of both 3D fresh and FD pasta progressively turned from light blue (before cooking) to uniform red, red/orange, and green after cooking in lemon, orange, and chencun/alkaline waters, respectively. Additionally, cooked fresh and FD pasta showed acceptable and good cooking quality. Furthermore, significant flavor differences among cooked 3D pasta specimens were detected. This study paves the way for developing new 4D pasta products with appealing colors that can be used as a cooking indicator and enhance consumer interaction with pasta during cooking. [ABSTRACT FROM AUTHOR]

Backgrounds: This study aimed to compare the effects of different energy drinks on the surface roughness, weight loss, and color change of various bioactive restorative materials. Methods: Charisma Diamond One, Activa™ BioActive Restorative, Activa™ Presto™ and Equia Forte HT Fil samples were prepared using plastic molds (8 × 2 mm) (n = 10/groups). After polishing, the samples were weighed, their colors were recorded using a spectrophotometer according to the CIEDE2000 system, and their surface roughness was measured using a profilometer. The samples were immersed in Powerade, Burn, Monster and distilled water for 7 days. After immersion, all the measurements were repeated. Statistical analyses were performed using the Wilcoxon signed-rank test and the Mann‒Whitney U test (p < 0.05). Results: All energy drinks roughened the surface of Equia Forte HT Fil (p < 0.05). Powerade and Monster increased the Ra of all materials after 7 days (p < 0.05). Burns affected all materials except the Activa Bioactive (p < 0.05). Significant weight loss was observed in the Equia Forte group after immersion in all the energy drinks, whereas no weight loss was observed in the other groups. According to the color measurements, ΔE00 values were greater in the Burn and Monster groups, except for the Equia Forte HT Fil group (p < 0.05). Conclusion: Energy drinks affected bioactive materials to varying degrees. The glass hybrid material was the most affected, and the bioactive restorative materials based on the resin matrix were the least. [ABSTRACT FROM AUTHOR]

Background: Patients tend to favor the whitening mouthwashes as they are easily applied and affordable. This study aimed to evaluate the effect of hydrogen peroxide versus charcoal-based whitening mouthwashes on color, surface roughness, and color stability of enamel. In the current study, the whitening mouthwashes used have the ability to stop future stains due to their white seal technology. Methods: A total of 21 permanent central incisor teeth extracted for periodontal reasons were used in the present study. Teeth roots were sectioned and crowns were mounted in self-cured acrylic resin blocks. The specimens were randomly divided into three groups (n = 7) according to the tested whitening mouthwash: Control group ‟ DW" (Distilled water), ‟OW" group: Peroxide-based mouthwash (Colgate Optic White) and ‟CP" group: Charcoal-based mouthwash (Colgate® Plax Charcoal). Regarding ‟OW" and ‟CP" groups, the specimens were immersed in 20 ml of the tested mouthwash in each corresponding group for 1 min twice daily (morning and evening) for a total of 12 uninterrupted weeks. Color change was assessed using VITA Easyshade spectrophotometer and surface roughness (Ra) was measured using a white light interferometer. The specimens were stained using black tea solution and color was measured after 24 h of immersion for assessment of color stability. Results: Color change results revealed that both whitening mouthwashes were able to restore color comparable to the control group with no significant difference between them. Regarding surface roughness, the control group showed the highest mean Ra value, followed by ‟OW" group while ‟CP" group showed the lowest mean Ra value. While color stability after staining, the control group showed a significantly higher value than the ‟CP" and ‟OW" groups. Conclusion: Hydrogen peroxide and charcoal-based whitening mouthwashes improve the color of enamel with no adverse effect on the surface roughness. Both whitening mouthwashes were beneficial to maintain the color after staining and prevent future enamel stains. [ABSTRACT FROM AUTHOR]

Purpose: To compare the impact of three different chemical denture cleansers (CDCs) (Corega, chlorhexidine, and hydrogen peroxide) on the surface roughness, microhardness, and color stability of 3D‐printed, computer‐aided design and computer‐aided manufacturing (CAD‐CAM) milled, and heat‐polymerized denture base material (DBM). Materials and Methods: A total of 420 disc‐shaped specimens (10 ± 0.1 × 2 ±0.1 mm) were fabricated using three different construction techniques: three‐dimensional (3D) printing (n = 140), CAD‐CAM milling (n = 140), and heat‐polymerization (n = 140). Sixty specimens (20 of each DBM) were used for baseline (pre‐immersion) measurements (T1) for the tested surface properties (hardness [n = 10/material] and roughness [n = 10/material]). The remaining 360 specimens (n = 120/material) were investigated for surface roughness, microhardness, and color change after immersion for 1 year (T2) in distilled water or CDCs (n = 30/solution and n = 10/test). The data were analyzed using two‐way ANOVA, one‐way ANOVA followed by post‐hoc Tukey's test at a significance level of less than 0.05. Results: Significant differences were observed in the effects of the tested CDCs on the surface roughness, micro‐hardness, and color stability of varying DBM specimens (p < 0.05). Corega showed the highest surface roughness and color change in all DBMs while H2O2 resulted in the lowest microhardness for all DBMs. The lowest changes in all tested properties were seen with distilled water followed by chlorhexidine. A significant effect of type of cleanser, denture base material, and the interaction between the two was seen on all measured properties (p < 0.05). Conclusions: The tested CDCs significantly affected the surface properties of all DBMs but at varying degrees. Corega produced the highest negative effect on roughness and color change while H2O2 dramatically affected the microhardness. Prolonged use of CDCs should be cautiously followed. [ABSTRACT FROM AUTHOR]

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Objectives: This study was aimed to obtain an experimental bleaching agent by adding casein phosphopeptide‐amorphous calcium phosphate (CPP‐ACP) in order to eliminate the mineral loss on the tooth surface after bleaching and to evaluate the bleaching effectiveness. Materials and Methods: In this study, experimental bleaching agents containing 1%, 3% CPP‐ACP and without CPP‐ACP were obtained. Bleaching effectiveness (color change), the effect of bleaching agents on mineral content (energy dispersive x‐ray spectroscopy), surface morphology (scanning electron microscope), and surface hardness of enamel (Vicker's microhardness) before and after bleaching were evaluated. The obtained data were statistically analyzed. Results: When the bleaching levels of the groups were compared, no statistically significant difference was observed between the control and 1% CPP‐ACP groups (p > 0.05) while the addition of 3% CPP‐ACP decreased significantly the effectiveness of the bleaching agent (p < 0.05). When the effects of experimental bleaching agents on surface hardness were examined, while the enamel surface hardness decreased statistically significantly after application in the control group (p < 0.05), no statistically significant change was observed in surface hardness after the application of 1% CPP‐ACP containing bleaching agent (p > 0.05). However, a statistically significant increase was observed in surface hardness after the application of 3% CPP‐ACP containing bleaching agent (p < 0.05). When the Ca and P ratio of the groups were compared, no statistically significant difference was observed between the control and 1% CPP‐ACP groups (p > 0.05), while they increased significantly in 3% CPP‐ACP group (p < 0.05). Conclusions: The addition of 1% CPP‐ACP to the bleaching agent had positive effects on the mineral content and surface hardness of the enamel, and did not negatively affect the whitening effectiveness. Clinical Significance: Adding CPP‐ACP to the bleaching agent at appropriate concentrations can eliminate possible negative effects without compromising the effectiveness of the bleaching agent. [ABSTRACT FROM AUTHOR]

Simple Summary: Entomopathogenic nematodes and their symbiotic bacteria are widely utilized for biological control. However, whether nematode-derived signals influence the immune response of insects remains unexplored. In this study, we provide comprehensive insight into the interactions among symbiotic bacteria, nematode pheromone ascarosides, and the G. mellonella insect host. Our findings reveal that under the induction of Photorhabdus bacteria, ascarosides enhance the host's immunity response. Specifically, they suppress the intensity of body color change and increase the expression of related-immunity gene expression. Additionally, ascarosides reduce the Photorhabdus cell load and delay G. mellonella larval mortality. These results imply that G. mellonella larvae may employ nematode pheromones to enhance insect immunity in the presence of symbiotic bacteria, thereby enhancing the resistance to invasive bacteria. Insects protect themselves through their immune systems. Entomopathogenic nematodes and their bacterial symbionts are widely used for the biocontrol of economically important pests. Ascarosides are pheromones that regulate nematode behaviors, such as aggregation, avoidance, mating, dispersal, and dauer recovery and formation. However, whether ascarosides influence the immune response of insects remains unexplored. In this study, we co-injected ascarosides and symbiotic Photorhabdus luminescens subsp. kayaii H06 bacteria derived from Heterorhabditis bacteriophora H06 into the last instar larvae of Galleria mellonella. We recorded larval mortality and analyzed the expressions of AMPs, ROS/RNS, and LPSs. Our results revealed a process in which ascarosides, acting as enhancers of the symbiotic bacteria, co-induced G. mellonella immunity by significantly increasing oxidative stress responses and secreting AMPs (gallerimycin, gloverin, and cecropin). This led to a reduction in color intensity and the symbiotic bacteria load, ultimately resulting in delayed host mortality compared to either ascarosides or symbiotic bacteria. These findings demonstrate the cross-kingdom regulation of insects and symbiotic bacteria by nematode pheromones. Furthermore, our results suggest that G. mellonella larvae may employ nematode pheromones secreted by IJs to modulate insect immunity during early infection, particularly in the presence of symbiotic bacteria, for enhancing resistance to invasive bacteria in the hemolymph. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to offer an effective nanocomposite for potential use to consolidate and protect deteriorated archaeological pottery. Design/methodology/approach: Three nanocomposites were used in the experimental study. This study used nano Primal AC33, silicon dioxide (SiO2) and montmorillonite (MMT) nanoparticles to protect and consolidate pottery specimens. Pottery specimens were made at 800°C for this investigation. Consolidation materials were applied with a brush. The properties of the treated pottery specimens were assessed using several methods such as digital and scanning electron microscopes, static water contact angle, color alteration, physical properties and compressive strength. Findings: Microscopic examination indicated the ability of the nano Primal AC33/MMT nanocomposites to cover the outer surface well and bind the inner granules. Concerning specimens with code F treated with nano Primal AC33 5%/MMT 3% nanocomposites, it achieved an increase in contact angle (120°), density (1.23 g/cm3) and compressive strength (561 kg/cm2), as well as a decrease in color change (ΔE = 2.62), water absorption (4.45%) and porosity (5.46%). The novelty of the results is due to the characteristics of nano Primal AC33 5%/MMT 3% nanocomposites used in the current study. Originality/value: This study describes the significant results of the analytical methods used for evaluating consolidation materials used in this study. The findings offer useful information for the protection of archaeological pottery. The investigation indicated that nano Primal AC33 5%/MMT 3% nanocomposites gave the best results. Therefore, it is recommended to use this nanocomposite to consolidate archaeological pottery. As a result, the current work provides a promising first step in conserving archaeological pottery for future studies. [ABSTRACT FROM AUTHOR]

The effects of air heat treatment were evaluated on six Korean oak woods: Quercus serrata (Qs), Quercus mongolica (Qm), Quercus acutissima (Qac), Quercus aliena (Qal), Quercus dentata (Qd), and Quercus variabilis (Qv). Color change (ΔE*), weight loss, and density loss were examined using flat-sawn heartwood boards before and after treatment at 160 ℃, 180 ℃, 200 ℃, and 220 ℃ for 2 h. Overall, the ΔE*, weight loss, and density loss increased with temperature. The properties between temperature and species showed distinct differences. A change to a darker color was observed in all species after treatment at 200 ℃. Qm and Qd exhibited the highest and lowest L*, a*, and b* values after treatment at 220 ℃, respectively. The highest ΔE* values were obtained in Qd at 160 ℃, Qs at 180 ℃ and 200 ℃, and Qv at 220 ℃. Qd and Qv exhibited the highest and lowest weight losses at 160 ℃, respectively. Qac and Qal showed the highest and lowest weight losses at 220 ℃, respectively. Qm showed the highest density loss at all temperatures, whereas Qs had the lowest at 160 ℃, and Qac had the lowest values at 180 ℃, 200 ℃, and 220 ℃. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate some characteristics of thermally treated Scots pine (Pinus sylvestris L.) wood specimens such as air-dried density, color change, average surface roughness, and sound absorption capacity. Heat treatment of Scots pine wood was performed at atmospheric pressure at 140, 160, 180, and 200 °C for 2 h. As a result, the air-dried density values of the thermally treated wood decreased as the temperature of the thermal treatment increased. With the increase of thermal treatment temperature, an increase in total color change values was detected on the surfaces of the samples and the color of the samples became darker. The average surface roughness (Ra) value of samples improved due to thermal treatment conditions and the highest value was determined in thermally treated samples at 200 °C as 3.59 µm. At 140 °C the value of maximum sound absorption coefficient was observed to be 0.48 at 2500 Hz and the highest sound transmission loss value, which was 36.7 dB, was measured at 6300 Hz and at 200 °C. [ABSTRACT FROM AUTHOR]

The color-changing effect of tannin, which is a sustainable and environmentally friendly material used in wood preservation, was studied on varnished and un-varnished wood samples. For this purpose, walnut tannin was applied on samples prepared from Scots pine (Pinus sylvestris L.) and walnut (Juglans regia L.) wood in accordance with ISO 3129 (2019) standard with a brush, and then samples were coated with polyurethane varnish and water-based varnish according to ASTM D3023-98 (2017) principles. Color changes were determined according to ASTM D2244-21 (2021). The obtained data indicated that the highest value in the red color tone (a*) was observed in Scots pine+tannin+polyurethane varnish (PU) (14.4) and the lowest was in Scots pine+control+unvarnished (Uvr) (6.5). The highest value for the yellow color tone (b*) was observed in Scots pine+tannin+PU (34.1), the lowest was in walnut+control+Uvr (14.4), and the highest color lightness value (L*) was obtained in Scots pine+control+Uvr (77.0), and the lowest was obtained in walnut+tannin+PU (18.9). The tannin application, which darkened the wood surface, increased the a* and b* values in both wood types while decreasing the color lightness values 60% to 70%. Tannin application caused a noticeable decrease in total color changes in Scots pine. [ABSTRACT FROM AUTHOR]

The aim of this in vitro study was to evaluate the efficiency of diode laser-activated bleaching systems for color change of teeth. 75 extracted teeth were studied in five different bleaching protocols. Group 1: diode laser 445 nm, 320 µm fiber, 0.5W, continuous wave mode, dose 53 J/cm2. Group 2: diode laser 970 nm, 320 µm fiber, 1W, continuous wave mode, dose 106.10 J/cm2. Group 3: diode laser 940 nm, bleaching handpiece, 7W, continuous wave mode, dose 105 J/cm2. Group 4: diode laser 940 nm, 300 µm fiber, 2W, continuous wave mode, dose 47.16 J/cm2. Group 5: bleaching process without laser activation. In groups 1, 2 and 5, teeth were bleached with Perfect Bleach Office + and in groups 3 and 4, LaserWhite20 bleaching gel was used. Tooth color was determined immediately after the bleaching process using a spectrophotometer. Color change data on the CIE L * a * b* system was analyzed statistically by the one-way ANOVA and Tukey's HSD test. All bleaching procedures resulted in a change of color. All laser groups (∆E * ab > 3) have statistically larger ∆E * ab values than the control group (∆E * ab = 0.73) (p < 0.05). The diode laser 445 nm has the largest ∆E * ab value (∆E * ab = 4.65) and results in a significantly higher color difference than all other groups. In terms of color score difference in VITA Shades, all laser-activated groups lead to a lightening effect while the control group leads to only a slight lightening effect. The diode laser 445 nm produced the greatest color difference. Laser-activated bleaching is more effective than conventional bleaching without light activation. The diode laser 445 nm performs best in this in vitro study. [ABSTRACT FROM AUTHOR]

Objective: It is aimed to evaluate the color changes of upper central incisor teeth with different root maturation levels after 15 min of dehydration and rehydration. Materials and Methods: Using the Cvek classification, 60 participants were divided into five groups. A spectrophotometer, equipped with a specially designed jig, was utilized for color measurements. Following isolation, color measurements were conducted at the dehydration process intervals of baseline, 1st, 2nd, 3rd, 5th, 7th, 10th, and 15th minutes. After mouth rinsing, measurements were repeated at the same time intervals during the rehydration process. CIEDE2000 (ΔE00) values and the Whiteness Index (WID) were obtained to compare the color changes between the initial readings and each interval. Friedman and Repeated Measures ANOVA were applied to compare classes by time during the dehydration and rehydration periods, as well as ANOVA and Kruskal‐Wallis tests to compare by classes for each time (p < 0.05). Results: Significant differences emerged in the mean ΔE00 values during dehydration and rehydration periods across all Cvek Classes (p < 0.05). While no statistically significant differences were observed among Classes at different minutes during the rehydration period (p > 0.05), it was particularly noted that the mean ΔE00 values of Classes 2, 3, and 5 at the 2nd minute of dehydration were statistically significantly higher than the mean of Class 1 (p < 0.05). However, when evaluating the starting and ending measurements of both dehydration and rehydration processes, and the overall change in ΔE00 and ΔWID, no significant variations were detected across the Classes (p > 0.05). Conclusions: In teeth that have just erupted and are still undergoing root development, dehydration in the initial minutes results in noticeable color changes. However, the change in ΔE00 and ΔWID of the teeth was found to be similar after the dehydration and rehydration processes. Clinical Significance: According to the Cvek classification, the lower color change in Class 1 teeth within the first 2 min of dehydration and the need for more than 15 min of rehydration for immature teeth with an open apex to return to their initial state after a 15‐min dehydration are crucial for clinicians in terms of color assessment timing. [ABSTRACT FROM AUTHOR]

Tooth color is a major driver of facial esthetics. While permanent changes in tooth shade can be achieved by bleaching and restorations, there is a need for cosmetic products that can cause reversible color changes. This randomized controlled clinical study assessed the effectiveness and safety of a novel color-correcting product (Hismile™ V34 Color Corrector Serum™) versus a placebo (vehicle control lacking the color-change dyes). A single-center, randomized, controlled, examiner-blind, two-group, parallel design, single-use study design was followed. The test products were applied on a cotton bud for 30 s, and then, rinsed off. Tooth shade for maxillary central incisors was measured at baseline, immediately, and at 30 and 60 min, using the Vita Bleachedguide 3D-Master® Shade Guide and the EasyShade Advanced 4.0 spectrophotometer (for determining values of L*a*b*). The subjects (N = 60) had a baseline shade of 1M2 (rank 9) or darker. A single application of the test product resulted in an immediate and significant (p < 0.001) three shade improvement (26.2%) according to the shade guide, and the same significant benefits extended to 30 and 60 min. The placebo product did not alter tooth shade (p = 0.326). These changes were accompanied by significant improvements in the L value (whiteness) up to 30 min, and a reduction in b* (yellowness) for up to 60 min. Two-thirds of subjects using the test product stated in a survey that their teeth appeared both whiter and brighter. No safety issues arose from the use of the test product or vehicle control. These results indicate that using a color corrector can achieve worthwhile changes to tooth shade for up to 60 min. [ABSTRACT FROM AUTHOR]

This article focuses on polyamide materials T1 and B1, and uses two types of fungi to conduct anti mold tests on them. It conducts in-depth exploration and research on the failure mechanism during the co cultivation process!* of fungi and polyamide. Through infrared spectroscopy analysis;, it was; found that mold growth can absorb oxygen from the outside, which can cause the methylene on the polyamide molecular chain to break and react with it to form carbonyl groups, causing changes in the internal structure of the molecule. Through UV spectroscopy and nuclear magnetic resonance analysis, it can be seen that due to the presence of highly reactive methylene structures on the internal molecular chains of polyamide, the color of polyamide and mold will change during the co cultivation process. It will react with the outside world to generate methylene free radicals, further react with oxygen to generate hydrogen peroxide, and then isomerize to generate carbonyl groups. The carbonyl groups then combine with other active groups to produce carbonyl imines. As a result, the conjugated chains on the polyamide molecular chains will increase, and the maximum absorption wavelength will be seen in the visible light region, which is macroscopically manifested as the color change of the polyamide material. Thermogravimetric analysis shows that fungi can obtain nutrients from the surface of polyamide for reproduction, and the surface structure will undergo significant damage and changes. Mechanical performance tests have shown that mold can cause a decrease in the tensile, bending, and impact properties of polyamide materials, and the two types of mold can cause different degrees of attenuation. [ABSTRACT FROM AUTHOR]

Many animals exhibit remarkable colors that are produced by the constructive interference of light reflected from arrays of intracellular guanine crystals. These animals can fine-tune their crystal-based structural colors to communicate with each other, regulate body temperature, and create camouflage. While it is known that these changes in color are caused by changes in the angle of the crystal arrays relative to incident light, the cellular machinery that drives color change is not understood. Here, using a combination of 3D focused ion beam scanning electron microscopy (FIB-SEM), micro-focused X-ray diffraction, superresolution fluorescence light microscopy, and pharmacological perturbations, we characterized the dynamics and 3D cellular reorganization of crystal arrays within zebrafish iridophores during norepinephrine (NE)-induced color change. We found that color change results from a coordinated 20° tilting of the intracellular crystals, which alters both crystal packing and the angle at which impinging light hits the crystals. Importantly, addition of the dynein inhibitor dynapyrazole-a completely blocked this NE-induced red shift by hindering crystal dynamics upon NE addition. FIB-SEM and microtubule organizing center (MTOC) mapping showed that microtubules arise from two MTOCs located near the poles of the iridophore and run parallel to, and in between, individual crystals. This suggests that dynein drives crystal angle change in response to NE by binding to the limiting membrane surrounding individual crystals and walking toward microtubule minus ends. Finally, we found that intracellular cAMP regulates the color change process. Together, our results provide mechanistic insight into the cellular machinery that drives structural color change. [ABSTRACT FROM AUTHOR]

Background: To evaluate the effect of the low-viscosity Icon resin infiltrate application on the color change of white spot enamel lesions (WSLs) over 3-, 6-, and 12-m follow-up periods. Methods: Ninety-six teeth diagnosis with WSLs using the ICDAS scoring system in 49 participants were assessed for their color change using the Icon resin infiltration technique. The Icon kit was applied to WSLs as instructed by the manufacturer. Icon-Etch (15% hydrofluoric acid) was applied to the lesions for 2 min, and then, it was rinsed off with copious amount of water for 30 s. Then, Icon-Dry (99% ethanol) was applied to the etched lesions for 30-s followed by the application of the Icon resin infiltrate that was light cured for 40 s. Color change assessment was performed using Vita Easyshade V spectrophotometer at baseline and immediately after Icon resin infiltration, then at 3-, 6-, and 12-m follow-up periods. Analysis of the data was performed using the test of repeated measure ANOVA and the paired sample t test. Results: There was a statistically significant difference in ∆E between the different follow-up periods at immediate, 3-m, 6-m, and 12-m. The highest mean value was found in the immediate follow-up period, while the lowest mean value was found in 12-m follow-up period. Conclusions: Low-viscosity Icon resin infiltration has the ability for immediate diffusion into the WSLs giving an immediate improvement in the esthetic outcome of the WSLs. However, its long-term outcomes might not be consistent for the color change of the WSLs. [ABSTRACT FROM AUTHOR]

Cellulose detectors, as green sensors, are some of the defensive mechanisms of plants which combat environmental stresses. However, extracted cellulose struggles to fulfil these functionalities due to its rigid physical/chemical properties. In this study, a novel cellulose dual-crosslinked framework (CDCF) is proposed. This comprises a denser temporary physical crosslinking bond (hydrogen bonding) and a looser covalent crosslinking bond (N,N-methylenebisacrylamide), which create deformable spaces between the two crosslinking sites. Abundant pH-sensitive carboxyl groups and ultralight, highly porous structures make CDCF response very sensitive in acid/alkaline vapor environments. Hence, a significant shrinkage of CDCF was observed following exposure to vapors. Moreover, a curcumin-incorporated CDCF exhibited dual shape and color changes when exposed to acid/alkaline vapors, demonstrating great potential for the multi-detection of acid/alkaline vapors. [ABSTRACT FROM AUTHOR]

Papaya (Carica papaya L.) is a typical climacteric fruit with a brief shelf life due to the rapid degradation of quality during post-ripening, necessitating appropriate postharvest management to address this challenge. This study aimed to investigate the characteristics of thyme oil nanoemulsion (TO-NE) coating and utilize its benefits for preserving papaya. This study also investigated the physiological properties and quality changes of papaya storage at 20 ℃ and, in parallel, examined the effects of TO-NE coating to mitigate microbial infection of papaya during storage. The postharvest papaya was soaked in different concentrations (0.1, 0.25, and 0.5 mg/g) of TO-NE for coating. At the same time, the decay loss rate and effective shelf life were also evaluated. This study revealed that polygalacturonase (PG) and pectinesterase (PME) activities were inhibited during the storage of papaya treated with 0.25 mg/g TO-NE coated compared to the control group. This resulted in the preservation of the firmness of papaya fruits, in addition to a higher ascorbic acid content, delayed total soluble solids (TSS) accumulation, and total chlorophyll content (TCC) degradation, with a lagging color change for two days. The respiration rate and ethylene production were suppressed, while the 0.25 mg/g TO-NE coated group at day 14 (ethylene peak) were 63.2 mg CO2 kg−1 h−1 and 7.3 µL kg−1 h−1, lower than control. The 0.25 mg/g TO-NE coating treatment significantly reduced the decay rate for 10 days of storage, preserving their appearance and facilitating ripening. This is a viable option for extending Tainung No.2 papaya shelf life. [ABSTRACT FROM AUTHOR]

Background: Nymphaea (waterlily) is known for its rich colors and role as an important aquatic ornamental plant globally. Nymphaea atrans and some hybrids, including N. 'Feitian 2,' are more appealing due to the gradual color change of their petals at different flower developmental stages. The petals of N. 'Feitian 2' gradually change color from light blue-purple to deep rose-red throughout flowering. The mechanism of the phenomenon remains unclear. Results: In this work, flavonoids in the petals of N. 'Feitian 2' at six flowering stages were examined to identify the influence of flavonoid components on flower color changes. Additionally, six cDNA libraries of N. 'Feitian 2' over two blooming stages were developed, and the transcriptome was sequenced to identify the molecular mechanism governing petal color changes. As a result, 18 flavonoid metabolites were identified, including five anthocyanins and 13 flavonols. Anthocyanin accumulation during flower development is the primary driver of petal color change. A total of 12 differentially expressed genes (DEGs) in the flavonoid biosynthesis pathway were uncovered, and these DEGs were significantly positively correlated with anthocyanin accumulation. Six structural genes were ultimately focused on, as their expression levels varied significantly across different flowering stages. Moreover, 104 differentially expressed transcription factors (TFs) were uncovered, and three MYBs associated with flavonoid biosynthesis were screened. The RT-qPCR results were generally aligned with high-throughput sequencing results. Conclusions: This research offers a foundation to clarify the mechanisms underlying changes in the petal color of waterlilies. [ABSTRACT FROM AUTHOR]

Objectives: Reinforcement of polymethylmethacrylate (PMMA) denture base resins (DBRs) with inorganic fillers with superior properties and accepted aesthetics are favored and still a big dilemma. This study was undertaken to evaluate the color change, flexural strength, and modulus of elasticity of heat-polymerized DBR material modified with silver nanoparticles (AgNPs) and zirconium dioxide nanoparticles (ZNPs). Methods: Sixty acrylic specimens (30/color test, 30/flexural properties) were fabricated and divided according to nanoparticles type and addition into 3 groups (n = 10). Group-I; unmodified specimens, Group-II; modified specimens with 0.5wt% AgNPs (PMMA/AgNPs), and Group-III; modified specimens with 7.5wt% ZNPs (PMMA/ZNPs). Disc-shape (20 × 3 mm) and bar-shape (65 × 10 × 2.5 mm) specimens were fabricated for color and flexural properties, respectively. The spectrophotometer was used for evaluation of the color change (∆E). The flexural strength and elastic modulus evaluation was carried out using a 3-point bending test (5 mm/min). Tukey’s post hoc and one-way ANOVA were used to analyze the data at a significant level P ≤ 0.05. Results: PMMA/AgNPs group exhibited a significant increase in color change when compared with PMMA/ZNPs. PMMA/ZNPs showed significantly the highest flexural strength value when compared with unmodified and PMMA/AgNPs groups (P < 0.001), however, there was an absence of significant differences in terms of flexural strength values between PMMA/AgNPs and unmodified groups (P > 0.05). PMMA/AgNPs insignificantly increased its modulus of elasticity strength (P = 0.09410) while PMMA/ZNPs significantly increased its modulus of elasticity strength (P = 0.00396). Conclusion: The AgNPs and ZNPs addition to PMMA increased the color change and AgNPs change the color of DBRs. The flexural attributes of DBRs have been increased by ZNPs. [ABSTRACT FROM AUTHOR]

An anthracene thiazole based Schiff base L was synthesized and employed for fluorescence switch-on detection of maleic acid in aqueous DMSO. The non-fluorescent L (10–5 M) showed an instantaneous and selective fluorescence enhancement at 506 nm upon interaction with maleic acid (10–5 M). Other potential carboxylic acids (10–5 M), such as malic acid, citric acid, acetic acid, cinnamic acid, tartaric acid, succinic acid, fumaric acid, oxalic acid and malonic acid failed to alter the chromo-fluorogenic properties of L. Probe L can be employed to detect maleic acid down to 2.74 × 10–6 M. The probe L showed good linearity from 2.97 to 6.87 µM. Analytical utility of L was examined by detecting maleic acid in various food additives and drosophila larvae. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the current study was to evaluate the effect of simulated gastric acid on the color and translucency of different indirect restorative materials. Materials and methods: A total of 36 disc-shaped samples were cut by using an isomet saw and divided into four equal groups (n = 9) according to the material type: Group Z: translucent zirconia (Ceramill® Zolid ht.+ preshade, Amann Girrbach, Koblach, Austria); Group E: lithium disilicate (IPS e.max CAD, Ivoclar Vivadent AG, Schaan, Liechtenstein); Group C: resin nanoceramic (Cerasmart, GC, Tokyo, Japan); Group P: polyether ether ketone (PEEK) (Bettin Zirconia Dentale Italy) veneered with indirect high impact polymer composite (HIPC) (breCAM HIPC, Bredent GmbH & Co. KG, Germany). The samples were immersed in simulated gastric acid (HCl, pH 1.2) for 96 hours at 37 °C in an incubator. The color change (ΔE00) and translucency (RTP00) were measured every 9.6 hours (one-year clinical simulation) of immersion in simulated gastric acid. Results: For color change (∆E00) and translucency (RTP00) among the tested materials, there was a highly statistically significant difference (P < 0.001) after every year of follow-up. The color change in both Z and G groups was the lowest after 1 year of acid immersion, followed by that in group H, and the highest change in color was recorded in group P. Conclusion: High translucent zirconia is recommended in patients who are concerned about esthetic, especially with acidic oral environment. [ABSTRACT FROM AUTHOR]

The detection of volatile amines is necessary due to the serious toxicity hazards they pose to human skin, respiratory systems, and nervous systems. However, traditional amines detection methods require bulky equipment, high costs, and complex measurements. Herein, we report a new simple, rapid, convenient, and visual method for the detection of volatile amines based on the gas–solid reactions of tetrachloro-p-benzoquinone (TCBQ) and volatile amines. The gas–solid reactions of TCBQ with a variety of volatile amines showed a visually distinct color in a time-dependent manner. Moreover, TCBQ can be easily fabricated into simple and flexible rapid test strips for detecting and distinguishing n-propylamine from other volatile amines, including ethylamine, n-butyamine, n-pentamine, n-butyamine and dimethylamine, in less than 3 s without any equipment assistance. [ABSTRACT FROM AUTHOR]

Copyright of China Fiber Inspection is the property of China Fiber Inspection 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.)

BACKGROUND: Anthocyanin-based pH-sensing films have been widely fabricated for potential application in monitoring food freshness. However, the color fading of anthocyanins limits their application for the food industry due to their low stability. In addition, the color sensitivity and pH indicator ability of anthocyanin-based films currently available are not satisfied and need to be improved. RESULTS: Chitosan/xanthan gum (CX)-based colorimetric films with addition of purple cabbage anthocyanin (PAN) and different amounts of rosmarinic acid (RA) were fabricated. RA copigmentation in chitosan/xanthan gum--purple cabbage anthocyanin-- rosmarinic acid (CX-P-RA) films significantly improved the stability and pH response sensitivity of PAN, and the combined copigmentation of RA and xanthan gum exhibited an additive effect. The addition of RA significantly improved the tensile strength and elongation at break, thermal stability, antioxidant and antibacterial activities of CX-P-RA films. Moreover, addition of RA enhanced the pH sensitivity and colorimetry of CX-P-RA films, which exhibited a good response to different pH values. CX-P-RA2 film was tested to monitor the freshness of pork. It showed visible color changes during the storage of pork. In addition, the ΔE of CX-P-RA2 film was highly correlated with changes in total volatile basic nitrogen in pork (R² = 0.951). CONCLUSION: These results indicated that CX-P-RA2 film can be used as a pH-sensing indicator with good stability and high sensitivity for real-time monitoring of pork freshness. [ABSTRACT FROM AUTHOR]

Copyright of Selcuk Dental Journal is the property of Selcuk Dental Journal 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.)

Objectives: Assessment of the effect of incorporation of graphene oxide nanoparticles (GONPs), different concentrations into resin composite with different thicknesses on its color modulation. Materials and methods: GONPs were prepared using the chemical reduction method and characterized using a transmission electron microscope and X-ray diffraction. The minimum concentrations of GONPs that provided the most effective antibacterial action (0.05 wt% and 0.2 wt%.) were prepared to be the concentration added to the tested resin composite. Calculations were done to find the required volume of the GONPs solution needed according to the mass of the resin composite. 70 nano-filled resin composite discs were prepared with 10 mm diameter × 3 mm height. 10 resin composite discs were prepared without GONPs incorporation and served as a control (G0). The other 60 resin composite specimens were divided into 2 equal groups (G1& G2) according to the concentration of the loaded nanoparticles in the specimens. Each group was divided into 3 equal subgroups according to the thickness of the resin composite containing GONPs; [T1: GONPs dispersed in the bottom 1 mm of the disc, while the top 2 mm of the disc was of resin composite only. T2: GONPs dispersed only in the bottom 2 mm of the disc and T3: GONPs dispersed in the total thickness of the disc (3 mm)]. ∆E values were calculated using a Vita Easy shade Spectrophotometer. Results: Incorporation of GONPs into resin composite induced significant color change and among all the 6 experimental groups, G1T1 group (of 0.05 wt% concentration GONPs dispersed only in the bottom 1 mm of the disc) showed a non-significant color change. Conclusion: Dispersion of GONPs has a detectable effect on the color change of resin composite. Meanwhile, dispersion in low concentration for only the bottom 1 mm thickness of resin composite has an undetectable effect on its color. [ABSTRACT FROM AUTHOR]

This research primarily delves into a comprehensive investigation concerning the synergistic effects of fly ash (FA) with yellow pigment (YP) and red pigment (RP) in the workability, physical characteristics, and mechanical properties of colored mortars, both pre-and post-exposure to high temperatures. Within the experimental design, FA was employed as a 20% substitute for cement, while YP and RP were systematically incorporated into the cement mixtures at varying concentrations (1%, 3%, and 5% by weight). The specimens underwent controlled exposure to high temperatures, ranging from 300 °C to 800 °C. This study's outcomes unveiled that while the introduction of FA positively influenced mortar workability, including YP and RP adversely impacted spreading diameters (SD), resulting in a discernible reduction in overall workability. Despite these effects, FA emerged as a pivotal factor to enhancing the residual compressive strength (RCS) and residual flexural strength (RFS) of the colored mortars. For instance, after 90 days at 800 °C, the control concrete (R0) exhibited a notable 66.13% decrease in RCS, and the sample solely incorporating FA (R1) demonstrated a reduced reduction of 55.39%. Similarly, mortars with YP additives (R2–R4) and RP additives (R5–R7) showcased RCS reductions within the range of 53.32% to 55.12% and 54.51% to 56.04%, respectively. [ABSTRACT FROM AUTHOR]

The pressure-induced color change in the nitrogen-doped lutetium hydride has triggered extensive discussions about the underlying physics and potential applications. Here, we study the optical response of LuH2±xNy in a broad frequency range at ambient pressure and its evolution with pressure in the visible spectral range. The broad-band optical spectra at ambient pressure reveal a Drude component associated with intra-band electronic transitions and two Lorentz components (L1 and L2) arising from inter-band electronic transitions. The application of pressure causes a spectral weight transfer from L1 to the Drude component, leading to a blue shift of the plasma edge in the reflectivity spectrum alongside a reduction of the high-frequency reflectivity. Our results suggest that the pressure-induced color change in LuH2±xNy is closely related to the transformation between intra- and inter-band electronic transitions, providing new insights into the mechanism of the pressure-induced color change in LuH2±xNy. [ABSTRACT FROM AUTHOR]

The timely and cost-effective identification of the onset of corrosion and its progress would be critical for effectively maintaining structural integrity. Consequently, a series of fundamental experiments were conducted to capture the corrosion process on a steel plate using a new type of plastic optical fiber (POF) sensor. Electrolytic corrosion experiments were performed on a 5 mm thick steel plate immersed in an aqueous solution. The POF sensor installed on the upper side of the plate and directed downward detected the upward progression of the corrosion zone that formed on the underside of the plate. The results showed that the POF sensors could detect the onset of the upward-progressing corrosion front as it passed the 1 and 2 mm marks related to the thickness of the corroded zone. The POF sensors were designed to optically identify corrosion; therefore, the data obtained by these sensors could be processed using a newly developed graphic application software for smartphones and also identified by the naked eye. This method offered an easy and cost-effective solution for verifying the corrosion state of structural components. [ABSTRACT FROM AUTHOR]

In the context of optimizing dental care for patients who are elderly, the purpose of this in vitro study was to evaluate the surface gloss (with a micro-area gloss meter) of, surface roughness (with a compact surface roughness measuring instrument) of, and color change (with a dental colorimeter) in two commercially available injectable resin-based composites (Estelite Universal Flow (EUF) and Beautifil Flow Plus F00 (BFP)) as well as two glass–ionomer cements (GC Fuji II LC CAPSULE (FLC) and GC Fuji IX GP EXTRA CAPSULE (FGP)), before and after dental prophylaxis. After 24 h, the surfaces of each specimen were polished at 2500 rpm with a prophy brush (Mersage Brush, Shofu) and one-step prophylaxis paste (Prophy Paste Pro, Directa): under 100 or 300 gf load, and for 10 or 30 s, 4× cycles of cleaning. After mechanical cleaning, conditions were found for a significant reduction in the gloss level (EUF, BFP, or FLC; p < 0.05) and a significant increase in surface roughness (BFP; 300 gf load, 10 s × four cycles of cleaning). Overall, the longer time or higher prophylaxis load tended to decrease the surface gloss. However, the observed change in surface roughness varied between the restorative materials. There was no color change post-prophylaxis. [ABSTRACT FROM AUTHOR]

To assess the effects of a two‐step temperature method (TTM) on dehydration parameters, color deterioration of dried samples, and specific energy consumption (SEC), spearmint leaves were dried using infrared (IR) undergoing the TTM. Moreover, 14 mathematical models were compared based on the adjusted correlation coefficient, reduced chi‐square, and root mean square error to estimate drying curves. Changes in the color of the dried product at two‐step temperatures of 70to60°C, 60to50°C, and 50to40°C led to decreases of 2.69,.81, and 3.34 compared to fixed temperatures of 70, 60, and 50°C, respectively. On the other hand, the specific energy consumption (SEC) increased by 5.43, 10.92, and 22 MJ.g−1 H2O at 70to60°C, 60to50°C, and 50to40°C compared to 70, 60, and 50°C, respectively. To interpret the results from another point of view, three basic objectives of shortening drying time, reducing energy consumption, and raising the quality of the dried product are achieved in the TTM. For instance, the drying time and energy consumption are reduced at a two‐step temperature of 70to60°C compared to the fixed temperature of 60°C, along with a decrease in the color change compared to the fixed temperature of 70°C. The results indicated that Midilli et al. model resulted in the best fitness in explaining the IR drying behavior of spearmint leaves. Practical applications: During the falling rate period in drying process and especially at higher temperatures and powers, there is a potential for a decrease in the quality of the dried product, and even the risk of thermal runaway due to excessive temperature increase. Certainly, at lower powers and temperatures, the quality of the dried product can be enhanced. However, in this situation, the duration of the process and the energy consumed, which are two crucial factors in the drying process, increase, leading to financial losses for the producer. In the two‐step temperature method (TTM), due to the temperature reduction during the critical period of falling rate, the quality of the dried product improves by considering the processing time and energy consumption. [ABSTRACT FROM AUTHOR]

Simple Summary: The skin of American alligators became lighter when animals were exposed to light colored environments. This change occurred over 2–3 months, and was caused by increased pigmented cells in the dermal layers of the skin. Alligators hatch with bright vertical yellow and black stipes that presumably function as camouflage in emergent vegetation. However, the yellow stripes gradually fade/darken until alligators become a homogenous dark gray/black color as adults. Because alligators live in more temperate climates than other crocodilians, we propose that the loss of yellow stripes might help alligators thermoregulate more efficiently during colder months. We measured the brightness of stripes on wild alligators of a broad spectrum of sizes from three different latitudinal locations within their natural range: northern (South Carolina), central (south Louisiana/southeast Texas), and southern (South Florida). The alligators in South Carolina lost stripes faster as they grew larger, while the alligators in the middle portion of the range became darker at a slower rate, and animals in south Florida lost their stripes at an even slower rate. The loss of stripes at different rates might allow alligators to be more efficient at thermal regulation in the different areas that they inhabit. To assess skin color change in alligators, we maintained animals in differently lighted environments and also measured skin colors in an ontogenetic series of wild animals. Juvenile alligators maintained in black enclosures exhibited a gradual lightening of skin color when shifted to white enclosures, and these observed changes were reversible. A histological examination of the skins of alligators maintained in dark tanks showed that the dermis exhibited a dense layer of pigmented cells, while samples from the same animals in light environments exhibited a more diffuse pigmented layer. As alligators grow, they exhibit an ontogenetic loss of stripes that may aid in crypsis and predation. Hatchlings have intense black and yellow vertical stripes that darken with age; adults are a more homogenous black/gray color. Since alligators live in temperate climates and adults have lower surface area/volume ratios, which can be detrimental for the absorption of radiant energy, the darker color of larger animals may also aid in thermoregulation. Alligators at the northern end of their range, with colder climates, exhibited darker skin tones, and the ontogenetic extinction of stripes occurred at a more accelerated rate compared to animals in southern, warmer regions, supporting the idea that latitude-dependent ontogenetic color shift has a role in thermoregulation. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to find a suitable solution to treat the solidification paper by using hydroxypropyl cellulose (HPC) to improve the mechanical, physical and chemical properties of paper. Design/methodology/approach: The samples have gone several stages, starting with the manufacture of paper from the linen pulp and the same components of the hardened manuscript papers. It was subjected to artificial aging to reach an age comparable to the manuscript age, then it was subjected to natural aging by inoculation it with A. niger. Mechanical cleaning of the leaves was done with soft brushes. The samples have been consolidated by HPC 2%. Digital microscopy, scanning electron microscopy, mechanical properties measurement, color change, Fourier transform infrared and pH measurements were used to assess the effect of HPC on the qualities of leaves. Findings: HPC succussed in strengthening and restoring the natural, chemical and mechanical properties for the solidified leaves. Originality/value: The solidified papers phenomenon constitutes severe suffering for manuscripts and books conservators. The paper consolidation initial stage is one of the most important conservation stages because paper has lost many natural, mechanical and chemical properties. The most important feature of this study is providing a solution to the hardened leaves strengthening problem and restoring their chemical, natural and mechanical properties. [ABSTRACT FROM AUTHOR]

Aim: Papaya fruit was known to have papain enzymes that are able to break down the protein that makes up plaque, where extrinsic stains attach to teeth. The purpose of this study was to determine the effect of papaya fruit extract (Carica papaya L.) on color change of denture elements due to coffee extrinsic stain. Materials and Methods: This study was an experimental laboratory using pre-test and post-test designs. The specimens used in this study were elements of the maxillary central incisor (24 acrylic resin dentures) that have been stained by coffee, totaling 6 specimens per group. The specimens were immersed for 9 days in papaya fruit extract with a concentration of 40%, 60%, 80%, and 100%. Measurement of the specimen color change was done visually before and after soaking papaya extract using Shade Guide Vita 3D Master. Statistical test was carried out with a confidence level of 95%. Results: The results showed that there was a significant color change of the denture elements after soaking papaya extract. The value color dimension changes to be brighter, while the hue and chroma have no significant changes. In the comparison test of four treatment groups with extract concentration (40%, 60%, 80%, and 100%). This study showed that the 60% concentration group had a greater influence on the change in color dimension value. Conclusion: Papaya fruit extract can affect the color change of acrylic resin denture elements that have undergone coffee staining. Immersion of denture elements in papaya fruit extract with a concentration of 60% had a greater effect on color brightness. [ABSTRACT FROM AUTHOR]

Recent advances in wearable devices have enabled noninvasive monitoring for healthcare applications. Smart contact lenses have gained substantial attention for medical diagnosis through the analysis of vital signs in tear fluids. However, previous studies have mostly focused on designs embedded with electronic devices or antennas for wireless transmission, which are power‐intensive and require external receivers around the ocular system. Here, the study reports a power‐free smart contact lens for noninvasive glucose sensing according to the color changes of multiple electrochromic electrodes to achieve direct data transmission without the external wireless system. The device detects various glucose concentrations, from the ordinary range (0.16–0.5 mm) to abnormally high concentrations (0.9 mm). The multi‐electrode design exhibits acceptable accuracy, with a correlation coefficient r = 0.99543 to the controlled sample and allowed low‐glucose detections with concentrations down to 0.05 mm. The device shows good reproducibility, with standard deviations of determined glucose levels of 0.0462 and 0.025 for four continuous cycles and for an interval of several days, respectively. It is believed that the reported smart contact lens has the potential for daily health monitoring by ordinary users without a power supply and external devices. Its simple electronics‐free structure will allow for immediate application to the market with cost‐effective manufacturing. [ABSTRACT FROM AUTHOR]

A significant vegetable in the Cucurbitaceae family, the bitter gourd (Momordica charantia L.) is widely recognized for its beneficial health properties, including anti-diabetic, anti-carcinogenic, anti-inflammatory, anti-ulcer, antiviral activities. With a total of three Brix values (50, 60, and 70) and three different dipping times (10, 20, and 30 h), the goal of the current study was to identify the proper sugar and grape molasses solutions (pekmez) and dipping times for osmotic pre-treatments of bitter gourd samples to make it sweet and widely consumed. In the present study, mathematical modeling of drying processes, moisture content and water activity, total color changes, total phenolic content-antioxidant activity, and carotenoid contents were assessed. As a result of 13 different mathematical modeling tests, "Diffusion Approach", "Logarithmic" and "Midilli et al." models were the best models, giving the highest R2 and lowest X2-RMSE values. There were samples that were dipped at 50 °Brix grape molasses, which decreased below the 10% wet basis (w.b.) limit in the shortest time with 180 min, in a 10 h dipping time. The samples were dipped in 60 °Brix sugar, which fell below the same limit in the shortest time with 135 and 165 min, respectively, at 20 and 30 h dipping times. The highest total phenolic and carotenoid contents were found in 30 h dipping time in 60 °Brix grape molasses with 8296.87 mg/kg and 10 h dipping time in 50 °Brix sugar solutions with 89.22 mg/kg, respectively. While the phenolic content was higher in all samples dipped in grape molasses, the carotenoid content was higher in all samples dipped in sugar, which was one of the most important results of the study. [ABSTRACT FROM AUTHOR]

Color change technology offers unique and challenging opportunities. Thermo-responsive color-changing nanofibers with reversibility have great potential as thermal sensors due to their increased sensitivity and fast response. Herein, polycaprolactone (PCL) nanofibers were produced by adding a leuco-based thermochromic dye with various concentrations (1%, 3%, and 5% wt corresponding to PCL1, PCL3, and PCL5, respectively). The color-changing properties with repetitive heating and cooling were studied, and the effect of dye concentration on the nanofiber properties was determined. The surface properties, dye presence, thermal and mechanical properties were analyzed by SEM–EDS, FTIR, DSC, and tensile tests. Finally, the color change properties were monitored by 1000 heating and cooling cycles between 20 and 40 °C. Thermochromic PCL nanofibers were successfully produced by electrospinning. However, some agglomerates were observed on the nanofibers with increasing dye concentration in SEM images. It was seen that the optimum dye concentration was 3% in terms of the electrospinnability. For PCL5, both presence of carbon, oxygen, nitrogen, and fluorine in EDS spectra, the shifted peaks at 2917 and 2849 cm−1, and the new peaks at 1558, 1517, 1330, 1274, 1213 and 883 cm−1 in FTIR spectra confirmed that dye had been successfully incorporated into the PCL structure. The dye addition caused a decrease in the crystallization degrees, which resulted in lower mechanical properties. PCL5 had the lowest modulus. Color measurements showed that 1% of dyes concentration was not sufficient for the thermochromic property, and the color change was still visually detectable for PCL3 and PCL5 even after 1000 heating and cooling cycles. Color change activation temperature (TA) was confirmed between 30 and 32 °C, and the stability of color change was confirmed for 1000 heating and cooling cycles. After 1000 heating and cooling cycles, the color change was still detectable for PCL3 and PCL5. Consequently, this study showed that reversible thermochromic PCL nanofibers could be promising materials for future sensor applications. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the effect of resin cement shade on the color of different novel ultratranslucent monolithic zirconia and lithium disilicate veneer materials. MATERIALS AND METHODS. For a total of 40 specimens, flat cylindrical discs with a 9-mm diameter and 0.5-mm thickness were created using CAD/CAM technology. The specimens were divided into five groups according to their material (n = 8) (e.max, Prettau, Aidite, Shofu and Dima) using A1 shade. Resin discs with the same diameter and shade as the specimens served as tooth-colored substructures. Three shades (neutral, light and warm) of resin cement try-in pastes (Variolink Esthetic LC) were used as the luting cement material. The color of each material group was measured before and after cementation using the three cement shades, and the CIE L*a* b* coordinates were obtained with a spectrophotometer. Values for the translucency parameter (TP) and color change delta E (E) before (baseline) and after cementation of each specimen were determined. To compare differences among the material groups within each shade of cement and among various shades of cement within each material, the data were analyzed using one-way ANOVA and post hoc testing. RESULTS. Color coordinates L*, a* and b* significantly changed after the application of try-in pastes relative to baseline values, with a noticeable decrease in lightness (L*) (P < .05). A significant color change (ΔE) was observed in all tested materials after cementation, with ΔE values exceeding 3.3 (P < .05). Although TP changed after cementation for most materials tested, these changes were not statistically significant (P > .05). Shofu and Dima ceramics showed the lowest TP values, while Aidite and Prettau showed the highest TP values. For e.max, translucency decreased after cementation with neutral and warm shades, and it significantly increased after cementation with a light shade. CONCLUSION. The shade of cement significantly altered the final color of the ceramic veneer material to a level above the threshold at which the clinical perception of color change occurred (> 3.3). The TP was not influenced by the cement shade. The translucency levels of the novel ultratranslucent multilayer monolithic zirconia ceramics Aidite and Prettau were higher than that of the lithium disilicate e.max material. [ABSTRACT FROM AUTHOR]