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1.
J Environ Sci (China) ; 147: 512-522, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003067

RESUMO

To better understand the migration behavior of plastic fragments in the environment, development of rapid non-destructive methods for in-situ identification and characterization of plastic fragments is necessary. However, most of the studies had focused only on colored plastic fragments, ignoring colorless plastic fragments and the effects of different environmental media (backgrounds), thus underestimating their abundance. To address this issue, the present study used near-infrared spectroscopy to compare the identification of colored and colorless plastic fragments based on partial least squares-discriminant analysis (PLS-DA), extreme gradient boost, support vector machine and random forest classifier. The effects of polymer color, type, thickness, and background on the plastic fragments classification were evaluated. PLS-DA presented the best and most stable outcome, with higher robustness and lower misclassification rate. All models frequently misinterpreted colorless plastic fragments and its background when the fragment thickness was less than 0.1mm. A two-stage modeling method, which first distinguishes the plastic types and then identifies colorless plastic fragments that had been misclassified as background, was proposed. The method presented an accuracy higher than 99% in different backgrounds. In summary, this study developed a novel method for rapid and synchronous identification of colored and colorless plastic fragments under complex environmental backgrounds.


Assuntos
Monitoramento Ambiental , Aprendizado de Máquina , Plásticos , Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Monitoramento Ambiental/métodos , Plásticos/análise , Análise dos Mínimos Quadrados , Análise Discriminante , Cor
2.
Food Chem ; 462: 141027, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39213963

RESUMO

Integrating multiple functionalities into a single entity is highly important, especially when a broad spectrum of application is required. In the present work, we synthesized a novel manganese-based MOF (denoted as UoZ-6) that functions as a cold/hot-adapted and recyclable oxidase nanozyme (Km 0.085 mM) further developed for ratiometric-based colorimetric and color tonality visual-mode detection of nitrite in water and food. Nitrite ions promote the diazotization process of the oxTMB product, resulting in a decay in the absorbance signal at 652 nm and the emergence of a new signal at 461 nm. The dual-absorbance ratiometric platform for nitrite ion detection functions effectively across a wide temperature range (0 °C to 100 °C), offering a linear detection range of 5-45 µM with a detection limit of 0.15 µM using visual-mode. This approach is sensitive, reliable, and selective, making it effective for detecting nitrite ions in processed meat and water.


Assuntos
Colorimetria , Nitritos , Nitritos/análise , Colorimetria/métodos , Estruturas Metalorgânicas/química , Oxirredutases/química , Oxirredutases/metabolismo , Limite de Detecção , Temperatura Baixa , Temperatura Alta , Contaminação de Alimentos/análise , Cor
3.
Plant Mol Biol ; 114(5): 104, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39316226

RESUMO

Fruit color is a key feature of fruit quality, primarily influenced by anthocyanin or carotenoid accumulation or chlorophyll degradation. Adapting the pigment content is crucial to improve the fruit's nutritional and commercial value. Genetic factors along with other environmental components (i.e., light, temperature, nutrition, etc.) regulate fruit coloration. The fruit coloration process is influenced by plant hormones, which also play a vital role in various physiological and biochemical metabolic processes. Additionally, phytohormones play a role in the regulation of a highly conserved transcription factor complex, called MBW (MYB-bHLH-WD40). The MBW complex, which consists of myeloblastosis (MYB), basic helix-loop-helix (bHLH), and WD40 repeat (WDR) proteins, coordinates the expression of downstream structural genes associated with anthocyanin formation. In fruit production, the application of plant hormones may be important for promoting coloration. However, concerns such as improper concentration or application time must be addressed. This article explores the molecular processes underlying pigment formation and how they are influenced by various plant hormones. The ABA, jasmonate, and brassinosteroid increase anthocyanin and carotenoid formation, but ethylene, auxin, cytokinin, and gibberellin have positive as well as negative effects on anthocyanin formation. This article establishes the necessary groundwork for future studies into the molecular mechanisms of plant hormones regulating fruit color, ultimately aiding in their effective and scientific application towards fruit coloration.


Assuntos
Antocianinas , Frutas , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Frutas/genética , Frutas/metabolismo , Antocianinas/metabolismo , Pigmentação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Carotenoides/metabolismo , Cor
4.
Int J Prosthodont ; 37(5): 211-222, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39331577

RESUMO

PURPOSE: To evaluate the influence of abutment material, cement thickness, and crown type on the esthetics of implant supported restorations. MATERIAL AND METHODS: In total, 60 specimens were prepared to represent six abutment groups: Group PA = pink-anodized Ti; Group GA = gold-anodized Ti; Group T = nonanodized Ti; Group H = hybrid (Ti + zirconia); Group P = PEEK (Ti + PEEK); and Group C = composite resin (control). Crown specimens (n = 120) were obtained from Vita Enamic (VE) and Vita Suprinity (VS). Two cement thicknesses (0.1 and 0.2 mm) were used. The color values of crown configura:ons were measured and ΔE00* values were calculated. Statistical analyses included were Shapiro Wilk, three-way ANOVA, and Tukey HSD tests (P ≤ .05). RESULTS: Abutment (P < .001) and crown materials (P = .001) had a significant effect on ΔE00* values, while cement thickness did not. Groups PA and H resulted in significantly lower mean ΔE00* values than other abutments, whereas Group T revealed the highest. Unlike VS, cement thicknesses created a significant difference on the ΔE00* values for VE (P ≤.05). CONCLUSIONS: Pink-anodized Ti or hybrid abutments for VE and pink- or goldanodized Ti for VS seem to be better options, in terms of color change. Cement thickness of 0.1 mm resulted in higher ΔE00* value than 0.2 mm for VE (P ≤ .05).


Assuntos
Cor , Coroas , Dente Suporte , Cimentos Dentários , Prótese Dentária Fixada por Implante , Cimentos Dentários/química , Estética Dentária , Humanos , Zircônio/química , Projeto do Implante Dentário-Pivô , Resinas Compostas/química , Materiais Dentários/química , Pigmentação em Prótese , Planejamento de Prótese Dentária , Teste de Materiais
5.
Int J Prosthodont ; 37(5): 547-558, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39331580

RESUMO

PURPOSE: To compare the color dimensions, color discrepancies (ΔE00), and surface roughness of milled materials before and after application of a bleaching agent. MATERIALS AND METHODS: A total of 10 extracted molars were obtained. Each tooth was cut in transverse sections to create disks (3-mm thick, 10-mm diameter; control group). Disk specimens of eight materials (n = 10 per group) were fabricated: polymethyl methacrylate (PMMA) interim material (PMMA-Telio group), two resin nanoceramics (RNC-Ultimate group and RNC-Cerasmart group), two hybrid ceramics (HC-Shofu group and HC-Enamic group), lithium disilicate (LD-Emax group), zirconia-reinforced glass ceramic (ZGC-Suprinity group), and zirconia (Zr-InCeram group). Color measurements were obtained using a spectrophotometer before and after applying 35% hydrogen peroxide-based bleaching agent. Pre- and postbleaching surface roughness (Sa) analyses were completed using a profilometer. RESULTS: Significant L*, a*, b*, and ΔE00 value differences were found (P < .05). Color discrepancies (ΔE00) ranged from 0.30 ± 0.14 to 4.82 ± 0.10. The highest color discrepancies were measured on the PMMA-Telio group, while the lowest color discrepancies were computed for ZGC-Suprinity, RNCUltimate, and RNC-Cerasmart. Significant surface roughness differences were found (P < .05). The largest increase of surface roughness values between the pre- and postbleaching measurements was obtained in the PMMA-Telio group with a mean ΔSa value of 4.73 ± 3.02, while the largest decrease of surface roughness values between the pre- and postbleaching measurements was obtained in the Zr-InCeram group with a mean ΔSa value of -1.58 ± 0.10. CONCLUSIONS: The milled materials showed significant pre- and postbleaching color and surface roughness discrepancies.


Assuntos
Cerâmica , Cor , Materiais Dentários , Peróxido de Hidrogênio , Propriedades de Superfície , Zircônio , Materiais Dentários/química , Cerâmica/química , Zircônio/química , Humanos , Porcelana Dentária/química , Teste de Materiais , Clareadores Dentários/química , Espectrofotometria , Polimetil Metacrilato/química , Restauração Dentária Permanente
6.
Molecules ; 29(18)2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39339387

RESUMO

The current study proceeded to reduce the environmental hazards spreading worldwide due to synthetic dyes. To overcome these problems, eco-friendly natural dyes are introduced as alternative sources of synthetic dyes. The present study was focused on exploring the bio-colorant of the aqueous and acidic extract of the bark of Melia azedarach L. for the dyeing of both silk and cotton samples. The results of the extraction medium specified that the aqueous extract gave maximum colorant solubility and upon fabric dyeing produced higher color strength in contrast to the acidic medium. The optimization experimentation data showed that excellent color strength of silk fabric was found at 45 min dyeing time duration, in 35:1 mL dye extract, and using 2% salt (NaCl) as an exhausting agent, whereas cotton fabric showed the maximum K/S value at 60 min dyeing time, in a 45:1 mL liquor ratio, and with the use of 2% salt. Bio-mordants produce different shades on both fabrics. Bio-mordanting experiments on silk revealed that pre-mordanting with 2% turmeric and 3% pomegranate, and post-mordanting using 3% turmeric and 2% pomegranate produced a darker shade. In the case of cotton, the pre-mordanted samples with 2% turmeric and 3% pomegranate and the post-mordanted samples with 4% turmeric and 4% pomegranate gave the highest color strengths. All the mordanted samples gave excellent fastness ratings. Overall, it has been found that Bakain bark proved to be an excellent source of tannin. The result of this study showed that it could be a cost-effective and eco-friendly dye source for textile progress.


Assuntos
Corantes , Casca de Planta , Extratos Vegetais , Têxteis , Corantes/química , Casca de Planta/química , Extratos Vegetais/química , Têxteis/análise , Celulose/química , Cor , Fibra de Algodão/análise
7.
Dent Mater J ; 43(5): 746-754, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39261021

RESUMO

This study evaluates the 5-year clinical performance of Class II restorations performed with different bulk-fill restorative materials. In the study, Class II restorations performed with Tetric Bulk-Fill (TBF), Filtek Bulk-Fill (FBF), and Equia Forte Fil (EF) were evaluated. One hundred-nineteen restorations were included in the study. Restorations were assessed during the 6th month, 1st, 2nd, and 5th year. Cochran Q, Pearson chi-square, and Fisher-Freeman-Halton tests were used for statistical analysis. In the 5th year, significant differences were observed in terms of retention, color match, marginal adaptation, marginal discoloration, surface texture, and anatomical form in all materials. There was a significant difference between EF and bulk-fill composites only in terms of retention and anatomical form. EF was significantly less successful than bulk-fill composites with regard to retention and anatomical form, but bulk-fill composites have shown similar clinical performance. EF cannot be an alternative to bulk-fill composites for Class II restorations.


Assuntos
Resinas Compostas , Adaptação Marginal Dentária , Restauração Dentária Permanente , Propriedades de Superfície , Resinas Compostas/química , Humanos , Seguimentos , Masculino , Feminino , Adulto , Materiais Dentários/química , Pessoa de Meia-Idade , Cor , Teste de Materiais
8.
Sci Rep ; 14(1): 20733, 2024 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237638

RESUMO

This study improves the Logistic chaotic system and combines it with the hyperchaotic Chen system to create a dual chaotic system. The algorithm encrypts images in three stages. In the first stage, a plaintext-related key generation scheme is designed to generate the parameters and initial values of the dual chaotic system. In the second stage, the chaotic sequences generated by the dual chaotic system are used for dynamic DNA encoding and computation. In the third stage, the chaotic sequences generated by the improved Logistic chaotic system are used to perform row-column permutations, completing the scrambling. The security analysis of the encrypted images shows that the algorithm described in this paper is robust and secure, capable of resisting most known attacks. The algorithm is fast in encryption, provides high-quality image reconstruction, and is suitable for scenarios with high comprehensive performance and image quality requirements.


Assuntos
Algoritmos , Cor , Segurança Computacional , DNA , Processamento de Imagem Assistida por Computador , DNA/genética , Processamento de Imagem Assistida por Computador/métodos , Dinâmica não Linear
9.
Anal Chem ; 96(37): 14809-14818, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39231502

RESUMO

Cell-cell interactions are essential for the proper functioning of multicellular organisms. For example, T cells interact with antigen-presenting cells (APCs) through specific T-cell receptor (TCR)-antigen interactions during an immune response. Fluorescence-activated droplet sorting (FADS) is a high-throughput technique for efficiently screening cellular interaction events. Unfortunately, current droplet sorting instruments have significant limitations, most notably related to analytical throughput and complex operation. In contrast, commercial fluorescence-activated cell sorters offer superior speed, sensitivity, and multiplexing capabilities, although their use as droplet sorters is poorly defined and underutilized. Herein, we present a universally applicable and simple-to-implement workflow for generating double emulsions and performing multicolor cell sorting using a commercial FACS instrument. This workflow achieves a double emulsion detection rate exceeding 90%, enabling multicellular encapsulation and high-throughput immune cell activation sorting for the first time. We anticipate that the presented droplet sorting strategy will benefit cell biology laboratories by providing access to an advanced microfluidic toolbox with minimal effort and cost investment.


Assuntos
Emulsões , Citometria de Fluxo , Citometria de Fluxo/métodos , Emulsões/química , Humanos , Corantes Fluorescentes/química , Linfócitos T/citologia , Cor , Separação Celular/métodos , Animais
10.
Commun Biol ; 7(1): 1139, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271907

RESUMO

With recent advances in multi-color super-resolution light microscopy, it is possible to simultaneously visualize multiple subunits within biological structures at nanometer resolution. To optimally evaluate and interpret spatial proximity of stainings on such an image, colocalization analysis tools have to be able to integrate prior knowledge on the local geometry of the recorded biological complex. We present MultiMatch to analyze the abundance and location of chain-like particle arrangements in multi-color microscopy based on multi-marginal optimal unbalanced transport methodology. Our object-based colocalization model statistically addresses the effect of incomplete labeling efficiencies enabling inference on existent, but not fully observable particle chains. We showcase that MultiMatch is able to consistently recover existing chain structures in three-color STED images of DNA origami nanorulers and outperforms geometry-uninformed triplet colocalization methods in this task. MultiMatch generalizes to an arbitrary number of color channels and is provided as a user-friendly Python package comprising colocalization visualizations.


Assuntos
Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência/métodos , Cor , Algoritmos , DNA/química , DNA/metabolismo , Microscopia/métodos , Software
11.
Brain Behav ; 14(9): e70020, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39295080

RESUMO

INTRODUCTION: Occupational hazards are partly caused by the physical factors of the work environment, among which are ambient color and brightness, which can interfere with cognitive performance. Especially in modern work environments, performance relies heavily on cognitive functions such as attention, and an important factor in disrupting sustained attention is mind wandering (MW). This study aimed to investigate the effects of white and blue colors with two brightness levels on sustained attention and brain electrophysiology. METHODS: A total of 20 participants were exposed to 4 different conditions (white and blue as color and 300 and 800 lx as the brightness level) in separate blocks in a virtual reality environment in which a continuous performance test (CPT) was performed. RESULTS: The high brightness blue condition induced significant changes in sustained attention. MW network analysis showed a significant decrease in delta frequency band in the blue color condition with high brightness and beta decrease in the blue color condition with low brightness, whereas the activity of MW network increased when exposed to the white color condition. CONCLUSION: High-brightness blue light resulted in better sustained attention and decreased activity of MW-related neural regions. It is thus recommended that these results be taken into consideration in the interior design of educational settings and cars among other environments that require a high level and maintenance of cognitive functions, especially sustained attention.


Assuntos
Atenção , Humanos , Atenção/fisiologia , Masculino , Adulto Jovem , Feminino , Adulto , Percepção de Cores/fisiologia , Eletroencefalografia , Encéfalo/fisiologia , Cor , Realidade Virtual
12.
Meat Sci ; 218: 109644, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39241667

RESUMO

Protein grass hay (PGH) was used as a new feed source for lambs to study its effect on fattening performance and meat quality. Fifty-six male lambs were allotted to four experimental groups and fed for eight weeks either alfalfa hay (AH)-based diet (control) or diets in which AH was replaced with 33 %, 66 %, or 99 % PGH. The inclusion of PGH did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio, or carcass weight. Moreover, substituting AH with PGH at any level did not influence the ruminal fermentation or serum biochemical parameters, meat color, water holding capacity, shear force, or amino acid profile. However, relative liver weight was increased with 66 % substitutions. Furthermore, replacing 99 % AH with PGH decreased the meat's pH at 24 h. Higher levels of C18:3n-3, C20:5n-3, and total n-3 PUFA and a lower ratio of n-6: n-3 PUFA were also observed in meat from lambs fed PGH at 99 %. These findings suggest that PGH could be incorporated into the lamb's diet up to 99 % without compromising fattening performance and body health while improving their meat n-3 PUFA deposition.


Assuntos
Ração Animal , Dieta , Poaceae , Carne Vermelha , Carneiro Doméstico , Animais , Masculino , Ração Animal/análise , Dieta/veterinária , Carne Vermelha/análise , Proteínas Alimentares/análise , Fenômenos Fisiológicos da Nutrição Animal , Rúmen/metabolismo , Medicago sativa , Concentração de Íons de Hidrogênio , Ácidos Graxos Ômega-3/análise , Fígado/metabolismo , Fígado/química , Aminoácidos/análise , Fermentação , Cor , Músculo Esquelético/química
13.
Compr Rev Food Sci Food Saf ; 23(5): e70010, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39267185

RESUMO

Withering and spreading, though slightly differing in their parameters, share the same aim of moisture reduction in tea leaves, and they have a strong impact on the physical and chemical properties of tea. Even though researchers tend to pay close attention to the characteristic crafts of different teas, increasing investigations begin to focus on the withering process due to its profound effects on the composition and content of quality-related compounds. This review provides an overview of tea withering process to address questions comprehensively during withering. Hence, it is expected in this review to figure out factors that affect withering results, the way withering influences the physical and chemical properties of withered leaves and tea quality, and intelligent technologies and devices targeted at withering processes to promote the modernization of the tea industry. Herein, several key withering parameters, including duration, temperature, humidity, light irradiation, airflow, and more, are tailored to different tea types, demanding further exploration of advanced withering devices and real-time monitoring systems. The development of real-time monitoring technology enables objective and real-time adjustment of withering status in order to optimize withering results. Tea quality, including taste, aroma, and color quality, is first shaped during withering due to the change of composition and content of quality-related metabolites through (non)enzymatic reactions, which are easily influenced by the factors above. A thorough understanding of withering is key to improving tea quality effectively and scientifically.


Assuntos
Camellia sinensis , Manipulação de Alimentos , Folhas de Planta , Chá , Chá/química , Manipulação de Alimentos/métodos , Camellia sinensis/química , Folhas de Planta/química , Paladar , Cor
14.
BMC Oral Health ; 24(1): 1124, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327573

RESUMO

BACKGROUND: There is a lack of studies comparing the dimensional accuracy and color stability of denture base resins made using computer-aided design and computer-aided manufacturing (CAD-CAM) milling, 3-dimensional (3D) printing, and conventional denture processing techniques. This makes it challenging to determine the best method to fabricate complete dentures. The objective of this in vitro investigation was to assess and contrast the color stability and dimensional accuracy of denture base resins that were 3D printed and CAD-CAM milled, both before and after aging by thermocycling using digital surface matching technology and a benchtop laser scanner without using a spray, to optimize adaptation of the denture base and cast to minimize any imperfections and to evaluate the impact of the denture cleansing solution on the stability of color. METHODS: Evaluation of the dimensional accuracy (n = 27) was completed on a sectional maxillary stone cast using a digital 3D-surface matching software before and after 5000 thermocycles. A spectrophotometer was used to measure the color change (△E00) of all disc specimens (N = 54) before and after 500 thermocycles and immersion in denture cleansing solution for 30 cycles (3 min each) daily for 6 days. The Kruskal Wallis test, Dunn's post hoc test, Tukey's test with Bonferroni adjustment, one sample t test and independent t test were used to statistically analyze the data (α < 0.05). RESULTS: Thermocycling decreased the dimensional accuracy of the heat polymerized group at all 5 locations and the 3D-printed group at locations 1, 3 and 5 (P > .05), while it had no significant difference on the CAD-CAM milled group at all locations (P < .05). The color change (△E00) was lowest in the CAD-CAM milled group, moderate in the heat-polymerized group and highest in the 3D-printed group. After immersion in denture cleanser, the color change (△E00) was significantly higher in the 3 groups compared with after thermocycling (P > .001). CONCLUSIONS: CAD-CAM milled resins had the highest dimensional accuracy and the best color stability, conventional heat polymerized acrylic resins showed moderate change in dimensional accuracy and color stability, while the 3D- printed resin had the lowest dimensional accuracy and color stability after aging by thermocycling.


Assuntos
Cor , Desenho Assistido por Computador , Bases de Dentadura , Impressão Tridimensional , Técnicas In Vitro , Planejamento de Dentadura , Fatores de Tempo , Espectrofotometria , Humanos , Propriedades de Superfície , Resinas Acrílicas/química , Teste de Materiais , Higienizadores de Dentadura/química
16.
Am J Dent ; 37(5): 247-254, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39321105

RESUMO

PURPOSE: To evaluate the surface roughness and color stability of a single-shade composite resin after thermal cycling with different finishing and polishing systems. METHODS: A total of 91 specimens were prepared with standard molds using a single-shade resin composite Omnichroma. The specimens were randomly separated into seven groups: Control (Mylar strip only), grit (600 grit SiC abrasive paper), OneGloss, Clearfil Twist Dia, Sof-Lex Diamond Polishing System, EVE Diacomp Plus Twist, and OptiDisc. The top surface of each specimen was polished per the manufacturers' directions. After initial measurements, 10,000 and 50,000 thermal cycles were performed. After each thermal cycling, the measurements were retaken. A generalized linear model analysis was used to compare the values, and multiple comparisons were performed with the Bonferroni correction. RESULTS: Different finishing and polishing systems and thermal cycling significantly affected the surface roughness and color change of the single-shade composite resin (P< 0.001). The smoothest surfaces were obtained with the Sof-Lex Diamond Polishing System, while the group polished with Clearfil Twist Dia showed the least color change. CLINICAL SIGNIFICANCE: The surface roughness of the single-shade resin composite exhibited acceptable values for all polishing systems tested. The color change values of the single-shade resin composite were found to be above the acceptable value for all polishing systems, but the two-step spiral polishing systems performed better in terms of color stability.


Assuntos
Cor , Resinas Compostas , Polimento Dentário , Teste de Materiais , Propriedades de Superfície , Polimento Dentário/métodos , Resinas Compostas/química
17.
Braz Dent J ; 35: e245910, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39320002

RESUMO

This study aimed to evaluate the masking ability of different resin composite (RC) layering techniques over discolored substrates. Layering strategies were tested (n=10), using different RCs: flowable opaque, white dentin, A1 dentin, A1 body, and A1 enamel (Filtek Z350XT; 3M ESPE). Bilayer and trilayer RC combinations resulted in final thicknesses of 1 mm, 1.5 mm, and 2 mm. Substrates tested were: A1 (reference), A3, A4, B3, C2, and C4 (Filtek Z350XT Dentin; 3M ESPE). Color differences (∆E00) were measured for the RC layers over discolored substrates with the CIEDE2000 formula. The results were compared statistically (One-way ANOVA) and descriptively (acceptability=1.77 and perceptibility=0.81 thresholds). The layering strategy influenced the ∆E00 of RCs over all substrates (P<0.001). The 1 mm bilayer group combining 0.5 mm of dentin and 0.5 mm of enamel led to ∆E00 below AT for substrates A3 and B3; the 1.5 mm bilayer group combining A1 dentin (1 mm) and enamel (0.5 mm) provided ∆E00 below AT for substrates A3, A4, and C2 and ∆E00 below PT for B3; for substrate C4, the 2 mm trilayer group combining flowable opaque (0.2 mm), A1 dentin (1.3 mm) and enamel (0.5 mm) provided ∆E00 below PT, and the 1.5 mm trilayer groups (flowable opaque + 0.8 mm dentin or body + enamel) led to ∆E00 below AT. Resin Composites were effective in masking discolored substrates. The most adequate layering strategy depended on substrate shade.


Assuntos
Resinas Compostas , Resinas Compostas/química , Cor , Humanos , Teste de Materiais , Propriedades de Superfície , Esmalte Dentário , Dentina
18.
Zhongguo Zhong Yao Za Zhi ; 49(16): 4437-4449, 2024 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-39307780

RESUMO

Traditional Chinese medicine(TCM) placebos are simulated preparations for specific objects and the color simulation in the development of TCM placebos is both crucial and challenging. Traditionally, the prescription screening and pattern exploration process involves extensive experimentation, which is both time-consuming and labor-intensive. Therefore, accurate prediction of color simulation prescriptions holds the key to the development of TCM placebos. In this study, we efficiently and precisely predict the color simulation prescriptions of placebos using an image-based approach combined with Matlab software. Firstly, images of TCM placebo solutions are captured, and 13 chromaticity space values such as the L* a* b*, RGB, HSV, and CMYK values are extracted using Photoshop software. Correlation analysis and normalization are then performed on these extracted values to construct a 13×9×3 back propagation(BP) neural network model. Subsequently, the whale optimization algorithm(WOA) is employed to optimize the initial weights and thresholds of the BP neural network. Finally, the optimized WOA-BP neural network is validated using three representative instances. The training and prediction results indicate that, compared to the BP neural network, the WOA-BP neural network demonstrates superior performance in predicting the pigment ratios of placebos. The correlation coefficients for training, validation,testing, and the overall dataset are 0. 95, 0. 87, 0. 95, and 0. 95, respectively, approaching unity. Furthermore, all error values are reduced, with the maximum reduction reaching 99. 83%. The color difference(ΔE) values for the three validation instances are all less than 3, further confirming the accuracy and practicality of the WOA-BP neural network approach.


Assuntos
Algoritmos , Cor , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Redes Neurais de Computação , Medicamentos de Ervas Chinesas/química , Placebos , Animais
19.
Planta ; 260(4): 97, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39278990

RESUMO

MAIN CONCLUSION: Microscopic analyses and chemical profiling demonstrate that the white rind phenotype in melon fruit is associated with the accumulation of n-alkanes, fatty alcohols, aldehydes and wax esters. Serving as an indicator of quality, the rind (or external) color of fruit directly affects consumer choice. A fruit's color is influenced by factors such as the levels of pigments and deposited epicuticular waxes. The latter produces a white-grayish coating often referred to as "wax bloom". Previous reports have suggested that some melon (Cucumis melo L.) accessions may produce wax blooms, where a dominant white rind color trait was genetically mapped to a major locus on chromosome 7 and suggested to be inherited as a single gene named Wi. We here provide the first direct evidence of the contribution of epicuticular waxes to the dominant white rind trait in melon fruit. Our light and electron microscopy and gas chromatography-mass spectrometry (GC-MS) comparative analysis of melon accessions with white or green rinds reveals that the rind of melon fruit is rich in epicuticular waxes. These waxes are composed of various biochemical classes, including fatty acids, fatty alcohols, aldehydes, fatty amides, n-alkanes, tocopherols, triterpenoids, and wax esters. We show that the dominant white rind phenotype in melon fruit is associated with increased accumulation of n-alkanes, fatty alcohols, aldehydes and wax esters, which are linked with the deposition of crystal-like wax platelets on their surfaces. Together, this study broadens the understanding of natural variation in an important quality trait of melon fruit and promotes the future identification of the causative gene for the dominant white rind trait.


Assuntos
Frutas , Ceras , Cor , Cucumis melo/genética , Cucumis melo/metabolismo , Cucurbitaceae/genética , Cucurbitaceae/metabolismo , Frutas/genética , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Fenótipo , Pigmentação/genética , Ceras/metabolismo , Ceras/química
20.
BMC Oral Health ; 24(1): 1104, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289670

RESUMO

BACKGROUND: The effect of an immune-boosting beverage (SAM) containing Sambucus Nigra, an energy beverage (ENE), an in-office bleaching (BLE) agent with 25% hydrogen peroxide superior, glazing (GLA) or polishing (POL) methods, and professional dental prophylaxis (PDP) on the color of CAD-CAM restorative materials is unknown. METHODS: In total 210 specimens were prepared, consisting of CAD-CAM feldspathic (FC), zirconia-reinforced lithium disilicate ceramic (ZLS) and hybrid ceramic (HC). The ceramic specimens were divided according to the polishing methods of glazing (GLA) and mechanical polishing (POL). All materials were divided into two groups: with and without BLE. A 25% hydrogen peroxide superior (HPS) gel was used for BLE. After the baseline (BAS) measurement, the specimens were immersed in 3 different beverages (distilled water (DIS), SAM, ENE). After 28 days, a fine-grained (RDA 7) prophylaxis paste was applied. Statistical analysis of ∆E00 color difference values was performed by 3-way ANOVA and Bonferroni test (α = 0.05). RESULTS: The effect of all other actions except material-BLE-beverage on color for BAS-Day 28 was statistically different (p < 0.05). The effect of material, material-BLE, beverage on color for Day 28-PDP was statistically different (p < 0.05). After 28 days, the lowest color change was found in FC-GLA and HC immersed in DIS (p = 0.0001) and the highest in FC-POL immersed in ENE (p = 0.0002). PDP was efficient in color recovery in HC immersed to DIS, ENE and SAM (p = 0.0010). For FC, HC and ZLS, BLE caused a higher color change (p < 0.0001). Regardless of the material, the highest color change for BLE-beverage was found in BLE-treated specimens immersed in ENE (p = 0.0496) and the lowest color change was found in non-BLE-treated specimens immersed in SAM (p = 0.0074). CONCLUSIONS: In materials pre-exposed to 25% HPS, the effect of PDP on color recovery was lower than in unexposed materials. After 28 days, mechanical polishing produced higher color change in FC than glazing, however, in ZLS effects of glazing and mechanical polishing on color were similar. For material/polishing method, HC was the most effective. ENE caused higher color change than DIS and SAM. PDP was more effective than ENE in restoring color to DIS- and SAM-immersed specimens.


Assuntos
Cor , Polimento Dentário , Peróxido de Hidrogênio , Peróxido de Hidrogênio/química , Polimento Dentário/métodos , Bebidas Energéticas , Profilaxia Dentária/métodos , Clareadores Dentários , Humanos , Teste de Materiais , Restauração Dentária Permanente/métodos , Materiais Dentários/química , Clareamento Dental/métodos , Cerâmica/química
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