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1.
J Environ Sci (China) ; 147: 512-522, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39003067

RESUMEN

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.


Asunto(s)
Monitoreo del Ambiente , Aprendizaje Automático , Plásticos , Espectroscopía Infrarroja Corta , Espectroscopía Infrarroja Corta/métodos , Monitoreo del Ambiente/métodos , Plásticos/análisis , Análisis de los Mínimos Cuadrados , Análisis Discriminante , Color
2.
BMC Oral Health ; 24(1): 897, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107715

RESUMEN

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.


Asunto(s)
Carbón Orgánico , Color , Esmalte Dental , Peróxido de Hidrógeno , Antisépticos Bucales , Propiedades de Superficie , Blanqueadores Dentales , Peróxido de Hidrógeno/química , Antisépticos Bucales/farmacología , Antisépticos Bucales/química , Humanos , Esmalte Dental/efectos de los fármacos , Blanqueadores Dentales/farmacología , Espectrofotometría , Blanqueamiento de Dientes/métodos
3.
Food Res Int ; 192: 114777, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147462

RESUMEN

A novel smart film MP/BNC/ACN for real-time monitoring of fish freshness was developed using myofibrillar protein (MP) and bacterial nanocellulose (BNC) as film raw materials and anthocyanin (Lycium ruthenicum, ACN) as an indicator. Firstly, the film containing 1 % ACN (MP/BNC/ACN1) was found to have a moderate thickness (0.44 ± 0.01 mm) and superior mechanical properties (tensile strength (TS) = 8.53 ± 0.11 MPa; elongation at break (EB) = 24.85 ± 1.38 %) by determining the physical structure. The covalent, electrostatic, and hydrogen bonding interactions between anthocyanin and the film matrix were identified and confirmed by FT-IR spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscope (SEM) analysis. A comprehensive evaluation concluded that MP/BNC/ACN1 exhibited excellent trimethylamine (TMA) sensitivity (total color difference (ΔE), ΔETMA0-1000 = 4.47-31.05; limit of detection (LOD), LOD = 1.03) and UV stability (ΔE96h = 4.16 ± 0.13). The performance of the films in assessing fish freshness was evaluated, principal component analysis (PCA) and hierarchical cluster analysis (HCA) revealed that MP/BNC/ACN1 (ΔE2-10d = 16.84-32.05) could clearly distinguish between fresh (0-2 d), sub-fresh (4-6 d), and spoiled (8-10 d) stages of fish, which corresponded to the film colors of red, light red, and gray-black. In conclusion, this study addresses the limitation that intelligent films cannot visually discern real-time freshness during fish storage and provides a promising approach for real-time fish freshness monitoring.


Asunto(s)
Antocianinas , Peces , Embalaje de Alimentos , Alimentos Marinos , Animales , Antocianinas/análisis , Antocianinas/química , Embalaje de Alimentos/métodos , Alimentos Marinos/análisis , Color , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Celulosa/química , Miofibrillas/química , Difracción de Rayos X
4.
Food Res Int ; 192: 114803, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147502

RESUMEN

Mannoproteins have traditionally been recognized as effective wine organoleptic modulators, however, ambiguous understanding of the relationship between their organoleptic functions and physiochemical characteristics often lead to inappropriate application in winemaking. To reveal the possible role the physiochemical characteristics of mannoproteins play in modulating wine color and aroma properties, three water-soluble mannoproteins (MP1, MP2, MP3) with different physiochemical characteristics have been prepared, and accelerated red wine aging, malvidin pigments formation experiments, accelerated aroma release experiments have been designed to observe their organoleptic modulating functions in this research. Results suggest that the phenolic/chromatic stability of red wines could be enhanced by MP3, probably due to its low steric hindrance potential, high reactivity, and good hydro-alcoholic stability conferred by its high Mannan/Glucan ratio (8.68), abundant hydrophobic/hydrophilic amino acids (65.29 % of total protein), and low/medium molecular weight level (30.71-57.77 kDa), respectively, which protected the phenolic compounds and promoted the formation of pyranoanthocyanins. Mannoproteins could modulate the volatility of aroma compounds by expelling or retention effects, which depended on the duration of mannoprotein application (the expelling effect was firstly observed possibly because of the significant adsorption of free H2O by MPs) and the types of mannoproteins. MP1 and MP2 were prone to retain and expel aroma compounds, respectively, probably due to their medium/high molecular weight levels (60.48-135.39 kDa) that conferred abundant interacting sites, and the high proportion of hydrophobic and hydrophilic components in MP1 (97.71 % polysaccharides of total mannoprotein, 34.58 % hydrophobic amino acids of total protein) and MP2 (97.96 % polysaccharides of total mannoprotein, 28.36 % hydrophobic amino acids of total protein) guaranteed a relatively higher interacting frequency with aroma compounds and free H2O molecules, respectively.


Asunto(s)
Glicoproteínas de Membrana , Odorantes , Vino , Vino/análisis , Glicoproteínas de Membrana/metabolismo , Odorantes/análisis , Color , Mucoproteínas/química , Interacciones Hidrofóbicas e Hidrofílicas , Humanos , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química
5.
Food Res Int ; 192: 114814, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147510

RESUMEN

Peruvian fava beans (PFB) are used in traditional cuisine as a nutrient-rich, flavorful, and textural ingredient; however, little is known about their industrial properties. This study evaluated the physicochemical, nutritional, and techno-functional characteristics of PFB varieties: Verde, Quelcao, and Peruanita. PFB exhibited distinct physical characteristics, quality parameters, and morphology. The color patterns of the seed coat and the hardness were the main parameters for distinguishing them. Nutritionally, all three samples exhibited high protein (23.88-24.88 g/100 g), with high proportion of essential amino acids, high dietary fiber (21.74-25.28 g/100 g), and mineral content. They also contain polyphenols (0.79-1.25 mg GAE/g) and flavonoids (0.91-1.06 mg CE/g) with antioxidant potential (16.60-21.01 and 4.68-5.17 µmol TE/g for ABTS and DPPH assays, respectively). Through XRD measurements, the semi-crystalline nature of samples was identified, belonging to the C-type crystalline form. Regarding techno-functionality, PFB flours displayed great foaming capacity, with Verde variety being the most stable. Emulsifying capacity was similar among samples, although Peruanita was more stable during heating. Upon heating with water, PFB flours reached peak viscosities between 175 and 272 cP, and final viscosities between 242 and 384 cP. Quelcao and Verde formed firmer gels after refrigeration. Based on these results, PFB would be useful to developing innovative, nutritious, and healthy products that meet market needs.


Asunto(s)
Antioxidantes , Valor Nutritivo , Polifenoles , Semillas , Vicia faba , Antioxidantes/análisis , Semillas/química , Polifenoles/análisis , Vicia faba/química , Fibras de la Dieta/análisis , Flavonoides/análisis , Perú , Color , Harina/análisis , Manipulación de Alimentos/métodos , Minerales/análisis
6.
Food Res Int ; 192: 114823, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147515

RESUMEN

This study explored how high hydrostatic pressure (HHP) and proteins (i.e., BSA and HSA) influence the color and chemical stability of cyanidin-3-O-glucoside (C3G) at neutral pH. HHP treatments (100-500 MPa, 0-20 min, 25 °C) did not affect C3G content in phosphate buffer (PB) and MOPS buffer. However, significant color loss of C3G occurred in PB due to pressure-induced pH reduction (e.g., from 7 to 4.8 at 500 MPa), which accelerated the hydration of C3G, converting it from colored to colorless species. Consequently, MOPS buffer was employed for subsequent stability experiments to assess the impact of protein and HHP on the thermal, storage, and UV light stability of C3G. Initially, rapid color loss occurred during heating and storage, primarily due to the reversible hydration of C3G until equilibrium with colorless species was reached, followed by slower parallel degradation. HSA increased the fraction of colored species at equilibrium but accelerated thermal degradation, while BSA had minimal effects. UV light irradiation accelerated the degradation of C3G colored species, causing direct degradation without conversion to colorless species, a process further intensified by the presence of proteins. HHP exhibited a negligible effect on C3G stability regardless of protein addition. These findings provide insights into anthocyanin stability under HHP and protein interactions, contributing to the development of future formulation and processing strategies for improved stability and broader applications.


Asunto(s)
Antocianinas , Color , Glucósidos , Presión Hidrostática , Antocianinas/química , Glucósidos/química , Concentración de Iones de Hidrógeno , Rayos Ultravioleta , Albúmina Sérica Bovina/química
7.
Food Res Int ; 192: 114828, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147517

RESUMEN

To enhance the drying quality of potato slices, this investigation employed a microwave heating (MH) combined with ethanol osmotic dehydration (EOD) pretreatment strategy to improve the quality of explosion puffing drying (EPD). This paper systematically investigated the effects of different pretreatment methods (no treatment, HAD, MH, EOD, MH+EOD) on the quality and physicochemical properties of potato slices subjected to CO2-EPD. The results showed that after MH and EOD pretreatments, the internal pores of the potato slices exhibited a uniform porous structure. The MH+EOD+CO2-EPD treatment demonstrated superior expansion, crispness, hardness, and color, with higher retention rates of vitamin C and protein. The measurements were an expansion ratio of 2.15, hardness of 1290.01 g, crispness of 745.94 g, ΔE of 6.54, protein content of 1.99 g/100 g, and VC content of 17.33 mg/100 g. Additionally, the study explored the effects of microwave power, microwave drying time, ethanol concentration, and ethanol soaking time on the expansion ratio, hardness, crispness, protein content, VC content, and color. MH+EOD+CO2-EPD is an environmentally sustainable and efficient solution with potential for widespread industrial application to enhance processing quality and economic benefits.


Asunto(s)
Dióxido de Carbono , Desecación , Etanol , Manipulación de Alimentos , Microondas , Solanum tuberosum , Solanum tuberosum/química , Dióxido de Carbono/análisis , Desecación/métodos , Manipulación de Alimentos/métodos , Color , Ácido Ascórbico/análisis , Dureza , Tubérculos de la Planta/química , Tubérculos de la Planta/efectos de la radiación
8.
Food Res Int ; 192: 114836, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147524

RESUMEN

The classification of carambola, also known as starfruit, according to quality parameters is usually conducted by trained human evaluators through visual inspections. This is a costly and subjective method that can generate high variability in results. As an alternative, computer vision systems (CVS) combined with deep learning (DCVS) techniques have been introduced in the industry as a powerful and an innovative tool for the rapid and non-invasive classification of fruits. However, validating the learning capability and trustworthiness of a DL model, aka black box, to obtain insights can be challenging. To reduce this gap, we propose an integrated eXplainable Artificial Intelligence (XAI) method for the classification of carambolas at different maturity stages. We compared two Residual Neural Networks (ResNet) and Visual Transformers (ViT) to identify the image regions that are enhanced by a Random Forest (RF) model, with the aim of providing more detailed information at the feature level for classifying the maturity stage. Changes in fruit colour and physicochemical data throughout the maturity stages were analysed, and the influence of these parameters on the maturity stages was evaluated using the Gradient-weighted Class Activation Mapping (Grad-CAM), the Attention Maps using RF importance. The proposed approach provides a visualization and description of the most important regions that led to the model decision, in wide visualization follows the models an importance features from RF. Our approach has promising potential for standardized and rapid carambolas classification, achieving 91 % accuracy with ResNet and 95 % with ViT, with potential application for other fruits.


Asunto(s)
Averrhoa , Frutas , Redes Neurales de la Computación , Frutas/crecimiento & desarrollo , Frutas/clasificación , Averrhoa/química , Aprendizaje Profundo , Inteligencia Artificial , Color
9.
Food Res Int ; 192: 114844, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39147527

RESUMEN

Non-digestible oligosaccharides (OS) and allulose have beneficial health properties and could reduce the amount of added sugar in baked goods. In this study allulose and various OS [fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), lactosucrose (LOS), isomalto-oligosaccharides (IMO), Promitor 70R (P70R), and xylo-oligosaccharides (XOS)] were added to a wire-cut cookie formulation at concentrations determined to have similar effects on the gelatinization temperature (Tgel) of starch relative to sucrose. Different baking performance attributes of the doughs and cookies were assessed, including: appearance, spread, color, texture, and % moisture loss after baking. The results were correlated to: OS solution and solid properties and OS effects on starch thermal events (gelatinization, pasting, and retrogradation). The Tgel-matching formulation protocol was effective in producing reduced-sugar cookies which had similar appearance, color, and spread attributes compared to the sucrose control; however, cookie texture significantly varied. Cookies containing allulose were the least similar to the control, having darker color, reduced spread, and softer cake-like texture. The only OS cookies that matched the texture of the sucrose control contained LOS, while P70R cookies were the hardest. Cookie texture correlated strongly with the % total moisture loss after baking (r = -0.8763) and was best explained by OS solution viscosity: more viscous OS solutions limited moisture release and resulted in harder cookies. The Tgel of starch also correlated with OS solution viscosity (r = 0.7861) and should be accounted for in reduced sugar applications. The OS recommended as sucrose replacers in cookies based on principal component analysis groupings were: XOS > IMO > LOS > and GOS.


Asunto(s)
Oligosacáridos , Oligosacáridos/química , Culinaria/métodos , Sacarosa/química , Almidón/química , Color , Agua/química , Fructosa/química , Manipulación de Alimentos/métodos , Viscosidad , Temperatura
10.
J Vis Exp ; (209)2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39141539

RESUMEN

Matcha, as a healthy food additive, has been widely utilized in traditional foods such as noodles, cookies, and bread. However, there are several challenges that must be addressed in the quality of matcha-incorporated foods, with the most significant being the prevention of matcha discoloration. In this study, we introduce a novel approach involving the incorporation of matcha with whey protein (0.08 g/mL) and carboxymethyl chitosan (0.04 g/mL), accompanied by microwave treatment at 700 W for 60 s of wheat flour to produce color-stable matcha fresh noodles. All steps involved in the production process of matcha fresh noodles are presented in the article, including matcha embedding treatment, microwave treatment of wheat flour, kneading the dough, leaving to prove, dividing the dough, rolling out the dough and slicing the sheets by noodle press. The findings revealed a 72.13% reduction in discoloration of fresh matcha noodles following embedding and microwave treatment, compared to untreated fresh matcha noodles. Moreover, the combined process did not have any detrimental impact on the sensory attributes of matcha noodles, including their aroma and taste. Therefore, the novel method proposed in this study holds significant potential for enhancing the color stability of fresh matcha noodles during preparation.


Asunto(s)
Manipulación de Alimentos , Microondas , Manipulación de Alimentos/métodos , Color , Harina , Proteína de Suero de Leche/química , Aditivos Alimentarios/química , Triticum/química , Quitosano/química
11.
Luminescence ; 39(8): e4864, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39143604

RESUMEN

The GdAl3(BO3)4:xPr3+ (0 ≤ x ≤ 5.0 mol%) phosphors were prepared through solid state reaction route and characterized for various lighting applications. Powder X-ray diffraction investigations revel rhombohedral structure matched to JCPDS card no. 83-1907. The morphological studies confirm the agglomeration of particles with different size and shape. The emission spectra show various emission transitions originating from Pr3+:(3P1,0, 1D2) emission states to their lower lying energy states upon 274 nm NUV excitation with a red shift for x > 0.5 mol%. The colour perception analysis results an intense red luminescence due to efficient energy transfer from Gd3+ to Pr3+ ions. The temperature-dependent luminescence investigations show good thermal stability even beyond 150°C with an activation energy of 0.24 eV. The observed experimental results show the potentiality of GdAl3(BO3)4:0.5 Pr3+ phosphor for red emitting devices and red component in phosphor converted white LEDs.


Asunto(s)
Gadolinio , Luminiscencia , Sustancias Luminiscentes , Gadolinio/química , Sustancias Luminiscentes/química , Mediciones Luminiscentes , Praseodimio/química , Difracción de Rayos X , Tamaño de la Partícula , Temperatura , Color
12.
Lasers Med Sci ; 39(1): 217, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39145805

RESUMEN

This in vitro study aimed to investigate potential changes in the color and roughness of dental enamel resulting from the use of different toothpaste formulations during bleaching with violet LED light (405 nm). Sixty specimens of bovine incisors, each measuring 6 × 6 × 3 mm, were segregated into six distinct experimental groups based on their respective treatments (n = 10): C + VL: Brushing with Colgate® Total 12 + bleaching with violet LED; LB + VL: Brushing with Colgate® Luminous White Brilliant + bleaching with violet LED; LI + VL: Brushing with Colgate® Luminous White Instant + violet LED bleaching; C: Brushing with Colgate® Total 12; LB: Brushing with Colgate® Luminous White Brilliant; LI: Brushing with Colgate® Luminous White Instant. The examined variables included alterations in color (∆L*, ∆a*, ∆b*, ∆Eab, and ∆E00), surface roughness (Ra), and scanning electron microscopy observations. No statistically significant distinctions emerged in total color variations (∆E00 and ∆E) among the groups under scrutiny. Notably, the groups that employed Colgate® Luminous White Instant displayed elevated roughness values, irrespective of their association with violet LED, as corroborated by scanning electron microscopy examinations. It can be concluded that whitening toothpastes associated to violet LED do not influence the color change of dental enamel in fifteen days of treatment. Toothpastes with a higher number of abrasive particles showed greater changes in enamel roughness, regardless of the use of violet LED.


Asunto(s)
Color , Esmalte Dental , Propiedades de Superficie , Blanqueadores Dentales , Blanqueamiento de Dientes , Pastas de Dientes , Esmalte Dental/efectos de los fármacos , Esmalte Dental/efectos de la radiación , Bovinos , Animales , Pastas de Dientes/química , Blanqueamiento de Dientes/métodos , Blanqueamiento de Dientes/efectos adversos , Propiedades de Superficie/efectos de los fármacos , Blanqueadores Dentales/efectos adversos , Técnicas In Vitro , Microscopía Electrónica de Rastreo
13.
Gen Dent ; 72(5): 38-41, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39151080

RESUMEN

The aim of this study was to evaluate the influence of different mouthwash solutions on the color stability of a nanohybrid composite resin. Forty discs of Luna nanohybrid composite resin were prepared and randomly assigned to 4 experimental groups (n = 10), determined by the type of immersion solution: distilled water (DW); Oral-B Pro-Health mouthwash (OBPH); Listerine Total Care mouthwash (LTC); or Colgate Plax Infinity mouthwash (CPI). The discs were immersed in solution for 30 minutes a day and stored at 37°C for 24 hours. Digital photographs of each specimen were taken at each timepoint and transferred to a computer program for color analysis. The International Commission on Illumination L*a*b* system was used to analyze the color of the specimens at baseline and the overall color change (ΔE*) at baseline, 30 days, 60 days, and 90 days. Two-way analysis of variance was used to evaluate the influence of solution and time on ΔE* values (α = 0.05). The t test was used as a post hoc test to compare the mean values between groups (α = 0.05). After 30 days, all groups showed small color change values compared with baseline (ΔE*1 < 1.0). However, after 60 days, the LTC and CPI groups showed greater color change (ΔE*2) than the other groups, and the difference was statistically significant (P < 0.05). After 90 days, all groups differed significantly compared with the control group (P < 0.05), and all mouthwash groups presented color change values that are considered clinically unacceptable (ΔE*3 > 3.0). The results of this in vitro study indicate that mouthwash solutions do not cause significant color changes in nanohybrid composite resin for a period of up to 30 days; however, longer periods (90 days) of exposure could make the restorative material esthetically unacceptable.


Asunto(s)
Color , Resinas Compuestas , Antisépticos Bucales , Antisépticos Bucales/química , Resinas Compuestas/uso terapéutico , Resinas Compuestas/química , Nanocompuestos , Humanos , Ensayo de Materiales , Combinación de Medicamentos , Salicilatos , Terpenos
14.
Gen Dent ; 72(5): 49-53, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39151082

RESUMEN

This in vitro study evaluated the influence of radiant exposure and material shade on the degree of conversion (DC) and microhardness of a resin-based composite (RBC). Sixty-four RBC specimens in shades A1E (enamel) and A4D (dentin) were light cured at a calibrated exitance of 1000 mW/cm2 for 5, 10, 15, or 20 seconds, resulting in radiant exposure levels of 5, 10, 15, or 20 J/cm2. The DC was determined using Fourier-transform infrared spectroscopy (n = 3 per shade per exposure level). The Knoop hardness number (KHN) was measured on the top and bottom surfaces of each specimen (n = 5 per shade per exposure level). Data were analyzed using 2- and 3-way analyses of variance and post hoc Tukey tests (α = 0.05). The RBC shade did not affect the DC (P = 0.860), and the lowest DC values were achieved with an exposure level of 5 J/cm2 (P < 0.001). The shade did not affect the KHN on the top surface, but the radiant exposure level did, with the application of 5 J/cm2 resulting in significantly lower values (P < 0.05). For the bottom surface, shade A1E showed significantly higher KHN values than A4D (P < 0.001). An increase in the radiant exposure led to increased DC and KHN for both shades of RBC until reaching a saturation point of 10 J/cm2 for A1E and the top surface of A4D. The darker and more opaque shade was not adequately polymerized at a 2-mm depth, even when the highest radiant exposure level was applied.


Asunto(s)
Resinas Compuestas , Dureza , Ensayo de Materiales , Resinas Compuestas/química , Resinas Compuestas/uso terapéutico , Espectroscopía Infrarroja por Transformada de Fourier , Color , Humanos , Polimerizacion , Propiedades de Superficie , Luces de Curación Dental , Técnicas In Vitro , Materiales Dentales/química , Curación por Luz de Adhesivos Dentales/métodos
15.
Curr Biol ; 34(15): R722-R723, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39106826

RESUMEN

Camouflage is vital for the survival of many prey species1,2, including ground-nesting birds3,4,5,6. Egg camouflage via background matching and disruptive coloration (high contrast markings that break up the body outline) is often behaviourally mediated by selecting substrates that enhance egg camouflage1,2,3,4,5,6. However, the mechanisms controlling this behaviour in birds have remained unknown. Several, not mutually exclusive, mechanisms have been suggested to control background choice for egg camouflage7. These include where individual background preferences are genetically linked to egg coloration, enabled through learning egg appearances from previous breeding attempts, or modified by imprinting on visual backgrounds during early life7, Here, using predator vision models, we compared the camouflage of Japanese quail (Coturnix japonica) eggs among females who were allowed to choose one of four coloured substrates on which to lay3. Birds were divided into experienced females who had been given the opportunity to observe the appearance of their eggs, versus naïve females breeding for the first time. Our experiment revealed that breeding experience leads to improved background choices made for egg background matching. However, substrate choice for disruptive coloration appeared genetically determined, as both bird groups chose backgrounds that enhanced egg disruptiveness regardless of experience. These mechanisms underpin behaviours that are likely essential for birds and other animals to optimise camouflage and avoid predation6.


Asunto(s)
Coturnix , Animales , Femenino , Coturnix/fisiología , Óvulo/fisiología , Comportamiento de Nidificación , Pigmentación , Conducta de Elección/fisiología , Color , Mimetismo Biológico , Aprendizaje/fisiología
16.
Luminescence ; 39(8): e4852, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39108144

RESUMEN

In this paper, nitrogen-doped carbon quantum dots (N-CQDs) are synthesized by the hydrothermal method. N-CQDs exhibit strong fluorescence, and N-CQDs are well dispersed in water as well as in various organic solvents. N-CQDs emit multi-color fluorescence from blue to red, with wavelengths in the range of 450-650 nm without the need for purification. Furthermore, the fluorescence emission of N-CQDs was selectively quenched after adding Fe3+ ions. N-CQDs were used as a nanoprobe for the detection of Fe3+ ions, showing a good linear correlation between the fluorescence emission and the concentration of Fe3+ in the Fe3+ concentration range from 0 to 100 µM. The limit of detection (LOD) was 55.7 µM for Fe3+ in water and 40.2 µM in fetal bovine serum (FBS) samples. The study shows that the synthesized N-CQDs have low cost and great potential for application in biological analysis.


Asunto(s)
Carbono , Hierro , Nitrógeno , Puntos Cuánticos , Puntos Cuánticos/química , Carbono/química , Nitrógeno/química , Hierro/análisis , Hierro/química , Animales , Bovinos , Espectrometría de Fluorescencia , Iones/análisis , Límite de Detección , Fluorescencia , Color
17.
Clin Oral Investig ; 28(9): 473, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110133

RESUMEN

PURPOSE: To investigate the effects of different surface treatments and thicknesses on the color, transparency, and surface roughness of ultra-transparent zirconia. METHODS: A total of 120 Katana ultra-translucent multi-layered zirconia specimens were divided into 12 groups according to the thickness (0.3, 0.5, and 0.7 mm) and surface treatment (control, airborne particle abrasion [APA], lithium disilicate coating, and glaze on). Color difference (ΔE00) and relative translucency parameter (RTP00) were calculated using a digital spectrophotometer. The surface roughness (Ra, Rq, Sa, and Sq) was measured using a non-contact profile scanner. The surface morphologies and microstructures of the samples were observed using a tungsten filament scanning electron microscope. Statistical analyses were performed by one-way and two-way analysis of variance (ANOVA) followed by post hoc multiple comparisons and Pearson's correlation (α = 0.05). RESULTS: The results showed that the surface treatment, ceramic thickness, and their interactions had significant effects on ΔE00 and RTP00 (p < 0.001). The surface treatment significantly altered the micromorphology and increased the surface roughness of the ceramic samples. APA exhibited the lowest transparency, largest color difference, and highest surface roughness. Zirconia with 0.3 mm and 0.7 mm thicknesses showed strong negative correlations between Sa and RTP00. CONCLUSIONS: The three internal surface treatments significantly altered the surface roughness, color difference, and transparency of ultra-transparent zirconia. As the thickness increased, the influence of the inner surface treatment on the color difference and transparency of zirconia decreased. CLINICAL IMPLICATIONS: For new zirconia internal surface treatment technologies, in addition to considering the enhancement effect on the bonding properties, the potential effects on the color and translucency of high-transparency zirconia should also be considered. Appropriately increasing the thickness of zirconia restorations helps minimize the effect of surface treatment on the optical properties.


Asunto(s)
Color , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Espectrofotometría , Propiedades de Superficie , Circonio , Circonio/química , Porcelana Dental/química , Materiales Dentales/química , Recubrimiento Dental Adhesivo/métodos
18.
Sensors (Basel) ; 24(15)2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39123974

RESUMEN

Current international optical science research focuses on the non-visual effects of lighting on human cognition, mood, and biological rhythms to enhance overall well-being. Nocturnal roadway lighting, in particular, has a substantial impact on drivers' physiological and psychological states, influencing behavior and safety. This study investigates the non-visual effects of correlated color temperature (CCT: 3000K vs. 4000K vs. 5000K) and illuminance levels (20 lx vs. 30 lx) of urban motor vehicle road lighting on driver alertness during various driving tasks. Conducted between 19:00 and 20:30, the experiments utilized a human-vehicle-light simulation platform. EEG (ß waves), reaction time, and subjective evaluations using the Karolinska Sleepiness Scale (KSS) were measured. The results indicated that the interaction between CCT and illuminance, as well as between CCT and task type, significantly influenced driver alertness. However, no significant effect of CCT and illuminance on reaction time was observed. The findings suggest that higher illuminance (30 lx) combined with medium CCT (4000K) effectively reduces reaction time. This investigation enriches related research, provides valuable reference for future studies, and enhances understanding of the mechanisms of lighting's influence on driver alertness. Moreover, the findings have significant implications for optimizing the design of urban road lighting.


Asunto(s)
Conducción de Automóvil , Color , Iluminación , Vehículos a Motor , Tiempo de Reacción , Temperatura , Humanos , Adulto , Masculino , Femenino , Tiempo de Reacción/fisiología , Electroencefalografía/métodos , Adulto Joven , Atención/fisiología
19.
PLoS One ; 19(8): e0306649, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39121086

RESUMEN

This paper explores whether it is feasible to use the RGB color information in images of wheat canopies that were exposed to low temperatures during the growth season to achieve fast, non-destructive, and accurate determination of the severity of any freeze injury it may have incurred. For the study presented in this paper, we compared the accuracy of a number of algorithmic classification models using either meteorological data reported by weather services or the color gradation skewness-distribution from high-definition digital canopy images acquired in situ as inputs against a reference obtained by manually assessing the severity of the freeze injury inflicted upon wheat populations at three experimental stations in Shandong, China. The algorithms we used to construct the models included in our study were based on either K-means clustering, systematic clustering, or naïve Bayesian classification. When analyzing the reliability of our models, we found that, at more than 85%, the accuracy of the Bayesian model, which used the color information as inputs and involved the use of prior data in the form of the reference data we had obtained through manual classification, was significantly higher than that of the models based on systematic or the K-means clustering, which did not involve the use of prior data. It was interesting to note that the determination accuracy of algorithms using meteorological factors as inputs was significantly lower than that of those using color information. We also noted that the determination accuracy of the Bayesian model had some potential for optimization, which prompted us to subject the inputs of the model to a factor analysis in order to identify the key independent leaf color distribution parameters characterizing wheat freeze injury severity. This optimization allowed us to improve the determination accuracy of the model to over 90%, even in environments comprising several different ecological zones, as was the case at one of our experimental sites. In conclusion, our naïve Bayesian classification algorithm, which uses six key color gradation skewness-distribution parameters as inputs and involves the use of prior data in the form of manual assessments, qualifies as a contender for the development of commercial-grade wheat freeze injury severity monitoring systems supporting post-freeze management measures aimed at ensuring food security.


Asunto(s)
Algoritmos , Teorema de Bayes , Color , Triticum , Congelación , Hojas de la Planta , China , Procesamiento de Imagen Asistido por Computador/métodos
20.
Pediatr Dent ; 46(4): 277-284, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39123328

RESUMEN

Purpose: The purpose of this study was to assess, in vitro, the color stability and bleaching response of three bulk-fill composite resins-Activa™, Tetric®-N-Ceram Bulk-Fill, and Filtek™ One Bulk-Fill???and one conventional composite resin, Filtek™ Z250, after immersion in commonly consumed carbonated beverages and subsequent home bleaching with 15 percent carbamide peroxide. Methods: Ninety-six samples (two- and four-mm thick) of the materials were immersed in malt drink, energy drink, cola, or distilled water for one day, one week, and two months. After two months, samples underwent home bleaching with 15 percent carbamide peroxide gel. Spectrophotometric analysis measured color and whiteness changes pre-immersion, post-immersion, and post-bleaching. Statistical significance was determined using factorial mixed analysis of variance (ANOVA), three-way ANOVA, and Bonferroni post hoc tests (P<0.05). Results: All tested composite resins exhibited unacceptable discoloration (color change greater than 3.3) after two months in carbonated beverages. Filtek™ One Bulk-Fill and Filtek™ Z250 displayed the most significant discoloration, particularly when immersed in the malt drink (P<0.05). In contrast, Activa™ samples reached unacceptable discoloration within just one week in malt and cola drinks. Home bleaching yielded limited whiteness recovery, with Activa™ presenting acceptable whiteness post-bleaching after staining with cola and energy drinks. Conclusions: This study highlights the aesthetic risks of prolonged carbonated beverage consumption and the limitations of the assessed home bleaching technique using 15 percent carbamide peroxide. Enhanced dental education on the dietary effects of some beverages on restorative materials is indicated by these findings.


Asunto(s)
Peróxido de Carbamida , Bebidas Gaseosas , Color , Resinas Compuestas , Blanqueamiento de Dientes , Blanqueamiento de Dientes/métodos , Blanqueadores Dentales , Humanos , Peróxidos/efectos adversos , Urea/análogos & derivados , Urea/efectos adversos , Ensayo de Materiales , Espectrofotometría , Bebidas Energéticas
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