Development of the color scale of perceived exertion: preliminary validation

This study developed a Color Scale of Perceived Exertion (RPE-color scale) and assessed its concurrent and construct validity in adult women. One hundred participants (18-77 years), who were habitual exercisers, associated colors with verbal anchors of the Borg RPE scale (RPE-Borg scale) for RPE-color scale development. For RPE-color scale validation, 12 Young (M = 21.7 yr., SD = 1.5) and 10 Older (M = 60.3 yr., SD = 3.5) adult women performed a maximal graded exercise test on a treadmill and reported perceived exertion in both RPE-color and RPE-Borg scales. In the Young group, the RPE-color scale was significantly associated with heart rate and oxygen consumption, having strong correlations with the RPE-Borg scale. In the Older group, the RPE-color scale was significantly associated with heart rate, having moderate to high correlations with the RPE-Borg scale. The RPE-color scale demonstrated concurrent and construct validity in the Young women, as well as construct validity in Older adults.

Estimation of hourly, daily and monthly mean diffuse radiation based on MEO shadowring correction

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of polymerization methods and thermal cycling on color stability of acrylic resin denture teeth

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Composite resin color stability: influence of light sources and immersion media

This study evaluated the influence of light sources and immersion media on the color stability of a nanofilled composite resin. Conventional halogen, high-power-density halogen and high-power-density light-emitting diode (LED) units were used. There were 4 immersion media: coffee, tea, Coke® and artificial saliva. A total of 180 specimens (10 mm x 2 mm) were prepared, immersed in artificial saliva for 24 h at 37±1ºC, and had their initial color measured with a spectrophotometer according to the CIELab system. Then, the specimens were immersed in the 4 media during 60 days. Data from the color change and luminosity were collected and subjected to statistical analysis by the Kruskall-Wallis test (p<0.05). For immersion time, the data were subjected to two-way ANOVA test and Fisher's test (p<0.05). High-power-density LED (ΔE=1.91) promoted similar color stability of the composite resin to that of the tested halogen curing units (Jet Lite 4000 plus--ΔE=2.05; XL 3000--ΔE=2.28). Coffee (ΔE=8.40; ΔL=-5.21) showed the highest influence on color stability of the studied composite resin. There was no significant difference in color stability regardless of the light sources, and coffee was the immersion medium that promoted the highest color changes on the tested composite resin.

Effect of postpolymerization method on the color stability of composite resins submitted to ultraviolet aging

The aim of this research was to evaluate the effect of postpolymerization method on the color stability of resin-based composites. Samples of direct and indirect restorative materials were polymerized with two photo-curing units (Visio photo-curing oven system and LED Elipar Freelight 2). All samples were submitted to an initial chromatic analysis using a spectrometer and submitted to ultraviolet-accelerated artificial aging. The direct material showed less color change than the indirect material, independent of the photo-activation method used. Samples photo cured with the LED system showed less change than those photo cured with the Visio system. The postpolymerization oven did not improve the color stability of direct and indirect resin-based composites.

Effects of dental bleaching on the color, translucency and fluorescence properties of enamel and dentin

The objective of this study was to evaluate the color, translucency and fluorescence of bovine enamel and dentin submitted to different bleaching modalities. Pairs of enamel and dentin discs (3 mm in diameter) were obtained from 150 bovine teeth. In 75 of the pairs, one specimen had the enamel removed (Dentin Group). The dentin was removed from one specimen of the remaining 75 pairs (Enamel Group) and the other specimen was left unaltered (Enamel + Dentin). The evaluation of color, translucency and fluorescence was performed with a spectrophotometer using the CIE L* a* b*. Each group was subdivided into three subgroups: Control, composed of specimens that were not bleached, and two experimental subgroups, bleached with either 10% carbamide peroxide (CP10%) or 35% hydrogen peroxide (HP35%). The CP10% bleaching gel was applied 2 h/day for 14 days. The HP35% bleaching agent was applied using two applications of 30 min each, with a one week interval between each application. When not being bleached, the specimens were immersed in artificial saliva. The color, translucency and fluorescence ratings were assessed using spectrophotometry 7 days after the treatment. Regarding color, significant differences were found between bleaching techniques in the groups Enamel and Enamel + Dentin, with a higher color difference for HP35%. Bleaching did not change the translucency of the dental tissues. There were significant differences for fluorescence for the HP35% subgroups of Dentin and Enamel + Dentin, and for the CP10% subgroup of Enamel. Dental bleaching changed the color and fluorescence of the dental tissues, however translucency was not affected.

Early correction of malocclusion using planas direct tracks

The correction of functional posterior crossbite through Planas Direct Tracks has many characteristics that can become advantages. The aim of this study was to present a clinical case showing how to use this procedure for early correction with resources available through public health services. The patient, a 4-year-old girl, arrived to receive treatment due to a functional unilateral crossbite. When the mandible was moved to the centric position, it was observed that the teeth had occlusal trauma. An occlusal adjustment was performed. The adjustment was not sufficient to promote functional equilibrium; thus, Planas Direct Tracks were made, resulting in functional equilibrium and correction of the malocclusion. As shown in the case report, the Planas Direct Tracks were effective for the correction of the posterior crossbite. If malocclusion is considered a public health problem, implementation of low-cost and easy-to-execute techniques is needed.

Color stability of the artificial iris button in an ocular prosthesis before and after acrylic resin polymerization

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of whitening gel application protocol on dental color change

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cytotoxic and genotoxic effects of two hair dyes used in the formulation of black color

According to the International Agency for Research on Cancer (IARC), some hair dyes are considered mutagenic and carcinogenic in in vitro assays and exposed human populations. Epidemiological studies indicate that hairdressers occupationally exposed to hair dyes have a higher risk of developing bladder cancer. In Brazil, 26% of the adults use hair dye. In this study, we investigated the toxic effects of two hair dyes, Basic Red 51 (BR51) and Basic Brown 17 (BB17), which are temporary dyes of the azo group (R-N=N-R'), used in the composition of the black hair dye. To this end, MTT and trypan blue assays (cytotoxicity), comet and micronucleus assay (genotoxicity) were applied, with HepG2 cells. For cytotoxic assessment, dyes were tested in serial dilutions, being the highest concentrations those used in the commercial formula for hair dyes. For genotoxic assessment concentrations were selected according to cell viability. Results showed that both dyes induced significant cytotoxic and genotoxic effects in the cells, in concentrations much lower than those used in the commercial formula. Genotoxic effects could be related to the azo structure present in the composition of the dyes, which is known as mutagenic and carcinogenic. These results point to the hazard of the hair dye exposure to human health.

Soft color enhancement of the production of J/psi's by neutrinos

We calculate the production of J/ψ mesons by neutrino-nucleon collisions in fixed target experiments. Soft color, often referred to as color evaporation effects, enhances production cross sections due to the contribution of color octet states. Though still small, J/ψ production may be observable in present and future experiments such as NuTeV and μ colliders. ©2001 The American Physical Society.

Composite resin color stability: influence of light sources and immersion media

This study evaluated the influence of light sources and immersion media on the color stability of a nanofilled composite resin. Conventional halogen, high-power-density halogen and high-power-density light-emitting diode (LED) units were used. There were 4 immersion media: coffee, tea, Coke® and artificial saliva. A total of 180 specimens (10 mm x 2 mm) were prepared, immersed in artificial saliva for 24 h at 37±1ºC, and had their initial color measured with a spectrophotometer according to the CIELab system. Then, the specimens were immersed in the 4 media during 60 days. Data from the color change and luminosity were collected and subjected to statistical analysis by the Kruskall-Wallis test (p<0.05). For immersion time, the data were subjected to two-way ANOVA test and Fisher's test (p<0.05). High-power-density LED (ΔE=1.91) promoted similar color stability of the composite resin to that of the tested halogen curing units (Jet Lite 4000 plus--ΔE=2.05; XL 3000--ΔE=2.28). Coffee (ΔE=8.40; ΔL=-5.21) showed the highest influence on color stability of the studied composite resin. There was no significant difference in color stability regardless of the light sources, and coffee was the immersion medium that promoted the highest color changes on the tested composite resin.

Bacterial oxycarotenoids added into broiler chickens ration modify breast meat color

Some markets around the world demand for well pigmented poultry products, what justifies the intentional use of synthetic additives in rations during breeding. The inconvenient for that practice most times is the elevated price of these products, beyond the argument of being chemicals, which may not be viable for some production systems. So, the aim of this experiment was to check on the ability of natural red oxycarotenoids produced by R. gelatinosus to modify broilers breast meat color. Bacterial biomass containing oxycarotenoids were added into Cobb broilers finisher diets at 0, 1.0, 2.0 and 3.0 g/kg and fed during 10 days (35-45 d). Five replicates (10 birds each) were performed. At days 35, 37, 39, 41, 43 and 45, 100 birds were slaughtered scalded, defeathered and eviscerated. Data on live and carcass weights were recorded. After cooling, color parameters of meat were determined on breast surface using a HunterLab XE Plus colorimeter calibrated with black and white standard tiles. Regression analysis was used for the investigation of relationships between days of consumption and biomass concentration on color values, live weight and carcass yield. Results showed that redness of breast meat was significantly influenced by the biomass concentration in a linear effect (P=0.0056) and also by the time of consumption, in a quadratic effect (P=0.0232). Days of consumption also affected yellowness and lightness with significant quadratic responses (P=0.0225 and P<0.0001, respectively). Birds live weight increased significantly during the application of the experimental diets (P<0.0001), showing no negative influence of the biomass administration. Also no deleterious effects derived from the application of the product were observed on carcass yield. So we concluded that R. gelatinosus oxycarotenoids present in the bacterial biomass can modify broilers breast meat color, performing as an alternative pigmenting additive in poultry production.

Yolks color definition by supplementing yellow and red xanthophylls to hen's diets

Egg yolk color may be controlled both by the concentration and the type of xanthophylls added to diets, with the aim of meeting consumers demand. The objectives of this work were to study how yellow and red xanthophylls present in laying hens` diets influence yolks colors and find the concentrations of these ingredients that meet the regional consumer desire. A factorial design 5 x 3 with 5 concentrations of yellow xanthophylls (lutein + zeaxantin 40%; 1.0, 1.25, 1.5, 1.75 and 2.0 mg/hen/d) and 3 concentrations of red xanthophylls (canthaxantin 10%; 0, 0.35, 0.7 mg/hen/d) was used. After a 30 d period receiving corn basal diets and water ad libitum, 60 White Dekalbe hens were distributed to receive the 15 dietary treatments in 4 replicates. Diets were provided daily at 110 g, during 21 d under 16 h light/8 h dark. Yolks colors were evaluated daily using the CIE L, a, b color space and the Roche color index. After the color stabilization, data were analyzed by ANOVA, regression analysis and Response Surface Methodology (MRS). Global acceptance for the Roche colors was evaluated with a 5 points hedonic scale and data were analyzed by Friedman and Dunn tests. Significance was established at 95% (P < 0.05). Regression analysis showed that the red xanthophylls content was the most important factor that defined L, a and b values for yolk color (P < 0.0001; square function), although its effect was significantly affected by the yellow xanthophylls contents (P = 0.0277; P < 0.0001; P = 0.0002 for L, a, b, respectively), providing evidence for a synergistic effect and not for a saturation effect. MRS showed that the highest redness of yolks was reached with 1.5 mg/hen/d of yellow and 0.5 mg/hen/d of red xanthophylls. So, higher supplementations aiming at increasing yolk color would bring an unnecessary cost to the ration. The most accepted yolk color scored 9, which corresponded to mean color attributes L = 65; a = 16; and b = 64. MRS showed that these values could be reached with combinations of yellow:red xanthophylls like 1.0:0.15 or 1.5:0.1 mg/ hen/d or simply with the yellow xanthophylls at 2.0 mg/hen/d. So, it was concluded that both yellow and red xanthophylls are important to define yolks color; that high amounts of xanthophylls are unnecessary to bring changes to color; and that Brazilian consumer requires yolks color attainable with few amounts of red xanthophylls or only with the yellow ones.

Segmental osteotomy for the correction of a malpositioned single implant: an 8-year follow-up

This case report is an 8-year follow-up of a malpositioned single implant, which was treated with segmental osteotomy, to confirm the treatment's characteristics, indications, and advantages. Deep buccal positioning of an endosseous implant placed in the maxillary left central incisor area did not permit acceptable prosthetic rehabilitation, despite its favorable bone insertion with no significant marginal bone loss. The surgical procedure included osteotomy and block movement performed toward the lingual and cervical position, fixed with a provisional prosthesis and miniplates and mini-implants. A connective tissue graft was necessary for esthetics optimization and was performed in a second stage. Advantages including the prevention of alveolar ridge damage, the improvement of gingival contour, and the use of an already integrated implant are presented. Clinically satisfactory hard and soft tissue stability permitted us to consider segmental surgery as a reliable alternative for malpositioned osseointegrated implants.