• Imaging Science in Dentistry
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• v.46 no.1
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• pp.25-31
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• 2016

Purpose: This study was performed to evaluate condylar surface changes and remodeling after orthognathic surgery using three-dimensional computed tomography (3D CT) imaging, including comparisons between the right and left sides and between the sexes. Materials and Methods: Forty patients (20 males and 20 females) who underwent multi-detector CT examinations before and after surgery were selected. Three-dimensional images comprising thousands of points on the condylar surface were obtained before and after surgery. For the quantitative assessment of condylar surface changes, point-to-point (preoperative-to-postoperative) distances were calculated using 3D processing software. These point-to-point distances were converted to a color map. In order to evaluate the types of condylar remodeling, the condylar head was divided into six areas (anteromedial, anteromiddle, anterolateral, posteromedial, posteromiddle, and posterolateral areas) and each area was classified into three types of condylar remodeling (bone formation, no change, and bone resorption) based on the color map. Additionally, comparative analyses were performed between the right and left sides and according to sex. Results: The mean of the average point-to-point distances on condylar surface was $0.11{\pm}0.03mm$. Bone resorption occurred more frequently than other types of condylar remodeling, especially in the lateral areas. However, bone formation in the anteromedial area was particularly prominent. No significant difference was found between the right and left condyles, but condylar surface changes in males were significantly larger than in females. Conclusion: This study revealed that condylar remodeling exhibited a tendency towards bone resorption, especially in the lateral areas. Condylar surface changes occurred, but were small.

• Journal of Conservation Science
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• v.28 no.1
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• pp.29-37
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• 2012

This study discusses a mercury amalgam gilding technique and examines how the color, surface and section of the gilt layer changes as the condition of heat treatment with mercury amalgam gilt object is changed. Some previous studies have mentioned reasons for various colors on gilt bronze artifacts depending on gilding manufacture and environment. However, reason for reddish color with gold on the artifacts' surface brought on high temperature corrosion has yet to be discussed and analyzed. A methodology was found in representing the mercury amalgam gilding technique and heat treatment test. According to the result of the heat treatment test, in the conditions of higher temperature and longer time, the oxidized layer on the gilt layer was distributed more widely and in the part when the oxide layer was eliminated, the gilt layer with a reddish color was observed. Moreover, in the surface observation of the specimen on which yellow and reddish colors were agitated, the changing aspects of its surface condition differed by colors. When investigated the section, it was observed that the void density and size became larger. After a test, the surface components changed; the temperature of heat treatment increased, component ratio of Hg and Au decreased gradually but component ratio of Cu increased. In regard to the gilt layer, as the time was longer and the temperature became higher for the heat treatment, the component ratio of Au and Cu by layers tended to change in inverse proportion. It is concluded that gilding techniques and the burial environment can make a difference in the surface color of the gilt layer on the gilt bronze artifacts, the high temperature corrosion that occurs by heat after they are manufactured is also one of the factors that affects their surface color.

• Restorative Dentistry and Endodontics
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• v.47 no.4
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• pp.43.1-43.13
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• 2022

Objectives: This study compared the surface gloss (SG), gloss retention (GR), and color stability (CS) of 2 universal resin composites after chemical (CA) and mechanical (MA) aging. Materials and Methods: Twenty disc-shaped samples of G-ænial A'Chord (GC-Europe) and Filtek Universal (3M-ESPE) were polished with sequential abrasive papers. For CA, specimens were stored in 1 mL of 75% ethanol for 15 days at 37℃, and readings (SG, GR, and CS) were obtained at baseline and 5, 10, and 15 days. For MA, specimens were subjected to 10,750 simulated brushing cycles. SG and CS were evaluated after every 3,583 cycles. SG was measured with a glossmeter (geometrical configuration: 60°), and values were expressed in gloss units. Color was measured with a spectrophotometer using the CIE-L^*a^*b^* color system. The Student's t-test, 1-way analysis of variance, and Scheffé test were used for statistical analysis (α = 0.05). Results: G-ænial presented significantly higher SG values than Filtek (p = 0.02), with GR reductions of 5.2% (CA) and 5.3% (MA) for G-ænial and 7.6% (CA) and 7.2% (MA) for Filtek. The aging protocol had no statistically significant effect on SG or GR (p = 0.25) from baseline to the final readings. G-ænial-MA presented the lowest color difference (ΔE = 1.8), and G-ænial-CA and Filtek-CA had the largest changes (ΔE = 8.6 and ΔE = 11.8, respectively). Conclusion: G-ænial presented higher SG values and better CS. Both restorative materials demonstrated acceptable GR and CS. Aging protocols impacted these properties negatively.

• The korean journal of orthodontics
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• v.23 no.3 s.42
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• pp.327-340
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• 1993

The purpose of this study was to estimate the possibility of practical application of TiN ion-plating method on orthodontic appliances. TiN was coated on the surface of orthodontic stainless steel roll band by means of ion-plating method, and colorimetric properties of its obtained TiN film were investigated by using color analyzer. Also its corrosion and discoloration properties were compared with those of non ion-plated stainless steel roll band by using immersion test, which was done in 1N HCl solution for 10 days. Both weight changes and surface corrosion appearances of specimens for each day were respectively investigated by using electronic weighing machine and SEM(Scanning Electron Microscope). The discoloration degress of TiN-coated specimens immersed in 1N HCl solution were investigated by using color analyzer and then judged by N.B.S.(National Bureau of Standard) Unit. The results of this study were summarized as follows. o TiN ion-plated films showed the hue of 5Y, the value of 7, and the chroma of 3 by Munsell notations. o The weight losses and surface changes of TiN ion-plated specimens immersed in 1N HCl solution were less than those of non ion-plated specimens. It was shown, therefore, that the corrosion resistance was significantly improved by TiN ion-plating. o The discoloration degrees of non ion-plated specimens were too significant to be examined by color analyzer, while those of TiN ion-plated specimens were slight when judged by N.B.S. Unit. It was also apparent, therefore, that the anti-discoloration property was significantly improved by TiN ion-plating.

• Journal of Environmental Science International
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• v.33 no.2
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• pp.169-178
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• 2024

This study aimed to investigate the impact of pavement design changes on user perceptions, with the objective of enhancing safety in urban streetscape. A total of 72 participants were recruited, and the study focused on alleyways in areas with a high risk of crime. Employing the Semantic Differential (SD) methodology, an assessment was conducted to gauge participants' perceptions of three different pavement types (A-type, B-type, C-type) as well as the existing pavement. The results indicated that the C-type pavement, characterized by vibrant and harmonious color palettes and patterns, elicited the highest levels of perceived safety, comfort, and openness among users. This signifies that physical environmental improvements through color design can mitigate the feelings of insecurity and foster emotional stability. Therefore it is recommended to implement various color schemes and pattern designs to road surface for enhancing user safety in high-risk urban areas.

• Journal of Marine Bioscience and Biotechnology
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• v.16 no.1
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• pp.19-25
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• 2024

To verify the color change in dried laver postproduction during the heating process, chromaticity elements were compared via a spectrophotometer across various heating conditions within the visible light spectrum. In general, the moisture reduction rate increased with rising temperature and time. Surface image comparisons revealed an expanded area of light reflection on the heat-treated dried laver sample due to surface roughening from shrinkage. No statistically significant differences in chromaticity values were observed in the measurements of brightness (L^*), redness (a^*), and yellowness (b^*). Reflectance spectrum measurements in the visible light region confirmed high reflectance under red wavelength conditions. In particular, a significant increase in reflectance at 700 nm compared with untreated samples was noted. The correlation between the increase in 700 nm reflectance of dried laver samples and heating conditions ranged from 0.7471 to 0.7793, suggesting its potential use as an indicator for comparing color changes in dried laver based on heating conditions.

• Textile Coloration and Finishing
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• v.34 no.3
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• pp.165-172
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• 2022

Polypropylene(PP) is a textile material with various functions such as eco-friendliness, lightness, and elasticity. Although most synthetic fibers can be dyed and finished, but original PP is difficult to dye or finish due to its extremely hydrophobic properties, so its application expansion is limited. In order to solve this problem, dyeable PP was developed, and various researches on textiles for clothing such as mass production technology, fine fiberization and performance improvement are in progress. Plasma treatment is a processing method for modifying the surface of fabrics, and has effects such as hydrophilization, deepening color, improving adhesion, and surface polymerization. In this study, plasma treatment was applied to study changes in hydrophilization properties of dyeable PP, surface changes before and after plasma treatment and performance according to hydrophilization.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.245-251
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• 2001

This research was conducted to study the changes in physical characteristics of mushrooms (Agaricus bisporus) as influenced by drying methods. Samples were dried using either hot air drying, vacuum drying, or freeze drying and changes in the color, browning index, hardness and rehydration rate were evaluated by response surface methodology. Hot air drying resulted in the fastest drying of sample as compared to other methods. The rate of drying was most affected by the environmental temperature rather than air velocity or vacuum pressure. The overall color difference increased as the temperature and air velocity increased. The overall color changes of the freeze dried samples were minimal as compared to those of fresh mushrooms. The hot air dried samples showed the greatest changes in the overall color, browning index as well as hardness. The freeze dried samples showed the best rehydration characteristic and maintained the best overall quality after drying.

• Fashion & Textile Research Journal
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• v.7 no.5
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• pp.542-546
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• 2005

This study was investigated to establish the optimum conditions of dyeing silk fabric with Brassica campestris. This experiment was done under different dyeing conditions of dye concentration, dyeing temperature, dyeing time, dyeing repeating times, and mordants which were treated pre, syn, and post methods. The effects of dyeing conditions and mordanting were evaluated in terms of dyeaffinity(K/S value) and CIE-Lab color factors. Also, the effect of mordanting on color fastnesses was assessed. The dyeaffinity increased remarkably as dye concentration increased up to 200% owf. The dyeaffinity increased continuously with dyed temperature and reached dyeing equilibrium at $80^{\circ}C$. The maximum dyeaffinity was observed at 30minutes of dyeing time. In the relationship between the K/S value and dyeing repeating times, the K/S value became higher as repeating time was increased. The changes of surface color and colorfatness of dyes were not increased greatly on all mordanting states. The extracts of Brassica campestris produced mainly yellow color in silk fabric. The antimicrobial activity existed slightly as the ratio of 22.7%.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.2
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• pp.155-161
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• 1998

Response surface methodology (RSM) was used for optimizing preparation conditions and monitoring the quality of buckwheat mook prepared using buckwheat starch. The textures(hardness, adhesiveness, cohesiveness and gumminess) of buckwheat mook were decreased in inverse proportion to the increase of water content. the L and b values of Hunter color parameters in buckwheat mook were increased in proportion to the increase of water content. However, The a value of Hunter color parameters of buckwheat mook were decreased in inverse proportion to the increase of water content. Organoleptic properties(color, form, taste and mouth-feel) of buckwheat mook showed a maximum score in 700ml(water content), 14min(gelatinization time)