• Title/Summary/Keyword: Shade

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The influence of shade allocation or total shade plus overhead fan on growth performance, efficiency of dietary energy utilization, and carcass characteristics of feedlot cattle under tropical ambient conditions

  • Castro-Perez, Beatriz I.;Estrada-Angulo, Alfredo;Rios-Rincon, Francisco G.;Nunez-Benitez, Victor H.;Rivera-Mendez, Carlos R.;Urias-Estrada, Jesus D.;Zinn, Richard A.;Barreras, Alberto;Plascencia, Alejandro
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.6
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    • pp.1034-1041
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    • 2020
  • Objective: The objective of this experiment was to evaluate the effect of shade allocation and shade plus fan on growth performance, dietary energy utilization and carcass characteristics of feedlot cattle under tropical ambient conditions Methods: Two trials were conducted, involving a total of 1,560 young bulls (289±22 kg BW) assigned to 24 pens (65 bulls/pen and 6 pens/treatment). Pens were 585 ㎡ with 15 m fence line feed bunks. Shade treatments (㎡ shade/animal) were: i) limited shade (LS) to 1.2 ㎡ shade/animal (LS1.2); ii) limited shade to 2.4 ㎡ shade/animal (LS2.4); iii) total shade (TS) which correspond to 9 ㎡/animal, and iv) total shade equipped with fans (TS+F). Trials lasted 158 and 183 days. In both studies, the average weekly maximum temperature exceeded 34℃. Results: Increasing shade allocation tended (p = 0.08) to linearly increases average daily gain (ADG), and dry matter intake (DMI, quadratic effect, p = 0.03). This effect was most apparent between LS1.2 and LS2.4. Shade allocation, per se, did not affect gain efficiency or estimated dietary net energy (NE). Compared with TS, TS+F increased (p<0.05) ADG, gain efficiency, and tended (p = 0.06) to increase dietary NE. There was a quadratic effect of shade on longissimus area and marbling score, with values being lower (p<0.01) for LS2.4 than for LS1.2 or TS. Likewise, marbling score was lower for TS+F than for TS. Percentage kidney, pelvic, and heart (KPH) linearly decreased with increasing shade. In contrast, KPH was greater for TS than for TS+F. Conclusion: Providing more than 2.4 ㎡ shade/animal will not further enhance feedlot performance. The use of fans in combination with shade increases ADG and gain efficiency beyond that of shade, alone. These enhancements were not associated with increased DMI, but rather, to an amelioration of ambient temperature humidity index on maintenance energy requirement.

A Spectrophotometric Study on Color Differences between Various Light-Cured Composite Resins and Shade Guides (광중합형 복합레진과 shade guide의 색차에 관한 연구)

  • Lim, Kyung-Min;Lee, Min-Ho;Song, Kwang-Yeob
    • Journal of Dental Rehabilitation and Applied Science
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    • v.25 no.1
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    • pp.13-22
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    • 2009
  • The composite resin, due to its esthetic quality, is considered the material of choice for restoration of anterior teeth. To get a satisfactory result in the composite resin restorations, it is necessary to choose right shade. At present, most of the commercial composite resins are based on the Vita Lumin shade guides or shade guides that are provided by their company, but color differences among them might be expected even using the same shade in various materials. This study is to measure color differences between various light-cured composite resins and shade guides and to provide the clinicians with information which may aid in improved color match of esthetic restoration. Four kinds of light-cured composite resins (Gradia Direct (GD), Z250 (Z250), Clearfil AP-X (AP-X), Esthet X (E X)) and shade guides with A2 and A3 shade were used. Three specimens of each material and one specimen of each shade guide were made. Each composite resin was filled into the Teflon mold (1.35 mm depth, 8 mm diameter), followed by compression, polymerization and polishing with wet sandpaper. Shade guides were grinded with polishing stones and rubber points to a thickness of approximately 1.35 mm. Color characteristics were performed with a spectrophotometer(color i5, GretagMacbeth, USA). A computer-controlled spectrophotometer was used to determine CIELAB coordinates ($L^*$, $a^*$, $b^*$) of each specimen and shade guide. The CIELAB measurements made it possible to evaluate the amount of the color difference values (${\Delta}E^*ab$) between composite resins and shade guides. CIE standard D65 was used as the light source. The results were as follows : 1. Among the $L^*$, $a^*$, $b^*$ values of most of 4 kinds of composite resin specimens which are produced by same shade, there were significant differences(p<0.05). 2. Among all 4 kinds of composite resin specimens which are produced by same shade, there were color differences that is perceptible to human eye(${\Delta}E^*>3.3$). 3. Between most of composite resin specimens investigated and their corresponding shade guides, there were color differences that is perceptible to human eye(${\Delta}E^*>3.3$). 4. In the clinical environment, it is recommended that custom shade guides be made from resin material itself for better color matching. Shade guides supplied by manufacturers or Vita Lumin shade guide may not provide clinicians a accurate standard in matching color of composite resins, and there are perceptible color differences in most of products. Therefore, it is recommended that custom shade guides be made from resin material itself and used for better color matching.

Comparison of different digital shade selection methodologies in terms of accuracy

  • Nursen Sahin;Cagri Ural
    • The Journal of Advanced Prosthodontics
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    • v.16 no.1
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    • pp.38-47
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    • 2024
  • PURPOSE. This study aims to evaluate the accuracy of different shade selection techniques and determine the matching success of crown restorations fabricated using digital shade selection techniques. MATERIALS AND METHODS. Teeth numbers 11 and 21 were prepared on a typodont model. For the #11 tooth, six different crowns were fabricated with randomly selected colors and set as the target crowns. The following four test groups were established: Group C, where the visual shade selection was performed using the Vita 3D Master Shade Guide and the group served as the control; Group Ph, where the shade selection was performed under the guidance of dental photography; Group S, where the shade selection was performed by measuring the target tooth color using a spectrophotometer; and Group I, where the shade selection was performed by scanning the test specimens and target crowns using an intraoral scanner. Based on the test groups, 24 crowns were fabricated using different shade selection techniques. The ΔE values were calculated according to the CIEDE2000 (2:1:1) formula. The collected data were analyzed by means of a one-way analysis of variance. RESULTS. For the four test groups (Groups C, Ph, S, and I), the following mean ΔE values were obtained: 2.74, 3.62, 2.13, and 3.5, respectively. No significant differences were found among the test groups. CONCLUSION. Although there was no statistically significant difference among the shade selection techniques, Group S had relatively lower ΔE values. Moreover, according to the test results, the spectrophotometer shade selection technique may provide more successful clinical results.

A Study on Color Differences Between Composite Resins and Shade Guides (복합레진과 shade guide의 색차에 관한 연구)

  • Kim, Hee-Sun;Um, Chung-Moon;Kahng, Myong-Whai
    • Restorative Dentistry and Endodontics
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    • v.21 no.1
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    • pp.107-120
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    • 1996
  • 복합레진은 조작이 용이하고 강도가 우수하며 중합시간이 짧고 법랑질과 상아질에 접착이 가능하며 연마성이 뛰어나고 자연스러운 색상을 나타내므로 심미적 수복에 가장 일반적으로 선택되는 재료의 하나이다. 대부분의 복합레진 kit에는 shade guide가 포함되어 있어 이를 기준으로 중합된 후의 복합레진 색조를 예상하여 선택하게 된다. 그러나 이러한 shade guide들은 대개 복합레진이 아닌 plastic으로 제조된 것으로 중합된 복합레진의 실제 색조와는 차이가 생기게 되며 결국 shade guide 자체의 문제점으로 인해 이상적인 색조선택이 어려워진다. 이에 본 연구에서는 국내에 시판되고 있는 5종의 복합레진 제품을 선정하여 분광 광도계를 이용해서 shade guide와 중합된 복합레진 사이의 색조차이를 측정, 비교 연구하였다. 직경 16mm. 두께 1.6mm의 plastic mold에 5종의 광중합형 복합레진(Z100, Prisma TPH, Tetric, Silux Plus, Herculite XR)을 충전하고 응축기에 넣어 압축한 후 제조사의 지시에 따라 광중합기로 중합시킨 후 mold에서 시편을 제거하여 보관했다가 젖은 sandpaper 상에서 순차적으로 연마하였다. shade guide는 step부분을 갈아내어 복합레진 시편과 동일한 두께로 만든후 연마하였다. 분광광도계에 shade guide를 넣고 CIE illuminant D65 하에서 spectral reflectance를 측정하고 해당 색조의 복합레진 시편도 통일한 방법으로 측정하고 $L^*$, $a^*$, $b^*$값과 ${\Delta}E^*$값을 얻은후 분석하여 다음과 같은 결과를 얻었다. 1. Z100의 D3, A3, B2 shade와 Prisma TPH의 B2 shade를 제외한 모든 시편에서 shade guide와 복합레진간에 육안으로 인지할 수 있는 색차(${\Delta}E^*$ > 1.0)가 관찰되었다. 2. 평균적으로 Z100이 가장 적은 색차를 나타내었고 Prisma TPH, Tetric, Silux Plus, Herculite XR 순으로 색차가 증가하였다. 3. Prisma TPH의 A2 shade. Tetric의 W shade. Silux Plus의 YB, U shade, Herculite XR의 L, LY shade는 ${\Delta}E^*$값이 3.3 이상으로 나타났다. 4. Z100, Prisma TPH, Tetric, Silux Plus에서는 복합레진보다 shade guide가 더 높은 $L^*$값을 보이는 경향이 나타났으며, Herculite XR에서만 복합레진이 더 높은 $L^*$값을 나타냈다. 5. 모든 시편에서 $b^*$ 값은 (+)로 관찰되었고, Z100, Prisma TPH, Tetric, Silux Plus의 shade guide는 복합레진에 비해 높은 $b^*$값을 보였다. 6. 모든 시편에서 $a^*$값은 (-)로 관찰되었고. Herculite XR 및 Silux Plus에서는 복합레진이 shade guide 에 비 해 낮은 $a^*$값을 나타냈다.

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Effect of Shade Net on Reduction of Freezing Damage at a Tea Garden (차밭에 설치된 차광망의 동해경감 효과)

  • Hwang, Jung-Gyu;Kim, Yong-Duck
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.16 no.2
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    • pp.146-154
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    • 2014
  • In the result of effect on freezing damage reduction by the shade net colors and the shade rate to tea trees during wintering period, the high shade ratio decreased tea trees growth and increased freezing damage and 55% of shade ratio based on non treatment developed new leafs and green leaf productivity. By the shade net colors, colorless shade net (55% of shade type) treatment and green shade net treatment increased green leaf productivity and decreased damaged area compare to non treatment shade net and black shade net treatment. Colorless net shade treatment reduced over 50% of freezing damage and increased (10a) 68 kg for green leaf productivity compare to non treatment shade net. The colors of shade net treatments for reduction freezing damaged in order of Black < Green < Colorless but reduction of freezing damage was so high. In the relative microclimates, treatment shade nets were $0.7^{\circ}C$ lower, average relatively humidity 14.9% higher, soil temperature $0.6^{\circ}C$ lower and soil moisture 4.6% higher than non treatment shade net. And treatment shade nets decreased average wind speed 0.7 m/s and it showed us treatment net shades effected to excessive evapotranspiration and soil dry by wind and considered one of good solution for freezing damages.

Colorimetric Analysis of Preformed Zirconia Anterior Crowns for Esthetic Restoration (심미수복용 기성 지르코니아 크라운의 색조 평가)

  • Lee, Changkeun;Park, Kibong;Yang, Yeonmi;Lee, Daewoo;Kim, Jaegon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.46 no.3
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    • pp.318-327
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    • 2019
  • The purpose of this study was to identify which combination of zirconia crowns and cements is most similar in color to the maxillary primary incisors by varying the color of zirconia crowns, crown thickness, and shade of cements. Prefabricated zirconia crowns in 3 shades and crowns fabricated using 6 types of zirconia blocks were used in this study. These were filled with A2-shade or translucent-shade resin cement and the $L^*$, $a^*$, and $b^*$ values were calculated using a spectrophotometer. The color differences between the natural teeth and the zirconia crowns were assessed. The shade of the final restoration was more similar to that of the natural teeth using A2-shade than translucent-shade resin cement. Application of A2-shade cement to a 0.5-mm-thick crown fabricated from a smile series 2 zirconia block resulted in the color most similar to that of the natural teeth. A2-shade resin cement is recommended for zirconia crown restoration in anterior primary teeth compared to TR-shade resin cement for more esthetic restoration. Since restorations with Nu-smile zirconia crowns were not esthetically favorable in terms of shade, improvement of the shade characteristics of the product or development of a new kind of zirconia crown is required.

Assessment of microclimate conditions under artificial shades in a ginseng field

  • Lee, Kyu Jong;Lee, Byun-Woo;Kang, Je Yong;Lee, Dong Yun;Jang, Soo Won;Kim, Kwang Soo
    • Journal of Ginseng Research
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    • v.40 no.1
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    • pp.90-96
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    • 2016
  • Background: Knowledge on microclimate conditions under artificial shades in a ginseng field would facilitate climate-aware management of ginseng production. Methods: Weather data were measured under the shade and outside the shade at two fields located in Gochang-gun and Jeongeup-si, Korea, in 2011 and 2012 seasons to assess temperature and humidity conditions under the shade. An empirical approach was developed and validated for the estimation of leaf wetness duration (LWD) using weather measurements outside the shade as inputs to the model. Results: Air temperature and relative humidity were similar between under the shade and outside the shade. For example, temperature conditions favorable for ginseng growth, e.g., between $8^{\circ}C$ and $27^{\circ}C$, occurred slightly less frequently in hours during night times under the shade (91%) than outside (92%). Humidity conditions favorable for development of a foliar disease, e.g., relative humidity > 70%, occurred slightly more frequently under the shade (84%) than outside (82%). Effectiveness of correction schemes to an empirical LWD model differed by rainfall conditions for the estimation of LWD under the shade using weather measurements outside the shade as inputs to the model. During dew eligible days, a correction scheme to an empirical LWD model was slightly effective (10%) in reducing estimation errors under the shade. However, another correction approach during rainfall eligible days reduced errors of LWD estimation by 17%. Conclusion: Weather measurements outside the shade and LWD estimates derived from these measurements would be useful as inputs for decision support systems to predict ginseng growth and disease development.

Comparison on accuracy of porcelain color reproducibility using two colorimeters (2종의 측색기에 의한 도재 색조 재현의 정확성 비교)

  • Lee, Tai-Il;Ahn, Jin-Soo;Kim, Young-Soo;Shin, Sang-Wan
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.3
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    • pp.348-355
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    • 2009
  • Statement of problem: Although the use of colorimeter to improve the accuracy of tooth color measurement has increased, it is real situation that there is almost no comparative study about the accuracy among various colorimeters. Purpose: The purpose of this study is to compare the accuracy of porcelain color reproducibility using ShadeEye-Ncc dental chroma meter (Shofu Inc., Kyoto, Japan) and Shadepilot$^{TM}$ system (Degudent Inc., Hanau, Germany). Material and methods: Color of 2M2 and 3M2 shade tap of Vitapan 3D Master shade guide were measured using the above two colorimeters. Porcelain specimens were fabricated through this data. The porcelain systems used were Vintage Halo Porcelain system with ShadeEye-Ncc dental chroma meter, and VitaOmega900 Porcelain system with Shadepilot$^{TM}$ system. Colors of shade tap models and porcelain specimen were measured with spectrophotometer, and calculated delta E based on the results. Results: The following results were obtained. 1. Shadepilot$^{TM}$ system showed more suitable porcelain color reproducibility compared to ShadeEye-Ncc dental chroma meter (P <.05). 2. The result showed the difference of porcelain color reproducibility according to shade of Shade tap which is model. More suitable porcelain color reproducibility was shown at 3M2 shade tap than at 2M2 shade tap (P <.05). 3. The average of ${\Delta}E*$ of porcelain specimens which was made by the two colorimeters was 4.44-6.14, so the difference of shade was shown through the naked eye. Conclusion: Shadepilot$^{TM}$ system showed more suitable porcelain color reproducibility. When using ShadeEye-Ncc dental chromameter, it will be necessary to improve accuracy through coloring various parts of the whole tooth.

Clinical Color Match using ShadepilotTM (ShadepilotTM을 이용한 색조 선택)

  • Shin, Soo-Yeon
    • Journal of Dental Rehabilitation and Applied Science
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    • v.23 no.3
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    • pp.219-225
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    • 2007
  • The ability of a dentist to select and communicate an acceptable shade match to a dental laboratory may be the most important factor in esthetic restorative dentistry. However, shade matching is a very complex situation. In this study, an attempt was made to compare and evaluate the conventional visual assessment and colorimetric analysis in clinical shade matching. 20 patients were selected and their maxillary central incisors shade were measured by Vita classic shade guide, using $Shadepilot^{TM}$ and ShadeEye $NCC^{(R)}$. The results indicate that there is much variation in the shade selection by visual and instrumental methods.

Clinical Color Match using ShadepilotTM (ShadepilotTM을 이용한 색조 선택)

  • Shin, Soo-yeon
    • Journal of Dental Rehabilitation and Applied Science
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    • v.23 no.2
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    • pp.131-137
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    • 2007
  • The ability of a dentist to select and communicate an acceptable shade match to a dental laboratory may be the most important factor in esthetic restorative dentistry. However, shade matching is a very complex situation. In this study, an attempt was made to compare and evaluate the conventional visual assessment and colorimetric analysis in clinical shade matching. 20 patients were selected and their maxillary central incisors shade were measured by Vita classic shade guide, using $Shadepilot^{TM}$ and ShadeEye $NCC^{(R)}$. The results indicate that there is much variation in the shade selection by visual and instrumental methods.