Color matching and color recovery in large composite restorations using single-shade or universal composites

Abstract This study assessed the color-matching ability and color recovery of unprepared teeth when using single-shade composites and a universal composite in large restorations. Buccal and palatine surface colors of molars were measured with a spectrophotometer (CIELAB) before preparing round cavities (6 mm in diameter, 2 mm in depth). The cavities were randomly filled with a single-shade composite (Omnichroma, Diamond One, or Vittra APS Unique) or a universal composite (Filtek Universal). Color measurements of the restored cavities were taken, and overall color differences (ΔEab and ΔE00) and differences in the whitening index for dentistry (ΔWID) from baseline were calculated. Additionally, visual assessments of a color match to the surrounding enamel were performed by forty evaluators (laypersons and undergraduate students of dentistry) in a viewing booth under illuminant D65, with rating scores from 0 (no color mismatch) to 4 (not acceptable). Data were analyzed using RM or one-way ANOVA (α = 0.05). Results showed that the restorations generally exhibited whiter colors (WID ranged from 27.9 to 41.3) than the unprepared teeth (WID ranged from 15.9 to 19.3). The composite Filtek Universal demonstrated the lowest color discrepancy (ΔWID = 8.6; ΔE00 = 10.8; and ΔE00 = 6.2), and no significant differences were observed among the evaluated single-shade composites. Furthermore, all composites showed similar and adequate color matches to the surrounding enamel. However, it is important to note that despite their ability to match the surrounding enamel reasonably, none of the composites evaluated in large restorations fully recovered the color observed in unprepared teeth.

Resumo Este estudo avaliou a habilidade de combinação de cores e recuperação de cor de dentes não preparados ao utilizar resinas compostas de única tonalidade e uma resina composta universal em grandes restaurações. As cores das superfícies bucais e palatinas de molares foram medidas com um espectrofotômetro (CIELAB) antes de preparar cavidades esféricas (6 mm de diâmetro, 2 mm de profundidade). As cavidades foram preenchidas aleatoriamente com uma resina composta de única tonalidade (Omnichroma, Diamond One ou Vittra APS Unique) ou com uma resina composta universal (Filtek Universal). Foram realizadas medições das cores das cavidades restauradas e calculadas as diferenças de cor globais (ΔEab and ΔE00)) e as diferenças no índice de clareamento para odontologia (ΔWID) em relação à cor inicial. Além disso, foram realizadas avaliações visuais da correspondência de cor com o esmalte circundante por quarenta avaliadores (leigos e estudantes de odontologia) em uma cabine de visualização sob iluminante D65, com pontuações de 0 (nenhuma discrepância de cor) a 4 (não aceitável). Os dados foram analisados usando RM ou ANOVA unidirecional (α = 0,05). Os resultados mostraram que as restaurações geralmente apresentavam cores mais brancas (WID variou de 27,9 a 41,3) do que os dentes não preparados (WID variou de 15,9 a 19,3). A resina composta Filtek Universal demonstrou a menor discrepância de cor (ΔWID = 8,6; ΔE00 = 10,8; and ΔE00 = 6,2), e não foram observadas diferenças significativas entre as resinas compostas de única tonalidade avaliadas. Além disso, todas as resinas compostas apresentaram correspondência de cor similar e adequada com o esmalte circundante. No entanto, é importante observar que, apesar de sua capacidade de corresponder razoavelmente com o esmalte circundante, nenhuma das resinas compostas avaliadas em grandes restaurações recuperou completamente a cor observada nos dentes não preparados.

Application of optical illusion in stomatological aesthetics / 口腔疾病防治

@#Optical illusion refers to the phenomenon in which the scene observed by the human eye is not completely consistent with the objectively presented scene. Optical illusions in stomatology, as well as their clinical application, are demonstrated in this paper in terms of shade, shape and aesthetic design. Shade is not only affected by the optical illusions with which it is associated, such as color metamerism, color constancy and the Chevreul illusion, but also influenced by the surroundings. It is suggested that the surrounding lighting during veneering should be the same as that during color matching in the clinic. As indicated by the Poggendorf illusion and the Leaning Tower illusion, the practice should be conducted and checked from multiple perspectives to compensate for the limitation of human eyes, such as intraoral scanning. Other digital technologies, including digital facial scanning and cephalometric measurement, could be used to reduce the subjective influence of observation. In terms of esthetic design, the interaction of the part and the whole, suggested by Ebbinghaus illusion, should be considered: an individual harmony smile should be designed considering the characteristics of the personality and the features of the face, lips, teeth and gingiva of the patient. Furthermore, personal information, such as gender and age, should be taken into consideration in beautification presentation. Further research should be focused on the influence of optical illusions in stomatology in more details. More communication among doctors, technicians and patients is needed. Clinicians should be aware of the impact of optical illusions to reduce subjective bias in clinical standardized operations and further take advantage of optical illusions to create beautification presentations of dental restorations and smiles.

Effects of Different Drying Methods on the Main Components of Forsythia suspensa Flowers / 中国药房

OBJECTIVE：To establish the method for the content det ermination of 4 components in Forsythia suspensa flowers by drying in shade ，vacuum freeze-drying ，oven（30，50，70 ℃）and sun ，so as to evaluate the effects of different drying methods on the main components of F. suspensa flowers and screen the optimal drying method. METHODS ：UPLC method was adopted. The determination was performed on Waters ACQUITY UPLC BEH C 18 column with mobile phase consisted of acetonitrile- 0.1％ phosphoric acid aqueous solution （gradient elution ）at the flow rate of 0.3 mL/min. The detection wavelength was set at 230 nm， and column was 35 ℃. The sample size was 1 μL. Euclidean closeness（C）i of different drying methods was calculated by TOPSIS comprehensive analysis method ，and the optimal drying method was defined. RESULTS ：The linear range of forsythiaside A ， rutin，forsythin，（+）-pinoresinol-4-O-β-D-glucopyranoside were 0.007 5-0.037 7，0.027 4-0.137 2，0.001 9-0.009 5，0.005 6-0.028 8 µg（all r＞0.999）. RSDs of precision ，stability（32 h）and reproducibility tests were all lower than 2％. The recoveries were 97.27％-102.53％，100.53％-104.11％，98.45％-104.02％，98.66％-104.82％，respectively；and all RSDs ＜3％（n＝3）. The contents were 1.645 8-4.987 9，11.730 2-20.978 0，0.875 5-2.005 0，2.366 0-5.535 7 mg/g. The content of forsythiaside A was the highest after drying at 30 ℃，rutin and （+）-pinoresinol-4- O-β-D-glucopyranoside were the highest after vacuum freeze-drying，forsythiaside was the highest after drying at 50 ℃ . Results of TOPSIS analysis showed that Ci of F. suspensa flowers by drying in shade ，vacuum freeze-drying ，oven（30，50，70 ℃）and sun were 0.079 9，0.553 5，0.495 4， 0.503 8，0.157 9，0.217 2，respectively；the order of Ci was vacuum freeze-drying ＞ 50 ℃ oven drying ＞ 30 ℃ oven drying＞sun drying ＞70 ℃ oven drying ＞ shade drying. CONCLUSIONS：Established method is simple ，reproducible and can be used for the content determination of 4 components in F. suspensa flowers. The samples are preferably dried by vacuum freeze-drying，followed by 50 ℃ oven drying ，30 ℃ oven drying ， and then dried in the sun and oven at 70 ℃ and finally in the shade.

Low-light and its effects on crop yield: Genetic and genomic implications

Shade indicates decreased sunlight. The agricultural importance of shade imparts to its deteriorative effect of cropyield. Rice is not only the most widely used food crop by a third of the population of the world, but it has also beenestablished as the model monocot plant for study. This article describes several important aspects of shade on rice yieldwith appropriate examples in other plants such as Arabidopsis. To start with, how different environmental or growthconditions create shade is explained. The morphological, physiological and biochemical characteristics due to differentkinds of shade are selectively explained. The molecular characteristics of rice under shade from genetic, genomic andepigenetic studied are discussed. Signalling components for the manifestation of shade tolerance responses and theirinterconnection with other signalling networks and hormone pathway components are from recent reports. A list ofgenes, micro-RNAs and metabolites that are involved in shade responses is presented. Lastly, implications forsustainable yield under shade is discussed. This review will be useful not only for cutting-edge information on shadetolerance but will also build framework for upcoming new rice varieties with sustainable yield under shade.

Effects of shade on guinea grass genotypes Megathyrsus maximus (Poales: Poaceae)

Introduction: Light stress is an important factor limiting the biomass yield while combining forage production with crops or forestry. Guinea grass is a widely adapted perennial fodder grass. The species exhibits high degree of variation for morphology, adaptation and biomass yield. Objective: Since there is a need in identifying shade adapted forage grasses for the expanding area under agroforestry/silvipastures, the present investigation took the task of understanding how the morphologically distinct genotypes of guinea grass respond under different shaded intensities. Methods: In the present study, forty-four genotypes related with the shade response were studied in varying shading conditions (pure sunlight, 25, 50 and 75 % shade) created artificially. Results: Based on green and dry matter yields ranking, the genotype IG 01-98 performed the best followed by genotypes IG 01-92, IG 97-5, IG 97-6 and IG 01-89 in decreasing order. Particularly, IG 01-93 was identified as the best performing under 50 % shading conditions. On the other hand, most of the top ranking genotypes performed well both under open and up to 50 % of shade. Morphologically, these genotypes were taller and possessed longer and broader leaves. Under shaded conditions (over 50 %), leaf length and width showed an increasing trend compared to open conditions. Also, chlorophyll content increased with shading intensity. Conclusions: Most of the genotypes collected from the southern Indian humid tropical environment with early flowering nature were tolerant to shade. Differential genotypic response was observed for biomass yield and yield attributes under shade. The study established appreciable variability for shade tolerance among genotypes.

Introducción: El estrés leve es un factor importante que limita el rendimiento de la biomasa al tiempo que combina laproducción forrajera con los cultivos o la silvicultura. El zacate guinea es una planta de forraje perenne ampliamente adaptada. La especie presenta un alto grado de variación en su morfología, adaptación y rendimiento de biomasa. Objetivo: Como existe la necesidad de la identificación de pastos forrajeros adaptados a la sombra para el área de expansión bajo agroforestería /silvicultura, la presente investigación se realizó para entender cómo los genotipos morfológicamente distintos al zacate guinea responden a diferentes intensidades de sombra. Métodos: Se estudiaron 44 genotipos y su respuesta a los niveles de sombra: luz solar pura y 25, 50 y 75 % de sombra (creados artificialmente). Resultados: Basado en la clasificación de rendimientos demateria verde y seca, el genotipo IG 01-98 fue el mejor, seguido de los genotipos IG 01-92, IG 97-5, IG 97-6 e IG 01-89 en orden decreciente. Por su parte, el IG 01-93 fue identificado como el de mayor rendimiento bajo el 50 % de condición de sombra. La mayoría de los genotipos de primer nivel tuvieron un buen desempeño, tanto bajo sombra abierta como al 50 %. Morfológicamente, estos genotipos fueron más altos y poseían hojas más largas y más anchas. En condiciones de sombra, de más del 50 %, la longitud y ancho de la hoja mostraron una tendencia creciente en comparación con la condición abierta. El contenido de clorofila aumentó con la intensidad de la sombra. Conclusiones: La mayoría de los genotipos recolectados al sur de la India en un ambiente tropical húmedo y tienen una floración temprana, fueron tolerantes a la sombra. Se observó una respuesta genotípica diferencial para los atributos de rendimiento y rendimiento de biomasa bajo sombra. El estudio mostró la existencia de una variabilidad apreciable para la tolerancia a la sombra entre los genotipos.

BBX transcriptional factors family in plants-a review / 生物工程学报

Transcriptional factors play important roles in plant growth, development and responses to stresses. BBX transcriptional factors are characterized with one or two B-box domains in the protein sequence. They are comprehensively involved in photomorphogenesis, flowering, shade avoidance, signal transduction of phytohormones, biotic and abiotic stress responses in plants by regulating gene transcription and interacting with other transcription factors. The classification, structure and functions of BBX of plants are reviewed in this paper.

Study of masking ability of laminate veneers for discolored teeth / 北京大学学报(医学版)

OBJECTIVE@#To select the most effective method among different masking treatments, such as different thickness and transparence, tissue surface's opaque coating, and opaque resin cement to restore discolored teeth esthetically by porcelain veneer.@*METHODS@#Four extracted intact maxillary central incisors were prepared for porcelain veneer restoration and each three heat pressed porcelain veneers from three thicknesses (0.8 mm, 1.0 mm, 1.2 mm) and two transparency(high transparence, HT and low transparence, LT))in Vita shade A2 were fabricated for each tooth, in total of 72 pieces. The surfaces of three prepared teeth were then painted to mimic situations of severe dental fluorosis, severe tetracycline teeth, and necrotic teeth. Each of the veneers was temporarily cemented to the corresponding tooth surface using try-in cements with three different colors (transparent, opaque, and yellow), then used the shade guide (3D master) and electronic colorimeter (easy shade) to record the shade of each porcelain veneer through hue, lightness, and chroma reading. After that, high-transparence porcelain veneers in thickness of 0.8 mm was fused with a layer of opaque porcelain in tissue surface, and were shade matched again after cementation. Statistic treatments were performed to analyze the difference in each masking method.@*RESULTS@#For each 0.2 mm increase in the veneer thickness of porcelain, the average lightness was reduced by 1 unit, while the chroma was not changed which was independent of the type of the resin cements. When the thickness of the porcelain veneer was decreased to 0.8 mm, the opacity effect was not remarkable even if a low-transparence porcelain veneer was used. Transparent and yellow resin cements had poor opaque performance, while opaque resin cement could reduce the lightness by 2 units and the chroma was also reduced. The opaque layer of the tissue surface could be applied uniformly, and the lightness and chroma could be reduced to Vita 2M1 to 2M1.5 levels regardless of the color of resin cements, which suggested a stable opacity effect for different discolored teeth in this study.@*CONCLUSION@#For porcelain veneer restoration of discolored teeth, thickened veneers are the most effective means to display a natural transmittance and color. Tissue surface's opacity coatings and opaque resin cements can also be used to reduce grayscale and increase lightness.

Clinical Performance of Direct Anterior Composite Restorations Using Esthetic Dual-Shade versus Polychromatic Natural Layering Technique: a split mouth randomized controlled clinical tria / Avaliação clínica do comportamento de desgaste do esmalte humano e lascamento da zircônia de cobrimento contra a zircônia monolítica (ensaio clínico randomizado controlado)

Objective: to evaluate the clinical performance of the dual shade layering and polychromatic resin composite layering techniques using a randomized controlled trail. Material and Methods: 42 participants (84 restorations) of class IV or class III through and through within a pair of anterior contra-lateral teeth were randomly allocated into two groups according to technique of composite restoration placement: control "polychromatic layering" and intervention "dual-shade layering". Follow-up was done at 1 month (baseline) and 1 year. Restorations were evaluated using Visual Analog Scale (VAS), restoration color shade match using Vita Easyshade V ®, and blinded assessor using FDI criteria for assessment of dental restorations measuring (aesthetic properties). Chi-square test was used to compare between restorations of both techniques. Results: There was no statistically significant difference between restorations of both techniques for patient satisfaction outcome, restorations color match outcome, and for all tested FDI outcomes except surface luster with 100% success. Conclusion: Bothdual-shade layering and polychromatic natural layering techniques, exhibited acceptable clinical and esthetic performance (AU)

Objetivo: Avaliar o comportamento de desgaste do esmalte humano e lascamento de zircônia de cobrimento e monolítica para restaurações posteriores de cobertura total. Material e métodos: Trinta e quatro restaurações de zircônia de cobertura total (dezessete em cada grupo) foram fabricadas. Os pacientes foram divididos em dois grupos de acordo com o tipo de zircônia utilizada; grupo 1 (grupo comparador) coroas com zircônia de cobrimento e grupo 2 (grupo de intervenção) coroas únicas de zircônia monolítica. Todas as coroas foram fabricadas e polidas em laboratório. Para medidas de desgaste de dentes opostos, foi utilizado um perfilômetro 3D sem contato, onde réplicas de resina epóxi foram construídas para o arco oposto imediatamente após a cimentação das coroas, três, seis e doze meses. O lascamento da restauração foi medido usando critérios modificados dos Serviços de Saúde Pública dos Estados Unidos (USPHS). Resultados: Todas as restaurações foram relatadas como alfa sem lascamento. Não houve diferença estatisticamente significativa entre (Grupo 1) e (Grupo 2) para o teste de desgaste. Conclusão: As restaurações monolíticas e de cobrimento revelaram propriedades mecânicas satisfatórias sem lascamento após um ano de uso clínico. O desgaste do esmalte oposto foi clinicamente aceitável para ambos os materiais (AU)

Shade tolerance within the context of the successional process in tropical rain forests

Shade tolerance (the capacity to survive and grow over long periods under shade) is a key component of plant fitness and the foundation of current theories of forest succession in tropical rain forests. It serves as a paradigm to understand the optimal allocation of limited resources under dynamic light regimes. I analyze how tropical rain forest succession influences the expression of ecophysiological mechanisms leading to shade tolerance, and identify future areas that will increase our understanding of the ecological and evolutionary consequences of this phenomenon. Shade tolerance is a multivariate, continuous functional trait reflecting the growth-mortality trade-off of investing resources under limited light vs. exploiting high light conditions. I propose the life cycle successional trajectory model of Gómez-Pompa & Vázquez-Yanes as an integrative tool to understand tropical rain forest succession. This model shows how species distribute along the successional environmental gradient based on their degree of shade tolerance and represents a more integrative paradigm to understand the interface between different aspects of species diversity (ontogenetic variation and functional diversity) throughout succession. It proposes that different trait combinations determining shade tolerance are expressed at different stages of the life cycle, which affects how and when plants enter the successional trajectory. Models explaining the expression of shade tolerance (resource availability, carbon gain, CSR, resource competition) are based on whole-plant economics and are not mutually exclusive. The analysis of shade tolerance is biased towards tree seedlings in the understory of mature forests. Other life stages (juvenile and adult trees), life forms, and microhabitats throughout the forest profile are almost always excluded from these analyses. More integrative explanations based on the distribution of functional traits among species, ontogenetic stages, and the nature of the environmental gradient are being developed based on long-term data and chronosequence comparisons. In summary, shade-tolerance is a complex phenomenon, is determined by multiple characters that change ontogenetically over space and time and entails considerable plasticity. Current methods do not account for this plasticity. Understanding the nature of shade tolerance and its functional basis is critical to comprehending plant performance and improving the management, restoration and conservation of tropical rain forests given the combined threats of global warming and habitat loss.

La tolerancia a la sombra (la capacidad de sobrevivir y crecer durante largos períodos bajo sombra profunda) es un componente clave del valor adaptativo de la planta y la base de las teorías actuales de la sucesión forestal de la selva tropical. Sirve como un paradigma para entender la asignación óptima de recursos limitados bajo regímenes dinámicos de luz. En esta revisión analizo cómo la sucesión de los bosques tropicales lluviosos influye en la expresión de los mecanismos ecofisiológicos que conducen a la tolerancia a la sombra, e identifico áreas futuras que pueden aumentar nuestra comprensión de las consecuencias ecológicas y evolutivas de este fenómeno. La tolerancia a la sombra es un rasgo funcional continuo y multivariable que refleja el balance de invertir recursos bajo condiciones de luz limitada versus crecer más rápidamente en condiciones de luz intensa. Propongo el modelo de ciclo de vida a lo largo de la trayectoria de sucesión de Gómez-Pompa y Vázquez-Yanes como una herramienta integradora para entender la sucesión de la selva tropical. Este modelo muestra cómo las especies se distribuyen a lo largo del gradiente ambiental en función de su grado de tolerancia a la sombra, y representa un paradigma más integrador para comprender la interacción entre los diferentes componentes de la diversidad de especies (diversidad taxonómica y funcional y variación ontogenética) a lo largo de la sucesión. El modelo propone que las diferentes combinaciones de caracteres funcionales que determinan la tolerancia a la sombra se expresan en diferentes etapas del ciclo de vida, y afectan cómo y cuándo las plantas ingresan en el proceso de sucesión. Los modelos que explican la expresión de tolerancia a la sombra (disponibilidad de recursos, ganancia de carbono, CSR, competencia de recursos) se basan en la economía de toda la planta y no son mutuamente excluyentes. Se están desarrollando explicaciones más integradoras basadas en la distribución de caracteres funcionales entre especies, etapas ontogenéticas, y micrositios, mediante el uso de estudios de cronosecuencia y metadatos colectados a largo plazo. El análisis de la tolerancia a la sombra está sesgado hacia las plántulas de árboles y el sotobosque. Otras formas de vida y microhábitats dentro del perfil del bosque están casi excluidas de estos análisis. En resumen, la tolerancia a la sombra es un fenómeno complejo, está determinada por múltiples caracteres funcionales que cambian ontogenéticamente en el espacio y el tiempo, e implica una considerable plasticidad. Los métodos actuales no toman en cuenta esta plasticidad. Comprender la naturaleza de la tolerancia a la sombra y su base funcional es fundamental para entender el crecimiento de la planta y mejorar la gestión, restauración, y conservación de los bosques tropicales, los cuales enfrentan las amenazas combinadas del calentamiento global y la pérdida de hábitat.

Proposal for a gingival shade guide based on in vivo spectrophotometric measurements

PURPOSE: The purpose of this study was to propose and assess a shade guide for pink gingival aesthetics using a Spanish population sample. MATERIALS AND METHODS: The L*, C*, h, a* and b* coordinates of 259 participants were measured using a spectrophotometer in 3 standardized points along the attached gingiva of the maxillary central incisors. A hierarchical clustering analysis was applied to obtain separate solutions regarding the number of shade tabs. For each of the solutions obtained, color differences (ΔE*) were calculated using the CIELab and CIEDE2000 formulas, and the proposed shade guide was selected considering (1) the color differences between tabs and (2) the coverage error of each of the solutions. RESULTS: The proposed shade guide consisted of 8 gingival shade tabs and achieved CIELab and CIEDE2000 coverage errors of less than the respective 50:50% acceptability thresholds (ΔE*=4.6 units and ΔE₀₀=4.1). The coordinates for the various gingival shade tabs were as follows: Tab 1: L*43.3, a*21.9, b*12.3 (1.6); Tab 2: L*42.9, a*34.1, b*19.1; Tab 3: L*46.5, a*25.8, b*10.9; Tab 4: L*46.5, a*27.3, b*15.1; Tab 5: L*49.6, a*23.5, b*16.8; Tab 6: L*51.5, a*19.7, b*13.6; Tab 7: L*55.9, a*22.0, b* 15.0; and Tab 8: L*56.0, a*19.9, b*18.8. CONCLUSION: The CIELab and CIEDE2000 coverage errors for the 8 shade tabs of the proposed gingival shade guide were significantly lower than those of other guides. Therefore, despite the limitations of this study, the proposed guide is more appropriate for matching gingival shade in the Spanish general population.

Effects of different drying methods on appearance and internal components of Notoginseng Radix et Rhizoma / 中草药

Objective: The effects of different drying methods (drying-in-the-shade, sun-drying, freeze-drying and hot air drying) on the appearance traits, internal structure and quality of the main roots of Notoginseng Radix et Rhizoma (NRR) were revealed, which provided a theoretical basis for screening the drying methods suitable for the primary processing of NRR. Methods: In this study, the effect of four different drying methods on drying rate, rehydration rate, appearance traits, alcohol extracts and internal components (dencichine, saponin component notoginsenoside R1 and ginsenoside Rg1, Rb1, Rd, Re, and reducing sugar, total sugar) of NRR were compared. Results: Fresh NRR was dried by drying-in-the-shade method, and the drying rate was slow, which took about 473 h. However, the appearance quality of the medicinal materials was excellent with firm texture, slow rehydration rate, and high content of total saponins and dencichine. The drying rate of materials under sun drying method was also slow, and due to the long drying cycle, the starch and sugar of the medicinal materials were more decomposed, resulting in the whitening part of the medicinal materials of NRR. When fresh NRR was dried by hot air, the drying rate was faster and the time was shortened. When the temperature was 40 ℃, the appearance of the medicine was not much different from that of the drying-in-the-shade method. After drying, the material was firmer, except for the content of dencichine, the content of saponin had no difference between that of drying-in-the-shade; Due to the high drying temperature at 50 ℃ and 60 ℃, the excessive dehydration rate led to the hollowness of the NRR, and medicinal material was not solid; The rehydration rate was fast, and the content of NRR spilled out, resulting in sugar coking, and the color of the cross section of the medicinal material changed into deeper with the increase of the drying temperature, which resulted in the decomposition of starch, and the significant increase of total sugar and reducing sugar content. The lyophilized medicinal material had a very fast rehydration rate, and the internal texture was loose and porous, and the texture became light, but the saponin component and dencichine were the highest active ingredients. Conclusion: Considering the aspects of appearance, medicinal ingredients and cost, fresh NRR dried by drying-in-the-shade method obtained solid material, compacted internal structure, good appearance and high content of medicinal ingredients. The primary processing method of NRR should be drying-in-the-shade. If the processing volume of the medicinal material is large, it needs to shorten the drying time, and the primary processing method of NRR should be hot air drying process at about 40 ℃. If the high-content medicinal ingredients are the purpose, it is recommended to use freeze-drying.

Impacto de la luz operatoria sobre las resinas compuestas: evaluación de su contracción / The impact of operative light on composite resins: evaluation of their shrinkage

El objetivo de este estudio fue analizar el comportamiento, contracción volumétrica, de diferentes resinas compuestas de fotopolimerización, expuestas a variadas condiciones de incidencia lumínica. Se tomaron volúmenes estandarizados de 7 resinas compuestas (microhíbridas y nanohíbridas y nanoparticulados) que se colocaron sobre una línea de referencia en portaobjetos, cubriéndose luego con otro y aplicando una fuerza previamente establecida. Se midió luego con un calibre electrónico la variaciones en el diámetro de la muestra bajo tres situaciones diferentes: luz ambiente (natural), luz foco (halógena), luz artificial (tubos fluorescentes) y sus combinaciones. Resultados: Se observó la mayor variación porcentual al exponer a las muestras simultáneamente a la luz ambiente, artificial y operatoria, siendo los valores más altos de reducción para las resinas compuestas Brilliant NG Coltene (Dentina) y Miris 2 Coltene (Dentina) con -2.52% y -2.7% respectivamente. Conclusión: existieron modificaciones en el volumen de todos los materiales expuestos a las diferentes condiciones de luz y tiempo de exposición. Comparando los resultados con el estudio previo (2007) se pude inferir que los materiales usados en el presente estudio resultaron más fotosensibles, dado que a similar exposición, aumentaron y/redujeron su tamaño en mayor medida (AU)

Spatial distribution of dairy heifers' dung in silvopastoral systems / Distribuição espacial de fezes de novilhas leiteiras em sistemas silvipastoris

ABSTRACT: Ruminants vary their walking trajectory according to the positioning of the trees in integrated systems, which can determine the concentration of dung deposition at certain locations. The aim of this study was to map the distribution of feces and the behavior of dairy heifers in sunny and shaded areas. This experiment was carried out in Mato Grosso, Brazil, where the main grazing conditioner is shade due to the presence of trees in the pastures. Shading levels used were: full sunlight (control), moderate shade (338 trees ha−1) and intensive shade (714 trees ha−1) in randomized complete blocks. The experimental period was divided into three evaluation periods based on rainfall distribution: rainy period = December 2012; transition period = March 2013 and dry period = June 2013. Animal behavior assessments and dung distribution mapping were performed. The full sunlight system displayed a higher concentration of feces patches at sites near the gate, cow drinkers and fences opposite the gate. Heifers picked shaded places for ruminating and idleness. The major concentration was reported in the central area and under trees, in shaded systems. There were places with greater feces concentrations, but when the pasture had trees, deposition did not only happen underneath trees but also in places under their influence. The distribution was more homogeneous when trees were present in large quantities. The shaded area available in pastures affects spatial distribution of dung, stimulating uniformity.

RESUMO: Os ruminantes variam a trajetória de sua caminhada de acordo com o posicionamento das árvores em sistemas integrados. A deposição de fezes pode estar mais ou menos concentrada em determinados locais, de acordo com a disposição desses condicionadores de pastejo que definem o caminhamento animal. O objetivo deste experimento foi mapear a localização e a distribuição de fezes de bezerras leiteiras de acordo com seu comportamento afetado pela disponibilidade de áreas ensolaradas e sombreadas. Este experimento foi conduzido em Mato Grosso, no Brasil. O principal condicionador de pastejo foi o sombreamento promovido pela presença de árvores nas pastagens. Foram impostos níveis de sombreamento: pleno sol (controle), sombreamento moderado (338 árvores ha− 1) e sombreamento intenso (714 árvores ha− 1) em blocos completos casualizados. O período experimental foi dividido em períodos de avaliação com base na distribuição das chuvas: Período Chuvoso = dezembro de 2012; Período de Transição = Março de 2013 e Período Seco = Junho de 2013. Foram realizadas avaliações de comportamento animal e mapeamento da distribuição das placas de fezes na área. Para atividades de ruminação e lazer, as novilhas preferiram os locais mais sombreados. O sistema pleno sol promoveu maior concentração de placas de fezes em locais próximos a porteiras e bebedouros, no lado oposto ao da porteira. Nos sistemas sombreados, a maior concentração foi na área central e sob sombra. Havia locais com maior concentração de fezes, mas quando havia árvore na pastagem, a deposição não acontecia apenas abaixo da árvore, mas também nos locais sob sua influência. A distribuição foi mais homogênea quando as árvores estavam em maiores quantidades. A área de sombra disponível no pasto afeta a distribuição espacial do esterco estimulando a uniformidade.

Clinical evaluation of color change and tooth sensitivity with in-office and home bleaching treatments

Among the number of vital bleaching techniques currently available to the clinicians, home bleaching and in-office bleaching are widely used in dental practice. Aim and Objectives: The aim of this in vivo study was to compare the clinical performance, durability, and related tooth sensitivity with two vital bleaching procedures (in-office and at-home bleaching), in a split-mouth design. Patients and Methods: Thirty adult participants having teeth shade mean of A2 or darker were selected for the study. One-half of the maxillary arch of each patient received in-office bleaching with 35% hydrogen peroxide gel, and the other half received 16% carbamide peroxide night guard bleaching. Shade evaluation was done with shade guide and spectrophotometer at 1, 2, 3, and 4 week intervals during bleaching and postoperatively at 3 and 6 month intervals. Tooth sensitivity was recorded using the visual analog scale during the experimental period. Statistical Analysis: Collected data of color and sensitivity readings were subjected to statistical analysis using SPSS/PC version 20 software. Intergroup comparison through unpaired t-test and within the groups using paired t-test was done. Results: At-home and in-office bleaching procedures are equally effective in producing tooth whitening. Color evaluation after 3 and 6 months showed more color decline for in-office bleaching procedure. For sensitivity parameter also, in-office procedure recorded higher sensitivity compared to home bleaching (P < 0.05). Conclusion: Both the bleaching procedures are equally effective in producing tooth whitening. In-office bleaching recorded higher levels of tooth sensitivity and greater color rebound than home bleaching.

Leaf architecture and symmetry of understory tree species of anAraucaria forest / Arquitetura foliar e simetria de espécies do sub-bosque da floresta com Araucária

Shade plants of ombrophilous forests are subjected to light-limiting conditions and need toinvest in architectural structures associated with leaf symmetry to increase light capture. This study investigated the leaf architecture of six Araucaria forest tree species with distinct symmetry: Cupania vernalis, Casearia sylvestris, Schinus terebinthifolius, Piper gaudichaudianum, Roupala brasiliensis and Cedrela fissilis. We hypothesized that symmetry, associated with other traits, minimizes self-shading. Asymmetry index, petiole length, total leaf area, leaf angle, internode length and stem diameter were measured. The asymmetry index did not indicate a clear distinction between asymmetric and symmetric leaves. Leaves classified as asymmetric had higher values for the asymmetry index in the median and basal regions of the leaf, while symmetrical leaves had higher values in the apical region. The results also indicated an adjustment among structural leaf traits that facilitated a three-dimensional organization that produced an advantageous arrangement for light capture, which seems to be a response to selective pressure by the heterogeneous light conditions of the ombrophilous forest understory.

Nas florestas ombrófilas, as plantas de sombra estão sujeitas a condições limitantes de luz enecessitam investir em atributos estruturais associados à simetria foliar para maximizar a captura da luz. Esse estudo investigou a arquitetura foliar de seis espécies arbóreas (Cupania vernalis, Casearia sylvestris, Schinus terebinthifolius, Piper gaudichaudianum, Roupala brasiliensis e Cedrela fissilis) da Floresta com Araucária. Nossa hipótese é que a simetria foliar, associada a outros atributos foliares, minimiza o autosombreamento. Foram mensurados o índice de assimetria, o comprimento do pecíolo, a área foliar total, ângulo foliar, o comprimento do internó e o diâmetro do caule. O índice de assimetria não indicou uma distinção clara entre folhas assimétricas e simétricas. Folhas classificadas como assimétricas apresentaram maior índice na região mediana e basal da folha, enquanto as folhas simétricas apresentaram maior índice na região apical. Os resultados também indicaram um ajuste entre os atributos estruturais que permitiram um arranjo tridimensional das folhas vantajoso para a captura de luz, o que parece ser uma resposta à pressão seletiva pelas condições heterogêneas de luz do sub-bosque de floresta ombrófila.

Influence of the microwave sintering period on the 3 point flexural strength and shade of zirconia restoration / 대한치과재료학회지

In this study, we tried to confirm clinically applicable applicability by comparing the difference in 3 point flexural strength and shade of the prosthesis depending on microwave sintering time of dental CAD / CAM zirconia. 3 Point flexural strength specimens (n=30) and shade measurement specimens (n=28) were prepared and sintered at different sintering times. 3 point flexural strength and shade were measured and analyzed by independent t-test (α=0.05). Measurement result of 3 point flexural strength the average of short-term sintering (STS) was 245.47±29.89 MPa, the average of long-term sintering (LTS) was 284.27±31.56 MPa, and there was a statistically significant difference (p 0.05). The 3 point flexural strength of the zirconia restorations fabricated by short time and long time was high in long time sintering. However, other conditions may be required for clinical applications. Since the shade test did not show any significant color difference according to sintering time, it is considered to be sufficient for clinical application.

Correlation analysis between cold and heat property of traditional Chinese medicines and light conditions of their original plants in habitat / 中国中药杂志

The current study was conducted to explore the relationship between property of traditional Chinese medicines (TCM) and the light conditions of their original plant in habitats and advance a "light-cold and heat property" hypothesis under the guidance of theory of TCM. In the present study, we selected 127 common Chinese herbs. Association rules mining method was used to find out the association relationship between the cold-heat properties of different TCM and the habitats of their original plant, while using statistical methods to analyze the correlation between light condition and cold-heat property of TCM based on the description of the habitats in the Flora of China and investigation. The results showed that the habitats associated to TCM with cold property are in the order of grassland>curb>hillside>wasteland>gully>farmland>riverside. The habitats that associated to TCM with heat property are: undergrowth>shrub>gully>jungle. For 68 TCMs with cold property, 81.2% of their original plants are light-demanding, 8.7% are shade-demanding, and 8.7% of them showed no obvious light preference. For 59 TCMs with heat property, 62.7% of their original plants are shade-demanding, 20.3% are shade-demanding, and 17.0% of them showed no obvious light preference. Meanwhile, Chi-square test showed that there was a significant difference between the cold-heat property and light preference (<0.01). In summary, there is a significant correlation between the light preference of TCM original plants and their cold-heat properties. In order to ensure the pharmacological effect of TCM, the relationship between the light conditions and the properties of TCM should be considered in the cultivation of medicinal plants for TCM.

Effects of clonal integration on the proximal and distal ramets of Cynodon dactylon under shade stress

ABSTRACT In a pot experiment, clonal ramets of Cynodon dactylon, a stolon herbaceous plant, were treated with heterogeneous lighting. Proximal ramets (elder ramets) were subjected to shade stress at three different degrees, and stolons between proximal and distal ramets of each pair were treated in a connected or severed manner. Results showed that in moderate shade stress, the number of ramets and leaves, biomass, net photosynthetic rate (Pn), maximum quantum yield (Fv/Fm), effective quantum yield of PSII (ФPSII), and soil and plant analysis development values (SPAD) of proximal ramets were significantly reduced, regardless of whether stolons were kept intact or severed. However, the growth of distal ramets was not significantly influenced, and keeping the stolons intact also did not bring apparent benefits for the whole clonal fragments. These results show that clonal integration does not help alleviate the shade stress suffered by proximal ramets and the costs of distal ramets and does not significantly influence the whole clonal fragments. The possible reasons are that distal ramets may be at the cost of metabolism for resource transportation when the proximal ramets suffer from shade stress; thus, clonal integration is not favorable.

Comparative study on the shade matching performance of dental students under D55 and D65 light sources conditions / 华西口腔医学杂志

OBJECTIVE@#This study aimed to compare the effect of D55 and D65 light sources on the visual colorimetry performance of dental students by using a homemade light-source shelf.@*METHODS@#Two Vitapan 3D-Master shade guides were randomly selected. One set was used as shade guides. Ten commonly used shade tabs of 2L2.5, 2M2, 2R2.5, 3M2, 3R2.5, 3L1.5, 3R1.5, 3L2.5, 4R1.5, and 4L1.5 were selected from the other set with covered value marks and numbered from 1 to 10. After the colorimetric training, 49 undergraduate dental students were randomly divided into two groups. Each student randomly selected two of the 10 shade tabs, and the colors were subsequently matched under D65 and D55 light sources from a distance of approximately 40 cm. The average color difference (ΔE) between the color selected by each participant and the actual color of shade tabs was calculated. Paired t test was used for statistical analysis.@*RESULTS@#The ΔE values between the color selected by each participant and the actual color of the shade tabs under the D55 light source varied from 0 to 6.540. The average value was 2.501. The ΔE values between the color selected by each participant and the actual color of the shade tabs under the D65 light source varied from 0 to 6.610. The average value was 2.530. No statistically significant difference was observed between the results under the two light sources (P=0.921).@*CONCLUSIONS@#Both D55 and D65 daylight lamps can be used for daily dental colorimetry. These two different color temperatures showed no significant difference.

The effects of shade and light irradiation on the polymerization of composite resin core materials / 实用口腔医学杂志

Objective:To evaluate the effects of shade and light irradiation condition on the polymerization of composite resin core material.Methods:The light-proof silicon rubber cuboid mold with one end open were stringed and filled by dual-cured flowable composite resin core material with the shade of dentine and white(Paracore) respectively,then the open end of mold was irradiated directly by a light unit at 1 000 mW/cm2 ×20 s and 3 200 mW/cm2 ×6 s respectively.And all specimens of 4 groups(n =5) were stored in the light-proof box.1 h and 24 h after irradiation,Knoop microhardness was measured along the vertical surfaces of the specimens at the depth of 1,2 and 3 mm respectively.Data were analyzed by One-way ANOVA.Results:At all light irradiation conditions,the hardness of all specimens decreased with the increase of measurement depth.24 h after irradiation,the hardness of dentine shade specimens at each measurement depth showed no difference between 1 000 mW/cm2 × 20 s and 3 200 mW/cm2 × 6 s irradiation,while the white shade specimens irradiated by 1 000 mW/cm2 × 20 s showed higher hardness than those by 3 200 mW/cm2 × 6 s.Conclusion:To obtain sufficient polymerization of composite core material with different shade optimal light irradiation condition should be selected.