WorldWideScience

Sample records for varying shade tolerance

  1. Microclimatological and Physiological Controls of Stomatal Conductance and Transpiration of Co-Occurring Seedlings with Varying Shade Tolerance

    Science.gov (United States)

    Siegert, C. M.; Levia, D. F.

    2010-12-01

    Forest ecosystems provide a significant portion of fresh water to the hydrologic cycle through transpiration, the majority of which is supplied by saplings and mature trees. However, a smaller, yet measurable, proportion is also supplied by seedlings. The contribution of seedlings is dependent upon physiological characteristics of the species, whose range of habitat is ultimately controlled by microclimate. The objectives of this study were to (1) observe meteorological conditions of two forest microlimates and (2) assess the intra- and interspecific stomatal conductance and transpiration responses of naturally occurring seedlings of varying shade tolerance. Naturally established seedlings in a deciduous forest understory and an adjacent clearing were monitored throughout the 2008 growing season in southeastern Pennsylvania (39°49'N, 75°43'W). Clear spatial and temporal trends of stomatal conductance and transpiration were observed throughout this study. The understory microclimate conditions overall had a lower degree of variability and had consistently lower mean quantum flux density, air temperature, vapor pressure deficit, volumetric water content, and soil temperature than the clearing plot. Shade tolerant understory seedlings (Fagus grandifolia Ehrh. (American beech) and Prunus serotina L. (black cherry)) had significantly lower mean monthly rates of water loss (p = 0.05) than shade intolerant clearing seedlings (P. serotina and Liriodendron tulipifera L. (yellow poplar)). Additionally, water loss by shade grown P. serotina was significantly lower (p = 0.05) than by sun grown P. serotina. Significant intraspecific responses (p = 0.05) were also observed on a monthly basis, with the exception of L. tulipifera. These findings indicate that physiological differences, specifically shade tolerance, play an important role in determining rates of stomatal conductance and transpiration in tree seedlings. To a lesser degree, microclimate variability was also shown

  2. Plasticity in seedling morphology, biomass allocation and physiology among ten temperate tree species in response to shade is related to shade tolerance and not leaf habit.

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    Chmura, D J; Modrzyński, J; Chmielarz, P; Tjoelker, M G

    2017-03-01

    Mechanisms of shade tolerance in tree seedlings, and thus growth in shade, may differ by leaf habit and vary with ontogeny following seed germination. To examine early responses of seedlings to shade in relation to morphological, physiological and biomass allocation traits, we compared seedlings of 10 temperate species, varying in their leaf habit (broadleaved versus needle-leaved) and observed tolerance to shade, when growing in two contrasting light treatments - open (about 20% of full sunlight) and shade (about 5% of full sunlight). We analyzed biomass allocation and its response to shade using allometric relationships. We also measured leaf gas exchange rates and leaf N in the two light treatments. Compared to the open treatment, shading significantly increased traits typically associated with high relative growth rate (RGR) - leaf area ratio (LAR), specific leaf area (SLA), and allocation of biomass into leaves, and reduced seedling mass and allocation to roots, and net assimilation rate (NAR). Interestingly, RGR was not affected by light treatment, likely because of morphological and physiological adjustments in shaded plants that offset reductions of in situ net assimilation of carbon in shade. Leaf area-based rates of light-saturated leaf gas exchange differed among species groups, but not between light treatments, as leaf N concentration increased in concert with increased SLA in shade. We found little evidence to support the hypothesis of a increased plasticity of broadleaved species compared to needle-leaved conifers in response to shade. However, an expectation of higher plasticity in shade-intolerant species than in shade-tolerant ones, and in leaf and plant morphology than in biomass allocation was supported across species of contrasting leaf habit. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  3. Shade tolerance of selected afforestation species on Loess Plateau, China

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    Naijiang Wang; Yong Wang; Callie J. Schweitzer

    2011-01-01

    To select tree and vegetation species for afforestation on Loess Plateau of China, we tested the shade tolerance of nine tree and one vine species. We planted 3-year-old seedlings in the greenhouse of the Seedling Nursery at Northwest Agriculture and Forest University in China.

  4. An appraisal of the classic forest succession paradigm with the shade tolerance index

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    Jean Lienard; Ionut Florescu; Nikolay. Strigul

    2015-01-01

    We revisit the classic theory of forest succession that relates shade tolerance and species replacement and assess its validity to understand patch-mosaic patterns of forested ecosystems of the USA. We introduce a macroscopic parameter called the “shade tolerance index” and compare it to the classic continuum index in southern Wisconsin forests. We exemplify shade...

  5. Leaf traits show different relationships with shade tolerance in moist versus dry tropical forests

    NARCIS (Netherlands)

    Poorter, L.

    2009-01-01

    ¿ Shade tolerance is the central paradigm for understanding forest succession and dynamics, but there is considerable debate as to what the salient features of shade tolerance are, whether adult leaves show similar shade adaptations to seedling leaves, and whether the same leaf adaptations are found

  6. A Novel Two-Step Method for Screening Shade Tolerant Mutant Plants via Dwarfism

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    Li, Wei; Katin-Grazzini, Lorenzo; Krishnan, Sanalkumar; Thammina, Chandra; El-Tanbouly, Rania; Yer, Huseyin; Merewitz, Emily; Guillard, Karl; Inguagiato, John; McAvoy, Richard J.; Liu, Zongrang; Li, Yi

    2016-01-01

    When subjected to shade, plants undergo rapid shoot elongation, which often makes them more prone to disease and mechanical damage. Shade-tolerant plants can be difficult to breed; however, they offer a substantial benefit over other varieties in low-light areas. Although perennial ryegrass (Lolium perenne L.) is a popular species of turf grasses because of their good appearance and fast establishment, the plant normally does not perform well under shade conditions. It has been reported that, in turfgrass, induced dwarfism can enhance shade tolerance. Here we describe a two-step procedure for isolating shade tolerant mutants of perennial ryegrass by first screening for dominant dwarf mutants, and then screening dwarf plants for shade tolerance. The two-step screening process to isolate shade tolerant mutants can be done efficiently with limited space at early seedling stages, which enables quick and efficient isolation of shade tolerant mutants, and thus facilitates development of shade tolerant new cultivars of turfgrasses. Using the method, we isolated 136 dwarf mutants from 300,000 mutagenized seeds, with 65 being shade tolerant (0.022%). When screened directly for shade tolerance, we recovered only four mutants from a population of 150,000 (0.003%) mutagenized seeds. One shade tolerant mutant, shadow-1, was characterized in detail. In addition to dwarfism, shadow-1 and its sexual progeny displayed high degrees of tolerance to both natural and artificial shade. We showed that endogenous gibberellin (GA) content in shadow-1 was higher than wild-type controls, and shadow-1 was also partially GA insensitive. Our novel, simple and effective two-step screening method should be applicable to breeding shade tolerant cultivars of turfgrasses, ground covers, and other economically important crop plants that can be used under canopies of existing vegetation to increase productivity per unit area of land. PMID:27752260

  7. A novel two-step method for screening shade tolerant mutant plants via dwarfism

    Directory of Open Access Journals (Sweden)

    Wei Li

    2016-10-01

    Full Text Available When subjected to shade, plants undergo rapid shoot elongation, which often makes them more prone to disease and mechanical damage. Shade-tolerant plants can be difficult to breed; however, they offer a substantial benefit over other varieties in low-light areas. Although perennial ryegrass (Lolium perenne L. is a popular species of turf grasses because of their good appearance and fast establishment, the plant normally does not perform well under shade conditions. It has been reported that, in turfgrass, induced dwarfism can enhance shade tolerance. Here we describe a two-step procedure for isolating shade tolerant mutants of perennial ryegrass by first screening for dominant dwarf mutants, and then screening dwarf plants for shade tolerance. The two-step screening process to isolate shade tolerant mutants can be done efficiently with limited space at early seedling stages, which enables quick and efficient isolation of shade tolerant mutants, and thus facilitates development of shade tolerant new cultivars of turfgrasses. Using the method, we isolated 136 dwarf mutants from 300,000 mutagenized seeds, with 65 being shade tolerant (0.022%. When screened directly for shade tolerance, we recovered only four mutants from a population of 150,000 (0.003% mutagenized seeds. One shade tolerant mutant, shadow-1, was characterized in detail. In addition to dwarfism, shadow-1 and its sexual progeny displayed high degrees of tolerance to both natural and artificial shade. We showed that endogenous gibberellin (GA content in shadow-1 was higher than wild-type controls, and shadow-1 was also partially GA insensitive. Our novel, simple and effective two-step screening method should be applicable to breeding shade tolerant cultivars of turfgrasses, ground covers, and other economically important crop plants that can be used under canopies of existing vegetation to increase productivity per unit area of land.

  8. Seedling growth and biomass allocation in relation to leaf habit and shade tolerance among 10 temperate tree species.

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    Modrzyński, Jerzy; Chmura, Daniel J; Tjoelker, Mark G

    2015-08-01

    Initial growth of germinated seeds is an important life history stage, critical for establishment and succession in forests. Important questions remain regarding the differences among species in early growth potential arising from shade tolerance. In addition, the role of leaf habit in shaping relationships underlying shade tolerance-related differences in seedling growth remains unresolved. In this study we examined variation in morphological and physiological traits among seedlings of 10 forest tree species of the European temperate zone varying in shade tolerance and leaf habit (broadleaved winter-deciduous species vs needle-leaved conifers) during a 10-week period. Seeds were germinated and grown in a controlled environment simulating an intermediate forest understory light environment to resolve species differences in initial growth and biomass allocation. In the high-resource experimental conditions during the study, seedlings increased biomass allocation to roots at the cost of leaf biomass independent of shade tolerance and leaf habit. Strong correlations between relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf area (SLA) and leaf mass fraction (LMF) indicate that physiology and biomass allocation were equally important determinants of RGR as plant structure and leaf morphology among these species. Our findings highlight the importance of seed mass- and seed size-related root morphology (specific root length-SRL) for shade tolerance during early ontogeny. Leaf and plant morphology (SLA, LAR) were more successful in explaining variation among species due to leaf habit than shade tolerance. In both broadleaves and conifers, shade-tolerant species had lower SRL and greater allocation of biomass to stems (stem mass fraction). Light-seeded shade-intolerant species with greater SRL had greater RGR in both leaf habit groups. However, the greatest plant mass was accumulated in the group of heavy-seeded shade-tolerant

  9. Morphological and Physiological Characteristics of Shading Tolerant and Sensitive Mungbean Genotypes

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    TITIK SUNDARI

    2009-12-01

    Full Text Available Study of morphological and physiological characteristics of the tolerant and sensitive mungbean genotypes to shading was carried out in the Station Research of the Indonesian Legume and Tuber Crops Research Institute (ILETRI from September to December 2004. Nine tolerant genotypes (MMC 87 D-KP-2, MLG 369, MLG 310, MLG 424, MLG 336, MLG 428, MLG 237, MLG 429, and VC2768B and three sensitive genotypes to shading (Nuri, MLG 460, and MLG 330 were tested in two shading levels, that were without shading and shading of 52%. The randomized complete block design with three replications analysis. The results showed that leaf characters of shading tolerant and sensitive genotypes were different. The shading tolerant mungbean genotypes had good response to light stress so that the growth and development of the leaves were better than that of sensitive genotypes. The shading tolerant mungbean genotypes had bigger and thicker leaves than that of sensitive genotypes. The shading treatments caused reducing rate of PAR absorption, transpiration, photosynthesis, and CO2 stomata conductance. The reduction of all parameters in tolerant genotype was smaller than that of sensitive genotype. The specific leaf area at four weeks after planting could be used as shading tolerant indicator of mungbeans.

  10. Evaluating relationships among tree growth rate, shade tolerance, and browse tolerance following disturbance in an eastern deciduous forest

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    Lisa M. Krueger; Chris J. Peterson; Alejandro Royo; Walter P. Carson

    2009-01-01

    Interspecific differences in shade tolerance among woody species are considered a primary driving force underlying forest succession. However, variation in shade tolerance may be only one of many interspecific differences that cause species turnover. For example, tree species may differ in their sensitivity to herbivory. Nonetheless,...

  11. Wood density and its radial variation in six canopy tree species differing in shade-tolerance in western Thailand

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    Nock, Charles A.; Geihofer, Daniela; Grabner, Michael; Baker, Patrick J.; Bunyavejchewin, Sarayudh; Hietz, Peter

    2009-01-01

    Background and Aims Wood density is a key variable for understanding life history strategies in tropical trees. Differences in wood density and its radial variation were related to the shade-tolerance of six canopy tree species in seasonally dry tropical forest in Thailand. In addition, using tree ring measurements, the influence of tree size, age and annual increment on radial density gradients was analysed. Methods Wood density was determined from tree cores using X-ray densitometry. X-ray films were digitized and images were measured, resulting in a continuous density profile for each sample. Mixed models were then developed to analyse differences in average wood density and in radial gradients in density among the six tree species, as well as the effects of tree age, size and annual increment on radial increases in Melia azedarach. Key Results Average wood density generally reflected differences in shade-tolerance, varying by nearly a factor of two. Radial gradients occurred in all species, ranging from an increase of (approx. 70%) in the shade-intolerant Melia azedarach to a decrease of approx. 13% in the shade-tolerant Neolitsea obtusifolia, but the slopes of radial gradients were generally unrelated to shade-tolerance. For Melia azedarach, radial increases were most-parsimoniously explained by log-transformed tree age and annual increment rather than by tree size. Conclusions The results indicate that average wood density generally reflects differences in shade-tolerance in seasonally dry tropical forests; however, inferences based on wood density alone are potentially misleading for species with complex life histories. In addition, the findings suggest that a ‘whole-tree’ view of life history and biomechanics is important for understanding patterns of radial variation in wood density. Finally, accounting for wood density gradients is likely to improve the accuracy of estimates of stem biomass and carbon in tropical trees. PMID:19454592

  12. Salinity tolerance of 'Valencia' orange trees on rootstocks with contrasting salt tolerance is not improved by moderate shade.

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    García-Sánchez, F; Syvertsen, J P; Martínez, V; Melgar, J C

    2006-01-01

    The effects of shading in combination with salinity treatments were studied in citrus trees on two rootstocks with contrasting salt tolerance to determine if shading could reduce the negative effects of salinity stress. Well-nourished 2-year-old 'Valencia' orange trees grafted on Cleopatra mandarin (Cleo, relatively salt tolerant) or Carrizo citrange (Carr, relatively salt sensitive), were grown either under a 50% shade cloth or left unshaded in full sunlight. Half the trees received no salinity treatment and half were salinized with 50 mM Cl- during two 9 week salinity periods in the spring and autumn interrupted by an 11 week rainy period. The shade treatment reduced midday leaf temperature and leaf-to-air vapour pressure deficit regardless of salinity treatments. In non-salinized trees, shade increased midday CO2 assimilation rate (A(CO2)) and stomatal conductance, but had no effect on leaf transpiration (E(lf)). Shade also increased leaf chlorophyll and photosynthetic water use efficiency (A(CO2)/E(lf)) in leaves on both rootstocks and increased total plant dry weight in Cleo. The salinity treatment reduced leaf growth and leaf gas exchange parameters. Shade decreased Cl- concentrations in leaves of salinized Carr trees, but had no effect on leaf or root Cl- of trees on Cleo. There were no significant differences in leaf gas exchange parameters of shaded and unshaded salinized plants but the growth reduction from salinity stress was actually greater for shaded than for unshaded trees. Shaded trees on both rootstocks had higher leaf Na+ than unshaded trees after the first salinity period, and this shade-induced elevated leaf Na+ persisted after the second salinity period in trees on Carr. Thus, shading did not alleviate the negative effects of salinity on growth and Na+ accumulation.

  13. Herbivory on temperate rainforest seedlings in sun and shade: resistance, tolerance and habitat distribution.

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    Cristian Salgado-Luarte

    Full Text Available Differential herbivory and/or differential plant resistance or tolerance in sun and shade environments may influence plant distribution along the light gradient. Embothrium coccineum is one of the few light-demanding tree species in the temperate rainforest of southern South America, and seedlings are frequently attacked by insects and snails. Herbivory may contribute to the exclusion of E. coccineum from the shade if 1 herbivory pressure is greater in the shade, which in turn can result from shade plants being less resistant or from habitat preferences of herbivores, and/or 2 consequences of damage are more detrimental in the shade, i.e., shade plants are less tolerant. We tested this in a field study with naturally established seedlings in treefall gaps (sun and forest understory (shade in a temperate rainforest of southern Chile. Seedlings growing in the sun sustained nearly 40% more herbivore damage and displayed half of the specific leaf area than those growing in the shade. A palatability test showed that a generalist snail consumed ten times more leaf area when fed on shade leaves compared to sun leaves, i.e., plant resistance was greater in sun-grown seedlings. Herbivore abundance (total biomass was two-fold greater in treefall gaps compared to the forest understory. Undamaged seedlings survived better and showed a slightly higher growth rate in the sun. Whereas simulated herbivory in the shade decreased seedling survival and growth by 34% and 19%, respectively, damaged and undamaged seedlings showed similar survival and growth in the sun. Leaf tissue lost to herbivores in the shade appears to be too expensive to replace under the limiting light conditions of forest understory. Following evaluations of herbivore abundance and plant resistance and tolerance in contrasting light environments, we have shown how herbivory on a light-demanding tree species may contribute to its exclusion from shade sites. Thus, in the shaded forest understory

  14. Size-symmetric competition in a shade-tolerant invasive plant

    DEFF Research Database (Denmark)

    Pan, Xiao-Yun; Weiner, Jacob; Li, Bo

    2013-01-01

    Plant responses to crowding have been investigated extensively in stands of light‐demanding species, but shade‐tolerant species may react differently. In the present study, we investigated the effect of density on the mortality, size inequality, and biomass allocation of Alternanthera philoxeroid...... that are shade tolerant, cooperative, and follow a relatively fixed allometric trajectory with low plasticity....

  15. Light-related variation in sapling architecture of three shade-tolerant tree species of the Mexican rain forest

    NARCIS (Netherlands)

    Martinez-Sanchez, J.L.; Meave, J.; Bongers, F.

    2008-01-01

    The crown architecture of three shade-tolerant tree species (two subcanopy and one mid-canopy) was analyzed in relation to the light regime of the forest understorey. The aim was to examine to which extent shade-tolerant species variate in their crown architecture. Tree saplings (265) between 50 and

  16. Explaining interspecific differences in sapling growth and shade tolerance in temperate forests

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    Janse-ten Klooster, S.H.; Thomas, E.J.P.; Sterck, F.J.

    2007-01-01

    1. Species differences in growth and shade tolerance might contribute to coexistence of tree species. To explore how such differences depend on underlying plant traits, 14 tree species were investigated in temperate forests on sand and loess soils in the Netherlands. Plant traits were measured for

  17. The effect of irradiance on the carbon balance and tissue characteristics of five herbaceous species differing in shade-tolerance

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    Pons, Thijs L.; Poorter, Hendrik

    2014-01-01

    The carbon balance is defined here as the partitioning of daily whole-plant gross CO2 assimilation (A) in C available for growth and C required for respiration (R). A scales positively with growth irradiance and there is evidence for an irradiance dependence of R as well. Here we ask if R as a fraction of A is also irradiance dependent, whether there are systematic differences in C-balance between shade-tolerant and shade-intolerant species, and what the causes could be. Growth, gas exchange, chemical composition and leaf structure were analyzed for two shade-tolerant and three shade-intolerant herbaceous species that were hydroponically grown in a growth room at five irradiances from 20 μmol m−2 s−1 (1.2 mol m−2 day−1) to 500 μmol m−2 s−1 (30 mol m−2 day−1). Growth analysis showed little difference between species in unit leaf rate (dry mass increase per unit leaf area) at low irradiance, but lower rates for the shade-tolerant species at high irradiance, mainly as a result of their lower light-saturated rate of photosynthesis. This resulted in lower relative growth rates in these conditions. Daily whole-plant R scaled with A in a very tight manner, giving a remarkably constant R/A ratio of around 0.3 for all but the lowest irradiance. Although some shade-intolerant species showed tendencies toward a higher R/A and inefficiencies in terms of carbon and nitrogen investment in their leaves, no conclusive evidence was found for systematic differences in C-balance between the shade-tolerant and intolerant species at the lowest irradiance. Leaf tissue of the shade-tolerant species was characterized by high dry matter percentages, C-concentration and construction costs, which could be associated with a better defense in shade environments where leaf longevity matters. We conclude that shade-intolerant species have a competitive advantage at high irradiance due to superior potential growth rates, but that shade-tolerance is not necessarily associated

  18. An individual-based forest model links canopy dynamics and shade tolerances along a soil moisture gradient.

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    Liénard, Jean; Strigul, Nikolay

    2016-02-01

    Understanding how forested ecosystems respond to climatic changes is a challenging problem as forest self-organization occurs simultaneously across multiple scales. Here, we explore the hypothesis that soil water availability shapes above-ground competition and gap dynamics, and ultimately alters the dominance of shade tolerant and intolerant species along the moisture gradient. We adapt a spatially explicit individual-based model with simultaneous crown and root competitions. Simulations show that the transition from xeric to mesic soils is accompanied by an increase in shade-tolerant species similar to the patterns documented in the North American forests. This transition is accompanied by a change from water to sunlight competitions, and happens at three successive stages: (i) mostly water-limited parkland, (ii) simultaneously water- and sunlight-limited closed canopy forests featuring a very sparse understory, and (iii) mostly sunlight-limited forests with a populated understory. This pattern is caused by contrasting successional dynamics that favour either shade-tolerant or shade-intolerant species, depending on soil moisture and understory density. This work demonstrates that forest patterns along environmental gradients can emerge from spatial competition without physiological trade-offs between shade and growth tolerance. Mechanistic understanding of population processes involved in the forest-parkland-desert transition will improve our ability to explain species distributions and predict forest responses to climatic changes.

  19. Light and competition gradients fail to explain the coexistence of shade-tolerant Fagus sylvatica and shade-intermediate Quercus petraea seedlings.

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    Van Couwenberghe, Rosalinde; Gégout, Jean-Claude; Lacombe, Eric; Collet, Catherine

    2013-11-01

    The coexistence of forest tree species has often been linked to differences among species in terms of their response to light availability during the regeneration stage. From this perspective, species coexistence results from growth-growth or mortality-growth trade-offs along spatial light gradients. Experimental evidence of growth-growth trade-offs in natural conditions is sparse due to various confounding factors that potentially hinder the relationship. This study examined growth hierarchies along light gradients between two tree species with contrasting shade tolerance by controlling potential confounding factors such as seedling size, seedling status, seedling density and species composition. Natural regenerated shade-tolerant Fagus sylvatica and shade-intermediate Quercus petraea seedlings were used, and growth rankings over a 4-year period were compared in 8- to 10-year-old tree seedlings. No rank reversal occurs between the two species along the light gradient, or along the density, mixture or seedling size gradients. The shade-tolerant species was always the more competitive of the two. Pronounced effects of initial size on seedling growth were observed, whereas the effects of light and competition by neighbours were of secondary importance. The paramount effect of size, which results from the asymmetric nature of interseedling competition, gives a strong advantage to tall seedlings over the long term. This study extends previous efforts to identify potential drivers of rank reversals in young tree mixtures. It does not support the classical assumption that spatial heterogeneity in canopy opening explains the coexistence of the two species studied. It suggests that spatial variation in local size hierarchies among seedlings that may be caused by seedling emergence time or seedling initial performance is the main driver of the dynamics of these mixed stands.

  20. Hydraulics and life history of tropical dry forest tree species: coordination of species' drought and shade tolerance

    NARCIS (Netherlands)

    Markesteijn, L.; Poorter, L.; Bongers, F.; Paz, H.; Sack, L.

    2011-01-01

    Plant hydraulic architecture has been studied extensively, yet we know little about how hydraulic properties relate to species’ life history strategies, such as drought and shade tolerance. The prevailing theories seem contradictory. We measured the sapwood (Ks) and leaf (Kl) hydraulic

  1. Ranking the shade tolerance of forty-five candidate groundcovers for agroforestry plantings

    Science.gov (United States)

    J.W. Van Sambeek; N.E. Navarrete-Tindall; H.E. Garrett; C.-H. Lin; R.L. McGraw; D.C. Wallace

    2007-01-01

    Several large-scale screening trials evaluating native and introduced herbaceous ground covers have been conducted in the last half century. Most trials have used shade cloth to evaluate growth of potted plants under moderate shade (45 to 55 percent of full sunlight) similar to what might be found in many agroforestry practices and heavy shade (20 to 30 percent of full...

  2. Tolerable Time-Varying Overflow on Grass-Covered Slopes

    Directory of Open Access Journals (Sweden)

    Steven A. Hughes

    2015-03-01

    Full Text Available Engineers require estimates of tolerable overtopping limits for grass-covered levees, dikes, and embankments that might experience steady overflow. Realistic tolerance estimates can be used for both resilient design and risk assessment. A simple framework is developed for estimating tolerable overtopping on grass-covered slopes caused by slowly-varying (in time overtopping discharge (e.g., events like storm surges or river flood waves. The framework adapts the well-known Hewlett curves of tolerable limiting velocity as a function of overflow duration. It has been hypothesized that the form of the Hewlett curves suggests that the grass erosion process is governed by the flow work on the slope above a critical threshold velocity (referred to as excess work, and the tolerable erosional limit is reached when the cumulative excess work exceeds a given value determined from the time-dependent Hewlett curves. The cumulative excess work is expressed in terms of overflow discharge above a critical discharge that slowly varies in time, similar to a discharge hydrograph. The methodology is easily applied using forecast storm surge hydrographs at specific locations where wave action is minimal. For preliminary planning purposes, when storm surge hydrographs are unavailable, hypothetical equations for the water level and overflow discharge hydrographs are proposed in terms of the values at maximum overflow and the total duration of overflow. An example application is given to illustrate use of the methodology.

  3. Competition among surface roots in a selectively-logged, semi-deciduous forest in southeastern Mexico - effects on seedlings of two species of contrasting shade tolerance

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    Matthew Dickinson; D.F. Wigham

    2013-01-01

    Experimental manipulations of root competition on naturally established seedlings were conducted across canopy openness and soil depth gradients in a selectively-logged, semideciduous forest on limestone-derived soils in southeastern Mexico. We studied the relatively shade intolerant mahogany (Swietenia macrophylla, Meliaceae) and shade tolerant...

  4. Patterns of shading tolerance determined from experimental light reduction studies of seagrasses

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    An extensive review of the experimental literature on seagrass shading evaluated the relationship between experimental light reductions, duration of experiment and seagrass response metrics to determine whether there were consistent statistical patterns. There were highly signif...

  5. Tree cover at fine and coarse spatial grains interacts with shade tolerance to shape plant species distributions across the Alps.

    Science.gov (United States)

    Nieto-Lugilde, Diego; Lenoir, Jonathan; Abdulhak, Sylvain; Aeschimann, David; Dullinger, Stefan; Gégout, Jean-Claude; Guisan, Antoine; Pauli, Harald; Renaud, Julien; Theurillat, Jean-Paul; Thuiller, Wilfried; Van Es, Jérémie; Vittoz, Pascal; Willner, Wolfgang; Wohlgemuth, Thomas; Zimmermann, Niklaus E; Svenning, Jens-Christian

    2015-06-01

    The role of competition for light among plants has long been recognised at local scales, but its importance for plant species distributions at larger spatial scales has generally been ignored. Tree cover modifies the local abiotic conditions below the canopy, notably by reducing light availability, and thus, also the performance of species that are not adapted to low-light conditions. However, this local effect may propagate to coarser spatial grains, by affecting colonisation probabilities and local extinction risks of herbs and shrubs. To assess the effect of tree cover at both the plot- and landscape-grain sizes (approximately 10-m and 1-km), we fit Generalised Linear Models (GLMs) for the plot-level distributions of 960 species of herbs and shrubs using 6,935 vegetation plots across the European Alps. We ran four models with different combinations of variables (climate, soil and tree cover) at both spatial grains for each species. We used partial regressions to evaluate the independent effects of plot- and landscape-grain tree cover on plot-level plant communities. Finally, the effects on species-specific elevational range limits were assessed by simulating a removal experiment comparing the species distributions under high and low tree cover. Accounting for tree cover improved the model performance, with the probability of the presence of shade-tolerant species increasing with increasing tree cover, whereas shade-intolerant species showed the opposite pattern. The tree cover effect occurred consistently at both the plot and landscape spatial grains, albeit most strongly at the former. Importantly, tree cover at the two grain sizes had partially independent effects on plot-level plant communities. With high tree cover, shade-intolerant species exhibited narrower elevational ranges than with low tree cover whereas shade-tolerant species showed wider elevational ranges at both limits. These findings suggest that forecasts of climate-related range shifts for herb

  6. Tree cover at fine and coarse spatial grains interacts with shade tolerance to shape plant species distributions across the Alps

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    Nieto-Lugilde, Diego; Lenoir, Jonathan; Abdulhak, Sylvain; Aeschimann, David; Dullinger, Stefan; Gégout, Jean-Claude; Guisan, Antoine; Pauli, Harald; Renaud, Julien; Theurillat, Jean-Paul; Thuiller, Wilfried; Van Es, Jérémie; Vittoz, Pascal; Willner, Wolfgang; Wohlgemuth, Thomas; Zimmermann, Niklaus E.; Svenning, Jens-Christian

    2015-01-01

    The role of competition for light among plants has long been recognised at local scales, but its importance for plant species distributions at larger spatial scales has generally been ignored. Tree cover modifies the local abiotic conditions below the canopy, notably by reducing light availability, and thus, also the performance of species that are not adapted to low-light conditions. However, this local effect may propagate to coarser spatial grains, by affecting colonisation probabilities and local extinction risks of herbs and shrubs. To assess the effect of tree cover at both the plot- and landscape-grain sizes (approximately 10-m and 1-km), we fit Generalised Linear Models (GLMs) for the plot-level distributions of 960 species of herbs and shrubs using 6,935 vegetation plots across the European Alps. We ran four models with different combinations of variables (climate, soil and tree cover) at both spatial grains for each species. We used partial regressions to evaluate the independent effects of plot- and landscape-grain tree cover on plot-level plant communities. Finally, the effects on species-specific elevational range limits were assessed by simulating a removal experiment comparing the species distributions under high and low tree cover. Accounting for tree cover improved the model performance, with the probability of the presence of shade-tolerant species increasing with increasing tree cover, whereas shade-intolerant species showed the opposite pattern. The tree cover effect occurred consistently at both the plot and landscape spatial grains, albeit most strongly at the former. Importantly, tree cover at the two grain sizes had partially independent effects on plot-level plant communities. With high tree cover, shade-intolerant species exhibited narrower elevational ranges than with low tree cover whereas shade-tolerant species showed wider elevational ranges at both limits. These findings suggest that forecasts of climate-related range shifts for herb

  7. Population structure of Rudgea parquioides (Rubiaceae, a shade-tolerant shrub species, in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Fernanda C.G. Cardoso

    2010-09-01

    Full Text Available The expectations that shade-tolerant forest species show 1 a population structure composed by a high amount of small individuals, and 2 biomass allocation for diameter higher than for height growth, were tested for Rudgea parquioides, a typical shrub in Southern Brazil. We described the size structure (height and stem diameter and allometrical relations of a R. parquioides population by counting and measuring all the individuals in a 725m² area in the municipality of Curitiba (25"25'S; 49"19'W. A total of 916 individuals (12,634 ind.ha-1 were recorded in the area. The firstexpectation was supported, since distribution by height and diameter classes showed a predominance of small individuals (skewness coefficients > 1. On the other hand, the regression between height and stem base diameter showed slope β Foram testadas duas hipóteses relativas a espécies florestaistolerantes à sombra em uma população de Rudgea parquioides, um arbusto característico do sul do Brasil: 1 espécies tolerantes à sombra possuem uma estrutura populacional composta por um grande número de indivíduos pequenos e 2 a alocação de biomassa para o crescimento em diâmetro é maior que para o crescimento em altura. Foram descritas as estruturas de tamanho (altura e diâmetro do tronco e relações alométricas através da contagem e medição de todos os indivíduos de R. parquioides em uma área de 725m² no município de Curitiba (25"25'S; 49"19'W. Um total de 916 indivíduos(12.634 ind.ha-1 foi medido nesta área. A primeira hipótese foi aceita, uma vez que a distribuição em classes de altura e de diâmetro mostrou um predomínio de indivíduos pequenos (coeficiente de assimetria > 1. Por outro lado, a regressão entre altura e diâmetro na base do caule mostrou inclinação β < 1, o que indica que o crescimento em altura é maior que em diâmetro, não suportando a segunda hipótese. Esses resultados mostram que as estratégias de crescimento em esp

  8. Scaling allometric relationships in pure, crowded, even-aged stands: do tree shade-tolerance, repro-ductive mode and wood productivity matter?

    OpenAIRE

    Dan Gafta; Florin Crişan

    2013-01-01

    Tree allometric relationships are likely to be influenced by species tolerance to shade, nutrient availability and plant ontogenetic origin. The aim of this paper was to test to what extent these factors affect the scaling exponents of two allometric relationships in pure, even-aged, canopy-closed forest stands: stem diameter (D) versus stem height (H) and versus stem density (N). Data were collected by tree species (Betula pendula, Fagus sylvatica and Quercus petraea), wood productivity clas...

  9. The effect of bleaching, varying the shade or thickness of composite veneers on final colour: an in vitro study.

    Science.gov (United States)

    Jarad, F D; Griffiths, C E; Jaffri, M; Adeyemi, A A; Youngson, C C

    2008-07-01

    To investigate whether bleaching prior to placement of a composite veneer had an effect on the final shade of the restoration and whether this was affected by the thickness or shade of the veneer. Twenty bovine teeth were collected, sectioned and divided into two groups. One group was the non-bleached control, while the other was the bleached group. A colour reading was recorded using a spectrophotometer. The bleached group then underwent external bleaching with 38% hydrogen peroxide and a colour reading was recorded. Each of these two groups were further sub-divided into four subgroups, on which composite veneers were placed. These subgroups were: 0.5 m thick A1, 1 m thick A1, 0.5 mm thick A4 and 1 mm thick A4 composite veneers. Colour readings were recorded after veneer placement. Statistical significance was assessed using analysis of variance. There was a difference between the colour produced for the same veneer properties, between the bleached and non-bleached groups. For a thin (0.5mm) A4 veneer bleaching produced a statistically significant difference in the amount of colour change (DeltaE) compared to veneering alone. For A1, non-bleached group there is a significant difference in the DeltaE produced by altering the thickness of the veneer. Within the limitations of this study, we can conclude that bleaching prior to placement of a thin A4 dark veneer produces a significant difference in colour change. If no bleaching is performed, altering the thickness of an A1 veneer produces a significant colour difference DeltaE. However, if bleaching is carried out there is no significant difference.

  10. The Effect of Elevated Ozone Concentrations with Varying Shading on Dry Matter Loss in a Winter Wheat-Producing Region in China.

    Science.gov (United States)

    Xu, Jingxin; Zheng, Youfei; He, Yuhong; Wu, Rongjun; Mai, Boru; Kang, Hanqing

    2016-01-01

    Surface-level ozone pollution causes crop production loss by directly reducing healthy green leaf area available for carbon fixation. Ozone and its precursors also affect crop photosynthesis indirectly by decreasing solar irradiance. Pollutants are reported to have become even more severe in Eastern China over the last ten years. In this study, we investigated the effect of a combination of elevated ozone concentrations and reduced solar irradiance on a popular winter wheat Yangmai13 (Triticum aestivum L.) at field and regional levels in China. Winter wheat was grown in artificial shading and open-top-chamber environments. Treatment 1 (T1, i.e., 60% shading with an enhanced ozone of 100±9 ppb), Treatment 2 (T2, i.e., 20% shading with an enhanced ozone of 100±9 ppb), and Control Check Treatment (CK, i.e., no shading with an enhanced ozone of 100±9 ppb), with two plots under each, were established to investigate the response of winter wheat under elevated ozone concentrations and varying solar irradiance. At the field level, linear temporal relationships between dry matter loss and cumulative stomatal ozone uptake were first established through a parameterized stomatal-flux model. At the regional level, ozone concentrations and meteorological variables, including solar irradiance, were simulated using the WRF-CMAQ model (i.e., a meteorology and air quality modeling system). These variables were then used to estimate cumulative stomatal ozone uptake for the four major winter wheat-growing provinces. The regional-level cumulative ozone uptake was then used as the independent variable in field data-based regression models to predict dry matter loss over space and time. Field-level results showed that over 85% (T1: R(2) = 0.85 & T2: R(2) = 0.89) of variation in dry matter loss was explained by cumulative ozone uptake. Dry matter was reduced by 3.8% in T1 and 2.2% in T2 for each mmol O3·m(-2) of cumulative ozone uptake. At the regional level, dry matter loss in winter

  11. The Effect of Elevated Ozone Concentrations with Varying Shading on Dry Matter Loss in a Winter Wheat-Producing Region in China.

    Directory of Open Access Journals (Sweden)

    Jingxin Xu

    Full Text Available Surface-level ozone pollution causes crop production loss by directly reducing healthy green leaf area available for carbon fixation. Ozone and its precursors also affect crop photosynthesis indirectly by decreasing solar irradiance. Pollutants are reported to have become even more severe in Eastern China over the last ten years. In this study, we investigated the effect of a combination of elevated ozone concentrations and reduced solar irradiance on a popular winter wheat Yangmai13 (Triticum aestivum L. at field and regional levels in China. Winter wheat was grown in artificial shading and open-top-chamber environments. Treatment 1 (T1, i.e., 60% shading with an enhanced ozone of 100±9 ppb, Treatment 2 (T2, i.e., 20% shading with an enhanced ozone of 100±9 ppb, and Control Check Treatment (CK, i.e., no shading with an enhanced ozone of 100±9 ppb, with two plots under each, were established to investigate the response of winter wheat under elevated ozone concentrations and varying solar irradiance. At the field level, linear temporal relationships between dry matter loss and cumulative stomatal ozone uptake were first established through a parameterized stomatal-flux model. At the regional level, ozone concentrations and meteorological variables, including solar irradiance, were simulated using the WRF-CMAQ model (i.e., a meteorology and air quality modeling system. These variables were then used to estimate cumulative stomatal ozone uptake for the four major winter wheat-growing provinces. The regional-level cumulative ozone uptake was then used as the independent variable in field data-based regression models to predict dry matter loss over space and time. Field-level results showed that over 85% (T1: R(2 = 0.85 & T2: R(2 = 0.89 of variation in dry matter loss was explained by cumulative ozone uptake. Dry matter was reduced by 3.8% in T1 and 2.2% in T2 for each mmol O3·m(-2 of cumulative ozone uptake. At the regional level, dry matter

  12. Lack of Physiological Depth Patterns in Conspecifics of Endemic Antarctic Brown Algae: A Trade-Off between UV Stress Tolerance and Shade Adaptation?

    Directory of Open Access Journals (Sweden)

    Iván Gómez

    Full Text Available A striking characteristic of endemic Antarctic brown algae is their broad vertical distribution. This feature is largely determined by the shade adaptation in order to cope with the seasonal variation in light availability. However, during spring-summer months, when light penetrates deep in the water column these organisms have to withstand high levels of solar radiation, including UV. In the present study we examine the light use characteristics in parallel to a potential for UV tolerance (measured as content of phenolic compounds, antioxidant activity and maximum quantum yield of fluorescence in conspecific populations of four Antarctic brown algae (Ascoseira mirabilis, Desmarestia menziesii, D. anceps and Himantothallus grandifolius distributed over a depth gradient between 5 and 30 m. The main results indicated that a photosynthetic efficiency was uniform along the depth gradient in all the studied species, and b short-term (6 h exposure to UV radiation revealed a high tolerance measured as chlorophyll fluorescence, phlorotannin content and antioxidant capacity. Multivariate analysis of similarity indicated that light requirements for photosynthesis, soluble phlorotannins and antioxidant capacity are the variables determining the responses along the depth gradient in all the studied species. The suite of physiological responses of algae with a shallower distribution (A. mirabilis and D. menziesii differed from those with deeper vertical range (D. anceps and H. grandifolius. These patterns are consistent with the underwater light penetration that defines two zones: 0-15 m, with influence of UV radiation (1% of UV-B and UV-A at 9 m and 15 m respectively and a zone below 15 m marked by PAR incidence (1% up to 30 m. These results support the prediction that algae show a UV stress tolerance capacity along a broad depth range according to their marked shade adaptation. The high contents of phlorotannins and antioxidant potential appear to be

  13. Seedling root morphology and biomass allocation of 62 tropical tree species in relation to drought- and shade-tolerance

    NARCIS (Netherlands)

    Markesteijn, L.; Poorter, L.

    2009-01-01

    Water availability is the main determinant of species' distribution in lowland tropical forests. Species' occurrence along water availability gradients depends on their ability to tolerate drought. To identify species' traits underlying drought-tolerance we excavated first year seedlings of 62 dry

  14. On the use of adaptive multiresolution method with time-varying tolerance for compressible fluid flows

    Science.gov (United States)

    Soni, V.; Hadjadj, A.; Roussel, O.

    2017-12-01

    In this paper, a fully adaptive multiresolution (MR) finite difference scheme with a time-varying tolerance is developed to study compressible fluid flows containing shock waves in interaction with solid obstacles. To ensure adequate resolution near rigid bodies, the MR algorithm is combined with an immersed boundary method based on a direct-forcing approach in which the solid object is represented by a continuous solid-volume fraction. The resulting algorithm forms an efficient tool capable of solving linear and nonlinear waves on arbitrary geometries. Through a one-dimensional scalar wave equation, the accuracy of the MR computation is, as expected, seen to decrease in time when using a constant MR tolerance considering the accumulation of error. To overcome this problem, a variable tolerance formulation is proposed, which is assessed through a new quality criterion, to ensure a time-convergence solution for a suitable quality resolution. The newly developed algorithm coupled with high-resolution spatial and temporal approximations is successfully applied to shock-bluff body and shock-diffraction problems solving Euler and Navier-Stokes equations. Results show excellent agreement with the available numerical and experimental data, thereby demonstrating the efficiency and the performance of the proposed method.

  15. Best of both worlds: simultaneous high-light and shade-tolerance adaptations within individual leaves of the living stone Lithops aucampiae.

    Directory of Open Access Journals (Sweden)

    Katie J Field

    Full Text Available "Living stones" (Lithops spp. display some of the most extreme morphological and physiological adaptations in the plant kingdom to tolerate the xeric environments in which they grow. The physiological mechanisms that optimise the photosynthetic processes of Lithops spp. while minimising transpirational water loss in both above- and below-ground tissues remain unclear. Our experiments have shown unique simultaneous high-light and shade-tolerant adaptations within individual leaves of Lithops aucampiae. Leaf windows on the upper surfaces of the plant allow sunlight to penetrate to photosynthetic tissues within while sunlight-blocking flavonoid accumulation limits incoming solar radiation and aids screening of harmful UV radiation. Increased concentration of chlorophyll a and greater chlorophyll a:b in above-ground regions of leaves enable maximum photosynthetic use of incoming light, while inverted conical epidermal cells, increased chlorophyll b, and reduced chlorophyll a:b ensure maximum absorption and use of low light levels within the below-ground region of the leaf. High NPQ capacity affords physiological flexibility under variable natural light conditions. Our findings demonstrate unprecedented physiological flexibility in a xerophyte and further our understanding of plant responses and adaptations to extreme environments.

  16. Acclimation of shade-tolerant and light-resistant Tradescantia species to growth light: chlorophyll a fluorescence, electron transport, and xanthophyll content.

    Science.gov (United States)

    Mishanin, Vladimir I; Trubitsin, Boris V; Patsaeva, Svetlana V; Ptushenko, Vasily V; Solovchenko, Alexei E; Tikhonov, Alexander N

    2017-09-01

    In this study, we have compared the photosynthetic characteristics of two contrasting species of Tradescantia plants, T. fluminensis (shade-tolerant species), and T. sillamontana (light-resistant species), grown under the low light (LL, 50-125 µmol photons m(-2) s(-1)) or high light (HL, 875-1000 µmol photons m(-2) s(-1)) conditions during their entire growth period. For monitoring the functional state of photosynthetic apparatus (PSA), we measured chlorophyll (Chl) a emission fluorescence spectra and kinetics of light-induced changes in the heights of fluorescence peaks at 685 and 740 nm (F 685 and F 740). We also compared the light-induced oxidation of P700 and assayed the composition of carotenoids in Tradescantia leaves grown under the LL and HL conditions. The analyses of slow induction of Chl a fluorescence (SIF) uncovered different traits in the LL- and HL-grown plants of ecologically contrasting Tradescantia species, which may have potential ecophysiological significance with respect to their tolerance to HL stress. The fluorometry and EPR studies of induction events in chloroplasts in situ demonstrated that acclimation of both Tradescantia species to HL conditions promoted faster responses of their PSA as compared to LL-grown plants. Acclimation of both species to HL also caused marked changes in the leaf anatomy and carotenoid composition (an increase in Violaxanthin + Antheraxantin + Zeaxanthin and Lutein pools), suggesting enhanced photoprotective capacity of the carotenoids in the plants grown in nature under high irradiance. Collectively, the results of the present work suggest that the mechanisms of long-term PSA photoprotection in Tradescantia are based predominantly on the light-induced remodeling of pigment-protein complexes in chloroplasts.

  17. Zero tolerance enforcement varies with laws and practices among U.S. states

    Science.gov (United States)

    2000-03-11

    All states now have zero tolerance laws prohibiting people younger than 21 from driving with any positive blood alcohol concentration (BAC). Congress made zero tolerance a national standard in 1995, passing a law to withhold highway funds from states...

  18. Scaling allometric relationships in pure, crowded, even-aged stands: do tree shade-tolerance, repro-ductive mode and wood productivity matter?

    Directory of Open Access Journals (Sweden)

    Dan Gafta

    2013-12-01

    Full Text Available Tree allometric relationships are likely to be influenced by species tolerance to shade, nutrient availability and plant ontogenetic origin. The aim of this paper was to test to what extent these factors affect the scaling exponents of two allometric relationships in pure, even-aged, canopy-closed forest stands: stem diameter (D versus stem height (H and versus stem density (N. Data were collected by tree species (Betula pendula, Fagus sylvatica and Quercus petraea, wood productivity class and reproductive mode (seed origin and sprouting stands from published forest yield tables. Reduced major axis analysis was used to estimate the slopes of regression lines in the log-log space of H-D and D-N. The scaling exponent of the H-D relationship was significantly larger in birch than in beech stands (0.897 versus 0.745, and in low productivity, beech stands as compared with their high productivity counterparts (0.876 versus 0.745. However, no significant difference was detected between high stands and coppices of durmast oak. The scaling exponent of the D-N relationship was significantly larger in birch than in beech stands (-0.690 versus -0.558, in low than in high productivity beech stands (-0.694 versus -0.558, and in seed origin than in sprouting stands of durmast oak (-0.609 versus -0.580. We explained these results in terms of plant stem growth strategies and resource availability from a biomechanical perspective. Contrary to certain studies that have reported an invariant scaling relation between stem diameter and density across tree species and communities, but in accordance with other recent studies, we have brought new evidence on species-specific allometric scaling under self-thinning. In addition, we have revealed within-species variance of the scaling exponent of stem diameter-density relationship.

  19. Scaling allometric relationships in pure, crowded, even-aged stands: do tree shade-tolerance, repro-ductive mode and wood productivity matter?

    Directory of Open Access Journals (Sweden)

    Dan Gafta

    2010-09-01

    Full Text Available Tree allometric relationships are likely to be influenced by species tolerance to shade, nutrient availability and plant ontogenetic origin. The aim of this paper was to test to what extent these factors affect the scaling exponents of two allometric relationships in pure, even-aged, canopy-closed forest stands: stem diameter (D versus stem height (H and versus stem density (N. Data were collected by tree species (Betula pendula, Fagus sylvatica and Quercus petraea, wood productivity class and reproductive mode (seed origin and sprouting stands from published forest yield tables. Reduced major axis analysis was used to estimate the slopes of regression lines in the log-log space of H-D and D-N. The scaling exponent of the H-D relationship was significantly larger in birch than in beech stands (0.897 versus 0.745, and in low productivity, beech stands as compared with their high productivity counterparts (0.876 versus 0.745. However, no significant difference was detected between high stands and coppices of durmast oak. The scaling exponent of the D-N relationship was significantly larger in birch than in beech stands (-0.690 versus -0.558, in low than in high productivity beech stands (-0.694 versus -0.558, and in seed origin than in sprouting stands of durmast oak (-0.609 versus -0.580. We explained these results in terms of plant stem growth strategies and resource availability from a biomechanical perspective.Contrary to certain studies that have reported an invariant scaling relation between stem diameter and density across tree species and communities, but in accordance with other recent studies, we have brought new evidence on species-specific allometric scaling under self-thinning. In addition, we have revealed within-species variance of the scaling exponent of stem diameter-density relationship.

  20. Physiological Response to Salinity and Alkalinity of Rice Genotypes of Varying Salt Tolerance Grown in Field Lysimeters

    Directory of Open Access Journals (Sweden)

    Surekha Rao, P.

    2013-02-01

    Full Text Available Soil salinity and alkalinity seriously threaten rice production in south Asia. Improving screening methodologies to identify sources of tolerance for improved breeding for salt tolerant rice is of continuing importance. Rice genotypes of varying salt tolerance, such as tolerant (T, semi-tolerant (ST, and sensitive (S, were grown in field lysimeters in saline soil of ECe 4 and 8 mS cm-1 and alkali soil of pH 9.5 and 9.8 in North India and analyzed for chlorophyll (Chl, sugar, starch and proline in leaves. Chlorophyll a and b decreased due to salinity in all the tolerance groups. However, Chl a was not much affected but chl b increased with alkalinity. Under high stress both at ECe 8 and pH 9.8 Chl a and b were more in tolerant than in sensitive genotypes. The ratio of Chl a/b was similar in T, ST and S genotypes under salinity stress. Sugar accumulation was higher in T compared to S under normal conditions but under salinity or alkalinity stress the differences were not significant. Leaf starch was highest in T, intermediate in ST and lowest in S genotypes in normal as well as under salinity and alkalinity stress. There was decrease in starch with salinity and alkalinity stress only in T group but not in ST and S group. Proline increased significantly in all the tolerance groups even at low salinity of ECe 4 mS cm -1 or pH 9.5. The salt tolerant genotypes of rice maintained higher levels of Chl a and b, starch and proline under high salinity and alkalinity stress and are the robust criteria for tolerating high salinity and alkalinity.

  1. Responses of legumes and grasses to non-, moderate, and dense shade in Missouri, USA. I. Forage yield and its species-level plasticity

    Science.gov (United States)

    Kejia Pang; J.W. Van Sambeek; Nadia E. Navarrete-Tindall; Chung-Ho Lin; Shibu Jose; H. E. Garrett

    2017-01-01

    Annual screenings of forage grasses and legumes for shade tolerance were conducted from 1996 to 2001 in the outdoor Shade Tolerance Screening Laboratory at the Horticulture and Agroforestry Research Center, University of Missouri. Forty-three forages were grown under non-shade (100% of full sunlight), moderate shade (45%), and dense shade (20%) without competition for...

  2. Responses of legumes and grasses to non-, moderate, and dense shade in Missouri, USA. II. Forage quality and its species-level plasticity

    Science.gov (United States)

    Kejia Pang; J.W. Van Sambeek; Nadia E. Navarrete-Tindall; Chung-Ho Lin; Shibu Jose; H. E. Garrett

    2017-01-01

    From a series of shade tolerance screening trials conducted in an outdoor Shade Tolerance Screening Laboratory, 22 forages (16 grasses and 6 legumes) were selected for quality evaluation. The forages were grown under non-shade (100% of full sun, the control), moderate shade (45%), and dense shade (20%) with adequate water and nutrients and free of competition from...

  3. Fault tolerant control for unstable systems: A linear time varying approach

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, Hans Henrik

    2004-01-01

    In (passive) fault tolerant control design, the objective is to find a fixed compensator, which will maintain a suitable performance - or at least stability - in the event that a fault should occur. A major theoretical obstacle to obtain this objective, is that even if the system models correspon...

  4. When growing tall is not an option : contrasting shade avoidance responses in two wild Geranium species

    NARCIS (Netherlands)

    Gommers, C.M.M.|info:eu-repo/dai/nl/37273023X

    2016-01-01

    Plants can deal with shade in different ways. Sun-adapted species express a set of growth traits to reach for light; the so-called shade avoidance syndrome (SAS). However, shade-tolerant species from the forest understory are not able to outgrow surrounding trees and adopt a tolerance strategy

  5. Robust and Fault-Tolerant Linear Parameter-Varying Control of Wind Turbines

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Esbensen, Thomas; Stoustrup, Jakob

    2011-01-01

    a robust controller (RC). This controller is able to take into account model uncertainties in the aerodynamic model. The controllers are based on output feedback and are scheduled on an estimated wind speed to manage the parameter-varying nature of the model. Furthermore, the AFTC relies on information...

  6. Postprandial Reactive Hypoglycaemia: Varying Presentation Patterns on Extended Glucose Tolerance Tests and Possible Therapeutic Approaches

    Directory of Open Access Journals (Sweden)

    Kevin Stuart

    2013-01-01

    Full Text Available Reactive hypoglycemia is a state characterised by sympathetic or neuroglycopenic symptoms associated with hypoglycaemia in the postprandial state resulting in considerable distress to the patient. It is our practice to carry out either extended glucose tolerance tests (eGTTs or mixed meal tests in these patients. We describe two patients who experienced hypoglycaemic symptoms early and late during eGTT. The patient who experienced symptoms early, in contrast to the patient who presented with late symptoms, did not possess any characteristics of the metabolic syndrome. Based on clinical symptoms, glucose, insulin, and free fatty acid (FFA levels, we speculate on possible mechanisms that may have accounted for each of their presentation patterns. We then discuss low glycaemic index diet which will be the mainstay of management.

  7. Effect of intra- and interspecific competition on the performance of native and invasive species of Impatiens under varying levels of shade and moisture.

    Science.gov (United States)

    Skálová, Hana; Jarošík, Vojtěch; Dvořáčková, Śárka; Pyšek, Petr

    2013-01-01

    Many alien plants are thought to be invasive because of unique traits and greater phenotypic plasticity relative to resident species. However, many studies of invasive species are unable to quantify the importance of particular traits and phenotypic plasticity in conferring invasive behavior because traits used in comparative studies are often measured in a single environment and by using plants from a single population. To obtain a deeper insight into the role of environmental factors, local differences and competition in plant invasions, we compared species of Impatiens (Balsaminaceae) of different origin and invasion status that occur in central Europe: native I. noli-tangere and three alien species (highly invasive I. glandulifera, less invasive I. parviflora and potentially invasive I. capensis). In two experiments we harvested late-stage reproductive plants to estimate performance. The first experiment quantified how populations differed in performance under varying light and moisture levels in the absence of competition. The second experiment quantified performance across these environments in the presence of intra- and inter-specific competition. The highly invasive I. glandulifera was the strongest competitor, was the tallest and produced the greatest biomass. Small size and high plasticity were characteristic for I. parviflora. This species appeared to be the second strongest competitor, especially under low soil moisture. The performance of I. capensis was within the range of the other Impatiens species studied, but sometimes limited by alien competitors. Our results suggest that invasion success within the genus Impatiens depends on the ability to grow large under a range of environmental conditions, including competition. The invasive species also exhibited greater phenotypic plasticity across environmental conditions than the native species. Finally, the decreased performance of the native I. noli-tangere in competition with other species studied

  8. Effect of intra- and interspecific competition on the performance of native and invasive species of Impatiens under varying levels of shade and moisture.

    Directory of Open Access Journals (Sweden)

    Hana Skálová

    Full Text Available Many alien plants are thought to be invasive because of unique traits and greater phenotypic plasticity relative to resident species. However, many studies of invasive species are unable to quantify the importance of particular traits and phenotypic plasticity in conferring invasive behavior because traits used in comparative studies are often measured in a single environment and by using plants from a single population. To obtain a deeper insight into the role of environmental factors, local differences and competition in plant invasions, we compared species of Impatiens (Balsaminaceae of different origin and invasion status that occur in central Europe: native I. noli-tangere and three alien species (highly invasive I. glandulifera, less invasive I. parviflora and potentially invasive I. capensis. In two experiments we harvested late-stage reproductive plants to estimate performance. The first experiment quantified how populations differed in performance under varying light and moisture levels in the absence of competition. The second experiment quantified performance across these environments in the presence of intra- and inter-specific competition. The highly invasive I. glandulifera was the strongest competitor, was the tallest and produced the greatest biomass. Small size and high plasticity were characteristic for I. parviflora. This species appeared to be the second strongest competitor, especially under low soil moisture. The performance of I. capensis was within the range of the other Impatiens species studied, but sometimes limited by alien competitors. Our results suggest that invasion success within the genus Impatiens depends on the ability to grow large under a range of environmental conditions, including competition. The invasive species also exhibited greater phenotypic plasticity across environmental conditions than the native species. Finally, the decreased performance of the native I. noli-tangere in competition with other

  9. Drought tolerance of tropical tree species : functional traits, trade-offs and species distribution

    NARCIS (Netherlands)

    Markesteijn, L.

    2010-01-01

    KEY-WORDS: Bolivia, drought tolerance, shade tolerance, functional traits, trade-offs, ecophysiology, species distribution Tropical forests occur under rainfall regimes that vary greatly in the rainfall pattern and frequency and intensity of drought. Consequently water availability is one of the

  10. Mechanisms of drought-induced dissipation of excitation energy in sun- and shade-adapted drought-tolerant mosses studied by fluorescence yield change and global and target analysis of fluorescence decay kinetics.

    Science.gov (United States)

    Yamakawa, Hisanori; van Stokkum, Ivo H M; Heber, Ulrich; Itoh, Shigeru

    2017-11-18

    Some mosses stay green and survive long even under desiccation. Dissipation mechanisms of excess excitation energy were studied in two drought-tolerant moss species adapted to contrasting niches: shade-adapted Rhytidiadelphus squarrosus and sun-adapted Rhytidium rugosum in the same family. (1) Under wet conditions, a light-induced nonphotochemical quenching (NPQ) mechanism decreased the yield of photosystem II (PSII) fluorescence in both species. The NPQ extent saturated at a lower illumination intensity in R. squarrosus, suggesting a larger PSII antenna size. (2) Desiccation reduced the fluorescence intensities giving significantly lower F 0 levels and shortened the overall fluorescence lifetimes in both R. squarrosus and R. rugosum, at room temperature. (3) At 77 K, desiccation strongly reduced the PSII fluorescence intensity. This reduction was smaller in R. squarrosus than in R. rugosum. (4) Global and target analysis indicated two different mechanisms of energy dissipation in PSII under desiccation: the energy dissipation to a desiccation-formed strong fluorescence quencher in the PSII core in sun-adapted R. rugosum (type-A quenching) and (5) the moderate energy dissipation in the light-harvesting complex/PSII in shade-adapted R. squarrosus (type-B quenching). The two mechanisms are consistent with the different ecological niches of the two mosses.

  11. Patterns of inflammatory responses and parasite tolerance vary with malaria transmission intensity.

    Science.gov (United States)

    Ademolue, Temitope W; Aniweh, Yaw; Kusi, Kwadwo A; Awandare, Gordon A

    2017-04-11

    In individuals living in malaria-endemic regions, parasitaemia thresholds for the onset of clinical symptoms vary with transmission intensity. The mechanisms that mediate this relationship are however, unclear. Since inflammatory responses to parasite infection contribute to the clinical manifestation of malaria, this study investigated inflammatory cytokine responses in children with malaria from areas of different transmission intensities (ranging from low to high). Blood samples were obtained from children confirmed with malaria at community hospitals in three areas with differing transmission intensities. Cytokine levels were assessed using the Luminex®-based magnetic bead array system, and levels were compared across sites using appropriate statistical tests. The relative contributions of age, gender, parasitaemia and transmission intensity on cytokine levels were investigated using multivariate regression analysis. Parasite density increased with increasing transmission intensity in children presenting to hospital with symptomatic malaria, indicating that the parasitaemia threshold for clinical malaria increases with increasing transmission intensity. Furthermore, levels of pro-inflammatory cytokines, including tumour necrosis factor alpha (TNF-α), interferon-gamma (IFN-γ), interleukin (IL)-1β, IL-2, IL-6, IL-8, and IL-12, decreased with increasing transmission intensity, and correlated significantly with parasitaemia levels in the low transmission area but not in high transmission areas. Similarly, levels of anti-inflammatory cytokines, including IL-4, IL-7, IL-10 and IL-13, decreased with increasing transmission intensity, with IL-10 showing strong correlation with parasitaemia levels in the low transmission area. Multiple linear regression analyses revealed that transmission intensity was a stronger predictor of cytokine levels than age, gender and parasitaemia. Taken together, the data demonstrate a strong relationship between the prevailing

  12. An audit of shade reproduction of fixed metal ceramic prostheses.

    Science.gov (United States)

    Finch, Karl; Jarad, Fadi D; Adeyemi, Adejumoke Adeola; Al-Shamaa, Sawsan

    2011-09-01

    This investigation aimed to evaluate the colour difference between metal ceramic restorations and their corresponding shades and any reasons for a colour mismatch in the dental laboratory. The colour of 50 consecutive metal ceramic restorations produced in a laboratory was measured using a spectrophotometer and compared to the shade tabs. Colour reproduction was optimal at porcelain thicknesses between 1.4-1.6 mm, varied between technicians within the same laboratory and was better for shades in the 2M group. Most crowns were above the threshold for a clinically acceptable shade match and almost all crowns were lighter than the corresponding shade tab.

  13. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated...... by the desire to experiment and to become otherwise. The objective is to discuss what gets lost, conceptually as well as politically, when we neglect the subsistence of active tolerance within other practices of tolerance, and to develop a theory of active tolerance in which tolerance's mobilizing character...... the current models of restraint and benevolence, other ways of understanding the politics of democratic pluralism might be developed, which will enable us to conceive of tolerance's future in terms different than those currently on offer. Tolerance: A Sensorial Orientation to Politics develops...

  14. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated by the d...... these alternatives by returning to the notion of tolerance as the endurance of pain, linking this notion to exemplars and theories relevant to the politics of multiculturalism, religious freedom, and free speech....

  15. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated by the d...... these alternatives by returning to the notion of tolerance as the endurance of pain, linking this notion to exemplars and theories relevant to the politics of multiculturalism, religious freedom, and free speech.......Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated...... by the desire to experiment and to become otherwise. The objective is to discuss what gets lost, conceptually as well as politically, when we neglect the subsistence of active tolerance within other practices of tolerance, and to develop a theory of active tolerance in which tolerance's mobilizing character...

  16. TNFα dynamics during the oral glucose tolerance test vary according to the level of insulin resistance in pregnant women.

    Science.gov (United States)

    Guillemette, Laetitia; Lacroix, Marilyn; Battista, Marie-Claude; Doyon, Myriam; Moreau, Julie; Ménard, Julie; Ardilouze, Jean-Luc; Perron, Patrice; Hivert, Marie-France

    2014-05-01

    TNFα is suspected to play a role in inflammation and insulin resistance leading to higher risk of metabolic impairment. Controversies exist concerning the role of TNFα in gestational insulin resistance. We investigated the interrelations between TNFα and insulin resistance in a large population-based cohort of pregnant women. Women (n = 756) were followed prospectively at 5-16 weeks and 24-28 weeks of pregnancy. Anthropometric measures and blood samples were collected at both visits. A 75-g oral glucose tolerance test (OGTT) was conducted at the second trimester to assess insulin sensitivity status (homeostasis model of assessment of insulin resistance and Matsuda index). TNFα was measured at the first trimester (nonfasting) and at each time point of the OGTT. Participants were 28.4 ± 4.4 years old and had a mean body mass index of 25.5 ± 5.5 kg/m(2) at first trimester. Median TNFα levels were 1.56 (interquartile range, 1.18-2.06) pg/mL at first trimester and 1.61 (interquartile range, 1.12-2.13) pg/mL at second trimester (1 h after glucose load). At second trimester, higher TNFα levels were associated with higher insulin resistance index levels (r = 0.37 and -0.30 for homeostasis model of assessment of insulin resistance and Matsuda index, respectively; P < .0001), even after adjustment for age, body mass index, triglycerides, and adiponectin. Women with higher insulin resistance showed a continuing decrease in TNFα levels during the OGTT, whereas women who were more insulin sensitive showed an increase in TNFα at hour 1 and a decrease at hour 2 of the test. Higher insulin resistance is associated with higher levels of circulating TNFα at first and second trimesters of pregnancy. TNFα level dynamics during an OGTT at second trimester vary according to insulin-resistance state.

  17. SHADE3 server

    DEFF Research Database (Denmark)

    Madsen, Anders Østergaard; Hoser, Anna Agnieszka

    2014-01-01

    A major update of the SHADE server (http://shade.ki.ku.dk) is presented. In addition to all of the previous options for estimating H-atom anisotropic displacement parameters (ADPs) that were offered by SHADE2, the newest version offers two new methods. The first method combines the original...... translation-libration-screw analysis with input from periodic ab initio calculations. The second method allows the user to input experimental information from spectroscopic measurements or from neutron diffraction experiments on related structures and utilize this information to evaluate ADPs of H atoms...

  18. Lightness, chroma and hue differences on visual shade matching.

    Science.gov (United States)

    Pecho, Oscar E; Pérez, María M; Ghinea, Razvan; Della Bona, Alvaro

    2016-11-01

    To analyze the influence of lightness, chroma and hue differences on visual shade matching performed by dental students. 100 dental students (DS) volunteers with normal vision participated in the study. A spectroradiometer (SP) was used to measure the spectral reflectance of 4 extracted human upper central incisors (UCI 1-4) and shade tabs from Vita Classical (VC) and Vita Toothguide 3D-Master (3D) shade guides. Measurements were performed over a gray background, inside a viewing booth and under D65 illuminant (diffuse/0° geometry). Color parameters (L*, a*, b*, C* and h°) were calculated. DS used VC and 3D to visually select the best shade match for each UCI. CIE metric differences (Δa*,Δb*,ΔL', ΔC' and ΔH') and CIEDE2000(2:1:1) lightness (ΔEL), chroma (ΔEC) and hue (ΔEH) differences were obtained from each UCI and the first three shades selected by DS and the first option using CIELAB, CIEDE2000(1:1:1) and CIEDE2000(2:1:1) color difference metrics. The closest CIELAB color-discrimination ellipsoid (from RIT-DuPont visual color-difference data) to each UCI was selected for the analysis of visual shade matching. DS showed a preference for shades with lower chroma (ΔC' and ΔEC) and/or hue (ΔH' and ΔEH) values instead of shades with lower lightness values (ΔL' and ΔEL). Most best visual matches were near the tolerance ellipsoid centered on tooth shade. This study is an attempt to partially explain the inconsistencies between visual and instrumental shade matching and the limitations of shade guides. Visual shade matching was driven by color differences with lower chroma and hue values. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  19. Shade selection in dentistry

    OpenAIRE

    H. Benaz

    1996-01-01

    Identifying the shades is difficult and needs not only the science but also the art. In order to match and coordinate the shades, distinguishing them is essential. As well as hue, chroma and value, Maverick stains are also considered. Various factors effect color perception such as the difference between the eyes' vision, age, drugs and psychology of the colors. Surface texture is considerably important in adjusting teeth color. Color is the light reflected from teeth struct...

  20. The effect of the interaction between glucose tolerance and breakfasts varying in carbohydrate and fibre on mood and cognition.

    Science.gov (United States)

    Nabb, Samantha L; Benton, David

    2006-01-01

    As a glucose containing drink has been reported to improve memory, and missing breakfast has been reported to adversely influence memory late in the morning, meals designed to differ in their ability to release glucose into the blood stream were contrasted. Using a factorial design, breakfasts containing 15, 30 or 50 g of carbohydrate and 1.5, 6 or 13 g of fibre were compared. The glucose tolerance of participants proved to be an important factor. Those with better tolerance reported better mood. Those eating breakfasts containing greater amounts of carbohydrate reported feeling tired rather than energetic. The amount of carbohydrate did not negatively affect memory in those with better glucose tolerance, however, the consumption of more carbohydrate resulted in more forgetting in those with poorer glucose tolerance. The effect with reactions times differed from memory in that a greater intake of carbohydrate resulted in faster responses later in the morning.

  1. Intrarater repeatability of shade selections with two shade guides.

    Science.gov (United States)

    Hammad, Ihab A

    2003-01-01

    Color research has shown that shade guides do not always represent the color of natural teeth. Moreover, visual evaluation has been found to be unreliable and inconsistent. This investigation evaluated the effects of 2 shade guides on the intrarater repeatability (reliability) of prosthodontists and general practitioners with regard to shade selection. Ten prosthodontists and ten general practitioners (all men, 35-45 years old) with an average practice experience of 14 years participated in this study. Examiners were tested to eliminate color blindness. Each clinician used Vita Lumin Vacuum and Vitapan 3D-Master shade guides to determine the shades of the maxillary right canines of 20 patients following a standard protocol. The identification codes of the shade tabs were masked to prevent shade memory. All teeth were polished before each shade selection, and the selection process was standardized for controlled lighting and procedures. Shade selections were randomly repeated 1 month later by the same practitioners on the same group of patients in accordance with the same shade-selection protocol. Analysis of variance and t tests for individual comparisons among means were performed (P3D-Master shade guide significantly improved the intrarater repeatability of general practitioners compared with the Vita Lumin Vacuum shade guide (P3D-Master shade guide notably improved intrarater repeatability among the general practitioners.

  2. Shading of ceramic crowns using digital tooth shade matching devices.

    Science.gov (United States)

    Baltzer, A; Kaufmann-Jinoian, V

    2005-04-01

    In the 1990s, there was great optimism due to the development of devices for measuring tooth shade. The frequently not so simple, visual determination of the shade of a tooth was to be done with the aid of a device which recognizes the shade and describes it accurately by reference to a color chart. However, the skepticism towards such devices was also great. It is known that the color effect frequently differs strongly when comparing a tooth from the shade guide with a metal ceramic crown, despite identical shade designation. Anyone who considers visual shade determination to be inadequate and places his hopes in digital shade matching devices will be disappointed. It is the shade-generating structures of the metal ceramic and frequently of the veneer layers that turn out to be too thin which, despite correct shade selection, cause a different color perception. Such problems have been reduced decisively with the development of fracture-proof hard porcelain caps (Vita In-Ceram) with optical characteristics similar to teeth. In addition, the Vita System 3D-Master tooth shade system developed in 1998 by Vita in cooperation with Dr. Hall from Australia, leads the practitioner to a better understanding of the primary tooth shade characteristics of "brightness (value)", "color intensity (chroma)" and "color (wave length of the visible light, hue)". These two innovations allow a more accurate estimate of the basic shade of a natural tooth (reference tooth) and the imitation in the laboratory of its natural, shade-generating structures. If digital shade measurement supplements the visual shade estimate, then a further improvement can be expected--especially in the recognition of the basic shade. Qualitative descriptions of subjective shade measurement of a natural tooth and of its imitation in the dental laboratory by ceramics can be found frequently in professional journals and publications. With digital tooth shade matching devices, which apart from the color code of

  3. Distributed fault-tolerant time-varying formation control for high-order linear multi-agent systems with actuator failures.

    Science.gov (United States)

    Hua, Yongzhao; Dong, Xiwang; Li, Qingdong; Ren, Zhang

    2017-11-01

    This paper investigates the fault-tolerant time-varying formation control problems for high-order linear multi-agent systems in the presence of actuator failures. Firstly, a fully distributed formation control protocol is presented to compensate for the influences of both bias fault and loss of effectiveness fault. Using the adaptive online updating strategies, no global knowledge about the communication topology is required and the bounds of actuator failures can be unknown. Then an algorithm is proposed to determine the control parameters of the fault-tolerant formation protocol, where the time-varying formation feasible conditions and an approach to expand the feasible formation set are given. Furthermore, the stability of the proposed algorithm is proven based on the Lyapunov-like theory. Finally, two simulation examples are given to demonstrate the effectiveness of the theoretical results. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Solar shading how to integrate solar shading in sustainable buildings

    CERN Document Server

    Dolmans, Dick; Dutoo, Gonzague; Hall, Anders; Seppänen, Olli

    2010-01-01

    Solar Shading Guidebook gives a solid background on the physics of solar radiation and its behaviour in window with solar shading systems. Major focus of the Guidebook is on the effect of solar shading in the use of energy for cooling, heating and lighting. The book gives also practical guidance for selection, installation and operation of solar shading as well as future trends in integration of HVAC-systems with solar control.

  5. Heat stress in cows at pasture and benefit of shade in a temperate climate region

    Science.gov (United States)

    Veissier, Isabelle; Van laer, Eva; Palme, Rupert; Moons, Christel P. H.; Ampe, Bart; Sonck, Bart; Andanson, Stéphane; Tuyttens, Frank A. M.

    2017-11-01

    Under temperate climates, cattle are often at pasture in summer and are not necessarily provided with shade. We aimed at evaluating in a temperate region (Belgium) to what extent cattle may suffer from heat stress (measured through body temperature, respiration rate and panting score, cortisol or its metabolites in milk, and feces on hot days) and at assessing the potential benefits of shade. During the summer of 2012, 20 cows were kept on pasture without access to shade. During the summer of 2011, ten cows had access to shade (young trees with shade cloth hung between them), whereas ten cows had no access. Climatic conditions were quantified by the Heat Load Index (HLI). In animals without access to shade respiration rates, panting scores, rectal temperatures, and milk cortisol concentrations increased as HLI increased in both 2011 and 2012. Fecal cortisol metabolites varied with HLI in 2011 only. When cattle had access to shade, their use of shade increased as the HLI increased. This effect was more pronounced during the last part of the summer, possibly due to better acquaintance with the shade construction. In this case, shade use increased to 65% at the highest HLI (79). Shade tempered the effects on respiration, rectal temperature, and fecal cortisol metabolites. Milk cortisol was not influenced by HLI for cows using shade for > 10% of the day. Therefore, even in temperate areas, cattle may suffer from heat when they are at pasture in summer and providing shade can reduce such stress.

  6. In vitro model to evaluate reliability and accuracy of a dental shade-matching instrument.

    Science.gov (United States)

    Kim-Pusateri, Seungyee; Brewer, Jane D; Dunford, Robert G; Wee, Alvin G

    2007-11-01

    There are several electronic shade-matching instruments available for clinical use; unfortunately, there are limited acceptable in vitro models to evaluate their reliability and accuracy. The purpose of this in vitro study was to evaluate the reliability and accuracy of a dental clinical shade-matching instrument. Using the shade-matching instrument (ShadeScan), color measurements were made of 3 commercial shade guides (VITA Classical, VITA 3D-Master, and Chromascop). Shade tabs were selected and placed in the middle of a gingival matrix (Shofu Gummy), with tabs of the same nominal shade from additional shade guides placed on both sides. Measurements were made of the central region of the shade tab inside a black box. For the reliability assessment, each shade tab from each of the 3 shade guide types was measured 10 times. For the accuracy assessment, each shade tab from 10 guides of each of the 3 types evaluated was measured once. Reliability, accuracy, and 95% confidence intervals were calculated for each shade tab. Differences were determined by 1-way ANOVA followed by the Bonferroni multiple comparison procedure. Reliability of ShadeScan was as follows: VITA Classical = 95.0%, VITA 3D-Master = 91.2%, and Chromascop = 76.5%. Accuracy of ShadeScan was as follows: VITA Classical = 65.0%, VITA 3D-Master = 54.2%, Chromascop = 84.5%. This in vitro study showed a varying degree of reliability and accuracy for ShadeScan, depending on the type of shade guide system used.

  7. Growth and morphogenesis of sun and shade plants I. The influence of light intensity

    NARCIS (Netherlands)

    Corre, W.J.

    1983-01-01

    A number of herbacious sun and shade plants were grown at different light levels to investigate their adaptations in morphology and growth to light intensity. All species examined respond to low light intensity strongly, but very much the same. It is concluded that shade tolerance is not based on

  8. Light-related variation in sapling architecture of three shade-tolerant tree species of the Mexican rain forest Variación arquitectural de árboles juveniles en relación con la luz en tres especies tolerantes a la sombra en una selva húmeda mexicana

    Directory of Open Access Journals (Sweden)

    JOSÉ LUIS MARTÍNEZ-SÁNCHEZ

    2008-09-01

    Full Text Available The crown architecture of three shade-tolerant tree species (two subcanopy and one mid-canopy was analyzed in relation to the light regime of the forest understorey. The aim was to examine to which extent shade-tolerant species variate in their crown architecture. Tree saplings (265 between 50 and 300 cm height, and distributed from understorey to variously-sized canopy gaps, were measured for 13 architectural traits in the lowland rain forest of Los Tuxtlas, México. The analysis showed that the three species changed their architecture as light increased but in a different way. No species conformed to the typical wide-crown type expected for shade-tolerant species, and in contrast they presented some traits of light demanding species. The two sub-canopy species tended to adopt a crown form between a narrow- and wide-crown type, and the mid-canopy species showed more traits of a narrow-crown type. The horizontal crown area appeared as the more related trait to the light and sapling height. It is concluded that despite being shade-tolerant, the studied species make use of better-lit environments in the forest understorey. The crown architecture of shade-tolerant species is not as rigid as originally conceived.Se analizó la arquitectura de la copa de tres especies tolerantes a la sombra (dos del sotobosque y una del dosel medio en relación con el ambiente lumínico del sotobosque de la selva. El objetivo fue examinar el grado de variación que presenta la arquitectura de la copa de especies tolerantes a la sombra. Para esto, se midieron 13 variables arquitecturales en 265 árboles juveniles (50-300 cm de altura distribuidos desde sitios de selva madura hasta claros de diversos tamaños, en la selva húmeda tropical de Los Tuxtlas, México. El análisis mostró que las tres especies cambian la arquitectura de su copa a medida que aumenta la disponibilidad de luz, pero de diferente forma. Ninguna especie presentó el típico modelo de copa plana

  9. Shades of green

    DEFF Research Database (Denmark)

    Kleinschmit, Daniela; Lindstad, Berit Hauger; Thorsen, Bo Jellesmark

    2014-01-01

    Politics increasingly introduces initiatives supporting a shift toward a bioeconomy aiming at a society relying strongly on renewable biological sources while achieving economic growth efficiently and sustainably. However, the agenda of bioeconomy comprises different “shades of green,” in the sense......, and identify a core set of potential contributions from social sciences for enhancing the bioeconomy in the forest sector. The paper focuses on studies within policy analysis, economics, and business administration disciplines. Thus it presents diverse disciplinary perspectives on the forest sector...

  10. PowerShades. Transparent photovoltaics and solar shading. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bezzel, E. (PhotoSolar ApS, Taastrup (Denmark)); Univ. of Neuchatel, Institute of Microtechnology, Neuchatel (CH)); Savcor Denmark A/S, Ballerup (Denmark)); Chem-Tec Plating A/S, Uldum (Denmark)); Danish Technological Institute (DTI), Taastrup (Denmark))

    2008-06-15

    This report marks the end of the PSO funded R and D project PowerShades. The objective of the project has been to establish knowledge about the manufacturing of PowerShade transparent photovoltaics and to demonstrate the viability of PowerShade, both as a product and when considered a building element. It has not been the objective to demonstrate a full-scale manufacturing of PowerShade, but to establish the knowledge that enables industrial manufacturing. The overall objective of the project has been achieved, and the large majority of the milestones defined have been met to full extent. It has been shown that PowerShade photovoltaic cells with an electrical efficiency of 5% can be reached, and it is expected that future work will lead to even better efficiency. Also, it has been demonstrated by full size side by side comparison that PowerShade transparent photovoltaics may replace exterior solar shading devices without compromise to the thermal properties of the building. The project has identified a number of work areas that must be addressed before an industrial manufacturing can be established. The efficiency of the photovoltaic generator must be increased and the stability of the entire product documented. Also, some of the identified processing steps must be scaled in capacity before manufacturing can be considered. (author)

  11. Photosynthetic responses to understory shade and elevated carbon dioxide concentration in four northern hardwood tree species.

    Science.gov (United States)

    Sefcik, Lesley T; Zak, Donald R; Ellsworth, David S

    2006-12-01

    Seedling responses to elevated atmospheric CO(2) concentration ([CO(2)]) and solar irradiance were measured over two growing seasons in shade-tolerant Acer saccharum Marsh. and Fagus grandifolia J.F. Ehrh. and shade-intolerant Prunus serotina, a J.F. Ehrh. and Betula papyrifera Marsh. Seedlings were exposed to a factorial combination of [CO2] (ambient and elevated (658 micromol mol-1)) and understory shade (deep and moderate) in open-top chambers placed in a forest understory. The elevated [CO(2)] treatment increased mean light-saturated net photosynthetic rate by 63% in the shade-tolerant species and 67% in the shade-intolerant species. However, when measured at the elevated [CO(2)], long-term enhancement of photosynthesis was 10% lower than the instantaneous enhancement seen in ambient-[CO(2)]-grown plants (P < 0.021). Overall, growth light environment affected long-term photosynthetic enhancement by elevated [CO(2)]: as the growth irradiance increased, proportional enhancement due to elevated [CO(2)] decreased from 97% for plants grown in deep shade to 47% for plants grown in moderate shade. Results suggest that in N-limited northern temperate forests, trees grown in deep shade may display greater photosynthetic gains from a CO(2)-enriched atmosphere than trees growing in more moderate shade, because of greater downregulation in the latter environment. If photosynthetic gains by deep-shade-grown plants in response to elevated [CO(2)] translate into improved growth and survival of shade-intolerant species, it could alter the future composition and dynamics of successional forest communities.

  12. Effect of shade on various parameters of Friesian cows in a ...

    African Journals Online (AJOL)

    Lactating cows are particularly sensitive to thermal stress owing to their specialized productive function and to their ... The comfort range for dairy cows varies between -5 and 2I'C. If an animal is subjected ..... Building a shade structure involves a capital investment. During l9M the material cost of the shade structures in the.

  13. Technology reviews: Shading systems

    Energy Technology Data Exchange (ETDEWEB)

    Schuman, J.; Rubinstein, F.; Papamichael, K.; Beltran, L.; Lee, E.S.; Selkowitz, S.

    1992-09-01

    We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice for energy efficiency, ranging from individual components to more complex systems to general design strategies. The purpose of this task is to characterize the state of the art in envelope and lighting technologies in order to identify those with promise for advanced integrated systems, with an emphasis on California commercial buildings. For each technology category, the following activities have been attempted to the extent possible: Identify key performance characteristics and criteria for each technology. Determine the performance range of available technologies. Identify the most promising technologies and promising trends in technology advances. Examine market forces and market trends. Develop a continuously growing in-house database to be used throughout the project. A variety of information sources have been used in these technology characterizations, including miscellaneous periodicals, manufacturer catalogs and cut sheets, other research documents, and data from previous computer simulations. We include these different sources in order to best show the type and variety of data available, however publication here does not imply our guarantee of these data. Within each category, several broad classes are identified, and within each class we examine the generic individual technologies that fall into that class.

  14. Shading, a view from inside

    OpenAIRE

    Koenderink, J.J.; Van Doorn, A.J.; Pont, S.C.

    2012-01-01

    Shape from shading arose from artistic practice, and later experimental psychology, but its formal structure has only been established recently by computer vision. Some of its algorithms have led to useful applications. Psychology has reversely borrowed these formalisms in attempts to come to grips with shading as a depth cue. Results have been less than spectacular. The reason might well be that these formalisms are all based on Euclidean geometry and physics (radiometry), which, are the rig...

  15. Influence of soil pathogens on early regeneration success of tropical trees varies between forest edge and interior.

    Science.gov (United States)

    Krishnadas, Meghna; Comita, Liza S

    2017-11-13

    Soil fungi are key mediators of negative density-dependent mortality in seeds and seedlings, and the ability to withstand pathogens in the shaded understory of closed-canopy forests could reinforce light gradient partitioning by tree species. For four species of tropical rainforest trees-two shade-tolerant and two shade-intolerant-we conducted a field experiment to examine the interactive effects of fungal pathogens, light, and seed density on germination and early seedling establishment. In a fully factorial design, seeds were sown into 1 m2 plots containing soil collected from underneath conspecific adult trees, with plots assigned to forest edge (high light) or shaded understory, high or low density, and fungicide or no fungicide application. We monitored total seed germination and final seedling survival over 15 weeks. Shade-intolerant species were strongly constrained by light; their seedlings survived only at the edge. Fungicide application significantly improved seedling emergence and/or survival for three of the four focal species. There were no significant interactions between fungicide and seed density, suggesting that pathogen spread with increased aggregation of seeds and seedlings did not contribute to pathogen-mediated mortality. Two species experienced significant edge-fungicide interactions, but fungicide effects in edge vs. interior forest varied with species and recruitment stage. Our results suggest that changes to plant-pathogen interactions could affect plant recruitment in human-impacted forests subject to fragmentation and edge-effects.

  16. Heterotrophic respiration in drained tropical peat temperatures influenced by shading gradient

    Science.gov (United States)

    Jauhiainen, Jyrki; Kerojoki, Otto; Silvennoinen, Hanna; Limin, Suwido; Vasander, Harri

    2015-04-01

    Lowland peatlands in Southeast Asia constitute a highly concentrated carbon (C) pool of global significance. These peatlands have formed over periods of several millennia by forest vegetation tolerant to flooding and poor substrates. Uncontrollable drainage and reoccurring wild fires in lack of management after removal of forest cover has impaired the C-storing functions in large reclaimed areas. Intergovernmental Panel on Climate Change (IPCC) reporting sees drained tropical organic soils as one of the largest greenhouse gas emissions releasing terrestrial systems. Vast areas of deforested tropical peatlands do not receive noteworthy shading by vegetation, which increases the amount of solar radiation reaching the peat surface. We studied heterotrophic carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) fluxes in tropical peat in conditions, where; (i) peat temperatures were modified by artificial shading (no shade, 28%, 51% and 90% from the full sun exposure), (ii) root respiration was minimized, (iii) nutrient availability for peat decomposer community was changed (NPK fertilization of 0 and 313 kg ha-1). The experiment was repeated at two over 20 years ago drained fallow agricultural- and degraded sites in Central Kalimantan, Indonesia. Enhanced shading created a lasting decrease in peat temperatures, and decreased diurnal temperature fluctuations, in comparison to less shaded plots. The largest peat temperature difference was between the unshaded and 90% shaded peat surface, where the average temperatures within the topmost 50-cm peat profile differed 3 °C, and diurnal temperatures at 5 cm depth varied up to 4.2 °C in the unshaded and 0.4 °C in the 90% shaded conditions. Highest impacts on the heterotrophic CO2 fluxes caused by the treatments were on agricultural land, where 90% shading from the full exposure resulted in a 33% lower CO2 emission average on the unfertilised plots and a 66% lower emission average on the fertilised plots. Correlation

  17. Performance Improvement of Partially Shaded Photovoltaic Arrays under Moving Shadow Conditions through Shade Dispersion

    Science.gov (United States)

    Vijayalekshmy, S.; Bindu, G. R.; Rama Iyer, S.

    2016-12-01

    Photovoltaic arrays, which are prone to partial shading (PS) reduce the output power than the real power rating of the array. This paper presents the comparative analyses on the electrical characteristics and power losses of a conventional totally cross tied (TCT) configuration, and rearranged TCT (RTCT) in which the modules are physically rearranged in such a way that there is an improvement of power output of array under moving illumination condition (moving cloud). In RTCT, the physical position of the modules is organized based on the Sudoku puzzle pattern so as to scatter the shading effect over the entire array. The rearrangement of modules is performed without varying the electrical connection of the modules in the array. It is validated that the power generation of array under amoving shadow condition is enhanced and the various PS losses are reduced in rearranged configuration.

  18. Branched Chain Amino Acids Are Associated with Insulin Resistance Independent of Leptin and Adiponectin in Subjects with Varying Degrees of Glucose Tolerance.

    Science.gov (United States)

    Connelly, Margery A; Wolak-Dinsmore, Justyna; Dullaart, Robin P F

    2017-05-01

    Branched chain amino acids (BCAA) may be involved in the pathogenesis of insulin resistance and are associated with type 2 diabetes mellitus (T2DM) development. Adipokines such as leptin and adiponectin influence insulin resistance and reflect adipocyte dysfunction. We examined the extent to which the association of BCAA with insulin resistance is attributable to altered leptin and adiponectin levels in individuals with varying degrees of glucose tolerance. BCAA were measured by nuclear magnetic resonance, whereas leptin and adiponectin were measured by immunoassay, in subjects with normal fasting glucose (n = 30), impaired fasting glucose (n = 25), and T2DM (n = 15). Insulin resistance was estimated by homeostasis model assessment (HOMAir). BCAA were higher in men than in women (P BCAA were correlated with HOMAir (r = 0.46; P  0.05). Multivariable linear regression analysis, adjusting for age, sex, T2DM, and body mass index (BMI), demonstrated that BCAA were positively associated with HOMAir (β = 0.242, P = 0.023). When BCAA, leptin, and adiponectin were included together, the positive relationship of HOMAir with BCAA (β = 0.275, P = 0.012) remained significant. Insulin resistance was associated with BCAA. This association remained after adjusting for age, sex, T2DM, BMI, as well as leptin and adiponectin. It is unlikely that the relationship of insulin resistance with BCAA is to a major extent attributable to effects of leptin and adiponectin.

  19. Effects of shading on relative competitive advantage of three species of Sphagnum

    Directory of Open Access Journals (Sweden)

    J.Z. Ma

    2015-06-01

    Full Text Available (1 Sphagnum is an important genus of bryophytes holding 10–15 % of the terrestrial carbon stock. With climate change a drier surface may increase the abundance of vascular plants on peatlands, so shading of Sphagnum may increase. Here we describe growth cabinet experiments to reveal the effects of shading on interactions among mixtures of three species: S. capillifolium, S. palustre (hummock species, and S. fallax (a hollow species. We measured the six traits: growth in length, growth as increase in dry mass, side-shoot production, nitrogen and carbon proportion of the capitulum dry mass, and C:N ratio in the capitulum. (2 Shading had no effect on biomass production or side-shoot production but increased height increment in all three species. It also increased the C and N proportions of total dry mass but decreased C:N ratio in the capitula. (3 Neighbours of a different species reduced biomass and side-shoot production in the two hummock species but had no effect on the hollow species. (4 All three species showed interaction between shading and neighbour in two or more plant traits. S. fallax showed competitive advantage over S. palustre in no-shading treatments and over S. capillifolium in moderate shading treatments. In addition, under deep shading, S. fallax showed a competitive advantage over both hummock species. A clear competitive hierarchy S. fallax>S. capillifolium>S. palustre emerged which was consistent with the hierarchy of side-shoot production. (5 The results suggest that all the species appear to tolerate deep shade (for a few months at least. In a shaded environment, especially under deeply shaded conditions, S. fallax retains its dominance in hollow habitats (if water availability is guaranteed by virtue of its advantage in side-shoot production. (6 If shading increases then the abundance of different Sphagnum species is likely to change.

  20. Assessing the accuracy of computer color matching with a new dental porcelain shade system.

    Science.gov (United States)

    Wang, Jian; Lin, Jin; Gil, Mindy; Seliger, Alison; Da Silva, John D; Ishikawa-Nagai, Shigemi

    2014-03-01

    In a previous study, a novel computer color matching system for dental ceramic restoration was developed, and 21 new shades were established. Theoretically, a natural tooth color can be accurately reproduced by combining 2 or 3 ceramic mixtures from the database of 21 new shades. The purpose of this study was to test the use of these shades in conjunction with the computer color matching system to determine their ability to accurately reproduce the body color of 29 shade tabs from a shade guide (VITAPAN 3D-Master). Disks of 21 reference shades were prepared with porcelain (Cerabien CZR) and polished to 1.0 mm thickness. A spectrophotometer was used to measure the reflectance values from 380 to 780 nm for each disk; the scattering coefficient and absorption coefficient were determined. By using the reflectance values and the scattering and absorption coefficients, the computer color matching program generated porcelain prescriptions incorporating proportions from the 21 reference shades to reproduce the shade tabs. Disks were fabricated from the prescriptions, polished to 1.0 mm thickness, then placed over a zirconia core plate and measured with the spectrophotometer. The color differences (ΔE*) between the shade tabs and the corresponding ceramic disks were calculated. Statistical analysis was performed with the 1-sample t test. The ΔE* values between computer color matching specimens and the target shade tabs varied from 0.5 to 1.9, with an average ΔE* of 1.3, which was significantly less than the clinically detectable ΔE* threshold of 1.6 (P<.001). The computer color matching system with the established 21 new shades is accurate and effective for reproducing tooth shades. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  1. Variations of L*a*b* values among Vitapan Classical Shade Guides.

    Science.gov (United States)

    King, Kenneth A; deRijk, Waldemar G

    2007-01-01

    To measure the variations in L*a*b* values of a group of 25 guides and to assess whether shade guides are indeed interchangeable. The L*a*b* values of individual shade tabs were measured with a LabScan(tm) XE scanning spectrocolorimeter (SSC) with a special attachment for reproducibly positioning shade tabs. Each shade guide (Vitapan Classical, Vident) contained 16 shade tabs. Absolute calibration of the SSC was performed with color tiles traceable to NIST. One shade guide was used to determine the reproducibility of the experimental method by measuring and then removing each shade tab of the standard 10 times. This assessed the variations in observed values induced by the measurement method and the geometry of the specimens. The entire sample consisted of 25 shade guides. The tabs of each of the 25 shade guides were read five times in the SSC, without moving the specimen. Measurements and calculations of E, L*, a*, and b* were performed using Universal Software V4.10 (Hunter Associates Laboratory). The mean, standard deviation, and range were determined of the E, L*, a*, and b* values for each one of the 16 shades in the shade guides. Differences in color are expressed as DeltaE in color science. The standard deviation of E (E(sd)) and the range of E (E(r)) for each of the shades were used as a DeltaE value to assess color differences. For the reproducibility measurements, the shades had values for E(r) varying from 0.08 to 0.69, and E(sd) between 0.02 and 0.22. This established the detection limit for our method for each of the shades. For the group of 25 shade guides, E(r) varied from 0.75 to 3.05, and E(sd) from 0.22 to 0.54. The difference in value of E(r) obtained from the reproducibility test and the E(r) of the group of 25 guides is significant at p < 0.05. The same was found for E(sd). The largest reproducible E(r) observed was 3.05 for shade C1. The differences observed between shade guides are larger than the variations induced by the experimental method

  2. Digital shaded-relief map of Venezuela

    Science.gov (United States)

    Garrity, Christopher P.; Hackley, Paul C.; Urbani, Franco

    2004-01-01

    The Digital Shaded-Relief Map of Venezuela is a composite of more than 20 tiles of 90 meter (3 arc second) pixel resolution elevation data, captured during the Shuttle Radar Topography Mission (SRTM) in February 2000. The SRTM, a joint project between the National Geospatial-Intelligence Agency (NGA) and the National Aeronautics and Space Administration (NASA), provides the most accurate and comprehensive international digital elevation dataset ever assembled. The 10-day flight mission aboard the U.S. Space Shuttle Endeavour obtained elevation data for about 80% of the world's landmass at 3-5 meter pixel resolution through the use of synthetic aperture radar (SAR) technology. SAR is desirable because it acquires data along continuous swaths, maintaining data consistency across large areas, independent of cloud cover. Swaths were captured at an altitude of 230 km, and are approximately 225 km wide with varying lengths. Rendering of the shaded-relief image required editing of the raw elevation data to remove numerous holes and anomalously high and low values inherent in the dataset. Customized ArcInfo Arc Macro Language (AML) scripts were written to interpolate areas of null values and generalize irregular elevation spikes and wells. Coastlines and major water bodies used as a clipping mask were extracted from 1:500,000-scale geologic maps of Venezuela (Bellizzia and others, 1976). The shaded-relief image was rendered with an illumination azimuth of 315? and an altitude of 65?. A vertical exaggeration of 2X was applied to the image to enhance land-surface features. Image post-processing techniques were accomplished using conventional desktop imaging software.

  3. Shading, a view from inside

    NARCIS (Netherlands)

    Koenderink, J.J.; Van Doorn, A.J.; Pont, S.C.

    2012-01-01

    Shape from shading arose from artistic practice, and later experimental psychology, but its formal structure has only been established recently by computer vision. Some of its algorithms have led to useful applications. Psychology has reversely borrowed these formalisms in attempts to come to grips

  4. A Comprehensive Review and Analysis of Solar Photovoltaic Array Configurations under Partial Shaded Conditions

    Directory of Open Access Journals (Sweden)

    R. Ramaprabha

    2012-01-01

    Full Text Available The aim of this paper is to investigate the effects of partial shading on energy output of different Solar Photovoltaic Array (SPVA configurations and to mitigate the losses faced in Solar Photovoltaic (SPV systems by incorporating bypass diodes. Owing to the practical difficulty of conducting experiments on varied array sizes, a generalized MATLAB M-code has been developed for any required array size, configuration, shading patterns, and number of bypass diodes. The proposed model which also includes the insolation-dependent shunt resistance can provide sufficient degree of precision without increasing the computational effort. All the configurations have been analyzed and comparative study is made for different random shading patterns to determine the configuration less susceptible to power losses under partial shading. Inferences have been drawn by testing several shading scenarios.

  5. Clinical effect of different shade guide systems on the tooth shades of ceramic-veneered restorations.

    Science.gov (United States)

    Hassel, Alexander J; Koke, Ulrich; Schmitter, Marc; Beck, Joachim; Rammelsberg, Peter

    2005-01-01

    The objective of this study was to investigate whether a systematically arranged shade guide system (Vita 3D-Master) allows clinicians to achieve a better shade match of a restoration, as compared to a conventional shade guide with a design based on empirical values (Vita Classical). Fifty-nine restorations in 42 patients being treated by student clinicians were assessed. Using 1 of the 2 shade systems assigned randomly, each student independently determined the tooth shade. With the aid of a visual rating scale, the accuracy of the shade match of the finished restoration was assessed. All restorations whose shades had been determined with the 3D-Master could be placed without any further shade corrections. In contrast, almost 17% of restorations determined with the conventional system required subsequent shade modifications. The match of the shades selected with the 3D-Master was judged significantly better by the clinicians. Within the limitations of the study, clinicians with less clinical experience who use a system that guides them through the shade-taking procedure in a relatively systematic manner will be more successful in selecting the correct tooth shade and in avoiding shade corrections. Clinical assessment of the restoration shades showed significant differences between the shade guide with a systematic design and that based on empirical values.

  6. Selecting VITA classical shades with the VITA 3D-master shade guide.

    Science.gov (United States)

    Zenthöfer, Andreas; Wiesberg, Stefan; Hildenbrandt, Achim; Reinelt, Gerhard; Rammelsberg, Peter; Hassel, Alexander J

    2014-01-01

    Although the VITA 3D-Master (3D) shade guide offers improved shade-matching performance, many dental materials are only available in VITA Classical (VC) shades. This study aimed to clarify whether it is possible to convert 3D shades determined by observers into VC shades (indirect method) without adding a clinically significant error in comparison with direct shade determination using the VC shade guide. Forty ceramic specimens were fabricated. L*a*b* values were recorded using a spectroradiometer. Sixty participants (35 dentists, 15 technicians, and 10 students) were recruited and asked to determine the shades of specimens using the VC and 3D shade guides under standardized conditions. Conversion tables were constructed by allocating the closest VC shade tab to every matched 3D shade and by use of an optimization algorithm (indirect methods). Differences between ΔE values for VC matches and for the indirect methods were evaluated using t tests. A mean ΔE (SD) of 4.34 (2.00) for VC and 4.22 (2.21) for 3D was observed (P = .040). Compared with direct shade matching using VC, the indirect method with the optimized tables resulted in a mean ΔE of 4.32 (1.96), which was not significantly different (P = .586). Within the limitations of this study, the conversion tables were suitable for the determination of tooth color using the 3D shade guide followed by conversion into VC shades without adding a clinically significant error.

  7. Shade determination using camouflaged visual shade guides and an electronic spectrophotometer.

    Science.gov (United States)

    Kvalheim, S F; Øilo, M

    2014-03-01

    The aim of the present study was to compare a camouflaged visual shade guide to a spectrophotometer designed for restorative dentistry. Two operators performed analyses of 66 subjects. One central upper incisor was measured four times by each operator; twice with a camouflaged visual shade guide and twice with a spectrophotometer Both methods had acceptable repeatability rates, but the electronic shade determination showed higher repeatability. In general, the electronically determined shades were darker than the visually determined shades. The use of a camouflaged visual shade guide seems to be an adequate method to reduce operator bias.

  8. Color Parameters of the Chromascop Shade Guide

    Directory of Open Access Journals (Sweden)

    William J. O'Brien

    2012-12-01

    Full Text Available The purposes of this study are: (1 determine the color of the twenty shades in the Ivoclar’s Chromascop shade guide, (2 determine the color representation of the shade guide described as coverage error (CE, and (3 compare this shade guide with the Vita Classical and Bioform shade guides. The spectral data was collected using Beckman model DU reflectance spectrophotometer equipped with an integrating sphere. Commission International de l’Eclairage (CIE chromaticity coordinates were calculated using CIE illuminant C and 1931 observer data, then converted to CIE L*a*b* and Munsell notation. Each shade was spectrophotometrically compared to the published colors of 335 human teeth. The minimum CIE L*a*b* color difference was calculated for each tooth and the average of these color differences was defined as the CE. The measured colors of the Chromascop guide had a CIE L* range of 79.67 to 65.61, an a* range of -0.71 to 3.85, and a b* range of 14.58 to 27.69. The average CE of the Chromascop shade guide was 3.38. The Chromascop shade guide has similar colors and a CE compared with the Bioform and Vita Classical shade guides, but with some shades of higher red and yellow components.

  9. DESIGNING OF CONSTRUCTIVE SHADING DEVICES

    Directory of Open Access Journals (Sweden)

    V. L. Borukhava

    2016-01-01

    Full Text Available The paper shows how to determine dimensions of stationary horizontal (canopies and vertical (ribs shading devices in order to prevent penetration of normal beam solar radiation into the buildings during warm season of the year. While analyzing formulae for insolation rate equations for determination of dimensions of canopies and ribs which are perpendicular and inclined to the plane of intensively irradiated fenestrations orientated to the South, South-East, South-West, East and West have been obtained in the paper. Sloping canopies have the smallest dimensions. What is more, an angle of slope with regard to opening plane must correspond to elevation of sun station at an hour when there is a maximum specific heat flow rate of normal beam solar radiation. The paper considers an influence of canopies and ribs on transmission of diffuse solar radiation which along with normal beam solar radiation serves for creation of natural illumination. As follows from the analysis of formulae it is possible to make a conclusion about an inefficiency of vertical shading elements due to large rib dimensions and decrease in transmission of diffuse solar radiation. Minimum distances from fenestration reveal to the canopy have been determined for various orientations proceeding from the position that the opening must be maximally illuminated by normal beam solar radiation during the cold season of a year in order to reduce heat inputs for building heating. On the basis of dependence analysis we have come to a conclusion that it is appropriate to design stationary shading devices for fenestrations orientated only to the South and they must be sloping canopies. It is necessary to select glazing with a small index of solar factor for openings orientated to other corners of the Earth and reduction of solar radiation heat inputs.

  10. Visual and instrumental agreement in dental shade selection: three distinct observer populations and shade matching protocols.

    Science.gov (United States)

    Della Bona, Alvaro; Barrett, Allyson A; Rosa, Vinicius; Pinzetta, Caroline

    2009-02-01

    This study tested the hypothesis that the agreement between observer visual dental shade matches and instrumental shade identification is higher using the Vita 3D-Master (3D) shade guide than the Vita classical (VC) shade guide. Three populations selected shade matches: non-dental observers (GP) matched shade tabs-to-tabs and dental students (DS) and dentists (DD) matched an in vivo natural right upper central incisor (RUCI). All observers (n=600) used both shade guides (3D and VC) in two lighting conditions, cool white fluorescent lighting (CWF) and natural sunlight (NSL). The shade tabs and natural teeth were identified using an intra-oral spectrophotometer (Vita Easyshade) to determine the instrumental agreement with the visual shade selection. The percent visual-instrumental shade agreement (PVIA) was analyzed statistically considering: observer population, shade guide set, and lighting condition. A "substantial" intra-examiner agreement (k=0.76) was observed. The PVIA ranged from 12% (DS) for the 3D-NSL condition to 42% (DD) with the VC-CWF condition, which also resulted in the highest PVIA for GP (38.5%) and DS (35%). Results indicated that the GP with neither dental knowledge nor shade guide experience had a significantly higher PVIA using the VC rather than the 3D shade guide. Dentists demonstrated the highest PVIA (42%) for both lighting conditions and shade guides, thereby rejecting the study hypothesis. A significantly higher visual-instrumental shade agreement was demonstrated by the clinically experienced dentists (DD), regardless of shade guides and lighting conditions.

  11. Effect of dietary supplementation of l-tryptophan on thermal tolerance and oxygen consumption rate in Cirrhinus mrigala fingerlings under varied stocking density.

    Science.gov (United States)

    Tejpal, C S; Sumitha, E B; Pal, A K; Shivananda Murthy, H; Sahu, N P; Siddaiah, G M

    2014-04-01

    A 60 day feeding trial was conducted to study the effect of dietary l-tryptophan on thermal tolerance and oxygen consumption rate of freshwater fish, mrigala, Cirrhinus mrigala reared under ambient temperature at low and high stocking density. Four hundred eighty fingerlings were distributed into eight experimental groups. Four groups each of low density group (10 fishes/75L water) and higher density group (30 fishes/75L water) were fed a diet containing 0, 0.68, 1.36 or 2.72% l-tryptophan in the diet, thus forming eight experimental groups namely, Low density control (LC) (basal feed +0% l-tryptophan); LT1 (basal feed+0.68% l-tryptophan); LT2 (basal feed+1.36% l-tryptophan); LT3 (basal feed+2.72% l-tryptophan); high density control (HC) (basal feed+0% l-tryptophan); HT1 (basal feed+0.68% l-tryptophan); HT2 (basal feed+1.36% l-tryptophan); and HT3 (basal feed+2.72% l-tryptophan) were fed at 3% of the body weight. The test diets having crude protein 34.33±0.23 to 35.81±0.18% and lipid 423.49±1.76 to 425.85±0.31KCal/100g were prepared using purified ingredients. The possible role of dietary l-tryptophan on thermal tolerance and oxygen consumption rate was assessed in terms of critical thermal maxima (CTMax), critical thermal minima (CTMin), lethal thermal maxima (LTMax) and lethal thermal minima (LTMin). The CTMax, CTMin, LTMax and LTMin values were found to be significantly higher (ptryptophan in the diet significantly reduced the oxygen consumption rate in both the low density group (Y=-26.74x+222.4, r²=0.915) and the high density group (Y=-32.96x+296.5, r²=0.8923). Dietary supplementation of l-tryptophan at a level of 1.36% improved the thermal tolerance level and reduced the oxygen consumption rate in C. mrigala fingerlings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Dental shade matching using a digital camera.

    Science.gov (United States)

    Tam, W K; Lee, H J

    2012-12-01

    Digital cameras could be substitutes for contact-type instruments in shade selection and overcome their drawbacks. The images taken show morphology and color texture of teeth. A new method was proposed to compare the color of shade tabs taken by a digital camera using appropriate color features. Vita 3D-MASTER shade guide and Canon EOS 1100D digital camera were employed. Shade tab images were compared in two reference strategies. The color of tooth surface was presented by a content manually cropped out of the image. The content was divided into 10 × 2 blocks to encode the color distribution. Color features from commonly used color spaces were evaluated. The top n matches were selected when the least n shade distances between the shade tabs were attained. Using Sa*b* features, the top one accuracy was 0.87, where the feature S is defined in HSV color space, a* and b* features are defined in L*a*b* color space. This rate was higher than previous reports using contact-type instruments. The top three matching accuracy was 0.94. Sa*b* were suitable features for shade matching using a digital cameras in this study. Both the color and texture of the tooth surface could be presented by the proposed content-based descriptor. Clinical use of digital cameras in shade matching became possible. This in vitro study proposed a method for shade matching using digital cameras through the comparisons of the color patterns on the shade tab surfaces. The method overcame some drawbacks from the devices such as colorimeters or spectrophotometers. The results supported the use of digital cameras in shade matching. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Performance assessment of dental shade guides.

    Science.gov (United States)

    Paravina, Rade D

    2009-01-01

    The goal of this study was to evaluate influence of different shade guides and respective shade matching methods on shade matching results and to analyze user satisfaction with these products and methods. Eighty-eight pre-doctoral dental students completed the study. The color of four target shade tabs was matched using Toothguide 3D-Master (TG), Vitapan Classical (VC), and the prototype of Linearguide 3D-Master (LG). Shade matching was performed using color-corrected light source and 0/45 degrees optical geometry. An intra-oral spectrophotometer was used for color measurements of target tabs and shade guide tabs. Results for the first 10 best matching shade guide tabs were expressed as ranks (best match - 10 points to 10th match - 1 point). Participants also performed subjective evaluation of three shade guides/tab arrangements. Descriptive statistics were calculated. T-test and Wilcoxon signed rank test were used for statistical analysis of the data (alpha=0.05). The best shade matching results were achieved using LG, followed by VC and TG, and the ranks were 9.1+/-1.2, 8.8+/-1.9 and 8.4+/-2.8. Differences in DeltaE* values for the first 10 matches between TG/LG (4.5+/-1.8) and VC (6.2+/-2.2) were found to be statistically significant (p3D-Master enabled better shade matching results compared to Toothguide 3D-Master (p3D-Master shade guides exhibited significantly smaller DeltaE* values for the first 10 matches compared to Vitapan Classical (p3D-Master was superior in a subjective evaluation compared to Toothguide 3D-Master and Vitapan Classical (p<0.001).

  14. A continent-wide analysis of the shade requirements of red and western grey kangaroos.

    Science.gov (United States)

    Roberts, J A; Coulson, G; Munn, A J; Kearney, M R

    2016-01-01

    Foraging time may be constrained by a suite of phenomena including weather, which can restrict a species' activity and energy intake. This is recognized as pivotal for many species whose distributions are known to correlate with climate, including kangaroos, although such impacts are rarely quantified. We explore how differences in shade seeking, a thermoregulatory behavior, of 2 closely-related kangaroo species, Macropus rufus (red kangaroos) and M. fuliginosus (western grey kangaroos), might reflect differences in their distributions across Australia. We observed foraging and shade-seeking behavior in the field and, together with local weather observations, calculated threshold radiant temperatures (based on solar and infrared radiant heat loads) over which the kangaroos retreated to shade. We apply these calculated tolerance thresholds to hourly microclimatic estimates derived from daily-gridded weather data to predict activity constraints across the Australian continent over a 10-year period. M. fuliginosus spent more time than M. rufus in the shade (7.6 ± 0.7 h versus 6.4 ± 0.9 h) and more time foraging (11.8 ± 0.5 h vs. 10.0 ± 0.6 h), although total time resting was equivalent (∼8.2 h). M. rufus tolerated 19°C higher radiant temperatures than M. fuliginosus (89°C versus 70°C radiant temperature). Across Australia, we predicted M. fuliginosus to be more restricted to shade than M. rufus, with higher absolute shade requirements farther north. These results corroborate previous findings that M. rufus is more adept at dealing with heat than M. fuliginosus and indicate that M. rufus is less dependent on shade on a continental scale.

  15. 100-Meter Resolution Grayscale Shaded Relief of Hawaii - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Grayscale Shaded Relief of Hawaii map layer is a 100-meter resolution grayscale shaded relief image of Hawaii, in an Albers Equal-Area Conic projection. Shaded...

  16. 100-Meter Resolution Grayscale Shaded Relief of Alaska - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Grayscale Shaded Relief of Alaska map layer is a 100-meter resolution grayscale shaded relief image of Alaska, in an Albers Equal-Area Conic projection. Shaded...

  17. Daylight Adaptive Shading Using Parametric Camshaft Mechanism for SOHO in Jakarta

    Science.gov (United States)

    Utama Sjarifudin, Firza; Justina, Laurensia

    2014-03-01

    This research analyzes SOHO (Small Office Home Office) which can adjust to the need of visual comfort for the users through natural daylighting and also can be adapted to standard requirements of 14 creative industry workspace in Jakartas. The method of the research is by simulating the SOHO unit with variation of shading opening angles in order to adapt to each unit. Analysis done to every shading opening angle to get the appropriate daylight intensity level which support the work activities in every unit for the whole day. In order for the shading to be able to adapt to the changing daylight condition, previously developed parametric camshaft mechanism was used. The study found that the visual comfort for SOHO with creative industries workers in Jakarta can be achieve by varying the shading opening angles between 15-75°.

  18. ORIGINAL ARTICLE Shade Tree Selection and Management ...

    African Journals Online (AJOL)

    wonde

    Abstract. There is a traditional practice of forest management in coffee producing communities in. Ethiopian moist Afromontane forests to increase coffee production. The practice involves removal of big canopy trees with excessive shade and selectively retaining specific tree species as preferred shade trees. This study was ...

  19. Physiological reactions in goat breeds maintained under shade, sun and partially shaded areas

    Directory of Open Access Journals (Sweden)

    Luís Fernando Dias Medeiros

    2015-12-01

    Full Text Available ABSTRACT. Medeiros L.F.D., Rodrigues V.C., Vieira D.H., Souza S.L.G. de, Neto O.C., Figueiredo N. de, Pinto C.F.D., Miranda A.L. & Violento C.B. [Physiological reactions in goat breeds maintained under shade, sun and partially shaded areas.] Reações fisiológicas de cabras em diferentes ambientes e coeficiente de tolerância ao calor em cabritos. Revista Brasileira de Medicina Veterinária, 37(4:286-296, 2015. Departamento de Reprodução e Avaliação Animal, Instituto de Zootecnia, Universidade Federal Rural do Rio de Janeiro, BR 465 Km 7, Seropédica, RJ 23851-970, Brasil. E-mail: diasmedeiros@yahoo.com.br The experiment was carried out to measure the effects of thermal stress on the rectal temperature (RT and respiratory frequency (RF, in animals of Boer and Saanen breeds, under the conditions of hot and humid climate of city of Rio de Janeiro, Baixada Fluminense, South East Region of Brazil; also the heat tolerance coefficient (HTC of Amakiri e Funcho was applied on pure and crossbreeds kids. The goats were divided into three groups, each group consisting of four females from each breed group. Each group was subjected to different surroundings, constituted by three experimental treatment: treatment A, with a sun protected enclosed area; treatment B, a sun exposed area without covering; and treatment C, area with a 50% covered section and a 50% sun exposed area, which permitted free circulation of the goats. A Balanced Latin Square was used. The RT and RF of the goats, in the afternoon periods (l5h00, were higher, than in the morning periods (09h00. The animals kept in the sun presented much higher results, especially in the afternoon periods, than the animals in the other two confinement areas. There were no differences in the RT and RF of the groups maintained in the shade or in partially covered area. There were differences in the RT and RF measurements between the two breeds, in the morning periods and in the afternoon periods

  20. Determination of VITA Classical shades with the 3D-Master shade guide.

    Science.gov (United States)

    Hassel, Alexander J; Zenthöfer, Andreas; Corcodel, Nicoleta; Hildenbrandt, Achim; Reinelt, Gerhard; Wiesberg, Stefan

    2013-01-01

    Because of its good matching performance the VITA 3D-Master shade guide (3D) is frequently used for determination of tooth color. Numerous composites/ceramics are, however, available in VITA Classical (VC) shades only. The objective of this study was to investigate the possibility of performing a shade match with 3D Master and converting this result via a table in a VC shade (indirect method) without this resulting in an apparent inferior shade matching in comparison with direct shade matching with the VC. Experiments were performed with an artificial, computer-generated tooth color space. Conversion tables were generated by calculating the color difference (ΔE) between a 3D shade and the closest VC shade (simple conversion table) and with the aid of optimization procedures. Statistical differences between the direct and indirect methods and between the indirect methods were assessed by use of a U-test. Median ΔE was 2.38 for direct matching with the VC and 2.86 for indirect matching by use of a simple conversion table (p < 0.01). Optimized tables performed slightly better (median ΔE = 2.81). Within the limitations of the study, it is usually possible to determine tooth color with the 3D and convert it, via a table, into a VC shade without adding a clinically apparent error to the direct shade match with the VC.

  1. Influence of personality on tooth shade selection.

    Science.gov (United States)

    Haralur, Satheesh B; Al-Shehri, Khalid Saleh; Assiri, Hassan Mohammed; Al-Qahtani, Mushabab AbdulRahman

    2016-01-01

    The harmonious shade matching of restorations with adjacent natural teeth is a prerequisite for a successful esthetic restoration. Color is a combined effect of the physical properties of an object, the light source, and the perception of the observer. The interpretation of color is influenced by both the physiological and psychological health of an individual. It is critical to understand the influence of an individual's psychological state on the shade selection procedure to achieve better shade matching and post-treatment patient counseling. The aim of this study was to evaluate the influence of personality on tooth shade selection capability. Two porcelain fused to metal (PFM) discs were fabricated. A reference shade was determined using a spectrophotometer (Vita Easyshade, Vita). The personalities of volunteers were identified using a Myers- Briggs Type Indicator (MBTI) questionnaire. The volunteers visually identified the shade of the two PFM discs under a controlled light source. The mean color difference was determined between the visual and the spectrophotometer values. The data thus obtained was statistically analyzed with Kruskal-Wallis and post-hoc comparison tests to ascertain the difference between the groups. The groups that performed better in tooth shade selection were ENTJ (2.923 ± 2.36), ISTJ (3.086 ± 2.56), ENFJ (3.197 ± 2.936), and ESTJ (3.431± 2.78). The groups INTP (9.383 ± 3.30), ISTP (9.133 ± 3.44), ISFP (8.737 ± 2.81), and INTJ (8.480 ± 3.35) showed poor tooth shade selection ability. The Kruskal- Wallis test showed lower mean rank for group ENTJ (89.75), followed by ISTJ (92.25), and ENFJ (94.80). Within the limitations of this study, it was concluded that there was a statistically significant difference between the different personalities with regard to tooth shade selection ability.

  2. Guiana Highlands, Shaded Relief and Colored Height

    Science.gov (United States)

    2003-01-01

    [figure removed for brevity, see original site] These two images show exactly the same area in South America, the Guiana Highlands straddling the borders of Venezuela, Guyana and Brazil. The image on the left was created using the best global topographic data set previously available, the U.S. Geological Survey's GTOPO30. In contrast, the image on the right was generated with a new data set recently released by the Shuttle Radar Topography Mission (SRTM) called SRTM30, which represents a significant improvement in our knowledge of the topography of much of the world.GTOPO30, with a resolution of about 928 meters (1496 feet), was developed over a three-year period and published in 1996, and since then has been the primary source of digital elevation data for scientists and analysts involved in global studies. However, since it was compiled from a number of different map sources with varying attributes, the data for some parts of the globe were inconsistent or of low quality.The SRTM data, on the other hand, were collected within a ten-day period using the same instrument in a uniform fashion, and were processed into elevation data using consistent processing techniques. Thus SRTM30 provides a new resource of uniform quality for all parts of the Earth, and since the data, which have an intrinsic resolution of about 30 meters, were averaged and resampled to match the GTOPO30 sample spacing and format, and can be used by the same computer software without modification.The Guiana Highlands are part of the Guyana Shield, which lies in northeast South America and represent one of the oldest land surfaces in the world. Chemical weathering over many millions of years has created a landscape of flat-topped table mountains with dramatic, steep cliffs with a large number of spectacular waterfalls. For example Angel Falls, at 979 meters the highest waterfall in the world, plunges from Auyan Tebuy, part of a mesa of the type that may have been the inspiration for Arthur Conan

  3. Lake Bathymetric DEM Shaded Relief Image

    Data.gov (United States)

    Minnesota Department of Natural Resources — Geo-referenced, shaded relief image of lake bathymetry classified at 5-foot depth intervals. This dataset has a cell resolution of 5 meters (occasionally 10m) as...

  4. Shaded Relief of Minnesota Elevation - Color

    Data.gov (United States)

    Minnesota Department of Natural Resources — This file is a product of a shaded relief process on the 30 meter resolution Digital Elevation Model data (dem30im3). This image was created using a custom AML...

  5. Shaded Relief of Minnesota Elevation - Black & White

    Data.gov (United States)

    Minnesota Department of Natural Resources — This file is a product of a shaded relief process on the 30 meter resolution Digital Elevation Model data (dem30im3). This image was created using a custom AML...

  6. Power producing sun shades; Elproducerende solafskaermninger

    Energy Technology Data Exchange (ETDEWEB)

    Johnsen, K.; Soerensen, Henrik; Katic, I.; Schmidt-Petersen, H.; AAroe, D.

    2012-01-15

    Integrating photovoltaics into sun shades takes advantage of the best opportunities to capture and utilize solar energy when the shades are most needed to shield users from solar radiation. The report describes results of a development project for solar shading in the form of broad, horizontal and rotating lamellae with solar cells and an integrated control function that simultaneously is optimized based on energy consumption and thermal and visual indoor climate. The project idea was to meet the needs for effective sun protection in the present office, commercial and public buildings, where glass facades are dominant. The conclusion of the development project is that it rarely would be optimal to integrate solar cells into movable shades. This will normally only be relevant in cases where it is justified by architectural considerations. (LN)

  7. The Influence of Dental Shade Guides and Experience on the Accuracy of Shade Matching.

    Science.gov (United States)

    Nakhaei, Mohammadreza; Ghanbarzadeh, Jalil; Amirinejad, Sahar; Alavi, Samin; Rajatihaghi, Hamidreza

    2016-01-01

    There is limited and inconsistent information on some factors affecting visual shade selection. The aim of this study was to evaluate the influence of shade guide type and professional experience on shade-matching results. Thirty Dental students (DS), 30 General dentists (GDs) and 30 Dental specialists (S) participated in this study. The participants were asked to match six target tabs using two dental shade guides: Vitapan Classical (VC) and Vitapan 3D-Master (3D). An intraoral spectrophotometer was used for color measurement of target tabs and selected tabs. The color difference (ΔE) values between the target tab and selected tab were calculated. Data were analyzed using analysis of variance (ANOVA) and paired f-test (α = 0.05). Results of the first five best matches for each target tab were expressed as ΔE1 to ΔE5. Differences in the mean values of ΔE1 to ΔE5 between VC and 3D were compared using descriptive statistics. There were no significant differences among the three participating groups in ΔE values when the 3D was used (p = 0.389). However, significant differences were found with VC (p 3D-Master shade guide was used. Compared with Vitapan Classical shade guide, use of the Vitapan 3D-Master shade guide improves shade-matching results. Color, Experience, Gender, Selection, Shade, Visual. How to cite this article: Nakhaei M, Ghanbarzadeh J, Amirinejad S, Alavi S, Rajatihaghi H. The Influence of Dental Shade Guides and Experience on the Accuracy of Shade Matching. J Contemp Dent Pract 2016;17(1):22-26. Source of support: This study was supported by a grant (No. 920903) from the Vice Chancellor for Research of Mashhad University of Medical Sciences. The results presented here are based on undergraduate thesis (No. 2686) submitted to Mashhad School of Dentistry and Dental Research Center. None.

  8. Reliability and accuracy of four dental shade-matching devices.

    Science.gov (United States)

    Kim-Pusateri, Seungyee; Brewer, Jane D; Davis, Elaine L; Wee, Alvin G

    2009-03-01

    There are several electronic shade-matching instruments available for clinical use, but the reliability and accuracy of these instruments have not been thoroughly investigated. The purpose of this in vitro study was to evaluate the reliability and accuracy of 4 dental shade-matching instruments in a standardized environment. Four shade-matching devices were tested: SpectroShade, ShadeVision, VITA Easyshade, and ShadeScan. Color measurements were made of 3 commercial shade guides (Vitapan Classical, Vitapan 3D-Master, and Chromascop). Shade tabs were placed in the middle of a gingival matrix (Shofu GUMY) with shade tabs of the same nominal shade from additional shade guides placed on both sides. Measurements were made of the central region of the shade tab positioned inside a black box. For the reliability assessment, each shade tab from each of the 3 shade guide types was measured 10 times. For the accuracy assessment, each shade tab from 10 guides of each of the 3 types evaluated was measured once. Differences in reliability and accuracy were evaluated using the Standard Normal z test (2 sided) (alpha=.05) with Bonferroni correction. Reliability of devices was as follows: ShadeVision, 99.0%; SpectroShade, 96.9%; VITA Easyshade, 96.4%; and ShadeScan, 87.4%. A significant difference in reliability was found between ShadeVision and ShadeScan (P=.008). All other comparisons showed similar reliability. Accuracy of devices was as follows: VITA Easyshade, 92.6%; ShadeVision, 84.8%; SpectroShade, 80.2%; and ShadeScan, 66.8%. Significant differences in accuracy were found between all device pairs (P<.001) for all comparisons except for SpectroShade versus ShadeVision (P=.033). Most devices had similar high reliability (over 96%), indicating predictable shade values from repeated measurements. However, there was more variability in accuracy among devices (67-93%), and differences in accuracy were seen with most device comparisons.

  9. Does triacylglycerol (TAG) serve a photoprotective function in plant leaves? An examination of leaf lipids under shading and drought.

    Science.gov (United States)

    Marchin, Renée M; Turnbull, Tarryn L; Deheinzelin, Audrey I; Adams, Mark A

    2017-11-01

    Plant survival in many ecosystems requires tolerance of large radiation loads, unreliable water supply and suboptimal soil fertility. We hypothesized that increased production of neutral lipids (triacylglycerols, TAGs) in plant leaves is a mechanism for dissipating excess radiation energy. In a greenhouse experiment, we combined drought and shade treatments and examined responses among four species differing in life form, habitat, and drought- and shade-tolerance. We also present a lipid extraction protocol suitable for sclerophyllous leaves of native Australian trees (e.g. Acacia, Eucalyptus). Fluorescence measurements indicated that plants exposed to full sunlight experienced mild photoinhibition during our experiment. Accumulation of TAGs did not follow photosynthetic capacity, but instead, TAG concentration increased with non-photochemical quenching. This suggests that plants under oxidative stress may increase biosynthesis of TAGs. Moderate drought stress resulted in a 60% reduction in TAG concentration in wheat (Triticum aestivum). Shading had no effect on TAGs, but increased concentrations of polar lipids in leaves; for example, acclimation to shade in Austrodanthonia spp., a native Australian grass, resulted in a 60% increase in associated polar lipids and higher foliar chlorophyll concentrations. Shading also reduced the digalactosyldiacylglycerol:monogalactosyldiacylglycerol (DGDG:MGDG) ratio in leaves, with a corresponding increase in the degree of unsaturation and thus fluidity of thylakoid membranes of chloroplasts. Our results suggest that prevention of photodamage may be coordinated with accumulation of TAGs, although further research is required to determine if TAGs serve a photoprotective function in plant leaves. © 2017 Scandinavian Plant Physiology Society.

  10. Color match of two different ceramic systems to selected shades of one shade guide.

    Science.gov (United States)

    Corciolani, Gabriele; Vichi, Alessandro; Louca, Chris; Ferrari, Marco

    2011-03-01

    There are no consistent indications given by dental manufacturers on how to layer ceramics to achieve a color match to a shade selected from a dental shade guide. The technique for ceramic layering relies primarily on the skill and experience of ceramists and is not easily predictable. The purpose of this study was to evaluate, using a clinical spectrophotometer, the ability to color match shades selected with the 3D-Master shade guide using 2 different ceramic systems. Two ceramic systems were selected for this study, the VITA Omega 900 and VITA VM 13. For both systems, shades 2M3, 3M2, 4M2 of the VITA 3D-Master shade guide were selected. Thirty ceramic discs, 15 mm in diameter, were fabricated with different layer thickness ratios of opaque dentin, dentin, and enamel, maintaining a constant overall thickness. A clinical spectrophotometer (VITA Easyshade) was used for color comparison. The measured ΔE values were statistically analyzed with a 3-way ANOVA and the Tukey HSD test (α=.05). The 3-way ANOVA showed that the ceramic system (P3D-Master shade guide to be within the limits for clinical acceptability (ΔE≤ 3.3). VM 13 showed a statistically better color match. The layering scheme influenced the definitive color of the restoration. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  11. Experimental and Numerical Analysis of Modelling of Solar Shading

    DEFF Research Database (Denmark)

    Winther, Frederik Vildbrad; Liu, Mingzhe; Heiselberg, Per Kvols

    2017-01-01

    The use of solar shading in future low energy office buildings is essential for minimizing energy consumption for building services, while maintaining thermal conditions. Implementing solar shading technologies in energy calculations and thermal building simulation programs is essential in order...

  12. Bathymetric Shaded Relief of North America - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Bathymetric Shaded Relief of North America map layer shows depth ranges using colors, with relief enhanced by shading. The image was derived from the National...

  13. USGS Hill Shade Base Map Service from The National Map

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — USGS Hill Shade (or Shaded Relief) is a tile cache base map created from the National Elevation Dataset (NED), a seamless dataset of best available raster elevation...

  14. Topographic and Bathymetric Shaded Relief of North America - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Topographic and Bathymetric Shaded Relief of North America map layer shows depth and elevation ranges using colors, with relief enhanced by shading. The image...

  15. The effect of colour defective vision on shade matching accuracy.

    Science.gov (United States)

    Ethell, J; Jarad, F D; Youngson, C C

    2006-09-01

    One hundred and forty one male dental students and staff were screened for colour-defective vision. Ten colour-defective and 20 non colour-defective subjects then carried out a shade matching exercise using nine selected shades and another matched, shade tab (to test for consistency) from Vita shade guides. All shade matching took place under standard lighting conditions. Each subject also completed a short questionnaire relevant to shade matching. There were no significant differences found between colour-defective and non colour-defective subjects in shade matching abilities. Although both subject groups were similar in their shade matching abilities, individuals with colour defective vision perceived it to be a slightly more difficult exercise.

  16. 100-Meter Resolution Color Shaded Relief of Hawaii - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Color Shaded Relief of Hawaii map layer is a 100-meter resolution color-sliced elevation image of Hawaii, with relief shading added to accentuate terrain...

  17. 100-Meter Resolution Color Shaded Relief of Alaska - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Color Shaded Relief of Alaska map layer is a 100-meter resolution color-sliced elevation image of Alaska, with relief shading added to accentuate terrain...

  18. Experimental and Numerical Analysis of Modelling of Solar Shading

    DEFF Research Database (Denmark)

    Winther, Frederik Vildbrad; Liu, Mingzhe; Heiselberg, Per

    2017-01-01

    The use of solar shading in future low energy office buildings is essential for minimizing energy consumption for building services, while maintaining thermal conditions. Implementing solar shading technologies in energy calculations and thermal building simulation programs is essential in order...... to demonstrate the effect of adaptive solar shading. In order to document the benefits of the shading technology, the description of the shading device in the thermal building simulation software must be described at a reasonably accurate level, related to the specific solar shading device. This research...... presents different approaches for modeling solar shading devices, demonstrating the level of accuracy in relation to measurement conducted in a full-scale façade test facility at Aalborg University. The research bridges the gap between increased complexity of solar shading technologies and the use...

  19. Solar shading control strategy for office buildings in cold climate

    DEFF Research Database (Denmark)

    Røseth Karlsen, Line; Heiselberg, Per Kvols; Bryn, Ida

    2016-01-01

    Highlights •Solar shading control strategy for office buildings in cold climate is developed. •Satisfying energy and indoor environmental performance is confirmed. •Importance of integrated evaluations when selecting shading strategy is illustrated.......Highlights •Solar shading control strategy for office buildings in cold climate is developed. •Satisfying energy and indoor environmental performance is confirmed. •Importance of integrated evaluations when selecting shading strategy is illustrated....

  20. Net herbage accumulation rate and crude protein content of Urochloa brizantha cultivars under shade intensities

    Directory of Open Access Journals (Sweden)

    Paulo Roberto de Lima Meirelles

    2013-12-01

    Full Text Available The use of silvopastoral systems is a sustainable alternative for animal production in various regions of the Brazil. However to obtain satisfactory results in these systems, the selection of forage species that grows well in the shade should be done. The tolerance of plants to light restriction and the correctly choice of species, considering good nutritional values for these conditions has great importance. The study of artificial shading for forage production helps the clarification of issues related to the behavior of plants under reduced light prior to use in integrations with forests. The aim of the study was to evaluate the net herbage accumulation rate of forage (HAR and crude protein (CP of Urochloa brizantha cultivars (Marandu and Piatã under natural light and shading of 30 and 60%. The experiment was conducted at FMVZ - UNESP, Botucatu. The experimental design was a randomized block in factorial arrangement 3 x 2 (three shading levels: 0, 30 and 60%, two cultivars: Marandu and Piatã with three replications and repeated measures (3 cuts. Sample collection occurred when the cultivars reached 35 cm in height. The treatments with shading showed lower cutting intervals as compared to those subjected to full sunlight, because they have reached in a shorter time to time as determined cut-off criterion (mean of 37, 45 and 61 days for reduction of 60%, reduction of 30% and full sun. Significant effects (P<0.05 interaction cultivar x shade x cut on the net herbage accumulation rate (HAR. Most HAR (P<0.05 was observed for cv. Marandu 60% reduction in lightness (127 kg/ha/day due to increased production of stem during the first growing cycle. The lower HAR also occurred to Marandu, but under natural light in the third cut (34 kg/ha/day due to adverse weather conditions during the growth interval. The shadow effect and the cutting (P<0.05 affected CP. The percentage of CP on cultivars showed the highest values (average value of 9.27% in 60

  1. Young Women's Perceptions of the Relationship in Fifty Shades of Grey.

    Science.gov (United States)

    Bonomi, Amy E; Nichols, Emily M; Carotta, Christin L; Kiuchi, Yuya; Perry, Samantha

    2016-02-01

    Millions of women are interacting with Fifty Shades of Grey-a best-selling novel and film. Yet, to date, no social science study has been undertaken to examine women's perceptions of the Fifty Shades relationship narrative in its film adaptation-what they deem appealing, what they deem unappealing, and what they would welcome or resist in their own relationship. In the present study, we used focus groups to examine women's perceptions of the relationship patterns in the Fifty Shades of Grey film. Focus groups were conducted with 35 young adult women (randomly sampled from the registrar's office of a large Midwestern university) immediately after watching the Fifty Shades film with the study team at a local theater within two days of the film's release. Seven semistructured questions concentrating on reactions to the relationship patterns between Christian Grey and Anastasia Steele depicted in the Fifty Shades film were asked, including general reactions, appealing and unappealing characteristics, romantic and dangerous elements, and aspects that participants would tolerate (or not tolerate) in their own relationships. While participants assessed parts of the relationship between Christian and Anastasia as exciting and romantic, they consistently indicated an unappealing lack of health in the relationship. Participants expressed grave concerns over Christian's stalking, controlling, manipulative, and emotionally abusive behavior, anger in sexual interactions, and neglect of Anastasia's needs. At the same time, they sympathized with and rationalized Christian's behaviors as a function of his personality, needs, and abilities. A small contingent implicated Anastasia in the unhealthy relationship process, whereas a broader majority of participants highlighted the challenges with trying to "speak up" in an unhealthy relationship like Christian and Anastasia's. When asked where participants would draw the line in their own relationship, participants indicated they would

  2. Effect of Dominant Shade Trees on Coffee Production in Manasibu ...

    African Journals Online (AJOL)

    Effect of shade trees species on coffee production in Manasibu district, West Ethiopia was assessed by the current study. It was aimed to (i) identify the most suitable dominant shade tree species for coffee production; (ii) assess the status of coffee production under different dominant coffee shade trees and unshaded areas ...

  3. 21 CFR 872.3690 - Tooth shade resin material.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tooth shade resin material. 872.3690 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3690 Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A glycidyl...

  4. Effects of street tree shade on asphalt concrete pavement performance

    Science.gov (United States)

    E.G. McPherson; J. Muchnick

    2005-01-01

    Forty-eight street segments were paired into 24 high-and low-shade pairs in Modesto, California, U.S. Field data were collected to calculate a Pavement Condition Index (PCI) and Tree Shade Index (TSI) for each segment. Statistical analyses found that greater PCI was associated with greater TSI, indicating that tree shade was partially responsible for reduced pavement...

  5. Influence of Shading on Cooling Energy Demand

    Science.gov (United States)

    Rabczak, Sławomir; Bukowska, Maria; Proszak-Miąsik, Danuta; Nowak, Krzysztof

    2017-10-01

    The article presents an analysis of the building cooling load taking into account the variability of the factors affecting the size of the heat gains. In order to minimize the demand for cooling, the effect of shading elements installed on the outside on the windows and its effect on size of the cooling capacity of air conditioning system for the building has been estimated. Multivariate building cooling load calculations to determine the size of the reduction in cooling demand has derived. Determination of heat gain from the sun is laborious, but gives a result which reflects the influence of the surface transparent partitions, devices used as sunscreen and its location on the building envelope in relation to the world, as well as to the internal heat gains has great attention in obtained calculation. In this study, included in the balance sheet of solar heat gains are defined in three different shading of windows. Calculating the total demand cooling is made for variants assuming 0% shading baffles transparent, 50% shading baffles transparent external shutters at an angle of 45 °, 100% shading baffles transparent hours 12 from the N and E and from 12 from the S and W of the outer slat blinds. The calculation of the average hourly cooling load was taken into account the option assuming the hypothetical possibility of default by up to 10% of the time assumed the cooling season temperatures in the rooms. To reduce the consumption of electricity energy in the cooling system of the smallest variant identified the need for the power supply for the operation of the cooling system. Also assessed the financial benefits of the temporary default of comfort.

  6. EXAMINING THE PREFERENCE FOR SHADE STRUCTURES IN FARMED GREEN SEA TURTLES (CHELONIA MYDAS) AND SHADE'S EFFECT ON GROWTH AND TEMPERATURES.

    Science.gov (United States)

    Keller, Martha; Mustin, Walter

    2017-03-01

    The Cayman Turtle Farm raises thousands of green sea turtles ( Chelonia mydas ) annually under aquaculture conditions. Historically, the turtles have been raised in tanks without routine access to a shade structure. The purpose of this study was to determine the effects of adding a shade structure on curved carapace length (CCL) and weight gain of green sea turtles. In addition, water and cloacal temperatures were compared across treatment groups and shade cover preferences observed. Ninety turtles were split equally into three treatment groups for this 8-wk study. In the first group turtles were kept in tanks in full sun, the second group in half-shaded tanks, and the third group in tanks completely covered with shade cloth. Time-lapse cameras mounted above half-shaded tanks were used to determine turtle shade structure preferences throughout the day. There were no differences in CCL among treatment groups. Significant increases in weights were noted in turtles kept in full sun and half-shaded tanks versus the fully shaded tanks. Significantly higher water and cloacal turtle temperatures were noted in the full-sun tank compared with the half-shaded or completely shaded tanks. A significantly lower number of turtles was observed in the sun in the half-shaded tanks, indicating a possible preference by turtles for a shade structure. Results suggest that providing shade structures for sea turtles results in a significant decrease in both overall water temperature as well as a reduction in maximum high daily temperatures. Results also suggest that turtles exhibit a preference for shade structures when it is provided as an option. From these results, we recommend that a shade structure be provided when housing green sea turtles in outdoor enclosures.

  7. Interactive effects of spectral shading and mechanical stress on the expression and costs of shade avoidance.

    Science.gov (United States)

    Anten, Niels P R; von Wettberg, Eric J; Pawlowski, Marcin; Huber, Heidrun

    2009-02-01

    The interacting effects of different environmental cues in determining a plant's phenotype and performance are poorly understood aspects of phenotypic plasticity. We examined the interacting effects of shading and mechanical stress (MS) on growth, reproduction, and mechanical stability. We subjected 10 grassland genotypes and 10 forest genotypes of Impatiens capensis to two levels of spectral shading and two levels of MS. Shade induced the production of taller, thinner internodes, but this response was inhibited by MS. This interactive effect was stronger in the grassland genotypes than in the forest genotypes, indicating that shade avoidance can be suppressed by MS and that the degree of this suppression differs between habitats. Among genotypes, greater plasticity in shade-induced internode elongation resulted in a larger reduction in the ability of plants to carry their own weight. This suggests that the occurrence of mechanical constraints may strongly contribute to the selection against shade-induced elongation responses in forest understory genotypes. Our results show that combined responses to different environmental cues can result in a fine-tuning of phenotypic expression by plants by maintaining the potential to strongly respond to single environmental cues but also by preventing potential future costs resulting from poor adaptation to other stresses.

  8. Analysis of internal shading degree to a prototype of dynamics photovoltaic greenhouse through simulation software

    Directory of Open Access Journals (Sweden)

    Alvaro Marucci

    2015-12-01

    Full Text Available In recent years the use of photovoltaic panels as cover materials for greenhouses developed a great interest due to the state’s incentives obtainable by such applications. Shading caused by these elements inside the structure appears to be often too much for the normal development of agricultural activity. In this study it was analyzed the behaviour of shading caused by the photovoltaic panels inside a prototype of dynamic photovoltaic greenhouse whose particularity lies in the possibility of rotation of the panels along the longitudinal axis. The panels’ rotation allows varying shading degree in function of some parameters such as latitude and the different solar angles. In order to avoid any reflection losses due to imperfect inclination of the photovoltaic panels, 24 highly reflective aluminium mirrors were prepared with the objective of recovering the portion of solar radiation otherwise lost by reflection. For the study it was used the simulation software Autodesk® Ecotect® Analysis which allows to analyse the path of the shadows during the day and throughout the year for any latitude considered. For this study it was analyzed shading with the panels in a horizontal position. It was also analyzed the evolution of the percentage of shading simulating different latitudes. The results obtained show a great variation of the shading degree inside the structure during a single day and during the year. We can conclude that integrating this analysis with the energy balance it is possible to study the behaviour of photovoltaic greenhouses in order to integrate the energy production from renewable energy sources and agricultural production.

  9. Native Environment Modulates Leaf Size and Response to Simulated Foliar Shade across Wild Tomato Species

    Science.gov (United States)

    Filiault, Daniele L.; Kumar, Ravi; Jiménez-Gómez, José M.; Schrager, Amanda V.; Park, Daniel S.; Peng, Jie; Sinha, Neelima R.; Maloof, Julin N.

    2012-01-01

    The laminae of leaves optimize photosynthetic rates by serving as a platform for both light capture and gas exchange, while minimizing water losses associated with thermoregulation and transpiration. Many have speculated that plants maximize photosynthetic output and minimize associated costs through leaf size, complexity, and shape, but a unifying theory linking the plethora of observed leaf forms with the environment remains elusive. Additionally, the leaf itself is a plastic structure, responsive to its surroundings, further complicating the relationship. Despite extensive knowledge of the genetic mechanisms underlying angiosperm leaf development, little is known about how phenotypic plasticity and selective pressures converge to create the diversity of leaf shapes and sizes across lineages. Here, we use wild tomato accessions, collected from locales with diverse levels of foliar shade, temperature, and precipitation, as a model to assay the extent of shade avoidance in leaf traits and the degree to which these leaf traits correlate with environmental factors. We find that leaf size is correlated with measures of foliar shade across the wild tomato species sampled and that leaf size and serration correlate in a species-dependent fashion with temperature and precipitation. We use far-red induced changes in leaf length as a proxy measure of the shade avoidance response, and find that shade avoidance in leaves negatively correlates with the level of foliar shade recorded at the point of origin of an accession. The direction and magnitude of these correlations varies across the leaf series, suggesting that heterochronic and/or ontogenic programs are a mechanism by which selective pressures can alter leaf size and form. This study highlights the value of wild tomato accessions for studies of both morphological and light-regulated development of compound leaves, and promises to be useful in the future identification of genes regulating potentially adaptive plastic

  10. Ceramic materials for porcelain veneers: part II. Effect of material, shade, and thickness on translucency.

    Science.gov (United States)

    Barizon, Karine T L; Bergeron, Cathia; Vargas, Marcos A; Qian, Fang; Cobb, Deborah S; Gratton, David G; Geraldeli, Saulo

    2014-10-01

    Information regarding the differences in translucency among new ceramic systems is lacking. The purpose of this study was to compare the relative translucency of the different types of ceramic systems indicated for porcelain veneers and to evaluate the effect of shade and thickness on translucency. Disk specimens 13 mm in diameter and 0.7-mm thick were fabricated for the following 9 materials (n=5): VITA VM9, IPS Empress Esthetic, VITA PM9, Vitablocks Mark II, Kavo Everest G-Blank, IPS Empress CAD, IPS e.max CAD, IPS e.maxPress, and Lava Zirconia. VITA VM9 served as the positive control and Lava as the negative control. The disks were fabricated with the shade that corresponds to A1. For IPS e.maxPress, additional disks were made with different shades (BL2, BL4, A1, B1, O1, O2, V1, V2, V3), thickness (0.3 mm), and translucencies (high translucency, low translucency). Color coordinates (CIE L∗ a∗ b∗) were measured with a tristimulus colorimeter. The translucency parameter was calculated from the color difference of the material on a black versus a white background. One-way ANOVA, the post hoc Tukey honestly significant difference, and the Ryan-Einot-Gabriel-Welsch multiple range tests were used to analyze the data (α=.05). Statistically significant differences in the translucency parameter were found among porcelains (PPM9, Empress Esthetic>Empress CAD>Mark II, Everest, e.max CAD>e.max Press>Lava. Significant differences also were noted when different shades and thickness were compared (Pveneers present varying degrees of translucency. The thickness and shade of lithium disilicate ceramic affect its translucency. Shade affects translucency parameter less than thickness. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  11. Native environment modulates leaf size and response to simulated foliar shade across wild tomato species.

    Directory of Open Access Journals (Sweden)

    Daniel H Chitwood

    Full Text Available The laminae of leaves optimize photosynthetic rates by serving as a platform for both light capture and gas exchange, while minimizing water losses associated with thermoregulation and transpiration. Many have speculated that plants maximize photosynthetic output and minimize associated costs through leaf size, complexity, and shape, but a unifying theory linking the plethora of observed leaf forms with the environment remains elusive. Additionally, the leaf itself is a plastic structure, responsive to its surroundings, further complicating the relationship. Despite extensive knowledge of the genetic mechanisms underlying angiosperm leaf development, little is known about how phenotypic plasticity and selective pressures converge to create the diversity of leaf shapes and sizes across lineages. Here, we use wild tomato accessions, collected from locales with diverse levels of foliar shade, temperature, and precipitation, as a model to assay the extent of shade avoidance in leaf traits and the degree to which these leaf traits correlate with environmental factors. We find that leaf size is correlated with measures of foliar shade across the wild tomato species sampled and that leaf size and serration correlate in a species-dependent fashion with temperature and precipitation. We use far-red induced changes in leaf length as a proxy measure of the shade avoidance response, and find that shade avoidance in leaves negatively correlates with the level of foliar shade recorded at the point of origin of an accession. The direction and magnitude of these correlations varies across the leaf series, suggesting that heterochronic and/or ontogenic programs are a mechanism by which selective pressures can alter leaf size and form. This study highlights the value of wild tomato accessions for studies of both morphological and light-regulated development of compound leaves, and promises to be useful in the future identification of genes regulating potentially

  12. Effects of shading on Vallisneria natans (Lour.) H. Hara growth

    DEFF Research Database (Denmark)

    Fox, Anthony David; Meng, F; Shen, X

    2013-01-01

    Effects of surface shading were measured on above- and below-ground biomass and fruit production of Vallisneria natans (Lour.) H. Hara plants grown from seed in replicated microcosm experiments, based on a control (no shading) and four treatments (25%, 50%, 75% and 90% shading). Above- and below......, but dry weight fruit production was significantly reduced at 90% shading. We conclude that above 50% surface shading, V. natans plants suffer reductions in accumulated biomass and investment in sexual reproduction. We contend that recent expansions in the extent of the native floating water chestnut Trapa...

  13. Does greater specific leaf area plasticity help plants to maintain a high performance when shaded?

    Science.gov (United States)

    Liu, Yanjie; Dawson, Wayne; Prati, Daniel; Haeuser, Emily; Feng, Yanhao; van Kleunen, Mark

    2016-12-01

    It is frequently assumed that phenotypic plasticity can be very advantageous for plants, because it may increase environmental tolerance (fitness homeostasis). This should, however, only hold for plastic responses that are adaptive, i.e. increase fitness. Numerous studies have shown shade-induced increases in specific leaf area (SLA), and there is wide consensus that this plastic response optimizes light capture and thus has to be adaptive. However, it has rarely been tested whether this is really the case. In order to identify whether SLA plasticity does contribute to the maintenance of high biomass of plant species under shaded conditions, a meta-analytical approach was employed. The data set included 280 species and 467 individual studies from 32 publications and two unpublished experiments. Plants increased their SLA by 55·4 % on average when shaded, while they decreased their biomass by 59·9 %. Species with a high SLA under high-light control conditions showed a significantly greater ability to maintain biomass production under shade overall. However, in contrast to the expectation of a positive relationship between SLA plasticity and maintenance of plant biomass, the results indicated that species with greater SLA plasticity were less able to maintain biomass under shade. Although a high SLA per se contributes to biomass homeostasis, there was no evidence that plasticity in SLA contributes to this. Therefore, it is argued that some of the plastic changes that are frequently thought to be adaptive might simply reflect passive responses to the environment, or result as by-products of adaptive plastic responses in other traits. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Variation in color between intended matched shade and fabricated shade of dental porcelain.

    Science.gov (United States)

    Wee, Alvin G; Monaghan, Peter; Johnston, William M

    2002-06-01

    The total quantifiable color difference between shade matching and shade duplication has not been investigated formally. The purpose of this in vitro study was to evaluate and compare the color difference of the total color replication process and the direction of the individual color parameters for 3 dental porcelain shade-matching systems. The shade of 11 porcelain master disks was determined visually and instrumentally using 3 porcelain shade-matching systems: (1) Vita Lumin/Vita VMK 68, (2) Vitapan 3D-Master/Vita Omega 900, and (3) Shofu ShadeEye-EX/Vintage Halo. Corresponding porcelain disks made of 4.5 mm opaque and 1 mm dentin porcelain were fabricated with each of the porcelain systems. The colors of the master disks and fabricated disks (CIE L* a* b* coordinates) were measured with a spectroradiometer with a 45 degrees /0 degrees configuration. Repeated-measures analysis of variance was used to evaluate within-group differences among the porcelain systems for the total color difference (Delta E) and direction of the color parameters (Delta L, Delta a, and Delta b). The Ryan-Einot-Gabriel-Welsch multiple range test was used for post-hoc analysis (alpha=.05). The largest mean Delta E was recorded for the Vitapan 3D-Master system, which was significantly different from the other systems (P=.0024). A significant difference was found between the interaction of the different systems and the direction of color (P=.0024). The amount of change within each color parameter was dependent on the porcelain system, as well as the amount of change among the color parameters. Within the limitations of this study, the results suggest that reliable delivery of a properly matched restoration to existing porcelain restorations cannot be ensured regardless of the shade assessment method used (visual or computer-generated).

  15. Comparing L*a*b* color coordinates for natural teeth shades and corresponding shade tabs using a spectrophotometer.

    Science.gov (United States)

    Hassel, Alexander J; Doz, Priv; Nitschke, Ina; Rammelsberg, Peter

    2009-01-01

    It was investigated whether L*a*b* values for teeth as well as shade tabs for one 3D-Master shade were similar to one another. Teeth were measured using Vita Easyshade and L*a*b* values and the closest 3D shade was then recorded. The shade-guide tabs were also measured using the same device. 3D-Master shades yielded different L*a*b* values for the teeth than for the tabs. L* and a* values, especially, were systematically different. Therefore, Easyshade L*a*b* values for teeth and tabs could not be directly compared.

  16. Effect of shading from jointing to maturity on high molecular weight glutenin subunit accumulation and glutenin macropolymer concentration in grain of winter wheat

    DEFF Research Database (Denmark)

    Li, X.; Cai, J.; Li, H.

    2012-01-01

    the accumulation and concentration of HMW-GS in the grains. Consequently, S1 reduced falling number and SDS-sedimentation volume, while shortened dough development time (DDT) and dough stability time (DST). In contrast, S2 and S3 increased falling number, wet-gluten concentration and SDS-sedimentation volume......Accumulations of high molecular weight glutenin subunits (HMW-GS) and glutenin macropolymer (GMP) in wheat grains are important indicators of grain quality. Two wheat cultivars, Yangmai 158 (shading tolerant) and Yangmai 11 (shading intolerant) which contains the same subunit pairs of 7 + 8 and 2...... + 12, were used to evaluate the impacts of shading on HMW-GS accumulation and GMP concentration in the grain. Three shading levels were implemented from jointing to maturity, i.e. S1, S2 and S3, in which the plants received 8 %, 15 % and 23 % less radiation of the control (S0), respectively...

  17. Comparison of accuracies of an intraoral spectrophotometer and conventional visual method for shade matching using two shade guide systems.

    Science.gov (United States)

    Parameswaran, Vidhya; Anilkumar, S; Lylajam, S; Rajesh, C; Narayan, Vivek

    2016-01-01

    This in vitro study compared the shade matching abilities of an intraoral spectrophotometer and the conventional visual method using two shade guides. The results of previous investigations between color perceived by human observers and color assessed by instruments have been inconclusive. The objectives were to determine accuracies and interrater agreement of both methods and effectiveness of two shade guides with either method. In the visual method, 10 examiners with normal color vision matched target control shade tabs taken from the two shade guides (VITAPAN Classical™ and VITAPAN 3D Master™) with other full sets of the respective shade guides. Each tab was matched 3 times to determine repeatability of visual examiners. The spectrophotometric shade matching was performed by two independent examiners using an intraoral spectrophotometer (VITA Easyshade™) with five repetitions for each tab. Results revealed that visual method had greater accuracy than the spectrophotometer. The spectrophotometer; however, exhibited significantly better interrater agreement as compared to the visual method. While VITAPAN Classical shade guide was more accurate with the spectrophotometer, VITAPAN 3D Master shade guide proved better with visual method. This in vitro study clearly delineates the advantages and limitations of both methods. There were significant differences between the methods with the visual method producing more accurate results than the spectrophotometric method. The spectrophotometer showed far better interrater agreement scores irrespective of the shade guide used. Even though visual shade matching is subjective, it is not inferior and should not be underrated. Judicious combination of both techniques is imperative to attain a successful and esthetic outcome.

  18. Combined surface and volumetric occlusion shading

    KAUST Repository

    Schott, Matthias O.

    2012-02-01

    In this paper, a method for interactive direct volume rendering is proposed that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The proposed algorithm extends the recently proposed Directional Occlusion Shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. © 2012 IEEE.

  19. Shading, a view from the inside.

    Science.gov (United States)

    Koenderink, Jan J; van Doorn, Andrea; Pont, Sylvia

    2012-01-01

    Shape from shading arose from artistic practice, and later experimental psychology, but its formal structure has only been established recently by computer vision. Some of its algorithms have led to useful applications. Psychology has reversely borrowed these formalisms in attempts to come to grips with shading as a depth cue. Results have been less than spectacular. The reason might well be that these formalisms are all based on Euclidean geometry and physics (radiometry), which, are the right tools in third person accounts, but have little relevance to first person accounts, and thus are biologically (and consequently psychologically) of minor interest. We propose a formal theory of the shading cue in the first person account, 'a view from the inside'. Such a perspective is also required for autonomous robots in AI. This formalism cannot be based on Euclidean geometry, nor on radiometry, but on the structure of pictorial space, and the structure of brightness space. The formalism, though different in kind, has a simple relation to the computer vision accounts. It has great robustness, is free from calibration issues, and allows purely local shape inferences. It is especially suited to biological (and thus AI) implementation. We consider a number of predictions and confront them with available empirical evidence.

  20. An evaluation of shade differences between natural anterior teeth in different age groups and gender using commercially available shade guides.

    Science.gov (United States)

    Rodrigues, Shobha; Shetty, S Ramanand; Prithviraj, D R

    2012-12-01

    Shade selection with the help of shade guides and color matching the restorations to the natural dentition continues to be one of the most perplexing and frustrating problems in fixed prosthodontics. The purpose of the study was to evaluate the shade differences of the natural anterior teeth in different age groups and gender, within the cross sectional Bangalore, Karnataka population, using commercially available shade guides. The shade of a cross section of the population comprising of 400 subjects of both the sexes (800 incisors; 400 maxillary central incisors; 400 mandibular central incisors) visiting the outpatient Department of Government Dental College was selected randomly and evaluated visually by a single observer using three commonly used shade guides i.e. Vita Lumin, Chromascop and the Vita 3D Master. The incidence of the most common shades in the different age groups and gender using these shade guides was obtained and this data was subjected to the χ(2) test (p age group is A2/2R1.5/140 and A1/1M2/120 for the males and females using Vita Lumin, Vita 3D Master and Chromascop shade guides respectively. In the advanced age group the most common shade for the maxillary and mandibular incisors is A2/2R2.5/140 using the same order of shade guides. However the results showed no statistical significance in shade variation in males and females in different age groups using different shade guides. Although the incidence of males with darker teeth as compared to females was higher; the study showed no statistical significant correlation between shade differences in both the sexes. It is also observed that there is a significant darkening of teeth as the age advances.

  1. Water requirements and crop coefficients of tropical forest seedlings in different shading conditions

    Directory of Open Access Journals (Sweden)

    Emanoeli B. Monteiro

    Full Text Available ABSTRACT The objective was to determine the crop evapotranspiration (ETc and crop coefficients (Kc of tropical forest seedlings over a 135-day cycle, in the climatic conditions of the Cerrado-Amazon transitional region (11º 51’ 08 “S; 55º 30’ 56” W; altitude of 371 m. Five native species (Tabebuia impetiginosa, Tabebuia roseoalba, Handroanthus chrysotrichus, Parkia pendula and Parkia platycephala and one exotic species (Adenanthera pavonina were evaluated in seven shading conditions: 35, 50 and 80% black nets (Polyolefin; green Frontinet®, red ChromatiNet® and blue ChromatiNet® of 50% shading; and full sun. Reference evapotranspiration (ETo was obtained by the Penman-Monteith FAO-56 method and the crop evapotranspiration of the seedlings (ETc was given by daily weighing. The Kc values were obtained by dividing ETo by ETc. At 135 DAT, destructive analysis was performed to determine the leaf area. In full sun conditions, ETc varied from 3.9 (P. pendula to 5.0 mm d-1 (T. roseoalba. The increase in the shading percentage promotes reduction in leaf area, ETc and Kc. Colored nets with 50% shading generate similar water demands.

  2. Jussara palm seed germination under different shade levels Germinação de sementes de palmiteiro jussara sob diferentes níveis de sombreamento

    Directory of Open Access Journals (Sweden)

    Armando R Tavares

    2008-12-01

    Full Text Available Jussara palm (Euterpe edulis is a native plant of the Atlantic rainy forest, with large economic interest. The species is shade-tolerant and currently it is restricted to certain areas of difficult access. The most effective way to reintroduce it into the environment or increase the population density for conservation and commercial exploitation is promoting seed propagation. Considering that the jussara palm is an ombrophylous species, this experiment aimed to simulate forest conditions, with different shade levels, to analyze its influence on seed germination. After processing the seeds (depulping, 500 seeds were sown in containers (20 x 30 x 8 cm filled with forest ground and grown in five shade levels (0, 20, 40,60, and 80%, simulated using black shadenet. The experimental design was blocks at random, with four 25-seed replications. We evaluated the percentage of seed germination and the Emergence Speed Index (ESI. Seed germination started 103 days after sowing. Although the percentage of germinated seeds in the different treatments varied between 53 (0% shade and 72% (60% shade, there was no significant shade influence over percentage of seed germination and ESI.O palmiteiro jussara (Euterpe edulis, planta nativa da Mata Atlântica, apresenta grande importância econômica. Atualmente, sua ocorrência é restrita a algumas áreas de difícil acesso. A forma mais eficaz de reintroduzi-lo no ambiente ou de adensar suas populações com fins de conservação e exploração comercial é através das sementes. Sendo o palmiteiro uma espécie esciófila, este experimento visou simular condições de mata com diferentes níveis de sombreamento e analisar sua influência na germinação das sementes. Após o beneficiamento (despolpamento, 500 sementes foram postas para germinar em terra vegetal contida em caixas (20 x 30 x 8 cm e distribuídas em cinco níveis de sombreamento (0, 20, 40, 60 e 80% de sombra, simulado com sombrite preto. O

  3. Reliability of conventional shade guides in teeth color determination

    OpenAIRE

    Todorović Ana; Todorović Aleksandar; Špadijer-Gostović Aleksandra; Lazić Vojkan; Miličić Biljana; Đurišić Slobodan

    2013-01-01

    Background/Aim. Color matching in prosthodontic therapy is a very important task because it influences the esthetic value of dental restorations. Visual shade matching represents the most frequently applied method in clinical practice. Instrumental measurements provide objective and quantified data in color assessment of natural teeth and restorations. In instrumental shade analysis, the goal is to achieve the smallest ΔE value possible, indicating the most accurate shade match. The aim...

  4. Effects of shading on Vallisneria natans (Lour. H. Hara growth

    Directory of Open Access Journals (Sweden)

    Fox A.D.

    2013-08-01

    Full Text Available Effects of surface shading were measured on above- and below-ground biomass and fruit production of Vallisneria natans (Lour. H. Hara plants grown from seed in replicated microcosm experiments, based on a control (no shading and four treatments (25%, 50%, 75% and 90% shading. Above- and below-ground biomass was significantly reduced at treatments above 50% shading and first pistillate and staminate florescence dates were significantly delayed above 75% and 50% shading, respectively. Ratios of mature to unripe fruits produced (both in number or dry weight did not differ between shading treatments, but dry weight fruit production was significantly reduced at 90% shading. We conclude that above 50% surface shading, V. natans plants suffer reductions in accumulated biomass and investment in sexual reproduction. We contend that recent expansions in the extent of the native floating water chestnut Trapa spp. at seasonally inundated wetlands in the Yangtze River floodplain could, by shading, have contributed to the reduction in annual biomass and seed production of V. natans, contributing to declines in distribution and abundance.

  5. Sinai Peninsula, Shaded Relief and Colored Height

    Science.gov (United States)

    2004-01-01

    The Sinai Peninsula, located between Africa and Asia, is a result of those two continents pulling apart from each other. Earth's crust is cracking, stretching, and lowering along the two northern branches of the Red Sea, namely the Gulf of Suez, seen here on the west (left), and the Gulf of Aqaba, seen to the east (right). This color-coded shaded relief image shows the triangular nature of the peninsula, with the coast of the Mediterranean Sea forming the northern side of the triangle. The Suez Canal can be seen as the narrow vertical blue line in the upper left connecting the Red Sea to the Mediterranean. The peninsula is divided into three distinct parts; the northern region consisting chiefly of sandstone, plains and hills, the central area dominated by the Tih Plateau, and the mountainous southern region where towering peaks abound. Much of the Sinai is deeply dissected by river valleys, or wadis, that eroded during an earlier geologic period and break the surface of the plateau into a series of detached massifs with a few scattered oases. Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction, so that northwest slopes appear bright and southeast slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations. Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed

  6. OpenGL 4 shading language cookbook

    CERN Document Server

    Wolff, David

    2013-01-01

    OpenGL Shading Language 4 Cookbook is a hands-on guide that gets straight to the point - actually creating graphics, instead of just theoretical learning. Each recipe is specifically tailored to satisfy your appetite for producing real-time 3-D graphics using the latest GLSL specification.This book is for OpenGL programmers looking to use the modern features of GLSL 4 to create real-time, three-dimensional graphics. Familiarity with OpenGL programming, along with the typical 3D coordinate systems, projections, and transformations is assumed. It can also be useful for experienced GLSL programme

  7. Fifty shades of exploitation: Fan labor and Fifty Shades of Grey

    Directory of Open Access Journals (Sweden)

    Bethan Jones

    2014-03-01

    Full Text Available This exploration of the debates that have taken place in fandom over the ethics of pulling fan fiction and publishing it as original work draws on the notion of the fannish gift economy, which postulates that gifts such as fan fiction and fan art have value in the fannish community because they are designed to create and cement its social structure. Tension exists between fans who subscribe to the notion of a fannish gift economy and those who exploit fandom by using it to sell their pulled-to-publish works. An examination of E. L. James's 2012 Fifty Shades trilogy (comprising the books Fifty Shades of Grey, Fifty Shades Darker, and Fifty Shades Freed, which began as Twilight fan fiction, in addition to Twilight fan art sold through sites such as Redbubble and Etsy, demonstrates a tension between the two modes of fan expression: sale of artworks appears to be an acceptable practice in fandom, but the commercial sale of fan fic, even when marketed as original fiction, is widely contested.

  8. [Effects of shade and competition of Chenopodium album on photosynthesis, fluorescence and growth characteristics of Flaveria bidentis].

    Science.gov (United States)

    Yang, Qing; Li, Jing-Shi; Guo, Ai-Ying; Qi, Yan-Ling; Li, Yan-Sheng; Zhang, Feng-Juan

    2014-09-01

    It is necessary to elucidate its growth mechanism in order to prevent and control the further spread of Flaveria bidentis, an invasive plant in China. The effects of shading (shading rate of 0, 50% and 80%, respectively) and planting pattern (single cropping of F. bidentis, single cropping of Chenopodium album and their intercropping) on germination rate, fluorescence characteristics and growth characteristics of the two plants were investigated. The results showed that moderate shading contributed to emergence rate, but emergence rate of F. bidentis was not uniform, which was one of important factors as a stronger invader. With the increasing light intensity, net photosynthetic rate (Pn), photochemical quenching (qP), electron transport rate of PS II (ETR), quantum yield of PS II (Y), non-photochemical quenching (qN), water use efficiency (WUE), shoot bio-mass rate (SMR), crown width (CW) and dry biomass (DM) increased, specific leaf area (SLA) decreased, LMR of F. bidentis significantly increased, LMR of C. album changed insignificantly, and the increment of DM of F. bidentis was higher than that of C. album. In 80% shade treatment, Pn and DM of F. bidentis were lower than those of C. album. In natural light treatment, Pn, qN, WUE and relative competitive index (RCI) were the highest, CW and DM of intercropped F. bidentis and Pn, Y of C. album were significantly lower than that of the respective single treatment. F. bidentis had higher light saturation point (LSP) and light compensation point (LCP). In conclusion, the shade-tolerant ability of F. bidentis was weaker than that of C. album, but it was reversed in natural light treatment. The two plants adapted to the weak light in 80% shade treatment by increasing SLA and decreasing LMR. F. bidentis improved competition under natural light by increasing SMR and decreasing CW.

  9. Differential effect of whole-ear shading after heading on the physiology, biochemistry and yield index of stay-green and non-stay-green wheat genotypes.

    Science.gov (United States)

    Li, Qing; Zhong, Shengfu; Sun, Sifan; Fatima, Syeda Akash; Zhang, Min; Chen, Wanquan; Huang, Qianglan; Tang, Shengwen; Luo, Peigao

    2017-01-01

    Two winter wheat cultivars (the functional stay-green CN12 and non-stay-green CN19) were used to investigate the effects of ear-shading on grain yield and to elucidate the differential mechanisms of different cultivars. The photosynthetic parameters, chlorophyll fluorescence, antioxidant enzyme activities, and chlorophyll contents were measured 0, 15 and 30 days after heading (DAH) under both shaded and non-shaded conditions. The final grain-yield index was also measured. Shading had a smaller effect on the net photosynthetic rate (Pn), intercellular CO2 concentration (Ci), stomatal conductance (Gs), maximal photochemical efficiency of PSII (Fv/Fm) and coefficient of non-photochemical fluorescence quenching (qN) but a greater effect on both superoxide dismutase (SOD) and catalase (CAT) activities in CN12 than it did in CN19. Shading slightly altered the timeframe of leaf senescence in CN12 and may have accelerated leaf senescence in CN19. Moreover, shading had only a small effect on the weight of grains per spike (WGS) in CN12 compared with CN19, mainly resulting from the number of grains per spike (NGS) rather than the 1000-grain weight (SGW). In conclusion, the flag leaves of functional stay-green wheat could serve as potential "buffers" and/or "compensators" for ear photosynthesis, which is actively regulated by the antioxidant enzyme system and prevents yield loss. Thus, a functional stay-green genotype could be more tolerant to environmental stress than a non-stay-green genotype.

  10. [Application and comparison of two shade guide training systems].

    Science.gov (United States)

    Liu, Feng; Xu, Tong-kai; Xu, Ming-ming; Feng, Hai-lan; Song, Guang-ying

    2009-11-01

    To evaluate the effect of shade guide training box and shade guide training software on shade matching ability of observers when used separately. To find out the difference between two training plans when the two training methods were used in combination, and to provide information on shade matching training system. Sixty-two postgraduate dental students who specialized in prosthodontics with 1 to 5 year clinical experience were enrolled in this study. At base line, each participant were asked to match 7 standard shade tabs which have been randomly chosen from Vita 3D-Master shade guide and 7 intermediate shade tabs from Vita bleached guide 3D-Master. Then the subjects were allocated to 2 groups [Toothguide Training Box (TTB) group and Toothguide Training (TT) group] according to the baseline data. Participants in group TTB received training session once a week for 3 weeks, while those in group TT received TT training session once a week for 3 weeks. All participants took a middle term shade-matching test. Then the two groups exchange the training methods and repeat the whole process, a final test was given to each participant. The elapsed time and number of accurate shade matching were recorded for each training session. Wilcoxon signed ranks test and ANOVA were used in data analysis. There were no significant differences in the number of accurate shade matching (standard shade tab and the sum) between group TTB (4.4 +/- 1.3 and 5.3 +/- 1.6) and TT (4.0 +/- 1.4 and 4.9 +/- 1.5) in the middle term test with higher value found in group TTB. In the final test, the number of accurate shade matching (standard shade tab and the sum) in group TT (4.9 +/- 0.8 and 6.4 +/- 0.8) was higher than that in group TTB (4.7 +/- 1.1 and 5.8 +/- 0.9), but significant difference was found only when the sum number of accurate shade matching was compared between the two groups (P < 0.05). There was no significant difference between data from middle term test and from final test in group

  11. Influence of Gender on Visual Shade Matching in Dentistry.

    Science.gov (United States)

    Pecho, Oscar E; Ghinea, Razvan; Perez, Maria M; Della Bona, Alvaro

    2017-04-01

    Accuracy on visual shade matching (VSM) is one of the most difficult procedures in esthetic dentistry. Some variables can influence on this process and gender is one of the most controversial. This observational study evaluated the influence of gender on accuracy of VSM. One-hundred observers (65 females and 35 males) shade matched four human upper central incisors (UCI) to shade tabs from Vita Classical (VC) shade guide. In addition, the spectral reflectance values from the four UCI and from the 16 VC shade tabs were measured using a spectroradiometer (SP). Measurements were performed over a gray background, inside a viewing booth and under D65 illuminant (diffuse/0º geometry). CIELAB coordinates (L*, a*, and b*) were calculated according to CIE D65 illuminant and CIE 2º Standard Observer. Instrumental shade matching for each UCI, based on minimum color difference, was performed using two color difference metrics (CIELAB and CIEDE2000(2:1:1)). Data was analyzed using descriptive statistics and McNemar test (α = 0.05). Irrespective of the color difference metric, the most prevalent shade performed by females showed greater success (50% for CIELAB and 100% for CIEDE2000(2:1:1)) than males (25% for CIELAB and 50% for CIEDE2000(2:1:1)). However, such difference on gender was statistically significant only when using CIEDE2000(2:1:1) color difference metric (p ≤ 0.05). The most prevalent shade option resultant from VSM performed by females using VC shade guide perfectly agreed (100% success rate) with measurements from SP and CIEDE2000(2:1:1) color difference metric. The ability to understand and distinguish color differences in VSM is critical in clinical dentistry. Variation in shade perception due to observer gender can be minimized using additional observers and/or improving shade matching ability. (J Esthet Restor Dent 29:E15-E23, 2017). © 2017 Wiley Periodicals, Inc.

  12. Frequency and microenvironmental pattern of selection on plastic shade-avoidance traits in a natural population of Impatiens capensis.

    Science.gov (United States)

    Huber, Heidrun; Kane, Nolan C; Heschel, M Shane; von Wettberg, Eric J; Banta, Joshua; Leuck, Anne-Marie; Schmitt, Johanna

    2004-04-01

    The frequency and predictability of different selective environments are important parameters in models for the evolution of plasticity but have rarely been measured empirically in natural populations. We used an experimental phytometer approach to examine the frequency, predictability, and environmental determinants of heterogeneous selection on phytochrome-mediated shade-avoidance responses in a natural population of the annual plant Impatiens capensis. The strength and direction of selection on shade-avoidance traits varied substantially on a fine spatial scale. The shade-avoidance phenotype had high relative fecundity in some microsites but was disadvantageous in other microsites. Local seedling density proved to be a surprisingly poor predictor of microenvironmental variation in the strength and direction of selection on stem elongation in this study population. At least some of this unpredictability resulted from microenvironmental variation in water availability; the shade-avoidance phenotype was more costly in dry microsites. Thus, environmental heterogeneity in resource availability can affect the relative costs and benefits of expressing shade-avoidance traits independent of local seedling density, the inductive environmental cue. Theory predicts that these conditions may promote local genetic differentiation in reaction norms in structured populations, as observed in I. capensis.

  13. Shade tree selection and management practices by farmers in ...

    African Journals Online (AJOL)

    There is a traditional practice of forest management in coffee producing communities in Ethiopian moist Afromontane forests to increase coffee production. The practice involves removal of big canopy trees with excessive shade and selectively retaining specific tree species as preferred shade trees. This study was initiated ...

  14. Socioeconomic benefits of shade trees in coffee production systems ...

    African Journals Online (AJOL)

    Coffea Arabica is extensively cultivated by households under a variety of shade trees in southwestern Ethiopia. The main purpose of this study was to assess the overall farmers' perception on the benefits of shade trees in coffee production systems in southwestern part of Ethiopia. Semistructured questionnaires were ...

  15. Growth and morphogenesis of sun and shade plants

    NARCIS (Netherlands)

    Corre, W.J.

    1984-01-01

    A number of species of sun and shade plants in the vegetative phase were grown in different light intensities, different light qualities (r/fr ratio) and different combinations of light intensity and nutrient supply. Sun and shade species were also grown at various plant densities and in

  16. Safety Analysis of Solar Module under Partial Shading

    Directory of Open Access Journals (Sweden)

    Wei He

    2015-01-01

    Full Text Available Hot spot often occurs in a module when the qualities of solar cells mismatch and bypass diodes are proved to be an efficient alternative to reduce the effect of hot spot. However, these principles choosing a diode are based on the parameters of bypass diodes and PV cells without consideration of the maximum heating power of the shaded cell, which may cause serious consequences. On this basis, this paper presents a new approach to investigate partially shaded cells in different numbers of PV cells and different shading scenarios, including inhomogeneous illumination among solar cells and incomplete shading in one cell, which innovatively combines the same cells or divides one affected cell into many small single cells and then combines the same ones, and analyzes the shaded cell. The results indicate that the maximum power dissipation of the shaded cell occurs at short-circuit conditions. With the number of solar cells increasing, the shaded cell transfers from generating power to dissipating power and there is a maximum point of power dissipation in different shading situations that may lead to severe hot spot. Adding up the heat converted from solar energy, the heating power can be higher. In this case, some improvements about bypass diodes are proposed to reduce hot spot.

  17. Data analysis for effective monitoring of partially shaded photovoltaic systems

    NARCIS (Netherlands)

    Tsafarakis, O.|info:eu-repo/dai/nl/412471329; Sinapis, K.|info:eu-repo/dai/nl/411291572; van Sark, W.G.J.H.M.|info:eu-repo/dai/nl/074628526

    2017-01-01

    The purpose of this study is the development of an algorithmic tool to automate the process of analyzing monitoring data of partially shaded PV systems. The approach is to compare long-term and high resolution yield data of a partially shaded Photovoltaic (PV) system (investigated PV) with the yield

  18. Solar shading system based on daylight directing glass lamellas

    DEFF Research Database (Denmark)

    Laustsen, Jacob B.; Santos, Ines D. P.; Svendsen, Svend

    2008-01-01

    The overheating problems in office buildings must be solved with efficient solar shadings in order to reduce the energy demand for cooling and ventilation. At the same time the solar shading should not reduce the daylight level in the building on overcast days because it would result in a lower...

  19. Reliability of conventional shade guides in teeth color determination

    Directory of Open Access Journals (Sweden)

    Todorović Ana

    2013-01-01

    Full Text Available Background/Aim. Color matching in prosthodontic therapy is a very important task because it influences the esthetic value of dental restorations. Visual shade matching represents the most frequently applied method in clinical practice. Instrumental measurements provide objective and quantified data in color assessment of natural teeth and restorations. In instrumental shade analysis, the goal is to achieve the smallest ΔE value possible, indicating the most accurate shade match. The aim of this study was to evaluate the reliability of commercially available ceramic shade guides. Methods. VITA Easyshade spectrophotometer (VITA, Germany was used for instrumental color determination. Utilizing this device, color samples of ten VITA Classical and ten VITA 3D - Master shade guides were analyzed. Each color sample from all shade guides was measured three times and the basic parameters of color quality were examined: ΔL, ΔC, ΔH, ΔE, ΔElc. Based on these parameters spectrophotometer marks the shade matching as good, fair or adjust. Results. After performing 1,248 measurements of ceramic color samples, frequency of evaluations adjust, fair and good were statistically significantly different between VITA Classical and VITA 3D Master shade guides (p = 0.002. There were 27.1% cases scored as adjust, 66.3% as fair and 6.7% as good. In VITA 3D - Master shade guides 30.9% cases were evaluated as adjust, 66.4% as fair and 2.7% cases as good. Conclusion. Color samples from different shade guides, produced by the same manufacturer, show variability in basic color parameters, which once again proves the lack of precision and nonuniformity of the conventional method.

  20. Repeatability and reliability of human eye in visual shade selection.

    Science.gov (United States)

    Özat, P B; Tuncel, İ; Eroğlu, E

    2013-12-01

    Deficiencies in the human visual percep-tion system have challenged the efficiency of the visual shade-matching protocol. The aim of this study was to evaluate the repeatability and reliability of human eye in visual shade selection. Fifty-four volunteering dentists were asked to match the shade of an upper right central incisor tooth of a single subject. The Vita 3D-Master shade guide was used for the protocol. Before each shade-matching procedure, the definitive codes of the shade tabs were hidden by an opaque strip and the shade tabs were placed into the guide randomly. The procedure was repeated 1 month later to ensure that visual memory did not affect the results. The L*, a* and b* values of the shade tabs were measured with a dental spectrophotometer (Vita Easyshade) to produce quantitative values to evaluate the protocol. The paired samples t-test and Pearson correlation test were used to compare the 1st and 2nd selections. The Yates-corrected chi-square test was use to compare qualitative values. Statistical significance was accepted at P < 0·05. Comparing baseline and 1st month records, statistical significance (P < 0·001) was found among qualitative data regarding repeatability on a yes/no (1/0) basis, revealing a very low percentage of repeatability (11·1%). Comparing baseline and 1st month records, statistical significance was not found (P = 0·000) among the L*, a*, b* and ΔE variables. These results indicate that dentists perform insufficiently regarding repeatability in visual shade matching, but they are able to select clinically acceptable shades. © 2013 John Wiley & Sons Ltd.

  1. Shade matching assisted by digital photography and computer software.

    Science.gov (United States)

    Schropp, Lars

    2009-04-01

    To evaluate the efficacy of digital photographs and graphic computer software for color matching compared to conventional visual matching. The shade of a tab from a shade guide (Vita 3D-Master Guide) placed in a phantom head was matched to a second guide of the same type by nine observers. This was done for twelve selected shade tabs (tests). The shade-matching procedure was performed visually in a simulated clinic environment and with digital photographs, and the time spent for both procedures was recorded. An alternative arrangement of the shade tabs was used in the digital photographs. In addition, a graphic software program was used for color analysis. Hue, chroma, and lightness values of the test tab and all tabs of the second guide were derived from the digital photographs. According to the CIE L*C*h* color system, the color differences between the test tab and tabs of the second guide were calculated. The shade guide tab that deviated least from the test tab was determined to be the match. Shade matching performance by means of graphic software was compared with the two visual methods and tested by Chi-square tests (alpha= 0.05). Eight of twelve test tabs (67%) were matched correctly by the computer software method. This was significantly better (p < 0.02) than the performance of the visual shade matching methods conducted in the simulated clinic (32% correct match) and with photographs (28% correct match). No correlation between time consumption for the visual shade matching methods and frequency of correct match was observed. Shade matching assisted by digital photographs and computer software was significantly more reliable than by conventional visual methods.

  2. New shade guide for tooth whitening monitoring: visual assessment.

    Science.gov (United States)

    Paravina, Rade D

    2008-03-01

    Shade guides currently used to monitor tooth bleaching lack logical order, uniform color distribution, and light shade tabs, thus, limiting the design of bleaching studies and diminishing the validity of obtained results. The purpose of this study was to perform a visual evaluation of a new shade guide designed primarily for monitoring tooth whitening and to compare this shade guide with 2 commercial shade guides. Tab arrangement of 3 shade guides (prototype of new VITA Bleachedguide 3D-Master (BG), value scale of Vitapan Classical (VC), and color-ordered Trubyte Bioform porcelain shade guide (TB)) was evaluated. The tabs from each shade guide, one at a time, were scattered and visually reordered from the lightest to the darkest by 15 observers under controlled conditions of a viewing booth. Visual ranking was compared to manufacturer-suggested ranking. Interobserver repeatability was compared using the Mann-Whitney U test (alpha=.05). All observers responded to a questionnaire grading the 3 shade guides using a Likert scale (1, strongly disagree, to 5, strongly agree). The Kolmogorov-Smirnov z-test (alpha=.05) was used to process the results obtained in the questionnaire Visually determined BG order was found to be identical to the order given by the manufacturer. This was not the case with the 2 other products: visual and manufacturers' order were identical for 7 of 16 VC tabs and 9 of 24 TB tabs. Interobserver repeatability for BG was significantly higher (P3D-Master. The same shade guide was also superior based on the scores given in the questionnaire. These findings support the use of the new VITA Bleachedguide 3D-Master for monitoring tooth whitening.

  3. Effects of shade on physiological changes, oxidative stress, and total antioxidant power in Thai Brahman cattle

    Science.gov (United States)

    Aengwanich, Worapol; Kongbuntad, Watee; Boonsorn, Thongchai

    2011-09-01

    The purpose of this study was to assess the effects of artificial shade, tree shade, and no shade on physiological changes, oxidative stress, and total antioxidant power in Thai Brahman cattle. Twenty-one cattle were divided into three groups: cattle maintained under artificial shade, under tree shade, and without shade. On days 1, 7, 14, 21, and 28 of the experimental period, after the cattle were set in individual stalls for 2 h, physiological changes, thiobarbituric acid reactive substances (TBARS), and total antioxidant power were investigated. The results revealed that the respiratory rate, heart rate, sweat rate and the neutrophil/lymphocyte ratio of the no-shade cattle were significantly higher than those of cattle maintained under artificial shade and tree shade ( P total antioxidant power of the no-shade cattle was lower than those of cattle maintained under artificial shade and tree shade, but the total antioxidant power of cattle maintained under artificial shade and tree shade were not different ( P > 0.05). However, rectal temperature and packed cell volume of the cattle in all groups did not differ ( P > 0.05). These results showed that artificial shade and tree shade can protect cattle from sunlight compared to no shade, and that the effectiveness of tree shade for sunlight protection is at an intermediate level.

  4. Olduvai Gorge, Shaded Relief and Colored Height

    Science.gov (United States)

    2004-01-01

    Three striking and important areas of Tanzania in eastern Africa are shown in this color-coded shaded relief image from the Shuttle Radar Topography Mission. The largest circular feature in the center right is the caldera, or central crater, of the extinct volcano Ngorongoro. It is surrounded by a number of smaller volcanoes, all associated with the Great Rift Valley, a geologic fault system that extends for about 4,830 kilometers (2,995 miles) from Syria to central Mozambique. Ngorongoro's caldera is 22.5 kilometers (14 miles) across at its widest point and is 610 meters (2,000 feet) deep. Its floor is very level, holding a lake fed by streams running down the caldera wall. It is part of the Ngorongoro Conservation Area and is home to over 75,000 animals. The lakes south of the crater are Lake Eyasi and Lake Manyara, also part of the conservation area. The relatively smooth region in the upper left of the image is the Serengeti National Park, the largest in Tanzania. The park encompasses the main part of the Serengeti ecosystem, supporting the greatest remaining concentration of plains game in Africa including more than 3,000,000 large mammals. The animals roam the park freely and in the spectacular migrations, huge herds of wild animals move to other areas of the park in search of greener grazing grounds (requiring over 4,000 tons of grass each day) and water. The faint, nearly horizontal line near the center of the image is Olduvai Gorge, made famous by the discovery of remains of the earliest humans to exist. Between 1.9 and 1.2 million years ago a salt lake occupied this area, followed by the appearance of fresh water streams and small ponds. Exposed deposits show rich fossil fauna, many hominid remains and items belonging to one of the oldest stone tool technologies, called Olduwan. The time span of the objects recovered dates from 2,100,000 to 15,000 years ago. Two visualization methods were combined to produce the image: shading and color coding of

  5. Discrete Line Congruences for Shading and Lighting

    KAUST Repository

    Wang, Jun

    2013-07-01

    Two-parameter families of straight lines (line congruences) are implicitly present in graphics and geometry processing in several important ways including lighting and shape analysis. In this paper we make them accessible to optimization and geometric computing, by introducing a general discrete version of congruences based on piecewise-linear correspondences between triangle meshes. Our applications of congruences are based on the extraction of a so-called torsion-free support structure, which is a procedure analogous to remeshing a surface along its principal curvature lines. A particular application of such structures are freeform shading and lighting systems for architecture. We combine interactive design of such systems with global optimization in order to satisfy geometric constraints. In this way we explore a new area where architecture can greatly benefit from graphics.

  6. An in vitro study to evaluate the difference in shade between commercially available shade guides and glazed porcelain

    Directory of Open Access Journals (Sweden)

    P Manimaran

    2016-01-01

    Full Text Available Introduction: Smile is one of the most important interactive communication skills of a person. A smile is the key factor for an aesthetic appearance. Hence aesthetics is one of the motivating factor for the patients to seek dental care. Correction of unaesthetic appearance gives a positive effect to the self esteem of the patient. Aim: The aim of this study was to compare the difference in the shade between the commercially available shade guides namely Vita Classical And Ivoclar Chromascop and the fired porcelain samples fabricated using Vita Zahnfabrik VMK 95 and Ivoclar Classic Materials respectively. Objectives: The objective of this study was to obtain a matching brand of material that has a particular shade tab among the brands used. Conclusion: To conclude, Ivoclar material matched the chromascop shade guide better than the vita material matched the vita classic shade guide.

  7. Metameric effect between natural teeth and the shade tabs of a shade guide.

    Science.gov (United States)

    Corcodel, Nicoleta; Helling, Stephan; Rammelsberg, Peter; Hassel, Alexander J

    2010-06-01

    The objective of this study was to evaluate metameric effects, that is, the dependence of the colours of teeth and shade tabs on the illuminant used. The colours of 49 teeth of 37 participants and of the corresponding shade tabs of the 3D-Master (VITA Zahnfabrik; colour match DeltaE(ab)< 2) were measured using an intra-oral spectrophotometer (VITA Easyshade). Spectral reflectance data (from 400 to 700 nm) were recorded. Commission Internationale de l'Eclairage (CIE) L*a*b* values were calculated for D65 (reference daylight), A (incandescent light), and TL84 (store/office light) as reference illuminants. A modified metamerism index (Mod-M) and hue-angle ratios were calculated to express differences between tooth and tab colour relative to the difference observed under D65 illumination. The Mod-M for teeth and tabs was greater than unity (indicating a greater colour difference relative to D65) by 57.1% for A and by 49.3% for TL84. Hue-angle ratios of teeth and tabs using the test illuminants were different from those obtained using the standard illuminant D65. If teeth and shade tab matching is conducted using daylight illumination, the colour difference may not be the same under other lighting conditions, leading to perceptible, or even unacceptable, colour differences under these conditions.

  8. Microhardness of different resin cement shades inside the root canal.

    Science.gov (United States)

    Vignolo, Valeria; Fuentes, Maria-Victoria; Garrido, Miguel-Angel; Rodríguez, Jesús; Ceballos, Laura

    2012-09-01

    To compare microhardness along the root canal post space of two resin cements in different shades and a dual-cure resin core material. Root canals of 21 bovine incisors were prepared for post space. Translucent posts (X∘Post, Dentsply DeTrey) were luted using one the following resin luting agent: Calibra (Dentsply DeTrey) in Translucent, Medium and Opaque shades, RelyX Unicem (3M ESPE) in Translucent, A2 and A3 shades and the dual-cure resin core material Core∘X flow. All materials were applied according to manufacturers' instructions and were all photopolymerized (Bluephase LED unit, Ivoclar Vivadent, 40s). After 24 hours, roots were transversally cut into 9 slices 1 mm thick from the coronal to apical extremes, three corresponding to each root third. Then, VHNs were recorded (100gf, 30 s) on the resin luting materials along the adhesive interface in all sections. Data were analyzed by two-way ANOVA and SNK tests (α=0.05). A significant influence on microhardness of resin luting material in their respective shades (pmicrohardness values and Calibra the lowest, regardless of the shade selected. All resin luting materials tested exhibited a significantly higher microhardness in the cervical third. Microhardness of resin luting agents tested inside the canal is dependent on material brand and resin cement shade seems to be a less relevant factor. Microhardness decreased along the root canal, regardless of the shade selected.

  9. Improved grazing activity of dairy heifers in shaded tropical grasslands

    Directory of Open Access Journals (Sweden)

    Andréia Cristina Tavares de Mello

    Full Text Available ABSTRACT: Trees in the production systems can effectively reduce hot weather-induced stress in the Brazilian Midwest. High temperatures cause changes in animals daily routine, and trees into pastures can promote benefits. The aim of this research was to evaluate the behavior of dairy heifers in silvopastoral systems in the state of Mato Grosso, Brazil. A herd of 24 crossbreed heifers (3/4 and 7/8 Holstein/Zebu, 350kg average weight, was evaluated over three seasons. Piatã grass was managed under three shade levels: full-sun, moderate-shade, and intensive-shade provided by 10 to 12m high Eucalyptus trees. Behavior data were collected every 15 minutes from 8:30h to 16h. Shade availability significantly impacted heifer behavior, mainly affecting grazing frequency and time during the hottest hours. Grazing behavior was affected by shade levels during the different seasons. Heifers showed preferred grazing times. Heifers in the intensive-shade system visited shady areas during the hottest hours throughout the seasons. Heifers in the full sun-system avoided grazing during the warmer times, ceasing feeding activities. Our results from the Brazilian Midwest showed that shade availability causes breed heifers to change their daily routine.

  10. Photovoltaic Shading Testbed for Module-Level Power Electronics

    Energy Technology Data Exchange (ETDEWEB)

    Deline, C.; Meydbray, J.; Donovan, M.; Forrest, J.

    2012-05-01

    This document describes a repeatable test procedure that attempts to simulate shading situations, as would be experienced by typical residential rooftop photovoltaic (PV) systems. This type of shading test is particularly useful to evaluate the impact of different power conversion setups, including microinverters, DC power optimizers and string inverters, on overall system performance. The performance results are weighted based on annual estimates of shade to predict annual performance improvement. A trial run of the test procedure was conducted with a side by side comparison of a string inverter with a microinverter, both operating on identical 8kW solar arrays. Considering three different shade weighting conditions, the microinverter was found to increase production by 3.7% under light shading, 7.8% under moderate shading, and 12.3% under heavy shading, relative to the reference string inverter case. Detail is provided in this document to allow duplication of the test method at different test installations and for different power electronics devices.

  11. Freezing tolerance and the histology of recovering nodes in St. Augustinegrass

    Science.gov (United States)

    St. Augustinegrass [Stenataphrum secundatum (Walt.) Kuntze] is a coarse-textured turfgrass commonly utilized for its excellent shade tolerance. However, inferior cold tolerance in comparison to other warm-season grasses limits its range primarily to the southeastern U. S., The objectives of this stu...

  12. Shading-based Surface Detail Recovery under General Unknown Illumination.

    Science.gov (United States)

    Xu, Di; Duan, Qi; Zheng, Jianmin; Zhang, Juyong; Cai, Jianfei; Cham, Tat-Jen

    2017-02-17

    Reconstructing the shape of a 3D object from multi-view images under unknown, general illumination is a fundamental problem in computer vision and high quality reconstruction is usually challenging especially when fine detail is needed and the albedo of the object is non-uniform. This paper introduces vertex overall illumination vectors to model the illumination effect and presents a total variation (TV) based approach for recovering surface details using shading and multi-view stereo (MVS). Behind the approach are the two important observations: (1) the illumination over the surface of an object often appears to be piece wise smooth and (2) the recovery of surface orientation is not sufficient for reconstructing the surface, which was often overlooked previously. Thus we propose to use TV to regularize the overall illumination vectors and use visual hull to constrain partial vertices. The reconstruction is formulated as a constrained TV-minimization problem that simultaneously treats the shape and illumination vectors as unknowns. An augmented Lagrangian method is proposed to quickly solve the TV-minimization problem. As a result, our approach is robust, stable and is able to efficiently recover high quality of surface details even when starting with a coarse model obtained using MVS. These advantages are demonstrated by extensive experiments on the state-of-the-art MVS database, which includes challenging objects with varying albedo.

  13. A Custom Made Intrinsic Silicone Shade Guide for Indian Population.

    Science.gov (United States)

    Anitha, K V; Behanam, Mohammed; Ahila, S C; Jei, J Brintha

    2016-04-01

    Replication of natural skin colour in maxillofacial prosthesis has been traditionally done using trial and error method, as concrete shade guides are unavailable till date. Hence a novel custom made intrinsic silicone shade guide has been attempted for Indian population. Reconstruction of maxillofacial defects is challenging, as achieving an aesthetic result is not always easy. A concoction of a novel intrinsic silicone shade guide was contemplated for the study and its reproducibility in clinical practice was analysed. Medical grade room temperature vulcanising silicone was used for the fabrication of shade tabs. The shade guide consisted of three main groups I, II and III which were divided based upon the hues yellow, red and blue respectively. Five distinct intrinsic pigments were added in definite proportions to subdivide each group of different values from lighter to darker shades. A total number of 15 circular shade tabs comprised the guide. To validate the usage of the guide, visual assessment of colour matching was done by four investigators to investigate the consent of perfect colour correspondence. Data was statistically analysed using kappa coefficients. The kappa values were found to be 0.47 to 0.78 for yellow based group I, 0.13 to 0.65 for red based group II, and 0.07 to 0.36 for blue based group III. This revealed that the shade tabs of yellow and red based hues matched well and showed a statistically good colour matching. This intrinsic silicone shade guide can be effectively utilised for fabrication of maxillofacial prosthesis with silicone in Indian population. A transparent colour formula with definite proportioning of intrinsic pigments is provided for obtaining an aesthetic match to skin tone.

  14. Improving maximum power point tracking of partially shaded photovoltaic system by using IPSO-BELBIC

    Science.gov (United States)

    Al-Alim El-Garhy, M. Abd; Mubarak, R. I.; El-Bably, M.

    2017-08-01

    Solar photovoltaic (PV) arrays in remote applications are often related to the rapid changes in the partial shading pattern. Rapid changes of the partial shading pattern make the tracking of maximum power point (MPP) of the global peak through the local ones too difficult. An essential need to make a fast and efficient algorithm to detect the peaks values which always vary as the sun irradiance changes. This paper presents two algorithms based on the improved particle swarm optimization technique one of them with PID controller (IPSO-PID), and the other one with Brain Emotional Learning Based Intelligent Controller (IPSO-BELBIC). These techniques improve the maximum power point (MPP) tracking capabilities for photovoltaic (PV) system under partial shading circumstances. The main aim of these improved algorithms is to accelerate the velocity of IPSO to reach to (MPP) and increase its efficiency. These algorithms also improve the tracking time under complex irradiance conditions. Based on these conditions, the tracking time of these presented techniques improves to 2 msec, with an efficiency of 100%.

  15. Bond strength of different resin cement and ceramic shades bonded to dentin.

    Science.gov (United States)

    Passos, Sheila Pestana; Kimpara, Estevão Tomomitsu; Bottino, Marco Antonio; Júnior, Gildo Coelho; Rizkalla, Amin S

    2013-10-01

    To evaluate the microtensile bond strength (MTBS) of ceramic cemented to dentin varying the resin cement and ceramic shades. Two VITA VM7 ceramic shades (Base Dentine 0M1 and Base Dentine 5M3) were used. A spectrophotometer was used to determine the percentage translucency of ceramic (thickness: 2.5 mm). For the MTBS test, 80 molar dentin surfaces were etched and an adhesive was applied. Forty blocks (7.2 x 7.2 x 2.5 mm) of each ceramic shade were produced and the ceramic surface was etched (10% hydrofluoric acid) for 60 s, followed by the application of silane and resin cement (A3 yellow and transparent). The blocks were cemented to dentin using either A3 or transparent cement. Specimens were photoactivated for 20 s or 40 s, stored in distilled water (37°C/24 h), and sectioned. Eight experimental groups were obtained (n = 10). Specimens were tested for MTSB using a universal testing machine. Data were statistically analyzed using ANOVA and Tukey's post-hoc tests (α cement that was photocured for 20 s exhibited the lowest MTBS, while the transparent cement that was photocured for 40 s presented the highest MTBS. For the 2.5-mm-thick 5M3 ceramic restorations, the MTBS of ceramic cemented to dentin significantly increased. The dual-curing cement Variolink II photocured for 40 s is not recommended for cementing the Base Dentine 5M3 feldspathic ceramic to dentin.

  16. Photosynthetic rates of sun versus shade leaves of Hyptis emoryi Torr

    Energy Technology Data Exchange (ETDEWEB)

    Nobel, P.S.

    1976-08-01

    Leaves on a bush of Hyptis emoryi Torr, varied in length from less than 1 cm when development occurred in full sunlight (e.g. 40 Mjoules m/sup -2/) to over 7 cm when the total daily solar irradiance was less than 3 Mjoules m/sup -2/. The 1-cm sun leaves were 3-fold higher than the 7-cm shade leaves in chlorophyll per unit area, mesophyll thickness, and the internal to external leaf area ratio (A/sup mes//A). The higher A/sup mes//A caused a 1.2-cm leaf to have a 3-fold lower CO/sub 2/ liquid phase resistance than did a 7.1-cm leaf. Large thin shade leaves captured photosynthetically active radiation effectively (less than 7 percent passed through), but were not adapted to full sunlight. Specifically, when a 6.9-cm leaf was placed at 910 w m/sup -2/ for 30 min, its temperature exceeded that of the air by nearly 8/sup 0/C. For the common daytime air temperatures above 30/sup 0/C for this desert shrub, large shade leaves would have temperatures far in excess of that optimum for photosynthesis for H. emoryi, 29 to 32/sup 0/C.

  17. Photosynthetic Rates of Sun versus Shade Leaves of Hyptis emoryi Torr. 1

    Science.gov (United States)

    Nobel, Park S.

    1976-01-01

    Leaves on a bush of Hyptis emoryi Torr. varied in length from less than 1 cm when development occurred in full sunlight (e.g. 40 Mjoules m−2) to over 7 cm when the total daily solar irradiance was less than 3 Mjoules m−2. The 1-cm sun leaves were 3-fold higher than the 7-cm shade leaves in chlorophyll per unit area, mesophyll thickness, and the internal to external leaf area ratio (Ames/A). The higher Ames/A caused a 1.2-cm leaf to have a 3-fold lower CO2 liquid phase resistance than did a 7.1-cm leaf. Large thin shade leaves captured photosynthetically active radiation effectively (less than 7% passed through), but were not adapted to full sunlight. Specifically, when a 6.9-cm leaf was placed at 910 w m−2 for 30 min, its temperature exceeded that of the air by nearly 8 C. For the common daytime air temperatures above 30 C for this desert shrub, large shade leaves would have temperatures far in excess of that optimum for photosynthesis for H. emoryi, 29 to 32 C. PMID:16659651

  18. Interspecific competition alters natural selection on shade avoidance phenotypes in Impatiens capensis.

    Science.gov (United States)

    McGoey, Brechann V; Stinchcombe, John R

    2009-08-01

    Shade avoidance syndrome is a known adaptive response for Impatiens capensis growing in dense intraspecific competition. However, I. capensis also grow with dominant interspecific competitors in marshes. Here, we compare the I. capensis shade-avoidance phenotypes produced in the absence and presence of heterospecific competitors, as well as selection on those traits. Two treatments were established in a marsh; in one treatment all heterospecifics were removed, while in the other, all competitors remained. We compared morphological traits, light parameters, seed output and, using phenotypic selection analysis, examined directional and nonlinear selection operating in the different competitive treatments. Average phenotypes, light parameters and seed production all varied depending on competitive treatment. Phenotypic selection analyses revealed different directional, disruptive, stabilizing and correlational selection. The disparities seen in both phenotypes and selection between the treatments related to the important differences in elongation timing depending on the presence of heterospecifics, although environmental covariances between traits and fitness could also contribute. Phenotypes produced by I. capensis depend on their competitive environment, and differing selection on shade-avoidance traits between competitive environments could indirectly select for increased plasticity given gene flow between populations in different competitive contexts.

  19. Australia, Shaded Relief and Colored Height

    Science.gov (United States)

    2004-01-01

    Australia is the world's smallest, flattest, and (after Antarctica) driest continent, but at 7.7 million square kilometers (3.0 million square miles) it is also the sixth largest country. Its low average elevation (300 meters, or less than 1000 feet) is caused by its position near the center of a tectonic plate, where there are no volcanic or other geologic forces of the type that raise the topography of other continents. In fact Australia is the only continent without any current volcanic activity at all - the last eruption took place 1400 years ago at Mt. Gambier. The Australian continent is also one of the oldest land masses, with some of its erosion-exposed bedrock age dated at more than 3 billion years. More than one-fifth of the land area is desert, with more than two-thirds being classified as arid or semi-arid and unsuitable for settlement. The coldest regions are in the highlands and tablelands of Tasmania and the Australian Alps at the southeastern corner of the continent, location of Australia's highest point, Mt. Kosciusko (2228 meters, or 7310 feet.) Prominent features of Australia include the Lake Eyre basin, the darker green region visible in the center-right. At 16 meters (52 feet) below sea level this depression is one of the largest inland drainage systems in the world, covering more than 1.3 million square kilometers (500,000 square miles). The mountain range near the east coast is called the Great Dividing Range, forming a watershed between east and west flowing rivers. Erosion has created deep valleys, gorges and waterfalls in this range where rivers tumble over escarpments on their way to the sea. The crescent shaped uniform green region in the south, just left of center, is the Nullarbor Plain, a low-lying limestone plateau which is so flat that the Trans-Australian Railway runs through it in a straight line for more than 483 kilometers (300 miles). Two visualization methods were combined to produce this image: shading and color coding of

  20. Properly placed shade trees reduce summertime electricity bills in Sacramento, California

    Science.gov (United States)

    Geoffery H. Donovan; David R. Butry

    2009-01-01

    The discovery that shade trees can reduce home cooling costs is hardly surprising. Anybody who has sat under a tree on a warm summer day understands the shade benefit of trees. However, quantifying the effect a shade tree has on home energy use and carbon footprint, and identifying the optimal location for a shade tree, is less straightforward. Past studies that have...

  1. Grayscale North America Shaded Relief ? 1-Kilometer Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The grayscale North America shaded relief data were derived from the GTOPO30 elevation data. GTOPO30 is a global digital elevation model (DEM) with a horizontal grid...

  2. Evaluation of the Aurora Application Shade Measurement Accuracy

    Energy Technology Data Exchange (ETDEWEB)

    2015-12-01

    Aurora is an integrated, Web-based application that helps solar installers perform sales, engineering design, and financial analysis. One of Aurora's key features is its high-resolution remote shading analysis.

  3. Grayscale Hawaii Shaded Relief ? 200-Meter Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The grayscale Hawaii shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of Hawaii at a resolution of 200 meters. The...

  4. Dynamic Shade and Irradiance Simulation of Aquatic Landscapes and Watersheds

    Science.gov (United States)

    Penumbra is a landscape shade and irradiance simulation model that simulates how solar energy spatially and temporally interacts within dynamic ecosystems such as riparian zones, forests, and other terrain that cast topological shadows. Direct and indirect solar energy accumulate...

  5. Satellite View of Hawaii, with Shaded Relief - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Satellite View of Hawaii, with Shaded Relief map layer is a 200- meter-resolution simulated-natural-color image of Hawaii. Vegetation is generally green, with...

  6. Color Alaska Shaded Relief ? 200-Meter Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The color Alaska shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of Alaska at a resolution of 200 meters. The NED is...

  7. Color Hawaii Shaded Relief ? 200-Meter Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The color Hawaii shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of Hawaii at a resolution of 200 meters. The NED is...

  8. Satellite View of Alaska, with Shaded Relief - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Satellite View of Alaska, with Shaded Relief map layer is a 200- meter-resolution simulated-natural-color image of Alaska. Vegetation is generally green, with...

  9. The role of enamel crystallography on tooth shade.

    Science.gov (United States)

    Eimar, Hazem; Marelli, Benedetto; Nazhat, Showan N; Abi Nader, Samer; Amin, Wala M; Torres, Jesus; de Albuquerque, Rubens F; Tamimi, Faleh

    2011-12-01

    Tooth shade is influenced by a combination of extrinsic-stains that are adsorbed to the enamel surface and by its intrinsic-shade resulting from the interaction of light with tooth structures. This study was designed to investigate how the variations in enamel ultrastructure may affect tooth optical properties. One-hundred extracted teeth were collected from adult patients attending McGill-Undergraduate Dental Clinics. Shade-spectrophotometry, FTIR and XRD were used to assess tooth shade, enamel chemical composition and crystallography. The data obtained was analysed for Pearson correlation analysis and multiple linear regression analysis. The statistical significance was set at P enamel hydroxyapatite (HA) crystal size (R = -0.358; B = -0.866; P = 0.007), tooth chroma was associated with enamel HA carbonization (R = -0.419; B = -99.06; P = 0.005), and tooth lightness was associated with both enamel HA crystal size (R = -0.313; B = -1.052; P = 0.019) and the degree of HA carbonization (R = -0.265; B=-57.95; P = 0.033). Multiple linear regression analysis demonstrated that the size of enamel HA crystals and the relative content of mineral carbonate were the most important predictors for tooth shade lightness (P = 0.018) and chroma (P=0.008), respectively. In contrast, enamel organic content had no correlation with tooth shade. In the present study we have revealed that the tooth shade is regulated by the size of their HA enamel crystals. On the other hand, variation in the degree of enamel HA carbonization can also affect the tooth shade. These findings are of great relevance in dentistry since it provides better understanding of tooth aesthetics. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. The effect of various disinfectants on dental shade guides.

    Science.gov (United States)

    Huang, Peterson Y; Masri, Radi; Romberg, Elaine; Driscoll, Carl F

    2014-09-01

    Dental shade guides are used to evaluate tooth color before prosthodontic procedures and are subjected to disinfection after use. The effect of disinfection on shade guides has not been thoroughly investigated. The purpose of this study was to evaluate the effect of disinfectants on the color of shade tabs. Changes in the color (ΔE) of VITA Classical Shade Guide tabs were measured with a VITA Easyshade spectrophotometer in the CIELAB system and calculated after being subjected to Cavicide, Asepticare TB, Sporicidin, and distilled water (control) over a simulated period of 2 years. Statistical analysis was accomplished by a 2-way analysis of variance followed by the Tukey honestly significant difference (HSD) test (α=.05). A significant difference was noted in the degree of shade tab color change, depending on the type of disinfectant used (F=153.2, P<.001). No significant difference was noted in the amount of shade tab color change that occurred after disinfection among the different shade tabs used (F=0.611, P=.865), nor was a significant interaction noted between the type of disinfectant and the different shade tabs used (F=0.7, P=.919). Asepticare TB showed the least significant amount of change (ΔE=0.401), and Sporicidin (ΔE=0.889) and the control (ΔE=0.969) showed significantly more color change than Asepticare TB but less than Cavicide (ΔE=1.198). The average total CIELAB color difference for 50% human perceptibility is approximately 1 unit (under standardized laboratory conditions). In the oral cavity, however, an average change of 3.7 ΔE units could still allow teeth to be perceived as having the same color. Therefore, although the results are statistically significant, they may not be clinically important. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  11. On the Impact of Partial Shading on PV Output Power

    DEFF Research Database (Denmark)

    Sera, Dezso; Baghzouz, Yahia

    2008-01-01

    clarifies the mechanism of partial PV shading on a number of PV cells connected in series and/or parallel with and without bypass diodes. The analysis is presented in simple terms and can be useful to someone who wishes to determine the impact of some shading geometry on a PV system. The analysis...... is illustrated by measurements on a commercial 70 W panel, and a 14.4 kW PV array....

  12. Field Testing of Tomato Chilling Tolerance under Varying Light and Temperature Conditions Caracterización de la Tolerancia al Frío en Tomate Dependiente de las Condiciones de Luz y Temperatura

    Directory of Open Access Journals (Sweden)

    Rafael Elizondo

    2010-12-01

    Full Text Available Chilling tolerance is a desirable trait in commercial tomato varieties, in order to extend the growing season and geographic range. Two Nearly Isogenic Lines (NILs with introgressions in chromosome 2 and 3 of Solanum habrochaites S. Knapp & D.M. Spooner, a cold-resistant wild tomato, were evaluated in the field. Four plantings were established between 21 August and 2 October 2006 (day 232 and 274. Throughout the experiment the heat sum was interpreted using air temperature to calculate growing degree days (base 12 °C and chilling hours (below 12 °C, with the daily light integral calculated as global solar radiation. The relative post-transplant growth rate, fruit set and yield, were evaluated over two successive 10-d periods. Chilling tolerance is expressed under high radiation and low temperature conditions, which occurred during the 10-d post-transplant evaluation period beginning on day 257, when both NILs achieved a leaf area growth rate 1.7 times higher than the control plants. During the second evaluation period, 10-20 d post-transplant, both NILs grew on average, 1.4 times more than the control. There were no significant differences in earliness or fruit set. These NILs should not be used as a direct source to obtain chilling tolerant varieties, because of the low fruit set, 84% lower in LA3921 than the control, probably due to linkage drag and poor environmental adaptability in both lines.La resistencia al frío es una característica deseable en cultivares de tomate, entre otras razones para ampliar el período de cultivo y la distribución geográfica. Se evaluaron dos líneas casi isogénicas de tomate, LA3921 y LA 3925 con introgresiones de Solanum habrochaites S. Knapp & D.M. Spooner (especie resistente al frío. Las introgresiones se ubican en los cromosomas 2 y 3. Se establecieron cuatro fechas al aire libre, entre el día juliano 232 y 274 (21 de agosto al 2 de octubre. Se analizó el clima en los períodos evaluados

  13. Comparison of accuracies of an intraoral spectrophotometer and conventional visual method for shade matching using two shade guide systems

    Directory of Open Access Journals (Sweden)

    Vidhya Parameswaran

    2016-01-01

    Conclusion: This in vitro study clearly delineates the advantages and limitations of both methods. There were significant differences between the methods with the visual method producing more accurate results than the spectrophotometric method. The spectrophotometer showed far better interrater agreement scores irrespective of the shade guide used. Even though visual shade matching is subjective, it is not inferior and should not be underrated. Judicious combination of both techniques is imperative to attain a successful and esthetic outcome.

  14. Effect of substrate shades on the color of ceramic laminate veneers.

    Science.gov (United States)

    Azer, Shereen S; Rosenstiel, Stephen F; Seghi, Robert R; Johnston, William M

    2011-09-01

    Ceramic laminate veneers are generally fabricated with varying thicknesses ranging from 0.3 to 1 mm, depending on the need to mask discolored teeth or slightly correct the contour of malpositioned teeth. Clinical color reproduction poses a challenge because of color interaction with the underlying substrate, whether tooth structure or esthetic restorative material. The purpose of this in vitro investigation was to measure the effect of color change resulting from applying 2 shades of ceramic material, translucent (T1) and opaque (O2), to 2 shades of composite resin substrate material, light (A3) and dark (C4), on the overall color of ceramic laminates. Forty disks were fabricated. Twenty disks (15 × 0.5 mm) were cut from pressed ceramic, 10 disks for each shade (translucent and opaque). Additionally, 20 disks (15 × 4.0 mm) were fabricated from light-polymerized composite resin material, 10 disks for each shade (light and dark). The ceramic disks were bonded to the composite resin disks with clear resin cement. The specimen combinations were divided into 4 groups (n=5). Color measurements were done with a colorimeter (Minolta Chroma Meter CR-200b) configured with diffuse illumination/0-degree viewing geometry. Mean CIE lightness (L*), chroma (C*(ab)), and hue angle (h(ab)) values were obtained. A 2-way analysis of variance (ANOVA) was used to compare the means and standard deviations between the different color combinations (α=.05), followed by Tukey's HSD post hoc test for significant interactions. The 2-way ANOVA showed significant differences (Pceramic material shade. There was significant color change from dark to light substrate (P=.044). The mean h(ab) (SD) of dark substrate/opaque veneer was 89.62 (1.5), while the mean h(ab) of light substrate/translucent veneer was 81.23 (1.7). Within the limitations of this study, the selected color of a 0.5 mm ceramic laminate veneer was significantly affected by the change in color of the supporting substrate

  15. Influence of Color Education and Training on Shade Matching Skills.

    Science.gov (United States)

    Ristic, Ivan; Stankovic, Sasa; Paravina, Rade D

    2016-09-01

    To evaluate the influence of education and training on quality of tooth color matching. Dental students (N = 174), matched the color of eight shade tabs in a viewing booth, using VITA Linearguide 3D-Master shade guide. The experimental group had color education and training between the before and after session. The control group did not have any additional information in between two sessions. Color differences between the task tabs and selected tabs were calculated using CIE formulas. The score for the best match (smallest color difference) was 10 points, the 2nd best match 9 points, down to 1 point for the 10th best match. Means and standard deviations were calculated. Differences were analyzed using the Student t-test. Shade matching scores in the experimental group were significantly better after education and training (p < 0.001), with a mean score before and after shade matching sessions of 7.06 (1.19) and 8.43 (0.92), respectively. The percentage of students in the experimental group that selected one of three best matches increased 24.3%. The control group exhibited no significant improvement in the after session. Within the limitations of the study, education and training improved students' shade matching skills. While the vast majority of dental restorations and practically all restorations in the esthetic zone are tooth colored, the profession as a whole is far from perfect when it comes to accurate shade matching. Education and training can improve shade matching ability: enhanced esthetics of dental restorations, increased patient satisfaction, and a reduced number of color corrections are some of the notable benefits and rewards. (J Esthet Restor Dent 00:000-000, 2016) J Esthet Restor Dent 28:287-294, 2016). © 2016 Wiley Periodicals, Inc.

  16. Simplified Method for Modeling the Impact of Arbitrary Partial Shading Conditions on PV Array Performance: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    MacAlpine, Sara; Deline, Chris

    2015-09-15

    It is often difficult to model the effects of partial shading conditions on PV array performance, as shade losses are nonlinear and depend heavily on a system's particular configuration. This work describes and implements a simple method for modeling shade loss: a database of shade impact results (loss percentages), generated using a validated, detailed simulation tool and encompassing a wide variety of shading scenarios. The database is intended to predict shading losses in crystalline silicon PV arrays and is accessed using basic inputs generally available in any PV simulation tool. Performance predictions using the database are within 1-2% of measured data for several partially shaded PV systems, and within 1% of those predicted by the full, detailed simulation tool on an annual basis. The shade loss database shows potential to considerably improve performance prediction for partially shaded PV systems.

  17. Tooth shade measurements under standard and nonstandard illumination and their agreement with skin color.

    Science.gov (United States)

    Al-Dwairi, Ziad; Shaweesh, Ashraf; Kamkarfar, Sohrab; Kamkarfar, Shahrzad; Borzabadi-Farahani, Ali; Lynch, Edward

    2014-01-01

    The purpose of this study was to examine the relationship between skin color (shade) and tooth shade under standard and nonstandard illumination sources. Four hundred Jordanian participants (200 males, 200 females, 20 to 50 years of age) were studied. Skin colors were assessed and categorized using the L'Oreal and Revlon foundation shade guides (light, medium, dark). The Vita Pan Classical Shade Guide (VPCSG; Vident) and digital Vita EasyShade Intraoral Dental Spectrophotometer (VESIDS; Vident) were used to select shades in the middle thirds of maxillary central incisors; tooth shades were classified into four categories (highest, high, medium, low). Significant gender differences were observed for skin colors (P = .000) and tooth shade guide systems (P = .001 and .050 for VPCSG and VESIDS, respectively). The observed agreement was 100% and 93% for skin and tooth shade guides, respectively. The corresponding kappa statistic values were 1.00 and 0.79, respectively (substantial agreement, P < .001). The observed agreement between skin color and tooth shades (VPCSG and VESIDS) was approximately 50%. The digital tooth shade guide system can be a satisfactory substitute for classical tooth shade guides and clinical shade matching. There was only moderate agreement between skin color and tooth shade.

  18. Shading and watering as a tool to mitigate the impacts of climate change in sea turtle nests.

    Directory of Open Access Journals (Sweden)

    Jacob E Hill

    Full Text Available Increasing sand temperatures resulting from climate change may negatively impact sea turtle nests by altering sex ratios and decreasing reproductive output. We analyzed the effect of nest shading and watering on sand temperatures as climate mitigation strategies in a beach hatchery at Playa Grande, Costa Rica. We set up plots and placed thermocouples at depths of 45 cm and 75 cm. Half of the plots were shaded and half were exposed to the sun. Within these exposure treatments, we applied three watering treatments over one month, replicating local climatic conditions experienced in this area. We also examined gravimetric water content of sand by collecting sand samples the day before watering began, the day after watering was complete, and one month after completion. Shading had the largest impact on sand temperature, followed by watering and depth. All watering treatments lowered sand temperature, but the effect varied with depth. Temperatures in plots that received water returned to control levels within 10 days after watering stopped. Water content increased at both depths in the two highest water treatments, and 30 days after the end of water application remained higher than plots with low water. While the impacts of watering on sand temperature dissipate rapidly after the end of application, the impacts on water content are much more lasting. Although less effective at lowering sand temperatures than shading, watering may benefit sea turtle clutches by offsetting negative impacts of low levels of rain in particularly dry areas. Prior to implementing such strategies, the natural conditions at the location of interest (e.g. clutch depth, environmental conditions, and beach characteristics and natural hatchling sex ratios should be taken into consideration. These results provide insight into the effectiveness of nest shading and watering as climate mitigation techniques and illustrate important points of consideration in the crafting of such

  19. Accuracy of Three Shade-matching Devices in Replicating the Shade of Metal Ceramic Restorations: An in vitro Study.

    Science.gov (United States)

    Lakhanpal, Shruti; Neelima, Menon S

    2016-12-01

    In restorative dentistry, the clinician commonly encounters the challenge of replicating the color of natural teeth due to the subjectivity of perceptual evaluation. Recent advances in photography and computing have resulted in the widespread use of the digital camera for color imaging. These instruments can be used effectively for shade matching and communication to yield predictable results. The study sample consisted of 20 freshly extracted noncarious premolars. The Commission Internationale de l'Eclairage (CIE) L*a*b* values of the tooth were obtained through a spectrophotometer, digital camera, and digital camera with a polarizer. Shade selection was carried out using VITA 3D Master and calculating the Euclidian distance. The fabricated metal ceramic crowns were then evaluated to check the shade replication by comparing the CIE L*a*b* values of the crowns with the reference shade tab images. The three-way analysis of variance (ANOVA) and comparative analysis using Bonferroni test reveals that the difference in the mean L*a* values between spectrophotometer and polarization dental imaging modality (PDIM) was insignificant. The difference in the mean L*a*b* of spectrophotometer and digital camera was statistically significant. The mean ΔE for metal ceramic crowns and shade tabs was 4.2 that was greater than the clinically acceptable level (3.2). A statistically significant correlation was found to exist between the spectrophotometer and PDIM for all CIE L*, a*, and b* color coordinates. The present study was undertaken to assess the shade-matching ability of three shade-matching devices, such as spectrophotometer, digital camera, and PDIM, in the accuracy of replication of metal ceramic restorations.

  20. Adaptive comfort model for tree-shaded outdoors in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Reuy-Lung [Department of Architecture, National United University, 1 Lienda, Miaoli 360 (China); Lin, Tzu-Ping [Department of Leisure Planning, National Formosa University, 64 Wen-hua Road, Huwei, Yunlin 632 (China); Cheng, Ming-Jen; Lo, Jen-Hao [Department of Architecture, Feng Chia University, 100 Wen-hwa Road, Taichung 407 (China)

    2010-08-15

    Tree-shaded outdoors can reduce the heat effect by ameliorating the microclimate and enhancing the human thermal comfort outdoors; for this reason, they are main places for rest, recreation and social activity in Taiwan's cities. Field comfort surveys of 3839 interviewees were conducted in tree-shaded spaces throughout a year. The aims were to obtain a better understanding of human thermal comfort response outdoors and to propose an adaptive comfort model for tree-shaded spaces. A comfort zone, centering on neutral operative temperature which is an empirically derived linear function of mean monthly outdoor temperature, of 6 C for 90% acceptability and 8 C for 80% acceptability was suggested for tree-shaded spaces from surveyed data, adding that a non-linear function of the temperature difference between actual operative temperature and neutral operative temperature was established that aims to predict the percentage of heat or cold discomfort at a particular outdoor thermal condition. An application of the established adaptive comfort model on an actual tree-shaded space was demonstrated to show its practicality in long-term evaluation of a particular thermal environment. (author)

  1. Shading performance of a vertical deciduous climbing plant canopy

    Energy Technology Data Exchange (ETDEWEB)

    Ip, Kenneth; Lam, Marta; Miller, Andrew [Centre for Sustainability of the Built Environment, School of Environment and Technology, University of Brighton, Cockcroft Building, Lewes Road, Brighton BN2 4GJ, East Sussex (United Kingdom)

    2010-01-15

    Deciduous climbing plant canopies strategically integrated to building facades can act as dynamic solar shading devices responsive to the seasonal climatic changes. Maximum shading occurs in the summer when the plant is at its peak growth. The shedding of leaves in autumn and winter reduces the shading and allows beneficial solar radiation to be absorbed by the opaque surface of the building facade or penetrated through the windows to the building interior. Although climbing plants have long been used for moderating the microclimate of buildings, there are very few scientific investigations to quantify such effects. This paper reports the findings of a study with specific focus on the shading performance of a vertical deciduous climbing plant canopy. It justifies the selection of Virginia Creeper as an appropriate plant for growth in the UK climate and describes the planting, monitoring and analysis procedures adopted to determine a proposed dynamic Bioshading Coefficient Function - which is used to represent the shading performance of the climbing plant canopy over its annual growing and wilting cycle. A thermal model was developed which identified the key parameters required for establishing the Bioshading Coefficients. Two climbing plant canopies (referred to as Bioshaders) were set up in an existing building in Southeast UK and monitored for 2 years. Measured data were used to calculate a series of daily Bioshading Coefficients which were subsequently applied to establish the Bioshading Coefficient Function. The research also identified issues affecting the indoor environment as a result of the application of Bioshaders. (author)

  2. SHADE: A Shape-Memory-Activated Device Promoting Ankle Dorsiflexion

    Science.gov (United States)

    Pittaccio, S.; Viscuso, S.; Rossini, M.; Magoni, L.; Pirovano, S.; Villa, E.; Besseghini, S.; Molteni, F.

    2009-08-01

    Acute post-stroke rehabilitation protocols include passive mobilization as a means to prevent contractures. A device (SHADE) that provides repetitive passive motion to a flaccid ankle by using shape memory alloy actuators could be of great help in providing this treatment. A suitable actuator was designed as a cartridge of approximately 150 × 20 × 15 mm, containing 2.5 m of 0.25 mm diameter NiTi wire. This actuator was activated by Joule’s effect employing a 7 s current input at 0.7 A, which provided 10 N through 76 mm displacement. Cooling and reset by natural convection took 30 s. A prototype of SHADE was assembled with two thermoplastic shells hinged together at the ankle and strapped on the shin and foot. Two actuators were fixed on the upper shell while an inextensible thread connected each NiTi wire to the foot shell. The passive ankle motion (passive range of motion, PROM) generated by SHADE was evaluated optoelectronically on three flaccid patients (58 ± 5 years old); acceptability was assessed by a questionnaire presented to further three flaccid patients (44 ± 11.5 years old) who used SHADE for 5 days, 30 min a day. SHADE was well accepted by all patients, produced good PROM, and caused no pain. The results prove that suitable limb mobilization can be produced by SMA actuators.

  3. One-dimensional color order system for dental shade guides.

    Science.gov (United States)

    O'Brien, W J; Groh, C L; Boenke, K M

    1989-11-01

    The purpose of this study was to re-arrange the master Bioform shade guide into a long-range one-dimensional color system based upon color difference. Although most shade guides may show local order when arranged according to hue, long-range order has not been established. However, shade guide arrangement according to a logical color order would be an advantage to the user. The first step in determining the color order was to measure the color of the shade guide teeth. A methodology was developed for measuring the color by use of a reflectance spectrophotometer. The precision of measurement was determined to be equal to CIE L*a*b* delta E of 0.5. Spectra were obtained and converted into CIE L*a*b* and Munsell notation. The measured colors of the Bioform shades ranged from a Munsell hue of 0.9 Y to 3.5 Y; a value of 6.6 to 7.8; and a chroma of 1.9 to 4.1. The teeth were then arranged visually from light to dark. The correlation coefficient between the visual ranking and color difference was 0.95. There was an inverse correlation between visual ranking and Munsell value, with a correlation coefficient of 0.90. Therefore, the sequence according to color difference provided the better agreement with visual perception.

  4. Analysis of the U.S. forest tolerance patterns depending on current and future temperature and precipitation

    Science.gov (United States)

    Jean Lienard; John Harrison; Nikolay. Strigul

    2015-01-01

    Forested ecosystems are shaped by climate, soil and biotic interactions, resulting in constrained spatial distribution of species and biomes. Tolerance traits of species determine their fundamental ecological niche, while biotic interactions narrow tree distributions to the realized niche. In particular, shade, drought and waterlogging tolerances have been well-...

  5. Differential effect of whole-ear shading after heading on the physiology, biochemistry and yield index of stay-green and non-stay-green wheat genotypes.

    Directory of Open Access Journals (Sweden)

    Qing Li

    Full Text Available Two winter wheat cultivars (the functional stay-green CN12 and non-stay-green CN19 were used to investigate the effects of ear-shading on grain yield and to elucidate the differential mechanisms of different cultivars. The photosynthetic parameters, chlorophyll fluorescence, antioxidant enzyme activities, and chlorophyll contents were measured 0, 15 and 30 days after heading (DAH under both shaded and non-shaded conditions. The final grain-yield index was also measured. Shading had a smaller effect on the net photosynthetic rate (Pn, intercellular CO2 concentration (Ci, stomatal conductance (Gs, maximal photochemical efficiency of PSII (Fv/Fm and coefficient of non-photochemical fluorescence quenching (qN but a greater effect on both superoxide dismutase (SOD and catalase (CAT activities in CN12 than it did in CN19. Shading slightly altered the timeframe of leaf senescence in CN12 and may have accelerated leaf senescence in CN19. Moreover, shading had only a small effect on the weight of grains per spike (WGS in CN12 compared with CN19, mainly resulting from the number of grains per spike (NGS rather than the 1000-grain weight (SGW. In conclusion, the flag leaves of functional stay-green wheat could serve as potential "buffers" and/or "compensators" for ear photosynthesis, which is actively regulated by the antioxidant enzyme system and prevents yield loss. Thus, a functional stay-green genotype could be more tolerant to environmental stress than a non-stay-green genotype.

  6. Self-shading correction for oceanographic upwelling radiometers.

    Science.gov (United States)

    Leathers, Robert; Downes, Trijntje; Mobley, Cutris

    2004-10-04

    We present the derivation of an analytical model for the self-shading error of an oceanographic upwelling radiometer. The radiometer is assumed to be cylindrical and can either be a profiling instrument or include a wider cylindrical buoy for floating at the sea surface. The model treats both optically shallow and optically deep water conditions and can be applied any distance off the seafloor. We evaluate the model by comparing its results to those from Monte Carlo simulations. The analytical model performs well over a large range of environmental conditions and provides a significant improvement to previous analytical models. The model is intended for investigators who need to apply self-shading corrections to radiometer data but who do not have the ability to compute shading corrections with Monte Carlo simulations. The model also can provide guidance for instrument design and cruise planning.

  7. INITIAL DEVELOPMENT OF AÇAÍ PLANTS UNDER SHADE GRADATION

    Directory of Open Access Journals (Sweden)

    ELEANDRO CANDIDO DAPONT

    2016-01-01

    Full Text Available ABSTRACT In order to evaluate the effect of different levels of shading on açai (Euterpe oleracea Mart. plants development, an experiment was conducted at the nursery of Floresta, Rio Branco, AC. The experiment was arranged in a completely randomized design with six treatments and four replications of 25 plants, set as full sunlight and 18%, 35%, 50%, 70%, and 80% shading. The evaluation occurred 125 days after transplantation and the variables were stem diameter, root length, length of the aerial part, total length, dry matter of root, dry matter of aerial part, and total dry matter. With exception of root length, there was significant difference between treatments for all variables. The production of açai plants should be performed using 40% shading.

  8. Costly tolerance

    African Journals Online (AJOL)

    2016-07-08

    Jul 8, 2016 ... It shows how this decision is related to the broader context of early twentieth century political life in the Netherlands. (the 'Pacification of 1917'), and it concludes with some thoughts on the costliness of true tolerance. Costly tolerance. Read online: Scan this QR code with your smart phone or mobile device.

  9. Shade-lux simulation model for the evaluation of energy savings in buildings provided with external non homogeneous shading devices

    Energy Technology Data Exchange (ETDEWEB)

    Ferro, P. [CIRPS, Centro Interuniv. de Ricerca per i Paesi in Via di Sviluppo, Roma (Italy); Maccari, A. [ENEA, Ente Nazionale per l' Energia e l' Ambiente, Roma (Italy)

    2000-07-01

    During the hot season, an important amount of energy is necessary to guarantee good internal conditions in tertiary buildings, especially in those used during the daytime and provided with large glazed surfaces exposed to the sun. In order to reduce such amount of energy consumption specific shading devices are required, in particular in buildings located in the Mediterranean area where the solar radiation values are very high. The main purpose of this work is to develop a simulation model that allows to evaluate the energy performances of a building equipped with external non-homogeneous shading devices, traditional or innovative glass surfaces, and internal curtains (complex building envelope transparent systems, BETS) taking also into account the lighting load necessary to guarantee an adequate level of illuminance. In a widely diffused computer code two new routines have been added in order to evaluate the shading factor of the above-mentioned shading devices and the internal daylighting performance. Several runs of the modified program were carried out considering three different sizes of shading devices, with two values of reflectance coefficient, in horizontal position located a south facade with 33%, 50% and 65% of glass surface in three different Italian locations: Milan, Rome and Palermo. The results show that significant energy savings, up to about 40% in terms of primary energy and a diminution of up to 45% of the cooling system power, can be obtained. (au)

  10. Comparison of Shade Match Compatibility between Vitapan Classical and 3D Master Shade Guide Systems by Dental Students in Tabriz Faculty of Dentistry

    Directory of Open Access Journals (Sweden)

    Ramin Negahdari

    2016-01-01

    Full Text Available Background and Aims: Dentists perform color-match process during indirect and direct restorations. Color research has shown that shade guides do not always match the color of natural teeth. Moreover, visual evaluation of dental colors has been found to be inconsistent and unreliable. In fact, it has always been important when using different shade guides. Our purpose in this study was to compare shade selection using two shade guide systems of Vitapan Classical and 3D Master by dental students of Tabriz University of Medical Sciences. Materials and methods: In this analytical, cross-sectional descriptive study, 20 male and 20 female senior dental students with a little clinical experience in working with shade guides were selected. Each student used two shade guides (Vitapan Classical and 3D Master separately for shade matching. Shade selection was randomly repeated one week later by the same protocol. T-test was used to compare repeatability of color matching (α=0.05. Comparison of the repeatability percentage was done with t-test. Results: Comparison of repeatability percentages of shade matching irrespective of gender showed that percentage of repeatability of shade match in 3D Master system was significantly high (P=0.00. In addition comparison of repeatability means of shade match with different shade guide systems on the basis of gender showed no significant differences (P=0.68. Conclusion: In general, the repeatability percentages of shade matching in 3D Master system was high and shade matching in females with this system was not different than males.   Key words: Color vision; indirect restorations; dental students

  11. Shading Performance on Terraced House Facades in Putrajaya, Malaysia

    Directory of Open Access Journals (Sweden)

    Hassan Ahmad Sanusi

    2015-01-01

    Full Text Available This study evaluates shading performance on house facades of selected three terraced houses in Putrajaya, Malaysia as the case studies. Terraced house type is selected for the case study because it is the most popular house type built in this country to house an increase of the urban population. Its total number built in urban area increases from 27% of the total dwellings in 1980 to 40% in 1990, and to slightly more than 60 per cent in 2000. The Case Study A, B, and C are atypical style of terraced house facade designs built in Putrajaya. These postmodern designs exhibit a range of complex geometric elements blending of colonial and traditional elements with colorful styles on the house facade. In this study, the time at which the sun path perpendicular to the house facade will be used to gain the results of shading performances when the house facades have their maximum exposure to the direct sunlight. The house facade was divided into two main parts which are opaque and glazing surface elements. The amount of shading area on the opaque and glazing surface was simulated using the SunTool program. In conclusion, the Case Study C had the highest average percentage of the shading area, which is 64.43%, followed by the Case Study A 60.41% and Case Study B 56.29%. These results showed that the facade designs had excellent horizontal shading elements with roof overhangs for high angle sunlight but they had weak vertical shading elements due to a lack of considerations of louvered elements to block low angle sunlight.

  12. Modeling Tree Shade Effect on Urban Ground Surface Temperature.

    Science.gov (United States)

    Napoli, Marco; Massetti, Luciano; Brandani, Giada; Petralli, Martina; Orlandini, Simone

    2016-01-01

    There is growing interest in the role that urban forests can play as urban microclimate modifiers. Tree shade and evapotranspiration affect energy fluxes and mitigate microclimate conditions, with beneficial effects on human health and outdoor comfort. The aim of this study was to investigate surface temperature () variability under the shade of different tree species and to test the capability in predicting of a proposed heat transfer model. Surface temperature data on asphalt and grass under different shading conditions were collected in the Cascine park, Florence, Italy, and were used to test the performance of a one-dimensional heat transfer model integrated with a routine for estimating the effect of plant canopies on surface heat transfer. Shading effects of 10 tree species commonly used in Italian urban settings were determined by considering the infrared radiation and the tree canopy leaf area index (LAI). The results indicate that, on asphalt, was negatively related to the LAI of trees ( reduction ranging from 13.8 to 22.8°C). On grass, this relationship was weaker probably because of the combined effect of shade and grass evapotranspiration on ( reduction ranged from 6.9 to 9.4°C). A sensitivity analysis confirmed that other factors linked to soil water content play an important role in reduction of grassed areas. Our findings suggest that the energy balance model can be effectively used to estimate of the urban pavement under different shading conditions and can be applied to the analysis of microclimate conditions of urban green spaces. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  13. A mathematical model of shading rows of plants

    Energy Technology Data Exchange (ETDEWEB)

    Tar, K.; Makra, L.; Loki, J. [L. Kossuth University, Debrecen (Hungary)

    1998-04-01

    This paper reviews a previous analysis on the shading of buildings and applies the same principles to applications in agriculture, e.g. the shading of rows of plants. The new model is applicable to vertical parallel rows of plants, such as the cordon-trained grapevine, aligned in any direction and on either horizontal or inclined slopes. At any particular plantation, information for optimal planting procedures could be determined. The plants could make a much greater use of solar energy compared with conventional procedures, with enhanced quality and quantity. (author)

  14. The perception of shape from shading in a new light

    OpenAIRE

    Proulx, Michael J.

    2014-01-01

    How do humans see three-dimensional shape based on two-dimensional shading? Much research has assumed that a ‘light from above’ bias solves the ambiguity of shape from shading. Counter to the ‘light from above’ bias, studies of Bayesian priors have found that such a bias can be swayed by other light cues. Despite the persuasive power of the Bayesian models, many new studies and books cite the original ‘light from above’ findings. Here I present a version of the Bayesian result that can be exp...

  15. USGS Small-scale Dataset - 100-Meter Resolution Grayscale Shaded Relief of Hawaii 201304 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Grayscale Shaded Relief of Hawaii map layer is a 100-meter resolution grayscale shaded relief image of Hawaii, in an Albers Equal-Area Conic projection. Shaded...

  16. USGS Small-scale Dataset - 100-Meter Resolution Grayscale Shaded Relief of Alaska 201304 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Grayscale Shaded Relief of Alaska map layer is a 100-meter resolution grayscale shaded relief image of Alaska, in an Albers Equal-Area Conic projection. Shaded...

  17. 100-Meter Resolution Grayscale Shaded Relief of the Conterminous United States - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Grayscale Shaded Relief of the Conterminous United States map layer is a 100-meter resolution grayscale shaded relief image of the United States, in an Albers...

  18. Differences in tooth shade value according to age, gender and skin color: A pilot study.

    Science.gov (United States)

    Veeraganta, Sumanth K; Savadi, Ravindra C; Baroudi, Kusai; Nassani, Mohammad Z

    2015-01-01

    The purpose was to investigate the differences in tooth shade value according to age, gender and skin color among a sample of the local population in Bengaluru, India. The study comprised 100 subjects belonging to both gender between the age groups of 16 years to 55 years. Tooth shade values of permanent maxillary left or right central incisors were recorded using the Vitapan 3D-Master shade guide. Skin color was matched using the Radiance compact makeup shades as a guide. Chi-square statistical test demonstrated that younger subjects have lighter tooth shade values. No statistically significant differences were recorded in tooth shade value according to gender or skin color. Within the limitations of the current study, it can be concluded that tooth shade value is significantly influenced by age. Gender and skin color appear not to have a significant relation to tooth shade value.

  19. 100-Meter Resolution Satellite View with Shaded Relief of Hawaii - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Satellite View with Shaded Relief of Hawaii map layer is a 100-meter resolution simulated natural-color image of Hawaii, with relief shading added to accentuate...

  20. 100-Meter Resolution Color Shaded Relief of the Conterminous United States - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Color Shaded Relief of the Conterminous United States map layer is a 100-meter resolution color-sliced elevation image of the United States, with relief shading...

  1. USGS Small-scale Dataset - Bathymetric Shaded Relief of North America 200509 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Bathymetric Shaded Relief of North America map layer shows depth ranges using colors, with relief enhanced by shading. The image was derived from the National...

  2. Multifunctional shade-tree management in tropical agroforestry landscapes — a review

    National Research Council Canada - National Science Library

    Teja Tscharntke; Yann Clough; Shonil A. Bhagwat; Damayanti Buchori; Heiko Faust; Dietrich Hertel; Dirk Hölscher; Jana Juhrbandt; Michael Kessler; Ivette Perfecto; Christoph Scherber; Götz Schroth; Edzo Veldkamp; Thomas C. Wanger

    2011-01-01

    .... Adaptation strategies to environmental change include maintenance of shade trees in tropical agroforestry, but conversion of shaded to unshaded systems is common practice to increase short-term yield. 2...

  3. Difference in illuminant-dependent color changes of shade guide tabs by the shade designation relative to three illuminants.

    Science.gov (United States)

    Cha, Hyun-Suk; Lee, Yong-Keun

    2009-12-01

    To determine the difference in illuminant-dependent color changes of shade guide tabs of Vita Lumin (VITA), Chromascop (CHRO) and Vita 3D-Master (3D-M) shade guides by the shade designation in each shade guide. Color of 16 tabs of VITA, 20 tabs of CHRO and 29 tabs of 3D-M was measured according to the CIELAB color scale relative to the CIE standard illuminant D65, A and F2. Color differences (deltaE*ab) between the A1 tab and other VITA tabs, between the 110 tab and other CHRO tabs and between the 0M1 tab and other 3D-M tabs relative to the three illuminants were calculated, and the ratios of deltaE*ab values relative to the different illuminants [deltaE*ab(A)/deltaE*ab(D65), deltaE*ab(F2)/deltaE*ab(D65) and deltaE*ab(F2)/deltaE*ab(A)] were calculated. Ratios of the hue angle shifts of each shade tab by the change of illuminant over the corresponding value of the Al, the 110 or the 0M1 tab were also calculated. Differences in the ratios of color difference and hue angle shift were analyzed with a repeated measures, two-way analysis of variance (alpha = 0.05). Ratios of deltaE*ab values by the illuminant were 0.90-1.17, 0.95-1.07 and 0.99-1.06 for the VITA, the CHRO and the 3D-M shade guide, respectively. Ratios of the hue angle shifts by the illuminant were from -1.6 to 1.8 for the VITA, from -7.3 to 1.2 for the CHRO and from -1.2 to 3.1 for the 3D-M. Changes in color and hue angle of shade tabs were significantly different by the shade tab designation when illuminant was changed (P < 0.01).

  4. In vivo spectroradiometric evaluation of colour matching errors among five shade guides.

    Science.gov (United States)

    Li, Q; Yu, H; Wang, Y N

    2009-01-01

    The purpose of this study was to evaluate the colour errors of visual shade selection by five different shade guides. The maxillary left central incisors of sixty participants were visually evaluated by two groups of prosthodontists, with different clinical experience. The shade selection results were recorded and the most selected tab was determined as the resultant shade for each tooth. If totally different opinions were obtained, consensus was needed to determine the resultant shade among the observers. The colour distributions (L*, a* and b*) of each tooth and shade tab were measured using a spectroradiometer. The coverage errors (CEs) of each shade guide and colour differences (DeltaE values) between a tooth and the selected shade tabs were calculated. Two-way anova and Tukey's post hoc analysis were used to evaluate the differences of CE and DeltaE values among shade guides and clinical experience (alpha = 0.05). Coverage errors and DeltaE values in all of the five shade guide systems were all beyond the clinical threshold of 3.3 units. The consensus led to a better colour matching than that of the single decision group in Vitapan 3D-Master and Shofu NCC shade guides. A significant difference (P < 0.001) was found among DeltaE values of the shade guide system and clinical experience. In conclusion, all five of the shade guide systems used did not achieve clinically compatible shade matching. However, the Vitapan 3D Master shade guide system resulted in the lowest CEs and DeltaE values. Consensus could be helpful in enhancing the aesthetic results using Vitapan 3D Master and Shofu NCC shade guides.

  5. Crafting tolerance

    DEFF Research Database (Denmark)

    Kirchner, Antje; Freitag, Markus; Rapp, Carolin

    2011-01-01

    Ongoing changes in social structures, orientation, and value systems confront us with the growing necessity to address and understand transforming patterns of tolerance as well as specific aspects, such as social tolerance. Based on hierarchical analyses of the latest World Values Survey (2005–08...... results show that specific institutional qualities, which reduce status anxiety, such as inclusiveness, universality, and fairness, prevail over traditional socio-economic, societal, cultural, and democratic explanations.......–08) and national statistics for 28 countries, we assess both individual and contextual aspects that influence an individual's perception of different social groupings. Using a social tolerance index that captures personal attitudes toward these groupings, we present an institutional theory of social tolerance. Our...

  6. Spectral quality of the shading and spacing on alpinia cultivation

    Directory of Open Access Journals (Sweden)

    Roseane Rodrigues de Souza

    2016-09-01

    Full Text Available Intensity and spectral quality of the radiation can be manipulated with the use of neutral or color shading screens in growing plants, and it can promote physiological and morphological changes. Therefore, the purpose was evaluating the effects of different shading levels, screens spectral quality, and spacing in the development of cv. Jungle King and cv. Jungle Queen gingers. Rhizomes were planted in 5 cultivation environments (full sun, black screen 50%, black screen 30%, blue screen 50% and red screen 50% shading and 2 spacing (0.8 x 1.0 m and 0.8 x 1.5 m. The experimental design was completely randomized in a factorial 5x2x2x7, with 5 environments of cultivation, 2 cultivars, 2 spacing between plants and 7 times of evaluation (55, 120, 200, 255, 285, 335 e 370 days after planting (DAP. The evaluations were shooting index, number of shoots per plant, shoot height and number of leaves per shoot. Shooting of cv. Jungle Queen was earlier compared to cv. Jungle King. Spacing did not influence in the initial development of plants. Screens with 50% shading, in blue or red colors, enhanced alpinia development.

  7. Bird communities in sun and shade coffee farms in Kenya

    Directory of Open Access Journals (Sweden)

    C. Smith

    2015-07-01

    Full Text Available Agricultural expansion to meet rising crop demand is one of the greatest threats to terrestrial biodiversity. Coffee, one of the most valuable trade items in tropical countries, can provide both economic livelihood and wildlife habitat. Previous work, conducted primarily on Neotropical coffee farms, indicates that birds are generally more abundant and diverse in farms with a canopy of shade trees, though regional variation exists. To date, few studies have examined birds on coffee farms in Africa, which contains 20% of the world’s coffee acreage. We studied differences in the bird communities between sun and shade monoculture coffee in central Kenya, and we examined effects of vegetation on bird abundance and diversity. Sun coffee had higher species richness and abundances of all major guilds (omnivores, insectivores, and granivores, and showed low community similarity to shade. Unlike findings from the Neotropics, canopy cover appeared to have a negative influence on all guilds, while understory volume of weeds increased bird abundance and species richness with a similar magnitude as canopy cover. These differences highlight the need for further studies in the general East Africa region with a wider variety of shade coffee systems.

  8. [The influence of toothguide training box on shade matching veracity].

    Science.gov (United States)

    Xu, Ming-ming; Xu, Tong-kai; Liu, Feng; Shi, Xiao-rui; Feng, Hai-lan

    2009-08-01

    The aim of the study was to evaluate the influence of toothguide training box(TTB) on shade matching veracity, and compare the differences of influence on shade matching veracity of tabs of shadeguide and on that of tabs out of shadeguide. 31 graduated students who had 1 to 5-year clinical experience without color blindness were trained by TTB once a week for 3 weeks. Elapsed time and scores from the training system were recorded each time. And everyone was tested by 29 tabs of Vita 3D-Master shadeguide and 7 tabs out of Vita 3D-Master shadeguide before the first training as the base line and tested again after the last training as the test after training. SPSS 10.0 software package was used for analysis. The variances of scores and elapsed time were analyzed by ANOVA, and the differences of veracity between tabs of shadeguide and that of tabs out of shadeguide by Wilcoxon signed ranks test. The scores of the tests were rising via training. There was significant difference (P0.01). TTB can improve the shade matching ability of prosthodontists, but has limited influence on the shade matching ability of tabs out of shadeguide.

  9. MODELLING AND CONTROL OF PARTIALLY SHADED PHOTOVOLTAIC ARRAYS

    Directory of Open Access Journals (Sweden)

    Chia Seet Chin

    2013-01-01

    Full Text Available The photovoltaic (PV array controlled by Maximum Power Point Tracking (MPPT method for optimum PV power generation, particularly when the PV array is under partially shaded condition is presented in this paper. The system modelling is carried out in MATLAB-SIMULINK where the PV array is formed by five series connected identical PV modules. Under uniform solar irradiance conditions, the PV module and the PV array present nonlinear P-V characteristic but the maximum power point (MPP can be easily identified. However, when the PV array is under shaded conditions, the P-V characteristic becomes more complex with the present of multiple MPP. While the PV array operated at local MPP, the generated power is limited. Thus, the investigation on MPPT approach is carried out to maximize the PV generated power even when the PV array is under partially shaded conditions (PSC. Fuzzy logic is adopted into the conventional MPPT to form fuzzy logic based MPPT (FMPPT for better performance. The developed MPPT and FMPPT are compared, particularly the performances on the transient response and the steady state response when the array is under various shaded conditions. FMPPT shows better performance where the simulation results demonstrate FMPPT is able to facilitate the PV array to reach the MPP faster while it helps the PV array to produce a more stable output power.

  10. The use of shaded fuelbreaks in landscape fire management

    Science.gov (United States)

    James K. Agee; Bernie Bahro; Mark A. Finney; Philip N. Omi; David B. Sapsis; Carl N. Skinner; Jan W. van Wagtendonk; C. Phillip Weatherspoon

    2000-01-01

    Shaded fuelbreaks and larger landscape fuel treatments, such as prescribed fire, are receiving renewed interest as forest protection strategies in the western United States. The effectiveness of fuelbreaks remains a subject of debate because of differing fuelbreak objectives, prescriptions for creation and maintenance, and their placement in landscapes with differing...

  11. Evaluating Accuracy of the Sunnova Pro Platform Shade Measurement

    Energy Technology Data Exchange (ETDEWEB)

    2018-01-11

    Sunnova's new solar energy design platform, Sunnova Pro, automatically generates a 3D model of a building and surrounding shading objects. The product is designed to automate the process of engineering a system, sizing batteries and preparing sales proposals.

  12. Adaptive heating, ventilation and solar shading for dwellings

    NARCIS (Netherlands)

    Alders, E.E.

    2017-01-01

    Calculation of various strategies for the heating of, and the prevention of overheating in, a Dutch standard dwelling that includes (automated) adaptive ventilation systems and solar shading to maintain indoor temperatures at acceptably comfortable temperatures informs this analysis of the costs,

  13. Effects of shading and covering material application for delaying ...

    African Journals Online (AJOL)

    Based on the results of this study, the highest gray mold (Botrytis cinerea) severity was obtained in the control (uncovered and unshaded) treatment and the lowest disease severity was observed in lifepack treatment with or without shading. Since gray mold disease of grape was the main factor affecting harvest date of the ...

  14. Effect of shading and fertilisation on the development of container ...

    African Journals Online (AJOL)

    Effect of shading and fertilisation on the development of container-grown Nothofagus glauca seedlings, a threatened species from central Chile. Rómulo Santelices, Sergio Espinoza, Antonio Cabrera Ariza, Karen Peña-Rojas, Sergio R Donoso ...

  15. Reliability of shade selection using an intraoral spectrophotometer.

    Science.gov (United States)

    Witkowski, Siegbert; Yajima, Nao-Daniel; Wolkewitz, Martin; Strub, Jorge R

    2012-06-01

    In this study, we evaluate the accuracy and reproducibility of human tooth shade selection using a digital spectrophotometer. Variability among examiners and illumination conditions were tested for possible influence on measurement reproducibility. Fifteen intact anterior teeth of 15 subjects were evaluated for their shade using a digital spectrophotometer (Crystaleye, Olympus, Tokyo, Japan) by two examiners under the same light conditions representing a dental laboratory situation. Each examiner performed the measurement ten times on the labial surface of each tooth containing three evaluation sides (cervical, body, incisal). Commission International on Illumination color space values for L* (lightness), a* (red/green), and b* (yellow/blue) were obtained from each evaluated side. Examiner 2 repeated the measurements of the same subjects under different light conditions (i.e., a dental unit with a chairside lamp). To describe measurement precision, the mean color difference from the mean metric was used. The computed confidence interval (CI) value 5.228 (4.6598-5.8615) reflected (represented) the validity of the measurements. Least square mean analysis of the values obtained by examiners 1 and 2 or under different illumination conditions revealed no statistically significant differences (CI = 95%). Within the limits of the present study, the accuracy and reproducibility of dental shade selection using the tested spectrophotometer with respect to examiner and illumination conditions reflected the reliability of this device. This study suggests that the tested spectrophotometer can be recommended for the clinical application of shade selection.

  16. Effect of Color Shading Procedures and Cyclic Loading on the ...

    African Journals Online (AJOL)

    2018-02-07

    5 days ago ... Effect of Color Shading Procedures and Cyclic Loading on the Biaxial. Flexural Strength of Zirconia. I Tuncel, I Turp, A Usumez masking liner material, which is applied before layering the veneer ceramic.[2] Current studies has reported that coloring procedures affect the structure of the zirconia framework.

  17. The different shades of mammalian pluripotent stem cells

    NARCIS (Netherlands)

    Kuijk, E.W.|info:eu-repo/dai/nl/304834459; Lopes, S.M.; Geijsen, N.|info:eu-repo/dai/nl/194303403; Macklon, N.S.; Roelen, B.A.J.|info:eu-repo/dai/nl/109291859

    2011-01-01

    The different shades of mammalian pluripotent stem cells Abstract BACKGROUND Pluripotent stem cells have been derived from a variety of sources such as from the inner cell mass of preimplantation embryos, from primordial germ cells, from teratocarcinomas and from male germ cells. The recent

  18. Matching Shades of Forest Environment to sustain Crude Fibre and ...

    African Journals Online (AJOL)

    Five different types of shades were employed as experimental treatments using the Randomized Complete Block Design (RCBD). The natural forest condition served as a control. Samples of the edible parts from the domesticated and wild Vegetables were harvested for laboratory analysis for calcium, zinc, iron and crude ...

  19. Influence of shade systems on spatial distribution and infestation of ...

    African Journals Online (AJOL)

    ACSS

    designing appropriate sampling techniques and effective Integrated Pest. Management (IPM) strategies (Chong .... under umbrella tree shade (Table 6). Discussion. Understanding spatial distribution of X. compactus ..... infestation and population dynamics before any authoritative conclusion is drawn. In our study, it is most ...

  20. Om tolerance

    DEFF Research Database (Denmark)

    Huggler, Jørgen

    2007-01-01

    Begrebet tolerance og dets betydninger diskuteres med henblik på en tydeliggørelse af begrebets forbindelse med stat, religion, ytringsfrihed, skeptisk erkendelsesteori, antropologi og pædagogik.......Begrebet tolerance og dets betydninger diskuteres med henblik på en tydeliggørelse af begrebets forbindelse med stat, religion, ytringsfrihed, skeptisk erkendelsesteori, antropologi og pædagogik....

  1. Effect of shade on various parameters of Friesian cows in a ...

    African Journals Online (AJOL)

    The effect of a shade structure on the feed intake, water intake, milk production and milk composition of Dutch-type. Friesian cows in a temperate climate was determined over three summer seasons. The shade structure reduced. (P < 0.01) radiation as wzrs indicated by lower black globe temperatures. Feed intake of shade ...

  2. [Coverage errors of five shade guide systems to vital natural teeth].

    Science.gov (United States)

    Chen, Li; Tan, Jian-guo; Liu, Ming-yue; Zhou, Jian-feng; Liu, Xiao-qiang

    2013-08-01

    To compare the coverage errors (CE) of five different shade guides in anterio vital natural teeth of selected people. Anterior vital natural teeth were measured with Crystaleye spectrophotometer, color coordinates of the teeth and five shade guides A (VITA Classical), B (VITA 3D-Master), C (Chromascop), D (Shofu Vintage Halo NCC) and E (Noritake)were analyzed with the supporting software. The CE of the five shade guide systems to natural teeth were evaluated in cervical, body and incisal regions, and difference in CE among shade guides was determined. In the cervical region, shade guide A had the maximal CE value (3.09 ± 0.97) and shade guide D had the minimal CE value (1.62 ± 0.75).In the body region, CE of shade guide B (1.65 ± 0.64) and shade guide D (1.52 ± 0.74) were lower than those of shade guides A (2.04 ± 0.80), C (2.04 ± 0.90) and E (2.02 ± 0.84) (P < 0.05).In the incisal part, all CE were below 2.00, and again shade guide A had the maximal CE value (1.81 ± 0.86) and shade guide D had the minimal CE value (1.28 ± 0.55). Within the limitation of the study, shade guide D had better color coverage of natural teeth in cervical, body and incisal regions.

  3. Effect of different moisture and shade regimes on the growth of D x P ...

    African Journals Online (AJOL)

    Data was collected on leaf number per plant, plant height, butt circumference and leaf area as well as dry weight of plant parts and total dry matter. There were significant effects due to shade and shade x moisture interactions on seedling growth. Seedlings under 50% shade (50% full sunlight) in combination with low ...

  4. Effect of shade on various parameters of Friesian cows in a ...

    African Journals Online (AJOL)

    The effect of a shade structure on some physiological parameters of lactating Dutch-type Friesian cows wurs determined over three consecutive summer periods. Plasma cortisol concentration of no-shade cows was significantly. (P < 0.05) higher than that of shade cows during the 1985/86 experimentalperiod as well as the ...

  5. Shading responses of carbon allocation dynamics in mountain grassland

    Science.gov (United States)

    Bahn, M.; Lattanzi, F. A.; Brueggemann, N.; Siegwolf, R. T.; Richter, A.

    2012-12-01

    Carbon (C) allocation strongly influences plant and soil processes. Global environmental changes can alter source - sink relations of plants with potential implications for C allocation. Short-term C allocation dynamics in ecosystems and their responses to environmental changes are still poorly understood. To analyze effects of assimilate supply (i.e. C source strength) on ecosystem C allocation dynamics and the role of non-structural carbohydrates, canopy sections of a mountain meadow were pulse labeled with 13CO2 and subsequently shaded for a week or left unshaded (control). Tracer dynamics in above- and belowground sucrose and starch pools were analysed and coupled using compartmental modelling. The hypothesis was tested that shading affects tracer dynamics in non-structural carbohydrates and diminishes the transfer of recently assimilated C to roots and their storage pools. In unshaded plots up to 40% of assimilated C was routed through short-term storage in shoot starch and sucrose to buffer day / night cycles in photosynthesis. Shoot- and root sucrose and shoot starch were kinetically closely related pools. The tracer dynamics of the modelled root sucrose pool corresponded well with those in soil CO2 efflux. Root starch played no role in buffering day / night cycles and likely acted as a seasonal store. Shading strongly reduced sucrose and starch concentrations in shoots but not roots and resulted in a massive reduction of leaf respiration, while root respiration was much less diminished. Shading affected tracer dynamics in sucrose and starch of shoots: shoot starch rapidly lost tracer, while sucrose transiently increased its tracer content. Surprisingly, shading did not alter the dynamics of root carbohydrates. Even under severe C limitation after one week of shading, tracer C continued to be incorporated in root starch. Also the amount of 13C incorporated in phospholipid fatty acids of soil microbial communities was not reduced by shading, though its

  6. Shading correction assisted iterative cone-beam CT reconstruction

    Science.gov (United States)

    Yang, Chunlin; Wu, Pengwei; Gong, Shutao; Wang, Jing; Lyu, Qihui; Tang, Xiangyang; Niu, Tianye

    2017-11-01

    Recent advances in total variation (TV) technology enable accurate CT image reconstruction from highly under-sampled and noisy projection data. The standard iterative reconstruction algorithms, which work well in conventional CT imaging, fail to perform as expected in cone beam CT (CBCT) applications, wherein the non-ideal physics issues, including scatter and beam hardening, are more severe. These physics issues result in large areas of shading artifacts and cause deterioration to the piecewise constant property assumed in reconstructed images. To overcome this obstacle, we incorporate a shading correction scheme into low-dose CBCT reconstruction and propose a clinically acceptable and stable three-dimensional iterative reconstruction method that is referred to as the shading correction assisted iterative reconstruction. In the proposed method, we modify the TV regularization term by adding a shading compensation image to the reconstructed image to compensate for the shading artifacts while leaving the data fidelity term intact. This compensation image is generated empirically, using image segmentation and low-pass filtering, and updated in the iterative process whenever necessary. When the compensation image is determined, the objective function is minimized using the fast iterative shrinkage-thresholding algorithm accelerated on a graphic processing unit. The proposed method is evaluated using CBCT projection data of the Catphan© 600 phantom and two pelvis patients. Compared with the iterative reconstruction without shading correction, the proposed method reduces the overall CT number error from around 200 HU to be around 25 HU and increases the spatial uniformity by a factor of 20 percent, given the same number of sparsely sampled projections. A clinically acceptable and stable iterative reconstruction algorithm for CBCT is proposed in this paper. Differing from the existing algorithms, this algorithm incorporates a shading correction scheme into the low

  7. Behavioral ecology of Heteragrion consors Hagen (Odonata, Megapodagrionidae: a shade-seek Atlantic forest damselfly

    Directory of Open Access Journals (Sweden)

    Geovanni Ribeiro Loiola

    2011-09-01

    Full Text Available Behavioral ecology of Heteragrion consors Hagen (Odonata: Megapodagrionidae: a shade-seek Atlantic forest damselfly. The intensity of the inter and intra-sexual selection can affect male behavioral traits as territorial fidelity and aggressiveness allowing the existence of different strategies. However, its differential success could be affected by environmental - as the diel variation in temperature - and physiological constrains - as the variation in thermoregulatory abilities. In this context, we present a behavioral analysis of Heteragrion consors (Zygoptera, Megapodagrionidae trying to characterize its mating system, diel activity pattern, temporal budget, territoriality and reproductive biology. These data were obtained based on field observations using the focal individual method and mark-recapture techniques in 120 m of a shaded Atlantic Forest stream in Brazil. The males of this species were territorial, varying in its local fidelity, while the females appear sporadically. Males were perched in the majority of the time, but were also observed in cleaning movements, longitudinal abdominal flexion, wing flexion and sperm transfer during perch. The males presented a perched thermoregulatory behavior related to an exothermic regulation. Foraging and agonistic interactions were rare, but dominate the other behavioral activities. Abdominal movements associated to long lasting copula pointed to the existence of sperm competition in this species. Males performed contact post-copulatory guarding of the females. These observations pointed to a non-resource mating system for this species.

  8. MPPT Schemes for PV System under Normal and Partial Shading Condition: A Review

    Directory of Open Access Journals (Sweden)

    Malik Sameeullah

    2016-08-01

    Full Text Available The photovoltaic system is one of the renewable energy device, which directly converts solar radiation into electricity. The I-V characteristics of PV system are nonlinear in nature and under variable Irradiance and temperature, PV system has a single operating point where the power output is maximum, known as Maximum Power Point (MPP and the point varies on changes in atmospheric conditions and electrical load. Maximum Power Point Tracker (MPPT is used to track MPP of solar PV system for maximum efficiency operation. The various MPPT techniques together with implementation are reported in literature. In order to choose the best technique based upon the requirements, comprehensive and comparative study should be available. The aim of this paper is to present a comprehensive review of various MPPT techniques for uniform insolation and partial shading conditions. Furthermore, the comparison of practically accepted and widely used techniques has been made based on features, such as control strategy, type of circuitry, number of control variables and cost. This review work provides a quick analysis and design help for PV systems. Article History: Received March 14, 2016; Received in revised form June 26th 2016; Accepted July 1st 2016; Available online How to Cite This Article: Sameeullah, M. and Swarup, A. (2016. MPPT Schemes for PV System under Normal and Partial Shading Condition: A Review. Int. Journal of Renewable Energy Development, 5(2, 79-94. http://dx.doi.org/10.14710/ijred.5.2.79-94 

  9. Insect succession and decomposition patterns on shaded and sunlit carrion in Saskatchewan in three different seasons.

    Science.gov (United States)

    Sharanowski, Barbara J; Walker, Ernest G; Anderson, Gail S

    2008-08-06

    A study was conducted on decomposition and insect succession in the Prairie Ecozone of Saskatchewan in the year 2000. Eighteen domestic pig carcasses (42-79 kg) were employed as human models for applications to future homicide investigations in this region. Two major variables were considered including the effect of season and habitat (sun versus shade). Research was conducted over 25 weeks, spanning three seasons: spring, summer and fall. Ambient temperature, internal carcass temperature, faunistic succession over time, and the rate of decay were all compared for each experimental variable. Results indicated that habitat was only a factor in the decompositional rate of carrion in the spring season. The ambient temperature was the chief factor determining the seasonal variations in decay rate. Maximum internal carcass temperatures always coincided with the presence of 3rd instar larvae. Patterns of insect succession occurred in a predictable sequence that varied across different habitats and seasons and was unique compared to previously published studies. Carcasses placed in spring and fall attracted a more diverse assemblage of insects than summer-placed carrion. Sun-exposed carrion also had greater variation in fauna than shaded carrion in spring and fall. Members of Silphidae were the first coleopteran colonizers in all habitats and seasons. This paper also marks the first record for Cochliomyia macellaria (Fabricius) in Saskatchewan.

  10. [Effects of shading light quality at seedling stage on the photosynthesis and growth of ginger].

    Science.gov (United States)

    Zhang, Rui-Hua; Xu, Kun

    2008-03-01

    With different color plastic films as shading materials, this paper studied the effects of shading light quality at seedling stage on the growth and photosynthesis of ginger. The results showed that shading with green or blue film induced the greatest chlorophyll content in ginger leaves, followed by shading with white film, and red film. In parallel, the photosynthetic rate under green film-shading was the highest, being 14.9 micromol x m(-2) x s(-1) in the 4th leaves, which was 5.7%, 10.4%, and 18.3% higher than that under white, red, and blue film-shading, respectively. After removing the films at vigorous growth stage, the photosynthetic rate became larger, and its change pattern in different shading treatments was similar to that at seedling stage. No significant differences in the chlorophyll content of young leaves were observed among the shading treatments, except the low chlorophyll content under red film-shading. In contrast, the chlorophyll content in low position leaves under blue and red film-shading was lower than that under green and white film-shading. In the whole growth period, the plants under blue film-shading were higher in height and with thinner stem and lesser shoot, compared with those shaded with other color films. The fresh mass of root, stem, leaf, and rhizome decreased in the order of green, white, red, and blue film-shading, and the yields at harvesting stage were 57,000, 53,709, 51,487, and 48,712 kg x hm(-2), respectively, illustrating that shading with green film at seedling stage could increase the leaf photosynthesis, plant growth, and yield of ginger.

  11. Influence of surface layer removal of shade guide tabs on the measured color by spectrophotometer and spectroradiometer.

    Science.gov (United States)

    Kim, Jin-Cheol; Yu, Bin; Lee, Yong-Keun

    2008-12-01

    To determine the changes in color parameters of Vitapan 3D-Master shade guide tabs by a spectrophotometer (SP) or a spectroradiometer (SR), and by the removal of the surface layer of the tabs that was performed to make a flat measuring surface for the SP color measurement. Color of the shade tabs was measured before and after removing the surface layer of the tabs using SP and SR. Correlations between the color parameters between the original (OR) and the surface layer removed (RM) tabs and between the SP and the SR measurements were determined (alpha=0.05). Based on SP, the lightness, chroma, CIE a* and b* values measured after the surface layer removal were higher than those of the original tabs except a few cases. Based on SR, the chroma and CIE a* and b* values measured after surface layer removal were higher than those of the original tabs except a few cases; however, in case of the lightness, the changes varied by the shade designation. Type of instrument influenced the changes in color parameters based on paired t-test (pspectrophotometer or a spectroradiometer, measurement protocols should be specified because color difference by the surface layer removal and the instrument was high.

  12. Efeito da sombra natural e da tosquia no comportamento de ovelhas das raças Texel e Hampshire Down, ao longo do período diurno, no Noroeste do Estado do Paraná Effect of natural shade and shearing on the behavior of Texel and Hampshire Down sheep during the day period in the northwestern region of Paraná

    Directory of Open Access Journals (Sweden)

    Walber Mendonça Onorato

    2001-05-01

    Full Text Available Durante 12 meses, divididos em estações quente e fria, durante três dias mensais, das 6 às 18 h, registraram-se os comportamentos ligados ao pastejo, ruminação e ócio ao sol e à sombra, respectivamente, e frequência ao bebedouro em 16 ovelhas, com idade entre três e quatro anos, sendo oito da raça Texel e oito Hampshire Down, tosquiando-se quatro animais por raça. Avaliou-se a quantidade de folhas verdes, proteína bruta e FDA da pastagem. Os dados climáticos foram registrados a cada hora e a precipitação, mensalmente. A busca de sombra elevou-se devido ao aumento da radiação solar. O bosque de grevíleas foi utilizado na busca de sombra, bem como no consumo da folhagem. No piquete, com bosque de eucalipto, apenas a sombra da instalação foi utilizada. As condições da pastagem e as variáveis climáticas podem ter alterado o comportamento. Os animais tosquiados foram mais tolerantes ao sol. As raças apresentaram-se adaptadas à região, destacando a importância de bosques.The behavior of 16 sheep was reported during a twelve-month period, comprising hot and cold seasons, for three days each month, from 6 to18h. The eight Texel and eight Hampshire Down sheep, aged three and four years, were analyzed with regard to grazing, rumination, resting in the sun and in the shade, respectively, and watering. Four animals of each breed were sheared. Quantity of green leaves, crude protein and pasture FDA were analyzed. Climate data were reported hourly and rainfall monthly. Rise in shade seeking was recorded in proportion to increase in solar radiation. Silk oak grove was used for shade and leaf consumption. Only the shade of the pen in the eucalyptus grove was used. Grazing conditions and climatic variables may have changed sheep’s behavior. Sheared animals were more tolerant to the sunrays. Although breeds have adapted themselves extremely well to the region, the importance of groves must be enhanced.

  13. Typology of building shading elements on Jalan Sudirman corridor in Pekanbaru

    Science.gov (United States)

    Faisal, G.; Aldy, P.

    2016-04-01

    In 2013, temperature in Pekanbaru was between 22.60°C and 34.6°C with humidity 79.14 percent. This condition has increase the concern of energy utilization to building comfort. Buildings have the biggest energy consuming due to the use of air conditioner in Pekanbaru. One effort to reduced energy is shading devices application. Application of air conditioner need huge energy, replaced natural circulation with architecture elements to reduced building thermal. This research study about system and building shading devices types that influence building thermal in Pekanbaru so that knowing characteristics and elements form. This study aims to determine and identify of systems and building elements types in Pekanbaru, which the element forms to conquer in climate condition. Qualitative method with rationalistic-paradigm has used to identify typology of building shading devices on Jalan Sudirman corridor. The research orientation on typology theory, thermal theory, and building shading device to identification of building shading device types on Jalan Sudirman corridor. Based on the survey result, there are 2 type of building shading devices on Jalan Sudirman Pekanbaru which is based on forms and quantity of shading. The types are building shading devices based on shading quantity and building shading devices based on shading forms.

  14. Evaluation of different shades to improve dairy cattle well-being in Argentina

    Science.gov (United States)

    Valtorta, S. E.; Leva, Perla E.; Gallardo, Miriam R.

    Two tree shades (TS1 and TS2) and an artificial shade structure (AS) were evaluated using black globe temperatures (BGTs) to assess their effectiveness in reducing heat load. The artificial structure consisted of a black woven polypropylene cloth providing 80% shade, mounted on 2.5-m-high eucalyptus posts. The work was carried out at Rafaela Experimental Station, Argentina, during the summer (January and February) 1994. BGTs and floor temperatures were measured in concrete floor holding pens with and without artifical shade. The results showed no difference between TS1, TS2 and AS, their average BGTs being 30.2 (SD 0.58), 29.0 (SD 0.70) and 30.2 (SD 0.74)°C, respectively. BGTs under all three shades were significantly lower (Pcows were recorded twice a week. Rectal temperatures were significantly higher for non-shaded cows (P<0.01), mean RT being 40.1 (SD 0.65)°C vs 39.3 (SD 0.42)°C for the shaded animals. Corresponding RRs were 78.9 (SD 18.0) and 60.7 (SD 10.6) (P<0.05). It was concluded that: (1) tree and artificial shades produced similar effects, (2) shading the holding pen with an 80% shading cloth was effective in reducing heat load and floor temperatures, and (3) access to shade in our pasture-based system improved animal well-being.

  15. Building Applications, Opportunities and Challenges of Active Shading Systems: A State-of-the-Art Review

    Directory of Open Access Journals (Sweden)

    Joud Al Dakheel

    2017-10-01

    Full Text Available Active shading systems in buildings have emerged as a high performing shading solution that selectively and optimally controls daylight and heat gains. Active shading systems are increasingly used in buildings, due to their ability to mainly improve the building environment, reduce energy consumption and in some cases generate energy. They may be categorized into three classes: smart glazing, kinetic shading and integrated renewable energy shading. This paper reviews the current status of the different types in terms of design principle and working mechanism of the systems, performance, control strategies and building applications. Challenges, limitations and future opportunities of the systems are then discussed. The review highlights that despite its high initial cost, the electrochromic (EC glazing is the most applied smart glazing due to the extensive use of glass in buildings under all climatic conditions. In terms of external shadings, the rotating shading type is the predominantly used one in buildings due to its low initial cost. Algae façades and folding shading systems are still emerging types, with high initial and maintenance costs and requiring specialist installers. The algae façade systems and PV integrated shading systems are a promising solution due to their dual benefits of providing shading and generating electricity. Active shading systems were found to save 12 to 50% of the building cooling electricity consumption.

  16. The impact of a shade coffee certification program on forest conservation using remote sensing and household data

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Ryo, E-mail: inter.takahashi@gmail.com [Policy Research Center, National Graduate Institute for Policy Studies, 7-22-1, Roppongi, Minato-ku, Tokyo 106-8677 (Japan); Todo, Yasuyuki, E-mail: yastodo@k.u-tokyo.ac.jp [Department of International Studies, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8563 (Japan)

    2014-01-15

    In recent years, shade coffee certification programs have attracted increasing attention from forest conservation and development organizations. The certification programs could be expected to promote forest conservation by providing a premium price to shade coffee producers. However, little is known about the significance of the conservation efforts generated by certification programs. In particular, the relationship between the impact of the certification and producer characteristics has yet to be examined. The purpose of this study, which was conducted in Ethiopia, was to examine the impact of a shade coffee certification program on forest conservation and its relationship with the socioeconomic characteristics of the producers. Remote sensing data of 2005 and 2010 was used to gauge the changes in forest area. Employing a probit model, we found that a forest coffee area being certified increased the probability of forest conservation by 19.3 percentage points relative to forest coffee areas lacking certification. We also found that although economically poor producers tended to engage in forest clearing, the forest coffee certification program had a significant impact on these producers. This result suggests that the certification program significantly affects the behaviors of economically poor producers and motivates these producers to conserve the forest. -- Highlights: • We employed the probit mode to evaluate the impact of the shade coffee certification on forest conservation in Ethiopia. • We estimated how the impact of the certification varied among producers with different characteristics. • The certification increased the probability of conserving forest by 19.3 percentage points. • Certification program motivated the economically poor producers to conserve the forest.

  17. Comparison of visual shade determination and an intra-oral dental colourimeter.

    Science.gov (United States)

    Yilmaz, B; Karaagaclioglu, L

    2008-10-01

    The choice of correct tooth shade for the fabrication of a restoration remains a challenge, even for experienced clinicians. The aim of this research was to evaluate and compare the precision of two different shade determination methods in terms of repeatability. Maxillary right central incisor of 10 patients was evaluated visually with the use of Vitapan Classical shade guide by five observers and instrumentally with the Vitapan classical shade guide values of ShadeEye NCC intra-oral colourimeter three times consecutively. The in vivo repeatability of methods were analysed with the spectrophotometric L*, a*, b* values of the shade guide (Vitapan Classical). Within the limitations of this study, the repeatability of instrumental (intra-oral dental colourimeter) and visual shade determinations were acceptable.

  18. The impact of translucent fabric shades and control strategies on energy savings and visual quality

    Science.gov (United States)

    Wankanapon, Pimonmart

    Translucent fabric shades provide opportunities for building occupants to control sunlight penetration for heat reduction, thermal comfort, and visual quality. Regulating shades affects building energy and can potentially reduce the size of mechanical cooling systems. Shades are not normally included in energy model studies during the design process, even though shades potential impact energy use. This is because the occupants normally leave shades closed a large fraction of the time, but models are generally performed with no shades. Automatic shade control is now available, so it is necessary to understand the impact of shades on visual quality and their energy saving potential in order to optimize their overall performance. There are very limited studies that have address shades and their integrated performance on energy consumption and visual quality. Most of these do not reflected modern shade types and their application. The goals of this study are: First, to determine the impact of shades on total, heating, cooling and lighting energy savings with different design and operation parameters. Second, to study and develop different automatic shade control strategies to promote and optimize energy savings and visual quality. A simulation-based approach using EnergyPlus in a parametric study provide better understanding energy savings under different shade conditions. The parametric runs addressed various building parameters such as geometry, orientation, site climate, glazing/shade properties, and shade control strategies with integrated lighting control. The impact of shades was determined for total building and space heating, cooling and lighting energy savings. The effect of shades on visual quality was studied using EnergyPlus, AGI32 and DAYSIM for several indices such as daylight glare index (DGI), work plane illuminance, luminance ratios and view. Different shade control strategies and integrated lighting control were considered with two translucent fabric

  19. Shade tolerance and suitability of tree species for planting in rubber ...

    African Journals Online (AJOL)

    The rapid increase in rubber monoculture in Xishuangbanna has resulted in extensive damage to its local ecosystem. To decrease the negative effects, the concept of the ecological-economic rubber plantation (EERP) system was proposed. The EERP entails intercropping rubber plants with other economically significant ...

  20. Resprouting as a persistence strategy of tropical forest trees: relations with carbohydrate storage and shade tolerance

    NARCIS (Netherlands)

    Poorter, L.; Kitajima, K.; Mercado, P.; Chubina, J.; Melgar, I.; Prins, H.H.T.

    2010-01-01

    Resprouting is an important persistence strategy for woody species and represents a dominant pathway of regeneration in many plant communities with potentially large consequences for vegetation dynamics, community composition and species coexistence. Most of our knowledge on resprouting strategies

  1. Color stability of shade guides after autoclave sterilization.

    Science.gov (United States)

    Schmeling, Max; Sartori, Neimar; Monteiro, Sylvio; Baratieri, Luiz

    2014-01-01

    This study evaluated the influence of 120 autoclave sterilization cycles on the color stability of two commercial shade guides (Vita Classical and Vita System 3D-Master). The specimens were evaluated by spectrophotometer before and after the sterilization cycles. The color was described using the three-dimensional CIELab system. The statistical analysis was performed in three chromaticity coordinates, before and after sterilization cycles, using the paired samples t test. All specimens became darker after autoclave sterilization cycles. However, specimens of Vita Classical became redder, while those of the Vita System 3D-Master became more yellow. Repeated cycles of autoclave sterilization caused statistically significant changes in the color coordinates of the two shade guides. However, these differences are considered clinically acceptable.

  2. Pesticide Tolerances

    Science.gov (United States)

    EPA regulates pesticides used to protect crops and sets limits on the amount of pesticide remaining in or on foods in the U.S. The limits on pesticides on foods are called tolerances in the U.S. (maximum residue limits (MRLs) in many other countries).

  3. Towards Tolerance

    NARCIS (Netherlands)

    Lisette Kuyper; Jurjen Iedema; Saskia Keuzenkamp

    2013-01-01

    Across Europe, public attitudes towards lesbian, gay and bisexual (LGB) individuals range from broad tolerance to widespread rejection. Attitudes towards homosexuality are more than mere individual opinions, but form part of the social and political structures which foster or hinder the equality

  4. Repressive Tolerance

    DEFF Research Database (Denmark)

    Pedersen, Morten Jarlbæk

    2017-01-01

    to an administrative culture of repressive tolerance of organised interests: authorities listen but only reacts in a very limited sense. This bears in it the risk of jeopardising the knowledge transfer from societal actors to administrative ditto thus harming the consultation institutions’ potential for strengthening...

  5. Tolerance Geometry.

    Science.gov (United States)

    Roberts, Fred S.

    The author cites work on visual perception which indicates that in order to study perception it is necessary to replace such classical geometrical notions as betweeness, straightness, perpendicularity, and parallelism with more general concepts. The term tolerance geometry is used for any geometry when primitive notions are obtained from the…

  6. Quality and Quantity Evaluations of Shade Grown Forages

    Science.gov (United States)

    K. P. Ladyman; M. S. Kerley; R. L. Kallenbach; H. E. Garrett; J. W. Van Sambeek; N. E. Navarrete-Tindall

    2003-01-01

    Seven legumes were grown during the summer-fall of 2000, at the Horticulture and Agroforestry Research Center (39? 01 ' N, 92? 46' W) near New Franklin, MO. The forages were grown in 7.5L white pots placed on light-colored gravel either under full sunlight, 45% sunlight, or 20% sunlight created by a shade cloth over a rectangular frame. Drip irrigation was...

  7. Bromeliads production in greenhouses associated to different shading screens

    OpenAIRE

    Holcman,Ester; Sentelhas, Paulo Cesar

    2013-01-01

    Bromeliads production in greenhouses is highly influenced by microclimate, which affects plants growth and development. Based on that, this study aimed to evaluate the influence of shading screens of different colors on microclimatic variables and Aechmea fasciata bromeliad growth in a greenhouse covered by transparent low-density polyethylene. The experiment had five treatments, with screens of different colors, inside a plastic greenhouse: thermo-reflective (T1); control without screen (T2)...

  8. [Effect of clinical experience on the shade matching accuracy].

    Science.gov (United States)

    Wu, Yi; Gao, Qing-ping; Zhang, Xiao-yu; Yang, Bao-gui; Chen, Zhi-ying; Lu, Shou-yi

    2012-12-01

    To evaluate the effect of clinical experience on the shade matching accuracy. Thirty-seven dental students (group A) who had 1 to 2 years of clinical experience and 57 dental students (group B) who didn't have clinical experience took part in this experiment. Participants were divided into two groups (TTB group and TT group) and used the Toothguide Training (TT) and Toothguide Training Box (TTB) respectively. All participants received training session once a week for 3 weeks. Before training and each time after finished training all participants were asked to identify ten unlabeled tabs which had been randomly chosen from Vita 3D-master shadeguide. SPSS 16.0 software package was used for Wilcoxon signed rank test. Before training, the accuracy rate of group A and group B was (65.67±20.4)% and (70.17±17.57)% respectively. After training, the accuracy rate of group A and group B was (78.91±22.82)% and (80.17±17.77)% respectively. No significant difference was found between group A and B, but significant difference was found between before and after training. This study shows clinical experience is not found to be a significant factor to the teeth shade matching. The training can improve the accuracy of shade matching.

  9. The Effect of Color Training of Dental Students' on Dental Shades Matching Quality.

    Science.gov (United States)

    Alfouzan, Afnan F; Alqahtani, Hussam M; Tashkandi, Esam A

    2017-09-01

    To assess the effect of color training on the dental shade matching quality of dental students of both gender and to study the need to include lectures and exercises about shade selection in the undergraduate dental curriculum. One hundred and twenty junior dental students from the College of Dentistry at King Saud University participated in the present study and were distributed randomly into four testing groups. They were asked to match the color of four target shade tabs from the VITA Linearguide 3D-MASTER. Group 1 attended a brief lecture and a training exercise about dental shade matching, Group 2 only attended the lecture, and Group 3 only performed the training exercise. Group 4 did not participate in the lecture or the training exercise and served as a control. Exact matching rates were calculated and analyzed to determine the pre- and post-test matching values. Three way repeated measures analysis of variance, paired t test, and independent t-test were used to compare shade matching quality, with a significance level of p < 0.05. There was a significant difference between the pre- and post-test values for the students' dental shade matching qualities for all of the test groups. The effectiveness of the dental shade matching training about color and dental shade matching for improving the students' shade matching quality was proven for both genders. Training can improve shade matching quality of dental students. (J Esthet Restor Dent 29:346-351, 2017). © 2017 Wiley Periodicals, Inc.

  10. The effect of experience on composite resin shade selection in comparison to a spectrophotometer

    Directory of Open Access Journals (Sweden)

    Duygu Recen

    2016-01-01

    Full Text Available OBJECTIVE: The objective of this study was to compare the shade matching ability of dentists with different experience levels in comparison to a spectrophotometer. MATERIALS AND METHOD: Participants were selected from the volunteer fourth grade students of Faculty of Dentistry, Ege University (n=100. A fifthyear undergraduate student, a research assistant with 2 years of experience and two professors of restorative dentistry with at least 10 years of experience were included in this study as observers. Ishihara color blindness test was applied to all observers before taking shades. After taking the shades with conventional method by using Vita Classical shade guide, the research assistant took the shades again with SpectroShade Micro device. Agreement on shade matches was evaluated by percentage and compared using Wilcoxon test (p0.05 and the correct match rate of the research assistant was superior to the others. Statistically significant differences were found between the fifth grade student’s shade assignments and the research assistant’s assignments as well as the device’s readings (p<0.05. CONCLUSION: Within the limitations of this study, it was concluded that shade matching is a learnable process. In order to do a correct shade match in complicated situations, dentists may refer to spectrophotometric devices.

  11. Color distribution of a shade guide in the value, chroma, and hue scale.

    Science.gov (United States)

    Ahn, Jin-Soo; Lee, Yong-Keun

    2008-07-01

    Shade tabs in a shade guide are matched to teeth in the order of value, hue, and chroma; therefore, information on the distribution of shade tabs is essential for clinical application of a shade guide. However, there is limited information on the color distribution as sorted by these 3 parameters of a recently introduced shade guide. The purposes of this study were to determine the color distributions of tabs from a shade guide in the value (CIE L*), chroma (C*(ab)), and hue scale, and to determine the distribution of step intervals between adjacent tabs by value and chroma. The color of shade tabs (n=29) from a shade guide (Vitapan 3D-Master) was measured to determine the distribution of shade tabs by the value, chroma, hue angle, and CIE a* and b* values. The distribution of the ratios of the value and the chroma of each tab, when compared with the lowest value tab or the lowest chroma tab, was also determined. The data for each color parameter were analyzed by a 3-way ANOVA with the factors of value, chroma, and hue designations of the tabs (alpha=.05). The value, chroma, hue angle, and CIE a* and b* values were influenced by the value, chroma, and hue designations of shade tabs (P3D-Master shade guide was more ordered than previously reported color distributions of other, traditional shade guides. However, the interval in the color parameters between adjacent tabs was not uniform; therefore, shade tabs spaced equally, according to the color parameters, should be studied based on the observer's response data.

  12. Shade material evaluation using a cattle response model and meteorological instrumentation

    Science.gov (United States)

    Eigenberg, Roger A.; Brown-Brandl, Tami M.; Nienaber, John A.

    2010-11-01

    Shade structures are often considered as one method of reducing stress in feedlot cattle. Selection of a suitable shade material can be difficult without data that quantify material effectiveness for stress reduction. A summer study was conducted during 2007 using instrumented shade structures in conjunction with meteorological measurements to estimate relative effectiveness of various shade materials. Shade structures were 3.6 m by 6.0 m by 3.0 m high at the peak and 2.0 m high at the sides. Polyethylene shade cloth was used in three of the comparisons and consisted of effective coverings of 100%, 60% with a silver reflective coating, and 60% black material with no reflective coating. Additionally, one of the structures was fitted with a poly snow fence with an effective shade of about 30%. Each shade structure contained a solar radiation meter and a black globe thermometer to measure radiant energy received under the shade material. Additionally, meteorological data were collected as a non-shaded treatment and included temperature, humidity, wind speed, and solar radiation. Data analyses was conducted using a physiological model based on temperature, humidity, solar radiation and wind speed; a second model using black globe temperatures, relative humidity, and wind speed was used as well. Analyses of the data revealed that time spent in the highest stress category was reduced by all shade materials. Moreover, significant differences ( P < 0.05) existed between all shade materials (compared to no-shade) for hourly summaries during peak daylight hours and for `full sun' days.

  13. Cost and Benefit Tradeoffs in Using a Shade Tree for Residential Building Energy Saving

    Directory of Open Access Journals (Sweden)

    Sappinandana Akamphon

    2014-01-01

    Full Text Available Global warming and urban heat islands result in increased cooling energy consumption in buildings. Previous literature shows that planting trees to shade a building can reduce its cooling load. This work proposes a model to determine the cost effectiveness and profitability of planting a shade tree by considering both its potential to reduce cooling energy and its purchase and maintenance cost. A comparison between six selected tree species is used for illustration. Using growth rates, crown sizes, and shading coefficients, cooling energy savings from the tree shades are computed using an industrial-standard building energy simulation program, offset by costs of purchase, planting, and maintenance of these trees. The result shows that most worthwhile tree to plant should have high shading coefficient and moderate crown size to maximize shading while keeping the maintenance costs manageable.

  14. Effects of shading time on quality of matcha and matcha cake

    Directory of Open Access Journals (Sweden)

    LI Hui

    2014-12-01

    Full Text Available Effects of shading time on the quality of Matcha and the Matcha cake.It showed that shading could help the systhesis of nitrogen compounds such as amino acids,caffeine chlorophyll and protein,but couldn′t favor accumulation of tea polyphenol and polysaccharides.The more shading time was,the more chlorophyll content would be,and the more green of Matcha color would be.After Matcha cake was baked,the green color reduced.The colors of Macha cake are greener with longer shading time.Thus,the length of Shading time has obvious effect on the green tea and the tea cake quality,We can adjust the Matcha cake taste,flavor and color by adding Matcha from different shading time.

  15. Cacao Cultivation under Diverse Shade Tree Cover Allows High Carbon Storage and Sequestration without Yield Losses.

    Science.gov (United States)

    Abou Rajab, Yasmin; Leuschner, Christoph; Barus, Henry; Tjoa, Aiyen; Hertel, Dietrich

    2016-01-01

    One of the main drivers of tropical forest loss is their conversion to oil palm, soy or cacao plantations with low biodiversity and greatly reduced carbon storage. Southeast Asian cacao plantations are often established under shade tree cover, but are later converted to non-shaded monocultures to avoid resource competition. We compared three co-occurring cacao cultivation systems (3 replicate stands each) with different shade intensity (non-shaded monoculture, cacao with the legume Gliricidia sepium shade trees, and cacao with several shade tree species) in Sulawesi (Indonesia) with respect to above- and belowground biomass and productivity, and cacao bean yield. Total biomass C stocks (above- and belowground) increased fivefold from the monoculture to the multi-shade tree system (from 11 to 57 Mg ha-1), total net primary production rose twofold (from 9 to 18 Mg C ha-1 yr-1). This increase was associated with a 6fold increase in aboveground biomass, but only a 3.5fold increase in root biomass, indicating a clear shift in C allocation to aboveground tree organs with increasing shade for both cacao and shade trees. Despite a canopy cover increase from 50 to 93%, cacao bean yield remained invariant across the systems (variation: 1.1-1.2 Mg C ha-1 yr-1). The monocultures had a twice as rapid leaf turnover suggesting that shading reduces the exposure of cacao to atmospheric drought, probably resulting in greater leaf longevity. Thus, contrary to general belief, cacao bean yield does not necessarily decrease under shading which seems to reduce physical stress. If planned properly, cacao plantations under a shade tree cover allow combining high yield with benefits for carbon sequestration and storage, production system stability under stress, and higher levels of animal and plant diversity.

  16. Effects of shade on growth, production and quality of coffee (Coffea arabica) in Ethiopia

    OpenAIRE

    Bote, A.D.; Struik, P.C.

    2011-01-01

    The research work was conducted to evaluate the effect of shade on growth and production of coffee plants. To achieve this, growth and productivity of coffee plants growing under shade trees were compared with those of coffee plants growing under direct sun light. Different physiological, environmental and quality parameters were assessed for both treatments. Shade trees protected coffee plants against adverse environmental stresses such as high soil temperatures and low relative humidity. Sh...

  17. Evaluation of self shade matching ability of dental students using visual and instrumental means.

    Science.gov (United States)

    Alsaleh, Samar; Labban, Manal; AlHariri, Morouj; Tashkandi, Esam

    2012-07-01

    The purpose of this study was to evaluate the ability of dental students to match the shade of their own teeth. Fifty female dental students in the College of Dentistry at King Saud University, who had not received any formal dental training in color science or shade matching procedures, were screened for color deficiencies and selected to participate in the study. Each subject and three clinicians selected independently the closest match for the subjects' own right or left sound maxillary central incisors under controlled viewing conditions, using VITA classical shade guide (VITA Zahnfabrik GmbH, Bad Säckingen, Germany). Each examined central incisor and the 16 samples of VITA classical shade guide were measured with the VITA Easy Shade (VES) spectrophotometer to determine the CIELAB color parameters. The color differences (ΔE) between each examined tooth and the 16 samples of the shade guide were calculated. The minimum ΔE values were compared to ΔE values of the shade obtained by VES, subjects and clinicians. The results showed a significant difference in the accuracy of shade selection between the instrumental and visual means. ΔE value of shade selected by clinicians was significantly lower than those selected by the subjects. It was concluded that, spectrophotometric shade analysis was more accurate compared to human shade assessment. A reliable self-perception of the subjects' own tooth color, may aid in the shade matching procedures. It might lead to increased patients' satisfaction at the finalization of the restorative procedures. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Seven indicators variations for multiple PV array configurations under partial shading and faulty PV conditions

    OpenAIRE

    Dhimish, M; Holmes, V.; Mehrdadi, B; Dales, M; Chong, B; Zhang, L.

    2017-01-01

    The goal of this paper is to model, compare and analyze the performance of multiple photovoltaic (PV) array configurations under various partial shading and faulty PV conditions. For this purpose, a multiple PV array configurations including series (S), parallel (P), series-parallel (SP), total-cross-tied (TCT) and bridge-linked (BL) are carried out under several partial shading conditions such as, increase or decrease in the partial shading on a row of PV modules and increase or decrease in ...

  19. Satisfaction of Dental Students, Faculty, and Patients with Tooth Shade-Matching Using a Spectrophotometer.

    Science.gov (United States)

    Ballard, Erin; Metz, Michael J; Harris, Bryan T; Metz, Cynthia J; Chou, Jang-Ching; Morton, Dean; Lin, Wei-Shao

    2017-05-01

    The aims of this study were to evaluate dental students' clinical shade-matching outcomes (from subjective use of shade guide) with an objective electronic shade-matching tool (spectrophotometer); to assess patients', students', and supervising faculty members' satisfaction with the clinical shade-matching outcomes; and to assess clinicians' support for use of the spectrophotometer to improve esthetic outcomes. A total of 103 volunteer groups, each consisting of patient, dental student, and supervising faculty member at the University of Louisville, were recruited to participate in the study in 2015. Using the spectrophotometer, clinical shade-matching outcome (ΔEclinical) and laboratory shade-matching outcome (ΔElaboratory) were calculated. Two five-point survey items were used to assess the groups' satisfaction with the clinical shade-matching outcome and support for an objective electronic shade-matching tool in the student clinic. The results showed that both ΔEclinical (6.5±2.4) and ΔElaboratory (4.3±2.0) were outside the clinical acceptability threshold ΔE values of 2.7, when visual shade-matching method (subjective usage of shade guide) was used to fabricate definitive restorations. Characteristics of the patients, dental students, supervising faculty members, and restorations had minimal to no effect on the ΔEclinical The patients, dental students, and supervising faculty members generally had positive opinions about the clinical shade-matching outcome, despite the increased ΔEclinical observed. Overall, clinical shade-matching outcomes in this school need further improvement, but the patients' positive opinions may indicate the need to revisit the acceptability threshold ΔE value of 2.7 in the academic setting.

  20. Experimental study of the effect of fully shading on the Solar PV module performance

    Science.gov (United States)

    Al-chaderchi, Monadhil; Sopain, K.; Alghoul, M. A.; Salameh, T.

    2017-11-01

    Experimental tests were performed to study the effects of shading for different string inside the photovoltaic (PV) panels, power equipped with different number of diodes from the same manufacturer as of solar panel. The IV curve for all cases were recorded to see how the bypass diodes will reduce the effects of shading .The case for 3 by pass diode show the best performance of solar PV module under shading phenomena.

  1. Resin cement color stability and its influence on the final shade of all-ceramics.

    Science.gov (United States)

    Kilinc, Evren; Antonson, Sibel A; Hardigan, Patrick C; Kesercioglu, Atilla

    2011-07-01

    Adhesive resin cements may go through internal discoloration, which may show-through and affect the appearance of translucent all-ceramic restorations. This in vitro study evaluated the amount of resin cement color change and its effect on the final shade of the all-ceramics. Three different resin cements in both light and dual-cure forms were included in the study (Nexus-2/Kerr; Appeal/Ivoclar Vivadent; Calibra/Dentsply). All resin cements contained veneered (IPS Empress Esthetic, ETC1 shade, 20 mm × 1 mm ingot discs) and uncovered groups (n=10/group), all luted on white backgrounds (acetalpolyoxymethylene/Delrin(®)). Curing was performed according to ISO standards with a calibrated LED curing-light (Flashlite 1401). Samples were stored in 37°C distilled water at dark. Spectrophotometric baseline color measurements (Color Eye 7000A) were performed from the samples' top surfaces at 24h (D65 illuminator). Samples were subjected to 65 h of accelerated ageing (Atlas Ci4000). Further color measurements from the same areas were recorded in CIEL*a*b* coordinates where a ΔE data above 3 was accepted as visible discoloration (OptiviewLite-1.9software). Statistical analysis was performed using a nested random effects model and Tukey's post hoc analysis. Light-cure groups showed better color stability in all three resins but only in Appeal resin cement, the dual-cure group discolored significantly more (pcolor change (ΔE>3) through the ceramic surface on any veneered group. All resin cements showed varying degrees of discoloration after accelerated ageing however their actual color change was partially masked by the ceramic. Dual-cure resin cements may affect aesthetics on restoration margins if directly exposed. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Supraclassical consequence relations: Tolerating rare counterexamples

    CSIR Research Space (South Africa)

    Labuschagne, W

    2013-12-01

    Full Text Available We explore a family of supraclassical consequence relations obtained by varying the criteria according to which counterexamples to classical entailment may be deemed tolerable. This provides a different perspective on the rational consequence...

  3. Ecophysiological and morphological responses to shade and drought in two contrasting ecotypes of Prunus serotina.

    Science.gov (United States)

    Abrams, M D; Kloeppel, B D; Kubiske, M E

    1992-06-01

    Photosynthesis (A), water relations and stomatal reactivity during drought, and leaf morphology were evaluated on 2-year-old, sun- and shade-grown Prunus serotina Ehrh. seedlings of a mesic Pennsylvania seed source and a more xeric Wisconsin source. Wisconsin plants maintained higher A and leaf conductance (g(wv)) than Pennsylvania plants during the entire drought under sun conditions, and during the mid stages of drought under shade conditions. Compared to shade plants, sun plants of both sources exhibited a more rapid decrease in A or % A(max) with decreasing leaf water potential (Psi). Tissue water relations parameters were generally not significantly different between seed sources. However, osmotic potentials were lower in sun than shade plants under well-watered conditions. Following drought, shade plants, but not sun plants, exhibited significant osmotic adjustment. Sun leaves had greater thickness, specific mass, area and stomatal density and lower guard cell length than shade leaves in one or both sources. Wisconsin sun leaves were seemingly more xerophytic with greater thickness, specific mass, and guard cell length than Pennsylvania sun leaves. No source differences in leaf structure were exhibited in shade plants. Stomatal reactivity to sun-shade cycles was similar between ecotypes. However, well-watered and droughted plants differed in stomatal reactivity within and between multiple sun-shade cycles. The observed ecotypic and phenotypic variations in ecophysiology and morphology are consistent with the ability of Prunus serotina to survive in greatly contrasting environments.

  4. Experiment Research on Shading to Improve the Thermal Environment of Tents

    Directory of Open Access Journals (Sweden)

    Liu Jingbo

    2016-01-01

    Full Text Available Different black agricultural shading-nets were erected on two 93 type military cotton tents to improve the thermal environment of tents in this paper. Indoor temperature, RH (relative air humidity and interior wall temperature were tested. The experimental results show that shading-nets a effect on the improvement of thermal environment and 6 needled filters shading-net is better than 3 needled filters shading-net. The conclusion of this paper provides a basis for the improvement of the thermal environment and energy saving design of the tent.

  5. Temperature and water relations for sun and shade leaves of a desert broadleaf, Hyptis emoryi

    Energy Technology Data Exchange (ETDEWEB)

    Smith, W.K.; Nobel, P.S.

    1977-02-01

    The temperature and water relations of sun versus shade leaves of Hyptis emoryi Torr. were evaluated from field measurements made in late summer. Throughout most of the day sun leaves had higher temperatures and higher resistances to water vapor diffusion, but lower transpiration rates and lower stem water potentials, than did shade leaves. Leaf absorptivity to solar irradiation was less for 1.5-cm-long sun leaves (0.44) than for 4.0-cm shade leaves (0.56). For both leaf types the stomatal resistance increased as the water vapor concentration drop from the leaf to the air increased. Energy balance equations were used together with the measured temperature dependence of photosynthesis to predict the effect of variations in leaf absorptivity, length, and resistance on net photosynthesis. The influence of leaf dimorphism on whole plants was determined by calculating daily photosynthesis and transpiration for plants with various percentages of sun and shade leaves. A hypothetical plant with all sun leaves in the sun had about twice the photosynthesis and half the transpiration ratio as did plants with sun leaves in the shade or shade leaves in the sun or shade. Plants with both sun and shade leaves had the highest predicted photosynthesis per unit ground area. The possible adaptive significance of the seasonal variation in sun and shade leaf percentages observed for individual H. emoryi bushes is discussed in terms of water economy and photosynthesis.

  6. Partial Shade Evaluation of Distributed Power Electronics for Photovoltaic Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Deline, C.; Meydbrav, J.; Donovan, M.

    2012-06-01

    Site survey data for several residential installations are provided, showing the extent and frequency of shade throughout the year. This background information is used to design a representative shading test that is conducted on two side-by-side 8-kW photovoltaic (PV) installations. One system is equipped with a standard string inverter, while the other is equipped with microinverters on each solar panel. Partial shade is applied to both systems in a comprehensive range of shading conditions, simulating one of three shade extents. Under light shading conditions, the microinverter system produced the equivalent of 4% annual performance improvement, relative to the string inverter system. Under moderate shading conditions, the microinverter system outperformed the string inverter system by 8%, and under heavy shading the microinverter increased relative performance by 12%. In all three cases, the percentage of performance loss that is recovered by the use of distributed power electronics is 40%-50%. Additionally, it was found that certain shading conditions can lead to additional losses in string inverters due to peak-power tracking errors and voltage limitations.

  7. Soil Bacterial Diversity and Productivity of Coffee - Shade Tree Agro-ecosystems

    Directory of Open Access Journals (Sweden)

    Rusdi Evizal

    2012-05-01

    Full Text Available Coffee productions should have environmental values such as providing high soil microbial diversity while producinghigh yield. To examine that purposes, two experimental plots were constucted at benchmark site of Conservationand Sustainable Management of Below-Ground Biodiversity (CSM-BGBD, in Sumberjaya Subdistrict, WestLampung, Indonesia, during 2007-2010. Types of coffee agro-ecosystem to be examined were Coffea canephorawith shade trees of Gliricidia sepium, Erythrina sububrams, Michelia champaca, and no shade. Two plots wereconstructed at 5-years-coffee and 15-years-coffee. Diversity of soil bacteria was determined based on DNA fingerprinting of total soil bacteria using Ribosomal Intergenic Spacer Analysis (RISA method. The results showed that:(1 For mature coffee (15 years old, shade-grown coffee agro-ecosystems had higher soil bacterial diversity thanthose of no shade coffee agro-ecosystem, (2 Shaded coffee agro-ecosystems were able to conserve soil bacterialdiversity better than no-shade coffee agro-ecosystem. Soil organic C and total litter biomass had positive effect onsoil bacterial diversity, (3 Types of agro-ecosystem significantly affected the bean yield of 15 years coffee. Coffeeagro-ecosystems shaded by legume trees had higher yield than those of non-legume shade and no shade coffeeagro-ecosystem, (4 Shannon-Weaver indices of soil bacterial diversity together with weed biomass and N contentof coffee leaf had positive effect on coffee bean yield.

  8. Esthetic restorative material shade changes due to photopolymerization.

    Science.gov (United States)

    Watanabe, Hidehiko; Covey, David

    2008-05-01

    This study sought to measure color values (before and after photopolymerization) and variations of A1 shade polymeric dental restorative materials. The L*a*b* values of polymeric dental restorative material disks were measured by a spectrophotometer with the specular component excluded (SCE) geometry under D65 illumination over a standardized white background before and after photopolymerization. Color differences (DeltaE*ab) due to polymerization were calculated using the CIE Lab color-difference formula. DeltaE*ab indicates differences between two colors in the L*a*b* color space. In this system, L*, a*, and b* indicate lightness, red-green, and yellow-blue, respectively. Color differences (DeltaE*ab) were calculated by the equation DeltaE*ab = [(DeltaL*)2 + (Deltaa*)2 + (Deltab*)2]1/2. Eight resin composites, three flowable resin composites (FRCs), and two resin-modified glass ionomers (RMGIs) were utilized; L*a*b* and DeltaE*ab values of the test groups were analyzed using ANOVA and Newman-Keuls multiple comparison tests. DeltaE*ab values before and after photopolymerization ranged from 3.01-17.76. All RMGI and two FRC materials displayed greater color changes than the resin composites (p < 0.05). Photopolymerization produced measurable increases and decreases in lightness. Yellow-blue (b*) values decreased in all test groups after polymerization, while most red-green (a*) values increased. Color differences between polymerized A1 shade materials ranged from 0.76-25.41 DeltaE*ab. The color difference between the test materials and a widely used tooth shade guide (the Vita Lumin) was averaged at 12.66 DeltaE*ab.

  9. Performance of a daylight-redirecting glass-shading system

    DEFF Research Database (Denmark)

    Appelfeld, David; Svendsen, Svend

    2013-01-01

    to the original system. The visual comfort was evaluated by glare analysis and the redirected daylight did not cause an additional discomfort glare. The higher utilization of daylight can save 20% of the lighting energy. The thermal insulation of the fenestration was maintained, with slightly increased solar......This paper evaluates the daylighting performance of a prototype external dynamic shading and daylight-redirecting system, and the main focus is on the performance simulation. The demonstration project was carried out on a building with an open-plan office. Part of the original façade was replaced...

  10. Shades of irony in the anti-language of Amos

    OpenAIRE

    William Domeris

    2016-01-01

    The rhetoric of Amos includes a wonderful mixture of humour and threat, sarcasm and irony, hyperbole and prediction. Holding the fabric of this conversation together is Amos’s place within the prophetic minority – the Yahweh-only party (his anti-society). Making use of sociolinguistics, and particularly the idea of anti-language, I take a closer look at Amos, including his use of overlexicalisation, insider-humour and all the shades of irony one might expect. Typically of a member of an anti-...

  11. Repeated Thermal Stress, Shading, and Directional Selection in the Florida Reef Tract

    Directory of Open Access Journals (Sweden)

    Robert van Woesik

    2017-06-01

    Full Text Available Over the last three decades reef corals have been subjected to an unprecedented frequency and intensity of thermal-stress events, which have led to extensive coral bleaching, disease, and mortality. Over the next century, the climate is predicted to drive sea-surface temperatures to even higher levels, consequently increasing the risk of mass bleaching and disease outbreaks. Yet, there is considerable temporal and spatial variation in coral bleaching and in disease prevalence. Using data collected from 2,398 sites along the Florida reef tract from 2005 to 2015, this study examined the temporal and spatial patterns of coral bleaching and disease in relation to coral-colony size, depth, temperature, and chlorophyll-a concentrations. The results show that coral bleaching was most prevalent during the warmest years in 2014 and 2015, and disease was also most prevalent in 2010, 2014, and 2015. Although the majority of the corals surveyed were found in habitats with low chlorophyll-a concentrations, and high irradiance, these same habitats showed the highest prevalence of coral bleaching and disease outbreaks during thermal-stress events. These results suggest that directional selection in a warming ocean may favor corals able to tolerate inshore, shaded environments with high turbidity and productivity.

  12. Smoothly Varying Bright Blazars

    Science.gov (United States)

    Van Alfen, Nicholas; Hindman, Lauren; Moody, Joseph Ward; Biancardi, Rochelle; Whipple, Parkes; Gaunt, Caleb

    2018-01-01

    It is becoming increasingly apparent that blazar light can vary sinusoidally with periods of hundreds of days to tens of years. Such behavior is expected of, among other things, jets coming from binary black holes. To look for general variability in lesser-known blazars and AGN, in 2015-2016 we monitored 182 objects with Johnson V-band magnitudes reported as being < 16. In all, this campaign generated 22,000 frames from 2,000 unique pointings. We find that approximately one dozen of these objects show evidence of smooth variability consistent with sinusoidal periods. We report on the entire survey sample, highlighting those that show sinusoidal variations.

  13. Lightness, chroma, and hue distributions of a shade guide as measured by a spectroradiometer.

    Science.gov (United States)

    Lee, Yong-Keun; Yu, Bin; Lim, Ho-Nam

    2010-09-01

    The color attributes of commercially available shade guides have been measured by spectrophotometers (SP), which are designed to measure flat surfaces. However, there is limited information on the color distribution of shade guides as measured by spectroradiometers (SR), which are capable of measuring the color of curved surfaces. The purpose of this study was to determine the distributions of lightness (CIE L*) and chroma (C*(ab)) step intervals between adjacent shade tabs of a shade guide based on the lightness, chroma, and hue attributes measured by an SR. Lightness, chroma, hue angle, and CIE a* and b* values of the shade tabs (n=26) from a shade guide (Vitapan 3D-Master) were measured by an SR under daylight conditions. The distributions of the ratios in lightness and chroma of each tab compared with the lowest lightness tab or the lowest chroma tab were determined. The values for each color parameter were analyzed by a 3-way ANOVA with the factors of lightness, chroma, and hue designations of the shade tabs (alpha=.05). The chroma and CIE a* and b* values were influenced by the lightness, chroma, and hue designations of the shade tabs (P<.001); however, the lightness and hue angle were influenced by the lightness and hue designations, but not by the chroma designation. Distributions for the CIE a* and b* values, in each lightness group, corresponded with the chroma designation. However, the intervals in the lightness and chroma scales between adjacent tabs were not uniform. The intervals in the color parameters between adjacent shade tabs were not uniform based on SR measurements. Therefore, a shade guide in which shade tabs are more equally spaced by the color attributes, based on the values as measured by an SR along with observers' responses with respect to the equality of the intervals, should be devised. Copyright © 2010 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  14. [Comparison of shade matching accuracy of tabs of shadeguide and tabs out of shadeguide].

    Science.gov (United States)

    Xu, Ming-Ming; Xu, Tong-Kai; Liu, Feng; Ren, Shu-Xin; Feng, Hai-Lan

    2009-07-01

    To compare the shade matching accuracy between tabs of shade guide and tabs out of shade guide by prosthodontists. Sixty-two graduate students who had 1 to 5 years clinical experience without color blindness were included in this study. Twenty-nine tabs from Vita 3D-Master shadeguide and 7 tabs out of Vita 3D-Master shade guide but from Vita Bleachedguide 3D-Master were taken as the targets of shade matching and observed under the standard light. Subjects' shade matching accuracy on tabs of shadeguide and tabs out of shadeguide was recorded. Frequency of right match was analyzed using Monte Carlo exact probability-test. Wilcoxin test was used to analyze the difference between each group on ranked data of value, chroma and hue. The shade matching accuracy of tabs of shade guide [45.9% (199/434)] was significantly higher than that of tabs out of shade guide [9.0% (39/434)]. There was significant difference between the two kinds of tabs of ranked data of value [0.2 (0.1 - 0.3), 0.4 (0.4 - 0.5)] and chroma [0.2 (0.1 - 0.4), 0.5 (0.4 - 0.6), P < 0.01, but there was no significant difference in hue data [0.3 (0.1 - 0.4), 0.3 (0.1 - 0.4)]. The shade matching ability of prosthodontists on tabs out of shade guide is lower than that on tabs of shadeguide. To fulfill clinical need, more training is necessary.

  15. Effect of Shading on some Important Physiological Traits in Lentil Crop

    Directory of Open Access Journals (Sweden)

    F. Darabi

    2015-05-01

    Full Text Available Light is one of the growth-reducing factors in mixed cropping and agroforestry systems. Therefore, an experimental field was conducted to justiffy the effect of light intensity on two lentil cultivars. It was performed in a factorial experiment based on randomized complete block design with three replications at Agricultural Research Station of Ilam University during 2012-2013 cropping season. The factors under study consisted of shading in four levels (0 shading, 25, 50, 75 and 100% of shadings and two cultivars lentil (Lens culinaris Medic (Ziba and ILL4400. Results showed that physiologic traits were significantly affected by cultivar × shading intraction. Ziba cultivar had the highest chlorophyll a and b content in 100% shading. Carotenoid content, relative water content and leaf area index also increased with increasing in shading. The highest and lowest carotenoid and relative water contents were observed in 100% shading × ILL4400 cultivar and control treatment × Ziba cultiva, respectively. The highest leaf specific weight observed in control treatment × Ziba cultivar and decreased with increasing shading. Grain yield decreased with increasing shading. The highest and lowest mean grain yield, 2522 kg.ha-1 and 1137 kg.ha-1, were observed in control treatment × Ziba cultivar and 100% shading and ILL4400 cultivar, respectively. Based on the results of this study, Ziba cultivar had the highest leaf area index, relative water content and chlorophyll a in higher shading treatments; hence, it can perform better than ILL4400 in mixed cropping and agroforestry systems where the light is limited factor.

  16. Appearance Differences Between Lots and Brands of Similar Shade Designations of Dental Composite Resins.

    Science.gov (United States)

    Carney, Melody N; Johnston, William M

    2017-04-01

    The purposes of this study were to investigate differences in two inherent appearance characteristics between lots of an enamel dental composite resin of the same shade and brand, and to further compare these differences to those of similar shade designation of a different brand of dental composite resins. Appearance analyses proceeded for three different lots of shades A1, B2, and D3 manufactured by one company and for one lot of shade EA1 manufactured by another. Samples were measured on black, white, and gray backings using spectroradiometry. Kubelka-Munk theory was used to determine reflectivity of each lot studied. CIELAB values and color differences between shades and lots were analyzed. Translucency indicators were compared between lots over thicknesses from 0.5 to 3.0 mm. Differences in inherent color between some lots of same shade designations within a brand were found to be above the acceptability threshold. Color difference between an enamel composite resin of shade A1 and a composite resin of shade EA1 was also above the acceptability threshold. Statistically significant differences in the translucency were found between some lots of one shade over the entire range of thicknesses studied. Appearance analyses indicate substantial variation between lots of same shade designations as well as between brands of similar shade designations. Optical principles applied to important clinical appearance attributes are described which characterize inherent appearance attributes and provide aid in the appearance matching process for dental composite resins used in restorative and operative dental procedures. (J Esthet Restor Dent 29:E6-E14, 2017). © 2016 Wiley Periodicals, Inc.

  17. Evaluation of Cellular Shades in the PNNL Lab Homes

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Joseph M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sullivan, Greg [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cort, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Metzger, Cheryn E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Merzouk, Massine [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-11-01

    This report examines the energy performance of cellular shade window coverings in a matched pair of all-electric, factory-built “Lab Homes” located on the Pacific Northwest National Laboratory (PNNL) campus in Richland, Washington. The 1500-square-foot homes were identical in construction and baseline performance, which allowed any difference in energy and thermal performance between the baseline home and the experimental home to be attributed to the retrofit technology installed in the experimental home. To assess the performance of high efficiency window attachments in a residential retrofit application, the building shell air leakage, energy use, and interior temperatures of each home were compared during the 2015 -2016 winter heating and summer cooling seasons. Hunter Douglas Duette® Architella® Trielle™ opaque honeycomb “cellular” shades were installed over double-pane clear-glass, aluminum-frame primary windows in the experimental home and were compared to identical primary windows with no window coverings and with standard typical white vinyl horizontal blind window coverings in the baseline home.

  18. Modeling Hydrological Services in Shade Grown Coffee Systems: Case Study of the Pico Duarte Region of the Dominican Republic

    Science.gov (United States)

    Erickson, J. D.; Gross, L.; Agosto Filion, N.; Bagstad, K.; Voigt, B. G.; Johnson, G.

    2010-12-01

    The modification of hydrologic systems in coffee-dominated landscapes varies widely according to the degree of shade trees incorporated in coffee farms. Compared to mono-cropping systems, shade coffee can produce both on- and off-farm benefits in the form of soil retention, moderation of sediment transport, and lower hydropower generating costs. The Pico Duarte Coffee Region and surrounding Madres de Las Aguas (Mother of Waters) Conservation Area in the Dominican Republic is emblematic of the challenges and opportunities of ecosystem service management in coffee landscapes. Shade coffee poly-cultures in the region play an essential role in ensuring ecosystem function to conserve water resources, as well as provide habitat for birds, sequester carbon, and provide consumptive resources to households. To model the provision, use, and flow of ecosystem services from coffee farms in the region, an application of the Artificial Intelligence for Ecosystem Services (ARIES) model was developed with particular focus on sediment regulation. ARIES incorporates an array of techniques from data mining, image analysis, neural networks, Bayesian statistics, information theory, and expert systems to model the production, delivery, and demand for ecosystem services. Geospatial data on slope, soils, and vegetation cover is combined with on-farm data collection of coffee production, tree diversity, and intercropping of household food. Given hydropower production and river recreation in the region, the management of sedimentation through on-farm practices has substantial, currently uncompensated value that has received recent attention as the foundation for a payment for ecosystem services system. Scenario analysis of the implications of agro-forestry management choices on farmer livelihoods and the multiple beneficiaries of farm-provided hydrological services provide a foundation for ongoing discussions in the region between local, national, and international interests.

  19. The production of Physalis spp. seedlings grown under different-colored shade nets

    Directory of Open Access Journals (Sweden)

    Daniel Fernandes da Silva

    2016-04-01

    Full Text Available The objective of this study was to evaluate the production of seedlings of Physalis L. species under different-colored shade nets. Four shade nets individually stained white, blue, red and black, all with 50% shading, were used in this study, and an additional  treatment (control was used in which seedlings were grown in full sun. The study examined four species of Physalis, namely, P. peruviana, P. pubescens, P. minima and P. ixocarpa. The experiment followed a randomized block design with three blocks and 25 seeds per plot. The species were sown in styrofoam trays. Germination was monitored daily to calculate the Emergency Velocity Index (EVI and stabilize the overall percentage of emergence. Height, stem diameter, number of leaves, leaf area index and dry mass of seedlings were assessed at 50 days after sowing. The study found that these species react differently to changes in the light spectrum. Seedlings of P. peruviana should be grown under a white or red shade net; of P. pubescens under a white or black shade net; of P. minima under a white, red or black shade net; and of P. ixocarpa under a white shade net. For all species, 50% shade should be used.

  20. Effects of shade on growth, production and quality of coffee (Coffea arabica) in Ethiopia

    NARCIS (Netherlands)

    Bote, A.D.; Struik, P.C.

    2011-01-01

    The research work was conducted to evaluate the effect of shade on growth and production of coffee plants. To achieve this, growth and productivity of coffee plants growing under shade trees were compared with those of coffee plants growing under direct sun light. Different physiological,

  1. Comparison between visual and instrumental methods for natural tooth shade matching.

    Science.gov (United States)

    Pimental, Welson; Tiossi, Rodrigo

    2014-01-01

    Tooth shade matching in daily clinical practice is still a cause of discomfort for many professionals due to the subjectivity of the process and the need for advanced training; this discomfort may lead to unsatisfactory results for the clinician and the patient. Instrumental methods were developed to simplify daily color matching procedures and to provide better esthetic outcomes. This study compared the accuracy of shade matching by both visual and instrumental methods to determine whether the instrumental method would significantly improve the process. Visual shade matching was performed by 4 dentists using a classic shade guide; instrumental shade matching was performed with a spectrophotometer by a previously calibrated examiner. Shade matching was conducted in a dental clinic under controlled illumination on the middle third of the right central incisor tooth of 30 subjects. Data were analyzed by Cohen's Kappa inter-rater agreement and by the equality of 2 proportions test (α = 0.05). Results showed statistically significant differences between the groups (76.7 ± 11.1% and 32.4% ± 7.8% for the instrumental and visual methods, respectively). Shade matching by clinicians using the instrumental method presented more agreement, and was more effective than shade matching by clinicians using the visual method.

  2. The effects of shade and shearing date on the production of Merino ...

    African Journals Online (AJOL)

    Unknown

    South African Society of Animal Science. The South African Journal of Animal Science is available online at http://www.sasas.co.za/Sajas.html. 164 ..... Staple strength. (N/ktex). Overall mean. Shade treatment. Control. Shade provided. Shearing treatment. Pre-joining. Pre-lambing. Reproduction status. Barren. Lambed and ...

  3. Perceived color shift of a shade guide according to the change of illuminant.

    Science.gov (United States)

    Lee, Yong-Keun; Yu, Bin; Lim, Jin Ik; Lim, Ho-Nam

    2011-02-01

    The perceived color of shade guide tabs is influenced by different spectral compositions of different light sources, and this can influence color matching. The purpose of this study was to determine the amount of perceived shift in color and color coordinates of a shade guide using 3 different light sources: CIE standard illuminant D65 (daylight), A (incandescent lamp), and F9 (fluorescent lamp). CIE color coordinates L*, a*, b*, chroma, and the spectral reflectance of shade tabs in a shade guide (Vitapan 3D-Master) were measured by a spectroradiometer under D65, A, and F9 simulators. Perceived color and color coordinate shifts due to the change of illuminant were determined. The influence of the type of light and shade designation of the 26 tabs on the color coordinates was analyzed by a 2-way ANOVA; correlations in the color coordinates between each corresponding pair under the 3 illuminants were determined (α=.05). All of the color coordinates were influenced by the type of illuminant and shade designation of the shade tabs (P2.6). Lightness decreased and chroma increased when the illuminant was changed from the D65 simulator to the A or F9 simulators. Perceptible shifts in the color of shade guide tabs under different ambient lighting conditions were confirmed by a spectroradiometer; these color shifts were influenced by the type of illuminant used. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  4. Non-linear effects of drought under shade: reconciling physiological and ecological models in plant communities

    NARCIS (Netherlands)

    Holmgren, M.; Gomez-Aparicio, L.; Quero, J.L.; Valladares, F.

    2012-01-01

    The combined effects of shade and drought on plant performance and the implications for species interactions are highly debated in plant ecology. Empirical evidence for positive and negative effects of shade on the performance of plants under dry conditions supports two contrasting theoretical

  5. [Research on the designing method of a special shade guide for tooth whitening].

    Science.gov (United States)

    Xu, Yingxin

    2015-10-01

    To investigate a method of designing an accurate and scientific shade guide, especially used for judging the effect of tooth whitening, by analyzing the colorimetric values of discolored teeth statistically. One hundred thirty-six pictures of patients who had been receiving the Beyond cold light whitening treatment from February 2009 to July 2014 were analyzed, including 25 tetracycline teeth, 61 mottled-enamel teeth, and 50 yellow teeth. The colorimetric values of discolored teeth were measured. The L* values of shade tabs were calculated by hierarchical clustering of those of discolored teeth. The a* and b* values of shade tabs were the mean of those observed for discolored teeth. Accordingly, different shade guides were designed for each type of discolored teeth, and the effects were evaluated. A statistically significant difference in colorimetric values was found among the three types of discolored teeth. Compared with the Vitapan Classical shade guide, the shade guides designed through the present method were more scientific and accurate in judging the effect of tooth whitening. Moreover, the arrangement of shade tabs was more logical, and the color difference between shade tabs and discolored teeth was smaller. The proposed designing method is theoretically feasible, although its clinical effect has yet to be proven.

  6. Effects of shading on morphology, physiology and grain yield of winter wheat

    DEFF Research Database (Denmark)

    Li, Huawei; Jiang, Dong; Wollenweber, Bernd

    2010-01-01

    the shading treatments applied, leaf area index, length of the peduncle internode, area of the upper leaves and content of pigments increased, which favoured efficient light capture. Shading modified light quality in the canopy as indicated by increases of diffuse- and blue light fractions and a reduction...

  7. The art of being flexible: how to escape from shade, salt, and drought.

    NARCIS (Netherlands)

    Pierik, R.; Testerink, C.

    2014-01-01

    Environmental stresses, such as shading of the shoot, drought, and soil salinity, threaten plant growth, yield, and survival. Plants can alleviate the impact of these stresses through various modes of phenotypic plasticity, such as shade avoidance and halotropism. Here, we review the current state

  8. Impact of shade and cocoa plant densities on soil organic carbon ...

    African Journals Online (AJOL)

    The results suggest that cocoa planted at low plant density under shade stores more carbon per unit area of soil than an equivalent area of cocoa planted at high density without shade. It is concluded that cocoa farming could be an effective means to mitigate carbon dioxide emissions in cocoa growing countries. Key words: ...

  9. Effect of shade on various parameters of Friesian cows in a ...

    African Journals Online (AJOL)

    Shade cows spent more time (P < 0.05) feeding during the day than no-shade cows, while there was no ... stress. A knowledge of the behaviour and daily activities of dairy cows may be useful mainly in two ways, namely: (i) a change in behaviour may indicate some ..... Eating habits of dairy cows under drylot conditions.

  10. The adaptive evolution of plasticity: phytochrome-mediated shade avoidance responses.

    Science.gov (United States)

    Schmitt, Johanna; Stinchcombe, John R; Heschel, M Shane; Huber, Heidrun

    2003-07-01

    Many plants display a characteristic suite of developmental "shade avoidance" responses, such as stem elongation and accelerated reproduction, to the low ratio of red to far-red wavelengths (R:FR) reflected or transmitted from green vegetation. This R:FR cue of crowding and vegetation shade is perceived by the phytochrome family of photoreceptors. Phytochrome-mediated responses provide an ideal system for investigating the adaptive evolution of phenotypic plasticity in natural environments. The molecular and developmental mechanisms underlying shade avoidance responses are well studied, and testable ecological hypotheses exist for their adaptive significance. Experimental manipulation of phenotypes demonstrates that shade avoidance responses may be adaptive, resulting in phenotypes with high relative fitness in the environments that induce those phenotypes. The adaptive value of shade avoidance depends upon the competitive environment, resource availability, and the reliability of the R:FR cue for predicting the selective environment experienced by an induced phenotype. Comparative studies and a reciprocal transplant experiment with Impatiens capensis provide evidence of adaptive divergence in shade avoidance responses between woodland and clearing habitats, which may result from population differences in the frequency of selection on shade avoidance traits, as well as differences in the reliability of the R:FR cue. Recent rapid progress in elucidating phytochrome signaling pathways in the genetic model Arabidopsis thaliana and other species now provides the opportunity for studying how selection on shade avoidance traits in natural environments acts upon the molecular mechanisms underlying natural phenotypic variation.

  11. The influence of porcelain layer thickness on the final shade of ceramic restorations.

    Science.gov (United States)

    Dozić, Alma; Kleverlaan, Cornelis Johannes; Meegdes, Marcel; van der Zel, Jef; Feilzer, Albert Joseph

    2003-12-01

    Ceramic restorations should be made of porcelain layers of different opacity, shade, and thickness in order to provide a natural appearance. By means of CAD/CAM layering technology such as CICERO, it is feasible to produce all-ceramic crowns with porcelain layers of predetermined thickness. However, it is not yet known whether changes in thickness of these porcelain layers within the clinically available space can perceivably influence the overall shade of the restoration. The purpose of this study was to determine, quantitatively, the effect of different thickness ratios of opaque porcelain (OP) and translucent porcelain (TP) layers on the overall shade of all-ceramic specimens. The CIELAB values of 5 assembled specimens, each consisting of 2 or 3 discs (CORE 0.70 mm/OP--0, 0.25, 0.50, 0.75, or 1.00 mm/TP 1.00, 0.75, 0.50, 0.25, or 0 mm) were determined with a spectrophotometer for the Vita shades A1, A2, and A3. Distilled water was used to attain optical contact between the layers. Black or white backgrounds were used to assess the influence of the background on the final shade. Color differences (DeltaE) between layered specimens were determined. Correlation between the thickness ratio and the L*, a*, and b* values was calculated by 2-tailed Spearman correlation analysis. The results indicated that small changes in OP/TP thickness ratio can perceivably influence the final shade of the layered specimens (DeltaE>1). Redness a* and yellowness b* increased with the thickness of OP for all shades. Redness a* (P<.01 for all shades) correlated more strongly with thickness than yellowness b* (P<.01 for A1 and A3; P<.05 for A2). The lightness (L*) was shade dependent. The correlation (r) between OP/TP thickness and L* was 0.975 (P<.01) for shade A1, 0.700 (not statistically significant) for shade A2, and 0.900 (P<.05) for shade A3. Small changes in thickness and shade of opaque and translucent porcelain layers can influence the final shade of the layered porcelain

  12. USGS Small-scale Dataset - Topographic and Bathymetric Shaded Relief of North America 200509 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Topographic and Bathymetric Shaded Relief of North America map layer shows depth and elevation ranges using colors, with relief enhanced by shading. The image...

  13. Apple tree growth, net photosynthesis, dark respiration, and specific leaf weight as affected by continuous and intermittent shade

    Energy Technology Data Exchange (ETDEWEB)

    Barden, J.A.

    1977-07-01

    The effects of 80% shade from saran cloth and slats were very similar on young Delicious apple (Malus domestica Borkh.) trees. Shoot-length increase was suppressed about 10% by shade but leaf area was unaffected. Dry weight increase for shaded trees was about 50% of that for trees in full sun. Sun leaves required about 43.1 klx for light saturation and shade leaves needed only about 19.4 klx. Net photosynthesis (Pn) of shade leaves was about 70% of that of sun leaves at light saturation. Dark respiration (Rd) rates were also higher in sun- than shade-leaves. Specific leaf weight (SLW) of leaves near full expansion at the start of the experiment increased 15% under shade whereas sun-leaf SLW increased 40% during the experiment. For leaves unfolding under the differential light treatments, SLW of shade leaves averaged only 55% of sun leaves. 4 figures, 3 tables.

  14. USGS Small-scale Dataset - 100-Meter Resolution Grayscale Shaded Relief of the Conterminous United States 201304 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Grayscale Shaded Relief of the Conterminous United States map layer is a 100-meter resolution grayscale shaded relief image of the United States, in an Albers...

  15. USGS Small-scale Dataset - 100-Meter Resolution Color Shaded Relief of the Conterminous United States 201304 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Color Shaded Relief of the Conterminous United States map layer is a 100-meter resolution color-sliced elevation image of the United States, with relief shading...

  16. Shading decreases the abundance of the herbivorous California horn snail, Cerithidea californica

    Science.gov (United States)

    Lorda, Julio; Lafferty, Kevin D.

    2012-01-01

    Most of the intertidal zone in estuaries of California, USA and Baja California, Mexico is covered with vascular vegetation. Shading by these vascular plants influences abiotic and biotic processes that shape benthic community assemblages. We present data on the effects of shading on the California horn snail, Cerithidea californica. This species is important because it is the most common benthic macrofaunal species in these systems and acts as an obligate intermediate host of several species of rematode parasites that infect several other species. Using observational and experimental studies, we found a negative effect of shade on the distribution and abundance of the California horn snail. We hypothesized that shading reduces the abundance of the epipelic diatoms that the snails feeds on, causing snails to leave haded areas. We observed a negative relationship between vascular plant cover, sub-canopy light levels, and snail density in Mugu Lagoon. Then we experimentally manipulated light regimes, by clipping vegetation and adding shade structures, and found higher snail densities at higher light levels. In Goleta Slough, we isolated the effect of shade from vegetation by documenting a negative relationship between the shade created by two bridges and diatom and snail densities. We also found that snails moved the greatest distances over shaded channel banks compared to unshaded channel banks. Further, we documented the effect of water depth and channel bank orientation on shading in this system. An additional effect of shading is the reduction of temperature, providing an alternative explanation for some of our results. These results broaden our knowledge of how variation in the light environment influences the ecology of estuarine ecosystems.

  17. Single color attribute index for shade conformity judgment of dental resin composites

    Directory of Open Access Journals (Sweden)

    Yong-Keun Lee

    2015-01-01

    Full Text Available Introduction: Commercial dental resin composites under the same shade designations show color discrepancies by brand. Moreover, three Commission Internationale de l′Eclairage (CIE color coordinates show significant variations by measurement method; therefore, direct comparisons of the color coordinates based on different methods are meaningless. This study aimed to assess a hypothesis that a new color attribute index (CAI, which could reduce the color coordinate variations by measurement method, was applicable for the shade conformity judgment of dental resin composites. The Hypothesis: CAI is applicable in the shade conformity judgment of commercial dental resin composites. Using the CIE color coordinates of shade guide tabs and resin composites, combined color indices such as Wa = CIE aFNx01 × DEFNx01 ab /C ab FNx01 and Wb = CIE bFNx01 × DEFNx01 ab /C ab FNx01 were defined, in which DEFNx01 ab was the color difference with a standard white tile. Ratio of Wa/Wb to that of an arbitrary reference shade (A2 in the same brand and measurement was defined as the CAI. The CAI values were significantly different by the shade designation and showed a logical trend by the shade designation number. The CAI of commercial resin composites and the keyed shade guide tabs showed overlaps. Evaluation of the Hypothesis: The CAI might be used to judge the shade conformity of resin composites using the values based on different measurement methods. The application of the CAI, instead of conventional three-color coordinates, could efficiently simplify the shade conformity judgment of commercial resin composites. Although the hypothesis of the present study was partially confirmed, further studies for the practical application of this index are highly recommended.

  18. Assessment of color parameters of composite resin shade guides using digital imaging versus colorimeter.

    Science.gov (United States)

    Yamanel, Kivanc; Caglar, Alper; Özcan, Mutlu; Gulsah, Kamran; Bagis, Bora

    2010-12-01

    This study evaluated the color parameters of resin composite shade guides determined using a colorimeter and digital imaging method. Four composite shade guides, namely: two nanohybrid (Grandio [Voco GmbH, Cuxhaven, Germany]; Premise [KerrHawe SA, Bioggio, Switzerland]) and two hybrid (Charisma [Heraeus Kulzer, GmbH & Co. KG, Hanau, Germany]; Filtek Z250 [3M ESPE, Seefeld, Germany]) were evaluated. Ten shade tabs were selected (A1, A2, A3, A3,5, A4, B1, B2, B3, C2, C3) from each shade guide. CIE Lab values were obtained using digital imaging and a colorimeter (ShadeEye NCC Dental Chroma Meter, Shofu Inc., Kyoto, Japan). The data were analyzed using two-way analysis of variance and Bonferroni post hoc test. Overall, the mean ΔE values from different composite pairs demonstrated statistically significant differences when evaluated with the colorimeter (p 6.8). For all shade pairs evaluated, the most significant shade mismatches were obtained between Grandio-Filtek Z250 (p = 0.021) and Filtek Z250-Premise (p = 0.01) regarding ΔE mean values, whereas the best shade match was between Grandio-Charisma (p = 0.255) regardless of the measurement method. The best color match (mean ΔE values) was recorded for A1, A2, and A3 shade pairs in both methods. When proper object-camera distance, digital camera settings, and suitable illumination conditions are provided, digital imaging method could be used in the assessment of color parameters. Interchanging use of shade guides from different composite systems should be avoided during color selection. © 2010, COPYRIGHT THE AUTHORS. JOURNAL COMPILATION © 2010, WILEY PERIODICALS, INC.

  19. Developing a custom dental porcelain shade system for computer color matching.

    Science.gov (United States)

    Ishikawa-Nagai, Shigemi; Wang, Jian; Seliger, Alison; Lin, Jin; Da Silva, John

    2013-08-01

    This study aims to update the computer color matching method by generating a new ceramic shade system that covers the entire spectrum of natural tooth color and has an efficient design. First, the color map of 176 maxillary natural incisors and two commercially available and commonly used shade guide systems (Vitapan classic and 3D master) were drawn. Then, 15 shades of layered disks (NW-0: neutral white-0, A1, A2, A3, A4, B1, B4, C4, and D4, and six modifiers; white, pink, grey, blue, cervical-1 and cervical-2, Cerabien ZR) were plotted on the tooth color distribution map. Ultimately, 12 target shades were selected around the perimeter of the natural tooth color space, and nine different shades were selected within the cluster. By trial and error informed by known formulations published previously, the formulations of Cerabien ZR porcelain powders necessary to achieve these 21 target shades in thickness of 1.0mm layered on zirconia substrate were then determined and ceramic disks were fabricated. Color distribution L*-C* and a*-b* maps showed that new 21 shade system covers a slightly broader range than the natural tooth distribution, and its distribution is larger than the 3D Master shade's range. In the present study, a 21 custom dental porcelain shade system was developed with a 1.0mm porcelain thickness overlying a zirconia substrate, which can be incorporated into the computer color matching system. This new shade system has homogeneity with 3D Master, and has a slightly wider color distribution than that of natural teeth. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. varying elastic parameters distributions

    KAUST Repository

    Moussawi, Ali

    2014-12-01

    The experimental identication of mechanical properties is crucial in mechanics for understanding material behavior and for the development of numerical models. Classical identi cation procedures employ standard shaped specimens, assume that the mechanical elds in the object are homogeneous, and recover global properties. Thus, multiple tests are required for full characterization of a heterogeneous object, leading to a time consuming and costly process. The development of non-contact, full- eld measurement techniques from which complex kinematic elds can be recorded has opened the door to a new way of thinking. From the identi cation point of view, suitable methods can be used to process these complex kinematic elds in order to recover multiple spatially varying parameters through one test or a few tests. The requirement is the development of identi cation techniques that can process these complex experimental data. This thesis introduces a novel identi cation technique called the constitutive compatibility method. The key idea is to de ne stresses as compatible with the observed kinematic eld through the chosen class of constitutive equation, making possible the uncoupling of the identi cation of stress from the identi cation of the material parameters. This uncoupling leads to parametrized solutions in cases where 5 the solution is non-unique (due to unknown traction boundary conditions) as demonstrated on 2D numerical examples. First the theory is outlined and the method is demonstrated in 2D applications. Second, the method is implemented within a domain decomposition framework in order to reduce the cost for processing very large problems. Finally, it is extended to 3D numerical examples. Promising results are shown for 2D and 3D problems.

  1. Genomic regions associated with freezing tolerance and snow mold tolerance in winter wheat

    Science.gov (United States)

    Crops grown through the winter are subject to selective pressures that vary with each year’s unique conditions, necessitating tolerance of numerous stress factors. The objective of this study was to identify molecular markers in winter wheat (Triticum aestivum L. em Thell) associated with tolerance...

  2. Quantification of the amount of light passing through zirconia: the effect of material shade, thickness, and curing conditions.

    Science.gov (United States)

    Ilie, Nicoleta; Stawarczyk, Bogna

    2014-06-01

    This study aimed to evaluate the amount of light (360-540 nm) passing through shaded zirconia with respect to material thickness, exposure distance, and different curing modes. The specimens were divided into groups according to thickness as follows: 0.5, 1, 1.5, 2, 2.5, and 3 mm. Thirty-five zirconia and seven glass-ceramic (control group) specimens were fabricated for each group (N=252). Zirconia was divided into five subgroups (n=7) and stained to the following shades: CL1, CL2, CL3, and CL4. One zirconia group remained unstained (CL0). Irradiance passing through the different specimens was measured using a violet-blue LED curing unit in three curing modes (Xtra-power, high-power, and standard-power mode) with a fibre-optic USB4000 spectrometer. Irradiance was measured at varying exposure distances, ranging from direct contact of the curing unit with the surface to a distance of 7 mm from the surface, increasing in 1 mm steps. Data were analyzed using a multivariate analysis and linear mixed models (pzirconia), CL1 (~A1/B1), CL2 (~A3/A3.5/A4/B3/B4), and CL3 (~A3.5/B3/B4/C3/D3), respectively. The highest transmitted irradiance was measured at a specimen thickness of 0.5 mm for all materials, decreasing exponentially with increased ceramic thickness. Within one type of ceramic, one thickness, and one polymerization mode, a decrease in transmitted irradiance with increased exposure distance could be observed only at a distance of 3 mm and above. Unshaded zirconia was significantly less translucent compared with the glass-ceramic, but the translucency decreased slower with material thickness. The Beer-Lambert law describes well the decrease of transmitted irradiance with an increase of the specimens' thickness for all materials. Except for dark ceramics, this would allow for calculating the transmitted irradiance through any material thickness and any initial irradiance. The amount of light passing through ceramics is an important aspect for an adhesive cementation

  3. Landsat - SRTM Shaded Relief Comparison, Los Angeles and Vicinity

    Science.gov (United States)

    2002-01-01

    Digital elevation models (DEMs), such as those produced by the Shuttle Radar Topography Mission (SRTM), allow user-controlled visualization of the Earth's landforms that is not possible using satellite imagery alone. This three-view comparison shows Los Angeles, Calif., and vicinity, with a Landsat image (only) on the left, a shaded relief rendering of the SRTM DEM on the right, and a merge of the two data sets in the middle. Note that topographic expression in the Landsat image alone is very subtle due to the fairly high sun angle (63 degrees above the horizon) during the satellite overflight in late morning of a mid-Spring day (May 4, 2001). In contrast, computer generated topographic shading of the DEM provides a pure and bold image of topographic expression with a user specified illumination direction. The middle image shows how combining the Landsat and DEM shaded relief can result in a topographically enhanced satellite image in which the information content of both data sets is merged into a single view.Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and helps in analyzing the large and growing Landsat image archive, managed by the U.S. Geological Survey (USGS).Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U

  4. Assessment of the influence of gender and skin color on the preference of tooth shade in Saudi population

    Directory of Open Access Journals (Sweden)

    Nawaf Labban

    2017-07-01

    Conclusion: Gender and skin color influences the perception of teeth shades among general population. Therefore, lighter tooth shades (BL1, BL2 for lighter skin color and comparatively darker tooth shades (BL4, B1, A1 for darker skin individuals should be prescribed as these are perceived as natural among Saudi population.

  5. Desenvolvimento de mudas de Aroeira (Schinus terebinthifolius e sombreiro (Clitoria fairchildiana sob condições de sombreamento Development of Schinus terebinthifolius and Clitoria fairchildiana seedlings under shading

    Directory of Open Access Journals (Sweden)

    Silvana de Paula Quintão Scalon

    2006-02-01

    Full Text Available Objetivou-se com este trabalho avaliar o desenvolvimento das mudas de Schinus terebinthifolius e Clitoria fairchildiana sob condiç��es de sombreamento e pleno sol. As mudas foram cultivadas sob sombrites de 70% e 50% de luz e sob luz plena. O experimento foi conduzido em DBC com 4 repetições de 20 mudas. Foram avaliados a altura do caule e o diâmetro do colo a cada vinte e um dias. Ao final do experimento foram realizadas as avaliações de peso seco total (PST-g, área foliar (AF-dm², razão de peso foliar (RPF -g/g; e peso específico de folha (PEF -g/ dm². As sementes de aroeira do campo e do sombreiro apresentaram 70% e 85% de germinação, respectivamente. S.terebinthifolius tolera bem um sombreamento moderado (70% de luz, sendo seu cultivo a pleno sol o mais indicado, pois é quando as mudas atingem menor altura (32,93 cm, diâmetro médio de 7,15 mm, maior PST (74,66 g; menor PEF (0,025; as mudas de C.fairchildiana sob condições de pleno sol não se desenvolveram satisfatoriamente, embora a altura não tenha variado entre os níveis de luz (16,39 cm, apresentaram menor diâmetro (5,32 mm, menor PST (26,22 g, menor AF (32,98 dm² e maior PEF (0,4.The objective of this work was to evaluate the development of S. terebinthifolius and C. fairchildiana seedlings under shade and full sunlight conditions. The seedlings were cultivated under 70% and 50% sunlight and full sunlight. The experiment was carried out in a randomized block design with four replications of twenty seedlings. Stem height and collar diameter were evaluated every 21 days. At the end of the experiment total dried weight (TDW-g, leaf area (LA-dm², leaf weight rate LWR-g/g and leaf specific weight (LSW-g/dm² were also evaluated. The seeds of S.terebinthifolius and C. fairchildiana showed a germination of 70% and 85% respectively. S. terebinthifolius tolerated moderate shade (70% sunligth however, full sunlight seemed to be most appropriate. C. fairchildiana

  6. Levels of shading on growth in Brazil-nut seedlings=Níveis de sombreamento no crescimento de mudas de castanheira do Brasil

    Directory of Open Access Journals (Sweden)

    Teresinha Costa Silveira de Albuquerque

    2016-02-01

    Full Text Available Efficiency initial growth of native tree seedlings may be related to adaptation ability to light environmental conditions. The objective of this study was to analyze the growth of the Brazil nut tree seedlings in the nursery under different levels of shading. The treatments tested were five environments: T75 = 75% shade; T50 = 50% shade; T25 = 25% shade; TCza = gray screen; and TPsol = full sun. The growth were evaluated after 185 days the plants remain in individual cages, measuring height, stem diameter, basal as well as the number, the length and width of the sheets. Also evaluated in chlorophyll content and calculate the chlorophyll content a, b, and total carotenoid. The results were submitted to analysis of variance and means were compared by Tukey test (p <0.05. We conclude that the environments with medium shading 25 and 50% are best suited for seedling development of the Brazil nut trees, allowing more vigorous plant growth.The plants in more shaded environments and full sun have higher levels of chlorophyll and carotenoids as an adaptive strategy. = A eficiência no crescimento inicial de árvores nativas pode ser relacionada à habilidade de adaptação de plântulas às condições luminosas do ambiente. O objetivo deste trabalho foi analisar o crescimento de mudas de castanheira do brasil, na fase de viveiro, sob diferentes níveis de sombreamento artificial. Como tratamentos testaram-se cinco ambientes: T75 = 75% de sombra; T50 = 50% de sombra; T25 = 25% de sombra; TCza = tela cinza; e TPsol = pleno sol. As avaliações de crescimento foram realizadas após 185 dias de permanência das plantas nos telados, medindo-se a altura, o diâmetro basal do caule, bem como o número, o comprimento e a largura das folhas. Avaliou-se também o teor de clorofila e o cálculo dos teores de clorofila a, b, total e carotenoides. Os resultados foram submetidos à análise de variância e as médias foram comparadas pelo teste de Tukey (p < 0

  7. Response of the Fine Root Production, Phenology, and Turnover Rate of Six Shrub Species from a Subtropical Forest to a Soil Moisture Gradient and Shading

    Science.gov (United States)

    Fu, X.; Dai, X.; Wang, H.

    2015-12-01

    Knowledge of the fine root dynamics of different life forms in forest ecosystems is critical to understanding how the overall belowground carbon cycling is affected by climate change. However, our current knowledge regarding how endogenous or exogenous factors regulate the root dynamics of understory vegetation is limited. We selected a suite of study sites representing different habitats with gradients of soil moisture and solar radiation (shading or no shading). We assessed the fine root production phenology, the total fine root production, and the turnover among six understory shrub species in a subtropical climate, and examined the responses of the fine root dynamics to gradients in the soil moisture and solar radiation. The shrubs included three evergreen species, Loropetalum chinense, Vaccinium bracteatum, and Adinandra millettii, and three deciduous species, Serissa serissoides, Rubus corchorifolius, and Lespedeza davidii. We observed that variations in the annual fine root production and turnover among species were significant in the deciduous group but not in the evergreen group. Notably, V. bracteatum and S. serissoides presented the greatest responses in terms of root phenology to gradients in the soil moisture and shading: high-moisture habitat led to a decrease and shade led to an increase in fine root production during spring. Species with smaller fine roots of the 1st+2nd-order diameter presented more sensitive responses in terms of fine root phenology to a soil moisture gradient. Species with a higher fine root nitrogen-to -carbon ratio exhibited more sensitive responses in terms of fine root annual production to shading. Soil moisture and shading did not change the annual fine root production as much as the turnover rate. The fine root dynamics of some understory shrubs varied significantly with soil moisture and solar radiation status and may be different from tree species. Our results emphasize the need to study the understory fine root dynamics

  8. Spectrophotometric Study of the Effect of Luting Agents on the Resultant Shade of Ceramic Veneers: An Invitro Study.

    Science.gov (United States)

    Jankar, Ajit Suryakant; Kale, Yogesh; Pustake, Swati; Bijjaragi, Shobha; Pustake, Bhushan

    2015-09-01

    Dentistry has found practically the best available aesthetic answer, is ceramic restoration. There are various factors that contribute to the success of ceramic veneers, like colour of underlying tooth, thickness if ceramics and the type of underlying luting cement. Shade selection and matching remains still challenge, however the shade of luting agent used for cementation of veneers produces a change in resultant shade of veneers. To compare and analyze the spectrophotometric effect of opaque and transparent luting agent on resultant shade of ceramic veneers made of 2L1.5 shade (Vitapan 3D-Masters) and B2 shade (Vitapan Classic). Out of 15 ceramic veneers of 2L1.5 shade (VITAPAN 3D- Master), seven teeth cemented with opaque cement and eight teeth with transparent cement shade of dual cure resin cement (Variolink II(TM)). Out of 10 ceramic veneers of B2 shade (VITAPAN Classic), five teeth were cemented with opaque cement and other five teeth with transparent cement shade of dual cure resin cement (Variolink II(TM)). Spectrophotometric (Macbeth U.S.A.) analysis of all ceramic veneer crowns done with optiview software and readings were recorded in Commission Internationale de I' Eclairge {CIELAB} system and dE value was calculated. Statistical analysis was done by using Paired t-test. Spectrophotometric analysis of all the veneers cemented with opaque luting agent were lighter in shade due to significant change in dL value. Veneers cemented with transparent luting agent were darker in shade due to significant change in the dL value. Opaque luting agent gives lighter shade and transparent luting agent gives darker shade to ceramic veneers fabricated with 2L1.5 and B2 shades.

  9. Demonstration of new ESP-r capability for quantifying the energy savings potential of window shading devices

    Energy Technology Data Exchange (ETDEWEB)

    Lomanowski, B.A.; Kotey, N.A.; Wright, J.L.; Collins, M.R. [Waterloo Univ., ON (Canada). Dept. of Mechanical Engineering

    2009-06-15

    The peak electricity demand in Ontario is dominated by space cooling of residential and commercial buildings. The appropriate use of window shading devices can reduce cooling energy use and lower the peak cooling load. Solar gain through glazing is the largest and most variable gain in buildings and influences energy consumption and peak cooling loads. This paper demonstrated the new modeling capability within ESP-r for windows with shading devices. The ESP-r model which considers shading options is known as the ASHWAT (ASHRAE Window Attachment) model. Measurements performed at the National Solar Test Facility (NSTF) on a full scale window with various shading attachments were compared to calculated values predicted by the ASHWAT models. The predicted results were in good agreement with measured data. Simulations illustrated the impact of different shading configurations on cooling energy, peak load and thermal comfort. A simulation of an automated external shading system highlighted the role of shading on the energy performance of a solar house design entered into the Solar Decathlon 2009 competition. The external shading design was compared with other options such as a solar protective coatings and indoor shades. Simulations also revealed the impact of shading devices on winter night-time heat loss and thermal comfort. This paper outlined the general procedure for using the shading models within ESP-r. The ASHWAT shading model was developed with emphasis on glazing/shading system generality to allow for specification of any combination of shading/glazing layers. The simulations highlighted the importance of external shading for solar protection of highly glazed facades. They also quantified the impact of glazing facade composition on cooling peak loads, cooling energy and thermal comfort. 9 refs., 7 figs.

  10. Spectrophotometric Study of the Effect of Luting Agents on the Resultant Shade of Ceramic Veneers: An Invitro Study

    Science.gov (United States)

    Kale, Yogesh; Pustake, Swati; Bijjaragi, Shobha; Pustake, Bhushan

    2015-01-01

    Introduction Dentistry has found practically the best available aesthetic answer, is ceramic restoration. There are various factors that contribute to the success of ceramic veneers, like colour of underlying tooth, thickness if ceramics and the type of underlying luting cement. Shade selection and matching remains still challenge, however the shade of luting agent used for cementation of veneers produces a change in resultant shade of veneers. Aim To compare and analyze the spectrophotometric effect of opaque and transparent luting agent on resultant shade of ceramic veneers made of 2L1.5 shade (Vitapan 3D-Masters) and B2 shade (Vitapan Classic). Materials and Methods Out of 15 ceramic veneers of 2L1.5 shade (VITAPAN 3D- Master), seven teeth cemented with opaque cement and eight teeth with transparent cement shade of dual cure resin cement (Variolink IITM). Out of 10 ceramic veneers of B2 shade (VITAPAN Classic), five teeth were cemented with opaque cement and other five teeth with transparent cement shade of dual cure resin cement (Variolink IITM). Spectrophotometric (Macbeth U.S.A.) analysis of all ceramic veneer crowns done with optiview software and readings were recorded in Commission Internationale de I’ Eclairge {CIELAB} system and dE value was calculated. Statistical Analysis Statistical analysis was done by using Paired t-test. Results Spectrophotometric analysis of all the veneers cemented with opaque luting agent were lighter in shade due to significant change in dL value. Veneers cemented with transparent luting agent were darker in shade due to significant change in the dL value. Conclusion Opaque luting agent gives lighter shade and transparent luting agent gives darker shade to ceramic veneers fabricated with 2L1.5 and B2 shades. PMID:26501014

  11. Morphophysiological Behavior and Cambial Activity in Seedlings of Two Amazonian Tree Species under Shade

    Directory of Open Access Journals (Sweden)

    Monyck Jeane dos Santos Lopes

    2015-01-01

    Full Text Available Variations in light intensity can lead to important anatomical and morphophysiological changes in plants. Aiming to increase knowledge about the Amazonian tree species, this study examines the influence of shade on the cambial activity and development of Parkia gigantocarpa Ducke and Schizolobium parahyba var. amazonicum (Huber ex Ducke Barneby seedlings. Seedlings of the two species were grown in a nursery under four shade intensities (treatments: full sun, low, moderate, and high shade (resp., 0%, 23%, 67%, and 73% of shade, or 2000, 1540, 660, and 540 µmol·m−2·s−1 obtained with polyethylene screens. We measured plant height, stem diameter, biomass production, stomatal conductance (gs, transpiration (E, photosynthesis (A, and cambial activity (CA (xylem, cambium, and phloem. Also, we calculated the Dickson Quality Index (DQI. The highest values of biomass production, gs,  E, A, and DQI, were found under full sun, in P. gigantocarpa, and under low shade intensity in S. parahyba. In both species high shade intensity reduced CA. We concluded that the CA and the physiological and morphological attributes work together, explaining the radial growth and increasing seedlings quality, which optimized efficient seedling production under full sun, in P. gigantocarpa, and under low shade intensity in S. parahyba.

  12. Influence of shade of adhesive resin cement on its polymerization shrinkage

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    Ender Akan

    2016-05-01

    Full Text Available Resin cements have the ability to bond to the tooth structure and to several indirect restorative materials and they are available in different transparency and shades. However, polymerization shrinkage remains to be a problem that leads to gap formation at the margins of restoration, and accordingly microleakage may occur. The purpose of this study was to investigate the influence of the shade of adhesive resin cement on its polymerization shrinkage. Five shades (Group 1: universal; Group 2: brown; Group 3: clear; Group 4: opaque white; Group 5: opaque yellow of a dual-cure composite cement system (Clearfil Esthetic Cement, Kuraray, Tokyo, Japan were studied with 10 specimens of each shade. Volumetric shrinkages of the composite cements of these five shades were evaluated using a video-imaging device (Acu-Vol; Bisco, Inc. by measuring the volumes before and after polymerization. Different shades displayed different volumetric shrinkages. Group 5 (2.62% and Group 2 (3.96% displayed the lowest and highest shrinkage percentages, respectively, with their respective shrinkage values being significantly different from those of the other groups (p < 0.05. The obtained results indicate that the shade of resin cement does affect its degree of polymerization shrinkage.

  13. Initial growth of Bauhinia variegata trees under different colored shade nets and light conditions

    Directory of Open Access Journals (Sweden)

    Renata Bachin Mazzini-Guedes

    2014-12-01

    Full Text Available Bauhinia variegata and B. variegata var. candida, commonly known as orchid trees, are small sized trees widely used for urban forestry and landscaping. Adult plants grow under full sun; in Brazil, however, seedlings are generally cultivated in commercial nurseries under natural half-shading. The objective of this study was to evaluate the influence of different colored shade nets and light conditions on the initial growth of B. variegata and B. variegata var. candida. The influence of six light conditions (red net with 50% shading; blue net with 50% shading; black net with 70% shading; black net with 50% shading; black net with 30% shading; and full sun on the initial growth of B. variegata and B. variegata var. candida were evaluated along 160 days, and growth relationships were calculated. Seedlings showed more efficiency on the use of photoassimilated compounds when grown under full sun. Such condition is the most appropriate for seedling production of B. variegata and B. variegata var. candida, contradicting what has been performed in practice.

  14. Shade Tree Diversity, Cocoa Pest Damage, Yield Compensating Inputs and Farmers' Net Returns in West Africa

    Science.gov (United States)

    Daghela Bisseleua, Hervé Bertin; Fotio, Daniel; Yede; Missoup, Alain Didier; Vidal, Stefan

    2013-01-01

    Cocoa agroforests can significantly support biodiversity, yet intensification of farming practices is degrading agroforestry habitats and compromising ecosystem services such as biological pest control. Effective conservation strategies depend on the type of relationship between agricultural matrix, biodiversity and ecosystem services, but to date the shape of this relationship is unknown. We linked shade index calculated from eight vegetation variables, with insect pests and beneficial insects (ants, wasps and spiders) in 20 cocoa agroforests differing in woody and herbaceous vegetation diversity. We measured herbivory and predatory rates, and quantified resulting increases in cocoa yield and net returns. We found that number of spider webs and wasp nests significantly decreased with increasing density of exotic shade tree species. Greater species richness of native shade tree species was associated with a higher number of wasp nests and spider webs while species richness of understory plants did not have a strong impact on these beneficial species. Species richness of ants, wasp nests and spider webs peaked at higher levels of plant species richness. The number of herbivore species (mirid bugs and cocoa pod borers) and the rate of herbivory on cocoa pods decreased with increasing shade index. Shade index was negatively related to yield, with yield significantly higher at shade and herb coverscocoa farms do not necessarily result in a higher net return. In conclusion, our study shows the importance of a diverse shade canopy in reducing damage caused by cocoa pests. It also highlights the importance of conservation initiatives in tropical agroforestry landscapes. PMID:23520451

  15. Are sun- and shade-type anatomy required for the acclimation of Neoregelia cruenta?

    Directory of Open Access Journals (Sweden)

    FERNANDA REINERT

    2013-06-01

    Full Text Available Sun and shade plants are often discriminated by a number of sun- and shade-type anatomies. Nonetheless, we propose that among tank-bromeliads, changes in rosette architecture satisfy the requirements for coping with contrasting light levels. The tank-bromeliad Neoregelia cruenta naturally colonises sub-habitats ranging from full exposure to direct sunlight, to shaded environments in sand ridge plains. We quantified anatomical and morphological traits of leaves and rosettes of N. cruenta grown under sun and shade conditions. Cells with undulated lateral walls within the water parenchyma are for the first time described for the family. Under high light, leaf blades were wider, shorter, and yellowish. The rosette diameter of sun plants was less than half that of shade plants. Sun leaves overlapped with neighbouring leaves for most of their length, forming a cylindrical rosette where water accumulates. Shade leaves only overlapped in the centre of the rosette. Most anatomical traits were similar under both growth conditions. Stomata were absent from the base of sun leaves, which is probably explained by limited gas exchange at the base of the tight sun-type rosette. Data suggest that the ability of N. cruenta to acclimate to sun and shade is better explained by changes in rosette architecture than by leaf anatomy.

  16. Adolescents’ use of purpose built shade in secondary schools: cluster randomised controlled trial

    Science.gov (United States)

    White, Vanessa; Wakefield, Melanie A; Jamsen, Kris M; White, Victoria; Livingston, Patricia M; English, Dallas R; Simpson, Julie A

    2009-01-01

    Objective To examine whether students use or avoid newly shaded areas created by shade sails installed at schools. Design Cluster randomised controlled trial with secondary schools as the unit of randomisation. Setting 51 secondary schools with limited available shade, in Australia, assessed over two spring and summer terms. Participants Students outside at lunch times. Intervention Purpose built shade sails were installed in winter 2005 at full sun study sites to increase available shade for students in the school grounds. Main outcome measure Mean number of students using the primary study sites during weekly observations at lunch time. Results Over the study period the mean change in students using the primary study site from pre-test to post-test was 2.63 (95% confidence interval 0.87 to 4.39) students in intervention schools and −0.03 (−1.16 to 1.09) students in control schools. The difference in mean change between groups was 2.67 (0.65 to 4.68) students (P=0.011). Conclusions Students used rather than avoided newly shaded areas provided by purpose built shade sails at secondary schools in this trial, suggesting a practical means of reducing adolescents’ exposure to ultraviolet radiation. Trial registration Exempt. PMID:19223344

  17. Effect of Ceramic Thickness and Luting Agent Shade on the Color Masking Ability of Laminate Veneers.

    Science.gov (United States)

    Begum, Zubeda; Chheda, Pratik; Shruthi, C S; Sonika, Radhika

    2014-12-01

    The main objective of the study was to recognize the effect of ceramic thickness and luting agent on the extent to which the restoration masks color variations that may be present in the underlying dental structure. Two pressable ceramics were used: Lithium disilicate reinforced (IPS e.max- Ivoclar Vivadent) and Leucite reinforced (Cergo- Dentsply). Fifteen ceramic discs were manufactured from each ceramic and divided into three groups, according to the thickness (0.5, 1, 1.5 mm). To simulate the color of a dark underlying dental structure, background discs, color C3, with 20 mm diameter, were made using resin composite. The ceramic discs with varying thicknesses were seated on the dark background of the resin composite with either resinous opaque cement or resinous cement. The color parameters were determined by the CIE Lab system of colors using a spectrophotometer and color differences (ΔE) were calculated. The results were then statistically analyzed, using ANOVA test and Tukey HSD test. The ΔE values of both ceramic systems were affected by both the luting agent and the ceramic thickness (P veneers, higher values in the color parameters were obtained for both ceramic materials. The color masking ability of ceramics used for laminate veneers is significantly affected by the thickness of the ceramic and the shade of the luting agent used.

  18. Internal wave-mediated shading causes frequent vertical migrations in fishes

    KAUST Repository

    Kaartvedt, Stein

    2012-04-25

    We provide evidence that internal waves cause frequent vertical migrations (FVM) in fishes. Acoustic data from the Benguela Current revealed that pelagic scattering layers of fish below ~140 m moved in opposite phases to internal waves, ascending ~20 m towards the wave trough and descending from the wave crest. At the trough, the downward displacement of upper waters and the upward migration of fish created an overlapping zone. Near-bottom fish correspondingly left the benthic boundary zone at the wave trough, ascending into an acoustic scattering layer likely consisting of zooplankton and then descending to the benthic boundary zone at the wave crest. We suggest that this vertical fish migration is a response to fluctuations in light intensity of 3 to 4 orders of magnitude caused by shading from a turbid surface layer that had chlorophyll a values of 3 to 4 mg m−3 and varied in thickness from ~15 to 50 m at a temporal scale corresponding to the internal wave period (30 min). This migration frequency thus is much higher than that of the common and widespread light-associated diel vertical migration. Vertical movements affect prey encounters, growth, and survival. We hypothesize that FVM increase the likelihood of prey encounters and the time for safe visual foraging among planktivorous fish, thereby contributing to efficient trophic transfer in major upwelling areas.

  19. Varying light regimes in naturally growing Jatropha curcus: pigment, proline and photosynthetic performance

    Directory of Open Access Journals (Sweden)

    Wadhwa R.

    2010-11-01

    Full Text Available Light stress is a major abiotic stress which adversely affects productivity of the plants. Tolerance to abiotic stresses is very complex, due to the intricate of interactions between stress factors and various molecular, biochemical and physiological phenomena affecting plant growth and development. In many cases, high yield potential can contribute to yield in moderate stress environment. We studied chlorophyll (Chl a fluorescence parameters and analyzed D1 core protein in one year old plants of Jatropha curcus under different light regimes (10–1200 μmol m–2 s–1 in sun and shade plants. Chl a fluorescence provides insights into the responses of the photosynthetic system to increasing irradiance. Total Chl content was 1.43 and 0.61 mg/g-1 FM for shade and sun exposed plants respectively. The effective quantum yield (ΔF/Fm' of the sun plants was lower as compared to shade plants but the amount of the D1 core protein was higher in plants grown under high light intensity. A decrease in ΔF/Fm' indicates down regulation of photosynthesis or photoinhibition. D1 protein is the membrane protein complex of the PSII reaction centre. The degradation of D1 protein may regulate the functioning of the PSII repair cycle under photoinhibitory conditions. It has been shown that low-light grown or shade plants are more susceptible to photoinhibition than high light or sun plants. This higher susceptibility is accompanied by slow degradation of damaged D1 protein. High light intensity or exposure to photooxidation leads to the irreversible damage in photosynthetic performance and consequently has an overall inhibitory effect on crop productivity.

  20. Influence of resin cement shade on the color and translucency of ceramic veneers

    Directory of Open Access Journals (Sweden)

    Daiana Kelly Lopes HERNANDES

    Full Text Available ABSTRACT Objective This in vitro study evaluated the effect of two different shades of resin cement (RC- A1 and A3 layer on color change, translucency parameter (TP, and chroma of low (LT and high (HT translucent reinforced lithium disilicate ceramic laminates. Material and Methods One dual-cured RC (Variolink II, A1- and A3-shade, Ivoclar Vivadent was applied to 1-mm thick ceramic discs to create thin RC films (100 µm thick under the ceramics. The RC was exposed to light from a LED curing unit. Color change (ΔE of ceramic discs was measured according to CIEL*a*b* system with a standard illuminant D65 in reflectance mode in a spectrophotometer, operating in the light range of 360-740 nm, equipped with an integrating sphere. The color difference between black (B and white (W background readings was used for TP analysis, while chroma was calculated by the formula C*ab=(a*2+b*2½. ΔE of 3.3 was set as the threshold of clinically unacceptable. The results were evaluated by two-way ANOVA followed by Tukey's post hoc test. Results HT ceramics showed higher ΔE and higher TP than LT ceramics. A3-shade RC promoted higher ΔE than A1-shade cement, regardless of the ceramic translucency. No significant difference in TP was noted between ceramic discs with A1- and those with A3-shade cement. Ceramic with underlying RC showed lower TP than discs without RC. HT ceramics showed lower chroma than LT ceramics, regardless of the resin cement shade. The presence of A3-shade RC resulted in higher chroma than the presence of A1-shade RC. Conclusions Darker underlying RC layer promoted more pronounced changes in ceramic translucency, chroma, and shade of high translucent ceramic veneers. These differences may not be clinically differentiable.

  1. Vegetative and productive aspects of organically grown coffee cultivars under shaded and unshaded systems

    Directory of Open Access Journals (Sweden)

    Marta dos Santos Freire Ricci

    2011-08-01

    Full Text Available Although Coffea arabica species has its origin in the African understories, there is great resistance on the part of the Brazilian producers for growing this species under agroforestry systems as they fear that shading reduces production. This study aimed at evaluating some vegetative traits and the productivity of organically grown coffee (Coffea arabica L. cultivars under shaded and unshaded systems. Twelve treatments consisting of two cultivation systems (shaded and unshaded and six coffee cultivars were arranged in randomized blocks with four replicates, in a split-plot scheme. Shading was provided by banana (Musa sp. and coral bean plants (Erythrinaverna. Shading delayed fruit maturation. Late maturation cultivars, such as the Icatu and the Obatã, matured early in both cultivation systems, while medium and early maturation cultivars presented late maturation. Cultivation in the shaded system increased the leaf area and the number of lower branches, decreased the number of productive nodes per branch, and increased the distance between the nodes and the number of leaves present in the branches. Cultivation in the unshaded system presented greater number of plants with branch blight in relation to plants grown in the shade. The productivity of the cultivars was not different, at 30.0 processed bags per hectare in the shaded system, and 25.8 processed bags per hectare in the unshaded system. The most productive cultivars in the shaded system were the Tupi, the Obatã, and the Catuaí, while no differences between cultivars were obtained in the unshaded system.

  2. Visual and instrumental shade matching using CIELAB and CIEDE2000 color difference formulas.

    Science.gov (United States)

    Pecho, Oscar E; Ghinea, Razvan; Alessandretti, Rodrigo; Pérez, María M; Della Bona, Alvaro

    2016-01-01

    To compare visual and instrumental shade matching performances using two shade guides and three color difference formulas. One hundred dental students (DS) volunteers (35 males and 65 females) with normal color vision participated in the study. The spectral reflectance of 4 extracted human upper central incisors (UCI) and shade tabs from Vita Classical (VC) and Vita Toothguide 3D-Master (3D) shade guides were measured using a spectroradiometer (SP) under D65 illuminant (diffuse/0° geometry) inside a viewing booth with a gray background. Color coordinates (CIE L*, a*, b*, C* and h°) were calculated according to CIE D65 illuminant and CIE 2° Standard Observer. Color coordinates of UCI were also evaluated using a dental spectrophotometer (EA - Easyshade Advance). DS used VC and 3D to visually select the best shade match for each UCI, under same experimental conditions used for the SP evaluation. Three color difference metrics (CIELAB, CIEDE2000(1:1:1) and CIEDE2000(2:1:1)) were used to calculate the best instrumental shade matching based on minimum color difference. The agreement between visual and instrumental shade matching was greater using SP (25-75%) than EA (0-25%). The percentage of best match for the visual assessment was more consistent using VC (23-55%) than 3D (19-34%). Considering the best performance (using SP and VC), the CIEDE2000(2:1:1) color difference formula showed the best estimate to the visual perception from DS. Within the limitations of this study, combining the use of SP, CIEDE2000(2:1:1) and Vita Classical shade guide most closely represented the visual perception of DS. Instrumental shade determination should be accompanied by experienced human visual assessment. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  3. Influence of resin cement shade on the color and translucency of ceramic veneers.

    Science.gov (United States)

    Hernandes, Daiana Kelly Lopes; Arrais, Cesar Augusto Galvão; Lima, Erick de; Cesar, Paulo Francisco; Rodrigues, José Augusto

    2016-01-01

    This in vitro study evaluated the effect of two different shades of resin cement (RC- A1 and A3) layer on color change, translucency parameter (TP), and chroma of low (LT) and high (HT) translucent reinforced lithium disilicate ceramic laminates. One dual-cured RC (Variolink II, A1- and A3-shade, Ivoclar Vivadent) was applied to 1-mm thick ceramic discs to create thin RC films (100 µm thick) under the ceramics. The RC was exposed to light from a LED curing unit. Color change (ΔE) of ceramic discs was measured according to CIEL*a*b* system with a standard illuminant D65 in reflectance mode in a spectrophotometer, operating in the light range of 360-740 nm, equipped with an integrating sphere. The color difference between black (B) and white (W) background readings was used for TP analysis, while chroma was calculated by the formula C*ab=(a*2+b*2)½. ΔE of 3.3 was set as the threshold of clinically unacceptable. The results were evaluated by two-way ANOVA followed by Tukey's post hoc test. HT ceramics showed higher ΔE and higher TP than LT ceramics. A3-shade RC promoted higher ΔE than A1-shade cement, regardless of the ceramic translucency. No significant difference in TP was noted between ceramic discs with A1- and those with A3-shade cement. Ceramic with underlying RC showed lower TP than discs without RC. HT ceramics showed lower chroma than LT ceramics, regardless of the resin cement shade. The presence of A3-shade RC resulted in higher chroma than the presence of A1-shade RC. Darker underlying RC layer promoted more pronounced changes in ceramic translucency, chroma, and shade of high translucent ceramic veneers. These differences may not be clinically differentiable.

  4. Shade of Resin-Based Luting Agents and Final Color of Porcelain Veneers.

    Science.gov (United States)

    Perroni, Ana Paula; Amaral, Camila; Kaizer, Marina R; Moraes, Rafael Ratto De; Boscato, Noéli

    2016-09-01

    This study evaluated the influence of different shades of flowable resin composite used as luting agent on the final shade of porcelain veneers of different opacities over A2 and B1 simulated dental substrate. One millimeter monolithic (enamel E1.0 or dentin D1.0) and bilayer (E0.5D0.5) porcelain discs shade A2 were paired with flowable resin composite disks (0.1 mm thick) of different shades (A1, A2, B1, white opaque - WO or IL - translucent), as veneer + luting agent (n = 10). The CIE L*a*b* color coordinates were measured with a spectrophotometer over white and black standard background, as well as over A2 and B1 simulated dental substrates. Translucency of all specimens and the shade matching of the pairs over the A2 and B1 substrates (ΔE* 00 ) were calculated by Translucency Parameter and CIEDE2000 methods. Data were statistically analyzed by 95% confidence interval. Porcelain veneer E1.0 groups were the most translucent, while the pairs veneer + luting agent WO showed the lowest translucency, and A1, A2, B1, and IL yielded little to no differences in translucency of the pairs. The overall best shade matching with A2 substrate was observed for D1.0 veneer + WO luting agent. The opacity of the porcelain veneer paired with luting agents of different shades affected the final appearance of the restorations over distinct simulated tooth substrates. Distinct shades of flowable resin composites used as luting agent might yield clinically visible color differences on porcelain veneers facilitating an excellent shade match with adjacent teeth. (J Esthet Restor Dent 28:295-303, 2016). © 2016 Wiley Periodicals, Inc.

  5. Influence of resin cement shade on the color and translucency of ceramic veneers

    Science.gov (United States)

    HERNANDES, Daiana Kelly Lopes; ARRAIS, Cesar Augusto Galvão; de LIMA, Erick; CESAR, Paulo Francisco; RODRIGUES, José Augusto

    2016-01-01

    ABSTRACT Objective This in vitro study evaluated the effect of two different shades of resin cement (RC- A1 and A3) layer on color change, translucency parameter (TP), and chroma of low (LT) and high (HT) translucent reinforced lithium disilicate ceramic laminates. Material and Methods One dual-cured RC (Variolink II, A1- and A3-shade, Ivoclar Vivadent) was applied to 1-mm thick ceramic discs to create thin RC films (100 µm thick) under the ceramics. The RC was exposed to light from a LED curing unit. Color change (ΔE) of ceramic discs was measured according to CIEL*a*b* system with a standard illuminant D65 in reflectance mode in a spectrophotometer, operating in the light range of 360-740 nm, equipped with an integrating sphere. The color difference between black (B) and white (W) background readings was used for TP analysis, while chroma was calculated by the formula C* ab=(a*2+b*2)½. ΔE of 3.3 was set as the threshold of clinically unacceptable. The results were evaluated by two-way ANOVA followed by Tukey's post hoc test. Results HT ceramics showed higher ΔE and higher TP than LT ceramics. A3-shade RC promoted higher ΔE than A1-shade cement, regardless of the ceramic translucency. No significant difference in TP was noted between ceramic discs with A1- and those with A3-shade cement. Ceramic with underlying RC showed lower TP than discs without RC. HT ceramics showed lower chroma than LT ceramics, regardless of the resin cement shade. The presence of A3-shade RC resulted in higher chroma than the presence of A1-shade RC. Conclusions Darker underlying RC layer promoted more pronounced changes in ceramic translucency, chroma, and shade of high translucent ceramic veneers. These differences may not be clinically differentiable. PMID:27556211

  6. Porcelain thickness and cement shade effects on the colour and translucency of porcelain veneering materials.

    Science.gov (United States)

    Kürklü, Duygu; Azer, Shereen S; Yilmaz, Burak; Johnston, William M

    2013-11-01

    Purposes of this in vitro study include evaluating colour changes in combinations of feldspathic porcelain and cement resulting from different thicknesses of porcelain and different shades of composite luting agent, and evaluating relative translucency parameter (RTP) values. Porcelain discs of shade A1 at nominal thicknesses of 0.5 and 1.0mm were bonded to cements of three shades in a factorial design. Colours were calculated for CIE D65 Illuminant and Standard Human Observer on black, grey and white backings. A colour difference (CD) was calculated of each possible pair of different porcelain thickness values for the same cement shade and each possible pair of different cement shades for the same porcelain thickness. RTP was analyzed by ANOVA and selected pairwise comparisons. All mean CDs studied were perceptible and most were at or greater than the clinical acceptability threshold, with the notable exception that the mean CDs and their confidence limits were below the clinical acceptability threshold for a change in porcelain thickness when utilizing the Clear cement shade. Variation in the shade of the resin luting cement will result in CDs which are near or beyond clinical acceptability. A decrease in porcelain thickness did significantly increase RTP when bonded to the resin cement shades studied. Changes in porcelain thickness or cement shade may adversely affect basic aesthetic properties of these materials. Development of methods for analyzing aesthetic effects over greater ranges of thickness for these materials would improve the prognosis for using these materials. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Physiological and behavioral responses of Nellore steers to artificial shading in an intensive production system

    Directory of Open Access Journals (Sweden)

    Diogo Alves da Costa Ferro

    2016-09-01

    Full Text Available The influence of artificial shading on environmental variables and on behavioral responses of Nellore steers in an intensive production system was evaluated in this study. The experiment was conducted in the experimental feedlot of the Department of Animal Science at Universidade Estadual de Goiás, from July to October 2014. Forty-eight male Nellore cattle with an average initial weight of 310 kg were kept in double 24-m2 stalls, in a total of 24 stalls. Of these, six were in the open air; six were covered with black shade netting of 30% light interception; six with black shade netting 50%; and six with black shade netting 80%, providing 6 m2 of shade per stall. Temperature-humidity index (THI and respiratory frequency (RF were assessed twice weekly and behavior was evaluated fortnightly during 12 h, between 06:00 h and 18.00 h. Feeding behavior, rumination, rest, and social activities such as body care and playful and abnormal activities were observed. A significant increase was found in THI and RF as the shading levels decreased, while a significant difference was recorded in rest and in other activities, water intake, and play behavior. Rest time and playful behavior increased significantly, and other activities and water intake decreased with the increase in shading levels. Shading does not change the time spent on feeding behaviors and rumination, or the frequencies of urination, defecation, cleaning other animals, self-cleaning, and social and abnormal types of behavior. The use of black shade netting of 80% light interception provides greater comfort to animals, promoting welfare and quality of life to them.

  8. Visual and instrumental evaluation of color match ability of 2 shade guides on a ceramic system.

    Science.gov (United States)

    Öngül, Değer; Şermet, Bülent; Balkaya, Mehmet Cudi

    2012-07-01

    There is limited information on the visual and instrumental evaluation of color match between a natural tooth and a ceramic crown. The purpose of this study was to evaluate the influence of 2 shade guides on color match, and to evaluate the relationship between color difference (ΔE) values and examiners' assessments of the color match in ceramic crowns. Thirty-three subjects were selected for a ceramic crown restoration of the maxillary central incisor. Two crowns were fabricated with selected shades from Vitapan Classical and Vita Toothguide 3D-Master shade guides for each subject. The color values of maxillary central incisors, selected shade tabs, and corresponding crowns were measured with a spectrophotometer. The ΔE values between the natural teeth and the crowns and between the selected shade tabs and the corresponding crowns were calculated for each subject and compared with the Student's t test (α=.05). In addition, 3 examiners visually evaluated the clinical acceptability of each crown on a scale from 1 to 6. The agreement among the examiners was assessed with the Kappa test. The scores of examiners for both shade guides were analyzed with the Wilcoxon signed rank test (α=.05). The results revealed that the color difference values between the teeth and the crowns fabricated with the selected shades from the Vita Toothguide 3D-Master shade guide were significantly smaller than those of the Vitapan Classical guide (P=.003). Similarly, the color difference values between the selected shade tabs from the Vita Toothguide 3D-Master guide and the corresponding crowns were significantly smaller than those of the Vitapan Classical guide (P=.001). However, the ΔE values obtained for both shade guides were within the clinically acceptable range (ΔE3D-Master shade guide resulted in a closer color match to the natural teeth than those of the Vitapan Classical guide. However, the ΔE values and the examiners' scores were within the clinically acceptable range for

  9. Evaluating factors that affect the shade-matching ability of dentists, dental staff members and laypeople.

    Science.gov (United States)

    Capa, Nuray; Malkondu, Ozlem; Kazazoglu, Ender; Calikkocaoglu, Senih

    2010-01-01

    The authors conducted a study to evaluate the influence of dentists' and nondentists' experience, age, sex, eye color and use of eyeglasses or contact lenses on tooth shade-matching ability. The authors included 120 participants in this study conducted in Istanbul (periodontists, oral and maxillofacial surgeons, orthodontists, endodontists, pediatric dentists, prosthodontists, restorative dentists, general dentists in private practice, dental technicians, dental assistants, dental assistant students and laypeople). The authors assigned participants to one of three groups: group 1 was composed of prosthodontists, restorative dentists and dental technicians; group 2 consisted of other dental specialists and general dentists; and group 3 included dental assistants, dental assistant students and laypeople. The authors asked participants to match the shades of three artificial maxillary right central incisors (Vitapan acrylic teeth [shades 2L1.5, 1M2, 2R1.5], Vita Zahnfabrik, Bad Säckingen, Germany) by using a shade guide system (Vita Toothguide 3D-Master, Vita Zahnfabrik). They calculated shade matching for the three color components (value, hue, chroma) and analyzed the results by using a chi(2) test. The rate of success in matching the shade for IM2 was 53.3 percent for participants in group 1, 30 percent for participants in group 2 and 20 percent for participants in group 3 (P = .017). However, there were no significant differences between the three groups for shades 2L1.5 and 2R1.5. Professional experience (P = .003) and age (P = .027) were associated with shade-matching success for tooth shade 2L1.5 only. The results showed no statistically significant differences with respect to sex, eye color or use of eyeglasses or contact lenses. Dental care professionals who routinely performed restorative procedures matched the shades better than did participants in other groups. Professional experience was associated positively with the outcome, while sex, eye color and

  10. Potential Nitrification and Nitrogen Mineral of Soil in Coffee Agroforestry System with Various Shading Trees

    Directory of Open Access Journals (Sweden)

    Purwanto .

    2007-05-01

    Full Text Available The role of shading trees in coffee farms has been well understood to establish suitable condition for the growth of coffee trees, on the other hand their role in nitrogen cycle in coffee farming is not yet well understood. The objectives of this study are to investigate the influence of various legume shading trees on the concentration of soil mineral N (N-NH4 + and N-NO3-, potential nitrification and to study the controlling factors of nitrification under field conditions. This field explorative research was carried out in Sumberjaya, West Lampung. Twelve observation plots covered four land use systems (LUS, i.e. 1 Coffee agroforestry with Gliricidiasepium as shade trees; 2 Coffee agroforestry with Gliricidiaas shade trees and Arachis pintoias cover crops; 3Coffee agroforestry with Paraserianthes falcataria as shade trees; and 4 Mixed/multistrata coffee agroforestry with Gliricidiaand other fruit crops as shade trees. Measurements of soil mineral-N concentration were carried out every three weeks for three months. Results showed that shade tree species in coffee agroforestry significantly affected concentrations of soil NH4 +, NO3- and potential nitrification. Mixed coffee agroforestry had the highest NH4+/N-mineral ratio (7.16% and the lowest potential nitrification (0.13 mg NO2-kg-1 hour -1 compared to other coffee agroforestry systems using single species of leguminous shade trees. Ratio of NH4 + /N-mineral increased 0.8—21% while potential nitrification decreased 55—79% in mixed coffee agroforestry compared to coffee agroforestry with Gliricidia or P. falcatariaas shade trees. Coffee agroforestry with P. falcatariaas shade trees had potential nitrification 53% lower and ratio of NH4 + /N-mineral concentration 20% higher than that with Gliricidia. Coffee agroforestry with P. falcataria as shade trees also had organic C content 17% higher, total N 40% higher, available P 112% higher than that with Gliricidia. The presence of A. pintoiin

  11. Integrated control of sun shades, daylight and artificial light; Integreret regulering af solafskaermning, dagslys og kunstlys

    Energy Technology Data Exchange (ETDEWEB)

    Johnsen, K.; Christoffersen, J.; Soerensen, Henrik; Jessen, G.

    2011-07-01

    The project established a basis of calculation and a practical basis for optimum choice of solar shading and integrated control strategies for both new buildings and for office, commercial and institutional buildings to be renovated with new calculation models for controlling solar shading integrated in the BSim program. A complete and applicable model for optimum, integrated solar shading control was established, focusing on thermal and visual comfort criteria towards energy consumption for heating, cooling and lighting. A prototype was tested in the daylight laboratory at Danish Building Research Institute-Aalborg University and at University of Southern Denmark. (LN)

  12. Colour parameters and shade correspondence of CAD-CAM ceramic systems.

    Science.gov (United States)

    Della Bona, Alvaro; Pecho, Oscar E; Ghinea, Razvan; Cardona, Juan C; Pérez, María M

    2015-06-01

    To evaluate colour differences between (1) CAD-CAM ceramic systems considering shades A1, A2 and A3 and the corresponding nominal shade of VC (Vita Classical shade guide) and (2) shades A1-A2, A2-A3 and A1, A2 and A3 within the same ceramic system. Samples of shades A1, A2 and A3 were fabricated (n=5) from CAD-CAM ceramic blocks (IPS e.max(®) CAD LT and HT, IPS Empress(®) CAD LT and HT, Paradigm™ C, and VITABLOCS(®) Mark II) and polished to 1.0±0.01mm in thickness. Spectral reflectance and colour coordinates were measured using a spectroradiometer inside a viewing booth using the CIE D65 illuminant and the d/0° geometry. Spectral reflectance curves were compared using VAF coefficient and were statistically analyzed using Kruskal-Wallis and the Mann-Whitney U test (α=0.05). Colour coordinates were statistically analyzed using one-way ANOVA, Tukey's test with Bonferroni correction (α=0.001). All colour differences (ΔEab(*) and ΔE00) were analyzed through comparisons with the PT - perceptibility and AT - acceptability thresholds for dental ceramics. ΔE between ceramic systems and its corresponding shade ranged from 6.32 to 13.42 (ΔEab(*)) and 4.48 to 9.30 (ΔE00). ΔE between shades A1-A2, A2-A3 and A1, A2 and A3 ranged, respectively, 1.93-4.82, 1.22-5.59 and 3.63-8.84 (ΔEab(*)); 1.54-3.87, 1.03-3.90 and 2.95-6.51 (ΔE00). Considering the corresponding nominal shade from VC, none of the ceramic systems showed colour differences below the AT. In addition, some ceramic systems showed colour differences below AT (shades A1-A2 and A2-A3) and below PT (shades A2-A3). Careful adjustments should be made to the final shade of CAD-CAM ceramic restorations to reach a clinically acceptable shade match. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Heat loads of transparent construction elements and sun shading systems; Waermelasten transparenter Bauteile und Sonnenschutzsysteme

    Energy Technology Data Exchange (ETDEWEB)

    Simmler, H.; Binder, B.; Vonbank, R.

    2000-07-01

    This report for the Swiss Federal Office of Energy (SFOE) describes a test system installed at the Swiss Federal Laboratories for Materials Testing and Research (EMPA) in Duebendorf, Switzerland, for the investigation of heat gain by glazing elements often used in modern architecture and the efficiency of shading elements. The two climatically controlled test cells for the measurement of the thermal characteristics of facade elements and shading systems are described and the results of measurements made using various types of glazing and shading systems - including external and internal lamellas, blinds and extendible fabric sunshades - are presented. The results are analysed and interpreted in a comprehensive appendix.

  14. Partial Shading Detection in Solar System Using Single Short Pulse of Load

    Directory of Open Access Journals (Sweden)

    Bartczak Mateusz

    2017-03-01

    Full Text Available A single photovoltaic panel under uniform illumination has only one global maximum power point, but the same panel in irregularly illuminated conditions can have more maxima on its power-voltage curve. The irregularly illuminated conditions in most cases are results of partial shading. In the work a single short pulse of load is used to extract information about partial shading. This information can be useful and can help to make some improvements in existing MPPT algorithms. In the paper the intrinsic capacitance of a photovoltaic system is used to retrieve occurrence of partial shading.

  15. Shade, leaf growth and crown development of Quercus rubra, Quercus velutina, Prunus serotina and Acer rubrum seedlings.

    Science.gov (United States)

    Gottschalk, Kurt W.

    1994-01-01

    The study was conducted in an open field to determine the optimum irradiance for establishment and growth of two oak species and two major associated woody species. Half-sib seedlings of black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and black oak (Q. velutina Lam.) were grown for two years under shade-cloth tents. Eight shade treatments (94, 70, 57, 45, 37, 27, 20 and 8% of full sunlight) with three replications each were used. Measurements were made on seedlings harvested at the end of the first and second growing seasons. In the second year, shading significantly decreased the number of leaves for all species except black cherry, but only significantly decreased leaf area in northern red oak. Shading significantly decreased average leaf size of red maple. Average leaf size of black cherry was largest in the intermediate shade treatments and decreased significantly with increased and decreased shade. Leaf weight/leaf area (mg cm(-2)) increased significantly in a quadratic pattern with decreasing shade for all four species. Leaf area ratio (cm(2) g(-1)) decreased significantly with decreasing shade for all species except red maple in the first year and black oak in the second year. Total branch development increased significantly with decreasing shade in red maple and northern red oak, whereas indeterminate branches increased significantly with decreasing shade only in black cherry, and short branches increased significantly with decreasing shade only in red maple.

  16. A scaleable methodology for assessing the impacts of urban shade on the summer electricity use of residential homes

    Science.gov (United States)

    Taylor, Robert Vanderlei

    Our cities are experiencing unprecedented growth while net global temperatures continue to trend warmer making sustainable urban development and energy conservation pressing public issues. This research explores how urban landscaping -- in particular trees and buildings -- affect summer electricity use in residential homes. I studied the interactions of urban shade and temperature to explore how vegetation distribution and intensity could play a meaningful role in heat mitigation in urban environments. Only a few studies have reconciled modeled electricity savings from tree shade with actual electricity consumption data. This research proposes a methodology for modeling the isolated effects of urban shade (tree shade vs building shade) on buildings' summertime electricity consumption from micro to mesoscales, empirically validating the modeled shade with actual electricity billing data, and comparing the electric energetic impact of tree shade effects with building shade effects. This proposed methodology seeks to resolve three primary research questions: 1) What are the modeled quantities of urban shade associated with the area of interest (AOI)? 2) To what extent do the effects of shading from trees and buildings mitigate summertime heat in the AOI? 2) To what extent do the shade effects from trees and buildings reduce summertime electricity consumption in the AOI?

  17. SRTM Colored and Shaded Topography: Haro and Kas Hills, India

    Science.gov (United States)

    2001-01-01

    On January 26, 2001, the Kachchh region in western India suffered the most deadly earthquake in India's history. This shaded topography view of landforms northeast of the city of Bhuj depicts geologic structures that are of interest in the study the tectonic processes that may have led to that earthquake. However, preliminary field studies indicate that these structures are composed of Mesozoic rocks that are overlain by younger rocks showing little deformation. Thus these structures may be old, not actively growing, and not directly related to the recent earthquake.The Haro Hills are on the left and the Kas Hills are on the right. The Haro Hills are an 'anticline,' which is an upwardly convex elongated fold of layered rocks. In this view, the anticline is distinctly ringed by an erosion resistant layer of sandstone. The east-west orientation of the anticline may relate to the crustal compression that has occurred during India's northward movement toward, and collision with, Asia. In contrast, the largest of the Kas Hills appears to be a tilted (to the south) and faulted (on the north) block of layered rocks. Also seen here, the linear feature trending toward the southwest from the image center is an erosion-resistant 'dike,' which is an igneous intrusion into older 'host' rocks along a fault plane or other crack. These features are simple examples of how shaded topography can provide a direct input to geologic studies.In this image, colors show the elevation as measured by the Shuttle Radar Topography Mission (SRTM). Colors range from green at the lowest elevations, through yellow and red, to purple at the highest elevations. Elevations here range from near sea level to about 300 meters (about 1000 feet). Shading has been added, with illumination from the north (image top).Elevation data used in this image was acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that

  18. Integration of eaves and shading devices for improving the thermal comfort in a multi-zone building

    Directory of Open Access Journals (Sweden)

    Haddam Muhammad Abdalkhalaq Chuayb

    2015-01-01

    Full Text Available This paper introduces a new approach to the description and modelling of multi-zone buildings in Saharan climate. Therefore, nodal method was used to apprehend thermo-aeraulic behavior of air subjected to varied solicitations. A coupling was made between equations proposed by P. Rumianowski and some equations of a building thermal energy model found in the TRNSYS user manual. Runge-Kutta fourth order numerical method was used to solve the obtained system of differential equations. Theses results show that proper design of passive houses in an arid region is based on the control of direct solar gains, temperatures and specific humidities. According to the compactness index, the insersion of solar shading and eaves can provide improved thermo-aeraulic comfort.

  19. Proposed shade guide for attached gingiva--a pilot study.

    Science.gov (United States)

    Ito, Masayasu; Marx, David B; Cheng, Ansgar C; Wee, Alvin G

    2015-04-01

    The purpose of this study was to evaluate the effect of race, age, and gender on Commision Internationale de l'Eclairage Lab color space (CIELAB) values of attached gingival colors. The color coordinates of an optimal proposed attached gingival shade guide were also determined. Participants (n = 120) were recruited to fulfill the following stratification of five age groups: 18-29, 30-39, 40-49, 50-59, and 60-85, with four racial categories (white, black, Asian, and others) and balanced for gender. Reflectance measurements of participants' attached gingiva were made using a spectroradiometer and Xenon arc lamp with a 45/0 optical configuration. A stepwise discriminant analysis was carried out to identify gingival color contribution from race, age, and gender. A hierarchical clustering analysis was used to identify color groups that clustered together. The coverage error of the proposed shade guide was calculated to the original gingival color. The stepwise discriminant analysis showed a statistically significant difference in gingival color contribution from the factors evaluated. Significant influence was found for the race/gender factors (p L*a*b* as follows: (1 = 51.0 ± 4.2, 27.7 ± 4.7, 18.3 ± 3.2), (2 = 61.4 ± 4.5, 24.3 ± 4.3, 17.6 ± 2.3), and (3 = 36.1 ± 4.1, 21 ± 4.9, 16 ± 5.2). The coverage errors to the following racial categories were: Asian (ΔE = 6.0 ± 4.8), black (ΔE = 6.7 ± 3.9), others (ΔE = 5.8 ± 2.9), and white (ΔE = 4.6 ± 2.7). The study showed that L*a*b* was significantly affected by race and gender. Clustering analysis was able to identify clusters in 120 participants for three gingival tones. © 2014 by the American College of Prosthodontists.

  20. Accuracy of shade matching performed by colour blind and normal dental students using 3D Master and Vita Lumin shade guides.

    Science.gov (United States)

    Vafaee, F; Rakhshan, V; Vafaei, M; Khoshhal, M

    2012-03-01

    The purpose of this study was to investigate whether 3D Master or VitaLumin shade guides could improve colour selection in individuals with normal and defective colour vision. First, colour perception of 260 dental students was evaluated. Afterwards, 9 colour blind and 9 matched normal subjects tried to detect colours of 10 randomly selected tabs from each kit and the correct/false answers were counted. Of the colour-defective subjects, 47.8% and 33.3% correctly detected the shade using 3D Master and VitaLumin, respectively. These statistics were 62.2% and 42.2% in normal subjects. In normal participants, but not in colour blind ones, 3D Master significantly improved shade matching accuracy compared to VitaLumin.

  1. From Fault-tolerance to Attack Tolerance

    Science.gov (United States)

    2011-04-02

    AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Means to build fault - tolerant ...bottlenecks. We also implemented a distributed storage service that uses Byzantine Quo- rum Systems (rather than state machine replication) and employs...From Fault - tolerance to Attack Tolerance AFOSR Grant F9550-06-1-0019 Final Report 1 December 2005 – 30 November 2010 Fred B. Schneider Computer

  2. USGS Small-scale Dataset - Satellite View of Alaska, with Shaded Relief 200605 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Satellite View of Alaska, with Shaded Relief map layer is a 200- meter-resolution simulated-natural-color image of Alaska. Vegetation is generally green, with...

  3. USGS Shaded Relief Large-scale Base Map Service from The National Map

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The USGS Shaded Relief Large service from The National Map (TNM) was created from the National Elevation Dataset (NED), a seamless dataset of best available raster...

  4. Color Conterminous United States Shaded Relief ? 200-Meter Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The color conterminous United States shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of the conterminous United...

  5. USGS Small-scale Dataset - Color Hawaii Shaded Relief - 200-Meter Resolution 200512 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The color Hawaii shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of Hawaii at a resolution of 200 meters. The NED is...

  6. A Low Cost Shading Analyzer and Site Evaluator Design to Determine Solar Power System Installation Area

    Directory of Open Access Journals (Sweden)

    Selami Kesler

    2015-01-01

    Full Text Available Shading analyzer systems are necessary for selecting the most suitable installation site to sustain enough solar power. Afterwards, changes in solar data throughout the year must be evaluated along with the identification of obstructions surrounding the installation site in order to analyze shading effects on productivity of the solar power system. In this study, the shading analysis tools are introduced briefly, and a new and different device is developed and explained to analyze shading effect of the environmental obstruction on the site on which the solar power system will be established. Thus, exposure duration of the PV panels to the sunlight can be measured effectively. The device is explained with an application on the installation area selected as a pilot site, Denizli, in Turkey.

  7. Satellite View of the Conterminous United States, with Shaded Relief - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Satellite View of the Conterminous United States, with Shaded Relief map layer is a 200-meter-resolution simulated-natural-color image of the United States....

  8. Color North America Shaded Relief – 1-Kilometer Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The North America Shaded Relief data were derived from the GTOPO30 elevation data. GTOPO30 is a global digital elevation model (DEM) with a horizontal grid spacing...

  9. [Effects of shading on two Sphagnum species growth and their interactions].

    Science.gov (United States)

    Ma, Jin-Ze; Bu, Zhao-Jun; Zheng, Xing-Xing; Li, Shan-Lin; Zeng, Jing; Zhao, Gao-Lin

    2012-02-01

    Taking Sphagnum palustre and S. fallax as test materials, this paper studied their growth and interactions under shading. In monoculture, shading promoted the height growth of S. palustre markedly, but had no effect on the growth of S. fallax and the biomass and branching of S. palustre. In mixed culture, S. fallax suppressed the increase of biomass and branching of S. palustre, while S. palustre had no effects on S. fallax. With the increase of shading stress, the competition of neighbour on S. fallax intensified. When the stress increased further, neighbor effect on S. fallax tended to be positive. However, the effect of neighbour on S. palustre was always competitive and did not change with the increase of shading stress.

  10. Partial Shade Stress Test for Thin-Film Photovoltaic Modules: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Silverman, Timothy J.; Deceglie, Michael G.; Deline, Chris; Kurtz, Sarah

    2015-09-02

    Partial shade of monolithic thin-film PV modules can cause reverse-bias conditions leading to permanent damage. In this work, we propose a partial shade stress test for thin-film PV modules that quantifies permanent performance loss. We designed the test with the aid of a computer model that predicts the local voltage, current and temperature stress that result from partial shade. The model predicts the module-scale interactions among the illumination pattern, the electrical properties of the photovoltaic material and the thermal properties of the module package. The test reproduces shading and loading conditions that may occur in the field. It accounts for reversible light-induced performance changes and for additional stress that may be introduced by light-enhanced reverse breakdown. We present simulated and experimental results from the application of the proposed test.

  11. Grayscale Conterminous United States Shaded Relief ? 200-Meter Resolution - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The grayscale conterminous United States shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of the conterminous United...

  12. Differences between the human eye and the spectrophotometer in the shade matching of tooth colour.

    Science.gov (United States)

    Gómez-Polo, Cristina; Gómez-Polo, Miguel; Celemin-Viñuela, Alicia; Martínez Vázquez De Parga, Juan Antonio

    2014-06-01

    The aim of this work was to assess the agreement between instrumental and visual colour matching. Shade selection with the 3DMaster Toothguide (Vita-Zahnfabrik) was performed for 1361 maxillary central incisors and compared with the shade obtained with the EasyShade Compact (Vita-Zahnfabrik) spectrophotometer. We observed a greater correlation between the objective method and the subjective one in the colour dimension of lightness (Kappa 0.6587), followed by hue (Kappa 0.4337) and finally chroma (Kappa 0.3578). The colour dimension in which the greatest agreement is seen between the operator and the spectrophotometer is value or lightness. This study reveals differences between the measurement of colour via spectrophotometry and the visual shade selection method. According to our results, there is better agreement in the value or lightness colour dimension, which is the most important one in the choice of tooth colour. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. The Art of Being Flexible: How to Escape from Shade, Salt, and Drought1

    Science.gov (United States)

    Pierik, Ronald; Testerink, Christa

    2014-01-01

    Environmental stresses, such as shading of the shoot, drought, and soil salinity, threaten plant growth, yield, and survival. Plants can alleviate the impact of these stresses through various modes of phenotypic plasticity, such as shade avoidance and halotropism. Here, we review the current state of knowledge regarding the mechanisms that control plant developmental responses to shade, salt, and drought stress. We discuss plant hormones and cellular signaling pathways that control shoot branching and elongation responses to shade and root architecture modulation in response to drought and salinity. Because belowground stresses also result in aboveground changes and vice versa, we then outline how a wider palette of plant phenotypic traits is affected by the individual stresses. Consequently, we argue for a research agenda that integrates multiple plant organs, responses, and stresses. This will generate the scientific understanding needed for future crop improvement programs aiming at crops that can maintain yields under variable and suboptimal conditions. PMID:24972713

  14. Color Alaska Shaded Relief ? 200-Meter Resolution, Albers projection - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The color Alaska shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of Alaska at a resolution of 200 meters. The NED is...

  15. USGS Small-scale Dataset - Color Alaska Shaded Relief - 200-Meter Resolution 200512 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The color Alaska shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of Alaska at a resolution of 200 meters. The NED is...

  16. Color Conterminous United States Shaded Relief ? 200-Meter Resolution, Albers projection - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The color conterminous United States shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of the conterminous United...

  17. USGS Small-scale Dataset - Satellite View of Hawaii, with Shaded Relief 200603 GeoTIFF

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Satellite View of Hawaii, with Shaded Relief map layer is a 200- meter-resolution simulated-natural-color image of Hawaii. Vegetation is generally green, with...

  18. Color Hawaii Shaded Relief ? 200-Meter Resolution, Albers projection - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The color Hawaii shaded relief data were derived from National Elevation Dataset (NED) data, and show the terrain of Hawaii at a resolution of 200 meters. The NED is...

  19. Individual Plasticity of the Shade Response of the Invasive Solidago canadensis in China

    National Research Council Canada - National Science Library

    Leshan Du; Haiyan Liu; Ming Yan; Junmin Li; Junsheng Li

    2017-01-01

      To evaluate the population variation, individual plasticity, and local adaptability of Solidago canadensis in response to shade treatment, we conducted a common pots experiment with a total of 150 ramets...

  20. Total shading system approach at Sultan Qaboos University Eco-House project

    Science.gov (United States)

    Shaaban, Awni K.; Khudhayer, Wael A.; Sukor, Nur S. Abdul

    2017-10-01

    This research presents a concept of total shading system made light weight shell that encloses the building and cut down the impact solar radiation on it. Variety of virtual shading plates were assessed by graphical shading charts, and physical models, then further refined into several types of louvers. Shading efficiencies of these louvers types were calculated and plotted and the graphs were used to compare them and select the appropriate type for each orientation. It was found out that horizontal louvers were necessary for South orientation, vertical louvers for East and West orientations, and none for North orientation. Louvers were slanted at specific angles in order cut down the low solar rays in the morning and afternoon hours, and to induce the prevailing North Easterly wind to infiltrate through and cool the cavity spaces. The findings of this research were applied and tested in the design and construction of Sultan Qaboos University Eco-House.

  1. Production and nitrogen uptake of grasses on different shading and fertilization

    Directory of Open Access Journals (Sweden)

    J Sirait

    2005-10-01

    Full Text Available An experiment was conducted in Indonesian Research Institute for Animal Production (IRIAP Bogor, West Java. The objective of this research was to study the production and nitrogen uptake of three short grasses species for grazing namely Paspalum notatum, Brachiaria humidicola, Stenotaphrum secundatum on different shading and fertilization. This experiment was arranged in split-split plot design. The main plot was shading level (0, 38, and 56%; sub-plot was fertilizer dosage (0, 100, and 200 kg N/ha while sub-sub plot was grass species. Data were analyzed by analysis of variance, and continued with Duncan multiple range test (DMRT if there were significantly different among treatments. The highest shoot production, shoot/root ratio, and crude protein content were observed on S. secundatum with 38% shading levels and 100 kg N/ha fertilizer. The higher shading level had the lower nitrogen uptake by plant, whereas the higher fertilizer dosage gave higher nitrogen uptake.

  2. Effect of time and weather on preference, frequency, and duration of shade use by horses.

    Science.gov (United States)

    Holcomb, K E; Stull, C L

    2016-04-01

    The Federation of Animal Science Societies (FASS) recommends providing access to shade for horses in hot, sunny weather at equine facilities. Previously, we found that healthy, mature domestic horses use shade with behavioral and physiological benefits during those weather conditions. The objective of this study was to characterize preference, frequency, and duration of shade use by healthy, mature horses in a Bureau of Land Management (BLM) holding facility during hot, sunny weather. The study took place at the BLM's Palomino Valley Wild Horse and Burro Center in Reno, NV, from Aug. 10 to Oct. 1, 2014. Freestanding shade structures were constructed in each of 2 drylot pens with shade cloth covering the top that blocked 98% of UV radiation. A group of 4 mares was placed in each of the 2 pens. After a 2-d acclimation period, data were recorded for 5 d, the horses were moved to the opposite pen, and data collected for an additional 5 d. This schedule was repeated for a total of 4 consecutive trials and 32 horses. Footage from time-lapse cameras was viewed at 10 s intervals between 0930 and 1700 h to record each horse's position relative to shade. Dosimeters secured to horses' halters recorded UV exposure. Automated weather stations recorded daytime ambient temperature (mean 25.9°C [SD 5.8]), relative humidity (mean 25.4% [SD 17.1]), black globe temperature (mean 29.3°C [SD 6.5] in shade and 35.8°C [SD 8.0] in unshaded area), and solar radiation (mean 595 W/m [SD 235]). Horses spent 10.9% more time in shade than by chance ( horse (SD 66.9), comprising 17.1 bouts (SD 12.1) with an average bout length of 6.3 min (SD 3.4). The mean daily UV Index experienced by horses in these partially shaded drylots was 1.52 (SD 0.58) compared with 3.4 (SD 1.5) for a control instrument in the sun. Horses used shade more on the sunniest days and greater than just by chance at all hours of the day, with greatest use in the morning before peak ambient temperature. This study supports

  3. Shape-from-shading using the heat equation.

    Science.gov (United States)

    Robles-Kelly, Antonio; Hancock, Edwin R

    2007-01-01

    This paper offers two new directions to shape-from-shading, namely the use of the heat equation to smooth the field of surface normals and the recovery of surface height using a low-dimensional embedding. Turning our attention to the first of these contributions, we pose the problem of surface normal recovery as that of solving the steady state heat equation subject to the hard constraint that Lambert's law is satisfied. We perform our analysis on a plane perpendicular to the light source direction, where the z component of the surface normal is equal to the normalized image brightness. The x - y or azimuthal component of the surface normal is found by computing the gradient of a scalar field that evolves with time subject to the heat equation. We solve the heat equation for the scalar potential and, hence, recover the azimuthal component of the surface normal from the average image brightness, making use of a simple finite difference method. The second contribution is to pose the problem of recovering the surface height function as that of embedding the field of surface normals on a manifold so as to preserve the pattern of surface height differences and the lattice footprint of the surface normals. We experiment with the resulting method on a variety of real-world image data, where it produces qualitatively good reconstructed surfaces.

  4. Measurement of bidirectional optical properties of complex shading devices

    Energy Technology Data Exchange (ETDEWEB)

    Klems, J.H.; Warner, J.L.

    1995-01-01

    A new method of predicting the solar heat gain through complex fenestration systems involving nonspecular layers such as shades or blinds has been examined in a project jointly sponsored by ASHRAE and DOE. In this method, a scanning radiometer is used to measure the bidirectional radiative transmittance and reflectance of each layer of a fenestration system. The properties of systems containing these layers are then built up computationally from the measured layer properties using a transmission/multiple-reflection calculation. The calculation produces the total directional-hemispherical transmittance of the fenestration system and the layer-by-layer absorptances. These properties are in turn combined with layer-specific measurements of the inward-flowing fractions of absorbed solar energy to produce the overall solar heat gain coefficient. This paper describes the method of measuring the spatially averaged bidirectional optical properties using an automated, large-sample gonioradiometer/photometer, termed a ``Scanning Radiometer.`` Property measurements are presented for one of the most optically complex systems in common use, a venetian blind. These measurements will form the basis for optical system calculations used to test the method of determining performance.

  5. Impact of shading on daylight quality. Simulations with radiance

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, M.C.

    2001-07-01

    The impact of six exterior shading devices on daylight quality and on the potential for daylight utilisation in a standard, south-oriented office room was investigated through computer simulations with Radiance. The daylight quality was evaluated by considering four performance indicators: the absolute work plane illuminance, the illuminance uniformity on the work plane, the absolute luminance in the visual field and the luminance ratios between the work plane, VDT screen and surrounding surfaces. The results indicate that the overhang, white awning and horizontal venetian blind generated work plane illuminance levels that are more suitable for offices where traditional tasks are carried out. However, these devices did not prevent high luminance values at the window. On the other hand, the grey specular screen produced unacceptably low work plane illuminance, poor illuminance uniformity and unacceptably low luminance levels which resulted in unsuitable luminance ratios between the VDT screen, work plane and surroundings. The 45 deg venetian blind, white screen and blue awning provided work plane illuminance levels suitable for offices where a combination of paper and computer work is carried out. They also provided acceptable illuminance uniformity on the work plane, suitable luminance ratios between the work plane, VDT screen and surroundings and they significantly reduced the luminance of the window. However, the blue awning had a poorer performance in December than in June and the white screen resulted in high luminance values at the window, which indicates that the best device among the ones studied was the 45 deg venetian blind.

  6. Microleakage in class V gingiva-shaded composite resin restorations.

    Science.gov (United States)

    Poggio, Claudio; Chiesa, Marco; Dagna, Alberto; Colombo, Marco; Scribante, Andrea

    2012-01-01

    The purpose of this study was to evaluate the microleakage in Class V cavities restored with a new gingiva-shaded microhybrid composite resin and with a conventional microhybrid composite resin using three different dentin bonding systems (DBS). Class V cavities were prepared in sixty freshly extracted human teeth with the incisal margin in enamel and the apical margin in dentin/cementum. Restored specimens, after thermocycling, were placed in 2% methylene blue solution for 24 hours. Longitudinal sections were obtained and studied with a stereomicroscope for assessment of the microleakage according to degree of dye penetration (scale 0-3). Data were analyzed with Kruskal-Wallis test and with Mann-Whitney U-test.IN THIS STUDY THERE WAS NO LEAKAGE IN ENAMEL: all the cavities showed no dye penetration at the incisal margins (located in enamel). None of the DBS used eliminated microleakage in apical margins (located in dentin or cementum): three-step total-etch and single-step self-etch were more effective in reducing microleakage in dentin margins when compared with two-step total-etch. This in vitro study concluded that microleakage in Class V cavities restored with the composite resins tested is similar.

  7. Representasi Perempuan Dalam Film (Analisis Semiotika Representasi Perempuan Dalam Film “Fifty Shades of Grey”)

    OpenAIRE

    Aviomeita, Friska

    2016-01-01

    This study entitled "Representation of Women In Film ( Roland Barthes Semiotics Analysis In the film Fifty Shades of Grey ) " . The purpose of this study to find out how women are represented in the film " Fifty Shades of Grey " by denotation , connotation and myths . Film has always influenced and shaped the public based on the contents of the message behind it. Messages or values contained in the film may affect the audience. In this study, researchers used several theorie...

  8. The effect of shading on the flexural strength of zirconia- based ceramic Rainbow

    Directory of Open Access Journals (Sweden)

    Marzieh Alikhasi

    2013-08-01

    Full Text Available   Background and Aims: Along with the advances in dental materials and invention of new techniques for ceramic producion, the demand for the beauty and matching restoration’s color with patient’s natural teeth is growing. Nowadays, zirconia systems are the focus of attention. Despite their strength, one of the problems with such systems is the high opacity and failing to provide the favored color. Considering few studies about the influence of shading on Zirconia, the purpose of this in vitro study was to evaluate the effect of different shading of zirconia-based ceramics on the biaxial flexural strength .   Materials and Methods: In this in vitro experimental study, Rainbow (Dentium, Korea zirconia-based ceramics (the diameter of 15mm and 1mm in thick were divided into four groups of 10 specimens. According to Vita shade guide system and manufacturer’s time recommendations (3 seconds, three groups of disc specimens were shaded to A3, B3 and D3 colors and other ten specimens remained uncolored as control group. The biaxial flexural strength test of discs was evaluated and the elements’ composition of colors was detected by Energy Dispersiue X-ray Microanalysisd (EDX. Finally, data were analyzed using one-way ANOVA and Post-hoc tests.   Results: The biaxial flexural strength in non colored specimens, A3 shaded discs, B3 shaded, and D3 shaded specimens were determined 1061.93, 819.16, 1100.10, and 825.48 MPa respectively which was statistically significant among groups (P<0.001. The statistical analysis revealed that the highest strength in B3 and non colored groups which were significantly higher than A3 and D3. EDX analysis showed significant differences among different colored compositions.   Conclusion: The biaxial flexural strength of zirconia cores are affected by shading and the specific selected color.

  9. Vitapan 3D-master shade guide showed no fluorescence emission

    OpenAIRE

    Yong-Keun Lee; Bin Yu; Ho-Nam Lim

    2012-01-01

    Objectives: To determine the fluorescence property of Vitapan 3D-Master shade guide tabs with a spectrophotometer. Materials and Methods: Fluorescence property of 29 shade tabs, in both of original and ground-to-flat forms, was determined by a reflection spectrophotometer. Color difference (ΔEFNx01ab-FL) by the inclusion and exclusion of the UV component of a standard daylight simulator (CIE standard illuminant D65) was calculated to determine the fluorescence color change. Fluorescence p...

  10. Photovoltaic Shading Testbed for Module-Level Power Electronics: 2016 Performance Data Update

    Energy Technology Data Exchange (ETDEWEB)

    Deline, Chris [National Renewable Energy Lab. (NREL), Golden, CO (United States); Meydbray, Jenya [PV Evolution Labs (PVEL), Davis, CA (United States); Donovan, Matt [PV Evolution Labs (PVEL), Davis, CA (United States)

    2016-09-01

    The 2012 NREL report 'Photovoltaic Shading Testbed for Module-Level Power Electronics' provides a standard methodology for estimating the performance benefit of distributed power electronics under partial shading conditions. Since the release of the report, experiments have been conducted for a number of products and for different system configurations. Drawing from these experiences, updates to the test and analysis methods are recommended. Proposed changes in data processing have the benefit of reducing the sensitivity to measurement errors and weather variability, as well as bringing the updated performance score in line with measured and simulated values of the shade recovery benefit of distributed PV power electronics. Also, due to the emergence of new technologies including sub-module embedded power electronics, the shading method has been extended to include power electronics that operate at a finer granularity than the module level. An update to the method is proposed to account for these emerging technologies that respond to shading differently than module-level devices. The partial shading test remains a repeatable test procedure that attempts to simulate shading situations as would be experienced by typical residential or commercial rooftop photovoltaic (PV) systems. Performance data for multiple products tested using this method are discussed, based on equipment from Enphase, Solar Edge, Maxim Integrated and SMA. In general, the annual recovery of shading losses from the module-level electronics evaluated is 25-35%, with the major difference between different trials being related to the number of parallel strings in the test installation rather than differences between the equipment tested. Appendix D data has been added in this update.

  11. Reception Analysis to Female Reader in Indonesia About Sadomasochism on Fifty Shades of Grey Novels

    OpenAIRE

    Gracia Samosir, Dhita; Dwiningtyas, S.Sos, MA, Dr. Hapsari

    2016-01-01

    This research is used to see differences interpretation on female reader group about sadomasochism on novel Fifty Shades of Grey. Text on the media, on this case on novel Fifty Shades of Grey offering the reader to understand sadomasochism as a sexual activity which can give sexual pleasure as a preferred reading, the dominant meaning from text's novel then compared to interview result's analysis towards female reader, specifically in Indonesia. The research is aim to look the social values c...

  12. Effect of late planting and shading on cellulose synthesis during cotton fiber secondary wall development.

    Directory of Open Access Journals (Sweden)

    Ji Chen

    Full Text Available Cotton-rapeseed or cotton-wheat double cropping systems are popular in the Yangtze River Valley and Yellow River Valley of China. Due to the competition of temperature and light resources during the growing season of double cropping system, cotton is generally late-germinating and late-maturing and has to suffer from the coupling of declining temperature and low light especially in the late growth stage. In this study, late planting (LP and shading were used to fit the coupling stress, and the coupling effect on fiber cellulose synthesis was investigated. Two cotton (Gossypium hirsutum L. cultivars were grown in the field in 2010 and 2011 at three planting dates (25 April, 25 May and 10 June each with three shading levels (normal light, declined 20% and 40% PAR. Mean daily minimum temperature was the primary environmental factor affected by LP. The coupling of LP and shading (decreased cellulose content by 7.8%-25.5% produced more severe impacts on cellulose synthesis than either stress alone, and the effect of LP (decreased cellulose content by 6.7%-20.9% was greater than shading (decreased cellulose content by 0.7%-5.6%. The coupling of LP and shading hindered the flux from sucrose to cellulose by affecting the activities of related cellulose synthesis enzymes. Fiber cellulose synthase genes expression were delayed under not only LP but shading, and the coupling of LP and shading markedly postponed and even restrained its expression. The decline of sucrose-phosphate synthase activity and its peak delay may cause cellulose synthesis being more sensitive to the coupling stress during the later stage of fiber secondary wall development (38-45 days post-anthesis. The sensitive difference of cellulose synthesis between two cultivars in response to the coupling of LP and shading may be mainly determined by the sensitiveness of invertase, sucrose-phosphate synthase and cellulose synthase.

  13. Performance assessment of Vita Easy Shade spectrophotometer on colour measurement of aesthetic dental materials.

    Science.gov (United States)

    AlGhazali, N; Burnside, G; Smith, R W; Preston, A J; Jarad, F D

    2011-12-01

    Four different shades were used to produce 20 samples of resin-based composite and 20 samples of porcelain to evaluate the performance ability of an intra oral test spectrophotometer compared to a reference spectrophotometer. The absolute colour coordinates CIELAB values measured with both spectrophotometers were significantly different (p spectrophotometers (p < 0.05). Therefore, the Easy Shade can be used in dental practice and dental research with some limitations.

  14. In vitro and in vivo evaluations of three computer-aided shade matching instruments.

    Science.gov (United States)

    Yuan, Kun; Sun, Xiang; Wang, Fu; Wang, Hui; Chen, Ji-hua

    2012-01-01

    This study evaluated the accuracy and reliability of three computer-aided shade matching instruments (Shadepilot, VITA Easyshade, and ShadeEye NCC) using both in vitro and in vivo models. The in vitro model included the measurement of five VITA Classical shade guides. The in vivo model utilized three instruments to measure the central region of the labial surface of maxillary right central incisors of 85 people. The accuracy and reliability of the three instruments in these two evaluating models were calculated. Significant differences were observed in the accuracy of instruments both in vitro and in vivo. No significant differences were found in the reliability of instruments between and within the in vitro and the in vivo groups. VITA Easyshade was significantly different in accuracy between in vitro and in vivo models, while no significant difference was found for the other two instruments. Shadepilot was the only instrument tested in the present study that showed high accuracy and reliability both in vitro and in vivo. Significant differences were observed in the L*a*b* values of the 85 natural teeth measured using three instruments in the in vivo assessment. The pair-agreement rates of shade matching among the three instruments ranged from 37.7% to 48.2%, and the incidence of identical shade results shared by all three instruments was 25.9%. As different L*a*b* values and shade matching results were reported for the same tooth, a combination of the evaluated shade matching instruments and visual shade confirmation is recommended for clinical use.

  15. Increased light-use efficiency sustains net primary productivity of shaded coffee plants in agroforestry system.

    Science.gov (United States)

    Charbonnier, Fabien; Roupsard, Olivier; le Maire, Guerric; Guillemot, Joannès; Casanoves, Fernando; Lacointe, André; Vaast, Philippe; Allinne, Clémentine; Audebert, Louise; Cambou, Aurélie; Clément-Vidal, Anne; Defrenet, Elsa; Duursma, Remko A; Jarri, Laura; Jourdan, Christophe; Khac, Emmanuelle; Leandro, Patricia; Medlyn, Belinda E; Saint-André, Laurent; Thaler, Philippe; Van Den Meersche, Karel; Barquero Aguilar, Alejandra; Lehner, Peter; Dreyer, Erwin

    2017-08-01

    In agroforestry systems, shade trees strongly affect the physiology of the undergrown crop. However, a major paradigm is that the reduction in absorbed photosynthetically active radiation is, to a certain extent, compensated by an increase in light-use efficiency, thereby reducing the difference in net primary productivity between shaded and non-shaded plants. Due to the large spatial heterogeneity in agroforestry systems and the lack of appropriate tools, the combined effects of such variables have seldom been analysed, even though they may help understand physiological processes underlying yield dynamics. In this study, we monitored net primary productivity, during two years, on scales ranging from individual coffee plants to the entire plot. Absorbed radiation was mapped with a 3D model (MAESPA). Light-use efficiency and net assimilation rate were derived for each coffee plant individually. We found that although irradiance was reduced by 60% below crowns of shade trees, coffee light-use efficiency increased by 50%, leaving net primary productivity fairly stable across all shade levels. Variability of aboveground net primary productivity of coffee plants was caused primarily by the age of the plants and by intraspecific competition among them (drivers usually overlooked in the agroforestry literature) rather than by the presence of shade trees. © 2017 John Wiley & Sons Ltd.

  16. Species abundance and potential biological control services in shade vs. sun coffee in Puerto Rico

    Science.gov (United States)

    Borkhataria, Rena R.; Collazo, Jaime A.; Groom, Martha J.

    2012-01-01

    Birds, lizards and insects were surveyed in three sun and three shade coffee plantations in Puerto Rico to provide a comprehensive comparison of biodiversity between plantations types and to identify potential interrelationships (e.g., biological or natural control services) between members of each taxon and coffee pests. Abundance of avian species, including insectivorous species, was significantly higher in shade coffee. Anolis cristatellus and A. stratulus were significantly more abundant in sun plantations whereas A. gundlachi and A. evermanni were detected more frequently in shade plantations. Insects in the orders Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera, Neuroptera, and Psocoptera were significantly more abundant in shade coffee, while orthopterans were more abundant in sun. The coffee leaf miner (Leucoptera coffeela) and the flatid planthopper (Petrusa epilepsis) did not differ significantly between plantation types, nor did the abundance of the wasp complex that parasitizes the coffee leaf miner. These findings confirmed that shade plantations harbor a wide array of elements of biodiversity; but sun plantations may also harbor many elements of biodiversity, and in some cases, in higher abundance than in shade plantations.

  17. SHADING AND SUBSTRATE ON THE PRODUCTION OF SEEDLINGS OF Erythrina velutina Willd.

    Directory of Open Access Journals (Sweden)

    Laércio Wanderley dos Santos

    2013-12-01

    Full Text Available http://dx.doi.org/10.5902/1980509812341Erythrina velutina Willd. (Fabaceae is used in traditional medicine in northeastern Brazil for its sudorificproperties, soothing, emollient, pectoral and local anesthetic. The aim of this study was to evaluate theeffect of substrate and shading on seedlings of Erythrina velutina. The experimental design was completelyrandomized in factorial scheme 5 x 2 (five substrates and two shades, with four replications and 10 plantsin each plot. The substrates were arisco, arisco + cattle manure 2:1 v/v, arisco + cattle manure 3:1 v/v, sand+ cattle manure 2:1 v/v, sand + cattle manure 3:1 v/v. The shadings were 0% shading (full sunlight and50% shading. The characteristics evaluated were stem diameter, height, leaf area, green and dry biomass ofroots and shoots, height/diameter and Dickson quality index.There was no significant difference in diameterbetween the different substrates. The environment in full sun favored the diameter and the root biomasswhereas the height was favored by shade. The substrates with cattle manure in its composition favorsthe development of plants of Erythrina velutina and higher seedling quality are produced in full sun andsubstrate arisco + cattle manure in the ratio 2:1

  18. Biological and nutritional properties of blackcurrant berries (Ribes nigrum L.) under conditions of shading nets.

    Science.gov (United States)

    Djordjevic, Boban; Šavikin, Katarina; Djurovic, Dejan; Veberic, Robert; Mikulič Petkovšek, Maja; Zdunić, Gordana; Vulic, Todor

    2015-09-01

    Changes of environmental factors, created under the influence of various shading nets, could significantly affect the biological characteristics of plants grown in such conditions as well as biosynthesis of primary metabolites and ascorbic acid. Five blackcurrant cultivars - 'Ben Sarek', 'Ben Nevis', 'Ben Lomond', 'Ometa' and 'Čačanska Crna' - were cultivated in the shade of two green polyethylene nets and exposed to direct sunlight during two experimental seasons. In the control treatment, all cultivars contained the highest amounts of soluble solid content and number of flower buds per shoot in both years of cultivation. The bushes exposed to direct sunlight had the highest sunburn damage to the berries and leaves, and loss of yield. The greatest yield loss caused by berry damage in the present study during the experimental period was in cultivar 'Ben Sarek': 9.0% in 2010 and 15.4% in 2011. Growing in the shade of light-green net contributed the highest content of ascorbic acid. Control bushes and those shaded by light-green net had significantly higher radical scavenging activity, with values between 1.15 and 1.22 mg mL(-1). Plants shaded by nets in both years of cultivation had lower damage to leaves and berries and percentage of loss of yield, and usage of the net would be economically advantageous to growers. Fruit of blackcurrant cultivars grown in shading conditions still represent a good source of valuable nutritive and biologically active compounds. © 2014 Society of Chemical Industry.

  19. Shade tree diversity, cocoa pest damage, yield compensating inputs and farmers' net returns in West Africa.

    Science.gov (United States)

    Bisseleua Daghela, Hervé Bertin; Bisseleua, Hervé Bertin Daghela; Fotio, Daniel; Yede; Missoup, Alain Didier; Vidal, Stefan

    2013-01-01

    Cocoa agroforests can significantly support biodiversity, yet intensification of farming practices is degrading agroforestry habitats and compromising ecosystem services such as biological pest control. Effective conservation strategies depend on the type of relationship between agricultural matrix, biodiversity and ecosystem services, but to date the shape of this relationship is unknown. We linked shade index calculated from eight vegetation variables, with insect pests and beneficial insects (ants, wasps and spiders) in 20 cocoa agroforests differing in woody and herbaceous vegetation diversity. We measured herbivory and predatory rates, and quantified resulting increases in cocoa yield and net returns. We found that number of spider webs and wasp nests significantly decreased with increasing density of exotic shade tree species. Greater species richness of native shade tree species was associated with a higher number of wasp nests and spider webs while species richness of understory plants did not have a strong impact on these beneficial species. Species richness of ants, wasp nests and spider webs peaked at higher levels of plant species richness. The number of herbivore species (mirid bugs and cocoa pod borers) and the rate of herbivory on cocoa pods decreased with increasing shade index. Shade index was negatively related to yield, with yield significantly higher at shade and herb coverstropical agroforestry landscapes.

  20. Seasonal contrasts in the response of coffee ants to agroforestry shade-tree management.

    Science.gov (United States)

    Teodoro, A V; Sousa-Souto, L; Klein, A-M; Tscharntke, T

    2010-12-01

    In many tropical landscapes, agroforestry systems are the last forested ecosystems, providing shade, having higher humidity, mitigating potential droughts, and possessing more species than any other crop system. Here, we tested the hypothesis that higher levels of shade and associated humidity in agroforestry enhance coffee ant richness more during the dry than rainy season, comparing ant richness in 22 plots of three coffee agroforestry types in coastal Ecuador: simple-shade agroforests (intensively managed with low tree species diversity), complex-shade agroforests (extensively managed with intermediate tree species diversity) and abandoned coffee agroforests (abandoned for 10-15 yr and resembling secondary forests). Seasonality affected responses of ant richness but not composition to agroforestry management, in that most species were observed in abandoned coffee agroforests in the dry season. In the rainy season, however, most species were found in simple-shade agroforests, and complex agroforestry being intermediate. Foraging coffee ants species composition did not change differently according to agroforestry type and season. Results show that shade appears to be most important in the dry seasons, while a mosaic of different land-use types may provide adequate environmental conditions to ant species, maximizing landscape-wide richness throughout the year. © 2010 Entomological Society of America

  1. Effect of shading nets on the production and quality of blueberry fruit (Vaccinium corymbosum L. cv. Brigitta

    Directory of Open Access Journals (Sweden)

    Mario Marcelo Rodríguez Beraud

    2015-03-01

    Full Text Available Growth, development and fruit quality blueberry (Vaccinium corymbosum L. variety Brigitta under different shade nets were evaluated. Assays were performed in plants 7 years in a commercial orchard Collipulli, Araucanía Region, Chile. Treatments were a control without shading and four types of screens: a red 40% and 18% shade; aluminized mesh with 40% shade and a black mesh 35% shade. In fruits shade of red mesh 40% greater equatorial and polar diameter were observed and three weeks later harvested the fruits of treatment without mesh. In growing shade 40% aluminized mesh phenological stages extension lag and the maximum weekly production two weeks over control was observed. The highest yields were observed in plants of treatment and control shade of red mesh 40%, with 11008 kg ha-1 and 10461 kg ha-1, respectively, while the lowest was in red mesh 18% with 9668 kg ha-1. The fruits grown under shade of red mesh 18% showed the highest number of fruits per plant with 1806 berries per plant, fruit weight less than 1.69 g with the strongest with 3.76 N mm-1 module deformability. Therefore, the largest weight berry fruits observed in non-mesh screen and 40% red shading, together with the increased size and performance.

  2. Using tolerance bounds in scientific investigations

    Energy Technology Data Exchange (ETDEWEB)

    Wendelberger, J.R.

    1996-07-01

    Assessment of the variability in population values plays an important role in the analysis of scientific data. Analysis of scientific data often involves developing a bound on a proportion of a population. Sometimes simple probability bounds are obtained using formulas involving known mean and variance parameters and replacing the parameters by sample estimates. The resulting bounds are only approximate and fail to account for the variability in the estimated parameters. Tolerance bounds provide bounds on population proportions which account for the variation resulting from the estimated mean and variance parameters. A beta content, gamma confidence tolerance interval is constructed so that a proportion beta of the population lies within the region bounded by the interval with confidence gamma. An application involving corrosion measurements is used to illustrate the use of tolerance bounds for different situations. Extensions of standard tolerance intervals are applied to generate regression tolerance bounds, tolerance bounds for more general models of measurements collected over time, and tolerance intervals for varying precision data. Tolerance bounds also provide useful information for designing the collection of future data.

  3. PowerShades II. Optimisation and validation of highly transparent photovoltaic. Final report

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-15

    The objective of the project is continued development and validation of a novel Danish photovoltaic product with the work title ''PowerShade''. The PowerShade insulating glazing unit (IGU) is a combination of a strong solar shading device and a power producing photovoltaic coating. The core technology in the PowerShade IGU is a thin film silicon photovoltaic generator applied to a micro structured substrate. The geometry of the substrate provides the unique combination of properties that characterizes the PowerShade module - strong progressive shading, high transparency, and higher electrical output than other semitransparent photovoltaic products with similar transparencies. The project activities fall in two categories, namely development of the processing/product and validation of the product properties. The development part of the project is focussed on increasing the efficiency of the photovoltaic generator by changing from a single-stack type cell to a tandem-stack type cell. The inclusion of PowerShade cells in insulating glazing (IG) units is also addressed in this project. The validation part of the project aims at validation of stability, thermal and optical properties as well as validation of the electrical yield of the product. The validation of thermal and optical properties has been done using full size modules installed in a test facility built during the 2006-08 ''PowerShades'' project. The achieved results will be vital in the coming realisation of a commercial product. Initial processing steps have been automated, and more efficient tandem-type solar cells have been developed. A damp heat test of an IGU has been carried out without any degradation of the solar cell. The PowerShade module assembly concept has been further developed and discussed with different automation equipment vendors and a pick-and-place tool developed. PowerShade's influence on the indoor climate has been modelled and verified by

  4. Solar Shading in Low Energy Office Buildings - Design Strategy and User Perception

    Directory of Open Access Journals (Sweden)

    Steinar Grynning

    2017-06-01

    Full Text Available The objective of this paper is to investigate the visual comfort and quality of daylight in modern office buildings in the Nordic climate. A study of various daylight-related aspects and qualities was carried out for three different office buildings, using a combination of quantitative and qualitative methods. The focus was on a combination of user perception of daylight quality and assessment of the daylight amount and quality, by using the daylight factor (DF and useful daylight illuminance parameters. Previous studies and experiences from construction examples indicate that users, in general, complain about lack of manual control of systems and too low daylight levels, even if the requirements in the building codes are satisfied. Furthermore, they complain about control algorithms of the shading devices, which cause undesired automatic opening and closure of such devices. Thus, causing disturbances and irritation amongst the users. Hence, interviews with key personnel in a modern and architecturally acclaimed office building were carried out in addition to an in-depth analysis of previous surveys of a zero-energy office building. It was found that automatic moveable shading can be regarded as a source of discomfort. This is due to the lack of manual-control override possibilities, which causes disturbances due to the system moving up and down. In one of the offices, the users disabled the exterior shading system. However, the external fixed shading and the internal manually operated roller blinds were found to be satisfactory. The results from a previous study showed that the users in the Marche building are in general satisfied with the daylight. One of the main reasons for this, according to the users, is that they have manual control of the shading system. Manual control of the shading systems is preferred by users in the office buildings studied. Daylight simulations showed that the external fixed shading system combined with internal

  5. The Implementation of Elaborative Feedback for Qualitative Improvement of Shade Matching-A Randomized Study.

    Science.gov (United States)

    Olms, Constanze; Jakstat, Holger A; Haak, Rainer

    2016-09-01

    The objective of this prospective learning research study is to examine the impact of structured elaborative feedback in practical skills teaching of visual and digital shade matching. A total of 60 preclinical dental students participated in the study. The mean average age was 23 years, of which 37 were female (61.7%) and 23 male (38.3%). The participants were randomly divided into a study and control group (n = 30 each). Recording of shade matching was carried out on the phantom patient using clinically simulated settings with elaborative feedback in the study group (T1). Nine items were recorded for visual shade matching and six items for digital shade-taking. The errors were coded. The lower the total (max. 30 points), the fewer the errors made by students during shade determination. The subject labeled the tooth color using VITA 3D-Master and VITA Easyshade (Vita Zahnfabrik, Bad Säckingen, Germany). On comparing the two groups, the study group and the control group showed a similar mean error value at reference time T1. After intervention (T2) it was possible to achieve a clear improvement in the rate of errors for study group. In the study group there was a significant difference between the ΔE values from time T1 and T2 of visual shade matching (p <0.05). The digital ΔE values show in total no significant changes. Elaborative feedback in conjunction with standardized checklists can lead to a substantial improvement among students in terms of visual shade matching. Correctly determining the tooth shade is an essential treatment step in esthetic reconstructive dentistry. Color is probably one of the most important determinants of esthetics in dentistry. Factors such as lighting conditions, gender, age, experience, and color vision impairment affect the process of shade matching. With an elaborative feedback in conjunction with standardized checklists can lead to a substantial improvement among students in terms of visual shade matching. (J Esthet Restor

  6. Shades of irony in the anti-language of Amos

    Directory of Open Access Journals (Sweden)

    William Domeris

    2016-05-01

    Full Text Available The rhetoric of Amos includes a wonderful mixture of humour and threat, sarcasm and irony, hyperbole and prediction. Holding the fabric of this conversation together is Amos’s place within the prophetic minority – the Yahweh-only party (his anti-society. Making use of sociolinguistics, and particularly the idea of anti-language, I take a closer look at Amos, including his use of overlexicalisation, insider-humour and all the shades of irony one might expect. Typically of a member of an anti-society, Amos exaggerates the differences between insider and outsider, in this case, speaking of ‘ivory houses’, ‘the cattle of Bashan’ while appealing to his successful attempts to save the rich from the wrath of God. The offenses of the outsiders are sometimes crystal clear and at other times shrouded in metaphor, and so too is the fate of these people. In reading Amos, we are constantly in danger of falling victim to the persuasive power of his rhetoric. We are drawn into the world of Amos, quickly accepting his boundaries and the ideology of his anti-society, his depiction of reality and his stark caricature of the rich. The rhetoric is persuasive and the irony is divisive forcing a choice of black and white, believer and unbeliever, rich and poor, oppressors and oppressed. We struggle to swim against the current and instead long to respond to Amos’s invitation to live (Am 5:5 – perhaps even to discover that elusive hope at which the book hints: Most of history has been the forging of structures of security and appropriate loyalty symbols, to announce and defend one’s personal identity, one’s group, and one’s gender issues and identity. (Rohr 2011:4

  7. Splashpads, swings, and shade: parents' preferences for neighbourhood parks.

    Science.gov (United States)

    Tucker, Patricia; Gilliland, Jason; Irwin, Jennifer D

    2007-01-01

    Physical activity is a modifiable behaviour that can help curtail the increasing worldwide problem of childhood obesity. Appropriate recreational opportunities, including neighbourhood parks, are particularly important for promoting physical activity among children. Because children's use of parks is mainly under the influence of their parents, understanding parents' preferences is essential for creating the most inviting and usable park space to facilitate children's physical activity. Eighty-two intercept interviews were conducted with a heterogeneous sample of parents/guardians watching their children at neighbourhood parks in London, Ontario. Parents/guardians were asked questions about how often they frequent the park, whether it is the closest to their residence, and their likes/dislikes for the park. Strategies to ensure trustworthiness of the data were employed. Interviewees attended their park of choice between 1-7 times per week with the average being 2.5 times per week. Only 49% of respondents frequented the park closest to their starting destination (home or daycare facility), and the majority travelled more than 4 km to get to the park. For those who chose to travel a significant distance to attend their park of choice, park location was not as important as the amenities they desired. Parents' main reasons for choosing parks were: water attractions, shade, swings, and cleanliness. The current study provides useful insights on park use with potentially important implications for increasing physical activity among children. Incorporating parents' preferences into strategies for creating or modifying city parks will help to ensure that limited public resources are being targeted most effectively in support of children's physical activity.

  8. Nest-representable tolerances

    OpenAIRE

    Lipparini, Paolo

    2017-01-01

    We introduce the notion of a nest-representable tolerance and show that some results from our former paper "From congruence identities to tolerance identities" [CT] can be extended to this more general setting.

  9. DESENVOLVIMENTO DE UMA ESCALA EM SILICONA PARA TONS DE PELE HUMANA DEVELOPMENT OF A SILICONE SCALE FOR SHADES OF HUMAN SKIN

    Directory of Open Access Journals (Sweden)

    Ana Christina Claro NEVES

    1998-01-01

    Full Text Available O autor desenvolveu em silicona uma escala de tonalidades de pele humana. Foram confeccionados vinte e sete corpos-de-prova em silicona acética (Silastic 732 RTV, pigmentados com óxidos de ferro e dióxido de titânio. A quantidade de silicona acética manteve-se constante (dois gramas em todos os corpos-de-prova, e os pigmentos foram misturados a ela em várias proporções até a obtenção de vinte e sete diferentes tonalidades. Através da comparação da cor dos corpos-de-prova com a cor da pele de quarenta e um indivíduos, foram selecionados os cinco corpos-de-prova com as tonalidades que mais se igualavam à cor da pele dos pacientes, compondo, assim, um guia de tonalidades. Com a metodologia empregada, foi possível desenvolver uma escala de tonalidades de pele que poderá facilitar a definição do tom da pele do paciente quando da confecção de próteses faciais em silicona, permitindo economia de tempo e de material no momento da seleção da cor.The author developed a scale in silicone of shades of human skin. Twenty-seven samples were produced in acetic silicone (Silastic 732 RTV, pigmented with iron oxides and titanium dioxide. The amount of acetic silicone was kept constant (two grams in all of the samples, and the pigments were mixed to it in varying proportions, until twenty-seven different shades were obtained. By comparing the color of the samples with the skin color of forty-one individuals, five samples were selected of the shades that best matched a patient's color of skin to form a shade guide. With the methodology employed, it was possible to develop a shade guide that will facilitate a definition of a patient's skin color in producing facial prostheses in silicone, to afford economy in time and in material at time for selecting the color.

  10. Africa in SRTM 3-D, Anaglyph of Shaded Relief

    Science.gov (United States)

    2004-01-01

    This stereoscopic shaded relief image shows Africa's topography as measured by the Shuttle Radar Topography Mission (SRTM) in February 2000. Also shown are Madagascar, the Arabian Peninsula, and other adjacent regions. Previously, much of the topography here was not mapped in detail. Digital elevation data, such as provided by SRTM, are in high demand by scientists studying earthquakes, volcanism, and erosion patterns and for use in mapping and modeling hazards to human habitation. But the shape of Earth's surface affects nearly every natural process and human endeavor that occurs there, so elevation data are used in a wide range of applications. The image shown here is greatly reduced from the original data resolution, but still provides a good overview of the continent's landforms. It is best viewed while panning at full resolution while using image display software. The northern part of the continent consists of a system of basins and plateaus, with several volcanic uplands whose uplift has been matched by subsidence in the large surrounding basins. Many of these basins have been infilled with sand and gravel, creating the vast Saharan lands. The Atlas Mountains in the northwest were created by convergence of the African and Eurasian tectonic plates. The geography of the central latitudes of Africa is dominated by the Great Rift Valley, extending from Lake Nyasa to the Red Sea, and splitting into two arms to enclose an interior plateau and the nearly circular Lake Victoria, visible in the right center of the image. To the west lies the Congo Basin, a vast, shallow depression that rises to form an almost circular rim of highlands. Most of the southern part of the continent rests on a concave plateau comprising the Kalahari Basin and a mountainous fringe, skirted by a coastal plain that widens out in Mozambique in the southeast. Specific noteworthy features one may wish to explore in this scene include (1) the Richat Structure in Mauritania, a 'bull's eye

  11. Software fault tolerance

    OpenAIRE

    Kazinov, Tofik Hasanaga; Mostafa, Jalilian Shahrukh

    2009-01-01

    Because of our present inability to produce errorfree software, software fault tolerance is and will contiune to be an important consideration in software system. The root cause of software design errors in the complexity of the systems. This paper surveys various software fault tolerance techniquest and methodologies. They are two gpoups: Single version and Multi version software fault tolerance techniques. It is expected that software fault tolerance research will benefit from this research...

  12. The influence of varying layer thicknesses on the color predictability of two different composite layering concepts.

    Science.gov (United States)

    Khashayar, G; Dozic, A; Kleverlaan, C J; Feilzer, A J; Roeters, J

    2014-05-01

    Optical properties of teeth are mimicked by composite layering techniques by combining a relatively opaque layer (dentin) with more translucent layers (enamel). However, the replacing material cannot always optically imitate the tooth when applied in the same thickness as that of the natural tissues. The natural layering composite system is available in 2 concepts: (1) dentin (D) and enamel (E) have the same shade but with different translucencies; (2) D and E have different shades where E is always the same high translucent shade. The objective was to evaluate the influence of varying thicknesses of E and D composites on the overall color and on the translucency for both concepts. For each concept three composite brands were tested; Concept 1: Clearfil Photo Bright (Kuraray), Herculite XRV Ultra (Kerr), Venus Diamond (Heraeus Kulzer); Concept 2: Amaris (VOCO), CeramX Duo (DENTSPLY) and Point4 (Kerr). Two specimens of each shade (A1-A3) per composite were made of standardized thicknesses with a poly-acrylic mold and Teflon cover, making 36 specimens of wedge-like dimension. The L*a*b* values were measured three times against a white and black background (n=216). Student's t-tests revealed significant levels between the average ΔE* values of the 3 areas for each composite. Statistically significant differences (pconcepts. Concept 2 showed greater variations in ΔE* with increased thicknesses. Concept 2 composites are more sensitive to layer thickness changes, which implicates less predictability in a daily clinical routine. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  13. THE 3 - IN - 1 SKYLIGHT SHADING DEVICE FOR SURABAYA INDONESIA: AN ENERGY SAVING AND CONSIDERATIONS

    Directory of Open Access Journals (Sweden)

    Danny Santoso Mintorogo

    2004-01-01

    Full Text Available In terms of energy saving strategies and proper use of skylight modules in architectural buildings in the tropical climate, this paper will give evidence of how appropriate use of skylight modules installed on buildings in the tropical zone compared to the ones in the subtropical climate. In the tropical humid climate, Indonesia has received huge amount of global direct and diffuse radiations on horizontal roofs throughout the year, approximately 575 watts per square meter of radiation will impact on flat roofs or skylights on a sunny day in Surabaya city. Moreover, the hot season is longer, from mid May to mid December, than the wet season. Most of the commercial and institution buildings are equipped with Western skylight styles in Surabaya without any modifications. The three-in-one skylight device is the system that will control daylight, shade direct solar heat radiation, and collect solar hot water at the same time. The concept of the three-in-one shading device has three goals: first of all, it is to shade horizontal or tiled skylight on roof providing shading devices. Secondly, the series of circular cube as shading device will bounce and scatter the direct sunlight into the space below enhancing daylight patterns. Finally, while shading and bouncing direct sunlight, those series of circular shading water pipes would also collect the solar heat radiation getting hot water. Each system works nicely to block, to scatter, and to obtain the solar heat radiation for energy saving in green architecture and clean environmental living zones.

  14. Do shade-grown coffee plantations pose a disease risk for wild birds?

    Science.gov (United States)

    Hernandez, Sonia M; Peters, Valerie E; Weygandt, P Logan; Jimenez, Carlos; Villegas, Pedro; O'Connor, Barry; Yabsley, Michael J; Garcia, Maricarmen; Riblet, Sylva M; Carroll, C Ron

    2013-06-01

    Shade-grown coffee plantations are often promoted as a conservation strategy for wild birds. However, these agro-ecosystems are actively managed for food production, which may alter bird behaviors or interactions that could change bird health, compared to natural forest. To examine whether there is a difference between the health parameters of wild birds inhabiting shade-grown coffee plantations and natural forest, we evaluated birds in Costa Rica for (1) their general body condition, (2) antibodies to pathogens, (paramyxovirus and Mycoplasma spp.), and (3) the prevalence and diversity of endo-, ecto-, and hemoparasites. We measured exposure to Mycoplasma spp. and paramyxovirus because these are pathogens that could have been introduced with domestic poultry, one mechanism by which these landscapes could be detrimental to wild birds. We captured 1,561 birds representing 75 species. Although seasonal factors influenced body condition, we did not find bird general body condition to be different. A total of 556 birds of 31 species were tested for antibodies against paramyxovirus-1. Of these, five birds tested positive, four of which were from shade coffee. Out of 461 other tests for pathogens (for antibodies and nucleotide detection), none were positive. Pterolichus obtusus, the feather mite of chickens, was found on 15 birds representing two species and all were from shade-coffee plantations. Larvated eggs of Syngamus trachea, a nematode typically associated with chickens, were found in four birds captured in shade coffee and one captured in forest. For hemoparasites, a total of 1,121 blood smears from 68 bird species were examined, and only one species showed a higher prevalence of infection in shade coffee. Our results indicate that shade-coffee plantations do not pose a significant health risk to forest birds, but at least two groups of pathogens may deserve further attention: Haemoproteus spp. and the diversity and identity of endoparasites.

  15. Effect Of Shade Organic Materials And Varieties On Growth And Production Of Upland Rice

    Directory of Open Access Journals (Sweden)

    Jonatan Ginting

    2015-01-01

    Full Text Available Abstract There is a shade factor and low organic matter content of the soil is a problem that needs to be addressed in the development of upland rice cultivation as intercrops in the plantation area. Based on these considerations then one study that needs to be done is to conduct experiments on the effect of shade factor combined with the the provision of the organic material to the some varieties of upland rice that has been recommended nationally. The objective of experiment is to study the influence of shade organic materials and varieties on the growth and production of upland rice. This research using experimental design of Split - Split Plot Design with 3 treatment factors and 3 replications or blocks. The first factor is the treatment of shade with 3 levels shade percentage 0 20 and 40. The second factor is the dosage of organic material consists of 3 levels 0 g polybag 25 g polybag 50 g polybag and 75 g polybag. The third factor is the treatment of varieties consists of 4 types of upland rice varieties Si Kembiri Situ Patengggang Situ Bagendit and Tuwoti. The research results showed that the effect of shade on upland rice varieties decrease number of tillers number of panicles number of productive grains grain production per hill of uplnd rice plants and total sugar content of upland rice plants. Effect of organic matter increases number of panicles number of productive grains grain production per hill of upland rice plants and total sugar content of upland rice plants. It is known that the the variety of Situ Patenggang provides better growth and production compared with three other varieties Si Kembiri Situ Bagendit and Tuwoti in shaded conditions.

  16. Shading and sediment structure effects on stream metabolism resistance and resilience to infrequent droughts.

    Science.gov (United States)

    Zlatanović, Sanja; Fabian, Jenny; Premke, Katrin; Mutz, Michael

    2017-10-22

    Perennial, temperate, low-order streams are predicted to become intermittent as a result of irregular droughts caused by global warming and increased water demand. We hypothesize that stream metabolism changes caused by irregular droughts are linked to the shading and bed sediment structure of temperate streams. We set up 16 outdoor experimental streams with low or high shade conditions and streambeds either with alternating sorted patches of gravel and sand or homogeneous gravel-sand mix sediment structures. We assessed community respiration (CR), net ecosystem production (NEP) and periphyton biomass and structure (diatoms, green algae, cyanobacteria) in the course of 6weeks colonization, 6weeks desiccation, and 2.5weeks after rewetting. The heterotroph to autotroph (H:A) and fungi to bacteria (F:B) ratios in the microbial biofilm community were assessed at the end of the colonization and rewetting phases. Streams with different bed sediment structure were functionally similar; their metabolism under desiccation was controlled solely by light availability. During flow recession, all streams showed net heterotrophy. As desiccation progressed, NEP and CR decreased to zero. Desiccation altered the periphyton composition from predominantly diatoms to green algae and cyanobacteria, particularly in streams with low shade and mixed sediments. Rapid post-drought resilience of NEP was accompanied by high cyanobacteria and green algae growth in low shade, but poor total periphyton growth in high shade streams. Variable periphyton recovery was followed by increased H:A in relation to shading, and decreased F:B in relation to sediments structure. These shifts resulted in poor CR recovery compared to the colonization phase, suggesting a link between CR resilience and microbial composition changes. The links between drought effects, post-drought recovery, shading level, and streambed structure reveal the importance of low-order stream management under a changing climate and

  17. Effects of Luting Composites on the Resultant Colors of Ceramic Veneers to Intended Shade Tab.

    Science.gov (United States)

    Li, Qing

    2017-01-20

    To investigate the color differences of ceramic veneers and the intended shade tab, and evaluate the effects of luting composites on the resultant colors of ceramic veneers. Pressable leucite-reinforced feldspathic ceramic discs (IPS e.max), with nominal shade A3, were fabricated with thicknesses of 1.0 mm, 0.7 mm, and 0.5 mm (n = 10/ thickness). The ceramic specimens were cemented onto a composite background (shade Dentin) using a veneer adhesive system with five colors of luting composites (RelyX). The colors of the veneer (veneer/luting/background complexes) and corresponding shade tab (A3, Vitapan) were measured using a spectrophotometer, and subsequently converted to CIE L*a*b* values. Color differences (△E) between each complex and the shade tab were calculated and analyzed with two-way ANOVA. Tukey's multiple comparisons were used to evaluate the effects of luting composites on the △E values. The means of color differences between ceramic veneers and intended shade tab were 2.50 ± 0.38, 3.17 ± 0.48, and 3.84 ± 0.63 for the 1.0 mm, 0.7 mm, and 0.5 mm thicknesses, respectively. △E values were significantly affected by the veneer thickness and the luting composite color (p veneers to the intended shade tab was not achieved in the 0.7 mm and 0.5 mm veneer thicknesses, whichever colors of the luting composites were used. © 2017 by the American College of Prosthodontists.

  18. Shade tree diversity, cocoa pest damage, yield compensating inputs and farmers' net returns in West Africa.

    Directory of Open Access Journals (Sweden)

    Hervé Bertin Bisseleua Daghela

    Full Text Available Cocoa agroforests can significantly support biodiversity, yet intensification of farming practices is degrading agroforestry habitats and compromising ecosystem services such as biological pest control. Effective conservation strategies depend on the type of relationship between agricultural matrix, biodiversity and ecosystem services, but to date the shape of this relationship is unknown. We linked shade index calculated from eight vegetation variables, with insect pests and beneficial insects (ants, wasps and spiders in 20 cocoa agroforests differing in woody and herbaceous vegetation diversity. We measured herbivory and predatory rates, and quantified resulting increases in cocoa yield and net returns. We found that number of spider webs and wasp nests significantly decreased with increasing density of exotic shade tree species. Greater species richness of native shade tree species was associated with a higher number of wasp nests and spider webs while species richness of understory plants did not have a strong impact on these beneficial species. Species richness of ants, wasp nests and spider webs peaked at higher levels of plant species richness. The number of herbivore species (mirid bugs and cocoa pod borers and the rate of herbivory on cocoa pods decreased with increasing shade index. Shade index was negatively related to yield, with yield significantly higher at shade and herb covers<50%. However, higher inputs in the cocoa farms do not necessarily result in a higher net return. In conclusion, our study shows the importance of a diverse shade canopy in reducing damage caused by cocoa pests. It also highlights the importance of conservation initiatives in tropical agroforestry landscapes.

  19. [A comparison of color space of Vitapan 3D-Master shade guides to nature teeth from Nanjing population].

    Science.gov (United States)

    Zhou, Xiao-Lu; Luo, Xiao-Ping; Liu, Xia

    2009-04-01

    To study the fitness of color dimension between Vitapan 3D-Master shade guides and nature teeth. 2,159 nature teeth from Nanjing population and Vitapan 3D-Master shade guides were analyzed by dental chromameter ShadeEye NCC on CIE L*a*b* color system. 1) The color dimension of natural teeth displayed a broader range than those from Vitapan 3D-Master shade guides. Comparing with incisor group, canine-premolar group had better fitness with Vitapan 3D-Master shade guides. 2) In color space, incisor values a* shifted toward green (-a*), while the shade guide values a* located toward red (+a*). The shade guide lacked tabs of values L* 71-78 and a* -1.5-(-)0.2 for natural incisor. 3) According to the perceptibility threshold AE*ab3D-Master shade guides was 33% in incisor group and 50% in canine-premolar group. Vitapan 3D-Master shade guides had inferior match with nature teeth from Nanjing population, especially in incisor.

  20. Implementation of window shading models into dynamic whole-building simulation

    Science.gov (United States)

    Lomanowski, Bartosz Aleksander

    An important consideration in energy efficient building design is the management of solar gain, as it is the largest and most variable gain in a building. The design of buildings with highly glazed facades, as well as decreased energy transfer rates through better insulated and tighter envelopes are causing interior spaces to become highly sensitive to solar gain. Shading devices such as operable slat-type louver blinds are very effective in controlling solar gain, yet their impact on peak cooing loads and annual energy consumption is poorly understood. With the ever-increasing role of building energy simulation tools in the design of energy efficient buildings, there is a clear need to model windows with shading devices to assess their impact on building performance. Recent efforts at the University of Waterloo's Advanced Glazing Systems Laboratory (AGSL) in window shading research have produced a set of flexible shading models. These models were developed with emphasis on generality and computational efficiency, ideally suited for integration into building simulation. The objective of the current research is to develop a complex fenestration facility within a general purpose integrated building simulation software tool, ESP-r, using the AGSL shading models. The strategy for implementation of the AGSL shading models is the addition of a new multi-layer construction within ESP-r, the Complex Fenestration Construction (CFC). The CFC is based on the standard ESP-r multi-layer nodal structure and finite control volume numerical model, with additional measures for coping with the complexities that arise in the solar, convective and radiant exchanges between glazing/shading layers, the interior zone and exterior surroundings. The CFC algorithms process the solar, convective and radiant properties of the glazing/shading system at each time-step, making it possible to add control (e.g., changing the slat angle of a slat-type blind) at the time-step level. Thermal

  1. Prevalence of Colour Vision Anomalies Amongst Dental Professionals and its Effect on Shade Matching of Teeth

    Science.gov (United States)

    Maini, Anuj Paul; Wangoo, Anuj; Singh, Sukhman; Mehar, Damanpreet Kaur

    2017-01-01

    Abstract Introduction The success of a restoration is dependent on accurate shade matching of teeth leading to studies evaluating the factors affecting the perception of shades. Colour vision anomalies including colour blindness have been found to exist in the population and it has been thought to be a potential factor affecting the colour perception ability. Aim The present study was done to evaluate the prevalence of colour vision anomalies and its effect on matching of shades of teeth. Materials and Methods A total of 147 dental professionals were randomly selected for the study and were first tested for visual acuity using the Snellen’s Eye Chart so as to carry on the study with only those operators who had a vision of 6/6. Then, the Ishihara’s colour charts were used to test the operators for colour vision handicap. In the last stage of the study, test for accuracy of shade selection was done using the Vitapan Classical shade guide. The shade guide tabs were covered to avoid bias. Percentage was used to calculate the prevalence of colour vision handicap and its effect on matching of shades of teeth as compared to normal vision, which was evaluated using Chi square test. Results Nineteen operators had colour vision anomalies out of hundred operators and only two operators presented with colour blindness. Colour vision anomaly was more prevalent than colour blindness and it was also found that it was more prevalent in males than females. The difference between the accuracy of shade matching between the operators with normal vision and colour vision defect and operators with normal vision and colour blindness was statistically not significant. Conclusion Colour blindness and colour vision handicap are rare conditions, with the latter being more common in the population. According to our study, it was concluded that no statistically significant difference existed amongst the operators with normal vision and colour vision anomaly or operators with normal vision

  2. Cyclic Loading Effect on Color Stability of Unshaded versus Shaded Zirconia.

    Science.gov (United States)

    Spyropoulou, Panagiota-Eirini; Kamposiora, Phophi; Eliades, George; Papavasiliou, George; Razzoog, Michael E; Bayne, Stephen C

    2016-01-01

    Shaded versions of dental zirconia may improve initial color matching to teeth, but might change color with cyclic mechanical loading. The purpose of this study was to measure the color of unshaded and shaded zirconia dental ceramic before and after cyclic mechanical loading and calculate color differences (ΔE). Disk-shaped specimens (N = 30, Nobel Procera, 0.8 mm thick, 12 mm diameter) of unshaded or shaded zirconia (intrinsically shaded by small oxide modifications) were fabricated by the Nobel Biocare using standard CAD-CAM processing. Milled surfaces were polished. CIE L*a*b* values were measured (Konica Minolta spectrophotometer) before and after mechanical cycling (custom modified Leinfelder test machine, biaxial flexure loading, load = 80 N × 500,000 cycles, dry), and L*a*b* individual differences and ΔE color differences were calculated and compared (ANOVA, p L*a*b* values for the unshaded group before (U1 = 86.165, -0.887, 0.372) and after (U2 = 84.860, -0.805, 0.097) cyclic loading were compared to the shaded group before (S1 = 75.281, -0.679, 23.251) and after (S2 = 74.961, -1.233, 22.439) cyclic loading. All color variables for both unshaded and shaded groups were significantly different between before and after cyclic loading (p < .004) except for the L* value of the shaded group. The ΔE for unshaded (1.441 ± 0.495) versus shaded (1.252 ± 0.363) were statistically different but clinically the change would not be detectable at this point. The color of the unshaded and shaded zirconia specimens was influenced by cyclic loading (p < 0.05). Color changes were detectable but small at levels up to 500,000 cycles, and remained clinically acceptable at that point. It is important to acknowledge any possible color changes that might occur in zirconia restorations, especially in the esthetic zone. Minor color changes that are individually imperceptible to the human eye within different restorative components

  3. Mechanical tolerance stackup and analysis

    CERN Document Server

    Fischer, Bryan R

    2004-01-01

    BackgroundDimensioning and TolerancingTolerance Format and Decimal PlacesConverting Plus/Minus Dimensions and Tolerances into Equal Bilaterally Toleranced DimensionsVariation and Sources of VariationTolerance AnalysisWorst-case Tolerance StackupsStatistical Tolerance StackupsGeometric Dimensioning and Tolerancing (GD&T)Converting Plus/Minus Tolerancing to Positional Tolerancing and Projected Tolerance ZonesDiametral and Radial Tolerance StackupsSpecifying Material Condition Modifiers and Their Effect on Tolerance Stackups The Tolerance Stackup SketchThe Tolerance Stackup Report FormTolerance S

  4. Susceptibility to UV damage in Impatiens capensis (Balsaminaceae): testing for opportunity costs to shade-avoidance and population differentiation.

    Science.gov (United States)

    Dixon, P; Weinig, C; Schmitt, J

    2001-08-01

    Plastic increases in leaf secondary compounds may be an adaptive strategy that reduces the damaging effects of high-energy, ultraviolet radiation (UV). Here, we examine (1) the relationship between fitness and anthocyanin and flavonoid concentrations in experimental, UV environments, (2) the effects of UV on Impatiens capensis plants derived from woodland and clearing sites, and (3) whether susceptibility to UV damage is reduced by exposure to high ratios of red : far-red wavelengths (R : FR), which also stimulate the production of leaf compounds. Seedlings from each site were exposed to either high R : FR typical of sunlight or low R : FR characteristic of foliar shade, after which plants were moved into ambient UV or UV-removal treatments. Ultraviolet radiation stimulated the production of anthocyanins and flavonoids. However, higher anthocyanin concentrations were associated with lower biomass in the UV environment. Relative to the clearing population, reproductive output of the woodland population was more detrimentally affected by exposure to UV, despite its higher concentration of anthocyanins. Increased anthocyanin production may therefore be a stress response rather than an adaptive one. The greater tolerance of the clearing population to UV suggests that populations with an evolutionary history of UV exposure evolve mechanisms to limit damage. The R : FR pretreatments did not influence susceptibility to UV damage.

  5. A study on reproducing silicone shade guide for maxillofacial prostheses matching Indian skin color.

    Science.gov (United States)

    Guttal, Satyabodh S; Patil, Narendra P; Nadiger, Ramesh K; Kulkarni, Reshma

    2008-01-01

    The value and success of a well-fitting and anatomically correct prosthesis are compromised if the color does not match the adjoining tissues. The use of powder colors to help develop a simplified silicone shade guide to aid in the fabrication of silicone facial prostheses for Indian patients has been described here. Ten powder pigments were used to fabricate the silicone samples for three different subjects having light, medium and dark complexions who were separated into three groups depending on the value of their shades. Four-step wedge silicone samples with thickness variations of 1, 2, 4 and 6mm were fabricated. Visual assessment of the samples was done by four evaluators to check the agreement of color match. Data was statistically analyzed using kappa coefficients. The kappa values were found to be 0.09-0.44 for a light skin tone, -0.11 to 0.77 for medium skin and 0.44 to 0.85 for dark skin tones. This study showed that the samples of dark skin tone matched the skin tone well and showed a statistically good agreement. To further test the validity of these shade guides, facial silicone veneers were fabricated for three patients having light, medium and dark complexion. The color matching showed satisfactory results. The silicone veneers matched the skin color of all three patients. Hence, this shade guide will help clinicians to obtain a good intrinsic shade and minimize extrinsic coloration.

  6. Tracking the global maximum power point of PV arrays under partial shading conditions

    Science.gov (United States)

    Fennich, Meryem

    This thesis presents the theoretical and simulation studies of the global maximum power point tracking (MPPT) for photovoltaic systems under partial shading. The main goal is to track the maximum power point of the photovoltaic module so that the maximum possible power can be extracted from the photovoltaic panels. When several panels are connected in series with some of them shaded partially either due to clouds or shadows from neighboring buildings, several local maxima appear in the power vs. voltage curve. A power increment based MPPT algorithm is effective in identifying the global maximum from the several local maxima. Several existing MPPT algorithms are explored and the state-of-the-art power increment method is simulated and tested for various partial shading conditions. The current-voltage and power-voltage characteristics of the PV model are studied under different partial shading conditions, along with five different cases demonstrating how the MPPT algorithm performs when shading switches from one state to another. Each case is supplemented with simulation results. The method of tracking the Global MPP is based on controlling the DC-DC converter connected to the output of the PV array. A complete system simulation including the PV array, the direct current to direct current (DC-DC) converter and the MPPT is presented and tested using MATLAB software. The simulation results show that the MPPT algorithm works very well with the buck converter, while the boost converter needs further changes and implementation.

  7. [A preliminary study on shade matching ability of dental professionals with different background].

    Science.gov (United States)

    Zhu, Guang-yu; Shan, Jun-ling; Kuang, Hai; Xu, Sheng; Luo, Li

    2014-06-01

    To investigate the difference of shade matching ability of dental professionals with different educational background using toothguide training box (TTB), and provide information for medical esthetics course in dental school. Sixty subjects including 20 dental students, 20 prosthodontics technical students and 20 prosthodontics technicians without color blindness were enrolled in this study. Each participant was asked to match 15 standard shade tabs which have been randomly chosen from Vita 3D-Master shade guide. SPSS 17.0 software package was used for data analysis. The scores of dental students, prosthodontics technical students and dental prosthodontics technicians were 834.04±51.66, 859.40±53.31and 888.36±48.54, respectively. There was no significant difference in the sum number of accurate shade matching compared between dental students and prosthodontics technical students (P>0.05), but there was significant difference between dental prosthodontics technicians, prosthodontics technical students (P<0.05), and dental students (P<0.01). The score of shade matching is significantly different among dental professionals with different background using TTB.

  8. Regulation of Black Pepper Inflorescence Quantity by Shading at Different Growth Stages.

    Science.gov (United States)

    Zu, Chao; Wu, Guiping; Li, Zhigang; Yang, Jianfeng; Wang, Can; Yu, Huan; Wu, Huasong

    2016-07-01

    Black pepper is a perennial plant that can bloom throughout the year. It is generally expected that pepper inflorescence quantity could be minimized at the nonfull-bloom stage. The objective of this study was to find an appropriate shading measure that could inhibit blooming at other growing stages except the full-bloom stage and did not cause any reduction in pepper yield and quality. In this study, pepper trees were shaded up to 15%, 30%, 60% and 75%, respectively, and the inflorescence quantity, photosynthetic characteristics, pepper yield and quality traits were investigated at every growing stage. The results showed that the effect of shading on pepper yield decreased as time progressed. Shading treatment did not alter the composition of piperine and volatile oil, but reduced the moisture content. Based on the correlation between photosynthetic parameter and inflorescence number, the appropriate shading intensities for regulating inflorescence quantity at different phenological stages were determined. Moreover, it was found that the regulation of inflorescence quantity could be achieved by controlling leaf temperature during recovery to filling period. This research outcome also will give us some guidelines to develop other management strategies that control leaf temperature and regulate inflorescence quantity to consequently improve pepper yield. © 2016 The American Society of Photobiology.

  9. Different levels of shade on population of grasshoppers and its oviposition preference on heliconias

    Directory of Open Access Journals (Sweden)

    Ana Cristina Bittar

    2018-02-01

    Full Text Available ABSTRACT: Grasshoppers of the families Acrididae and Romaleidae (Orthoptera are among the insects that defoliate heliconias and have been gaining status as pests of commercial crops of these plants in Brazil. The objectives of the present study were to identify the grasshopper defoliating heliconias in the municipality of Santo Antônio de Pádua, RJ (Brazil, to evaluate the effect of different levels of shade on the population of this grasshopper and the production parameters of heliconias, and to determine if this grasshopper has an oviposition preference among the heliconias evaluated. The experiment was in a completely randomized block design, in subdivided plots (four levels of shade in the plot, 0%, 30%, 50% and 80%, and four species of Heliconia: H. psittacorum, H. stricta, H. wagneriana and H. psittacorum x H. spathocircinata ‘Golden Torch’ in the subplot, with four replications. The grasshopper was identified as Cornops frenatum frenatum (Acrididae. An increase in shade resulted in a decrease in the number of oviposition holes from the grasshopper and the number of lateral buds. Shade did not influence the number of C. f. frenatum nymphs and adults and the number of flower stems. H. wagneriana was the most preferred species for oviposition by C. f. frenatum. Results suggested using screens to shade heliconia plants can help control C. f. frenatum populations, however, the light requirements of the heliconias should be considered to guarantee productivity.

  10. A study on reproducing silicone shade guide for maxillofacial prostheses matching Indian skin color

    Directory of Open Access Journals (Sweden)

    Guttal Satyabodh

    2008-01-01

    Full Text Available Aim: The value and success of a well-fitting and anatomically correct prosthesis are compromised if the color does not match the adjoining tissues. The use of powder colors to help develop a simplified silicone shade guide to aid in the fabrication of silicone facial prostheses for Indian patients has been described here. Materials and Methods: Ten powder pigments were used to fabricate the silicone samples for three different subjects having light, medium and dark complexions who were separated into three groups depending on the value of their shades. Four-step wedge silicone samples with thickness variations of 1, 2, 4 and 6mm were fabricated. Visual assessment of the samples was done by four evaluators to check the agreement of color match. Data was statistically analyzed using kappa coefficients. Results: The kappa values were found to be 0.09-0.44 for a light skin tone, -0.11 to 0.77 for medium skin and 0.44 to 0.85 for dark skin tones. This study showed that the samples of dark skin tone matched the skin tone well and showed a statistically good agreement. To further test the validity of these shade guides, facial silicone veneers were fabricated for three patients having light, medium and dark complexion. The color matching showed satisfactory results. Conclusion: The silicone veneers matched the skin color of all three patients. Hence, this shade guide will help clinicians to obtain a good intrinsic shade and minimize extrinsic coloration.

  11. Field performance of exterior solar shadings for residential windows : summer results

    Energy Technology Data Exchange (ETDEWEB)

    Laouadi, A.; Galasiu, A.D.; Swinton, M.C.; Armstrong, M.M.; Szadkowski, F. [National Research Council, Ottawa, ON (Canada). Inst. for Research in Construction

    2009-07-01

    It is estimated that the energy demand for heating and cooling accounts for approximately 60 per cent of the total energy use of an average Canadian home. On summer afternoons, many populated areas experience a peak demand for electricity even though the demand for cooling energy is much lower than the demand for heating. Exterior window shading devices offer an opportunity to reduce solar overheating in summer and heat losses in winter, and to improve the thermal comfort of the house occupants when seated near windows, compared to interior shadings. A project has been initiated to develop guidelines for effective exterior, mid-pane and interior shading devices in Canadian residences. This paper presented the results of three weeks of summer field measurements of exterior insulating rollshutters installed on the windows of a typical two-storey detached house compared to typical interior Venetian blinds installed in an identical neighbouring house. The paper described the objectives of the study and provided a description of the test-site and shading devices. The paper also described the measurement setup; air temperature and relative humidity measurements; electrical energy and gas use; solar radiation; thermal and air measurements near windows; and window and shading temperature. It was concluded that the daily total electric energy utilized by the air-conditioning unit and the circulation fan in the house equipped with rollshutters was 12 to 37 per cent lower than in the house equipped with interior blinds. 10 refs., 20 figs.

  12. Comparative evaluation of performance measures for shading correction in time-lapse fluorescence microscopy.

    Science.gov (United States)

    Liu, L; Kan, A; Leckie, C; Hodgkin, P D

    2017-04-01

    Time-lapse fluorescence microscopy is a valuable technology in cell biology, but it suffers from the inherent problem of intensity inhomogeneity due to uneven illumination or camera nonlinearity, known as shading artefacts. This will lead to inaccurate estimates of single-cell features such as average and total intensity. Numerous shading correction methods have been proposed to remove this effect. In order to compare the performance of different methods, many quantitative performance measures have been developed. However, there is little discussion about which performance measure should be generally applied for evaluation on real data, where the ground truth is absent. In this paper, the state-of-the-art shading correction methods and performance evaluation methods are reviewed. We implement 10 popular shading correction methods on two artificial datasets and four real ones. In order to make an objective comparison between those methods, we employ a number of quantitative performance measures. Extensive validation demonstrates that the coefficient of joint variation (CJV) is the most applicable measure in time-lapse fluorescence images. Based on this measure, we have proposed a novel shading correction method that performs better compared to well-established methods for a range of real data tested. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

  13. Estimation of Areal Mean Rainfall in Remote Areas Using B-SHADE Model

    Directory of Open Access Journals (Sweden)

    Tao Zhang

    2016-01-01

    Full Text Available This study presented a method to estimate areal mean rainfall (AMR using a Biased Sentinel Hospital Based Area Disease Estimation (B-SHADE model, together with biased rain gauge observations and Tropical Rainfall Measuring Mission (TRMM data, for remote areas with a sparse and uneven distribution of rain gauges. Based on the B-SHADE model, the best linear unbiased estimation of AMR could be obtained. A case study was conducted for the Three-River Headwaters region in the Tibetan Plateau of China, and its performance was compared with traditional methods. The results indicated that B-SHADE obtained the least estimation biases, with a mean error and root mean square error of −0.63 and 3.48 mm, respectively. For the traditional methods including arithmetic average, Thiessen polygon, and ordinary kriging, the mean errors were 7.11, −1.43, and 2.89 mm, which were up to 1027.1%, 127.0%, and 358.3%, respectively, greater than for the B-SHADE model. The root mean square errors were 10.31, 4.02, and 6.27 mm, which were up to 196.1%, 15.5%, and 80.0%, respectively, higher than for the B-SHADE model. The proposed technique can be used to extend the AMR record to the presatellite observation period, when only the gauge data are available.

  14. PRELIMINARY STUDY OF SEAWEED DRYING UNDER A SHADE AND IN A NATURAL DRAFT SOLAR DRYER

    Directory of Open Access Journals (Sweden)

    Hooi-Kim Phang

    2014-12-01

    Full Text Available A solar dryer was designed to study the seaweed drying process under natural convection and compared to a shade drying process. A dewatering pre-treatment process was initially applied to enhance drying process for both methods. The initial weight of seaweed before pre-treatment and after pre-treatment was recorded and the seaweed was then introduced into the solar drying system and shade drying system. The air temperature and relative humidity inside the solar dryer and surrounding were recorded during experiment. A representative sample on each tray was taken for final moisture content determination where the difference of seaweed weight less than 5% for subsequent measurement. The average weight loss of seaweed from pre-treatment was about 54%. The final moisture content of seaweed for solar drying was in the range of 24-61% (d.b. and for shade drying was in the range of 40-48% (d.b. with a standard deviation of final moisture content of 20.45% for solar drying and 3.78% for shade drying. The total time for solar drying inclusive of pre-treatment was 6 days and shade drying was 9 days. The drying kinetics of each method was modeled and the results of this study will be utilized to enhance the design and operations of seaweed solar dryers.

  15. A Psychoacoustic Investigation on the Effect of External Shading Devices on Building Facades

    Directory of Open Access Journals (Sweden)

    Nicolò Zuccherini Martello

    2016-12-01

    Full Text Available Due to energetic and natural lighting factors, building facades often present external shading devices, but the acoustic properties of such devices have not yet been well studied. This study was carried out using a full-scale model of a portion of a shading device, in a semi-anechoic chamber, using traditional and sound absorbing louvres. The psychoacoustic effects produced by the shading system were evaluated through comparisons between averaged values of loudness, roughness and sharpness levels, as well as sound pressure levels as reference. Results highlighted that the sound absorbing shading device offers good attenuation in terms of loudness, roughness and sound pressure level, with a small reduction in sharpness. The traditional shading system studied does not efficiently reduce the analysed parameters, or even worsens the situation. Several analyses of variance were carried out, one for each situation studied. The sound source position and the louvres’ tilt angle both produce statistically significant effects on almost all of the variations of the parameters studied. The analyses of the partial eta squared factors highlighted that source position and louvre tilt angle affect the variations of the parameters studied to a different degree in respect of the two types of louvres.

  16. Environmental tolerances of rare and common mangroves along light and salinity gradients.

    Science.gov (United States)

    Dangremond, Emily M; Feller, Ilka C; Sousa, Wayne P

    2015-12-01

    Although mangroves possess a variety of morphological and physiological adaptations for life in a stressful habitat, interspecific differences in survival and growth under different environmental conditions can shape their local and geographic distributions. Soil salinity and light are known to affect mangrove performance, often in an interactive fashion. It has also been hypothesized that mangroves are intrinsically shade intolerant due to the high physiological cost of coping with saline flooded soils. To evaluate the relationship between stress tolerance and species distributions, we compared responses of seedlings of three widespread mangrove species and one narrow endemic mangrove species in a factorial array of light levels and soil salinities in an outdoor laboratory experiment. The more narrowly distributed species was expected to exhibit a lower tolerance of potentially stressful conditions. Two of the widespread species, Avicennia germinans and Lumnitzera racemosa, survived and grew well at low-medium salinity, regardless of light level, but performed poorly at high salinity, particularly under high light. The third widespread species, Rhizophora mangle, responded less to variation in light and salinity. However, at high salinity, its relative growth rate was low at every light level and none of these plants flushed leaves. As predicted, the rare species, Pelliciera rhizophorae, was the most sensitive to environmental stressors, suffering especially high mortality and reduced growth and quantum yield under the combined conditions of high light and medium-high salinity. That it only thrives under shaded conditions represents an important exception to the prevailing belief that halophytes are intrinsically constrained to be shade intolerant.

  17. Fault tolerant control for uncertain systems with parametric faults

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2006-01-01

    A fault tolerant control (FTC) architecture based on active fault diagnosis (AFD) and the YJBK (Youla, Jarb, Bongiorno and Kucera)parameterization is applied in this paper. Based on the FTC architecture, fault tolerant control of uncertain systems with slowly varying parametric faults...

  18. Differential radiologic diagnosis of the spherical shades found in the maxillary sinus

    Energy Technology Data Exchange (ETDEWEB)

    Vorob' ev, Yu.I.; Litvakovskaya, G.A.; Bogdashevskaya, V.B.; Buzanov, V.A. (Moskovskij Meditsinskij Stomatologicheskij Inst. (USSR))

    Data obtained during clinical and radiologic examination of 203 patients have been analysed. It was found that the error percentage in diagnosis of the spherical shades in the maxillary sinuses reaches 22% according to plain radiography of the nasal sinuses. A radiologic sympton of the spherical shade in the lumen of the maxillary sinus may be detected either in bening processes (retentive and odontogenic cysts, bening tumors, fibrous dysplasia of the jaws, etc.), or in malignant tumors, originating from the alveolar process area and the hard palate. Some radiologic signs of the most common diseases, accompanied by the sherical shade sympton in the lumen of the maxillary sinus, are described. A verification of both localization and nature of pathologic process in the maxillary sinus is carried out by means of multiposition craniography and various modifications of the stratifying X-ray examination.

  19. Shade matching quality among dental students using visual and instrumental methods.

    Science.gov (United States)

    Bahannan, Salma A

    2014-01-01

    Study aims were to compare shade matching quality between visual and machine-aided shade selection among dental students and to evaluate the effect of experience and gender. A total of 204 undergraduates and interns participated. They were briefed about colour matching using a visual method with a Vita-3D Master system and a spectrophotometer. Participants with colour vision deficiency were excluded. Six maxillary anterior teeth of a maxillary blue stone cast were replaced with six maxillary artificial teeth. Participants selected the best shade match using each method. A daylight illuminator with the GTI mini-matcher colour viewing system was used during the test. The results were statistically analysed with SPSS version 19 with 95% confidence intervals. Frequencies and Chi-square tests were used to analyse the data, at α=0.05 and with Pdental students. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. The effect of chemical disinfectants on the color of a porcelain shade guide.

    Science.gov (United States)

    ArRejaie, Aws S

    2014-07-01

    To evaluate the effect of long term utilization of chemical disinfectants on the color of porcelain shade guides. three chemical disinfectants were used in this study: Minuten spray, Lysol ICQuaternary Disinfectant Cleaner (QDC), and Lysol IC Ready to Use Disinfectant Cleaner (RDC). Simulation of disinfecting cycles for one year, two years, and three years were done on Vita 3D master shade guide. Color differences were determined by visual inspection and analyzing ΔE. ΔE values were significantly below the perceptible (ΔE=1) and the clinically acceptable (ΔE=3.7) thresholds. Simulated utilization of Minuten Spray, Lysol IC (QDC), and Lysol (RDC) disinfectants for up to three years didn't cause a clinically significant difference in the color of VITA Toothguide 3D-Master Shade Guide.

  1. SHADING AND NITROGEN FERTILIZATION ON SOIL ATTRIBUTES IN A PASTURE OF BRACHIARIA BRIZANTHA CV. MARANDU

    Directory of Open Access Journals (Sweden)

    Guilherme Lanna Reis

    2011-12-01

    Full Text Available This study assessed the influence of nitrogen fertilization and artificial shade on the attributes of soil and forage in a pasture of Brachiaria brizantha cv Marandu (BBM. The experiment was conducted at Fazenda Águas Formosas in Caeté, Minas Gerais State, Brazil, 19º47’39’’S,43º36’77’’W, altitude 1000 m. The soil is a Red latosol by the Brazilian soil classification (Typic Acrustox - USDA classification. BBM was subjected to four levels of fertilization (0, 50, 70 and 100 kg N per hectare per application and four levels of shading (0, 47, 53 and 66% through a nylon mesh. Shading reduced the mineralization of organic matter, affecting the lower availability of complexed nutrients. N application favored the exportation of most nutrients assessed. Nutrient content tended to decrease with depth.

  2. The Relationship between On-Farm Shade Trees and Cocoa Yields in Ghana

    DEFF Research Database (Denmark)

    Asare, Richard

    Cocoa (Theobroma cacao L.) is a crop that is widely cultivated across West Africa with Côte d’Ivoire, Cameroon, Ghana and Nigeria contributing about 70% of the global production. In Ghana cocoa contributes significantly to the national economy as over 20% of the world’s cocoa production comes from...... the country, making it the world’s second largest producer with an annual production level of over 700,000 metric tons, and an estimated cultivation area of ca. 1.6 million ha. Cocoa is mostly cultivated by smallholder farmers either as a monocrop or in association with other food crops, tree crops and under...... the cover of shade trees – cocoa agroforestry. This thesis hypothesizes that canopy cover of shade trees in low input (low-to-no fertilizer application) cocoa growing systems can contribute to cocoa yield improvements. The main theme deals with shade trees diversity and its effects on cocoa production...

  3. Evaluation of accuracy of shade selection using two spectrophotometer systems: Vita Easyshade and Degudent Shadepilot.

    Science.gov (United States)

    Kalantari, Mohammad Hassan; Ghoraishian, Seyed Ahmad; Mohaghegh, Mina

    2017-01-01

    The aim of this in vitro study was to evaluate the accuracy of shade matching using two spectrophotometric devices. Thirteen patients who require a full coverage restoration for one of their maxillary central incisors were selected while the adjacent central incisor was intact. 3 same frameworks were constructed for each tooth using computer-aided design and computer-aided manufacturing technology. Shade matching was performed using Vita Easyshade spectrophotometer, Shadepilot spectrophotometer, and Vitapan classical shade guide for the first, second, and third crown subsequently. After application, firing, and glazing of the porcelain, the color was evaluated and scored by five inspectors. Both spectrophotometric systems showed significantly better results than visual method (P spectrophotometers (P Spectrophotometers are a good substitute for visual color selection methods.

  4. [Effect of ceramic thickness and resin cement shades on final color of heat-pressed ceramic veneers].

    Science.gov (United States)

    Ren, D F; Zhan, K R; Chen, X D; Xing, W Z

    2017-02-09

    Objective: To analyze the effect of ceramic materials thickness and resin cement shades on the final color of ceramic veneers in the discolored teeth, and to investigate the color agreement of try-in pastes to the corresponding resin cements. Methods: Sixty artificial maxillary central incisor teeth (C2 shade) were used to simulate the natural discolored teeth and prepared according to veneer tooth preparation protocol. Veneers of different thickness in the body region (0.50 and 0.75 mm) were fabricated using ceramic materials (LT A2 shade, IPS e.max Press). The ceramic veneer specimens were bonded to the artificial teeth using the 6 shades of resin cements (Variolink Veneer: shades of LV-3, LV-2, HV+3; RelyX™ Veneer: shades of TR, A3, WO) ( n= 5). A clinical spectrophotometer was used to measure the color parameters of ceramic veneers at the cervical, body and incisal regions. Color changes of veneers before and after cementation were calculated and registered as ΔE1, and the changes between try-in paste and the corresponding resin cements were registered as ΔE2. Results: Three-way ANOVA indicated that ΔE1 and ΔE2 values were significantly affected by the ceramic thickness, resin cement shades and measuring regions ( Pveneers were cemented with resin cements in shades of HV+3 and WO. The ΔE2 values of six shades ranged from 0.60-2.56. The shades of HV+3, WO and A3 resin cements were more than 1.60. Conclusions: Different thickness of ceramic materials, resin cement shades and measuring regions could affect the final color of ceramic veneers. The color differences of some resin cements and corresponding try-in pastes might be observed in clinical practice.

  5. Modifications on leaf anatomy of Coffea arabica caused by shade of pigeonpea (Cajanus cajan

    Directory of Open Access Journals (Sweden)

    Heverly Morais

    2004-11-01

    Full Text Available Modifications on leaf anatomy in Coffea arabica shaded with pigeonpea (Cajanus cajan, compared to cultivation under full sun, were assessed. The leaves fully exposed to sunlight presented thicker cuticles and cellular walls, narrower epidermis cells, palisade parenchyma with longer cells, thicker lacunar parenchyma, fewer intercellular spaces and a larger stomata number. Leaves under dense shade presented a narrower cuticle and cellular wall; a mesophyll with smaller volume, but with larger intercellular spaces; and epidermis with thicker cells and a smaller stomata amount, surrounded by subsidiary cells of smaller dimensions. Plants grown under full sunlight presented higher values of net photosynthesis. The results evidenced that the species C. arabica has a wide range of phenotypic adaptation to changes in the radiation intensity.Adaptações de plantas da mesma espécie aos diferentes habitats, constituem a base da diferenciação entre folhas a pleno sol e folhas sob sombra e estão associadas a características anatômicas distintas. Para caracterizar tais mudanças em cafeeiros cultivados sob sombra de guandu (Cajanus cajan e a pleno sol, em Londrina, PR, foram realizadas avaliações de modificações ocorridas na anatomia foliar. As estruturas internas avaliadas foram: parede celular e cutícula; epiderme; mesofilo (parênquima paliçádico, parênquima lacunoso e espaços intercelulares e estômatos. Para todas as variáveis avaliadas observaram-se diferenças anatômicas entre folhas expostas ao sol e à sombra. As folhas expostas ao sol apresentaram cutículas e paredes celulares mais espessas, células da epiderme mais estreitas, parênquima paliçádico com células mais alongadas, parênquima lacunoso espesso e com poucos espaços intercelulares e maior número de estômatos. Folhas sob condições de denso sombreamento apresentam menor espessamento da cutícula e da parede celular; mesofilos com menores volumes, porém com

  6. Behavioral ecology of Heteragrion consors Hagen (Odonata, Megapodagrionidae: a shade-seek Atlantic forest damselfly

    Directory of Open Access Journals (Sweden)

    Geovanni Ribeiro Loiola

    2011-09-01

    Full Text Available Behavioral ecology of Heteragrion consors Hagen (Odonata: Megapodagrionidae: a shade-seek Atlantic forest damselfly. The intensity of the inter and intra-sexual selection can affect male behavioral traits as territorial fidelity and aggressiveness allowing the existence of different strategies. However, its differential success could be affected by environmental - as the diel variation in temperature - and physiological constrains - as the variation in thermoregulatory abilities. In this context, we present a behavioral analysis of Heteragrion consors (Zygoptera, Megapodagrionidae trying to characterize its mating system, diel activity pattern, temporal budget, territoriality and reproductive biology. These data were obtained based on field observations using the focal individual method and mark-recapture techniques in 120 m of a shaded Atlantic Forest stream in Brazil. The males of this species were territorial, varying in its local fidelity, while the females appear sporadically. Males were perched in the majority of the time, but were also observed in cleaning movements, longitudinal abdominal flexion, wing flexion and sperm transfer during perch. The males presented a perched thermoregulatory behavior related to an exothermic regulation. Foraging and agonistic interactions were rare, but dominate the other behavioral activities. Abdominal movements associated to long lasting copula pointed to the existence of sperm competition in this species. Males performed contact post-copulatory guarding of the females. These observations pointed to a non-resource mating system for this species.Ecologia comportamental de Heteragrion consors Hagen (Odonata: Megapodagrionidae: uma libélula de áreas sombreadas da Floresta Atlântica. A intensidade de seleção inter e intra-sexual deve afetar características comportamentais dos machos como fidelidade a territórios e agressividade possibilitando a existência de diferentes estratégias. No entanto, seu

  7. Effect of resin shades on opacity of ceramic veneers and polymerization efficiency through ceramics.

    Science.gov (United States)

    Öztürk, Elif; Chiang, Yu-Chih; Coşgun, Erdal; Bolay, Şükran; Hickel, Reinhard; Ilie, Nicoleta

    2013-11-01

    The aim of this study was to assess the effect of different resin cement shades on the opacity and color difference of ceramics and to determine the polymerization efficiency of the resin cement at different shades after curing through ceramics. Two different ceramics (IPS e.max Press and IPS Empress(®)CAD, Ivoclar Vivadent) were used for this study. A light-cured veneer luting resin (Variolink Veneer, Ivoclar Vivadent) in four different shades of HV+1, HV+3, LV-1, and LV-3 was used for the colorimetric measurements. The color and spectral reflectance of the ceramics were measured according to the CIELab color scale relative to the standard illuminant D65 on a reflection spectrophotometer (ColorEye7000A, USA). Color differences (ΔE values) and the contrast ratios (CR) of the different groups of samples were calculated. In order to analyse the polymerization efficiency of the resin cements, the micromechanical properties of the resins were measured with an automatic microhardness indenter (Fisherscope H100C, Germany). The results were analysed using one-way ANOVA and Tukey's HSD post hoc tests (SPSS 18.0). The one-way ANOVA test showed that the values of ΔE and CR of the different specimen groups were significantly different (presin cement) exhibited the highest and group 10 (14.8 ± 0.5) (e.max:HV+3) exhibited the lowest ΔE value. Significant differences in the micromechanical properties were identified among the tested resin cements in different shades (pResin cement shade is an important factor for the opacity of a restoration. Furthermore, the resin shade affects the micromechanical properties of the underlying resin cement. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Impact of shade on outdoor thermal comfort—a seasonal field study in Tempe, Arizona

    Science.gov (United States)

    Middel, Ariane; Selover, Nancy; Hagen, Björn; Chhetri, Nalini

    2016-12-01

    Shade plays an important role in designing pedestrian-friendly outdoor spaces in hot desert cities. This study investigates the impact of photovoltaic canopy shade and tree shade on thermal comfort through meteorological observations and field surveys at a pedestrian mall on Arizona State University's Tempe campus. During the course of 1 year, on selected clear calm days representative of each season, we conducted hourly meteorological transects from 7:00 a.m. to 6:00 p.m. and surveyed 1284 people about their thermal perception, comfort, and preferences. Shade lowered thermal sensation votes by approximately 1 point on a semantic differential 9-point scale, increasing thermal comfort in all seasons except winter. Shade type (tree or solar canopy) did not significantly impact perceived comfort, suggesting that artificial and natural shades are equally efficient in hot dry climates. Globe temperature explained 51 % of the variance in thermal sensation votes and was the only statistically significant meteorological predictor. Important non-meteorological factors included adaptation, thermal comfort vote, thermal preference, gender, season, and time of day. A regression of subjective thermal sensation on physiological equivalent temperature yielded a neutral temperature of 28.6 °C. The acceptable comfort range was 19.1 °C-38.1 °C with a preferred temperature of 20.8 °C. Respondents exposed to above neutral temperature felt more comfortable if they had been in air-conditioning 5 min prior to the survey, indicating a lagged response to outdoor conditions. Our study highlights the importance of active solar access management in hot urban areas to reduce thermal stress.

  9. Impact of shade on outdoor thermal comfort-a seasonal field study in Tempe, Arizona.

    Science.gov (United States)

    Middel, Ariane; Selover, Nancy; Hagen, Björn; Chhetri, Nalini

    2016-12-01

    Shade plays an important role in designing pedestrian-friendly outdoor spaces in hot desert cities. This study investigates the impact of photovoltaic canopy shade and tree shade on thermal comfort through meteorological observations and field surveys at a pedestrian mall on Arizona State University's Tempe campus. During the course of 1 year, on selected clear calm days representative of each season, we conducted hourly meteorological transects from 7:00 a.m. to 6:00 p.m. and surveyed 1284 people about their thermal perception, comfort, and preferences. Shade lowered thermal sensation votes by approximately 1 point on a semantic differential 9-point scale, increasing thermal comfort in all seasons except winter. Shade type (tree or solar canopy) did not significantly impact perceived comfort, suggesting that artificial and natural shades are equally efficient in hot dry climates. Globe temperature explained 51 % of the variance in thermal sensation votes and was the only statistically significant meteorological predictor. Important non-meteorological factors included adaptation, thermal comfort vote, thermal preference, gender, season, and time of day. A regression of subjective thermal sensation on physiological equivalent temperature yielded a neutral temperature of 28.6 °C. The acceptable comfort range was 19.1 °C-38.1 °C with a preferred temperature of 20.8 °C. Respondents exposed to above neutral temperature felt more comfortable if they had been in air-conditioning 5 min prior to the survey, indicating a lagged response to outdoor conditions. Our study highlights the importance of active solar access management in hot urban areas to reduce thermal stress.

  10. Individual Plasticity of the Shade Response of the Invasive Solidago canadensis in China.

    Directory of Open Access Journals (Sweden)

    Leshan Du

    Full Text Available To evaluate the population variation, individual plasticity, and local adaptability of Solidago canadensis in response to shade treatment, we conducted a common pots experiment with a total of 150 ramets (5 genets, 15 populations, and 2 treatments subjected to both control (natural light and shady treatment (10% of natural light. Shade treatment significantly reduced growth and content of defense metabolites in S. canadensis. Compared to control, shading led to increased height, decreased basal diameter, increased leaf width, increased leaf length, increased chlorophyll content, stronger photosynthetic rate (Pn, stronger stomatal conductance (gs, and lower root to shoot ratio. Three-way analysis of variance revealed geographical origin to significantly affect the basal diameter of S. canadensis, while genotype significantly affected plant height, intercelluar CO2 concentration (Ci, transpiration rate (Tr, and proline content. Significant interactive effects between shade and geographic origin were prevalent for most traits. The phenotypic differentiation coefficient of the plasticity of all traits was below 0.4, indicating that most of all variations can be found among individuals within populations. Phenotypic selection analysis revealed that fitness was significantly positively related to plant height, basal diameter, Ci, total flavonoid content, as well as the plasticity of plant height, leaf length, leaf width, gs, Ci, total flavonoid content, and malondialdehyde content under the control condition. However, subjected to shade, fitness was only significantly positively related to plant height, basal diameter, and the plasticity of basal diameter. Rather than local adaption, these results suggest that individual plasticity played a more prominent role in the shade response of the invasive S. canadensis.

  11. Microclimate, development and productivity of robusta coffee shaded by rubber trees and at full sun

    Directory of Open Access Journals (Sweden)

    André Vasconcellos Araújo

    2016-12-01

    Full Text Available ABSTRACT There are few studies about the shading of Robusta coffee with rubber trees. The aim of this study was evaluate the microclimate, development and yield of Coffea canephora grown at full sun and shaded by rubber trees. The experiment consisted of a Robusta coffee crop (Coffea canephora grown at under full sun and another coffee crop intercropped with rubber trees (Hevea brasiliensis. The rubber trees and coffee crop were planted in the East/West direction, in Jaguaré, Espírito Santo, Brazil. Was evaluated the luminosity, temperature and relative humidity, leaf nutrient concentrations; internodes of the plagiotropic and orthotropic branches, leaf area; relative chlorophyll index, and tree yield of the coffee crops. The shading directly influenced the microclimate by reducing the air temperature in the summer and winter, as well as by increasing relative humidity. Luminosity in the summer had an average decrease of 905 lumens ft-2 throughout the day, which was equivalent to 72.49%, and luminosity in the winter had an average decrease of 1665 lumens ft-2, which was equivalent to 88.04%. The shading provided greater etiolation of the plagiotropic and orthotropic branches as well as greater leaf expansion as compared to the full sun. The leaf concentration of Fe and Mn were higher in the shaded coffee. Estimated chlorophyll b and total chlorophyll were greater in the coffee crop grown at under full sun. The dense shading produced by rubber trees provided losses in the coffee crop yield, however, there is the formation of the rubber tree.

  12. Performance of Nellore males under different artificial shading levels in the feedlot

    Directory of Open Access Journals (Sweden)

    Diogo Alves da Costa Ferro

    2016-09-01

    Full Text Available The objective of this study was to evaluate the influence of artificial shading on weight gain and meat quality of male Nellore cattle in an intensive production system. The experiment was conducted in the experimental feedlot of the Course of Animal Science at Universidade Estadual de Goiás, from July to October 2014. Forty-eight male Nellore cattle with an average initial weight of 310 kg were kept in double 24-m2 stalls, in a total of 24 stalls. Of these, six were in the open air; six were covered with black shade netting of 30% light interception; six with black shade netting 50%; and six with black shade netting 80%, providing 6 m2 of shade per stall. The ration supplied to the animals and the orts left in the trough were weighed daily to determine intake, and the temperature-humidity index (THI was measured twice weekly. Animals were weighed for the first time at the start of the experiment, and then another three times until the end, which was followed by the slaughter and assessments of performance and meat quality. A difference (p 0.05 was observed for feed intake, initial weight, final weight, total weight gain, average daily weight gain, carcass yield, marbling, texture, fatness, backfat thickness, loin-eye area, color, thigh length and circumference, leg length and circumference, or carcass length between the animals on the different treatments. The use of artificial shading does not have a significant effect on performance or meat quality of feedlot Nellore cattle when the ambient temperature is within the thermal comfort zone.

  13. Effect of shading on yield, sugar content, phenolic acids and antioxidant property of coffee beans (Coffea Arabica L. cv. Catimor) harvested from north-eastern Thailand.

    Science.gov (United States)

    Somporn, Chanyarin; Kamtuo, Amnouy; Theerakulpisut, Piyada; Siriamornpun, Sirithon

    2012-07-01

    Environmental conditions, including shading, generally influence the physical and chemical qualities of coffee beans. The present study assessed the changes in some phenolic compounds, antioxidant activity and agronomic characters of coffee beans (Coffea arabica L. cv. Catimor) as affected by different shading conditions including full sun, three artificial shading conditions using a saran covering (50% shade, 60% shade, and 70% shade) and lychee shade. Bean weight and bean size increased significantly (P antioxidant activity compared to all other beans. Chlorogenic acid was the most predominant phenolic acid in all samples studied, being the highest in the beans grown under lychee shade, followed by 60% shade, 70% shade, 50% shade and full sun, respectively. In contrast, bean grown under full sun had the highest amount of vanillic acid and caffeic acid. Antioxidant activity was highly positively associated with chlorogenic acid content. The content of total sugar (fructose, glucose and sucrose) was found highest in coffee beans grown in 60% shade, with fructose the predominant sugar. Under climatic conditions similar to this experiment, it is advisable that growers provide shade to the coffee crop to reduce heat from direct sunlight and promote yield as well as obtain good quality coffee beans. Copyright © 2012 Society of Chemical Industry.

  14. Lighting and shading of PV systems in buildings: Visualisation, calculation of shading losses, optimisation; Licht und Schatten auf ``PV in Gebaeuden``: Visualisierung, Ertragsprognose, Optimierung

    Energy Technology Data Exchange (ETDEWEB)

    Reise, C. [Fraunhofer-Inst. fuer Solare Energiesysteme, Freiburg (Germany). Abt. fuer Photovoltaische Systeme und Messtechnik

    1998-02-01

    Integrating photovoltaic generators in buildings often requires a specific assessment of the local solar resource. In built-up areas, partial shading of the generator area sometimes cannot be avoided. A combination of the simulation tools RADIANCE and INSEL provides both a perfect visualization and an accurate estimation of shading losses, on the basis of the same numerical model of the building. Thus, simulation techniques help to meet both the aesthetical and the technical requirements of a building construction. (orig.) [Deutsch] Die Integration von photovoltaischen Generatoren in Gebaeude erfordert oft eine besondere Bewertung der lokalen Einstrahlungsverhaeltnisse. In einer dicht bebauten Umgebung kann eine zeitweise Teilverschattung der Generatorflaechen oft nicht vermieden werden. Eine Kombination der Simulationsprogramme RADIANCE und INSEL ermoeglicht die architektonisch vollwertige Visualisierung und Durchfuehrung einer praezisen (Minder-)Ertragsprognose fuer gebaeudeintegrierte Photovoltaik auf der Basis desselben numerischen Gebaeudemodells. Die detaillierte Simulation traegt dazu bei, aesthetische und technische Anforderungen an die Gebaeudekonstruktion in Einklang zu bringen. (orig.)

  15. Calculating the Effect of External Shading on the Solar Heat Gain Coefficient of Windows

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Christian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shukla, Yash [CEPT Univ., Ahmedabad (India); Rawal, Rajan [CEPT Univ., Ahmedabad (India)

    2017-08-09

    Current prescriptive building codes have limited ways to account for the effect of solar shading, such as overhangs and awnings, on window solar heat gains. We propose two new indicators, the adjusted Solar Heat Gain Coefficient (aSHGC) which accounts for external shading while calculating the SHGC of a window, and a weighted SHGC (SHGCw) which provides a seasonal SHGC weighted by solar intensity. We demonstrate a method to calculate these indices using existing tools combined with additional calculations. The method is demonstrated by calculating the effect of an awning on a clear double glazing in New Delhi.

  16. Effect of brand and shade of resin cements on the final color of lithium disilicate ceramic.

    Science.gov (United States)

    Dede, Doğu Ömür; Ceylan, Gözlem; Yilmaz, Burak

    2017-04-01

    Resin cements are available in various shades from different manufacturers. However, there is no standard for the optical properties of these cements, which may result in differences in the color of translucent ceramic restorations. The purpose of this in vitro study was to evaluate the effects of different shades and brands of resin cements on the color of a lithium disilicate ceramic. Ten ceramic disks (11×1.5 mm, shade A2) were fabricated from lithium disilicate high-translucency blocks. Eighty cement disks (11×0.2 mm) were fabricated from 4 brands (Maxcem; Variolink; Clearfil; and RelyX) of resin cements in translucent and universal (shade A2) shades. Color measurements of ceramic specimens were made without (control) and with each brand/shade of resin cement material (test) with a spectrophotometer, and International Commission on Illumination Lab (CIELab) color coordinates were recorded. Color differences (ΔE00) between the control and test groups were calculated. ΔE00 results were analyzed by 2-way ANOVA and subsequent pairwise testing. Comparisons were performed using the Student t test, and then all P values were corrected with the step-down Bonferroni procedure (α=.05). The effect on the ΔE00 values (Ptranslucent cement group had significantly higher ΔE00 results than other brands (Ptranslucent and RelyX_universal were significantly different from each other for comparisons within brands (Pceramic was not visually perceptible (ΔE00≤1.30). Clinically unacceptable results (ΔE00>2.25) were observed only for Variolink_translucent cement (2.36). Same-shade resin cements from different manufacturers had different effects on the color of lithium disilicate ceramic. The effects of different shades of resin cements from the same manufacturer on the color of lithium disilicate ceramic were statistically different for only RelyX, which may also be considered clinically different based on clinical acceptability thresholds for color difference values (

  17. Accurate Maximum Power Tracking in Photovoltaic Systems Affected by Partial Shading

    Directory of Open Access Journals (Sweden)

    Pierluigi Guerriero

    2015-01-01

    Full Text Available A maximum power tracking algorithm exploiting operating point information gained on individual solar panels is presented. The proposed algorithm recognizes the presence of multiple local maxima in the power voltage curve of a shaded solar field and evaluates the coordinated of the absolute maximum. The effectiveness of the proposed approach is evidenced by means of circuit level simulation and experimental results. Experiments evidenced that, in comparison with a standard perturb and observe algorithm, we achieve faster convergence in normal operating conditions (when the solar field is uniformly illuminated and we accurately locate the absolute maximum power point in partial shading conditions, thus avoiding the convergence on local maxima.

  18. Vitapan 3D-master shade guide showed no fluorescence emission

    Directory of Open Access Journals (Sweden)

    Yong-Keun Lee

    2012-01-01

    Results and Conclusion: ΔE FNx01ab-FL values were in the range of 0.2 to 2.7 (mean: 1.2±0.6 for the original and 0.5 to 1.6 (mean: 0.9±0.1 for the ground-to-flat tabs, which was significantly different based on paired t-test (p<0.05; however, fluorescence peak was not detected in all the shade tabs. Therefore, fluorescence property of Vitapan 3D-Master shade guide should be modified to have similarfluorescence property of natural teeth and corresponding restorative materials.

  19. Tissue-level leaf toughness, but not lamina thickness, predicts sapling leaf lifespan and shade tolerance of tropical tree species

    NARCIS (Netherlands)

    Kitajima, K.; Poorter, L.

    2010-01-01

    Leaf toughness is thought to enhance physical defense and leaf lifespan. Here, we evaluated the relative importance of tissue-level leaf traits vs lamina thickness, as well as their ontogenetic changes, for structure-level leaf toughness and regeneration ecology of 19 tropical tree species. We

  20. Toleration out of respect?

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    be based on a modus vivendi designed to secure peaceful co-existence, but should be based on moral reasons. Forst therefore advances what he calls the ‘respect conception’ of toleration as an in itself morally desirable type of relationship, which is furthermore the only conception of toleration......Under conditions of pluralism different cultures, interests or values can come into conflict, which raises the problem of how to secure peaceful co-existence. The idea of toleration historically emerged as an answer to this problem. Recently Rainer Forst has argued that toleration should not just...... that avoids various so-called ‘paradoxes of toleration’. The paper first examines whether Forst’s respect conception can be applied descriptively to distinguish between actual patterns of behaviour and classify different acts of toleration. Then the focus is shifted to toleration out of respect as a normative...

  1. Detection of renal artery stenoses using MRI with surface shaded display. Interest in azotemic patients; Dectection des stenoses arterielles renales par IRM avec reconstruction surfacique. Interet chez l`insuffisant renal chronique

    Energy Technology Data Exchange (ETDEWEB)

    Thony, F.; Paul, J.F.; Ferretti, G.; Janbon, B.; Le Bas, J.F.; Fauconnier, G.; Cordonnier, D.; Coulomb, M. [Centre Hospitalier Universitaire, 38 - Grenoble (France)

    1997-09-01

    Forty-three patients with renal artery stenoses were examined with time of flight MR angiography using maximum intensity projection and surface shaded rendering, and with digital substraction angiography. Sensitivity and specificity were 0.83 and 0.78 for main and secondary arteries, 0.87 and 0.84 for main arteries. In azotemic patients, the positive predictive value was estimated at 40 %-70 % and the negative predictive value at 95 %- 98 %, while the prevalence of renal artery stenoses varied from 10 % to 30 %. These results validate MRI for the detection of renal artery stenoses in this population. Surface shaded display was more accurate than maximum intensity projection to reconstruct time of flight sequences and to grade renal artery stenoses. (authors). 21 refs.

  2. Tolerance to solar ultraviolet-B radiation in the citrus red mite, an upper surface user of host plant leaves.

    Science.gov (United States)

    Fukaya, Midori; Uesugi, Ryuji; Ohashi, Hirokazu; Sakai, Yuta; Sudo, Masaaki; Kasai, Atsushi; Kishimoto, Hidenari; Osakabe, Masahiro

    2013-01-01

    Plant-dwelling mites are potentially exposed to solar ultraviolet-B (UVB) radiation that causes deleterious and often lethal effects, leading most mites to inhabit the lower (underside) leaf surfaces. However, in species of spider mite belonging to the Genus Panonychus, a substantial portion of individuals occur on upper leaf surfaces. We investigated whether the upper leaf surfaces of citrus trees are favorable for P. citri, and to what extent they are tolerant to UVB radiation. If eggs are not adequately protected from UVB damage, females may avoid ovipositing on the upper surfaces of sunny leaves. To test this, we conducted laboratory experiments using a UVB lamp, and semioutdoor manipulative experiments. As a result, P. citri eggs are tolerant to UVB. Field studies revealed that the ratio of eggs and adult females on upper leaf surfaces were larger for shaded than for sunny leaves. However, 64-89% of eggs hatched successfully even on sunny upper leaf surfaces. Nutritional evaluation revealed that whether on sunny or shaded leaves, in fecundity and juvenile development P. citri reaped the fitness benefits of upper leaf surfaces. Consequently, P. citri is tolerant to UVB damage, and inhabiting the upper surfaces of shaded leaves is advantageous to this mite. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  3. Recognition and Toleration

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2010-01-01

    Recognition and toleration are ways of relating to the diversity characteristic of multicultural societies. The article concerns the possible meanings of toleration and recognition, and the conflict that is often claimed to exist between these two approaches to diversity. Different forms or inter......Recognition and toleration are ways of relating to the diversity characteristic of multicultural societies. The article concerns the possible meanings of toleration and recognition, and the conflict that is often claimed to exist between these two approaches to diversity. Different forms...

  4. Sulfur tolerant anode materials

    Energy Technology Data Exchange (ETDEWEB)

    1987-02-01

    The goal of this program is the development of a molten carbonate fuel cell (MCFC) anode which is more tolerant of sulfur contaminants in the fuel than the current state-of-the-art nickel-based anode structures. This program addresses two different but related aspects of the sulfur contamination problem. The primary aspect is concerned with the development of a sulfur tolerant electrocatalyst for the fuel oxidation reaction. A secondary issue is the development of a sulfur tolerant water-gas-shift reaction catalyst and an investigation of potential steam reforming catalysts which also have some sulfur tolerant capabilities. These two aspects are being addressed as two separate tasks.

  5. Toleration, Groups, and Multiculturalism

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    to the political and social relationship between the subject and the objects of toleration. Finally, toleration is often argued to be a normative requirement on the basis of the way it affects the object or receiver of toleration, e.g. on the basis of the good of or right to freedom from non-interference which....... The chapter relates the different possible meanings of groups toleration to widespread criticisms of multiculturalism for being excessively 'groupist' (e.g. to essentialise or reify groups), to promote group rights over individual rights, or to deny or ignore the internal heterogeneity of groups...

  6. Shading aboveground L-joint and lap-joint tests : comparison of white pine and sugar maple test assemblies

    Science.gov (United States)

    Carol A. Clausen; Daniel L. Lindner

    2011-01-01

    Five-year performance ratings are presented for two types of untreated, uncoated wood joints (L and lap) in aboveground tests under shaded conditions. The effect of shading on moisture entrapment in pine and maple L and lap joints was evaluated in a moderate decay zone (Madison, Wisconsin). Variations were observed between wood species, visual ratings, joint type,...

  7. 100-Meter Resolution Grayscale Shaded Relief of Puerto Rico and the U.S. Virgin Islands - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Grayscale Shaded Relief of Puerto Rico and the U.S. Virgin Islands map layer is a 100-meter resolution grayscale shaded relief image of Puerto Rico and the U.S....

  8. Impacts of Shading on Sponge-Cyanobacteria Symbioses: A Comparison between Host-Specific and Generalist Associations.

    Science.gov (United States)

    Thacker, Robert W

    2005-04-01

    The marine sponge Lamellodysidea chlorea contains large populations of the host-specific, filamentous cyanobacterium Oscillatoria spongeliae. Other marine sponges, including Xestospongia exigua, contain the generalist, unicellular cyanobacterium Synechococcus spongiarum. The impact of cyanobacterial photosynthesis on host sponges was manipulated by shading these sponge-cyanobacteria associations. If cyanobacteria benefit their hosts, shading should reduce this benefit. Chlorophyll a concentrations were measured as an index of cyanobacterial abundance. After two weeks, shaded L. chlorea lost more mass than controls, while shaded and control X. exigua did not lose a significant amount of mass. Chlorophyll a concentrations in shaded X. exigua were lower than in controls, but were not significantly different between shaded and control L. chlorea. In addition, L. chlorea shaded in situ lost over 40% of their initial area, but did not differ in chlorophyll a concentrations from controls. These results suggest that Oscillatoria symbionts benefit their host sponges in a mutualistic association. Synechococcus symbionts may be commensals that exploit the resources provided by their sponge hosts without significantly affecting sponge mass. When shaded, Synechococcus symbionts may be consumed by their hosts or may be able to disperse from this unfavorable environment. These data support the hypothesis that more specialized symbionts provide a greater benefit to their hosts, but hypotheses concerning the dispersal abilities of these symbionts remain to be explored. Sponge-cyanobacteria symbioses provide model systems for investigating the costs and benefits of symbiosis and the roles of dispersal, environmental conditions, and phylogenetic history in determining the specificity of endosymbionts for their hosts.

  9. Einstein Equations from Varying Complexity

    Science.gov (United States)

    Czech, Bartłomiej

    2018-01-01

    A recent proposal equates the circuit complexity of a quantum gravity state with the gravitational action of a certain patch of spacetime. Since Einstein's equations follow from varying the action, it should be possible to derive them by varying complexity. I present such a derivation for vacuum solutions of pure Einstein gravity in three-dimensional asymptotically anti-de Sitter space. The argument relies on known facts about holography and on properties of tensor network renormalization, an algorithm for coarse-graining (and optimizing) tensor networks.

  10. Fiction or not? Fifty Shades is associated with health risks in adolescent and young adult females.

    Science.gov (United States)

    Bonomi, Amy E; Nemeth, Julianna M; Altenburger, Lauren E; Anderson, Melissa L; Snyder, Anastasia; Dotto, Irma

    2014-09-01

    No prior study has empirically characterized the association between health risks and reading popular fiction depicting violence against women. Fifty Shades--a blockbuster fiction series--depicts pervasive violence against women, perpetuating a broader social narrative that normalizes these types of risks and behaviors in women's lives. The present study characterized the association between health risks in women who read and did not read Fifty Shades; while our cross-sectional study design precluded causal determinations, an empirical representation of the health risks in women consuming the problematic messages in Fifty Shades is made. Females ages 18 to 24 (n=715), who were enrolled in a large Midwestern university, completed a cross-sectional online survey about their health behaviors and Fifty Shades' readership. The analysis included 655 females (219 who read at least the first Fifty Shades novel and 436 who did not read any part of Fifty Shades). Age- and race-adjusted multivariable models characterized Fifty Shades' readers and nonreaders on intimate partner violence victimization (experiencing physical, sexual and psychological abuse, including cyber-abuse, at some point during their lifetime); binge drinking (consuming five or more alcoholic beverages on six or more days in the last month); sexual practices (having five or more intercourse partners and/or one or more anal sex partner during their lifetime); and using diet aids or fasting for 24 or more hours at some point during their lifetime. One-third of subjects read Fifty Shades (18.6%, or 122/655, read all three novels, and 14.8%, or 97/655, read at least the first novel but not all three). In age- and race-adjusted models, compared with nonreaders, females who read at least the first novel (but not all three) were more likely than nonreaders to have had, during their lifetime, a partner who shouted, yelled, or swore at them (relative risk [RR]=1.25) and who delivered unwanted calls/text messages

  11. Ecophysiological consequences of contrasting microenvironments on the desiccation tolerant moss Tortula ruralis.

    Science.gov (United States)

    Hamerlynck, Erik P; Csintalan, Zsolt; Nagy, Zoltan; Tuba, Zoltan; Goodin, Doug; Henebry, Geoffrey M

    2002-05-01

    Tortula ruralis is a homoiochlorophyllous-desiccation-tolerant (HDT) moss that retains all pigments when dehydrated and rapidly recovers physiological function upon rehydration. This moss forms extensive cover in exposed and shaded areas in the sandy semi-arid grasslands of Central Europe. We hypothesized that contrasting drying regimes between these microhabitats would affect plant N status, constraints to gas exchange and growth, as well as result in altered pigment concentrations and ratios, and photochemical light-response dynamics. Furthermore, we believed T. ruralis's HDT habit would limit its ability to acclimate to altered light environment. We found that sun plant T. ruralis had lower plant mass, as well as lower tissue N, C, total photosynthetic pigment concentrations and carbon isotope discrimination (Δ) values compared to shade plant counterparts. Carotenoid/chlorophyll ratios in sun plants were typical of high light-adapted tissue, but chlorophyll a/chlorophyll b ratios were lower, more characteristic of low light-adapted tissue. This unique combination of pigment responses was accompanied by sustained lower levels of optimal quantum efficiency of PSII (F v /F m ) in sun plant T. ruralis, even during favorable diurnal conditions, and reduced engagement of energy-dependent thermal dissipation (NPQ). Reciprocal transplants of sun and shade plants showed that T. ruralis is capable of short-term adjustment to altered light level, as evidenced by increases in F v /F m , NPQ, and light-adapted PSII yield (φ PSII ) in transplanted sun plants, and concurrent decreases in sun-transplanted shade plants. However, the performance of transplanted sun plants remained consistently below that of undisturbed shade plants. These findings show that microenvironmental variation results in different patterns of resource acquisition in this HDT moss, and that growth in the open imparts greater desiccation tolerance, and the development of a greater standing engagement of

  12. INFLUENCE OF SUPERPLASTICIZER AND VARYING ...

    African Journals Online (AJOL)

    This paper presents the results of the study on the influence of superplasticizer and varying aggregate size on the drying shrinkage and compressive strength of laterised concrete. Four different samples of laterised concrete were made from prescribed mix ratio of 1:1:2 which include; two control specimens made with ...

  13. Optimistlik Karlovy Vary / Jaan Ruus

    Index Scriptorium Estoniae

    Ruus, Jaan, 1938-2017

    2007-01-01

    42. Karlovy Vary rahvusvahelise filmifestivali auhinnatud filmidest (žürii esimees Peter Bart). Kristallgloobuse sai Islandi-Saksamaa "Katseklaasilinn" (režii Baltasar Kormakur), parimaks režissööriks tunnistati norralane Bard Breien ("Negatiivse mõtlemise kunst"). Austraallase Michael James Rowlandi "Hea õnne teekond" sai žürii eripreemia

  14. Esmaklassiline Karlovy Vary / Jaanus Noormets

    Index Scriptorium Estoniae

    Noormets, Jaanus

    2007-01-01

    Ilmar Raagi mängufilm "Klass" võitis 42. Karlovy Vary rahvusvahelise filmifestivalil kaks auhinda - ametliku kõrvalvõistlusprogrammi "East of the West" eripreemia "Special mention" ja Euroopa väärtfilmikinode keti Europa Cinemas preemia. Ka Asko Kase lühifilmi "Zen läbi prügi linastumisest ning teistest auhinnasaajatest ning osalejatest

  15. Time-varying Crash Risk

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Feunoua, Bruno; Jeon, Yoontae

    We estimate a continuous-time model with stochastic volatility and dynamic crash probability for the S&P 500 index and find that market illiquidity dominates other factors in explaining the stock market crash risk. While the crash probability is time-varying, its dynamic depends only weakly...

  16. Eestlased Karlovy Varys / J. R.

    Index Scriptorium Estoniae

    J. R.

    2007-01-01

    Ilmar Raagi mängufilm "Klass" osaleb 42. Karlovy Vary rahvusvahelise filmifestivali võistlusprogrammis "East of the West" ja Asko Kase lühimängufilm "Zen läbi prügi" on valitud festivali kõrvalprogrammi "Forum of Independents"

  17. Freeze-Tolerant Condensers

    Science.gov (United States)

    Crowley, Christopher J.; Elkouhk, Nabil

    2004-01-01

    Two condensers designed for use in dissipating heat carried by working fluids feature two-phase, self-adjusting configurations such that their working lengths automatically vary to suit their input power levels and/or heat-sink temperatures. A key advantage of these condensers is that they can function even if the temperatures of their heat sinks fall below the freezing temperatures of their working fluids and the fluids freeze. The condensers can even be restarted from the frozen condition. The top part of the figure depicts the layout of the first condenser. A two-phase (liquid and vapor) condenser/vapor tube is thermally connected to a heat sink typically, a radiatively or convectively cooled metal panel. A single-phase (liquid) condensate-return tube (return artery) is also thermally connected to the heat sink. At intervals along their lengths, the condenser/vapor tube and the return artery are interconnected through porous plugs. This condenser configuration affords tolerance of freezing, variable effective thermal conductance (such that the return temperature remains nearly constant, independently of the ultimate sink temperature), and overall pressure drop smaller than it would be without the porous interconnections. An additional benefit of this configuration is that the condenser can be made to recover from the completely frozen condition either without using heaters, or else with the help of heaters much smaller than would otherwise be needed. The second condenser affords the same advantages and is based on a similar principle, but it has a different configuration that affords improved flow of working fluid, simplified construction, reduced weight, and faster recovery from a frozen condition.

  18. Objective measurement of shade color in age estimation

    OpenAIRE

    Sharad Vaidya; Nitin Ahuja; Puneet Bajaj; Charu Kapoor; Robin Sabarwal; Karan Rajpal

    2015-01-01

    Introduction : Age estimation is an important subspecialty of forensic medicine. Dental hard tissues are highly resistant to degradation and putrefaction. Enamel is translucent and varies in color from light yellow to grey white . The color of the teeth has been reported to be affected by chronological age. Enamel color may also depend on environmental factors viz. diet, occupational habits, vitamin deficiencies, fluoride level in drinking water etc., It has been found that color changes in d...

  19. Assessment of the influence of gender and skin color on the preference of tooth shade in Saudi population.

    Science.gov (United States)

    Labban, Nawaf; Al-Otaibi, Hanan; Alayed, Abdulaziz; Alshankiti, Khaled; Al-Enizy, Mohammad A

    2017-07-01

    The aim of the study was to evaluate the influence of gender and skin color on the preference of different teeth shades in general population. Two standardized frontal smile photographs of male and female subjects were manipulated using photoshop to represent 4 skin colors [(type II, III, IV, and V) (Fitzpatrick scale)]. The teeth shades under each skin color were digitally manipulated to represent one of 6 teeth shades (BL1, BL2, BL3, BL4, B1 and A1). A questionnaire assessed demographic characteristics (age, nationality, gender, education level, occupation, and income) along with the satisfaction of their smiles. Male and female set of pictures with combination of skin colors and teeth shades were presented and participants were asked to select the most esthetically pleasing teeth shade with regard to gender and skin color. Cross-tabulations and chi-squared tests were used to perform the statistical analyses (α = 0.05). Three hundred and thirty-six (60.4% male; 39.6% female) individuals participated in the study. The difference in the preferred teeth shades was significant among the male and female photographs across all skin colors (p color. In addition, lighter teeth shades were preferred among subjects with a lighter skin color and vice versa (p Gender and skin color influences the perception of teeth shades among general population. Therefore, lighter tooth shades (BL1, BL2) for lighter skin color and comparatively darker tooth shades (BL4, B1, A1) for darker skin individuals should be prescribed as these are perceived as natural among Saudi population.

  20. The effect of ceramic thickness and resin cement shades on the color matching of ceramic veneers in discolored teeth.

    Science.gov (United States)

    Xing, Wenzhong; Chen, Xiaodong; Ren, Dafei; Zhan, Kangru; Wang, Yining

    2017-10-01

    The objective of this study was to analyze the effects of ceramic material thickness and resin cement shade on the color matching of ceramic veneers at the gray tooth structures. Seventy-two artificial maxillary right central incisor teeth (C2 shade) were prepared according to veneer tooth preparation in practice. Ceramic materials (LT, A2 shade, IPS e.max Press) were selected to fabricate the 0.50- and 0.75-mm thick veneers at the body region. The ceramic veneer specimens were bonded to the artificial teeth by the 6 shades of resin cements (Variolink Veneer: shades of HV+3, LV-2, LV-3; and RelyX TM Veneer: shades of WO, TR, A3). A clinical spectrophotometer (Crystaleye, Olympus) was used to measure the color parameters. The color differences (ΔE values) of ceramic veneers and A2 shade tab (Vitapan Classical, Vita) and C* ab values were calculated. The results of three-way ANOVA indicated that the ΔE values of ceramic veneer and A2 shade tab were significantly different in the thickness of ceramic materials, shades of resin cements, and measuring regions (p veneers that exhibited higher ΔE values compared with veneers that were 0.75-mm thick. Tukey's HSD test showed that the average ΔE values in body region were significantly smaller than that in cervical and incisal regions. The color matching of ceramic veneers was significantly influenced not only by the ceramic thickness and the resin cement shades but also the tooth regions.

  1. The effect of repeated firings on the color of an all-ceramic system with two different veneering porcelain shades.

    Science.gov (United States)

    Celik, Gozde; Uludag, Bulent; Usumez, Aslihan; Sahin, Volkan; Ozturk, Ozge; Goktug, Gurkan

    2008-03-01

    Color matching between a restoration and natural teeth is a common clinical problem. Despite careful shade selection, color of the restoration may be affected by fabrication procedures. The purpose of this study was to determine the color changes of an all-ceramic restoration with 2 different veneering porcelain shades after repeated firings. Twenty disc-shaped ceramic specimens, 4 mm in diameter with a 1-mm core thickness and 2 different veneering porcelain shades (A1, A3), were fabricated from a zirconia-based porcelain (DC-Zirkon) (n=10). Repeated firings (3, 5, 7, or 9 firings) were performed for the specimens, and color differences (DeltaE) were determined using a spectrophotometer. Repeated measures ANOVA was used to analyze the data (number of firings, veneering porcelain color). The Tukey HSD test and paired 2-tailed tests were performed for multiple comparisons (alpha=.05). The L*a*b* values of the ceramic system were affected by the number of firings (3, 5, 7, or 9) (Pveneering porcelain shade (Pveneering porcelain shade for L* (P=.003) and b* (P=.042) values, but not for the a* value (P=.82). An increase in the number of firings of the specimens with both A1 and A3 veneering porcelain shades produced an increase in the L* value, resulting in lighter specimens (Pveneering porcelain shades, the a* value decreased after repeated firings, which resulted in more green specimens (P=.002). The b* value did not change after repeated firings (P=.09) for the A1 veneering porcelain shade; however, it increased for the A3 veneering porcelain shade, which resulted in more yellow specimens (P=.001). The color of the all-ceramic specimens with different veneering porcelain shades is influenced by repeated firings. However, color changes that occurred are clinically acceptable.

  2. Effect of shading on tomato plants grow under greenhouse Efeito do sombreamento sobre o crescimento do tomateiro em cultivo protegido

    Directory of Open Access Journals (Sweden)

    Miguel Angelo Sandri

    2003-12-01

    Full Text Available The experiment was conducted at Universidade Federal de Santa Maria, Rio Grande do Sul State, Brazil, to determine the effect of shading on tomato plants grown in a greenhouse. Sowing was done on July 4th and planting on August 27th, 2000, in a plant density of 3.3 plants m-2, using an organic commercial rooting medium. Water and nutrients were supplied on a daily basis using a nutrient solution. Two polyethylene tunnels (2.20 m height, 5 m width, 15 m length were used. In the first plastic tunnel, used as control, the transmissivity of global radiation was 83% and plants were conducted as a commercial crop. In the second tunnel, plants were grown under a 52% shading screen. Plant growth and development were measured at 19; 26; 33; 40; 47; 54; 61; 75 and 89 days after beginning of anthesis. Daily average solar radiation in the first tunnel from planting time to the end of the experiment was 12.4 MJ m-2 day-1, whereas in the shaded tunnel it was 5.0 MJ m-2 day-1. Number of fruits per square meter did not differ significantly between the unshaded control and shaded tomato plants. At the last harvest, dry mass from unshaded and shaded plants differed significantly, with values of 974.9 g m-2 and 762.5 g m-2 for total dry mass, 550.1 g m-2 and 419.74 g m-2 for fruits, and 424.75 g m-2 and 342.74 g m-2 for vegetative organs, respectively. Total plant growth was reduced to 21.7% by shading, but plants continued to grow, in spite of the radiation level below the trophic limit of 8.4 MJ m-2 day-1. To establish the climatic suitability of horticultural crops in different regions, it should be advisable to take in account other variables than solar radiation.O experimento foi conduzido na Universidade Federal de Santa Maria, para determinar o efeito do sombreamento sobre o crescimento do tomateiro em cultivo protegido. A semeadura foi feita em 04/07/00 e o plantio em 27/08, na densidade de 3,3 plantas m-2, empregando substrato comercial orgânico. A

  3. Remember Tolerance Differently

    DEFF Research Database (Denmark)

    Tønder, Lars

    2012-01-01

    This essay questions the linear conception of history which often accompanies the way contemporary democratic theory tends to disavow tolerance's discontinuities and remainders. In the spirit of Foucault's genealogy of descent, the idea is to develop a new sense of tolerance's history, not by inv...

  4. Toleration out of respect?

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2013-01-01

    Under conditions of pluralism different cultures, interests or values can come into conflict, which raises the problem of how to secure peaceful co-existence. The idea of toleration historically emerged as an answer to this problem. Recently Rainer Forst has argued that toleration should not just...

  5. Tolerances in micro manufacturing

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Zhang, Yang; Islam, Aminul

    2017-01-01

    This paper describes a method for analysis of tolerances in micro manufacturing. It proposes a mapping oftolerances to dimensions and compares this with current available international standards. The analysisdocuments that tolerances are not scaled down as the absolute dimension. In practice...

  6. Tolerances in micro manufacturing

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Zhang, Yang; Islam, Aminul

    This paper describes a method for analysis of tolerances in micro manufacturing. It proposes a mapping oftolerances to dimensions and compares this with current available international standards. The analysisdocuments that tolerances are not scaled down as the absolute dimension. In practice...

  7. Fault Tolerant Feedback Control

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.

    2001-01-01

    An architecture for fault tolerant feedback controllers based on the Youla parameterization is suggested. It is shown that the Youla parameterization will give a residual vector directly in connection with the fault diagnosis part of the fault tolerant feedback controller. It turns out that there...

  8. Recognition and Toleration

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2010-01-01

    Recognition and toleration are ways of relating to the diversity characteristic of multicultural societies. The article concerns the possible meanings of toleration and recognition, and the conflict that is often claimed to exist between these two approaches to diversity. Different forms or inter...

  9. Tolerance – a Culturally Dependent Concept?

    Directory of Open Access Journals (Sweden)

    Trond Jørgensen

    2014-12-01

    human nature with an ‘inter-dependent construal of self’, counts as a context for tolerance. Also, it could be argued that Japanese religion is less doctrinal and absolute, and particularistic morality prevails. In the Japanese setting, the coexistence of competing truth systems seems to be more easily tolerated. This may broaden the room for tolerance. The cultural values defining ‘the good’ vary, implying that culture counts when the limits for tolerance are drawn. What is valued is culturally dependent, thus directing what is tolerated.        

  10. Shading and root-shoot relations in saplings of silver birch, pedunculate oak and beech

    NARCIS (Netherlands)

    Hees, van A.F.M.; Clerkx, A.P.P.M.

    2003-01-01

    Silver birch (Betula pendula Roth), pedunculate oak (Quercus robur L.) and beech (Fagus sylvatica L.) can regenerate successfully under a canopy of Scots pine (Pinus sylvestris L.). Shading reduces plant growth and modifies plant form, two related aspects. This study focuses on the effects of

  11. Shaded Coffee and Cocoa : Double Dividend for Biodiversity and Small-scale Farmers

    NARCIS (Netherlands)

    Jezeer, Rosalien E.; Verweij, Pita A.; Ferreira Dos Santos, Maria Joao; Boot, René G.A.

    2017-01-01

    This paper compares financial and biodiversity performance of small-scale shaded coffee and cocoa plantations versus intensified conventional ones. We conduct a meta-analysis including 23 studies on coffee and cocoa plantations over a 26 year period. Our results show that, contrary to common

  12. Effects of nutrients and shade on tree-grass interactions in an East African savanna.

    NARCIS (Netherlands)

    Ludwig, F.; Kroon, de H.; Prins, H.H.T.; Berendse, F.

    2001-01-01

    Savanna trees have a multitude of positive and negative effects on understorey grass production. but little is known about how these effects interact. We report on a fertilization and shading experiment carried out in a Tanzanian tropical city savanna around Acacia tortilis trees. In two years of

  13. Interactions between carbon sequestration and shade tree diversity in a smallholder coffee cooperative in El Salvador.

    Science.gov (United States)

    Richards, Meryl Breton; Méndez, V Ernesto

    2014-04-01

    Agroforestry systems have substantial potential to conserve native biodiversity and provide ecosystem services. In particular, agroforestry systems have the potential to conserve native tree diversity and sequester carbon for climate change mitigation. However, little research has been conducted on the temporal stability of species diversity and aboveground carbon stocks in these systems or the relation between species diversity and aboveground carbon sequestration. We measured changes in shade-tree diversity and shade-tree carbon stocks in 14 plots of a 35-ha coffee cooperative over 9 years and analyzed relations between species diversity and carbon sequestration. Carbon sequestration was positively correlated with initial species richness of shade trees. Species diversity of shade trees did not change significantly over the study period, but carbon stocks increased due to tree growth. Our results show a potential for carbon sequestration and long-term biodiversity conservation in smallholder coffee agroforestry systems and illustrate the opportunity for synergies between biodiversity conservation and climate change mitigation. © 2013 Society for Conservation Biology.

  14. Effects of shade and drought stress on soybean hormones and yield ...

    African Journals Online (AJOL)

    Multiple frequently interactive stress factors naturally influence plant due to global change. The leaf's hormone concentrations, main-stem and branch yield response to the combination of shade and drought were studied in a greenhouse experiment during 2009 and 2010 seasons. Pot experiments were conducted under ...

  15. Variation in performance of beech saplings of 7 European provenances under shade and full light conditions

    NARCIS (Netherlands)

    Kramer, K.; Hees, van A.F.M.; Jans, W.W.P.

    2001-01-01

    The use of beech seedlings from South-East European and North-West (NW) provenances for underplanting in coniferous forests in North-West Europe was investigated by means of experimental shading. The effects of this treatment on survival, morphology, phenology, physiology and growth were analysed by

  16. Initial characterization of shade avoidance response suggests functional diversity between Populus phytochrome B genes.

    Science.gov (United States)

    Karve, Abhijit A; Jawdy, Sara S; Gunter, Lee E; Allen, Sara M; Yang, Xiaohan; Tuskan, Gerald A; Wullschleger, Stan D; Weston, David J

    2012-11-01

    Shade avoidance signaling involves perception of incident red/far-red (R/FR) light by phytochromes (PHYs) and modulation of downstream transcriptional networks. Although these responses are well studied in Arabidopsis, little is known about the role of PHYs and the transcriptional responses to shade in the woody perennial Populus. Tissue expression and subcellular localization of Populus PHYs was studied by quantitative real-time PCR (qRT-PCR) and protoplast transient assay. Transgenic lines with altered PHYB1 and/or PHYB2 expression were used in phenotypic assays and transcript profiling with qRT-PCR. RNA-Seq was used to identify transcriptional responses to enriched FR light. All three PHYs were differentially expressed among tissue types and PHYBs were targeted to the nucleus under white light. Populus PHYB1 rescued Arabidopsis phyB mutant phenotypes. Phenotypes of Populus transgenic lines and the expression of candidate shade response genes suggested that PHYB1 and PHYB2 have distinct yet overlapping functions. RNA-Seq analysis indicated that genes associated with cell wall modification and brassinosteroid signaling were induced under enriched FR light in Populus. This study is an initial attempt at deciphering the role of Populus PHYs by evaluating transcriptional reprogramming to enriched FR and demonstrates functional diversity and overlap of the Populus PHYB1 and PHYB2 in regulating shade responses. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  17. Shading correction and calibration in bacterial fluorescence measurement by image processing system

    NARCIS (Netherlands)

    Wilkinson, M.H.F.

    An image processing system with applications in bacterial (immuno-)fluorescence measurement has been developed. To reach quantitative results, correction for non-uniformities in system sensitivity, both as a function of time (calibration for drifts) and as a function of image coordinates (shading

  18. Plant responses to simultaneous stress of waterlogging and shade: amplified or hierarchical effects?

    NARCIS (Netherlands)

    Lenssen, J.P.M.; Menting, F.B.J.; Van der Putten, W.H.

    2003-01-01

    Community ecologists often assume a hierarchy of environmental sieves to predict the impact of multiple stresses on species distribution. We tested whether this assumption corresponds to physiological responses using impact of water level and shade in wetland vegetation as a model. Seedlings of four

  19. A new shading concept based on natural tooth color applied to direct composite restorations

    OpenAIRE

    Dietschi, Didier; Ardu, Stefano; Krejci, Ivo

    2006-01-01

    Patient demands have prompted manufacturers to improve intrinsic optical properties of resin composites and clinicians to refine application procedures. The aim of this study is to present a shading concept based on colorimetric L*a*b* and contrast ratio data of human dentin and enamel.

  20. Shading concepts and layering techniques to master direct anterior composite restorations: an update.

    Science.gov (United States)

    Dietschi, D; Fahl, N

    2016-12-16

    Creating perfect direct composite restorations has been for long time a strict challenge due to many materials' limitations impacting either shade integration or surface quality, and possibly colour stability. Next to technological drawbacks, a certain complexity and lack of predictability in clinical application was inherent to the technique and made it elitist for a long time. Shading and layering concepts then progressively evolved from a simplistic, non histo-anatomical, bilaminar technique to a multi-layering approach (3 to 4 or more layers), following the Vita Classic(™) system. One of the most achieved concepts is polychromatic layering which makes use of a variable number of layers (basically VITA(™) or non-VITA(™) opacious dentin, chromatic enamel and translucent/opalescent enamel), driven by the natural tooth optical composition. In parallel with this evolution, a simplified, non-VITA shading system was developed with a reduced number of layers (basically dentin &enamel layer, plus effect shades if required) known as the natural layering concept, aiming to the same optimal esthetic integration and natural colour reproduction/emulation. The latest improvements appear all driven by the same view of improved reliability and clinical simplification.