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Sample records for varying shade tolerance

  1. Quantification of Shading Tolerability for Photovoltaic Modules

    NARCIS (Netherlands)

    Ziar, H.; Asaei, Behzad; Farhangi, Shahrokh; Isabella, O.; Korevaar, M.A.N.; Zeman, M.

    2017-01-01

    Despite several decades of research in the field of photovoltaic (PV) systems, shading tolerance has still not been properly addressed. PV modules are influenced by shading concerning many factors, such as number and configuration of cells in the module, electrical and thermal characteristics of

  2. Becoming less tolerant with age: sugar maple, shade, and ontogeny.

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    Sendall, Kerrie M; Lusk, Christopher H; Reich, Peter B

    2015-12-01

    Although shade tolerance is often assumed to be a fixed trait, recent work suggests ontogenetic changes in the light requirements of tree species. We determined the influence of gas exchange, biomass distribution, and self-shading on ontogenetic variation in the instantaneous aboveground carbon balance of Acer saccharum. We quantified the aboveground biomass distributions of 18 juveniles varying in height and growing in low light in a temperate forest understory in Minnesota, USA. Gas exchange rates of leaf and stem tissues were measured, and the crown architecture of each individual was quantified. The YPLANT program was used to estimate the self-shaded fraction of each crown and to model net leaf-level carbon gain. Leaf respiration and photosynthesis per gram of leaf tissue increased with plant size. In contrast, stem respiration rates per gram of stem tissue declined, reflecting a shift in the distribution of stem diameter sizes from smaller (with higher respiration) to larger diameter classes. However, these trends were outweighed by ontogenetic increases in self-shading (which reduces the net photosynthesis realized) and stem mass fraction (which increases the proportion of purely respiratory tissue) in terms of influence on net carbon exchange. As a result, net carbon gain per gram of aboveground plant tissue declined with increasing plant size, and the instantaneous aboveground light compensation point increased. When estimates of root respiration were included to model whole-plant carbon gain and light compensation points, relationships with plant size were even more pronounced. Our findings show how an interplay of gas exchange, self-shading, and biomass distribution shapes ontogenetic changes in shade tolerance.

  3. 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.

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

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    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

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

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    When subjected to shade, plants undergo rapid shoot elongation, which often makes them more prone to disease and mechanical damage. 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 ...

  6. 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.

  7. 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

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

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    Lienard, Jean; Florescu, Ionut; Strigul, Nikolay

    2015-01-01

    In this paper 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 tolerance driven succession in White Pine-Eastern Hemlock forests using computer simulations and analyzing approximated chronosequence data from the USDA FIA forest inventory. We describe this parameter across the last 50 years in the ecoregions of mainland USA, and demonstrate that it does not correlate with the usual macroscopic characteristics of stand age, biomass, basal area, and biodiversity measures. We characterize the dynamics of shade tolerance index using transition matrices and delimit geographical areas based on the relevance of shade tolerance to explain forest succession. We conclude that shade tolerance driven succession is linked to climatic variables and can be considered as a primary driving factor of forest dynamics mostly in central-north and northeastern areas in the USA. Overall, the shade tolerance index constitutes a new quantitative approach that can be used to understand and predict succession of forested ecosystems and biogeographic patterns.

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

    Directory of Open Access Journals (Sweden)

    Jean Lienard

    Full Text Available In this paper 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 tolerance driven succession in White Pine-Eastern Hemlock forests using computer simulations and analyzing approximated chronosequence data from the USDA FIA forest inventory. We describe this parameter across the last 50 years in the ecoregions of mainland USA, and demonstrate that it does not correlate with the usual macroscopic characteristics of stand age, biomass, basal area, and biodiversity measures. We characterize the dynamics of shade tolerance index using transition matrices and delimit geographical areas based on the relevance of shade tolerance to explain forest succession. We conclude that shade tolerance driven succession is linked to climatic variables and can be considered as a primary driving factor of forest dynamics mostly in central-north and northeastern areas in the USA. Overall, the shade tolerance index constitutes a new quantitative approach that can be used to understand and predict succession of forested ecosystems and biogeographic patterns.

  10. Photosynthesis, photoprotection, and growth of shade-tolerant tropical tree seedlings under full sunlight.

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    Krause, G Heinrich; Winter, Klaus; Matsubara, Shizue; Krause, Barbara; Jahns, Peter; Virgo, Aurelio; Aranda, Jorge; García, Milton

    2012-09-01

    High solar radiation in the tropics is known to cause transient reduction in photosystem II (PSII) efficiency and CO(2) assimilation in sun-exposed leaves, but little is known how these responses affect the actual growth performance of tropical plants. The present study addresses this question. Seedlings of five woody neotropical forest species were cultivated under full sunlight and shaded conditions. In full sunlight, strong photoinhibition of PSII at midday was documented for the late-successional tree species Ormosia macrocalyx and Tetragastris panamensis and the understory/forest gap species, Piper reticulatum. In leaves of O. macrocalyx, PSII inhibition was accompanied by substantial midday depression of net CO(2) assimilation. Leaves of all species had increased pools of violaxanthin-cycle pigments. Other features of photoacclimation, such as increased Chl a/b ratio and contents of lutein, β-carotene and tocopherol varied. High light caused strong increase of tocopherol in leaves of T. panamensis and another late-successional species, Virola surinamensis. O. macrocalyx had low contents of tocopherol and UV-absorbing substances. Under full sunlight, biomass accumulation was not reduced in seedlings of T. panamensis, P. reticulatum, and V. surinamensis, but O. macrocalyx exhibited substantial growth inhibition. In the highly shade-tolerant understory species Psychotria marginata, full sunlight caused strongly reduced growth of most individuals. However, some plants showed relatively high growth rates under full sun approaching those of seedlings at 40 % ambient irradiance. It is concluded that shade-tolerant tropical tree seedlings can achieve efficient photoacclimation and high growth rates in full sunlight.

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

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    Poorter, Lourens

    2009-03-01

    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 in forests under different climatic control. Here, adult leaf and metamer traits were measured for 39 tree species from a tropical moist semi-evergreen forest (1580 mm rain yr(-1)) and 41 species from a dry deciduous forest (1160 mm yr(-1)) in Bolivia. Twenty-six functional traits were measured and related to species regeneration light requirements.Adult leaf traits were clearly associated with shade tolerance. Different, rather than stronger, shade adaptations were found for moist compared with dry forest species. Shade adaptations exclusively found in the evergreen moist forest were related to tough and persistent leaves, and shade adaptations in the dry deciduous forest were related to high light interception and water use.These results suggest that, for forests differing in rainfall seasonality, there is a shift in the relative importance of functional leaf traits and performance trade-offs that control light partitioning. In the moist evergreen forest leaf traits underlying the growth-survival trade-off are important, whereas in the seasonally deciduous forest leaf traits underlying the growth trade-off between low and high light might become important.

  12. The effect of gamma radiation from sources "6"0Co of soybean for shade tolerant

    International Nuclear Information System (INIS)

    Lilik Harsanti; Yulidar

    2016-01-01

    Gamma rays are electromagnetic waves that have a very strong penetrating power. One of the sources of gamma rays is from "6"0Co. The gamma rays have strong penetration power can be used of plant breeding to create new genetic diversity in the make of high-yielding varieties. Irradiation of gamma rays at a dose of 300 gray and 400 gray on soybean Denna 1 seed varieties has been done, then it was planted as M.1 the plants look healthy and robust and strong stems. The parameters observed plant height, sum book leaf, sum seed, sum pod and Percentage plant to live shade tolerant. The parameters observed were good: plant height doze 300 Gy (37.76 cm) and 400 gray (33.03 cm) The number of branches with doze 300 Gy (1.75) and 400 Gy (1.95), number of pod with doze 300 Gy (26.25) and 400 Gy (24.72), number of seed with doze 300 Gy (35.55 kg) and 400 Gy (33.65 kg), number of Naut with doze 300 Gy (9.28) and 400 Gy (8.53) and the percentage of plants capable of shade tolerant with doze 300 Gy (85) and 400 Gy(75). In conclusion, selection mutant lines of soybeans shade tolerant at generation M1 and next generation. (author)

  13. 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

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

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    Thijs Leendert Pons

    2014-02-01

    Full Text Available Plant photosynthesis scales positively with growth irradiance. The carbon balance, defined here as the daily whole-plant gross CO2 assimilation (A partitioned in C available for growth and C required for respiration (R, is thus irradiance dependent. 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 towards 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 with a superior C

  15. Leaf non-structural carbohydrate allocation and C:N:P stoichiometry in response to light acclimation in seedlings of two subtropical shade-tolerant tree species.

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    Xie, Hongtao; Yu, Mukui; Cheng, Xiangrong

    2018-03-01

    that leaf morphological features of both E. sylvestris and I. henryi affected their corresponding leaf nutrient traits. These results improve our understanding of the dynamic balance between leaf NSCs and leaf C, N and P components in the nutritional metabolism of shade-tolerant plants. Two species of understory shade-tolerant plants responded differently to varying light intensities in terms of leaf non-structural carbohydrate allocation and the utilization of carbon, nitrogen and phosphorus to balance nutritional metabolism and adapt to environmental stress. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  16. Canopy gradients in leaf functional traits for species that differ in growth strategies and shade tolerance.

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    Coble, Adam P; Fogel, Marilyn L; Parker, Geoffrey G

    2017-10-01

    In temperate deciduous forests, vertical gradients in leaf mass per area (LMA) and area-based leaf nitrogen (Narea) are strongly controlled by gradients in light availability. While there is evidence that hydrostatic constraints on leaf development may diminish LMA and Narea responses to light, inherent differences among tree species may also influence leaf developmental and morphological response to light. We investigated vertical gradients in LMA, Narea and leaf carbon isotope composition (δ13C) for three temperate deciduous species (Carpinus caroliniana Walter, Fagus grandifolia Ehrh., Liriodendron tulipifera L.) that differed in growth strategy (e.g., indeterminate and determinate growth), shade tolerance and leaf area to sapwood ratio (Al:As). Leaves were sampled across a broad range of light conditions within three vertical layers of tree crowns to maximize variation in light availability at each height and to minimize collinearity between light and height. All species displayed similar responses to light with respect to Narea and δ13C, but not for LMA. Light was more important for gradients in LMA for the shade-tolerant (C. caroliniana) and -intolerant (L. tulipifera) species with indeterminate growth, and height (e.g., hydrostatic gradients) and light were equally important for the shade-tolerant (F. grandifolia) species with determinate growth. Fagus grandifolia had a higher morphological plasticity in response to light, which may offer a competitive advantage in occupying a broader range of light conditions throughout the canopy. Differences in responses to light and height for the taller tree species, L. tulipifera and F. grandifolia, may be attributed to differences in growth strategy or Al:As, which may alter morphological and functional responses to light availability. While height was important in F. grandifolia, height was no more robust in predicting LMA than light in any of the species, confirming the strong role of light availability in

  17. Large-scale biotic interaction effects - tree cover interacts with shade toler-ance to affect distribution patterns of herb and shrub species across the Alps

    DEFF Research Database (Denmark)

    Nieto-Lugilde, Diego; Lenoir, Jonathan; Abdulhak, Sylvain

    2012-01-01

    on the occurrence on light-demanding species via size-asymmetric competition for light, but a facilitative effect on shade-tolerant species. In order to compare the relative importance of tree cover, four models with different combinations of variables (climate, soil and tree cover) were run for each species. Then...... role. Results indicated that high tree cover causes range contraction, especially at the upper limit, for light-demanding species, whereas it causes shade-tolerant species to extend their range upwards and downwards. Tree cover thus drives plant-plant interactions to shape plant species distribution...

  18. Convergent evolution towards high net carbon gain efficiency contributes to the shade tolerance of palms (Arecaceae)

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    Ma, Ren Yi; Zhang, Jiao Lin; Cavaleri, Molly A.; Sterck, Frank; Strijk, J.S.; Cao, Kun Fang

    2015-01-01

    Most palm species occur in the shaded lower strata of tropical rain forests, but how their traits relate to shade adaptation is poorly understood. We hypothesized that palms are adapted to the shade of their native habitats by convergent evolution towards high net carbon gain efficiency (CGEn),

  19. Varying and unchanging whiteness on the wings of dusk-active and shade-inhabiting Carystoides escalantei butterflies.

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    Ge, Dengteng; Wu, Gaoxiang; Yang, Lili; Kim, Hye-Na; Hallwachs, Winnie; Burns, John M; Janzen, Daniel H; Yang, Shu

    2017-07-11

    Whiteness, although frequently apparent on the wings, legs, antennae, or bodies of many species of moths and butterflies, along with other colors and shades, has often escaped our attention. Here, we investigate the nanostructure and microstructure of white spots on the wings of Carystoides escalantei , a dusk-active and shade-inhabiting Costa Rican rain forest butterfly (Hesperiidae). On both males and females, two types of whiteness occur: angle dependent (dull or bright) and angle independent, which differ in the microstructure, orientation, and associated properties of their scales. Some spots on the male wings are absent from the female wings. Whether the angle-dependent whiteness is bright or dull depends on the observation directions. The angle-dependent scales also show enhanced retro-reflection. We speculate that the biological functions and evolution of Carystoides spot patterns, scale structures, and their varying whiteness are adaptations to butterfly's low light habitat and to airflow experienced on the wing base vs. wing tip.

  20. SUNLIT AND SHADED MAIZE CANOPY WATER LOSS UNDER VARIED WATER STRESS

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    Antonio Odair Santos

    1999-12-01

    Full Text Available ABSTRACT The precise estimation of transpiration from plant canopies is important for the monitoring of crop water use and management of many agricultural operations related to water use planning. The aim of this study was to estimate transpiration from sunlit and shaded fractions of a maize ( Zea mays L. canopy, using the Penman-Monteith energy balance equation with modifications introduced by Fuchs et al. (1987 and Fuchs & Cohen (1989. Estimated values were validated by a heat pulse system, which was used to measure stem sap flow and by a weighing lysimeter. A relationship between incident radiation and leaf stomatal conductance for critical levels of leaf water potential was used to estimate transpiration. Results showed that computed transpiration of the shaded canopy ranged from 27 to 45% of the total transpiration when fluctuations in atmospheric demand and the level of water stress were taken in account. Hourly and daily estimates of transpiration showed agreement with lysimeter and heat pulse measurements on the well-watered plots. For the water-limited plots the precision of the estimate decreased due to difficulties in simulating the canopy stomatal conductance.

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

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    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.

  2. Convergent Evolution towards High Net Carbon Gain Efficiency Contributes to the Shade Tolerance of Palms (Arecaceae.

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    Ren-Yi Ma

    Full Text Available Most palm species occur in the shaded lower strata of tropical rain forests, but how their traits relate to shade adaptation is poorly understood. We hypothesized that palms are adapted to the shade of their native habitats by convergent evolution towards high net carbon gain efficiency (CGEn, which is given by the maximum photosynthetic rate to dark respiration rate ratio. Leaf mass per area, maximum photosynthetic rate, dark respiration and N and P concentrations were measured in 80 palm species grown in a common garden, and combined with data of 30 palm species growing in their native habitats. Compared to other species from the global leaf economics data, dicotyledonous broad-leaved trees in tropical rainforest or other monocots in the global leaf economics data, palms possessed consistently higher CGEn, achieved by lowered dark respiration and fairly high foliar P concentration. Combined phylogenetic analyses of evolutionary signal and trait evolution revealed convergent evolution towards high CGEn in palms. We conclude that high CGEn is an evolutionary strategy that enables palms to better adapt to shady environments than coexisting dicot tree species, and may convey advantages in competing with them in the tropical forest understory. These findings provide important insights for understanding the evolution and ecology of palms, and for understanding plant shade adaptations of lower rainforest strata. Moreover, given the dominant role of palms in tropical forests, these findings are important for modelling carbon and nutrient cycling in tropical forest ecosystems.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    competition need not be size asymmetric, and suggest that tolerance to low light levels involves a reduction in phenotypic plasticity. Responses of the invasive A. philoxeroides to crowding may be an example of an invasive plant’s success in establishing dense stands of closely related individuals......, a shade‐tolerant invasive species. Stem fragments of A. philoxeroides were grown at either low or high densities (6 vs. 24 plants per pot) under three light levels (10%, 34%, and 100% full sun). After 8 weeks, survival was 31% lower in pots with a higher initial density. Both high density and low light...... levels reduced plant size substantially. Mean plant biomass ranged from 0.23 g in high‐density and low‐light pots to 4.41 g in low‐density and high‐light pots. There were no strong or significant effects of density or light level on size inequality of survivors. Most of the variation in allocation...

  4. An analytical model of stand dynamics as a function of tree growth, mortality and recruitment: the shade tolerance-stand structure hypothesis revisited.

    Science.gov (United States)

    Zavala, Miguel A; Angulo, Oscar; Bravo de la Parra, Rafael; López-Marcos, Juan C

    2007-02-07

    Light competition and interspecific differences in shade tolerance are considered key determinants of forest stand structure and dynamics. Specifically two main stand diameter distribution types as a function of shade tolerance have been proposed based on empirical observations. All-aged stands of shade tolerant species tend to have steeply descending, monotonic diameter distributions (inverse J-shaped curves). Shade intolerant species in contrast typically exhibit normal (unimodal) tree diameter distributions due to high mortality rates of smaller suppressed trees. In this study we explore the generality of this hypothesis which implies a causal relationship between light competition or shade tolerance and stand structure. For this purpose we formulate a partial differential equation system of stand dynamics as a function of individual tree growth, recruitment and mortality which allows us to explore possible individual-based mechanisms--e.g. light competition-underlying observed patterns of stand structure--e.g. unimodal or inverse J-shaped equilibrium diameter curves. We find that contrary to expectations interspecific differences in growth patterns can result alone in any of the two diameter distributions types observed in the field. In particular, slow growing species can present unimodal equilibrium curves even in the absence of light competition. Moreover, light competition and shade intolerance evaluated both at the tree growth and mortality stages did not have a significant impact on stand structure that tended to converge systematically towards an inverse J-shaped curves for most tree growth scenarios. Realistic transient stand dynamics for even aged stands of shade intolerant species (unimodal curves) were only obtained when recruitment was completely suppressed, providing further evidence on the critical role played by juvenile stages of tree development (e.g. the sampling stage) on final forest structure and composition. The results also point out the

  5. Crown traits of coniferous trees and their relation to shade tolerance can differ with leaf type: a biophysical demonstration using computed tomography scanning data

    OpenAIRE

    Dutilleul, Pierre; Han, Liwen; Valladares, Fernando; Messier, Christian

    2015-01-01

    Plant light interception and shade tolerance are intrinsically related in that they involve structural, morphological and physiological adaptations to manage light capture for photosynthetic utilization, in order to sustain survival, development and reproduction. At the scale of small-size trees, crown traits related to structural geometry of branching pattern and space occupancy through phyllotaxis can be accurately evaluated in 3D, using computed tomography (CT) scanning data. We demonstrat...

  6. Crown traits of coniferous trees and their relation to shade tolerance can differ with leaf type: A biophysical demonstration using computed tomography scanning data

    OpenAIRE

    Pierre eDutilleul; Liwen eHan; Fernando eValladeres; Christian eMessier; Christian eMessier

    2015-01-01

    Plant light interception and shade tolerance are intrinsically related in that they involve structural, morphological and physiological adaptations to manage light capture for photosynthetic utilization, in order to sustain survival, development and reproduction. At the scale of small-size trees, crown traits related to structural geometry of branching pattern and space occupancy through phyllotaxis can be accurately evaluated in 3D, using computed tomography (CT) scanning data. We demonstrat...

  7. 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

  8. 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

  9. Removal of nutrient limitations in forest gaps enhances growth rate and resistance to cavitation in subtropical canopy tree species differing in shade tolerance.

    Science.gov (United States)

    Villagra, Mariana; Campanello, Paula I; Montti, Lia; Goldstein, Guillermo

    2013-03-01

    A 4-year fertilization experiment with nitrogen (N) and phosphorus (P) was carried out in natural gaps of a subtropical forest in northeastern Argentina. Saplings of six dominant canopy species differing in shade tolerance were grown in five control and five N + P fertilized gaps. Hydraulic architectural traits such as wood density, the leaf area to sapwood area ratio (LA : SA), vulnerability to cavitation (P50) and specific and leaf-specific hydraulic conductivity were measured, as well as the relative growth rate, specific leaf area (SLA) and percentage of leaf damage by insect herbivores. Plant growth rates and resistance to drought-induced embolisms increased when nutrient limitations were removed. On average, the P50 of control plants was -1.1 MPa, while the P50 of fertilized plants was -1.6 MPa. Wood density and LA : SA decreased with N + P additions. A trade-off between vulnerability to cavitation and efficiency of water transport was not observed. The relative growth rate was positively related to the total leaf surface area per plant and negatively related to LA : SA, while P50 was positively related to SLA across species and treatments. Plants with higher growth rates and higher total leaf area in fertilized plots were able to avoid hydraulic dysfunction by becoming less vulnerable to cavitation (more negative P50). Two high-light-requiring species exhibited relatively low growth rates due to heavy herbivore damage. Contrary to expectations, shade-tolerant plants with relatively high resistance to hydraulic dysfunction and reduced herbivory damage were able to grow faster. These results suggest that during the initial phase of sapling establishment in gaps, species that were less vulnerable to cavitation and exhibited reduced herbivory damage had faster realized growth rates than less shade-tolerant species with higher potential growth rates. Finally, functional relationships between hydraulic traits and growth rate across species and treatments

  10. 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

  11. Selecting Landscape Plants: Shade Trees

    OpenAIRE

    Relf, Diane; Appleton, Bonnie Lee, 1948-2012; Close, David

    2015-01-01

    Because of the permanency of trees and their importance in the landscape, care must be taken to select the best species for each situation. This publication goes over how to choose landscape trees that are shade tolerant.

  12. Crown traits of coniferous trees and their relation to shade tolerance can differ with leaf type: a biophysical demonstration using computed tomography scanning data.

    Science.gov (United States)

    Dutilleul, Pierre; Han, Liwen; Valladares, Fernando; Messier, Christian

    2015-01-01

    Plant light interception and shade tolerance are intrinsically related in that they involve structural, morphological and physiological adaptations to manage light capture for photosynthetic utilization, in order to sustain survival, development and reproduction. At the scale of small-size trees, crown traits related to structural geometry of branching pattern and space occupancy through phyllotaxis can be accurately evaluated in 3D, using computed tomography (CT) scanning data. We demonstrate this by scrutinizing the crowns of 15 potted miniature conifers of different species or varieties, classified in two groups based on leaf type (10 needlelike, 5 scalelike); we also test whether mean values of crown traits measured from CT scanning data and correlations with a shade tolerance index (STI) differ between groups. Seven crown traits, including fractal dimensions (FD1: smaller scales, FD2: larger scales) and leaf areas, were evaluated for all 15 miniature conifers; an average silhouette-to-total-area ratio was also calculated for each of the 10 needlelike-leaf conifers. Between-group differences in mean values are significant (P conifers with scalelike leaves, which had lower STI and higher FD1 on average in our study; the positive correlation between STI and ĀD is significant (P < 0.05) for the scalelike-leaf group, and very moderate for the needlelike-leaf one. A contrasting physical attachment of the leaves to branches may explain part of the between-group differences. Our findings open new avenues for the understanding of fundamental plant growth processes; the information gained could be included in a multi-scale approach to tree crown modeling.

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

    Science.gov (United States)

    Field, Katie J; George, Rachel; Fearn, Brian; Quick, W Paul; Davey, Matthew P

    2013-01-01

    "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.

  14. Crown traits of coniferous trees and their relation to shade tolerance can differ with leaf type: a biophysical demonstration using computed tomography scanning data

    Science.gov (United States)

    Dutilleul, Pierre; Han, Liwen; Valladares, Fernando; Messier, Christian

    2015-01-01

    Plant light interception and shade tolerance are intrinsically related in that they involve structural, morphological and physiological adaptations to manage light capture for photosynthetic utilization, in order to sustain survival, development and reproduction. At the scale of small-size trees, crown traits related to structural geometry of branching pattern and space occupancy through phyllotaxis can be accurately evaluated in 3D, using computed tomography (CT) scanning data. We demonstrate this by scrutinizing the crowns of 15 potted miniature conifers of different species or varieties, classified in two groups based on leaf type (10 needlelike, 5 scalelike); we also test whether mean values of crown traits measured from CT scanning data and correlations with a shade tolerance index (STI) differ between groups. Seven crown traits, including fractal dimensions (FD1: smaller scales, FD2: larger scales) and leaf areas, were evaluated for all 15 miniature conifers; an average silhouette-to-total-area ratio was also calculated for each of the 10 needlelike-leaf conifers. Between-group differences in mean values are significant (P < 0.05) for STI, FD1, FD2, and the average leaf area displayed (ĀD). Between-group differences in sign and strength of correlations are observed. For example, the correlation between STI and FD1 is negative and significant (P < 0.10) for the needlelike-leaf group, but is positive and significant (P < 0.05) for the miniature conifers with scalelike leaves, which had lower STI and higher FD1 on average in our study; the positive correlation between STI and ĀD is significant (P < 0.05) for the scalelike-leaf group, and very moderate for the needlelike-leaf one. A contrasting physical attachment of the leaves to branches may explain part of the between-group differences. Our findings open new avenues for the understanding of fundamental plant growth processes; the information gained could be included in a multi-scale approach to tree crown

  15. Crown traits of coniferous trees and their relation to shade tolerance can differ with leaf type: A biophysical demonstration using computed tomography scanning data

    Directory of Open Access Journals (Sweden)

    Pierre eDutilleul

    2015-03-01

    Full Text Available Plant light interception and shade tolerance are intrinsically related in that they involve structural, morphological and physiological adaptations to manage light capture for photosynthetic utilization, in order to sustain survival, development and reproduction. At the scale of small-size trees, crown traits related to structural geometry of branching pattern and space occupancy through phyllotaxis can be accurately evaluated in 3D, using computed tomography (CT scanning data. We demonstrate this by scrutinizing the crowns of 15 potted miniature conifers of different species or varieties, classified in two groups based on leaf type (10 needlelike, 5 scalelike; we also test whether mean values of crown traits measured from CT scanning data and correlations with a shade tolerance index (STI differ between groups. Seven crown traits, including fractal dimensions (FD1: smaller scales, FD2: larger scales and leaf areas, were evaluated for all 15 miniature conifers; an average silhouette-to-total-area ratio was also calculated for each of the 10 needlelike-leaf conifers. Between-group differences in mean values are significant (P < 0.05 for STI, FD1, FD2, and average leaf area displayed (A_D. Between-group differences in sign and strength of correlations are observed. For example, the correlation between STI and FD1 is negative and significant (P < 0.10 for the needlelike-leaf group, but is positive and significant (P < 0.05 for the miniature conifers with scalelike leaves, which had lower STI and higher FD1 on average in our study; the positive correlation between STI and A_D is significant (P < 0.05 for the scalelike-leaf group, and very moderate for the needlelike-leaf one. A contrasting physical attachment of leaves to branches may explain part of the between-group differences. Our findings open new avenues for the understanding of fundamental plant growth processes; the information gained could be included in a multi-scale approach to tree crown

  16. 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.

  17. Photosynthetic responses to understory shade and elevated carbon dioxide concentration in 4 northern hardwood tree species

    International Nuclear Information System (INIS)

    Sefcik, L.T.; Zak, D.R.; Ellsworth, D.S.

    2006-01-01

    Stimulation of photosynthesis in response to elevated carbon dioxide (CO 2 ) varies among tree species and species groups. In this study, seedling responses to elevated atmospheric carbon dioxide (CO 2 ) concentrations and solar irradiance over 2 growing seasons were investigated for shade tolerant Acer saccharum Marsh.; Fagus grandifolia J.F. Ehrh; and shade-intolerant Prunus serotina. Seedlings were exposed to a combination of elevated and ambient concentrations of CO 2 and understory shade in open-top chambers placed in a forest understory. It was observed that the elevated CO 2 treatment increased mean light-saturated net photosynthetic rates by 63 per cent in the shade-tolerant species and 67 per cent in the shade-intolerant species. When measured at the elevated CO 2 , long-term enhancement of photosynthesis was 10 per cent lower than the instantaneous enhancement observed in ambient-CO 2 -grown plants. As the growth irradiance increased, proportional enhancement due to elevated CO 2 decreased from 97 per cent for plants grown in deep shade to 47 per cent for plants grown in moderate shade. Results indicated that in nitrogen (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, due to greater down-regulation. It was concluded that if elevated CO 2 levels promote the survival of shade-intolerant species in dim understory light, the future composition and dynamics of successional forest communities may be altered. 70 refs., 2 tabs., 3 figs

  18. 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 P 700 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.

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

    NARCIS (Netherlands)

    Gommers, C.M.M.

    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

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

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Esbensen, Thomas; Stoustrup, Jakob

    2011-01-01

    High performance and reliability are required for wind turbines to be competitive within the energy market. To capture their nonlinear behavior, wind turbines are often modeled using parameter-varying models. In this paper we design and compare multiple linear parameter-varying (LPV) controllers,...

  1. MicroRNA Expression Varies according to Glucose Tolerance, Measurement Platform, and Biological Source

    Directory of Open Access Journals (Sweden)

    S. Dias

    2017-01-01

    Full Text Available Dysregulated microRNA (miRNA expression is observed during type 2 diabetes (T2D, although the consistency of miRNA expression across measurement platform and biological source is uncertain. Here we report miRNA profiling in the whole blood and serum of South African women with different levels of glucose tolerance, using next generation sequencing (NGS and quantitative real time PCR (qRT-PCR. Whole blood-derived miRNAs from women with newly diagnosed T2D (n=4, impaired glucose tolerance (IGT (n=4, and normal glucose tolerance (NGT (n=4 were subjected to NGS, whereafter transcript levels of selected miRNAs were quantified in the whole blood and serum of these women using qRT-PCR. Of the five significantly differentially expressed miRNAs identified by NGS, only the directional increase of miR-27b in women with IGT compared to NGT was confirmed in whole blood and serum, using qRT-PCR. Functional enrichment of miR-27b gene targets identified biological pathways associated with glucose transport and insulin regulation. In conclusion, this study showed poor correlation in miRNA expression profiled using NGS and qRT-PCR and in whole blood and serum. The consistent increased expression of miR-27b in women with IGT compared to NGT across measurement platform and biological source holds potential as a biomarker for risk stratification in our population.

  2. Biofilm-forming bacteria with varying tolerance to peracetic acid from a paper machine.

    Science.gov (United States)

    Rasimus, Stiina; Kolari, Marko; Rita, Hannu; Hoornstra, Douwe; Salkinoja-Salonen, Mirja

    2011-09-01

    Biofilms cause runnability problems in paper machines and are therefore controlled with biocides. Peracetic acid is usually effective in preventing bulky biofilms. This study investigated the microbiological status of a paper machine where low concentrations (≤ 15 ppm active ingredient) of peracetic acid had been used for several years. The paper machine contained a low amount of biofilms. Biofilm-forming bacteria from this environment were isolated and characterized by 16S rRNA gene sequencing, whole-cell fatty acid analysis, biochemical tests, and DNA fingerprinting. Seventy-five percent of the isolates were identified as members of the subclades Sphingomonas trueperi and S. aquatilis, and the others as species of the genera Burkholderia (B. cepacia complex), Methylobacterium, and Rhizobium. Although the isolation media were suitable for the common paper machine biofoulers Deinococcus, Meiothermus, and Pseudoxanthomonas, none of these were found, indicating that peracetic acid had prevented their growth. Spontaneous, irreversible loss of the ability to form biofilm was observed during subculturing of certain isolates of the subclade S. trueperi. The Sphingomonas isolates formed monoculture biofilms that tolerated peracetic acid at concentrations (10 ppm active ingredient) used for antifouling in paper machines. High pH and low conductivity of the process waters favored the peracetic acid tolerance of Sphingomonas sp. biofilms. This appears to be the first report on sphingomonads as biofilm formers in warm water using industries.

  3. 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

  4. 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

  5. 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.

  6. Uniform versus asymmetric shading mediates crown recession in conifers.

    Directory of Open Access Journals (Sweden)

    Amanda L Schoonmaker

    Full Text Available In this study we explore the impact of asymmetrical vs. uniform crown shading on the mortality and growth of upper and lower branches within tree crowns, for two conifer species: shade intolerant lodgepole pine (Pinus contorta and shade tolerant white spruce (Picea glauca. We also explore xylem hydraulics, foliar nutrition, and carbohydrate status as drivers for growth and expansion of the lower and upper branches in various types of shading. This study was conducted over a two-year period across 10 regenerating forest sites dominated by lodgepole pine and white spruce, in the lower foothills of Alberta, Canada. Trees were assigned to one of four shading treatments: (1, complete uniform shading of the entire tree, (2 light asymmetric shading where the lower 1/4-1/3 of the tree crown was shaded, (3 heavy asymmetric shading as in (2 except with greater light reduction and (4 control in which no artificial shading occurred and most of the entire crown was exposed to full light. Asymmetrical shading of only the lower crown had a larger negative impact on the bud expansion and growth than did uniform shading, and the effect was stronger in pine relative to spruce. In addition, lower branches in pine also had lower carbon reserves, and reduced xylem-area specific conductivity compared to spruce. For both species, but particularly the pine, the needles of lower branches tended to store less C than upper branches in the asymmetric shade, which could suggest a movement of reserves away from the lower branches. The implications of these findings correspond with the inherent shade tolerance and self-pruning behavior of these conifers and supports a carbon based mechanism for branch mortality--mediated by an asymmetry in light exposure of the crown.

  7. 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

  8. 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

    In a field experiment, winter wheat (Triticum aestivum L.) cultivars Yangmai 158 (YM 158, shading tolerant) and Yangmai 11 (YM 11, shading-sensitive) were subjected to shading between jointing and maturity. Three shading treatments were applied, i.e. 92% (S1), 85% (S2) and 77% (S3) of full...... 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...... the flag leaf, as in most cases Pn of the third and the penultimate leaves were found to increase under shading treatments. Shading increased the redistribution of dry matter from vegetative organs into grains. The responses of the morphological and physiological traits to shading are discussed in relation...

  9. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    is linked to a different set of circumstances than the ones suggested by existing models in contemporary democratic theory. Reorienting the discussion of tolerance, the book raises the question of how to disclose new possibilities within our given context of affect and perception. Once we move away from......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...

  10. 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....

  11. Ethnicity and perception of dental shade esthetics.

    Science.gov (United States)

    Niaz, Muhammad Omar; Naseem, Mustafa; Elcock, Claire

    2015-01-01

    To determine whether or not people from different ethnic backgrounds have different attitudes towards dental esthetics and chose different dental appearances in terms of tooth shade, and to determine whether the dental professional's choice and the individual's own choice have any relationship with what the individual ideally perceives as esthetically pleasing. For this cross-sectional analytical study, 120 volunteer students from the University of Sheffield (excepting dental students) from various ethnic backgrounds, of different ages, of both genders, and with varying degree/educational levels were recruited from the campus. The volunteers were asked to complete a questionnaire containing 9 adapted attitudinal statements regarding positive or negative dental esthetic perceptions in terms of tooth shade, with responses on a 5-point Likert scale from "Entirely agree" to "Entirely disagree". Scores for all attitudinal statements were summed up to give an attitudinal score. The participants' ideal, perceived, and actual (self-assessed and investigatorassessed) tooth shade was also determined using a shade guide and a facial mirror. No association between ethnicity and attitudinal score was found. However, statistically significant associations were found between the participants' degree/educational level (P=0.004, 95% Confidence Interval (CI)=-4.18 to -0.82) and their ideal tooth shade value (P=0.038, 95% CI=-3.53 to -0.11). There were strong correlations between self-assessed and professionally assessed tooth shade value in all ethnic groups, with Spearman's rank correlation coefficient (rho) being ρ>0.6. Regarding ideally desired and perceived tooth shade value, weak correlations were found in all ethnic groups (Spearman's rho being ρethnicity and attitude towards dental esthetics with regard to tooth shade, both ethnicity and dental esthetics are very diverse terms with multiple dimensions, each of which needs further investigation with regard to their mutual

  12. Effect of shade on photosynthetic pigments in the tropical root crops: yam, taro, tannia, cassava and sweet potato

    International Nuclear Information System (INIS)

    Johnston, M.; Onwueme, I.C.

    1998-01-01

    Plants of yam, taro, tannia, cassava and sweet potato were raised under shade or in full sunlight and the effect of shade on leaf chlorophyll and carotenoids was examined to determine and compare the relative shade tolerance and adaptability of the var ious species. All five species of root crops adapted to shade. The chlorophyll concentration was higher, while the chlorophyll a:b ratio, carotenoids per unit chlorophyll and the weight per unit area of leaf were lower in the shade than in the sun in yam, tannia, taro, cassava and sweet potato. All species had larger leaves and more chlorophyll per leaf in the shade. The extent of the changes, however, differed between species. The aroids (taro and tannia) appeared to be shade-tolerant species as their chlorophyll a:b ratios changed less than those of the other species in the shade, suggesting that their light-harvesting systems may be normally adapted to shade conditions. Taro and tannia also adapted to shade by a greater proportional increase in leaf size, a smaller reduction in leaf weight per unit area and a greater proportional increase in chlorophyll and carotenoids per leaf than the other species. Yam compensated for shade by having a large proportional increase in leaf size and appeared to be moderately tolerant of shade. Sweet potato and cassava appeared to be the least tolerant of shade of the major tropical root crops. (author)

  13. 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 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.

  14. Shade response of a full size TESSERA module

    Science.gov (United States)

    Slooff, Lenneke H.; Carr, Anna J.; de Groot, Koen; Jansen, Mark J.; Okel, Lars; Jonkman, Rudi; Bakker, Jan; de Gier, Bart; Harthoorn, Adriaan

    2017-08-01

    A full size TESSERA shade tolerant module has been made and was tested under various shadow conditions. The results show that the dedicated electrical interconnection of cells result in an almost linear response under shading. Furthermore, the voltage at maximum power point is almost independent of the shadow. This decreases the demand on the voltage range of the inverter. The increased shadow linearity results in a calculated increase in annual yield of about 4% for a typical Dutch house.

  15. 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.

  16. Tints, Shades and Frost

    Science.gov (United States)

    Sterling, Joan

    2009-01-01

    This article describes a classroom art project inspired by the work of Robert Frost, one of the most acclaimed and beloved American poets of all time. Using tints and shades in a composition, this project demonstrates how quality literature may be incorporated into elementary art lessons in a very useful way, making art an important complement to…

  17. 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.

  18. 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.

  19. Salinity tolerance in barley (hordeum vulgare l.): effects of varying NaCl, K/sup +/ Na/sup +/ and NaHCO/sub 3/ levels on cultivars differing in tolerance

    International Nuclear Information System (INIS)

    Mahmood, K.

    2011-01-01

    Although barley (Hordeum vulgare L.) is regarded as salt tolerant among crop plants, its growth and plant development is severely affected by ionic and osmotic stresses in salt-affected soils. To elucidate the tolerance mechanism, growth and ion uptake of three barley cultivars, differing in salt tolerance, were examined under different levels of NaCl, K/sup +/ Na/sup +/ and NaHCO/sub 3/ in the root medium. The cultivars differed greatly in their responses to varying root medium conditions. Plant growth was more adversely affected by NaHCO/sub 3/ than NaCl. In general, biomass yields were comparable under control and 100 mM NaCl. However, growth of all three cultivars was significantly inhibited by NaHCO/sub 3/ even at low concentration (10 mM). Improved K/sup +/ supply in saline medium increased K/sup +/ uptake and growth of less tolerant cultivars. K/sup +/ uptake was more adversely affected by NaHCO/sub 3/ than NaCl salinity. Selective K/sup +/ uptake and lower Cl/sup -/ in shoots seemed to be associated with the growth responses. K application would help better growth of these cultivars on K-deficient saline-sodic soils and under irrigation with poor quality water having high Residual Sodium Carbonate (RSC) and/or Sodium Adsorption Ratio (SAR). (author)

  20. 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

  1. 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)

  2. Are serum adiponectin concentrations in a population sample of 64-year-old Caucasian women with varying glucose tolerance associated with ultrasound-assessed atherosclerosis?

    Science.gov (United States)

    Behre, C J; Brohall, G; Hulthe, J; Wikstrand, J; Fagerberg, B

    2006-09-01

    To examine whether serum adiponectin concentrations were associated with subclinical atherosclerosis assessed as intima media thickness (IMT) in the carotid arteries in Caucasian women with varying degrees of glucose tolerance. From a population-based cohort of 64-year-old Swedish women, 533 subjects with type 2 diabetes (DM2, n=177), impaired glucose tolerance (IGT; n=178) or normal glucose tolerance (NGT, n=178) were recruited. Anthropometrics, usual cardiovascular risk factors were examined and ultrasound examination of the carotid arteries was performed. Women with low adiponectin concentrations were characterized by thick IMT, higher prevalence of DM2, history of previous myocardial infarction, angina pectoris, anti-hypertensive treatment and high body mass index (BMI), waist circumference, plasma insulin, serum triglycerides, fasting glucose, HbA1c, and low serum HDL cholesterol levels. Carotid IMT correlated with HbA1c (r=0.24, PDM2 (r=0.16, P<0.001), systolic blood pressure (r=0.16, P<0.001), blood glucose (r=0.16, P<0.001), triglycerides (r=0.15, P<0.001), and reversely to adiponectin (r=-0.11, P=0.01), HDL cholesterol (r=-0.13, P=0.004), and alcohol intake (r=-0.087, P<0.05). A more detailed analysis of underlying associations was difficult due to a high co-linearity between these variable. Low serum adiponectin concentrations were associated with increased carotid artery IMT, and several risk factors for cardiovascular diseases, mainly those constituting the metabolic syndrome.

  3. Abiotic alterations caused by forest fragmentation affect tree regeneration: a shade and drought tolerance gradient in the remnants of Coastal Maulino Forest Alteraciones abióticas causadas por la fragmentación del bosque afectan la regeneración arbórea: un gradiente de tolerancia a la sombra y la sequía en los remanentes del Bosque Maulino Costero

    Directory of Open Access Journals (Sweden)

    PABLO C GUERRERO

    2009-01-01

    Full Text Available Plant regeneration is strongly determined by light and soil moisture differences between habitáis; both variables are modified by large-scale forest fragmentation. Several studies have indicated this alteration as the mechanism involved in tropical forest community change. The effects of fragmentation may be much more severe in Mediterranean and deciduous forests, because plant species in these forests show a stress tolerance tradeoff between shade and drought. Our study was performed in the deciduous fragmented Coastal Maulino Forest: Reserva Nacional Los Queules (RNLQ and surrounding small fragments. We hypothesised that Aristotelia chilensis (shade intolerant but drought tolerant should increase its regeneration in small patches as a consequence of the change in habitat suitability (i.e. luminous and drier, while Cryptocarya alba (shade tolerant but drought intolerant should have less regeneration in small fragments. We also expected that Nothofagus glauca and N. obliqua, which have shade and drought tolerances intermedíate between A. chilensis and C. alba, should respond less to forest fragmentation. We used two estimations of plant regeneration: (i seedling and sapling densities via field observations and (ii seed germination and seedling establishment via a field-based experiment. Natural regeneration patterns of C. alba indicated a depressed regeneration within small forest fragments compared to RNLQ, although experimental germination, establishment and recruitment proportions did not vary between habitáis. In contrast, A. chilensis regeneration was favored by forest fragmentation, with increased seedling and sapling densities and germination in small forest fragments. Both N. glauca and N. obliqua were less affected by forest fragmentation in their natural and experimental regeneration. This study highlights the relevance of studying changes in abiotic factors as a consequence of human activities, and considering safe sites (defined

  4. Photochemical efficiency of PSII and photoprotective pigments in seedlings and adults of two Proteaceae with different shade tolerance from the Chilean temperate rain forest Eficiencia fotoquímica del PSII y pigmentos fotoprotectores en plántulas y adultos de dos Proteáceas con diferente tolerancia a la sombra del bosque lluvioso templado chileno

    Directory of Open Access Journals (Sweden)

    MIREN ALBERDI

    2009-01-01

    Full Text Available The seasonal variation in energy quenching parameters of photosystem II and photoprotective pigments were studied in seedlings and adults of two Proteaceae: a shade-intolerant species (Embotrium coccineum J.R. et G. Forster and a shade-tolerant species (Lomatia ferruginea (Cav. R. Br.. We postúlate that the shade intolerant species favors photochemical energy driven processes (mainly C0(2 assimilation while the shade tolerant species exhibits higher non-photochemical energy dissipation under unfavorable conditions. Moreover, the shade tolerant species presents lower seasonal variations in these parameters that the shade intolerant species. Differences in energy dissipation should be more evident in seedlings than adults because of their contrasting light environments and temperatures are more evident at this stage. Their maximal photochemical efficiency (Fv/Fm was in the range 0.70-0.83. The effective photochemical efficiency (PSII, photochemical quenching (qP, and electrón transport rate (ETR were higher in seedlings of E. coccineum than in seedlings of L. ferruginea. Adults showed higher photochemical energy quenching parameters than seedlings. Non-photochemical quenching (NPQ was frequently similar between daily periods, seasons, species, and developmental stages, with the exception of the lowest non-photochemical quenching in seedlings of E. coccineum in summer. Seedlings and adults showed a larger xanthophyll cycle pool contení at midday in summer than in winter, while the pool of antheraxanthin + zeaxanthin was always higher at midday. Lutein increased the most during summer. Thus, E. coccineum seedlings and adults maintained high photosynthesis, a higher fraction of open reaction centres, and higher ETR than the shade tolerant species. These differences are consistent with the ecological functions of both species: a pioneer character, higher growth rate, and wide altitudinal and latitudinal distribution of E. coccineum compared to L

  5. 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

  6. 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

    2018-01-01

    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 m 2 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.

  7. 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.

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

    OpenAIRE

    Paulo Roberto de Lima Meirelles; Erikelly Aline Ribeiro de Santana; Guilherme Mendes Machado Franco de Arruda; Ciniro Costa; Marina Gabriela Berchiol da Silva

    2013-01-01

    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 iss...

  9. Growth characteristics and nutrient content of some herbaceous species under shade and fertilization

    Energy Technology Data Exchange (ETDEWEB)

    Koukoura, Z.; Kyriazopoulos, A. P.; Parissi, Z. M.

    2009-07-01

    Herbage production and nutrient content are affected by light interception and soil fertility. The objective of this study was to assess the effects of artificial shade and fertilization on herbage production, growth characteristics, and nutrient content of the grass species Dactylis glomerata and Festuca ovina, and the legume species Trifolium subterraneum and Medicago lupulina. Each plant species was placed under three shading treatments of 90% (heavy shade), 50% (moderate shade) and 0% (control). Fertilization (225 kg ha{sup -}1 N, 450 kg ha{sup -}1 P, and 225 kg ha{sup -}1 K) was applied to half of the pots of every species and shading treatment. Reduced light intensity (90% shading) significantly lowered herbage production from 18% for F. ovina to 48% for D. glomerata and decreased the root:shoot (R/S) ratio of all species but the moderate reduction of light intensity (50%) did not affect R/S ratio and herbage production of the grasses and M. lupulina, while it resulted in an increase of the production of T. subterraneum by 10.5%. Reduced light intensity increased by 25% on average, the crude protein concentration of the grass species while moderate shading did not affect the crude protein concentration of T. subterraneum. Fertilization increased herbage production from 16% for F. ovina to 59% for D. glomerata and ameliorated its nutrient content. Among the tested species, D. glomerata and T. subterraneum demonstrated the highest shade tolerance and could be incorporated into silvopastoral systems of the Mediterranean region. (Author)

  10. Efficient Methods for Fast Shading

    Directory of Open Access Journals (Sweden)

    ROMANYUK, A.

    2008-06-01

    Full Text Available On devices without battery consuming and specialized hardware for rendering, it is important to improve the speed and quality so that these methods are suitable for real-time rendering. Furthermore such algorithms are needed on the coming multicore architectures. We show how the methods by Gouraud and Phong, the commonly most used methods for shading, can be improved and made faster for both software rendering as well as simple low energy consuming hardware implementations. Moreover, this paper summarizes the authors' achievements in increasing shading speed and performance and a Bidirectional Reflectance Distribution Function is simplified for faster computing and hardware implementation.

  11. 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.

  12. Esthetics and shade communication: a practical approach.

    Science.gov (United States)

    Hegenbarth, Ernst A

    2006-01-01

    Accurate shade analysis and communication represent one of the biggest challenges in restorative and esthetic dentistry today, especially in light of the rapidly increasing array of ceramic materials available. Traditional methods of shade analysis have relied upon the use of conventional shade guides or, more recently, digital shade measurement. In this article, the author examines the advantages and disadvantages of traditional shade analysis; reviews principles for optimizing the evaluation process, including information regarding the scientific basis of general color science, optics, and aspects of material science; and proposes a six-step approach to shade analysis in which less emphasis is placed on shade guide samples in favor of natural internal structures and surface properties and their replication in different dentin, enamel, transparent, and colored translucent, as well as fluorescent and opalescent, ceramics.

  13. 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.

  14. 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.

  15. Ireland, Shaded Relief and Colored Height

    Science.gov (United States)

    2005-01-01

    The island of Ireland comprises a large central lowland of limestone with a relief of hills surrounded by a discontinuous border of coastal mountains which vary greatly in geological structure. The mountain ridges of the south are composed of old red sandstone separated by limestone river valleys. Granite predominates in the mountains of Galway, Mayo and Donegal in the west and north-west and in Counties Down and Wicklow on the east coast, while a basalt plateau covers much of the north-east of the country. The central plain, which is broken in places by low hills, is extensively covered with glacial deposits of clay and sand. It has considerable areas of bog and numerous lakes. The island has seen at least two general glaciations and everywhere ice-smoothed rock, mountain lakes, glacial valleys and deposits of glacial sand, gravel and clay mark the passage of the ice. Two visualization methods were combined to produce this 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 additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Geospatial-Intelligence Agency

  16. Shading Ratio Impact on Photovoltaic Modules and Correlation with Shading Patterns

    Directory of Open Access Journals (Sweden)

    Alonso Gutiérrez Galeano

    2018-04-01

    Full Text Available This paper presents the study of a simplified approach to model and analyze the performance of partially shaded photovoltaic modules using the shading ratio. This approach integrates the characteristics of shaded area and shadow opacity into the photovoltaic cell model. The studied methodology is intended to improve the description of shaded photovoltaic systems by specifying an experimental procedure to quantify the shadow impact. Furthermore, with the help of image processing, the analysis of the shading ratio provides a set of rules useful for predicting the current–voltage behavior and the maximum power points of shaded photovoltaic modules. This correlation of the shading ratio and shading patterns can contribute to the supervision of actual photovoltaic installations. The experimental results validate the proposed approach in monocrystalline and polycrystalline technologies of solar panels.

  17. External shading devices for energy efficient building

    Science.gov (United States)

    Shahdan, M. S.; Ahmad, S. S.; Hussin, M. A.

    2018-02-01

    External shading devices on a building façade is an important passive design strategy as they reduce solar radiation. Although studies have proven the benefits of external shading devices, many are designed solely for aesthetic purposes without fully considering its high potential to reduce solar radiation and glare. Furthermore, explorations into shading devices by the design team are mostly left too late in the design development phases. Hence, the paper looks into the effectiveness of external shading devices on a building towards more energy efficient building. The study aims to analyse the effects of various configurations of external shading devices towards the energy consumption of a case study building based on computer simulations. This study uses Building Information Modelling (BIM) through Autodesk Revit software as simulation tool. The constant variables for the simulation are the orientation of the building, types of glazing used by the building and the internal loads of the building. Whereas, the manipulated variable is the types of shading device used. The data were sorted according to the categories and translated into a chart. Analysis of the findings indicate that shading devices with different configurations show significant results in the energy consumption and the best configuration is the egg-crate shading devices. The study recommends that the consideration for shading device as a passive design strategy needs to be developed at the early stage of the building design.

  18. Effects of a shade-matching light and background color on reliability in tooth shade selection.

    Science.gov (United States)

    Najafi-Abrandabadi, Siamak; Vahidi, Farhad; Janal, Malvin N

    2018-01-01

    The purpose of this study was to evaluate the effects of a shade-matching light (Rite-Lite-2, AdDent) and different viewing backgrounds on reliability in a test of shade tab matching. Four members of the Prosthodontic faculty matched 10 shade tabs selected for a range of shades against the shade guide. All raters were tested for color blindness and were calibrated prior to the study. Matching took place under four combinations of conditions: with operatory light or the shade-matching light, and using either a pink or a blue background. Reliability was quantified with the kappa statistic, separately for agreement of value, hue, and chroma for each shade tab. In general, raters showed fair to moderate levels of agreement when judging the value of the shade tabs, but could not agree on the hue and chroma of the stimuli. The pink background led to higher levels of agreement than the blue background, and the shade-matching light improved agreement when used in conjunction with the pink but not the blue background. Moderate levels of agreement were found in matching shade tab value. Agreement was generally better when using the pink rather than the blue background, regardless of light source. The use of the shade-matching light tended to amplify the advantage of the pink background.

  19. 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 (Preliability (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.

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

    Directory of Open Access Journals (Sweden)

    Sjarifudin Firza Utama

    2014-03-01

    Full Text Available 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°.

  1. Mixed-conifer forests of central Oregon: effects of logging and fire exclusion vary with environment.

    Science.gov (United States)

    Merschel, Andrew G; Spies, Thomas A; Heyerdahl, Emily K

    Twentieth-century land management has altered the structure and composition of mixed-conifer forests and decreased their resilience to fire, drought, and insects in many parts of the Interior West. These forests occur across a wide range of environmental settings and historical disturbance regimes, so their response to land management is likely to vary across landscapes and among ecoregions. However, this variation has not been well characterized and hampers the development of appropriate management and restoration plans. We identified mixed-conifer types in central Oregon based on historical structure and composition, and successional trajectories following recent changes in land use, and evaluated how these types were distributed across environmental gradients. We used field data from 171 sites sampled across a range of environmental settings in two subregions: the eastern Cascades and the Ochoco Mountains. We identified four forest types in the eastern Cascades and four analogous types with lower densities in the Ochoco Mountains. All types historically contained ponderosa pine, but differed in the historical and modern proportions of shade-tolerant vs. shade-intolerant tree species. The Persistent Ponderosa Pine and Recent Douglas-fir types occupied relatively hot–dry environments compared to Recent Grand Fir and Persistent Shade Tolerant sites, which occupied warm–moist and cold–wet environments, respectively. Twentieth-century selective harvesting halved the density of large trees, with some variation among forest types. In contrast, the density of small trees doubled or tripled early in the 20th century, probably due to land-use change and a relatively cool, wet climate. Contrary to the common perception that dry ponderosa pine forests are the most highly departed from historical conditions, we found a greater departure in the modern composition of small trees in warm–moist environments than in either hot–dry or cold–wet environments. Furthermore

  2. 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

  3. 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

  4. Sun and Shade leaves, SIF, and Photosynthetic Capacity

    Science.gov (United States)

    Berry, J. A.; Badgley, G.

    2016-12-01

    Recent advances in retrieval of solar induced chlorophyll fluorescence (SIF) have opened up new possibilities for remote sensing of canopy physiology and structure. To date most of the emphasis has been placed on SIF as an indicator of stress and photosynthetic capacity. However, it is clear that canopy structure can also have an influence. To this point, simulations of SIF in land surface models tend to under predict observed variation in SIF. Also, large, systematic differences in SIF from different canopy types seem to correlate well with the photosynthetic capacity of these canopies. SIF emissions from pampered crops can be several-fold that from evergreen, needle-leaf forests. Yet, these may have similar vegetation indices and absorb a similar fraction of incident PAR. SIF photons produced in a conifer canopy do have a lower probability of escaping its dense, clumped foliage. However, this does not explain the correlated differences in photosynthetic rate and SIF. It is useful, in this regard, to consider the separate contributions of sun and shade leaves to the SIF emitted by a canopy. Sun leaves tend to be displayed to intercept the direct solar beam, and these highly illuminated leaves are often visible from above the canopy. Sun leaves produce more SIF and a large fraction of it escapes. Therefore, the intensity of SIF may be a sensitive indicator of the partitioning of absorbed PAR to sun and shade leaves. Many models account tor the different photosynthetic capacity of sun and shade leaves in calculating canopy responses. However, the fraction of leaves in each category is usually parameterized by an assumed leaf angle distribution (e.g. spherical). In reality, the sun/shade fraction can vary over a wide range, and it has been difficult to measure. SIF and possibly near-IR reflectance of canopies can be used to specify this key parameter with obvious importance to understanding photosynthetic rate.

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

    African Journals Online (AJOL)

    To delay the harvest of Sultani Cekirdeksiz grape variety and to reduce pre and post-harvest botrytis bunch rot severity, shading and covering material application were tested in 2009 to 2010 growing periods. In this study, grape vines were shaded with shading materials which had three different shading densities (35, 55, ...

  6. 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...

  7. 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...

  8. 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)

  9. 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...

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

    Science.gov (United States)

    Holmgren, Milena; Gómez-Aparicio, Lorena; Quero, José Luis; Valladares, Fernando

    2012-06-01

    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 models about the role of shade under dry conditions: the trade-off and the facilitation hypotheses. We performed a meta-analysis of field and greenhouse studies evaluating the effects of drought at two or more irradiance levels on nine response variables describing plant physiological condition, growth, and survival. We explored differences in plant response across plant functional types, ecosystem types and methodological approaches. The data were best fit using quadratic models indicating a humped-back shape response to drought along an irradiance gradient for survival, whole plant biomass, maximum photosynthetic capacity, stomatal conductance and maximal photochemical efficiency. Drought effects were ameliorated at intermediate irradiance, becoming more severe at higher or lower light levels. This general pattern was maintained when controlling for potential variations in the strength of the drought treatment among light levels. Our quantitative meta-analysis indicates that dense shade ameliorates drought especially among drought-intolerant and shade-tolerant species. Wet tropical species showed larger negative effects of drought with increasing irradiance than semiarid and cold temperate species. Non-linear responses to irradiance were stronger under field conditions than under controlled greenhouse conditions. Non-linear responses to drought along the irradiance gradient reconciliate opposing views in plant ecology, indicating that facilitation is more likely within certain range of environmental conditions, fading under deep shade, especially for drought-tolerant species.

  11. Shade variance in ceramic restoration and shade tab: An in vitro study

    Directory of Open Access Journals (Sweden)

    Pannaikadu Somasundaram Prabu

    2012-01-01

    Full Text Available Background: In clinical practice aesthetics for any restoration needs to consider the parameters of surface form, translucency and colour.To achieve ideal aesthetics the colour replication process for dental porcelain is the most important step which comprises of a shade selection phase followed by shade duplication. Materials and Methods: The ceramic brands Vita VMK95 (classic and Ivoclar classic V were used for comparison with Vita classic shade tab guide shades A2 and B2. The samples were made of specific shape, size, and were of the recommended dimensions from investing self-cure acrylic strips to casted NiCr specimens Objective. The objective of this study was to quantify the results in CIE AE units system for the colour differences between the Vita shade guide colours and two commercial porcelains for metal ceramic crowns. Results: The results indicated that the porcelains do not match the shade guides to which they are compared and shade variations exist between different lots of porcelain from the same and different manufacturer. Conclusion: Problems identified that porcelains do not match the shade guides to which they are compared and shade variations exist between different lots of porcelain from the same and different manufacturer

  12. Determination of industrial color tolerance limits: case studies in the textile industry

    Science.gov (United States)

    Gay, Jennifer; Hirschler, Robert

    2002-06-01

    The approach and findings during the application of instrumental color quality control in industry are described, where the best tolerance formulae and tolerance limits were determined by correlating visual and instrumental evaluations. A panel of previously tested observers evaluated a collection of samples taken from production and color measurements are then compared to these assessments, according to different color difference formulae. T he formula and the limit giving the best agreement with visual evaluations were determined with two different methods. For a large variety of textile substrates, processes and market situations the CMC(2:1) formula was always the best or one of the bests, but the limits varied widely, according to the individual application. Additional shade sorting, based on the tolerance limit, was also applied in several companies. The ideal box size was also determined by comparing visual and instrumental evaluations. The application as logistical tools was established according to individual necessities.

  13. Shade Trees Spatial Distribution and Its Effect on Grains and Beverage Quality of Shaded Coffee Trees

    Directory of Open Access Journals (Sweden)

    Francisco José da Silva Neto

    2018-01-01

    Full Text Available Shading coffee trees has gained importance, especially among smallholders, as an option to improve the products’ quality, therefore acquiring place at the specialty coffee market, where consumers are willing to give bonus for quality. This work aims to evaluate the influence of shade trees’ spatial distribution among coffee trees’ agronomic characteristics, yield, and beans and cup quality of shaded coffee trees. The experimental design consisted of completely randomized blocks with six repetitions and four treatments: coffee trees on shade trees planting rows, distant one meter from the trunk; coffee trees on shade trees planting row, distant six meters from the trunk; and coffee plants between the rows of shade trees, parallel to the previous treatments. The parameters analyzed were plant height, canopy diameter, plagiotropic branches’ length, yield, coffee fruits’ phenological stage, ripe cherries’ Brix degree, percentage of black, unripe, and insect damaged beans, bean size, and beverage quality. Shade trees quickened coffee fruits’ phenological stage of coffee trees nearest to them. This point also showed the best beverage quality, except for overripe fruits. The remaining parameters evaluated were not affected by shade trees’ spatial distribution.

  14. Ranking of persister genes in the same Escherichia coli genetic background demonstrates varying importance of individual persister genes in tolerance to different antibiotics

    Directory of Open Access Journals (Sweden)

    Nan eWu

    2015-09-01

    Full Text Available Despite the identification of many genes and pathways involved in the persistence phenomenon of bacteria, the relative importance of these genes in a single organism remains unclear. Here, using Escherichia coli as a model, we generated mutants of 21 known candidate persister genes and compared the relative importance of these mutants in persistence to various antibiotics (ampicillin, gentamicin, norfloxacin, and trimethoprim at different times. We found that oxyR, dnaK, sucB, relA, rpoS, clpB, mqsR, and recA were prominent persister genes involved in persistence to multiple antibiotics. These genes map to the following pathways: antioxidative defense pathway (oxyR, global regulators (dnaK, clpB, and rpoS, energy production (sucB, stringent response (relA, toxin–antitoxin (TA module (mqsR, and SOS response (recA. Among the TA modules, the ranking order was mqsR, lon, relE, tisAB, hipA, and dinJ. Intriguingly, rpoS deletion caused a defect in persistence to gentamicin but increased persistence to ampicillin and norfloxacin. Mutants demonstrated dramatic differences in persistence to different antibiotics at different time points: some mutants (oxyR, dnaK, phoU, lon, recA, mqsR, and tisAB displayed defect in persistence from early time points, while other mutants (relE, smpB, glpD, umuD, and tnaA showed defect only at later time points. These results indicate that varying hierarchy and importance of persister genes exist and that persister genes can be divided into those involved in shallow persistence and those involved in deep persistence. Our findings suggest that the persistence phenomenon is a dynamic process with different persister genes playing roles of variable significance at different times. These findings have implications for improved understanding of persistence phenomenon and developing new drugs targeting persisters for more effective cure of persistent infections.

  15. The combined influence of binocular disparity and shading on pictorial shape

    NARCIS (Netherlands)

    Doorschot, P. C A; Kappers, A. M L; Koenderink, Jan J.

    The combined influence of binocular disparity and shading on pictorial shape was studied. Stimuli were several pairs of stereo photographs of real objects. The stereo base was 0, 7, or 14 cm, and the location of the light source was varied over three positions (one from about the viewpoint of the

  16. Shade guide optimization--a novel shade arrangement principle for both ceramic and composite shade guides when identifying composite test objects.

    Science.gov (United States)

    Østervemb, Niels; Jørgensen, Jette Nedergaard; Hørsted-Bindslev, Preben

    2011-02-01

    The most widely used shade guide for composite materials is made of ceramic and arranged according to a non-proven method. There is a need for a composite shade guide using a scientifically based arrangement principle. To compare the shade tab arrangement of the Vitapan Classical shade guide and an individually made composite shade guide using both the originally proposed arrangement principle and arranged according to ΔE2000 values with hue group division. An individual composite shade guide made from Filtek Supreme XT body colors was compared to the Vitapan Classical shade guide. Twenty-five students matched color samples made from Filtek Supreme XT body colors using the two shade guides arranged after the two proposed principles--four shade guides in total. Age, sequence, gender, time, and number of correct matches were recorded. The proposed visually optimal composite shade guide was both fastest and had the highest number of correct matches. Gender was significantly associated with time used for color sampling but not regarding the number of correct shade matches. A composite shade guide is superior compared to the ceramic Vitapan Classical guide when using composite test objects. A rearrangement of the shade guide according to hue, subdivided according to ΔE2000, significantly reduces the time needed to take a color sample and increases the number of correct shade matches. Total color difference in relation to the lightest tab with hue group division is recommended as a possible and universally applicable mode of tab arrangement in dental color standards. Moreover, a shade guide made of the composite materials itself is to be preferred as both a faster and more accurate method of determining color. © 2011, COPYRIGHT THE AUTHORS. JOURNAL COMPILATION © 2011, WILEY PERIODICALS, INC.

  17. Tanning Shade Gradations of Models in Mainstream Fitness and Muscle Enthusiast Magazines: Implications for Skin Cancer Prevention in Men.

    Science.gov (United States)

    Basch, Corey H; Hillyer, Grace Clarke; Ethan, Danna; Berdnik, Alyssa; Basch, Charles E

    2015-07-01

    Tanned skin has been associated with perceptions of fitness and social desirability. Portrayal of models in magazines may reflect and perpetuate these perceptions. Limited research has investigated tanning shade gradations of models in men's versus women's fitness and muscle enthusiast magazines. Such findings are relevant in light of increased incidence and prevalence of melanoma in the United States. This study evaluated and compared tanning shade gradations of adult Caucasian male and female model images in mainstream fitness and muscle enthusiast magazines. Sixty-nine U.S. magazine issues (spring and summer, 2013) were utilized. Two independent reviewers rated tanning shade gradations of adult Caucasian male and female model images on magazines' covers, advertisements, and feature articles. Shade gradations were assessed using stock photographs of Caucasian models with varying levels of tanned skin on an 8-shade scale. A total of 4,683 images were evaluated. Darkest tanning shades were found among males in muscle enthusiast magazines and lightest among females in women's mainstream fitness magazines. By gender, male model images were 54% more likely to portray a darker tanning shade. In this study, images in men's (vs. women's) fitness and muscle enthusiast magazines portrayed Caucasian models with darker skin shades. Despite these magazines' fitness-related messages, pro-tanning images may promote attitudes and behaviors associated with higher skin cancer risk. To date, this is the first study to explore tanning shades in men's magazines of these genres. Further research is necessary to identify effects of exposure to these images among male readers. © The Author(s) 2014.

  18. Minimisation of Power loss from partially shaded solar cell arrays

    Energy Technology Data Exchange (ETDEWEB)

    Maine, Tony; Bell, John [Queensland University of Technology, Brisbane (Australia). Built Environment Engineering; Martin, Stewart [University of South Australia, Mawson Lakes Campus, SA (Australia). School of Electrical and Information Engineering

    2008-07-01

    In conventional wiring schemes the output from a partially shaded solar cell array drops rapidly to that of the fully shaded array even when only a small fraction is shaded. In this paper circuit simulation has been used to show that by dynamically reconfiguring the array, the power losses due to shading can be significantly reduced. Reconfiguration is achieved by using switching microcircuits with on-chip photo detectors to determine which parts of the array are in shade. The currents from the shaded and unshaded sections of the array are separated and then connected in parallel to a maximum power point tracker. It is shown that by using this reconfiguration that the power output from a partially shaded array can be increased by at least 100% compared with that from a conventional series connected array over a range of shading conditions. (orig.)

  19. 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...

  20. 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...

  1. 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....

  2. Plants' responses to drought and shade environments

    African Journals Online (AJOL)

    전병기

    Among them, drought is widely known as the main factor that limits plants' growth, productivity and development (Reddy et al., 2004; Shao et al., 2008; Li et al., 2009). Recently, drought occured frequently all over the globe due to climate changes (Khaine and Woo, 2015). Light and shade are very important environements ...

  3. 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

  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. 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

  7. Initial Development of Four Forest Species in Different Shading Conditions

    Directory of Open Access Journals (Sweden)

    C. C. Silva

    2013-07-01

    Full Text Available Abstract: Evaluated the initial development through destructive and non-destructive sampling, forest species Adenanthera pavonina, Cassia fistula, Parkia pendula and Hymenolobium petraeum, propagated by seeds at different levels of shading screens black poliefinas (0, 50 and 65% , in the region of Sinop, MT. There were no significant interactions between time and level of shading to any variable. Changes in fresh and dry weight at all levels of shading occurred from 30 DAT. The highest rates of growth were observed in 50% shading to A. pavonina, P. pendula and H. petraeum and 65% shading for C. fistula.Keywords: seedling, growth, physiology, climatic conditions.

  8. Photosynthetic response of Eriophorum vaginatum to in situ shrub shading in tussock tundra of northern Alaska

    Science.gov (United States)

    Anderson-Smith, A.; Pattison, R.; Sullivan, P.; Welker, J. M.

    2009-12-01

    Eriophorum vaginatum (Cotton Grass) is an important component of moist acidic tussock tundra, a plant community that appears to be undergoing changes in species composition associated with climate warming. This species is one of the most abundant in the arctic tundra, and provides important forage for caribou in their calving grounds on the Arctic Coastal Plain and along their migratory route through the foothills of Alaska. Recently, remote sensing data, repeat photography and plot-level measurements have indicated that shrub abundance is increasing while Eriophorum abundance is either constant or decreasing. One possible explanation for the reduction of Eriophorum while Betula nana is increasing, is that lower light levels in the taller Betula canopy may be constraining Eriophorum photosynthesis and subsequently reducing plant growth. This study measured the effect of shading on the light response of Eriphorum leaf photosynthesis in four different sites near Toolik Lake Alaska during the summer of 2009. Measurements were taken in: 1) a shrub patch within the drift zone of the ITEX long term snow fence experiment, 2) an LTER shade house (50% shading) built in 1989, 3) water track site 1 and water track site 2 (i.e. control areas with no experimental manipulations) Average photosynthetic rates for Eriophorum at a light level of 800 PAR varied from 3.8 to 10.9 umol m-2 s-1 and were not significantly different in shaded and unshaded areas. This study indicates that shading by shrubs does not appear to be altering the light response of Eriophorum nor does long-term shading by itself eliminate Eriophorum from the community. An alternative explanation for the decline of Eriophorum while Betula increases in abundance under changing climates may be related to plant and soil mineral nutrition, plant water relations or biotic processes involving herbivores.

  9. 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 (Pceramic systems designed for porcelain veneers 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.

  10. 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.

  11. Consistency in color parameters of a commonly used shade guide.

    Science.gov (United States)

    Tashkandi, Esam

    2010-01-01

    The use of shade guides to assess the color of natural teeth subjectively remains one of the most common means for dental shade assessment. Any variation in the color parameters of the different shade guides may lead to significant clinical implications. Particularly, since the communication between the clinic and the dental laboratory is based on using the shade guide designation. The purpose of this study was to investigate the consistency of the L∗a∗b∗ color parameters of a sample of a commonly used shade guide. The color parameters of a total of 100 VITAPAN Classical Vacuum shade guide (VITA Zahnfabrik, Bad Säckingen, Germany(were measured using a X-Rite ColorEye 7000A Spectrophotometer (Grand Rapids, Michigan, USA). Each shade guide consists of 16 tabs with different designations. Each shade tab was measured five times and the average values were calculated. The ΔE between the average L∗a∗b∗ value for each shade tab and the average of the 100 shade tabs of the same designation was calculated. Using the Student t-test analysis, no significant differences were found among the measured sample. There is a high consistency level in terms of color parameters of the measured VITAPAN Classical Vacuum shade guide sample tested.

  12. Digital Shaded-Relief Image of Alaska

    Science.gov (United States)

    Riehle, J.R.; Fleming, Michael D.; Molnia, B.F.; Dover, J.H.; Kelley, J.S.; Miller, M.L.; Nokleberg, W.J.; Plafker, George; Till, A.B.

    1997-01-01

    Introduction One of the most spectacular physiographic images of the conterminous United States, and the first to have been produced digitally, is that by Thelin and Pike (USGS I-2206, 1991). The image is remarkable for its crispness of detail and for the natural appearance of the artificial land surface. Our goal has been to produce a shaded-relief image of Alaska that has the same look and feel as the Thelin and Pike image. The Alaskan image could have been produced at the same scale as its lower 48 counterpart (1:3,500,000). But by insetting the Aleutian Islands into the Gulf of Alaska, we were able to print the Alaska map at a larger scale (1:2,500,000) and about the same physical size as the Thelin and Pike image. Benefits of the 1:2,500,000 scale are (1) greater resolution of topographic features and (2) ease of reference to the U.S. Geological Survey (USGS) (1987) Alaska Map E and the statewide geologic map (Beikman, 1980), which are both 1:2,500,000 scale. Manually drawn, shaded-relief images of Alaska's land surface have long been available (for example, Department of the Interior, 1909; Raisz, 1948). The topography depicted on these early maps is mainly schematic. Maps showing topographic contours were first available for the entire State in 1953 (USGS, 1:250,000) (J.H. Wittmann, USGS, written commun., 1996). The Alaska Map E was initially released in 1954 in both planimetric (revised in 1973 and 1987) and shaded-relief versions (revised in 1973, 1987, and 1996); topography depicted on the shaded-relief version is based on the 1:250,000-scale USGS topographic maps. Alaska Map E was later modified to include hypsometric tinting by Raven Maps and Images (1989, revised 1993) as copyrighted versions. Other shaded-relief images were produced for The National Geographic Magazine (LaGorce, 1956; 1:3,000,000) or drawn by Harrison (1970; 1:7,500,000) for The National Atlas of the United States. Recently, the State of Alaska digitally produced a shaded-relief image

  13. ATOMLLL: atoms with shading and highlights

    International Nuclear Information System (INIS)

    Max, N.L.; y.

    1979-01-01

    The ATOMS program, written at Bell Telephone Laboratory, is capable of determining the visible portions of a scene consisting of interpenetrating spheres and cylinders, put together to represent space-filling or ball-and-stick molecular models. The Lawrence Livermore Laboratory version contains enhancements to add shading and highlights, and to render the spheres on film as ellipses, so they will appear round when projected in various wide-screen formats. The visible parts of each sphere or cylinder are shaded by a minicomputer controlling the film recorder, thus releasing the main computer from transferring the millions of intensity values for each frame. The minicomputer is microprogrammed with an efficient algorithm for the intensities, which uses the color look-up tables in the film recorder to store the reflectance as a function of angle of incidence. 8 references

  14. Composite shade guides and color matching.

    Science.gov (United States)

    Paolone, Gaetano; Orsini, Giovanna; Manauta, Jordi; Devoto, Walter; Putignano, Angelo

    2014-01-01

    Finding reliable systems that can help the clinician match the color of direct composite restorations is often an issue. After reviewing several composite shade guides available on the market and outlining their main characteristics and limits (unrealistic specimen thickness, not made with the same material the clinician will use, only a few allow to overlap enamel tabs on dentin ones), the authors evaluated the reliability of a system designed to produce self-made standardized "tooth-shaped" shade guide specimens. Small changes in composite enamel thickness may determine huge differences in esthetic outcomes. In conclusion, the results showed that all the specimens demonstrated comparable enamel thickness in all the examined areas (cervical, middle, incisal).

  15. Combined surface and volumetric occlusion shading

    KAUST Repository

    Schott, Matthias O.; Martin, Tobias; Grosset, A. V Pascal; Brownlee, Carson; Hollt, Thomas; Brown, Benjamin P.; Smith, Sean T.; Hansen, Charles D.

    2012-01-01

    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.

  16. 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.

  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. Leaf Physiological and Morphological Responses to Shade in Grass-Stage Seedlings and Young Trees of Longleaf Pine

    Directory of Open Access Journals (Sweden)

    Lisa J. Samuelson

    2012-08-01

    Full Text Available Longleaf pine has been classified as very shade intolerant but leaf physiological plasticity to light is not well understood, especially given longleaf pine’s persistent seedling grass stage. We examined leaf morphological and physiological responses to light in one-year-old grass-stage seedlings and young trees ranging in height from 4.6 m to 6.3 m to test the hypothesis that young longleaf pine would demonstrate leaf phenotypic plasticity to light environment. Seedlings were grown in a greenhouse under ambient levels of photosynthetically active radiation (PAR or a 50% reduction in ambient PAR and whole branches of trees were shaded to provide a 50% reduction in ambient PAR. In seedlings, shading reduced leaf mass per unit area (LMA, the light compensation point, and leaf dark respiration (RD, and increased the ratio of light-saturated photosynthesis to RD and chlorophyll b and total chlorophyll expressed per unit leaf dry weight. In trees, shading reduced LMA, increased chlorophyll a, chlorophyll b and total chlorophyll on a leaf dry weight basis, and increased allocation of total foliar nitrogen to chlorophyll nitrogen. Changes in leaf morphological and physiological traits indicate a degree of shade tolerance that may have implications for even and uneven-aged management of longleaf pine.

  19. 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.

  20. Relationship between natural tooth shade and skin colour.

    Science.gov (United States)

    Nourbakhsh, M; Mousavinejad, N; Adli, A R; Harati, M

    2013-06-01

    The purpose of this study was to assess the correlation of skin colour and tooth shade. One hundred and twenty six individuals aging between 18 to 25 years participated in this study. Colour of the maxillary central incisors was examined by VITA easy shade. Tooth shades were assigned to four ordinal values. Nivea Beauty Protect Foundation shade sample was used as a guide to assess facial skin colour Shin colours were also assigned to four ordinal values. Spearman test revealed that there was a significant relationship between tooth shade and skin colour Total co-relation factor was 51.6% (p men (p <0 .01). The highest tooth shade prevalence belonged to the second group and the highest skin colour prevalence was also in the second skin colour group.

  1. Shade selection performed by novice dental professionals and colorimeter.

    Science.gov (United States)

    Klemetti, E; Matela, A-M; Haag, P; Kononen, M

    2006-01-01

    The objective of this study was to test inter-observer variability in shade selection for porcelain restorations, using three different shade guides: Vita Lumin Vacuum, Vita 3D-Master and Procera. Nineteen young dental professionals acted as observers. The results were also compared with those of a digital colorimeter (Shade Eye Ex; Shofu, Japan). Regarding repeatability, no significant differences were found between the three shade guides, although repeatability was relatively low (33-43%). Agreement with the colorimetric results was also low (8-34%). In conclusion, shade selection shows moderate to great inter-observer variation. In teaching and standardizing the shade selection procedure, a digital colorimeter may be a useful educational tool.

  2. Impact of Manually Controlled Solar Shades on Indoor Visual Comfort

    Directory of Open Access Journals (Sweden)

    Jian Yao

    2016-07-01

    Full Text Available Daylight plays a significant role in sustainable building design. The purpose of this paper was to investigate the impact of manual solar shades on indoor visual comfort. A developed stochastic model for manual solar shades was modeled in Building Controls Virtual Test Bed, which was coupled with EnergyPlus for co-simulation. Movable solar shades were compared with two unshaded windows. Results show that movable solar shades have more than half of the working hours with a comfortable illuminance level, which is about twice higher than low-e windows, with a less significant daylight illuminance fluctuation. For glare protection, movable solar shades increase comfortable visual conditions by about 20% compared to low-e windows. Moreover, the intolerable glare perception could be reduced by more than 20% for movable solar shades.

  3. Mts. Agung and Batur, Bali, Shaded Relief and Colored Height

    Science.gov (United States)

    2004-01-01

    Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.Location: 8.33 degrees South latitude, 115.17 degrees East longitude Orientation: Looking southwest Size: scale varies in this perspective image Image Data: shaded and colored SRTM elevation model Date Acquired: February 2000

  4. Differences in Proteins Synthesized in Needles of Unshaded and Shaded Pinus ponderosa var Scopulorum Seedlings during Prolonged Drought 1

    Science.gov (United States)

    Vance, Nan C.; Copes, Donald O.; Zaerr, Joe B.

    1990-01-01

    Proteins were radiolabeled and extracted from needles of Pinus ponderosa var scopulorum (Dougl. ex Laws.) seedlings progressively drought-stressed for about 1 month. A set of novel, low molecular weight proteins was detected in fluorographs of two-dimensional gels when relative water content of needles fell below 70%. Their synthesis was undetectable in the fully recovered seedlings within 48 hours after rewatering. In similarly stressed seedlings that were shaded to 10% full light, the low molecular weight polypeptides were not detected or appeared at very low levels. The shaded seedlings, in which drought tolerance was reduced, did not recover upon termination of the drought. The results suggest that protein synthesis induced by water deficit in drought-tolerant seedlings may contribute to resisting the effects of cellular dehydration. Images Figure 1 Figure 2 PMID:16667397

  5. STUDIES OF SHADING LEVELS AND NUTRITION SOURCES ON GROWTH, YIELD

    Directory of Open Access Journals (Sweden)

    Edi Purwanto

    2011-10-01

    Full Text Available Growth and biochemical content of medicinal crops are influenced by agroecosystems characteristics . The objective of this research was to determine the optimum shading level and type of fertilizer as sources of nutrition on the growth, yield, and andrographolide content of sambiloto. The experiment used Split Plot Design with basic design of Randomized Complete Block Design arranged with two treatment factors, with three replications. The first factor as the main plot was shading levels, namely without shading, 25% shading, 50% shading, and 75% shading. The second factor as the sub plot was sources of nutrition reprented by type of fertilizer, namely NPK fertilizer, cow stable fertilizer, and compost fertilizer. The result of research indicated that shading level and the kind of nutrition influenced some growth and yield variables such as number of leaves, number of branches, plant height, plant dry weight and simplisia weight, and andrographolide content. Interaction of shading level at 25% and straw compost fertilizer performed best in growth characteristics, while the highest andrographolide content resulted from the treatment combination of 50% shading level and straw compost fertilizer.

  6. 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.

  7. 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

  8. Bali, Shaded Relief and Colored Height

    Science.gov (United States)

    2004-01-01

    The volcanic nature of the island of Bali is evident in this shaded relief image generated with data from the Shuttle Radar Topography Mission (SRTM).Bali, along with several smaller islands, make up one of the 27 Provinces of Indonesia. It lies over a major subduction zone where the Indo-Australian tectonic plate collides with the Sunda plate, creating one of the most volcanically active regions on the planet.The most significant feature on Bali is Gunung Agung, the symmetric, conical mountain at the right-center of the image. This 'stratovolcano,' 3,148 meters (10,308 feet) high, is held sacred in Balinese culture, and last erupted in 1963 after being dormant and thought inactive for 120 years. This violent event resulted in over 1,000 deaths, and coincided with a purification ceremony called Eka Dasa Rudra, meant to restore the balance between nature and man. This most important Balinese rite is held only once per century, and the almost exact correspondence between the beginning of the ceremony and the eruption is though to have great religious significance.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

  9. Colored Height and Shaded Relief, Kamchatka Peninsula

    Science.gov (United States)

    2002-01-01

    Russia's Kamchatka Peninsula, lying between the Sea of Okhotsk to the west and the Bering Sea and Pacific Ocean to the east, is one of the most active volcanic regions along the Pacific Ring of Fire. It covers an area about the size of Colorado but contains more than 100 volcanoes stretching across the 1000-kilometer-long (620-mile-long) land mass. A dozen or more of these have active vents, with the youngest located along the eastern half of the peninsula. This color-coded shaded relief image, generated with data from the Shuttle Radar Topography Mission (SRTM), shows Kamchatka's volcanic nature to dramatic effect.Kliuchevskoi, one of the most active and renowned volcanoes in the world, dominates the main cluster of volcanoes called the Kliuchi group, visible as a circular feature in the center-right of the image. The two other main volcanic ranges lie along northeast-southwest lines, with the older, less active range occupying the center and western half of Kamchatka. The younger, more active belt begins at the southernmost point of the peninsula and continues upward along the Pacific coastline.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction, so northern slopes appear bright and southern slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and brown to white at the highest elevations.The Shuttle Radar Topography Mission flew aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (200

  10. 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

  11. 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.

  12. Development and bloom in hybrids of wild passion fruit cultivated in different types of pots and shading levels

    Directory of Open Access Journals (Sweden)

    Eileen Azevedo Santos

    2012-04-01

    Full Text Available Ornamental hybrids of passion flowers are thoroughly diffused in many countries and used in the decoration of houses and gardens. However, the cultivation of ornamental passion fruits practically unexploited in Brazil. This study aimed at evaluating the growth and blooming of F1 hybrids of Passiflora L. (P. sublanceolata J.M. MacDougal [ex P. palmeri var. sublanceolata Killip] vs. P. foetida var. foetida L. cultivated in ceramic and concrete pots under different shading levels. The vegetative and flower evaluations were carried out weekly, in clonal cuttings 60 days after rooting. The height, leaf length and width, the number of internodes and leaves and stem diameter were evaluated using a randomized complete design in a factorial scheme which corresponded to two genotypes, two types of pot, three shading levels (25 %, 50 %, 75 % and seven weeks of evaluation, with four replications. For the variable number of flowers, the same experimental design was adopted. However, the number of evaluations was modified for three periods, but this was not considered for the flower diameter and leaf area. The shading levels of 25 % and 50 % were the most favorable to the growth in height, whereas hybrid genotypes under 25 % shade had greater increase in the number of leaves, internodes and stem diameter, showing tolerance to moderate shade. The higher values for length, width and leaf area were observed at 75 % shade. The greatest number of flowers was verified at 25 % shadow in concrete pots. As for the types of pot, the ceramic ones were more favorable to the growth of hybrid plants during the first weeks of acclimatization to the treatments, and the concrete ones were more propitious to blooming. Thus, the use of hybrid plants in concrete pots for the ornamentation of internal environments is recommended, if they are well illuminated.

  13. Shaded Relief with Height as Color, Yucatan Peninsula, Mexico

    Science.gov (United States)

    2003-01-01

    This shaded relief image of Mexico's Yucatan Peninsula show a subtle, but unmistakable, indication of the Chicxulub impact crater. Most scientists now agree that this impact was the cause of the Cretatious-Tertiary Extinction, the event 65 million years ago that marked the sudden extinction of the dinosaurs as well as the majority of life then on Earth.Most of the peninsula is visible here, along with the island of Cozumel off the east coast. The Yucatan is a plateau composed mostly of limestone and is an area of very low relief with elevations varying by less than a few hundred meters (about 500 feet.) In this computer-enhanced image the topography has been greatly exaggerated to highlight a semicircular trough, the darker green arcing line at the upper left corner of the peninsula. This trough is only about 3 to 5 meters (10 to 15 feet) deep and is about 5 km. wide (3 miles), so subtle that if you walked across it you probably would not notice it, and is a surface expression of the crater's outer boundary. Scientists believe the impact, which was centered just off the coast in the Caribbean, altered the subsurface rocks such that the overlying limestone sediments, which formed later and erode very easily, would preferentially erode on the vicinity of the crater rim. This formed the trough as well as numerous sinkholes (called cenotes) which are visible as small circular depressions.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 northwestern slopes appear bright and southeastern 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.For a smaller, annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site] (Large image: 1.5 m

  14. Solar Shading System Based on Daylight Directing Glass Lamellas

    DEFF Research Database (Denmark)

    Laustsen, Jacob Birck; Santos, Inês; 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...

  15. 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 ...

  16. Influence of shading on container-grown flowering dogwoods

    Science.gov (United States)

    Bare root dogwoods can be successfully grown when transplanted into a container production system. Shade treatments regardless of color or density did have an effect on the plant growth of Cherokee Brave™ and Cherokee Princess dogwood. Plants grown under 50% black and 50% white shade had more heigh...

  17. Tolerância à interferência de plantas competidoras e habilidade de supressão por genótipos de soja: II. Resposta de variáveis de produtividade Tolerance to interference of competing plants and suppressive ability by soybean genotypes: II. Response of yield variables

    Directory of Open Access Journals (Sweden)

    F.P. Lamego

    2004-12-01

    Full Text Available As perdas de produtividade das culturas em decorrência da competição de plantas concorrentes geralmente aumentam quanto mais semelhantes forem suas características morfofisiológicas. O objetivo deste trabalho foi avaliar os efeitos da competição de cultivares de soja, simulando espécies daninhas dicotiledôneas, sobre cultivares de soja portadores de características diferenciais de planta. Para isso, conduziu-se um experimento em campo, em Eldorado do Sul-RS. Os fatores e tratamentos comparados foram: três condições de competição (ausência de plantas de soja concorrentes e presença de plantas concorrentes do cultivar de soja BRS 205 ou Cobb; e quatro cultivares reagentes de soja à competição (IAS 5, BR-16, CD 205 e Fepagro RS-10. Avaliaram-se variáveis relacionadas à produtividade dos cultivares e outras correlatas. Características dissimilares em plantas de cultivares de soja, como estatura e ciclo, resultaram em habilidade competitiva diferenciada com plantas concorrentes. O cultivar de soja CD 205, de estatura elevada e ciclo tardio, mostrou alta habilidade competitiva; IAS 5, de baixa estatura e ciclo precoce, apresentou baixa tolerância à competição, enquanto BR-16 e Fepagro RS-10 são intermediários. Cultivares com elevada habilidade competitiva, além de tolerarem a competição, preservando o potencial de produtividade, também suprimem a produção de grãos das plantas concorrentes.Due to concurrent plant competition, crop yield losses generally increase as their morphophysiological characteristics become more similar. The objective of this research was to evaluate the competitive effects of soybean cultivars mimicking dicotyledonous weed species on soybean cultivars holding dissimilar plant characteristics. Thus, a field experiment was carried out in Eldorado do Sul-RS. The factors and treatments compared were: three competition conditions (absence of competing plants and presence of the soybean cultivar

  18. Influences of shading and fertilization on on-farm yields of cocoa in Ghana

    DEFF Research Database (Denmark)

    Richard, Asare; Asare, Rebecca Ashley; Asante, Winston Adams

    2017-01-01

    Most cocoa farms in Ghana are cultivated in complex agroforest systems, with plant growth and cocoa productivity being affected. The objective of this study was to investigate how shade trees affect cocoa yield, temperature and soil nutrients in low-input cocoa systems. Establishing plots on 24...... farms in four locations (districts) in Ghana, we assessed the influence of varying canopy cover and fertilization on cocoa yields. Results showed no relationship between canopy cover and cocoa yields in the light crop season (February to August). For the main crop season (September to January...... recorded in the cocoa canopies were above the recommended range for this species. Although shade trees had a slight modifying effect on peak temperatures, the magnitude appeared too small to have any practical effects....

  19. "Magnetic" termite mound surfaces are oriented to suit wind and shade conditions.

    Science.gov (United States)

    Jacklyn, Peter M

    1992-09-01

    The termites Amitermes meridionalis and A. laurensis construct remarkable meridional or "magnetic" mounds in northern Australia. These mounds vary geographically in mean orientation in a manner that suggests such variation is an adaptive response to local environmental conditions. Theoretical modelling of solar irradiance and mound rotation experiments show that maintenance of an eastern face temperature plateau during the dry season is the most likely physical basis for the mound orientation response. Subsequent heat transfer analysis shows that habitat wind speed and shading conditions also affect face temperature gradients such as the rate of eastern face temperature change. It is then demonstrated that the geographic variation in mean mound orientation follows the geographic variation in long-term wind speed and shading conditions across northern Australia such that an eastern face temperature plateau is maintained in all locations.

  20. Shaded Relief of Rio Sao Francisco, Brazil

    Science.gov (United States)

    2000-01-01

    This topographic image acquired by SRTM shows an area south of the Sao Francisco River in Brazil. The scrub forest terrain shows relief of about 400 meters (1300 feet). Areas such as these are difficult to map by traditional methods because of frequent cloud cover and local inaccessibility. This region has little topographic relief, but even subtle changes in topography have far-reaching effects on regional ecosystems. The image covers an area of 57 km x 79 km and represents one quarter of the 225 km SRTM swath. Colors range from dark blue at water level to white and brown at hill tops. The terrain features that are clearly visible in this image include tributaries of the Sao Francisco, the dark-blue branch-like features visible from top right to bottom left, and on the left edge of the image, and hills rising up from the valley floor. The San Francisco River is a major source of water for irrigation and hydroelectric power. Mapping such regions will allow scientists to better understand the relationships between flooding cycles, forestation and human influences on ecosystems.This shaded relief image was generated using topographic data from the Shuttle Radar Topography Mission. A computer-generated artificial light source illuminates the elevation data to produce a pattern of light and shadows. Slopes facing the light appear bright, while those facing away are shaded. On flatter surfaces, the pattern of light and shadows can reveal subtle features in the terrain. Shaded relief maps are commonly used in applications such as geologic mapping and land use planning.The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, uses 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. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200

  1. Shaded relief of Bahia State, Brazil

    Science.gov (United States)

    2000-01-01

    This topographic image is the first to show the full 240-kilometer-wide (150 mile)swath collected by the Shuttle Radar Topography Mission (SRTM). The area shown is in the state of Bahia in Brazil. The semi-circular mountains along the left side of the image are the Serra Da Jacobin, which rise to 1100 meters (3600 feet) above sea level. The total relief shown is approximately 800 meters (2600 feet). The top part of the image is the Sertao, a semi-arid region, that is subject to severe droughts during El Nino events. A small portion of the San Francisco River, the longest river (1609 kilometers or 1000 miles) entirely within Brazil, cuts across the upper right corner of the image. This river is a major source of water for irrigation and hydroelectric power. Mapping such regions will allow scientists to better understand the relationships between flooding cycles, drought and human influences on ecosystems.This shaded relief image was generated using topographic data from the Shuttle Radar Topography Mission. A computer-generated artificial light source illuminates the elevation data to produce a pattern of light and shadows. Slopes facing the light appear bright, while those facing away are shaded. On flatter surfaces, the pattern of light and shadows can reveal subtle features in the terrain. Colors show the elevation as measured by SRTM. Colors range from green at the lowest elevations to reddish at the highest elevations. Shaded relief maps are commonly used in applications such as geologic mapping and land use planning.The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, uses 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. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging

  2. Colored Height and Shaded Relief, Central America

    Science.gov (United States)

    2002-01-01

    Panama, Costa Rica, Nicaragua, El Salvador, Honduras, Guatemala, Belize, southern Mexico and parts of Cuba and Jamaica are all seen in this image from NASA's Shuttle Radar Topography Mission. The dominant feature of the northern part of Central America is the Sierra Madre Range, spreading east from Mexico between the narrow Pacific coastal plain and the limestone lowland of the Yucatan Peninsula. Parallel hill ranges sweep across Honduras and extend south, past the Caribbean Mosquito Coast to lakes Managua and Nicaragua. The Cordillera Central rises to the south, gradually descending to Lake Gatun and the Isthmus of Panama. A highly active volcanic belt runs along the Pacific seaboard from Mexico to Costa Rica.High-quality satellite imagery of Central America has, until now, been difficult to obtain due to persistent cloud cover in this region of the world. The ability of SRTM to penetrate clouds and make three-dimensional measurements has allowed the generation of the first complete high-resolution topographic map of the entire region. This map was used to generate the image.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 north-south direction. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, to white at the highest elevations.For an annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site] (Large image: 9 mB jpeg)Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect

  3. World Globes, Shaded Relief and Colored Height

    Science.gov (United States)

    2003-01-01

    These images of the world were generated with data from the Shuttle Radar Topography Mission (SRTM). The SRTM Project has recently released a new global data set called SRTM30, where the original one arcsecond of latitude and longitude resolution (about 30 meters, or 98 feet, at the equator) was reduced to 30 arcseconds (about 928 meters, or 1496 feet.) These images were created from that data set and show the Earth as it would be viewed from a point in space centered over the Americas, Africa and the western Pacific.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 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.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise,Washington, D.C.Orientation: North toward the top Image Data: shaded and colored SRTM elevation model Original Data Resolution: SRTM 1 arcsecond (about 30 meters or 98 feet

  4. Reliability of conventional shade guides in teeth color determination.

    Science.gov (United States)

    Todorović, Ana; Todorović, Aleksandar; Gostović, Aleksandra Spadijer; Lazić, Vojkan; Milicić, Biljana; Djurisić, Slobodan

    2013-10-01

    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 deltaE value possible, indicating the most accurate shade match. The aim of this study was to evaluate the reliability of commercially available ceramic shade guides. 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: deltaL, deltaC, deltaH, deltaE, deltaElc. Based on these parameters spectrophotometer marks the shade matching as good, fair or adjust. 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. 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.

  5. ALTERNATIVE APIARIES SHADING ALTERNATIVAS DE SOMBREAMENTO PARA APIÁRIOS

    Directory of Open Access Journals (Sweden)

    Ricardo Costa Rodrigues de Camargo

    2011-07-01

    Full Text Available

    Beehives shading can be a strategy to minimize the heat stress suffered by bees in tropical regions such as the Northeastern Brazil. So, the objective of this study was to evaluate the influence of different beehives shading conditions on the development and quality of honey produced in Apis mellifera colonies. The experiment was carried out in an apiary owned by the Embrapa Meio-Norte, in Castelo do Piauí, Piauí State, Brazil. Bee colonies were placed under the shade provided by straw, polypropylene screen (80% shading, and trees, and under direct solar radiation, in a completely randomized design, with six replications. Data concerning beehives weight and breeding and feeding areas were analyzed by using the Kruskal-Wallis test. Honey samples collected from beehives were submitted to chemical analyses, in order to determine hydroxymethylfurfural (HMF, acidity, and diastase activities. It was observed that the artificial covers did not provide significant beneficial effects on the colonies development. Thermoregulation was impaired

  6. 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

  7. 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.

  8. 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 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.

  9. An hourly based performance comparison of an integrated micro-structural perforated shading screen with standard shading systems

    DEFF Research Database (Denmark)

    Appelfeld, David; McNeil, Andrew; Svendsen, Svend

    2012-01-01

    This article evaluates the performance of an integrated micro structural perforated shading screen (MSPSS). Such a system maintains a visual connection with the outdoors while imitating the shading functionality of a venetian blind. Building energy consumption is strongly influenced by the solar...... gains and heat transfer through the transparent parts of the fenestration systems. MSPSS is angular-dependent shading device that provides an effective strategy in the control of daylight, solar gains and overheating through windows. The study focuses on using direct experimental methods to determine bi......-directional transmittance properties of shading systems that are not included as standard shading options in readily available building performance simulation tools. The impact on the indoor environment, particularly temperature and daylight were investigated and compared to three other static complex fenestration systems...

  10. 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.

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

    Science.gov (United States)

    Manimaran, P; Sadan, D Sai

    2016-10-01

    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. 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. The objective of this study was to obtain a matching brand of material that has a particular shade tab among the brands used. To conclude, Ivoclar material matched the chromascop shade guide better than the vita material matched the vita classic shade guide.

  12. 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.

  13. 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.

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

    International Nuclear Information System (INIS)

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

    2017-01-01

    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. Temperature fluctuations inside savanna termite mounds: Do size and plant shade matter?

    Science.gov (United States)

    Ndlovu, M; Pérez-Rodríguez, A

    2018-05-01

    Mound building termites are key ecosystem engineers of subtropical savanna regions. Mounds allow termites to maintain suitable conditions for termite reproduction and food cultivation ('fungus gardens'). We studied how the internal mound temperature of Macrotermes natalensis, a dominant mound-building termite of the subtropical savanna of southern Africa, responds to a number of environmental variables. We used general additive mixed models (GAMM) to determine how external temperature, mound size (volume) and the amount of vegetation shade affects mound internal temperature over a 24-h period. Internal mound temperature varied daily following changes of the external temperature, although the range of variation was much smaller. Active termite mounds maintained a higher internal temperature than inactive ones, and mound activity reinforced the positive effect of mound size and moderated the negative effect of vegetation shade on internal temperatures. In turn, external temperature fluctuations equally affected active and inactive mounds. Large mounds maintained near optimal internal temperatures compared to smaller sized mounds. We therefore conclude that termite mound size is a stronger determinant of internal mound temperature stability compared to plant shade cover. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. 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%.

  17. 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.

  18. 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

  19. France, Shaded Relief and Colored Height

    Science.gov (United States)

    2003-01-01

    This image of France was generated with data from the Shuttle Radar Topography Mission (SRTM). For this broad view the resolution of the data was reduced to 6 arcseconds (about 185 meters north-south and 127 meters east-west), resampled to a Mercator projection, and the French border outlined. Even at this decreased resolution the variety of landforms comprising the country is readily apparent.The upper central part of this scene is dominated by the Paris Basin, which consists of a layered sequence of sedimentary rocks. Fertile soils over much of the area make good agricultural land. The Normandie coast to the upper left is characterized by high, chalk cliffs, while the Brittany coast (the peninsula to the left) is highly indented where deep valleys were drowned by the sea, and the Biscay coast to the southwest is marked by flat, sandy beaches.To the south, the Pyrenees form a natural border between France and Spain, and the south-central part of the country is dominated by the ancient Massif Central. Subject to volcanism that has only subsided in the last 10,000 years, these central mountains are separated from the Alps by the north-south trending Rhone River Basin.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

  20. 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...

  1. 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...

  2. 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....

  3. Analysis of the internal shading in a photovoltaic greenhouse tunnel

    Directory of Open Access Journals (Sweden)

    Alvaro Marucci

    2017-09-01

    Full Text Available In recent years, the increasing interest in energy production from renewable energy sources has led to photovoltaic elements being placed on greenhouse coverings. The shading of crops by these elements can, however, cause problems regarding the normal course of agricultural activity. All studies thus far on the application of photovoltaic (PV panels as a greenhouse covering material have focused on flat roof structures. Tunnel greenhouses, due to their curved shape, do not lend themselves easily to accommodating PV panels on even part of the cover. In this study, we analysed the shading variation inside a tunnel greenhouse that was produced by applying flexible and transparent PV panels in a checkerboard arrangement. The transparent flexible PV panels are manufactured using monocrystalline silicon cells, with an efficiency of 18%, incorporated into polymers with high resistance. The PV panel dimensions are 1.116×0.165 m. The simulation software Autodesk® Autocad2010® was used for this study. The variation and distribution of the shading percentage of PV panels were analysed in relation to the surface area affected by the photovoltaic roof, the total area of the greenhouse and the section of the greenhouse. In particular, we studied the variations in the percentage of shading and the size of the shaded area on the twenty-first day of each month of the year. The results show some regularity in the shading percentage, mainly due to the curvilinear shape of the section of the greenhouse. From mid-March to mid- September, the shading in the middle of the day is almost always inside the greenhouse. In the other months of the year, it is partly inside and partly outside the tunnel greenhouse. With the photovoltaic arrangement adopted, the percentage of shading during the year never exceeds 40%.

  4. Tied Up In Knots: Irony, Ambiguity, and the 'Difficult' Pleasures of FIFTY SHADES OF GREY

    OpenAIRE

    McCulloch, Richard

    2016-01-01

    Upon its release in February 2015, Sam Taylor-Johnson’s Fifty Shades of Grey met with vehement critical derision, finding itself reproached on both artistic and ideological grounds. While the precise focus of this indignation varied between reviews, complaints broadly fell into three categories: (1) it isn’t titillating enough (2) it\\ud is misogynistic, and (3) the love story and characters are clichéd and unrealistic.\\ud \\ud In this article, however, I demonstrate that the film is far more s...

  5. A Technique Using Calibrated Photography and Photoshop for Accurate Shade Analysis and Communication.

    Science.gov (United States)

    McLaren, Edward A; Figueira, Johan; Goldstein, Ronald E

    2017-02-01

    This article reviews the critical aspects of controlling the shade-taking environment and discusses various modalities introduced throughout the years to acquire and communicate shade information. Demonstrating a highly calibrated digital photographic technique for capturing shade information, this article shows how to use Photoshop® to standardize images and extract color information from the tooth and shade tab for use by a ceramist for an accurate shade-matching restoration.

  6. Climbing plants in a temperate rainforest understorey: searching for high light or coping with deep shade?

    Science.gov (United States)

    Valladares, Fernando; Gianoli, Ernesto; Saldaña, Alfredo

    2011-08-01

    While the climbing habit allows vines to reach well-lit canopy areas with a minimum investment in support biomass, many of them have to survive under the dim understorey light during certain stages of their life cycle. But, if the growth/survival trade-off widely reported for trees hold for climbing plants, they cannot maximize both light-interception efficiency and shade avoidance (i.e. escaping from the understorey). The seven most important woody climbers occurring in a Chilean temperate evergreen rainforest were studied with the hypothesis that light-capture efficiency of climbers would be positively associated with their abundance in the understorey. Species abundance in the understorey was quantified from their relative frequency and density in field plots, the light environment was quantified by hemispherical photography, the photosynthetic response to light was measured with portable gas-exchange analyser, and the whole shoot light-interception efficiency and carbon gain was estimated with the 3-D computer model Y-plant. Species differed in specific leaf area, leaf mass fraction, above ground leaf area ratio, light-interception efficiency and potential carbon gain. Abundance of species in the understorey was related to whole shoot features but not to leaf level features such as specific leaf area. Potential carbon gain was inversely related to light-interception efficiency. Mutual shading among leaves within a shoot was very low (<20 %). The abundance of climbing plants in this southern rainforest understorey was directly related to their capacity to intercept light efficiently but not to their potential carbon gain. The most abundant climbers in this ecosystem match well with a shade-tolerance syndrome in contrast to the pioneer-like nature of climbers observed in tropical studies. The climbers studied seem to sacrifice high-light searching for coping with the dim understorey light.

  7. Shade treatment affects structure and recovery of invasive C4 African grass Echinochloa pyramidalis.

    Science.gov (United States)

    López Rosas, Hugo; Moreno-Casasola, Patricia; Espejel González, Verónica E

    2015-03-01

    Echinochloa pyramidalis (Lam.) Hitchc. & Chase is an African grass with C4 photosynthesis, high biomass production, and high vegetative propagation that is tolerant to grazing and able to grow in flooded and dry conditions. Thus, it is highly invasive in tropical freshwater marshes where it is intentionally planted by ranchers to increase cattle production. This invasion is reducing plant biodiversity by increasing the invader's aerial coverage, changing wetland hydrology and causing soil physicochemical changes such as vertical accretion. Reducing the dominance of this species and increasing the density of native wetland species is a difficult, expensive, and time-consuming process. We applied a series of disturbance treatments aimed at eliminating E. pyramidalis and recovering the native vegetation of a partially invaded freshwater marsh. Treatments included physical (cutting, soil disking, transplanting individuals of the key native species Sagittaria lancifolia subsp. media (Micheli) Bogin, and/or reducing light with shade mesh) and/or chemical (spraying Round-Up™ herbicide) disturbances. At the end of the experiment, four of the five treatments used were effective in increasing the cover and biomass of native species and reducing that of E. pyramidalis. The combination of these treatments should be used to generate a proposal for the restoration of tropical wetlands invaded by non-native grasses. A promising treatment is using soil disked to soften the soil and destroy belowground structures such as roots and rhizomes. This treatment would be more promising if combined with the use of shade cloth. If it is desirable not to impact the soil or if there is not enough budget to make an effort to include active restoration disking soil, the use of shade cloth will suffice, although the recovery of native vegetation will be slower.

  8. Ecosystem Service of Shade Trees on Nutrient Cycling and Productivity of Coffee Agro-ecosystems

    Directory of Open Access Journals (Sweden)

    Rusdi Evizal

    2009-05-01

    Full Text Available Shade trees are significant in certification scheme of sustainable coffee production. They play an importance role on ecosystem functioning. This research is aimed to study ecosystem service of shade trees in some coffee agro-ecosystems particularly on nutrient cycling and land productivity. Four agro-ecosys tems of Robusta coffee (Coffea canephora, namely sun coffee (without shade trees, coffee shaded by Michelia champaca, coffee shaded by Gliricidia sepium, and coffee shaded by Erythrina indica are evaluated during 2007—2008. Smallholder coffee plantation in Sumberjaya Subdistrict, West Lampung, which managed under local standard were employed using Randomized Complete Block Design with 3 replications. The result showed that litter fall dynamic from shade trees and from coffee trees was influenced by rainfall. Shade trees decreased weed biomass while increased litter fall production. In dry season, shade trees decreased litter fall from coffee shaded by M. champaca. G. sepium and E. indica shaded coffee showed higher yield than sun coffee and M. champaca shaded coffee. Except for M. champaca shaded coffee, yield had positive correlation (r = 0.99 with litter fall production and had negative correlation (r = —0.82 with weed biomass production. Biomass production (litter fall + weed of sun coffee and shaded coffee was not significantly different. Litter fall of shade trees had significance on nutrient cycle mainly to balance the lost of nitrogen in coffee bean harvesting.Key Words: Coffea canephora, Michelia champaca, Gliricidia sepium, Erythrina indica, litter production, nutrient cycle, coffee yield.

  9. Shaded relief, color as height, Fiji

    Science.gov (United States)

    2000-01-01

    The Sovereign Democratic Republic of the Fiji Islands, commonly known as Fiji, is an independent nation consisting of some 332 islands surrounding the Koro Sea in the South Pacific Ocean. This topographic image shows Viti Levu, the largest island in the group. With an area of 10,429 square kilometers (about 4000 square miles), it comprises more than half the area of the Fiji Islands. Suva, the capital city, lies on the southeast shore. The Nakauvadra, the rugged mountain range running from north to south, has several peaks rising above 900 meters (about 3000 feet). Mount Tomanivi, in the upper center, is the highest peak at 1324 meters (4341 feet). The distinct circular feature on the north shore is the Tavua Caldera, the remnant of a large shield volcano that was active about 4 million years ago. Gold has been mined on the margin of the caldera since the 1930's. The Nadrau plateau is the low relief highland in the center of the mountain range. The coastal plains in the west, northwest and southeast account for only 15 percent of Viti Levu's area but are the main centers of agriculture and settlement.This shaded relief image was generated using topographic data from the Shuttle Radar Topography Mission. A computer-generated artificial light source illuminates the elevation data to produce a pattern of light and shadows. Slopes facing the light appear bright, while those facing away are shaded. On flatter surfaces, the pattern of light and shadows can reveal subtle features in the terrain. Colors show the elevation as measured by SRTM. Colors range from green at the lowest elevations top ink at the highest elevations. This image contains about 1300 meters(4300 feet) of total relief.The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses 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. The mission is designed to collect

  10. Las notas al pie en la traducción de Fifty Shades (Footnotes in the Translation of Fifty Shades

    Directory of Open Access Journals (Sweden)

    Xinia Valverde Jara

    2017-11-01

    Full Text Available Se analiza el recurso de las notas a pie de página insertas en la traducción independiente de literatura comercial en versión digital, de la trilogía Fifty Shades of Grey, Fifty Shades Darker y Fifty Shades Freed, de E. L. James. Se examina el grado de influencia de esos elementos extratextuales, y se concluye que todos ellos, organizados en un complejo proceso de traducción, en especial los del contexto de llegada, condicionan la estrategia traductológica. Abstract This study examines the use of footnotes as a translation strategy in the independent translation of commercial literature in digital format, based on the trilogy written by E. L. James, Fifty Shades of Grey, Fifty Shades Darker and Fifty Shades Freed. The analysis measures the influence of these extratextual elements within the complex translation process, specifically those of the target language context, and it is concluded that they condition the translation strategies used.

  11. South America, Shaded Relief and Colored Height

    Science.gov (United States)

    2003-01-01

    occurrence of simple erosional processes acting upon fairly uniform bedrock. Very smooth plateaus here are remnants of landforms most likely developed under geologic and environmental conditions much different than those present today. Fractures paralleling the coast are likely related to the opening of the Atlantic Ocean as South America drifted away from Africa, starting about 130 million years ago.To the southwest, broad lowlands host the Gran Chaco and Pampas regions. The depositional Gran Chaco drainages run almost exclusively from west to east from the Andes Mountains to the western edge of the Brazilian Highlands as a result of the much greater sediment supply from the Andes. Geologic processes on the Pampas are much more diverse, with stream erosion, stream deposition, subsidence, and wind processes all evident, even at the one-kilometer resolution shown here.Further south, Patagonia also displays these geologic processes plus more prominent volcanic features, including bumpy mesas, which are lava plateaus with small (and some large) volcanic cones. At its southern tip South America breaks into islands that include Tierra del Fuego and the Straits of Magellan.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

  12. 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.

  13. 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, PCavicide (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.

  14. Variation in light-intercepting area and photosynthetic rate of sun and shade shoots of two Picea species in relation to the angle of incoming light.

    Science.gov (United States)

    Ishii, Hiroaki; Hamada, Yoko; Utsugi, Hajime

    2012-10-01

    We investigated the effects of sun- and shade-shoot architecture on the photosynthetic rates of two Picea species by applying light from various angles in the laboratory. Compared with sun shoots, shade shoots were characterized by lower mass allocation per light-intercepting area, less leaf mass per shoot mass, less mutual shading among leaves and more efficient allocation of chlorophyll to photosynthesis. The shoot silhouette to total leaf area ratio (STAR(ϕ)) decreased with increasing shoot inclination angle (ϕ, the shoot axis angle relative to the projection plane) and was consistently higher for the shade shoots. Morphological and physiological characteristics of the shade shoots resulted in maximum rates of net photosynthesis at ϕ = 0° (P(max,0)) similar to that of the sun shoots when expressed on a leaf mass, total leaf area and chlorophyll basis. When the angle of incoming light was varied, P(max,ϕ) per total leaf area (P(max,ϕ )/A(T)) of the shade shoots increased linearly with increasing STAR(ϕ), while P(max,ϕ) per shoot silhouette area did not change. In contrast, the response of the sun shoots was non-linear, and an optimum angle of incoming light was determined. Our results suggest that shade-shoot morphology is adaptive for utilizing diffuse light incoming from various angles, while sun-shoot morphology is adaptive for avoiding the negative effects of strong direct radiation and for enhancing light diffusion into the canopy. We propose that the angle of incoming light should be taken into account when estimating photosynthetic rates of sun shoots of conifer trees in the field.

  15. 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.

  16. Why Shade Coffee Does Not Guarantee Biodiversity Conservation.

    Directory of Open Access Journals (Sweden)

    César Tejeda-Cruz

    2010-03-01

    Full Text Available Over the past decade, various strategies have emerged to address critical habitat losses through agricultural expansion. The promotion of shade-grown, premium-priced coffee has been highlighted as one alternative. Our research, based on interviews with farmers in Chiapas, disputes some of the assumptions made by shade coffee campaigners. Results revealed a predisposition to converting forest to shade coffee production due to the socioeconomic challenges farmers face and the potential for increasing incomes. To ensure that their well-being is improved at the same time as reducing environmental impacts, there is clearly a need to provide more detailed information on who is responsible for enforcing certification criteria and how this should take place.

  17. Optimising building net energy demand with dynamic BIPV shading

    International Nuclear Information System (INIS)

    Jayathissa, P.; Luzzatto, M.; Schmidli, J.; Hofer, J.; Nagy, Z.; Schlueter, A.

    2017-01-01

    Highlights: •Coupled analysis of PV generation and building energy using adaptive BIPV shading. •20–80% net energy saving compared to an equivalent static system. •The system can in some cases compensate for the entire heating/cooling/lighting load. •High resolution radiation simulation including impacts of module self shading. -- Abstract: The utilisation of a dynamic photovoltaic system for adaptive shading can improve building energy performance by controlling solar heat gains and natural lighting, while simultaneously generating electricity on site. This paper firstly presents an integrated simulation framework to couple photovoltaic electricity generation to building energy savings through adaptive shading. A high-resolution radiance and photovoltaic model calculates the photovoltaic electricity yield while taking into account partial shading between modules. The remaining solar irradiation that penetrates the window is used in a resistance-capacitance building thermal model. A simulation of all possible dynamic configurations is conducted for each hourly time step, of which the most energy efficient configuration is chosen. We then utilise this framework to determine the optimal orientation of the photovoltaic panels to maximise the electricity generation while minimising the building’s heating, lighting and cooling demand. An existing adaptive photovoltaic facade was used as a case study for evaluation. Our results report a 20–80% net energy saving compared to an equivalent static photovoltaic shading system depending on the efficiency of the heating and cooling system. In some cases the Adaptive Solar Facade can almost compensate for the entire energy demand of the office space behind it. The control of photovoltaic production on the facade, simultaneously with the building energy demand, opens up new methods of building management as the facade can control both the production and consumption of electricity.

  18. 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.

  19. Iterative CT shading correction with no prior information

    Science.gov (United States)

    Wu, Pengwei; Sun, Xiaonan; Hu, Hongjie; Mao, Tingyu; Zhao, Wei; Sheng, Ke; Cheung, Alice A.; Niu, Tianye

    2015-11-01

    Shading artifacts in CT images are caused by scatter contamination, beam-hardening effect and other non-ideal imaging conditions. The purpose of this study is to propose a novel and general correction framework to eliminate low-frequency shading artifacts in CT images (e.g. cone-beam CT, low-kVp CT) without relying on prior information. The method is based on the general knowledge of the relatively uniform CT number distribution in one tissue component. The CT image is first segmented to construct a template image where each structure is filled with the same CT number of a specific tissue type. Then, by subtracting the ideal template from the CT image, the residual image from various error sources are generated. Since forward projection is an integration process, non-continuous shading artifacts in the image become continuous signals in a line integral. Thus, the residual image is forward projected and its line integral is low-pass filtered in order to estimate the error that causes shading artifacts. A compensation map is reconstructed from the filtered line integral error using a standard FDK algorithm and added back to the original image for shading correction. As the segmented image does not accurately depict a shaded CT image, the proposed scheme is iterated until the variation of the residual image is minimized. The proposed method is evaluated using cone-beam CT images of a Catphan©600 phantom and a pelvis patient, and low-kVp CT angiography images for carotid artery assessment. Compared with the CT image without correction, the proposed method reduces the overall CT number error from over 200 HU to be less than 30 HU and increases the spatial uniformity by a factor of 1.5. Low-contrast object is faithfully retained after the proposed correction. An effective iterative algorithm for shading correction in CT imaging is proposed that is only assisted by general anatomical information without relying on prior knowledge. The proposed method is thus practical

  20. 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) 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...

  1. 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-...

  2. Evaluation of a standard shade guide for color change after disinfection.

    Science.gov (United States)

    Pohjola, Randall M; Hackman, Steven T; Browning, William D

    2007-09-01

    To determine if surface disinfectants cause a change in the shade perception of a standard Classic Vitapan shade guide. Consistency in shade selection for dental restorations involves many factors, and one of the most important is the shade tabs used in the selection process. Ten shade tabs each of shades B2, D2, C1, and A3.5 were selected from the Classic Vitapan shade guide (Vident). All tabs were measured with the EasyShade shade device (Vident) at baseline. Three tabs of each shade were set aside as controls. The other 7 tabs of each shade were treated with the surface disinfectant Cavicide (Metrex Research) for 480 cycles to simulate a year's usage. After each 480 cycles, all the tabs were again measured with the EasyShade. This process was repeated to simulate 2 and 3 years of use. The data were analyzed to calculate the delta E 2000 for any change. A statistically significant increase was observed in the value (L*) and chroma (C*) after 2 and 3 years of simulated treatments. These changes were not perceptible to the clinician. The authors suggest that 1 standard shade guide be set aside to compare against those in clinical use to determine when they should be replaced.

  3. 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-...... 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....

  4. Evaluation of an optimized shade guide made from porcelain powder mixtures.

    Science.gov (United States)

    Wang, Peng; Wei, Jiaqiang; Li, Qing; Wang, Yining

    2014-12-01

    Color errors associated with current shade guides and problems with color selection and duplication are still challenging for restorative dentists. The purpose of this study was to evaluate an optimized shade guide for visual shade duplication. Color distributions (L*, a*, and b*) of the maxillary left central incisors of 236 participants, whose ages ranged from 20 to 60, were measured with a spectrophotometer. Based on this color map, an optimized shade guide was designed with 14 shade tabs evenly distributed within the given color range of the natural incisors. The shade tabs were fabricated with porcelain powder mixtures and conventional laboratory procedures. A comparison of shade duplication by using the optimized and Vitapan Classical shade guides was conducted. Thirty Chinese participants were involved, and the colors of the left maxillary incisors were selected by using 2 shade guides. Metal ceramic crowns were fabricated according to the results of the shade selection. The colors of the shade tabs, natural teeth, and the ceramic crowns were measured with a spectrophotometer. The color differences among the natural teeth, the shade tabs, and the corresponding metal ceramic crowns were calculated and analyzed (α=.017). Significant differences were found in both phases of shade determination and shade duplication (P<.017). The total number of color errors with the optimized shade guide was 3.5, which was significantly less than that of Vitapan, 5.1 (P<.001). The optimized shade guide system improved performance not only in the color selection phase but also in the color of the fabricated crowns. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  5. Fault tolerant linear actuator

    Science.gov (United States)

    Tesar, Delbert

    2004-09-14

    In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.

  6. 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.

  7. 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,

  8. 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.

  9. Shades of African values and interests in Nigeria's international ...

    African Journals Online (AJOL)

    Shades of African values and interests in Nigeria's international relations: investigating the gains and the costs, 1960 – 2014. ... of policies that ensure that the country recovers all she lost in her years of naivety in I.R. The study adopted the historical methodology which emphasizes critical analyses and interpretation of facts.

  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. 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.

  12. Improvement of Shade Resilience in Photovoltaic Modules Using Buck Converters in a Smart Module Architecture

    NARCIS (Netherlands)

    Golroodbari, S. Mirbagheri; Waal, Arjen. de; Sark, Wilfried van

    2018-01-01

    Partial shading has a nonlinear effect on the performance of photovoltaic (PV) modules. Different methods of optimizing energy harvesting under partial shading conditions have been suggested to mitigate this issue. In this paper, a smart PV module architecture is proposed for improvement of shade

  13. 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 

  14. Performance of integrated systems of automated roller shade systems and daylight responsive dimming systems

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byoung-Chul; Choi, An-Seop; Jeong, Jae-Weon [Department of Architectural Engineering, Sejong University, Kunja-Dong, Kwangjin-Gu, Seoul (Korea, Republic of); Lee, Eleanor S. [Building Technologies Department, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2011-03-15

    Daylight responsive dimming systems have been used in few buildings to date because they require improvements to improve reliability. The key underlying factor contributing to poor performance is the variability of the ratio of the photosensor signal to daylight workplane illuminance in accordance with sun position, sky condition, and fenestration condition. Therefore, this paper describes the integrated systems between automated roller shade systems and daylight responsive dimming systems with an improved closed-loop proportional control algorithm, and the relative performance of the integrated systems and single systems. The concept of the improved closed-loop proportional control algorithm for the integrated systems is to predict the varying correlation of photosensor signal to daylight workplane illuminance according to roller shade height and sky conditions for improvement of the system accuracy. In this study, the performance of the integrated systems with two improved closed-loop proportional control algorithms was compared with that of the current (modified) closed-loop proportional control algorithm. In the results, the average maintenance percentage and the average discrepancies of the target illuminance, as well as the average time under 90% of target illuminance for the integrated systems significantly improved in comparison with the current closed-loop proportional control algorithm for daylight responsive dimming systems as a single system. (author)

  15. 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.

  16. 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....

  17. 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.

  18. 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.

  19. 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.

  20. Evaluation of Dental Shade Guide Variability Using Cross-Polarized Photography.

    Science.gov (United States)

    Gurrea, Jon; Gurrea, Marta; Bruguera, August; Sampaio, Camila S; Janal, Malvin; Bonfante, Estevam; Coelho, Paulo G; Hirata, Ronaldo

    2016-01-01

    This study evaluated color variability in the A hue between the VITA Classical (VITA Zahnfabrik) shade guide and four other VITA-coded ceramic shade guides using a Canon EOS 60D camera and software (Photoshop CC, Adobe). A total of 125 photographs were taken, 5 per shade tab for each of 5 shades (A1 to A4) from the following shade guides: VITA Classical (control), IPS e.max Ceram (Ivoclar Vivadent), IPS d.SIGN (Ivoclar Vivadent), Initial ZI (GC), and Creation CC (Creation Willi Geller). Photos were processed with Adobe Photoshop CC to allow standardized evaluation of hue, chroma, and value between shade tabs. None of the VITA-coded shade tabs fully matched the VITA Classical shade tab for hue, chroma, or value. The VITA-coded shade guides evaluated herein showed an overall unmatched shade in all tabs when compared with the control, suggesting that shade selection should be made using the guide produced by the manufacturer of the ceramic intended for the final restoration.

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

    International Nuclear Information System (INIS)

    Takahashi, Ryo; Todo, Yasuyuki

    2014-01-01

    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

  2. Attenuation of the jasmonate burst, plant defensive traits, and resistance to specialist monarch caterpillars on shaded common milkweed (Asclepias syriaca).

    Science.gov (United States)

    Agrawal, Anurag A; Kearney, Emily E; Hastings, Amy P; Ramsey, Trey E

    2012-07-01

    Plant responses to herbivory and light competition are often in opposing directions, posing a potential conflict for plants experiencing both stresses. For sun-adapted species, growing in shade typically makes plants more constitutively susceptible to herbivores via reduced structural and chemical resistance traits. Nonetheless, the impact of light environment on induced resistance has been less well-studied, especially in field experiments that link physiological mechanisms to ecological outcomes. Accordingly, we studied induced resistance of common milkweed (Asclepias syriaca, a sun-adapted plant), and linked hormonal responses, resistance traits, and performance of specialist monarch caterpillars (Danaus plexippus) in varying light environments. In natural populations, plants growing under forest-edge shade showed reduced levels of resistance traits (lower leaf toughness, cardenolides, and trichomes) and enhanced light-capture traits (higher specific leaf area, larger leaves, and lower carbon-to-nitrogen ratio) compared to paired plants in full sun. In a field experiment repeated over two years, only milkweeds growing in full sun exhibited induced resistance to monarchs, whereas plants growing in shade were constitutively more susceptible and did not induce resistance. In a more controlled field experiment, plant hormones were higher in the sun (jasmonic acid, salicylic acid, abscisic acid, indole acidic acid) and were induced by herbivory (jasmonic acid and abscisic acid). In particular, the jasmonate burst following herbivory was halved in plants raised in shaded habitats, and this correspondingly reduced latex induction (but not cardenolide induction). Thus, we provide a mechanistic basis for the attenuation of induced plant resistance in low resource environments. Additionally, there appears to be specificity in these interactions, with light-mediated impacts on jasmonate-induction being stronger for latex exudation than cardenolides.

  3. 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.

  4. 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

  5. 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.

  6. Topographical Hill Shading Map Production Based Tianditu (map World)

    Science.gov (United States)

    Wang, C.; Zha, Z.; Tang, D.; Yang, J.

    2018-04-01

    TIANDITU (Map World) is the public version of National Platform for Common Geospatial Information Service, and the terrain service is an important channel for users on the platform. With the development of TIANDITU, topographical hill shading map production for providing and updating global terrain map on line becomes necessary for the characters of strong intuition, three-dimensional sense and aesthetic effect. As such, the terrain service of TIANDITU focuses on displaying the different scales of topographical data globally. And this paper mainly aims to research the method of topographical hill shading map production globally using DEM (Digital Elevation Model) data between the displaying scales about 1 : 140,000,000 to 1 : 4,000,000, corresponded the display level from 2 to 7 on TIANDITU website.

  7. Height development of shade-tolerant conifer saplings in multiaged Acadian forest stands

    Science.gov (United States)

    Andrew R. Moores; Robert S. Seymour; Laura S. Kenefic

    2007-01-01

    Understory growth dynamics of northern conifer species were studied in four stands managed under multiaged silvicultural systems in eastern Maine. Height growth of Picea rubens Sarg., Abies balsamea (L.) Mill., and Tsuga canadensis (L.) Carr. saplings between 0.5 and 6.0 m in height was related to the proportion...

  8. Architecture of 53 rain forest tree species differing in adult stature and shade tolerance

    NARCIS (Netherlands)

    Poorter, L.; Bongers, F.J.J.M.; Sterck, F.J.; Wöll, H.

    2003-01-01

    Tree architecture determines a tree's light capture, stability, and efficiency of crown growth. The hypothesis that light demand and adult stature of tree species within a community, independently of each other, determine species' architectural traits was tested by comparing 53 Liberian rain forest

  9. 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...

  10. Production of tropical forage grasses under different shading levels

    Directory of Open Access Journals (Sweden)

    Francisco Eduardo Torres

    2017-12-01

    Full Text Available This study aimed to evaluate the forage production of three tropical forage grasses under different shading levels. The experiment was conducted in a greenhouse at Universidade Estadual de Mato Grosso do Sul, University Unit of Aquidauana (UEMS/UUA, in a soil classified as Ultisol sandy loam texture. The treatments consisted of three grasses species combinations (B. brizantha cv. Marandu, B. decumbens cv. Basilisck and Panicum maximum cv. Tanzania, submitted to four shading levels (0, 30, 50 and 75%, arranged in a completely randomized blocks design in a factorial 3 x 4, with eight replications. After harvest, the plants were separated into shoot and roots for determination of shoot fresh mass (SFM, shoot dry mass (SDM and roots dry mass production. After analysis of variance, the qualitative factor was subjected to comparison of averages by Tukey’s test, and the quantitative factor to analysis of polynomial regression, being interactions appropriately unfolded. It was verified that B. decumbens, by its linearly increasing production of forage and less decrease of root formation, is the most recommended for shading conditions compared to grasses Tanzania and Marandu.

  11. Effect of abutment shade, ceramic thickness, and coping type on the final shade of zirconia all-ceramic restorations: in vitro study of color masking ability.

    Science.gov (United States)

    Oh, Seon-Hee; Kim, Seok-Gyu

    2015-10-01

    The aim of the study was to evaluate the effect of abutment shade, ceramic thickness, and coping type on the final shade of zirconia all-ceramic restorations. Three different types of disk-shaped zirconia coping specimens (Lava, Cercon, Zirkonzahn: ø10 mm × 0.4 mm) were fabricated and veneered with IPS e.max Press Ceram (shade A2), for total thicknesses of 1 and 1.5 mm. A total of sixty zirconia restoration specimens were divided into six groups based on their coping types and thicknesses. The abutment specimens (ø10 mm × 7 mm) were prepared with gold alloy, base metal (nickel-chromium) alloy, and four different shades (A1, A2, A3, A4) of composite resins. The average L*, a*, b* values of the zirconia specimens on the six abutment specimens were measured with a dental colorimeter, and the statistical significance in the effects of three variables was analyzed by using repeated measures analysis of variance (α=.05).The average shade difference (ΔE) values of the zirconia specimens between the A2 composite resin abutment and other abutments were also evaluated. The effects of zirconia specimen thickness (Pabutment shade (Pabutments was higher (close to the acceptability threshold of 5.5 ΔE) than th ose between the A2 composite resin and other abutments. This in-vitro study demonstrated that abutment shade, ceramic thickness, and coping type affected the resulting shade of zirconia restorations.

  12. Role of riparian shade on the fish assemblage of a reservoir littoral

    Science.gov (United States)

    Raines, C. D.; Miranda, Leandro E.

    2016-01-01

    Research into the effects of shade on reservoir fish assemblages is lacking, with most investigations focused on streams. Unlike many streams, the canopy in a reservoir shades only a narrow fringe of water adjacent to the shoreline, and may not have the influential effect on the aquatic environment reported in streams. We compared fish assemblages between shaded and unshaded sites in a shallow reservoir. Overall species richness (gamma diversity) was higher in shaded sites, and fish assemblage composition differed between shaded and unshaded sites. Average light intensity was 66 % lower in shaded sites, and differences in average temperature and dissolved oxygen were small. Unlike streams where shade can have large effects on water physicochemistry, in reservoirs shade-related differences in fish assemblages seemed to be linked principally to differences in light intensity. Diversity in light intensity in shaded and unshaded sites in reservoirs can create various mosaics of light-based habitats that enable diversity of species assemblages. Managing to promote the habitat diversity provided by shade may require coping with the artificial nature of reservoir riparian zones and water level fluctuations.

  13. Using Google Earth to Assess Shade for Sun Protection in Urban Recreation Spaces: Methods and Results.

    Science.gov (United States)

    Gage, R; Wilson, N; Signal, L; Barr, M; Mackay, C; Reeder, A; Thomson, G

    2018-05-16

    Shade in public spaces can lower the risk of and sun burning and skin cancer. However, existing methods of auditing shade require travel between sites, and sunny weather conditions. This study aimed to evaluate the feasibility of free computer software-Google Earth-for assessing shade in urban open spaces. A shade projection method was developed that uses Google Earth street view and aerial images to estimate shade at solar noon on the summer solstice, irrespective of the date of image capture. Three researchers used the method to separately estimate shade cover over pre-defined activity areas in a sample of 45 New Zealand urban open spaces, including 24 playgrounds, 12 beaches and 9 outdoor pools. Outcome measures included method accuracy (assessed by comparison with a subsample of field observations of 10 of the settings) and inter-rater reliability. Of the 164 activity areas identified in the 45 settings, most (83%) had no shade cover. The method identified most activity areas in playgrounds (85%) and beaches (93%) and was accurate for assessing shade over these areas (predictive values of 100%). Only 8% of activity areas at outdoor pools were identified, due to a lack of street view images. Reliability for shade cover estimates was excellent (intraclass correlation coefficient of 0.97, 95% CI 0.97-0.98). Google Earth appears to be a reasonably accurate and reliable and shade audit tool for playgrounds and beaches. The findings are relevant for programmes focused on supporting the development of healthy urban open spaces.

  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 (Ptree 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. Assessment of microclimate conditions under artificial shades in a ginseng field.

    Science.gov (United States)

    Lee, Kyu Jong; Lee, Byun-Woo; Kang, Je Yong; Lee, Dong Yun; Jang, Soo Won; Kim, Kwang Soo

    2016-01-01

    Knowledge on microclimate conditions under artificial shades in a ginseng field would facilitate climate-aware management of ginseng production. Weather data were measured under the shade and outside the shade at two fields located in Gochang-gun and Jeongeup-si, Korea, in 2011 and 2012 seasons to assess temperature and humidity conditions under the shade. An empirical approach was developed and validated for the estimation of leaf wetness duration (LWD) using weather measurements outside the shade as inputs to the model. Air temperature and relative humidity were similar between under the shade and outside the shade. For example, temperature conditions favorable for ginseng growth, e.g., between 8°C and 27°C, occurred slightly less frequently in hours during night times under the shade (91%) than outside (92%). Humidity conditions favorable for development of a foliar disease, e.g., relative humidity > 70%, occurred slightly more frequently under the shade (84%) than outside (82%). Effectiveness of correction schemes to an empirical LWD model differed by rainfall conditions for the estimation of LWD under the shade using weather measurements outside the shade as inputs to the model. During dew eligible days, a correction scheme to an empirical LWD model was slightly effective (10%) in reducing estimation errors under the shade. However, another correction approach during rainfall eligible days reduced errors of LWD estimation by 17%. Weather measurements outside the shade and LWD estimates derived from these measurements would be useful as inputs for decision support systems to predict ginseng growth and disease development.

  16. Genotypic Diversity and Short-term Response to Shading Stress in a Threatened Seagrass: Does Low Diversity Mean Low Resilience?

    Directory of Open Access Journals (Sweden)

    Suzanna M. Evans

    2017-08-01

    Full Text Available Seagrasses that are predominantly clonal often have low levels of genetic variation within populations and predicting their response to changing conditions requires an understanding of whether genetic variation confers increased resistance to environmental stressors. A higher level of genetic diversity is assumed to benefit threatened species due to the increased likelihood of those populations having genotypes that can persist under environmental change. To test this idea, we conducted an in situ shading experiment with six geographically distinct meadows of the threatened seagrass Posidonia australis that vary in genetic diversity. Different genotypes within meadows varied widely in their physiological and growth responses to reduced light during a simulated short-term turbidity event. The majority of meadows were resistant to the sudden reduction in light availability, but a small subset of meadows with low genotypic diversity were particularly vulnerable to the early effects of shading, showing substantially reduced growth rates after only 3 weeks. Using the photosynthetic performance (maximum quantum yield of known genotypes, we simulated meadows of varying genetic diversity to show that higher diversity can increase meadow resilience to stress by ensuring a high probability of including a high-performing genotype. These results support the hypothesis that complementarity among genotypes enhances the adaptive capacity of a population, and have significant implications for the conservation of declining P. australis meadows close to the species range edge on the east coast of Australia, where the genotypic diversity is low.

  17. Genotypic Diversity and Short-term Response to Shading Stress in a Threatened Seagrass: Does Low Diversity Mean Low Resilience?

    Science.gov (United States)

    Evans, Suzanna M; Vergés, Adriana; Poore, Alistair G B

    2017-01-01

    Seagrasses that are predominantly clonal often have low levels of genetic variation within populations and predicting their response to changing conditions requires an understanding of whether genetic variation confers increased resistance to environmental stressors. A higher level of genetic diversity is assumed to benefit threatened species due to the increased likelihood of those populations having genotypes that can persist under environmental change. To test this idea, we conducted an in situ shading experiment with six geographically distinct meadows of the threatened seagrass Posidonia australis that vary in genetic diversity. Different genotypes within meadows varied widely in their physiological and growth responses to reduced light during a simulated short-term turbidity event. The majority of meadows were resistant to the sudden reduction in light availability, but a small subset of meadows with low genotypic diversity were particularly vulnerable to the early effects of shading, showing substantially reduced growth rates after only 3 weeks. Using the photosynthetic performance (maximum quantum yield) of known genotypes, we simulated meadows of varying genetic diversity to show that higher diversity can increase meadow resilience to stress by ensuring a high probability of including a high-performing genotype. These results support the hypothesis that complementarity among genotypes enhances the adaptive capacity of a population, and have significant implications for the conservation of declining P. australis meadows close to the species range edge on the east coast of Australia, where the genotypic diversity is low.

  18. 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

  19. Intolerant tolerance.

    Science.gov (United States)

    Khushf, G

    1994-04-01

    The Hyde Amendment and Roman Catholic attempts to put restrictions on Title X funding have been criticized for being intolerant. However, such criticism fails to appreciate that there are two competing notions of tolerance, one focusing on the limits of state force and accepting pluralism as unavoidable, and the other focusing on the limits of knowledge and advancing pluralism as a good. These two types of tolerance, illustrated in the writings of John Locke and J.S. Mill, each involve an intolerance. In a pluralistic context where the free exercise of religion is respected, John Locke's account of tolerance is preferable. However, it (in a reconstructed form) leads to a minimal state. Positive entitlements to benefits like artificial contraception or nontherapeutic abortions can legitimately be resisted, because an intolerance has already been shown with respect to those that consider the benefit immoral, since their resources have been coopted by taxation to advance an end that is contrary to their own. There is a sliding scale from tolerance (viewed as forbearance) to the affirmation of communal integrity, and this scale maps on to the continuum from negative to positive rights.

  20. Effects of shading on dry matter partitioning and yield of field-grown sunflower

    International Nuclear Information System (INIS)

    Villalobos, F.J.; Soriano, A.; Fereres, E.

    1992-01-01

    Crop simulation models require quantitative descriptions of the effects of irradiance on dry matter partition and yield. The objective of this work was to quantify the effects of reduced radiation intensity during different phenological stages on the growth, dry matter partitioning and grain numbers of sunflower (Helianthus annuus, L.). A field experiment was carried out in 1990 with 50 per cent shading treatments. The earliest treatment began at crop emergence while the latest ended at first anthesis. Shading had little effect on plant leaf area growth but reduced biomass and yield. The dry matter: radiation quotient and specific leaf area increased with shading. Grain number per head was decreased by shading, with the greatest effect occurring when shading was applied prior to anthesis. All shading treatments increased dry matter partitioning to stems, decreased assimilate partitioning to the heads and had no effect on the partitioning to leaves. (author)

  1. 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.

  2. 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.

  3. Experimental and Simulation for the Effect of Partial Shading on Solar Panel Performance

    Directory of Open Access Journals (Sweden)

    Emad Talib Hahsim

    2016-06-01

    Full Text Available Partial shading is one of the problems that affects the power production and the efficiency of photovoltaic module. A series of experimental work have been done of partial shading of monocrystalline PV module; 50W, Isc: 3.1A, Voc: 22V with 36 cells in series is achieved. Non-linear power output responses of the module are observed by applying various cases of partial shading (vertical and horizontal shading of solar cells in the module. Shading a single cell (corner cell has the greatest impact on output energy. Horizontal shading or vertical shading reduced the power from 41W to 18W at constant solar radiation 1000W/m2 and steady state condition. Vertical blocking a column of cells (9 cells in a module reduces the power from 41W to 18W (53% power reduction; while, blocking one or two cell in the row reduces the power from 41 W to 18W (53% power reduction. Shading three or four cells in the same row reduces the power from 41W to 1W or 0.006W (94% power reduction. A complete Matlab / Simulink model are achieved to simulate the effect of partial shading on power output of module. It is found that shading a single cell reduces the power from 50 W to 25 W (50% using Matlab/Simulink model. Comparisons have been made between the I-V and P-V characteristic curves from the simulation with the practical (experimental curves. The results showed that the percentage of error between the Simulink results and the corresponding experimental measurement are 22% without shading effect and, 32% with partial shading.

  4. 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 (ΔE clinical ) and laboratory shade-matching outcome (ΔE laboratory ) 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 ΔE clinical (6.5±2.4) and ΔE laboratory (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 ΔE clinical The patients, dental students, and supervising faculty members generally had positive opinions about the clinical shade-matching outcome, despite the increased ΔE clinical 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.

  5. 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...

  6. 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.

  7. VALIDATING the Accuracy of Sighten's Automated Shading Tool

    Energy Technology Data Exchange (ETDEWEB)

    2018-05-04

    Solar companies - including installers, financiers, and distributors - leverage Sighten software to deliver accurate shading calculations and solar proposals. Sighten recently partnered with Google Project Sunroof to provide automated remote shading analysis directly within the Sighten platform. The National Renewable Energy Laboratory (NREL), in partnership with Sighten, independently verified the accuracy of Sighten's remote-shading solar access values (SAVs) on an annual basis for locations in Los Angeles, California, and Denver, Colorado.

  8. Instream cover and shade mediate avian predation on trout in semi-natural streams

    Science.gov (United States)

    Penaluna, Brooke E.; Dunham, Jason B.; Noakes, David L. G.

    2015-01-01

    Piscivory by birds can be significant, particularly on fish in small streams and during seasonal low flow when available cover from predators can be limited. Yet, how varying amounts of cover may change the extent of predation mortality from avian predators on fish is not clear. We evaluated size-selective survival of coastal cutthroat trout (Oncorhynchus clarkii clarkii) in replicated semi-natural stream sections. These sections provided high (0.01 m2 of cover per m2 of stream) or low (0.002 m2 of cover per m2 of stream) levels of instream cover available to trout and were closed to emigration. Each fish was individually tagged, allowing us to track retention of individuals during the course of the 36-day experiment, which we attributed to survival from predators, because fish had no other way to leave the streams. Although other avian predators may have been active in our system and not detected, the only predator observed was the belted kingfisher Megaceryle alcyon, which is known to prey heavily on fish. In both treatments, trout >20.4 cm were not preyed upon indicating an increased ability to prey upon on smaller individuals. Increased availability of cover improved survival of trout by 12% in high relative to low cover stream sections. Trout also survived better in stream sections with greater shade, a factor we could not control in our system. Collectively, these findings indicate that instream cover and shade from avian predators can play an important role in driving survival of fish in small streams or during periods of low flow.

  9. Salt Tolerance

    OpenAIRE

    Xiong, Liming; Zhu, Jian-Kang

    2002-01-01

    Studying salt stress is an important means to the understanding of plant ion homeostasis and osmo-balance. Salt stress research also benefits agriculture because soil salinity significantly limits plant productivity on agricultural lands. Decades of physiological and molecular studies have generated a large body of literature regarding potential salt tolerance determinants. Recent advances in applying molecular genetic analysis and genomics tools in the model plant Arabidopsis thaliana are sh...

  10. Dental Shade Guide Variability for Hues B, C, and D Using Cross-Polarized Photography.

    Science.gov (United States)

    Sampaio, Camila S; Gurrea, Jon; Gurrea, Marta; Bruguera, August; Atria, Pablo J; Janal, Malvin; Bonfante, Estevam A; Coelho, Paulo G; Hirata, Ronaldo

    2018-04-20

    This study evaluated the color variability of hues B, C, and D between the VITA Classical shade guide (Vita Zahnfabrik) and four other VITA-coded ceramic shade guides using a digital camera (Canon EOS 60D) and computer software (Adobe Photoshop CC). A cross-polarizing filter was used to standardize external light sources influencing color match. A total of 275 pictures were taken, 5 per shade tab, for 11 shades (B1, B2, B3, B4, C1, C2, C3, C4, D2, D3, and D4), from the following shade guides: VITA Classical (control); IPS e.max Ceram (Ivoclar Vivadent); IPS d.SIGN (Ivoclar Vivadent); Initial ZI (GC); and Creation CC (Creation Willi Geller). Pictures were evaluated using Adobe Photoshop CC for standardization of hue, chroma, and value between shade tabs. The VITA-coded shade guides evaluated here showed an overall unmatched shade in all their tabs when compared to the control, suggesting that shade selection should be made with the corresponding manufacturer guide of the ceramic intended for the final restoration.

  11. Shading effect on generative characters of upland red rice of Southeast Sulawesi, Indonesia

    Science.gov (United States)

    Muhidin; Syam’un, E.; Kaimuddin; Musa, Y.; Sadimantara, G. R.; Usman; Leomo, S.; Rakian, T. C.

    2018-05-01

    Upland red rice (Oryza sativa) contains anthocyanin, a phenolic compounds that can act as antioxidants and functional food for human dietary. The content of functional food on upland red rice is influenced by shading condition, but the production is also influenced by environmental condition, especially the availability of light. The study aims is to assess and analyze the effect of shade on the growth and production of upland red rice. The research was conducted using the quantitative method to obtain the optimal shading condition that can increase the rice anthocyanin content and relatively high production. The research was arranged in split plot design, with shade as main plot and the different of cultivar as sub plot with three replications. The shading treatment consist of 4 levels as follows: n1=shade level 75%. The cultivar tested were (v1) = Labandiri, (v2) = Jangkobembe, (v3) = Ranggohitam, and (v4) = Paedara. The rice planted in between teak wood trees with different age and level of canopy. The research reveals that shades had an effect in decreasing plant production (the higher level of shade, the higher the decrease level of production), but the shades can improve the quality of red rice through the increase of anthocyanin content.

  12. Daylighting performance evaluation of a bottom-up motorized roller shade

    Energy Technology Data Exchange (ETDEWEB)

    Kapsis, K.; Athienitis, A.K.; Zmeureanu, R.G. [Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, QC (Canada); Tzempelikos, A. [School of Civil Engineering, Purdue University, West Lafayette, IN (United States)

    2010-12-15

    This paper presents an experimental and simulation study for quantifying the daylighting performance of bottom-up roller shades installed in office spaces. The bottom-up shade is a motorized roller shade that opens from top to bottom operating in the opposite direction of a conventional roller shade, so as to cover the bottom part of the window, while allowing daylight to enter from the top part of the window, reaching deeper into the room. A daylighting simulation model, validated with full-scale experiments, was developed in order to establish correlations between the shade position, outdoor illuminance and work plane illuminance for different outdoor conditions. Then, a shading control algorithm was developed for application in any location and orientation. The validated model was employed for a sensitivity analysis of the impact of shade optical properties and control on the potential energy savings due to the use of daylighting. The results showed that Daylight Autonomy for the bottom-up shade is 8-58% higher compared to a conventional roller shade, with a difference of 46% further away from the facade, where the use of electric lighting is needed most of the time. The potential reduction in energy consumption for lighting is 21-41%. (author)

  13. 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.

  14. Fifty Shades: ambivalence about birth control in an erotic bestseller and its cultural implications.

    Science.gov (United States)

    Maierhofer, Waltraud; Israel, Emanuella

    2017-04-01

    The Fifty Shades trilogy by E.L. James has taken the world by storm and become a cultural phenomenon. The lack of contraceptive use in the erotic fiction, first pointed out by bloggers, is analysed in this article and compared to medical information. James may be praised for sexualising condom use. However, her protagonist makes poor choices in terms of hormonal contraception and is negligent about its use, resulting in an unintended pregnancy and resolved in marital bliss and motherhood. What is of more interest here than a possible message about contraceptive use, is the outcome that the fiction's negligence in birth control and responsibility affirms an ideology in which female sexuality and sexual experimentation can only be tolerated within the context of procreation and affirmation of motherhood. Subsequently, the cultural significance of the trilogy's popularity and its tension between sexual exploration, birth control and fertility is explored. In a globally popular fantasy published more than five decades after the introduction of the pill, the protagonist's lack of attention to reliable birth control leads to a telling dichotomy that combines adventurous exploration of female sexuality and affirmation of the nuclear family.

  15. 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.

  16. Identity and diversity of coral endosymbionts (zooxanthellae) from three Palauan reefs with contrasting bleaching, temperature and shading histories.

    Science.gov (United States)

    Fabricius, K E; Mieog, J C; Colin, P L; Idip, D; van Oppen, M J H

    2004-08-01

    The potential of corals to associate with more temperature-tolerant strains of algae (zooxanthellae, Symbiodinium) can have important implications for the future of coral reefs in an era of global climate change. In this study, the genetic identity and diversity of zooxanthellae was investigated at three reefs with contrasting histories of bleaching mortality, water temperature and shading, in the Republic of Palau (Micronesia). Single-stranded conformation polymorphism and sequence analysis of the ribosomal DNA internal transcribed spacer (ITS)1 region was used for genotyping. A chronically warm but partly shaded coral reef in a marine lake that is hydrographically well connected to the surrounding waters harboured only two single-stranded conformation polymorphism profiles (i.e. zooxanthella communities). It consisted only of Symbiodinium D in all 13 nonporitid species and two Porites species investigated, with the remaining five Porites harbouring C*. Despite the high temperature in this lake (> 0.5 degrees above ambient), this reef did not suffer coral mortality during the (1998) bleaching event, however, no bleaching-sensitive coral families and genera occur in the coral community. This setting contrasts strongly with two other reefs with generally lower temperatures, in which 10 and 12 zooxanthella communities with moderate to low proportions of clade D zooxanthellae were found. The data indicate that whole coral assemblages, when growing in elevated seawater temperatures and at reduced irradiance, can be composed of colonies associated with the more thermo-tolerant clade D zooxanthellae. Future increases in seawater temperature might, therefore, result in an increasing prevalence of Symbiodinium phylotype D in scleractinian corals, possibly associated with a loss of diversity in both zooxanthellae and corals. Copyright 2004 Blackwell Publishing Ltd

  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. Maximum power point tracking of partially shaded solar photovoltaic arrays

    Energy Technology Data Exchange (ETDEWEB)

    Roy Chowdhury, Shubhajit; Saha, Hiranmay [IC Design and Fabrication Centre, Department of Electronics and Telecommunication Engineering, Jadavpur University (India)

    2010-09-15

    The paper presents the simulation and hardware implementation of maximum power point (MPP) tracking of a partially shaded solar photovoltaic (PV) array using a variant of Particle Swarm Optimization known as Adaptive Perceptive Particle Swarm Optimization (APPSO). Under partially shaded conditions, the photovoltaic (PV) array characteristics get more complex with multiple maxima in the power-voltage characteristic. The paper presents an algorithmic technique to accurately track the maximum power point (MPP) of a PV array using an APPSO. The APPSO algorithm has also been validated in the current work. The proposed technique uses only one pair of sensors to control multiple PV arrays. This result in lower cost and higher accuracy of 97.7% compared to earlier obtained accuracy of 96.41% using Particle Swarm Optimization. The proposed tracking technique has been mapped onto a MSP430FG4618 microcontroller for tracking and control purposes. The whole system based on the proposed has been realized on a standard two stage power electronic system configuration. (author)

  19. Infectious Tolerance

    OpenAIRE

    Jonuleit, Helmut; Schmitt, Edgar; Kakirman, Hacer; Stassen, Michael; Knop, Jürgen; Enk, Alexander H.

    2002-01-01

    Regulatory CD4+CD25+ T cells (Treg) are mandatory for maintaining immunologic self-tolerance. We demonstrate that the cell-cell contact–mediated suppression of conventional CD4+ T cells by human CD25+ Treg cells is fixation resistant, independent from membrane-bound TGF-β but requires activation and protein synthesis of CD25+ Treg cells. Coactivation of CD25+ Treg cells with Treg cell–depleted CD4+ T cells results in anergized CD4+ T cells that in turn inhibit the activation of conventional, ...

  20. 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...

  1. Infectious Tolerance

    Science.gov (United States)

    Jonuleit, Helmut; Schmitt, Edgar; Kakirman, Hacer; Stassen, Michael; Knop, Jürgen; Enk, Alexander H.

    2002-01-01

    Regulatory CD4+CD25+ T cells (Treg) are mandatory for maintaining immunologic self-tolerance. We demonstrate that the cell-cell contact–mediated suppression of conventional CD4+ T cells by human CD25+ Treg cells is fixation resistant, independent from membrane-bound TGF-β but requires activation and protein synthesis of CD25+ Treg cells. Coactivation of CD25+ Treg cells with Treg cell–depleted CD4+ T cells results in anergized CD4+ T cells that in turn inhibit the activation of conventional, freshly isolated CD4+ T helper (Th) cells. This infectious suppressive activity, transferred from CD25+ Treg cells via cell contact, is cell contact–independent and partially mediated by soluble transforming growth factor (TGF)-β. The induction of suppressive properties in conventional CD4+ Th cells represents a mechanism underlying the phenomenon of infectious tolerance. This explains previously published conflicting data on the role of TGF-β in CD25+ Treg cell–induced immunosuppression. PMID:12119350

  2. Black on White: or varying shades of grey? Indigenous Australian photomedia artists and the ‘making of’ Aboriginality

    NARCIS (Netherlands)

    Riphagen, M.

    2008-01-01

    In 2005 the Centre for Contemporary Photography in Melbourne presented the Indigenous photo-media exhibition Black on White. Promising to explore Indigenous perspectives on non-Aboriginality, its catalogue set forth two questions: how do Aboriginal artists see the people and culture that surrounds

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

    African Journals Online (AJOL)

    levels and solar radiation on the production of lactating dairy cows, is well .... period. Cortisol concentration (nmol /l ). No shade. SEa. Significance. Shade. 1984/85. 1985/86. 26.91 -+ .... Florida differ from local conditions, being subtropical with higher maximum .... A gradual rise in rectal temperature was, however, evident at.

  4. Segmentation-based retrospective shading correction in fluorescence microscopy E. coli images for quantitative analysis

    Science.gov (United States)

    Mai, Fei; Chang, Chunqi; Liu, Wenqing; Xu, Weichao; Hung, Yeung S.

    2009-10-01

    Due to the inherent imperfections in the imaging process, fluorescence microscopy images often suffer from spurious intensity variations, which is usually referred to as intensity inhomogeneity, intensity non uniformity, shading or bias field. In this paper, a retrospective shading correction method for fluorescence microscopy Escherichia coli (E. Coli) images is proposed based on segmentation result. Segmentation and shading correction are coupled together, so we iteratively correct the shading effects based on segmentation result and refine the segmentation by segmenting the image after shading correction. A fluorescence microscopy E. Coli image can be segmented (based on its intensity value) into two classes: the background and the cells, where the intensity variation within each class is close to zero if there is no shading. Therefore, we make use of this characteristics to correct the shading in each iteration. Shading is mathematically modeled as a multiplicative component and an additive noise component. The additive component is removed by a denoising process, and the multiplicative component is estimated using a fast algorithm to minimize the intra-class intensity variation. We tested our method on synthetic images and real fluorescence E.coli images. It works well not only for visual inspection, but also for numerical evaluation. Our proposed method should be useful for further quantitative analysis especially for protein expression value comparison.

  5. Effects of shading on starch pasting characteristics of indica hybrid rice (Oryza sativa L..

    Directory of Open Access Journals (Sweden)

    Li Wang

    Full Text Available Rice is an important staple crop throughout the world, but environmental stress like low-light conditions can negatively impact crop yield and quality. Using pot experiments and field experiments, we studied the effects of shading on starch pasting viscosity and starch content with six rice varieties for three years, using the Rapid Visco Analyser to measure starch pasting viscosity. Shading at different growth stages and in different rice varieties all affected the starch pasting characteristics of rice. The effects of shading on starch pasting viscosity at middle and later growth stages were greater than those at earlier stages. Shading enhanced breakdown but reduced hold viscosity and setback at tillering-elongation stage. Most pasting parameters changed significantly with shading after elongation stage. Furthermore, the responses of different varieties to shading differed markedly. The change scope of starch pasting viscosity in Dexiang 4103 was rather small after heading, while that in IIyou 498 and Gangyou 906 was small before heading. We observed clear tendencies in peak viscosity, breakdown, and pasting temperature of the five rice varieties with shading in 2010 and 2011. Correlation analysis indicated that the rice amylose content was negatively correlated with breakdown, but was positively correlated with setback. Based on our results, IIyou 498, Gangyou 906, and Dexiang 4103 had higher shade endurance, making these varieties most suitable for high-quality rice cultivation in low-light regions.

  6. Effects of shading on starch pasting characteristics of indica hybrid rice (Oryza sativa L.).

    Science.gov (United States)

    Wang, Li; Deng, Fei; Ren, Wan-Jun; Yang, Wen-Yu

    2013-01-01

    Rice is an important staple crop throughout the world, but environmental stress like low-light conditions can negatively impact crop yield and quality. Using pot experiments and field experiments, we studied the effects of shading on starch pasting viscosity and starch content with six rice varieties for three years, using the Rapid Visco Analyser to measure starch pasting viscosity. Shading at different growth stages and in different rice varieties all affected the starch pasting characteristics of rice. The effects of shading on starch pasting viscosity at middle and later growth stages were greater than those at earlier stages. Shading enhanced breakdown but reduced hold viscosity and setback at tillering-elongation stage. Most pasting parameters changed significantly with shading after elongation stage. Furthermore, the responses of different varieties to shading differed markedly. The change scope of starch pasting viscosity in Dexiang 4103 was rather small after heading, while that in IIyou 498 and Gangyou 906 was small before heading. We observed clear tendencies in peak viscosity, breakdown, and pasting temperature of the five rice varieties with shading in 2010 and 2011. Correlation analysis indicated that the rice amylose content was negatively correlated with breakdown, but was positively correlated with setback. Based on our results, IIyou 498, Gangyou 906, and Dexiang 4103 had higher shade endurance, making these varieties most suitable for high-quality rice cultivation in low-light regions.

  7. Shade factors for 149 taxa of in-leaf urban trees in the USA

    Science.gov (United States)

    E. Gregory McPherson; Qingfu Xiao; Natalie S. van Doorn; Nels Johnson; Shannon Albers; Paula J. Peper

    2018-01-01

    Shade factors, defined as the percentage of sky covered by foliage and branches within the perimeter of individual tree crowns, have been used to model the effects of trees on air pollutant uptake, building energy use and rainfall interception. For the past 30 years the primary source of shade factors was a database containing values from 47 species. In most...

  8. 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

  9. 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,

  10. [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.

  11. Growth and production of new superior rice varieties in the shade intensity

    Science.gov (United States)

    Alridiwirsah; Harahap, E. M.; Akoeb, E. N.; Hanum, H.

    2018-02-01

    Shade intensity is one of the most important requirements for plant growth, affecting growth, development, survival, and crop productivity. This study aims to evaluate the growth and productiom of New Superior Rice Varieties In The shade Intensity. This study was conducted in Balai Pengkajian Teknologi Pertanian, Pagar Merbau, Deli Serdang, North Sumatra. The research used completely randomized design with twofactors. The shade intensity (N) were 25%, 50% and no shade intensity as a control. Whereas new superior rice varieties were V1: Inpara 2, V2: Suluttan Unsrat 2, V3: Inpari Mugibat, V4: Inpari Sidenuk, V5: Mekongga, V6: Ciherang, V7:Inpari 10, V8: Inpari 3, V9: Inpari 4, V10: Inpari 30, dan V11: Cibogo. The result indicated that new superior rice varietiesshowedsignificant effectonthe growth and productionvariablesuch as leaf area, where Inpari Sidenuk variety was the highest among the varieties. Total chorophyll, the highest was found on Inpari variety. Number of tillers and plant height where the highest was found on Ciherang variety. The shade intensity showed significant effect on leaf area, where 25% shade intensity was the highest. Total chlorophyll, the highest was found on 50% shade intensity, number of tillers, the highest was found on no shade intensity.

  12. Development and Performance Evaluation of a Rain Shade for a low ...

    African Journals Online (AJOL)

    Aderoju Tomiwa

    for a low scale agricultural produce, The rain shade consists of a geared D. C motor, 12V battery, ... rain shade was embarked on in this research work. ... (9) Face width, b. +. 5mm (10). Determination of weight acting on the Extension. Arm: The measured weight of the polyester fabric equals 14.7N, while the combined ...

  13. 29 CFR 780.506 - Dependence of exemption on shade-grown tobacco operations.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Dependence of exemption on shade-grown tobacco operations. 780.506 Section 780.506 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION....506 Dependence of exemption on shade-grown tobacco operations. The exemption provided by section 13(a...

  14. The effect of shade on chlorophyll and anthocyanin content of upland red rice

    Science.gov (United States)

    Muhidin; Syam'un, E.; Kaimuddin; Musa, Y.; Sadimantara, G. R.; Usman; Leomo, S.; Rakian, T. C.

    2018-02-01

    Upland red rice (Oryza sativa) is a staple food and contains anthocyanin, which can act as antioxidants, plays an important role both for the plant itself and for human health. Levels of antioxidants in rice can be affected by the availability of light. The results showed that the difference of shade, cultivar, and interaction both significantly affect the content of chlorophyll a, chlorophyll b and total chlorophyll. The results also showed that shade could increase chlorophyll in all cultivars tested. The highest levels of chlorophyll a were present in the moderate shade level (n2), then decreased at the shelter level (n3) and increased again at high levels (n4). While on chlorophyll content b, it appears that shade increased chlorophyll b in all cultivars tested and this increase was linear to the increase of shade. The shade treatment may increase the anthocyanin content and the increase depending on the type of cultivar. Increased levels of anthocyanin highest due to shade occurred on Jangkobembe cultivar. The original level of anthocyanin on Jangkobembe cultivar averaged 0.096 mg g-1 increased to 2.487 mg g-1 or increased 26 fold. It is concluded that the shade had a significant effect on the chlorophyll and anthocyanin content.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    , 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...

  16. 29 CFR 780.505 - Definition of “shade-grown tobacco.”

    Science.gov (United States)

    2010-07-01

    ... Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and... 29 Labor 3 2010-07-01 2010-07-01 false Definition of âshade-grown tobacco.â 780.505 Section 780.505 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR...

  17. 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.

  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. Effect of ceramic thickness and cement shade on the final shade after bonding using the 3D master system: a laboratory study.

    Science.gov (United States)

    Montero, Javier; Gómez-Polo, Cristina

    2016-06-01

    The final color of a ceramic restoration is influenced by both the ceramic thickness and the cement shade. This study aims to evaluate the color stability according to the 3D Master System of e.max ceramic discs after bonding with different shades of luting agents. A total of 120 e.max.Press 2M1 HT ceramic discs (60 discs of 1-mm thick and 60 discs of 0.5 mm thick) and three different values of Variolink Veneer cement were used (-3, 0, +3) for the cementation process. An Easyshade compact device was used to measure color shade tabs, according to the 3D Master System, on the discs both before and after the cementation protocols. Bivariate and multivariate analyses were carried out with the spss v.21. After bonding with the different luting agents, only 30% remained as 2M1: specifically, 22% of the thinner discs and 37.3% of the thicker discs. In general, the effect of bonding increased the value and the chroma of the shade to a significant extent. Regression analyses revealed that the most significant predictor for all color parameters was cement shade, the thinner disc group bonded with -3 cement being the most unstable subgroup. According to the 3D Master System, the shade of the luting agent was the main predictor of the final color. However, the final color seems to be somewhat unpredictable, at least according to the modulating factors evaluated in the present study.

  20. The effects of providing portable shade at pasture on dairy cow behavior and physiology.

    Science.gov (United States)

    Palacio, S; Bergeron, R; Lachance, S; Vasseur, E

    2015-09-01

    Access to pasture has advantages for cows such as reduced lameness and improved udder health, but also may expose cows to stressors such as extreme heat. The objective of this study was to understand how portable shade affected physiological and behavioral responses of pastured dairy cows in a Canadian summer. Over 8wk, a total of 24 lactating Holstein cows were separated into 2 treatments, one with access to shade and a control without access to shade. The cows were pastured in groups of 4, with 3 field sections per treatment. Instantaneous scan sampling of behaviors (drinking, lying, grazing, other) performed in the shade or not were recorded every 5min for 3h/d during the hottest part of the day (peak hours: 1130-1530h) 3d/wk. Ambient temperature, humidity, and vaginal temperature were recorded at 10-min intervals. Daily milk production was also recorded. Differences between treatments by week were analyzed using the generalized linear mixed model with group as random effect and treatment as fixed effect. Cows with shade access were observed at the water trough up to 6.42 times less and lying down up to 1.75 times more. Cows with shade access grazed up to 1.5 times more but only when the temperature-humidity index was above their comfort threshold (≥72) during the hottest part of the day (wk 2). Cows sought shade when it was made available, but spent less than half of their time observed (%) in the shade (40.8±4.67) with the exception of wk 2 when most of the time was spent under the shade (74.3±4.77). Daily lying time was highest during peak hours for cows with shade access. However, no overall difference in total lying time between the 2 treatments was observed. No differences were found in vaginal temperature or milk production between treatments with the exception of wk 1 for daily milk production, which was higher for cows in the control treatment. In conclusion, cows sought shade when it was provided at pasture, whereas cows without access to shade

  1. World in Mercator Projection, Shaded Relief and Colored Height

    Science.gov (United States)

    2003-01-01

    This image of the world was generated with data from the Shuttle Radar Topography Mission (SRTM). The SRTM Project has recently released a new global data set called SRTM30, where the original one arcsecond of latitude and longitude resolution (about 30 meters, or 98 feet, at the equator) was reduced to 30 arcseconds (about 928 meters, or 1496 feet.) This image was created from that data set and shows the world between 60 degrees south and 60 degrees north latitude, covering 80% of the Earth's land mass. The image is in the Mercator Projection commonly used for maps of the world.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 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.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise,Washington, D.C.Orientation: North toward the top, Mercator projection Image Data: shaded and colored SRTM

  2. Shaded Relief with Color as Height, California Mosaic

    Science.gov (United States)

    2002-01-01

    The diversity of landforms that make up the state of California is evident in this new rendition of the 3-D topography of the state. The Central Valley, flanked on the east by the Sierra Nevada, dominates the scene with San Francisco and Monterey Bays clearly visible at left center. Other features of interest include Lake Tahoe at the edge to the right of San Francisco, Mono Lake below Lake Tahoe, and the Salton Sea at the lower right. The prominent sideways 'V' in the southern part of the state is the intersection of the Garlock and San Andreas Faults - to the east is the Mojave Desert. Offshore are the Channel Islands and to the right of them lies the city of Los Angeles.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction. North-facing slopes appear bright and south-facing slopes appear dark. Color coding is directly related to topographic height, with blue and green at the lower elevations, rising through yellow and brown to white at the highest elevations.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 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.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science

  3. Alpine Fault, New Zealand, SRTM Shaded Relief and Colored Height

    Science.gov (United States)

    2005-01-01

    The Alpine fault runs parallel to, and just inland of, much of the west coast of New Zealand's South Island. This view was created from the near-global digital elevation model produced by the Shuttle Radar Topography Mission (SRTM) and is almost 500 kilometers (just over 300 miles) wide. Northwest is toward the top. The fault is extremely distinct in the topographic pattern, nearly slicing this scene in half lengthwise. In a regional context, the Alpine fault is part of a system of faults that connects a west dipping subduction zone to the northeast with an east dipping subduction zone to the southwest, both of which occur along the juncture of the Indo-Australian and Pacific tectonic plates. Thus, the fault itself constitutes the major surface manifestation of the plate boundary here. Offsets of streams and ridges evident in the field, and in this view of SRTM data, indicate right-lateral fault motion. But convergence also occurs across the fault, and this causes the continued uplift of the Southern Alps, New Zealand's largest mountain range, along the southeast side of the fault. Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast (image top to bottom) 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

  4. Shaded Relief with Color as Height, St. Louis, Missouri

    Science.gov (United States)

    2002-01-01

    The confluence of the Mississippi, Missouri and Illinois rivers are shown in this view of the St. Louis area from the Shuttle Radar Topography Mission. The Mississippi flows from the upper left of the image and first meets the Illinois, flowing southward from the top right. It then joins the Missouri, flowing from the west across the center of the picture. The rivers themselves appear black here, and one can clearly see the green-colored floodplains in which they are contained. These floodplains are at particular risk during times of flooding. The Mississippi forms the state boundary between Illinois (to the right) and Missouri (to the left), with the city of St. Louis located on the Mississippi just below the point where it meets the Missouri. This location at the hub of the major American waterways helped establish St. Louis' reputation as the 'Gateway to the West.'Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction. North-facing slopes appear bright and south-facing slopes appear dark. Color coding is directly related to topographic height, with blue and green at the lower elevations, rising through yellow and brown to white at the highest elevations.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

  5. Shenandoah National Park, Virginia, Shaded Relief with Height as Color

    Science.gov (United States)

    2003-01-01

    Shenandoah National Park lies astride part of the Blue Ridge Mountains, which form the southeastern range of the greater Appalachian Mountains in Virginia. The park is well framed by this one-degree of latitude (38-39 north) by one-degree of longitude (78-79 west) cell of Shuttle Radar Topography Mission data, and it appears here as the most prominent ridge trending diagonally across the scene. Skyline Drive, a 169-kilometer (105-mile) road that winds along the crest of the mountains through the length the park, provides vistas of the surrounding landscape. The Shenandoah River flows through the valley to the west, with Massanutten Mountain standing between the river's north and south forks. Unusually pronounced meanders of both river forks are very evident near the top center of this scene. Massanutten Mountain itself is an unusually distinctive landform also, consisting of highly elongated looping folds of sedimentary rock. The rolling Piedmont country lies to the southeast of the park, with Charlottesville located at the bottom center of the scene.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, to bluish-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 February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60

  6. SRTM Colored Height and Shaded Relief: Lava plateaus in Argentina

    Science.gov (United States)

    2001-01-01

    All of the major landforms relate to volcanism and/or erosion in this Shuttle Radar Topography Mission scene of Patagonia, near La Esperanza, Argentina. The two prominent plateaus once formed a continuous surface that extended over much of this region. Younger volcanoes have grown through and atop the plateau, and one just south of this scene has sent a long, narrow flow down a stream channel (lower left). The topographic pattern shows that streams dominate the erosion processes in this arid environment even though wind is known to move substantial amounts of sediment here.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear dark, as would be the case at noon at this latitude in the southern hemisphere. Color-coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, to white at the highest elevations.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 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 three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (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.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.Size: 62.4 by 88.8 kilometers

  7. SRTM Colored Height and Shaded Relief: Near Zapala, Argentina

    Science.gov (United States)

    2001-01-01

    Topographic data provided by the Shuttle Radar Topography Mission can provide many clues to geologic history and processes. This view of an area southwest of Zapala, Argentina, shows a wide diversity of geologic features. The highest peaks (left) appear to be massive (un-layered)crystalline rocks, perhaps granites. To their right (eastward) are tilted and eroded layered rocks, perhaps old lava flows, forming prominent ridges. Farther east and south, more subtle and curvilinear ridges show that the rock layers have not only been tilted but also folded. At the upper right, plateaus that cap the underlying geologic complexities are more recent lava flows - younger than the folding, but older than the current erosional pattern. Landforms in the southeast (lower right) and south-central areas appear partially wind sculpted.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear dark, as would be the case at noon at this latitude in the southern hemisphere. Color-coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, to white at the highest elevations.Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard Space Shuttle Endeavour, launched on February 11,2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on Space Shuttle Endeavour in 1994. Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National

  8. SRTM Colored Height and Shaded Relief: Las Bayas, Argentina

    Science.gov (United States)

    2001-01-01

    The interplay of volcanism, stream erosion and landslides is evident in this Shuttle Radar Topography Mission view of the eastern flank of the Andes Mountains, southeast of San Carlos de Bariloche, Argentina. Older lava flows emanating from the Andes once covered much of this area. Younger, local volcanoes (seen here as small peaks) then covered parts of the area with fresh, erosion resistant flows (seen here as very smooth surfaces). Subsequent erosion has created fine patterns on the older surfaces (bottom of the image) and bolder, irregular patterns through and around the younger surfaces (upper center and right center). Meanwhile, where a large stream immediately borders the resistant plateau (center of the image), lateral erosion has undercut the resistant plateau causing slivers of it to fall into the stream channel. This scene well illustrate show topographic data alone can reveal some aspects of recent geologic history.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear dark, as would be the case at noon at this latitude in the southern hemisphere. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, 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 February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and

  9. Optimization of partially shaded PV array using a modified P&O MPPT algorithm

    Directory of Open Access Journals (Sweden)

    Abdelaziz YOUCEF

    2016-07-01

    Full Text Available A photovoltaic (PV array generated power is directly affected by temperature, solar irradiation, shading, and array configuration. In practice, PV arrays could be partially shaded by could, buildings, trees and other utilities. In this case, multiple maximums appear in the P-V curve, a global maximum and one or several local maximums. The “perturb and observe“ (P&O maximum power point tracking (MPPT algorithm cannot differentiate between a global and a local maximum and it is therefore ineffective when partial shading occurs. First, this paper presents an original mathematical model of the P-V curve of a partially shaded PV array, that was used to perform a simulation study in order to show the P&O algorithm inability to track the global MPP of a PV array solar system under partial shading for low shading irradiation levels, then an adaptation sub algorithm is proposed to be added to the P&O algorithm in order to give it the ability to track the global MPP. This sub algorithm moves the operating point imposed by the partial shading configuration to a point in the vicinity of the global MPP in order to be easily tracked by the P&O algorithm. In the simulation, a PV array with a hundred modules has been considered by using a light, a medium then a severe shading configuration. The results obtained indicate that the proposed modified P&O algorithm is able to track the global MPP for the considered shading configurations and for any shading irradiation level.

  10. 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.

  11. 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.

  12. 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...... with the prototype façade. This layout allowed the use of the same orientation and surroundings for both façades. The working plane illuminance was measured over several months and the measurements were accompanied with annual daylight simulations. The prototype system improved the daylighting conditions compared...

  13. Mt. Elgon, Africa, Shaded Relief and Colored Height

    Science.gov (United States)

    2004-01-01

    The striking contrast of geologic structures in Africa is shown in this shaded relief image of Mt. Elgon on the left and a section of the Great Rift Valley on the right. Mt. Elgon is a solitary extinct volcano straddling the border between Uganda and Kenya, and at 4,321 meters (14,178 feet) tall is the eighth highest mountain in Africa. It is positioned on the Pre-Cambriam bedrock of the Trans Nzoia Plateau, and is similar to other such volcanoes in East Africa in that it is associated with the formation of the Rift Valley. However one thing that sets Mt. Elgon apart is its age. Although there is no verifiable evidence of its earliest volcanic activity, Mt. Elgon is estimated to be at least 24 million years old, making it the oldest extinct volcano in East Africa. This presents a striking comparison to Mt. Kilimanjaro, the highest mountain in Africa at 5,895 meters (19,341 feet), which is just over one million years old. Judging by the diameter of its base, it is a common belief among geological experts that Mt. Elgon was once the highest mountains in Africa, however erosion has played a significant role in reducing the height to its present value. Juxtaposed with this impressive mountain is a section of the Great Rift Valley, a geological fault system that extends for about 4,830 kilometers (2,995 miles) from Syria to central Mozambique. Erosion has concealed some sections, but in some sections like that shown here, there are sheer cliffs several thousand feet high. The present configuration of the valley, which dates from the mid-Pleistocene epoch, results from a rifting process associated with thermal currents in the Earth's mantle. 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

  14. Time-varying BRDFs.

    Science.gov (United States)

    Sun, Bo; Sunkavalli, Kalyan; Ramamoorthi, Ravi; Belhumeur, Peter N; Nayar, Shree K

    2007-01-01

    The properties of virtually all real-world materials change with time, causing their bidirectional reflectance distribution functions (BRDFs) to be time varying. However, none of the existing BRDF models and databases take time variation into consideration; they represent the appearance of a material at a single time instance. In this paper, we address the acquisition, analysis, modeling, and rendering of a wide range of time-varying BRDFs (TVBRDFs). We have developed an acquisition system that is capable of sampling a material's BRDF at multiple time instances, with each time sample acquired within 36 sec. We have used this acquisition system to measure the BRDFs of a wide range of time-varying phenomena, which include the drying of various types of paints (watercolor, spray, and oil), the drying of wet rough surfaces (cement, plaster, and fabrics), the accumulation of dusts (household and joint compound) on surfaces, and the melting of materials (chocolate). Analytic BRDF functions are fit to these measurements and the model parameters' variations with time are analyzed. Each category exhibits interesting and sometimes nonintuitive parameter trends. These parameter trends are then used to develop analytic TVBRDF models. The analytic TVBRDF models enable us to apply effects such as paint drying and dust accumulation to arbitrary surfaces and novel materials.

  15. 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.

  16. TOLERANCE SENSITIVITY ANALYSIS: THIRTY YEARS LATER

    Directory of Open Access Journals (Sweden)

    Richard E. Wendell

    2010-12-01

    Full Text Available Tolerance sensitivity analysis was conceived in 1980 as a pragmatic approach to effectively characterize a parametric region over which objective function coefficients and right-hand-side terms in linear programming could vary simultaneously and independently while maintaining the same optimal basis. As originally proposed, the tolerance region corresponds to the maximum percentage by which coefficients or terms could vary from their estimated values. Over the last thirty years the original results have been extended in a number of ways and applied in a variety of applications. This paper is a critical review of tolerance sensitivity analysis, including extensions and applications.

  17. Influence of varying light regimes on photosynthesis and related ...

    African Journals Online (AJOL)

    Administrator

    and water use efficiency showed significantly (P < 0.05) higher values for shade ... Key words: Net carbon exchange, forest tree seedlings, shade, Warburgia ugandensis, .... infra-red gas analyser (IRGA-ADC. model LCA-2, The Analytical.

  18. Improvement of Shade Resilience in Photovoltaic Modules Using Buck Converters in a Smart Module Architecture

    Directory of Open Access Journals (Sweden)

    S. Zahra Mirbagheri Golroodbari

    2018-01-01

    Full Text Available Partial shading has a nonlinear effect on the performance of photovoltaic (PV modules. Different methods of optimizing energy harvesting under partial shading conditions have been suggested to mitigate this issue. In this paper, a smart PV module architecture is proposed for improvement of shade resilience in a PV module consisting of 60 silicon solar cells, which compensates the current drops caused by partial shading. The architecture consists of groups of series-connected solar cells in parallel to a DC-DC buck converter. The number of cell groups is optimized with respect to cell and converter specifications using a least-squares support vector machine method. A generic model is developed to simulate the behavior of the smart architecture under different shading patterns, using high time resolution irradiance data. In this research the shading patterns are a combination of random and pole shadows. To investigate the shade resilience, results for the smart architecture are compared with an ideal module, and also ordinary series and parallel connected architectures. Although the annual yield for the smart architecture is 79.5% of the yield of an ideal module, we show that the smart architecture outperforms a standard series connected module by 47%, and a parallel architecture by 13.4%.

  19. Characterization of cocoa production, income diversification and shade tree management along a climate gradient in Ghana

    Science.gov (United States)

    Jassogne, Laurence; Graefe, Sophie; Asare, Richard; Van Asten, Piet; Läderach, Peter; Vaast, Philippe

    2018-01-01

    Reduced climatic suitability due to climate change in cocoa growing regions of Ghana is expected in the coming decades. This threatens farmers’ livelihood and the cocoa sector. Climate change adaptation requires an improved understanding of existing cocoa production systems and farmers’ coping strategies. This study characterized current cocoa production, income diversification and shade tree management along a climate gradient within the cocoa belt of Ghana. The objectives were to 1) compare existing production and income diversification between dry, mid and wet climatic regions, and 2) identify shade trees in cocoa agroforestry systems and their distribution along the climatic gradient. Our results showed that current mean cocoa yield level of 288kg ha-1yr-1 in the dry region was significantly lower than in the mid and wet regions with mean yields of 712 and 849 kg ha-1 yr-1, respectively. In the dry region, farmers diversified their income sources with non-cocoa crops and off-farm activities while farmers at the mid and wet regions mainly depended on cocoa (over 80% of annual income). Two shade systems classified as medium and low shade cocoa agroforestry systems were identified across the studied regions. The medium shade system was more abundant in the dry region and associated to adaptation to marginal climatic conditions. The low shade system showed significantly higher yield in the wet region but no difference was observed between the mid and dry regions. This study highlights the need for optimum shade level recommendation to be climatic region specific. PMID:29659629

  20. Interior shadings for office indoor visual comfort in humid climate region

    Science.gov (United States)

    Dinapradipta, Asri; Sudarma, Erwin; Defiana, Ima; Erwindi, Collinthia

    2018-03-01

    As part of the fenestration system, the interior shadings have also a role to control the indoor environment to maintain indoor visual comfort. As the occupants have personal access to control these, their control behavior then, might enhance or even worsen indoor comfort performance. The controlling behavior might not only influence indoor comfort performance but can also indicate the success or failure of interior shading as a control device element. This paper is intended to report control behavior patterns, as represented by the variety of the slats’ openings of two types of interior shading i.e. Venetian and Vertical blinds and to analyze these on the concurrent impacts to indoor office building’s indoor illuminance and luminance distribution. The purpose of this research is to figure out the shading control patterns as well as to examine the effectiveness of these two types of interior shadings to control indoor visual environment. This study is a quantitative research using experimentation on the slats’ opening of two types of shadings at two identical office rooms. The research results suggested that both types of blinds seem unsuitable for gaining proper illumination values at work planes in humid tropics area. However, these shadings demonstrate good performance for luminance distribution except for that of the closed Venetian blinds.

  1. 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.

  2. 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.

  3. Response of Artemisia annua L. to shade and manure fertilizer application in lowland altitude

    Science.gov (United States)

    Permana, H. H.; Widyastuti, Y.; Samanhudi; Yunus, A.

    2018-03-01

    Artemisia is a plant producing artemisinin substance which is the main compound in the treatment of malaria. Artemisia comes from China, usually grows wild in native habitats in the plains with an altitude of 1,000-1,500 meters above the sea level. Artemisia development efforts in Indonesia hampered by limited land with the required altitude due to their competition with vegetable crops. Based on this reason, this research is conducted to observe the growth of artemisia planted in lowland with the help of shade and manure. This study aims to determine the level of shade and best manure on the growth of Artemisia. Research conducted at the Laboratory of the Faculty of Agriculture UNS Jumantono using nested design with two factors, shade as main factor and manure fertilizer as sub factor. The data analysis used F test with confidence level of 5%, if significant, then continued with DMRT (Duncan Multiple Range Test). The results showed the treatment of shade gave no difference in growth within 50% shade, 75% shade as well as without shade treatment. Goat manure fertilizer gave the highest result and able to increase plant height, number of branches, flower weight and root volume.

  4. Growth and bromatological characteristics of Brachiaria decumbens and Brachiaria ruziziensis under shading and nitrogen

    Directory of Open Access Journals (Sweden)

    Bruna Moscat Faria

    Full Text Available ABSTRACT This study aimed to evaluate the productive and qualitative characteristics of Brachiaria decumbens and Brachiaria ruziziensis subjected to three levels of artificial shading (0, 36 and 54% and four nitrogen (N doses (0; 50; 100 and 150 mg dm-3 soil, using completely randomized design with a factorial scheme 2 x 3 x 4, with three replications. The dry matter production (DMP, the number of tillers per pot, root weight and crude protein (CP and neutral detergent fiber (NDF contents were evaluated. Both grasses responded quadractly to N, but B. ruziziensis presented greater production under the two highest N doses. The tillers density increased with N dose and was reduced under shading. The root weight increased with N dose, linearly in the full sun and quadractly in the shade. The shading and N showed a positive influence on CP contents. For NDF content, was observed reduction with increase of N dose. The NDF content of B. decumbens increased with shading levels; for B. ruziziensis, the greatest value was observed under intermediate shading level. The N fertilization is an important strategy to improve DMP, tillers density and CP content, for both grasses. However, intense shading should be avoided, as it reduces tillering and root weight, which may threat pasture persistence.

  5. Application of a digital technique in evaluating the reliability of shade guides.

    Science.gov (United States)

    Cal, E; Sonugelen, M; Guneri, P; Kesercioglu, A; Kose, T

    2004-05-01

    There appears to be a need for a reliable method for quantification of tooth colour and analysis of shade. Therefore, the primary objective of this study was to show the applicability of graphic software in colour analysis and secondly to investigate the reliability of commercial shade guides produced by the same manufacturer, using this digital technique. After confirming the reliability and reproducibility of the digital method by using self-assessed coloured images, three shade guides of the same manufacturer were photographed in daylight and in studio environments with a digital camera and saved in tagged image file format (TIFF) format. Colour analysis of each photograph was performed using the Adobe Photoshop 4.0 graphic program. Luminosity, and red, green, blue (L and RGB) values of each shade tab of each shade guide were measured and the data were subjected to statistical analysis using the repeated measure Anova test. The L and RGB values of the images taken in daylight differed significantly from those of the images taken in studio environment (P < 0.05). In both environments, the luminosity and red values of the shade tabs were significantly different from each other (P < 0.05). It was concluded that, when the environmental conditions were kept constant, the Adobe Photoshop 4.0 colour analysis program could be used to analyse the colour of images. On the other hand, the results revealed that the accuracy of shade tabs widely being used in colour matching should be readdressed.

  6. Determining the energy performance of manually controlled solar shades: A stochastic model based co-simulation analysis

    International Nuclear Information System (INIS)

    Yao, Jian

    2014-01-01

    Highlights: • Driving factor for adjustment of manually controlled solar shades was determined. • A stochastic model for manual solar shades was constructed using Markov method. • Co-simulation with Energyplus was carried out in BCVTB. • External shading even manually controlled should be used prior to LOW-E windows. • Previous studies on manual solar shades may overestimate energy savings. - Abstract: Solar shading devices play a significant role in reducing building energy consumption and maintaining a comfortable indoor condition. In this paper, a typical office building with internal roller shades in hot summer and cold winter zone was selected to determine the driving factor of control behavior of manual solar shades. Solar radiation was determined as the major factor in driving solar shading adjustment based on field measurements and logit analysis and then a stochastic model for manually adjusted solar shades was constructed by using Markov method. This model was used in BCVTB for further co-simulation with Energyplus to determine the impact of the control behavior of solar shades on energy performance. The results show that manually adjusted solar shades, whatever located inside or outside, have a relatively high energy saving performance than clear-pane windows while only external shades perform better than regularly used LOW-E windows. Simulation also indicates that using an ideal assumption of solar shade adjustment as most studies do in building simulation may lead to an overestimation of energy saving by about 16–30%. There is a need to improve occupants’ actions on shades to more effectively respond to outdoor conditions in order to lower energy consumption, and this improvement can be easily achieved by using simple strategies as a guide to control manual solar shades

  7. Repressive Tolerance

    DEFF Research Database (Denmark)

    Pedersen, Morten Jarlbæk

    2017-01-01

    Consultation of organised interests and others when drafting laws is often seen as an important source of both input and output legitimacy. But whereas the input side of the equation stems from the very process of listening to societal actors, output legitimacy can only be strengthened if consult......Consultation of organised interests and others when drafting laws is often seen as an important source of both input and output legitimacy. But whereas the input side of the equation stems from the very process of listening to societal actors, output legitimacy can only be strengthened...... a substantial effect on the substance of laws – shows that there is a great difference in the amenability of different branches of government but that, in general, authorities do not listen much despite a very strong consultation institution and tradition. A suggestion for an explanation could be pointing...... 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...

  8. 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

  9. Effect of internal woven roller shade and glazing on the energy and daylighting performances of an office building in the cold climate of Shillong

    International Nuclear Information System (INIS)

    Singh, Ramkishore; Lazarus, I.J.; Kishore, V.V.N.

    2015-01-01

    Highlights: • We simulated a number of glazing and interior roller shade alternatives. • Office room has been simulated for three window-to-wall ratios in a cold climate. • Daylighting and energy performances have been assessed for each alternative. • Maximum energy savings have been estimated in the office with a 30% glazed area. • Energy saving decreases for larger glazed area and fabric transmittance. - Abstract: The energy and visual performances of the façades are defined by many parameters including façade size, properties of glazings and shadings, and their arrangements as well as control strategies. In this study, a number of combinations of internal woven roller shades and four double glazings have been proposed and assessed in integrated manner in order to improve the energy efficiency and visual comfort in new or existing office buildings. Office rooms facing south, east, north and west have been simulated for cold climate, by varying glazed areas and proposed glazing and shading alternatives. Results have been calculated, compared and analyzed in terms of the energy consumptions, energy saving potentials, daylight autonomy, useful daylight illuminance and discomfort glare free time, for each of the combinations. Simulation results show that the choice of glazing and shading alternatives can have substantial impact on energy and visual performances of the office space. Regardless of façade orientation, the maximum energy saving is achieved for a window-to-wall ratio (WWR) of 30%. Saving potential decreases significantly for larger glazed area and for each façade orientation. For all façade orientations and glazed areas (except for 30% WWR in the north wall), a bare low-e coated double glazing (U = 1.616 W/m"2 K, SHGC = 0.209, τ_v = 0.301) is found to be the most energy efficient choice. For 30% north glazing, the energy efficiency can be maximized with a different bare low-e coated double glazing (U = 1.628 W/m"2 K, SHGC = 0.370, τ_v = 0

  10. 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

  11. 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

  12. Effect of Shading on Physiological, Biochemical and Behaviour Changes in Crossbred Calves Under Hot Climatic Conditions

    International Nuclear Information System (INIS)

    Teama, F.E.I.; Gad, A.E.; El-Tarabany, A.A.

    2012-01-01

    The purpose of this study was to investigate the importance and the effect of shading and non-shading house on physiological changes, body weight (BW), average daily gain (ADG), total antioxidant and thyroid hormones in crossbred calves under hot conditions. Thirty six growing crossbred calves (Friesian x Baladi) aged 8-10 months were divided into two groups (each 18 calves); the first group was maintained in shaded house and the second in house without shade (climatic house). The period of study was 79 days during hot conditions. Performance variables (BW, ADG) were measured and the blood samples were collected to assess some biochemical parameters including antioxidants such as total antioxidant (TA), catalase (CAT), total protein, thyroid hormones (T3, T4) and immunoglobulin factor (IgG). Respiration rates and behaviour parameters (feeding, drinking, standing, lying and agonistic) were also measured during the study. The data indicated that the shaded calves had higher ADG (P<0.05) and final BW than non-shaded ones. Also, a significant improvement in total protein levels and globulins were recorded in shaded house calves as compared to non-shaded ones. The same result was obtained for T3 level whereas non-significant changes were observed for T4 level as well as the level of IgG at different times. The present data indicated that using shaded house will decrease the effect of heat stress on calves which will increase the animal performance through improving BW and ADG as well as some biochemical parameters in addition to T3 hormonal level.

  13. 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

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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)

  1. 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.

  2. 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

  3. Effect of shading intensity on morphological and color traits, and chemical components of new tea (Camellia sinensis L.) shoots under direct covering cultivation.

    Science.gov (United States)

    Sano, Tomohito; Horie, Hideki; Matsunaga, Akiko; Hirono, Yuhei

    2018-05-02

    Use of covering cultivation to shade tea (Camellia sinensis L.) trees to produce high-quality, high-priced green tea has recently increased in Japan. Knowledge of shading effects on morphological and color traits, and chemical components of new tea shoots is important for product quality and productivity. We assessed these traits of tea shoots and their relationships under covering cultivation of various radiation intensities. Leaf thickness, LMA (leaf mass per area), and leaf density of new tea leaves were smaller under covering culture than under open-field culture. SPAD values and chlorophyll contents were larger under covering culture than under open culture. The derived exponential equation for estimating chlorophyll contents from SPAD values was improved by considering leaf thickness. Covering culture decreased EC (epicatechin) and EGC (epigallocatechin) contents, and increased theanine and caffeine contents. Principal component analysis on shoot and leaf traits indicated that LMA, and chlorophyll, EC, and EGC contents were strongly associated with shading effects. Morphological and color traits, and chemical components of new tea shoots and leaves varied depending on radiation intensity, shoot growth, and cropping season. These findings are useful for covering cultivation with high quality and high productivity in tea gardens. This article is protected by copyright. All rights reserved.

  4. SRTM Colored Height and Shaded Relief: Corral de Piedra, Argentina

    Science.gov (United States)

    2001-01-01

    Volcanism and erosion are prominently seen in this view of the eastern flank of the Andes Mountains taken by Shuttle Radar Topography Mission (SRTM). The area is southeast of San Martin de Los Andes, Argentina. Eroded peaks up to 2,210-meter-high (7,260-foot) are seen on the west (left), but much of the scene consists of lava plateaus that slope gently eastward. These lava flows were most likely derived from volcanic sources in the high mountains. However, younger and more localized volcanic activity is evident in the topographic data as a cone surrounding oval-shaped flow near the center of the scene.The plateaus are extensively eroded by the Rio Limay (bottom of the image) and the Rio Collon Cura and its tributaries (upper half). The larger stream channels have reached a stable level and are now cutting broad valleys. Few terraces between the levels of the high plateaus and lower valleys (bottom center and upper right of the volcanic cone) indicate that stream erosion had once temporarily reached a higher stable level before eroding down to its current level. In general, depositional surfaces like lava flows are progressively younger with increasing elevation, while erosional surfaces are progressively younger with decreasing elevation.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear dark, as would be the case at noon at this latitude in the southern hemisphere. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red and magenta to white at the highest elevations.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging

  5. New Zealand, SRTM Shaded Relief and Colored Height

    Science.gov (United States)

    2004-01-01

    with the offset in the subduction zone pattern, vertical offsets (about 7 millimeters per year) are likewise consistent with the uplift of the Southern Alps. Two visualization methods were combined to produce this 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 additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C. Location: 33.5 to 48 degrees South latitude, 165 to 180 degrees East longitude Orientation: North toward the top, cylindrical projection Image Data: Shaded and colored SRTM elevation model Date Acquired: February 2000

  6. SRTM Colored Height and Shaded Relief: Pinon Canyon region, Colorado

    Science.gov (United States)

    2001-01-01

    Erosional features are prominent in this view of southern Colorado taken by the Shuttle Radar Topography Mission (SRTM). The area covers about 20,000 square kilometers and is located about 50 kilometers south of Pueblo, Colorado. The prominent mountains near the left edge of the image are the Spanish Peaks, remnants of a 20 million year old volcano. Rising 2,100 meters (7,000 ft) above the plains to the east, these igneous rock formations with intrusions of eroded sedimentary rock historically served as guiding landmarks for travelers on the Mountain Branch of the Santa Fe Trail.Near the center of the image is the Pinon Canyon Maneuver Site, a training area for soldiers of the U.S. Army from nearby Fort Carson. The site supports a diverse ecosystem with large numbers of big and small game, fisheries, non-game wildlife, forest, range land and mineral resources. It is bounded on the east by the dramatic topography of the Purgatoire River Canyon, a 100 meter (328 foot) deep scenic red canyon with flowing streams, sandstone formations, and exposed geologic processes.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction. Southern slopes appear bright and northern slopes appear dark. Color coding is directly related to topographic height, with blue and green at the lower elevations, rising through yellow and brown to white at the highest elevations.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 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 three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter

  7. Shaded Relief with Height as Color, Iturralde Structure, Bolivia

    Science.gov (United States)

    2002-01-01

    An 8-kilometer (5-mile) wide crater of possible impact origin is shown in this view of an isolated part of the Bolivian Amazon from the Shuttle Radar Topography Mission. The circular feature at the center-left of the image, known as the Iturralde Structure, is possibly the Earth's most recent 'big' impact event recording collision with a meteor or comet that might have occurred between 11,000 and 30,000 years ago.Although the structure was identified on satellite photographs in the mid-1980s, its location is so remote that it has only been visited by scientific investigators twice, most recently by a team from NASA's Goddard Space Flight Center in September 2002. Lying in an area of very low relief, the landform is a quasi-circular closed depression only about 20 meters (66 feet) in depth, with sharply defined sub-angular 'rim' materials. It resembles a 'cookie cutter' in that its appearance 'cuts' the heavily vegetated soft-sediments and pampas of this part of Bolivia. The SRTM data have provided investigators with the first topographic map of the site and will allow studies of its three-dimensional structure crucial to determining whether it actually is of impact origin.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction. North-facing slopes appear bright and south-facing slopes appear dark. Color coding is directly related to topographic height, with brown and green at the lower elevations, rising through yellow and brown to white at the highest elevations.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission aboard Space Shuttle Endeavour, launched on Feb. 11, 2000. The mission 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 Endeavour in 1994. The Shuttle Radar Topography Mission was

  8. Pando Province, Northern Bolivia, Shaded Relief and Colored Height

    Science.gov (United States)

    2003-01-01

    Pando Province, Bolivia, and adjacent parts of Brazil and Peru are seen in this visualization of Shuttle Radar Topography Mission (SRTM) elevation data covering part of the Amazon Basin. Most of this region is covered by tropical rainforest and is still largely unaltered by development, though new roads are providing increased access to the area, leading to changes in the landscape. SRTM data provide the first detailed three-dimensional look at the landforms of this region, and the Amazon Basin in its entirety, and will be particularly helpful in understanding the hydrologic patterns as environmental management becomes increasingly important.River drainage across this area flows generally east-northeast away from the nearby Andes Mountains. The most prominent river channels seen here are the Purus River in the northwest (upper left) and the Madre de Dios River, which crosses the south central (lower central) part of this view. The Beni and Mamore Rivers combine with the Madre de Dios in the eastern (right central) area to form the Madeira River, which flows northeast to eventually meet the Amazon River near Manaus.The Trans-Amazon Highway crosses the northern half of the scene, and subtle evidence of rainforest clear cutting, facilitated by this easy access, is apparent just north of the scene center, even at the low resolution of this display (740 m or 2428 feet). As seen here, clear cutting patterns in the rainforest typically show a pattern of parallel lines. SRTM mapped the shape of the Earths solid surface (not exclusively the ground surface), which includes to some degree land covers such as forests. Thus, SRTM data are capable of revealing deforestation patterns.For a smaller, annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site] (image size: 184k JPEG)A combination of visualization methods was used to produce this image, based on shading and color coding. A shade image was derived by computing

  9. Cuttlefish see shape from shading, fine-tuning coloration in response to pictorial depth cues and directional illumination.

    Science.gov (United States)

    Zylinski, Sarah; Osorio, D; Johnsen, Sonke

    2016-03-16

    Humans use shading as a cue to three-dimensional form by combining low-level information about light intensity with high-level knowledge about objects and the environment. Here, we examine how cuttlefish Sepia officinalis respond to light and shadow to shade the white square (WS) feature in their body pattern. Cuttlefish display the WS in the presence of pebble-like objects, and they can shade it to render the appearance of surface curvature to a human observer, which might benefit camouflage. Here we test how they colour the WS on visual backgrounds containing two-dimensional circular stimuli, some of which were shaded to suggest surface curvature, whereas others were uniformly coloured or divided into dark and light semicircles. WS shading, measured by lateral asymmetry, was greatest when the animal rested on a background of shaded circles and three-dimensional hemispheres, and less on plain white circles or black/white semicircles. In addition, shading was enhanced when light fell from the lighter side of the shaded stimulus, as expected for real convex surfaces. Thus, the cuttlefish acts as if it perceives surface curvature from shading, and takes account of the direction of illumination. However, the direction of WS shading is insensitive to the directions of background shading and illumination; instead the cuttlefish tend to turn to face the light source. © 2016 The Author(s).

  10. San Gabriel Mountains, California, Shaded relief, color as height

    Science.gov (United States)

    2000-01-01

    This topographic image shows the relationship of the urban area of Pasadena, California to the natural contours of the land. The image includes the alluvial plain on which Pasadena and the Jet Propulsion Laboratory sit, and the steep range of the San Gabriel Mountains. The mountain front and the arcuate valley running from upper left to the lower right are active fault zones, along which the mountains are rising. The chaparral-covered slopes above Pasadena are also a prime area for wildfires and mudslides. Hazards from earthquakes, floods and fires are intimately related to the topography in this area. Topographic data and other remote sensing images provide valuable information for assessing and mitigating the natural hazards for cities along the front of active mountain ranges.This shaded relief image was generated using topographic data from the Shuttle Radar Topography Mission. A computer-generated artificial light source illuminates the elevation data to produce a pattern of light and shadows. Slopes facing the light appear bright, while those facing away are shaded. On flatter surfaces, the pattern of light and shadows can reveal subtle features in the terrain. Colors show the elevation as measured by SRTM. Colors range from blue at the lowest elevations to white at the highest elevations. This image contains about 2300 meters (7500 feet) of total relief. White speckles on the face of some of the mountains are holes in the data caused by steep terrain. These will be filled using coverage from an intersecting pass.The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses 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. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna

  11. Shaded Relief with Height as Color, Mount Meru, Tanzania

    Science.gov (United States)

    2002-01-01

    Mount Meru is an active volcano located just 70 kilometers (44 miles) west of Mount Kilimanjaro. It reaches 4,566 meters (14,978 feet) in height but has lost much of its bulk due to an eastward volcanic blast sometime in its distant past, perhaps similar to the eruption of Mount Saint Helens in Washington State in 1980. Mount Meru most recently had a minor eruption about a century ago. The several small cones and craters seen in the vicinity probably reflect numerous episodes of volcanic activity. Mount Meru is the topographic centerpiece of Arusha National Park. Its fertile slopes rise above the surrounding savanna and support a forest that hosts diverse wildlife, including nearly 400 species of birds, and also monkeys and leopards.Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear dark, as would be the case at noon at this latitude in June. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, to blue and white at the highest elevations.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.S. Department of Defense and the German and Italian space

  12. Heat tolerance in Field Grown Tomatoes (Lycopersicon esculentum Mill.) under Semi Arid Conditions of West Africa

    DEFF Research Database (Denmark)

    Kugblenu, Y O; Oppong Danso, E; Ofori, K

    2013-01-01

    One major reason for extremely low production of tomato in Ghana is that the length of the growing season last only for a few months due to the high temperature influx during the remaining months. The temperatures recorded during these months are above the optimum for tomato flowering and fruiting...... and this consequently affects yield. To solve this problem a number management practices may be undertaken such has growing heat tolerant tomato varieties or providing shade to mitigate the devastating effect of high temperatures. Therefore the present study was conducted outside the normal growing season from June...... to October, which has a mean temperature of 23°C. Heat tolerant tomato cultivars were grown from April to July with a mean temperature of 25°C to evaluate their performance under these conditions and to assess the effect of shading on the production of one of the genotypes. Fruiting percentage...

  13. 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.

  14. Influence of artificial accelerated aging on the color stability and opacity of composites of different shades.

    Science.gov (United States)

    Mundim, F M; Da Fonseca Roberti Garcia, L; Silva Sousa, A B; Cruvinel, D R; De Carvalho Panzeri Pires-De-Souza, F

    2010-10-01

    The aim of this study was to evaluate the influence of artificial accelerated aging on the color stability and opacity of composites of different shades. Four composites for direct use (Heliomolar, 4 Seasons, Tetric EvoCeram; QuiXfil) and one for indirect use (SR Adoro) in two shades were used: light (A2) and dark (C3 for direct, and D4 for indirect composite). QuiXfil was obtained in Universal shade. A Teflon matrix (12 X 2 mm) was used to obtain 54 specimens (N=6), which were submitted to color and opacity analysis (Spectrophotometer PCB 6807, Byk Gardner) before and after artificial accelerated aging for 384 hours. After the statistical analysis (2-way ANOVA - Bonferroni - PArtificial accelerated aging interfered in the optical properties assessed; however, the alterations seemed to be more related to the composites composition than to their shade.

  15. 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.

  16. Assessment of microclimate conditions under artificial shades in a ginseng field

    Directory of Open Access Journals (Sweden)

    Kyu Jong Lee

    2016-01-01

    Conclusion: Weather measurements outside the shade and LWD estimates derived from these measurements would be useful as inputs for decision support systems to predict ginseng growth and disease development.

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

    African Journals Online (AJOL)

    Keywords: Behavioural pattern , dairy cows, heat stress, shade. * Author to whom ... The negative effect of high temperatures, solar radiation, relative humidity and ..... Cattle do nct exhibit true sleep as in humans, except for very short periods.

  18. Multiple Solutions for Reconfiguration to Address Partial Shading Losses in Solar Photovoltaic Arrays

    Science.gov (United States)

    Sharma, Nikesh; Pareek, Smita; Chaturvedi, Nitin; Dahiya, Ratna

    2018-03-01

    Solar photovoltaic (SPV) systems are steadily rising and considered as the best alternatives to meet the rising demand of energy. In developing countries like India, SPV’s contribution being a clean energy is the most favourable. However, experiences have shown that produced power of these systems is usually affected due to day, night, seasonal variations, insolation, partial shading conditions etc. Among these parameters, partial shading causes a huge reduction in output power of PV systems. This results in lack of confidence for this technology among users. Thus, it is important and a major challenge in PV systems to minimize the effect of partial shading on their energy production. The work in this paper aims to propose solutions for reconfiguration of solar photovoltaic arrays in order to reduce partial shading losses and thus to enhance power generation.

  19. Comparative Analysis of Maximum Power Point Tracking Controllers under Partial Shaded Conditions in a Photovoltaic System

    Directory of Open Access Journals (Sweden)

    R. Ramaprabha

    2015-06-01

    Full Text Available Mismatching effects due to partial shaded conditions are the major drawbacks existing in today’s photovoltaic (PV systems. These mismatch effects are greatly reduced in distributed PV system architecture where each panel is effectively decoupled from its neighboring panel. To obtain the optimal operation of the PV panels, maximum power point tracking (MPPT techniques are used. In partial shaded conditions, detecting the maximum operating point is difficult as the characteristic curves are complex with multiple peaks. In this paper, a neural network control technique is employed for MPPT. Detailed analyses were carried out on MPPT controllers in centralized and distributed architecture under partial shaded environments. The efficiency of the MPPT controllers and the effectiveness of the proposed control technique under partial shaded environments was examined using MATLAB software. The results were validated through experimentation.

  20. Duration and intensity of shade differentially affects mycorrhizal growth- and phosphorus uptake responses of Medicago truncatula

    Czech Academy of Sciences Publication Activity Database

    Konvalinková, T.; Püschel, David; Janoušková, Martina; Gryndler, M.; Jansa, J.

    2015-01-01

    Roč. 6, FEB 13 (2015), s. 1-11 ISSN 1664-462X Institutional support: RVO:67985939 Keywords : arbuscular mycorrhizal symbiosis * light intensity * shading duration Subject RIV: EE - Microbiology, Virology Impact factor: 4.495, year: 2015

  1. Shade tree diversity enhances coffee production and quality in agroforestry systems in the Western Ghats

    NARCIS (Netherlands)

    Nesper, Maike; Kueffer, Christoph; Krishnan, Smitha; Kushalappa, Cheppudira G.; Ghazoul, Jaboury

    2017-01-01

    Intensification of multispecies coffee agroforests reduces shade tree diversity with implications for tropical biodiversity. We investigated how tree biodiversity and its effects on coffee production and quality changes along a gradient of intensification (from diverse multispecies to Grevillea

  2. Comparison of shade matching by visual observation and an intraoral dental colorimeter.

    Science.gov (United States)

    Li, Q; Wang, Y N

    2007-11-01

    The purpose of this study was to compare the applicability of two shade-matching approaches: Vintage Halo shade guide (visual method) and Shofu ShadeEye NCC colorimeter (instrumental method). Twenty participants' maxillary left central incisors were evaluated. Corresponding metal ceramic crowns were fabricated with each shade-matching approach. The colour distributions (L*, a* and b*) of the middle third region of each tooth and corresponding metal ceramic crowns were spectrophotometrically assessed. The colour difference (DeltaE) and colour distributions (DeltaL*, Deltaa* and Deltab*) between the tooth and the corresponding crowns were calculated. We found that the colour differences of both groups fell within the clinical unacceptable range (DeltaE > 2.75). Regarding DeltaE and the three colour distributions, no significant difference was found, expect for a* (P colorimeter nor the visual approach. However, the colorimeter can achieve better results within easy matching cases.

  3. [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.

  4. Is shade for horses a comfort resource or a minimum requirement?

    Science.gov (United States)

    Holcomb, K E

    2017-09-01

    Shade or shelter as protection from extremes of weather is required for horses at agricultural research and teaching facilities and is recommended or required by many states, professional organizations, and industry groups. The focus of this paper is the recent research on the responses of horses to hot, sunny weather, which has begun to provide scientific evidence that characterizes how and when shade is used and any benefits shade confers on horses. These behavioral and physiological findings support provision of shade as a resource for thermal comfort and the expression of normal behavior that should be included as a standard of best care practices for healthy adult horses living in the environmental conditions reviewed, rather than an absolute minimum care requirement. Additional research is required for horses living under other environmental conditions, for very young or old horses, horses in very poor body condition, or those with compromised health to determine if their responses to hot, sunny weather differ from those presented here.

  5. Photosynthetic light response of the C4 grasses Brachiaria brizantha and B. humidicola under shade

    Directory of Open Access Journals (Sweden)

    Dias-Filho Moacyr Bernardino

    2002-01-01

    Full Text Available Forage grasses in tropical pastures can be subjected to considerable diurnal and seasonal reductions in available light. To evaluate the physiological behavior of the tropical forage grasses Brachiaria brizantha cv. Marandu and B. humidicola to low light, the photosynthetic light response and chlorophyll contents of these species were compared for plants grown outdoors, on natural soil, in pots, in full sunlight and those shaded to 30 % of full sunlight, over a 30-day period. Both species showed the ability to adjust their photosynthetic behavior in response to shade. Photosynthetic capacity and light compensation point were lower for shade plants of both species, while apparent quantum yield was unaffected by the light regime. Dark respiration and chlorophyll a:b ratio were significantly reduced by shading only in B. humidicola. B. humidicola could be relatively more adapted to succeed, at least temporarily, in light-limited environments.

  6. 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 ... balance of an animal but does not affect air temperature or .... temperature above this temperature limits reproductive.

  7. Effects of shade and drought stress on soybean hormones and yield ...

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... hormone concentrations, main-stem and branch yield response to the combination of shade and drought were studied ... yield primarily by reducing branch growth and branch seed yield per ..... deficit soybean. Yield decrease ...

  8. 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.

  9. 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.

  10. Response of lentil (Lens culinaris Medik.) to artificial shading during the reproductive stage

    International Nuclear Information System (INIS)

    Peñaloza H, Enrique; Díaz S, Jorge

    1997-01-01

    Lentil production in southern Chile is subject to significant seasonal fluctuations in solar radiation received during the reproductive stage, with an average variation ranging from 300 to 650 g cal cm -2 day -1 . to quantify the effect of reducing incident light on crop performance, artifical shading experiments were conducted with 80% light reduction during different periods spanning the reprodcutive stage, as well as various degrees of shading (0, 20, 35, 50 and 80%) throughout. shading was achieved by using a black polypropylene net placed at 0.8 m above soil surface. The experiments were carried out during the 1991/92, 1992/93 and 1993/94 cropping seasons at the Centro Regional de Investigación Carillanca, INIA (38°41' S, 72°25' W). The effect of 80% shading on seed yield was dependent upon the period at which the treatment was imposed. Seed yield reduction was higher when shading occurred during the growth stages R--R5, accounting 35, 48 and 59% yield losses for the 1991/92, 1992/93 and 1993/94 seasons, respectively. No significant diffreences were detected between R1-R3 and R5-R8 periods, with seed yield losses averaging 39 (1991/92), 10 (1992/93) and 25% (1993/94). Variations in seed yield due to shading were explained mainly by a reduction of total pods m -2 and an increase in empty (flat) pods (R3-R5), and a reduction on the average seed weight (R5-R8). As expected, the higher losses occurred on treatments exposed to two (R1-R5, R3-R8) or three (R1-R8) periods of shading. Grain yield under different degrees of shading was significantly reduced, with responses fitted to the functions Y = 2.020-32.5s + 0.18s 2 (1992/93) and Y = 2.172-25.6s-0.04s 2 (1993/94). Reduction on seed yield was associated to a decrease in total pods m -2 and average seed weight, whereas empty pods increased significantly only at near 80% shading. These results point at R3-R5 as the most sensible growth stage under 80% shading and demonstrate the sensitiveness of lentil

  11. 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.

  12. 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.

  13. 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.

  14. Photosynthesis and chlorophyll fluorescence reaction to different shade stresses of weak light sensitive maize

    International Nuclear Information System (INIS)

    Wang, J.; Li, F.; Shi, Z.; Huang, H.; Jia, S.

    2017-01-01

    A split-plot experimental study was conducted to evaluate the effect of different shade stresses on photosynthesis and chlorophyll fluorescence of maize leaves.The experiment was designed on the south farm of Special Corn Institute, Shenyang Agricultural University, China.Data was collected from the day maize tasseled (Jul. 21) to the beginning of grouting (Aug.12 ) under 18%, 28%, 38%, 60%, and 75% shade stress to determine indexes such as photosynthesis and chlorophyll fluorescence after 15 days of shade treatment. Pairs of near-isogenic lines (NILs) of Shennong 98A (a barren stalk inbred line) and Shennong 98B (an un-barren stalk inbred line) were used as experimental materials to further reveal photosynthetic mechanisms of weak light sensitive maize when exposed to weak light conditions. Thus, a foundation was established for high density-resistant (shade resistant) corn breeding,while identifying weak light sensitive varieties. After shading treatment, chlorophyll a and total chlorophyll content of both varieties increased, chlorophyll b content first increased, followed by a decrease, while the net photosynthetic rate and stomatal conductance showed a gradually decreasing trend. The changing trends of photochemical quenching coefficient(qp) and effective quantum yield of PSII photochemistry (FPSII)were similar, FPSII and qP increased significantly as shading stress increased from 18% to 38%;however, FPSII and qP declined significantly under 60% and 75% shading stresses. The changing trend of NPQ was opposite to FPSII and qP. A comparison of both inbred lines showed that photosynthesis and chlorophyll fluorescence characteristics of Shennong 98B were superior to Shennong 98A. This study revealed the relationships between weak light sensitive lines and shade intensities by comparing differences in photosynthesis and chlorophyll fluorescence parameters. (author)

  15. Is shade beneficial for mediterranean shrubs experiencing periods of extreme drought and late-winter frosts?

    Science.gov (United States)

    Valladares, Fernando; Zaragoza-Castells, Joana; Sánchez-Gómez, David; Matesanz, Silvia; Alonso, Beatriz; Portsmuth, Angelika; Delgado, Antonio; Atkin, Owen K

    2008-12-01

    Plants are naturally exposed to multiple, frequently interactive stress factors, most of which are becoming more severe due to global change. Established plants have been reported to facilitate the establishment of juvenile plants, but net effects of plant-plant interactions are difficult to assess due to complex interactions among environmental factors. An investigation was carried out in order to determine how two dominant evergreen shrubs (Quercus ilex and Arctostaphylos uva-ursi) co-occurring in continental, Mediterranean habitats respond to multiple abiotic stresses and whether the shaded understorey conditions ameliorate the negative effects of drought and winter frosts on the physiology of leaves. Microclimate and ecophysiology of sun and shade plants were studied at a continental plateau in central Spain during 2004-2005, with 2005 being one of the driest and hottest years on record; several late-winter frosts also occurred in 2005. Daytime air temperature and vapour pressure deficit were lower in the shade than in the sun, but soil moisture was also lower in the shade during the spring and summer of 2005, and night-time temperatures were higher in the shade. Water potential, photochemical efficiency, light-saturated photosynthesis, stomatal conductance and leaf 13C composition differed between sun and shade individuals throughout the seasons, but differences were species specific. Shade was beneficial for leaf-level physiology in Q. ilex during winter, detrimental during spring for both species, and of little consequence in summer. The results suggest that beneficial effects of shade can be eclipsed by reduced soil moisture during dry years, which are expected to be more frequent in the most likely climate change scenarios for the Mediterranean region.

  16. 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...

  17. Pasture shade and farm management effects on cow productivity in the tropics

    OpenAIRE

    Ainsworth, Justin A.W.; Moe, Stein R.; Skarpe, Christina

    2012-01-01

    This is the postprint version of the article. The published article can be located at the publisher's webpage Shade, provided by trees within pastures, can affect cattle productivity through mitigating heat stress and by altering understorey pasture growth and cattle behaviour. Models for daily milk yield and body condition were used to evaluate the effect of pasture shade on dual purpose cow productivity within a silvopastoral system in a dry tropical province of Nicaragua. Daily milk yie...

  18. 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.

  19. 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.

  20. Power Enhancement of Partial Shaded PV Array by Optimizing the Electrical Connection of Module

    Directory of Open Access Journals (Sweden)

    Wang Mengyao

    2015-01-01

    Full Text Available The maximum output power (Pmax generated from photovoltaic (PV array will be apparently reduced if the array is partially shaded. In order to enhance Pmax generated from partial shaded PV array, several interconnection schemes of array are proposed. Among these schemes, the totally cross tied (TCT scheme and the recently proposed static scheme are widely discussed. It was reported that Pmax produced with static scheme is equal to the TCT scheme even under worst conditions. However, in these simulations the illumination of every single module is assumed to be uniform, but in urban environments the illumination of modules on the edge of shadow is more likely to be non-uniform. In this paper, first, a comprehensive circuit-level simulation, which is implemented in PSpice, has been done to investigate performance of PV array with both TCT scheme and static scheme under different partial shading conditions. And the results show that Pmax generated from static scheme is higher than that form TCT scheme if the illumination of every single module is uniform, however if some modules are partially shaded, the Pmax with static scheme is more likely less than that with TCT scheme. Then, the electrical connection of a module is improved for the purpose of enhancing Pmax under partial shading conditions in which some modules in the array are partially shaded. And the simulation results show that Pmax is apparently increased by employing the improved modules.

  1. 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

  2. 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

  3. 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.

  4. A Pareto-based multi-objective optimization algorithm to design energy-efficient shading devices

    International Nuclear Information System (INIS)

    Khoroshiltseva, Marina; Slanzi, Debora; Poli, Irene

    2016-01-01

    Highlights: • We present a multi-objective optimization algorithm for shading design. • We combine Harmony search and Pareto-based procedures. • Thermal and daylighting performances of external shading were considered. • We applied the optimization process to a residential social housing in Madrid. - Abstract: In this paper we address the problem of designing new energy-efficient static daylight devices that will surround the external windows of a residential building in Madrid. Shading devices can in fact largely influence solar gains in a building and improve thermal and lighting comforts by selectively intercepting the solar radiation and by reducing the undesirable glare. A proper shading device can therefore significantly increase the thermal performance of a building by reducing its energy demand in different climate conditions. In order to identify the set of optimal shading devices that allow a low energy consumption of the dwelling while maintaining high levels of thermal and lighting comfort for the inhabitants we derive a multi-objective optimization methodology based on Harmony Search and Pareto front approaches. The results show that the multi-objective approach here proposed is an effective procedure in designing energy efficient shading devices when a large set of conflicting objectives characterizes the performance of the proposed solutions.

  5. The effect of partial shading on dye-sensitized solar cell module characteristics

    International Nuclear Information System (INIS)

    Pan, Bin; Weng, Jian; Chen, Shuanghong; Huang, Yang; Dai, Songyuan

    2014-01-01

    The dye-sensitized solar cell (DSC) is a kind of novel solar cell with prospects for building integrated photovoltaic applications. In some situations, a DSC module may work under partial shading conditions, and subsequently the module temperature and I–V characteristics change. In this work, the effect of partial shading on DSC module characteristics is experimentally studied and the temperature and electric output of the partially shaded DSC module are measured. The variations of module temperature and output performance are analyzed under short circuit conditions and a normal operating mode of charging battery. Furthermore, the stability of the partially shaded DSC module is also evaluated. It is found that the temperature rise of the DSC module caused by partial shading is slower and much smaller than the silicon solar cell, and the characteristics of the single DSC that suffered from short-term shading remain stable. For a DSC module operating in charging mode, the maximum power point and working point change when a shadow appears. (paper)

  6. Induced tolerance from a sublethal insecticide leads to cross-tolerance to other insecticides.

    Science.gov (United States)

    Hua, Jessica; Jones, Devin K; Relyea, Rick A

    2014-04-01

    As global pesticide use increases, the ability to rapidly respond to pesticides by increasing tolerance has important implications for the persistence of nontarget organisms. A recent study of larval amphibians discovered that increased tolerance can be induced by an early exposure to low concentrations of a pesticide. Since natural systems are often exposed to a variety of pesticides that vary in mode of action, we need to know whether the induction of increased tolerance to one pesticide confers increased tolerance to other pesticides. Using larval wood frogs (Lithobates sylvaticus), we investigated whether induction of increased tolerance to the insecticide carbaryl (AChE-inhibitor) can induce increased tolerance to other insecticides that have the same mode of action (chlorpyrifos, malathion) or a different mode of action (Na(+)channel-interfering insecticides; permethrin, cypermethrin). We found that embryonic exposure to sublethal concentrations of carbaryl induced higher tolerance to carbaryl and increased cross-tolerance to malathion and cypermethrin but not to chlorpyrifos or permethrin. In one case, the embryonic exposure to carbaryl induced tolerance in a nonlinear pattern (hormesis). These results demonstrate that that the newly discovered phenomenon of induced tolerance also provides induced cross-tolerance that is not restricted to pesticides with the same mode of action.

  7. 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.

  8. 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

  9. Fast shading correction for cone beam CT in radiation therapy via sparse sampling on planning CT.

    Science.gov (United States)

    Shi, Linxi; Tsui, Tiffany; Wei, Jikun; Zhu, Lei

    2017-05-01

    The image quality of cone beam computed tomography (CBCT) is limited by severe shading artifacts, hindering its quantitative applications in radiation therapy. In this work, we propose an image-domain shading correction method using planning CT (pCT) as prior information which is highly adaptive to clinical environment. We propose to perform shading correction via sparse sampling on pCT. The method starts with a coarse mapping between the first-pass CBCT images obtained from the Varian TrueBeam system and the pCT. The scatter correction method embedded in the Varian commercial software removes some image errors but the CBCT images still contain severe shading artifacts. The difference images between the mapped pCT and the CBCT are considered as shading errors, but only sparse shading samples are selected for correction using empirical constraints to avoid carrying over false information from pCT. A Fourier-Transform-based technique, referred to as local filtration, is proposed to efficiently process the sparse data for effective shading correction. The performance of the proposed method is evaluated on one anthropomorphic pelvis phantom and 17 patients, who were scheduled for radiation therapy. (The codes of the proposed method and sample data can be downloaded from https://sites.google.com/view/linxicbct) RESULTS: The proposed shading correction substantially improves the CBCT image quality on both the phantom and the patients to a level close to that of the pCT images. On the phantom, the spatial nonuniformity (SNU) difference between CBCT and pCT is reduced from 74 to 1 HU. The root of mean square difference of SNU between CBCT and pCT is reduced from 83 to 10 HU on the pelvis patients, and from 101 to 12 HU on the thorax patients. The robustness of the proposed shading correction is fully investigated with simulated registration errors between CBCT and pCT on the phantom and mis-registration on patients. The sparse sampling scheme of our method successfully

  10. 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

  11. Climate-change refugia: shading reef corals by turbidity.

    Science.gov (United States)

    Cacciapaglia, Chris; van Woesik, Robert

    2016-03-01

    Coral reefs have recently experienced an unprecedented decline as the world's oceans continue to warm. Yet global climate models reveal a heterogeneously warming ocean, which has initiated a search for refuges, where corals may survive in the near future. We hypothesized that some turbid nearshore environments may act as climate-change refuges, shading corals from the harmful interaction between high sea-surface temperatures and high irradiance. We took a hierarchical Bayesian approach to determine the expected distribution of 12 coral species in the Indian and Pacific Oceans, between the latitudes 37°N and 37°S, under representative concentration pathway 8.5 (W m(-2) ) by 2100. The turbid nearshore refuges identified in this study were located between latitudes 20-30°N and 15-25°S, where there was a strong coupling between turbidity and tidal fluctuations. Our model predicts that turbidity will mitigate high temperature bleaching for 9% of shallow reef habitat (to 30 m depth) - habitat that was previously considered inhospitable under ocean warming. Our model also predicted that turbidity will protect some coral species more than others from climate-change-associated thermal stress. We also identified locations where consistently high turbidity will likely reduce irradiance to turbid nearshore refuges identified in this study, particularly in the northwestern Hawaiian Islands, the northern Philippines, the Ryukyu Islands (Japan), eastern Vietnam, western and eastern Australia, New Caledonia, the northern Red Sea, and the Arabian Gulf, should become part of a judicious global strategy for reef-coral persistence under climate change. © 2015 John Wiley & Sons Ltd.

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

    Directory of Open Access Journals (Sweden)

    William Domeris

    2016-08-01

    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

  13. Correlation between grain orientation and the shade of color etching

    International Nuclear Information System (INIS)

    Szabo, Peter J.; Kardos, I.

    2010-01-01

    Color etching is an extremely effective metallographic technique not only for making grains well visible, but also for making them distinguishable for automated image analyzers. During color etching, a thin film is formed on the surface of the specimen. The thickness of this layer is in the order of magnitude of the visible light and since both the metal-film boundary and the film surface reflect light, an interference occurs. A wavelength-component of the white line is eliminated and its complementary color will be seen on the surface. As the thickness changes, the colors also change grain by grain. The thickness of the film is dependent on several factors, mostly on the type of the phase. However, different color shades can be observed on the surfaces of single phase materials, which phenomenon is caused by the different crystallographic orientations of the grains. This paper shows a combined color etching electron backscatter diffraction (EBSD) investigation of cast iron. An area of the surface of a gray cast iron specimen was etched. Colors were characterized by their luminescence and their red, green and blue intensity. An EBSD orientation map was taken from the same area and the orientations of the individual grains were determined. Results showed that a strong correlation was found between the luminescence and the R, G, B intensity of the color and the angle between the specimen normal and the direction, while such correlation was not observed between the color parameters and the and directions, respectively. This indicates that film thickness is sensitive to the direction of the crystal.

  14. Utilising shade to optimize UV exposure for vitamin D

    Science.gov (United States)

    Turnbull, D. J.; Parisi, A. V.

    2008-06-01

    Numerous studies have stated that humans need to utilise full sun radiation, at certain times of the day, to assist the body in synthesising the required levels of vitamin D3. The time needed to be spent in the full sun depends on a number of factors, for example, age, skin type, latitude, solar zenith angle. Current Australian guidelines suggest exposure to approximately 1/6 to 1/3 of a minimum erythemal dose (MED), depending on age, would be appropriate to provide adequate vitamin D3 levels. The aim of the study was to determine the exposure times to diffuse solar UV to receive exposures of 1/6 and 1/3 MED for a changing solar zenith angle in order to assess the possible role that diffuse UV (scattered radiation) may play in vitamin D3 effective UV exposures (UVD3). Diffuse and global erythemal UV measurements were conducted at five minute intervals over a twelve month period for a solar zenith angle range of 4° to 80° at a latitude of 27.6° S. For a diffuse UV exposure of 1/3 MED, solar zenith angles smaller than approximately 50° can be utilised for exposure times of less than 10 min. Spectral measurements showed that, for a solar zenith angle of 40°, the UVA (315-400 nm) in the diffuse component of the solar UV is reduced by approximately 62% compared to the UVA in the global UV, whereas UVD3 wavelengths are only reduced by approximately 43%. At certain latitudes, diffuse UV under shade may play an important role in providing the human body with adequate levels of UVD3 (290-315 nm) radiation without experiencing the high levels of UVA observed in full sun.

  15. Shaded Relief with Height as Color, North America

    Science.gov (United States)

    2003-01-01

    Manitoba to North Dakota and Minnesota, huge striations clearly show the flow pattern of the glaciers. And southwest of Lakes Michigan, Huron, and Erie, arcing ridges of sediment, called terminal moraines, show where glaciers dumped sediment at their melting ends.In eastern Canada, New York, and New England, the terrain has been scoured by glaciers, and eroded by streams, particularly along fractures in the bedrock. In Labrador and Quebec, the Mistastin, Manicougan, and Clearwater Lakes meteor impact craters can also be seen. Further south, narrow curving ridges of upturned and eroded layered rocks form most of the Appalachian Mountains. In contrast, around the Caribbean Sea region (Yucatan, Florida, and the Bahamas), flat-lying, stable limestone platforms are common, while the most eastern islands of the Caribbean include active volcanoes along another convergence zone of tectonic plates.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 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

  16. 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.

  17. Influence of shading on ornamental and physiological characteristics during flower development of groundcover rose (Rosa hybrida L.)

    Science.gov (United States)

    Hou, Wei; Luo, Ya; Wang, Xiaorong; Chen, Qing; Sun, Bo; Wang, Yan; Liu, Zejing; Tang, Haoru; Zhang, Yong

    2018-04-01

    The objective of the present investigation was to study the effect of shading on flower quality during flower development and photosynthetic capacity of groundcover rose (Rosa hybrida L.). The results showed that shade significantly increased flower diameter, levels of soluble protein and soluble sugar, total carotenoids content and superoxide dismutase (SOD) activity, while contents of malondialdehyde (MDA) and total anthocyanins in shaded flowers were significantly decreased as compared to sun-exposed flowers. However, no significant changes were observed in petal color parameters L*, a*, b* and C* between sun exposure and shade treatment plants at each flower developmental stage. Therefore, groundcover rose seemed to have the capacity to shade condition through auto-regulation. These results could provide us with a theoretical basis for further application of groundcover rose in the greening of urban spaces and an understanding of the mechanisms behind the changes induced by shade.

  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. 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.

  20. 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.

  1. 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.

  2. Teaching Tolerance? Associational Diversity and Tolerance Formation

    DEFF Research Database (Denmark)

    Rapp, Carolin; Freitag, Markus

    2015-01-01

    , a closer look is taken at how associational diversity relates to the formation of tolerance and the importance of associations as schools of tolerance are evaluated. The main theoretical argument follows contact theory, wherein regular and enduring contact in diverse settings reduces prejudice and thereby...

  3. VIDEO ANIMASI 3D PENGENALAN RUMAH ADAT DAN ALAT MUSIK KEPRI DENGAN MENGUNAKAN TEKNIK RENDER CEL-SHADING

    OpenAIRE

    Jianfranco Irfian Asnawi; Afdhol Dzikri

    2016-01-01

    Animasi ini berjudul "video animasi 3D rumah adat dan alat musik Kepulauan Riau dengan menggunakan teknik render cel-shading" merupakan video yang bertujuan memperkenalkan alat-alat musik yang berasal dari kepulauan riau, Animasi ini akan diterapkan dengan menggunakan teknik render cel-shading. Cel-shading adalah teknik render yang menampilkan grafik 3D yang menyerupai gambar tangan, seperti gambar komik dan kartun. Teknik ini juga sudah di terapkan dalam game 3D yang ternyata menarik banyak ...

  4. Application of thermography for monitoring stomatal conductance of Coffea arabica under different shading systems.

    Science.gov (United States)

    Craparo, A C W; Steppe, K; Van Asten, P J A; Läderach, P; Jassogne, L T P; Grab, S W

    2017-12-31

    Stomatal regulation is a key process in the physiology of Coffea arabica (C. arabica). Intrinsically linked to photosynthesis and water relations, it provides insights into the plant's adaptive capacity, survival and growth. The ability to rapidly quantify this parameter for C. arabica under different agroecological systems would be an indispensable tool. Using a Flir E6 MIR Camera, an index that is equivalent to stomatal conductance (I g ) was compared with stomatal conductance measurements (g s ) in a mature coffee plantation. In order to account for varying meteorological conditions between days, the methods were also compared under stable meteorological conditions in a laboratory and I g was also converted to absolute stomatal conductance values (g 1 ). In contrast to typical plant-thermography methods which measure indices once per day over an extended time period, we used high resolution hourly measurements over daily time series with 9 sun and 9 shade replicates. Eight daily time series showed a strong correlation between methods, while the remaining 10 were not significant. Including several other meteorological parameters in the calculation of g 1 did not contribute to any stronger correlation between methods. Total pooled data (combined daily series) resulted in a correlation of ρ=0.66 (P≤2.2e-16), indicating that our approach is particularly useful for situations where absolute values of stomatal conductance are not required, such as for comparative purposes, screening or trend analysis. We use the findings to advance the protocol for a more accurate methodology which may assist in quantifying advantageous microenvironment designs for coffee, considering the current and future climates of coffee growing regions. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  5. Tolerance of snakes to hypergravity

    Science.gov (United States)

    Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.

    1996-01-01

    Sensitivity of carotid blood flow to increased gravitational force acting in the head-to-tail direction(+Gz) was studied in diverse species of snakes hypothesized to show adaptive variation of response. Tolerance to increased gravity was measured red as the maximum graded acceleration force at which carotid blood flow ceased and was shown to vary according to gravitational adaptation of species defined by their ecology and behavior. Multiple regression analysis showed that gravitational habitat, but not body length, had a significant effect on Gz tolerance. At the extremes, carotid blood flow decreased in response to increasing G force and approached zero near +1 Gz in aquatic and ground-dwelling species, whereas in climbing species carotid flow was maintained at forces in excess of +2 Gz. Tolerant (arboreal) species were able to withstand hypergravic forces of +2 to +3 Gz for periods up to 1 h without cessation of carotid blood flow or loss of body movement and tongue flicking. Data suggest that the relatively tight skin characteristic of tolerant species provides a natural antigravity suit and is of prime importance in counteracting Gz stress on blood circulation.

  6. Tolerance of Snakes to Hypergravity

    Science.gov (United States)

    Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.

    1994-01-01

    Sensitivity of carotid blood flow to +Gz (head-to-tail) acceleration was studied in six species of snakes hypothesized to show varied adaptive cardiovascular responses to gravity. Blood flow in the proximal carotid artery was measured in 15 snakes before, during and following stepwise increments of +0.25Gz force produced on a 2.4 m diameter centrifuge. During centrifugation each snake was confined to a straight position within an individually- fitted acrylic tube with the head facing the center of rotation. We measured the centrifugal force at the tail of the snake in order to quantify the maximum intensity of force gradient promoting antero-posterior pooling of blood. Tolerance to increased gravity was quantified as the acceleration force at which carotid blood flow ceased. This parameter varied according to the gravitational adaptation of species defined by their ecology and behavior. At the extremes, carotid blood flow decreased in response to increasing gravity and approached zero near +1Gz in aquatic and ground-dwelling species, whereas in climbing species carotid flow was maintained at forces in excess of +2Gz. Surprisingly, tolerant (arboreal) species withstood hypergravic forces of +2 to +3 G. for periods up to 1 h without cessation of carotid blood flow or apparent loss of consciousness. Data suggest that relatively tight skin of the tolerant species provides a natural antigravity suit which is of prime importance in counteracting Gz stress on blood circulation.

  7. Modeling shade tree use by beef cattle as a function of black globe temperature and time of day

    Science.gov (United States)

    Foust, Amanda M.; Headlee, William L.

    2017-12-01

    Increasing temperatures associated with global climate change threaten to disrupt agricultural systems such as beef production, yet relatively little is known about the use of natural tree shade to mitigate the negative effects of heat stress on beef cattle. In this study, we evaluated how temperature and time of day influenced the utilization of tree shade in relation to coloration, orientation, and behavior of beef cattle in a pasture system. Temperatures in shade and direct sunlight were measured using black globe temperature (BGT) data loggers. Time-lapse images from game cameras were used to obtain counts of shade usage, coloration, orientation, and behavior of cattle throughout the daytime hours. In general, we found that shade utilization and most of the predominating orientations and behaviors differed significantly ( P effects (Hour × BGTsun) were often nonsignificant. The mean percentage of the herd using shade was highest in mid-morning (87-96%) and early afternoon (97%), but also increased with BGTsun regardless of the time of day; these trends were similar for both dark- and light-colored cattle. Lying down was the dominant behavior exhibited in the shade, while foraging was the most prevalent behavior in the sun. When herd shade usage was lowest in mid- to late-afternoon (<1%) we also observed an increase in the use of heat-mitigating orientations in the sun (37-47%). We discuss some practical implications of these results, including the potential use of temperature thresholds to interpret cattle behaviors and shade usage.

  8. Lactose tolerance tests

    Science.gov (United States)

    Hydrogen breath test for lactose tolerance ... Two common methods include: Lactose tolerance blood test Hydrogen breath test The hydrogen breath test is the preferred method. It measures the amount of hydrogen ...

  9. 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.

  10. 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.

  11. 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.

  12. Cooling and energy saving potentials of shade trees and urban lawns in a desert city

    International Nuclear Information System (INIS)

    Wang, Zhi-Hua; Zhao, Xiaoxi; Yang, Jiachuan; Song, Jiyun

    2016-01-01

    Highlights: • We developed a numerical framework incorporating trees in an urban canopy model. • Shade trees have more prominent energy saving potential than urban lawns. • The trade-off between water-energy is a key for urban landscape management. • Urban vegetation can significantly alleviate outdoor thermal stress. - Abstract: The use of urban vegetation in cities is a common landscape planning strategy to alleviate the heat island effect as well as to enhance building energy efficiency. The presence of trees in street canyons can effectively reduce environmental temperature via radiative shading. However, resolving shade trees in urban land surface models presents a major challenge in numerical models, especially in predicting the radiative heat exchange in canyons. In this paper, we develop a new numerical framework by incorporating shade trees into an advanced single-layer urban canopy model. This novel numerical framework is applied to Phoenix metropolitan area to investigate the cooling effect of different urban vegetation types and their potentials in saving building energy. It is found that the cooling effect by shading from trees is more significant than that by evapotranspiration from lawns, leading to a considerable saving of cooling load. In addition, analysis of human thermal comfort shows that urban vegetation plays a crucial role in creating a comfortable living environment, especially for cities located in arid or semi-arid region.

  13. Personal exposure distribution of solar erythemal ultraviolet radiation in tree shade over summer

    International Nuclear Information System (INIS)

    Parisi, A.V.; Wong, J.C.F.

    2000-01-01

    The personal radiant exposure distribution of solar erythemal UV in tree shade for an upright posture was measured, with measurements over the whole summer for a total of 17 trees. For each tree, the personal radiant exposure distribution was measured for both the morning and afternoon periods. The exposure ratios averaged over all the trees and over the morning and afternoon periods ranged from 0.16 to 0.49 for the different anatomical sites. A numerical model was employed to estimate the UV radiant exposure to humans in tree shade over the entire summer. The body sites with the higher exposure ratios in the tree shade were the vertex of the head, shoulders and forearms with radiant exposures over the summer of 1300 MED to the vertex of the head and 1100 MED to the shoulders and forearms. These radiant exposures in the shade are substantially higher than the ambient erythemal UV measured in full sun on a horizontal plane over a full summer at a more temperate northern hemisphere latitude. The average radiant exposures per day to each anatomical site for a complete day in the tree shade ranged from 4.6 to 14.6 MED. This research has provided new data that is essential to quantify human UV exposure during outdoor activities. (author)

  14. Analysis and Comparison of Shading Strategies to Increase Human Thermal Comfort in Urban Areas

    Directory of Open Access Journals (Sweden)

    Ivan Lee

    2018-03-01

    Full Text Available With the expected increase in warmer conditions caused by climate change, heat-related illnesses are becoming a more pressing issue. One way that humans can protect themselves from this is to seek shade. The design of urban spaces can provide individuals with a variety of ways to obtain this shade. The objective of this study was to perform a detailed evaluation and comparison of three shading strategies that could be used in an urban environment: shade from a building, from a tree, and from an umbrella. This was done through using field measurements to calculate the impact of each strategy on a thermal comfort index (Comfort Formula (COMFA in two urban settings during sunny days of the summer of 2013 and 2014 in London, Canada. Building shade was found to be the most effective cooling strategy, followed by the tree strategy and the umbrella strategy. As expected, the main determinant of this ranking was a strategy’s ability to block incoming shortwave radiation. Further analysis indicated that changes in the convective loss of energy and in longwave radiation absorption had a smaller impact that caused variations in the strategy effectiveness between settings. This suggests that under non-sunny days, these rankings could change.

  15. Development of digital shade guides for color assessment using a digital camera with ring flashes.

    Science.gov (United States)

    Tung, Oi-Hong; Lai, Yu-Lin; Ho, Yi-Ching; Chou, I-Chiang; Lee, Shyh-Yuan

    2011-02-01

    Digital photographs taken with cameras and ring flashes are commonly used for dental documentation. We hypothesized that different illuminants and camera's white balance setups shall influence color rendering of digital images and affect the effectiveness of color matching using digital images. Fifteen ceramic disks of different shades were fabricated and photographed with a digital camera in both automatic white balance (AWB) and custom white balance (CWB) under either light-emitting diode (LED) or electronic ring flash. The Commission Internationale d'Éclairage L*a*b* parameters of the captured images were derived from Photoshop software and served as digital shade guides. We found significantly high correlation coefficients (r² > 0.96) between the respective spectrophotometer standards and those shade guides generated in CWB setups. Moreover, the accuracy of color matching of another set of ceramic disks using digital shade guides, which was verified by ten operators, improved from 67% in AWB to 93% in CWB under LED illuminants. Probably, because of the inconsistent performance of the flashlight and specular reflection, the digital images captured under electronic ring flash in both white balance setups revealed less reliable and relative low-matching ability. In conclusion, the reliability of color matching with digital images is much influenced by the illuminants and camera's white balance setups, while digital shade guides derived under LED illuminants with CWB demonstrate applicable potential in the fields of color assessments.

  16. Online investigation of respiratory quotients in Pinus sylvestris and Picea abies during drought and shading by means of cavity-enhanced Raman multi-gas spectrometry.

    Science.gov (United States)

    Hanf, Stefan; Fischer, Sarah; Hartmann, Henrik; Keiner, Robert; Trumbore, Susan; Popp, Jürgen; Frosch, Torsten

    2015-07-07

    Photosynthesis and respiration are major components of the plant carbon balance. During stress, like drought, carbohydrate supply from photosynthesis is reduced and the Krebs cycle respiration must be fueled with other stored carbon compounds. However, the dynamics of storage use are still unknown. The respiratory quotient (RQ, CO2 released per O2 consumed during respiration) is an excellent indicator of the nature of the respiration substrate. In plant science, however, online RQ measurements have been challenging or even impossible so far due to very small gas exchange fluxes during respiration. Here we apply cavity-enhanced multi-gas Raman spectrometry (CERS) for online in situ RQ measurements in drought-tolerant pine (Pinus sylvestris [L.]) and drought-intolerant spruce (Picea abies [L. H. Karst]). Two different treatments, drought and shading, were applied to reduce photosynthesis and force dependency on stored substrates. Changes in respiration rates and RQ values were continuously monitored over periods of several days with low levels of variance. The results show that both species switched from COH-dominated respiration (RQ = 1.0) to a mixture of substrates during shading (RQ = 0.77-0.81), while during drought only pine did so (RQ = 0.75). The gas phase measurements were complemented by concentration measurements of non-structural carbohydrates and lipids. These first results suggest a physiological explanation for greater drought tolerance in pine. CERS was proven as powerful technique for non-consumptive and precise real-time monitoring of respiration rates and respirational quotients for the investigation of plant metabolism under drought stress conditions that are predicted to increase with future climate change.

  17. 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.

  18. 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...

  19. Computer simulation of shading and blocking: Discussion of accuracy and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Lipps, F.W. (Houston Univ., TX (United States))

    1992-04-01

    A field of heliostats suffers losses caused by shading and blocking by neighboring heliostats. The complex geometry of multiple shading and blocking events suggests that a processing code is needed to update the boundary vector for each shading or blocking event. A new version, RSABS, (programmer's manual included) simulates the split-rectangular heliostat. Researchers concluded that the dominant error for the given heliostat geometry is caused by the departure from planarity of the neighboring heliostats. It is recommended that a version of the heliostat simulation be modified to include losses due to nonreflective structural margins, if they occur. Heliostat neighbors should be given true guidance rather than assumed to be parallel, and the resulting nonidentical quadrilateral images should be processed, as in HELIOS, by ignoring overlapping events, rare in optimized fields.

  20. Computer simulation of shading and blocking: Discussion of accuracy and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Lipps, F W [Houston Univ., TX (United States)

    1992-04-01

    A field of heliostats suffers losses caused by shading and blocking by neighboring heliostats. The complex geometry of multiple shading and blocking events suggests that a processing code is needed to update the boundary vector for each shading or blocking event. A new version, RSABS, (programmer`s manual included) simulates the split-rectangular heliostat. Researchers concluded that the dominant error for the given heliostat geometry is caused by the departure from planarity of the neighboring heliostats. It is recommended that a version of the heliostat simulation be modified to include losses due to nonreflective structural margins, if they occur. Heliostat neighbors should be given true guidance rather than assumed to be parallel, and the resulting nonidentical quadrilateral images should be processed, as in HELIOS, by ignoring overlapping events, rare in optimized fields.

  1. Numerical model analysis of the shaded dye-sensitized solar cell module

    International Nuclear Information System (INIS)

    Chen Shuanghong; Weng Jian; Huang Yang; Zhang Changneng; Hu Linhua; Kong Fantai; Wang Lijun; Dai Songyuan

    2010-01-01

    On the basis of a numerical model analysis, the photovoltaic performance of a partially shadowed dye-sensitized solar cell (DSC) module is investigated. In this model, the electron continuity equation and the Butler-Vollmer equation are applied considering electron transfer via the interface of transparent conducting oxide/electrolyte in the shaded DSC. The simulation results based on this model are consistent with experimental results. The influence of shading ratio, connection types and the intensity of irradiance has been analysed according to experiments and numerical simulation. It is found that the performance of the DSC obviously declines with an increase in the shaded area due to electron recombination at the TCO/electrolyte interface and that the output power loss of the shadowed DSC modules in series is much larger than that in parallel due to the 'breakdown' occurring at the TCO/electrolyte interface. The impact of shadow on the DSC performance is stronger with increase in irradiation intensity.

  2. Measurements of the solar UVR protection provided by shade structures in New Zealand primary schools.

    Science.gov (United States)

    Gies, Peter; Mackay, Christina

    2004-01-01

    To reduce ultraviolet radiation (UVR) exposure during childhood, shade structures are being erected in primary schools to provide areas where children can more safely undertake outdoor activities. This study to evaluate the effectiveness of existing and purpose built shade structures in providing solar UVR protection was carried out on 29 such structures in 10 schools in New Zealand. Measurements of the direct and scattered solar UVR doses within the central region of the shade structures were made during the school lunch break period using UVR-sensitive polysulfone film badges. These measurements indicate that many of the structures had UVR protection factors (PF) of 4-8, which was sufficient to provide protection during the school lunch hour. However, of the 29 structures examined, only six would meet the suggested requirements of UVR PF greater than 15 required to provide all-day protection.

  3. [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 ( Pceramic veneers 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.

  4. 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 interpretations of recognition and toleration are considered, confusing and problematic uses of the terms are noted, and the compatibility of toleration and recognition is discussed. The article argues that there is a range of legitimate and importantly different conceptions of both toleration and recognition...

  5. 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 is a separation be-tween the feedback controller and the fault tolerant part. The closed loop feedback properties are handled by the nominal feedback controller and the fault tolerant part is handled by the design of the Youla parameter. The design of the fault tolerant part will not affect the design...... of the nominal feedback con-troller....

  6. 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.

  7. Optimal sun-shading design for enhanced daylight illumination of subtropical classrooms

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Ming-Chin [Architecture and Building Research Institute, MOI (China); Chiang, Che-Ming [Department of Architecture, National Cheng-Kung University, Tainan 701 (China); Chou, Po-Cheng [Department of Interior Design, Shu-Te University, No. 59 Hun-Shan Road, Yenchau 82445, Kaohsiung County (China); Chang, Kuei-Feng [Department of Real Estate Management, National Pingtung Institute of Commerce (China); Lee, Chia-Yen [Department of Mechanical and Automation Engineering, Da-Yeh University, Changhua 515 (China)

    2008-07-01

    This study investigates the feasibility of fitting windows with sun-shadings in order to minimize the lighting power costs in daylight-illuminated classrooms lit from a single side in subtropical regions. An IES-CPC model is created of a representative classroom in Taiwan, and a series of simulations is performed to determine the average illuminance value and the uniformity of the illuminance distribution in the classroom under various lighting conditions with no sun-shadings fitted to the window. The numerical results are found to be in good agreement with the experimental measurements obtained using an array of nine-channel photometers. Having confirmed the validity of the simulation scheme, the illumination properties of four different sun-shading designs are considered. The results show that a double-layered sun-shading represents the optimal sun-shading design in terms of achieving a uniform illumination distribution within the classroom. Given appropriate physical dimensions, this daylight access device achieves the minimum illuminance requirement of 500 lx and improves the lighting uniformity ratio from 0.25-0.35 to 0.40-0.42. Furthermore, using this sun-shading device, the required illuminance ratio of 0.5 can be obtained simply by switching on one of the three rows of lights in the classroom. Accordingly, the daylight access device not only improves the illuminance conditions within the classroom, but also reduces the lighting power cost by 71.5% compared to the case where all of the lights are turned on. (author)

  8. 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.

  9. Individual Plasticity of the Shade Response of the Invasive Solidago canadensis in China.

    Science.gov (United States)

    Du, Leshan; Liu, Haiyan; Yan, Ming; Li, Junmin; Li, Junsheng

    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 (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.

  10. Comparison of Shade of Ceramic with Three Different Zirconia Substructures using Spectrophotometer.

    Science.gov (United States)

    Habib, Syed Rashid; Shiddi, Ibraheem F Al

    2015-02-01

    This study assessed how changing the Zirconia (Zr) substructure affected the color samples after they have been overlaid by the same shade of veneering ceramic. Three commercial Zr materials were tested in this study: Prettau(®) Zirconia (ZirKonZahn, Italy), Cercon (Dentsply, Germany) and InCoris ZI (Sirona, Germany). For each system, 15 disk-shaped specimens (10 × 1 mm) were fabricated. Three shades of A1, A2 and A3.5 of porcelain (IPS e.MaxCeram, IvoclarVivadent, USA) were used for layering the specimens. Five specimens from each type of Zr were layered with same shade of ceramic. Color measurements were recorderd by a spectrophotometer Color-Eye(®) 7000A (X-Rite, Grand Rapids, MI). Mean values of L, a, b color coordinates and ΔE were recorded and comparisons were made. Differences in the ΔE were recorded for the same porcelain shade with different Zr substructures and affected the color of the specimens (p < 0.01, ANOVA). The maximum difference between the ΔE values for the A1, A2 and A3.5 shades with three types of Zr substructures was found to be 1.59, 1.69 and 1.45 respectively. Multiple comparisons of the ΔE with PostHoc Tukey test revealed a statistically significant difference (p < 0.05) between the three types of Zr, except between Type 2 Zr and Type 3 Zr for the Shade A1. The mean values of L, a, b and ΔE for the Prettau(®) Zirconia substructure were found to be the least among the three types. The brand of Zr used influences the final color of the all ceramic Zr based restorations and this has clinical significance.

  11. 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.

  12. 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.

  13. Effect of esthetic core shades on the final color of IPS Empress all-ceramic crowns.

    Science.gov (United States)

    Azer, Shereen S; Ayash, Ghada M; Johnston, William M; Khalil, Moustafa F; Rosenstiel, Stephen F

    2006-12-01

    Clinically relevant assessment of all-ceramic crowns supported by esthetic composite resin foundations has not been evaluated with regard to color reproducibility. This in vitro study quantitatively evaluated the influence of different shades of composite resin foundations and resin cement on the final color of a leucite-reinforced all-ceramic material. A total of 128 disks were fabricated; 64 (20 x 1 mm) were made of all-ceramic material (IPS Empress) and 64 (20 x 4 mm) of 4 different shades composite resin (Tetric Ceram). The ceramic and composite resin disks were luted using 2 shades (A3 and Transparent) of resin cement (Variolink II). Color was measured using a colorimeter configured with a diffuse illumination/0-degree viewing geometry, and Commission Internationale de l'Eclairage (CIE) L( *)a( *)b( *) values were directly calculated. Descriptive statistical analysis was performed, and color differences (DeltaE) for the average L( *), a( *) and b( *) color parameters were calculated. Repeated measures analysis of variance (ANOVA) was used to compare mean values and SDs between the different color combinations (alpha=.05). The CIE L( *)a( *)b( *) color coordinate values showed no significant differences for variation in color parameters due to the effect of the different composite resin shades (P=.24) or cement shades (P=.12). The mean color difference (DeltaE) value between the groups was 0.8. Within the limitations of this study, the use of different shades for composite resin cores and resin cements presented no statistically significant effect on the final color of IPS Empress all-ceramic material.

  14. 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 (p<0.05). Group 1 (20.7 ± 0.5) (IPS-CAD without resin 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 (p<0.05). Resin 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.

  15. 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.)

  16. 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

  17. A simulation-powered approach to ventilation, lighting and shading systems control

    Energy Technology Data Exchange (ETDEWEB)

    Schuss, Matthias; Proeglhoef, Claus; Orehounig, Kristina; Mahdavi, Ardeshir [Department of Building Physics and Building Ecology, Vienna University of Technology (Austria)

    2010-12-15

    This paper reports on ongoing work toward implementing a predictive control approach for buildings systems for ventilation, lighting, and shading. The main objective of this method is the optimized control of multiple devices toward usage of passive cooling and natural lighting. In this way, control options (various opening positions of windows, shades, etc.) are generated and computationally assessed using a combination of option space navigation via genetic algorithms and numeric simulation. (Copyright copyright 2010 Ernst and Sohn Verlag fuer Architektur und technische Wissenschaften GmbH and Co. KG, Berlin)

  18. Performance of a daylight redirecting glass shading system demonstration in an office building

    DEFF Research Database (Denmark)

    Appelfeld, David; Svendsen, Svend; Traberg-Borup, Steen

    2011-01-01

    This paper evaluates the daylighting performance of a prototype external dynamic integrated shading and light redirecting system. The demonstration project was carried out on a building with an open-plan office. The prototype and original façades were placed on the same floor with the same...... orientation and similar surroundings. The existing façade was used as the reference for measurements and simulations. The focus of this research project was to employ available simulation tools for the system performance evaluation. This was accompanied by measurements of the daylight conditions...... in the investigated space. The prototype system improved daylighting conditions compared to the existing shading system....

  19. 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.

  20. Theoretical and experimental analysis of daylight performance for various shading systems

    Energy Technology Data Exchange (ETDEWEB)

    Tsangrassoulis, A [Group Building Enviromental Studies, Lab. of Meteorology, Dept. of Applied Physics, Univ. of Athens (Greece); Santamouris, M [Group Building Enviromental Studies, Lab. of Meteorology, Dept. of Applied Physics, Univ. of Athens (Greece); Asimakopoulos, D [Group Building Enviromental Studies, Lab. of Meteorology, Dept. of Applied Physics, Univ. of Athens (Greece)

    1997-12-31

    The daylight coefficient approach is used for the theoretical analysis of various shading systems. Once a set of these coefficients has been calculated, it is very easy to calculate illuminance in the interior of a room under various sky luminance distributions. The present paper examines a method based on daylight coefficients to evaluate daylight in the interior of a room. The method is compared with existing radiosity and ray-tracing methods. The examined method is experimentaly validated using measurements obtained in a PASSYS test-cell equipped with shading devices. (orig.)

  1. Enhancing Dark Shade Pigment Dyeing of Cotton Fabric Using Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Chi-Wai Kan

    2017-07-01

    Full Text Available This study is intended to investigate the effect of atmospheric pressure plasma treatment on dark shade pigment dyeing of cotton fabric. Experimental results reveal that plasma-treated cotton fabric can attain better color yield, levelness, and crocking fastness in dark shade pigment dyeing, compared with normal cotton fabric (not plasma treated. SEM analysis indicates that cracks and grooves were formed on the cotton fiber surface where the pigment and the binder can get deposited and improve the color yield, levelness, and crocking fastness. It was also noticed that pigment was aggregated when deposited on the fiber surface which could affect the final color properties.

  2. 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.

  3. Occupants’ satisfaction with the visual environment in a single office with individual lighting and solar shading control

    DEFF Research Database (Denmark)

    Iversen, Anne; Nielsen, Toke Rammer; Svendsen, Svend

    2008-01-01

    A study was conducted in a test room equipped with an external reflecting solar shading system, energy efficient luminaires and a work station. The shading system reduces the illuminance level in the front of the room on days with clear sky and increases the illuminance in the back of the room...

  4. 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

  5. Tolerance to environmental desiccation in moss sperm.

    Science.gov (United States)

    Shortlidge, Erin E; Rosenstiel, Todd N; Eppley, Sarah M

    2012-05-01

    • Sexual reproduction in mosses requires that sperm be released freely into the environment before finding and fertilizing a receptive female. After release from the male plant, moss sperm may experience a range of abiotic stresses; however, few data are available examining stress tolerance of moss sperm and whether there is genetic variation for stress tolerance in this important life stage. • Here, we investigated the effects of environmental desiccation and recovery on the sperm cells of three moss species (Bryum argenteum, Campylopus introflexus, and Ceratodon purpureus). • We found that a fraction of sperm cells were tolerant to environmental desiccation for extended periods (d) and that tolerance did not vary among species. We found that this tolerance occurs irrespective of ambient dehydration conditions, and that the addition of sucrose during dry-down improved cell recovery. Although we observed no interspecific variation, significant variation among individuals within species in sperm cell tolerance to environmental desiccation was observed, suggesting selection could potentially act on this basic reproductive trait. • The observation of desiccation-tolerant sperm in multiple moss species has important implications for understanding bryophyte reproduction, suggesting the presence of a significant, uncharacterized complexity in the ecology of moss mating systems. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  6. (SSR) markers for drought tolerance in maize

    African Journals Online (AJOL)

    Maize is moderately sensitive to drought. Drought affects virtually all aspects of maize growth in varying degrees at all stages, from germination to maturity. Tolerance to drought is genetically and physiologically complicated and inherited quantitatively. Application of molecular-marker aided selection technique for ...

  7. 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...... is investigated. Conditions are given for closed-loop stability in case of false alarms or missing fault detection/isolation....

  8. Environmental tolerance of an invasive riparian tree and its potential for continued spread in the southwestern US

    Science.gov (United States)

    Reynolds, L.V.; Cooper, D.J.

    2010-01-01

    Questions: Exotic plant invasion may be aided by facilitation and broad tolerance of environmental conditions, yet these processes are poorly understood in species-rich ecosystems such as riparian zones. In the southwestern United States (US) two plant species have invaded riparian zones: tamarisk (Tamarix ramosissima, T. chinensis, and their hybrids) and Russian olive (Elaeagnus angustifolia). We addressed the following questions: (1) is Russian olive able to tolerate drier and shadier conditions than cottonwood and tamarisk? (2) Can tamarisk and cottonwood facilitate Russian olive invasion? Location: Arid riparian zones, southwestern US. Methods: We analyzed riparian tree seedling requirements in a controlled experiment, performed empirical field studies, and analyzed stable oxygen isotopes to determine the water sources used by Russian olive. Results: Russian olive survival was significantly higher in dense shade and low moisture conditions than tamarisk and cottonwood. Field observations indicated Russian olive established where flooding cannot occur, and under dense canopies of tamarisk, cottonwood, and Russian olive. Tamarisk and native riparian plant species seedlings cannot establish in these dry, shaded habitats. Russian olive can rely on upper soil water until 15 years of age, before utilizing groundwater. Conclusions: We demonstrate that even though there is little evidence of facilitation by cottonwood and tamarisk, Russian olive is able to tolerate dense shade and low moisture conditions better than tamarisk and cottonwood. There is great potential for continued spread of Russian olive throughout the southwestern US because large areas of suitable habitat exist that are not yet inhabited by this species. ?? 2010 International Association for Vegetation Science.

  9. 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...... 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...... 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...

  10. Acclimation of photosynthesis to lightflecks in tomato leaves: interaction with progressive shading in a growing canopy

    NARCIS (Netherlands)

    Kaiser, M.E.; Matsubara, Shizue; Harbinson, J.; Heuvelink, E.; Marcelis, L.F.M.

    2018-01-01

    Plants in natural environments are often exposed to fluctuations in light intensity, and leaf-level acclimation to light may be affected by those fluctuations. Concurrently, leaves acclimated to a given light climate can become progressively shaded as new leaves emerge and grow above them.

  11. Photovoltaics in the shade : One bypass diode per solar cell revisited

    NARCIS (Netherlands)

    Pannebakker, Boudewijn B.; de Waal, Arjen C.; van Sark, Wilfried G.J.H.M.

    2017-01-01

    Deployment of residential photovoltaic solar energy systems is strongly increasing, which gives rise to problems such as partial shading and pollution, omnipresent in the built environment. Conventional modules are sensitive to the current mismatches introduced by shadows because of their series

  12. Evaluating Maximum Photovoltaic Integration in District Distribution Systems Considering Optimal Inverter Dispatch and Cloud Shading Conditions

    DEFF Research Database (Denmark)

    Ding, Tao; Kou, Yu; Yang, Yongheng

    2017-01-01

    . However, the intermittency of solar PV energy (e.g., due to passing clouds) may affect the PV generation in the district distribution network. To address this issue, the voltage magnitude constraints under the cloud shading conditions should be taken into account in the optimization model, which can...

  13. Duration and intensity of shade differentially affects mycorrhizal growth- and phosphorus uptake responses of Medicago truncatula

    Czech Academy of Sciences Publication Activity Database

    Konvalinková, Tereza; Püschel, David; Janoušková, Martina; Gryndler, Milan; Jansa, Jan

    2015-01-01

    Roč. 6, FEB 13 (2015), s. 1-11 ISSN 1664-462X R&D Projects: GA MŠk(CZ) LK11224 Institutional support: RVO:61388971 Keywords : arbuscular mycorrhizal symbiosis * light intensity * shading duration Subject RIV: EE - Microbiology, Virology Impact factor: 4.495, year: 2015

  14. Can Management Improve the Value of Shade Plantations for the Endemic Species of Sao Tome Island?

    DEFF Research Database (Denmark)

    de Lima, Ricardo F.; Viegas, Leonel; Sole, Nelson

    2014-01-01

    Cocoa and coffee are among the most valuable tropical crops, with much of their production in areas of high biodiversity. Although this could suggest a conflict between agricultural expansion and biodiversity conservation, these crops are normally grown in shade plantations—a more biodiversity...

  15. A functional comparison of acclimation to shade and submergence in two terrestrial plant species

    NARCIS (Netherlands)

    Mommer, L.; Kroon, de H.; Pierik, R.; bögemann, G.M.; Visser, E.J.W.

    2005-01-01

    Terrestrial plants experience multiple stresses when they are submerged, caused both by oxygen deficiency due to reduced gas diffusion in water, and by shade due to high turbidity of the floodwater. It has been suggested that responses to submergence are de facto responses to low light intensity. •

  16. Solar energy efficiency of cocoa clones cultivated under three species of shade trees.

    Directory of Open Access Journals (Sweden)

    Oscar Regazzoni

    2015-04-01

    Full Text Available This experiment aims to know the solar energy efficiency of four clones of cocoa that cultivated under three different shading plants. This experiment has been done from September until December 2013 located at Kaliwining Experiment Farm with characteristic 45 m above sea level, soil type is low humic gley, soil texture is silty clay loam, and climate classification type D based on Scmidht and Fergusson Classification. This experiment used Nested Design as Experimental Design with species of shading plant as main plot which are Teak (Tectona grandis L., Krete (Cassia surattensis (Burm. F., Lamtoro (Leucaena leucocephala L. and Cocoa clones as sub plot which are Sulawesi 1, Sulawesi 2, KKM 22, KW 165. The observation of solar energy efficiency consists of daily solar radiation intensity, solar radiation intensity above plant, solar radiation intensity under plant, and also plant total dry weight. The experimental result showed that there is differences (heterogenity between shading location based on homogenity test by Bartlett Method. There are some interaction between the kind of shading plant and clones in parameter of interception efficiency, absorbtion efficiency, the efficiency of solar energy that caught by plant, and solar energy conversion efficiency. The efficiency of solar energy that caught by plant will affect the solar energy conversion efficiency with R2 = 0,86.

  17. The characterisation of the daylighting properties of special glazings and solar shading devices

    NARCIS (Netherlands)

    Dijk, H.A.L. van; Bakker, L.G.

    1998-01-01

    Within the EU DGXII R&D Programme JOULE a project, called REVIS. started in 1998 and will be completed within 2.5 years, with the objective to develop detailed daylight product information of novel products of glazings and solar shading devices. This involves a test procedure, definition of product

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

    African Journals Online (AJOL)

    The effect of three moisture levels and three shade regimes on the growth of D x P ex Kusi oil palm seedlings was investigated at the Oil Palm Research Institute, Kusi between July 1998 and February 2000 in a factorial experiment laid out in randomized complete block design with four replications. The moisture treatments ...

  19. 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 ...

  20. 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.

  1. Factors affecting long-term mortality of residential shade trees: evidence from Sacramento, California

    Science.gov (United States)

    Yekang Ko; Jun-Hak Lee; E. Gregory McPherson; Lara A. Roman

    2015-01-01

    Urban tree survival is essential to sustain the ecosystem services of urban forests and monitoring is needed to accurately assess benefits. While some urban forestry studies have reported street tree survival, little is known about the factors influencing residential yard tree survival, especially over the long-term. We assessed residential shade tree survival in...

  2. GROWTH OF Jacaranda puberula Cham. SEEDLINGS IN NURSERY UNDER DIFFERENT SHADING LEVELS

    Directory of Open Access Journals (Sweden)

    Lausanne Soraya de Almeida

    2010-08-01

    Full Text Available Jacaranda puberula, known as caroba, is a species that presents potential use for the recovery of degraded areas, since it possesses fast growth and adapts well to sandy and loamy soils. It presents great aggressiveness in secondary forests and it can be used as urban tree because it produces beautiful lilac flowers. With the intention of obtaining information about potential species for use in recovery of riparian forest, were tested in the nursery of the city hall of the municipal district of Colombo, the development of seedlings of Jacaranda puberula submitted at 30, 50 and 70% of shading. There were used 40 seedlings by treatment and there were evaluated the following parameters: height (60, 90 and 120 days and diameter (90 and 120 days of all seedlings, leaf area and root and shoot dry weight of 6 seedlings per treatment. The largest averages of the analyzed variables were obtained for the 30% shading, except for root dry weight.  The seedlings exposed to full sun presented high mortality rate and was not compared to the others. The smallest averages of the analyzed variables, except for height, were observed for the shading of 70%, indicating that this treatment is not advisable for the production of seedlings of this species in nursery. The best condition for planting the seedlings appears to be in open areas with shading of 30 to 50%, since its natural occurrence is not at full exposure.

  3. Photosynthetic behavior, growth and essential oil production of Melissa officinalis L. cultivated under colored shade nets

    Directory of Open Access Journals (Sweden)

    Graziele C Oliveira

    2016-03-01

    Full Text Available The modulation of light is of importance during cultivation of medicinal plants to obtain desirable morphological and physiological changes associated with the maximum production of active principles. This study aimed to evaluate the effect of the light spectrum transmitted by colored shade nets on growth, essential oil production and photosynthetic behavior in plants of lemon balm (Melissa officinalis L. Plants were cultivated in pots for 4-mo under black, red, and blue nets with 50% shading, and full sunlight exposure. Biometric and anatomical variables, essential oil yield, global solar radiation, photon flux density, chlorophyll content, and gas exchange parameters were measured in M. officinalis leaves. The results showed that despite being considered a partial shade plant, this species is able to adapt to full sunlight conditions without increasing biomass production. The spectral changes provided by colored shade nets did not caused any noticeable change in leaf anatomy of M. officinalis. However, the use of blue net resulted in increments of 116% in plant height, 168% in leaf area, 42% in chlorophyll content and 30% in yield of essential oil in lemon balm plants. These plant's qualities make the use of blue net a cultivation practice suitable for commercial use.

  4. Shading and vermicompost effect on growth and flavonoid content of Tapak Liman (Elephantopus scaber L.)

    Science.gov (United States)

    Dawiyah, R. Y. A.; Yunus, A.; Samanhudi; Widiyastuti, Y.; Widodo

    2018-03-01

    Tapak Liman (Elephantopus scaber L) is one of Indonesian medicinal plants which is well known as weed. In Thailand, Tapak Limanthis plant is use for traditional medicine due to its flavonoids contains. Flavonoid is compound with red, yellow, purple and blue pigments, used for cancer, aphrodiasiac and anti-radical treatments. One obstacle of Tapak liman cultivation is the effort to increase its flavonoids compound. There is a bridge between flavonoids compound with growth and yield of Tapak Liman. For that, this research aims to find out the effect of shade intensity combined with vermicompost dosage on Tapak Liman growth and yield. This research was conducted in Mei to August 2016 at Medicinal Plantation of BPTO, Tanjungsari Village, Tegal Gede, Karanganyar. Complete Randomized Design compiled with split plot and two factors: shade intensity (0%, 50%, 75%) and vermicompost dosage per plant (0 g, 250 g, 500 g, 750 g) used as the experimental design. The variables observed are leaves number,leaves length, canopy diameter, fresh weight, dry weight, root length, chlorophyl analysis and flavonoid identification. Data were analyzed using ANOVA, any significant treatments followed with Duncan’s Multiple Range Test (DMRT) at α = 10%. Result showed that 75% shade intesity and 750 g of vermicompost has gave highest yield of leaf and total simplicia of Tapak Liman. Shade intensity of 50% with 250 g of and 500 g/plant of vermicompost dosage showed highest flavonoid rendement (Rf 0,5) with highly contrasting spot colors.

  5. Fifty Shades a way readers put sex back in their lives

    DEFF Research Database (Denmark)

    Knudsen, Gry Høngsmark

    2014-01-01

    This is a guest blog from Gry Høngsmark Knudsen, a former student, who visited my “Women’s Economy” class this winter to report on her project about the reception of Fifty Shades of Grey. We all enjoyed her report, so I asked her to write a short blog for Double X Readers....

  6. A New Perspective on the Relationship Between Cloud Shade and Point Cloudiness

    Czech Academy of Sciences Publication Activity Database

    Brabec, Marek; Badescu, V.; Paulescu, M.; Dumitrescu, A.

    172-173, 15 May (2016), s. 136-146 ISSN 0169-8095 Institutional support: RVO:67985807 Keywords : point cloud iness * cloud shade * statistical analysis * semi-parametric modeling Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 3.778, year: 2016

  7. Normalized mutual information based PET-MR registration using K-Means clustering and shading correction

    NARCIS (Netherlands)

    Knops, Z.F.; Maintz, J.B.A.; Viergever, M.A.; Pluim, J.P.W.; Gee, J.C.; Maintz, J.B.A.; Vannier, M.W.

    2003-01-01

    A method for the efficient re-binning and shading based correction of intensity distributions of the images prior to normalized mutual information based registration is presented. Our intensity distribution re-binning method is based on the K-means clustering algorithm as opposed to the generally

  8. Effects of multiple disturbances in seagrass meadows : shading decreases resilience to grazing

    NARCIS (Netherlands)

    Eklof, Johan S.; McMahon, Kathryn; Lavery, Paul S.

    2009-01-01

    Ecosystem shifts are often associated with multiple disturbances, but limited knowledge on the mechanisms involved hampers management. This study investigated how short-term shading affected the resilience of the seagrass Halophila ovalis to grazing by black swans (Cygnus atratus) - a historically

  9. Sexist Attitudes Among Emerging Adult Women Readers of Fifty Shades Fiction.

    Science.gov (United States)

    Altenburger, Lauren E; Carotta, Christin L; Bonomi, Amy E; Snyder, Anastasia

    2017-02-01

    Stereotypical sexist representations of men and women in popular culture reinforce rigid views of masculinity (e.g., males as being strong, in control, masterful, and aggressive) and femininity (e.g., women as being fragile and weak, unassertive, peaceful, irrational, and driven by emotions). The present study examined associations between the fictional series Fifty Shades-one popular culture mechanism that includes pervasive traditional gender role representations-and underlying sexist beliefs among a sample of 715 women ages 18-24 years. Analyses revealed associations between Fifty Shades readership and sexism, as measured through the Ambivalent Sexism Inventory. Namely women who reported reading Fifty Shades had higher levels of ambivalent, benevolent, and hostile sexism. Further, those who interpreted Fifty Shades as "romantic" had higher levels of ambivalent and benevolent sexism. Our findings support prior empirical studies noting associations between interacting with aspects of popular culture, such as television and video games, and individual beliefs and behaviors.

  10. Trace gas emissions from a sun and shade grown ornamental crop

    Science.gov (United States)

    Previous work has begun to establish baseline approximations for greenhouse gas (GHG) (CO2, CH4, and N2O) emissions of several horticultural crops, though much work is still needed to expand contingencies for multiple best management practices. In this study, GHG emissions from one shade-grown speci...

  11. Diseases of Ornamental and Shade Trees, Shrubs, Vines, and Ground Covers.

    Science.gov (United States)

    Nichols, Lester P.

    This agriculture extension service publication from Pennsylvania State University covers the identification and control of common ornamental trees, shrubs, and ground cover diseases. The publication is divided into sections. The first section discusses the diseases of ornamental and shade trees, including general diseases and diseases of specific…

  12. Influence of neighboring plants on shading stress resistance and recovery of eelgrass, Zostera marina L.

    Directory of Open Access Journals (Sweden)

    Camilla Gustafsson

    Full Text Available Stressful environments may enhance the occurrence of facilitative interspecific interactions between plants. In several regions, Zostera marina occurs in mixed assemblages. However, the potential effects of plant diversity on stress responses and stability properties of Z. marina are poorly understood. We investigated the resistance and recovery of Z. marina subjected to shading (1 mo in a field experiment lasting 2.5 mo. We shaded Z. marina planted in mono- and polycultures (Potamogeton perfoliatus, P. pectinatus, P. filiformis in a factorial design (Shading×Richness at 2 m depth. We estimated the resistance and recovery of Z. marina by measuring four response variables. Polyculture Z. marina lost proportionally less biomass than monocultures, thus having a greater resistance to shading. In contrast, after a 1 mo recovery period, monocultures exhibited higher biomass gain, and a faster recovery than polycultures. Our results suggest that plant species richness enhances the resistance of Z. marina through facilitative mechanisms, while the faster recovery in monocultures is possibly due to interspecific competition. Our results highlight the need of a much better understanding of the effects of interspecific interactions on ecosystem processes in mixed seagrass meadows, and the preservation of diverse plant assemblages to maintain ecosystem functioning.

  13. Plant responses to simultaneous stress of waterlogging and shade: amplified or hierarchical effects?

    NARCIS (Netherlands)

    Lenssen, J.P.M.; Menting, F.B.J.; Putten, van der 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

  14. Response of container-grown flowering dogwood cultivars to sun/shade production regime, 2015

    Science.gov (United States)

    Flowering dogwood, Cornus florida, ‘Cherokee Brave™’ and ‘Cherokee Princess’ were grown in #5 nursery containers in an amended 100% bark substrate. Treatments were assigned based on exposure time to a full sun/shade condition during the growing season: 1) plants grown in full sun, 2) plants grown in...

  15. Effects of sun and shade drying on nutrient and antinutrient content ...

    African Journals Online (AJOL)

    This work determined the effect of sun and shade drying on the nutrient, antinutrient and food toxicant composition of atama – Heinsia crinata, editan - Lasianthore Africana and water – leaf – Talinum tringulare vegetables. Two and a half kilogram of these green leafy vegetable were purchased from Uyo market, picked from ...

  16. Tolerance in Drosophila

    OpenAIRE

    Atkinson, Nigel S.

    2009-01-01

    The set of genes that underlie ethanol tolerance (inducible resistance) are likely to overlap with the set of genes responsible for ethanol addiction. Whereas addiction is difficult to recognize in simple model systems, behavioral tolerance is readily identifiable and can be induced in large populations of animals. Thus, tolerance lends itself to analysis in model systems with powerful genetics. Drosophila melanogaster has been used by a variety of laboratories for the identification of genes...

  17. Using a colorimeter to develop an intrinsic silicone shade guide for facial prostheses.

    Science.gov (United States)

    Over, L M; Andres, C J; Moore, B K; Goodacre, C J; Muñoz, C A

    1998-12-01

    To determine if using CIE L*a*b* color measurements of white facial skin could be correlated to those of silicone shade samples that visually matched the skin. Secondly, to see if a correlation in color measurements could be achieved between the silicone shade samples and duplicated silicone samples made using a shade-guide color formula. A color booth was designed according to ASTM specifications, and painted using a Munsell Value 8 gray. A Minolta colorimeter was used to make facial skin measurements on 15 white adults. The skin color was duplicated using custom-shaded silicone samples. A 7-step wedge silicone shade guide was then fabricated, representing the commonly encountered thicknesses when fabricating facial prostheses. The silicone samples were then measured with the Minolta colorimeter. The readings were compared with the previous L*a*b* readings from the corresponding patient's skin measurements, and the relative color difference was then calculated. Silicone samples were fabricated and analyzed for three of the patients to determine if duplication of the visually matched silicone specimen was possible using the silicone color formula, and if the duplicates were visually and colorimetrically equivalent to each other. The color difference Delta E and chromaticity was calculated, and the data were analyzed using a coefficient-of-variation formula expressed by percent. A Pearson Product Moment Correlation Coefficient was performed to determine if a correlation existed between the skin and the silicone samples at the p 0), but only the 1-mm and 4-mm b* readings were very strong. Patient and silicone L*a*b* measurement results showed very little change in the a* axis, while the L* and b* measurements showed more change in their numbers, with changes in depth for all patient silicone samples. Delta E numbers indicated the lowest Delta E at the 1-mm depth and the highest Delta E at the 10-mm depth. All duplicated samples matched their original silicone samples

  18. Radiant heat loss, an unexploited path for heat stress reduction in shaded cattle.

    Science.gov (United States)

    Berman, A; Horovitz, T

    2012-06-01

    Reducing thermal radiation on shaded animals reduces heat stress independently of other means of stress relief. Radiant heat exchange was estimated as a function of climate, shade structure, and animal density. Body surface portion exposed to radiant sources in shaded environments was determined by geometrical relations to determine angles of view of radiation sources (roof underside, sky, sun-exposed ground, shaded ground) on the animal's surface. The relative representation of environment radiation sources on the body surface was determined. Animal thermal radiation balance was derived from radiant heat gained from radiation sources (including surrounding animals) and that lost from the animal surface. The animal environment was assumed to have different shade dimensions and temperatures. These were summed to the radiant heat balance of the cow. The data formed served to estimate the effect of changes in intensity of radiation sources, roof and shaded surface dimensions, and animal density on radiant heat balance (Rbal) of cattle. Roof height effect was expressed by effect of roof temperature on Rbal. Roof underside temperature (35 to 75°C) effect on Rbal was reduced by roof height. If roof height were 4m, an increase in its underside temperature from 35 to 75°C would increase mean Rbal from -63 to -2 W·m⁻², whereas if roof height were 10 m, Rbal would only increase from -99 to -88 W·m⁻². A hot ground temperature increase from 35 to 65°C reduced mean Rbal heat loss from -45 to 3 W·m⁻². Increasing the surface of the shaded area had only a minor effect on Rbal and on the effect of hot ground on Rbal. Increasing shade roof height reduced the effect of roof temperature on Rbal to minor levels when height was > 8m. Increasing the roof height from 4 to 10 m decreased Rbal from -32 to -94 W·m⁻². Increasing indirect radiation from 100 to 500 W·m⁻² was associated with an increase in Rbal from -135 to +23 W·m⁻². Their combined effects were lower

  19. Shade Sails and Passive Recreation in Public Parks of Melbourne and Denver: A Randomized Intervention

    Science.gov (United States)

    English, Dallas R.; Buller, Mary Klein; Simmons, Jody; Chamberlain, James A.; Wakefield, Melanie; Dobbinson, Suzanne

    2017-01-01

    Objectives. To test whether shade sails will increase the use of passive recreation areas (PRAs). Methods. We conducted a stratified randomized pretest–posttest controlled design study in Melbourne, Australia, and Denver, Colorado, in 2010 to 2014. We randomized a sample of 144 public parks with 2 PRAs in full sun in a 1:3 ratio to treatment or control. Shade sails were built at 1 PRA per treatment park. The outcome was any use of the study PRA (n = 576 pretest and n = 576 posttest observations; 100% follow-up). Results. Compared with control PRAs (adjusted probability of use: pretest = 0.14, posttest = 0.17), use of treatment PRAs (pretest = 0.10, posttest = 0.32) was higher at posttest (odds ratio [OR] = 3.91; 95% confidence interval [CI] = 1.71, 8.94). Shade increased use of PRAs in Denver (control: pretest = 0.18, posttest = 0.19; treatment: pretest = 0.16, posttest = 0.47) more than Melbourne (control: pretest = 0.11, posttest = 0.14; shaded: pretest = 0.06, posttest = 0.19; OR = 2.98; 95% CI = 1.09, 8.14). Conclusions. Public investment in shade is warranted for skin cancer prevention and may be especially useful in the United States. Trial Registration. Clinicaltrials.gov identifier NCT02971709. PMID:29048958

  20. Making biodiversity-friendly cocoa pay: combining yield, certification, and REDD for shade management.

    Science.gov (United States)

    Waldron, A; Justicia, R; Smith, L E

    2015-03-01

    The twin United Nations' Millennium Development Goals of biodiversity preservation and poverty reduction both strongly depend on actions in the tropics. In particular, traditional agroforestry could be critical to both biological conservation and human livelihoods in human-altered rainforest areas. However, traditional agroforestry is rapidly disappearing, because the system itself is economically precarious, and because the forest trees that shade traditional crops are now perceived to be overly detrimental to agricultural yield. Here, we show a case where the commonly used agroforestry shade metric, canopy cover, would indeed suggest complete removal of shade trees to maximize yield, with strongly negative biodiversity and climate implications. However, a yield over 50% higher was achievable if approximately 100 shade trees per hectare were planted in a spatially organized fashion, a win-win for biodiversity and the smallholder. The higher yield option was detected by optimizing simultaneously for canopy cover, and a second shade metric, neighboring tree density, which was designed to better capture the yield value of ecological services flowing from forest trees. Nevertheless, even a 50% yield increase may prove insufficient to stop farmers converting away from traditional agroforestry. To further increase agroforestry rents, we apply our results to the design of a sustainable certification (eco-labelling) scheme for cocoa-based products in a biodiversity hotspot, and consider their implications for the use of the United Nations REDD (reducing emissions from deforestation and forest degradation) program in agroforestry systems. Combining yield boost, certification, and REDD has the potential to incentivize eco-friendly agroforestry and lift smallholders out of poverty, simultaneously.

  1. Solar shading for low energy use and daylight quality in offices: Simulations, measurements and design tools

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, M.C.

    2001-11-01

    This thesis investigates the impact of solar shading devices on energy use and daylight quality in office rooms. The impact on energy use is analysed through computer simulations with the dynamic energy simulation program Derob-LTH while the impact on daylight quality is investigated through measurements in full-scale experimental office rooms and simulations with the program Radiance. This thesis also includes a literature review of research on solar shading as well as design tools to incorporate shading devices at an early stage in the design of buildings. This thesis indicates that, in cold countries, shading devices may provide more annual energy savings than any solar-protective (reflective, tinted) glazing and that the optimum glazing transmittance is orientation- and climate-dependent. For example, high annual energy savings are obtained on the south facade with higher transmittance glazings (compared with the east and west facade) because the potential for passive solar gain utilisation in the winter is high in comparison with the annual cooling demand. Exterior shading devices like awnings and overhangs may reduce the cooling demand dramatically but they are not suitable as daylight (glare) control devices. Devices like screens and venetian blinds are preferable because they cover the entire window area, which prevents sunlight patches in the room and the direct view of the bright sky. Screens and venetian blinds also reduce daylight in the room to levels that are suitable for computer work. However, it is essential that the screen is of a diffusing type since screens with a strong (specular) transmittance component result in poor daylight quality. The study on daylight quality also indicated that a screen transmittance of around 15 % may be optimum for a standard (3.5 by 6.0 m{sup 2}) south-oriented office room with a window covering around 25 % of the facade area (12 % of the floor area)

  2. Effect of ceramic thickness and shade on mechanical properties of a resin luting agent.

    Science.gov (United States)

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

    2014-08-01

    This study aimed to investigate the influence of ceramic thickness and shade on the Knoop hardness and dynamic elastic modulus of a dual-cured resin cement. Six ceramic shades (Bleaching, A1, A2, A3, A3.5, B3) and two ceramic thicknesses (1 mm, 3 mm) were evaluated. Disk specimens (diameter: 7 mm; thickness: 2 mm) of the resin cement were light cured under a ceramic block. Light-cured specimens without the ceramic block at distances of 1 and 3 mm were also produced. The Knoop hardness number (KHN), density, and dynamic Young's moduli were determined. Statistical analysis was conducted using ANOVA and a Tukey B rank order test (p = 0.05). The bleaching 1-mm-thick group exhibited significantly higher dynamic Young's modulus. Lower dynamic Young's moduli were observed for the 3-mm-thick ceramic groups compared to bleaching 3-mm-thick group, and no difference was found among the other 3-mm groups. For the KHN, when A3.5 3-mm-thick was used, the KHN was significantly lower than bleaching and A1 1-mm-thick ceramic; however, no difference was exhibited between the thicknesses of the same shade. The dual-cured resin cement studied irradiated through the 1-mm-thick ceramic with the lightest shade (bleaching ceramic) exhibited a better elastic modulus, and there was no effect in KHN of the resin cement when light cured under different ceramic shades and thicknesses (1 and 3 mm), except when the A3.5 3-mm-thick ceramic was used. Variolink II irradiated through ceramic with the lowest chroma exhibited the highest elastic modulus; therefore, the light activation method might not be the same for all clinical situations. © 2014 by the American College of Prosthodontists.

  3. Shade Sails and Passive Recreation in Public Parks of Melbourne and Denver: A Randomized Intervention.

    Science.gov (United States)

    Buller, David B; English, Dallas R; Buller, Mary Klein; Simmons, Jody; Chamberlain, James A; Wakefield, Melanie; Dobbinson, Suzanne

    2017-12-01

    To test whether shade sails will increase the use of passive recreation areas (PRAs). We conducted a stratified randomized pretest-posttest controlled design study in Melbourne, Australia, and Denver, Colorado, in 2010 to 2014. We randomized a sample of 144 public parks with 2 PRAs in full sun in a 1:3 ratio to treatment or control. Shade sails were built at 1 PRA per treatment park. The outcome was any use of the study PRA (n = 576 pretest and n = 576 posttest observations; 100% follow-up). Compared with control PRAs (adjusted probability of use: pretest = 0.14, posttest = 0.17), use of treatment PRAs (pretest = 0.10, posttest = 0.32) was higher at posttest (odds ratio [OR] = 3.91; 95% confidence interval [CI] = 1.71, 8.94). Shade increased use of PRAs in Denver (control: pretest = 0.18, posttest = 0.19; treatment: pretest = 0.16, posttest = 0.47) more than Melbourne (control: pretest = 0.11, posttest = 0.14; shaded: pretest = 0.06, posttest = 0.19; OR = 2.98; 95% CI = 1.09, 8.14). Public investment in shade is warranted for skin cancer prevention and may be especially useful in the United States. Clinicaltrials.gov identifier NCT02971709.

  4. VIDEO ANIMASI 3D PENGENALAN RUMAH ADAT DAN ALAT MUSIK KEPRI DENGAN MENGUNAKAN TEKNIK RENDER CEL-SHADING

    Directory of Open Access Journals (Sweden)

    Jianfranco Irfian Asnawi

    2016-11-01

    Full Text Available Animasi ini berjudul "video animasi 3D rumah adat dan alat musik Kepulauan Riau dengan menggunakan teknik render cel-shading" merupakan video yang bertujuan memperkenalkan alat-alat musik yang berasal dari kepulauan riau, Animasi ini akan diterapkan dengan menggunakan teknik render cel-shading. Cel-shading adalah teknik render yang menampilkan grafik 3D yang menyerupai gambar tangan, seperti gambar komik dan kartun. Teknik ini juga sudah di terapkan dalam game 3D yang ternyata menarik banyak perhatian peminat. Teknik ini akan di terapkan kedalam animasi 3D "video animasi rumah adat dan alat musik kepulauan riau dengan menggunakan teknik render cel-shading" Animasi di rancang menggunakan skenario dan storyboard kemudian di implementasikan dalam software 3D MAYA AUTODESK dengan menggunakan teknik render cel-shading. Setelah diterapkan maka di dapatkan definisi keberhasilan dari teknik render cel shading di bandingkan dengan teknik render global illumination seperti dari kecepatan dalam merender dan tingkat kecerahan warna pada video. Kata kunci: animasi, game 3D, cel-shading.

  5. Compromise and Toleration

    DEFF Research Database (Denmark)

    Rostbøll, Christian F.

    Political compromise is akin to toleration, since both consist of an "agreement to disagree." Compromise and toleration also share a predicament of being regarded as ambiguous virtues that require of us to accept something we actually regard as wrong. However, we misunderstand the nature, justifi...... in compromise are more stringent than those for being tolerated. Still, the limits of compromise cannot be drawn to narrowly if it is to remain its value as a form of agreement that respects and embodies the differences of opinion in society.......Political compromise is akin to toleration, since both consist of an "agreement to disagree." Compromise and toleration also share a predicament of being regarded as ambiguous virtues that require of us to accept something we actually regard as wrong. However, we misunderstand the nature......, justification, and limits of compromise if we see it merely as a matter of toleration. While toleration is mainly a matter of accepting citizens' equal right to co-existence as subjects to law, political compromise includes the parties in making law – it makes them co-authors of law. Toleration entails...

  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 computing systems

    International Nuclear Information System (INIS)

    Randell, B.

    1981-01-01

    Fault tolerance involves the provision of strategies for error detection damage assessment, fault treatment and error recovery. A survey is given of the different sorts of strategies used in highly reliable computing systems, together with an outline of recent research on the problems of providing fault tolerance in parallel and distributed computing systems. (orig.)

  8. 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...

  9. 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...

  10. Crescimento de capim-braquiária influenciado pelo grau de sombreamento e pela estação do ano Growth of signalgrass influenced by shading levels and season of the year

    Directory of Open Access Journals (Sweden)

    Domingos Sávio Campos Paciullo

    2008-07-01

    Full Text Available O objetivo deste trabalho foi avaliar, nas diferentes estações do ano, as características morfogênicas e estruturais e a produção de matéria seca de Brachiaria decumbens Stapf., cultivada em três graus de sombreamento: área de pastagem exclusivamente com B. decumbens, área próxima ao bosque e área com bosque de Eucalyptus grandis consorciado com leguminosas arbóreas (0, 18 e 50% de sombreamento, respectivamente. O delineamento experimental foi o de blocos ao acaso, com arranjo em parcelas subdivididas no tempo, com quatro repetições. O sombreamento induziu à elevação das taxas de alongamento de folhas e colmos. A taxa de aparecimento de folhas e o número de folhas vivas por perfilho não foram influenciados pelos graus de sombreamento. Em geral, no inverno houve redução nos valores das variáveis morfogenéticas e estruturais do dossel, assim como das taxas de produção de forragem, independentemente do sombreamento. A braquiária apresenta plasticidade fenotípica, em resposta às variações climáticas sazonais e aos níveis de sombreamento ambiental, o que confere a essa espécie elevado potencial para uso em sistemas silvipastoris.The objective of this work was to evaluate, in different seasons of the year, the morphogenetic and structural traits and dry matter production of Brachiaria decumbens Stapf., established under three shading conditions: exclusive B. decumbens pasture, area distant 12 m from trees, and area under trees cultivated with Eucalyptus grandis mixed with leguminous trees (0, 18 and 50% shading level, respectively. The experimental design was the randomized blocks, in a split plot array in time, with four replications. Shade caused an increase of leaf and stem elongation rates. Shading levels have not influenced leaf appearance rates and leaf number per tiller. Morphogenetic and structural traits and herbage production rates reduced during winter, independently of shading level. Signalgrass presents

  11. 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......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 invoking a critique external to contemporary democratic theory, but by witnessing the history of tolerance paraliptically, with an eye to what it obscures and yet presupposes....

  12. 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.        

  13. A Simple Checking Algorithm with Perturb and Observe Maximum Power Point Tracking for Partially Shaded Photovoltaic System

    Directory of Open Access Journals (Sweden)

    Rozana Alik

    2016-03-01

    Full Text Available This paper presents a simple checking algorithm for maximum power point tracking (MPPT technique for Photovoltaic (PV system using Perturb and Observe (P&O algorithm. The main benefit of this checking algorithm is the simplicity and efficiency of the system whose duty cycle produced by the MPPT is smoother and changes faster according to maximum power point (MPP. This checking algorithm can determine the maximum power first before the P&O algorithm takes place to identify the voltage at MPP (VMPP, which is needed to calculate the duty cycle for the boost converter. To test the effectiveness of the algorithm, a simulation model of PV system has been carried out using MATLAB/Simulink under different level of irradiation; or in other words partially shaded condition of PV array. The results from the system using the proposed approach prove to have faster response and low ripple. Besides, the results are close to the desired outputs and exhibit an approximately 98.25% of the system efficiency. On the other hand, the system with conventional P&O MPPT seems to be unstable and has higher percentage of error. In summary, the proposed method is useful under varying level of irradiation with higher efficiency of the system.

  14. Effects of shading on photosynthesis, plant organic nitrogen uptake and root fungal colonization in a subarctic mire ecosystem

    DEFF Research Database (Denmark)

    Olsrud, Hanna Maria Kerstin; Michelsen, Anders

    2009-01-01

    Arctic dwarf shrub ecosystems are predicted to be exposed to lower light intensity in a changing climate where mountain birch forests are expanding. We investigated how shading at 0%, 65%, and 97% affects photosynthesis, organic N uptake, C and N allocation patterns in plants, and root fungal...... ecosystems are capable of taking up organic N as intact glycine both under high irradiance levels and under shaded conditions when photosynthesis is strongly reduced. The allocation of 15N to green leaves of Rubus chamaemorus L. increased with shading, whereas the allocation of 13C to leaves of both...

  15. The solar ultraviolet B radiation protection provided by shading devices with regard to its diffuse component.

    Science.gov (United States)

    Kudish, Avraham I; Harari, Marco; Evseev, Efim G

    2011-10-01

    The composition of the incident solar global ultraviolet B (UVB) radiation with regard to its beam and diffuse radiation fractions is highly relevant with regard to outdoor sun protection. This is especially true with respect to sun protection during leisure-time outdoor sun exposure at the shore and pools, where people tend to escape the sun under shade trees or different types of shading devices, e.g., umbrellas, overhangs, etc., believing they offer protection from the erythemal solar radiation. The degree of sun protection offered by such devices is directly related to the composition of the solar global UVB radiation, i.e., its beam and diffuse fractions. The composition of the incident solar global UVB radiation can be determined by measuring the global UVB (using Solar Light Co. Inc., Model 501A UV-Biometer) and either of its components. The beam component of the UVB radiation was determined by measuring the normal incidence beam radiation using a prototype, tracking instrument consisting of a Solar Light Co. Inc. Model 501A UV-Biometer mounted on an Eppley Solar Tracker Model St-1. The horizontal beam component of the global UVB radiation was calculated from the measured normal incidence using a simple geometric correlation and the diffuse component is determined as the difference between global and horizontal beam radiations. Horizontal and vertical surfaces positioned under a horizontal overhang/sunshade or an umbrella are not fully protected from exposure to solar global UVB radiation. They can receive a significant fraction of the UVB radiation, depending on their location beneath the shading device, the umbrella radius and the albedo (reflectance) of the surrounding ground surface in the case of a vertical surface. Shading devices such as an umbrella or horizontal overhang/shade provide relief from the solar global radiation and do block the solar global UVB radiation to some extent; nevertheless, a significant fraction of the solar global UVB

  16. Assessment of Color Changes in Vita 3D-Master Shade Guide after Sterilization and Disinfection

    Directory of Open Access Journals (Sweden)

    Hossein Dashti

    2017-06-01

    Full Text Available Purpose:Dental shade guides are commonly used for color determination and should be disinfected and sterilized. The purpose of this study was to evaluate the color change of Vita 3D Master shade tabs after disinfection and sterilization. Material and methods:Overall, 98 samples (shade tabs were randomly selected from 14 new, unused Vita 3D sets, including the following shades: 2M1, 3L1.5, 3M1, 3M2, 3M3, 3R1.5 and 4M1. In each set, values of 2, 3 and 4, chroma of 1, 2 and 3 and hue were selected for the comparison of different shades. All tabs were measured using the Vita Easyshade device at baseline. The first group was disinfected with Deconex and the second group was sterilized by autoclaving in a simulated annual application. All the tabs were measured again using the same device. This process was repeated to simulate 2 and 3 years of usage. Statistical analysis was conducted by repeated measures analysis of variance (ANOVA and independent t-test and paired sample t-test. Results:In the disinfected group, we observed significant differences in value and chroma in all periods (p˂0.001. However, hue showed no significant difference after the first year of simulated treatment (p=0.527, though it was significantly different in the second and third simulations (p˂0.001. In the sterilized group, all variables showed a significant difference for each year (p˂0.05. Considering total color difference (ΔE, there was a significant difference between the two groups in the first, second and third simulated years; ΔE increased in the sterilized group more than in the disinfected samples (p˂0.001.  Conclusions:  The color change of shade tabs was significant both after disinfection by a chemical solution and by sterilization through autoclaving. However, although disinfectants may not have a clinically important effect, sterilization should be considered as an interfering factor during color-matching procedure.

  17. A Multirelational Account of Toleration

    DEFF Research Database (Denmark)

    Ferretti, Maria Paola; Lægaard, Sune

    2013-01-01

    Toleration classically denotes a relation between two agents that is characterised by three components: objection, power, and acceptance overriding the objection. Against recent claims that classical toleration is not applicable in liberal democracies and that toleration must therefore either be ...

  18. 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 on re...

  19. 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"

  20. 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

  1. 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

  2. Emotions in "Black and White" or Shades of Gray? How We Think About Emotion Shapes Our Perception and Neural Representation of Emotion.

    Science.gov (United States)

    Satpute, Ajay B; Nook, Erik C; Narayanan, Sandhya; Shu, Jocelyn; Weber, Jochen; Ochsner, Kevin N

    2016-11-01

    The demands of social life often require categorically judging whether someone's continuously varying facial movements express "calm" or "fear," or whether one's fluctuating internal states mean one feels "good" or "bad." In two studies, we asked whether this kind of categorical, "black and white," thinking can shape the perception and neural representation of emotion. Using psychometric and neuroimaging methods, we found that (a) across participants, judging emotions using a categorical, "black and white" scale relative to judging emotions using a continuous, "shades of gray," scale shifted subjective emotion perception thresholds; (b) these shifts corresponded with activity in brain regions previously associated with affective responding (i.e., the amygdala and ventral anterior insula); and (c) connectivity of these regions with the medial prefrontal cortex correlated with the magnitude of categorization-related shifts. These findings suggest that categorical thinking about emotions may actively shape the perception and neural representation of the emotions in question. © The Author(s) 2016.

  3. Color and shade parameters of ultramarine zeolitic pigments synthesized from kaolin waste

    International Nuclear Information System (INIS)

    Menezes, Raquel Aranha de; Paz, Simone Patricia Aranha da; Angelica, Romulo Simoes; Neves, Roberto de Freitas; Pergher, Sibele Berenice Castella

    2014-01-01

    Ultramarine pigments were successful synthesized from zeolite A obtained from kaolin waste. This waste has been used as an excellent source of silicon and aluminum for zeolite synthesis because of its high kaolinite concentrations and low contents of other accessory minerals. The cost is naturally less than the industrialized product. Color additives (Sulfur and Sodium Carbonate) were mixed with different proportions of zeolite A and further calcined for 5 h at 500 °C. They were characterized by XRD and XRF in addition to visual classification by color and shade. These products show colors from blue to green at different shades, both influenced by the amount of additives and cooling rate after calcination. Thus, a different quantity of the same additives in the same zeolitic matrix provides an increase in the color intensity. Cooling rate after calcination induces the color change which is substantially important in the pigments production. (author)

  4. Color and shade parameters of ultramarine zeolitic pigments synthesized from kaolin waste

    Energy Technology Data Exchange (ETDEWEB)

    Menezes, Raquel Aranha de; Paz, Simone Patricia Aranha da; Angelica, Romulo Simoes; Neves, Roberto de Freitas; Pergher, Sibele Berenice Castella, E-mail: raquel_arn@hotmail.com [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Geociencias. Grupo de Mineralogia e Geoquimica Aplicada

    2014-08-15

    Ultramarine pigments were successful synthesized from zeolite A obtained from kaolin waste. This waste has been used as an excellent source of silicon and aluminum for zeolite synthesis because of its high kaolinite concentrations and low contents of other accessory minerals. The cost is naturally less than the industrialized product. Color additives (Sulfur and Sodium Carbonate) were mixed with different proportions of zeolite A and further calcined for 5 h at 500 °C. They were characterized by XRD and XRF in addition to visual classification by color and shade. These products show colors from blue to green at different shades, both influenced by the amount of additives and cooling rate after calcination. Thus, a different quantity of the same additives in the same zeolitic matrix provides an increase in the color intensity. Cooling rate after calcination induces the color change which is substantially important in the pigments production. (author)

  5. Effects of shading and ethephon on carbon assimilates distribution partitioning in fruit limb of greenhouse-grown 'Dajiubao' peach

    International Nuclear Information System (INIS)

    Kong Yun; Wang Shaohui; Yao Yuncong; Ma Chengwei

    2007-01-01

    The distribution of carbon assimilates and the relative sink strength were studied by 14 C labeling in one-year-old fruiting limbs of greenhouse-grown 'Dajiubao' peach (Prunus persica L. Batsch), under 60% shading and 600 mg/L Ethephon treatment. After 10d shading treatment prior to pulsing of 14 CO 2 percent of assimilates translocation into fruit decreased significantly from fed shoot during fruit-ripening stage, but this partitioning patterns was not observed during stone-hardening stage, although less carbon allocated to seed within fruit components (mesocarp, endocarp and seed). The relative sink strength of each organ nearly followed the same variation trend as carbon assimilates distribution under shading treatment. Application of Ethephon to the surface of fruits under shading conditions promoted more carbon into fruits during fruit-ripening stage, with increasing their relative skink strength. (authors)

  6. A new topology to mitigate the effect of shading for small photovoltaic installations in rural sub-Saharan Africa

    International Nuclear Information System (INIS)

    Ubisse, A.; Sebitosi, A.

    2009-01-01

    Many field researchers have in the past grappled with the problems of energy loss and panel damage as a result of shading and staining of PV panels after installation. A number of solutions have been proposed to try and minimize the effects of this problem in the field. The problem with all these solutions is that they address inter-panel connection topologies for very large installations. No particular attention has been paid to the topologies of individual panels. In sub-Saharan Africa most installations are single panel solar home systems and therefore small shading can result in an entire installation being disabled. This paper aims to study the effect of shading and staining on photovoltaic modules and propose a new topology that will reduce the effect of shading on the performance of individual photovoltaic modules.

  7. Physiological aspects of sun and shade leaves of Lithraea molleoides (Vell. Engl. (Anacardiaceae

    Directory of Open Access Journals (Sweden)

    Jaqueline Dias

    2007-01-01

    Full Text Available The aim of this work was to compare the physiological parameters of sun and shade leaves of a specimen of L. molleoides. The higher-positional leaves, classified as sun leaves, presented similar photosynthetic rate, lower chlorophyill contents (a, b and total, same a chlorophyll /b chlrorophyll rate, lower transpiratory rate, same stomatal conductance and intercellular concentration of CO2 as the lower-positional leaves, classified as shade leaves. Nutrient concentration, except for Ca and Mg, was the same for both sun and shade leaves.The physiological parameter responses indicated that although receiving lower light intensity, the shade leaves had the same capacity to grow and develop as the sun leaves.O presente trabalho teve como objetivo avaliar de forma comparativa alguns parâmetros fisiológicos de folhas de sol e de sombra de um espécime de L. molleoides. Esta espécie é conhecida popularmente como aroeira-branca. As folhas da porção superior periférica, denominadas folhas de sol, apresentaram igual taxa fotossintética, menores teores de clorofilas (a, b e totais, mesma razão clorofila a/ clorofila b, menor taxa transpiratória, mesma condutância estomática e concentração intercelular de CO2 em relação às folhas da porção inferior interna, denominadas folhas de sombra. A concentração de nutrientes, excetuando Ca e Mg, foi igual em folhas de sol e de sombra. As respostas dos parâmetros fisiológicos avaliados indicam que as folhas de sombra, apesar de receberem menor intensidade luminosa, têm possibilidade de crescer e se desenvolver com a mesma capacidade das folhas de sol.

  8. Adaptive Fuzzy Logic based MPPT Control for PV System Under Partial Shading Condition

    OpenAIRE

    Choudhury, Subhashree; Rout, Pravat Kumar

    2016-01-01

    Partial shading causes power loss, hotspots and threatens the reliability of the Photovoltaic generation system. Moreover characteristic curves exhibit multiple peaks. Conventional MPPT techniques under this condition often fail to give optimum MPP. Focusing on the afore mentioned problem an attempt has been made to design an Adaptive Takagi-Sugeno Fuzzy Inference System based Fuzzy Logic Control MPPT.The mathematical model of PV array is simulated using in MATLAB/Simulink environment.Various...

  9. Shaded Coffee: A way to Increase Sustainability in Brazilian Organic Coffee plantations

    OpenAIRE

    Moreira, Cassio Franco; De Nadai Fernandes, Elisabete A.; Tagliaferro, Fábio Sileno

    2008-01-01

    Consumption of specialty coffee, mainly organic coffee, increases worldwide following the tendency of consuming social and ecological sustainable products. Brazil is the world largest coffee producer, with an average of 2,300,000 tons of green coffee in the last 5 years. Cultivation of organic coffee and shaded coffee are common in Central America, while in Brazil both conventional and organic coffee are cultivated in the full sun system. The full sun system is criticized due to the lack of b...

  10. Effects of shading on the photosynthetic characteristics and mesophyll cell ultrastructure of summer maize.

    Science.gov (United States)

    Ren, Baizhao; Cui, Haiyan; Camberato, James J; Dong, Shuting; Liu, Peng; Zhao, Bin; Zhang, Jiwang

    2016-08-01

    A field experiment was conducted to study the effects of shading on the photosynthetic characteristics and mesophyll cell ultrastructure of two summer maize hybrids Denghai605 (DH605) and Zhengdan958 (ZD958). The ambient sunlight treatment was used as control (CK) and shading treatments (40 % of ambient sunlight) were applied at different growth stages from silking (R1) to physiological maturity (R6) (S1), from the sixth leaf stage (V6) to R1 (S2), and from seeding to R6 (S3), respectively. The net photosynthetic rate (P n) was significantly decreased after shading. The greatest reduction of P n was found at S3 treatment, followed by S1 and S2 treatments. P n of S3 was decreased by 59 and 48 % for DH605, and 39 and 43 % for ZD958 at tasseling and milk-ripe stages, respectively, compared to that of CK. Additionally, leaf area index (LAI) and chlorophyll content decreased after shading. In terms of mesophyll cell ultrastructure, chloroplast configuration of mesophyll cells dispersed, and part of chloroplast swelled and became circular. Meanwhile, the major characteristics of chloroplasts showed poorly developed thylakoid structure at the early growth stage, blurry lamellar structure, loose grana, and a large gap between slices and warping granum. Then, plasmolysis occurred in mesophyll cells and the endomembrane system was destroyed, which resulted in the dissolution of cell membrane, karyotheca, mitochondria, and some membrane structures. The damaged mesophyll cell ultrastructure led to the decrease of photosynthetic capacity, and thus resulted in significant yield reduction by 45, 11, and 84 % in S1, S2, and S3 treatments, respectively, compared to that of CK.

  11. Photosynthetic behavior, growth and essential oil production of Melissa officinalis L. cultivated under colored shade nets

    OpenAIRE

    Graziele C Oliveira; Willyam L Vieira; Suzana C Bertolli; Ana Claudia Pacheco

    2016-01-01

    The modulation of light is of importance during cultivation of medicinal plants to obtain desirable morphological and physiological changes associated with the maximum production of active principles. This study aimed to evaluate the effect of the light spectrum transmitted by colored shade nets on growth, essential oil production and photosynthetic behavior in plants of lemon balm (Melissa officinalis L.) Plants were cultivated in pots for 4-mo under black, red, and blue nets with 50% shadin...

  12. Tracing of shading effect on underachieving SPV cell of an SPV grid using wireless sensor network

    OpenAIRE

    Kaundal, Vivek; Mondal, Amit Kumar; Sharma, Paawan; Bansal, Kamal

    2015-01-01

    The environmental and economic merits of converting solar energy into electricity via photovoltaic cells have led to its enormous growth in this sector. Besides material and design parameters, there are many other factors which locally affect Photovoltaic cell like partial shading, humidity, dust, bird droppings, air velocity etc. However, the effect due to a single solar photo voltaic cell being connected to a serial or parallel network (to form a grid) has never been deliberated extensively...

  13. Changes to Glazed Dental Ceramic Shade, Roughness, and Microhardness after Bleaching and Simulated Brushing.

    Science.gov (United States)

    Rodrigues, Carlos Roberto Teixeira; Turssi, Cecilia Pedroso; Amaral, Flávia Lucisano Botelho; Basting, Roberta Tarkany; França, Fabiana Mantovani Gomes

    2017-09-05

    To evaluate shade stability, surface roughness, microhardness, and compressive strength of a glazed feldspathic ceramic subjected to bleaching and simulated brushing. Eighty-eight glazed feldspathic ceramic specimens were made from microparticulate leucite and divided into eight groups (n = 10). The whitening products used were: Opalescence Trèswhite Supreme (Ultradent), Opalescence®\\ PF 15% (Ultradent), and Oral-B 3D White Whitestrips. All substances for whitening were used for 4 hours/day for a period of 14 days; the control group was not bleached. Next, half of the specimens were individually brushed. Microhardness and surface roughness data were subjected to three-way ANOVA and Tukey test. The diametrical tensile strength data were subjected to two-way ANOVA. The shade change data were analyzed using Kruskal-Wallis, Mann-Whitney, and the Student-Newman-Keuls test. The significance level was set at 5%. Glazed feldspathic ceramic surface microhardness was significantly affected by bleaching agents (p = 0.007). Initially, glazed ceramic microhardness was significantly higher than that observed after contact with the bleaching agents, whether or not brushing was performed. The specimens submitted to bleaching in preloaded trays presented lower surface roughness values after brushing (p = 0.037). The surface roughness was significantly lower in the brushed specimens (p = 0.044). The diametrical tensile strength was not significantly affected by the application of bleaching agents (p = 0.563) or by brushing (p = 0.477). When the specimens were brushed, however, shade change was significantly influenced by the bleaching agent used (p = 0.041). Bleaching agents associated with brushing cycles can alter surface properties and shade stability of glazed feldspathic ceramics, though such findings may not reflect the performance of unglazed feldspathic ceramics. © 2017 by the American College of Prosthodontists.

  14. Simulation of tree shade impacts on residential energy use for space conditioning in Sacramento

    Science.gov (United States)

    Simpson, J. R.; McPherson, E. G.

    Tree shade reduces summer air conditioning demand and increases winter heating load by intercepting solar energy that would otherwise heat the shaded structure. We evaluate the magnitude of these effects here for 254 residential properties participating in a utility sponsored tree planting program in Sacramento, California. Tree and building characteristics and typical weather data are used to model hourly shading and energy used for space conditioning for each building for a period of one year. There were an average of 3.1 program trees per property which reduced annual and peak (8 h average from 1 to 9 p.m. Pacific Daylight Time) cooling energy use 153 kWh (7.1%) and 0.08 kW (2.3%) per tree, respectively. Annual heating load increased 0.85 GJ (0.80 MBtu, 1.9%) per tree. Changes in cooling load were smaller, but percentage changes larger, for newer buildings. Averaged over all homes, annual cooling savings of 15.25 per tree were reduced by a heating penalty of 5.25 per tree, for net savings of 10.00 per tree from shade. We estimate an annual cooling penalty of 2.80 per tree and heating savings of 6.80 per tree from reduced wind speed, for a net savings of 4.00 per tree, and total annual savings of 14.00 per tree (43.00 per property). Results are found to be consistent with previous simulations and the limited measurements available.

  15. State, religion and toleration

    DEFF Research Database (Denmark)

    Huggler, Jørgen

    2009-01-01

    Contribution to Religion and State - From separation to cooperation? Legal-philosophical reflections for a de-secularized world. (IVR Cracow Special Workshop). Eds. Bart. C. Labuschagne & Ari M. Solon. Abstract: Toleration is indeed a complex phenomenon. A discussion of the concept will have...... to underline not only the broadmindedness and liberty of individuals or of groups, but also the relevant distinctions and arguments in political philosophy, epistemology, philosophy of religion and philosophical anthropology and their connection with educational issues. Through a discussion of these relations......, the essay argues three theses: (1) Toleration is not reducible to an ethics of spiritual freedom. (2) Toleration is not neutral to fanatism. (3) Toleration involves esteem for the person....

  16. Maximum power point tracking for PV systems under partial shading conditions using current sweeping

    International Nuclear Information System (INIS)

    Tsang, K.M.; Chan, W.L.

    2015-01-01

    Highlights: • A novel approach for tracking the maximum power point of photovoltaic systems. • Able to handle both the uniform insolation and partial shading conditions. • Maximum power point tracking based on current sweeping. - Abstract: Partial shading on photovoltaic (PV) arrays causes multiple peaks on the output power–voltage characteristic curve and local searching technique such as perturb and observe (P&O) method could easily fail in searching for the global maximum. Moreover, existing global searching techniques are still not very satisfactory in terms of speed and implementation complexity. In this paper, a fast global maximum power point (MPPT) tracking method which is using current sweeping for photovoltaic arrays under partial shading conditions is proposed. Unlike conventional approach, the proposed method is current based rather than voltage based. The initial maximum power point will be derived based on a current sweeping test and the maximum power point can be enhanced by a finer local search. The speed of the global search is mainly governed by the apparent time constant of the PV array and the generation of a fast current sweeping test. The fast current sweeping test can easily be realized by a DC/DC boost converter with a very fast current control loop. Experimental results are included to demonstrate the effectiveness of the proposed global searching scheme

  17. Shaded seafloor relief, backscatter strength, and surficial geology; German Bank, Scotian Shelf, offshore Nova Scotia

    Science.gov (United States)

    Todd, B.J.; Valentine, Page C.

    2010-01-01

    This map is part of a three-map series of German Bank, located on the Scotian Shelf off southern Nova Scotia.  This map is the product of a number of surveys (1997-2003) that used a multibeam sonar system to map 5321 km2 of the seafloor.  Other surveys collected geological data for scientific interpretation.  This map sheet shows the seafloor topography of German Bank in shaded-relief view and seafloor depth (coded by colour) at a scale of 1:1000,000.  Topographic contours generated from the multibeam data are shown (in white) on the colour-coded multibeam topography at a depth interval of 20 m.  Bathymetic contours (in blue) outside the multibeam survey area, presented at a depth interval of 10 m, are from the Natural Resource Map series (Canadian Hydrographic Service, 1967, 1971a, 1971b, 1972). Sheet 2 shows coloured backscatter strength in shaded-relief view.  Sheet 3 shows seafloor topography in shaded-relief view with colour-coded surficial geological units.

  18. Shade and flow effects on ammonia retention in macrophyte-rich streams: implications for water quality

    International Nuclear Information System (INIS)

    Wilcock, Robert J.; Scarsbrook, Mike R.; Cooke, James G.; Costley, Kerry J.; Nagels, John W.

    2004-01-01

    Controlled releases of NH 4 -N and conservative tracers (Br - and Cl - ) to five reaches of four streams with contrasting macrophyte communities have shown differing retentions, largely as a result of the way plants interact with stream flow and velocity. First-order constants (k) were 1.0-4.8 d -1 and retention of NH 4 -N was 6-71% of amounts added to each reach. Distance travelled before a 50% reduction in concentration was achieved were 40-450 m in three streams under low-flow conditions, and 2400-3800 m at higher flows. Retention (%) of NH 4 -N can be approximated by a simple function of travel time and k, highlighting the importance of the relationship between macrophytes and stream velocity on nutrient processing. This finding has significant management implications, particularly with respect to restoration of riparian shade. Small streams with predominantly marginal emergent plants are likely to have improved retention of NH 4 -N as a result of shading or other means of reducing plant biomass. Streams dominated by submerged macrophytes will have impaired NH 4 -N retention if plant biomass is reduced because of reduced contact times between NH 4 -N molecules and reactive sites. In these conditions water resource managers should utilise riparian shading in concert with unshaded vegetated reaches to achieve a balance between enhanced in-stream habitat and nutrient processing capacity

  19. Comparative study on growth performance of two shade trees in tea agroforestry system.

    Science.gov (United States)

    Kalita, Rinku Moni; Das, Ashesh Kumar; Nath, Arun Jyoti

    2014-07-01

    An attempt was made to study the stem growth of two native dominant shade tree species in terms of annual girth increment in three dominant girth size categories for two years in tea agroforestry system of Barak Valley, Assam. Fifty two sampling plots of 0.1 ha size were established and all trees exceeding 10 cm girth over bark at breast height (1.37 m) were uniquely identified, tagged, and annually measured for girth increment, using metal tape during December 2010-12. Albizia lebbeck and A. odoratissima were dominant shade tree species registering 82% of appearance of the individuals studied. The girth class was categorized into six different categories where 30-50 cm, 50-70 cm and 70-90 cm were dominating girth classes and selected for increment study. Mean annual girth increment ranged from 1.41 cm in Albizia odoratissima (50-70 cm girth class) to 2.97 cm in Albizia lebbeck (70-90 cm girth class) for the first year and 1.70 cm in Albizia odoratissima (50-70 cm girth class) to 3.09 cm in Albizia lebbeck (70-90 cm girth class) for the second year. Albizia lebbeck exhibited better growth in all prominent girth classes as compared to Albizia odoratissima during the observation period. The two shade tree species showed similar trend of growth in both the years of observation and significant difference in girth increment.

  20. Schoolyard Shade and Sun Exposure: Assessment of Personal Monitoring During Children's Physical Activity.

    Science.gov (United States)

    Vanos, Jennifer K; McKercher, Grant R; Naughton, Kylie; Lochbaum, Marc

    2017-07-01

    Childhood exposure to ultraviolet radiation (UVR) is a major risk factor for the development of melanoma later in life. However, it is challenging to accurately determine personal outdoor exposure to UVR, specifically erythemally weighted UVR (UV E ry ), due to technological constraints, variable time-activity patterns, and the influence of outdoor environmental design. To address this challenge, this study utilized mobile and stationary techniques to examine the UV E ry exposures of 14 children in a schoolyard in Lubbock, TX, in spring 2016. The aims of the study were to examine the influence of artificial shade on personal UV E ry exposures and to assess full sun exposure ratios (ERs) within the same playground microenvironment. On average, personal wrist dosimeters worn during play in the sun measured 18% of the total onsite UV E ry measured by a stationary UV pyranometer. Shade was found to significantly reduce the personal UV E ry exposures by 55%, UVB 280-315 nm exposures by 91%, and the overall solar radiation by 84%. Substantial benefits can be garnered through focused design of children's recreational space to utilize shade-both natural and artificial-to reduce UVR exposures during play, and to extend safe outdoor stays. Finally, although the wrist is a practical location for a dosimeter, it often underestimates full exposures, particularly during physical activity. © 2017 The American Society of Photobiology.

  1. Flectofold—a biomimetic compliant shading device for complex free form facades

    Science.gov (United States)

    Körner, A.; Born, L.; Mader, A.; Sachse, R.; Saffarian, S.; Westermeier, A. S.; Poppinga, S.; Bischoff, M.; Gresser, G. T.; Milwich, M.; Speck, T.; Knippers, J.

    2018-01-01

    Smart and adaptive outer façade shading systems are of high interest in modern architecture. For long lasting and reliable systems, the abandonment of hinges which often fail due to mechanical wear during repetitive use is of particular importance. Drawing inspiration from the hinge-less motion of the underwater snap-trap of the carnivorous waterwheel plant (Aldrovanda vesiculosa), the compliant façade shading device Flectofold was developed. Based on computational simulations of the biological role-model’s elastic and reversible motion, the actuation principle of the plant can be identified. The enclosed geometric motion principle is abstracted into a simplified curved-line folding geometry with distinct flexible hinge-zones. The kinematic behaviour is translated into a quantitative kinetic model, using finite element simulation which allows the detailed analyses of the influence of geometric parameters such as curved-fold line radius and various pneumatically driven actuation principles on the motion behaviour, stress concentrations within the hinge-zones, and actuation forces. The information regarding geometric relations and material gradients gained from those computational models are then used to develop novel material combinations for glass fibre reinforced plastics which enabled the fabrication of physical prototypes of the compliant façade shading device Flectofold.

  2. Vertex shading of the three-dimensional model based on ray-tracing algorithm

    Science.gov (United States)

    Hu, Xiaoming; Sang, Xinzhu; Xing, Shujun; Yan, Binbin; Wang, Kuiru; Dou, Wenhua; Xiao, Liquan

    2016-10-01

    Ray Tracing Algorithm is one of the research hotspots in Photorealistic Graphics. It is an important light and shadow technology in many industries with the three-dimensional (3D) structure, such as aerospace, game, video and so on. Unlike the traditional method of pixel shading based on ray tracing, a novel ray tracing algorithm is presented to color and render vertices of the 3D model directly. Rendering results are related to the degree of subdivision of the 3D model. A good light and shade effect is achieved by realizing the quad-tree data structure to get adaptive subdivision of a triangle according to the brightness difference of its vertices. The uniform grid algorithm is adopted to improve the rendering efficiency. Besides, the rendering time is independent of the screen resolution. In theory, as long as the subdivision of a model is adequate, cool effects as the same as the way of pixel shading will be obtained. Our practical application can be compromised between the efficiency and the effectiveness.

  3. Analysis of Shade Matching in Natural Dentitions Using Intraoral Digital Spectrophotometer in LED and Filtered LED Light Sources.

    Science.gov (United States)

    Chitrarsu, Vijai Krishnan; Chidambaranathan, Ahila Singaravel; Balasubramaniam, Muthukumar

    2017-10-31

    To evaluate the shade matching capabilities in natural dentitions using Vita Toothguide 3D-Master and an intraoral digital spectrophotometer (Vita Easyshade Advance 4.0) in various light sources. Participants between 20 and 40 years old with natural, unrestored right maxillary central incisors, no history of bleaching, orthodontic treatment, or malocclusion and no rotations were included. According to their shades, subjects were randomly selected and grouped into A1, A2, and A3. A total of 100 participants (50 male and 50 female) in each group were chosen for this study. Shade selection was made between 10 am and 2 pm for all light sources. The same examiner selected the shade of natural teeth with Vita Toothguide 3D-Master under natural light within 2 minutes. Once the Vita Toothguide 3D-Masterwas matched with the maxillary right central incisor, the L*, a*, and b* values, chroma, and hue were recorded with Vita Easyshade Advance 4.0 by placing it on the shade tab under the same light source. The values were statistically analyzed using one-way ANOVA and Tukey's HSD post hoc test with SPSS v22.0 software. The mean ∆E* ab values for shades A1, A2, and A3 for groups 1, 2, and 3 were statistically significantly different from each other (p spectrophotometer showed statistically significant differences in shade matching compared to Vita Toothguide 3D-Master. Incandescent light showed more accurate shade matching than the filtered LED, LED, and daylight. © 2017 by the American College of Prosthodontists.

  4. Shade-grown coffee in Puerto Rico: Opportunities to preserve biodiversity while reinvigorating a struggling agricultural commodity

    Science.gov (United States)

    Borkhataria, R.; Collazo, J.A.; Groom, Martha J.; Jordan-Garcia, A.

    2012-01-01

    Shade-grown coffee contributes to biodiversity conservation and has many ecological benefits. We reviewed historical trends in coffee production and interviewed 100 coffee growers in 1999 to determine current management practices and attitudes toward the cultivation of sun and shade coffee in Puerto Rico. We discuss the outlook for the coffee industry in the 21st century and implications for biodiversity conservation, hoping lessons from Puerto Rico will apply to the international coffee industry. Throughout the 20th century, government intervention, including subsidies and technical assistance, supported coffee farming in Puerto Rico. In an effort to modernize coffee production and increase yields, the conversion from shade to sun coffee plantations was encouraged. Despite government support, the amount of land devoted to this once dominant agricultural commodity declined markedly between 1982 and 2007 (84%), due to labor shortages, low income, and catastrophic hurricanes. We found that a return to shaded plantations would be embraced by most farmers. Growers of shaded coffee were generally happier with their cultivation practices (89.3% satisfied) than growers of sun coffee (60.9% satisfied), valued biodiversity, and were willing to cultivate coffee under shade if given similar incentives to those received for farming sun coffee. The future of the coffee industry in Puerto Rico may depend on government programs that capitalize upon emerging markets for sustainably produced, shade-grown coffee. We conclude that where governments have close ties to the coffee industry, they should strive to wed economic development with the conservation of biodiversity and associated ecological services by providing support and incentives for the production of shade coffee. ?? 2011 Elsevier B.V.

  5. Seed germination of Pinus koraiensis Siebold and Zucc. in response to light regimes caused by shading and seed positions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, M.; Zhu, J.; Yan, Q.

    2012-07-01

    Pinus koraiensis Siebold and Zucc. (Korean pine), the dominant tree species in the mixed broadleaved Korean pine forests (regional climax), is severely restricted by its regeneration failure. To determine the effects of light regimes on P. koraiensis regeneration, the seed germination process was examined in shade houses and forest stands (before and after leaf expansion) with various light levels created by shading and seed positions. Despite the large size of P. koraiensis seeds (500-600 mg), both light intensity and quality significantly affected the germination percentage in both shade houses and forests. Substantial changes in light intensity and quality led the majority of seeds (80%) to germinate in leafless forests and shade houses, while only a minority ({<=}20%) germinated after leaf expansion in the forests. Moreover, seed germination in shade houses and leafless forests exhibited similar patterns; they consistently reached a 70% shading degree, which was optimal for the seed germination of P. koraiensis on topsoil. Seed positioning significantly affected germination for each shading degree, especially when litter and soil coverings drastically inhibited germination. In conclusion, (1) when seeds were not stressed by temperature and moisture, light irradiance played a critical role in the seed germination of P. koraiensis; (2) seed positioning, in relation to alterations in light intensity and quality, affected the germination of P. koraiensis; (3) a shade house experiment using neutral cloth provided an applicable and controllable way to monitor the P. koraiensis seed germination in early spring before leaf expansion. The light requirement for the germination of P. koraiensis played a key role in the regeneration of P. koraiensis throughout the temperate secondary forests. (Author) 41 refs.

  6. NPC Based Design Optimization for a Net Zero Office Building in Hot Climates with PV Panels as Shading Device

    Directory of Open Access Journals (Sweden)

    Muhammad Zubair

    2018-05-01

    Full Text Available Hot areas of the world receive a high amount of solar radiation. As a result, buildings in those areas consume more energy to maintain a comfortable climate for their inhabitants. In an effort to design net-zero energy building in hot climates, PV possesses the unique advantage of generating electrical energy while protecting the building from solar irradiance. In this work, to form a net-zero energy building (NZEB, renewable resources such as solar and wind available onsite for an existing building have been analyzed in a hot climate location. PV and wind turbines in various configurations are studied to form a NZEB, where PV-only systems offer better performance than Hybrid PV Wind systems, based on net present cost (NPC. The self-shading losses in PV placed on rooftop areas are analyzed by placing parallel arrays of PV modules at various distances in between them. The effect on building cooling load by rooftop PV panels as shading devices is investigated. Furthermore, self-shading losses of PV are compared by the savings in cooling loads using PV as shading. In the case study, 12.3% saving in the cooling load of the building is observed when the building rooftop is completed shaded by PV panels; annual cooling load decreased from 3.417 GWh to 2.996 GWh, while only 1.04% shaded losses are observed for fully shaded (FS buildings compared to those with no shading (NS, as PV generation decreases from 594.39 kWh/m2 to 588.21 kWh/m2. The net present cost of the project has been decreased from US$4.77 million to US$4.41 million by simply covering the rooftop completely with PV panels, for a net-zero energy building.

  7. A Theory of Tolerance

    OpenAIRE

    Corneo, Giacomo; Jeanne, Olivier

    2006-01-01

    We develop an economic theory of tolerance where styles of behaviour are invested with symbolic value. Value systems are endogenous and taught by parents to their children. In conjunction with actual behaviour, value systems determine the esteem enjoyed by individuals. Intolerant individuals have all symbolic value invested in a single style of behaviour, whereas tolerant people have diversified values. The proposed model identifies a link between the unpredictability of children's lifestyles...

  8. Genetic polymorphisms in varied environments.

    Science.gov (United States)

    Powell, J R

    1971-12-03

    Thirteen experimenital populationis of Drosophila willistoni were maintained in cages, in some of which the environments were relatively constant and in others varied. After 45 weeks, the populations were assayed by gel electrophoresis for polymorphisms at 22 protein loci. The average heterozygosity per individual and the average unmber of alleles per locus were higher in populations maintained in heterogeneous environments than in populations in more constant enviroments.

  9. Effect of shade on Arabica coffee berry disease development: Toward an agroforestry system to reduce disease impact.

    Science.gov (United States)

    Mouen Bedimo, J A; Njiayouom, I; Bieysse, D; Ndoumbè Nkeng, M; Cilas, C; Nottéghem, J L

    2008-12-01

    Coffee berry disease (CBD), caused by Colletotrichum kahawae, is a major constraint for Arabica coffee cultivation in Africa. The disease is specific to green berries and can lead to 60% harvest losses. In Cameroon, mixed cropping systems of coffee with other crops, such as fruit trees, are very widespread agricultural practices. Fruit trees are commonly planted at random on coffee farms, providing a heterogeneous shading pattern for coffee trees growing underneath. Based on a recent study of CBD, it is known that those plants can reduce disease incidence. To assess the specific effect of shade, in situ and in vitro disease development was compared between coffee trees shaded artificially by a net and trees located in full sunlight. In the field, assessments confirmed a reduction in CBD on trees grown under shade compared with those grown in full sunlight. Artificial inoculations in the laboratory showed that shade did not have any effect on the intrinsic susceptibility of coffee berries to CBD. Coffee shading mainly acts on environmental parameters in limiting disease incidence. In addition to reducing yield losses, agroforestry system may also be helpful in reducing chemical control of the disease and in diversifying coffee growers' incomes.

  10. The effect of different shades of specific luting agents and IPS empress ceramic thickness on overall color.

    Science.gov (United States)

    Terzioğlu, Hakan; Yilmaz, Burak; Yurdukoru, Bengul

    2009-10-01

    The color stability of both porcelain and luting materials is very important for the esthetics of laminate veneers and all-ceramic crowns. The purpose of this study was to determine the effect of different shades of resin-based luting cement and the thickness of IPS Empress ceramics on the final color of the restorations. Resin-based dual-polymerized composite cement in two different shades (RelyX ARC) and ceramic disks of different thicknesses were selected for the study. Forty specimens (ten each of four different thicknesses: 0.5 mm, 1 mm, 2 mm, and 3 mm) were used for the evaluation. Initial specimen color parameters were determined in a Commission Internationale de l'Eclairage L*a*b* color order system with a colorimeter. Two different shades of the cement were prepared as polymerized layers and applied to one face of the specimens in order. Color changes were calculated between baseline color measurements and measurements after cementation. Color difference data were analyzed statistically. All specimens showed a significant color shift (DE > 3.7) after cementation regardless of the cement shade. However, the differences in the cement shade did not significantly affect the final color of the ceramic specimens for any thickness, and color shifts were not perceivable between the different shades of cement. (Int J Periodontics Restorative Dent 2009;29:499-505.).

  11. Re-Defining Traditional Bazaar Areas and Shade Structures Via Parametric Design Methods

    Directory of Open Access Journals (Sweden)

    Ahmet Emre Dinçer

    2017-12-01

    Full Text Available For the continuation of life, people created various equipment and goods. To create mutual benefits, they’ve exchanged the overpruduced items with different products. This has begun the shopping act. By the increased amount of transactions, a need of defined area for shopping have arisen.  For a temporary time, trading areas have been developed at different locations at a certain period. In the course of time, beside trading, these areas served as socio-cultural spaces where the human relations were established. Moreover, demand of being able to immediately access to needed goods have emerged. This situation made having a permanent trading area essential. Therefore, enclosed and permanent trade areas from bazaar, inn, bedesten, arasta to shopping malls have emerged. Next to all these trading areas, traditional bazaar areas keep being established. Nowadays, there is a need of providing some determined comfort conditions to the users for these street alley bazaars. Decreasing the effect of unfavorable weather conditions and providing supportive certain services and units (like WCs, security, cleanliness, etc. are some of them. As a fundamental solution, without disengaging the user relations with the outside, shade structures are generally provided. Shade structures can support cleaning and similar jobs by gathering and using rainwater besides its purpose of protecting the user from bad weather conditions. Application examples of these systems are gradually increasing. However, it is necessary to develop new approaches, in order to stop these proposed shade structures, become prototypes and to adapt the proposal to its environment and to increase diversity. In this study, a convenient shade structure and its alternatives, which are adapted to environmental conditions, were designed to create a sample model for other bazaar areas. In models, basically, folding design approaches were pursued. For production of these shade structure models

  12. Varying Constants, Gravitation and Cosmology

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Uzan

    2011-03-01

    Full Text Available Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free fall. Thus, it is of utmost importance for our understanding of gravity and of the domain of validity of general relativity to test for their constancy. We detail the relations between the constants, the tests of the local position invariance and of the universality of free fall. We then review the main experimental and observational constraints that have been obtained from atomic clocks, the Oklo phenomenon, solar system observations, meteorite dating, quasar absorption spectra, stellar physics, pulsar timing, the cosmic microwave background and big bang nucleosynthesis. At each step we describe the basics of each system, its dependence with respect to the constants, the known systematic effects and the most recent constraints that have been obtained. We then describe the main theoretical frameworks in which the low-energy constants may actually be varying and we focus on the unification mechanisms and the relations between the variation of different constants. To finish, we discuss the more speculative possibility of understanding their numerical values and the apparent fine-tuning that they confront us with.

  13. Effects of partial shading conditions on maximum power points and mismatch losses in silicon-based photovoltaic power generators

    Energy Technology Data Exchange (ETDEWEB)

    Maki, A.

    2013-11-01

    Photovoltaic (PV) power generators can be used for converting the energy of solar radiation directly into electrical energy without any moving parts. The operation of the generators is highly affected by operating conditions, most importantly irradiances and temperatures of PV cells. PV power generators are prone to electrical losses if the operating conditions are non-uniform such as in a case where part of the modules of a generator are shaded while the rest are receiving the global solar radiation. These conditions are called partial shading conditions and they have been recognized as a major cause of energy losses in PV power generators. In this thesis, the operation of silicon-based PV power generators under partial shading conditions is studied using Matlab Simulink simulation model. The operation of the model has been verified by measurements of electrical characteristics of a PV module under several different operating conditions and also under partial shading conditions. A systematic approach to study the effects of partial shading conditions has been developed and used. In addition to the systematic approach, a vast amount of data measured from the Tampere University of Technology (TUT) Solar Photovoltaic Power Station Research Plant are analyzed and used as input for the simulation model to study operation of PV power generators under actual operating conditions. Partial shading conditions have severe effects on the electrical characteristics of PV power generators and can cause multiple maximum power points (MPPs) to the power-voltage curve of the generators. In most cases, partial shading conditions lead to the occurrence of multiple MPPs, but also only one MPP can be present despite of partial shading. Reasons for this phenomenon are presented and analyzed in this thesis. Because of multiple MPPs, a considerable amount of available electrical energy may be lost when the generator is operating at a local MPP with low power instead of the global MPP. In

  14. Escaping the tolerance trap

    International Nuclear Information System (INIS)

    Hammoudeh, S.; Madan, V.

    1994-01-01

    In order to examine the implications of the weakening of OPEC's responsiveness in adjusting its production levels, this paper explicitly incorporates rigidity in the quantity adjustment mechanism, thereby extending previous research which assumed smooth quantity adjustments. The rigidity is manifested in a tolerance range for the discrepancy between the declared target price and that of the market. This environment gives rise to a 'tolerance trap' which impedes the convergence process and inevitably brings the market to a standstill before its reaches the targeted price and revenue objectives. OPEC's reaction to the standstill has important implications for the achievement of the target-based equilibrium and for the potential collapse of the market price. This paper examines OPEC's policy options in the tolerance trap and reveals that the optional policy in order to break this impasse and move closer to the equilibrium point is gradually to reduce output and not to flood the market. (Author)

  15. Effect of Intra- and Interspecific Competition on the Performance of Native and Invasive Species of Impatiens under Varying Levels of Shade and Moisture

    Czech Academy of Sciences Publication Activity Database

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

    2013-01-01

    Roč. 8, č. 5 (2013), e62842 E-ISSN 1932-6203 R&D Projects: GA ČR GA206/09/0563; GA ČR GA206/07/0668 Institutional support: RVO:67985939 Keywords : phenotypic plasticity * traits * plant invasions Subject RIV: EF - Botanics Impact factor: 3.534, year: 2013

  16. Weighted approximation with varying weight

    CERN Document Server

    Totik, Vilmos

    1994-01-01

    A new construction is given for approximating a logarithmic potential by a discrete one. This yields a new approach to approximation with weighted polynomials of the form w"n"(" "= uppercase)P"n"(" "= uppercase). The new technique settles several open problems, and it leads to a simple proof for the strong asymptotics on some L p(uppercase) extremal problems on the real line with exponential weights, which, for the case p=2, are equivalent to power- type asymptotics for the leading coefficients of the corresponding orthogonal polynomials. The method is also modified toyield (in a sense) uniformly good approximation on the whole support. This allows one to deduce strong asymptotics in some L p(uppercase) extremal problems with varying weights. Applications are given, relating to fast decreasing polynomials, asymptotic behavior of orthogonal polynomials and multipoint Pade approximation. The approach is potential-theoretic, but the text is self-contained.

  17. Estrelas variáveis

    OpenAIRE

    Viana, Sérgio Manuel de Oliveira

    2001-01-01

    A observação do céu nocturno é uma prática que vem da Antiguidade. Desde então e durante muito tempo pensou-se que as estrelas mantinham o brilho constante. Assim foi até ao século XVI, quando David Fabricius observou uma estrela cujo brilho variava periodicamente. Dois séculos mais tarde, Jonh Goodricke descobriu uma segunda estrela e com o desenvolvimento de instrumentos de observação este conjunto foi muito alargado e hoje inclui o Sol.A variação do brilho das estrelas variáveis permite d...

  18. Inequality, Tolerance, and Growth

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequality...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

  19. Inequality, Tolerance, and Growth

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    2004-01-01

    This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequality...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

  20. Congestion control for vehicular delay tolerant network routing protocols

    OpenAIRE

    Oham, Chuka Finbars

    2014-01-01

    The Vehicular Delay Tolerant Network (VDTN) is a special and challenging type of the Delay Tolerant Network because of its high mobility, frequent disconnections and nodal congestion features. These challenging features make it prone to congestion which leads to a considerable amount of message drops in the network. To minimize the impact of congestion in the network, we designed and implemented the Congestion Aware Spray and Wait (CASaW) routing protocol. We varied the buffer sizes of the no...