Science.gov

Sample records for shades fields

  1. Generalized shading analysis for paraboloidal collector fields

    NASA Technical Reports Server (NTRS)

    Osborn, D. B.

    1980-01-01

    This paper presents the development and results of a generalized shading analysis for a field of point-focus parabolic dish concentrators. Shading of one concentrator by another with attendant loss of energy is a function of the position of the sun and the relative locations of the concentrators within the field. A method is presented for determining the annualized energy loss which includes a trade-off of system life-cycle energy as a function of concentrator spacing and field geometric layout. System energy output is computed on an annualized basis, employing 15 minute-increment environmental data tapes for the year 1976 at Barstow, California. For a land cost of $5000 per acre, lowest system energy cost occurs at about a 25 percent packing fraction (concentrator area/land area) for a typical 1-MWe dish-Stirling solar thermal power plant. Basic equations are given for computing the shading and concomitant energy loss as a function of concentrator center-to-center spacing, field layout site location.

  2. Generalized shading analysis for paraboloidal collector fields

    NASA Technical Reports Server (NTRS)

    Osborn, D. B.

    1980-01-01

    This paper presents the development and results of a generalized shading analysis for a field of point-focus parabolic dish concentrators. Shading of one concentrator by another with attendant loss of energy is a function of the position of the sun and the relative locations of the concentrators within the field. A method is presented for determining the annualized energy loss which includes a trade-off of system life-cycle energy as a function of concentrator spacing and field geometric layout. System energy output is computed on an annualized basis, employing 15 minute-increment environmental data tapes for the year 1976 at Barstow, California. For a land cost of $5000 per acre, lowest system energy cost occurs at about a 25 percent packing fraction (concentrator area/land area) for a typical 1-MWe dish-Stirling solar thermal power plant. Basic equations are given for computing the shading and concomitant energy loss as a function of concentrator center-to-center spacing, field layout site location.

  3. A field measure of the shade fraction

    NASA Technical Reports Server (NTRS)

    Gillespie, Alan R.; Smith, Milton O.; Sabol, Donald E.

    1992-01-01

    'Shade' has a technical definition peculiar to linear spectral mixture analysis of imaging spectrometer data: it is the reduction in radiance from a surface due to lighting conditions and geometry, and includes topographic shading described by photometric functions as well as shadowing at all scales. 'Shade' is an important constituent of nearly all remotely sensed images, and is one endmember resolved in spectral mixture analysis, where it is represented as a fraction of the measured radiance and a characteristic spectrum. This spectrum is typically the null vector, provided the data have been corrected for atmospheric and instrument effects: i.e., 'shade' is the radiance from an ideal black surface. In topographic shading, irradiance is reduced - typically in proportion to cos(i), where i (incidence angle) is the angle between the sun and the local surface normal vectors. Therefore, the radiance is lowered by a multiplicative factor. Shadowing occurs when i is greater than 90 deg, or when sunlight is blocked by adjacent high terrain; the only irradiance is down-welling skylight and bounce light from adjacent terrain. In spectral mixture analysis, 'shade' is regarded as an additive term. In this regard, it is an accurate description of the proportion of a scene that consists of ideal shadows ('checkerboard mixing'); however, 'shade' represents the multiplicative cos(i) factor as well, as here it should be interpreted as the proportion of shadow that would darken the scene an equivalent amount. In either case, the 'shade' fraction is lessened by adjacency effects, because the scene has a non-zero reflectivity instead of the ideal black surface generally assumed.

  4. Sun and Shade Leaves: Some Field Investigations.

    ERIC Educational Resources Information Center

    Tomley, David

    1983-01-01

    Several simple experiments illustrating how the light regime affects the final form of dog's mercury (Mercurialis perennis) are provided. These experiments, which can also be done with other plants, focus on differences in the anatomy, morphology, and physiology of sun and shade leaves. (JN)

  5. Modeled riparian stream shading: Agreement with field measurements and sensitivity to riparian conditions

    NASA Astrophysics Data System (ADS)

    Li, Guoyuan; Jackson, C. Rhett; Kraseski, Kristin A.

    2012-03-01

    SummaryShading by riparian vegetation and streambanks reduces incident solar radiation on channels, and accurate estimation of riparian shading through the sun's daily arc is a critical aspect of water temperature and dissolved oxygen modeling. However, riparian trees exhibit complex shapes, often leaning and growing branches preferentially over channels to utilize the light resource. As a result, riparian vegetation cast complex shadows with significant variability at the scale of meters. Water quality models necessarily simplify factors affecting shading at the expense of accuracy. All models must make simplifying assumptions about tree geometry. Reach-based models must average channel azimuth and riparian conditions over each reach, and GIS models must also accept errors in the channel-riparian relationships caused by the DEM grid detail. We detail minor improvements to existing shade models and create a model (SHADE2) that calculates shading ratio (%) by riparian canopy at any time and location for given stream characteristics including stream azimuth, stream width, canopy height, canopy overhang, and height of maximum canopy overhang. Sensitivity of simulated shade to these variables is explored. We also present a new field photographic technique for quantifying shade and use this technique to provide data to test the SHADE2 algorithm. Twenty-four independent shade measurements were made in eight channels with mature hardwood riparian trees at different times of the summer and at different times of the day. Agreement between measured and modeled shade was excellent, with r2 of 0.90.

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

    PubMed Central

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

    2015-01-01

    Background Knowledge on microclimate conditions under artificial shades in a ginseng field would facilitate climate-aware management of ginseng production. Methods Weather data were measured under the shade and outside the shade at two fields located in Gochang-gun and Jeongeup-si, Korea, in 2011 and 2012 seasons to assess temperature and humidity conditions under the shade. An empirical approach was developed and validated for the estimation of leaf wetness duration (LWD) using weather measurements outside the shade as inputs to the model. Results Air temperature and relative humidity were similar between under the shade and outside the shade. For example, temperature conditions favorable for ginseng growth, e.g., between 8°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%. 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. PMID:26843827

  7. Shape Estimation from Shading, Defocus, and Correspondence Using Light-Field Angular Coherence.

    PubMed

    Tao, Michael W; Srinivasan, Pratul P; Hadap, Sunil; Rusinkiewicz, Szymon; Malik, Jitendra; Ramamoorthi, Ravi

    2017-03-01

    Light-field cameras are quickly becoming commodity items, with consumer and industrial applications. They capture many nearby views simultaneously using a single image with a micro-lens array, thereby providing a wealth of cues for depth recovery: defocus, correspondence, and shading. In particular, apart from conventional image shading, one can refocus images after acquisition, and shift one's viewpoint within the sub-apertures of the main lens, effectively obtaining multiple views. We present a principled algorithm for dense depth estimation that combines defocus and correspondence metrics. We then extend our analysis to the additional cue of shading, using it to refine fine details in the shape. By exploiting an all-in-focus image, in which pixels are expected to exhibit angular coherence, we define an optimization framework that integrates photo consistency, depth consistency, and shading consistency. We show that combining all three sources of information: defocus, correspondence, and shading, outperforms state-of-the-art light-field depth estimation algorithms in multiple scenarios.

  8. Effects of shading on early growth of Cyclobalanopsis glauca (Fagaceae) in subtropical abandoned fields: Implications for vegetation restoration

    NASA Astrophysics Data System (ADS)

    Du, Xiaojun; Liu, Canran; Yu, Xingjun; Ma, Keping

    2008-03-01

    In order to restore natural ecosystems and improve the environment, the restoration of abandoned agricultural lands to their native vegetation is urgent and challenging work. In response to a new initiative in China, the National Engineering Program on Converting Abandoned Agriculture Land to Forest Stands, this study was undertaken to seek novel approaches for accelerating forest restoration efforts. We tested the hypothesis that the late-successional tree species, Cyclobalanopsis glauca, is not able to establish and grow in full-sun environments on abandoned lands due to inhibited early growth of C. glauca seedlings. We carried out a 2-year field experiment on early growth of C. glauca in subtropical abandoned fields under three different shade treatments (no shade, fully exposed to ambient sunlight; medium shade and heavy shade, about 40% and 22% of full ambient sunlight, respectively) and compared their growth and biomass to 2-year old C. glauca seedlings growing in a natural forest environment. Our results showed that: 1) both medium shade and heavy shade treatments enhanced the establishment and early growth of C. glauca seedlings as compared to no shade, and that growth and survivorship was greatest in the heavy shade treatment; and 2) the growth and biomass of C. glauca seedlings on abandoned fields (in the cleared and prepared plots in this study) were equal to or greater than the growth and biomass of seedlings growing in nearby forests. This study supports the viewpoint that consideration of species shade tolerance is important when developing restoration management strategies.

  9. Effects of mutual shading on the regulation of photosynthesis in field-grown sorghum.

    PubMed

    Li, Tao; Liu, Li-Na; Jiang, Chuang-Dao; Liu, Yu-Jun; Shi, Lei

    2014-08-01

    In the field, close planting inevitably causes mutual shading and depression of leaf photosynthesis. To clarify the regulative mechanisms of photosynthesis under these conditions, the effects of planting density on leaf structure, gas exchange and proteomics were carefully studied in field-grown sorghum. In the absence of mineral deficiency, (1) close planting induced a significant decrease in light intensity within populations, which further resulted in much lower stomatal density and other anatomical characteristics associated with shaded leaves; (2) sorghum grown at high planting density had a lower net photosynthetic rate and stomatal conductance than those grown at low planting density; (3) approximately 62 protein spots changed their expression levels under the high planting density conditions, and 22 proteins associated with photosynthesis were identified by mass spectrometry. Further analysis revealed the depression of photosynthesis caused by mutual shading involves the regulation of leaf structure, absorption and transportation of CO2, photosynthetic electron transport, production of assimilatory power, and levels of enzymes related to the Calvin cycle. Additionally, heat shock protein and oxygen-evolving enhancer protein play important roles in photoprotection in field-grown sorghum. A model for the regulation of photosynthesis under mutual shading was suggested based on our results.

  10. Impact of shade on outdoor thermal comfort—a seasonal field study in Tempe, Arizona

    NASA Astrophysics Data System (ADS)

    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.

  11. Impact of shade on outdoor thermal comfort-a seasonal field study in Tempe, Arizona.

    PubMed

    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.

  12. Effects of shading on spike differentiation and grain yield formation of summer maize in the field.

    PubMed

    Cui, Haiyan; Camberato, James J; Jin, Libin; Zhang, Jiwang

    2015-09-01

    A field experiment was conducted to study the effects of shading on tassel and ear development and yield formation of three summer maize hybrids Zhenjie 2 (ZJ2), Denghai 605 (DH605), and Zhengdan 958 (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 stage (R1) to physiological maturity stage (R6) (treatment S1), from the sixth extended leaf stage (V6) to R1 (treatment S2) and from seeding to R6 (treatment S3). Shading had no significant effect on the time from seeding to shoot emergence (VE); however, subsequent growth and development were delayed with shading beyond this point. The differentiation time of both tassel and ear delayed, and female spike (tassel) floret differentiation, sexual organ formation time, and anthesis-silking interval (ASI) were lengthened. After shading, the total number of floret, silk, and fertilization floret reduced significantly; the number of abortive seeds increased, and the total setting percentage among different treatments showed that CK>S2>S1>S3; and the total setting percentages in S1, S2, and S3 of ZD958 were 44, 72, and 15 % respectively. The total floret number of tassel primordium differentiation, fertility rate, and seed setting rate of florets in S3 treatment was the minimum; kernels per ear decreased seriously and single ear setting percentage was only 16 %; although floret degeneration number of S2 during ear differentiation stages increased and floret fertility rate reduced than that of CK, fertilization flower seed production increased and abortive seed decreased after canceling shading. Aborted kernel of S1 increased and kernel dry weight reduced, resulting in a significant decrease of kernel number per ear and kernel weight, and the grain abortive rate of 40-62 %. In conclusion, shading changed the growth and development process and caused infertility of tassel and ear; tassel branches decreased

  13. Effects of shading on spike differentiation and grain yield formation of summer maize in the field

    NASA Astrophysics Data System (ADS)

    Cui, Haiyan; Camberato, James J.; Jin, Libin; Zhang, Jiwang

    2015-09-01

    A field experiment was conducted to study the effects of shading on tassel and ear development and yield formation of three summer maize hybrids Zhenjie 2 (ZJ2), Denghai 605 (DH605), and Zhengdan 958 (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 stage (R1) to physiological maturity stage (R6) (treatment S1), from the sixth extended leaf stage (V6) to R1 (treatment S2) and from seeding to R6 (treatment S3). Shading had no significant effect on the time from seeding to shoot emergence (VE); however, subsequent growth and development were delayed with shading beyond this point. The differentiation time of both tassel and ear delayed, and female spike (tassel) floret differentiation, sexual organ formation time, and anthesis-silking interval (ASI) were lengthened. After shading, the total number of floret, silk, and fertilization floret reduced significantly; the number of abortive seeds increased, and the total setting percentage among different treatments showed that CK>S2>S1>S3; and the total setting percentages in S1, S2, and S3 of ZD958 were 44, 72, and 15 % respectively. The total floret number of tassel primordium differentiation, fertility rate, and seed setting rate of florets in S3 treatment was the minimum; kernels per ear decreased seriously and single ear setting percentage was only 16 %; although floret degeneration number of S2 during ear differentiation stages increased and floret fertility rate reduced than that of CK, fertilization flower seed production increased and abortive seed decreased after canceling shading. Aborted kernel of S1 increased and kernel dry weight reduced, resulting in a significant decrease of kernel number per ear and kernel weight, and the grain abortive rate of 40-62 %. In conclusion, shading changed the growth and development process and caused infertility of tassel and ear; tassel branches decreased

  14. GlyphSea: Interactive Exploration of Seismic Wave Fields Using Shaded Glyphs

    NASA Astrophysics Data System (ADS)

    McQuinn, E.; Chourasia, A.; Minster, J. H.; Schulze, J.

    2010-12-01

    Earthquake simulations produce large vector fields that raise challenging visualization issues. Prior visualization strategies have typically focused on slices and volumetric rendering of scalar fields, which limits the scope of observable phenomena. We present a new interactive glyph visualization application called "GlyphSea" that allows exploration of seismic velocity fields. This work draws from a large body of glyph rendering techniques to focus on time-dependent seismic vector fields. Glyphs are capable of encoding multivariate data into a concise visual representation, which can be interpreted easily. However, that they occupy a large amount of display space, a severe drawback when dealing with dense data sets. We demonstrate how shading and texturing glyphs can alleviate this issue and provide insight into the data. We show that proper shading, positioning, scaling, and context techniques reveal features of the wave fields which are not immediately noticeable through standard vector and scalar visualization approaches. Visualization is further enhanced by using screen space ambient occlusion, jitter, halos, and displacement. These techniques are flexibly interchanged with a realtime, fully interactive, cross platform software system that runs on workstations and laptops alike. Successful design decisions stemming from collaboration between domain experts in visualization and seismology highlight the substantial benefits of interactive displays. GlyphSea used to visualize a point source simulation. This result is created interactively and shows the full time series evolution with multiple glyph types and directional cues.

  15. Influence of the Exposure Time after Removing of Covering Materials over Shading Tea Field on the Quality of Gyokuro

    NASA Astrophysics Data System (ADS)

    Sakaida, Teruki; Yoshioka, Tetsuya; Nitabaru, Juichi; Nakazono, Kentaro; Kubota, Akira; Nariyama, Hideki

    We revealed the influences of the exposure time after removing of covering materials over shading tea field for making gyokuro on the quality of made tea. As the exposure time increased, the green color of the fresh leaves faded; their total amino acid and theanine contents reduced; and the concentration of dimethyl sulfide, a representative aromatic compound in gyokuro, decreased. In contrast, the catechin content increased. The overall quality of the tea was lowered. These results indicated it was necessary to plucking of tea shoots for short time after removing of covering materials over shading tea field.

  16. Allocation strategies of savanna and forest tree seedlings in response to fire and shading: outcomes of a field experiment

    PubMed Central

    Gignoux, Jacques; Konaté, Souleymane; Lahoreau, Gaëlle; Le Roux, Xavier; Simioni, Guillaume

    2016-01-01

    The forest-savanna ecotone may be very sharp in fire-prone areas. Fire and competition for light play key roles in its maintenance, as forest and savanna tree seedlings are quickly excluded from the other ecosystem. We hypothesized a tradeoff between seedling traits linked to fire resistance and to competition for light to explain these exclusions. We compared growth- and survival-related traits of two savanna and two forest species in response to shading and fire in a field experiment. To interpret the results, we decomposed our broad hypothesis into elementary tradeoffs linked to three constraints, biomass allocation, plant architecture, and shade tolerance, that characterize both savanna and adjacent forest ecosystems. All seedlings reached similar biomasses, but forest seedlings grew taller. Savanna seedlings better survived fire after topkill and required ten times less biomass than forest seedlings to survive. Finally, only savanna seedlings responded to shading. Although results were consistent with the classification of our species as mostly adapted to shade tolerance, competition for light in the open, and fire tolerance, they raised new questions: how could savanna seedlings survive better with a 10-times lower biomass than forest seedlings? Is their shade intolerance sufficient to exclude them from forest understory? PMID:28000732

  17. Allocation strategies of savanna and forest tree seedlings in response to fire and shading: outcomes of a field experiment.

    PubMed

    Gignoux, Jacques; Konaté, Souleymane; Lahoreau, Gaëlle; Le Roux, Xavier; Simioni, Guillaume

    2016-12-21

    The forest-savanna ecotone may be very sharp in fire-prone areas. Fire and competition for light play key roles in its maintenance, as forest and savanna tree seedlings are quickly excluded from the other ecosystem. We hypothesized a tradeoff between seedling traits linked to fire resistance and to competition for light to explain these exclusions. We compared growth- and survival-related traits of two savanna and two forest species in response to shading and fire in a field experiment. To interpret the results, we decomposed our broad hypothesis into elementary tradeoffs linked to three constraints, biomass allocation, plant architecture, and shade tolerance, that characterize both savanna and adjacent forest ecosystems. All seedlings reached similar biomasses, but forest seedlings grew taller. Savanna seedlings better survived fire after topkill and required ten times less biomass than forest seedlings to survive. Finally, only savanna seedlings responded to shading. Although results were consistent with the classification of our species as mostly adapted to shade tolerance, competition for light in the open, and fire tolerance, they raised new questions: how could savanna seedlings survive better with a 10-times lower biomass than forest seedlings? Is their shade intolerance sufficient to exclude them from forest understory?

  18. Allocation strategies of savanna and forest tree seedlings in response to fire and shading: outcomes of a field experiment

    NASA Astrophysics Data System (ADS)

    Gignoux, Jacques; Konaté, Souleymane; Lahoreau, Gaëlle; Le Roux, Xavier; Simioni, Guillaume

    2016-12-01

    The forest-savanna ecotone may be very sharp in fire-prone areas. Fire and competition for light play key roles in its maintenance, as forest and savanna tree seedlings are quickly excluded from the other ecosystem. We hypothesized a tradeoff between seedling traits linked to fire resistance and to competition for light to explain these exclusions. We compared growth- and survival-related traits of two savanna and two forest species in response to shading and fire in a field experiment. To interpret the results, we decomposed our broad hypothesis into elementary tradeoffs linked to three constraints, biomass allocation, plant architecture, and shade tolerance, that characterize both savanna and adjacent forest ecosystems. All seedlings reached similar biomasses, but forest seedlings grew taller. Savanna seedlings better survived fire after topkill and required ten times less biomass than forest seedlings to survive. Finally, only savanna seedlings responded to shading. Although results were consistent with the classification of our species as mostly adapted to shade tolerance, competition for light in the open, and fire tolerance, they raised new questions: how could savanna seedlings survive better with a 10-times lower biomass than forest seedlings? Is their shade intolerance sufficient to exclude them from forest understory?

  19. Shade Avoidance

    PubMed Central

    Casal, Jorge J.

    2012-01-01

    The presence of neighboring vegetation modifies the light environment experienced by plants, generating signals that are perceived by phytochromes and cryptochromes. These signals cause large changes in plant body form and function, including enhanced growth of the hypocotyl and petioles, a more erect position of the leaves and early flowering in Arabidopsis thaliana. Collectively, these so-called shade-avoidance responses tend to reduce the degree of current or future shade by neighbors. Shade light signals increase the abundance of PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and PIF5 proteins, promote the synthesis and redirection of auxin, favor the degradation of DELLA proteins and increase the expression of auxin, gibberellins and brassinosteroid-promoted genes, among other events downstream the photoreceptors. Selectively disrupting these events by genetic or pharmacological approaches affects shade-avoidance responses with an intensity that depends on the developmental context and the environment. Shade-avoidance responses provide a model to investigate the signaling networks used by plants to take advantage of the cues provided by the environment to adjust to the challenges imposed by the environment itself. PMID:22582029

  20. Influence of sun and shade conditions on Gratiana boliviana (Coleoptera: Chrysomelidae) abundance and feeding activity on tropical soda apple (Solanaceae) under field conditions

    USDA-ARS?s Scientific Manuscript database

    Tropical soda apple (Solanum viarum Dunal) is a perennial invasive weed species which has become a serious problem in both agricultural and natural areas of the southeastern United States. A field survey was conducted at a ranch in Madison County, Florida, to assess the effect of sun and shade condi...

  1. Winter wheat and summer shade

    NASA Astrophysics Data System (ADS)

    Artru, S.; Garre, S.; Lassois, L.; Dupraz, C.

    2014-12-01

    Agroforestry research is in full expansion, but uncertainty remains on the performance of combinations of species with regard to the broad range of possible species associations. In addition, the variability of environmental conditions under which agroforestry stands can be successfully developed is unknown. Under Belgian pedoclimatic conditions, tree-crop competition for light might be the principal limiting factor in the agroforestry context. Most studies show that shade stress induces a systematic reduction of final crop yield. However, the response of a specific crop to shade is highly dependent on environmental conditions. In agroforestry systems, the tree canopy reduces the incident radiation for the crop following a dynamic spatio-temporal pattern. In this study, we will report on the efficiency of wheat under artificial dynamic shade in the experimental farm of Gembloux Agro-Bio Tech, Belgium in order to evaluate it's potential for agroforestry purposes in the same region. Wheat productivity and development under artificial shade conditions have been monitored during 1 year and the observations will be continued for 2 more years. We constructed an artificial shade structure, which mimics the light environment observed under hybrid walnut agroforestry trees: periodic fluctuation in radiation transmittance and discontinuous light quantity. We collected information on biomass development, soil state and radiation patterns in the field. Using this data, we evaluated the influence of dynamic shade, light availability and the efficiency with which energy is converted in wheat dry matter under the artificial shade treatment. This, in combination with modeling, will allow a thorough study of the potential of wheat-walnut agroforestry systems in the Hesbaye region in Belgium.

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

    Treesearch

    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...

  3. Retractable Sun Shade

    NASA Technical Reports Server (NTRS)

    Frank, A.; Derespinis, S. F.; Mockovciak, John, Jr.

    1986-01-01

    Window-shade type spring roller contains blanket, taken up by rotating cylindrical frame and held by frame over area to be shaded. Blanket made of tough, opaque polyimide material. Readily unfurled by mechanism to protect space it encloses from Sun. Blanket forms arched canopy over space and allows full access to it from below. When shading not needed, retracted mechanism stores blanket compactly. Developed for protecting sensitive Space Shuttle payloads from direct sunlight while cargo-bay doors open. Adapted to shading of greenhouses, swimming pools, and boats.

  4. Retractable Sun Shade

    NASA Technical Reports Server (NTRS)

    Frank, A.; Derespinis, S. F.; Mockovciak, John, Jr.

    1986-01-01

    Window-shade type spring roller contains blanket, taken up by rotating cylindrical frame and held by frame over area to be shaded. Blanket made of tough, opaque polyimide material. Readily unfurled by mechanism to protect space it encloses from Sun. Blanket forms arched canopy over space and allows full access to it from below. When shading not needed, retracted mechanism stores blanket compactly. Developed for protecting sensitive Space Shuttle payloads from direct sunlight while cargo-bay doors open. Adapted to shading of greenhouses, swimming pools, and boats.

  5. Surface-Shading Program

    NASA Technical Reports Server (NTRS)

    Plessel, Todd

    1992-01-01

    Surface Shading program, SURF, developed to enable interactive input of grid and solution files from PLOT3D/AMES program; to use those files in interactive creation of wire-frame, shaded, and function-mapped images of parts to view; then to put out ARCGraph standard files animated by use of GAS (COSMIC Program ARC-12379). Written in C.

  6. Disparity and shading cues cooperate for surface interpolation.

    PubMed

    Vuong, Quoc C; Domini, Fulvio; Caudek, Corrado

    2006-01-01

    In two experiments, we tested whether disparity and shading cues cooperated for surface interpolation. Observers adjusted a probe dot to/lie on a surface specified either by a sparse disparity field, a continuous stereo shading or monocular shading gradient, or both cues. Observers' adjustments were very consistent with disparity information but their adjustments were much more variable with shading information. However, observers significantly improved their precision when both cues were present, relative to when only disparity information was present. These results cannot be explained by assuming that separate modules analyze disparity and shading information, even if observers optimally combined these cues. Rather, we attribute this improvement to a process through which the shading gradient constrains the disparity field in regions where disparities cannot be directly measured. This cooperative process may be based on the natural covariation existing between these cues produced by the retinal projection of smooth surfaces.

  7. Scattered UV beneath public shade structures during winters.

    PubMed

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

    2003-08-01

    Broadband field measurements were conducted beneath three different-sized public shade structures, small, medium and large, during winter in the Southern Hemisphere. These measurements were compared with the diffuse UV to quantify the relationship of the UV under and around the shade structures to the diffuse UV. For the shade structures, a relationship between the diffuse UV and the UV in the shade has been provided for clear skies and solar zenith angles (SZA) of 49-76 degrees. This allows the prediction of the UV in the shade of these structures if the diffuse UV is known. The ultraviolet protection factors for the three shade structures ranged from 1.5 to 5.4 for decreasing SZA. For the greater SZA of 70-76 degrees, the erythemal UV in the shade was 65%, 59% and 51% of that in full sun for the small, medium and large structures, respectively. For the smaller SZA of 50-53 degrees the erythemal UV in the shade was 35%, 41% and 18% for the small, medium and large shade structures, respectively. From this research it can be concluded that the UV radiation levels in the shade in winter could cause erythema and other sun-related disorders.

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

    PubMed

    Baltzer, A; Kaufmann-Jinoian, V

    2005-04-01

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

  9. [Effects of shading on the growth, development and grain yield of summer maize].

    PubMed

    Zhang, Jiwang; Dong, Shuting; Wang, Kongjun; Hu, Changhao; Liu, Peng

    2006-04-01

    Under field condition, this paper studied the effects of shading on the growth, development, and grain yield of summer maize varieties ND108 and YD13. The results showed that shading decreased maize yield significantly, and the effect was differed with different shading period and intensity. With a shading intensity of 50% and 90%, the grain yield of ND108 and YD13 was decreased by 67.5% and 79.4%, and 82.9% and 86.7% when shading at flowering-maturing stage, and by 34.1% and 55.3%, and 47.2%, 65.7% when shading at joining-flowering stage, respectively. Shading at seedling-joining stage had a relatively smaller effect, with the grain yield decreased by 16.9% and 24.5%, and 18.9% and 24.3%, respectively. Shading had a larger effect on YD13 than on ND108, and the effect of shading period was larger than that of shading intensity. Under shading, the growth and development of maize was retarded, and the effect was increased with increasing shading intensity. Shading at joining-flowering stage affected spike differentiation significantly, reflecting in the marked decrease of the numbers of silks and tassels, and the effect was also larger on YD13 than on ND108. The leaf and plant growth was restrained significantly when shading at seedling stage and at flowering-maturing stage.

  10. Decoding figure-ground occlusions from contours and shading

    NASA Astrophysics Data System (ADS)

    Kim, Juno; Anstis, Stuart

    2016-07-01

    Visual experience of surface properties relies on accurately attributing encoded luminance variations (e.g., edges and contours) to any one of several potential environmental causes. We examined the role of differences in the local shading directions across sharp contours in (i) identifying occlusion boundaries and (ii) perceiving the depth layout of adjacent surfaces. We used graphical rendering to control the orientation of a simulated light source, and hence the shading direction between adjacent surface regions that met at a common edge. We call the difference in shading direction across the edge the delta shading angle. We found that delta-shaded edges looked like occluding boundaries. We also found that the perceived figure-ground organisation of the adjacent surface regions depended on an assumed lighting from above prior. Shaded regions experienced as convex surfaces illuminated from above were perceived as occluding surfaces in the foreground. We computed an image-based measure of delta shading using the difference in local shading direction (the orientation field) and found this model could reliably account for observer judgments of surface occlusion, better than local (in-)coherence in the orientation of isophotes across the edge alone. However, additional information from co-alignment of isophotes relative to the edge is necessary to explain figure-ground distinctions across a broad class of occlusion events. We conclude that both local and global measures of shading direction are needed to explain perceived scene organisation, and material appearance more generally.

  11. Shades of Gray.

    ERIC Educational Resources Information Center

    Nelson, John C.; Calibeo, Thomas E.

    1998-01-01

    A university's financing choices cover many shades of gray. Some off-balance-sheet financing uses no debt capacity, while others represent or imply full financial commitment. Many others fall in between. The choices made by a number of institutions in financing facility expansions or improvements are discussed, and the Moody's Investors Service…

  12. TRANSPLANTING SHADE TREES.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana. Coll. of Agriculture.

    THIS RESOURCE MATERIAL FOR USE IN HIGH SCHOOL VOCATIONAL AGRICULTURE AND ADULT FARMER CLASSES WAS DESIGNED BY SUBJECT MATTER SPECIALISTS, TEACHER EDUCATORS, SUPERVISORS, AND TEACHERS. THE OBJECTIVE IS TO HELP SOLVE PROBLEMS IN TRANSPLANTING SHADE TREES. THE MAJOR SECTION TITLES ARE STATED AS PROBLEMS -- (1) HOW SHOULD I PREPARE A TREE FOR MOVING,…

  13. Tints, Shades and Frost

    ERIC Educational Resources Information Center

    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…

  14. Shade Guide Lights: Technical Evaluation

    DTIC Science & Technology

    1988-12-01

    Vident Lumin Shade Light, ambient roomn li5ght, and the unit light. Selected shades were recorded and results were c nlzd This evaluation showed that...dentists and one dental laboratory technician on five natural teeth using the Efos Esthelite, Vident Lumin Shade Light, dental unit light (Ritter...tested: Efos Esthelite Unit Cost $300.00 Caulk/Dentsply P.O. Box 359 Milford, DE 19963 1-800-532-2S55 Vident Lumin Shade Light Unit Cost $395.00

  15. Shaded Relief, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This topographic image shows the western side of the volcanically active Kamchatka Peninsula, Russia. The data are from the first C-band mapping swath of the Shuttle Radar Topography Mission (SRTM). On the left side are four rivers, which flow northwest to the Sea of Okhotsk. These rivers are, from the south to north, Tigil, Amanina, Voyampolka, and Zhilovaya. The broad, flat floodplains of the rivers are shown in blue. These rivers are important spawning grounds for salmon. In the right side of the image is the Sredinnyy Khrebet, the volcanic mountain range that makes up the 3spine2 of the peninsula. The cluster of hills to the lower right is a field of small dormant volcanoes. High resolution SRTM topographic data will be used by geologists to study how volcanoes form and understand the hazards posed by future eruptions.

    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. 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 antenna and

  16. Lunar radiator shade

    NASA Technical Reports Server (NTRS)

    Ewert, Michael K. (Inventor)

    1992-01-01

    An apparatus for rejecting waste heat from a system located on or near the lunar equator is presented. The system utilizes a reflective catenary shaped trough deployed about a vertical radiator to shade the radiator from heat emitted by the hot lunar surface. The catenary shaped trough is constructed from a film material and is aligned relative to the sun so that incoming solar energy is focused to a line just above the vertical radiator and can thereby isolate the radiator from the effects of direct sunlight. The film is in a collapsed position between side by side support rods, all of which are in a transport case. To deploy the film and support rods, a set of parallel tracks running perpendicular to length of the support rods are extended out from the transport case. After the support tracks are deployed, the support rods are positioned equidistant from each other along the length of the support tracks so that the flexible film shade between adjacent support rods is unfolded and hangs in a catenary shaped trough. A heat radiator is supported between each pair of support rods above each hanging reflective trough.

  17. Shape from Shading in Pigeons

    ERIC Educational Resources Information Center

    Cook, Robert G.; Qadri, Muhammad A. J.; Kieres, Art; Commons-Miller, Nicholas

    2012-01-01

    Light is the origin of vision. The pattern of shading reflected from object surfaces is one of several optical features that provide fundamental information about shape and surface orientation. To understand how surface and object shading is processed by birds, six pigeons were tested with differentially illuminated convex and concave curved…

  18. Shape from Shading in Pigeons

    ERIC Educational Resources Information Center

    Cook, Robert G.; Qadri, Muhammad A. J.; Kieres, Art; Commons-Miller, Nicholas

    2012-01-01

    Light is the origin of vision. The pattern of shading reflected from object surfaces is one of several optical features that provide fundamental information about shape and surface orientation. To understand how surface and object shading is processed by birds, six pigeons were tested with differentially illuminated convex and concave curved…

  19. Perceived depth from shading boundaries.

    PubMed

    Kim, Juno; Anstis, Stuart

    2016-01-01

    Shading is well known to provide information the visual system uses to recover the three-dimensional shape of objects. We examined conditions under which patterns in shading promote the experience of a change in depth at contour boundaries, rather than a change in reflectance. In Experiment 1, we used image manipulation to illuminate different regions of a smooth surface from different directions. This manipulation imposed local differences in shading direction across edge contours (delta shading). We found that increasing the angle of delta shading, from 0° to 180°, monotonically increased perceived depth across the edge. Experiment 2 found that the perceptual splitting of shading into separate foreground and background surfaces depended on an assumed light source from above prior. Image regions perceived as foreground structures in upright images appeared farther in depth when the same images were inverted. We also found that the experienced break in surface continuity could promote the experience of amodal completion of colored contours that were ambiguous as to their depth order (Experiment 3). These findings suggest that the visual system can identify occlusion relationships based on monocular variations in local shading direction, but interprets this information according to a light source from above prior of midlevel visual processing.

  20. Genotype x shade effects for western hemlock.

    Treesearch

    G.R. Johnson; C. Cartwright

    2005-01-01

    Western hemlock (Tsuga heterophylla (Raf.) Sarg.) families were grown under different levels of shade for 2 or 3 years at two nursery sites to determine whether families performed differently relative to one another in the different shade environments. Differences were found both for levels of shade and families, but no family x shade interaction...

  1. Technology reviews: Shading systems

    SciTech Connect

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

    1992-09-01

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

  2. Hydraulic acclimation to shading in boreal conifers of varying shade tolerance.

    PubMed

    Schoonmaker, Amanda L; Hacke, Uwe G; Landhäusser, Simon M; Lieffers, Victor J; Tyree, Melvin T

    2010-03-01

    The purpose of this study was to determine how shading affects the hydraulic and wood-anatomical characteristics of four boreal conifers (Pinus banksiana, Pinus contorta, Picea glauca and Picea mariana) that differ in shade tolerance. Plants were grown in an open field and under a deciduous-dominated overstory for 6 years. Sapwood- and leaf-area specific conductivity, vulnerability curves, and anatomical measurements (light and scanning electron microscopy) were made on leading shoots from six to nine trees of each treatment combination. There was no difference in sapwood-area specific conductivity between open-grown and understory conifers, although two of four species had larger tracheid diameters in the open. Shaded conifers appeared to compensate for small diameter tracheids by changes in pit membrane structure. Scanning electron microscopy revealed that understory conifers had thinner margo strands, greater maximum pore size in the margo, and more torus extensions. All of these trends may contribute to inadequate sealing of the torus. This is supported by the fact that all species showed increased vulnerability to cavitation when grown in the understory. Although evaporative demand in an understory environment is low, a rapid change into fully exposed conditions could be detrimental for shaded conifers.

  3. Height and Gradient from Shading

    DTIC Science & Technology

    1989-05-01

    points . This report includes a review of previous work on shape from shading and pho- toclinometry. Novel features of the new scheme are introduced one at...singular points . This report includes a review of previous work on shape from shading and pho- toclinometry. Novel features of the new scheme are... optical axis (the perpendicular from the center of projection to the image plane)4 . We can align the X- and Y-axes with the image plane x- and y-axes. Let

  4. Photosynthetic responses of sun- and shade-grown barley leaves to high light: is the lower PSII connectivity in shade leaves associated with protection against excess of light?

    PubMed

    Zivcak, Marek; Brestic, Marian; Kalaji, Hazem M; Govindjee

    2014-03-01

    In this study, we have compared photosynthetic performance of barley leaves (Hordeum vulgare L.) grown under sun and shade light regimes during their entire growth period, under field conditions. Analyses were based on measurements of both slow and fast chlorophyll (Chl) a fluorescence kinetics, gas exchange, pigment composition; and of light incident on leaves during their growth. Both the shade and the sun barley leaves had similar Chl a/b and Chl/carotenoid ratios. The fluorescence induction analyses uncovered major functional differences between the sun and the shade leaves: lower connectivity among Photosystem II (PSII), decreased number of electron carriers, and limitations in electron transport between PSII and PSI in the shade leaves; but only low differences in the size of PSII antenna. We discuss the possible protective role of low connectivity between PSII units in shade leaves in keeping the excitation pressure at a lower, physiologically more acceptable level under high light conditions.

  5. Photomorphogenesis: Plants Feel Blue in the Shade.

    PubMed

    Franklin, Keara A

    2016-12-19

    Plants integrate multiple environmental signals to detect and avoid shading from neighbouring vegetation. Two new studies highlight the importance of blue light in the regulation of stem elongation and bending during shade escape.

  6. Cotyledon-Generated Auxin Is Required for Shade-Induced Hypocotyl Growth in Brassica rapa.

    PubMed

    Procko, Carl; Crenshaw, Charisse Michelle; Ljung, Karin; Noel, Joseph Patrick; Chory, Joanne

    2014-07-01

    Plant architecture is optimized for the local light environment. In response to foliar shade or neighbor proximity (low red to far-red light), some plant species exhibit shade-avoiding phenotypes, including increased stem and hypocotyl growth, which increases the likelihood of outgrowing competitor plants. If shade persists, early flowering and the reallocation of growth resources to stem elongation ultimately affect the yield of harvestable tissues in crop species. Previous studies have shown that hypocotyl growth in low red to far-red shade is largely dependent on the photoreceptor phytochrome B and the phytohormone auxin. However, where shade is perceived in the plant and how auxin regulates growth spatially are less well understood. Using the oilseed and vegetable crop species Brassica rapa, we show that the perception of low red to far-red shade by the cotyledons triggers hypocotyl cell elongation and auxin target gene expression. Furthermore, we find that following shade perception, elevated auxin levels occur in a basipetal gradient away from the cotyledons and that this is coincident with a gradient of auxin target gene induction. These results show that cotyledon-generated auxin regulates hypocotyl elongation. In addition, we find in mature B. rapa plants that simulated shade does not affect seed oil composition but may affect seed yield. This suggests that in field settings where mutual shading between plants may occur, a balance between plant density and seed yield per plant needs to be achieved for maximum oil yield, while oil composition might remain constant.

  7. Coastal Chile Shaded Relief View

    NASA Image and Video Library

    2010-03-04

    This color-coded shaded relief view from NASA Shuttle Radar Topography Mission of coastal Chile indicates the epicenter red marker of the 8.8 earthquake on Feb. 27, 2010, just offshore of the Maule region in the Bahia de Chanco.

  8. Shade structure design and evaluation

    USDA-ARS?s Scientific Manuscript database

    Shade structures are often considered as a method of reducing heat stress in feedlot cattle during extreme summer conditions. Design and material selection present challenges to meet a range of criteria that include: cost, effectiveness, durability, low maintenance, and minimal interference with no...

  9. Shaded Relief Color Wrapped, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This shaded relief topographic image shows the western side of the volcanically active Kamchatka Peninsula, Russia. The data are from the first C-band mapping swath of the Shuttle Radar Topography Mission (SRTM). On the left side are five rivers, which flow northwest to the Sea of Okhotsk. These rivers are, from the south to north, Tigil, Amanina, Voyampolka, Zhilovaya, and Kakhtana. The broad, flat floodplains of the rivers are shown in yellow. These rivers are important spawning grounds for salmon. In the right side of the image is the Sredinnyy Khrebet, the volcanic mountain range that makes up the 3spine2 of the peninsula. The cluster of hills to the lower right is a field of small dormant volcanoes. High resolution SRTM topographic data will be used by geologists to study how volcanoes form and understand the hazards posed by future eruptions.

    This image was generated using topographic data from the Shuttle Radar Topography Mission. Colors show the elevation as measured by SRTM. Each cycle of colors (from red through green back to red) represents an equal amount of elevation difference (400 meters, or 1300 feet)similar to contour lines on a standard topographic map. This image contains about 2300 meters (7500 feet) of total relief. For the shading, 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. 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

  10. Topography from shading and stereo

    NASA Technical Reports Server (NTRS)

    Horn, Berthold P.; Caplinger, Michael

    1993-01-01

    Methods exploiting photometric information in images that have been developed in machine vision can be applied to planetary imagery. Present techniques, however, focus on one visual cue, such as shading or binocular stereo, and produce results that are either not very accurate in an absolute sense or provide information only at few points on the surface. We plan to integrate shape from shading, binocular stereo and photometric stereo to yield a robust system for recovering detailed surface shape and surface reflectance information. Such a system will be useful in producing quantitative information from the vast volume of imagery being received, as well as in helping visualize the underlying surface. The work will be carried out on a popular computing platform so that it will be easily accessible to other workers.

  11. Topography from shading and stereo

    NASA Technical Reports Server (NTRS)

    Horn, Berthold P.; Caplinger, Michael

    1992-01-01

    Methods exploiting photometric information in images that have been developed in machine vision can be applied to planetary imagery. Present techniques, however, focus on one visual cue, such as shading or binocular stereo, and produce results that are either not very accurate in an absolute sense or provide information only at few points on the surface. We plan to integrate shape from shading, binocular stereo and photometric stereo to yield a robust system for recovering detailed surface shape and surface reflectance information. Such a system will be useful in producing quantitative information from the vast volume of imagery being received, as well as in helping visualize the underlying surface. The work will be carried out on a popular computing platform so that it will be easily accessible to other workers.

  12. Shade distribution of commercial resin composites and color difference with shade guide tabs.

    PubMed

    Park, Seung-Kook; Lee, Yong-Keun

    2007-10-01

    To determine the shade distribution of varied shades of contemporary resin composites, and to measure the color difference (deltaE*ab) between individual shades of resin composites and the nearest shade tabs, which showed the smallest color difference with each shade of resin composite, in the VITA shade guide. Eight light-curing resin composites, with a total of 41 shades, were studied. Color of specimens was measured on a reflection spectrophotometer over a white background. Ranges and distributions of CIE L*, C*ab, a* and b* values of each brand of resin composites were determined. Color difference between each shade of resin composites and each shade of the shade guide tabs were calculated, and the nearest shade guide tab was selected. The range of CIE L* value for eight brands of resin composites was 3.2-9.0, that of C*ab was 2.5-11.6, that of CIE a* value was 1.1-5.8, and that of CIE b* value was 5.9-11.5. Color differences (deltaE*ab) between each shade of resin composites and the nearest shade tab of the shade guide was 0.9-12.8.

  13. Topography from shading and stereo

    NASA Technical Reports Server (NTRS)

    Horn, Berthold K. P.

    1994-01-01

    Methods exploiting photometric information in images that have been developed in machine vision can be applied to planetary imagery. Integrating shape from shading, binocular stereo, and photometric stereo yields a robust system for recovering detailed surface shape and surface reflectance information. Such a system is useful in producing quantitative information from the vast volume of imagery being received, as well as in helping visualize the underlying surface.

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

    PubMed

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

    PubMed

    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.

  16. Field-Grown Grapevine Berries Use Carotenoids and the Associated Xanthophyll Cycles to Acclimate to UV Exposure Differentially in High and Low Light (Shade) Conditions

    PubMed Central

    Joubert, Chandré; Young, Philip R.; Eyéghé-Bickong, Hans A.; Vivier, Melané A.

    2016-01-01

    Light quantity and quality modulate grapevine development and influence berry metabolic processes. Here we studied light as an information signal for developing and ripening grape berries. A Vitis vinifera Sauvignon Blanc field experiment was used to identify the impacts of UVB on core metabolic processes in the berries under both high light (HL) and low light (LL) microclimates. The primary objective was therefore to identify UVB-specific responses on berry processes and metabolites and distinguish them from those responses elicited by variations in light incidence. Canopy manipulation at the bunch zone via early leaf removal, combined with UVB-excluding acrylic sheets installed over the bunch zones resulted in four bunch microclimates: (1) HL (control); (2) LL (control); (3) HL with UVB attenuation and (4) LL with UVB attenuation. Metabolite profiles of three berry developmental stages showed predictable changes to known UV-responsive compound classes in a typical UV acclimation (versus UV damage) response. Interestingly, the berries employed carotenoids and the associated xanthophyll cycles to acclimate to UV exposure and the berry responses differed between HL and LL conditions, particularly in the developmental stages where berries are still photosynthetically active. The developmental stage of the berries was an important factor to consider in interpreting the data. The green berries responded to the different exposure and/or UVB attenuation signals with metabolites that indicate that the berries actively managed its metabolism in relation to the exposure levels, displaying metabolic plasticity in the photosynthesis-related metabolites. Core processes such as photosynthesis, photo-inhibition and acclimation were maintained by differentially modulating metabolites under the four treatments. Ripe berries also responded metabolically to the light quality and quantity, but mostly formed compounds (volatiles and polyphenols) that have direct antioxidant and/or

  17. Field-Grown Grapevine Berries Use Carotenoids and the Associated Xanthophyll Cycles to Acclimate to UV Exposure Differentially in High and Low Light (Shade) Conditions.

    PubMed

    Joubert, Chandré; Young, Philip R; Eyéghé-Bickong, Hans A; Vivier, Melané A

    2016-01-01

    Light quantity and quality modulate grapevine development and influence berry metabolic processes. Here we studied light as an information signal for developing and ripening grape berries. A Vitis vinifera Sauvignon Blanc field experiment was used to identify the impacts of UVB on core metabolic processes in the berries under both high light (HL) and low light (LL) microclimates. The primary objective was therefore to identify UVB-specific responses on berry processes and metabolites and distinguish them from those responses elicited by variations in light incidence. Canopy manipulation at the bunch zone via early leaf removal, combined with UVB-excluding acrylic sheets installed over the bunch zones resulted in four bunch microclimates: (1) HL (control); (2) LL (control); (3) HL with UVB attenuation and (4) LL with UVB attenuation. Metabolite profiles of three berry developmental stages showed predictable changes to known UV-responsive compound classes in a typical UV acclimation (versus UV damage) response. Interestingly, the berries employed carotenoids and the associated xanthophyll cycles to acclimate to UV exposure and the berry responses differed between HL and LL conditions, particularly in the developmental stages where berries are still photosynthetically active. The developmental stage of the berries was an important factor to consider in interpreting the data. The green berries responded to the different exposure and/or UVB attenuation signals with metabolites that indicate that the berries actively managed its metabolism in relation to the exposure levels, displaying metabolic plasticity in the photosynthesis-related metabolites. Core processes such as photosynthesis, photo-inhibition and acclimation were maintained by differentially modulating metabolites under the four treatments. Ripe berries also responded metabolically to the light quality and quantity, but mostly formed compounds (volatiles and polyphenols) that have direct antioxidant and

  18. Shade tolerance: when growing tall is not an option.

    PubMed

    Gommers, Charlotte M M; Visser, Eric J W; St Onge, Kate R; Voesenek, Laurentius A C J; Pierik, Ronald

    2013-02-01

    Two different plant strategies exist to deal with shade: shade avoidance and shade tolerance. All shade-exposed plants optimize photosynthesis to adapt to the decrease in light quality and quantity. When shaded, most species in open habitats express the shade-avoidance syndrome, a growth response to escape shade. Shade-tolerant species from forest understories cannot outgrow surrounding trees and adopt a tolerance response. Unlike shade avoidance, virtually nothing is known about regulation of shade tolerance. In this opinion article, we discuss potential modes of molecular regulation to adopt a shade-tolerance rather than a shade-avoidance strategy. We argue that molecular approaches using model and non-model species should help identify the molecular pathways that underpin shade tolerance, thus providing knowledge for further crop improvement.

  19. Description of an exact, recursive method to simplify shading calculations

    NASA Astrophysics Data System (ADS)

    Nawrocki, A. D.; Kammerud, R.

    An exact, recursive method called SHADE is described which attempts to simplify shading calculations as performed by a programmable calculator or microcomputer. Preliminary applications of SHADE using a Hewlett Packard HP-41C programmable calculator are outlined. For a given solar hour, SHADE is used to compute the following quantities for overhang and side fin combinations which shade various openings: the percentage of the total area of the opening which is shaded; the shaded area itself; the cosine of the angle of incidence between the Sun and glazing surface; the direct insolation at this surface, with and without shading; and the direct solar power at this surface, with and without shading.

  20. Overexpression of phytochrome A and its hyperactive mutant improves shade tolerance and turf quality in creeping bentgrass and zoysiagrass.

    PubMed

    Ganesan, Markkandan; Han, Yun-Jeong; Bae, Tae-Woong; Hwang, Ok-Jin; Chandrasekhar, Thummala; Chandrasekkhar, Thummala; Shin, Ah-Young; Goh, Chang-Hyo; Nishiguchi, Satoshi; Song, In-Ja; Lee, Hyo-Yeon; Kim, Jeong-Il; Song, Pill-Soon

    2012-10-01

    Phytochrome A (phyA) in higher plants is known to function as a far-red/shade light-sensing photoreceptor in suppressing shade avoidance responses (SARs) to shade stress. In this paper, the Avena PHYA gene was introduced into creeping bentgrass (Agrostis stolonifera L.) and zoysiagrass (Zoysia japonica Steud.) to improve turf quality by suppressing the SARs. In addition to wild-type PHYA, a hyperactive mutant gene (S599A-PHYA), in which a phosphorylation site involved in light-signal attenuation was removed, was also transformed into the turfgrasses. Phenotypic traits of the transgenic plants were compared to assess the suppression of SARs under a simulated shade condition and outdoor field conditions after three growth seasons. Under the shade condition, the S599A-PhyA transgenic creeping bentgrass plants showed shade avoidance-suppressing phenotypes with a 45 % shorter leaf lengths, 24 % shorter internode lengths, and twofold increases in chlorophyll concentrations when compared with control plants. Transgenic zoysiagrass plants overexpressing S599A-PHYA also showed shade-tolerant phenotypes under the shade condition with reductions in leaf length (15 %), internode length (30 %), leaf length/width ratio (19 %) and leaf area (22 %), as well as increases in chlorophyll contents (19 %) and runner lengths (30 %) compared to control plants. The phenotypes of transgenic zoysiagrass were also investigated in dense field habitats, and the transgenic turfgrass exhibited shade-tolerant phenotypes similar to those observed under laboratory shade conditions. Therefore, the present study suggests that the hyperactive phyA is effective for the development of shade-tolerant plants, and that the shade tolerance nature is sustained under field conditions.

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

    PubMed

    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

  2. Partial shade stress test for thin-film photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Silverman, Timothy J.; Deceglie, Michael G.; Deline, Chris; Kurtz, Sarah

    2015-09-01

    Partial shade of monolithic thin-film PV modules can cause reverse-bias conditions leading to permanent damage. In this work, we introduce a partial shade stress test for thin-film PV modules that quantifies permanent performance loss. The test reproduces shading and loading conditions that may occur in the field. It accounts for reversible light-induced performance changes and for the effects of light-enhanced reverse breakdown. We simulated the test procedure using a computer model that predicts the local voltage, current and temperature stress resulting from partial shade. We also performed the test on three commercial module types. Each module type we tested suffered permanent damage during masked ash testing totaling < 2 s of light exposure. During the subsequent stress test these module types lost 4%{11% in Pmp due to widespread formation of new shunts. One module type showed a substantial worsening of the Pmp loss upon light stabilization, underscoring the importance of this practice for proper quantification of damage.

  3. Dental shade matching using a digital camera.

    PubMed

    Tam, W K; Lee, H J

    2012-12-01

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

  4. The shading cue in context

    PubMed Central

    Wagemans, Johan; van Doorn, Andrea J; Koenderink, Jan J

    2010-01-01

    The shading cue is supposed to be a major factor in monocular stereopsis. However, the hypothesis is hardly corroborated by available data. For instance, the conventional stimulus used in perception research, which involves a circular disk with monotonic luminance gradient on a uniform surround, is theoretically ‘explained’ by any quadric surface, including spherical caps or cups (the conventional response categories), cylindrical ruts or ridges, and saddle surfaces. Whereas cylindrical ruts or ridges are reported when the outline is changed from circular to square, saddle surfaces are never reported. We introduce a method that allows us to differentiate between such possible responses. We report observations on a number of variations of the conventional stimulus, including variations of shape and quality of the boundary, and contexts that allow the observer to infer illumination direction. We find strong and expected influences of outline shape, but, perhaps surprisingly, we fail to find any influence of context, and only partial influence of outline quality. Moreover, we report appreciable differences within the generic population. We trace some of the idiosyncrasies (as compared to shape from shading algorithms) of the human observer to generic properties of the environment, in particular the fact that many objects are limited in size and elliptically convex over most of their boundaries. PMID:23145221

  5. Effects of Shading on Cercospora Leaf Spot in Bigleaf Hydrangea

    USDA-ARS?s Scientific Manuscript database

    Shading densities significantly affected severity of Cercospora leaf spot on bigleaf hydrangeas. In general, lower disease severities were associated with higher shading densities. However, significantly differences in disease severities among cultivars could not be detected in higher shading densi...

  6. New entrance shade design for SIRTF

    NASA Technical Reports Server (NTRS)

    Davis, Paul K.

    1989-01-01

    A new design for the entrance shade for the Space Infrared Telescope Facility (SIRTF) is presented. The evolution of the entrance shade began with a simple frustum, symmetrical about the telescope axis, when SIRTF was expected to be Shuttle-attached. With the change to a free-flying SIRTF this frustum was cut off at an angle. The telescope will be operated so that whenever not in the earth's shadow the high side is kept toward the sun. However, the entrance shade interior itself will be so warm that the optics, including the secondary mirror and its mechanisms and support structure, will be restricted to the rear part of the barrel, termed the aftbaffle, which is shaded from the interior of the entrance shade by the forebaffle. This is best accomplished by the most recent design in which the axis of the entrance shade is offset from the telescope axis. This results in a shorter entrance shade, shorter forebaffle, and a shaded region within the barrel which is symmetrical about the telescope axis. All of these are advantageous.

  7. Effect of shade on atmospheric oxidants (smog)

    SciTech Connect

    Stewart, W.S.; Wilken, D.H.

    1985-01-01

    A series of experiments utilizing atmospheric smog were conducted comparing simultaneously the oxidant level in sunlight and under shade. From the results of the experiments, it is suggested that the undesirable effects of smog in a localized area may be reduced by the planting of shade trees, vines, shrubs and encouraging a denser growth of vegetation.

  8. Selection of Shade Tolerant Tall Fescue Genotypes

    USDA-ARS?s Scientific Manuscript database

    Tall fescue (Schedonorus arundinaceus) is genetically variable for many agronomic traits, so it might be possible to increase its persistence and productivity in shaded agroforestry applications. The objective of this research was to identify high yielding, shade-tolerant genotypes. Seed was obtai...

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

    PubMed

    Salgado-Luarte, Cristian; Gianoli, Ernesto

    2010-07-07

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

  10. Herbivory on Temperate Rainforest Seedlings in Sun and Shade: Resistance, Tolerance and Habitat Distribution

    PubMed Central

    Salgado-Luarte, Cristian; Gianoli, Ernesto

    2010-01-01

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

  11. Cotyledon-Generated Auxin Is Required for Shade-Induced Hypocotyl Growth in Brassica rapa1[C][W][OPEN

    PubMed Central

    Procko, Carl; Crenshaw, Charisse Michelle; Ljung, Karin; Noel, Joseph Patrick; Chory, Joanne

    2014-01-01

    Plant architecture is optimized for the local light environment. In response to foliar shade or neighbor proximity (low red to far-red light), some plant species exhibit shade-avoiding phenotypes, including increased stem and hypocotyl growth, which increases the likelihood of outgrowing competitor plants. If shade persists, early flowering and the reallocation of growth resources to stem elongation ultimately affect the yield of harvestable tissues in crop species. Previous studies have shown that hypocotyl growth in low red to far-red shade is largely dependent on the photoreceptor phytochrome B and the phytohormone auxin. However, where shade is perceived in the plant and how auxin regulates growth spatially are less well understood. Using the oilseed and vegetable crop species Brassica rapa, we show that the perception of low red to far-red shade by the cotyledons triggers hypocotyl cell elongation and auxin target gene expression. Furthermore, we find that following shade perception, elevated auxin levels occur in a basipetal gradient away from the cotyledons and that this is coincident with a gradient of auxin target gene induction. These results show that cotyledon-generated auxin regulates hypocotyl elongation. In addition, we find in mature B. rapa plants that simulated shade does not affect seed oil composition but may affect seed yield. This suggests that in field settings where mutual shading between plants may occur, a balance between plant density and seed yield per plant needs to be achieved for maximum oil yield, while oil composition might remain constant. PMID:24891610

  12. The development of a novel shade selection program for fixed shade translucent dental materials.

    PubMed

    Carney, Melody N; Johnston, William M

    2017-07-01

    The objective of this study was to develop a shade selection program that predicts the shade choice with the smallest CIEDE2000 color difference for dental composite resin restorations when given a backing and target shade. By utilizing previously generated regression models, a database of spectral reflectance information, and principles of Kubelka-Munk layering, a highly accurate shade selection program was designed. Using SAS 9.3 Statistical Analysis Software, a shade selection program was developed that incorporated Kubelka-Munk layering data of Herculite Ultra and Estelite Omega composite resins from a characterized database of absorption and scattering information. Test scenarios represented an inquiry based off of a backing selection shade (Shade B) and a target selection shade (ShadeT). For the simulation, the thickness of the layer on the backing was 1.9mm and the CIE illuminant was D65. The selection program was designed to select the shade that would give the lowest CIEDE2000 color difference when selected for the specific target and backing. When using the 3-D Vita shade guide, analysis between direct reflectance data and RGB data regressed to reflectance data was included in order to verify accuracy of the regression. Test scenarios indicated a systematic and accurate shade selection system by suggesting a shade that resulted in a CIEDE2000 color difference of zero when using the same target and backing shades. Most scenarios of backing and target combinations gave at least one option that was beneath the acceptability threshold indicating a clinically acceptable shade match. Many test scenarios indicated options that were beneath the perceptibility threshold indicating a highly accurate process of shade selection. There was generally little variability in the CIEDE2000 color differences when using the reflectance data versus the RGB regression data as input into the shade selection program further verifying the accuracy of a previously generated

  13. Shade estimation over streams using distributed temperature sensing

    NASA Astrophysics Data System (ADS)

    Petrides, A. C.; Huff, J.; Arik, A.; van de Giesen, N.; Kennedy, A. M.; Thomas, C. K.; Selker, J. S.

    2011-07-01

    The characterization of temporal and spatial distribution of sunlight is essential for understanding energy transport in natural ecosystems. Fiber-optic distributed temperature sensing (DTS) allows meter resolution measurements of temperature at subminute resolution. The difference in temperature due to absorption and reflection of a pair of helically twisted black and white fiber-optic cables was measured with a DTS to document areas exposed to sunlight over the Walla Walla River. A high correlation (R2 = 0.99) was found between DTS-based results and manual field observations of effective shade. These preliminary results provide proof of the concept that this method can be used for estimating the effective shade at fine spatial resolutions. Potential shortcomings and the need for a more quantitative physical model are suggested for further research.

  14. Partial Shade Stress Test for Thin-Film Photovoltaic Modules: Preprint

    SciTech Connect

    Silverman, Timothy J.; Deceglie, Michael G.; Deline, Chris; Kurtz, Sarah

    2015-09-02

    Partial shade of monolithic thin-film PV modules can cause reverse-bias conditions leading to permanent damage. In this work, we propose a partial shade stress test for thin-film PV modules that quantifies permanent performance loss. We designed the test with the aid of a computer model that predicts the local voltage, current and temperature stress that result from partial shade. The model predicts the module-scale interactions among the illumination pattern, the electrical properties of the photovoltaic material and the thermal properties of the module package. The test reproduces shading and loading conditions that may occur in the field. It accounts for reversible light-induced performance changes and for additional stress that may be introduced by light-enhanced reverse breakdown. We present simulated and experimental results from the application of the proposed test.

  15. Series-connected shaded modules to address partial shading conditions in SPV systems

    NASA Astrophysics Data System (ADS)

    Pareek, Smita; Dahiya, Ratna

    2016-03-01

    With the progress of technology and reduced cost of PV cells, the PV systems are being installed in many countries, including India. Even though this method of power generation has sufficient potential but its effective utilization is still lacking. This is because the output power of PV cells depends on many factors like insolation, temperature, climate conditions prevailing nearby, aging, using modules from different technologies/manufacturers or partial shading conditions. Among these factors, partial shading causes major reduction in output power despite the size of PV systems. As a result, the produced power is lower than the expected value. The connection of modules to each other has great impact on output power if they are prone to partial shading conditions. In this paper, PV arrays are investigated under partial shading conditions. The results show that partial shading losses can be minimized by connecting shaded modules in series rather than in parallel.

  16. Shaded Relief Color Wrapped, Kamchatka Peninsula, Russia

    NASA Image and Video Library

    2000-02-16

    This shaded relief topographic acquired by NASA Shuttle Radar Topography Mission SRTM image from data collected on February 12, 2000 shows the western side of the volcanically active Kamchatka Peninsula, Russia.

  17. Ethnicity and perception of dental shade esthetics.

    PubMed

    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 ρ<0.4). Although no significant association was found in this sample between ethnicity and attitude towards dental esthetics with regard to tooth shade, both ethnicity and dental esthetics are very diverse terms with multiple

  18. Dynamic Shade and Irradiance Simulation of Aquatic ...

    EPA Pesticide Factsheets

    Penumbra is a landscape shade and irradiance simulation model that simulates how solar energy spatially and temporally interacts within dynamic ecosystems such as riparian zones, forests, and other terrain that cast topological shadows. Direct and indirect solar energy accumulates across landscapes and is the main energy driver for increasing aquatic and landscape temperatures at both local and holistic scales. Landscape disturbances such as landuse change, clear cutting, and fire can cause significant variations in the resulting irradiance reaching particular locations. Penumbra can simulate solar angles and irradiance at definable temporal grains as low as one minute while simulating landscape shadowing up to an entire year. Landscapes can be represented at sub-meter resolutions with appropriate spatial data inputs, such as field data or elevation and surface object heights derived from light detection and ranging (LiDAR) data. This work describes Penumbra’s framework and methodology, external model integration capability, and appropriate model application for a variety of watershed restoration project types. First, an overview of Penumbra’s framework reveals what this model adds to the existing ecological modeling domain. Second, Penumbra’s stand-alone and integration modes are explained and demonstrated. Stand-alone modeling results are showcased within the 3-D visualization tool VISTAS (VISualizing Terrestrial-Aquatic Systems), which fluently summariz

  19. Effect of shading on the switching of bypass diodes in PV modules

    NASA Astrophysics Data System (ADS)

    Shiradkar, Narendra; Schneller, Eric; Dhere, Neelkanth; Gade, Vivek

    2014-10-01

    Bypass diodes are installed in Photovoltaic (PV) modules in order to prevent the application of high reverse voltage across the shaded cells in the event of partial shading of the module. Crystalline silicon (c-Si) modules have one bypass diode per 18-20 cells while thin film modules have at most one bypass diode per module. Ideally, bypass diodes are expected to turn on as soon as a current mismatch is detected between various strings of cells inside the module, which typically occurs in the event of partial shading. However, limited information is available on the actual switching characteristics of bypass diodes in field. In this paper, effect of incremental shading of various cells on the flasher I-V curve of a commercial 60-cell c-Si module was studied. Cell combinations in various strings were shaded with operational bypass diodes in the module and effect on module performance parameters such as Voc, Isc, Pmax and Fill Factor was discussed. Consequently one bypass diode in the module was short circuited and open circuited respectively and again the effect of shading on the I-V curve was investigated. Techniques for identifying short circuited and open circuited bypass diodes from I-V curve are presented.

  20. Effect of Late Planting and Shading on Cellulose Synthesis during Cotton Fiber Secondary Wall Development

    PubMed Central

    Chen, Ji; Lv, Fengjuan; Liu, Jingran; Ma, Yina; Wang, Youhua; Chen, Binglin; Meng, Yali; Zhou, Zhiguo; Oosterhuis, Derrick M.

    2014-01-01

    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. PMID:25133819

  1. Seeds Use Temperature Cues to Ensure Germination under Nurse-plant Shade in Xeric Kalahari Savannah

    PubMed Central

    Kos, Martijn; Poschlod, Peter

    2007-01-01

    Background and Aims In arid environments many plant species are found associated with the canopies of woody perennials. Favourable conditions for establishment under canopies are likely to be associated with shade, but under canopies shade is distributed patchily and differs in quality. Diurnal temperature fluctuations and maximum temperatures could be reliable indicators of safe sites. Here, an examination is made as to whether canopy-associated species use temperature cues to germinate in shade patches, rather than matrix areas between trees. Methods The study was carried out in arid southern Kalahari savannah (Republic of South Africa). Perennial and annual species associated with Acacia erioloba trees and matrix species were germinated at temperature regimes resembling shaded and unshaded conditions. Soil temperature was measured in the field. Key Results Germination of all fleshy-fruited perennial acacia-associated species and two annual acacia-associated species was inhibited by the temperature regime resembling unshaded conditions compared with at least one of the regimes resembling shaded conditions. Inhibition in perennials decreased with seed mass, probably reflecting that smaller seedlings are more vulnerable to drought. Germination of matrix species was not inhibited by the unshaded temperature regime and in several cases it increased germination compared with shaded temperature regimes or constant temperature. Using phylogenetically independent contrasts a significant positive relationship was found between canopy association and the germination at shade temperatures relative to unshaded temperatures. Conclusions The data support the hypothesis that canopy species have developed mechanisms to prevent germination in open sun conditions. The results and data from the literature show that inhibition of germination at temperature regimes characteristic of open sun conditions can be found in fleshy-fruited species of widely divergent taxonomic groups. It is

  2. Effect of late planting and shading on cellulose synthesis during cotton fiber secondary wall development.

    PubMed

    Chen, Ji; Lv, Fengjuan; Liu, Jingran; Ma, Yina; Wang, Youhua; Chen, Binglin; Meng, Yali; Zhou, Zhiguo; Oosterhuis, Derrick M

    2014-01-01

    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.

  3. Seeds use temperature cues to ensure germination under nurse-plant shade in xeric Kalahari savannah.

    PubMed

    Kos, Martijn; Poschlod, Peter

    2007-04-01

    In arid environments many plant species are found associated with the canopies of woody perennials. Favourable conditions for establishment under canopies are likely to be associated with shade, but under canopies shade is distributed patchily and differs in quality. Diurnal temperature fluctuations and maximum temperatures could be reliable indicators of safe sites. Here, an examination is made as to whether canopy-associated species use temperature cues to germinate in shade patches, rather than matrix areas between trees. The study was carried out in arid southern Kalahari savannah (Republic of South Africa). Perennial and annual species associated with Acacia erioloba trees and matrix species were germinated at temperature regimes resembling shaded and unshaded conditions. Soil temperature was measured in the field. Germination of all fleshy-fruited perennial acacia-associated species and two annual acacia-associated species was inhibited by the temperature regime resembling unshaded conditions compared with at least one of the regimes resembling shaded conditions. Inhibition in perennials decreased with seed mass, probably reflecting that smaller seedlings are more vulnerable to drought. Germination of matrix species was not inhibited by the unshaded temperature regime and in several cases it increased germination compared with shaded temperature regimes or constant temperature. Using phylogenetically independent contrasts a significant positive relationship was found between canopy association and the germination at shade temperatures relative to unshaded temperatures. The data support the hypothesis that canopy species have developed mechanisms to prevent germination in open sun conditions. The results and data from the literature show that inhibition of germination at temperature regimes characteristic of open sun conditions can be found in fleshy-fruited species of widely divergent taxonomic groups. It is predicted that germination mechanisms to detect

  4. SHADING MASK: A computer-based teaching tool for sun shading devices

    SciTech Connect

    Setiadarma, E.; Schiler, M.

    1996-10-01

    Sun shading devices affect natural lighting, ventilation, solar gain, and overall building performance. Few architecture students, architects, and designers have applied solar shading as a useful tool to reduce glare, control light intensity and radiation, and minimize the cooling load on their project. SHADING MASK is a computer-based teaching tool that uses Edward Mazria`s rectangular sun path diagram as a basis. The tool explains the basic theory of solar control, generates sun path diagrams; allows the design of overhangs, fins, and eggcrates types of shading devices; calculate solar angles and shading masks; and provides case study examples of actual buildings. It is a demonstration of how to integrate theory into a teaching/simulation tool to make important solar control information easily accessible to students, architects, and designers.

  5. Measured and estimated performance of a fleet of shaded photovoltaic systems with string and module-level inverters

    DOE PAGES

    MacAlpine, Sara; Deline, Chris; Dobos, Aron

    2017-03-16

    Shade obstructions can significantly impact the performance of photovoltaic (PV) systems. Although there are many models for partially shaded PV arrays, there is a lack of information available regarding their accuracy and uncertainty when compared with actual field performance. This work assesses the recorded performance of 46 residential PV systems, equipped with either string-level or module-level inverters, under a variety of shading conditions. We compare their energy production data to annual PV performance predictions, with a focus on the practical models developed here for National Renewable Energy Laboratory's system advisor model software. This includes assessment of shade extent on eachmore » PV system by using traditional onsite surveys and newer 3D obstruction modelling. The electrical impact of shade is modelled by either a nonlinear performance model or assumption of linear impact with shade extent, depending on the inverter type. When applied to the fleet of residential PV systems, performance is predicted with median annual bias errors of 2.5% or less, for systems with up to 20% estimated shading loss. The partial shade models are not found to add appreciable uncertainty to annual predictions of energy production for this fleet of systems but do introduce a monthly root-mean-square error of approximately 4%-9% due to seasonal effects. Here the use of a detailed 3D model results in similar or improved accuracy over site survey methods, indicating that, with proper description of shade obstructions, modelling of partially shaded PV arrays can be done completely remotely, potentially saving time and cost.« less

  6. Effects of Nitrogen and Shading on Root Morphologies, Nutrient Accumulation, and Photosynthetic Parameters in Different Rice Genotypes

    PubMed Central

    Pan, Shenggang; Liu, Haidong; Mo, Zhaowen; Patterson, Bob; Duan, Meiyang; Tian, Hua; Hu, Shuijing; Tang, Xiangru

    2016-01-01

    Nitrogen availability and illumination intensity are two key factors which affect rice growth. However, their influences on total nitrogen accumulation, photosynthetic rate, root morphologies, and yields are not fully understood. We conducted two field experiments to (1) evaluate the effects of shading under different N treatments on photosynthetic parameters, root morphologies, total nutrient accumulation, and grain yields of rice; and (2) elucidate the relationship between total nutrient accumulation and root morphologies under different shading conditions and nitrogen treatments. Three nitrogen rates, three shading treatments, and three different rice cultivars were used in two field experiments. Double shading during the grain-filling stage decreased total nutrient accumulation, altered root morphological characteristics, and decreased yields in rice. There were also significant interaction effects between nitrogen and shading on photosynthetic rate, transpiration rate, and total root length, root superficial area, and root volume. Significant interactions were found among cultivars and shading for photosynthetic rate and transpiration rate. Correlation analysis revealed that total nitrogen accumulation (TNA) and potassium accumulation (TKA) were significantly positively correlated with total root length, root superficial area, and root volume. N application could alleviate the detrimental effects of shading on total nutrient accumulation and grain yield in rice. PMID:27557779

  7. Effects of Nitrogen and Shading on Root Morphologies, Nutrient Accumulation, and Photosynthetic Parameters in Different Rice Genotypes.

    PubMed

    Pan, Shenggang; Liu, Haidong; Mo, Zhaowen; Patterson, Bob; Duan, Meiyang; Tian, Hua; Hu, Shuijing; Tang, Xiangru

    2016-08-25

    Nitrogen availability and illumination intensity are two key factors which affect rice growth. However, their influences on total nitrogen accumulation, photosynthetic rate, root morphologies, and yields are not fully understood. We conducted two field experiments to (1) evaluate the effects of shading under different N treatments on photosynthetic parameters, root morphologies, total nutrient accumulation, and grain yields of rice; and (2) elucidate the relationship between total nutrient accumulation and root morphologies under different shading conditions and nitrogen treatments. Three nitrogen rates, three shading treatments, and three different rice cultivars were used in two field experiments. Double shading during the grain-filling stage decreased total nutrient accumulation, altered root morphological characteristics, and decreased yields in rice. There were also significant interaction effects between nitrogen and shading on photosynthetic rate, transpiration rate, and total root length, root superficial area, and root volume. Significant interactions were found among cultivars and shading for photosynthetic rate and transpiration rate. Correlation analysis revealed that total nitrogen accumulation (TNA) and potassium accumulation (TKA) were significantly positively correlated with total root length, root superficial area, and root volume. N application could alleviate the detrimental effects of shading on total nutrient accumulation and grain yield in rice.

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

    SciTech Connect

    Lipps, F W

    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.

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

    SciTech Connect

    Lipps, F.W. )

    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.

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

    PubMed

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

    2011-03-01

    There are no consistent indications given by dental manufacturers on how to layer ceramics to achieve a color match to a shade selected from a dental shade guide. The technique for ceramic layering relies primarily on the skill and experience of ceramists and is not easily predictable. The purpose of this study was to evaluate, using a clinical spectrophotometer, the ability to color match shades selected with the 3D-Master shade guide using 2 different ceramic systems. Two ceramic systems were selected for this study, the VITA Omega 900 and VITA VM 13. For both systems, shades 2M3, 3M2, 4M2 of the VITA 3D-Master shade guide were selected. Thirty ceramic discs, 15 mm in diameter, were fabricated with different layer thickness ratios of opaque dentin, dentin, and enamel, maintaining a constant overall thickness. A clinical spectrophotometer (VITA Easyshade) was used for color comparison. The measured ΔE values were statistically analyzed with a 3-way ANOVA and the Tukey HSD test (α=.05). The 3-way ANOVA showed that the ceramic system (P<.001), the selected shade (P<.001), and the layering scheme all significantly influenced the ΔE values (P<.001). Both VITA VM 13 and VITA Omega 900 ceramic systems showed a color match with the shades 2M3, 3M2, and 4M2 of the VITA 3D-Master shade guide to be within the limits for clinical acceptability (ΔE≤ 3.3). VM 13 showed a statistically better color match. The layering scheme influenced the definitive color of the restoration. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  11. Effects of Shading on Cercospora Leaf Spot in Bigleaf Hydrangea

    USDA-ARS?s Scientific Manuscript database

    Shading densities significantly affected disease severities of Cercospora leaf spot on bigleaf hydrangeas. In general, lower disease severities were associated with higher shading densities. However, significantly differences in disease severities among cultivars could not be detected in higher sha...

  12. Effects of Shading on Cerospora Leaf Spot in Bigleaf Hydrangea

    USDA-ARS?s Scientific Manuscript database

    Shading densities significantly affected disease severities of Cercospora leaf spot on bigleaf hydrangeas. In general, lower disease severities were associated with higher shading densities. However, significantly differences in disease severities among cultivars could not be detected in higher sha...

  13. 5. HISTORIC PHOTOGRAPH, VIEW TO WHITE OAK SHADE ROAD BRIDGE, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. HISTORIC PHOTOGRAPH, VIEW TO WHITE OAK SHADE ROAD BRIDGE, CA. 1940. COLLECTION CONNECTICUT DEPARTMENT OF TRANSPORTATION. - Merritt Parkway, White Oak Shade Road Bridge, Spanning Merritt Parkway, New Canaan, Fairfield County, CT

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

    PubMed

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

    2016-01-01

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

  15. Shade tolerance and herbivory are associated with RGR of tree species via different functional traits.

    PubMed

    Salgado-Luarte, C; Gianoli, E

    2016-12-20

    Relative growth rate (RGR) plays an important role in plant adaptation to the light environment through the growth potential/survival trade-off. RGR is a complex trait with physiological and biomass allocation components. It has been argued that herbivory may influence the evolution of plant strategies to cope with the light environment, but little is known about the relation between susceptibility to herbivores and growth-related functional traits. Here, we examined in 11 evergreen tree species from a temperate rainforest the association between growth-related functional traits and (i) species' shade-tolerance, and (ii) herbivory rate in the field. We aimed at elucidating the differential linkage of shade and herbivory with RGR via growth-related functional traits. We found that RGR was associated negatively with shade-tolerance and positively with herbivory rate. However, herbivory rate and shade-tolerance were not significantly related. RGR was determined mainly by photosynthetic rate (Amax ) and specific leaf area (SLA). Results suggest that shade tolerance and herbivore resistance do not covary with the same functional traits. Whereas shade-tolerance was strongly related to Amax and to a lesser extent to leaf mass ratio (LMR) and dark respiration (Rd ), herbivory rate was closely related to allocation traits (SLA and LMR) and slightly associated with protein content. The effects of low light on RGR would be mediated by Amax , while the effects of herbivory on RGR would be mediated by SLA. Our findings suggest that shade and herbivores may differentially contribute to shape RGR of tree species through their effects on different resource-uptake functional traits.

  16. [Effects of soil moisture and shading levels on photosynthetic characteristics of cotton leaves].

    PubMed

    Liu, X; Kang, S; Shao, M; Wang, L

    2000-06-01

    The effects of different soil moistures and shading levels on stomatal conductance(Gs), net photosynthetic rates(Pn), transpiration and leaf water potential(LWP) of cotton (variety Zhongmian No. 23) grown in pots from the seedling to flower bud stages in summer noon were evaluated. We designed three shading levels: no-shading(CK), 75% shading (DN), 40% shading(SN); and three soil moistures; 85%-100% (high water, HW), 65%-85% (medium water, MW) and 45%-65% (low water, LW) of field water-bolding capacity. The Gs of DN and SN increased by 16.69% and 28.01% compared with CK at HW, respectively, while the Pn of DN and SN declined by 45.74% and 20.54%, respectively. The Gs of DN and SN enhanced by 28.86% and 23.28% compareds with CK at MW, respectively, while the Pn of DN and SN decreased by 31.97% and 1.64%, respectively. The Gs of CK, DN and Sn did not exhibit significant differences at LW, while Pn of DN and SN reduced by 46.22% and 13.45%, respectively. Significant difference in Gs did not exist between DN and SN at the same soil moisture, but there was significant difference in Pa between them (except at LW). It was suggested that Gs declined with the increasing of leaf-to-air vapor pressure difference (VPD) and showed weak correlation with Pn by regression. The combined effects of soil moistures and shading levels on LWP and transpiration rate were not significant. There was no significant difference in LWP and transpiration rate among three shading treatments. Contrasted to treatment CK, intercellular CO2 concentration (Ci) in DN and SN at HW, MW and LW increased significantly, except no apparent change of Ci in SN at MW.

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

    PubMed Central

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

    2016-01-01

    ABSTRACT Foraging time may be constrained by a suite of phenomena including weather, which can restrict a species' activity and energy intake. This is recognized as pivotal for many species whose distributions are known to correlate with climate, including kangaroos, although such impacts are rarely quantified. We explore how differences in shade seeking, a thermoregulatory behavior, of 2 closely-related kangaroo species, Macropus rufus (red kangaroos) and M. fuliginosus (western grey kangaroos), might reflect differences in their distributions across Australia. We observed foraging and shade-seeking behavior in the field and, together with local weather observations, calculated threshold radiant temperatures (based on solar and infrared radiant heat loads) over which the kangaroos retreated to shade. We apply these calculated tolerance thresholds to hourly microclimatic estimates derived from daily-gridded weather data to predict activity constraints across the Australian continent over a 10-year period. M. fuliginosus spent more time than M. rufus in the shade (7.6 ± 0.7 h versus 6.4 ± 0.9 h) and more time foraging (11.8 ± 0.5 h vs. 10.0 ± 0.6 h), although total time resting was equivalent (∼8.2 h). M. rufus tolerated 19°C higher radiant temperatures than M. fuliginosus (89°C versus 70°C radiant temperature). Across Australia, we predicted M. fuliginosus to be more restricted to shade than M. rufus, with higher absolute shade requirements farther north. These results corroborate previous findings that M. rufus is more adept at dealing with heat than M. fuliginosus and indicate that M. rufus is less dependent on shade on a continental scale. PMID:27857963

  18. Sap flow, gas exchange, and hydraulic conductance of young apricot trees growing under a shading net and different water supplies.

    PubMed

    Nicolás, Emilio; Torrecillas, Arturo; Dell'Amico, José; Alarcón, Juan José

    2005-04-01

    The experiment was carried out in a research field near Murcia, Spain, over a 3-week period between September 26 and October 16, 2000. Sixteen trees were used in the experiment, eight of which were placed under a rectangular shading net, while the other eight were maintained in the open air. Trees were irrigated once per day and, after October 5th, water was witheld from eight trees (four shaded and four unprotected for 5 days). The leaf stomatal conductance and the photosynthesis rates were higher in the shaded trees than in the exposed plants, probably because the leaf water potential was lower in the unshaded plants. This higher leaf conductance partially compensated for the effect of low radiation on transpiration, and the reduction of daily sap flow registered in shaded trees was only around 10-20%. The net also affected trunk diameter changes, with the shaded trees showing lower values of maximum daily shrinkage. Soil water deficit and high radiation had a similar effect on plant water parameters, lowering leaf water potential, leaf stomatal conductance, and the photosynthesis rate. The effects of both conditions were accumulative and so the exposed water-stressed plants showed the lowest values of total hydraulic resistance and water use efficiency, while the shaded well-irrigated trees registered the highest values for both parameters. For this reason, we think that net shading could be extended to apricot culture in many areas in which irrigation water is scarce and insolation is high.

  19. Shape from Shading in Starlings (Sturnus vulgaris)

    PubMed Central

    Qadri, Muhammad A.; Romero, L. Michael; Cook, Robert G.

    2014-01-01

    Birds behave as if they quickly and accurately perceive an object-filled visual world. Beyond the extensive research with pigeons, however, there is a large and important gap in our knowledge about the mechanisms of object perception and recognition in other avian visual systems. The pattern of shading reflected from object surfaces is one important optical feature providing fundamental information about shape. To better understand how surface and object shading is processed by a passerine species, five starlings were tested with differentially illuminated convex and concave curved surfaces in three experiments using a simultaneous visual discrimination procedure. Starlings rapidly learned this shape-from-shading discrimination independent of varied lighting direction, surface color, and camera perspective. Variations in the pattern of lighting through experimental manipulations of camera perspective, surface height, contrast, material specularity, and surface shape were consistent with the hypothesis that the starlings perceived these illuminated surfaces as having three-dimensional shape, similar to results previously collected with pigeons. These similarities across different orders of birds indicate that the relative shading for objects in a visual scene is a highly salient feature for shape processing in birds and is likely a highly conserved visual process that is widely distributed within this class of animal. PMID:25111630

  20. Illuminating the Mathematics of Lamp Shades

    ERIC Educational Resources Information Center

    Matthews, Michael E.; Gross, Greg

    2008-01-01

    The problem of creating lamp shades to specific design parameters allows rich and interesting explorations in the mathematics of circles and triangles. This interactive project helps students build their spatial reasoning and is especially appropriate during a unit on either the Pythagorean theorem or similar triangles. (Contains 7 figures and 1…

  1. 21 CFR 872.3690 - Tooth shade resin material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Tooth shade resin material. 872.3690 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3690 Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A...

  2. 21 CFR 872.3690 - Tooth shade resin material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  3. 21 CFR 872.3690 - Tooth shade resin material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Tooth shade resin material. 872.3690 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3690 Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A...

  4. 21 CFR 872.3690 - Tooth shade resin material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Tooth shade resin material. 872.3690 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3690 Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A...

  5. 21 CFR 872.3690 - Tooth shade resin material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Tooth shade resin material. 872.3690 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3690 Tooth shade resin material. (a) Identification. Tooth shade resin material is a device composed of materials such as bisphenol-A...

  6. Description of an exact recursive method to simplify shading calculations

    SciTech Connect

    Nawrocki, A.D.; Kammerud, R.

    1981-04-01

    An exact, recursive method called SHADE is described which attempts to simplify shading calculations as performed by a programmable calculator or microcomputer. Preliminary applications of SHADE using a Hewlett Packard HP-41C programmable calculation are outlined. In particular, for a given solar hour, SHADE is used to compute the following quantities for overhang and side fin combinations which shade various openings: the percentage of the total area of the opening which is shaded; the shaded area itself; the cosine of the angle of incidence between sun and glazing surface; the direct insolation at this surface, with and without shading; and the direct solar power at this surface, with and without shading. Hence, in its present HP-41C application, SHADE can be used in preliminary design and comparative analyses of shading devices on an hourly, daily, or seasonal basis, provided that: (1) the fins and overhangs be square or rectangular, and lie in planes perpendicular to the plane of the opening; and (2) the opening itself be vertical and rectangular with arbitrary building azimuths. Design candidates include conventional overhangs and side fins, porches, and reveals. In principle, SHADE can be extended to awnings, slatted sun screens, and bevelled recesses; in addition, its HP-41C application can be extended to calculations of direct solar gain through vertical and non-vertical glazings, thereby providing a more useful tool in building heating and cooling load calculations.

  7. Green light induces shade avoidance symptoms.

    PubMed

    Zhang, Tingting; Maruhnich, Stefanie A; Folta, Kevin M

    2011-11-01

    Light quality and quantity affect plant adaptation to changing light conditions. Certain wavelengths in the visible and near-visible spectrum are known to have discrete effects on plant growth and development, and the effects of red, far-red, blue, and ultraviolet light have been well described. In this report, an effect of green light on Arabidopsis (Arabidopsis thaliana) rosette architecture is demonstrated using a narrow-bandwidth light-emitting diode-based lighting system. When green light was added to a background of constant red and blue light, plants exhibited elongation of petioles and upward leaf reorientation, symptoms consistent with those observed in a shaded light environment. The same green light-induced phenotypes were also observed in phytochrome (phy) and cryptochrome (cry) mutant backgrounds. To explore the molecular mechanism underlying the green light-induced response, the accumulation of shade-induced transcripts was measured in response to enriched green light environments. Transcripts that have been demonstrated to increase in abundance under far-red-induced shade avoidance conditions either decrease or exhibit no change when green light is added. However, normal far-red light-associated transcript accumulation patterns are observed in cryptochrome mutants grown with supplemental green light, indicating that the green-absorbing form of cryptochrome is the photoreceptor active in limiting the green light induction of shade-associated transcripts. These results indicate that shade symptoms can be induced by the addition of green light and that cryptochrome receptors and an unknown light sensor participate in acclimation to the enriched green environment.

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

    PubMed

    Keller, Martha; Mustin, Walter

    2017-03-01

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

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

    PubMed

    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.

  10. SRTM Colored and Shaded Topography: Haro and Kas Hills, India

    NASA Image and Video Library

    2001-04-12

    On January 26, 2001, the Kachchh region in western India suffered the most deadly earthquake in India's history. This shaded topography view of landforms northeast of the city of Bhuj depicts geologic structures that are of interest in the study the tectonic processes that may have led to that earthquake. However, preliminary field studies indicate that these structures are composed of Mesozoic rocks that are overlain by younger rocks showing little deformation. Thus these structures may be old, not actively growing, and not directly related to the recent earthquake. The Haro Hills are on the left and the Kas Hills are on the right. The Haro Hills are an "anticline," which is an upwardly convex elongated fold of layered rocks. In this view, the anticline is distinctly ringed by an erosion resistant layer of sandstone. The east-west orientation of the anticline may relate to the crustal compression that has occurred during India's northward movement toward, and collision with, Asia. In contrast, the largest of the Kas Hills appears to be a tilted (to the south) and faulted (on the north) block of layered rocks. Also seen here, the linear feature trending toward the southwest from the image center is an erosion-resistant "dike," which is an igneous intrusion into older "host" rocks along a fault plane or other crack. These features are simple examples of how shaded topography can provide a direct input to geologic studies. In this image, colors show the elevation as measured by the Shuttle Radar Topography Mission (SRTM). Colors range from green at the lowest elevations, through yellow and red, to purple at the highest elevations. Elevations here range from near sea level to about 300 meters (about 1000 feet). Shading has been added, with illumination from the north (image top). http://photojournal.jpl.nasa.gov/catalog/PIA03300

  11. COP1 re-accumulates in the nucleus under shade.

    PubMed

    Pacín, Manuel; Legris, Martina; Casal, Jorge J

    2013-08-01

    Shade-avoider plants typically respond to shade-light signals by increasing the rate of stem growth. CONSTITTUTIVE PHOTOMORPHOGENESIS 1 (COP1) is an E3 ligase involved in the ubiquitin labelling of proteins targeted for degradation. In dark-grown seedlings, COP1 accumulates in the nucleus and light exposure causes COP1 migration to the cytosol. Here, we show that in Arabidopsis thaliana, COP1 accumulates in the nucleus under natural or simulated shade, despite the presence of far-red light. In plants grown under white light, the transfer to shade-light conditions triggers an unexpectedly rapid re-accumulation of COP1 in the nucleus. The partial simulation of shade by lowering either blue or red light levels (maintaining far-red light) caused COP1 nuclear re-accumulation. Hypocotyl growth of wild-type seedlings is more sensitive to afternoon shade than to morning shade. A residual response to shade was observed in the cop1 mutant background, but these seedlings showed inverted sensitivity as they responded to morning shade and not to afternoon shade. COP1 overexpression exaggerated the wild-type pattern by enhancing afternoon sensitivity and making morning shade inhibitory of growth. COP1 nuclear re-accumulation also responded more strongly to afternoon shade than to morning shade. These results are consistent with a signalling role of COP1 in shade avoidance. We propose a function of COP1 in setting the daily patterns of sensitivity to shade in the fluctuating light environments of plant canopies.

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

    PubMed

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

    2011-09-01

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

  13. Effect of coloured shade-nets on plant leaf parameters and tomato fruit quality.

    PubMed

    Ilić, Zoran S; Milenković, Lidija; Šunić, Ljubomir; Fallik, Elazar

    2015-10-01

    The concept of photo-selective netting using commercial cultivation practices was studied in a tomato (Solanum lycopersicum 'Vedetta') summer cultivation in south Serbia (under high solar radiation 910 W m(-2) , with a photosynthetic photon flux density of 1661 µmol m(-2) s(-1) ), under four different coloured shade-nets (pearl, red, blue and black) with 40% relative shading. The aim of the study was to determine how different environmental control technologies (coloured shade-nets as screen house or plastic-house integrated with coloured shade-nets) could influence plant parameters, production and quality traits in tomato fruits cultivated in south Serbia (Balkan region). The leaf area index (LAI) ranged from 4.6 to 5.8 in open field and plastic tunnels plants (control) with maximum LAI values of 7.9-8.2 in net houses with red colour nets. Shade-grown leaves generally have higher total chlorophyll and carotenoids content than do control leaves. Pericarp thickness was significantly higher tomatoes grown under pearl (7.215.82 µm), red (7099.00 µm) and blue nets (6802.29 µm) compared to other treatments and to control (6202.48 µm). The highest concentration of lycopene was detected in tomatoes grown in plastic houses integrated with red colour nets (64.9 µg g(-1) fresh weight). The plastic house and open field (control) tomato production had a taste index mean value of 1.09-1.10. This is significantly higher than the values determined for the treatments with different coloured shade-nets. These results show that red and pearl photo-selective nets create optimal growing conditions for the growth of the plant and produce fruits with thicker pericarp, the highest lycopene content, a satisfactory level of taste index and can be further implemented within protected cultivation practices. © 2014 Society of Chemical Industry.

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

    PubMed

    Schoonmaker, Amanda L; Lieffers, Victor J; Landhäusser, Simon M

    2014-01-01

    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.

  15. Uniform versus Asymmetric Shading Mediates Crown Recession in Conifers

    PubMed Central

    Schoonmaker, Amanda L.; Lieffers, Victor J.; Landhäusser, Simon M.

    2014-01-01

    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. PMID:25136823

  16. Shade tolerance, photoinhibition sensitivity and phenotypic plasticity of Ilex aquifolium in continental Mediterranean sites.

    PubMed

    Valladares, Fernando; Arrieta, Sagrario; Aranda, Ismael; Lorenzo, David; Sánchez-Gómez, David; Tena, David; Suárez, Francisco; Alberto Pardos, José

    2005-08-01

    Shade tolerance, plastic phenotypic response to light and sensitivity to photoinhibition were studied in holly (Ilex aquifolium L.) seedlings transported from the field to a greenhouse and in adult trees in the field. All plants were growing in, or originated from, continental Mediterranean sites in central Spain. Seedlings tolerated moderate but not deep shade. Mortality was high and growth reduced in 1% sunlight. Survival was maximal in 12% sunlight and minimal in full sunlight, although the relative growth rate of the seedlings surviving in high light was similar to that of plants in moderate shade. Maximum photochemical efficiency at predawn was significantly lower in sun plants than in shade plants in the field, revealing chronic photoinhibition that was most pronounced in winter. Plasticity in response to available light varied according to the variable studied, being low for photosynthetic capacity and stomatal conductance, and high for specific leaf area, root:shoot ratio and leaf area ratio, particularly in seedlings. Differences in water relations and hydraulic features between sun and shade plants in the field were marginal. High water potential at the turgor loss point of field-grown plants suggested that holly is sensitive to drought during both the seedling and the adult stage. Low relative growth rates in both high and low light with low physiological plasticity in response to light indicate the existence of a stress-tolerance mechanism. We conclude that holly is a facultative understory plant in areas of oceanic and relatively mild climate, but an obligate understory plant in dry continental areas such as the study site. The impact of abandonment of traditional management practices and climate change on these Mediterranean populations is discussed.

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

    PubMed

    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. Composite shade guides and color matching.

    PubMed

    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).

  19. Digital Shaded-Relief Image of Alaska

    USGS Publications Warehouse

    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

  20. Shape, Illumination, and Reflectance from Shading

    DTIC Science & Technology

    2013-05-29

    Shape, Illumination, and Reflectance from Shading Jonathan Barron Jitendra Malik Electrical Engineering and Computer Sciences University of...S) AND ADDRESS(ES) University of California at Berkeley, Electrical Engineering and Computer Sciences,Berkeley,CA,94720 8. PERFORMING ORGANIZATION...images [2], [3]. We will construct priors similar to those used � J.T. Barron and J. Malik are with the Department of Electrical Engi- neering and

  1. Heat stress interaction with shade and cooling.

    PubMed

    Armstrong, D V

    1994-07-01

    Hot weather causes heat stress in dairy cattle. Although effects are more severe in hot climates, dairy cattle in areas with relatively moderate climates also are exposed to periods of heat stress. The resultant decrease in milk production and reproductive efficiency can be offset by implementation of a program consisting of cooling through shades, ventilation and spray, and fans. The economic benefit should be determined before installation of equipment to reduce heat stress.

  2. Function of B-BOX under shade.

    PubMed

    Crocco, Carlos D; Holm, Magnus; Yanovsky, Marcelo J; Botto, Javier F

    2011-01-01

    Plants are capable of perceiving changes in the light environment and finely adjust their growth and development. Reductions of red to far-red ratio (R:FR) generated by an increase of the plant canopy above the plant are sensed by the phytochrome system triggering the shade-avoidance syndrome (SAS) that includes elongation of vegetative structures, reduction of branching and acceleration of flowering. Albeit the SAS is a strategy of major adaptative significance in plant communities, involving massive changes in gene expression, our knowledge of the SAS signaling network is still fragmented. By a selection and characterization of a T-DNA mutant with a long hypocotyl under shade, we identified BBX21, a protein with two B-box domains involved in the SAS. BBX21 belongs to a small eight member family of B-box containing proteins with both opposite and additive functions in the SAS signaling. BBX21 down-regulates the gene expression of auxin, brassinosteroid and ethylene signaling pathway components under shade. Furthermore BBX21 is a transcription factor that interacts genetically with COP1. We propose a model in which a dynamic balance of positive and negative B-box transcriptional regulators acts as a gas-and-brake mechanism into the COP1 signaling to regulate the expression of SAS.

  3. Shading, a view from the inside.

    PubMed

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

    2012-01-01

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

  4. Impact of Photovoltaic Canopy Shade on Outdoor Thermal Comfort in a Hot Desert City

    NASA Astrophysics Data System (ADS)

    Middel, Ariane; Selover, Nancy; Hagen, Björn; Chhetri, Nalini

    2016-04-01

    Shade plays an important role in designing pedestrian-friendly outdoor spaces in hot desert cities. This study investigates the impact of photovoltaic canopy shade on thermal comfort through microclimate observations and field surveys at a pedestrian mall on Arizona State University's Tempe campus. Six stationary sensors under solar canopies and in nearby sun-exposed and tree-shaded locations monitored 5-min temperature and humidity for a year. On selected clear calm days representative of each season, we conducted hourly microclimate transects from 7:00AM to 6:00PM and surveyed 1284 people about their thermal perception, comfort, and preferences. Shade lowered thermal sensation votes by approximately 1 point on the Likert scale, increasing thermal comfort in all seasons except winter. The shade type (tree or solar canopy) did not significantly impact perceived comfort, suggesting that artificial and natural shade are equally efficient in semi-arid desert environments. Globe temperature explained 50% of the variance in thermal sensation votes and was the only statistically significant meteorological predictor. Important non-meteorological factors include adaptation level, gender, thermal comfort vote, thermal preference, season, and time of day. A regression of perceived comfort 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 temperatures felt more comfortable if they had been in air-conditioning 5 minutes 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.

  5. Adjustments in epidermal UV-transmittance of leaves in sun-shade transitions.

    PubMed

    Barnes, Paul W; Kersting, Anna R; Flint, Stephan D; Beyschlag, Wolfram; Ryel, Ronald J

    2013-10-01

    Epidermal UV transmittance (TUV ) and UV-absorbing compounds were measured in sun and shade leaves of Populus tremuloides and Vicia faba exposed to contrasting light environments under field conditions to evaluate UV acclimation potentials and regulatory roles of photosynthetically active radiation (PAR) and UV in UV-shielding. Within a natural canopy of P. tremuloides, TUV ranged from 4 to 98% and showed a strong nonlinear relationship with mid-day horizontal fluxes of PAR [photon flux density (PFD) = 6-1830 µmol m⁻²  s⁻¹]; similar patterns were found for V. faba leaves that developed under a comparable PFD range. A series of field transfer experiments using neutral-density shade cloth and UV blocking/transmitting films indicated that PAR influenced TUV during leaf development to a greater degree than UV, and shade leaves of both species increased their UV-shielding when exposed to full sun; however, this required the presence of UV, with both UV-A and UV-B required for full acclimation. TUV of sun leaves of both species was largely unresponsive to shade either with or without UV. In most, but not all cases, changes in TUV were associated with alterations in the concentration of whole-leaf UV-absorbing compounds. These results suggest that, (1) moderate-to-high levels of PAR alone during leaf development can induce substantial UV-protection in field-grown plants, (2) mature shade leaves have the potential to adjust their UV-shielding which may reduce the detrimental effects of UV that could occur following sudden exposures to high light and (3) under field conditions, PAR and UV play different roles in regulating UV-shielding during and after leaf development.

  6. How cellulose-based leaf toughness and lamina density contribute to long leaf lifespans of shade-tolerant species.

    PubMed

    Kitajima, Kaoru; Llorens, Anna-Maria; Stefanescu, Carla; Timchenko, Marta Vargas; Lucas, Peter W; Wright, S Joseph

    2012-08-01

    Cell wall fibre and lamina density may interactively affect leaf toughness and leaf lifespan. Here, we tested this with seedlings of 24 neotropical tree species differing in shade tolerance and leaf lifespan under standardized field conditions (140-867 d in gaps; longer in shade). We quantified toughness with a cutting test, explicitly seeking a mechanistic linkage to fibre. Lamina density, but not fracture toughness, exhibited a plastic response to gaps vs shade, while neither trait was affected by leaf age. Toughness corrected for lamina density, a recently recognized indicator of material strength per unit mass, was linearly correlated with cellulose content per unit dry mass. Leaf lifespan was positively correlated with cellulose and toughness in shade-tolerant species but only weakly in gap-dependent species. Leaf lifespan was uncorrelated with lamina thickness, phenolics and tannin concentrations. In path analysis including all species, leaf lifespan was directly enhanced by density and toughness, and indirectly by cellulose via its effect on toughness. Different suites of leaf traits were correlated with early seedling survival in gaps vs shade. In conclusion, cellulose and lamina density jointly enhance leaf fracture toughness, and these carbon-based physical traits, rather than phenolic-based defence, explain species differences in herbivory, leaf lifespan and shade survival.

  7. Differential performance of tropical soda apple and its biological control agent Gratiana boliviana (Coleoptera: Chrysomelidae) in open and shaded habitats.

    PubMed

    Diaz, Rodrigo; Aguirre, Carlos; Wheeler, Gregory S; Lapointe, Stephen L; Rosskopf, Erin; Overholt, William A

    2011-12-01

    The leaf feeding beetle Gratiana boliviana Spaeth has been released since 2003 in the southeastern United States for biological control of tropical soda apple, Solanum viarum Dunal. In Florida, G. boliviana can be found on tropical soda apple growing in open pastures as well as in shady wooded areas. The objectives of this study were to determine the effect of light intensity on the performance of tropical soda apple and G. boliviana under greenhouse conditions, and to determine the abundance and mortality of G. boliviana in open and shaded habitats. Leaves growing in the shade were less tough, had higher water and nitrogen content, lower soluble sugars, and less dense and smaller glandular trichomes compared with leaves growing in the open. Plants grew slightly taller and wider under shaded conditions but total biomass was significantly reduced compared with plants grown in the open. In the greenhouse, G. boliviana had higher immature survival, greater folivory, larger adult size, and higher fecundity when reared on shaded plants compared with open plants. Sampling of field populations revealed that the overall abundance of G. boliviana was lower but leaf feeding damage was higher in shaded habitats compared with the open habitats. The percentage of eggs surviving to adult was greater in shaded compared with open habitats. The abundance of predators was higher in the open pasture and was positively correlated with the abundance of G. boliviana. These results indicate that not only plant quality but also habitat structure are important to the performance of weed biological control agents.

  8. Fine Shades of a Sombrero

    NASA Astrophysics Data System (ADS)

    2000-02-01

    In addition to their scientific value, many of the exposures now being obtained by visiting astronomers to ESO's Very Large Telescope (VLT) are also very beautiful. This is certainly true for this new image of the famous early-type spiral galaxy Messier 104 , widely known as the "Sombrero" (the Mexican hat) because of its particular shape. The colour image was made by a combination of three CCD images from the FORS1 multi-mode instrument on VLT ANTU , recently obtained by Peter Barthel from the Kapteyn Institute (Groningen, The Netherlands) during an observing run at the Paranal Observatory. He and Mark Neeser , also from the Kapteyn Institute, produced the composite images. The galaxy fits perfectly into the 6.8 x 6.8 arcmin 2 field-of-view of the FORS1 camera. A great amount of fine detail is revealed, from the structures in the pronounced dust band in the equatorial plane, to many faint background galaxies that shine through the outer regions. The "Sombrero" is located in the constellation Virgo (The Virgin), at a distance of about 50 million light-years. The overall "sharpness" of this colour image corresponds to about 0.7 arcsec which translates into a resolution of about 170 light-years at that distance. About Messier 104 Messier 104 is the 104th object in the famous catalogue of nebulae by French astronomer Charles Messier (1730 - 1817). It was not included in the first two editions (with 45 objects in 1774; 103 in 1781), but Messier soon thereafter added it by hand in his personal copy as a "very faint nebula". The recession velocity, about 1000 km/sec, was first measured by American astronomer Vesto M. Slipher at the Lowell Observatory in 1912; he was also the first to detect the galaxy's rotation. ESO Press Photo 07c/00 ESO Press Photo 07c/00 [Preview; JPEG: 400 x 307; 59k] [Normal; JPEG: 800 x 614; 308k] [Full-Res; JPEG: 2028 x 1556; 2.3Mb] PR Photo 07c/00 has been processed to show the numerous dust bands in the central plane of the Sombrero galaxy (see

  9. YUCCA auxin biosynthetic genes are required for Arabidopsis shade avoidance.

    PubMed

    Müller-Moulé, Patricia; Nozue, Kazunari; Pytlak, Melissa L; Palmer, Christine M; Covington, Michael F; Wallace, Andreah D; Harmer, Stacey L; Maloof, Julin N

    2016-01-01

    Plants respond to neighbor shade by increasing stem and petiole elongation. Shade, sensed by phytochrome photoreceptors, causes stabilization of PHYTOCHROME INTERACTING FACTOR proteins and subsequent induction of YUCCA auxin biosynthetic genes. To investigate the role of YUCCA genes in phytochrome-mediated elongation, we examined auxin signaling kinetics after an end-of-day far-red (EOD-FR) light treatment, and found that an auxin responsive reporter is rapidly induced within 2 hours of far-red exposure. YUCCA2, 5, 8, and 9 are all induced with similar kinetics suggesting that they could act redundantly to control shade-mediated elongation. To test this hypothesis we constructed a yucca2, 5, 8, 9 quadruple mutant and found that the hypocotyl and petiole EOD-FR and shade avoidance responses are completely disrupted. This work shows that YUCCA auxin biosynthetic genes are essential for detectable shade avoidance and that YUCCA genes are important for petiole shade avoidance.

  10. YUCCA auxin biosynthetic genes are required for Arabidopsis shade avoidance

    PubMed Central

    Müller-Moulé, Patricia; Nozue, Kazunari; Pytlak, Melissa L.; Palmer, Christine M.; Covington, Michael F.; Wallace, Andreah D.; Harmer, Stacey L.

    2016-01-01

    Plants respond to neighbor shade by increasing stem and petiole elongation. Shade, sensed by phytochrome photoreceptors, causes stabilization of PHYTOCHROME INTERACTING FACTOR proteins and subsequent induction of YUCCA auxin biosynthetic genes. To investigate the role of YUCCA genes in phytochrome-mediated elongation, we examined auxin signaling kinetics after an end-of-day far-red (EOD-FR) light treatment, and found that an auxin responsive reporter is rapidly induced within 2 hours of far-red exposure. YUCCA2, 5, 8, and 9 are all induced with similar kinetics suggesting that they could act redundantly to control shade-mediated elongation. To test this hypothesis we constructed a yucca2, 5, 8, 9 quadruple mutant and found that the hypocotyl and petiole EOD-FR and shade avoidance responses are completely disrupted. This work shows that YUCCA auxin biosynthetic genes are essential for detectable shade avoidance and that YUCCA genes are important for petiole shade avoidance. PMID:27761349

  11. Ambient ultraviolet radiation levels in public shade settings.

    PubMed

    Moise, A F; Aynsley, R

    1999-11-01

    As people become better informed about the harmful effects of prolonged exposure to solar ultraviolet radiation (UVR, 280-400 nm) they will seek the protection of shade, particularly in tropical locations such as Townsville (19 degrees south). Using broad-band radiation sensors for solar ultraviolet-B (280-315 nm), ultraviolet-A (315-400 nm) and daylight (400-800 nm) radiation, the exposure levels were measured in both the horizontal (shaded and unshaded) and vertical (shaded and unshaded) directions. The measurements were conducted at eight locations (shade settings) in Townsville during the period between December 1997 (summer) and May 1998 (beginning of winter). The quality of protection was assessed by the ratio of unshaded to shaded radiation exposure, the UVB/shade protection ratio (UVB-SPR). The UVB-SPR varies considerably between the different shade settings, with a beach umbrella showing the least protection and dense foliage the highest protection. The roof of a house verandah can provide only little protection if the verandah catches the afternoon sun. Increasing cloud cover decreases the UVB-SPR for all settings because of the increase in the diffuse fraction of the radiation. Only one setting provided a UVB-SPR of 15 or higher, as suggested for protective shading against solar UVB radiation. Shade from direct sunlight alone does not provide enough protection against high levels of solar UVR. Apart from the transmission qualities of the shading material, it is the construction of the whole shade setting that determines the exposure levels underneath. A shade structure with enough overhang is recommended so that high levels of scattered radiation do not reach the skin.

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

    PubMed

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

    2016-11-01

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

  13. Effect of Electron Shading on Gate Oxide Degradation

    NASA Astrophysics Data System (ADS)

    Sakamori, Shigenori; Maruyama, Takahiro; Fujiwara, Nobuo; Miyatake, Hiroshi

    1998-04-01

    The oxide degradation due to edge and electron shading effects is investigated in a pulse-modulated plasma using metal-oxide-silicon (MOS) and metal-nitride-oxide-silicon (MNOS) capacitors. Reduction of edge defect, shading defect and electron shading charge build-up is strongly dependent on the on-time in pulse plasma. In particular, when the on-time is shorter than 50 µs, the coefficient of the shading defect becomes almost zero. The investigation of MNOS capacitors, which have the patterns with or without the substrate contact antenna, indicates that the electric stress direction applied to gate oxide changes as the device structure changes.

  14. Digital shaded-relief map of Venezuela

    USGS Publications Warehouse

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

    2004-01-01

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

  15. Shaded Relief of Rio Sao Francisco, Brazil

    NASA Image and Video Library

    2000-02-14

    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. http://photojournal.jpl.nasa.gov/catalog/PIA02700

  16. Sinai Peninsula, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  17. Colored Height and Shaded Relief, Kamchatka Peninsula

    NASA Technical Reports Server (NTRS)

    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

  18. Bali, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  19. Sinai Peninsula, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  20. Bali, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  1. Preference for C4 shade grasses increases hatchling performance in the butterfly, Bicyclus safitza.

    PubMed

    Nokelainen, Ossi; Ripley, Brad S; van Bergen, Erik; Osborne, Colin P; Brakefield, Paul M

    2016-08-01

    The Miocene radiation of C4 grasses under high-temperature and low ambient CO 2 levels occurred alongside the transformation of a largely forested landscape into savanna. This inevitably changed the host plant regime of herbivores, and the simultaneous diversification of many consumer lineages, including Bicyclus butterflies in Africa, suggests that the radiations of grasses and grazers may be evolutionary linked. We examined mechanisms for this plant-herbivore interaction with the grass-feeding Bicyclus safitza in South Africa. In a controlled environment, we tested oviposition preference and hatchling performance on local grasses with C3 or C4 photosynthetic pathways that grow either in open or shaded habitats. We predicted preference for C3 plants due to a hypothesized lower processing cost and higher palatability to herbivores. In contrast, we found that females preferred C4 shade grasses rather than either C4 grasses from open habitats or C3 grasses. The oviposition preference broadly followed hatchling performance, although hatchling survival was equally good on C4 or C3 shade grasses. This finding was explained by leaf toughness; shade grasses were softer than grasses from open habitats. Field monitoring revealed a preference of adults for shaded habitats, and stable isotope analysis of field-sampled individuals confirmed their preference for C4 grasses as host plants. Our findings suggest that plant-herbivore interactions can influence the direction of selection in a grass-feeding butterfly. Based on this work, we postulate future research to test whether these interactions more generally contribute to radiations in herbivorous insects via expansions into new, unexploited ecological niches.

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

    PubMed

    Gustafsson, Camilla; Boström, Christoffer

    2013-01-01

    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.

  3. Positive effects of shade and shelter construction by ants on leafhopper-ant mutualism.

    PubMed

    Moya-Raygoza, Gustavo; Larsen, Kirk J

    2008-12-01

    The myrmecophilous five-spotted gamagrass leafhopper, Dalbulus quinquenotatus DeLong and Nault, and its tending ants on gamagrass Tripsacum dactyloides L. were examined to determine the influence of shade and ant-constructed shelters on the population sizes of D. quinquenotatus and ants. Gamagrass plants hosting ants and leafhoppers were exposed to 50, 30, or 0% artificially constructed shade. The greatest numbers of leafhoppers and ants were found on plants that received 50% shade. Shelters made by the ant Solenopsis geminata (F.) contained large numbers of leafhoppers and ants but were found only on T. dactyloides exposed to 50% shade in artificially constructed habitats. Additional sampling was conducted on wild gamagrass plants in the field to explore the presence of ants tending leafhoppers in shelters and to evaluate whether ant-constructed shelters protect leafhopper nymphs from parasitoid wasps. Large aggregations of S. geminata in shelters were also found in natural gamagrass habitats. Leafhopper nymphs living in shelters made by S. geminata may be protected against the dryinid wasp parasitoid Anteon ciudadi Olmi. No sheltered nymphs were parasitized by dryinids, whereas 24% of unsheltered nymphs had dryinid parasitism.

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    PubMed

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

    2017-04-01

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

  7. Vitamin D effective ultraviolet wavelengths due to scattering in shade.

    PubMed

    Turnbull, D J; Parisi, A V; Kimlin, M G

    2005-09-01

    Solar UVB radiation (280-320 nm) is an initiator of Vitamin D3 production in the human skin. While numerous studies have been conducted in relation to the biological impact of UV exposure in full sun, less research has investigated the irradiances in shade. The purpose of this study was to determine the levels of UV radiation in relation to Vitamin D3 induction with six commonly encountered shade environments for the larger solar zenith angles observed during autumn and winter. Spectral UV irradiance measurements were made under relatively clear sky conditions at a sub-tropical Southern Hemisphere site for six specific shade environments and solar zenith angle between 35 degrees and 60 degrees to investigate the biologically effective UV irradiances for pre-Vitamin D3 production. Data from this research indicates that pre-Vitamin D3 effective UV wavelengths in the shade were most significant for tree shade and a shade umbrella. Compared to that in full sun, pre-Vitamin D3 effective UV wavelengths were at levels of approximately 52 and 55%, respectively, beneath the shade umbrella and in tree shade. UVB irradiance levels in the shade of a northern facing covered veranda and in a car with windows closed were significantly less than those beneath the shade umbrella, with levels of approximately 11 and 0%, respectively, of those in full sun. Shade is important as a UV minimisation strategy; however, it may also play an important role in providing the human body with adequate levels of UVB radiation for pre-Vitamin D3 production without experiencing the relatively higher levels of UVA irradiances present in full sun.

  8. World Globes, Shaded Relief and Colored Height

    NASA Image and Video Library

    2003-08-21

    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. http://photojournal.jpl.nasa.gov/catalog/PIA03394

  9. Influence of shading on container-grown flowering dogwoods

    USDA-ARS?s Scientific Manuscript database

    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...

  10. AVIAN RESOURCE USE IN DOMINICAN SHADE COFFEE PLANTATIONS

    Treesearch

    JOSEPH M. WUNDERLE. JR; STEVEN C. LATTAA

    1998-01-01

    We quantified foraging behavior of 19 bird species in shade coffee plantations in the Dominican Republic to document and evaluate their use of food resources in the shade overstory relative to the coffee understory. All species were observed foraging in the Znga “era overstory, and 18 of the 19 species had median foraging heights significantly above the median maximum...

  11. Sky erythema ultraviolet radiance and UV shade charts

    NASA Astrophysics Data System (ADS)

    Kawanishi, Toshimasa

    2013-05-01

    The author developed electronic sweep type measurement equipment for sky erythema ultraviolet radiance. From the measurement results, UV Shade Charts were made expressing sky erythema radiance distribution as point density. Using the charts, the architectural sun protection factors (ASPFs) of shade were calculated.

  12. Shade effects on growth, flowering, and fruit of apple

    USDA-ARS?s Scientific Manuscript database

    Light is a critical resource needed by plants for growth and reproduction. A major portion of the apple (Malus xdomestica Borkh.) tree’s canopy is subjected to shade during most daylight hours each day and such shade may affect productivity. The current research determined effects of morning, afte...

  13. Shade material evaluation based on physiological response of cattle

    USDA-ARS?s Scientific Manuscript database

    Cattle produced in open feedlots are vulnerable to a variety of weather events; under certain conditions heat events can be especially detrimental. Shade structures are often considered as one method of reducing cattle stress. A variety of shading materials are available; selection of a suitable m...

  14. Computerized shade selection and the complex Class IV composite.

    PubMed

    Hovden, Kenneth

    2002-06-01

    By utilizing digital shade mapping, a stratified composite technique, and the proper composite system, the dental practitioner stands a greater chance of meeting patient expectations. In the case presented, the use of the Clear-Match system helped simplify shade selection, which is the greatest variable in success of anterior composite restorations.

  15. IMPROVING TALL FESCUE SHADE TOLERANCE: IDENTIFYING CANDIDATE GENOTYPES

    USDA-ARS?s Scientific Manuscript database

    Tall fescue (Schedonorus arundinaceus) is genetically variable for many agronomic traits, so it might be possible to increase its persistence and productivity in shaded agroforestry applications. The objective of this research was to identify high yielding, shade-tolerant genotypes. Seed was obtaine...

  16. Improving Tall Fescue Shade Tolerance: Identifying Candidate Genotypes

    USDA-ARS?s Scientific Manuscript database

    Tall fescue (Schedonorus arundinaceus) is genetically variable for many agronomic traits, so it might be possible to increase its persistence and productivity in shaded agroforestry applications. The objective of this research was to identify high yielding, shade-tolerant genotypes. Seed was obtai...

  17. Optimal integration of shading and binocular disparity for depth perception.

    PubMed

    Lovell, Paul G; Bloj, Marina; Harris, Julie M

    2012-01-01

    We explore the relative utility of shape from shading and binocular disparity for depth perception. Ray-traced images either featured a smooth surface illuminated from above (shading-only) or were defined by small dots (disparity-only). Observers judged which of a pair of smoothly curved convex objects had most depth. The shading cue was around half as reliable as the rich disparity information for depth discrimination. Shading- and disparity-defined cues where combined by placing dots in the stimulus image, superimposed upon the shaded surface, resulting in veridical shading and binocular disparity. Independently varying the depth delivered by each channel allowed creation of conflicting disparity-defined and shading-defined depth. We manipulated the reliability of the disparity information by adding disparity noise. As noise levels in the disparity channel were increased, perceived depths and variances shifted toward those of the now more reliable shading cue. Several different models of cue combination were applied to the data. Perceived depths and variances were well predicted by a classic maximum likelihood estimator (MLE) model of cue integration, for all but one observer. We discuss the extent to which MLE is the most parsimonious model to account for observer performance.

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

    PubMed Central

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

    2016-01-01

    Background and Objectives: 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. Methods: 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: 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. Conclusion: This in vitro study clearly delineates the advantages and limitations of both methods. There were significant differences between the methods with the visual method producing more accurate results than the spectrophotometric method. The spectrophotometer showed far better interrater agreement scores irrespective of the shade guide used. Even though visual shade matching is subjective, it is not inferior and should not be underrated. Judicious combination of both techniques is imperative to attain a successful and esthetic outcome. PMID:27746599

  19. Sapling leaf trait responses to light, tree height and soil nutrients for three conifer species of contrasting shade tolerance.

    PubMed

    Lilles, Erica B; Astrup, Rasmus; Lefrançois, Marie-Lou; David Coates, K

    2014-12-01

    We developed models to describe the responses of four commonly examined leaf traits (mass per area, weight, area and nitrogen (N) concentration) to gradients of light, soil nutrients and tree height in three conifer species of contrasting shade tolerance. Our observational dataset from the sub-boreal spruce forests of British Columbia included subalpine fir (Abies lasioscarpa [Hook.] Nutt; high shade tolerance), interior spruce (Picea glauca × Picea engelmannii [Moench] Voss; intermediate shade tolerance) and lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia; low shade tolerance) saplings from 0.18 to 4.87 m tall, in 8-98% of total incident light, from field sites with <17.6 kg ha(-1) to >46.8 kg ha(-1) total dissolved N. Leaf weights and areas showed strong positive responses to light and height, but little or no response to soil nutrients. Parameter estimates indicated that the shape of leaf weight and area responses to light corresponded with shade tolerance ranking for the three species; pine had the most linear response whereas spruce and fir had asymptotic responses. Leaf N concentration responded positively to soil nutrients, negatively to light and idiosyncratically to height. The negative effect of light was only apparent on sites of high soil nutrient availability, and parameter estimates for the shape of the negative response also corresponded to shade tolerance ranking (apine = -0.79, aspruce = -0.15, afir = -0.07). Of the traits we measured, leaf mass per area showed the least response to light, soil nutrient and height gradients. Although it is a common practice in comparisons across many species, characterizing these conifers by mean values of their leaf traits would miss important intraspecific variation across environmental and size gradients. In these forests, parameter estimates representing the intraspecific variability of leaf trait responses can be used to understand relative shade tolerances.

  20. Benefit of shading by nurse plant does not change along a stress gradient in a coastal dune.

    PubMed

    Castanho, Camila de Toledo; Prado, Paulo Inácio

    2014-01-01

    The proximity of adult neighbors often increases the performance of woody seedlings under harsh environmental conditions but this nurse plant effect becomes less intense when abiotic stress is alleviated, as predicted by the stress gradient hypothesis (SGH). Although some studies have tested how the net nurse effect is changed by stress, few studies have tested how the mechanism that drives the facilitative effect of nurse responds to changes in stress. We conducted field experiments in a subtropical coastal dune to test if shading drives the known nurse effect of adults of the tree Guapira opposita on seedling performance of another tree species, Ternstroemia brasiliensis. We transplanted T. brasiliensis seedlings to three neighbor environments: under a G. opposita crown, under artificial shade and without neighbor as a control. Furthermore, assuming that proximity to the seashore correlates with stress intensity, we tested if the potential shade-driven facilitation became less intense as stress decreased. Regardless of the proximity to the seashore, after a year, the survival of T. brasiliensis seedlings was twice as high when the seedlings were under G. opposita or under artificial shade compared to the control, indicating that the nurse effect is driven by shade and that this facilitation mechanism is constant along the stress gradient. However, G. opposita and artificial shade had a negative effect on seedlings growth. Overall, our results showed that the facilitation mechanism behind the nurse effect did not wane as the stress was reduced. Furthermore, in spite of the potential costs in terms of biomass production, our study highlights the potential of nurse plants and artificial shade as techniques to improve the survival of transplanted seedlings used in the restoration of degraded shrubland coastal dunes.

  1. Bayesian Depth-From-Defocus With Shading Constraints.

    PubMed

    Li, Chen; Su, Shuochen; Matsushita, Yasuyuki; Zhou, Kun; Lin, Stephen

    2016-02-01

    We present a method that enhances the performance of depth-from-defocus (DFD) through the use of shading information. DFD suffers from important limitations--namely coarse shape reconstruction and poor accuracy on textureless surfaces--that can be overcome with the help of shading. We integrate both forms of data within a Bayesian framework that capitalizes on their relative strengths. Shading data, however, is challenging to accurately recover from surfaces that contain texture. To address this issue, we propose an iterative technique that utilizes depth information to improve shading estimation, which in turn is used to elevate depth estimation in the presence of textures. The shading estimation can be performed in general scenes with unknown illumination using an approximate estimate of scene lighting. With this approach, we demonstrate improvements over existing DFD techniques, as well as effective shape reconstruction of textureless surfaces.

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

    PubMed

    Aengwanich, Worapol; Kongbuntad, Watee; Boonsorn, Thongchai

    2011-09-01

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

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

    NASA Astrophysics Data System (ADS)

    Aengwanich, Worapol; Kongbuntad, Watee; Boonsorn, Thongchai

    2011-09-01

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

  4. PowerFilm PowerShade Fixed Site Solar System Cost Reduction Plan

    DTIC Science & Technology

    2014-07-31

    2337 230’^ St Ames, lA 50014 JL’Olt^lO:pi𔄁oq7 j pageii Executive summary Power film and its partners have developed a Generation II PowerShade...years lifetime in the field. The life-cycle costs could be reduced significantly when this lifetime is increased to ten years. The photovoltaic ...design and improved manufacturing processes and flows. Improving the performance of the photovoltaic has the same impact by effectively increasing

  5. Ireland, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  6. Shaded Relief of Rio Sao Francisco, Brazil

    NASA Technical Reports Server (NTRS)

    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

  7. Shaded relief of Bahia State, Brazil

    NASA Technical Reports Server (NTRS)

    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

  8. World Globes, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  9. World Globes, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  10. Shaded Relief of Rio Sao Francisco, Brazil

    NASA Technical Reports Server (NTRS)

    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

  11. Shaded relief of Bahia State, Brazil

    NASA Technical Reports Server (NTRS)

    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

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

    PubMed

    Özat, P B; Tuncel, İ; Eroğlu, E

    2013-12-01

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

  13. Does shade improve light interception efficiency? A comparison among seedlings from shade-tolerant and -intolerant temperate deciduous tree species.

    PubMed

    Delagrange, Sylvain; Montpied, Pierre; Dreyer, Erwin; Messier, Christian; Sinoquet, Hervé

    2006-01-01

    Here, we tested two hypotheses: shading increases light interception efficiency (LIE) of broadleaved tree seedlings, and shade-tolerant species exhibit larger LIEs than do shade-intolerant ones. The impact of seedling size was taken into account to detect potential size-independent effects on LIE. LIE was defined as the ratio of mean light intercepted by leaves to light intercepted by a horizontal surface of equal area. Seedlings from five species differing in shade tolerance (Acer saccharum, Betula alleghaniensis, A. pseudoplatanus, B. pendula, Fagus sylvatica) were grown under neutral shading nets providing 36, 16 and 4% of external irradiance. Seedlings (1- and 2-year-old) were three-dimensionally digitized, allowing calculation of LIE. Shading induced dramatic reduction in total leaf area, which was lowest in shade-tolerant species in all irradiance regimes. Irradiance reduced LIE through increasing leaf overlap with increasing leaf area. There was very little evidence of significant size-independent plasticity of LIE. No relationship was found between the known shade tolerance of species and LIE at equivalent size and irradiance.

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

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

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

  15. The non-native plant Rosa multiflora expresses shade avoidance traits under low light availability.

    PubMed

    Dlugos, Daniel M; Collins, Hilary; Bartelme, Elise M; Drenovsky, Rebecca E

    2015-08-01

    Shade tolerance is a key trait promoting invasive plant performance in forest interiors. Rosa multiflora is a problematic invasive shrub in the northeastern United States, occurring in edge habitats and encroaching into forests. Our objective was to evaluate the shade tolerance of R. multiflora to assess how ecophysiological traits may facilitate its spread into forest interiors.• In the field, we documented shrub and seed bank density, fecundity, phenology, and seasonal photosynthetic rates of R. multiflora in contrasting light environments. In the greenhouse, we exposed seedlings to simulated canopy treatments by altering spectral quantity and quality, mimicking habitats ranging from open fields to forest interiors.• In the field, shrub density and fecundity of R. multiflora sharply increased with light availability. However, no differences were observed between forest edge and interior seed banks. Rosa multiflora initiated leaf growth earlier and retained leaves longer than canopy vegetation and tended to have higher photosynthetic rates in spring and fall. In the greenhouse, plants displayed shade-avoidance traits, decreasing relative growth rate and reducing branching, while increasing elongation and showing no change in light response curve parameters.• In deciduous forest understories, R. multiflora appears to make use of a lengthened growing season in spring and fall, and therefore, substantial growth and spread through intact forests appears dependent on canopy gaps. Management should focus on reducing edge populations to reduce spread into the interior and on monitoring newly created canopy gaps. © 2015 Botanical Society of America, Inc.

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

    PubMed Central

    Manimaran, P.; Sadan, D. Sai

    2016-01-01

    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. PMID:27829759

  17. Olduvai Gorge, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  18. Olduvai Gorge, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  19. American Samoa, Shaded Relief and Colored Height

    NASA Image and Video Library

    2009-10-01

    The topography of Tutuila, largest of the islands of American Samoa, is well shown in this color-coded perspective view generated with digital elevation data from the Shuttle Radar Topography Mission (SRTM.) The total area of Tutuila is about 141.8 square kilometers (54.8 square miles), slightly larger than San Francisco. The large bay near the center in this view is Pago Pago Harbor, actually a submerged volcanic crater whose south wall collapsed millions of years ago. Adjacent to the harbor is Pago Pago, the capital of American Samoa, and to the left (west) of the harbor in this view is Matafao Peak, Tutuila’s highest point at 653 meters (2,142 feet). On September 29, 2009, a tsunami generated by a major undersea earthquake located about 200 kilometers (120 miles) southwest of Tutuila inundated the more heavily populated southern coast of the island with an ocean surge more than 3 meters (10 feet) deep, causing scores of casualties. Digital topographic data such as those produced by SRTM aid researchers and planners in predicting which coastal regions are at the most risk from such waves, as well as from the more common storm surges caused by tropical storms and even sea level rise. Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shaded image was derived by computing topographic slope in the northeast-southwest direction, so that northeast slopes appear bright and southwest 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. The image was then projected using the elevation data to produce this perspective view, with the topography exaggerated by a factor of two. http://photojournal.jpl.nasa.gov/catalog/PIA11965

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

    PubMed

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

    2010-06-01

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

  1. Photovoltaic Shading Testbed for Module-Level Power Electronics

    SciTech Connect

    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.

  2. Plant adaptation to dynamically changing environment: the shade avoidance response.

    PubMed

    Ruberti, I; Sessa, G; Ciolfi, A; Possenti, M; Carabelli, M; Morelli, G

    2012-01-01

    The success of competitive interactions between plants determines the chance of survival of individuals and eventually of whole plant species. Shade-tolerant plants have adapted their photosynthesis to function optimally under low-light conditions. These plants are therefore capable of long-term survival under a canopy shade. In contrast, shade-avoiding plants adapt their growth to perceive maximum sunlight and therefore rapidly dominate gaps in a canopy. Daylight contains roughly equal proportions of red and far-red light, but within vegetation that ratio is lowered as a result of red absorption by photosynthetic pigments. This light quality change is perceived through the phytochrome system as an unambiguous signal of the proximity of neighbors resulting in a suite of developmental responses (termed the shade avoidance response) that, when successful, result in the overgrowth of those neighbors. Shoot elongation induced by low red/far-red light may confer high relative fitness in natural dense communities. However, since elongation is often achieved at the expense of leaf and root growth, shade avoidance may lead to reduction in crop plant productivity. Over the past decade, major progresses have been achieved in the understanding of the molecular basis of shade avoidance. However, uncovering the mechanisms underpinning plant response and adaptation to changes in the ratio of red to far-red light is key to design new strategies to precise modulate shade avoidance in time and space without impairing the overall crop ability to compete for light.

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

    Treesearch

    Kurt W. Gottschalk

    1994-01-01

    The study was conducted in an open field to detennine the optimum irradiance for establishment and growth of two oak species and two major associated woody species. Half-sib seedlings of black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and black oak (Q. velutina Lam.) were grown for two years under shade-clotht...

  4. Chlorophyll fluorescence kinetics, photosynthetic activity, and pigment composition of blue-shade and half-shade leaves as compared to sun and shade leaves of different trees.

    PubMed

    Lichtenthaler, Hartmut K; Babani, Fatbardha; Navrátil, Martin; Buschmann, Claus

    2013-11-01

    The chlorophyll (Chl) fluorescence induction kinetics, net photosynthetic CO2 fixation rates P N, and composition of photosynthetic pigments of differently light exposed leaves of several trees were comparatively measured to determine the differences in photosynthetic activity and pigment adaptation of leaves. The functional measurements were carried out with sun, half-shade and shade leaves of seven different trees species. These were: Acer platanoides L., Ginkgo biloba L., Fagus sylvatica L., Platanus x acerifolia Willd., Populus nigra L., Quercus robur L., Tilia cordata Mill. In three cases (beech, ginkgo, and oak), we compared the Chl fluorescence kinetics and photosynthetic rates of blue-shade leaves of the north tree crown receiving only blue sky light but no direct sunlight with that of sun leaves. In these cases, we also determined in detail the pigment composition of all four leaf types. In addition, we determined the quantum irradiance and spectral irradiance of direct sunlight, blue skylight as well as the irradiance in half shade and full shade. The results indicate that sun leaves possess significantly higher mean values for the net CO2 fixation rates P N (7.8-10.7 μmol CO2 m(-2) s(-1) leaf area) and the Chl fluorescence ratio R Fd (3.85-4.46) as compared to shade leaves (mean P N of 2.6-3.8 μmol CO2 m(-2) s(-1) leaf area.; mean R Fd of 1.94-2.56). Sun leaves also exhibit higher mean values for the pigment ratio Chl a/b (3.14-3.31) and considerably lower values for the weight ratio total chlorophylls to total carotenoids, (a + b)/(x + c), (4.07-4.25) as compared to shade leaves (Chl a/b 2.62-2.72) and (a + b)/(x + c) of 5.18-5.54. Blue-shade and half-shade leaves have an intermediate position between sun and shade leaves in all investigated parameters including the ratio F v/F o (maximum quantum yield of PS2 photochemistry) and are significantly different from sun and shade leaves but could not be differentiated from each other. The

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

    PubMed Central

    Behanam, Mohammed; Ahila, S.C.; Jei, J. Brintha

    2016-01-01

    Introduction Replication of natural skin colour in maxillofacial prosthesis has been traditionally done using trial and error method, as concrete shade guides are unavailable till date. Hence a novel custom made intrinsic silicone shade guide has been attempted for Indian population. Aim Reconstruction of maxillofacial defects is challenging, as achieving an aesthetic result is not always easy. A concoction of a novel intrinsic silicone shade guide was contemplated for the study and its reproducibility in clinical practice was analysed. Materials and Methods Medical grade room temperature vulcanising silicone was used for the fabrication of shade tabs. The shade guide consisted of three main groups I, II and III which were divided based upon the hues yellow, red and blue respectively. Five distinct intrinsic pigments were added in definite proportions to subdivide each group of different values from lighter to darker shades. A total number of 15 circular shade tabs comprised the guide. To validate the usage of the guide, visual assessment of colour matching was done by four investigators to investigate the consent of perfect colour correspondence. Data was statistically analysed using kappa coefficients. Results The kappa values were found to be 0.47 to 0.78 for yellow based group I, 0.13 to 0.65 for red based group II, and 0.07 to 0.36 for blue based group III. This revealed that the shade tabs of yellow and red based hues matched well and showed a statistically good colour matching. Conclusion This intrinsic silicone shade guide can be effectively utilised for fabrication of maxillofacial prosthesis with silicone in Indian population. A transparent colour formula with definite proportioning of intrinsic pigments is provided for obtaining an aesthetic match to skin tone. PMID:27190946

  6. Accurate shade image matching by using a smartphone camera.

    PubMed

    Tam, Weng-Kong; Lee, Hsi-Jian

    2017-04-01

    Dental shade matching by using digital images may be feasible when suitable color features are properly manipulated. Separating the color features into feature spaces facilitates favorable matching. We propose using support vector machines (SVM), which are outstanding classifiers, in shade classification. A total of 1300 shade tab images were captured using a smartphone camera with auto-mode settings and no flash. The images were shot at angled distances of 14-20cm from a shade guide at a clinic equipped with light tubes that produced a 4000K color temperature. The Group 1 samples comprised 1040 tab images, for which the shade guide was randomly positioned in the clinic, and the Group 2 samples comprised 260 tab images, for which the shade guide had a fixed position in the clinic. Rectangular content was cropped manually on each shade tab image and further divided into 10×2 blocks. The color features extracted from the blocks were described using a feature vector. The feature vectors in each group underwent SVM training and classification by using the "leave-one-out" strategy. The top one and three accuracies of Group 1 were 0.86 and 0.98, respectively, and those of Group 2 were 0.97 and 1.00, respectively. This study provides a feasible technique for dental shade classification that uses the camera of a mobile device. The findings reveal that the proposed SVM classification might outperform the shade-matching results of previous studies that have performed similarity measurements of ΔE levels or used an S, a*, b* feature set. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  7. Topographic Shading in the WRF Model with the Immersed Boundary Method: Implementation, Validation, and Application to Complex Terrain

    NASA Astrophysics Data System (ADS)

    Arthur, R. S.; Lundquist, K. A.; Mirocha, J. D.; Chow, F. K.

    2016-12-01

    In mountainous terrain, the diurnal variations of the surface sensible heat flux can lead to thermally-driven upslope and downslope flows during the daytime and nighttime, respectively. Topographic shading may influence these flows by limiting incoming solar radiation and creating large spatiotemporal inhomogeneities in the surface sensible heat flux. It is especially important to include topographic shading in high-resolution models of thermally-driven slope flows because of the effects it may have on flow development. In this work, the topographic shading algorithm in the Weather Research and Forecasting (WRF) model is coupled with the immersed boundary method (IBM). The IBM was originally implemented in WRF by Lundquist et al. (2010, 2012), and removes the restrictions on terrain slope that are associated with WRF's traditional terrain-following vertical coordinate, permitting high-resolution atmospheric simulations over complex terrain. The topographic shading implementation is validated by comparing shadow location, land-surface fluxes, and temperature and velocity fields between idealized WRF simulations both with and without the IBM. Following validation, the topographic shading implementation is tested in a realistic simulation of Granite Mountain, Utah, where topographic shading is known to affect downslope flow development in the evening (Fernando et al. 2015). The horizontal resolution of the model is 50 m and the vertical resolution is approximately 10 m near the surface, which would be infeasible in a standard WRF model with terrain-following coordinates due to large local slope values reaching roughly 55 degrees. The development of downslope flows after local sunset in the model is discussed and shown to be consistent with field observations from the Mountain Terrain Atmospheric Modeling and Observations (MATERHORN) project.

  8. Computer-generated holograms for three-dimensional surface objects with shade and texture.

    PubMed

    Matsushima, Kyoji

    2005-08-01

    Digitally synthetic holograms of surface model objects are investigated for reconstructing three-dimensional objects with shade and texture. The objects in the proposed techniques are composed of planar surfaces, and a property function defined for each surface provides shape and texture. The field emitted from each surface is independently calculated by a method based on rotational transformation of the property function by use of a fast Fourier transform (FFT) and totaled on the hologram. This technique has led to a reduction in computational cost: FFT operation is required only once for calculating a surface. In addition, another technique based on a theoretical model of the brightness of the reconstructed surfaces enables us to shade the surface of a reconstructed object as designed. Optical reconstructions of holograms synthesized by the proposed techniques are demonstrated.

  9. Do Shallow Cumulus Clouds have the Potential to Trigger Secondary Circulations Via Shading?

    NASA Astrophysics Data System (ADS)

    Gronemeier, Tobias; Kanani-Sühring, Farah; Raasch, Siegfried

    2017-01-01

    The effects on the convective boundary layer (CBL) of shading due to shallow cumulus clouds are investigated. The main question is to see whether clouds are able to produce secondary circulations by shading of the surface (dynamic heterogeneities) and how these dynamic heterogeneities interact with static heterogeneities in terms of the production of secondary circulations. Also the effects of cloud shadows on cloud-field characteristics are analyzed. The effects are studied using large-eddy simulations of a cloud-topped CBL with an idealized surface. Over a homogeneous surface, shadows trigger secondary circulations with different strengths depending on the solar zenith angle θ, with large θ favouring the development of secondary circulations. Over a static heterogeneous surface with a simple striped pattern, the strength of secondary circulations is effectively reduced by dynamic heterogeneities at small θ. At large θ, however, the effect on secondary circulations depends on the orientation of the striped static heterogeneities to the shadow-casting direction of the clouds. The influence of shadows is only small if they are cast perpendicular to the striped heterogeneity, but if stripes and the shadow-casting direction are parallel, secondary circulations are reduced in strength also for large θ. Shadow effects on the cloud-field characteristics vary with θ as well. The results show that small θ favours the development of small clouds with a reduced lifetime while large θ promotes the development of larger clouds with an extended lifetime compared to non-shading clouds.

  10. The shade avoidance syndrome in Arabidopsis: the antagonistic role of phytochrome a and B differentiates vegetation proximity and canopy shade.

    PubMed

    Martínez-García, Jaime F; Gallemí, Marçal; Molina-Contreras, María José; Llorente, Briardo; Bevilaqua, Maycon R R; Quail, Peter H

    2014-01-01

    Light limitation caused by dense vegetation is one of the greatest threats to plant survival in natural environments. Plants detect such neighboring vegetation as a reduction in the red to far-red ratio (R:FR) of the incoming light. The low R:FR signal, perceived by phytochromes, initiates a set of responses collectively known as the shade avoidance syndrome, intended to reduce the degree of current or future shade from neighbors by overtopping such competitors or inducing flowering to ensure seed production. At the seedling stage these responses include increased hypocotyl elongation. We have systematically analyzed the Arabidopsis seedling response and the contribution of phyA and phyB to perception of decreased R:FR, at three different levels of photosynthetically active radiation. Our results show that the shade avoidance syndrome, induced by phyB deactivation, is gradually antagonized by phyA, operating through the so-called FR-High Irradiance Response, in response to high FR levels in a range that simulates plant canopy shade. The data indicate that the R:FR signal distinguishes between the presence of proximal, but non-shading, neighbors and direct foliar shade, via a intrafamily photosensory attenuation mechanism that acts to suppress excessive reversion toward skotomorphogenic development under prolonged direct vegetation shade.

  11. [Analysis of the color difference between discolored teeth and corresponding shade tabs in Vitapan Classical shade guide].

    PubMed

    Xu, Yingxin

    2015-08-01

    To analyze whether Vitapan Classical shade guide could be used to evaluate effectively the effect of tooth whitening. A total of 67 patients underwent Beyond cold light tooth whitening between February 2009 and July 2014. The effect of treatment was evaluated by Vitapan Classical shade guide. The percentage of discolored teeth that could not be matched by the aforementioned shade guide was calculated. By contrast, the color difference between discolored teeth and corresponding shade tabs was calculated for discolored teeth that could be matched by the shade guide. Approximately 64% (16/25) of tetracycline teeth and 28% (17/61) of mottled-enamel teeth could not be matched using the Vitapan Classical shade guide, but yellow teeth were all matched, and the difference between any pair of teeth was statistically significant (P=0.000). For discolored teeth that could be matched, statistically significant difference was found in the ΔL*, Δb*, and ΔE between tetracycline and yellow teeth, as well as between tetracycline and mottled-enamel teeth. However, no statistically significant difference was found between mottled-enamel and yellow teeth. Moreover, no statistically significant difference was found in the Δa* among the three groups. Vitapan Classical shade guide could not be used to evaluate effectively the effect of tooth whitening, especially for tetracycline and mottled-enamel teeth. The evaluating method should be improved.

  12. Guiana Highlands, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2003-01-01

    inspiration for Arthur Conan Doyle's 1912 best-seller 'The Lost 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.

    Location: 0.2 South to 8.7 degrees North latitude, 60 to 67.9 degrees West longitude Orientation: North toward the top Image Data: shaded and colored SRTM30 and GTOPO30 elevation models Data Resolution: SRTM 30 arcsecond (about 928 meters or 1496 feet) Date Acquired: February 2000 for SRTM

  13. Australia, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    : 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: 45 to 10 degrees South latitude, 112 to 155 degrees East longitude Orientation: North toward the top, Mercator projection Image Data: shaded and colored SRTM elevation model Date Acquired: February 2000

  14. France, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  15. France, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    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

  16. Colored Height and Shaded Relief, Central America

    NASA Technical Reports Server (NTRS)

    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

  17. Australia, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    : 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: 45 to 10 degrees South latitude, 112 to 155 degrees East longitude Orientation: North toward the top, Mercator projection Image Data: shaded and colored SRTM elevation model Date Acquired: February 2000

  18. Guiana Highlands, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2003-01-01

    inspiration for Arthur Conan Doyle's 1912 best-seller 'The Lost 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.

    Location: 0.2 South to 8.7 degrees North latitude, 60 to 67.9 degrees West longitude Orientation: North toward the top Image Data: shaded and colored SRTM30 and GTOPO30 elevation models Data Resolution: SRTM 30 arcsecond (about 928 meters or 1496 feet) Date Acquired: February 2000 for SRTM

  19. Shaded relief, color as height Patagonia, Argentina

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This topographic image of Patagonia, Argentina shows a spectacular landscape formed by volcanoes, rivers, and wind. The area is located just east of the narrow range of the Andes Mountains, about 100 kilometers (62 miles) east of the border with Chile. Interesting features include basalt-capped mesas with sinkholes (lower center), arcuate ridges of windblown beach sands downwind from a salty desert lake (upper center), young volcanic cones(right), and at least one case of what geologists call 'inverted relief'. This happens when lava flows down a valley in soft material and then the soft material is eroded away leaving the former valley as a ridge of lava. These ridges can be seen on the slopes of the volcano in the upper right. Geologists will use SRTM topographic data to study the interaction of volcanic, climatic and erosional processes.

    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 1100 meters(3600 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

  20. Shaded relief, color as height Patagonia, Argentina

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This topographic image of Patagonia, Argentina shows a spectacular landscape formed by volcanoes, rivers, and wind. The area is located just east of the narrow range of the Andes Mountains, about 100 kilometers (62 miles) east of the border with Chile. Interesting features include basalt-capped mesas with sinkholes (lower center), arcuate ridges of windblown beach sands downwind from a salty desert lake (upper center), young volcanic cones(right), and at least one case of what geologists call 'inverted relief'. This happens when lava flows down a valley in soft material and then the soft material is eroded away leaving the former valley as a ridge of lava. These ridges can be seen on the slopes of the volcano in the upper right. Geologists will use SRTM topographic data to study the interaction of volcanic, climatic and erosional processes.

    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 1100 meters(3600 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

  1. Gulf Coast, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2

    The topography of the Gulf Coast states is well shown in this color-coded shaded relief map generated with data from the Shuttle Radar Topography Mission. The image on the top (see Figure 1) is a standard view showing southern Louisiana, Mississippi, Alabama and the panhandle of Florida. Green colors indicate low elevations, rising through yellow and tan, to white at the highest elevations.

    For the view on the bottom (see Figure 2), elevations below 10 meters (33 feet) above sea level have been colored light blue. These low coastal elevations are especially vulnerable to flooding associated with storm surges. Planners can use data like these to predict which areas are in the most danger and help develop mitigation plans in the event of particular flood events.

    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 Science Mission Directorate, Washington, D.C.

    Location: 31 degrees north latitude, 88 degrees west longitude Orientation: North toward the top, Mercator projection Size: 702 by 433 kilometers (435 by 268 miles) Image Data: shaded and colored SRTM

  2. Southern Florida, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The very low topography of southern Florida is evident in this color-coded shaded relief map generated with data from the Shuttle Radar Topography Mission. The image on the left is a standard view, with the green colors indicating low elevations, rising through yellow and tan, to white at the highest elevations. In this exaggerated view even those highest elevations are only about 60 meters (197 feet) above sea level.

    For the view on the right, elevations below 5 meters (16 feet) above sea level have been colored dark blue, and lighter blue indicates elevations below 10 meters (33 feet). This is a dramatic demonstration of how Florida's low topography, especially along the coastline, make it especially vulnerable to flooding associated with storm surges. Planners can use data like these to predict which areas are in the most danger and help develop mitigation plans in the event of particular flood events.

    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 Science Mission Directorate, Washington, D.C.

    Location: 27 degrees north latitude, 81 degrees west longitude Orientation: North toward the top, Mercator projection Size: 397 by 445 kilometers (246 by 276 miles) Image

  3. Gulf Coast, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2

    The topography of the Gulf Coast states is well shown in this color-coded shaded relief map generated with data from the Shuttle Radar Topography Mission. The image on the top (see Figure 1) is a standard view showing southern Louisiana, Mississippi, Alabama and the panhandle of Florida. Green colors indicate low elevations, rising through yellow and tan, to white at the highest elevations.

    For the view on the bottom (see Figure 2), elevations below 10 meters (33 feet) above sea level have been colored light blue. These low coastal elevations are especially vulnerable to flooding associated with storm surges. Planners can use data like these to predict which areas are in the most danger and help develop mitigation plans in the event of particular flood events.

    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 Science Mission Directorate, Washington, D.C.

    Location: 31 degrees north latitude, 88 degrees west longitude Orientation: North toward the top, Mercator projection Size: 702 by 433 kilometers (435 by 268 miles) Image Data: shaded and colored SRTM

  4. Southern Florida, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The very low topography of southern Florida is evident in this color-coded shaded relief map generated with data from the Shuttle Radar Topography Mission. The image on the left is a standard view, with the green colors indicating low elevations, rising through yellow and tan, to white at the highest elevations. In this exaggerated view even those highest elevations are only about 60 meters (197 feet) above sea level.

    For the view on the right, elevations below 5 meters (16 feet) above sea level have been colored dark blue, and lighter blue indicates elevations below 10 meters (33 feet). This is a dramatic demonstration of how Florida's low topography, especially along the coastline, make it especially vulnerable to flooding associated with storm surges. Planners can use data like these to predict which areas are in the most danger and help develop mitigation plans in the event of particular flood events.

    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 Science Mission Directorate, Washington, D.C.

    Location: 27 degrees north latitude, 81 degrees west longitude Orientation: North toward the top, Mercator projection Size: 397 by 445 kilometers (246 by 276 miles) Image

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

    Treesearch

    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...

  6. Why are evergreen leaves so contrary about shade?

    PubMed

    Lusk, Christopher H; Reich, Peter B; Montgomery, Rebecca A; Ackerly, David D; Cavender-Bares, Jeannine

    2008-06-01

    Leaf mass per area (LMA) is one of the most widely measured of all plant functional traits. In deciduous forests, there is similarity between plastic and evolutionary responses of LMA to light gradients. In evergreens, however, LMA is lower in shaded than sunlit individuals of the same species, whereas shade-tolerant evergreens have higher LMA than light-demanders grown under the same conditions. We suggest that this pattern of 'counter-gradient variation' results from some combination of (i) close evolutionary coordination of LMA with leaf lifespan, (ii) selection for different leaf constitutions (relative investment in cell walls versus cell contents) in sun and shade environments and/or (iii) constraints on plasticity as a result of genetic correlations between phenotypes expressed in sun and shade.

  7. View from Shade Gap extension of Rockhill Trolley Museum grounds ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from Shade Gap extension of Rockhill Trolley Museum grounds with Orbisonia Station at extreme right - East Broad Top Railroad & Coal Company, State Route 994, West of U.S. Route 522, Rockhill Furnace, Huntingdon County, PA

  8. Photoreceptor signaling networks in plant responses to shade.

    PubMed

    Casal, Jorge J

    2013-01-01

    The dynamic light environment of vegetation canopies is perceived by phytochromes, cryptochromes, phototropins, and UV RESISTANCE LOCUS 8 (UVR8). These receptors control avoidance responses to preclude exposure to limiting or excessive light and acclimation responses to cope with conditions that cannot be avoided. The low red/far-red ratios of shade light reduce phytochrome B activity, which allows PHYTOCHROME INTERACTING FACTORS (PIFs) to directly activate the transcription of auxin-synthesis genes, leading to shade-avoidance responses. Direct PIF interaction with DELLA proteins links gibberellin and brassinosteroid signaling to shade avoidance. Shade avoidance also requires CONSTITUTIVE PHOTOMORPHOGENESIS 1 (COP1), a target of cryptochromes, phytochromes, and UVR8. Multiple regulatory loops and the input of the circadian clock create a complex network able to respond even to subtle threats of competition with neighbors while still compensating for major environmental fluctuations such as the day-night cycles.

  9. Evaluation of the Aurora Application Shade Measurement Accuracy

    SciTech Connect

    2015-12-01

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

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

    EPA Science Inventory

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

  11. 51. (no plate) Lens, lens pedestal, mercury float, shade holder ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    51. (no plate) Lens, lens pedestal, mercury float, shade holder installation, drawing # 3101, sheet 2 of 2. Approved April 6, 1928. - Block Island Southeast Light, Spring Street & Mohegan Trail at Mohegan Bluffs, New Shoreham, Washington County, RI

  12. Facilitation of shape-from-shading perception by random textures

    NASA Astrophysics Data System (ADS)

    Sakai, Ko; Narushima, Kazuki; Aoki, Natsuko

    2006-08-01

    Most natural objects have a texture on their surface, so the segregation between shading and texture is crucial for the robust perception of three-dimensional structure: The visual system has to decide whether shading or texture evoked the luminance change. We found that the contextual pop-out that results from shading was not suppressed, but was even facilitated, when random texture was added to the luminance of the entire stimulus, indicating the functional segregation and facilitative interaction between shading and texture cues. The local contrast evoked by random texture within a figure or at a boundary was a major factor in the facilitation, suggesting the crucial role of early vision in the interaction between the cues.

  13. Determination of the Solar Ultraviolet Transmission in Tree Shade.

    ERIC Educational Resources Information Center

    Parisi, Alfio V.; Kimlin, Michael G.

    1999-01-01

    Presents an activity in which the amount of solar ultraviolet radiation in tree shade is measured at different times of the day and compared with changes in illumination levels and temperature. (Author/WRM)

  14. Shading and shadowing on Canaletto's Piazza San Marco

    NASA Astrophysics Data System (ADS)

    Wijntjes, Maarten W. A.; de Ridder, Huib

    2014-02-01

    Whereas the 17th century painter Canaletto was a master in linear perspective of the architectural elements, he seems to have had considerable difficulty with linear perspective of shadows. A common trick to avoid shadow perspective problems is to set the (solar) illumination direction parallel to the projection screen. We investigated in one painting where Canaletto clearly used this trick, whether he followed this light direction choice consistently through in how he shades the persons. We approached this question with a perceptual experiment where we measured perceived light directions in isolated details of the paintings. Specifically, we controlled whether observers could only see the (cast) shadow, only shading or both. We found different trends in all three conditions. The results indicate that Canaletto probably used different shading than the parallel light direction would predict. We interpret the results as a form or artistic freedom that Canaletto used to shade the persons individually.

  15. Shade images of forested areas obtained from Landsat MSS data

    NASA Technical Reports Server (NTRS)

    Shimabukuro, Yosio Edemir; Smith, James A.

    1989-01-01

    The objective of this report is to generate a shade (shadow) image of forested areas from Landsat MSS data by implementing a linear mixing model, where shadow is considered as one of the primary components in a pixel. The shade images are related to the observed variation in forest structure; i.e., the proportion of inferred shadow in a pixel is related to different forest ages, forest types, and tree crown cover. The constrained least-squares method is used to generate shade images for forest of eucalyptus and vegetation of 'cerrado' over the Itapeva study area in Brazil. The resulted shade images may explain the difference on ages for forest of eucalyptus and the difference on tree crown cover for vegetation of cerrado.

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

    EPA Science Inventory

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

  17. Two simple tools for design of fixed shades

    SciTech Connect

    Nawrocki, D.; Andersson, B.; Kammerud, R.

    1980-01-01

    Two methods to assist designers in selecting and evaluating fixed, rectangular shading devices for rectangular wall and roof apertures early in the design process are presented. Both methods are based upon a simple mathematical technique called SHADE. The first method is visual, using graphics prepared in advance by a computer program and the existing Libby-Owens-Ford Sun Angle Calculators to design appropriate shading during early stages of architectural design. The second method uses a Hewlett Packard 41C programmable calculator to refine the design by analysis of shading effects at specific hours, and to generate numerical data for use with detiled hand calculations of building loads. Each method is described, its advantages are noted, and an example of the use of each is given. Possible extensions and potential applications are discussed.

  18. TWO SIMPLE TOOLS FOR DESIGN OF FIXED SHADES

    SciTech Connect

    Nawrocki, Dave; Andersson, Brandt; Kammerud, Ronald

    1980-10-01

    Two methods to assist designers in selecting and evaluating fixed, rectangular shading devices for rectangular wall and roof apertures early in the design process are presented. Both methods are based upon a simple mathematical technique called SHADE. The first method is visual, using graphics prepared in advance by a computer program and the existing Libby-Owens-Ford Sun Angle Calculator to design appropriate shading during early stages of architectural design. The second method uses a Hewlett Packard 41C programmable calculator to refine the design by analysis of shading effects at specific hours, and to generate numerical data for use with detailed hand calculations of building loads. Each method is described, its advantages are noted, and an example of the use of each is given. Possible extensions and potential applications are discussed.

  19. DETAIL OF CORNICE MOULDING WITH RAM'S HEAD MOTIF. EIGHT SHADES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF CORNICE MOULDING WITH RAM'S HEAD MOTIF. EIGHT SHADES OF GOLD LEAF AND BURNISHED GOLD LEAF WERE USED FOR THE INTERIOR FINISHES. - Anaconda Historic District, Washoe Theater, 305 Main Street, Anaconda, Deer Lodge County, MT

  20. Africa in SRTM 3-D, Anaglyph of Shaded Relief

    NASA Image and Video Library

    2004-06-17

    This stereoscopic shaded relief image from NASA Shuttle Radar Topography Mission shows Africa topography. Also shown are Madagascar, the Arabian Peninsula, and other adjacent regions. 3D glasses are necessary to view this image.

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

    NASA Image and Video Library

    2003-03-06

    This shaded relief image of Mexico 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.

  2. Shaded-Color Picture Generation of Computer-Defined Arbitrary Shapes

    NASA Technical Reports Server (NTRS)

    Cozzolongo, J. V.; Hermstad, D. L.; Mccoy, D. S.; Clark, J.

    1986-01-01

    SHADE computer program generates realistic color-shaded pictures from computer-defined arbitrary shapes. Objects defined for computer representation displayed as smooth, color-shaded surfaces, including varying degrees of transparency. Results also used for presentation of computational results. By performing color mapping, SHADE colors model surface to display analysis results as pressures, stresses, and temperatures. NASA has used SHADE extensively in sign and analysis of high-performance aircraft. Industry should find applications for SHADE in computer-aided design and computer-aided manufacturing. SHADE written in VAX FORTRAN and MACRO Assembler for either interactive or batch execution.

  3. Shaded-Color Picture Generation of Computer-Defined Arbitrary Shapes

    NASA Technical Reports Server (NTRS)

    Cozzolongo, J. V.; Hermstad, D. L.; Mccoy, D. S.; Clark, J.

    1986-01-01

    SHADE computer program generates realistic color-shaded pictures from computer-defined arbitrary shapes. Objects defined for computer representation displayed as smooth, color-shaded surfaces, including varying degrees of transparency. Results also used for presentation of computational results. By performing color mapping, SHADE colors model surface to display analysis results as pressures, stresses, and temperatures. NASA has used SHADE extensively in sign and analysis of high-performance aircraft. Industry should find applications for SHADE in computer-aided design and computer-aided manufacturing. SHADE written in VAX FORTRAN and MACRO Assembler for either interactive or batch execution.

  4. Color Shade Instrumentation Correlation Study: Statistical Analysis. Revision

    DTIC Science & Technology

    2011-03-01

    preserve the anonymity of the spectrophotometer manufacturers, each manufacturer is represented by a letter from the Hebrew alphabet: Aleph, Beth, Gimel...however, current shade acceptance of military textile materials to a shade standard is strictly based on visual assess- ment methods. Visual evaluation...were based on stan- dards commonly used by government and industry. These standards are based on the International Commission on Illumination (CIE, or

  5. Photosynthesis and Biomass Allocation in Oak Seedlings Grown Under Shade

    Treesearch

    Shi-Jean S. Sung; Paul P. Kormanik; Stanley J. Zarnoch

    1998-01-01

    Abstract-Northern red oak (Quercus rubra L.) (NRO) and white oak (Q. alba L.) (WO) acorns were sown into wooden plots and grown under 30 percent shade screen (30 percent S) or 70 percent shade screen (70 percent S). Seedlings grown under full sun were the controls (C). At the end of the first year, the 30 percent S NRO had 30 percent greater seedling dry weight (DW...

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

    PubMed

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

    2014-09-01

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

  7. Shade response of a full size TESSERA module

    NASA Astrophysics Data System (ADS)

    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.

  8. Electron shading on a macroscopic scale

    NASA Astrophysics Data System (ADS)

    Madziwa, Tsitsi G.; Chen, Francis F.

    2000-10-01

    Damage to thin gate insulators during plasma processing is thought to be caused by the electron shading effect, in which a negative charge on the photoresist prevents electrons from reaching the bottoms of trenches and vias. The resulting positive charge impinging on the oxide layer creates megavolt potentials across it. Though this hypothetical effect has been modeled extensively in computer simulations, it has not been seen in detail in experiment. To test the theory on a macroscopic scale, we have devised an RF discharge at low pressure and low density, such that both the mean free path and the Debye length are larger than the feature sizes, as in actual microcircuits. Circular vias of order 1 mm in diam are drilled in an insulating plate exposed to the plasma, and the current and potential at various depths are measured with charge collectors. The potential distribution in each hole is calculated with a Poisson solver, and the ion trajectories are found numerically, giving the expected I - V characteristics of the collector to be compared with measurements. Of particular interest is the variation of the charging currents during the RF cycle.

  9. Color shading technology for design CAD systems

    SciTech Connect

    Mori, K.; Mori, H.; Tanaka, T.; Okuyama, Y.

    1986-01-01

    One issue in new vehicle development that has become increasingly more important is the need to put attractive vehicles on the market at the right time. In recent years vehicle design has become a very crucial factor in this effort. Automakers are required to create vehicles having a higher quality design in a shorter period of time and supply them to the market in a timely fashion. As part of the effort to meet these requirements the automakers have developed a variety of CAD/CAM systems, which counterparts in industry in general. Although most CAD/CAM systems are currently being used primarily at the design and manufacturing stages, the full potential of CAD systems has yet to be realized at the design stage. At Nissan, they have developed a CAD styling system called the Digitized Image Modeling System (DIMS), which serves as a support tool for the creation of new vehicle designs. This system has greatly enhanced the efficiency of the creative activities in the design process and enables them to create vehicles with higher quality designs in a more timely manner. This paper describes how DIMS is being utilized in the design process and focuses in detail on the theory of shading, which occupies a vital position in overall system.

  10. Patterns of shading tolerance determined from experimental ...

    EPA Pesticide Factsheets

    An extensive review of the experimental literature on seagrass shading evaluated the relationship between experimental light reductions, duration of experiment and seagrass response metrics to determine whether there were consistent statistical patterns. There were highly significant linear relationships of both percent biomass and percent shoot density reduction versus percent light reduction (versus controls), although unexplained variation in the data were high. Duration of exposure affected extent of response for both metrics, but was more clearly a factor in biomass response. Both biomass and shoot density showed linear responses to duration of light reduction for treatments 60%. Unexplained variation was again high, and greater for shoot density than biomass. With few exceptions, regressions of both biomass and shoot density on light reduction for individual species and for genera were statistically significant, but also tended to show high degrees of variability in data. Multivariate regressions that included both percent light reduction and duration of reduction as dependent variables increased the percentage of variation explained in almost every case. Analysis of response data by seagrass life history category (Colonizing, Opportunistic, Persistent) did not yield clearly separate response relationships in most cases. Biomass tended to show somewhat less variation in response to light reduction than shoot density, and of the two, may be the prefe

  11. Evaluating the Community Land Model in a pine stand with shading manipulations and 13CO2 labeling

    NASA Astrophysics Data System (ADS)

    Mao, J.; Ricciuto, D. M.; Thornton, P. E.; Warren, J. M.; King, A. W.; Shi, X.; Iversen, C. M.; Norby, R. J.

    2016-02-01

    Carbon allocation and flow through ecosystems regulates land surface-atmosphere CO2 exchange and thus is a key, albeit uncertain, component of mechanistic models. The Partitioning in Trees and Soil (PiTS) experiment-model project tracked carbon allocation through a young Pinus taeda stand following pulse labeling with 13CO2 and two levels of shading. The field component of this project provided process-oriented data that were used to evaluate terrestrial biosphere model simulations of rapid shifts in carbon allocation and hydrological dynamics under varying environmental conditions. Here we tested the performance of the Community Land Model version 4 (CLM4) in capturing short-term carbon and water dynamics in relation to manipulative shading treatments and the timing and magnitude of carbon fluxes through various compartments of the ecosystem. When calibrated with pretreatment observations, CLM4 was capable of closely simulating stand-level biomass, transpiration, leaf-level photosynthesis, and pre-labeling 13C values. Over the 3-week treatment period, CLM4 generally reproduced the impacts of shading on soil moisture changes, relative change in stem carbon, and soil CO2 efflux rate. Transpiration under moderate shading was also simulated well by the model, but even with optimization we were not able to simulate the high levels of transpiration observed in the heavy shading treatment, suggesting that the Ball-Berry conductance model is inadequate for these conditions. The calibrated version of CLM4 gave reasonable estimates of label concentration in phloem and in soil surface CO2 after 3 weeks of shade treatment, but it lacks the mechanisms needed to track the labeling pulse through plant tissues on shorter timescales. We developed a conceptual model for photosynthate transport based on the experimental observations, and we discussed conditions under which the hypothesized mechanisms could have an important influence on model behavior in larger-scale applications

  12. Characterization of shade avoidance responses in Lotus japonicus.

    PubMed

    Ueoka-Nakanishi, Hanayo; Hori, Nanako; Ishida, Kai; Ono, Natsuko; Yamashino, Takafumi; Nakamichi, Norihito; Mizuno, Takeshi

    2011-01-01

    Sessile plants must continuously adjust their growth and development to optimize photosynthetic activity under ever-fluctuating light conditions. Among such light responses in plants, one of the best-characterized events is the so-called shade avoidance, for which a low ratio of the red (R):far-red (FR) light intensities is the most prominent stimulus. Such shade avoidance responses enable plants to overtop their neighbors, thereby enhancing fitness and competitiveness in their natural habitat. Considerable progress has been achieved during the last decade in understanding the molecular mechanisms underlying the shade avoidance responses in the model rosette plant, Arabidopsis thaliana. We characterize here the fundamental aspects of the shade avoidance responses in the model legume, Lotus japonicus, based on the fact that its phyllotaxis (or morphological architecture) is quite different from that of A. thaliana. It was found that L. japonicus displays the characteristic shade avoidance syndrome (SAS) under defined laboratory conditions (a low R:FR ratio, low light intensity, and low blue light intensity) that mimic the natural canopy. In particular, the outgrowth of axillary buds (i.e., both aerial and cotyledonary shoot branching) was severely inhibited in L. japonicus grown in the shade. These results are discussed with special emphasis on the unique aspects of SAS observed with this legume.

  13. Shade Effects on the Dispersal of Airborne Hemileia vastatrix Uredospores.

    PubMed

    Boudrot, Audrey; Pico, Jimmy; Merle, Isabelle; Granados, Eduardo; Vílchez, Sergio; Tixier, Philippe; Filho, Elías de Melo Virginio; Casanoves, Fernando; Tapia, Ana; Allinne, Clémentine; Rice, Robert A; Avelino, Jacques

    2016-06-01

    Hemileia vastatrix caused a severe epidemic in Central America in 2012-13. The gradual development of that epidemic on nearly a continental scale suggests that dispersal at different scales played a significant role. Shade has been proposed as a way of reducing uredospore dispersal. The effect of shade (two strata: Erythrina poeppigiana below and Chloroleucon eurycyclum above) and full sun on H. vastatrix dispersal was studied with Burkard traps in relation to meteorological records. Annual and daily patterns of dispersal were observed, with peaks of uredospore capture obtained during wet seasons and in the early afternoon. A maximum of 464 uredospores in 1 day (in 14.4 m(3) of air) was recorded in October 2014. Interactions between shade/full sun and meteorological conditions were found. Rainfall, possibly intercepted by tree cover and redistributed by raindrops of higher kinetic energy, was the main driver of uredospore dispersal under shade. Wind gusts reversed this effect, probably by inhibiting water accumulation on leaves. Wind gusts also promoted dispersal under dry conditions in full sun, whereas they had no effect under shaded conditions, probably because the canopy blocked the wind. Our results indicate the importance of managing shade cover differentially in rainy versus dry periods to control the dispersal of airborne H. vastatrix uredospores.

  14. Transcriptome response of cassava leaves under natural shade

    PubMed Central

    Ding, Zehong; Zhang, Yang; Xiao, Yi; Liu, Fangfang; Wang, Minghui; Zhu, Xinguang; Liu, Peng; Sun, Qi; Wang, Wenquan; Peng, Ming; Brutnell, Tom; Li, Pinghua

    2016-01-01

    Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and genes related to photosynthesis and carbohydrates metabolism were highly expressed in mature leaves. Compared with the control, shade significantly induced the expression of genes involved in light reaction of photosynthesis, light signaling and DNA synthesis/chromatin structure; however, the genes related to anthocyanins biosynthesis, heat shock, calvin cycle, glycolysis, TCA cycle, mitochondrial electron transport, and starch and sucrose metabolisms were dramatically depressed. Moreover, the shade also influenced the expression of hormone-related genes and transcriptional factors. The findings would improve our understanding of molecular mechanisms of shade response, and shed light on pathways associated with shade-avoidance syndrome for cassava improvement. PMID:27539510

  15. Transcriptome response of cassava leaves under natural shade.

    PubMed

    Ding, Zehong; Zhang, Yang; Xiao, Yi; Liu, Fangfang; Wang, Minghui; Zhu, Xinguang; Liu, Peng; Sun, Qi; Wang, Wenquan; Peng, Ming; Brutnell, Tom; Li, Pinghua

    2016-08-19

    Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and genes related to photosynthesis and carbohydrates metabolism were highly expressed in mature leaves. Compared with the control, shade significantly induced the expression of genes involved in light reaction of photosynthesis, light signaling and DNA synthesis/chromatin structure; however, the genes related to anthocyanins biosynthesis, heat shock, calvin cycle, glycolysis, TCA cycle, mitochondrial electron transport, and starch and sucrose metabolisms were dramatically depressed. Moreover, the shade also influenced the expression of hormone-related genes and transcriptional factors. The findings would improve our understanding of molecular mechanisms of shade response, and shed light on pathways associated with shade-avoidance syndrome for cassava improvement.

  16. Shade improves survival rate of outplanted 2-0 red fir seedlings

    Treesearch

    Donald T. Gordon

    1970-01-01

    Effect of shade on 2-0 red fir seedlings outplanted on the Tahoe National Forest, central California, was studied by comparing five treatments: no shade, low shade for 1 year and for 2 years, and high shade for 1 year and for 2 years. Seedlings benefited from shading-even under apparently excellent survival conditions in the first season. The extra cost of artificial...

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

    PubMed

    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.

  18. New Zealand, SRTM Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    New Zealand straddles the juncture of the Indo-Australian and Pacific tectonic plates, two of Earth's major crustal plates. The two plates generally converge in subduction zones, but in a scissor-like pattern, with the Indo-Austalian plate overriding the Pacific plate to the north and the Pacific plate overriding the Indo-Australian plate to the south. New Zealand is 'what happens' in between at and near the cross point of this scissor pattern. Here the convergence has built two major islands that together exhibit very active volcanoes and fault systems, and these geologic features are very evident in the topographic pattern.

    The North Island lies at the southern end of the west-over-east (Indo-Australian over Pacific) plate convergence. The Pacific plate dives under the North Island and this subduction process leads to melting of rocks at depth, the rise of magma to the surface, and the formation of volcanoes and other geothermal features. Most notable are Mount Taranaki on the west coast, and Mounts Ruapehu, Ngauruhoe, and Tongariro just south of the island's centerpoint, all of which are shown with white peaks in this display. The Rotorua geothermal field occurs further northeast and is evident here as a scattering of comparatively small bumps created by smaller volcanic eruptions.

    The South Island straddles the cross point of the subduction scissor pattern and prominently features a fault system that connects the two subduction zones. (The east-over-west (Pacific over Indo-Australian) plate convergence generally occurs south of the South Island.) The Alpine fault is the major strand of this fault system along most of the length of the island, near and generally paralleling the west coast. Its impact upon the topography is unmistakable, forming an extremely sharp and straight northwest boundary to New Zealand's tallest mountains, the Southern Alps. Although offsets on the Alpine fault are generally right-lateral (35-40 millimeters per year) and

  19. SRTM Colored and Shaded Topography: Haro and Kas Hills, India

    NASA Technical Reports Server (NTRS)

    2001-01-01

    On January 26, 2001, the Kachchh region in western India suffered the most deadly earthquake in India's history. This shaded topography view of landforms northeast of the city of Bhuj depicts geologic structures that are of interest in the study the tectonic processes that may have led to that earthquake. However, preliminary field studies indicate that these structures are composed of Mesozoic rocks that are overlain by younger rocks showing little deformation. Thus these structures may be old, not actively growing, and not directly related to the recent earthquake.

    The Haro Hills are on the left and the Kas Hills are on the right. The Haro Hills are an 'anticline,' which is an upwardly convex elongated fold of layered rocks. In this view, the anticline is distinctly ringed by an erosion resistant layer of sandstone. The east-west orientation of the anticline may relate to the crustal compression that has occurred during India's northward movement toward, and collision with, Asia. In contrast, the largest of the Kas Hills appears to be a tilted (to the south) and faulted (on the north) block of layered rocks. Also seen here, the linear feature trending toward the southwest from the image center is an erosion-resistant 'dike,' which is an igneous intrusion into older 'host' rocks along a fault plane or other crack. These features are simple examples of how shaded topography can provide a direct input to geologic studies.

    In this image, colors show the elevation as measured by the Shuttle Radar Topography Mission (SRTM). Colors range from green at the lowest elevations, through yellow and red, to purple at the highest elevations. Elevations here range from near sea level to about 300 meters (about 1000 feet). Shading has been added, with illumination from the north (image top).

    Elevation data used in this image was acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same

  20. New Zealand, SRTM Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    New Zealand straddles the juncture of the Indo-Australian and Pacific tectonic plates, two of Earth's major crustal plates. The two plates generally converge in subduction zones, but in a scissor-like pattern, with the Indo-Austalian plate overriding the Pacific plate to the north and the Pacific plate overriding the Indo-Australian plate to the south. New Zealand is 'what happens' in between at and near the cross point of this scissor pattern. Here the convergence has built two major islands that together exhibit very active volcanoes and fault systems, and these geologic features are very evident in the topographic pattern.

    The North Island lies at the southern end of the west-over-east (Indo-Australian over Pacific) plate convergence. The Pacific plate dives under the North Island and this subduction process leads to melting of rocks at depth, the rise of magma to the surface, and the formation of volcanoes and other geothermal features. Most notable are Mount Taranaki on the west coast, and Mounts Ruapehu, Ngauruhoe, and Tongariro just south of the island's centerpoint, all of which are shown with white peaks in this display. The Rotorua geothermal field occurs further northeast and is evident here as a scattering of comparatively small bumps created by smaller volcanic eruptions.

    The South Island straddles the cross point of the subduction scissor pattern and prominently features a fault system that connects the two subduction zones. (The east-over-west (Pacific over Indo-Australian) plate convergence generally occurs south of the South Island.) The Alpine fault is the major strand of this fault system along most of the length of the island, near and generally paralleling the west coast. Its impact upon the topography is unmistakable, forming an extremely sharp and straight northwest boundary to New Zealand's tallest mountains, the Southern Alps. Although offsets on the Alpine fault are generally right-lateral (35-40 millimeters per year) and

  1. Direct Volume Rendering with Shading via Three-Dimensional Textures

    NASA Technical Reports Server (NTRS)

    Van Gelder, Allen; Kim, Kwansik

    1996-01-01

    A new and easy-to-implement method for direct volume rendering that uses 3D texture maps for acceleration, and incorporates directional lighting, is described. The implementation, called Voltx, produces high-quality images at nearly interactive speeds on workstations with hardware support for three-dimensional texture maps. Previously reported methods did not incorporate a light model, and did not address issues of multiple texture maps for large volumes. Our research shows that these extensions impact performance by about a factor of ten. Voltx supports orthographic, perspective, and stereo views. This paper describes the theory and implementation of this technique, and compares it to the shear-warp factorization approach. A rectilinear data set is converted into a three-dimensional texture map containing color and opacity information. Quantized normal vectors and a lookup table provide efficiency. A new tesselation of the sphere is described, which serves as the basis for normal-vector quantization. A new gradient-based shading criterion is described, in which the gradient magnitude is interpreted in the context of the field-data value and the material classification parameters, and not in isolation. In the rendering phase, the texture map is applied to a stack of parallel planes, which effectively cut the texture into many slabs. The slabs are composited to form an image.

  2. Direct Volume Rendering with Shading via Three-Dimensional Textures

    NASA Technical Reports Server (NTRS)

    VanGelder, Allen; Kim, Kwansik

    1996-01-01

    A new and easy-to-implement method for direct volume rendering that uses 3D texture maps for acceleration, and incorporates directional lighting, is described. The implementation, called Voltx, produces high-quality images at nearly interactive speeds on workstations with hardware support for three-dimensional texture maps. Previously reported methods did not incorporate a light model, and did not address issues of multiple texture maps for large volumes. Our research shows that these extensions impact performance by about a factor of ten. Voltx supports orthographic, perspective, and stereo views. This paper describes the theory and implementation of this technique, and compares it to the shear-warp factorization approach. A rectilinear data set is converted into a three-dimensional texture map containing color and opacity information. Quantized normal vectors and a lookup table provide efficiency. A new tesselation of the sphere is described, which serves as the basis for normal-vector quantization. A new gradient-based shading criterion is described, in which the gradient magnitude is interpreted in the context of the field-data value and the material classification parameters, and not in isolation. In the rendering phase, the texture map is applied to a stack of parallel planes, which effectively cut the texture into many slabs. The slabs are composited to form an image.

  3. Effect of shading by the table coral Acropora Hyacinthus on understory corals. [Acropora; Pocillopora

    SciTech Connect

    Stimson, J.

    1985-02-01

    Field surveys at Enewetak Atoll, Marshall Islands, show that coral density and diversity is much lower beneath Acropora table corals than in adjacent unshaded areas. Additionally, the understory community is predominantly composed of massive and encrusting species, while branching Acropora and Pocillopora predominate in unshaded areas. Results of experiments in which coral fragments were transferred to the shade of table Acropora and to adjacent unshaded areas show that shading slows the growth and leads to higher mortality of branching species, while massive and encrusting species are unaffected. Light measurements made beneath table Acropora show that illumination and irradiance values fall to levels at which most hermatypic corals do not occur. The fast-growing but fragile table Acropora are abundant in a wide variety of atoll habitats and grow rapidly to form a canopy approx. = 50 cm above the substrate. However, table Acropora also have high mortality rates, so that there is continuous production of unshaded areas. The growth and death of tables thus create local disturbances, and the resulting patchwork of recently shaded and unshaded areas may enhance coral diversity in areas of high coral cover.

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

    PubMed

    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.

  5. Metabolomic tool to identify soybean [Glycine max (L.) Merrill] germplasms with a high level of shade tolerance at the seedling stage

    PubMed Central

    Liu, Jiang; Hu, Baoyu; Liu, Weiguo; Qin, Wenting; Wu, Haijun; Zhang, Jing; Yang, Caiqiong; Deng, Juncai; Shu, Kai; Du, Junbo; Yang, Feng; Yong, Taiwen; Wang, Xiaochun; Yang, Wenyu

    2017-01-01

    The isoflavone profiles of seeds of various soybean genotypes with different levels of shade tolerance at the seedling stage were investigated. High-performance liquid chromatography (HPLC) was used to quantify 12 isoflavones, and the data were analyzed using a multivariate statistical analysis. Combined with field experimental data and an orthogonal partial least-squares discriminant analysis (OPLS-DA), several aglycones (genistein (GE), daidzein (DE), and glycitein (GLE)) were selected and identified as key compounds involved in the shade tolerance of soybean seedlings. Additional correlation analysis and laboratory shading stress experiments with soybean seedlings also confirmed the function of these selected isoflavones, especially GE, in the discrimination of soybean seedlings with different levels of shade tolerance. Furthermore, the structure–antioxidant activity relationships between a range of isoflavones and the plant shade-tolerance mechanism are discussed. Targeted metabolomic analyses of isoflavones could reveal the diversity of shade tolerance in soybean seedlings, thus contributing to the breeding of excellent soybean varieties. PMID:28211897

  6. The acclimation of Tilia cordata stomatal opening in response to light, and stomatal anatomy to vegetational shade and its components.

    PubMed

    Aasamaa, Krõõt; Aphalo, Pedro José

    2017-02-01

    Stomatal anatomical traits and rapid responses to several components of visible light were measured in Tilia cordata Mill. seedlings grown in an open, fully sunlit field (C-set), or under different kinds of shade. The main questions were: (i) stomatal responses to which visible light spectrum regions are modified by growth-environment shade and (ii) which separate component of vegetational shade is most effective in eliciting the acclimation effects of the full vegetational shade. We found that stomatal opening in response to red or green light did not differ between the plants grown in the different environments. Stomatal response to blue light was increased (in comparison with that of C-set) in the leaves grown in full vegetational shade (IABW-set), in attenuated UVAB irradiance (AB-set) or in decreased light intensity (neutral shade) plus attenuated UVAB irradiance (IAB-set). In all sets, the addition of green light-two or four times stronger-into induction light barely changed the rate of the blue-light-stimulated stomatal opening. In the AB-set, stomatal response to blue light equalled the strong IABW-set response. In attenuated UVB-grown leaves, stomatal response fell midway between IABW- and C-set results. Blue light response by neutral shade-grown leaves did not differ from that of the C-set, and the response by the IAB-set did not differ from that of the AB-set. Stomatal size was not modified by growth environments. Stomatal density and index were remarkably decreased only in the IABW- and IAB-sets. It was concluded that differences in white light responses between T. cordata leaves grown in different light environments are caused only by their different blue light response. Differences in stomatal sensitivity are not dependent on altered stomatal anatomy. Attenuated UVAB irradiance is the most efficient component of vegetational shade in stimulating acclimation of stomata, whereas decreased light intensity plays a minor role. © The Author 2016. Published

  7. Shading Contributes to the Reduction of Stem Mechanical Strength by Decreasing Cell Wall Synthesis in Japonica Rice (Oryza sativa L.).

    PubMed

    Wu, Longmei; Zhang, Wujun; Ding, Yanfeng; Zhang, Jianwei; Cambula, Elidio D; Weng, Fei; Liu, Zhenghui; Ding, Chengqiang; Tang, She; Chen, Lin; Wang, Shaohua; Li, Ganghua

    2017-01-01

    Low solar radiation caused by industrial development and solar dimming has become a limitation in crop production in China. It is widely accepted that low solar radiation influences many aspects of plant development, including slender, weak stems and susceptibility to lodging. However, the underlying mechanisms are not well understood. To clarify how low solar radiation affects stem mechanical strength formation and lodging resistance, the japonica rice cultivars Wuyunjing23 (lodging-resistant) and W3668 (lodging-susceptible) were grown under field conditions with normal light (Control) and shading (the incident light was reduced by 60%) with a black nylon net. The yield and yield components, plant morphological characteristics, the stem mechanical strength, cell wall components, culm microstructure, gene expression correlated with cellulose and lignin biosynthesis were measured. The results showed that shading significantly reduced grain yield attributed to reduction of spikelets per panicles and grain weight. The stem-breaking strength decreased significantly under shading treatment; consequently, resulting in higher lodging index in rice plant in both varieties, as revealed by decreased by culm diameter, culm wall thickness and increased plant height, gravity center height. Compared with control, cell wall components including non-structural carbohydrate, sucrose, cellulose, and lignin reduced quite higher. With histochemical straining, shading largely reduced lignin deposition in the sclerenchyma cells and vascular bundle cells compared with control, and decreased cellulose deposition in the parenchyma cells of culm tissue in both Wuyunjing23 and W3668. And under shading condition, gene expression involved in secondary cell wall synthesis, OsPAL, OsCOMT, OsCCoAOMT, OsCCR, and OsCAD2, and primary cell wall synthesis, OsCesA1, OsCesA3, and OsCesA8 were decreased significantly. These results suggest that gene expression involved in the reduction of lignin and

  8. Zagros Mountains, Iran, SRTM Shaded Relief

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The Zagros Mountains in Iran offer a visually stunning topographic display of geologic structure in layered sedimentary rocks. This scene is nearly 100 kilometers (62 miles) wide but is only a small part of similar terrain that covers much of southern Iran. This area is actively undergoing crustal shortening, as global tectonics moves Arabia toward Asia. Consequently, layers of sedimentary rock are folding much like a carpet will fold if pushed. The convex upward folds create structures called anticlines, which are prominently seen here. The convex downward folds (between the anticlines) create structures called synclines, which are mostly buried and hidden by sediments eroding off the anticlines. Layers having differing erosional resistance create distinctive patterns, often sawtooth triangular facets, that encircle the anticlines. Local relief between the higher mountain ridges and their intervening valleys is about 1200 meters (about 4000 feet).

    Salt extrusions and salt 'glaciers' are another set of geologic features readily evident in the topography. Salt deposits, likely created by the evaporation of an ancient inland sea, were buried by the sediments that now make up the layers of the anticlines and synclines. But salt is less dense than most other rocks, so it tends to migrate upward through Earth's crust in vertical columns called 'diapirs'. The compressive folding process has probably facilitated the formation of these diapirs, and the diapirs, in turn, are probably enhancing some anticlines by 'inflating' them with salt. Where the diapirs reach the surface, the salt extrudes, much like lava from a volcano, and the salt flows. Two prominent salt flows are evident in the same valley, leaking from neighboring anticlines, just north of the scene center.

    This shaded relief image was created directly from an SRTM elevation model by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear

  9. Zagros Mountains, Iran, SRTM Shaded Relief Anaglyph

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The Zagros Mountains in Iran offer a visually stunning topographic display of geologic structure in layered sedimentary rocks. This scene is nearly 100 kilometers (62 miles) wide but is only a small part of similar terrain that covers much of southern Iran. This area is actively undergoing crustal shortening, as global tectonics moves Arabia toward Asia. Consequently, layers of sedimentary rock are folding much like a carpet will fold if pushed. The convex upward folds create structures called anticlines, which are prominently seen here. The convex downward folds (between the anticlines) create structures called synclines, which are mostly buried and hidden by sediments eroding off the anticlines. Layers having differing erosional resistance create distinctive patterns, often sawtooth triangular facets, that encircle the anticlines. Local relief between the higher mountain ridges and their intervening valleys is about 1,200 meters (about 4,000 feet).

    Salt extrusions and salt 'glaciers' are another set of geologic features readily evident in the topography. Salt deposits, likely created by the evaporation of an ancient inland sea, were buried by the sediments that now make up the layers of the anticlines and synclines. But salt is less dense than most other rocks, so it tends to migrate upward through Earth's crust in vertical columns called 'diapirs'. The compressive folding process has probably facilitated the formation of these diapirs, and the diapirs, in turn, are probably enhancing some anticlines by 'inflating' them with salt. Where the diapirs reach the surface, the salt extrudes, much like lava from a volcano, and the salt flows. Two prominent salt flows are evident in the same valley, leaking from neighboring anticlines, just north of the scene center.

    This anaglyph was created by deriving a shaded relief image from the SRTM data, draping it back over the SRTM elevation model, and then generating two differing perspectives, one for each eye

  10. Shaded relief, color as height, Fiji

    NASA Technical Reports Server (NTRS)

    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

  11. Southern California Shaded Relief, Color as Height

    NASA Technical Reports Server (NTRS)

    2000-01-01

    From the desert to the mountains to the sea,' this image shows in striking detail the varied topography of Southern California. The data, which cover an area one and a half times the size of New Jersey, were acquired in 15 seconds by the Shuttle Radar Topography Mission (SRTM). The large V-shape across the center of the image is the intersection of the mountains uplifted along two major faults. The San Andreas Fault is the lower part of the 'V' and the Garlock Fault is the upper part. Between the faults is the western Mojave Desert, including the alternate landing site for the Shuttle at Edwards Air Force Base, near the center of the image. The Pacific Coast appears in the lower left of the image, from Oxnard at the left center edge, curving southeast to Los Angeles. The flat blue area along the top is the southern end of California's Central Valley. Along the right edge of the image is NASA's Goldstone Deep Space Tracking Station. Scientists will use data like these to study a broad range of topics, including ecology, the environment, geology, as well as to make assessments of seismic, flood, and wildfire hazards.

    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 3000 meters (10,000 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

  12. Zagros Mountains, Iran, SRTM Shaded Relief

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The Zagros Mountains in Iran offer a visually stunning topographic display of geologic structure in layered sedimentary rocks. This scene is nearly 100 kilometers (62 miles) wide but is only a small part of similar terrain that covers much of southern Iran. This area is actively undergoing crustal shortening, as global tectonics moves Arabia toward Asia. Consequently, layers of sedimentary rock are folding much like a carpet will fold if pushed. The convex upward folds create structures called anticlines, which are prominently seen here. The convex downward folds (between the anticlines) create structures called synclines, which are mostly buried and hidden by sediments eroding off the anticlines. Layers having differing erosional resistance create distinctive patterns, often sawtooth triangular facets, that encircle the anticlines. Local relief between the higher mountain ridges and their intervening valleys is about 1200 meters (about 4000 feet).

    Salt extrusions and salt 'glaciers' are another set of geologic features readily evident in the topography. Salt deposits, likely created by the evaporation of an ancient inland sea, were buried by the sediments that now make up the layers of the anticlines and synclines. But salt is less dense than most other rocks, so it tends to migrate upward through Earth's crust in vertical columns called 'diapirs'. The compressive folding process has probably facilitated the formation of these diapirs, and the diapirs, in turn, are probably enhancing some anticlines by 'inflating' them with salt. Where the diapirs reach the surface, the salt extrudes, much like lava from a volcano, and the salt flows. Two prominent salt flows are evident in the same valley, leaking from neighboring anticlines, just north of the scene center.

    This shaded relief image was created directly from an SRTM elevation model by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear

  13. South America, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2003-01-01

    that indicate the 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

  14. Southern California Shaded Relief, Color as Height

    NASA Technical Reports Server (NTRS)

    2000-01-01

    From the desert to the mountains to the sea,' this image shows in striking detail the varied topography of Southern California. The data, which cover an area one and a half times the size of New Jersey, were acquired in 15 seconds by the Shuttle Radar Topography Mission (SRTM). The large V-shape across the center of the image is the intersection of the mountains uplifted along two major faults. The San Andreas Fault is the lower part of the 'V' and the Garlock Fault is the upper part. Between the faults is the western Mojave Desert, including the alternate landing site for the Shuttle at Edwards Air Force Base, near the center of the image. The Pacific Coast appears in the lower left of the image, from Oxnard at the left center edge, curving southeast to Los Angeles. The flat blue area along the top is the southern end of California's Central Valley. Along the right edge of the image is NASA's Goldstone Deep Space Tracking Station. Scientists will use data like these to study a broad range of topics, including ecology, the environment, geology, as well as to make assessments of seismic, flood, and wildfire hazards.

    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 3000 meters (10,000 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

  15. Shaded relief, color as height, Fiji

    NASA Technical Reports Server (NTRS)

    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

  16. Zagros Mountains, Iran, SRTM Shaded Relief Anaglyph

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The Zagros Mountains in Iran offer a visually stunning topographic display of geologic structure in layered sedimentary rocks. This scene is nearly 100 kilometers (62 miles) wide but is only a small part of similar terrain that covers much of southern Iran. This area is actively undergoing crustal shortening, as global tectonics moves Arabia toward Asia. Consequently, layers of sedimentary rock are folding much like a carpet will fold if pushed. The convex upward folds create structures called anticlines, which are prominently seen here. The convex downward folds (between the anticlines) create structures called synclines, which are mostly buried and hidden by sediments eroding off the anticlines. Layers having differing erosional resistance create distinctive patterns, often sawtooth triangular facets, that encircle the anticlines. Local relief between the higher mountain ridges and their intervening valleys is about 1,200 meters (about 4,000 feet).

    Salt extrusions and salt 'glaciers' are another set of geologic features readily evident in the topography. Salt deposits, likely created by the evaporation of an ancient inland sea, were buried by the sediments that now make up the layers of the anticlines and synclines. But salt is less dense than most other rocks, so it tends to migrate upward through Earth's crust in vertical columns called 'diapirs'. The compressive folding process has probably facilitated the formation of these diapirs, and the diapirs, in turn, are probably enhancing some anticlines by 'inflating' them with salt. Where the diapirs reach the surface, the salt extrudes, much like lava from a volcano, and the salt flows. Two prominent salt flows are evident in the same valley, leaking from neighboring anticlines, just north of the scene center.

    This anaglyph was created by deriving a shaded relief image from the SRTM data, draping it back over the SRTM elevation model, and then generating two differing perspectives, one for each eye

  17. Shaded relief, color as height, Salalah, Oman

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This elevation map shows a part of the southern coast of the Arabian Peninsula including parts of the countries of Oman and Yemen. The narrow coastal plain on the right side of the image includes the city of Salahlah, the second largest city in Oman. Various crops, including coconuts, papayas and bananas, are grown on this plain. The abrupt topography of the coastal mountains wrings moisture from the monsoon, enabling agriculture in the otherwise dry environment of the Arabian Peninsula. These mountains are historically significant as well: Some scholars believe these mountains are the 'southern mountains' of the book of Genesis.

    This image brightness corresponds to shading illumination from the right, while colors show the elevation as measured by the Shuttle Radar Topography Mission. Colors range from green at the lowest elevations to brown at the highest elevations. This image contains about 1400 meters (4600 feet) of total relief. The Arabian Sea is colored blue.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, 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. The 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, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) and the German (DLR) and Italian (ASI)space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

    Size: 149 by 40 kilometers (92 by 25 miles) Location: 16.9 deg. North lat., 53.7 deg. East lon. Orientation: North at top right Date Acquired: February 15, 2000 Image: NASA/JPL/NIMA

  18. Shaded relief, color as height, Salalah, Oman

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This elevation map shows a part of the southern coast of the Arabian Peninsula including parts of the countries of Oman and Yemen. The narrow coastal plain on the right side of the image includes the city of Salahlah, the second largest city in Oman. Various crops, including coconuts, papayas and bananas, are grown on this plain. The abrupt topography of the coastal mountains wrings moisture from the monsoon, enabling agriculture in the otherwise dry environment of the Arabian Peninsula. These mountains are historically significant as well: Some scholars believe these mountains are the 'southern mountains' of the book of Genesis.

    This image brightness corresponds to shading illumination from the right, while colors show the elevation as measured by the Shuttle Radar Topography Mission. Colors range from green at the lowest elevations to brown at the highest elevations. This image contains about 1400 meters (4600 feet) of total relief. The Arabian Sea is colored blue.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, 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. The 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, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) and the German (DLR) and Italian (ASI)space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

    Size: 149 by 40 kilometers (92 by 25 miles) Location: 16.9 deg. North lat., 53.7 deg. East lon. Orientation: North at top right Date Acquired: February 15, 2000 Image: NASA/JPL/NIMA

  19. South America, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2003-01-01

    that indicate the 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

  20. South America, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2003-01-01

    that indicate the 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

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

    NASA Astrophysics Data System (ADS)

    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

  2. Dynamics of the shade-avoidance response in Arabidopsis.

    PubMed

    Ciolfi, Andrea; Sessa, Giovanna; Sassi, Massimiliano; Possenti, Marco; Salvucci, Samanta; Carabelli, Monica; Morelli, Giorgio; Ruberti, Ida

    2013-09-01

    Shade-intolerant plants perceive the reduction in the ratio of red light (R) to far-red light (FR) as a warning of competition with neighboring vegetation and display a suite of developmental responses known as shade avoidance. In recent years, major progress has been made in understanding the molecular mechanisms underlying shade avoidance. Despite this, little is known about the dynamics of this response and the cascade of molecular events leading to plant adaptation to a low-R/FR environment. By combining genome-wide expression profiling and computational analyses, we show highly significant overlap between shade avoidance and deetiolation transcript profiles in Arabidopsis (Arabidopsis thaliana). The direction of the response was dissimilar at the early stages of shade avoidance and congruent at the late ones. This latter regulation requires LONG HYPOCOTYL IN FAR RED1/SLENDER IN CANOPY SHADE1 and phytochrome A, which function largely independently to negatively control shade avoidance. Gene network analysis highlights a subnetwork containing ELONGATED HYPOCOTYL5 (HY5), a master regulator of deetiolation, in the wild type and not in phytochrome A mutant upon prolonged low R/FR. Network analysis also highlights a direct connection between HY5 and HY5 HOMOLOG (HYH), a gene functionally implicated in the inhibition of hypocotyl elongation and known to be a direct target of the HY5 transcription factor. Kinetics analysis show that the HYH gene is indeed late induced by low R/FR and that its up-regulation depends on the action of HY5, since it does not occur in hy5 mutant. Therefore, we propose that one way plants adapt to a low-R/FR environment is by enhancing HY5 function.

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

    PubMed

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

    2012-09-01

    To compare microhardness along the root canal post space of two resin cements in different shades and a dual-cure resin core material. Root canals of 21 bovine incisors were prepared for post space. Translucent posts (X∘Post, Dentsply DeTrey) were luted using one the following resin luting agent: Calibra (Dentsply DeTrey) in Translucent, Medium and Opaque shades, RelyX Unicem (3M ESPE) in Translucent, A2 and A3 shades and the dual-cure resin core material Core∘X flow. All materials were applied according to manufacturers' instructions and were all photopolymerized (Bluephase LED unit, Ivoclar Vivadent, 40s). After 24 hours, roots were transversally cut into 9 slices 1 mm thick from the coronal to apical extremes, three corresponding to each root third. Then, VHNs were recorded (100gf, 30 s) on the resin luting materials along the adhesive interface in all sections. Data were analyzed by two-way ANOVA and SNK tests (α=0.05). A significant influence on microhardness of resin luting material in their respective shades (p<0.0001), root third (p<0.0001) and interactions between them was detected (p<0.0001). RelyX Unicem cement showed the highest microhardness values and Calibra the lowest, regardless of the shade selected. All resin luting materials tested exhibited a significantly higher microhardness in the cervical third. Microhardness of resin luting agents tested inside the canal is dependent on material brand and resin cement shade seems to be a less relevant factor. Microhardness decreased along the root canal, regardless of the shade selected.

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

    SciTech Connect

    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.

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

    SciTech Connect

    MacAlpine, Sara; Deline, Chris

    2015-06-14

    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.

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

    PubMed

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

    2014-01-01

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

  7. Shading as a Control Method for Invasive European Frogbit (Hydrocharis morsus-ranae L.)

    PubMed Central

    Zhu, Bin; Ellis, Michael S.; Fancher, Kelly L.; Rudstam, Lars G.

    2014-01-01

    Invasive European frogbit (Hydrocharis morsus-ranae L.) has negative environmental and economic impacts in North American water bodies. It is therefore important to develop effective management tools to control this invasive species. This study investigated shading as a control method for European frogbit in both greenhouse and lake mesocosm experiments. A series of shade treatments (0%, 50%, 60%, 70%, 80%, and 100%) were tested in the greenhouse for three weeks. Results showed that the 100% shade was most effective at controlling European frogbit, and other shade treatments greater than 50% were less effective, reducing frogbit biomass up to 38.2%. There were no differences found in temperature between treatments, but dissolved oxygen decreased as shading increased. A lake mesocosm experiment utilizing 0% shade, 70% shade, and 100% shade treatments was performed in a sheltered inlet of Oneida Lake in New York State for over one month. Resulting European frogbit biomass was significantly (25 times) less in areas treated with the 70% shade and nearly zero with the 100% shade. Shading did not affect temperature but improved DO conditions. Results on the shading effects on submerged macrophytes were not conclusive: no significant differences in changes in species richness and abundance between the three groups at the end of studied period suggested no shading effects; significant differences between the beginning and end communities in the 70% shade and the 100% shade but not in the control group indicated significant impacts of shading. This study is the first one to investigate shading as a control method for European frogbit and it is concluded that a moderately high density shade can effective remove European frogbit likely with minor impacts on the environment. More experiments with larger scales and longer time periods are recommended for further investigation. PMID:24886916

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

    NASA Astrophysics Data System (ADS)

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

    2009-08-01

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

  9. Plant Responses to Vegetation Proximity: A Whole Life Avoiding Shade.

    PubMed

    Roig-Villanova, Irma; Martínez-García, Jaime F

    2016-01-01

    In high density of vegetation, plants detect neighbors by perceiving changes in light quality through phytochrome photoreceptors. Close vegetation proximity might result in competition for resources, such as light. To face this challenge, plants have evolved two alternative strategies: to either tolerate or avoid shade. Shade-avoiding species generally adapt their development by inducing hypocotyl, stem, and petiole elongation, apical dominance and flowering, and decreasing leaf expansion and yield, a set of responses collectively known as the shade avoidance syndrome (SAS). The SAS responses have been mostly studied at the seedling stage, centered on the increase of hypocotyl elongation. After compiling the main findings about SAS responses in seedlings, this review is focused on the response to shade at adult stages of development, such as petioles of adult leaves, and the little information available on the SAS responses in reproductive tissues. We discuss these responses based on the knowledge about the molecular mechanisms and components with a role in regulating the SAS response of the hypocotyls of Arabidopsis thaliana. The transcriptional networks involved in this process, as well as the communication among the tissues that perceive the shade and the ones that respond to this stimulus will also be briefly commented.

  10. Plant Responses to Vegetation Proximity: A Whole Life Avoiding Shade

    PubMed Central

    Roig-Villanova, Irma; Martínez-García, Jaime F.

    2016-01-01

    In high density of vegetation, plants detect neighbors by perceiving changes in light quality through phytochrome photoreceptors. Close vegetation proximity might result in competition for resources, such as light. To face this challenge, plants have evolved two alternative strategies: to either tolerate or avoid shade. Shade-avoiding species generally adapt their development by inducing hypocotyl, stem, and petiole elongation, apical dominance and flowering, and decreasing leaf expansion and yield, a set of responses collectively known as the shade avoidance syndrome (SAS). The SAS responses have been mostly studied at the seedling stage, centered on the increase of hypocotyl elongation. After compiling the main findings about SAS responses in seedlings, this review is focused on the response to shade at adult stages of development, such as petioles of adult leaves, and the little information available on the SAS responses in reproductive tissues. We discuss these responses based on the knowledge about the molecular mechanisms and components with a role in regulating the SAS response of the hypocotyls of Arabidopsis thaliana. The transcriptional networks involved in this process, as well as the communication among the tissues that perceive the shade and the ones that respond to this stimulus will also be briefly commented. PMID:26973679

  11. Shade Guide for the Fabrication of Acrylic Denture Based on Mucosal Colour

    PubMed Central

    Da Costa, Godwin Clovis; Aras, Meena Ajay

    2017-01-01

    This article highlights the use of a simple and convenient shade guide system which not only helps in choosing the shade tab that matches with the colour of the mucosa, but, also helps in the fabrication of the precise shade of acrylic resin for making the denture. The shade guide is fabricated by mixing specified quantities of various colours of acrylic polymer in order to obtain various shade tabs. The method for fabrication of the shade guide and the clinical procedure has been discussed. PMID:28384988

  12. Analysis and conceptual design of a lunar radiator parabolic shade

    NASA Technical Reports Server (NTRS)

    Ewert, Michael K.; Clark, Craig S.

    1991-01-01

    On the moon, the available heat sink temperature for a vertical unshaded radiator at the equator is 322 K. A method of reducing this heat sink temperature using a parabolic trough shading device was investigated. A steady state heat balance was performed to predict the available heat sink temperature. The effect of optical surface properties on system performance was investigated. Various geometric configurations were also evaluated. A flexible shade conceptual design is presented which greatly reduces the weight and stowed volume of the system. The concept makes use of the natural catenary shape assumed by a flexible material when supported at two points. The catenary shape is very near parabolic. The lunar radiator parabolic shade design presented integrates the energy collection and rejection of a solar dynamic power cycle with the moderate temperature waste heat rejection of a lunar habitat.

  13. Analysis and conceptual design of a lunar radiator parabolic shade

    NASA Astrophysics Data System (ADS)

    Ewert, Michael K.; Clark, Craig S.

    On the moon, the available heat sink temperature for a vertical unshaded radiator at the equator is 322 K. A method of reducing this heat sink temperature using a parabolic trough shading device was investigated. A steady state heat balance was performed to predict the available heat sink temperature. The effect of optical surface properties on system performance was investigated. Various geometric configurations were also evaluated. A flexible shade conceptual design is presented which greatly reduces the weight and stowed volume of the system. The concept makes use of the natural catenary shape assumed by a flexible material when supported at two points. The catenary shape is very near parabolic. The lunar radiator parabolic shade design presented integrates the energy collection and rejection of a solar dynamic power cycle with the moderate temperature waste heat rejection of a lunar habitat.

  14. Shade, water and mass: Passive cooling in Andalucia

    SciTech Connect

    Carrasco, V.; Reynolds, J.S.

    1996-10-01

    A thermally massive, ancient patio (courtyard) house in Bornos Spain was monitored for 25 days in summer 1995. Data for light, relative humidity and air temperature were recorded at the floor`s center in the 3-story deep patio. Temperatures were also recorded in one ground floor and one second floor room adjacent to the patio, and on the roof terrace. Victor Carrasco (the owner) kept a daily record of his actions of shading (with a toldo), of watering the patio`s absorbent floor, and of opening windows for night ventilation. The data show the effects of shading, watering and night ventilation. The cycles of temperature and relative humidity in the center of the patio floor reveal a pattern of thermal sailing where skillful manipulations of shading, evaporative cooling, radiation and night ventilation result in indoor comfort despite the highest outside temperatures of this century that occurred in late July 1995.

  15. Objective measurement of shade color in age estimation

    PubMed Central

    Vaidya, Sharad; Ahuja, Nitin; Bajaj, Puneet; Kapoor, Charu; Sabarwal, Robin; Rajpal, Karan

    2015-01-01

    Introduction: Age estimation is an important subspecialty of forensic medicine. Dental hard tissues are highly resistant to degradation and putrefaction. Enamel is translucent and varies in color from light yellow to grey white. The color of the teeth has been reported to be affected by chronological age. Enamel color may also depend on environmental factors viz. diet, occupational habits, vitamin deficiencies, fluoride level in drinking water etc., It has been found that color changes in dentin vary from white to yellow. Studies have been done to measure the dentin color for age estimation. Aim: To find a correlation between the enamel color and chronological age and secondly to estimate the age of an individual from enamel color. Material and Methods: A total of 300 patients visiting the outpatient department of oral medicine and radiology were selected. Out of those, 150 were men and 150 women. The patients were divided into V groups based on the age. A thorough case history was taken for all the patients. Maxillary Central and Lateral incisor was used for the estimation of shade. The enamel color was evaluated using a VITA classical shade guide. Statistical Analysis: Data were exported to an Excel spread sheet and statistical analysis was performed using the SPSS. Linear regression analysis was used to find correlations between age and enamel shade. Results: In the group 1 and 2 i.e. from 15 to 36 years, the shades A 2 and B 2 (reddish hue) was found to be most common. While in the group 3 and 4, shades ranged from A 3 to B 3 (brownish to yellowish hue). In the patients above 59 years i.e. group 5 the enamel shade with greyish hue was found to be most common. Conclusion: Age determination using enamel color can be tried in forensic cases in the identification of individuals with no birth records. PMID:26816455

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

    PubMed

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

    2016-01-01

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

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

    PubMed

    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.

  18. Sucrose feeding reverses shade-induced kernel losses in maize.

    PubMed

    Hiyane, Rie; Hiyane, Shinichi; Tang, An Ching; Boyer, John S

    2010-09-01

    Water limitations can inhibit photosynthesis and change gene expression in ways that diminish or prevent reproductive development in plants. Sucrose fed to the plants can reverse the effects. To test whether the reversal acts generally by replacing the losses from photosynthesis, sucrose was fed to the stems of shaded maize plants (Zea mays) during reproductive development. Shading was adjusted to mimic the inhibition of photosynthesis around the time of pollination in water-limited plants. Glucose and starch were imaged and quantified in the female florets. Sucrose was infused into the stems to vary the sugar flux to the ovaries. Ovaries normally grew rapidly and contained large amounts of glucose and starch, with a glucose gradient favouring glucose movement into the developing ovary. Shade inhibited photosynthesis and diminished ovary and kernel size, weight, and glucose and starch contents compared with controls. The glucose gradient became small. Sucrose fed to the stem reversed these losses, and kernels were as large as the controls. Despite similar inhibition of photosynthesis, the depletion of ovary glucose and starch was not as severe in shade as during a comparable water deficit. Ovary abortion prevalent during water deficits did not occur in the shade. It is suggested that this difference may have been caused by more translocation in shade than during the water deficit, which prevented low sugar contents necessary to trigger an up-regulation of senescence genes known to be involved in abortion. Nevertheless, sucrose feeding reversed kernel size losses and it is concluded that feeding acted generally to replace diminished photosynthetic activity.

  19. Sucrose feeding reverses shade-induced kernel losses in maize

    PubMed Central

    Hiyane, Rie; Hiyane, Shinichi; Tang, An Ching; Boyer, John S.

    2010-01-01

    Background and Aims Water limitations can inhibit photosynthesis and change gene expression in ways that diminish or prevent reproductive development in plants. Sucrose fed to the plants can reverse the effects. To test whether the reversal acts generally by replacing the losses from photosynthesis, sucrose was fed to the stems of shaded maize plants (Zea mays) during reproductive development. Methods Shading was adjusted to mimic the inhibition of photosynthesis around the time of pollination in water-limited plants. Glucose and starch were imaged and quantified in the female florets. Sucrose was infused into the stems to vary the sugar flux to the ovaries. Key Results Ovaries normally grew rapidly and contained large amounts of glucose and starch, with a glucose gradient favouring glucose movement into the developing ovary. Shade inhibited photosynthesis and diminished ovary and kernel size, weight, and glucose and starch contents compared with controls. The glucose gradient became small. Sucrose fed to the stem reversed these losses, and kernels were as large as the controls. Conclusions Despite similar inhibition of photosynthesis, the depletion of ovary glucose and starch was not as severe in shade as during a comparable water deficit. Ovary abortion prevalent during water deficits did not occur in the shade. It is suggested that this difference may have been caused by more translocation in shade than during the water deficit, which prevented low sugar contents necessary to trigger an up-regulation of senescence genes known to be involved in abortion. Nevertheless, sucrose feeding reversed kernel size losses and it is concluded that feeding acted generally to replace diminished photosynthetic activity. PMID:20616114

  20. Iterative CT shading correction with no prior information

    NASA Astrophysics Data System (ADS)

    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

  1. Seamstresses Stitch a Sun-Shade for Skylab

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Two seamstresses stitch together a sun-shade for the Skylab Orbital Workshop, the first United States Experimental space station in orbit, which lost its thermal protection shield during the launch on May 14, 1973. Without the heat shield, the temperature inside the Orbital Workshop became dangerously high, rendering the workshop uninhabitable and threatening the interior insulation and adhesive to deteriorate. Marshall engineers and scientists worked tirelessly around the clock to develop an emergency repair procedure. The Skylab crew and the repair kits were launched just 11 days after the incident. The crew successfully deployed the twin-pole sail parasol sun-shade during their EVA (Extravehicular Activity) the next day.

  2. Iterative CT shading correction with no prior information.

    PubMed

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

    2015-11-07

    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

  3. Slow induction of photosynthesis on shade to sun transitions in wheat may cost at least 21% of productivity.

    PubMed

    Taylor, Samuel H; Long, Stephen P

    2017-09-26

    Wheat is the second most important direct source of food calories in the world. After considerable improvement during the Green Revolution, increase in genetic yield potential appears to have stalled. Improvement of photosynthetic efficiency now appears a major opportunity in addressing the sustainable yield increases needed to meet future food demand. Effort, however, has focused on increasing efficiency under steady-state conditions. In the field, the light environment at the level of individual leaves is constantly changing. The speed of adjustment of photosynthetic efficiency can have a profound effect on crop carbon gain and yield. Flag leaves of wheat are the major photosynthetic organs supplying the grain of wheat, and will be intermittently shaded throughout a typical day. Here, the speed of adjustment to a shade to sun transition in these leaves was analysed. On transfer to sun conditions, the leaf required about 15 min to regain maximum photosynthetic efficiency. In vivo analysis based on the responses of leaf CO2 assimilation (A) to intercellular CO2 concentration (ci) implied that the major limitation throughout this induction was activation of the primary carboxylase of C3 photosynthesis, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). This was followed in importance by stomata, which accounted for about 20% of the limitation. Except during the first few seconds, photosynthetic electron transport and regeneration of the CO2 acceptor molecule, ribulose-1,5-bisphosphate (RubP), did not affect the speed of induction. The measured kinetics of Rubisco activation in the sun and de-activation in the shade were predicted from the measurements. These were combined with a canopy ray tracing model that predicted intermittent shading of flag leaves over the course of a June day. This indicated that the slow adjustment in shade to sun transitions could cost 21% of potential assimilation.This article is part of the themed issue 'Enhancing photosynthesis

  4. Evaluation of color changes in the Vitapan Classical Shade Guide after disinfection.

    PubMed

    Alshethri, S E

    2014-01-01

    The purpose of this study was to evaluate how one, two, and three years of simulated treatments affect the colors of Vitapan Classical Shade Guide tabs after being chemically disinfected. Ten shade tabs (one, control; nine, disinfection) were evaluated visually and by chromameter for color changes after disinfection. Results showed that 0.62 ΔE was found after three years of disinfection. The color changes in the shade guide tabs were perceptible or noticeable to the human eye in eight out of 45 shade tabs (17.8%) after two years and in 13 out of 45 shade tabs (28.9%) after three years of treatment. It was concluded that one shade guide should be retained as a control and periodically compared with the shade guide in use to determine when the shade tabs in use should be replaced or discarded.

  5. Assessment of color fidelity of several composite resins compared to their Vita Classical shade registration.

    PubMed

    Barcellos, Daphne Camara; Torres, Carlos Rocha Gomes; Pucci, Cesar Rogerio; Borges, Alessandra Buhler; Goncalves, Sergio Eduardo de Paiva; Limeira, Renata; Souza, Dayane

    2010-01-01

    This study compared the color fidelity of different composite resins with their registration in the Vita Classical Shade Guide. Using a prefabricated Teflon mold, 120 specimens were divided into four groups (n = 30), according to the resin tested. Three subgroups (n = 10) were prepared for each resin group; these subgroups tested enamel shade, dentin shade, and enamel and dentin shade. Three measurements were performed to verify whether the tooth shade matched that of the Vita Classical Shade Guide. The color was evaluated and the shade variations were calculated. The data were submitted to a three-way ANOVA test (time, color match, and composite type), followed by Tukey's test. It was concluded that all composite resins showed color differences in relation to the Vita Classical Shade Guide.

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

    PubMed Central

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

    2015-01-01

    Purpose of the Study: The purpose was to investigate the differences in tooth shade value according to age, gender and skin color among a sample of the local population in Bengaluru, India. Methodology: The study comprised 100 subjects belonging to both gender between the age groups of 16 years to 55 years. Tooth shade values of permanent maxillary left or right central incisors were recorded using the Vitapan 3D-Master shade guide. Skin color was matched using the Radiance compact makeup shades as a guide. Results: Chi-square statistical test demonstrated that younger subjects have lighter tooth shade values. No statistically significant differences were recorded in tooth shade value according to gender or skin color. Conclusion: Within the limitations of the current study, it can be concluded that tooth shade value is significantly influenced by age. Gender and skin color appear not to have a significant relation to tooth shade value. PMID:26929500

  7. 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.

    PubMed

    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.

  8. 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.

    PubMed

    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.

  9. Shade images of forested areas obtained from LANDSAT MSS data

    NASA Technical Reports Server (NTRS)

    Shimabukuro, Yosio Edemir; Smith, James A.

    1989-01-01

    The pixel size in the present day Remote Sensing systems is large enough to include different types of land cover. Depending upon the target area, several components may be present within the pixel. In forested areas, generally, three main components are present: tree canopy, soil (understory), and shadow. The objective is to generate a shade (shadow) image of forested areas from multispectral measurements of LANDSAT MSS (Multispectral Scanner) data by implementing a linear mixing model, where shadow is considered as one of the primary components in a pixel. The shade images are related to the observed variation in forest structure, i.e., the proportion of inferred shadow in a pixel is related to different forest ages, forest types, and tree crown cover. The Constrained Least Squares (CLS) method is used to generate shade images for forest of eucalyptus and vegetation of cerrado using LANDSAT MSS imagery over Itapeva study area in Brazil. The resulted shade images may explain the difference on ages for forest of eucalyptus and the difference on three crown cover for vegetation of cerrado.

  10. Reproductive efficiency and shade avoidance plasticity under simulated competition.

    PubMed

    Fazlioglu, Fatih; Al-Namazi, Ali; Bonser, Stephen P

    2016-07-01

    Plant strategy and life-history theories make different predictions about reproductive efficiency under competition. While strategy theory suggests under intense competition iteroparous perennial plants delay reproduction and semelparous annuals reproduce quickly, life-history theory predicts both annual and perennial plants increase resource allocation to reproduction under intense competition. We tested (1) how simulated competition influences reproductive efficiency and competitive ability (CA) of different plant life histories and growth forms; (2) whether life history or growth form is associated with CA; (3) whether shade avoidance plasticity is connected to reproductive efficiency under simulated competition. We examined plastic responses of 11 herbaceous species representing different life histories and growth forms to simulated competition (spectral shade). We found that both annual and perennial plants invested more to reproduction under simulated competition in accordance with life-history theory predictions. There was no significant difference between competitive abilities of different life histories, but across growth forms, erect species expressed greater CA (in terms of leaf number) than other growth forms. We also found that shade avoidance plasticity can increase the reproductive efficiency by capitalizing on the early life resource acquisition and conversion of these resources into reproduction. Therefore, we suggest that a reassessment of the interpretation of shade avoidance plasticity is necessary by revealing its role in reproduction, not only in competition of plants.

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

    Treesearch

    Naijiang Wang; Yong Wang; Callie J. Schweitzer

    2011-01-01

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

  12. Reliability of shade selection using an intraoral spectrophotometer.

    PubMed

    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.

  13. Winter shading of blueberry plants in the southeastern United States

    USDA-ARS?s Scientific Manuscript database

    In Central Florida, southern highbush blueberries are treated with hydrogen cyanamide to replace lack of chilling and enhance flowering and fruiting. Experiments were conducted to determine the effects of repeated applications of processed kaolin particle and flat-top shade structure on blueberry p...

  14. VIEW OF EAST SIDE OF CEDAR DRIVE, SHOWING SHADED CANOPY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF EAST SIDE OF CEDAR DRIVE, SHOWING SHADED CANOPY FORMED BY MONKEYPOD TREES. VIEW FACING EAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  15. VIEW OF SHADED REAR YARD WITH CHAINLINK FENCE AND TERRACING, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF SHADED REAR YARD WITH CHAINLINK FENCE AND TERRACING, BEHIND 559 BIRCH CIRCLE. VIEW FACING EAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  16. VIEW OF SHADED REAR YARDS AND TERRACING, SHOWING REAR OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF SHADED REAR YARDS AND TERRACING, SHOWING REAR OF 527 BIRCH CIRCLE ON LEFT. VIEW FACING NORTHEAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  17. Evaluating shading bias in malaise and intercept traps

    USGS Publications Warehouse

    Irvine, Kathryn M.; Woods, Stephen A.

    2007-01-01

    Foresters are increasingly focusing on landscape level management regimes. At the landscape level, managed acreage may differ substantially in structure and micro-climatic conditions. Trapping is a commonly used method to evaluate changes in insect communities across landscapes. Among those trapping techniques, Malaise and window-pane traps are conveniently deployed to collect large numbers of insects for relative estimates of density. However, the catch within traps may be affected by a wide range of environmental variables including trap location, height, and factors such as exposure to sunlight and temperature. Seven experiments were conducted from 1996 through 2000 to evaluate the effects of shading on trap catch of a variety of Malaise trap designs and one window-pane trap design. Overall, differences in shading effects on trap catch were detected across different traps and taxa and suggested that, in general, more insects are collected in traps that were in direct sunlight. The effect of shading varied from a reduction in trap catch of 10 % to an increase of 7%, the results depended on trap color. Diptera, Coleoptera, and Homoptera were most likely to exhibit this bias. In contrast, trap catch of the Hymenoptera was the most variable and appeared to be sensitive to factors that might interact with sun/shade conditions

  18. Shade avoidance and the regulation of leaf inclination in Arabidopsis.

    PubMed

    Mullen, Jack L; Weinig, Cynthia; Hangarter, Roger P

    2006-06-01

    As a rosette plant, Arabidopsis thaliana forms leaves near to the ground, which causes the plant to be vulnerable to shading by neighbours. One mechanism to avoid such shading is the regulation of leaf inclination, such that leaves can be raised to more vertical orientations to prevent neighbouring leaves from overtopping them. Throughout Arabidopsis rosette development, rosette leaves move to more vertical orientations when shaded by neighbouring leaves, exposed to low light levels or placed in the dark. After dark-induced reorientation of leaves, returning them to white light causes the leaves to reorient to more horizontal inclinations. These light-dependent leaf movements are more robust than, and distinct from, the diurnal movements of rosette leaves. However, the movements are gated by the circadian clock. The light-dependent leaf orientation response is mediated primarily through phytochromes A, B and E, with the orientation varying with the ratio of red light to far-red light, consistent with other shade-avoidance responses. However, even plants lacking these phytochromes were able to alter leaf inclination in response to white light, suggesting a role for other photoreceptors. In particular, we found significant changes in leaf inclination for plants exposed to green light. This green light response may be caused, in part, by light-dependent regulation of abscisic acid (ABA) biosynthesis.

  19. The use of shaded fuelbreaks in landscape fire management

    Treesearch

    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...

  20. Body temperature and behavioral activities of four breeds of heifers in shade and full sun

    USDA-ARS?s Scientific Manuscript database

    Heifers from four breeds, eight of each breed, were housed in two types of feedlot pens – one with shade and the other with no shade (exposed to full sun). The breeds were: Black Angus, Charolais (white), MARC I (tan) and MARC III (dark red). The objectives were to determine whether shade made a ...

  1. Proximity signal and shade avoidance differences between early and late successional trees.

    PubMed

    Gilbert, I R; Jarvis, P G; Smith, H

    2001-06-14

    Competitive interactions between plants determine the success of individuals and species. In developing forests, competition for light is the predominant factor. Shade tolerators acclimate photosynthetically to low light and are capable of long-term survival under the shade cast by others, whereas shade avoiders rapidly dominate gaps but are overtaken in due course by shade-tolerant, later successional species. Shade avoidance results from the phytochrome-mediated perception of far-red radiation (700-800 nm) scattered from the leaves of neighbours, provides early warning of shading, and induces developmental responses that, when successful, result in the overgrowth of those neighbours. Shade tolerators cast a deep shade, whereas less-tolerant species cast light shade, and saplings tend to have high survivorship in shade cast by conspecific adults, but high rates of mortality when shaded by more-tolerant species. Here we report a parallel relationship in which the shade-avoidance responses of three tree species are inversely proportional to proximity signals generated by those species. On this basis, early successional species generate small proximity signals but react strongly to them, whereas late successional species react weakly but generate strong signals.

  2. 29 CFR 780.506 - Dependence of exemption on shade-grown tobacco operations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Dependence of exemption on shade-grown tobacco operations... FAIR LABOR STANDARDS ACT Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco §...

  3. 29 CFR 780.505 - Definition of “shade-grown tobacco.”

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Definition of âshade-grown tobacco.â 780.505 Section 780... Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco § 780.505 Definition of...

  4. 29 CFR 780.505 - Definition of “shade-grown tobacco.”

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Definition of âshade-grown tobacco.â 780.505 Section 780... Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco § 780.505 Definition of...

  5. 29 CFR 780.505 - Definition of “shade-grown tobacco.”

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Definition of âshade-grown tobacco.â 780.505 Section 780... Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco § 780.505 Definition of...

  6. 29 CFR 780.506 - Dependence of exemption on shade-grown tobacco operations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Dependence of exemption on shade-grown tobacco operations... FAIR LABOR STANDARDS ACT Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco §...

  7. 29 CFR 780.506 - Dependence of exemption on shade-grown tobacco operations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Dependence of exemption on shade-grown tobacco operations... FAIR LABOR STANDARDS ACT Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco §...

  8. 29 CFR 780.506 - Dependence of exemption on shade-grown tobacco operations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Dependence of exemption on shade-grown tobacco operations... FAIR LABOR STANDARDS ACT Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco §...

  9. 29 CFR 780.505 - Definition of “shade-grown tobacco.”

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Definition of âshade-grown tobacco.â 780.505 Section 780... Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco § 780.505 Definition of...

  10. Stream shading, summer streamflow and maximum water temperature following intense wildfire in headwater streams

    Treesearch

    Michael Amaranthus; Howard Jubas; David Arthur

    1989-01-01

    Adjacent headwater streams were monitored for postfire shade, summer streamflow and maximum water temperature following the 40,000 ha Silver Complex fire in southern Oregon. Average postfire shade (30 percent) for the three streams was considerably less than prefire shade (est.>90 percent). Dramatic increases in direct solar radiation resulted in large but variable...

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

    USDA-ARS?s Scientific Manuscript database

    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 ...

  12. Effect of shade on summer body temperature and respiration rate of Angus, Brahman, and Romosinuano heifers

    USDA-ARS?s Scientific Manuscript database

    To determine the effect of shade during summer in Florida on rectal temperature and respiration rate, a total of 24 heifers (8 Angus, 8 Brahman, and 8 Romosinuano) were utilized. Heifers were allotted by breed to one of two treatment groups, shade or no shade. Heifers were acclimated to treatments f...

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

    Treesearch

    Jean Lienard; Ionut Florescu; Nikolay. Strigul

    2015-01-01

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

  14. Shading reduces growth of longleaf and loblolly pine seedlings in containers

    Treesearch

    James P. Barnett

    1989-01-01

    Development of longleaf (Pinus palustris Mill.) and loblolly (P. taeda L.) pine seediings growing under three light conditions--full sunlight, 30% shade, and 50% shade--was evaluated. Although there was little difference between development of seedlings in 30% and 50% shade, those grown is full sunlight were signiticantly larger...

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

    Treesearch

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

    2007-01-01

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

  16. Performance of Dental Students in Shade Matching: Impact of Training.

    PubMed

    Samra, Adriana P Buhrer; Moro, Marcella G; Mazur, Rui F; Vieira, Sergio; De Souza, Evelise M; Freire, Andrea; Rached, Rodrigo N

    2017-04-01

    The present study evaluated the effect of training on dental students' ability for matching two different shade guides. The study was conducted in 2012. The participants were 88 male and female undergraduate dental students from Brazil and Portugal, with or without previous color education and vision refractive errors (response rate of 73.33%). They were asked to match a pair set of the shade guides Vita Classical (VC) and Vitapan 3D Master (3DM), with a 20-minutes' rest between each match. The sets were assembled over a neutral gray background and under controlled light. About 7-10 days later, all participants watched a video lecture on color education and repeated the matching procedure. The percentage of matches was calculated and submitted to statistical analysis for the variables gender, geographic region, shade guide and previous color education (Mann-Whitney tests), vision refractive errors (Kruskal-Wallis), and training (Wilcoxon signed rank). All tests were performed at a confidence level of 95%. Training increased the percentage of matches for all groups, except for Portuguese and hyperopic individuals (VC and 3DM) and men (3DM). Previous color education affected VC shade matching before training. Gender, refractive errors, and geographic region did not affect shade matching ability. Previous education and training in color positively affected shade-matching ability of dental students on shade guide pairing tests. The subjectivity of the visual method might not be a clinical concern in daily practice. The human eye can detect small differences in color and visualize the tooth with all its complex geometry, multilayered tissues, and secondary color parameters. Therefore, any color-matching task will be judged by the patient and/or other observers with consideration to this complexity. In other words, visual assessment is paramount to the success/failure of esthetic restorative procedures. The efficiency of the visual color method may be improved by color

  17. Shading responses of carbon allocation dynamics in mountain grassland

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

  18. Energy Balance Alterations Due to Cropland Conversion in a Tropical Montane Environment: Shaded Coffee to Sugarcane

    NASA Astrophysics Data System (ADS)

    Alvarado-Barrientos, M. S.; Holwerda, F.; Salazar-Martinez, D.

    2014-12-01

    Although land use change (LUC) is an important driver of changes in climate, very limited field observations of atmosphere-landscape interactions exist in tropical montane zones to examine the extent to which LUCs affect climate locally and regionally. The lack of ground observations hampers the evaluation of satellite-derived datasets of land surface parameters as well as the validation of regional climate models. The first results of an ongoing study of the climate effects of a LUC trajectory in the lower montane region (1200 m a.s.l.) of central Veracruz, Mexico, are presented. The radiation balance, turbulent fluxes and soil heat flux were measured in order to obtain field-derived land surface parameters (albedo and Bowen ratio) of two contrasting land uses: shaded coffee (CO) and sugarcane (SU) plantations. Measurements were conducted on days representing different seasons and crop stages during 2014: cold-dry (January), warm-dry (March) and warm-wet (July). Average noon-time albedo was higher for SU than for CO (0.14 vs. 0.11). Soil heat flux was on average 13% and 12% of net radiation for SU and CO, respectively. Preliminary turbulent flux calculations indicate that noon-time Bowen ratio was higher for sugar cane (range: 1.0-1.5) compared to shaded coffee (range: 0.5-1.0). Seasonal (and crop-stage) changes affected the surface parameters of SU mostly. For example, the SU Bowen ratio increased with decreasing soil moisture, indicating soil moisture limitation for transpiration reducing latent heat flux. In contrast, the shaded coffee Bowen ratio remained relatively constant across measuring periods. The energy balance closure was 80% (pending complete eddy covariance data corrections). These results indicate that the conversion of shaded coffee to sugarcane result in a drier and hotter lower atmosphere. Next steps include examining the implications of these local changes for regional climate, with special attention to cloud formation, using a regional model

  19. Coverage Error of Three Conceptually Different Shade Guide Systems to Vital Unrestored Dentition

    PubMed Central

    Bayindir, Funda; Kuo, Shanglun; Johnston, William M.; Wee, Alvin G.

    2007-01-01

    Statement of problem It remains unclear which shade guide system is most representative of the shades found in the human dentition. Purpose The purpose of this study was to determine and to compare the coverage errors (CEs) of 3 different shades in a selected population. Material and methods The coverage errors of the following shade guide systems were evaluated to determine which shade guide system is most effective in producing the best visual shade match: (1) Vita Lumin, (2) Chromascop, (3) Vitapan 3D Master, and (4) a combination of the 3 shade guide systems. The spectral reflectance values of the central one ninth (1-mm diameter) of each shade tab (without a backing) were measured with a spectroradiometer and an external light source at wavelengths from 380 nm to 780 nm at 2-nm intervals. All spectral reflectance measurements were made using 0-degree observer and 45-degree illumination and then converted to CIE values. The color values of 359 anterior teeth were measured with the same protocol. The CEs for each of the 359 anterior teeth for each shade guide system, and with all 3 shade guide systems, were determined and averaged. Repeated measure ANOVA was used to evaluate the mean minimum CEs within-subject (shade guide system) and between-subject (age) difference as well as the interaction between these variables (α=.05). Then, a post hoc multiple comparison was performed using the Tukey-Kramer test. Results A significant difference (P<.001) was found among the mean minimum CEs of the 3 shade guide systems and their combination, but not between age groups (P=.384). An interaction was found between shade guide systems and age (P<.001). The Tukey-Kramer test revealed that the mean minimum CEs for Vita Lumin (5.39 ΔE) and Chromoscop (5.28 ΔE) shade guide systems were not significantly different from each other. However, the combination of all 3 shade guide systems (3.69 ΔE) and Vitapan 3D Master (3.93 ΔE) were significantly different from the Vita Lumin

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

    PubMed

    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.

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

    PubMed Central

    Valladares, Fernando; Gianoli, Ernesto; Saldaña, Alfredo

    2011-01-01

    Background and Aims 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. Methods 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. Key Results 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 %). Conclusions 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. PMID:21685433

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

    PubMed

    Zhang, Rui-Hua; Xu, Kun

    2008-03-01

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

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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.

  5. The effect of light-cured nanofilled composite resin shades on their under-surface temperature

    NASA Astrophysics Data System (ADS)

    Hanum, U. A.; Herda, E.; Indrani, D. J.

    2017-08-01

    The objective of this study was to observe the effect of shades of light-cured nanofilled composite resins on their under-surface temperature. Resin composites specimens of shades bright, medium, and dark shade were obtained from a cylindrical mold. While polymerizing using a curing unit, the under-surface temperature was determined at the bottom of the specimens using a thermocouple wire 20 sec after the start. Results showed that the under-surface temperature of the darker shade specimens were relatively higher that those of the brighter shades with significant diffferences between the resin composites of different shades. To conlude, the under-surface temperature of the light-cured nanofilled resin composites raised from the brighter to the darker shades.

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  9. Which offers more scope to suppress river phytoplankton blooms: reducing nutrient pollution or riparian shading?

    PubMed

    Hutchins, M G; Johnson, A C; Deflandre-Vlandas, A; Comber, S; Posen, P; Boorman, D

    2010-10-01

    River flow and quality data, including chlorophyll-a as a surrogate for river phytoplankton biomass, were collated for the River Ouse catchment in NE England, which according to established criteria is a largely unpolluted network. Against these data, a daily river quality model (QUESTOR) was setup and successfully tested. Following a review, a river quality classification scheme based on phytoplankton biomass was proposed. Based on climate change predictions the model indicated that a shift from present day oligotrophic/mesotrophic conditions to a mesotrophic/eutrophic system could occur by 2080. Management options were evaluated to mitigate against this predicted decline in quality. Reducing nutrient pollution was found to be less effective at suppressing phytoplankton growth than the less costly option of establishing riparian shading. In the Swale tributary, ongoing efforts to reduce phosphorus loads in sewage treatment works will only reduce peak (95th percentile) phytoplankton by 11%, whereas a reduction of 44% is possible if riparian tree cover is also implemented. Likewise, in the Ure, whilst reducing nitrate loads by curtailing agriculture in the headwaters may bring about a 10% reduction, riparian shading would instead reduce levels by 47%. Such modelling studies are somewhat limited by insufficient field data but offer a potentially very valuable tool to assess the most cost-effective methods of tackling effects of eutrophication. Copyright 2010 Elsevier B.V. All rights reserved.

  10. Differential leaf expansion can enable hydraulic acclimation to sun and shade.

    PubMed

    Carins Murphy, Madeline R; Jordan, Gregory J; Brodribb, Timothy J

    2012-08-01

    Although leaf size is one of the most responsive plant traits to environmental change, the functional benefits of large versus small leaves remain unclear. We hypothesized that modification of leaf size within species resulting from differences in irradiance can allow leaves to acclimate to different photosynthetic or evaporative conditions while maintaining an efficient balance between hydraulic supply (vein density) and evaporative demand. To test this, we compared the function and anatomy of leaf hydraulic systems in the leaves of a woody angiosperm (Toona ciliata M. Roem.) grown under high and low irradiance in controlled conditions. Our results confirm that in this species, differential leaf expansion regulates the density of veins and stomata such that leaf hydraulic conductance and stomatal conductance remain proportional. A broader sample of field-grown tree species suggested that differences in leaf venation and stomatal traits induced by sun and shade were not regulated by leaf size in all cases. Our results, however, suggest that leaf size plasticity can provide an efficient way for plants to acclimate hydraulic and stomatal conductances to the contrasting evaporative conditions of sun and shade.

  11. SMILE--shaded molecular imaging on low-cost equipment.

    PubMed

    Eufri, D; Sironi, A

    1989-09-01

    The SMILE program runs under MS-DOS on IBM PC AT-compatible computers equipped with the SM640 or the PG640 Matrox graphic board. The program allows real-time three-dimensional (3D) animation and modeling of several isolated molecules that can be built from scratch, manipulated interactively and compared by superimposition. SMILE enables users to compute atomic partial charges, molecular surface area, molecular volume, electrostatic and nonbonded potential energies. PLUTO, ORTEP, and MMP2 input files are set up automatically. The program also provides simple access to crystal packing by real-time animation of the unit cell contents, interactive inspection of the relevant stereochemical parameters and fragment manipulation within the unit cell. SMILE animates stereo views and produces beautiful shaded 3D images (8 colors, 32 shades each) of molecules in many different styles--stick, ball-and-stick, CPK (space filling), and transparent CPK with backbone.

  12. Color stability of shade guides after autoclave sterilization.

    PubMed

    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.

  13. Balancing solar shading, daylighting and glare with translucent louvers

    SciTech Connect

    Jackaway, A.; Davies, M.

    1997-12-31

    Successful design of comfortable low-energy office buildings implicitly requires careful consideration for solar shading, daylighting, and the control of glare. Yet these inherently intertwined issues often demand conflicting design responses that pose difficult challenges for designers who frequently discover that successfully addressing one issue means sacrificing the performance with another. This is most commonly observed when excessive shading and glare control strategies reduce interior daylighting so significantly that electric lighting is operated at full capacity directly adjacent to fully glazed facades. The new Phoenix office building at England`s Building Research Establishment (BRE) employs an operable external translucent louver system along its southern facade to achieve a reasonable balance of these issues without significantly sacrificing individual performance. This paper describes the configuration and developmental processes for this system.

  14. Prediction of large negative shaded-side spacecraft potentials

    NASA Technical Reports Server (NTRS)

    Prokopenko, S. M. L.; Laframboise, J. G.

    1977-01-01

    A calculation by Knott, for the floating potential of a spherically symmetric synchronous-altitude satellite in eclipse, was adapted to provide simple calculations of upper bounds on negative potentials which may be achieved by electrically isolated shaded surfaces on spacecraft in sunlight. Large (approximately 60 percent) increases in predicted negative shaded-side potentials are obtained. To investigate effective potential barrier or angular momentum selection effects due to the presence of less negative sunlit-side or adjacent surface potentials, these expressions were replaced by the ion random current, which is a lower bound for convex surfaces when such effects become very severe. Further large increases in predicted negative potentials were obtained, amounting to a doubling in some cases.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Quality and Quantity Evaluations of Shade Grown Forages

    Treesearch

    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...

  17. Shaded relief map of US topography from digital elevations

    USGS Publications Warehouse

    Pike, R.J.; Thelin, G.P.

    1989-01-01

    Much geologic and geophysical information that lies encoded within land surface form can be revealed by image processing large files of digitized elevations in fast machines and mapping the results. This convergence of computers, analytic software, data, and output devices has created exciting opportunities for automating the numerical and spatial study of topography. One recent result is the accompanying shaded relief map of the conterminous 48 states. -from Authors

  18. Cascading indirect effects in a coffee agroecosystem: effects of parasitic phorid flies on ants and the coffee berry borer in a high-shade and low-shade habitat.

    PubMed

    Pardee, Gabriella L; Philpott, Stacy M

    2011-06-01

    Nonconsumptive effects (NCE) of parasites on hosts vary with habitat complexity thereby modifying trait-mediated effects on lower trophic levels. In coffee agroecosystems, Pseudacteon sp. phorid fly parasites negatively affect Azteca instabilis F. Smith ants via NCE thereby indirectly benefiting prey. It is unknown how differences in habitat complexity influence Azteca-phorid interactions or how phorids affect the coffee berry borer (Hypothenemus hampei Ferrari), an important pest of coffee (Coffea arabica L). We tested the following hypotheses in field and lab experiments to find the impact of NCE of phorids on A. instabilis and trait-mediated indirect effects of phorids on the coffee berry borer: (1) Phorid effects on A. instabilis differ between complex and simple shade habitats and (2) Phorids, by modifying A. instabilis behavior, indirectly affect coffee berry borer abilities to invade coffee berries. Phorids had greater impacts on A. instabilis activity in low-shade farms, but differences in phorid impacts were not mediated by phorid density or light availability. In the lab, phorids had strong cascading effects on abilities of A. instabilis to deter coffee berry borers. Without phorids, A. instabilis limited coffee berry borer attacks, whereas when the coffee berry borer was alone or with A. instabilis and phorids, more coffee fruits were attacked by coffee berry borer. These results indicate that A. instabilis has stronger biological control potential in high-shade farms, but the exact mechanism deserves further attention.

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

    USGS Publications Warehouse

    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.

  20. Diurnal dependence of growth responses to shade in Arabidopsis: role of hormone, clock, and light signaling.

    PubMed

    Sellaro, Romina; Pacín, Manuel; Casal, Jorge J

    2012-05-01

    We investigated the diurnal dependence of the hypocotyl-growth responses to shade under sunlight-night cycles in Arabidopsis thaliana. Afternoon shade events promoted hypocotyl growth, while morning shade was ineffective. The lhy-D, elf3, lux, pif4 pif5, toc1, and quadruple della mutants retained the response to afternoon shade and the lack of response to morning shade while the lhy cca1 mutant responded to both morning and afternoon shade. The phyB mutant, plants overexpressing the multidrug resistance-like membrane protein ABCB19, and the iaa17/axr3 loss-of-function mutant failed to respond to shade. Transient exposure of sunlight-grown seedlings to synthetic auxin in the afternoon caused a stronger promotion of hypocotyl growth than morning treatments. The promotion of hypocotyl growth by afternoon shade or afternoon auxin required light perceived by phytochrome A or cryptochromes during the previous hours of the photoperiod. Although the ELF4-ELF3-LUX complex, PIF4, PIF5, and DELLA are key players in the generation of diurnal hypocotyl-growth patterns, they exert a minor role in the control of the diurnal pattern of growth responses to shade. We conclude that the strong diurnal dependency of hypocotyl-growth responses to shade relates to the balance between the antagonistic actions of LHY-CCA1 and a light-derived signal.

  1. Annual variation of the angular distribution of the UV beneath public shade structures.

    PubMed

    Turnbull, D J; Parisi, A V

    2004-10-25

    Local governments provide many shade structures at parks and sporting ovals for public use. However, the question remains of how effective are public shade structures at reducing biologically effective UV radiation throughout the year? Broadband measurements of the angular distribution of scattered UV beneath three specific public shade structures was conducted for relatively clear skies and for a solar zenith angle (SZA) ranging from 13 degrees to 76 degrees. The ultraviolet protection factors (UPF) for the shade structures ranged from 18.3 to 1.5 for an increasing SZA. Measurements showed that the horizontal plane received the highest SUV levels from the SZA of 28 degrees to 75 degrees, 42 degrees to 76 degrees, and 50 degrees to 76 degrees for the small, medium and large structures, respectively. This was due to the angle of the sun causing the shade created by the shade structure to be outside the structure. For the small shade structure, the measurements directed to the west were the highest levels in the shade after approximately 28 degrees. For the medium and large shade structures, the measurements directed to the west and south were the highest levels in the shade after roughly 42 degrees and 50 degrees, respectively.

  2. [Effects of shading on the nitrogen redistribution in wheat plant and the wheat grain quality].

    PubMed

    Mu, Hui-rong; Jiang, Dong; Dai, Ting-bo; Cao, Wei-xing

    2010-07-01

    Taking winter wheat (Triticum aestivum L.) cultivars Yangmai 158 (shading-tolerant) and Yangmai 11 (shading-sensitive) as test materials, this paper studied the effects of shading at the stages from jointing to maturity on the plant N redistribution, grain yield, and grain- and dough quality of the cultivars. The treatments were non-shading, 22% shading, and 33% shading. Under shading, the grain yield and its protein content of Yangmai 158 and Yangmai 11 decreased by 4.1%-9.9% and 3.0%-8.3%, and 15.3%-25.8% and 10.4%-14.1%, respectively, compared with non-shading. With the increase of shading intensity, the grain N content was increasingly dependent on the N accumulated after anthesis. Shading decreased the redistribution of N stored pre-anthesis in the vegetative organs to the grain, but increased the redistribution efficiency of N accumulated pre-anthesis (RENP) in leaves while decreased the RENP in sheathes and stems, and in hulls and rachises. Therefore, the mean RENP in the vegetative organs was not essentially altered by shading. The grain protein content increased significantly under shading, which could be related to the "condense effect", i.e., the decrement of grain protein content was much less than that of grain yield. In addition, shading had less effects on the contents of grain albumin and globulin but increased the contents of grain gliadin and glutinin significantly, and accordingly, the grain wet gluten content, dough development time, and dough stability time increased, while the dough softening degree decreased.

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

    NASA Astrophysics Data System (ADS)

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

    2010-09-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2010-11-01

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

  5. Effects of water level, shade and time on germination and growth of freshwater marsh plants along a simulated successional gradient

    USGS Publications Warehouse

    Kellogg, C.H.; Bridgham, S.D.; Leicht, S.A.

    2003-01-01

    1. We examined the effect of soil organic content (1.4, 3.6, 7.2% soil C), water level (+2, -1, -4 cm from soil surface) and duration (13 or 33 days) on 10 species that varied in abundance during succession in freshwater marshes. We also determined the effect of shade (0, 40, 80% shade) and soil organic content (1.4 and 7.2% soil C) on germination of six species over 62 days with water 0.5 cm below the soil surface. 2. Water level consistently affected species germination on both dates. Above-ground biomass was generally higher with increasing organic content of soil, but shade had little effect on germination or height. 3 The hydrologic zone in which species were found in the field was a good indicator of the response of germination to hydrology. Both early successional species and species wide-spread across the successional gradient show similar germination on all organic contents, while later successional species appear to germinate best at higher organic contents. 4. Successional changes in soils are capable of affecting plant community development, independent of disturbance.

  6. Photosynthetic flexibility in maize exposed to salinity and shade

    PubMed Central

    Sharwood, Robert E.; Sonawane, Balasaheb V.; Ghannoum, Oula

    2014-01-01

    C4 photosynthesis involves a close collaboration of the C3 and C4 metabolic cycles across the mesophyll and bundle-sheath cells. This study investigated the coordination of C4 photosynthesis in maize plants subjected to two salinity (50 and 100mM NaCl) treatments and one shade (20% of full sunlight) treatment. Photosynthetic efficiency was probed by combining leaf gas-exchange measurements with carbon isotope discrimination and assaying the key carboxylases [ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC)] and decarboxylases [nicotinamide adenine dinucleotide phosphate malic enzyme (NADP-ME) and phosphoenolpyruvate carboxykinase (PEP-CK)] operating in maize leaves. Generally, salinity inhibited plant growth and photosynthesis to a lesser extent than shade. Salinity reduced photosynthesis primarily by reducing stomatal conductance and secondarily by equally reducing Rubisco and PEPC activities; the decarboxylases were inhibited more than the carboxylases. Salinity increased photosynthetic carbon isotope discrimination (Δp) and reduced leaf dry-matter carbon isotope composition (13δ) due to changes in p i/p a (intercellular to ambient CO2 partial pressure), while CO2 leakiness out of the bundle sheath (ϕ) was similar to that in control plants. Acclimation to shade was underpinned by a greater downregulation of PEPC relative to Rubisco activity, and a lesser inhibition of NADP-ME (primary decarboxylase) relative to PEP-CK (secondary decarboxylase). Shade reduced Δp and ɸ without significantly affecting leaf 13δ or p i/p a relative to control plants. Accordingly, shade perturbed the balance between the C3 and C4 cycles during photosynthesis in maize, and demonstrated the flexible partitioning of C4 acid decarboxylation activity between NADP-ME and PEP-CK in response to the environment. This study highlights the need to improve our understanding of the links between leaf 13δ and photosynthetic Δp, and the role

  7. Photosynthetic flexibility in maize exposed to salinity and shade.

    PubMed

    Sharwood, Robert E; Sonawane, Balasaheb V; Ghannoum, Oula

    2014-07-01

    C4 photosynthesis involves a close collaboration of the C3 and C4 metabolic cycles across the mesophyll and bundle-sheath cells. This study investigated the coordination of C4 photosynthesis in maize plants subjected to two salinity (50 and 100mM NaCl) treatments and one shade (20% of full sunlight) treatment. Photosynthetic efficiency was probed by combining leaf gas-exchange measurements with carbon isotope discrimination and assaying the key carboxylases [ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC)] and decarboxylases [nicotinamide adenine dinucleotide phosphate malic enzyme (NADP-ME) and phosphoenolpyruvate carboxykinase (PEP-CK)] operating in maize leaves. Generally, salinity inhibited plant growth and photosynthesis to a lesser extent than shade. Salinity reduced photosynthesis primarily by reducing stomatal conductance and secondarily by equally reducing Rubisco and PEPC activities; the decarboxylases were inhibited more than the carboxylases. Salinity increased photosynthetic carbon isotope discrimination (Δp) and reduced leaf dry-matter carbon isotope composition ((13)δ) due to changes in p i/p a (intercellular to ambient CO2 partial pressure), while CO2 leakiness out of the bundle sheath (ϕ) was similar to that in control plants. Acclimation to shade was underpinned by a greater downregulation of PEPC relative to Rubisco activity, and a lesser inhibition of NADP-ME (primary decarboxylase) relative to PEP-CK (secondary decarboxylase). Shade reduced Δp and ɸ without significantly affecting leaf (13)δ or p i/p a relative to control plants. Accordingly, shade perturbed the balance between the C3 and C4 cycles during photosynthesis in maize, and demonstrated the flexible partitioning of C4 acid decarboxylation activity between NADP-ME and PEP-CK in response to the environment. This study highlights the need to improve our understanding of the links between leaf (13)δ and photosynthetic Δp, and

  8. Influence of light source, polarization, education, and training on shade matching quality.

    PubMed

    Clary, Jacqueline A; Ontiveros, Joe C; Cron, Stanley G; Paravina, Rade D

    2016-07-01

    Many factors influence the quality of shade selection, and isolating how significantly each of these factors influences results is difficult. The purpose of this in vitro study was to compare results of shade matching using handheld lights with or without a polarizing filter with results obtained using a professional viewing booth and to analyze the influence of education and training on shade selection outcome. A total of 96 third-year dental students (evaluators) were randomly separated into 4 groups. Each group was assigned 1 of 2 handheld shade-matching devices (lights) with or without a polarizing filter. Each group performed a shade matching exercise using the handheld light or a professional viewing booth. The exercise consisted of matching shade tabs placed in a typodont to a commercial shade guide. Each group repeated this procedure 4 times over a 9-week period. A lecture on shade matching was presented at the fifth week of the study, between "before" and "after" shade matching procedures. Shade matching scores with handheld lights (7.8) were higher than scores of shade matching with the viewing booth (7.2). The mean scores for before (7.2) and after (7.8) shade matching (with education and training in between) were significantly different. The combined effect of light and education and training improved the shade matching score by 1.2, from 6.8 in the before sessions using the viewing booth to 8.0 in the after sessions using handheld lights. A 21% increase in the number of evaluators who selected 1 of 4 best matches was recorded, 10% for handheld lights versus viewing booth after education and training versus before sessions and 11% between after sessions using handheld lights versus before sessions using viewing booth. Within the limits of the study, the shade matching scores with handheld lights were significantly better than the results obtained using a viewing booth (P<.01). Using a handheld light with or without a polarizing filter did not influence

  9. The Effects of Drought and Shade on the Performance, Morphology and Physiology of Ghanaian Tree Species

    PubMed Central

    Amissah, Lucy; Mohren, Godefridus M. J.; Kyereh, Boateng; Poorter, Lourens

    2015-01-01

    In tropical forests light and water availability are the most important factors for seedling growth and survival but an increasing frequency of drought may affect tree regeneration. One central question is whether drought and shade have interactive effects on seedling growth and survival. Here, we present results of a greenhouse experiment, in which seedlings of 10 Ghanaian tree species were exposed to combinations of strong seasonal drought (continuous watering versus withholding water for nine weeks) and shade (5% irradiance versus 20% irradiance). We evaluated the effects of drought and shade on seedling survival and growth and plasticity of 11 underlying traits related to biomass allocation, morphology and physiology. Seedling survival under dry conditions was higher in shade than in high light, thus providing support for the “facilitation hypothesis” that shade enhances plant performance through improved microclimatic conditions, and rejecting the trade-off hypothesis that drought should have stronger impact in shade because of reduced root investment. Shaded plants had low biomass fraction in roots, in line with the trade-off hypothesis, but they compensated for this with a higher specific root length (i.e., root length per unit root mass), resulting in a similar root length per plant mass and, hence, similar water uptake capacity as high-light plants. The majority (60%) of traits studied responded independently to drought and shade, indicating that within species shade- and drought tolerances are not in trade-off, but largely uncoupled. When individual species responses were analysed, then for most of the traits only one to three species showed significant interactive effects between drought and shade. The uncoupled response of most species to drought and shade should provide ample opportunity for niche differentiation and species coexistence under a range of water and light conditions. Overall our greenhouse results suggest that, in the absence of root

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

    PubMed

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

    2017-05-01

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

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

    PubMed

    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.

  12. Occurrence patterns of facilitation by shade along a water gradient are mediated by species traits

    NASA Astrophysics Data System (ADS)

    Egawa, Chika; Tsuyuzaki, Shiro

    2015-01-01

    In disturbed habitats, shade often has facilitative effects on plants by ameliorating water and thermal stresses. Facilitation by shade tends to increase as water availability decreases. At the same time, several studies have suggested that facilitation by shade is not affected by water status or collapses under extremely dry conditions. We hypothesized that traits of beneficiary plants, specifically, the flexibility in the allocation of biomass between shoots and roots, would mediate variation in the relationship between facilitation by shade and water status. To test this hypothesis, we examined the responses of two bog species to shade under various water conditions in a post-mined peatland. The seeds of Rhynchospora alba and Moliniopsis japonica were sown under three water levels (dry: 53% peat water content, wet: 77%, and control: 71%) × two shading levels (50% shaded and unshaded). The survival, biomass, and biomass allocation between the shoots and roots of the two species were monitored for two years. Shade increased the survival and biomass of both species. However, the facilitation of R. alba by shade was independent of water level, whereas the strength of the facilitative effects on M. japonica increased as water content decreased. R. alba preferentially allocated biomass to roots under dry conditions and was highly drought tolerant. M. japonica did not alter the allocation of its biomass in response to either shade or water level and was drought intolerant. Our results suggest that flexibility in biomass allocation of beneficiary plants mediates occurrence patterns of facilitation by shade along a water gradient. The facilitation of species with inflexible biomass allocation by shade through the amelioration of water stress increases as water availability decreases, whereas the facilitation of species with flexible biomass allocation is independent of water status. Such species-specific facilitation would promote the coexistence of diverse species in a

  13. Technique to Match Gingival Shade when Using Pink Ceramics for Anterior Fixed Implant Prostheses.

    PubMed

    Papaspyridakos, Panos; Amin, Sarah; El-Rafie, Khaled; Weber, Hans-Peter

    2016-04-01

    Use of pink gingival ceramics can reduce the necessity for extensive surgical procedures attempting to restore missing soft and hard tissues in the maxillary esthetic zone. Selecting the appropriate shade for pink porcelain poses a challenge, especially when the patient presents with a high smile line. This paper describes a simple and effective technique to facilitate shade selection for gingival ceramics to match the patient's existing gingival shade.

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

    PubMed Central

    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. PMID:26927428

  15. The effects of drought and shade on the performance, morphology and physiology of Ghanaian tree species.

    PubMed

    Amissah, Lucy; Mohren, Godefridus M J; Kyereh, Boateng; Poorter, Lourens

    2015-01-01

    In tropical forests light and water availability are the most important factors for seedling growth and survival but an increasing frequency of drought may affect tree regeneration. One central question is whether drought and shade have interactive effects on seedling growth and survival. Here, we present results of a greenhouse experiment, in which seedlings of 10 Ghanaian tree species were exposed to combinations of strong seasonal drought (continuous watering versus withholding water for nine weeks) and shade (5% irradiance versus 20% irradiance). We evaluated the effects of drought and shade on seedling survival and growth and plasticity of 11 underlying traits related to biomass allocation, morphology and physiology. Seedling survival under dry conditions was higher in shade than in high light, thus providing support for the "facilitation hypothesis" that shade enhances plant performance through improved microclimatic conditions, and rejecting the trade-off hypothesis that drought should have stronger impact in shade because of reduced root investment. Shaded plants had low biomass fraction in roots, in line with the trade-off hypothesis, but they compensated for this with a higher specific root length (i.e., root length per unit root mass), resulting in a similar root length per plant mass and, hence, similar water uptake capacity as high-light plants. The majority (60%) of traits studied responded independently to drought and shade, indicating that within species shade- and drought tolerances are not in trade-off, but largely uncoupled. When individual species responses were analysed, then for most of the traits only one to three species showed significant interactive effects between drought and shade. The uncoupled response of most species to drought and shade should provide ample opportunity for niche differentiation and species coexistence under a range of water and light conditions. Overall our greenhouse results suggest that, in the absence of root

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

    Treesearch

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

    2017-01-01

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

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

    Treesearch

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

    2017-01-01

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

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

    SciTech Connect

    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.

  19. Shade avoidance components and pathways in adult plants revealed by phenotypic profiling.

    PubMed

    Nozue, Kazunari; Tat, An V; Kumar Devisetty, Upendra; Robinson, Matthew; Mumbach, Maxwell R; Ichihashi, Yasunori; Lekkala, Saradadevi; Maloof, Julin N

    2015-04-01

    Shade from neighboring plants limits light for photosynthesis; as a consequence, plants have a variety of strategies to avoid canopy shade and compete with their neighbors for light. Collectively the response to foliar shade is called the shade avoidance syndrome (SAS). The SAS includes elongation of a variety of organs, acceleration of flowering time, and additional physiological responses, which are seen throughout the plant life cycle. However, current mechanistic knowledge is mainly limited to shade-induced elongation of seedlings. Here we use phenotypic profiling of seedling, leaf, and flowering time traits to untangle complex SAS networks. We used over-representation analysis (ORA) of shade-responsive genes, combined with previous annotation, to logically select 59 known and candidate novel mutants for phenotyping. Our analysis reveals shared and separate pathways for each shade avoidance response. In particular, auxin pathway components were required for shade avoidance responses in hypocotyl, petiole, and flowering time, whereas jasmonic acid pathway components were only required for petiole and flowering time responses. Our phenotypic profiling allowed discovery of seventeen novel shade avoidance mutants. Our results demonstrate that logical selection of mutants increased success of phenotypic profiling to dissect complex traits and discover novel components.

  20. Interactions between auxin, microtubules and XTHs mediate green shade- induced petiole elongation in arabidopsis.

    PubMed

    Sasidharan, Rashmi; Keuskamp, Diederik H; Kooke, Rik; Voesenek, Laurentius A C J; Pierik, Ronald

    2014-01-01

    Plants are highly attuned to translating environmental changes to appropriate modifications in growth. Such phenotypic plasticity is observed in dense vegetations, where shading by neighboring plants, triggers rapid unidirectional shoot growth (shade avoidance), such as petiole elongation, which is partly under the control of auxin. This growth is fuelled by cellular expansion requiring cell-wall modification by proteins such as xyloglucan endotransglucosylase/hydrolases (XTHs). Cortical microtubules (cMTs) are highly dynamic cytoskeletal structures that are also implicated in growth regulation. The objective of this study was to investigate the tripartite interaction between auxin, cMTs and XTHs in shade avoidance. Our results indicate a role for cMTs to control rapid petiole elongation in Arabidopsis during shade avoidance. Genetic and pharmacological perturbation of cMTs obliterated shade-induced growth and led to a reduction in XTH activity as well. Furthermore, the cMT disruption repressed the shade-induced expression of a specific set of XTHs. These XTHs were also regulated by the hormone auxin, an important regulator of plant developmental plasticity and also of several shade avoidance responses. Accordingly, the effect of cMT disruption on the shade enhanced XTH expression could be rescued by auxin application. Based on the results we hypothesize that cMTs can mediate petiole elongation during shade avoidance by regulating the expression of cell wall modifying proteins via control of auxin distribution.

  1. Shade Inhibits Leaf Size by Controlling Cell Proliferation and Enlargement in Soybean.

    PubMed

    Wu, Yushan; Gong, Wanzhuo; Yang, Wenyu

    2017-08-23

    To gain more insight into the physiological function of shade and how shade affects leaf size, we investigated the growth, leaf anatomical structure, hormones and genes expressions in soybean. Soybean seeds were sown in plastic pots and were allowed to germinate and grow for 30 days under shade or full sunlight conditions. Shade treated plants showed significantly increase on stem length and petiole length, and decrease on stem diameters, shoot biomass and its partition to leaf also were significantly lower than that in full sunlight. Smaller and thinner on shade treated leaves than corresponding leaves on full sunlight plants. The decreased leaf size caused by shade was largely attributable to cell proliferation in young leaves and both cell proliferation and enlargement in old leaves. Shade induced the expression of a set of genes related to cell proliferation and/or enlargement, but depended on the developmental stage of leaf. Shade significantly increased the auxin and gibberellin content, and significantly decreased the cytokinin content in young, middle and old leaves. Taken together, these results indicated that shade inhibited leaf size by controlling cell proliferation and enlargement, auxin, gibberellin and cytokinin may play important roles in this process.

  2. Shade Avoidance Components and Pathways in Adult Plants Revealed by Phenotypic Profiling

    PubMed Central

    Nozue, Kazunari; Tat, An V.; Kumar Devisetty, Upendra; Robinson, Matthew; Mumbach, Maxwell R.; Ichihashi, Yasunori; Lekkala, Saradadevi; Maloof, Julin N.

    2015-01-01

    Shade from neighboring plants limits light for photosynthesis; as a consequence, plants have a variety of strategies to avoid canopy shade and compete with their neighbors for light. Collectively the response to foliar shade is called the shade avoidance syndrome (SAS). The SAS includes elongation of a variety of organs, acceleration of flowering time, and additional physiological responses, which are seen throughout the plant life cycle. However, current mechanistic knowledge is mainly limited to shade-induced elongation of seedlings. Here we use phenotypic profiling of seedling, leaf, and flowering time traits to untangle complex SAS networks. We used over-representation analysis (ORA) of shade-responsive genes, combined with previous annotation, to logically select 59 known and candidate novel mutants for phenotyping. Our analysis reveals shared and separate pathways for each shade avoidance response. In particular, auxin pathway components were required for shade avoidance responses in hypocotyl, petiole, and flowering time, whereas jasmonic acid pathway components were only required for petiole and flowering time responses. Our phenotypic profiling allowed discovery of seventeen novel shade avoidance mutants. Our results demonstrate that logical selection of mutants increased success of phenotypic profiling to dissect complex traits and discover novel components. PMID:25874869

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

    SciTech Connect

    Kapsis, K.; Athienitis, A.K.; Zmeureanu, R.G.; Tzempelikos, A.

    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)

  4. 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.

    PubMed

    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 (P<.001), abutment shade (P<.001), and type of zirconia copings (P<.003) on the final shade of the zirconia restorations were significant. The average ΔE value of Lava specimens (1 mm) between the A2 composite resin and gold alloy abutments 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.

  5. 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

    PubMed Central

    Oh, Seon-Hee

    2015-01-01

    PURPOSE 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. MATERIALS AND METHODS 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. RESULTS The effects of zirconia specimen thickness (P<.001), abutment shade (P<.001), and type of zirconia copings (P<.003) on the final shade of the zirconia restorations were significant. The average ΔE value of Lava specimens (1 mm) between the A2 composite resin and gold alloy abutments was higher (close to the acceptability threshold of 5.5 ΔE) than th ose between the A2 composite resin and other abutments. CONCLUSION This in-vitro study demonstrated that abutment shade, ceramic thickness, and coping type affected the resulting shade of zirconia restorations. PMID:26576252

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

    NASA Astrophysics Data System (ADS)

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

    2010-12-01

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

  7. Light-Induced Indeterminacy Alters Shade-Avoiding Tomato Leaf Morphology.

    PubMed

    Chitwood, Daniel H; Kumar, Ravi; Ranjan, Aashish; Pelletier, Julie M; Townsley, Brad T; Ichihashi, Yasunori; Martinez, Ciera C; Zumstein, Kristina; Harada, John J; Maloof, Julin N; Sinha, Neelima R

    2015-11-01

    Plants sense the foliar shade of competitors and alter their developmental programs through the shade-avoidance response. Internode and petiole elongation, and changes in overall leaf area and leaf mass per area, are the stereotypical architectural responses to foliar shade in the shoot. However, changes in leaf shape and complexity in response to shade remain incompletely, and qualitatively, described. Using a meta-analysis of more than 18,000 previously published leaflet outlines, we demonstrate that shade avoidance alters leaf shape in domesticated tomato (Solanum lycopersicum) and wild relatives. The effects of shade avoidance on leaf shape are subtle with respect to individual traits but are combinatorially strong. We then seek to describe the developmental origins of shade-induced changes in leaf shape by swapping plants between light treatments. Leaf size is light responsive late into development, but patterning events, such as stomatal index, are irrevocably specified earlier. Observing that shade induces increases in shoot apical meristem size, we then describe gene expression changes in early leaf primordia and the meristem using laser microdissection. We find that in leaf primordia, shade avoidance is not mediated through canonical pathways described in mature organs but rather through the expression of KNOTTED1-LIKE HOMEOBOX and other indeterminacy genes, altering known developmental pathways responsible for patterning leaf shape. We also demonstrate that shade-induced changes in leaf primordium gene expression largely do not overlap with those found in successively initiated leaf primordia, providing evidence against classic hypotheses that shaded leaf morphology results from the prolonged production of juvenile leaf types.

  8. Light-Induced Indeterminacy Alters Shade-Avoiding Tomato Leaf Morphology1[OPEN

    PubMed Central

    Chitwood, Daniel H.; Kumar, Ravi; Ranjan, Aashish; Pelletier, Julie M.; Townsley, Brad T.; Ichihashi, Yasunori; Martinez, Ciera C.; Zumstein, Kristina; Harada, John J.; Maloof, Julin N.; Sinha, Neelima R.

    2015-01-01

    Plants sense the foliar shade of competitors and alter their developmental programs through the shade-avoidance response. Internode and petiole elongation, and changes in overall leaf area and leaf mass per area, are the stereotypical architectural responses to foliar shade in the shoot. However, changes in leaf shape and complexity in response to shade remain incompletely, and qualitatively, described. Using a meta-analysis of more than 18,000 previously published leaflet outlines, we demonstrate that shade avoidance alters leaf shape in domesticated tomato (Solanum lycopersicum) and wild relatives. The effects of shade avoidance on leaf shape are subtle with respect to individual traits but are combinatorially strong. We then seek to describe the developmental origins of shade-induced changes in leaf shape by swapping plants between light treatments. Leaf size is light responsive late into development, but patterning events, such as stomatal index, are irrevocably specified earlier. Observing that shade induces increases in shoot apical meristem size, we then describe gene expression changes in early leaf primordia and the meristem using laser microdissection. We find that in leaf primordia, shade avoidance is not mediated through canonical pathways described in mature organs but rather through the expression of KNOTTED1-LIKE HOMEOBOX and other indeterminacy genes, altering known developmental pathways responsible for patterning leaf shape. We also demonstrate that shade-induced changes in leaf primordium gene expression largely do not overlap with those found in successively initiated leaf primordia, providing evidence against classic hypotheses that shaded leaf morphology results from the prolonged production of juvenile leaf types. PMID:26381315

  9. Evaluation of Cellular Shades in the PNNL Lab Homes

    SciTech Connect

    Petersen, Joseph M.; Sullivan, Greg; Cort, Katherine A.; Metzger, Cheryn E.; Merzouk, Massine

    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.

  10. Riparian shading controls instream spring phytoplankton and benthic algal growth.

    PubMed

    Halliday, S J; Skeffington, R A; Wade, A J; Bowes, M J; Read, D S; Jarvie, H P; Loewenthal, M

    2016-06-15

    Dissolved oxygen (DO) concentrations showed a striking pattern in a multi-year study of the River Enborne, a small river in SE England. In each of three years (2010-2012), maximum DO concentrations were attained in mid-April, preceded by a period of steadily increasing diurnal amplitudes, followed by a steady reduction in both amplitude and concentration. Flow events during the reduction period reduce DO to low concentrations until the following spring. Evidence is presented that this pattern is mainly due to benthic algal growth which is eventually suppressed by the growth of the riparian tree canopy. Nitrate and silicate concentrations are too high to inhibit the growth of either benthic algae or phytoplankton, but phosphate concentrations might have started to reduce growth if the tree canopy development had been delayed. This interpretation is supported by evidence from weekly flow cytometry measurements and analysis of the diurnal, seasonal and annual patterns of nutrient concentrations. As the tree canopy develops, the river switches from an autotrophic to a heterotrophic state. The results support the use of riparian shading to help control algal growth, and highlight the risks of reducing riparian shade.

  11. SKYLAB (SL)-I - MANUFACTURING (SUN SHADE) - GE, HOUSTON, TX

    NASA Image and Video Library

    1973-05-18

    S73-26047 (18 May 1973) --- A sail-like sunshade for possible use as a sunscreen for the Skylab orbital workshop (OWS) is shown being fabricated in the GE Building across the street from the Johnson Space Center. Three persons assist the seamstress feed the material through the sewing machine. The three-layered shade will be composed of a top layer of aluminum Mylar, a middle layer of laminated nylon rip stop, and a bottom layer of thin nylon. Working on the sunshade, from left to right, are Dale Gentry, Elizabeth Gauldin, Alyene Baker and James H. Barnett Jr. Mrs. Baker, a GE employee, operates the double-needle sewing machine. Barnett is head of the Crew Equipment Development Section of JSC's Crew Systems Division. Mrs. Gauldin is also with the Crew Systems Division. Gentry works for GE. The work shown here is part of the crash program underway to prepare a protection device for Skylab to replace the original shield which was lost when the unmanned Skylab 1 launch took place on May 14, 1973. The improvised solar shield selected to be used will be carried to Earth orbit by the Skylab 2 crew, who will deploy it to shade part of the OWS from the hot rays of the sun. Loss of the original shield, as expected, has caused an overheating problem on the OWS. Photo credit: NASA

  12. Depth Structure from Asymmetric Shading Supports Face Discrimination

    PubMed Central

    Chen, Chien-Chung; Chen, Chin-Mei; Tyler, Christopher W.

    2013-01-01

    To examine the effect of illumination direction on the ability of observers to discriminate between faces, we manipulated the direction of illumination on scanned 3D face models. In order to dissociate the surface reflectance and illumination components of front-view face images, we introduce a symmetry algorithm that can separate the symmetric and asymmetric components of the face in both low and high spatial frequency bands. Based on this approach, hybrid faces stimuli were constructed with different combinations of symmetric and asymmetric spatial content. Discrimination results with these images showed that asymmetric illumination information biased face perception toward the structure of the shading component, while the symmetric illumination information had little, if any, effect. Measures of perceived depth showed that this property increased systematically with the asymmetric but not the symmetric low spatial frequency component. Together, these results suggest that (1) the asymmetric 3D shading information dramatically affects both the perceived facial information and the perceived depth of the facial structure; and (2) these effects both increase as the illumination direction is shifted to the side. Thus, our results support the hypothesis that face processing has a strong 3D component. PMID:23457484

  13. How shape from contours affects shape from shading.

    PubMed

    Todorović, Dejan

    2014-10-01

    The spatial pattern of reflected light carries detailed but ambiguous information about 3D shapes of illuminated objects. A little studied factor that affects the perceived 3D relief of 2D shaded figures is the shape of their contours. An experiment is reported in which 102 subjects matched twelve contoured grating displays (horizontal three-cycle gratings with variously shaped top and bottom contours) with perspective line drawings of different 3D shapes, and also judged their depth extent and direction of illumination. The results showed that contour shapes can have surprisingly strong and salient effects on perceived relief. For each display there was a dominant matching drawing, chosen by the largest percentage of subjects, which varied from 95% to 26% across the set of displays. The luminance distribution of contoured gratings is essentially 1D, so that, compared to the general 2D case, their mathematical analysis is considerably simplified, and shape can in certain cases be recovered from shading in analytical form, yielding a three-parameter family of solutions. An analysis of subject responses showed that most reported reliefs had shapes which were closely related to members of the solution family. Furthermore, the particular perceived shapes of contoured gratings could with some success be predicted from the shapes of their contours, based on a simple shape-from-contours rule. However, the data also indicated the presence of a convexity tendency, independent from contour shape.

  14. A two-level generative model for cloth representation and shape from shading.

    PubMed

    Han, Feng; Zhu, Song-Chun

    2007-07-01

    In this paper, we present a two-level generative model for representing the images and surface depth maps of drapery and clothes. The upper level consists of a number of folds which will generate the high contrast (ridge) areas with a dictionary of shading primitives (for 2D images) and fold primitives (for 3D depth maps). These primitives are represented in parametric forms and are learned in a supervised learning phase using 3D surfaces of clothes acquired through photometric stereo. The lower level consists of the remaining flat areas which fill between the folds with a smoothness prior (Markov random field). We show that the classical ill-posed problem-shape from shading (SFS) can be much improved by this two-level model for its reduced dimensionality and incorporation of middle-level visual knowledge, i.e., the dictionary of primitives. Given an input image, we first infer the folds and compute a sketch graph using a sketch pursuit algorithm as in the primal sketch [10], [11]. The 3D folds are estimated by parameter fitting using the fold dictionary and they form the "skeleton" of the drapery/cloth surfaces. Then, the lower level is computed by conventional SFS method using the fold areas as boundary conditions. The two levels interact at the final stage by optimizing a joint Bayesian posterior probability on the depth map. We show a number of experiments which demonstrate more robust results in comparison with state-of-the-art work. In a broader scope, our representation can be viewed as a two-level inhomogeneous MRF model which is applicable to general shape-from-X problems. Our study is an attempt to revisit Marr's idea [23] of computing the 2(1/2)D sketch from primal sketch. In a companion paper [2], we study shape from stereo based on a similar two-level generative sketch representation.

  15. 29 CFR 780.505 - Definition of “shade-grown tobacco.”

    Code of Federal Regulations, 2010 CFR

    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...

  16. Douglas-fir in northern California: effects of shade on germination, survival, and growth

    Treesearch

    Rudolph O. Strothmann

    1972-01-01

    Effects of four light intensities on germination, survival, and early growth of Douglas-fir (Pseudotsuga menziesii) were studied on south-facing cutblocks in northwestern California. Tested were four shade intensities: 0, 25, 50, and 75 percent. On seeded spots, 50 percent shade resulted in greatest germination and survival, being significantly...

  17. 29 CFR 780.506 - Dependence of exemption on shade-grown tobacco operations.

    Code of Federal Regulations, 2010 CFR

    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...

  18. Sacramento's parking lot shading ordinance: environmental and economic costs of compliance

    Treesearch

    E.G. McPherson

    2001-01-01

    A survey of 15 Sacramento parking lots and computer modeling were used to evaluate parking capacity and compliance with the 1983 ordinance requiring 50% shade of paved areas (PA) 15 years after development. There were 6% more parking spaces than required by ordinance, and 36% were vacant during peak use periods. Current shade was 14% with 44% of this amount provided by...

  19. Automated analysis of hypocotyl growth dynamics during shade avoidance in Arabidopsis.

    PubMed

    Cole, Benjamin; Kay, Steve A; Chory, Joanne

    2011-03-01

    Plants that are adapted to environments where light is abundant are especially sensitive to competition for light from neighboring vegetation. As a result, these plants initiate a series of changes known as the shade avoidance syndrome, during which plants elongate their stems and petioles at the expense of leaf development. Although the developmental outcomes of exposure to prolonged shade are known, the signaling dynamics during the initial exposure of seedlings to shade is less well studied. Here, we report the development of a new software-based tool, called HyDE (Hypocotyl Determining Engine) to measure hypocotyl lengths of time-resolved image stacks of Arabidopsis wild-type and mutant seedlings. We show that Arabidopsis grows rapidly in response to the shade stimulus, with measurable growth after just 45 min shade exposure. Similar to other mustard species, this growth response occurs in multiple distinct phases, including two phases of rapid growth and one phase of slower growth. Using mutants affected in shade avoidance phenotypes, we demonstrate that most of this early growth requires new auxin biosynthesis via the indole-3-pyruvate pathway. When activity of this pathway is reduced, the first phase of elongation growth is absent, and this is correlated with reduced activity of auxin-regulated genes. Finally, we show that varying shade intensity and duration can affect the shape and magnitude of the growth response, indicating a broad range of the elongation response to shade.

  20. Shade Tolerance of Festuca paradoxa Desv., a Cool-Season Grass Native to North America

    Treesearch

    Nadia Navarrete-Tindall; Larry Mechlin; J. W. Van Sambeek

    2003-01-01

    Paradox grass (Festuca paradoxa Desv.) is a native cool-season grass found in prairies and forest openings. Paradox grass has not been included in tree plantings. To determine paradox grass adaptation to shaded environmmts, we established a pot experiment in the shade laboratory at the University of Missouri Horticulture and Agroforestry Research...

  1. The effects of zilpaterol hydrochloride and shade on blood metabolites of finishing beef steers

    USDA-ARS?s Scientific Manuscript database

    The effects of feeding zilpaterol hydrochloride (ZH) and shade were evaluated on blood metabolites and lung score in finishing beef steers. Cattle were fed 0 or 8.33 mg/kg ZH for 21 d with a 3- or 4-d withdrawal before harvest and were housed in open or shaded pens. Blood samples and lung scores w...

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

    PubMed

    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.

  3. A novel high-throughput in vivo molecular screen for shade

    USDA-ARS?s Scientific Manuscript database

    The shade avoidance syndrome (SAS) allows plants to anticipate and avoid shading by neighbouring plants by initiating an elongation growth response. The phytochrome photoreceptors are able to detect a reduction in the red:far red ratio in incident light, the result of selective absorption of red and...

  4. Shades of Pink: Preschoolers Make Meaning in a Reggio-Inspired Classroom

    ERIC Educational Resources Information Center

    Kim, Bo Sun

    2012-01-01

    Shades of Pink study describes how six preschoolers and their teacher engaged in a collaborative learning project through which they learned about the shades of a color--in this case, pink. As the children learned through experimenting and discussing their theories, they represented ideas using art as a tool for discovery and learning. The study…

  5. Importance of Shading to Visitors Selecting a Campsite at Indian Boundary Campground in Tennessee

    Treesearch

    George A. James; Harold K. Cordell

    1970-01-01

    Campers at Indian Boundary Campground in Tenr.essee were interviewed during 1966 and 1967 to determine the amount of shading they preferred. The overstory in this campground was selectively thinned several years earlier. This gave campers a choice of campsites, ranging from those so heavily shaded that little sunlight reached the forest floor to...

  6. Effects of shade on the development and sugar metabolism of coffee (Coffea arabica L.) fruits.

    PubMed

    Geromel, Clara; Ferreira, Lúcia Pires; Davrieux, Fabrice; Guyot, Bernard; Ribeyre, Fabienne; Brígida dos Santos Scholz, Maria; Protasio Pereira, Luiz Filipe; Vaast, Philippe; Pot, David; Leroy, Thierry; Androcioli Filho, Armando; Esteves Vieira, Luiz Gonzaga; Mazzafera, Paulo; Marraccini, Pierre

    2008-01-01

    Coffee fruits grown in shade are characterized by larger bean size than those grown under full-sun conditions. The present study assessed the effects of shade on bean characteristics and sugar metabolism by analyzing tissue development, sugar contents, activities of sucrose metabolizing enzymes and expression of sucrose synthase-encoding genes in fruits of coffee (Coffea arabica L.) plants submitted to full-sun (FS) and shade (SH) conditions. Evolution of tissue fresh weights measured in fruits collected regularly from flowering to maturation indicated that this increase is due to greater development of the perisperm tissue in the shade. The effects of light regime on sucrose and reducing sugar (glucose and fructose) contents were studied in fresh and dry coffee beans. Shade led to a significant reduction in sucrose content and to an increase in reducing sugars. In pericarp and perisperm tissues, higher activities of sucrose synthase (EC 2.4.1.13) and sucrose-phosphate synthase (SPS: EC 2.4.1.14) were detected at maturation in the shade compared with full sun. These two enzymes also had higher peaks of activities in developing endosperm under shade than in full sun. It was also noted that shade modified the expression of SUS-encoding genes in coffee beans; CaSUS2 gene transcripts levels were higher in SH than in FS. As no sucrose increase accompanied these changes, this suggests that sucrose metabolism was redirected to other metabolic pathways that need to be identified.

  7. Solar ultraviolet exposures at ground level in tree shade during summer in south east Queensland.

    PubMed

    Parisi, A V; Kimlin, M G; Wong, J C; Wilson, M

    2001-06-01

    Data are presented on the effect of the tree canopy transmittance in the visible waveband (VT), canopy width, height and height of the start of the tree canopy (CH) on the solar UV in tree shade on a horizontal plane at ground level during a Southern Hemisphere summer. Of these factors, the VT and CH have an influence on the UV irradiances in the tree shade. The shade ratios (UV in tree shade to that in full sun) for erythemal UV ranged from 0.71 to 0.42, 0.54 to 0.29 and 0.63 to 0.41 for morning, noon and afternoon, respectively, for the VT range of 0.4-1.0. Over the same VT range, the shade ratios for UVA ranged from 0.61 to 0.28, 0.50 to 0.22 and 0.49 to 0.29 for morning, noon and afternoon, respectively. The UV exposures in the tree shade decreased with the VT with a marginally higher decrease in the irradiances for the UVA compared to the erythemal UV. Despite the protection by the tree shade, significant UV in the tree shade of approximately 4 MED (minimum erythemal dose) were received for the latitude in this research on a cloud free summer day on a horizontal plane over a 2-h period centred about solar noon.

  8. Shades of Pink: Preschoolers Make Meaning in a Reggio-Inspired Classroom

    ERIC Educational Resources Information Center

    Kim, Bo Sun

    2012-01-01

    Shades of Pink study describes how six preschoolers and their teacher engaged in a collaborative learning project through which they learned about the shades of a color--in this case, pink. As the children learned through experimenting and discussing their theories, they represented ideas using art as a tool for discovery and learning. The study…

  9. Radiometer footprint model to estimate sunlit and shaded components for row crops

    USDA-ARS?s Scientific Manuscript database

    This paper describes a geometric model for computing the relative proportion of sunlit vegetation, shaded vegetation, sunlit soil, and shaded soil appearing in a circular or elliptical radiometer footprint for row crops, where the crop rows were modeled as continuous ellipses. The model was validate...

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

    NASA Astrophysics Data System (ADS)

    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 (P<0.01) than the average BGT recorded outside: 35.5 (SD 1.12)°C. Average BGTs in holding pens were 32.4 (SD 1.38) and 39.9 (SD 1.91)°C for shaded and non-shaded areas (P<0.01). The corresponding average floor temperatures were 27.8 (SD 0.68)°C and 47.7 (SD 2.13)°C (P<0.01). To assess the effects of shade on animal well-being, afternoon rectal temperatures (RT) and respiratory rate (respirations per minute, RR) of lactating cows were recorded twice a week. Rectal temperatures were significantly higher for non-shaded cows (P<0.01), mean RT being 40.1 (SD 0.65)°C vs 39.3 (SD 0.42)°C for the shaded animals. Corresponding RRs were 78.9 (SD 18.0) and 60.7 (SD 10.6) (P<0.05). It was concluded that: (1) tree and artificial shades produced similar effects, (2) shading the holding pen with an 80% shading cloth was effective in reducing heat load and floor temperatures, and (3) access to shade in our pasture-based system improved animal well-being.

  11. Characterization of a type II chlorophyll a/b-binding protein gene (Lhcb2*Pp1) in peach. II. mRNA abundance in developing leaves exposed to sun or shade.

    PubMed

    Bassett, Carole L; Callahan, Ann M

    2003-05-01

    Leaf development of shoots exposed to full sunlight and shoots shaded by the canopy was followed in field-grown, mature peach trees (Prunus persica (L.) Batsch, cv. Loring) during the first half of the 1995 growing season. The architecture and size of shaded shoots and sun-exposed shoots differed significantly. Total number of leaves produced on shaded shoots was significantly less than on sun-exposed shoots throughout the season, and differences in leaf number between light conditions increased as the season progressed. The overall patterns of leaf development along sun-exposed and shaded shoots were qualitatively similar. The expression pattern of the type II chlorophyll a/b-binding protein gene, Lhcb2*Pp1, determined by RNA abundance in leaves at different positions along the shoot, was also similar between the two light conditions. The major difference between sun-exposed and shaded leaves was a lower abundance of Lhcb2*Pp1 RNA in mature, shaded leaves compared with sun-exposed leaves. Although the number of fruit per shoot was significantly lower on shaded shoots than on sun-exposed shoots, the rate of fruit drop was not substantially different during the growing season, indicating that quantitative differences in leaf initiation and growth caused by differences in light exposure did not adversely affect fruit retention. However, based on comparison with a previous study of leaf development in non-fruiting trees, reproductive development slowed the rate of vegetative growth without affecting the overall pattern of leaf development along the shoots.

  12. The transcriptional regulator BBX24 impairs DELLA activity to promote shade avoidance in Arabidopsis thaliana.

    PubMed

    Crocco, Carlos D; Locascio, Antonella; Escudero, Cristian M; Alabadí, David; Blázquez, Miguel A; Botto, Javier F

    2015-02-06

    In response to canopy shade, plant vegetative structures elongate to gain access to light. However, the mechanism that allows a plastic transcriptional response to canopy shade light is not fully elucidated. Here we propose that the activity of PIF4, a key transcription factor in the shade signalling network, is modulated by the interplay between the BBX24 transcriptional regulator and DELLA proteins, which are negative regulators of the gibberellin (GA) signalling pathway. We show that GA-related targets are enriched among genes responsive to BBX24 under shade and that the shade-response defect in bbx24 mutants is rescued by a GA treatment that promotes DELLA degradation. BBX24 physically interacts with DELLA proteins and alleviates DELLA-mediated repression of PIF4 activity. The proposed molecular mechanism provides reversible regulation of the activity of a key transcription factor that may prove especially relevant under fluctuating light conditions.

  13. Design of a radiator shade for testing in a simulated lunar environment

    NASA Technical Reports Server (NTRS)

    Huff, Jaimi; Remington, Randy; Tang, Toan

    1992-01-01

    The National Aeronautics and Space Administration (NASA) and The Universities Space Research Association (USRA) have chosen the parabolic/catenary concept from their sponsored Fall 1991 lunar radiation shade project for further testing and development. NASA asked the design team to build a shading device and support structure for testing in a vacuum chamber. Besides the support structure for the catenary shading device, the design team was asked to develop a system for varying the shade shape so that the device can be tested at different focal lengths. The design team developed concept variants and combined the concept variants to form overall designs. Using a decision matrix, an overall design was selected by the team from several overall design alternatives. Concept variants were developed for three primary functions. The three functions were structural support, shape adjustments, and end shielding. The shade adjustment function was divided into two sub-functions, arc length adjustment, and width adjustment.

  14. Native bees mediate long-distance pollen dispersal in a shade coffee landscape mosaic

    PubMed Central

    Jha, Shalene; Dick, Christopher W.

    2010-01-01

    Coffee farms are often embedded within a mosaic of agriculture and forest fragments in the world's most biologically diverse tropical regions. Although shade coffee farms can potentially support native pollinator communities, the degree to which these pollinators facilitate gene flow for native trees is unknown. We examined the role of native bees as vectors of gene flow for a reproductively specialized native tree, Miconia affinis, in a shade coffee and remnant forest landscape mosaic. We demonstrate extensive cross-habitat gene flow by native bees, with pollination events spanning more than 1,800 m. Pollen was carried twice as far within shade coffee habitat as in nearby forest, and trees growing within shade coffee farms received pollen from a far greater number of sires than trees within remnant forest. The study shows that shade coffee habitats support specialized native pollinators that enhance the fecundity and genetic diversity of remnant native trees. PMID:20660738

  15. Under-surface hardness of light-cured nanofilled resin composites of different shades

    NASA Astrophysics Data System (ADS)

    Ramanitya, A.; Indrani, D. J.; Herda, E.

    2017-08-01

    The objective of the this study was to analyze the under-surface hardness of light-cured nanofilled composite resins of different shades. The specimens were resin composites of each light (B1), medium (A3), and dark (C3) shades packed in a cylinder mold and subsequently polymerized. The hardness was tested using a Knoop system. The hardness test results for the bright (B1), medium (A3), and dark (C3) shades were 82.4+1.1, 75.9+1.2 and 65.9+1.9, respectively, and indicated significant differences between the under-surface hardness of each shade. It was concluded that resin composites of darker to brigher shades demonstrated lower to higher under-surface hardness.

  16. Native bees mediate long-distance pollen dispersal in a shade coffee landscape mosaic.

    PubMed

    Jha, Shalene; Dick, Christopher W

    2010-08-03

    Coffee farms are often embedded within a mosaic of agriculture and forest fragments in the world's most biologically diverse tropical regions. Although shade coffee farms can potentially support native pollinator communities, the degree to which these pollinators facilitate gene flow for native trees is unknown. We examined the role of native bees as vectors of gene flow for a reproductively specialized native tree, Miconia affinis, in a shade coffee and remnant forest landscape mosaic. We demonstrate extensive cross-habitat gene flow by native bees, with pollination events spanning more than 1,800 m. Pollen was carried twice as far within shade coffee habitat as in nearby forest, and trees growing within shade coffee farms received pollen from a far greater number of sires than trees within remnant forest. The study shows that shade coffee habitats support specialized native pollinators that enhance the fecundity and genetic diversity of remnant native trees.

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

    NASA Technical Reports Server (NTRS)

    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

  18. Shaded Relief with Color as Height, California Mosaic

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

  1. Shaded Relief with Color as Height, California Mosaic

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This perspective view shows the major volcanic group of Bali, one 13,000 islands comprising the nation of Indonesia. The conical mountain to the left is Gunung Agung, at 3,148 meters (10,308 feet) the highest point on Bali and an object of great significance in Balinese religion and culture. Agung underwent a major eruption in 1963 after more than 100 years of dormancy, resulting in the loss of over 1,000 lives.

    In the center is the complex structure of Batur volcano, showing a caldera (volcanic crater) left over from a massive catastrophic eruption about 30,000 years ago. Judging from the total volume of the outer crater and the volcano, that once lay above it, approximately 140 cubic kilometers(33.4 cubic miles) of material must have been produced by this eruption, making it one of the largest known volcanic events on Earth. Batur is still active and has erupted at least 22 times since the 1800's.

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

  9. Shaded Relief of South Africa, Northern Cape Province

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Located north of the Swartberg Mountains in South Africa's Northern Cape Province, this topographic image shows a portion of the Great Karoo region. Karoo is an indigenous word for 'dry thirst land.' The semi-arid area is known for its unique variety of flora and fauna. The topography of the area, with a total relief of 200 meters (650 feet), reveals much about the geologic history of the area. The linear features seen in the image are near-vertical walls of once-molten rock, or dikes, that have intruded the bedrock. The dikes are more resistant to weathering and, therefore, form the linear wall-like features seen in the image. In relatively flat arid areas such as this, small changes in the topography can have large impacts on the water resources and the local ecosystem. These data can be used by biologists to study the distribution and range of the different plants and animals. Geologists can also use the data to study the geologic history of this area in more detail.

    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

  10. Shaded Relief of South Africa, Northern Cape Province

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Located north of the Swartberg Mountains in South Africa's Northern Cape Province, this topographic image shows a portion of the Great Karoo region. Karoo is an indigenous word for 'dry thirst land.' The semi-arid area is known for its unique variety of flora and fauna. The topography of the area, with a total relief of 200 meters (650 feet), reveals much about the geologic history of the area. The linear features seen in the image are near-vertical walls of once-molten rock, or dikes, that have intruded the bedrock. The dikes are more resistant to weathering and, therefore, form the linear wall-like features seen in the image. In relatively flat arid areas such as this, small changes in the topography can have large impacts on the water resources and the local ecosystem. These data can be used by biologists to study the distribution and range of the different plants and animals. Geologists can also use the data to study the geologic history of this area in more detail.

    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

  11. Shaded Relief Image of Saint Pierre and Miquelon

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This image shows two islands, Miquelon and Saint Pierre, located south of Newfoundland, Canada. These islands, along with five smaller islands, are a self-governing territory of France. A thin barrier beach divides Miquelon, with Grande Miquelon to the north and Petite Miquelonto the south. Saint Pierre Island is located to the lower right. With the islandsi location in the north Atlantic Ocean and their deep water ports, fishing is the major part of the economy. The maximum elevation of the island is 240 meters (787 feet). The land mass of the islands is about 242 square kilometers, or 1.5 times the size of Washington DC.

    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.

    This image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM 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, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASAis Jet Propulsion

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

    NASA Technical Reports Server (NTRS)

    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

  13. Potential energy savings with exterior shades in large office buildings and the impact of discomfort glare

    SciTech Connect

    Hoffmann, Sabine; Lee, Eleanor

    2015-04-01

    Exterior shades are highly efficient for reducing solar load in commercial buildings. Their impact on net energy use depends on the annual energy balance of heating, cooling, fan and lighting energy. This paper discusses the overall energy use intensity of various external shading systems for a prototypical large office building split into the different types of energy use and for different orientations and window sizes. Lighting energy was calculated for a constant lighting power as well as for dimmed lighting fixtures (daylighting control). In Section 3, slat angles and solar cut-off angles were varied for fixed exterior slat shading systems. While the most light-blocking shades performed best for the case without daylighting controls, the optimum cut-off angle with daylighting controls was found to be 30 deg for the office building prototype used in Chicago and Houston. For large window-to-wall (WWR) ratios, window related annual energy use could be reduced by at least 70 % without daylighting control and by a minimum of 86 % with daylighting control in average over all orientations. The occurrence of discomfort glare was is considered in Section 4 of the paper, which looks at the performance of commercially available exterior shading systems when an interior shade is used in addition to the exterior shade during hours when occupants would experience discomfort glare. Glare control impacts overall energy use intensity significantly for exterior shades with high transmittance, especially when daylighting controls are used. In these cases, exterior shades are only beneficial for window-to-wall areas ≥ 45% in the hot Houston climate. For smaller windows and in a heating/cooling climate like Chicago, exterior shades can increase energy consumption

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

    USGS Publications Warehouse

    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.

  15. Moderate shade can increase net gas exchange and reduce photoinhibition in citrus leaves.

    PubMed

    Jifon, John L; Syvertsen, James P

    2003-02-01

    Daily variations in net gas exchange, chlorophyll a fluorescence and water relations of mature, sun-acclimated grapefruit (Citrus paradisi Macfady.) and orange (Citrus sinensis L. Osbeck) leaves were determined in tree canopies either shaded with 50% shade screens or left unshaded (sunlit). Mean daily maximum photosynthetic photon flux density (PPFD) under shade varied from 500 to 700 micromol m-2 s-1 and was sufficient to achieve maximum net CO2 assimilation rates (A CO2). Responses of grapefruit and orange leaves to shading were remarkably similar. At midday, on bright clear days, the temperatures of sunlit leaves were 2-6 degrees C above air temperature and 1-4 degrees C above the temperatures of shaded leaves. Although midday depressions of stomatal conductance (gs) and A CO2 were observed in both sunlit and shaded leaves, shaded leaves had lower leaf-to-air vapor pressure differences (D) along with higher gs, A CO2 and leaf water-use efficiency than sunlit leaves. Estimated stomatal limitation to A CO2 was generally less than 25% and did not differ between shaded and sunlit leaves. Leaf intercellular CO2 partial pressure was not altered by shade treatment and did not change substantially with increasing D. Radiation and high temperature stress-induced non-stomatal limitation to A CO2 in sunlit leaves was greater than 40%. Reversible photoinhibition of photosystem II efficiency was more pronounced in sunlit than in shaded leaves. Thus, non-stomatal factors play a major role in regulating A CO2 of citrus leaves during radiation and high temperature stress.

  16. Dairy cattle prefer shade over sprinklers: effects on behavior and physiology.

    PubMed

    Schütz, K E; Rogers, A R; Cox, N R; Webster, J R; Tucker, C B

    2011-01-01

    Cattle will readily use shade in warm weather, but less is known about voluntary use of sprinklers. We examined preferences of 96 Holstein-Friesian dairy cows (milk yield: 12.7±3.48 kg per day; mean±SD) for sprinklers, shade, or ambient conditions after walking 2.0 km or 0.3 km before afternoon milking (n=48 cows/distance). Each cow was individually tested on 3 consecutive days with a different paired choice each day: 1) shade or sprinklers, 2) shade or ambient conditions, 3) sprinklers or ambient conditions. Average air temperature during testing was 22.3°C. Cows preferred shade over sprinklers (62 vs. 38% ± 5.0%; mean ± SE) and shade over ambient conditions (65 vs. 35% ± 5.1%; mean±SE). Cows showed no preference between sprinklers and ambient conditions (44% of the cows chose sprinklers, SE=5.3%). The preference for shade over sprinklers and ambient conditions increased with air temperature, solar radiation, and wind speed. Walking distance did not influence the preference for any treatment. Respiration rate was decreased most by sprinklers (38% decrease) but also decreased in shade and ambient conditions (17 and 13% decrease, respectively; standard error of the difference=4.7%). Similarly, surface temperature was decreased most by sprinklers (11.4% decrease), compared with that by shade (1.0% decrease), or that by ambient conditions (1.4% increase; standard error of the difference=1.82%). Furthermore, sprinklers reduced insect avoidance behaviors, including number of tail flicks and hoof stamps. In conclusion, dairy cattle preferred to use shade in summer despite sprinklers being more efficient in decreasing heat load and insect avoidance behavior.

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

  20. Shaded Relief Mosaic of Umnak Island, Aleutian Islands, Alaska

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This image is a shaded relief mosaic of Umnak Island in Alaska's Aleutian Islands.

    It was created with Airsar data that was geocoded and combined into this mosaic as part of a NASA-funded Alaska Digital Elevation Model Project at the Alaska Synthetic Aperture Radar Facility (ASF) at the University of Alaska Geophysical Institute in Fairbanks, Alaska.

    Airsar collected the Alaska data as part of its PacRim 2000 Mission, which took the instrument to French Polynesia, American and Western Samoa, Fiji, New Zealand, Australia, New Guinea, Indonesia, Malaysia, Cambodia, Philippines, Taiwan, South Korea, Japan, Northern Marianas, Guam, Palau, Hawaii and Alaska. Airsar, part of NASA's Airborne Science Program, is managed for NASA's Earth Science Enterprise by JPL. JPL is a division of the California Institute of Technology in Pasadena.

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

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Digital elevation models (DEMs), such as those produced by the Shuttle Radar Topography Mission (SRTM), allow user-controlled visualization of the Earth's landforms that is not possible using satellite imagery alone. This three-view comparison shows Los Angeles, Calif., and vicinity, with a Landsat image (only) on the left, a shaded relief rendering of the SRTM DEM on the right, and a merge of the two data sets in the middle. Note that topographic expression in the Landsat image alone is very subtle due to the fairly high sun angle (63 degrees above the horizon) during the satellite overflight in late morning of a mid-Spring day (May 4, 2001). In contrast, computer generated topographic shading of the DEM provides a pure and bold image of topographic expression with a user specified illumination direction. The middle image shows how combining the Landsat and DEM shaded relief can result in a topographically enhanced satellite image in which the information content of both data sets is merged into a single view.

    Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and helps in analyzing the large and growing Landsat image archive, managed by the U.S. Geological Survey (USGS).

    Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA

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

    NASA Technical Reports Server (NTRS)

    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

  3. Light-switching behavior of non-mechanical shading devices

    SciTech Connect

    Koerner, W.; Hauck, S.; Scheller, H.; Beck, A.; Fricke, J.

    1994-12-31

    The authors investigated the light switching properties of non-mechanical shading devices, namely liquid crystal films and thermochromic layers. These systems can be switched between a transparent and a scattering state either by application of an electric voltage or surpassing a characteristic switching temperature. This paper presents data on the light scattering properties of such materials, i.e. the change in diffuse transmittance due to switching, the light scattering efficiency and the size of the scattering entities. Radiative transport calculations were performed in order to describe the light scattering properties of the liquid crystal films and to determine the optimization potential of these layers. For comparison data of an electrochromic layer, which has a transparent and an absorbing state, are shown.

  4. A New RBF Reflection Model for Shape from Shading

    NASA Astrophysics Data System (ADS)

    Yang, Zhi-ming; Zhao, Hong-dong

    2017-09-01

    Radial basis function (RBF) neural network has excellent local mapping and function approximation ability, which is suitable for achieving the optimal solution of nonlinear equations. Due to the direction of the light source is not being estimated accurately by the traditional shape from shading algorithm, in this paper, the RBF neural network is introduced to optimize the classic problem. A RBF reflection model is established to replace the ideal Lambertian reflection model. Then the classic images and two real images are processed using this model without the need of the initial information of the light source. The restored 3D results show that the improved algorithm works better in the details than the traditional algorithm. The errors are much smaller. By adjusting the relevant parameters in RBF reflection model automatically, the training process has been shortened and the convergence rate is improved at the same time.

  5. Preference of domestic horses for shade in a hot, sunny environment.

    PubMed

    Holcomb, K E; Tucker, C B; Stull, C L

    2014-04-01

    Provision of shade is recommended by best practice guidelines for horses living in hot, sunny environments despite a lack of research focused on potential benefits. We found in a previous study that horses without access to shade showed greater rectal temperature (RT), respiration rate (RR), and skin temperature (SK) and exhibited more sweat than horses that were completely shaded. Yet not known is whether horses will choose to stand in the shade when given a choice of areas with and without this resource. Our objective was to assess horse preference for shaded and unshaded areas in the hot and arid, sunny summer weather in Davis, California. For this preference test, 12 healthy, adult horses (6 mares, 6 geldings) were randomized into 3 sequential trials using 4 horses in each trial. The trials consisted of 2 d of acclimation and either 5 d (Trial 1) or 7 d (Trials 2 and 3) of observation. Horses were housed individually in dry lot pens. Half of each pen was covered by an open-sided shade structure. The amount of the pen shaded varied slightly throughout the day with a mean of 50.1% of the pen shaded. Physiological measurements (RT, RR, SK, sweat score) were recorded at 0900, 1230, and 1800 h. Behavioral observations (horses' location relative to shade, time spent walking, foraging, and standing) were recorded at 5-min intervals from 1300 to 1800 h daily and at 10-min intervals from 1800 to 1300 h on alternate days. Insect avoidance behavior was recorded for 1 min/h for each horse. Weather factors were recorded every 5 min, 24 h/d throughout the study; mean daytime ambient temperature was 29 °C ± 5 °C. Data were analyzed using PROC MIXED in SAS. Horses were located in the shade in 7.1% more observations than by chance (SE = 1.3, P < 0.001), with greatest use before and during peak solar radiation and then again following peak black globe temperature. Horses performed more walking and foraging behavior in the shaded areas (P < 0.01). Our research indicates that

  6. Metabolomic analysis using ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF MS) uncovers the effects of light intensity and temperature under shading treatments on the metabolites in tea.

    PubMed

    Zhang, Qunfeng; Shi, Yuanzhi; Ma, Lifeng; Yi, Xiaoyun; Ruan, Jianyun

    2014-01-01

    To investigate the effect of light intensity and temperature on the biosynthesis and accumulation of quality-related metabolites, field grown tea plants were shaded by Black Net and Nano-insulating Film (with additional 2-4°C cooling effect) with un-shaded plants as a control. Young shoots were subjected to UPLC-Q-TOF MS followed by multivariate statistical analysis. Most flavonoid metabolites (mainly flavan-3-ols, flavonols and their glycosides) decreased significantly in the shading treatments, while the contents of chlorophyll, β-carotene, neoxanthin and free amino acids, caffeine, benzoic acid derivatives and phenylpropanoids increased. Comparison between two shading treatments indicated that the lower temperature under Nano shading decreased flavonols and their glycosides but increased accumulation of flavan-3-ols and proanthocyanidins. The comparison also showed a greater effect of temperature on galloylation of catechins than light intensity. Taken together, there might be competition for substrates between the up- and down-stream branches of the phenylpropanoid/flavonoid pathway, which was influenced by light intensity and temperature.

  7. Hypothenemus hampei (Coleoptera: Curculionidae) and its interactions with Azteca instabilis and Pheidole synanthropica (Hymenoptera: Formicidae) in a shade coffee agroecosystem.

    PubMed

    Jiménez-Soto, Estelí; Cruz-Rodríguez, Juan A; Vandermeer, John; Perfecto, Ivette

    2013-10-01

    The coffee berry borer is currently the most important insect pest of coffee worldwide. In shaded coffee farms such as Finca Irlanda in Chiapas, Mexico, natural enemies limit coffee berry borer and potentially prevent outbreaks. This research aimed to determine the effect of ants on coffee berry borer damage and to describe behaviors of Azteca instabilis F. Smith and Pheidole synanthropica (Longino 2009) when encountering the coffee berry borer. To these ends, an ant survey was conducted in a 2,500-m(2) plot within the farm. A 4- by 4-m coordinate system was established, and the coffee plant or shade tree closest to the coordinate point was sampled using tuna fish for a total of 168 coffee plants and 46 shade trees sampled. In addition, up to 100 berries were harvested from 138 coffee plants to measure damage and verify the presence of the coffee berry borer. Behavior was determined in the field by placing live coffee berry borer adults on berries and video recording all attacks. Results showed that plants with ants had less percentage of damaged berries and shorter coffee berry borer galleries than plants without ants. However, the length of galleries in plants with A. instabilis showed no significant differences from plants without ants. P. synanthropica was observed carrying coffee berry borer to the nest in 50% of the cases, whereas A. instabilis threw coffee berry borer off of the coffee plant in 79% of the cases. Results indicate that the presence of these species of ants reduce coffee berry borer damage and suggest that different behaviors could explain the pattern of coffee berry borer attack in this agroecosystem.

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

    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.

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

    PubMed

    Reinert, Fernanda; Leal-Costa, Marcos V; Junqueira, Nícia E; Tavares, Eliana S

    2013-01-01

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

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

    PubMed

    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.

  12. Plasticity to simulated shade is associated with altitude in structured populations of Arabidopsis thaliana.

    PubMed

    Botto, Javier F

    2015-07-01

    Plants compete for photosynthesis light and induce a shade avoidance syndrome (SAS) that confers an important advantage in asymmetric competition for light at high canopy densities. Shade plasticity was studied in a greenhouse experiment cultivating Arabidopsis thaliana plants from 15 populations spread across an altitudinal gradient in the northeast area of Spain that contain a high genetic variation into a reduced geographical range. Plants were exposed to sunlight or simulated shade to identify the range of shade plasticity. Fourteen vegetative, flowering and reproductive traits were measured throughout the life cycle. Shade plasticity in flowering time and dry mass was significantly associated with the altitude of population origin. Plants from coastal populations showed higher shade plasticity indexes than those from mountains. The altitudinal variation in flowering leaf plasticity adjusted negatively with average and minimum temperatures, whereas dry mass plasticity was better explained by negative regressions with the average, maximum and minimum temperatures, and by a positive regression with average precipitation of the population origin. The lack of an altitudinal gradient for the widest number of traits suggests that shade light could be a driver explaining the distribution pattern of individuals in smaller geographical scales than those explored here.

  13. An Appraisal of the Classic Forest Succession Paradigm with the Shade Tolerance Index

    PubMed Central

    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. PMID:25658092

  14. Identifying the tooth shade in group of patients using Vita Easyshade

    PubMed Central

    Elamin, Habab Osman; Abubakr, Neamat Hassan; Ibrahim, Yahia Eltayib

    2015-01-01

    Objective: The aim of the present investigation is to identify tooth shade among a group of Sudanese patients. Materials and Methods: Total number of patients was 227. Participant's age ranged from 15 to 72 years, which, was divided into four groups. The tooth included in the study was either right or left sounds maxillary central incisor. Vita Easyshade was used to select the tooth shade. Investigation of the differences of Commission International de l’Eclairage (CIELab) coordinates among gender and state of origin was conducted together with an examination of the relationship between CIELab coordinates and age. One-way analysis of variance was used to test the differences in L*, a* and b* according to state of origin. Results: Results showed that A3 was the most common classical tooth shade respectively. There was highly significant difference in L* between males and females (P = 0.002). There was a significant relation between tooth shade and age (P = 0.026). There was a high significant association between classical tooth shade and Sudan regions (P = 0.00). Conclusion: In conclusion, most common classical shade was A3, women's teeth were lighter than men's. There was a relation between ethnic background and tooth shade. PMID:26038652

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

    PubMed Central

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

    2009-01-01

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

  16. Penetration of solar erythemal UV radiation in the shade of two common Australian trees.

    PubMed

    Parisi, A V; Willey, A; Kimlin, M G; Wong, J C

    1999-06-01

    The penetration of solar erythemal ultraviolet radiation has been measured in the shade of a gum (Eucalyptus sp.) and a she oak (Casaurina) tree, both on a horizontal plane and with polysulphone dosimeters to human anatomical sites. This has provided new data useful for protection strategies against harmful ultraviolet radiation. For larger solar zenith angles, the relative penetration of solar erythemal ultraviolet in the shade of the trees is higher. On a horizontal plane, at noon, in winter, the shade erythemal ultraviolet ranged from 44 to 55% of that in the sun whereas in spring it ranged from 29 to 37% of the irradiances in the sun. Similarly, at 9:00 EST and 15:00 EST, the shade erythemal ultraviolet in winter ranged from 51 to 81% of the irradiances in the sun whereas in spring and summer they ranged from 35 to 51% of the unshaded irradiances. The shade ratios for specific body sites provided by the shade of the two trees were 0.05 to 0.45 for the solar zenith angles in this research. The shade ratios ranged from 0.14 to 0.45 for the gum tree and from 0.05 to 0.28 for the she oak. The denser foliage of the she oak provided higher ultraviolet protection compared to that of the gum tree.

  17. Prevalence of Colour Vision Anomalies Amongst Dental Professionals and its Effect on Shade Matching of Teeth.

    PubMed

    Khosla, Amrit; Maini, Anuj Paul; Wangoo, Anuj; Singh, Sukhman; Mehar, Damanpreet Kaur

    2017-01-01

    The success of a restoration is dependent on accurate shade matching of teeth leading to studies evaluating the factors affecting the perception of shades. Colour vision anomalies including colour blindness have been found to exist in the population and it has been thought to be a potential factor affecting the colour perception ability. The present study was done to evaluate the prevalence of colour vision anomalies and its effect on matching of shades of teeth. A total of 147 dental professionals were randomly selected for the study and were first tested for visual acuity using the Snellen's Eye Chart so as to carry on the study with only those operators who had a vision of 6/6. Then, the Ishihara's colour charts were used to test the operators for colour vision handicap. In the last stage of the study, test for accuracy of shade selection was done using the Vitapan Classical shade guide. The shade guide tabs were covered to avoid bias. Percentage was used to calculate the prevalence of colour vision handicap and its effect on matching of shades of teeth as compared to normal vision, which was evaluated using Chi square test. Nineteen operators had colour vision anomalies out of hundred operators and only two operators presented with colour blindness. Colour vision anomaly was more prevalent than colour blindness and it was also found that it was more prevalent in males than females. The difference between the accuracy of shade matching between the operators with normal vision and colour vision defect and operators with normal vision and colour blindness was statistically not significant. Colour blindness and colour vision handicap are rare conditions, with the latter being more common in the population. According to our study, it was concluded that no statistically significant difference existed amongst the operators with normal vision and colour vision anomaly or operators with normal vision and colour blindness during the matching of shades of teeth.

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

    PubMed Central

    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

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

    PubMed

    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.

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

    PubMed

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

    2016-01-01

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

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

    PubMed

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

    2013-11-01

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

  2. Seeing the landscape for the trees: Metrics to guide riparian shade management in river catchments

    NASA Astrophysics Data System (ADS)

    Johnson, Matthew F.; Wilby, Robert L.

    2015-05-01

    Rising water temperature (Tw) due to anthropogenic climate change may have serious consequences for river ecosystems. Conservation and/or expansion of riparian shade could counter warming and buy time for ecosystems to adapt. However, sensitivity of river reaches to direct solar radiation is highly heterogeneous in space and time, so benefits of shading are also expected to be site specific. We use a network of high-resolution temperature measurements from two upland rivers in the UK, in conjunction with topographic shade modeling, to assess the relative significance of landscape and riparian shade to the thermal behavior of river reaches. Trees occupy 7% of the study catchments (comparable with the UK national average) yet shade covers 52% of the area and is concentrated along river corridors. Riparian shade is most beneficial for managing Tw at distances 5-20 km downstream from the source of the rivers where discharge is modest, flow is dominated by near-surface hydrological pathways, there is a wide floodplain with little landscape shade, and where cumulative solar exposure times are sufficient to affect Tw. For the rivers studied, we find that approximately 0.5 km of complete shade is necessary to off-set Tw by 1°C during July (the month with peak Tw) at a headwater site; whereas 1.1 km of shade is required 25 km downstream. Further research is needed to assess the integrated effect of future changes in air temperature, sunshine duration, direct solar radiation, and downward diffuse radiation on Tw to help tree planting schemes achieve intended outcomes.

  3. Performance assessment of Vita Easy Shade spectrophotometer on colour measurement of aesthetic dental materials.

    PubMed

    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 < 0.001). However, a high correlation was found (p < 0.001) despite the low concordance noticed. The colour difference deltaE* values calculated between different shades also were significantly different between both spectrophotometers (p < 0.05). Therefore, the Easy Shade can be used in dental practice and dental research with some limitations.

  4. Ontogeny, understorey light interception and simulated carbon gain of juvenile rainforest evergreens differing in shade tolerance

    PubMed Central

    Lusk, Christopher H.; Pérez-Millaqueo, Manuel Matías; Piper, Frida I.; Saldaña, Alfredo

    2011-01-01

    Background and Aims A long-running debate centres on whether shade tolerance of tree seedlings is mainly a function of traits maximizing net carbon gain in low light, or of traits minimizing carbon loss. To test these alternatives, leaf display, light-interception efficiency, and simulated net daily carbon gain of juvenile temperate evergreens of differing shade tolerance were measured, and how these variables are influenced by ontogeny was queried. Methods The biomass distribution of juveniles (17–740 mm tall) of seven temperate rainforest evergreens growing in low (approx. 4 %) light in the understorey of a second-growth stand was quantified. Daytime and night-time gas exchange rates of leaves were also determined, and crown architecture was recorded digitally. YPLANT was used to model light interception and carbon gain. Results An index of species shade tolerance correlated closely with photosynthetic capacities and respiration rates per unit mass of leaves, but only weakly with respiration per unit area. Accumulation of many leaf cohorts by shade-tolerant species meant that their ratios of foliage area to biomass (LAR) decreased more gradually with ontogeny than those of light-demanders, but also increased self-shading; this depressed the foliage silhouette-to-area ratio (STAR), which was used as an index of light-interception efficiency. As a result, displayed leaf area ratio (LARd = LAR × STAR) of large seedlings was not related to species shade tolerance. Self-shading also caused simulated net daily carbon assimilation rates of shade-tolerant species to decrease with ontogeny, leading to a negative correlation of shade tolerance with net daily carbon gain of large (500 mm tall) seedlings in the understorey. Conclusions The results suggest that efficiency of energy capture is not an important correlate of shade tolerance in temperate rainforest evergreens. Ontogenetic increases in self-shading largely nullify the potential carbon gain advantages expected

  5. Effect of time and weather on preference, frequency, and duration of shade use by horses.

    PubMed

    Holcomb, K E; Stull, C L

    2016-04-01

    The Federation of Animal Science Societies (FASS) recommends providing access to shade for horses in hot, sunny weather at equine facilities. Previously, we found that healthy, mature domestic horses use shade with behavioral and physiological benefits during those weather conditions. The objective of this study was to characterize preference, frequency, and duration of shade use by healthy, mature horses in a Bureau of Land Management (BLM) holding facility during hot, sunny weather. The study took place at the BLM's Palomino Valley Wild Horse and Burro Center in Reno, NV, from Aug. 10 to Oct. 1, 2014. Freestanding shade structures were constructed in each of 2 drylot pens with shade cloth covering the top that blocked 98% of UV radiation. A group of 4 mares was placed in each of the 2 pens. After a 2-d acclimation period, data were recorded for 5 d, the horses were moved to the opposite pen, and data collected for an additional 5 d. This schedule was repeated for a total of 4 consecutive trials and 32 horses. Footage from time-lapse cameras was viewed at 10 s intervals between 0930 and 1700 h to record each horse's position relative to shade. Dosimeters secured to horses' halters recorded UV exposure. Automated weather stations recorded daytime ambient temperature (mean 25.9°C [SD 5.8]), relative humidity (mean 25.4% [SD 17.1]), black globe temperature (mean 29.3°C [SD 6.5] in shade and 35.8°C [SD 8.0] in unshaded area), and solar radiation (mean 595 W/m [SD 235]). Horses spent 10.9% more time in shade than by chance ( < 0.0001) within the drylots across all 40 study days. Mean daily time spent in shade was 107.9 min/horse (SD 66.9), comprising 17.1 bouts (SD 12.1) with an average bout length of 6.3 min (SD 3.4). The mean daily UV Index experienced by horses in these partially shaded drylots was 1.52 (SD 0.58) compared with 3.4 (SD 1.5) for a control instrument in the sun. Horses used shade more on the sunniest days and greater than just by chance at all hours

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

    PubMed

    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.

  7. Loss of photosynthetic efficiency in the shade. An Achilles heel for the dense modern stands of our most productive C4 crops?

    PubMed Central

    Pignon, Charles P.; Jaiswal, Deepak; McGrath, Justin M.

    2017-01-01

    Abstract The wild progenitors of major C4 crops grew as individuals subjected to little shading. Today they are grown in dense stands where most leaves are shaded. Do they maintain photosynthetic efficiency in these low light conditions produced by modern cultivation? The apparent maximum quantum yield of CO2 assimilation (ΦCO2max,app), a key determinant of light-limited photosynthesis, has not been systematically studied in field stands of C4 crops. ΦCO2max,app was derived from the initial slope of the response of leaf CO2 uptake (A) to photon flux (Q). Leaf fractional light absorptance (α) was measured to determine the absolute maximum quantum yield of CO2 assimilation on an absorbed light basis (ΦCO2max,abs). Light response curves were determined on sun and shade leaves of 49 field plants of Miscanthus × giganteus and Zea mays following canopy closure. ΦCO2max,app and ΦCO2max,abs declined significantly by 15–27% (P<0.05) with canopy depth. Experimentally, leaf age was shown unlikely to cause this loss. Modeling canopy CO2 assimilation over diurnal courses suggested that the observed decline in ΦCO2max,app with canopy depth costs 10% of potential carbon gain. Overcoming this limitation could substantially increase the productivity of major C4 crops. PMID:28110277

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

    PubMed Central

    Zylinski, Sarah; Osorio, D.; Johnsen, Sonke

    2016-01-01

    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. PMID:26984626

  9. A scaleable methodology for assessing the impacts of urban shade on the summer electricity use of residential homes

    NASA Astrophysics Data System (ADS)

    Taylor, Robert Vanderlei

    Our cities are experiencing unprecedented growth while net global temperatures continue to trend warmer making sustainable urban development and energy conservation pressing public issues. This research explores how urban landscaping -- in particular trees and buildings -- affect summer electricity use in residential homes. I studied the interactions of urban shade and temperature to explore how vegetation distribution and intensity could play a meaningful role in heat mitigation in urban environments. Only a few studies have reconciled modeled electricity savings from tree shade with actual electricity consumption data. This research proposes a methodology for modeling the isolated effects of urban shade (tree shade vs building shade) on buildings' summertime electricity consumption from micro to mesoscales, empirically validating the modeled shade with actual electricity billing data, and comparing the electric energetic impact of tree shade effects with building shade effects. This proposed methodology seeks to resolve three primary research questions: 1) What are the modeled quantities of urban shade associated with the area of interest (AOI)? 2) To what extent do the effects of shading from trees and buildings mitigate summertime heat in the AOI? 2) To what extent do the shade effects from trees and buildings reduce summertime electricity consumption in the AOI?

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

    PubMed

    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).

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

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

    NASA Technical Reports Server (NTRS)

    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

  16. The dynamical influences of cloud shading on simulated supercell thunderstorms

    NASA Astrophysics Data System (ADS)

    Frame, Jeffrey

    2008-10-01

    Numerical simulations of supercell thunderstorms which include parameterized radiative transfer and surface fluxes are performed using the Advanced Regional Prediction System (ARPS) model. The tilted independent column approximation (TICA) is adopted for use in the ARPS model because the existing method of parameterized radiative transfer, the independent column approximation (ICA), permits only the vertical transfer of shortwave radiation. The computed radiative fluxes from both the TICA and ICA are compared to output from a three-dimensional Monte Carlo radiative transfer solver and it is determined that the TICA fluxes more closely match those from the Monte Carlo model than do those from the ICA. Additionally, the TICA is able to capture the extensions of shadows that occur when the solar zenith angle deviates significantly from zero, which cannot be captured by the ICA. The maximum low-level air temperature deficits within the modeled cloud shadows is 1.5 to 2.0 K, which is only about half that previously observed. The loss of strong solar heating of the model surface within the shaded regions cools the surface temperatures, and changes the sign of the sensible heat flux near the edge of the shadow. This stabilizes the model surface layer and suppresses vertical mixing at low levels within the shaded area. This reduction in vertical mixing means that higher momentum air from aloft is prevented from mixing with air near the surface that has lost momentum to surface friction. The net result of this is a shallower, but more intense vertically-sheared layer near the surface. As the supercell's rear-flank gust front propagates into this modified shear layer, the layer of cold outflow air becomes shallower and it accelerates eastward. In the case of a stationary storm, the cold outflow undercuts the updraft and mesocyclone, depriving them of warm and moist inflow, and ultimately weakening the storm. These results are not likely applicable to all simulations of

  17. Perspective view of shaded relief, color as height, Patagonia, Argentina

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This perspective view of Patagonia, Argentina shows a spectacular landscape formed by volcanoes, rivers, and wind. The area is located just east of the narrow range of the Andes Mountains, about 100 kilometers (62 miles) east of the border with Chile. Interesting features include basalt-capped mesas (top) and young volcanic cones (left foreground). Geologists will use SRTM topographic data to study the interaction of volcanic, climatic and erosional processes.

    This shaded relief perspective view 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 1100 meters (3600 feet) of total relief. To emphasize subtle differences in topography, the relief is exaggerated by a factor of 5.

    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 and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) and the German (DLR) and Italian (ASI)space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC

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

    NASA Technical Reports Server (NTRS)

    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

  19. Perspective View with Color-Coded Shaded Relief, Central Panama

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This perspective view shows central Panama, with the remnants of the extinct volcano El Valle in the foreground and the Caribbean Sea in the distance. El Valle underwent an explosive eruption about 3 million years ago, forming a crater 5 kilometers (3.1 miles) across, one of the largest in the Americas. The crater subsequently filled with water forming a huge lake, but about 12,000 years ago a breach at the present site of the waterfall Choro de las Mozas caused it to drain, forming the present valley. Within the crater is the town of El Valle de Anton, whose 600-meter (1,968-foot) elevation and resulting cooler climate make it a popular tourist and vacation site.

    The lake in the distance is Lake Gatun, at the west end of the Panama Canal. The canal itself extends to the southwest (to the right in this northeast facing view) but is hidden by the intervening terrain.

    This shaded relief perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM). 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, and range from green at the lowest elevations to white at the highest elevations.

    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 and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) and the

  20. Proposed shade guide for attached gingiva--a pilot study.

    PubMed

    Ito, Masayasu; Marx, David B; Cheng, Ansgar C; Wee, Alvin G

    2015-04-01

    The purpose of this study was to evaluate the effect of race, age, and gender on Commision Internationale de l'Eclairage Lab color space (CIELAB) values of attached gingival colors. The color coordinates of an optimal proposed attached gingival shade guide were also determined. Participants (n = 120) were recruited to fulfill the following stratification of five age groups: 18-29, 30-39, 40-49, 50-59, and 60-85, with four racial categories (white, black, Asian, and others) and balanced for gender. Reflectance measurements of participants' attached gingiva were made using a spectroradiometer and Xenon arc lamp with a 45/0 optical configuration. A stepwise discriminant analysis was carried out to identify gingival color contribution from race, age, and gender. A hierarchical clustering analysis was used to identify color groups that clustered together. The coverage error of the proposed shade guide was calculated to the original gingival color. The stepwise discriminant analysis showed a statistically significant difference in gingival color contribution from the factors evaluated. Significant influence was found for the race/gender factors (p < 0.05), but not for age. The cluster analysis results revealed three cluster centroids with mean L*a*b* as follows: (1 = 51.0 ± 4.2, 27.7 ± 4.7, 18.3 ± 3.2), (2 = 61.4 ± 4.5, 24.3 ± 4.3, 17.6 ± 2.3), and (3 = 36.1 ± 4.1, 21 ± 4.9, 16 ± 5.2). The coverage errors to the following racial categories were: Asian (ΔE = 6.0 ± 4.8), black (ΔE = 6.7 ± 3.9), others (ΔE = 5.8 ± 2.9), and white (ΔE = 4.6 ± 2.7). The study showed that L*a*b* was significantly affected by race and gender. Clustering analysis was able to identify clusters in 120 participants for three gingival tones. © 2014 by the American College of Prosthodontists.

  1. Perspective view of shaded relief, color as height, Patagonia, Argentina

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This perspective view of Patagonia, Argentina shows a spectacular landscape formed by volcanoes, rivers, and wind. The area is located just east of the narrow range of the Andes Mountains, about 100 kilometers (62 miles) east of the border with Chile. Interesting features include basalt-capped mesas (top) and young volcanic cones (left foreground). Geologists will use SRTM topographic data to study the interaction of volcanic, climatic and erosional processes.

    This shaded relief perspective view 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 1100 meters (3600 feet) of total relief. To emphasize subtle differences in topography, the relief is exaggerated by a factor of 5.

    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 and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) and the German (DLR) and Italian (ASI)space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC

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

    NASA Technical Reports Server (NTRS)

    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

  3. Perspective View with Color-Coded Shaded Relief, Central Panama

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This perspective view shows central Panama, with the remnants of the extinct volcano El Valle in the foreground and the Caribbean Sea in the distance. El Valle underwent an explosive eruption about 3 million years ago, forming a crater 5 kilometers (3.1 miles) across, one of the largest in the Americas. The crater subsequently filled with water forming a huge lake, but about 12,000 years ago a breach at the present site of the waterfall Choro de las Mozas caused it to drain, forming the present valley. Within the crater is the town of El Valle de Anton, whose 600-meter (1,968-foot) elevation and resulting cooler climate make it a popular tourist and vacation site.

    The lake in the distance is Lake Gatun, at the west end of the Panama Canal. The canal itself extends to the southwest (to the right in this northeast facing view) but is hidden by the intervening terrain.

    This shaded relief perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM). 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, and range from green at the lowest elevations to white at the highest elevations.

    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 and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) and the

  4. Perspective View with Color-Coded Shaded Relief, Panama Canal

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This perspective view shows the Panama Canal with the Gulf of Panama in the foreground and the Caribbean Sea in the distance. The canal runs northwest-southeast from the city of Colon on the Atlantic side to Panama City on the Pacific side. Water levels are maintained along its length by three reservoirs, the largest of which is Lake Gatun, visible at the right center of the image. Built by the U.S. Army Corps of Engineers between 1904 and 1914, the canal extends for approximately 50 miles, and is widely considered to be one of the world's great engineering achievements.

    This shaded relief perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM). 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, and range from green at the lowest elevations to white at the highest elevations.

    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 and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) and the German (DLR) and Italian (ASI) space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise, Washington, D.C.

    Size: scale varies in this perspective image Location: 9.0 degrees North latitude, 79.8 degrees West longitude Orientation

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

    NASA Technical Reports Server (NTRS)

    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