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CULTIVO DO TRIGO DUPLO PROPÓSITO EM SISTEMAS SILVIPASTORIS / DUAL PURPOSE WHEAT CROP IN SILVIPASTORAL SYSTEMSKorcelski, Cleiton 23 February 2016 (has links)
Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul / The intercropping between two species of agronomic interest adds more complex research and guidelines, as there is growth, development and resource sharing. When not planned correctly the consortium may bring harm. Thus, silvopastoral systems, characterized by cultivating a consortium of tree species and forage species, can cause production losses due to natural shading tax species in the understory. Seeking to create new alternatives of tree species to compose silvopastoral systems, the objective of this study was to analyze the dual purpose wheat cultivation in different silvopastoral systems. Tree species that comprised the SSP's were red mimosa (Parapiptadenia rigida) canafístula (Peltophorum dubium), eucalyptus (Eucalyptus grandis) and guapuruvu (Schizolobium parahyba), in addition to growing in full sun environment. The dual purpose wheat genotype used was BRS Tarumã (Triticum aestivum). It was observed the change of weather elements, solar radiation, air temperature and relative humidity inside the shaded environments. The reduction in light intensity affected the growth and development of wheat and stimulated culture change morphoanatomic structures to survive this stress. It was observed under shading conditions that wheat plants have increased the number and volume of intercellular spaces, reduced substomatic and cutinização cells. It found an increase in the thickness of paper and reduction in stomatal density. Plants grown in shaded environments had lower values of LAI, staying for shorter periods of time. As a result increase was observed in the same conversion efficiency, however, the end yield of dry matter and grain yield is adversely affected. The leaf emission was affected by the variation in brightness between the environments. Treatments with high transmissivity ensured higher leaf emission in wheat plants. Most phyllochron was observed in shaded environments while growing full sun got much smaller phyllochron values. The variation in the intensity of solar radiation impose changes both morphoanatomic as the growth and development of wheat plants. It is essential for the culture to develop changes in a plant structure in order to acclimatise to the environment with radiation deficit. / O cultivo consorciado entre duas espécies de interesse agronômico agrega pesquisas e direcionamentos mais complexos, pois há o crescimento, desenvolvimento e compartilhamento de recursos. Quando não planejado de forma correta o consórcio pode trazer prejuízos. Assim, os sistemas silvipastoris, caracterizados pelo cultivo em consórcio de espécies arbóreas e espécies forrageiras, podem causar perdas de produção devido ao sombreamento natural imposto sobre a espécie em sub-bosque. Visando à criação de novas alternativas de espécies arbóreas para compor sistemas silvipastoris, o objetivo do trabalho foi analisar o cultivo do trigo duplo propósito em diferentes sistemas silvipastoris. As espécies arbóreas que compuseram os SSP s foram angico vermelho (Parapiptadenia rigida), canafístula (Peltophorum dubium), eucalipto (Eucalyptus grandis) e guapuruvu (Schizolobium parahyba), além do cultivo em ambiente pleno sol. O genótipo de trigo duplo propósito utilizado foi o BRS Tarumã (Triticum aestivum). Foi observado a alteração dos elementos meteorológicos, radiação solar, temperatura do ar e umidade relativa do ar no interior dos ambientes sombreados. A redução na intensidade de luz afetou o crescimento e desenvolvimento do trigo e estimulou a cultura a modificar estruturas morfoanatômicas para sobreviver a esse estresse. Foi observado sob condições de sombreamento, que plantas de trigo aumentaram o número e o volume de espaços intercelulares, câmaras subestomáticas e reduziram a cutinização de células. Constatou-se incremento na espessura de folha e redução na densidade estomática. Plantas cultivadas em ambientes sombreadas obtiveram menores valores de IAF, permanecendo por menor período de tempo. Como consequência foi observado aumento na eficiência de conversão das mesmas, no entanto, a produção final de matéria seca e grãos foi afetada negativamente. A emissão foliar foi afetada pela variação na luminosidade entre os ambientes. Tratamentos com altas transmissividades asseguraram maior emissão foliar em plantas de trigo. Maior filocrono foi observado em ambientes sombreados, enquanto o cultivo pleno sol obteve valores de filocrono bem menores. A variação na intensidade da radiação solar impõe mudanças tanto morfoanatômicas quanto no crescimento e desenvolvimento de plantas de trigo. É fundamental para essa cultura desenvolver mudanças na sua estrutura vegetal com o intuito de aclimatar-se ao ambiente com déficit de radiação.
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Modélisation et optimisation de la croissance de la laitue dans un système agrivoltaïque dynamique / Modeling and optimization of lettuce growth in dynamic agrivoltaic systemsValle, Benoît 26 June 2017 (has links)
L’agrivoltaïque, combinaison de panneaux photovoltaïques et d’une culture sur le même sol, a été proposé en 1982 comme solution au conflit d’usage des sols. Lancé en 2010 à Montpellier, le concept associant panneaux fixes et diverses cultures a fait la preuve d’une productivité combinée de la parcelle améliorée grâce, notamment, à l’acclimatation de la culture à l’ombre. Dans cette thèse, les panneaux fixes ont été échangés par des panneaux orientables au cours de la journée. L’objectif était d’optimiser l’orientation des panneaux pour maximiser la productivité combinée de la parcelle sans pénaliser la culture. Pour cela, la croissance et le développement de laitues ont été analysés en conditions contrôlées et en plein champ sous différentes modalités d’ombrage par panneaux fixes ou mobiles. Les panneaux mobiles ont permis d’améliorer la productivité combinée de la parcelle par rapport à des panneaux fixes, avec un maintien de la production agricole dans certaines conditions. Une approche écophysiologique basée sur le développement de la plante, sa capacité à intercepter et convertir le rayonnement en biomasse, a révélé que les modalités d’ombrage avaient peu d’impact sur la mise en place de la surface foliaire malgré des différences de biomasse accumulée en rapport avec le rayonnement transmis à la plante. Des modifications du développement foliaire ont conduit à une meilleure utilisation du rayonnement transmis lorsque celui-ci était réduit. Ce travail a débouché sur une modélisation de l’impact de l’orientation des panneaux sur la biomasse des laitues permettant d’optimiser le pilotage des panneaux en fonction du scénario climatique et des objectifs de productions. / Agrivoltaic systems, combining solar panels and crops on the same land were proposed in the early 1980’s as a solution to solve land use conflict. Introduced in 2010 in Montpellier, the concept has proven itself associating fixed panels to multiple food crops. Total land productivity was improved, thanks to plant acclimation to shade. In this thesis, fixed panels were replaced with mobile panels, adjustable along the day. The aim of this work was to optimize solar panel orientations to maximise total land productivity without threatening the crop culture. Growth and development of lettuces were analysed in controlled conditions and in the field under several shading conditions by fixed or mobile panels. Total land productivity was improved with mobile panels in comparison with fixed panels, maintaining lettuce yield under certain conditions. Through an ecophysiological approach based on plant development and its ability to intercept and convert light into biomass, the different shading conditions were shown to have a small impact in the plant leaf area dynamic despite large differences in accumulated dry mass associated with transmitted radiation at the plant level. This was due to differences in leaf development resulted in higher use of the transmitted radiation when it was reduced. This study proposed a modelling approach of the incidence of panel orientations on lettuce dry mass at harvest. The model allows an optimisation of solar panels controlling as a function of climate scenario and crop and electricity production objectives.
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Characterizing Sustainable Performance and Human Thermal Comfort in Designed Landscapes of Southwest Desert CitiesJanuary 2016 (has links)
abstract: During summer 2014, a study was conducted as part of the Landscape Architecture Foundation Case Study Investigation to analyze features of three sustainably designed landscapes. Each project was located in a southwest desert city: Civic Space Park in Phoenix, AZ, the Pete V. Domenici US Courthouse Sustainable Landscape Retrofit in Albuquerque, NM, and George "Doc" Cavalliere Park in Scottsdale, AZ. The principal components of each case study were performance benefits that quantified ongoing ecosystem services. Performance benefits were developed from data provided by the designers and collected by the research team. The functionality of environmental, social, and economic sustainable features was evaluated. In southwest desert cities achieving performance benefits such as microclimate cooling often come at the cost of water conservation. In each of these projects such tradeoffs were balanced by prioritizing the project goals and constraints.
During summer 2015, a study was conducted to characterize effects of tree species and shade structures on outdoor human thermal comfort under hot, arid conditions. Motivating the research was the hypothesis that tree species and shade structures will vary in their capacity to improve thermal comfort due to their respective abilities to attenuate solar radiation. Micrometeorological data was collected in full sun and under shade of six landscape tree species and park ramadas in Phoenix, AZ during pre-monsoon summer afternoons. The six landscape tree species included: Arizona ash (Fraxinus velutina Torr.), Mexican palo verde (Parkinsonia aculeata L.), Aleppo pine (Pinus halepensis Mill.), South American mesquite (Prosopis spp. L.), Texas live oak (Quercus virginiana for. fusiformis Mill.), and Chinese elm (Ulmus parvifolia Jacq.). Results showed that the tree species and ramadas were not similarly effective at improving thermal comfort, represented by physiologically equivalent temperature (PET). The difference between PET in full sun and under shade was greater under Fraxinus and Quercus than under Parkinsonia, Prosopis, and ramadas by 2.9-4.3 °C. Radiation was a significant driver of PET (p<0.0001, R2=0.69) and with the exception of ramadas, lower radiation corresponded with lower PET. Variations observed in this study suggest selecting trees or structures that attenuate the most solar radiation is a potential strategy for optimizing PET. / Dissertation/Thesis / Masters Thesis Applied Biological Sciences 2016
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Validação e reprodutibilidade da análise subjetiva no diagnóstico da cor dentária / Validity and reproducibility of the subjective evaluation used for tooth shade diagnosisMeireles, Sônia Saeger 02 October 2006 (has links)
Made available in DSpace on 2014-08-20T14:30:16Z (GMT). No. of bitstreams: 1
Dissertacao_Sonia_Saeger_Meireles.pdf: 1109924 bytes, checksum: 6ffabb2bad0abb2a4fe90dc2b6845657 (MD5)
Previous issue date: 2006-10-02 / The objective of this study was to examine the validity and
reproducibility of the subjective evaluation used for tooth shade diagnosis. This study used the same ninety-two individuals selected for a randomized clinical trial comparing two carbamide peroxide bleaching agents. The shade of the six
upper anterior teeth of these subjects was determined before starting the clinical trial. One operator performed the objective shade determination of all upper anterior teeth (n= 552) using a spectrophotometer (Vita Easyshade, VITA). Then, two calibrated examiners subjectively determined the teeth shade
of the patients following their arrival time for the dental appointment. The visual (subjective) analysis was performed using a conventional shade guide (Vitapan Shade Guide, VITA). The reproducibility was evaluated using the kappa (k)
coefficient, considering the shades grouped in two categories (light and dark) or using the pondered kappa (Kw), which considers all the 16 shades of the guide.
The sensibility and specificity were determined using the spectrophotometer as the gold-standard. The faithful of the subjective evaluation for the two categories of shades was substantial (K= 0.69) and mild (Kw= 0.33) when considering all shades. The sensibility of the visual analysis was 86.9% and the specificity was 81.9%. The visual analysis of the shades was considered a valid method, despite the subjectivity, showing good reproducibility to differentiate
light and dark shades / Objetivou-se determinar a validade e reprodutibilidade da análise subjetiva no diagnóstico da cor dentária. Noventa e dois indivíduos, participantes de um ensaio clínico randomizado comparando duas concentrações do peróxido de carbamida utilizadas no clareamento vital caseiro, tiveram a cor dos seus seis dentes ântero-superiores avaliada antes do início do tratamento. Um operador analisou objetivamente a cor de todos os elementos dentais (n= 552) através de espectrofotômetro digital (Vita Easyshade, VITA). Em seguida, os pacientes foram examinados separadamente por dois examinadores calibrados, de acordo com a ordem de chegada para o atendimento, a fim de realizar a aferição visual da cor (Escala Vitapan, VITA). A reprodutibilidade foi avaliada pelo coeficiente kappa simples (k), considerando-se o agrupamento das cores em duas categorias (claras e escuras) ou pelo kappa ponderado (Kw), quando consideradas as dezesseis cores da escala. Os valores de sensibilidade e especificidade foram calculados utilizando-se o espectrofotômetro como padrão-ouro. A confiabilidade expressa pela análise subjetiva em função das duas categorias de cor foi substancial (K= 0,69). Quando se consideraram todas as cores, a confiabilidade foi razoável (Kw= 0,33). A sensibilidade da análise visual foi de 86,9% e a especificidade 81,9%. A avaliação visual da cor dentária mostrou-se como método válido, apesar de sua subjetividade, apresentando uma boa reprodutibilidade para o diagnóstico de colorações claras e escuras
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The Influence of Agroforestry on Soil Fertility in Coffee Cultivations : A Review and a Field Study on Smallholding Coffee Farms in ColombiaEkqvist, Ida January 2015 (has links)
Coffee is, together with cacao, the crop most commonly cultivated under shade trees in order to cope with physiological stress (as drought and sun radiation) and erosion as well as to generate additional income for the farmer. However, today this agroforestry coffee management is increasingly transformed into industrial plantation with little or no shade using varieties that tolerates full sun and can be planted with higher density. This conversion most often brings an intensified use of external input, such as fertilizers and pesticide, and a reduction in biodiversity as well as long term soil fertility. The objective of this study was to examine whether the inclusions of trees in coffee cultivations favour soil fertility and how it affects the output of the system. The aspect of output was not only delimited to the weight of coffee yield but take a broader perspective that comprises the farmer’s economy. This was done by conducting a review of previous research on the subject combined with a field study performed at six smallholding coffee farms with different levels of shade in Colombia from November to December 2014. The results of the field study serve as a site specific example and are discussed in relation to previous findings. Soil samples was taken at the farms and analysed for organic matter, soil moisture, respiration rate and acidity. The hypothesis was that the inclusion of trees in coffee cultivations can enhance the long term soil fertility when compared to monoculture systems. And also that agroforestry coffee can bring an increased safety for the farmer in terms of income, when compared to monoculture coffee. No general conclusions could be drawn based on the results from the field study; however the results show that a change from agroforestry management to monoculture management in coffee cultivations in Colombia can have a significant negative effect on soil respiration rate. Furthermore the study highlights the importance of taking into account the specific characteristics of the location and the management of the investigated farm when making conclusions about the effects of agroforestry on soil fertility. It is also concluded that long term studies, extending over at least a year, is necessary to fully see the effects of the cultivation practice on soil fertility.
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Production of wild ginger (siphonochilus aethiopicus) under protection and indigenous knowledge of the plant from traditional healersManzini, Tryphine Zodwa 09 February 2006 (has links)
A questionnaire survey was conducted in five different villages in Mpumalanga Province. Hundred and fifty traditional healers were interviewed. The aim of the survey was to record and document indigenous knowledge held by the traditional healers on wild ginger and eight other popular plants used by them. The healing properties of wild ginger as perceived by traditional healers, ranged from healing coughs, colds, flu, hysteria, malaria and menstrual disorder, to protection against lightning. Majority (77%) said that there was no difference in medicinal value between cultivated and those grown in the wild. The majority of the traditional healers (72%) said they would appreciate proper training on how to domesticate these plants. Traditional healers do not have professional knowledge and skills to produce theses medicinal plants. Therefore training is crucial to impart these skills. The income category of traditional healers ranged from less than R200 to a maximum of R3000. Traditional healers received as few as 1 to 5 patients per day. The consultation cost ranged from R20 to more than R95. People who gathered plants for traditional healers ranged from 1 to 10 depending on the popularity of the traditional healer and the size of his/ her surgery. An experiment was carried out at Johannesburg Center for the disabled (JOCOD), Lenasia, South of Johannesburg, in a plastic tunnel and under a shade net. The objective of the experiment was to determine the effect of using a tunnel or a shade net on the yield of rhizome and to determine the effect of different harvesting periods on rhizome yield of wild ginger. The treatments were four in number, namely; two growing structures (tunnel and shade net) and two harvesting periods. On the effect of harvesting periods on yield, although there was no significant differences in the number of enlarged roots harvested between the first harvesting period and the second harvesting period, the number of roots tended to be higher during the first harvesting period compared to the second harvesting period. There was a significant difference in the number of rhizomes between the first and the second harvesting periods. On the effect of growth structure on yield of wild ginger, the number of enlarged roots was significantly higher from plants grown in a tunnel compared with those grown in a shade net. There was a significant difference in rhizome circumference between plants grown in a plastic tunnel and those grown in a shade net. There were interactions between the harvesting date and growth structure for fresh enlarged root mass. Fresh mass of enlarged roots of wild ginger was greater during the first harvesting date than during the second harvesting date for plants grown in a plastic tunnel. For small scale or resource poor farmers, herbalists and traditional healers who wish to grow wild ginger under protection, it is better to grow wild ginger in a plastic tunnel than under a shade net, probably because wild ginger performs well in warm conditions. The plastic tunnels have a tendency of maintaining warm temperatures during winter months. Early harvesting of wild ginger at the end of June 28/06 than harvesting in September. This could be because wild ginger grows rapidly throughout the summer season and in winter, the growth rate drops (dormant stage) making early winter the right time to harvest. / Dissertation (M Inst Agrar (Horticulture))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted
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Indigenous knowledge of fever tea (lippia javanica) and effect of shade netting on plant growth, oil yield and compound compositionMokoka, Noko Norah 09 February 2006 (has links)
An experiment was conducted to determine the effects of shade netting on growth, oil yield and compound composition of fever tea (Lippia javaica). The treatments were nine shade nets of different light intensities (100% bird net, 40% green, 10, 12 and 18% white and 30, 40, 55 and 70% black). The layout used was a completely randomized design. The parameters measured were shoot width, fresh shoot mass, the number of plants flowered, plant height and photosynthetically active radiation. Shade netting did not have any effect on the shoot width of L. javanica. Eighteen percent white net was best suited to produce fresh shoot mass, whereas 55% black net, 40% black net and 10% white net produced lower fresh shoot mass. More plants that flowered were obtained under 70% black net than those grown under 30% black net. The number of plants that flowered increased from 22 to 35 with an increase in shading density. The height of plants was not affected by shade netting at 49 DAT. However, at 59 and 67 DAT, the height of the plants was greater under low light intensities (40, 55, and 70% black nets) than that of high light intensity (30% black). Twelve percent white net had the greatest plant height at 102 DAT. Shade netting significantly affected the adsorption and utilization of photosynthetically active radiation (PAR) above, across and below the plants at 102 DAT. Hundred percent bird net had the greatest amount of light intercepted above, across and below the plants. The amount of light intercepted above, below and across the plants was lower for lower shading intensity (30% black) than that of higher shading intensities (40%, 55% and 70% black). To determine shade-netting effect on oil yield and compound composition, fresh leaves (± 200g) of L. javanica were sampled from each shade net for essential oil extraction by hydrodistillation. The oil yield ranged from 0.29% to 0.41%. The oil had a clear to yellowish brown colour. No significant differences were detected for oil yield amongst the shade nets. The chemical compound analysis was carried out by GC/MS. The chemical compounds identified in the essential oil were <font face="symbol">a</font>-pinene, sebinen, myrcene, 1.8 myrcene, ipsenone, ipsedienone, <font face="symbol">b</font>-caryophyllen and germacrene-D. L. javanica plants grown under 10% white net, resulted in significantly higher myrcene content (15.7%) as compared to plants grown in other shade nets. Shade netting did not have any effect on the composition of á-pinene, sebinene, 1.8 myrcene, ipsenone, ipsedienone, <font face="symbol">b</font>-caryophyllen and germacrene-D. For commercial usage of myrcene, white net (10%) would be best suited for L. javanica production. To obtain information about indigenous knowledge of L. javanica, a survey was carried out among street traders, traditional healers, hawkers and farmers in Gauteng. The age group was between 20 and 73. The majority of respondents, who were self employed, were traditional healers followed by farmers. Most (98%) of the respondents indicated that they collected L. javanica from the veld by cutting the plant, whereas other respondents uprooted the whole plant when harvesting. Amongst the different uses of L. javanica mentioned, treatment of colds and coughs through steaming was stated by most (47%) of the respondents. Most (88%) of the respondents felt that it was important to conserve the plant for future generations and also to prevent the plant from becoming extinct. Traditional healers knew the uses and other important aspects of L. javanica than the farmers. / Dissertation (M Inst Agrar (Agronomy))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted
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Technologie výroby plastového stínítka lampičky / Production technology of plastic lamp shadeČajan, Tomáš January 2016 (has links)
This master thesis deals with design of injection molding technology for plastic lamp shade made of polycarbonate labelled Lexan 925. The injection is performed into injection mold with hot runner system. Initially there is a general study related to plastic materials and injection molding technology. Further the study continues with technological solution of production of the lamp shade. The designed injection mold is two-plate, double cavity mold with two hot nozzles and is equipped with a thread-unscrewing machine. This thesis contains part of the documentation and item list of the injection mold, along with technical-economical evaluation of the developed solution.
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Color of Porcelain Veneer after Final Cementation in Comparison to Try-in Paste and Permanent Cement: An In Vitro StudyAldahlawi, Abdulelah 10 November 2015 (has links)
Objectives: To evaluate and compare the color of porcelain veneers with try-in paste in relation to porcelain veneers with permanent cement. Also, to evaluate and compare combinations of three different shades and thicknesses of porcelain veneers and three cement shades before and after final cementation. Additionally, to evaluate and compare the color of porcelain veneers with cured permanent cement before and after aging. Background: Porcelain veneers and ceramic restorations have become one of the most popular approaches in the anterior area due to their natural appearance and esthetics. However, more conservative approaches have led to thinner restorations with increased translucency. A potential drawback to these restorations is that any color change in the luting cement can become clinically visible, and possibly affect esthetic appearance. Methods: One hundred and eight specimens were cut from feldspathic porcelain blocs (Vitablocs Mark II for CEREC). Three different Vita 3D- Master 1M1, 2M2, and 3M1 shades were assessed. All specimens were 12 x 14 mm, with three different thicknesses of 0.3, 0.5, and 1.0 mm. Light-cured resin cement (Variolink Veneer, Ivoclar Vivadent) with three different shades was used. The specimen color alone, with the try-in paste, and with pre-cured and post-cured resin cement was measured using a spectrophotometer (Color Eye 7000A), which measures CIE-L*a*b* values. Specimens were subjected to 30,000 cycles of accelerated aging (Themo-cycling, Sarbi Dental Enterprises Inc.). Color measurement for all specimens was performed again and ∆E values between groups been calculated. Statistical analysis was performed using one-way and three-way ANOVA, with level of significant set at α=0.05, to assess differences between groups. This was followed by post hoc Tukey's tests. Results: Statistical analysis showed a significant difference between try-in paste and corresponding cured resin cement. Pre-cured and post-cured resin cement values showed a significant difference between cement shades. Moreover, statistically significant differences were found between post-cured cement and after 30,000 cycles of thermo-cycling. Conclusions: The final color of porcelain veneers was highly affected by the different shades of resin cement and by the thicknesses of the porcelain veneer. The use of higher ceramic thickness decreased the ∆E values when compared to thinner veneers. Also, color stability of ceramic veneer restorations luted with resin cement, was significantly influenced by the aging.
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Characterizing the Invasion of an Understory Grass Species (Oplismenus undulatifolius (Ard.) Roem. & Schult) in the Mid-Atlantic Region of the United StatesBowen, Anna Kate Miller 24 July 2020 (has links)
No description available.
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