Dissertations / Theses: 'Degree-days'

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Krupová, Tereza. "Deriváty na počasí jako alternativní nástroj řešení rizikovosti." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-72022.

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Thesis deals with weather derivatives and their position within other financial instruments. It is divided into five main parts. The aim of the first part is to describe the basic mechanism and hallmarks of derivatives as a part of financial market. Also a brief history of weather derivatives is charted. The second chapter is focused on risk and fundamental risk factors and approaches. The weather risk management is presented. The third part discuses weather risk as special kind of risk. This part analyzes the impact of weather on the economy. The differences between weather derivatives and insurance are highlighted. The fourth chapter presents the weather derivatives from the users' points of view; it describes weather derivatives' structure and usage, main underlying indices and also looks on the pricing issues. In the final part the current situation and the possible future evolution of weather derivatives is presented. This part also includes information about the main organizations dealing with either weather management or derivatives.

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Monthei, Derek Reed. "Entomotoxicological and Thermal Factors Affecting the Development of Forensically Important Flies." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/26366.

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Studies were conducted on the effects of alcohol and opioids on the development of forensically important flies. In addition different methods of degree-day calculations and development thresholds were used to determine the effects on PMI estimates. The first study determined the effects of ethanol on the development of Phormia regina in vitro. Ground pork loin was treated with a 1, 5, or 10% ethanol solution to give an equivalent Blood Alcohol Concentration (BAC) of 0.01, 0.04, and 0.8 % w/v. A significant difference in the time for second instarsâ to complete the stage was seen between the 1% treated and control. Significant differences were also found among pupal and adult weights between all treatments and the control. A significant difference was shown between growth curves of the 5% treated and control for third instar larvae using the Kolmogorov-Smirnov test. The ethanol content of Phormia regina in migrating third instar larvae that fed on treated meat was examined using headspace-gas chromatography (HSGC). All larvae had a content of 0.01% w/v, including the control. The effects of ante-mortem injection of oxycodone in pigs were examined with respect to insect succession patterns and the development rates of Phormia regina. Pigs were given a subcutaneous injection of oxycodone hydrochloride (3 mg/kg by weight) and antemortem blood samples were collected prior to and following drug injection. Shortly after death the carcasses were placed at an open field site and allowed to decompose in a field cage. Insect samples were collected from carcasses for seven days post-mortem and the collected data were used to develop occurrence matrices. The Simple Matching Coefficient showed that successional patterns were similar between treated and untreated animals. Loin and liver from the carcasses were used as rearing media for in vitro development studies of Phormia regina. Kolmogorov-Smirnov test showed that third instar P. regina maggots from treated loin tissue were significantly longer in length than maggots feeding on untreated loin tissue. A significant difference in time was found among larvae on loin for the time from eclosion to completion of the second instar. Significant differences were seen in the weight of adults reared on liver and loin. A chi-square for homogeneity showed that adults were biased towards males (2:1) from untreated loin tissue. A final study compared weather data sources, Accumulated Degree-Day (ADD) methods, and postmortem interval (PMI) estimations based on threshold and developmental data source. Four pigs were used for statistical comparisons. Pigs were taken to a test site and allowed to decompose in an experimental cage. Probes recorded ambient temperatures and body temperatures. Maggot sampling was completed every day for each pig. A three way factorial linear fit model was used to test for statistical differences. Significant differences were seen in the calculated ADD based on probe location and the development threshold used. The ADD calculated from local weather station locations: Kentland Farm, Moore Farm, and Blacksburg Airport were also compared. A significant difference in ADD was found in the main effects among locations (Airport 44.1 ADD, Kentland 37.5 ADD, Moore 48.6 ADD), as well as among the thresholds used (10,12.2, and 14Â°C). Different PMI estimations also resulted when using development data from different development studies on Phormia regina.
Ph. D.

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Myburgh, Jolandie. "Estimating the post-mortem interval using accumulated degree-days in a South African setting." Diss., University of Pretoria, 2010. http://hdl.handle.net/2263/25700.

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Providing a presumptive identification of badly decomposed or skeletonized remains is the responsibility of a forensic anthropologist. An important component of identification is the estimation of a post-mortem interval (PMI) for the deceased. This information can: provide a window period for death, reduce the number of potential victims, exclude possible assailants and substantiate witness testimony. Due to a large number of open and relatively desolate fields in South Africa, human remains are frequently discovered in an advanced stage of decomposition. The aim of this study was to evaluate the usability of the method of Megyesi and associates (2005) in which Total Body Score (TBS) and Accumulated Degree-Days (ADD) were retrospectively applied to estimate the post-mortem interval (PMI). To achieve this, a longitudinal examination of quantitative variables, TBS and ADD, was conducted over a period of 8 months. This period included both summer and winter seasons. Scatter plots between TBS and PMI, and TBS and ADD were used to illustrate patterns in decomposition. Patterns of decay differed in winter and summer, with winter exhibiting distinct inactivity. Using Loglinear Random-effects Maximum Likelihood Regression, the r2 values for ADD (0.6227) and PMI (0.5503) for combined seasons were less than r2 values for separated seasons (ADD 0.7652; PMI 0.7677). In contrast to other studies, seasonality influenced the ADD model and PMI. Linear regression formulae for ADD and PMI as well as 95% confidence interval charts for TBS for ADD were developed. These equations, along with data from a local weather station, can be used to estimate the PMI with relative accuracy. AFRIKAANS : Verskaffing van 'n vermoedelike identifikasie van erg ontbinde of skeletale oorskot is die verantwoordelikheid van ‘n forensiese antropoloog. ‘n Belangrike deel van identifikasie is die beraming van ‘n post-mortem interval (PMI) vir die oorledene. Hierdie inligting verskaf 'n venster tydperk van dood, verminder die aantal potensiële slagoffers, sluit moontlike aanvallers uit en ondersteun getuienis. As gevolg van 'n groot aantal relatief verlate en oop velde in Suid-Afrika, word menslike oorskot dikwels aangetref in ‘n gevorderde stadium van ontbinding. Die doel van hierdie studie was om die bruikbaarheid van die metode van Megyesi en medewerkers (2005) wat gebruik maak van Totale Liggaams Telling (TLT) en Opgehoopte Graad-Dae (OGD) om die postmortem interval (PMI) te skat, terugwerkend te evalueer. Hiervoor was 'n longitudinale studie van kwantitatiewe veranderlikes, TBS en ADD, oor ‘n tydperk van 8 maande gedoen. Hierdie tydperk sluit beide somer en winter in. Verspreidingsgrafieke tussen TBS en PMI, en TBS en ADD is gebruik om patrone in ontbinding te illustreer. Ontbindingspatrone het verskil tussen winter en somer met duidelike onaktiwiteit in die winter. Logliniêre Tweekansige-effek Maksimum Waarskynlikheid Regressie was gebruik om die r2 waardes van die gekombineerde en geskeide seisoene te bepaal. The r2 waardes vir die OGD (0.6227) en PMI (0.5503) vir gekombineer seisoene was minder as die r2 waardes vir seisoene apart (OGD 0.7652; PMI 0.7677). In teenstelling met ander studies, het seisoenaliteit die OGD model en PMI beinvloed. Lineêre regressie formules vir OGD en PMI sowel as 95% vertrouensinterval kaarte vir TLT vir OGD was saamgestel. Hierdie formules saam met data vanaf ‘n plaaslike weerstasie kan gebruik word om die PMI met relatiewe akkuraatheid te skat.
Dissertation (MSc)--University of Pretoria, 2010.
Anatomy
unrestricted

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Day, Antony R. "An investigation into the estimation and weather normalisation of energy consumption in buildings using degree-days." Thesis, London South Bank University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298021.

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Young, Kert R. "Plant Establishment and Soil Microenvironments in Utah Juniper Masticated Woodlands." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3318.

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Juniper (Juniperus spp.) encroachment into sagebrush (Artemisia spp.) and bunchgrass communities has reduced understory plant cover and allowed juniper trees to dominate millions of hectares of semiarid rangelands. Trees are mechanically masticated or shredded to decrease wildfire potential and increase desirable understory plant cover. When trees are masticated after a major increase in tree population density and associated decrease in perennial understory cover, there is a risk that invasive annual grasses will dominate because they are highly responsive to the increased resource availability that commonly follows removal of the main resource user. To determine if tree mastication increases resource availability and subsequently favors invasive annual or perennial grasses, we compared soil temperature, water, and nutrient microenvironmental conditions and seedling establishment and growth. We used the major rangeland weed, cheatgrass (Bromus tectorum L.), to represent invasive annual grasses and Anatone bluebunch wheatgrass (Pseudoroegneria spicata (Pursh) A. Löve), a natural accession of native bluebunch wheatgrass, to represent the perennial grasses of the sagebrush-bunchgrass plant community. These comparisons were made between and within paired-adjacent masticated and untreated areas at three locations in Utah dominated by Utah juniper (Juniperus osteosperma (Torr.) Little). Juniper tree mastication generally increased resource availability with masticated areas having greater soil temperature, soil water availability, and soil N supply rates than untreated areas. Prior to juniper tree mastication litter mounds were not found to be resource islands probably because juniper trees themselves were using subcanopy soil water and nutrients. After juniper tree mastication and elimination of these predominant resource users, litter mounds served as resource islands with greater soil water availability and N supply rates than bare interspaces during the critical time for seedling establishment in spring. Plant growth followed in line with greater resource availability after tree mastication with masticated areas having more productive although fewer invasive-annual and perennial grass seedlings than untreated areas. These results suggest that increases in resource availability and warmer spring temperatures associated with mastication will not necessarily favor invasive annual over perennial grass seedling establishment. Resilience of the sagebrush-bunchgrass community to return to dominance after juniper control will likely be greatly influenced by how much of the sagebrush-bunchgrass community remains following tree control and the intensity of propagule pressure by invasive species. If only invasive annuals remain when the trees are treated then invasive annuals would be expected to dominate the post-treatment plant community especially with their ability to establish inside litter mounds unless they were also controlled and perennial grasses planted at the time of treatment.

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Ishaq, Atif, René Pasternak, and Christine Wessollek. "Evaluation of crop development stages with TerraSAR-X backscatter signatures (2010-12) by using Growing Degree Days." SPIE, 2017. https://tud.qucosa.de/id/qucosa%3A34982.

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TerraSAR-X images have been tested for agricultural fields of corn and wheat. The main purpose was to evaluate the impact of daily temperatures in crop development to optimize climate induced factors on the plant growth anomalies. The results are completed by utilizing Geographic Information Science, e.g. tools of ArcMap 10.3.1 and databases of ground truth and meteorological information. Synthetic Aperture Radar (SAR) images from German Aerospace Center (DLR) are acquired and the field survey datasets are sampled, each per month for three years (2010-2012) but only for the crop seasons (April-October). Correlation between SAR images and farmland anomalies is investigated in accordance with daily heat accumulations and a comparison of the three years’ SAR backscatter signatures is explained for corn and wheat. Finding the influence of daily temperatures on crops and hence on the TerraSAR-X backscatter is developed by Growing Degree Days (GDD) which appears to be the most suitable parameter for this purpose. Observation of GDD permits that the coolest year was 2010, either rest of the years were warmer and GDD accumulated in 2011 was higher as compared to that of 2012 in the first half of the year, however 2012 had rather more heat accumulation in the second half of the year. SAR backscatter from farmland depicts the crop development stages which depend upon the time when satellite captures data during the crop season. It varies with different development stages of crop plants. Backscatter of each development stage changes as the roughness and the moisture content (dielectric property) of the plants changes and local temperature directly impacts crop growth and hence the development stages.

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Isler, Paulo Roberto [UNESP]. "Ferramentas matemáticas para modelagem da temperatura com aplicação em graus-dias para otimização da produção agrícola." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/90448.

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Made available in DSpace on 2014-06-11T19:24:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-05Bitstream added on 2014-06-13T19:31:24Z : No. of bitstreams: 1 isler_pr_me_botfca.pdf: 418245 bytes, checksum: 17cd225e9fb840990eb59cc92588bcb5 (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
O Brasil é um grande produtor agrícola. Os dados do Levantamento Sistemático da Produção Agrícola (LSPA), divulgados pelo Instituto Brasileiro de Geografia e Estatística (IBGE), mostram uma previsão de 158,7 milhões de toneladas para a safra brasileira em 2011, um volume 6% maior que o recorde de 149,7 milhões de toneladas colhidas em 2010. Nos últimos anos a produção tem crescido e a área apta para plantio ainda não foi totalmente utilizada e estima-se que está sendo usada metade da área adequada para a agricultura. Esta grande produção se deve, em grande parte, ao clima do país, pois apesar das variações atuais de temperatura, o Brasil ainda possui um clima adequado para o cultivo de um grande número de espécies. Outro fator que tem sido relevante para o crescimento da agricultura é a evolução na forma de produção, pois a utilização de tecnologia de ponta e de novas variedades tem participação fundamental no desenvolvimento agrário. Mas, as grandes dimensões do país, a rapidez no desenvolvimento e as intensas modificações climáticas, têm trazido grandes problemas técnicos, econômicos e administrativos. Assim, os gestores deste setor têm buscado o auxílio de técnicas matemáticas e computacionais na obtenção de estimativas e nas tomadas de decisões. A modelagem matemática pode ser utilizada como ferramenta para auxiliar a melhoria na precisão e conseqüentemente na rentabilidade agrícola. Este trabalho propõe o uso de técnicas para modelagem matemática da temperatura diária, visando determinar equações matemáticas que descrevam as temperaturas diárias de um modo satisfatório, de tal forma que as curvas descritas pelas equações, auxiliem no cálculo de Graus Dia, que é uma importante medida na área de produção agrícola. Uma aplicação deste procedimento é feito para a cultura da cana de açúcar
Brazil is a large agricultural producer. The data in the Systematic Survey of Agricultural Production (LSPA), released by the Brazilian Institute of Geography and Statistics (IBGE), show a forecast of 158.7 million tonnes for the brazilian harvest in 2011, a volume 6% higher than the record of 149.7 million tons harvested in 2010. In recent years the production has grown and the area suitable for planting has not yet been fully used and it is estimated that is being used half the area suitable for agriculture. This large production is, in large part, to the climate of the country, because in spite of the variations of current temperature, Brazil still has a suitable climate for the cultivation of a large number of species. Another factor that has been important for the growth of agriculture is the evolution in the form of production, because the use of high technology and new varieties are also fundamental in agricultural development. But, the big dimensions of the country, the speed in the development and the intense climate changes, has brought a great many technical problems, economic and administrative. Thus, the managers of this sector has sought the aid of mathematical techniques and computational to obtain estimates and in making decisions. The mathematical modeling can be used as a tool to help the improvement in accuracy and consequently in agricultural profitability. This paper proposes the use of techniques for mathematical modeling of daily temperatures, in order to determine how mathematical equations to describe the daily temperatures in a satisfactory manner, so that the curves as described by the equations, help in the calculation of Degree-Day, which is a significant extent in the area of agricultural production. An application of this procedure is done for the culture of sugar cane

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Covert, Melanie M. "The Influence of Chilling and Heat Accumulation on Bloom Timing, Bloom Length and Crop Yield in Almonds (Prunus dulcis (Mill.))." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/667.

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Almonds are one of the first commercial nut trees to bloom in early spring and thus are susceptible to temperature patterns prior to and during bloom which affect bloom timing, bloom length, pollination and nut set. Data used in this project include yearly dates of 90% bloom from 1996-2006, bloom length in days and final crop yields in pounds per tree for Nonpareil and Mission varieties. Data were collected from the University of California Cooperative Extension reports on the 1993-2006 Regional Almond Variety Trials in Butte, San Joaquin and Kern Counties. Temperature pattern models in the form of Chill Hours (Chill Hour Model), Chill Units (Chill Unit Model), Chill Portions (Chill Portion Model) and Growing Degree Hours (GDH°) (Heat Model) prior to bloom were used to predict the date of 90% bloom for each variety, site and year. Temperature model results were compared to averaged actual dates of 90% bloom by site and variety used to predict bloom timing (Calendar Model). The relationship between bloom length in days and GDH° during bloom and the relationship between bloom length, GDH° during bloom and final crop yields were also evaluated. The average error in predicting the 90% bloom date for both Nonpareil and Mission was smaller using the Calendar Model compared to the four temperature pattern models. The Chill Portion model did not have significantly higher average error in predicting the date of 90% bloom than the Calendar model in Nonpareil. The Chill Unit and Chill Portion models had smaller errors in predicting 90% bloom date than the Chill Hour or GDH° model in Mission. GDH° during bloom was positively correlated with bloom length. GDH° during the first four days of Nonpareil bloom was significantly correlated with crop yields, with each additional GDH° during bloom correlated with a 0.4 lbs./tree increase in crop yield. Further research is needed on specific temperature thresholds and their relationship to physiological changes during almond bloom and pollination. The practice of monitoring chilling and heat accumulation will allow growers to anticipate bloom, prepare to optimize bee activity during bloom, and plan for possible crop yield variations due to adverse weather conditions during bloom in almonds.

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Isler, Paulo Roberto 1985. "Ferramentas matemáticas para modelagem da temperatura com aplicação em graus-dias para otimização da produção agrícola /." Botucatu, 2011. http://hdl.handle.net/11449/90448.

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Orientador: Helenice de Oliveira Florentino Silva
Banca: Dinival Martins
Banca: Vanderlei Marcos do Nascimento
Resumo: O Brasil é um grande produtor agrícola. Os dados do Levantamento Sistemático da Produção Agrícola (LSPA), divulgados pelo Instituto Brasileiro de Geografia e Estatística (IBGE), mostram uma previsão de 158,7 milhões de toneladas para a safra brasileira em 2011, um volume 6% maior que o recorde de 149,7 milhões de toneladas colhidas em 2010. Nos últimos anos a produção tem crescido e a área apta para plantio ainda não foi totalmente utilizada e estima-se que está sendo usada metade da área adequada para a agricultura. Esta grande produção se deve, em grande parte, ao clima do país, pois apesar das variações atuais de temperatura, o Brasil ainda possui um clima adequado para o cultivo de um grande número de espécies. Outro fator que tem sido relevante para o crescimento da agricultura é a evolução na forma de produção, pois a utilização de tecnologia de ponta e de novas variedades tem participação fundamental no desenvolvimento agrário. Mas, as grandes dimensões do país, a rapidez no desenvolvimento e as intensas modificações climáticas, têm trazido grandes problemas técnicos, econômicos e administrativos. Assim, os gestores deste setor têm buscado o auxílio de técnicas matemáticas e computacionais na obtenção de estimativas e nas tomadas de decisões. A modelagem matemática pode ser utilizada como ferramenta para auxiliar a melhoria na precisão e conseqüentemente na rentabilidade agrícola. Este trabalho propõe o uso de técnicas para modelagem matemática da temperatura diária, visando determinar equações matemáticas que descrevam as temperaturas diárias de um modo satisfatório, de tal forma que as curvas descritas pelas equações, auxiliem no cálculo de Graus Dia, que é uma importante medida na área de produção agrícola. Uma aplicação deste procedimento é feito para a cultura da cana de açúcar
Abstract: Brazil is a large agricultural producer. The data in the Systematic Survey of Agricultural Production (LSPA), released by the Brazilian Institute of Geography and Statistics (IBGE), show a forecast of 158.7 million tonnes for the brazilian harvest in 2011, a volume 6% higher than the record of 149.7 million tons harvested in 2010. In recent years the production has grown and the area suitable for planting has not yet been fully used and it is estimated that is being used half the area suitable for agriculture. This large production is, in large part, to the climate of the country, because in spite of the variations of current temperature, Brazil still has a suitable climate for the cultivation of a large number of species. Another factor that has been important for the growth of agriculture is the evolution in the form of production, because the use of high technology and new varieties are also fundamental in agricultural development. But, the big dimensions of the country, the speed in the development and the intense climate changes, has brought a great many technical problems, economic and administrative. Thus, the managers of this sector has sought the aid of mathematical techniques and computational to obtain estimates and in making decisions. The mathematical modeling can be used as a tool to help the improvement in accuracy and consequently in agricultural profitability. This paper proposes the use of techniques for mathematical modeling of daily temperatures, in order to determine how mathematical equations to describe the daily temperatures in a satisfactory manner, so that the curves as described by the equations, help in the calculation of Degree-Day, which is a significant extent in the area of agricultural production. An application of this procedure is done for the culture of sugar cane
Mestre

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Kotze, Maria Johanna. "Evaluating sex pheromone monitoring as a tool in the integrated management of vine mealybug, Planococcus ficus (signoret) (Homoptera: Pseudococcidae) / M.J. Kotze." Thesis, North-West University, 2006. http://hdl.handle.net/10394/1203.

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The vine mealybug, Planococcus ficus (Signoret) (Homoptera: Pseudococcidae) is a pest with significant economic impact on the grape growing industry in South Africa and other parts of the world. With the isolation and synthesizing of the vine mealybug sex pheromone in 2001, new control options for the integrated management of the vine mealybug have been created. The status of sex pheromone monitoring as a tool in the integrated management of the vine mealybug has been evaluated from different perspectives. A significant quantitative difference in male vine mealybug trap catch numbers has been observed between wine and table grape vineyards and results indicated that there were differences in the susceptibility of grape cultivars to vine mealybug. Currently, the delta trap design is the accepted trap design for vine mealybug monitoring. No studies have yet been conducted to determine the optimum trap parameters like size or design. Population pressure may have an influence on the qualitative efficiency of various trap designs. The basis for degree-day forecasting models has been established adequately. However, refinements need to be done and the incorporation of factors such as humidity and regionality also need to be considered. Daily maximum temperatures fluctuating around the upper developmental threshold temperature for prolonged periods of time seemed to suppress population numbers. Different vineyard management practices exist for wine and table grape production. While an action threshold of 65 vine mealybug males per trap per two-week period seems an acceptable threshold for table grape production, it may not be appropriate for wine grape (or raisin grape) production. Using sex pheromone traps for population monitoring is a valid technique in the arsenal of management tactics against the vine mealybug. However, refinements and validation of research results must be done further to build credibility into the monitoring system.
Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2006.

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Neto, Lourival Carmo Monaco. "Desenvolvimento de videira `Niagara Rosada´ podada em diferentes épocas." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-01112012-112415/.

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A cultura da videira \'Niagara Rosada\' apresenta grande importância em diferentes regiões produtoras, principalmente no estado de São Paulo. Para a produção dessa uva é fundamental a utilização da técnica cultural da poda, que pode ocorrer em diferentes épocas. Dessa forma o presente estudo teve como objetivo comparar o desenvolvimento da videira \'Niagara Rosada\' podada em diferentes épocas mediante a análise de características como o comprimento dos ramos, velocidade média de crescimento de ramos, duração em dias de cada período do ciclo produtivo e soma térmica em graus-dia (GD). As épocas de poda adotadas foram de inverno, com realização em 04/08/2010 e de verão, com realização em 28/01/2011. O delineamento estatístico utilizado foi o de blocos ao acaso com 7 e 8 unidades experimentais cada, totalizando 30 unidades. Cada bloco foi uma planta e a unidade experimental foi um ramo. Para a análise de médias foi empregado o teste de Tukey para comparar os tratamentos de poda de inverno e poda de verão. As variáveis foram comparadas em relação aos períodos do ciclo produtivos: poda à colheita, brotação à colheita, poda à brotação, brotação ao florescimento, florescimento ao início da maturação dos frutos e início da maturação dos frutos à colheita. Houve resultado significativo em todas as comparações entre os tratamentos, de forma que se confirmou que em relação ao tamanho dos ramos, a poda de inverno apresentou ramos mais compridos do que a poda de verão. Em relação à velocidade média de crescimento dos ramos, esta foi superior na poda de inverno do que o observado na poda de verão. Já na duração do ciclo produtivo, houve maior duração no início do ciclo na poda de inverno e maior duração no final do ciclo na poda de verão, de forma que no ciclo como um todo a duração foi praticamente a mesma. Finalmente para a soma térmica, a poda de inverno apresentou valores superiores em todo o ciclo, excetuando-se o período do florescimento ao início da maturação dos frutos, em que a poda de verão apresentou valores superiores.
The importance of the \'Niagara Rosada\" crop is major in several regions, especially in the state of São Paulo. In the production of this vine tree the use of pruning is essential, which can occur in several seasons. With that in mind, this study has as objective to compare \'Niagara Rosada\' vine tree\'s development under different pruning seasons by analyzing characteristics as the length of the branch, average branch growth velocity, duration in days of the production cycle and degreedays (DD). The adopted pruning seasons were the winter pruning, being done in 08/04/2010, and the summer pruning, being done 01/28/2011. As experimental plot were use 4 plants, with 7 or 8 branches each, with the total of 30 branches. To analyze the results was used the Tukey test, comparing the treatments in the different periods of the production cycle (Pruning to Harvest, Sprout to Harvest, Pruning to Sprout, Sprout to Flowering, Flowering to Early Ripening and Early Ripening to Harvest. There was a significant difference between the treatments in all the comparisons. For the length of the branches, the winter pruning showed bigger branches in all the periods than the length of the summer pruning. As for the average branch velocity, it was superior in all the periods in the winter pruning. When considering the duration in days of the periods of the production cycle there was, in the beginning, a longer duration in the winter pruning an a longer duration in the end of the cycle for the summer pruning. When considering the total duration both treatments presented almost the same number. Finally, for the degree-days, the winter pruning showed a bigger rate in all the cycle, except in the Flowering to Early Ripening period, in which the summer pruning showed a bigger rate.

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Kuhn, William Robert. "Pest management of billbugs in orchardgrass grown in Virginia." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/76916.

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The bluegrass billbug (Sphenophorus parvulus Gyllenhal) and hunting billbug (Sphenophorus venatus vestitus Chittenden) have become important pests of orchardgrass (Dactylis glomerata L.) grown in Virginia, causing 40 - 100% stand losses according to a 2005 survey of over 324 ha (800 ac) of orchardgrass. Their sheltered feeding habits combined with a lack of labeled insecticides for orchardgrass make billbug control extremely difficult for this crop. Over two seasons, orchardgrass fields were surveyed for paired feeding holes caused by feeding of the billbug spring adult. Simultaneously, barrier pitfall traps, a standard method for determining the presence of billbugs in orchardgrass, were used to trap billbug adults in the fields. A comparison of these methods using a Wilcoxon sign-ranked test found no significant differences in the time when paired feeding holes were first observed in fields and when billbug adults were first trapped, showing that the methods are equally satisfactory for determining the presence of billbugs in orchardgrass. In addition, temperature data from SkyBit E-Weather® service, which are currently used to alert growers and other interested parties of pertinent billbug activity in orchardgrass, was compared to data from a field-based weather data logger over the two seasons. A comparison of these data showed high coefficients of correlation, indicating a close relationship between these two degree-day collection methods. Therefore, the SkyBit system can continue to be used for the alert system. A field-border application of Metarhizium anisopliae (Metschnikoff) Sorokin strain F52 (Met-52), an entomopathogenic fungus, was evaluated against billbug adults as they enter orchardgrass fields in the spring. Randomized pairs of treated and untreated plots were placed along the edge of an orchardgrass field in studies over two seasons. Plots were monitored for billbug adults using barrier pitfall traps, and billbug adults were checked for Met-52 infection. The Met-52 proved unsatisfactory for controlling billbugs in this study. A field efficacy trial was used to evaluate several insecticides and Met-52 against billbug adults in orchardgrass over two seasons. A randomized complete block design, four insecticide treatments and an untreated control were used in each of two trials. Samples from each treatment plot were dissected and checked for billbug life stages and for injury to orchardgrass plants. In one trial, plants in the Sevin XLR Plus® treatment were found to have a significantly higher percentage of injury to the crowns than all other treatments except Mustang Max. No other significant differences were seen in this study.
Master of Science in Life Sciences

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13

Brown, Paul W. "Heat Units." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2013. http://hdl.handle.net/10150/299154.

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Bianconi, André [UNESP]. "Descrição da resposta germinativa de cultivares de Phaseolus vulgaris L. (Fabaceae) à temperatura e ao potencial osmótico." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/87883.

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A germinação de sementes representa uma etapa crítica para a sobrevivência da maioria das fanerógamas. Composição de gases, temperatura e água são os principais fatores ambientais limitantes do processo de germinação. Entre esses, a temperatura e a água exibem maior grau de flutuação, tanto em escala temporal como espacial, no ambiente terrestre, funcionando como importantes sinalizadores ambientais para a semente. Os objetivos deste trabalho foram fornecer a caracterização básica dos padrões germinativos de quatro cultivares (Carioca comum, Iapar 81, IPR Graúna e IPR Uirapuru) de Phaseolus vulgaris L. (Fabaceae); determinar as faixas ótimas de germinação para cada cultivar (experimentos em gradiente térmico com água destilada); realizar experimentos com interação dos fatores temperatura e potencial osmótico com soluções de polietilenoglicol 6000, visando à aplicação de modelos matemáticos baseados nos conceitos de graus-dia, psi-dia e na combinação destes dois conceitos (modelo psi-graus-dia), para se efetuar a comparação da resposta germinativa de tais cultivares. A cultivar IPR Graúna apresentou a faixa ótima com maior variação de distintas temperaturas (nove temperaturas), baseando-se na velocidade média de germinação; contrastando com a Iapar 81, que não apresentou uma faixa ótima, mas sim um único ponto ótimo (32,6ºC). Nenhuma das quatro cultivares apresentou germinação acima de 38,2ºC nem abaixo de 10,3ºC nos experimentos em gradiente térmico (água destilada). As temperaturas base obtidas pelo modelo de graus-dia variaram de 8,4 a 9,2ºC. Os ajustes (todos os R2s ≥ 0,70) ao modelo psi-graus-dia foram adequados para todas as cultivares, tanto na faixa supraótima quanto na infraótima. Assim sendo, ainda que mais estudos sejam necessários para melhorar a qualidade dos ajustes obtidos em relação...
Seed germination constitutes a crucial phase in relation to the life cycle of plant species. The composition of gases, temperature and water availability are the main environmental factors that may hinder several germination processes. Temperature and water availability, for example, are able to fluctuate considerably and may act as environmental “status’ indicators to the seeds. The present work was aimed at furnishing a basic characterisation of the germination patterns of four Phaseolus vulgaris cultivars, viz. “Carioca comum’, “Iapar 81”, “IPR Graúna” and IPR Uirapuru; assessing the optimum range of germination for each cultivar; conducting experiments in which the effects of temperature and osmotic potential were simultaneously analysed in order to deploy mathematical models concerning the concept of degree-days (thermal time) with the aim of comparing the germination response of such cultivars. “IPR Graúna’ exhibited a wider optimum range of temperature (nine distinct values) and “Iapar 81” presented only one temperature value as the optimum temperature (32.6ºC). The four cultivars did not germinate at temperatures higher than 38.2ºC and lower than 10.3ºC. The base temperatures derived from the application of the thermal time models varied from 8.4 to 9.2ºC. Regarding the hydrothermal-time model, the quality of the data fitting were deemed to be adequate (R2s ≥ 0.70) both in the suboptimum range and in the supra-optimum range. Other researches should be conducted in order to corroborate the present findings; nonetheless, the common bean cultivars were able to be compared and contrasted and exhibited, on the whole, a relatively homogenous... (Complete abstract click electronic access below)

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15

Koenig, John L. "TIMING OF FUNGICIDE APPLICATIONS FOR THE MANAGEMENT OF DOLLAR SPOT." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1253625623.

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16

Cline, Nathan Lyle. "Wet-Thermal Time and Plant Available Water in the Seedbeds and Root Zones Across the Sagebrush Steppe Ecosystem of the Great Basin." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4384.

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Following wildfires, plant materials are direct-seeded to limit erosion and annual weed invasion. Seedlings often fail to establish because selected plant materials are not always well adapted to local soil moisture and temperature conditions. In an effort to help improve plant materials selection and to evaluate sites potential revegetation, we have worked toward developing methodology to predict germination and root growth based on site specific soil moisture and temperature conditions. First, we characterized the seedbed environment of 24 sagebrush (Artemisia spp.) steppe sites throughout the Intermountain West to determine the wet-thermal time of five temperature ranges relevant to germination response and thermal-time model accuracy (Chapter 1). Second, we predicted potential germination for 31 plant materials at those same sites (Chapter 2). Third, in preparation to predict root growth at multiple sites, we characterized the drying patterns and the associated plant-available water for in the seedling root zone across nine woodland (Juniperus spp. and Piñus spp.) sites (Chapter 3). For all of these studies, we determined the effects of tree reduction and tree infilling phase at time of tree reduction. Our key findings are that seedbeds generally sum most wet-thermal time at temperature ranges where the germination rates fit thermal accumulation models quite well (R2 ≥ 0.7). The majority of plant materials summed enough wet-thermal time for a potential germination at most sites during the fall, early spring, and late spring. Soil drying primarily occurs from the soil surface downward. Drying rates and Plant available water associated with the first drying event increased with increasing soil depth. Root zone (1-30 cm) plant-available water increased before and decreased after the first spring drying event with increasing soil depth. Tree removal with increasing pretreatment tree infilling phase generally added progress toward germination, plant available water, and wet-thermal time in the seedbed and root zones of the sagebrush steppe in the Great Basin. Because soil moisture and temperature does not appear to be limiting for potential germination, combining germination and root growth models to create a more comprehensive model may allow for a more robust prediction for seedling survival. For either root growth or combined germination and root growth models, plant available water and wet-thermal time before the first spring drying period hold the most potential for successfully predicting seedling survival.

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Docema, Matheus Luís. "Fixação de frutos de caqui, sua relação com o acúmulo de graus-dia e a aplicação de ácido giberélico." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-10082016-144051/.

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A produção de caqui no estado de São Paulo vem aumentando, sendo o seu cultivo uma boa alternativa para a diversificação de plantas frutíferas pelos produtores. O conhecimento sobre a fenologia e fixação de frutos das principais cultivares de caquizeiros em clima subtropical é de grande importância para o desenvolvimento de práticas culturais que visam uma boa produção, uma vez que em clima temperado a produção é instável pelas altas quedas fisiológicas de flores e frutos. Para isso avaliou-se o acúmulo de graus-dia em diferentes fases fenológicas das principais cultivares plantadas em São Paulo, em clima Cwa, e o efeito da aplicação de ácido giberélico na fixação dos frutos. Para atingir o ponto de colheita, a cultivar Fuyu necessita, após a poda, um acúmulo de 3650 graus-dia, Giombo e Rama-Forte 4559 graus-dia e Taubaté 4280 graus-dia. A queda fisiológica de frutos das quatro cultivares ocorre em até três meses após a antese, com o acúmulo médio de 2074 graus-dia. No período de queda fisiológica, para as quatro cultivares, há dois picos acentuados de abscisão de frutos, o primeiro após a queda de pétalas, com 298 graus-dia e o segundo 50 dias após a antese, com 913 graus-dia. A aplicação exógena de ácido giberélico incrementa a fixação de frutos de caqui nas cultivares Fuyu, Giombo, Rama-Forte e Taubaté, quando há ensacamento de flores. Para as cultivares Fuyu, Giombo e Rama-Forte a aplicação de 100 mg L-1 de ácido giberélico na florada, aumenta a fixação dos frutos em mais de 20%. Para a cultivar Taubaté a aplicação de 300 mg L-1 de ácido giberélico incrementa a fixação em mais de 30%.
The production of persimmon in the Brazilian state of São Paulo is increasing, as its cultivation is a good alternative for the diversification of fruit plants for farmers. The knowledge about the phenology and fruit set of the main persimmon cultivars in subtropical climates is of great importance to the development of agricultural practices aiming for a good production, as in temperate climates the production is instable due to the large physiological flower and fruit drop. Therefore, the accumulation of degree-days in different phenological phases of the main cultivars planted in São Paulo state, in a Cwa climate, was evaluated, as well as the effect of applying gibberellic acid on the fruit set. To reach the point of harvest, the cultivar Fuyu requires 3650 degree-days after pruning, Giombo and Rama-Forte 4559 degree-days and Taubaté 4280 degree-days. The phenological fruit drop of the four cultivars occurs up to three months after the anthesis, with a mean of 2074 degree-days. In the period of physiological fruit drop of the four cultivars, there are two accentuated peaks of fruit abscission, the first after the drop of petals, with 298 degree-days and the second 50 days after the anthesis, with 913 degree-days. The exogenous application of gibberellic acid increases the fruit set of the persimmons for the cultivars Fuyu, Giombo, Rama-Forte and Taubaté, with flowers being bagged. For the cultivars Fuyu, Giombo and Rama-Forte the application of 100 mg L-1 of gibberellic acid during blooming, increases the fruit set by more than 20%. For the cultivar Taubaté the application of 300 mg L-1 of gibberellic acid increases the fruit set by more than 30%.

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Bianconi, André. "Descrição da resposta germinativa de cultivares de Phaseolus vulgaris L. (Fabaceae) à temperatura e ao potencial osmótico /." Rio Claro : [s.n.], 2009. http://hdl.handle.net/11449/87883.

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Orientador: Victor José Mendes Cardoso
Banca: Fábio Socolowski
Banca: Gustavo Habermann
Resumo: A germinação de sementes representa uma etapa crítica para a sobrevivência da maioria das fanerógamas. Composição de gases, temperatura e água são os principais fatores ambientais limitantes do processo de germinação. Entre esses, a temperatura e a água exibem maior grau de flutuação, tanto em escala temporal como espacial, no ambiente terrestre, funcionando como importantes sinalizadores ambientais para a semente. Os objetivos deste trabalho foram fornecer a caracterização básica dos padrões germinativos de quatro cultivares (Carioca comum, Iapar 81, IPR Graúna e IPR Uirapuru) de Phaseolus vulgaris L. (Fabaceae); determinar as faixas ótimas de germinação para cada cultivar (experimentos em gradiente térmico com água destilada); realizar experimentos com interação dos fatores temperatura e potencial osmótico com soluções de polietilenoglicol 6000, visando à aplicação de modelos matemáticos baseados nos conceitos de graus-dia, psi-dia e na combinação destes dois conceitos (modelo psi-graus-dia), para se efetuar a comparação da resposta germinativa de tais cultivares. A cultivar IPR Graúna apresentou a faixa ótima com maior variação de distintas temperaturas (nove temperaturas), baseando-se na velocidade média de germinação; contrastando com a Iapar 81, que não apresentou uma faixa ótima, mas sim um único ponto ótimo (32,6ºC). Nenhuma das quatro cultivares apresentou germinação acima de 38,2ºC nem abaixo de 10,3ºC nos experimentos em gradiente térmico (água destilada). As temperaturas base obtidas pelo modelo de graus-dia variaram de 8,4 a 9,2ºC. Os ajustes (todos os R2s ≥ 0,70) ao modelo psi-graus-dia foram adequados para todas as cultivares, tanto na faixa supraótima quanto na infraótima. Assim sendo, ainda que mais estudos sejam necessários para melhorar a qualidade dos ajustes obtidos em relação... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Seed germination constitutes a crucial phase in relation to the life cycle of plant species. The composition of gases, temperature and water availability are the main environmental factors that may hinder several germination processes. Temperature and water availability, for example, are able to fluctuate considerably and may act as environmental "status' indicators to the seeds. The present work was aimed at furnishing a basic characterisation of the germination patterns of four Phaseolus vulgaris cultivars, viz. "Carioca comum', "Iapar 81", "IPR Graúna" and IPR Uirapuru; assessing the optimum range of germination for each cultivar; conducting experiments in which the effects of temperature and osmotic potential were simultaneously analysed in order to deploy mathematical models concerning the concept of degree-days (thermal time) with the aim of comparing the germination response of such cultivars. "IPR Graúna' exhibited a wider optimum range of temperature (nine distinct values) and "Iapar 81" presented only one temperature value as the optimum temperature (32.6ºC). The four cultivars did not germinate at temperatures higher than 38.2ºC and lower than 10.3ºC. The base temperatures derived from the application of the thermal time models varied from 8.4 to 9.2ºC. Regarding the hydrothermal-time model, the quality of the data fitting were deemed to be adequate (R2s ≥ 0.70) both in the suboptimum range and in the supra-optimum range. Other researches should be conducted in order to corroborate the present findings; nonetheless, the common bean cultivars were able to be compared and contrasted and exhibited, on the whole, a relatively homogenous... (Complete abstract click electronic access below)
Mestre

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Philips, Christopher Robin. "Food webs and phenology models: evaluating the efficacy of ecologically based insect pest management in different agroecosystems." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/51813.

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Integrated pest management (IPM) is defined as an effective and environmentally sensitive approach to pest management that relies on a combination of common-sense practices. Integrated pest management programs use current, comprehensive information on the life cycles of pests and their interactions with host plants and the environment. This information, in combination with available pest control methods, is used to manage pest populations by the most economical means, and with the least possible hazard to people, property, and the environment. True IPM takes advantage of all appropriate pest management options including, as appropriate, the judicious use of pesticides. It is currently estimated the IPM in its full capacity is being practiced on less than ten percent of the agricultural land in the U.S. The primary objective of this research was to evaluate land management decisions and create new tools to promote a true IPM approach and encourage growers to reevaluate their method of insect control. To accomplish this I developed new predictive tools to reduce or eliminate unnecessary insecticide application intended to target cereal leaf beetle in wheat, and assessed a conservation biological control technique, farmscaping, to determine its true impact on lepidopteran pest suppression in collards.
Ph. D.

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20

Lucena, Eliseu MarlÃnio Pereira de. "Desenvolvimento e maturidade fisiolÃgica de manga âtommy atkinsâ no vale do SÃo Francisco." Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1399.

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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
O presente trabalho objetivou caracterizar as alteraÃÃes fÃsicas, fÃsico-quÃmicas, quÃmicas e bioquÃmicas durante o crescimento dos frutos de mangueira (Mangifera indica), cv. Tommy Atkins, da antese atÃ a colheita comercial, visando Ã definiÃÃo do ponto de colheita ideal em unidades de calor. Os frutos foram colhidos aos 35, 49, 63, 70, 77, 84, 91, 98, 105 e 112 dias apÃs a antese (DAA), sendo feitas as seguintes determinaÃÃes: aspectos morfolÃgicos externos; diÃmetros longitudinal, ventral e transversal; produto dos diÃmetros; massas fresca, seca e de Ãgua; teor de Ãgua; escalas de coloraÃÃo da casca, de Blush para coloraÃÃo da casca e de coloraÃÃo da polpa; luminosidade, croma e Ãngulo Hue da polpa; firmeza; unidades de calor (UC); sÃlidos solÃveis totais (SST); acidez total titulÃvel (ATT); pH; relaÃÃo SST/ATT; amido; aÃÃcares solÃveis totais, redutores e nÃo redutores; nitrogÃnio total, nÃo protÃico e protÃico; proteÃnas bruta e verdadeira; vitamina C; clorofila e carotenÃides totais; fenÃlicos polimÃricos, oligomÃricos e dimÃricos; pectinas total, solÃvel, de alta metoxilaÃÃo e de baixa metoxilaÃÃo; protopectina; percentagem de solubilizaÃÃo de pectina; atividade das enzimas pectinametilesterase, poligalacturonase, polifenoloxidase, peroxidase, amilase total, α- e β-amilases, α- e β-galactosidases extraÃdas de citosol e de parede celular; proteÃnas extraÃdas de citosol e de parede celular. O trabalho indicou que as mangas âTommy Atkinsâ atingiram a maturidade fisiolÃgica aos 98 DAA, que equivale a 1.685,09 UC. O croma da polpa foi o melhor indicador do estÃdio de desenvolvimento do fruto da mangueira cultivada sob irrigaÃÃo no sub-mÃdio SÃo Francisco, considerando-se o seu alto coeficiente de determinaÃÃo, R2=0,9832 (P < 0,01) e seu alto coeficiente de correlaÃÃo com pH, aÃÃcares solÃveis totais e carotenÃides totais, R=0,95; 0,93; e 0,93, respectivamente (P < 0,01).
The objective of this work was to characterize the physical, physicochemical, chemical and biochemical changes during the development of mango (Mangifera indica), cv. Tommy Atkins from anthesis to harvest, identifying the optimum harvest maturity stage in heat units. The fruits were harvested at 35, 49, 63, 70, 77, 84, 91, 98, 105 and 112 days after the anthesis (DAA), being made the following determinations: fruit external morphology; longitudinal, ventral e transverse diameters; product of the diameters; fresh and dry mass; water content and percentage; skin, Blush skin and pulp color scales; pulp luminosity, Hue angle and chroma; firmness; heat units (HU); total soluble solids (TSS); total titratable acidity (TTA); pH; TSS/TTA ratio; starch; total, reducing and nonreducing soluble sugars; total, protein and nonprotein nitrogen; crude and true protein; C vitamin; total chlorophyll and carotenoids; polymeric, oligomeric and dimeric phenolics; pectin total, soluble and high/low metoxilation degree; protopectin; solubilization pectin percentage; pectin metyhylesterase, poligalacturonase, polyphenol oxidase, peroxidase, total amylase, α- and β-amylases, α- and β-galactosidases enzymes activities; cell wall and cytosol proteins. This work has indicated that mango âTommy Atkinsâ reached the physiological maturity at 98 DAA, that is equivalent to 1.685,09 HU. The pulp chroma was the best fruit development stage indicator in the cultivated conditions of this study (SÃo Francisco valley), taking into account the high coefficient of determination, R2=0,9832 (P < 0,01) and excellent correlation coefficients with pH, total soluble sugars and total carotenoids, R=0,95; 0,93; e 0,93, respectively (P < 0,01).

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Morais, Katiule Pereira. "Desempenho agronomico de cana-de-açucar em Jaguari - RS." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/5067.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Currently the state of Rio Grande do Sul (RS) the cultivation of sugar cane is being encouraged for bioenergy. However, there is a lack of information on the performance of agricultural and industrial modern genotypes at conditions of RS. In order to evaluate the growth, development and quality of genotypes of sugar cane cultivation of sugarcane plant (2009/2010) and cane ratoon first year (2010/2011) an experiment was conducted in the municipality of Jaguari Central Depression of RS. The experimental design was randomized blocks with three replications. We evaluated 12 genotypes of 13 early and medium maturity / delayed a total of 25 materials, all of RIDESA. The evaluations were phyllochron, final leaf number on main stem height, leaf area, straw yield and agronomic and qualitative parameters. The phyllochron values between genotypes showed little variation, but the genotypes RB966229, RB947625 and RB008347 significant difference in relation to the cane plant and ratoon cane. The NFT showed no difference between the early-maturing genotypes, only cycle between the mid / late, and some genotypes of mid / late show higher NFT in sugarcane ratoon. The height growth was comprised of three distinct phases for all genotypes, starting with a slow growth after the phase of higher growth and finally there was a decrease in growth due to the start of the maturation process. The leaf area showed a growth pattern similar to the stem, but the last stage corresponded to a decrease in AF. The average yield of stalks of more productive genotypes in early-maturing crops of sugar cane plant and ratoon cane (96.6 and 123.4 TCH) was similar to that obtained with the most productive genotypes cycle mid / late (101.5 TCH and 128.0), with higher productivity in the cultivation of sugarcane ratoon. The genotype RB965911 RB925345 and early-maturing genotypes and RB925268, RB975019 RB987935 cycle and medium / late show qualitative variables, maturation rate and productivity of stem indicate that these genotypes as a high potential for the central region of the RS.
Atualmente no estado do Rio Grande do Sul (RS) o cultivo da cana-de-açúcar está sendo incentivado para fins bioenergéticos. No entanto, existe a carência de informações sobre o desempenho agrícola e industrial de genótipos modernos nas condições edafoclimáticas do RS. Com o objetivo de avaliar o crescimento, desenvolvimento e qualidade de genótipos de cana-de-açúcar em cultivo de cana-planta (2009⁄2010) e de cana-soca de primeiro ano (2010⁄2011) foi realizado um experimento no município de Jaguari, Depressão Central do RS. O delineamento experimental foi o blocos ao acaso com três repetições. Foram avaliados 12 genótipos de ciclo precoce e 13 de ciclo médio⁄tardio, totalizando 25 materiais, todos da RIDESA. As avaliações realizadas foram filocrono, número final de folhas na haste principal, estatura, área foliar, produção de colmos e parâmetros agronômicos e qualitativos. Os valores de filocrono entre os genótipos tiveram uma pequena variação, porém os genótipos RB966229, RB947625 e RB008347 apresentaram diferença significativa em relação à canaplanta e cana-soca. O NFT não apresentou diferença entre os genótipos de ciclo precoce, somente entre os de ciclo médio⁄tardio, sendo que alguns genótipos de ciclo médio⁄tardio apresentam maior NFT em cana-soca. O crescimento em estatura compreendeu três fases distintas para todos os genótipos, iniciando-se por um crescimento lento, após a fase de maior crescimento e por fim ocorreu uma diminuição do crescimento em função do inicio do processo de maturação. A área foliar apresentou um padrão de crescimento similar ao do colmo, porém a última etapa correspondeu ao decréscimo da AF. A produtividade média de colmos dos genótipos mais produtivos de ciclo precoce nos cultivos de cana-planta e canasoca (96,6 e 123,4 TCH) foi semelhante aquela obtida com os genótipos mais produtivos de ciclo médio/tardio (101,5 e 128,0 TCH), com maior produtividade no cultivo de cana-soca. O genótipo RB965911 e RB925345 de ciclo precoce e os genótipos RB925268, RB975019 e RB987935 de ciclo médio/tardio apresentam variáveis qualitativas, índice de maturação e produtividade de colmos que indicam esses genótipos como sendo os de maior potencial para a região central do RS.

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Pehrs, Malin, and Lina Hjort. "Energiutvärdering av Undervisningshuset på Kungliga Tekniska Högskolan i Stockholm : Uppföljning av energianvändning medelst normalårskorrigering." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-281917.

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Bostad- och servicesektorn står för cirka 40 % av den totala årliga energianvändningen i Sverige. För nybyggda hus med ambitiösa miljökrav, såsom objektet för denna studie, är en viktig del i hållbarhetsarbetet uppföljning och feedback av energianvändningen för att illustrera sambandet mellan ambition och faktiskt resultat. Energiuppföljning i Undervisningshuset, en byggnad på KTH Campus med ambitiösa visioner om hållbarhet och pedagogik, är därför syftet med denna studie. För att jämföra energianvändningen mellan olika år måste energianvändningen normaliseras vilket sker i två steg; korrigering för normalt brukande och normalårskorrigering. I denna rapport beräknas Undervisningshusets normaliserade energianvändning medelst energisignatur och graddagar, vilken jämförs med den enligt Energideklarationen förväntade energianvändningen som normaliserats med SMHI:s energi-index. Undervisningshusets energiprestanda är enligt energisignaturmetoden 56 kWh/m2 och år och enligt graddagsmetoden 59 kWh/m2 och år, jämfört med den förväntade energiprestandan i Energideklarationen på 60 kWh/m2 och år. Både resultaten för denna rapport och Energideklarationen klassificerar därmed Undervisningshuset med Energiklass B.
The housing- and service sector makes up about 40 % of the total yearly energy use in Sweden. For new buildings with ambitious requirements, such as the object of this study, an important part of the work towards sustainability is follow-up and feedback on its energy use to illustrate the connection between ambition and actual result. Energy follow-up for Undervisningshuset, a building on KTH Campus with ambitious visions of sustainability and pedagogy, is therefore the aim of this study. To compare the energy use in buildings between different years the energy use must be normalized which is done in two steps; correction for normal occupancy and standard year correction. In this report the normalized energy use of Undervisningshuset is calculated by means of energy signature and degree-days, which is compared to the expected energy use according to the Energy Declaration normalized by SMHI’s energy-index. The energy performance of Undervisningshuset is 56 kWh/m2 and year according to the energy signature method and 59 kWh/m2 according to the degree-day method, compared to the expected energy performance in the Energy Declaration of 60 kWh/m2 and year. Both the results of this report and the Energy Declaration thereby classifies Undervisninshuset with Energy Class B.

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23

Irvine, Paul Michael. "Using a logistic phenology model with improved degree-day accumulators to forecast emergence of pest grasshoppers." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Mathematics and Computer Science, 2011, 2011. http://hdl.handle.net/10133/3105.

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Many organisms, especially animals like insects, which depend on the environment for body heat, have growth stages and life cycles that are highly dependent on temperature. To better understand and model how insect life history events progress, for example in the emergence and initial growth of the biogeographical research subjects, we must first understand he relationship between temperature, heat accumulation, and subsequent development. The measure of the integration of heat over time, usually referred to as degree-days, is a widely used science-based method of forecasting, that quantifies heat accumulation based on measured ambient temperature. Some popular methods for calculation of degreedays are the traditional sinusoidal method and the average method. The average method uses only the average of the daily maximum and minimum temperature, and has the advantage that it is very easy to use. However, this simplest method can underestimate the amount of degree-day accumulation that is occurring in the environment of interest, and thus has a greater potential to reduce the accuracy of forecasting insect pest emergence. The sinusoidal method was popularized by Allen (1976, [1]), and gives a better approximation to the actual accumulation of degree-days. Both of these degree-day accumulators are independent of typical heating and cooling patterns during a typical day cycle. To address possible non-symmetrical effect, it was deemed prudent to construct degree-day accumulators to take into account phenomena like sunrise, sunset, and solar noon. Consideration of these temporal factors eliminated the assumption that heating and cooling in a typical day during the growth season is symmetric. In some tested cases, these newer degree-day integrators are more accurate than the traditional sinusoidal method, and in all tested cases, these integrators are more accurate than the average method. After developing the newer degree-day accumulators, we chose to investigate use of a logistic phenology model similar to one used by Onsager and Kemp (1986, [54]) when studying grasshopper development. One reason for studying this model is that it has parameters that are important when considering pest management tactics, such as the required degree-day accumulations needed for insects in immature stages (instars) to be completed, as well as a parameter related to the variability of the grasshopper population. Onsager and Kemp used a nonlinear regression algorithm to find parameters for the model. I constructed a simplex algorithm and studied the effectiveness when searching for parameters for a multi-stage insect population model. While investigating the simplex algorithm, it was found that initial values of parameters for constructing the simplex played a crucial role in obtaining realistic and biologically meaningful parameters from the nonlinear regression. Also, while analyzing this downhill simplex method for finding parameters, it was found there is the potential for the simplex to get trapped in many local minima, and thus produce extraneous or incorrectly fitted parameter estimates, although Onsager and Kemp did not mention this problem. In tests of my methods of fitting, I used an example of daily weather data from Onefour, AB, with a development threshold of 12 ±C and a biofix day of April 1st, as an example. The method could be applied to larger, more extensive datasets that include grasshopper population data on numbers per stage, by date, linked to degree accumulations based on the non-symmetrical method, to determine whether it would offer significant improvement in forecasting accuracy of spring insect pest events, over the long term.
xii, 106 leaves ; 29 cm

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Green, Mike. "The days of our lives: deep acting, surface acting and actors' health : a thesis presented in partial fulfillment of the requirements for the degree of Master of Arts in Psychology at Massey University, Albany, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1068.

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Although emotional labour has been studied extensively among work populations such as doctors, detectives and adventure tourism guides, there has been no known research on the psychology of actors and acting within an emotional labour framework. This investigation had two purposes. The first was to extend what is currently known about two emotional labour strategies: surface acting, the regulation of observable expressions of emotions, and deep acting, the regulation of felt emotions, to include actual actors. The dependent variables used in this study were job and life satisfaction. The second purpose was to examine whether having a sense of community moderated the relationship between surface acting, deep acting and the dependent variables. Responses from 89 professional, amateur and community theatre actors were analysed. Pearson’s correlation coefficients showed a significant relationship between surface acting and the dependent variables. Hierarchical regression results showed a significant moderation effect for sense of community on the relationship between deep acting and life satisfaction. Implications, limitations, and directions for future research are discussed.

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Goldman, Jaime M. "Seasonal Aggregations of the Florida Manatee (Trichechus manatus latirostris) in the Port Everglades and Intracoastal Regions of Fort Lauderdale, Florida." NSUWorks, 2010. http://nsuworks.nova.edu/occ_stuetd/31.

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The Florida manatee (Trichechus manatus latirostris), a subspecies of the West Indian manatee, is one of the most endangered marine mammals in United States waters. The Florida manatee is the only manatee that ranges into subtropical and temperate regions. During the winter months manatees adopt a “refuging strategy” where they aggregate at warm-water sources immediately following decreases in the ambient water temperature to below 20° C (68° F) in order to avoid cold stress syndrome (CSS). During the winter manatees aggregate in warm water refuges, including natural warm water springs and the effluent discharges of power plants. The purpose of this study was to determine the number of manatees that aggregate and utilize the waters of the Florida Power and Light (FPL) Plant in Port Everglades (PPE), Florida, its effluent canal, and the surrounding Intracoastal Waterway during the winter months. This study documents the importance of Port Everglades as a wintering refuge for the Florida manatee. This study analyzed the inverse relationship between the number of manatees present at a warm water effluent and water temperature. In this study data were collected over five manatee winter seasons (between 15 November and 31 March) from 1999-2004, from both boat-based and land-based surveys monitoring the presence of manatees in the effluent canal from the FPL electricity generating facility in Port Everglades, FL and the Intracoastal Waterway. Findings indicated that there was an inverse relationship between the number of manatees present and water temperature, where more manatees were present in cooler months, and fewer in warmer months. This study also analyzed the parameters of Catch per Unit Effort (CPUE) as well as heating degree-days and their effect on and relationship to the number of manatees present. The higher the heating degree-days number, the more severe, or cold, winter this indicates. The year with the highest heating degree-days, 24.98, was the 2002-2003 season, which was also the season with the highest number of manatees observed, 393, and the highest CPUE, 10.62 manatees/day.

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26

Craft, Jordan Michael. "Factors governing zoysiagrass response to herbicides applied during spring green-up." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/102874.

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Zoysiagrass (Zoysia spp.) is utilized as a warm-season turfgrass because of its density, visual quality, stress tolerance, and reduced input requirements. Turf managers often exploit winter dormancy in warm-season turfgrass to apply nonselective herbicides such as glyphosate and glufosinate to control winter annual weeds. Although this weed control strategy is common in bermudagrass (Cynodon spp.), it has been less adopted in zoysiagrass due to unexplainable turf injury. Many university extension publications recommend against applying nonselective herbicides to dormant zoysiagrass despite promotional language found in a few peer-reviewed publications and product labels. Previous researchers have used vague terminology such as "applied to dormant zoysiagrass" or "applied prior to zoysiagrass green-up" to describe herbicide application timings. These ambiguous terms have led to confusion since zoysiagrass typically has subcanopy green leaves and stems throughout the winter dormancy period. No research has sought to explain why some turfgrass managers are observing zoysiagrass injury when the literature only offers evidence that these herbicides do not injure dormant zoysiagrass. We sought to explore various herbicides, prevailing temperatures surrounding application, heat unit based application timings, and spray penetration into zoysiagrass canopies as possible contributors to zoysiagrass injury. The results indicated that a wide range of herbicides may be safely used in dormant zoysiagrass. However, as zoysiagrass begins to produce more green leaves, herbicides such as metsulfuron, glyphosate, glufosinate, flumioxazin, and diquat become too injurious. Glufosinate was consistently more injurious regardless of application timing than glyphosate and other herbicides. When temperatures were 10 °C for 7 d following treatment, a delayed effect of glyphosate and glufosinate effect on digitally-assessed green cover loss was noted on zoysiagrass sprigs. In subsequent studies on turf plugs, a 14-d incubation period at 10 °C reduced glyphosate but not glufosinate effects on turf green color reduction. Glyphosate applied at 125, and 200 GDD5C can safely be applied to zoysiagrass while glufosinate applied at the same timings caused inconsistent and often unacceptable zoysiagrass injury in field studies conducted at Blacksburg, VA, Starkville, MS, and Virginia Beach, VA. Zoysiagrass green leaf density was described as a function of accumulated heat units consistently across years and locations but variably by turf mowing height. Turf normalized difference vegetative index was primarily governed by green turf cover but reduced by herbicide treatments, especially when applied at greater than 200 GDD5C. Substantial spray deposition occurred to subcanopy tissue regardless of nozzle type, pressure and height above the zoysiagrass canopy based on spectrophotometric assessment of a colorant admixture. However, increasing nozzle height above the turf canopy and avoiding air induction type nozzles significantly reduced the percentage of green tissue exposed at lower canopy levels. Absorption of radio-labeled glyphosate and glufosinate was up to four times greater when exposed to zoysiagrass stems compared to leaves. Glyphosate translocated more than glufosinate and both herbicides moved more readily from stem to leaf than from leaf to stem
Doctor of Philosophy
Zoysiagrass (Zoysia spp.) is utilized as a warm-season turfgrass because of its density, visual quality, stress tolerance, and reduced input requirements. Being that zoysiagrass is a warm-season turfgrass, it enters a dormancy period during the winter months. During this period, zoysiagrasses' active growth is halted, and leaves lose their green color and turn a golden-brown color. The winter dormancy period presents turfgrass managers with a unique opportunity to apply nonselective herbicides such as glyphosate and glufosinate to control a broad spectrum of winter annual weeds. Although this weed control strategy is common in bermudagrass (Cynodon spp.), it has been less adopted in zoysiagrass due to turfgrass managers observing unexplainable turfgrass injury. Many university extension publications recommend against applying nonselective herbicides to dormant zoysiagrass despite language found in peer-reviewed publications and product labels suggesting they could be safely applied. Previous researchers have used vague terminology such as "applied to dormant zoysiagrass" or "applied prior to zoysiagrass green-up" to describe herbicide application timings. These terms have led to confusion about when to make these applications since zoysiagrass typically has subcanopy green leaves and stems throughout the winter dormancy period. No research has sought to explain why some turfgrass managers observe zoysiagrass injury when the literature only offers evidence that these herbicides do not injure dormant zoysiagrass. Research projects were designed to explore various herbicides, temperatures surrounding herbicide applications, application timings, and spray penetration into zoysiagrass canopies as possible contributors to zoysiagrass injury. The results indicated that a wide range of herbicides may be safely used in dormant and semidormant zoysiagrass. However, as zoysiagrass begins to produce more green leaves and stems, herbicides such as metsulfuron, glyphosate, glufosinate, flumioxazin, and diquat become too injurious and should be avoided. Across multiple research studies, glufosinate was consistently more injurious regardless of application timing than glyphosate and other herbicides. When temperatures were 10 °C for 7-d following treatment, it delayed zoysaigrass response to glyphosate and glufosinate. In a subsequent study, when temperatures were at 10 °C for a 14-d period, glyphosate and the nontreated reached 50% green cover at the same time, which suggests cold temperatures could mitigate glyphosate injury on zoysiagrass over a 14-d period. The 10 ° temperature only delayed glufosinate injury on zoysiagrass, and no safening was observed. The results also indicated that as temperatures increased, glyphosate and glufosinate rate in which injury was observed increased on the zoysiagrass. Glyphosate applied at 125, and 200 GDD5C can safely be applied to zoysiagrass while glufosinate applied at the same timings caused inconsistent and often unacceptable zoysiagrass injury in field studies conducted at Blacksburg, VA, Starkville, MS, and Virginia Beach, VA. Zoysiagrass injury increased when glyphosate and glufosinate were applied later into the spring when more green leaves were present regardless of location. Accumulated heat units and zoysiagrass green leaf density were closely related, indicating that accumulated heat units could be a useful tool for turfgrass managers to track zoysiagrass spring green-up. Substantial spray deposition was found on subcanopy zoysiagrass leaves and stems regardless of nozzle type, pressure, and height above the zoysiagrass canopy based on recovered colorant at the upper, middle and lower levels of the zoysiagrass canopy. However, avoiding air induction-type nozzles and raising spray height may slightly decrease penetration of spray droplets into a zoysiagrass subcanopy, but a large percentage of droplets still reached the middle and lower canopy layers in this research. Absorption of radio-labeled glyphosate and glufosinate was up to four times greater when applied directly to zoysiagrass stolen compared to leaves. Glyphosate translocated more than glufosinate, and both herbicides moved more readily from stem to leaf than from leaf to stem. These data suggest limiting the number of green zoysiagrass leaves at application would be an effective method to avoid injury zoysiagrass when applying nonselective herbicides

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27

Stuart, Graeme. "Monitoring energy performance in local authority buildings." Thesis, De Montfort University, 2011. http://hdl.handle.net/2086/4964.

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Energy management has been an important function of organisations since the oil crisis of the mid 1970’s led to hugely increased costs of energy. Although the financial costs of energy are still important, the growing recognition of the environmental costs of fossil-fuel energy is becoming more important. Legislation is also a key driver. The UK has set an ambitious greenhouse gas (GHG) reduction target of 80% of 1990 levels by 2050 in response to a strong international commitment to reduce GHG emissions globally. This work is concerned with the management of energy consumption in buildings through the analysis of energy consumption data. Buildings are a key source of emissions with a wide range of energy-consuming equipment, such as photocopiers or refrigerators, boilers, air-conditioning plant and lighting, delivering services to the building occupants. Energy wastage can be identified through an understanding of consumption patterns and in particular, of changes in these patterns over time. Changes in consumption patterns may have any number of causes; a fault in heating controls; a boiler or lighting replacement scheme; or a change in working practice entirely unrelated to energy management. Standard data analysis techniques such as degree-day modelling and CUSUM provide a means to measure and monitor consumption patterns. These techniques were designed for use with monthly billing data. Modern energy metering systems automatically generate data at half-hourly or better resolution. Standard techniques are not designed to capture the detailed information contained in this comparatively high-resolution data. The introduction of automated metering also introduces the need for automated analysis. This work assumes that consumption patterns are generally consistent in the short-term but will inevitably change. A novel statistical method is developed which builds automated event detection into a novel consumption modelling algorithm. Understanding these changes to consumption patterns is critical to energy management. Leicester City Council has provided half-hourly data from over 300 buildings covering up to seven years of consumption (a total of nearly 50 million meter readings). Automatic event detection pinpoints and quantifies over 5,000 statistically significant events in the Leicester dataset. It is shown that the total impact of these events is a decrease in overall consumption. Viewing consumption patterns in this way allows for a new, event-oriented approach to energy management where large datasets are automatically and rapidly analysed to produce summary meta-data describing their salient features. These event-oriented meta-data can be used to navigate the raw data event by event and are highly complementary to strategic energy management.

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Mahé, Kélig. "Sources de variation de la forme des otolithes : Implications pour la discrimination des stocks de poissons Identifying blue whiting (Micromesistius poutassou) stock structure in the Northeast Atlantic by otolith shape analysis. Otolith shape as a valuable tool to evaluate the stock structure of swordfish Xiphias gladius in the Indian Ocean Directional bilateral asymmetry in otolith morphology may affect fish stock discrimination based on otolith shape analysis Do environmental conditions (temperature and food composition) affect otolith shape during fish early-juvenile phase? An experimental approach applied to European Seabass (Dicentrarchus labrax)." Thesis, Littoral, 2019. http://www.theses.fr/2019DUNK0539.

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L’évaluation et la gestion des populations de poissons se basent sur l'utilisation d’unités de gestion appelées « stocks halieutiques ». Pour discriminer ces stocks, la forme des otolithes, pièces calcifiées de l’oreille interne des poissons, peut être utilisée. Dans ce contexte, cette thèse s'est consacrée premièrement à l’étude de la variabilité spatio-temporelle de la forme des otolithes chez 3 espèces de poissons présentant des caractéristiques écologiques (taille, vitesse de nage, comportement dans la colonne d’eau, etc.) et des environnements biogéographiques différents. Les résultats montrent qu’il existe un gradient structurel décroissant de taille des stocks allant des espèces de grands pélagiques aux espèces démersales. Ceci est lié au fait que certaines espèces démersales comme la bogue (Boops boops) sont contraintes par la présence de barrières géographiques et de fronts hydrologiques ce qui n’est pas le cas chez les espèces pélagiques analysées (merlan bleu, Micromesistius poutassou ; Espadon, Xiphias gladius). Dans un deuxième temps, nous avons testé les effets de facteurs confondants potentiels (e.g. l’asymétrie bilatérale directionnelle, AD) sur le pouvoir discriminant de la forme des otolithes. Ainsi, nous avons montré qu'il existe chez la bogue une AD, induite par un processus de latéralisation et qui varie en amplitude et en direction selon la zone géographique étudiée. Chez la bogue, cette AD impacte les résultats d’identification des stocks par la forme qui changent en fonction de l'otolithe, droit ou gauche, utilisé. Si la forme de l’otolithe est utilisée pour discriminer les stocks halieutiques, c’est parce qu’elle reflète en particulier les conditions environnementales qu’a subi le poisson au cours de sa vie. Ainsi, dans la troisième partie de la thèse, nous avons analysé, en conditions contrôlées, les effets de la température et du taux d'acides gras polyinsaturés omega-3 (n-3 AGPI) contenus dans l’alimentation sur la morphogenèse des otolithes de bars (Dicentrachus labrax). Après la naissance, deux étapes peuvent être distinguées dans l’ontogenèse de la forme de l’otolithe avec en premier lieu un allongement qui traduit une croissance moins rapide de l’axe dorso-ventral par rapport à l’axe antéro-postérieur. Il s'en suit des modifications plus localisées avec en particulier une complexification de la zone comprise entre le rostre et l’anti-rostre a priori essentiellement liée au facteur thermique. A l’inverse, le taux de n-3 AGPI ne semble pas influencer la morphogenèse de l’otolithe. L’utilisation des degrés-jours de croissance (GDD) a permis de montrer que l’effet de la température est bien d’accélérer la morphogenèse, mais aussi de changer sa trajectoire: à valeur de GDD fixe, pour 2 températures données, les formes diffèrent. L’ensemble des résultats acquis lors de cette thèse valident l’utilisation de la forme des otolithes pour discriminer les stocks de poissons, mais souligne également le besoin de connaître précisément les sources de la variabilité morphologique des otolithes intra-stock pour pouvoir déterminer plus précisément les limites des stocks halieutiques
The assessment and management of fish populations is based on the use of management units called fish stocks. The shape of otoliths, calcified structures of the fish's inner ear, can be used to discriminate these stocks. First, this thesis focuses on the study of the spatio-temporal variability of the otolith’s shape for three fish species with different ecological characteristics (size, swimming speed, behaviour in the water column, etc.) and biogeographical environments. The results showed that there is a decreasing structural gradient across stock sizes from large pelagic species to more localised demersal species. This is linked to the fact that some demersal species such as the bogue (Boops boops) are constrained by the presence of geographical barriers and hydrological fronts, which is not the case for the analysed pelagic species (blue whiting, Micromesistius poutassou; swordfish, Xiphias gladius). Secondly, we tested the effects of potential confounding factors (e. g. bilateral directional asymmetry, DA) on the discriminating power of an otolith’s shape. We have shown that there is a DA for bogue, induced by the lateralisation process, which varies in amplitude and direction according to the geographical area. In the bogue, this DA impacts stock identification by otolith shape, which changes according to which otolith is used (i.e. right or left). Otolith shape is useful to discriminate among fish stocks because it reflects the specific environmental conditions that fish have experienced during their lifetime. Finally, in the third part of the thesis, we analyzed, under controlled conditions, the effects of temperature and the diet content of omega-3 polyunsaturated fatty acids (n-3 PUFAs) on otolith morphogenesis for seabass (Dicentrachus labrax). After emergence, two phases can be distinguished in the ontogenesis of otolith shape with an initial elongation that reflects slower growth of the dorso-ventral axis compared to the antero-posterior axis. This leads to more localized modifications, in particular, in a more complex area between the rostrum and the anti-rostrum, which is clearly linked to the thermal regime. Conversely, the percentage of n-3 PUFAs does not appear to influence otolith morphogenesis. The use of growing degree days (GDD) has shown that the effect of temperature is to accelerate morphogenesis, but also to change its trajectory: at a fixed GDD value, for two given temperatures, the shapes differ. All the results obtained in this thesis validate the use of the otolith shape to discriminate fish stocks, but also emphasize the need to know the precise sources of morphological variability of intra-stock otoliths in order to determine more precisely the limits of fish stocks

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Webber, J. D. "Phenology of hazelnut big bud mites in Canterbury and implications for management." Lincoln University, 2007. http://hdl.handle.net/10182/342.

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Eriophyoid big bud mites are key pests of hazelnuts throughout the world, although little is known of the identity and impact of the species on New Zealand hazelnut crops. The key objectives of this study were to determine the species of mite present on New Zealand crops, explore a method of monitoring mite emergence from overwintering big buds, determine the phenology of mites in relation to tree phenology and weather, and identify the optimum timing for control measures. The presence of both Phytoptus avellanae (Nalepa 1889) (Acari: Phytoptidae) and Cecidophyopsis vermiformis (Nalepa 1889) (Acari: Eriophyidae) was confirmed, the latter species being a new record for New Zealand. Preliminary diagnostic DNA sequences were determined for both species. A sticky band technique was developed to monitor mite emergence from overwintering big buds, and mite emergence was found to occur between early and late spring. Mite emergence and movement occurred when daily temperatures were greater than 15 degrees C and when mean temperatures were greater than 9 degrees C, with mite emergence increasing with temperature. It proved difficult to relate the phenology of hazelnut to mite emergence, however, the development of new buds during mite emergence was a crucial factor in the infestation of new buds. An accumulated heat sum model (DD), started at Julian date 152 and using a lower threshold temperature of 6 degrees C, predicted the onset of emergence on two cultivars and at two sites as occurring at approximately 172 DD. A regression model based on leaf number, bud height, bud width, DD and Julian date provided a more satisfactory prediction of percent accumulated mite emergence. It is recommended both peak mite emergence and the appearance of hazelnut buds should be used to optimise the time to apply control measures. Therefore, a control should be applied before buds measure 0.5 x 0.5 mm (width x height), are enclosed within the axil, and have a rounded tip, or, when 50% accumulated mite emergence has occurred, which ever occurs first. A preliminary field experiment tested the application of sulphur (40 g/10 litres of 800 g/kg No Fungus Super Sulphur) at 2, 50 and 80% accumulated mite emergence. The greatest reduction in mite numbers was achieved with an application at approximately 50% emergence. Considerable variation in mite emergence occurred between years, therefore optimum timing of controls would need to be determined by monitoring mites, new buds and weather conditions each year. Field collection of mites also identified the presence of Typhlodromus doreenae Schicha (Acari: Phytoseiidae) which would warrant further study for inclusion in an integrated mite control programme.

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Burns, Erik. "Pun recognition in L1 and L2 readers : Seven days without a pun makes one weak." Thesis, Stockholms universitet, Engelska institutionen, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-47153.

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Language play has an important position in the use of language. Cook (in Lucas, 2005) makes the argument that language play is even one of the primary uses of language. Partly due to the focus on research in second language learning, advanced L2 users’ language processing gets little attention in research on language use (Shaw & McMillion, 2008). Therefore, there is limited knowledge regarding the reading processes of this group. While Shaw and McMillion (2008) show that there is no difference in language proficiency between L1 and advanced L2 readers, Paradis (2009) argues that there indeed is a difference in processing among L1 and advanced L2 speakers. Gernsbacher and Robertson (1995) examined the differences in processing between more and less skilled L1 readers using ambiguous words and puns. However, this kind of research has not been done for L1 and advanced L2 readers. A study concerning the speed and ability in pun recognition was carried out to investigate whether any differences could be found between L1 and advanced L2 readers, with the same language proficiency. Tests in accuracy and speed in recognizing puns were carried out with university students in Stockholm and Los Angeles, while a survey investigating degree of amusement was distributed online. Initial hypotheses assumed that L1 readers, compared to L2 readers, would be both more skilled and faster at identifying a number of categories of puns as well as perceiving all categories of puns as being more amusing. Results show support for some of these hypotheses: L1 speakers were faster and more accurate in finding certain categories of puns. However, other categories showed no difference, and results were not able to prove differences in degree of amusement between the two groups. Questions about other categorizations of puns are raised, as well as further research opportunities.

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31

PILLAI, Vinoshene. "Intravital two photon clcium imaging of glioblastoma mouse models." Doctoral thesis, Scuola Normale Superiore, 2021. http://hdl.handle.net/11384/109211.

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32

Glatz, Juanita. "The effect of temperature on the development and reproduction of Busseola fusca (Lepidoptera: Noctuidae) / Juanita Glatz." Thesis, 2015. http://hdl.handle.net/10394/15246.

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Busseola fusca is an indigenous lepidopteran pest species in tropical Africa, attacking several grain crops. Crop loss caused by this pest can be as high as 100 % depending on conditions. Despite it being a major pest in Africa, occurring in contrasting climatic zones, only a few studies have been published on its developmental biology. The effect of temperature on the development of B. fusca was studied at five different temperature regimes namely 15, 18, 20, 26 and 30 ± 1 °C and 70 ± 30 % relative humidity (RH) with 14L: 10D photoperiod. The number of instars for B. fusca was also determined. The most favourable temperature as well as the upper threshold temperature for larval development was found to be between 26 and 30 °C. Total development period was 152.6 to 52.6 days, respectively, at 15 °C, and 26 - 30 °C. The thermal constants for B. fusca was 99.50, 536.48, 246.25 and 893.66 °D and lower temperature threshold was 10.36, 8.14, 8.99 and 8.84 °C, for completion of the egg, larval, pupal, and egg-to-adult stages, respectively. The number of larval instars was determined by using head capsule widths that ranged from 0.31 - 2.68 mm. Clear distinctions of head capsule widths could be made from instar 1 to 3, yet overlapping occurred from instar 4 to 6. No distinction could be made between instars 7 and 8 in terms of head capsule width. All successive instars, except for instar eight, increased in size according to Dyar’s ratio. The effect of temperature on reproduction of B. fusca was studied at 15, 20, 26 and 30 ± 1 °C, 70 ± 30 % RH with 14L: 10D photoperiod. Oviposition occurred at all the temperatures evaluated, but no fertility was recorded at 30 °C. The total number of eggs laid by B. fusca females was 300 - 400 eggs and the optimum temperature for oviposition and fertility was determined to be between 20 and 26 °C. Results from this study on the thermal constants and lower and upper threshold temperatures of B. fusca can be used to predict the impact of climate change on the distribution and population growth of this pest.
MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

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Véliz, Karina. "The impact of climate change on the U.S. power sector: price and quantity effects." Thesis, 2014. https://hdl.handle.net/2144/14091.

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In U.S. homes, 22 percent and 6 percent of the consumption of electricity is devoted to satisfy cooling and heating demands, respectively. A warming climate alters these consumption patterns by increasing the demand for cooling and reducing the demand for heating. This dissertation uses econometric techniques to examine the effect of climate change on the U.S. power industry through the study of the responsiveness of electricity demand to changes in temperature, and the impact of a climate-induced demand on electricity price and expenditures. In the second chapter a fixed-effects model and a cointegration model at the state level are used to investigate the determinants of residential, commercial and industrial electricity consumption for the 48 contiguous states. The results indicate substantial geographical heterogeneity in the response of demand to cooling and heating degree days, with the Midwest showing the greatest sensitivity. Residential consumers are impacted the most; on average, they experience a 13-18 percent increase in expenditures. In the third chapter the standard method of modeling electricity consumption is extended by the analysis of a wide range of set points above and below 65 F, and by including wet bulb temperatures. The statistical results for Massachusetts validate the use of 65 F for the residential sector, but demonstrate that a set point of 55 F and wet bulb temperature best characterizes the commercial sector. Using the models generated with these set points, climate change is projected to raise residential and commercial demand by 2.6 percent and 4 percent, respectively. In the fourth chapter, previous analyses on climate-induced expenditures are improved by accounting for the dual impact that climate change has on the electric power sector: an increase in both demand and price. A projected 2.6 C rise in temperature by 2070 in Massachusetts increases electricity prices by 11 to 18 percent. This increase in price, together with the increase in demand estimated in chapter three, translates into a 5.8 percent rise in expenditures for an average household. The results clearly demonstrate that climate-driven change in electricity price is the main determinant of the expected change in expenditures for electricity by households in the state.

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Chen, Dianlong. "The effect of heat on fruit size of day-neutral strawberries." Thesis, 2013. http://hdl.handle.net/10214/6579.

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The effect of temperature on fruit and achene characteristics of day-neutral strawberries were tested by two field experiments in Florida and Ontario, and one controlled-environment experiment. The results suggested that fruit became smaller as weather became hotter. This was mainly caused by ovule number and fruit volume/ovule which were determined before flowering. Fruit volume was determined by cell number and cell size. The cell number was determined before flowering, and after flowering there are a constant number of cell divisions. Cell volume plays a relatively minor role on fruit volume and cool temperature increased cell volume. Ovule number was determined 462 degree days before flowering and 14°C appeared to be the optimum temperature for ovule initiation. When there was a smaller proportion of developed achenes, the achenes appeared to be larger and have a similar contribution to fruit development than when there was a larger proportion. ‘Albion’ performed better in Florida, whereas ‘San Andreas’ performed better in Ontario.

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Tam, Andrew. "Permafrost in Canada's Subarctic Region of Northern Ontario." Thesis, 2009. http://hdl.handle.net/1807/18954.

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An investigation of permafrost (permanently frozen soil) was conducted in Canada’s subarctic region of Northern Ontario. Environmental baseline conditions and permafrost states were estimated using seasonal freezing and thawing energies based on observed climate data and the Stefan equation. Field studies provided measurements of the active layer depths and validated the permafrost states; laboratory studies of the soil samples provided characterization for organic materials that have high affinity for soil moisture. Palsas (unique dome-like formations) were observed to have enhanced permafrost cores beneath a thermal insulating organic layer. With climate change, results suggest the possibility of shifts from the classification of continuous to discontinuous permafrost states in areas lacking the presence of organic materials that can have environmental and ecological impacts. Northern infrastructures may become destabilized with the degradation of permafrost while palsas may become lone permafrost refuges for biodiversity that depend on cooler ecosystems, such as polar bears.

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Mushi, Clemence Sebastian. "The role of plant densities and growing degree days in the evaluation of high yielding corn (Zea mays L.) genotypes." 1986. http://hdl.handle.net/2097/22121.

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Hibbard, Emily L. "Effect of Spring And Winter Temperatures on Winter Moth (Geometridae: Lepidoptera) Larval Eclosion in New England." 2014. https://scholarworks.umass.edu/masters_theses_2/91.

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Field and laboratory experiments were conducted to elucidate various factors influencing the temperature-dependent larval eclosion of winter moth, Operophtera brumata L, in New England. We found no difference in duration of the embryonic stage of eggs reared from larvae collected in Massachusetts (MA) and on Vancouver Island, British Columbia (BC), where winter temperatures are rarely below freezing. The number of growing degree days (GDD) required for larval eclosion declined with the number of days chilled in the laboratory and number of days below freezing in the field, confirming the findings of previous studies. Thus, eggs hatched with fewer GDD, when the spring came later than usual. Date of oviposition had no effect on date of hatch. Eggs laid by naturally occurring (feral) females hatched sooner with lower GDD than eggs from laboratory-reared females from MA and BC held on the same trees over the winter. South-facing eggs on the stems of trees hatched on average 1.6 days sooner than north-facing eggs. Growing degree days calculated from bi-hourly measures of temperature were 15% greater than GDD estimates based on the average of daily maximum and minimum temperatures, as used by many GDD estimates made for online sources. Over two years, the mean GDD in ⁰C for hatch of feral eggs based on bihourly temperature measurements, a 1 Jan start date and a 3.9⁰C developmental threshold was 176.53 ± 6.35SE

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Quazi, K. Hassan. "A Framework for Modelling Species-Specific Site Quality Index Based on Data Generated From Remote Sensing Imagery and a Process-Based Model." Thesis, 2008. http://hdl.handle.net/1882/1033.

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This Thesis presents a framework for modelling species-specific site quality index (SQI) at a spatial resolution of 250 m by integrating biophysical variables of growing degree days (GDD), soil water content (SWC), and incident photosynthetically active radiation (PAR) in descriptions of potential tree growth. Development of GDD maps is based on processing and blending remotely-sensed data acquired with the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on the Terra satellite and ETM+ sensor on Landsat-7 satellite at spatial resolutions of 250 m and 28.5 m. Descriptions of SWC are based on a temperature-vegetation wetness index (TVWI) that relies on MODIS-based optical and thermal image products. PAR is estimated with an existing solar-radiation distribution model. SQI is defined as a function of species vital attributes and species environmental response to GDD, TVWI, and PAR. The methods are applied to a balsam fir [bF; Abies balsamea (L.) Mill.] dominated region in northwest New Brunswick. Comparisons between SQI and field-based estimates of site index and enhanced vegetation index showed that about 66 and 88% of the values corresponding to a series of Forest Development Survey lines (691 in total) were within 16% of SQI values. On average 92.1% of high bF-content stands (> 50% composition) in the area fell on medium-to-very high SQI values (> 0.50). Based on these agreements, SQI can be perceived as a good predictor of potential tree-species growth in the selection of optimal sites for biomass and wood fibre production.

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Gibson, Lara Dawn. "Characterization of Fruit Development and Ripening of Vaccinium angustifolium Ait. in Relation to Microclimate Conditions." 2011. http://hdl.handle.net/10222/14407.

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Berry ripening in lowbush blueberry (Vaccinium angustifolium Ait.) is influenced by developmental, physiological and climatic factors resulting in a heterogenous mix of maturities at harvest. This study characterizes the physico-chemical changes which occur during fruit ontogeny and links ripening patterns to micoclimate. Individual clones in five commercial fiels were followed in the 2006 and 2007 growing seasons. Phenolic acids, flavonols, and flavan-3-ols decreased and anthocyanins increased with maturity. Peak maturity consistently occurred at 1200 accumulated growing degree days (GDD). There was a sharp decline in fruit retention at the end of the growing season suggesting a date after which harvested yield declines but no consistent pattern was detected between years or fields.The consistency of GDD accumulation in relation to ripening pattern suggests GDDs can be used as a predictive ripening index. The physico-chemical nature of ripe berries indicates ripe berries could be harvested earlier than is currently the practice.

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Dissertations / Theses on the topic 'Degree-days'

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