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Avaliação horitcultural da laranjeira \'Folha Murcha\', tangerineira \'Satsuma\' e limeira ácida \'Tahiti\' sobre doze porta-enxertos / Horticultural evaluation of Folha Murcha sweet orange, Satsuma manadarin and Tahiti lime on twelve rootstocksCantuarias-Avilés, Tatiana Eugenia 10 August 2009 (has links)
A citricultura brasileira está fundamentada predominantemente sobre apenas um cultivar porta-enxerto, o limoeiro Cravo, e explora poucos cultivares copa, de uma maneira geral. Desse modo, o setor citrícola fica limitado na abertura de suas fronteiras de exportação para frutas frescas por estar baseado em um pequeno número de cultivares. Além disso, ao redor de 80% dos plantios estão reunidos em uma região compreendida por quase 600 mil ha, de forma concentrada, no Estado de São Paulo e sul do Triângulo Mineiro. Esses fatos também acarretam em grande vulnerabilidade fitossanitária, com ameaças crescentes de pragas e doenças, levando à redução da produtividade e ao acréscimo dos custos de implantação e condução dos pomares. A Clorose Variegada dos Citros (CVC) ou amarelinho, causada pela bactéria Xylella fastidiosa, é um exemplo destas ameaças. De elevada severidade em laranjas doces, causa redução no tamanho dos frutos, tornando-os inaptos para a comercialização in natura ou para produção de suco concentrado. Recentemente, as perdas em produção causadas pela CVC têm sido estimadas em até 10-14% da safra comercializável. Atualmente, o manejo da CVC está baseado na utilização de mudas sadias, poda de ramos afetados, e controle dos vetores. Além dessas medidas, é importante manter os tratos culturais exigidos no pomar. Entretanto, a utilização de cultivares resistentes é estratégia imprescindível para convivência com a doença em longo prazo. Este trabalho buscou avaliar o desempenho horticultural da laranjeira Folha Murcha, da tangerineira Satsuma cv. Okitsu e da limeira ácida Tahiti sobre doze porta-enxertos. Tangerina Satsuma cv. Okitsu e lima ácida Tahiti são espécies não sintomáticas em relação à CVC e tornam-se opções com potencial de exploração em pequenas propriedades. A laranjeira Folha Murcha tem demonstrado maior tolerância à CVC comparativamente aos demais cultivares de laranja doce. Os experimentos foram conduzidos na Estação Experimental de Citricultura de Bebedouro, EECB, (SP), e instalados em 2001. Em todos os experimentos foram avaliados o desenvolvimento vegetativo, produção e qualidade dos frutos (por no mínimo três safras) em cada combinação copa/porta-enxerto. Avaliações adicionais a respeito da tolerância à CVC foram realizadas no experimento de laranjeira Folha Murcha. Nos experimentos conduzidos sem irrigação, foi avaliada a tolerância ao déficit hídrico das copas usando duas metodologias: avaliação visual subjetiva e medição direta da coloração das folhas. Na limeira ácida Tahiti, a coloração externa dos frutos de exportação foi quantificada em função de variáveis colorimétricas, definindo-se uma metodologia quantitativa alternativa ao sistema atual de classificação dos frutos, baseado apenas na apreciação visual subjetiva. A avaliação horticultural de copas de laranjeira Folha Murcha, limeira ácida Tahiti e tangerineira Satsuma cv. Okitsu em doze porta-enxertos permitiu identificar porta-enxertos alternativos ao limoeiro Cravo, sendo estes os trifoliatas Flying Dragon, FCAV e Rubidoux. / Brazilian citriculture is mainly based on one rootstock cultivar, the Cravo Rangpur lime, exploring a restricted number of scion cultivars. This situation limits the expansion of citrus production for fresh fruit export, due to the limited number of cultivars in use. Besides, near 80% of citrus orchards are located in an area of approximately 600,000 ha, in the São Paulo State and the southern region of the Minas Gerais State. These facts also impose a large phytossanitary vulnerability to citrus production, due to the increasing threats of pests and diseases outbreaks, that cause productivity decrease and higher costs for orchard establishment and management. The Citrus Variegated Chlorosis (CVC), caused by the xylem-limited bacterium, Xylella fastidiosa, is one example of such threats. This disease is extremely severe in sweet oranges, causing size reduction ad quality deterioration of fruits, that become unsuitable for fresh consume or juice processing. The losses associated to CVC have been recently estimated in 10-14% of the total comercial crop in São Paulo State. CVC management is currently based on the use of healthy nursery plants, pruning of injured branches and control of the vectors. In addition to these strategies, it is important to maintain adequate cultural practices for orchard management. Nonetheless, the utilization of resistant cultivars is an indispensable strategy to co-exist with the disease in the long term. This study was aimed to evaluate the horticultural performance of Folha Murcha sweet orange, Okitsu Satsuma mandarin and Tahiti lime grafted onto twelve rootstocks. Okitsu Satsuma mandarin and Tahiti lime are assymptomatical species in relation to CVC, with potential to be produced in small areas. The Folha Murcha sweet orange has demonstrated high tolerance to CVC, when compared with other sweet orange cultivars. The trials were conducted at the Estação Experimental de Citricultura de Bebedouro, (EECB), and were planted in 2001. Evaluations of plant growth, yield and fruit quality were carried out in all the trials, during three years. In the Folha Murcha trial, additional evaluations of CVC tolerance were conducted. In the non-irrigated trials, tree water deficit tolerance was evaluated by two methods: visual assessment of water stress and direct leaf color measurements. In Tahiti lime, peel color of export fruits was measured and a quantitative methodology was defined as an alternative for current classification criteria, which are based on the subjective visual inspection of external fruit aspect. The horticultural evaluation of Folha Murcha sweet orange, Okitsu Satsuma mandarin and Tahiti lime onto twelve rootstocks allowed to identify the trifoliate rootstocks Flying Dragon, Rubidoux and FCAV as alternatives to Cravo Limeira.
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Produção, caracterização e avaliação ecônomica de destilados de batata doceWeber, Caroline Trevisan January 2017 (has links)
A batata-doce possui grande importância na alimentação humana e expressivo potencial para produção de etanol. A produção brasileira desta cultura é a 20ª no ranking mundial, com produção de 525.814 t em 2014, destacando-se o Rio Grande do Sul, responsável por 30,68% da produção do país. Shochu é a bebida alcoólica destilada mais consumida no Japão, produzida por destilação de fermentados de diversas fontes amiláceas, incluindo a batata-doce. Em sua fabricação é utilizado o koji, cultura sólida de fungos tradicional dos países asiáticos, mas que torna o processo produtivo lento e com alto risco de contaminação. Considerando a alta produtividade de batata-doce e a influência da cultura japonesa no Brasil, principalmente na culinária, percebe-se uma grande oportunidade de agregar valor a essa matéria-prima. Os objetivos deste trabalho são fazer o estudo de um processo alternativo - mais rápido e com menor risco de contaminação - para produção de destilado de batata-doce similar ao shochu, e a avaliação da viabilidade econômica para produção do mesmo. No processo alternativo proposto, o koji foi substituído pela enzima Stargen 002, mistura contendo alfa-amilase e glucoamilase, e utilizou-se uma pectinase para redução da viscosidade do meio. O tempo de processo reduziu de 14 dias para apenas 1 dia. As análises dos compostos de interesse foram realizadas por HPLC e GC. Quanto às matérias-primas, o teor de açúcares redutores totais foi maior na batata-doce de casca creme e polpa creme (30,42±1,54%), seguida pela batata-doce de casca púrpura e polpa creme (27,44±0,36%) e por último a batata-doce de casca rosada e polpa alaranjada (20,57±0,49%), e o teor de umidade seguiu a ordem inversa. Os resultados obtidos pelo processo padrão não foram satisfatórios em razão do baixo rendimento da fermentação alcoólica (40,59-42,51%) e da formação de compostos acima do limite da legislação, resultantes de fermentação acética. O rendimento experimental da fermentação alcoólica foi maior utilizando a levedura Angel Thermal Resistance Alcohol® (73,65%), seguida da Lalvin DV10® (70,39%) e por último a Lalvin EC1118® (67,31%), sendo maiores do que os obtidos com o uso das técnicas convencionais de produção de shochu, pois a não contaminação por bactérias acéticas no fermentado possibilitou maior rendimento em etanol. Por destilação em batelada, foram separadas frações de cabeça, coração e cauda, e em todas elas o componente álcool metílico mostrou-se acima dos limites da legislação. Realizou-se, então, experimento sem adição de pectinase, e o problema de formação de metanol foi eliminado. Entretanto, houve queda no rendimento da fermentação alcoólica (51,65-54,75%), indicando que a menor desintegração da batata-doce prejudica o andamento do processo fermentativo. Todos os compostos analisados mostraram-se dentro dos limites das normas vigentes. As frações cabeça e cauda foram descartadas e a fração coração foi diluída até teor alcoólico de 25% (v.v-1) e envasada. O destilado produzido, batizado de “Tchêchu”, e o shochu comercial apresentaram as mesmas bandas de adsorção em análise FTIR, identificando semelhança entre os mesmos. O custo de produção de uma garrafa (750 mL) de “Tchêchu” foi estimado em R$ 8,75. Com preço unitário de R$ 15,75 e utilizando-se a taxa SELIC (9,25% a.a.) como taxa mínima de atratividade, tem-se VPL de R$ 1.815.107,34, TIR de 26%, e payback descontado de 2,44 anos, o que mostra que a implantação de uma destilaria para produção de “Tchêchu” é economicamente viável. / Sweet potatoes have great importance in human food and have significant potential for ethanol production. The Brazilian production of this crop is the 20th in the world ranking, with production of 525,814 t in 2014, standing out Rio Grande do Sul, responsible for 30.68% of the country's production. Shochu is the most widely consumed spirit in Japan, produced by the distillation of fermented mash from a variety of starchy sources, including sweet potatoes. In its manufacture is used koji, a solid fungus culture traditional of the Asian countries, but that makes the productive process slow and at high risk of contamination. Considering the high productivity of sweet potatoes and the influence of Japanese culture in Brazil, a great opportunity to add value to this raw material is perceived. The objectives of this work are to study an alternative process - faster and with less risk of contamination - for the production of sweet potato distillate similar to shochu, and to study the economic viability analysis for its production. In the alternative process proposed, koji was replaced by the enzyme Stargen 002, a mixture containing alpha-amylase and glucoamylase, and a pectinase was used to reduce the viscosity of the medium. The process time reduced from 14 days to only 1 day. Analyzes of the compounds of interest were performed by HPLC and GC. Total reducing sugar content was higher in sweet potatoes with cream peel and cream pulp (30.42 ± 1.54%), followed by sweet potatoes with purple peel and cream pulp (27.44 ± 0.36%) and finally sweet potatoes with rose peel and orange pulp (20.57 ± 0.49%), and the moisture content followed the reverse order. The results obtained by the standard process were not satisfactory due to the low yield of alcoholic fermentation (40.59-42.51%) and the formation of compounds above the limit of the legislation, resulting from acetic fermentation. The experimental yield of alcoholic fermentation was higher using Angel Thermal Resistance Alcohol® (73.65%), followed by Lalvin DV10® (70.39%) and Lalvin EC1118® (67.31%), being higher than those obtained with the use of conventional methods of shochu production, since the non-contamination by acetic bacteria in the fermentation allowed a higher yield in ethanol. Fractions of head, heart and tail were separated by distillation, and in all of them the methyl alcohol component showed above the limits of the legislation. An experiment was performed without addition of pectinase, and the problem of methanol formation was eliminated. However, there was a decrease in the yield of alcoholic fermentation (51.65-54.75%), indicating that lower disintegration of sweet potatoes impairs the progress of the fermentation process. All compounds analyzed were within the limits of the current laws. Head and tail fractions were discarded and heart fraction was diluted up to 25% alcoholic strength (v.v-1) and bottled. The distillate produced, named "Tchêchu", and commercial shochu presented the same adsorption bands in FTIR analysis, identifying similarity between them. The cost of producing a bottle (750 mL) of "Tchêchu" was estimated at R $ 8.75. With a unit price of R$ 15.75 and using the SELIC rate (9.25%) as minimum acceptable rate of return there is a NPV of R$ 1,815,107.34, an IRR of 26%, and a discounted payback of 2.44 years, which shows that the implementation of a distillery to produce "Tchêchu" is economically viable.
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Avaliação horitcultural da laranjeira \'Folha Murcha\', tangerineira \'Satsuma\' e limeira ácida \'Tahiti\' sobre doze porta-enxertos / Horticultural evaluation of Folha Murcha sweet orange, Satsuma manadarin and Tahiti lime on twelve rootstocksTatiana Eugenia Cantuarias-Avilés 10 August 2009 (has links)
A citricultura brasileira está fundamentada predominantemente sobre apenas um cultivar porta-enxerto, o limoeiro Cravo, e explora poucos cultivares copa, de uma maneira geral. Desse modo, o setor citrícola fica limitado na abertura de suas fronteiras de exportação para frutas frescas por estar baseado em um pequeno número de cultivares. Além disso, ao redor de 80% dos plantios estão reunidos em uma região compreendida por quase 600 mil ha, de forma concentrada, no Estado de São Paulo e sul do Triângulo Mineiro. Esses fatos também acarretam em grande vulnerabilidade fitossanitária, com ameaças crescentes de pragas e doenças, levando à redução da produtividade e ao acréscimo dos custos de implantação e condução dos pomares. A Clorose Variegada dos Citros (CVC) ou amarelinho, causada pela bactéria Xylella fastidiosa, é um exemplo destas ameaças. De elevada severidade em laranjas doces, causa redução no tamanho dos frutos, tornando-os inaptos para a comercialização in natura ou para produção de suco concentrado. Recentemente, as perdas em produção causadas pela CVC têm sido estimadas em até 10-14% da safra comercializável. Atualmente, o manejo da CVC está baseado na utilização de mudas sadias, poda de ramos afetados, e controle dos vetores. Além dessas medidas, é importante manter os tratos culturais exigidos no pomar. Entretanto, a utilização de cultivares resistentes é estratégia imprescindível para convivência com a doença em longo prazo. Este trabalho buscou avaliar o desempenho horticultural da laranjeira Folha Murcha, da tangerineira Satsuma cv. Okitsu e da limeira ácida Tahiti sobre doze porta-enxertos. Tangerina Satsuma cv. Okitsu e lima ácida Tahiti são espécies não sintomáticas em relação à CVC e tornam-se opções com potencial de exploração em pequenas propriedades. A laranjeira Folha Murcha tem demonstrado maior tolerância à CVC comparativamente aos demais cultivares de laranja doce. Os experimentos foram conduzidos na Estação Experimental de Citricultura de Bebedouro, EECB, (SP), e instalados em 2001. Em todos os experimentos foram avaliados o desenvolvimento vegetativo, produção e qualidade dos frutos (por no mínimo três safras) em cada combinação copa/porta-enxerto. Avaliações adicionais a respeito da tolerância à CVC foram realizadas no experimento de laranjeira Folha Murcha. Nos experimentos conduzidos sem irrigação, foi avaliada a tolerância ao déficit hídrico das copas usando duas metodologias: avaliação visual subjetiva e medição direta da coloração das folhas. Na limeira ácida Tahiti, a coloração externa dos frutos de exportação foi quantificada em função de variáveis colorimétricas, definindo-se uma metodologia quantitativa alternativa ao sistema atual de classificação dos frutos, baseado apenas na apreciação visual subjetiva. A avaliação horticultural de copas de laranjeira Folha Murcha, limeira ácida Tahiti e tangerineira Satsuma cv. Okitsu em doze porta-enxertos permitiu identificar porta-enxertos alternativos ao limoeiro Cravo, sendo estes os trifoliatas Flying Dragon, FCAV e Rubidoux. / Brazilian citriculture is mainly based on one rootstock cultivar, the Cravo Rangpur lime, exploring a restricted number of scion cultivars. This situation limits the expansion of citrus production for fresh fruit export, due to the limited number of cultivars in use. Besides, near 80% of citrus orchards are located in an area of approximately 600,000 ha, in the São Paulo State and the southern region of the Minas Gerais State. These facts also impose a large phytossanitary vulnerability to citrus production, due to the increasing threats of pests and diseases outbreaks, that cause productivity decrease and higher costs for orchard establishment and management. The Citrus Variegated Chlorosis (CVC), caused by the xylem-limited bacterium, Xylella fastidiosa, is one example of such threats. This disease is extremely severe in sweet oranges, causing size reduction ad quality deterioration of fruits, that become unsuitable for fresh consume or juice processing. The losses associated to CVC have been recently estimated in 10-14% of the total comercial crop in São Paulo State. CVC management is currently based on the use of healthy nursery plants, pruning of injured branches and control of the vectors. In addition to these strategies, it is important to maintain adequate cultural practices for orchard management. Nonetheless, the utilization of resistant cultivars is an indispensable strategy to co-exist with the disease in the long term. This study was aimed to evaluate the horticultural performance of Folha Murcha sweet orange, Okitsu Satsuma mandarin and Tahiti lime grafted onto twelve rootstocks. Okitsu Satsuma mandarin and Tahiti lime are assymptomatical species in relation to CVC, with potential to be produced in small areas. The Folha Murcha sweet orange has demonstrated high tolerance to CVC, when compared with other sweet orange cultivars. The trials were conducted at the Estação Experimental de Citricultura de Bebedouro, (EECB), and were planted in 2001. Evaluations of plant growth, yield and fruit quality were carried out in all the trials, during three years. In the Folha Murcha trial, additional evaluations of CVC tolerance were conducted. In the non-irrigated trials, tree water deficit tolerance was evaluated by two methods: visual assessment of water stress and direct leaf color measurements. In Tahiti lime, peel color of export fruits was measured and a quantitative methodology was defined as an alternative for current classification criteria, which are based on the subjective visual inspection of external fruit aspect. The horticultural evaluation of Folha Murcha sweet orange, Okitsu Satsuma mandarin and Tahiti lime onto twelve rootstocks allowed to identify the trifoliate rootstocks Flying Dragon, Rubidoux and FCAV as alternatives to Cravo Limeira.
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Improved Vacuum Frying Process for High Quality Sweet Potato ChipsRavli, Yagmur 1985- 14 March 2013 (has links)
Vacuum frying is a promising method for preserving the desired color, texture, and flavor of products with high sugar content. Since most vegetables and fruits degrade when processed with traditional frying, vacuum frying is an excellent alternative to high temperature processing. However, in vacuum frying the product should be pre-treated before frying to obtain a better texture.
The kinetics of oil absorption and oil distribution in sweet potato chips (total, internal, and surface oil content) was studied so that effectiveness of the de-oiling system could be established. An analysis of product quality attributes (PQA) such as moisture content, oil content, microstructure, diameter shrinkage, and thickness expansion, as well as, color, texture, bulk density, true density, and porosity of chips fried at different temperatures (120, 130, and 140°C) was performed to evaluate the effect of process temperature on the product.
The final oil content of the sweet potato chips was 0.178±0.007, 0.178±0.011, and 0.172±0.002 g/g solid for frying temperatures of 120, 130, and 140ºC, respectively. These values were lower (~60% less) than those found in traditionally fried sweet potato chip, which indicates that the de-oiling mechanism is crucial in vacuum frying processing.
It was found that the rate of change in PQAs is greatly affected by temperature; however, the final values of bulk density, true density, porosity, diameter shrinkage, and thickness expansion were not affected by temperature. The texture of the samples was affected by temperature, with the chips fried at 140 degrees C being crispier. In terms of color, the L* and color b* values decreased as temperature increased. While color a* was not affected by temperature.
In this study, a two-stage frying process was also evaluated to improve the flavor and texture of sweet potato chips. First, a basket filled with the sweet potato slices was submerged into the oil under atmospheric conditions. As soon as the potato slices were partially cooked (1 min), the pressure was lowered to 1.33 kPa (vacuum frying stage) and the product fried for 2 more min. The products were fried at 130 degrees C for different interval of times. Starch gelatinization, texture, moisture content, and oil content were evaluated at each time interval. Sensory analysis was accomplished by using a consumer panel with 50 members. The samples were compared with the on-stage frying and atmospheric frying processes.
The two-stage fried chips had better appearance and texture compared to the ones that were only fried under vacuum or atmospheric conditions. The samples were lighter and more yellow than the chips fried under the single-stage process. In vacuum frying, the temperature of the chips does not reach the gelatinization temperature until most of the water is evaporated. Therefore, there is not sufficient moisture content in the product for gelatinization to occur completely. As a result, the product has a glassy texture. In the two stage frying, the atmospheric frying prior to vacuum frying helps the starch to gelatinize thus producing a better product in terms of texture, oil content, and flavor. The atmospheric fried samples were darker in color and had a scorch taste. The degree of starch gelatinization was 21% higher for the two-stage fried samples than the single-stage fried ones.
The application of the dual stage enhances the quality of sweet potato chips, improves consumer satisfaction, and reduces the need for space, cost, and any other needs of blanching pre-treatment to the sweet potato manufacturers.
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Spatial Ontology for the Production Domain of Petroleum GeologyLiadey, Dickson M. 11 May 2012 (has links)
ABSTRACT
The availability of useful information for research strongly depends on well structured relationships between consistently defined concepts (terms) in that domain. This can be achieved through ontologies. Ontologies are models of the knowledge of specific domain such as petroleum geology, in a computer understandable format. Knowledge is a collection of facts. Facts are represented by RDF triples (subject-predicate-object). A domain ontology is therefore a collection of many RDF triples, which represent facts of that domain. The SWEET ontologies are upper or top-level ontologies (foundation ontologies) consisting of thousands of very general concepts. These concepts are obtained from of Earth System science and include other related concepts. The work in this thesis deals with scientific knowledge representation in which the SWEET ontologies are extended to include wider, more specific and specialized concepts used in Petroleum Geology. Thus Petroleum Geology knowledge modeling is presented in this thesis.
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Worst Case Execution time Analysis Support for the ARM Processor Using GCCYen, Cheng-Yu 09 August 2010 (has links)
This thesis presents a tool for obtaining worst-case execution time (WCET) guarantees for ARM processors. This tool is an interface between ARM¡¦s GCC compiler and the SWEET WCET analyzer. SWEET is an open-source static analyzer that derives a guaranteed upper bound on the WCET of a program.
The WCET of a program is an important metric in real-time systems. The task scheduler must decide how much time to allot for each process; if the allotted time exceeds the WCET, the process can be guaranteed to always finish in time. Although the WCET value is therefore useful, it is difficult to find. But, for the purpose of guaranteeing that a process finishes on time, an upper bound on the WCET suffices. Static program analysis has been proposed as a method to derive such an upper-bound on the WCET, by means of conservatively approximating the runtime of the individual parts of a complete program. SWEET is one such static analyzer.
Our tool works inside of ARM-GCC, extracting all of the information that SWEET needs about the program¡¦s behavior. Our tool then packages the information into the SWEET¡¦s ALF format. The tool has been tested and works correctly for every input source that we have tested (including all 34 benchmarks from the WCET BENCHMARK SUITE[1]).
This work was funded by Taiwan¡¦s National Science Council, grant NSC 97-2218-E-110-003
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Molecular cloning of mitogen-activated protein kinase cDNA and study of ethylene signaling in senescent sweet potato leavesShen, Che-yu 08 April 2011 (has links)
Ethylene is a plant growth regulator and plays a key role in leaf senescence. Its signaling, however, remains mostly unclear in sweet potato. Ethephon, an ethylene releasing compound, induced sweet potato detached leaf senescence and associated gene expression, and the effects were repressed by mitogen-activated protein kinase (MAPK) kinase inhibitor PD98059. These data suggest that MAPK cascade is likely involved in ethylene signaling leading to leaf senescence and associated gene expression. With gene-specific primers and RT-PCR methods, a full-length cDNA, SPMAPK, was isolated from ethephon-treated sweet potato leaves. SPMAPK contained 1098 nucleotides (365 amino acids) in the open reading frame. Sweet potato SPMAPK also exhibited high amino acid sequence identities (ca. 79.8% to 83.4%) with plant MAPKs, and was most close to Arabidopsis MPK3 and MPK6 in phylogenetic tree analysis. RT-PCR analysis showed that SPMAPK gene expression was detected in roots, stems, and leaves. The mature and partial yellowing leaves expressed higher amount. SPMAPK gene expression was also inducible and significantly enhanced by ethephon. Results from studies with inhibitors or effectors showed that ethephon treatment resulted in acceleration of leaf senescence in detached sweet potato leaves, promotion of leaf chlorophyll content reduction and decrease of photochemical Fv/Fm, and induction of associated gene expression. These ethephon-mediated effects were all delayed or repressed by pretreatment with ethylene receptor inhibitor 1-methylcyclopropene (1-MCP), MAPK kinase inhibitor PD98059, NADPH oxidase inhibitor diphenyleneiodonium (DPI), antioxidant reduced glutathione, calcium ion chelator EGTA, and de novo protein synthesis inhibitor cycloheximide, respectively. Based on these results we conclude that an ethylene-inducible mitogen-activated protein kinase SPMAPK was isolated from sweet potato leaves, and expressed higher amount in mature and partial yellowing leaves. Ethephon-induced sweet potato SPMAPK expression was significantly repressed by 1-MCP, PD98059, DPI, reduced glutathione, EGTA and cycloheximide. These data also suggest that the possible signal components in ethephon-mediated leaf senescence and associated gene expression in sweet potato leaves likely include ethylene receptor, MAPK cascade, elevated H2O2 , external calcium influx, and de novo synthesized proteins. A possible ethylene signaling model leading to sweet potato leaf senescence and associated gene expression was also proposed.
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Characterization of a sweet potato calmodulin that participates in ethephon and salt stress-mediated leafLin, Zhe-Wei 18 November 2011 (has links)
Ethylene is a gaseous growth regulator, and plays an important role in response to plant developmental and environmental stimuli. Ethylene also plays a key role in leaf senescence. Calcium is a second message, and participates in the signal transduction pathways of many plant physiological responses. In this research, ethephon, an ethylene-releasing compound, was used to induce sweet potato leaf yellowing, chlorophyll content reduction, photochemical Fv/Fm decrease, H2O2 elevation and senescence-associated gene expression. These ethephon-mediated effects were all delayed or repressed by pretreatment of a calcium ion chelator, EGTA. Treatment with a calcium ionophore A23187 also induced senescence-associated gene expression in sweet potato detached leaves, and the induction was repressed by EGTA pretreatment. Calcium signaling in general is transmitted by calcium sensor proteins, including calmodulin to translate into appropriate responses to developmental and environmental stimuli. Therefore, pretreatment with calmodulin inhibitor chlorpromazine (CPZ) delayed or repressed ethephon-mediated leaf senescence, H2O2 elevation and senescence-associated gene expression. These CPZ-mediated effects were reversed by the exogenous application of an ethephon-inducible calmodulin SPCAM fusion protein. These results suggest that external Ca2+ influx and calmodulin SPCAM play a role in ethephon signaling leading to leaf senescence, H2O2 elevation and senescence-associated gene expression. In addition, NaCl salt stress also caused sweet potato leaf senescence, H2O2 elevation and senescence-associated gene expression. Pretreatment with CPZ delayed or repressed NaCl salt stress-mediated leaf senescence, H2O2 elevation and senescence-associated gene expression. These CPZ-mediated effects were also reversed by the exogenous application of calmodulin SPCAM fusion protein. These results suggest that calmodulin SPCAM may play a role in NaCl salt stress signaling leading to leaf senescence, H2O2 elevation and senescence-associated gene expression. Based on these results, external Ca2+ influx is required for ethephon induced leaf senescence. Ethephon-inducible calmodulin SPCAM likely participates in ethylene and NaCl salt stress signaling leading to leaf senescence, H2O2 elevation and senescence-associated gene expression in sweet potato in order to cope with different developmental cues or environmental stimuli.
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Reduced glutathione and NADPH oxidase inhibitor DPI alleviates ethephon-mediated leaf senescence, H2O2 elevation and senescence-associated gene expression in sweet potatoHuang, Chin-shu 23 November 2011 (has links)
Ethylene has long been considered as the main plant growth regulator that plays a key role in the regulation of leaf senescence. In sweet potato, ethephon, an ethylene releasing compound, promoted leaf senescence and H2O2 elevation. These ethephon-mediated effects were alleviated or attenuated by exogenous reduced glutathione and ascorbic acid. Ethephon treatment gradually increased endogenous total and reduced glutathione and ascorbic acid levels in sweet potato detached leaves 3 days after treatment. The H2O2 amount, however, was also increased at 72 h after treatment. Sweet potato detached leaves pretreated with reduced glutathione did significantly increased endogenous total and reduced glutathione levels at 24 h and remarkably decreased H2O2 amount at 72 h after ethephon application compared to that of ethephon alone control. Ethephon caused quick elevation of a small H2O2 peak at about 4 h after application, and the enhancement was eliminated by reduced glutathione pretreatment in treated sweet potato leaves. Pretreatment of diphenylene iodonium (DPI), an NADPH oxidase inhibitor, also repressed leaf senescence and H2O2 elevation at day 3 after ethephon treatment in sweet potato detached leaves, and the attenuation was effective within the first 4 h after ethephon treatment. For senescence-associated gene expression, ethephon and L-buthionine sulfoximine (BSO), an endogenous glutathione synthase inhibitor, did induced asparaginyl endopeptidase (SPAE) and cysteine proteases (SPCP1, SPCP2 and SPCP3) gene expression and the activation was repressed by reduced glutathione pretreatment. Based on these data we conclude that ethephon treatment may cause quick elevation of a small H2O2 peak likely via the NADPH oxidase, which may function as a signal component leading to leaf senescence, H2O2 elevation and senescence-associated gene expression in sweet potato detached leaves. The rate of endogenous antioxidant such as reduced glutathione elevation is also important and affects leaf senescence, H2O2 elevation and senescence-associated gene expression in sweet potato leaves.
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Integrating the SWEET WCET Analyzer into ARM-GCC with Extra WCFP Information to Enable WCET-Targeted Compiler OptimizationsHao, Wen-Chuan 23 December 2011 (has links)
Finding the worst-case execution time (WCET) on a hard real-time system is extremely important. Only static WCET analysis can give us an upper bound of WCET which guarantees the deadline, however, industrial practice still relies on measurement-based WCET analysis, even for many hard real-time systems; because static analysis tools are not a mature technology.
We use SWEET (SWEdish Execution Time tool) to provide WCET analysis support for the ARM. SWEET is a static WCET analyzer developed by the Mälardalen Real-Time Research Center (MRTC). We modified ARM-GCC to obtain input files in specific format for SWEET: ALF, TCD, and MAP. Besides, for WCET optimization supporting and over-optimizing issue, we modified SWEET to obtain additional worst-case flow path (WCFP) and the second worst-case information.
By testing with benchmark files from [1], our modified ARM-GCC can create correct input files for SWEET, and also the modified SWEET can produce additional worst-case information.
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