The effects of inter-crop cultivation Between rows of citrus crop on spreading of Guignardia citricarpa Ascospores and in the citrus black spot occurrence

This study highlighted the effect of planting coast-cross grass and forage peanut cv. Amarilis between rows of Natal oranges on spreading of Guignardia citricarpa ascospores and consequent citrus black spot control. Treatments evaluated were: 1- conventional cultivation, free of fungicides; 2- conventional cultivation, using protective fungicides; 3- inter-crop cultivation of coast-cross grass between rows of citrus crops and; 4- inter-cropping cultivation of forage peanut between the rows of citrus crops. Quest Volumetric Spore SystemTM traps were set in order to determine the number of ascospores released. A total of 33 inspections were conducted weekly, from the end of August until early September the following year. A diagrammatic scale was used to determine the severity of the disease as well as the percentage of fruits having a commercial standard. The coast-cross grass was more effective in reducing the number of ascospores produced, whose average statistics were lower than in the conventional treatments, free-fungicides. The inter-crop and conventional cultivation method coupled with fungicide treatment was more effective in reducing the severity of citrus black spot symptoms, and differs statistically from the fungicide-free control method. These methods also resulted in a higher percentage of fruits of a commercial standard, ranging from the 89% through the 91% percentile, and the cultivation, free of fungicides, fell within the 73%.

Evaluation of a revision of the BSPcast decision support system for control of brown spot of pear

Control of brown spot of pear requires fungicide treatments of pear trees during the growing season. Scheduling fungicide sprays with the Brown spot of pear forecasting system (BSPcast) provides significantfungicide savings but does not increase the efficacy of disease control. Modifications in BSPcast wereintroduced in order to increase system performance. The changes consisted of: (1) the use of a daily infectionrisk (Rm≥0.2) instead of the 3-day cumulative risk (CR≥0.4) to guide the fungicide scheduling, and (2) theinclusion of the effect of relative humidity during interrupted wetness periods. Trials were performed during2 years in an experimental pear orchard in Spain. The modifications introduced did not result in increaseddisease control efficacy, compared with the original BSPcast system. In one year, no reduction in the numberof fungicide applications was obtained using the modified BSPcast system in comparison to the original system, but in the second year the number of treatments was reduced from 15 to 13. The original BSPcast model overestimated the daily infection risk in 6.5% of days with wetness periods with low relative humidity during the wetness interruption, and in these cases the modified version was more adequate

Analysis of outliers in electricity spot prices with exampleof New England and New Zealand markets

Electricity spot prices have always been a demanding data set for time series analysis, mostly because of the non-storability of electricity. This feature, making electric power unlike the other commodities, causes outstanding price spikes. Moreover, the last several years in financial world seem to show that ’spiky’ behaviour of time series is no longer an exception, but rather a regular phenomenon. The purpose of this paper is to seek patterns and relations within electricity price outliers and verify how they affect the overall statistics of the data. For the study techniques like classical Box-Jenkins approach, series DFT smoothing and GARCH models are used. The results obtained for two geographically different price series show that patterns in outliers’ occurrence are not straightforward. Additionally, there seems to be no rule that would predict the appearance of a spike from volatility, while the reverse effect is quite prominent. It is concluded that spikes cannot be predicted based only on the price series; probably some geographical and meteorological variables need to be included in modeling.

Highly functional binding surface for miniaturised solid-phase immunoassays. - A spot story -

Several bioaffinity assays are based on the detection of an analyte which is bound on a solid substrate via biochemical interaction. These so called solid phase assays are based on the adhesion of the primary binding partner on a solid surface, which then binds the analyte to be detected. In this thesis work a novel solid phase based assay technology, known as spot technology, was developed. The spot technology is based on combination of high-capacity solid phases, concentrated in a spot format, utilising modified streptavidin molecules and recombinant antibody fragments. The reduction of the solid phase binding surface to a size of a spot enabled denser binding of the target molecules, providing improved signal intensities and signal-to-background ratio when applied in different solid phase immunoassays. Streptavidin-biotin interactions are commonly utilised in numerous different bioaffinity assays and the ultimate nature of streptavidin to bind biotin is among the strongest non-covalent interaction reported between two biomolecules. In this study native core streptavidin was chemically modified to provide polymerised streptavidin molecules with altered adsorption properties. These streptavidin conjugates, when coated onto polystyrene surface, provided enhanced biotin binding capacity and surface stability when compared to a reference coating constructed with native streptavidin. Furthermore, the combination of chemically modified streptavidin, sitespecifically biotinylated antibody fragments and the spot coating technology provided highly dense solid phase coating with improved binding properties. The performance of the spot assay technology was further demonstrated in different immunoassay configurations. Human thyroid stimulating hormone (TSH) and human cardiac troponin I (cTnI) were used as model analytes to show the applicability of the highly sensitive spot-based solid-phase immunoassay for detection of very low levels of analytes. It was demonstrated that the spot technology provided an assay concept with enhanced sensitivity and short turn-around times, characteristics that are highly suitable for point-of-care applications.

Prognosis of after spot volumes at the Scandinavian electricity market

The Thesis is dedicated to development of an operative tool to support decision making in after spot trading on the Nordic electricity market. The basics of the Nordic electricity market, trading mechanisms on the spot and after spot markets are presented in the Thesis. Mathematical equations that describe electricity balance condition in the power system are offered. The main driving factors that impact deviation of actual electricity balance from the scheduled one (object) in the power system have been explored and mathematically defined. The behavioral model of the object and principal trends in change of state of the object under an impact of the driving factors are determined with the help of regression analysis made in Microsoft Office Excel. The behavioral model gives an indication for the total regulation volume (Elbas trades volume, volume of regulation market, balance power) for a certain hour that serves as the base input in estimating prices on the after spot markets. Proposals for development of methodologies of forecasting the after spot electricity prices are offered.

Anàlisi d'un spot televisiu segons el model proposat per Frederic Chaume : Estudi d'un cas: Beauty is nothing without brains

L’estudi de les situacions comunicatives sempre m’ha atret de manera significativa. El món de la publicitat, també. L’assignatura de Semiòtica audiovisual ha estat el vincle que ha inspirat el tema d’aquest treball. L’idea inicial era la d’analitzar des d’una perspectiva semiòtica un document audiovisual, concretament, Beauty is nothing without brains, un espot televisiu de Mercedes-Benz emès als Estats Units l’any 2007. Es pretenia identificar i analitzar cadascun dels elements que configuren la comunicació audiovisual i presentar possibles versions traductològiques del mateix. La dificultat de crear un esquema d’anàlisi que em permetés estructurar-ne l’estudi va conduir-me a Frederic Chaume. És llavors quan aconsegueixo concretar el tema del treball: es pretén analitzar aquest document audiovisual seguint el model proposat per Chaume, responent a un hipotètic encàrrec de traducció el qual demana la seva adaptació al mercat català.

Desenvolvimento de um spot test para o monitoramento da atividade da peroxidase em um procedimento de purificação

In this work we describe both a chromatographic purification procedure and a spot test for the enzyme peroxidase (POD: EC 1.11.1.7). The enzyme was obtained from crude extracts of sweet potatoes and the chromatographic enzyme purification procedure resulted in several fractions. Therefore a simple, fast and economic spot test for monitoring peroxidase during the purification procedure was developed. The spot test is based on the reaction of hydrogen peroxide and guaiacol, which is catalyzed by the presence of peroxidase yielding the colored tetraguaiacol.

Método simples para diferenciar Diplodia macrospora de D. maydis em testes de patologia de sementes de milho

Descreve-se neste trabalho um método para diferenciar Diplodia macrospora de D. maydis em testes de patologia de sementes de milho (Zea mays). Os sintomas da podridão branca em espigas e grãos de milho infetados por esses fungos são idênticos, porém, os patógenos diferem, principalmente, pela coloração das colônias desenvolvidas a partir de sementes de milho infetadas. As sementes foram desinfestadas com hipoclorito de sódio e dispostas em gerbox, contendo três camadas de papel-de-filtro embebido com água esterilizada e colocadas em câmara de crescimento a 25 ± 2 ºC. A diagnose foi baseada na coloração das colônias desenvolvidas sobre o papel-de-filtro. Após 15 dias de incubação, as colônias de D. macrospora permaneceram com coloração branca a bege, enquanto as de D. maydis, que originalmente eram brancas, tornaram-se de pardo-escuras a escuras com formação de picnídios. Conclui-se que muitos trabalhos feitos em patologia de sementes de milho referentes a D. maydis podem ter incluído na diagnose as duas espécies por não dispor-se de um método que possibilite a diferenciação segura entre os dois patógenos.

Epidemiology of apple leaf spot

Apple leaf spot (ALS) caused by Colletotrichum spp. is a major disease of apple (Malus domestica) in Southern Brazil. The epidemiology of this disease was studied in experiments carried out in the counties of Passo Fundo and Vacaria, State of Rio Grande do Sul, from February 1998 to October 2000. The disease was found in all the six apple orchards sampled in the growing seasons of 1997/98 and 1998/99. The fungus isolates associated with ALS fit the characteristics of C. gloeosporioides (75%), C. acutatum (8%), and Colletotrichum sp. (17%). The pathogen overwintered in dormant buds and twigs but not in dropped leaves or fruit mummies. Two sprays of copper oxychloride (at 0.3%) reduced the fungus initial inoculum by 65-84.6% in buds and 85.6-93.7% in twigs, but had no effect on the early season progress of the disease. Disease severity increased proportionally to elevation of temperature from 14 to 26-28 °C. At 34 °C, however, infection was completely inhibited. The duration of leaf wetness required for infection ranged from two hours at 30 °C to 32 h at 16 °C. The relationship of temperature (T) and leaf wetness (W) to disease severity (Y) was represented by the model equation Y = 0.00145[((T-13)1.78)((34.01-T )1.09)] * 25/[1+14 exp(-0.137W)], R² = 0.73 and P < 0.0001. Currently, this information is being used to manage the disease and to validate a forecast system for ALS.

Caracterização do Tomato chlorotic spot virus isolado de jiló no Vale do Paraíba, Estado de São Paulo

Os tospovírus são responsáveis por perdas significativas em diversas culturas, principalmente solanáceas. No município de São José dos Campos (SP), plantas de jiló (Solanum gilo) apresentando sintomas de mosaico, bolhosidades, nanismo e queda acentuada da produção foram coletadas para análise. Visando a caracterização do agente causador dos sintomas, testes biológicos, elétrono microscópicos, sorológicos e moleculares foram realizados. Através de inoculação mecânica em plantas indicadoras das famílias Amaranthaceae, Chenopodiaceae e Solanaceae obtiveram-se resultados típicos aos esperados para tospovírus. Ao microscópio eletrônico de transmissão, observaram-se, em contrastação negativa, partículas pleomórficas com diâmetro entre 80 e 110 nm e em cortes ultra-finos partículas presentes em vesículas do retículo endoplasmático. Através de DAS-ELISA, identificou-se o Tomato chlorotic spot virus (TCSV). A partir de RNA total extraído de folhas infetadas, amplificaram-se, via RT-PCR, fragmentos correspondentes ao gene da proteína do capsídeo (cp) os quais foram seqüenciados e comparados com outros depositados no "GenBank". A homologia de nucleotídeos e aminoácidos deduzidos foi respectivamente de 99 e 95% quando comparada com seqüências de isolados de TCSV. A comparação com as outras espécies do gênero Tospovirus apresentou valores de homologia entre 72 e 84%. Estes resultados confirmam a identidade deste vírus como pertencente à espécie TCSV, que é predominante no Estado de São Paulo e importante patógeno de outras plantas cultivadas. Além disso, variedades de jiló quando inoculadas foram susceptíveis tanto ao TCSV como às espécies Tomato spotted wilt virus (TSWV) e Groundnut ringspot virus (GRSV).

A comparison of electricity spot prices simulation using ARMA-GARCH and mean-reverting models

The aim of this work is to compare two families of mathematical models for their respective capability to capture the statistical properties of real electricity spot market time series. The first model family is ARMA-GARCH models and the second model family is mean-reverting Ornstein-Uhlenbeck models. These two models have been applied to two price series of Nordic Nord Pool spot market for electricity namely to the System prices and to the DenmarkW prices. The parameters of both models were calibrated from the real time series. After carrying out simulation with optimal models from both families we conclude that neither ARMA-GARCH models, nor conventional mean-reverting Ornstein-Uhlenbeck models, even when calibrated optimally with real electricity spot market price or return series, capture the statistical characteristics of the real series. But in the case of less spiky behavior (System prices), the mean-reverting Ornstein-Uhlenbeck model could be seen to partially succeeded in this task.

Mycovellosiella robbsii sp. nov. causing leaf-spot on Mimosa caesalpiniaefolia

This is a description of the new species Mycovellosiella robsii, a cercosporoidal hyphomycete, associated with leaf spots on Mimosa caesalpiniaefolia, an important hedge plant with multiple uses in Brazil. The new species was compared to other cercosporoid species associated with plants of the genus Mimosa and other species of the genus Mycovellosiella described on legumes, and is recognized as a distinct taxon. Koch's postulates were carried out and the disease was reproduced by inoculating healthy plants with mycelial suspension or disk, confirming the pathogenicity. This is the first report of a fungal disease on this host.

Quantificação do inóculo de Diplodia macrospora e de D. maydis em restos culturais, no ar, e sua relação com a infecção em grãos de milho

A quantificação do inóculo de Diplodia macrospora e de D. maydis nos restos culturais do milho (Zea mays)é fundamental para demonstrar a importância desta fonte de inóculo, bem como servir de base para o desenvolvimento de estratégias alternativas de controle. Em experimentos conduzidos no campo, nas safras de verão de 1995/96 e 1996/97, quantificaram-se a quantidade de restos culturais do milho sobre o solo após a semeadura, a densidade de conídiosnos resíduos e o inóculo disseminado pelo ar, bem como a incidência de cada espécie de Diplodia nos grãos de milho colhidos. A quantidade de conídios nos restos culturais foi de 2,1 x 10(5), para D. macrospora, e de 1,0 x 10(5) para D. maydis, no primeiro ano e de 4,2 x 10(5) e 3,4 x 10(6) m-2, respectivamente, no segundo. A dispersão anemófila de conídios foi mais intensa da semeadura até a quarta semana para D. maydis, e da décima semana até a colheita para D. macrospora. O número médio de conídios por cirro foi de 865 para D. macrospora e de 685 para D. maydis. A incidência média nos grãos foi de 75,5% para D. macrospora e de 25,5% para D. maydis. Com este trabalho, observou-se a importância relativa das espécies de Diplodia envolvidas no processo infeccioso de espigas de milho, demonstrando-se que D. macrospora foi a mais freqüente. Comprovou-se também que os restos culturais são necessários à sobrevivência desses patógenos na área cultivada, servindo como fonte de inóculo à infecção da planta e espigas de milho.