942 resultados para univariate and multivariate yield indices
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Abscisic acid (ABA) is an important phytohormone with regulatory roles in many physiological processes. ABA expression is induced by environmental stresses such as drought and it is known to be an inhibitor of seed germination. A wild oat (Avena fatua) called AFN1 has been hypothesized to initiate the early stages of germination as its mRNA accumulates in nondormant seed embryos during imbibition. The polypeptide sequence of AFN1 suggests that it is an ABA glucosyl transferase. Glucosylation by AFN1 and thereby inactivation of ABA could lead to seed germination. In order to understand the role of AFN1 in germination, an ample quantity of AFN1 polypeptide is needed to test for enzymatic ABA glucosylase activity. My work has been to overexpress recombinant AFN1containing a (His)6 tag using a pRSETC E.coli expression system followed by Purification of the AFN1 protein by means of a nickel-affinity column that bind to the (His)6 tag. Due to the insufficient yield of AFN1 fusion protein obtained with this procedure, another method using a pMAL-c2x vector is now being employed. The pMAL expression system provides a method for expressing and purifying protein by tagging proteins with maltose-binding protein (MBP). It is anticipated that MBP tag will be advantageous as it can make the fusion protein more soluble and thereby yield a larger quantity of protein. Currently, work is underway on the construction of pMAL/AFN1 plasmid.
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This thesis is composed of three articles with the subjects of macroeconomics and - nance. Each article corresponds to a chapter and is done in paper format. In the rst article, which was done with Axel Simonsen, we model and estimate a small open economy for the Canadian economy in a two country General Equilibrium (DSGE) framework. We show that it is important to account for the correlation between Domestic and Foreign shocks and for the Incomplete Pass-Through. In the second chapter-paper, which was done with Hedibert Freitas Lopes, we estimate a Regime-switching Macro-Finance model for the term-structure of interest rates to study the US post-World War II (WWII) joint behavior of macro-variables and the yield-curve. We show that our model tracks well the US NBER cycles, the addition of changes of regime are important to explain the Expectation Theory of the term structure, and macro-variables have increasing importance in recessions to explain the variability of the yield curve. We also present a novel sequential Monte-Carlo algorithm to learn about the parameters and the latent states of the Economy. In the third chapter, I present a Gaussian A ne Term Structure Model (ATSM) with latent jumps in order to address two questions: (1) what are the implications of incorporating jumps in an ATSM for Asian option pricing, in the particular case of the Brazilian DI Index (IDI) option, and (2) how jumps and options a ect the bond risk-premia dynamics. I show that jump risk-premia is negative in a scenario of decreasing interest rates (my sample period) and is important to explain the level of yields, and that gaussian models without jumps and with constant intensity jumps are good to price Asian options.
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Nos dias de hoje existe uma grande demanda e pressão na seleção e definição de prioridades das alternativas de investimento para alavancar o crescimento de longo prazo das empresas. Em paralelo a este cenário, o ambiente global está cada vez mais incerto, o que implica que as escolhas realizadas por estas empresas devem se adaptar aos novos desejos do mercado e, principalmente, devem manter o direcionamento de crescimento almejado pelas mesmas. Neste contexto conturbado, as ferramentas tradicionais utilizadas para a tomada de decisão, para selecionar e definir as prioridades são as análises econômico-financeira representadas pelo Valor Presente Líquido, a Taxa Interna de Retorno e o Payback. Apesar de estes itens serem métodos robustos e consistentes na avaliação de projetos de investimentos, eles focam apenas em um aspecto (o financeiro), e as empresas, atualmente, estão envolvidas em ambientes que precisam de uma abordagem mais ampla, contemplando outras visões e dimensões não presentes nos estudos financeiros. Ou seja, quando se faz uma análise de carteira de projetos alinhada ao planejamento estratégico, é necessário realizar uma abordagem multicritério envolvendo indicadores quantitativos e qualitativos e disponibilizando aos tomadores de decisão uma informação completa e padronizada de todos os projetos, uma vez que estas iniciativas não possuem características homogêneas, pois cada uma apresenta sua respectiva particularidade e, principalmente, está em diferentes estágios de maturidade. Aliado a estes pontos, é perceptível que o processo de seleção e priorização de projetos necessita de uma sistematização que garanta a esta decisão e a este Portfólio uma maior estabilidade e fidedignidade das informações. Neste trabalho, portanto, foi elaborada uma análise multivariada, mais especificamente, a utilização de sistemas de apoio à tomada de decisão. Foram escolhidos outros critérios além do econômico-financeiro, para suportar a seleção e priorização de projetos no atendimento dos objetivos estratégicos da organização e de seus stakeholders.
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The objective of this article is to study (understand and forecast) spot metal price levels and changes at monthly, quarterly, and annual frequencies. Data consists of metal-commodity prices at a monthly and quarterly frequencies from 1957 to 2012, extracted from the IFS, and annual data, provided from 1900-2010 by the U.S. Geological Survey (USGS). We also employ the (relatively large) list of co-variates used in Welch and Goyal (2008) and in Hong and Yogo (2009). We investigate short- and long-run comovement by applying the techniques and the tests proposed in the common-feature literature. One of the main contributions of this paper is to understand the short-run dynamics of metal prices. We show theoretically that there must be a positive correlation between metal-price variation and industrial-production variation if metal supply is held fixed in the short run when demand is optimally chosen taking into account optimal production for the industrial sector. This is simply a consequence of the derived-demand model for cost-minimizing firms. Our empirical evidence fully supports this theoretical result, with overwhelming evidence that cycles in metal prices are synchronized with those in industrial production. This evidence is stronger regarding the global economy but holds as well for the U.S. economy to a lesser degree. Regarding out-of-sample forecasts, our main contribution is to show the benefits of forecast-combination techniques, which outperform individual-model forecasts - including the random-walk model. We use a variety of models (linear and non-linear, single equation and multivariate) and a variety of co-variates and functional forms to forecast the returns and prices of metal commodities. Using a large number of models (N large) and a large number of time periods (T large), we apply the techniques put forth by the common-feature literature on forecast combinations. Empirically, we show that models incorporating (short-run) common-cycle restrictions perform better than unrestricted models, with an important role for industrial production as a predictor for metal-price variation.
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This thesis aims to identify how civil servants perceive changes made inthe carrying out of their work after their taking part in the Course forTechnicians in Public Management of the Government of Rio Grande do NorteState. As for the methodological procedures, an exploratory-descriptivequantitative research has been carried out through structured questionnaires appliedto 118 civil servants from the first groups of the Course for Technicians, thusshowing a margin of error of 4.18% to 95% of confidence, according to theprocedures of finite sampling. The table processing and analysis rested uponthe Statistical Package for the Social Sciences SPSS and was carried outthrough univariate, bivariate and multivariate techniques with emphasis on thetechnique called Factor Analysis. It was possible to identify that the level ofsatisfaction of the students was high and there was a clear perception by themthat the course assisted to changes in their work. Through Factor Analysis itwas verified that the factors that may be related to changes in the work of thecivil servants are "Contribution to Society", "Efficiency andEfficacy in the Work Environment", "Applicability of Contents"and "Capacitating for Leadership". The conclusion of the studyindicates that the factors obtained are directly related to the basis of thenew public management by means of guidance toward efficiency and efficacy in aperspective of leadership, the contents of the course being thus made into newattitudes toward work which end up yielding better results for society
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The objective of the present study was to evaluate the effects of different dietary energy levels and stocking densities on the thermoregulating parameters, live performance, and carcass traits of broilers reared under tropical winter conditions at different times of the day. In total, 1,312 one-d-old male broilers were used. Birds were allotted to three different stocking densities (10, 14 or 18 birds/m²) and two dietary energy levels (2900 or 3200 kcal ME/kg). The following parameters were evaluated:radiant heat load (RHL), rectal temperature (RT), feed intake (FI), weight gain (WG), feed conversion ratio (FCR), livability (L), production of live weight per area (WA), and carcass yield. Stocking density did not affect sensible heat loss (SRL) or rectal temperature (RT); however, as expected, sensible heat loss (SRL) and RT were influenced by time of the day, with higher values in the morning and in the afternoon, respectively. There was no effect of treatment (p>0.05) on carcass or parts yield. Feed intake was reduced in 3%, whereas weight gain and feed conversion ratio improved in 8 and 10%, respectively, as dietary energy level increased. on the other hand, stocking density did not influence live performance or carcass traits. Based on the present results, it is concluded that sensible heat loss depends on dietary energy levels and particularly on time of the day. Therefore, environmental house management is suggested during tropical winters in order to reduce differences between broiler skin and environmental temperatures in the morning and in the afternoon.
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Objetivou-se nesta pesquisa avaliar o desempenho, o rendimento de carcaça e a morfometria intestinal de frangos de corte criados em diferentes temperaturas e que receberam na fase pré-inicial ração contendo ou não extrato de leveduras e prebiótico. Foram utilizados 1.440 pintos machos de 1 dia de idade, criados em diferentes câmaras climáticas. As rações, acrescidas ou não de extrato de leveduras e prebiótico, foram oferecidas somente na fase pré-inicial (1 a 7 dias). A partir do oitavo dia, todas as aves receberam a mesma ração, reajustada de acordo com as recomendações usuais. Adotou-se o delineamento experimental inteiramente casualizado em arranjo fatorial 3 × 2 × 2, composto de três temperaturas de criação (calor, conforto e frio) e dois níveis de extrato de leveduras (com ou sem) e prebiótico (com ou sem). O desempenho das aves foi avaliado considerando o ganho de peso, o consumo de ração, a conversão alimentar e a viabilidade aos 42 dias de idade. Também foram avaliados o rendimento de carcaça e a morfometria intestinal. O calor ambiente prejudicou o desempenho e o rendimento de carcaça. A inclusão de prebiótico na ração pré-inicial aumentou o ganho de peso e melhorou a conversão alimentar das aves criadas no calor. A inclusão dos produtos na ração de frangos de corte criados em ambiente de calor e no frio tem efeito benéfico sobre as vilosidades das aves.
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In order to evaluate the effect of energy intake and broiler genotype on performance, carcass yield, and fat deposition, 600 one-day-old male chicks from two different genetic groups (AgRoss 308 - commercial line and PCLC - Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) non-improved line) were fed diets with different metabolizable energy level (2950, 3200 and 3450 kcal/kg). A completely randomized experimental design in a 2X3 factorial arrangement with four replications of 25 birds per treatment was applied. In order to ensure different energy intake among treatments within each strain, feed intake was daily adjusted by pair-feeding schemes. AgRoss 308 broilers had better performance and carcass yield, and presented lower abdominal fat deposition rate. In both genetic groups, the highest dietary energy level increased weight gain, heart relative weight, and fat deposition. However, it reduced the difference between AgRoss 308 and PCLC for feed conversion ratio and carcass protein deposition. These findings allow concluding that genetic improvement had a significant effect on broiler energy metabolism, and that the highest performance differences between genetic groups are found when low-energy intake is imposed.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Parent, L. E., Natale, W. and Ziadi, N. 2009. Compositional nutrient diagnosis of corn using the Mahalanobis distance as nutrient imbalance index. Can. J. Soil Sci. 89: 383-390. Compositional nutrient diagnosis (CND) provides a plant nutrient imbalance index (CND - r(2)) with assumed chi(2) distribution. The Mahalanobis distance D(2), which detects outliers in compositional data sets, also has a chi(2) distribution. The objective of this paper was to compare D(2) and CND - r(2) nutrient imbalance indexes in corn (Zea mays L.). We measured grain yield as well as N, P, K, Ca, Mg, Cu, Fe, Mn, and Zn concentrations in the ear leaf at silk stage for 210 calibration sites in the St. Lawrence Lowlands [2300-2700 corn thermal units (CTU)] as well as 30 phosphorus (2300-2700 CTU; 10 sites) and 10 nitrogen (1900-2100 CTU; one site) replicated fertilizer treatments for validation. We derived CND norms as mean, standard deviation, and the inverse covariance matrix of centred log ratios (clr) for high yielding specimens (>= 9.0 Mg grain ha(-1) at 150 g H(2)O kg(-1) moisture content) in the 2300-2700 CTU zone. Using chi(2) = 17 (P < 0.05) with nine degrees of freedom (i.e., nine nutrients) as a rejection criterion for outliers and a yield threshold of 8.6 Mg ha(-1) after Cate-Nelson partitioning between low- and high-yielders in the P validation data set, D(2) misclassified two specimens compared with nine for CND -r(2). The D(2) classification was not significantly different from a chi(2) classification (P > 0.05), but the CND - r(2) classification differed significantly from chi(2) or D(2) (P < 0.001). A threshold value for nutrient imbalance could thus be derived probabilistically for conducting D(2) diagnosis, while the CND - r(2) nutrient imbalance threshold must be calibrated using fertilizer trials. In the proposed CND - D(2) procedure, D(2) is first computed to classify the specimen as possible outlier. Thereafter, nutrient indices are ranked in their order of limitation. The D(2) norms appeared less effective in the 1900-2100 CTU zone.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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An experiment was conducted to evaluate the performance and carcass yield of broilers at 55 days of age fed diets with different levels of metabolizable energy and lysine. Evaluated data of performance were weight gain, feed intake, energy intake, lysine intake, caloric conversion and feed conversion. Carcass assessment was performed based on data from carcass yield, breast weight, whole wings, whole legs, back, head + neck, feet and abdominal fat. A 3 x 3 factorial arrangement was used, with 3 levels of metabolizable energy (3,200; 3,400 and 3,600 kcal ME/kg) and 3 lysine levels (0.95%; 1.05% and 1.15%). There was no interaction between the two factors. Nevertheless, increasing levels of metabolizable energy improved weight gain (745 g; 841 g and 910 g, respectively) and feed intake was higher in broilers receiving the diets with 3,200 and 3,600 kcal ME/kg. Overall performance was not affected by lysine levels. Feed conversion values were 2.69, 2.42 and 2.14 for birds fed diets with 3,200; 3,400 and 3,600 kcal ME/kg, respectively. Carcass yield and breast weight increased with higher levels of energy and lysine in the diets.
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Foi realizado um ensaio utilizando 36 suínos machos castrados, com peso inicial de 83,7±5,1kg, para avaliar o efeito da inclusão de polpa cítrica, 0, 10, 20 e 30%, em um programa de restrição alimentar qualitativa para suínos abatidos aos 130kg de peso, sobre o peso dos órgãos do sistema digestório e sobre características da carcaça e da qualidade da carne. A inclusão de polpa cítrica proporcionou aumento linear (P<0,05) nos pesos do estômago, cólon e fígado, e efeito quadrático (P<0,05) no peso do ceco. Foi observada redução linear (P<0,05) no peso, no rendimento da carcaça e no peso do pernil, porém não houve efeito (P>0,05) sobre o rendimento do pernil. Maior inclusão de polpa cítrica não foi suficiente para reduzir a espessura do toucinho e aumentar a quantidade de carne magra na carcaça, mostrando que a restrição alimentar qualitativa não foi eficiente. Foi observado aumento linear (P<0,05) do pH da carcaça resfriada e linear negativo (P<0,05) sobre as variáveis indicativas de cor da carne em função da inclusão da polpa cítrica nas dietas. A adição de polpa cítrica em programas de restrição alimentar qualitativa não foi eficiente. Por não promover nenhum efeito deletério sobre as características da carne, a polpa cítrica pode ser utilizada como ingrediente alternativo para suínos em terminação.