973 resultados para 12930-040


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Lucas (1987) has shown a surprising result in business-cycle research: the welfare cost of business cycles are very small. Our paper has several original contributions. First, in computing welfare costs, we propose a novel setup that separates the effects of uncertainty stemming from business-cycle fluctuations and economic-growth variation. Second, we extend the sample from which to compute the moments of consumption: the whole of the literature chose primarily to work with post-WWII data. For this period, actual consumption is already a result of counter-cyclical policies, and is potentially smoother than what it otherwise have been in their absence. So, we employ also pre-WWII data. Third, we take an econometric approach and compute explicitly the asymptotic standard deviation of welfare costs using the Delta Method. Estimates of welfare costs show major differences for the pre-WWII and the post-WWII era. They can reach up to 15 times for reasonable parameter values -β=0.985, and ∅=5. For example, in the pre-WWII period (1901-1941), welfare cost estimates are 0.31% of consumption if we consider only permanent shocks and 0.61% of consumption if we consider only transitory shocks. In comparison, the post-WWII era is much quieter: welfare costs of economic growth are 0.11% and welfare costs of business cycles are 0.037% - the latter being very close to the estimate in Lucas (0.040%). Estimates of marginal welfare costs are roughly twice the size of the total welfare costs. For the pre-WWII era, marginal welfare costs of economic-growth and business- cycle fluctuations are respectively 0.63% and 1.17% of per-capita consumption. The same figures for the post-WWII era are, respectively, 0.21% and 0.07% of per-capita consumption.

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Lucas(1987) has shown a surprising result in business-cycle research: the welfare cost of business cycles are very small. Our paper has several original contributions. First, in computing welfare costs, we propose a novel setup that separates the effects of uncertainty stemming from business-cycle uctuations and economic-growth variation. Second, we extend the sample from which to compute the moments of consumption: the whole of the literature chose primarily to work with post-WWII data. For this period, actual consumption is already a result of counter-cyclical policies, and is potentially smoother than what it otherwise have been in their absence. So, we employ also pre-WWII data. Third, we take an econometric approach and compute explicitly the asymptotic standard deviation of welfare costs using the Delta Method. Estimates of welfare costs show major diferences for the pre-WWII and the post-WWII era. They can reach up to 15 times for reasonable parameter values = 0:985, and = 5. For example, in the pre-WWII period (1901-1941), welfare cost estimates are 0.31% of consumption if we consider only permanent shocks and 0.61% of consumption if we consider only transitory shocks. In comparison, the post-WWII era is much quieter: welfare costs of economic growth are 0.11% and welfare costs of business cycles are 0.037% the latter being very close to the estimate in Lucas (0.040%). Estimates of marginal welfare costs are roughly twice the size of the total welfare costs. For the pre-WWII era, marginal welfare costs of economic-growth and business-cycle uctuations are respectively 0.63% and 1.17% of per-capita consumption. The same gures for the post-WWII era are, respectively, 0.21% and 0.07% of per-capita consumption.

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Buscando melhorar as condições de vida dos municípios mineiros, o governo estadual mineiro instituiu, em 1995, a lei 12.040, conhecida como Lei Robin Hood. Esta permitia que 25% dos recursos de ICMS a serem distribuídos aos municípios mineiros se dessem sobre resultados observáveis em diversas áreas tais como saúde, educação, conservação ecológica, entre outras. Ou seja, instituia, em relação a estas transferências, um contrato de alto poder com os municípios relacionados às políticas públicas implementadas. O estudo destas transferências (relativas à educação e saúde) mostrou um forte impacto positivo na primeira (e inexistente na segunda). Dada a relativa escassez deste tipo de contrato em transferências federativas, este resultado aponta a necessidade de utilização de instrumentos de maior poder nas relações federativas, buscando incrementar as condições de vida locais.

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Oil well cementing materials consist of slurries of Special class Portland cement dispersed in water. Admixtures can be used to provide the necessary fluidity, so the material can be efficiently pumped down as well as penetrate porous rocks with controlled filter loss. Construction admixtures can be used to modify the properties of oil well cements provided they can withstand and hold their properties at the higher than ambient temperatures usually encountered in oil fields. In civil construction, superplasticizer play the role of dispersants that reduce the facto r of water cement improve mechanical properties and fluidity of the cement, whereas anti-segregation agents improve the workability of the slurry. In the present study, oil well cement slurries were produced adding both a dispersant and an anti-segregation agent conventionally used in Portland CPII-Z-32 RS cement aiming at materials for primary cementing and squeeze operations. Three basic aspects were evaluated: fluidity, filter loss and the synergetic effect of the admixtures at two temperatures, i.e., 27°C and 56°C, following API RP 10B practical recommendations. The slurries were prepared using admixture concentrations varying from 2.60 Kgf/m3 (0.02 gallft3) to 5.82 Kgf/m3 (0.045 galJft3) BWOC. The density of the slurries was set to 1.89 g/cm3 (15.8 Ib/gal). 0.30 to 0.60% BWOC of a CMC-based anti-segregation agent was added to the cement to control the filter loss. The results showed that the addition of anti-segregation at concentrations above 0.55% by weight of cement resulted in the increased viscosity of the folders in temperatures evaluated. The increasing the temperature of the tests led to a reduction in the performance of anti-segregation. At concentrations of 5.20 kgf/m3 (0,040 gallft3) and 5.82 Kgf/m3 (0,045 gal/ft 3) observed a better performance of the properties evaluated in the proposed system. At low temperature was observed instability in the readings of rheology for all concentrations of anti-segregation. Contents that increasing the concentration of anti¬-segregation is limited concentrations greater than 0.55 % BWOC of the CMC in temperature analyzed. The use of the system with CMC promoted a good performance against the properties evaluated. The principal function of anti¬-segregation was optimized with increasing concentration of superplasticizer, at temperatures above the 2rC. The study of the behaviour of systemic additives, resulting in slurries of cement, which can be optimized face studies of other intrinsic properties in oil fields

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In the last decades, the oil, gas and petrochemical industries have registered a series of huge accidents. Influenced by this context, companies have felt the necessity of engaging themselves in processes to protect the external environment, which can be understood as an ecological concern. In the particular case of the nuclear industry, sustainable education and training, which depend too much on the quality and applicability of the knowledge base, have been considered key points on the safely application of this energy source. As a consequence, this research was motivated by the use of the ontology concept as a tool to improve the knowledge management in a refinery, through the representation of a fuel gas sweetening plant, mixing many pieces of information associated with its normal operation mode. In terms of methodology, this research can be classified as an applied and descriptive research, where many pieces of information were analysed, classified and interpreted to create the ontology of a real plant. The DEA plant modeling was performed according to its process flow diagram, piping and instrumentation diagrams, descriptive documents of its normal operation mode, and the list of all the alarms associated to the instruments, which were complemented by a non-structured interview with a specialist in that plant operation. The ontology was verified by comparing its descriptive diagrams with the original plant documents and discussing with other members of the researchers group. All the concepts applied in this research can be expanded to represent other plants in the same refinery or even in other kind of industry. An ontology can be considered a knowledge base that, because of its formal representation nature, can be applied as one of the elements to develop tools to navigate through the plant, simulate its behavior, diagnose faults, among other possibilities

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The soil erodibility factor is represented by the integrated effect of processes that regulate the water infiltration, soil resistance and the transport of soil particles. Therefore, this study had as objective to estimate the soil erodibility in the Corrego do Tijuco watershed, São Paulo State, Brazil, for guiding farmers in decision making for application of techniques for soil conservation. The soil samples were collected in a regular spacing of 500 m, resulting in a total of 310 points in a 0-20.0 m depth in an area of approximately 8,000 ha. For the estimation of soil erodibility (K) was applied a mathematical model which takes into account the soil organic matter content, the sand and silt size fractions, the soil permeability, and the particle mean diameter for each point of soil sampling. Estimated values greater than 0.040 Mg ha h ha(-1) MJ(-1) mm(-1) were considered very high for this factor. In areas with greater degree of erodibility occurs the Argisols order predominance, that shows high susceptibility to the development of interrill erosion due to its remarkable performance in relation to textural gradient, thereby, the interrill erosion rates can be very intensive due to rapid saturation of upper horizon, increasing the erosion process. At the Latosols (Oxisols) areas were also observed high soil erodibility values that under inappropriate conditions of soil occupation, concentrating runoff of rain water, leading to appear deep gullies.

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A parreira-brava (Cissampelos glaberrima) e a erva-palha (Blainvillea romboidea) estão no início de sua dispersão na cultura da cana-de-açúcar no Estado de São Paulo e são espécies de extrema agressividade e de difícil controle. Objetivou-se neste trabalho estudar a eficácia dos herbicidas trifloxysulfuron-sodium + ametryne, picloram + 2,4-D, 2,4-D e fluroxypyr, aplicados em pós-emergência, no controle de parreira-brava e ervapalha em canaviais. O delineamento experimental utilizado foi o de blocos casualizados, com seis tratamentos e quatro repetições. Foram feitas avaliações visuais das porcentagens de controle, aos 7, 14, 21, 29, 36, 42, 56 e 90 dias após a aplicação (DAA) dos herbicidas. Medidas das alturas das plantas de cana-de-açúcar foram feitas aos 29 e 56 DAA, e a contagem do número de afilhos foi feita aos 33 DAA. Na colheita, fez-se a contagem do número de colmos, e a produção foi calculada através da pesagem dos colmos da parcela. Diante dos resultados obtidos, pode-se concluir que o trifloxysulfuron-sodium + ametryne (1.500 g ha-1) agiu rápida e eficientemente na parte aérea das plantas adultas de parreirabrava, porém não impediu que as brotações surgissem após os 42 dias da aplicação. No entanto, o picloram + 2,4-D (a 2.040 g ha-1) e o fluroxypyr (345 g ha-1) mantiveram níveis de controle da parreira-brava superiores a 90%, até 90 DAA. O controle de erva-palha mostrouse não-satisfatório com a aplicação de trifloxysulfuron-sodium + ametryne e bastante eficaz (100%) com os demais herbicidas.

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Objetivou-se avaliar a substituição do milho em grão pela polpa cítrica peletizada e seus efeitos sobre os ganhos de peso, as taxas de deposição e a composição química corporal de tourinhos Santa Gertrudes em confinamento. Vinte e oito animais (idade média de nove meses e peso inicial de 277 kg) foram mantidos em baias individuais durante 92 dias, após 21 dias de adaptação. Os animais receberam dietas contendo 20% da MS como silagem de milho que continha 40% de grãos. Foram testados os níveis de 0, 25, 40 e 55% de participação da polpa cítrica peletizada na MS da dieta. A composição química corporal foi estimada a partir de equações desenvolvidas para a mesma raça, utilizando-se a composição química do corte da 9-10-11ª costelas. A participação da polpa cítrica peletizada não afetou significativamente o peso corporal final (449 kg) e os ganhos diários de peso corporal (1,50 kg), de corpo vazio (1,26 kg) e de carcaça (0,78 kg). Não houve diferença entre tratamentos para as taxas diárias de deposição de água (0,374 kg), EE (0,589 kg), proteína (0,253 kg), minerais (0,040 kg) e energia (6,934 Mcal) e, conseqüentemente, a composição química corporal final foi similar entre os animais recebendo diferentes níveis de polpa cítrica na dieta. A substituição do milho em grão por polpa cítrica peletizada, até 55% da MS, em dietas para tourinhos em terminação recebendo altos níveis de concentrado, não altera os ganhos de peso, as taxas de deposição e a composição química corporal desses animais.

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Objective: To examine the effects of treadmill inclinations on the walking of hemiparetic chronic subjects. Design: Observational descriptive study. Location: Laboratory of human movement analysis. Participants: Eighteen subjects, 10 men and 8 women were evaluated, with a mean age of 55.3 ± 9.3 years and the time since the injury of about 36 ± 22.8 months. Intervention: Not applicable. Main Outcome Measures: All subjects were evaluated for functional independence (Functional Independence Measure - FIM) and balance (Berg Balance Scale). Angular variations of the hips, knees and ankles in the sagittal plane were observed, as well as the speed of the movement (m/s), cadence (steps/min), stride length (m), cycle time (s), step time on the paretic leg and on the non-paretic leg (s), support phase time and balance phase time on the paretic leg (s) and the ratio of symmetry inter-limb as subjects walked on a treadmill at three conditions of inclination (0%, 5% and 10% ). Results: There were angular increases in the initial contact of the hip, knee and ankle, amplitude increase in the hip between 0% and 10% (37.83 ± 5.23 versus 41.12 ± 5.63, p < 0,001) and 5% and 10% (38.80 ± 5.96 versus 41.12 ± 5.63, p = 0,002), amplitude increases in the knee between 0% and 10% (47.51 ± 15.07 versus 50, 30 ± 12.82, p = 0,040), extension decreases in the hip, dorsiflexion increases in the balance phase and in the time of support phase from 0% to 5% (0.83 ± 0.21 versus 0.87 ± 0, 20, p = 0,011) and 0% and 10% (0.83 ± 0.21 versus 0.88 ± 0.23, p = 0,021). Conclusion: The treadmill inclination promoted angle changes as such as the increase of the angle of the hip, knee and ankle during the initial contact and the balance phase and the increase of the range of motion of the hip and knee; furthermore, it also promoted the increase of the support time of the paretic lower limb

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The tumor hypoxia modulates a series of genetic changes related to adaptive development, invasion and metastasis of various human cancers, among which squamous cell carcinoma of the tongue (SCCT). The objective of this study was to analyze clinical, morphological and immunohistochemical expression by HIF-1α, GLUT-1 and CA-IX in 57 cases of CEL and correlated this expression to clinical parameters and morphological. After a descriptive analysis of data on gender, age, race, and habits of patients, it was found that the results were consistent with the literature. The clinical and morphological parameters analyzed and the expression of these markers of hypoxia were subjected to statistical analysis (Qui2 test), verifying that they can be used as indicators of the biological behavior of CEL. Among the results of this study, we observed that the intensity of expression for HIF-1α, in most cases located in the cytoplasm and nucleus, statistically correlated with clinical staging (p = 0.011) and histological grading (p = 0.002). As for the relationship between the distribution of labeling for HIF-1α and metastasis, the chi-square (Qui2) showed that there was statistically significant differences between the groups (p = 0.040). 75.8% of the sample who had metastases, there was the predominance of diffuse marking. The immunoexpression cytoplasmic/membrane GLUT-1 showed a statistically significant correlation with the clinical stage (p = 0.002) and histological grading (p = 0.000). Concerning the location of markings for GLUT-1 tumor on the island, there was a predominance of peripheral marking specimens in most low-grade (78.6%). In the sample of high-grade, prevailed the location center/periphery (55.8%). According to the chi-square (Qui2), the location on the island of the tumor (p = 0.025) showed statistically significant difference in histological grading. The immunoreactivity of CA-IX, in most cases located in the membrane and cytoplasm, exhibited a statistically significant correlation with histological grading (p = 0.005). Based on these results, we can conclude a broad participation of these markers of hypoxia in oral carcinogenesis and its possible use as markers of biological behavior and tumor progression in CEL

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Squamous cell carcinoma of the lower lip is among the most common malignant tumors of the oral and maxillofacial region, with good prognosis in more than 90% of patients with 5-year survival. In these carcinomas, the development of lymph node metastasis decreases the prognosis and it has been associated with the formation of new lymphatic vessels. It has been suggested the important role of vascular endothelial growth factor-C (VEGF-C), the receptor type 3 VEGF (VEGFR-3) and hypoxia-induced factor 1 (HIF-1) in this process. The aim of this study was to evaluate the immunoexpression of VEGF-C, VEGFR-3 and HIF-1α and correlate with intra and peritumoral lymphatic density in squamous cell carcinomas of the lower lip metastatic and non-metastatic. The sample consisted of 50 cases of squamous cell carcinoma of lower lip, of which 25 had regional lymph node metastasis and 25, absence of metastasis. The percentages of cells immunostained for VEGF-C, VEGFR-3 and HIF-1α in front of tumor invasion and in the center of tumor were evaluated. Microvessel density lymphatic (MDL) was determined by the counting of lymph microvessels immunostained by the anti-D2-40 in five fields (200×), in an area of evaluation with 0.7386 mm2. The invasion of the lymph vessels by malignant cells was also evaluated. Immunostaining was correlated with the presence and absence of metastasis, TNM clinical stage, local recurrence, disease outcome (remission of injury or patient death) and histological grading. The analysis of intra and peritumoral lymphatic density showed no significant association with clinicopathological parameters and immunoexpressions of VEGF-C, VEGFR-3 and HIF-1α (p > 0,05). There was a weak positive correlation, significant, between intra and peritumoral lymphatic density (r = 0,405; p = 0,004). VEGF-C showed no significant association with clinicopathological and prognosis parameters (p > 0,05). For VEGFR-3, there was scarce membrane staining and intense and homogenous cytoplasmic staining in neoplastic cells. Percentage of positive cytoplasmic VEGFR-3 in center of tumor, exhibited a statistically significant association with metastasis (p = 0,009), patient death (p = 0,008) and histological grades of malignancy proposed by Bryne et al. (1992) (p = 0,002) and World Health Organization (p = 0,003). A low positive correlation was statistically significant between the immunoreactivity of VEGFC and VEGFR-3 cytoplasmic (r = 0,358; p = 0,011) and between the percentage of positive cytoplasmic VEGFR-3 in front of tumor invasion and in the center of the tumor (r = 0,387; p = 0,005) was also demonstrated. There was no association between HIF-1α, clinicopathological and prognosis parameters, and VEGF-C and VEGFR-3. The percentage of nuclear positivity for HIF-1α was significantly higher in cases without invasion of peritumoral lymphatic (p = 0,040). Based on the results we can conclude that most cytoplasmic expression of VEGFR-3 in center of tumor in metastatic cases, high degree of malignancy and poorly differentiated, contributes to poor outcome of squamous cell carcinoma of the lower lip, including patient death. Intra and peritumoral lymphatic density seems to be not associated with lymph node metastasis in these carcinomas

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The existence of an interpolating master action does not guarantee the same spectrum for the interpolated dual theories. In the specific case of a generalized self-dual (GSD) model defined as the addition of the Maxwell term to the self-dual model in D = 2 + 1, previous master actions have furnished a dual gauge theory which is either nonlocal or contains a ghost mode. Here we show that by reducing the Maxwell term to first order by means of an auxiliary field we are able to define a master action which interpolates between the GSD model and a couple of non-interacting Maxwell-Chern-Simons theories of opposite helicities. The presence of an auxiliary field explains the doubling of fields in the dual gauge theory. A generalized duality transformation is defined and both models can be interpreted as self-dual models. Furthermore, it is shown how to obtain the gauge invariant correlators of the non-interacting MCS theories from the correlators of the self-dual field in the GSD model and vice-versa. The derivation of the non-interacting MCS theories from the GSD model, as presented here, works in the opposite direction of the soldering approach.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)