985 resultados para Diferences in Diferences


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Succinic acid (SA) is a highly versatile building block that is used in a wide range of industrial applications. The biological production of succinic acid has emerged in the last years as an efficient alternative to the chemical production based on fossil fuels. However, in order to fully replace the competing petro-based chemical process from which it has been produced so far, some challenges remain to be surpassed. In particular, one main obstacle would be to reduce its production costs, mostly associated to the use of refined sugars. The present work is focused on the development of a sustainable and cost-e↵ective microbial production process based on cheap and renewable resources, such as agroindustrial wastes. Hence, glycerol and carob pods were identified as promising feedstocks and used as inexpensive carbon sources for the bioproduction of succinic acid by Actinobacillus succinogenes 130Z, one of the best naturally producing strains. Even though glycerol is a highly available carbon source, as by-product of biodiesel production, its consumption by A. succinogenes is impaired due to a redox imbalance during cell growth. However, the use of an external electron acceptor such as dimethylsulfoxide (DMSO) may improve glycerol metabolism and succinic acid production by this strain. As such, DMSO was tested as a co-substrate for glycerol consumption and concentrations of DMSO between 1 and 4% (v/v) greatly promoted glycerol consumption and SA production by this biocatalyst. Aiming at obtaining higher succinic acid yield and production rate, batch and fed-batch experiments were performed under controlled cultivation conditions. Batch experiments resulted in a succinic acid yield on glycerol of 0.95 g SA/g GLY and a production rate of 2.13 g/L.h, with residual production of acetic and formic acids. In fed-batch experiment, the SA production rate reached 2.31 g/L.h, the highest value reported in the literature for A. succinogenes using glycerol as carbon source. DMSO dramatically improved the conversion of glycerol by A. succinogenes and may be used as a co-substrate, opening new perspectives for the use of glycerol by this biocatalyst. Carob pods, highly available in Portugal as a residue from the locust bean gum industry, contain a significant amount of fermentable sugars such as sucrose, glucose and fructose and were also used as substrate for succinic acid production. Sugar extraction from raw and roasted carobs was optimized varying solid/water ratio and extraction time, maximizing sugar recovery while minimizing the extraction of polyphenols. Kinetic studies of glucose, fructose and sucrose consumption by A. succinogenes as individual carbon sources till 30 g/L were first determined to assess possible metabolic diferences. Results showed no significant diferences related to sugar consumption and SA production between the diferent sugars. Carob pods water extracts were then used as carbon source during controlled batch cultivations. (...)

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La hipercalciuria idiopática (HI) es un trastorno metabólico frecuente, con curso clínico, la mayoría de las veces asintomático. Sin embargo, en algunos pacientes se manifiesta clínicamente con hematuria, polaquiuria, disuria, incontinencia urinaria, enuresis y dolor abdominal o lumbar, los cuales afectan las actividades diarias de los niños y motivan consultas médicas repetitivas, con los costos que esto genera. Se requiere de la sospecha clínica y el conocimiento de la enfermedad para su diagnóstico y tratamiento oportunos. Objetivo. Determinar los factores relacionados con el desarrollo de la forma sintomática de HI, para lo cual se estudiaron: la magnitud de la calciuria, el antecedente familiar de urolitiasis, el género, la edad y la excreción de oxalato de calcio. El propósito final fue ampliar y difundir el conocimiento de la enfermedad dentro de la comunidad médica. Materiales y métodos. Se realizó un estudio analítico de casos y controles para determinar la relación existente entre los factores mencionados y la presencia de síntomas de HI. La población de estudio estuvo compuesta por 60 pacientes con diagnóstico establecido de HI, de la consulta de Nefropediatría de la Fundación Cardioinfantil, con edades entre los 2 y los 13 años. La metodología consistió en un estudio no pareado con 1,4 casos por cada control. Para el análisis estadístico de las asociaciones entre los factores en estudio y la HI sintomática se utilizó la prueba exacta de Fisher y el Ji cuadrado de Pearson con un nivel de significancia del 5% (p<0,05). Para establecer la fuerza de la asociación se calculó la razón de disparidad (OR) y el intervalo de confianza del 95%. Además, se determinaron las variables que explican en conjunto la HI sintomática, controlando las variables de confusión con un modelo de regresión logística incondicional a un nivel de significancia del 5% (p<0,05). Resultados. Se establecieron asociaciones entre los siguientes factores y la presencia de síntomas de HI en niños: el género masculino (p = 0,006; OR = 6,2; IC = 1,6-24,5) y la magnitud de la calciuria (p = 0,003). Con menor diferencia estadística se encontraron el antecedente familiar positivo de urolitiasis (p = 0,018; OR = 4,889; IC = 1,26-19,48) y el incremento en la edad (p = 0,044). La presencia de oxalato de calcio en el uroanálisis no se relacionó con los síntomas de HI (p = 0,2; OR = 0,59; IC = 0,17-1,49). Conclusiones. Los valores elevados de calciuria M(mayor a 6 mg/kg/día) y el género masculino, se asocian con la presencia de síntomas de HI en niños. Adicionalmente, se observaron, con frecuencia, en el grupo de pacientes sintomáticos, la presencia de niños de edades mayores y el antecedente familiar positivo de litiasis renal, aunque no se evidencian diferencias significativas para estos dos factores. El hallazgo de cristales de oxalato de calcio en el uroanálisis no se relacionó con los síntomas de HI.

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El ausentismo laboral es un problema para la economía de las empresas y para la sociedad en general, su principal causa son las enfermedades de origen común. Los costos totales son difíciles de cuantificar por la cantidad de factores que influyen en él. METODOLOGIA: Estudio descriptivo de corte transversal que caracterizó el ausentismo laboral teniendo como fuente la base de datos de una empresa del sector terciario de la economía Colombiana, dedicada a las telecomunicaciones a nivel nacional. Se tomó como población universo 3.647 trabajadores a mitad de año de 2013. La población objeto de estudio la conformaron 889 trabajadores que se incapacitaron desde el 1 de enero de 2013 al 31 de diciembre de 2013. RESULTADOS: Se presentaron por enfermedad común 1.097 (83,87%)incapacidades, 740 (83,24%) incapacitados y 7.526 (57,28%) de días perdidos. Las mujeres son las que presentaron mayor número de incapacidades 63,3% (694). Según la clasificación de grupos diagnósticos del CIE 10, el sistema que generó mayor número de días perdidos fue el osteomuscular con el 13,40%. El diagnostico individual que genero mayor número de días perdidos fue el trastorno mixto de ansiedad y depresión 4% (301). Los trabajadores con cinco o más incapacidades durante el año fueron 26 (3,51%) que generaron el 33,3% (2.506) de los días perdidos. Los accidentes de trabajo no son una causa importante de ausentismo. RECOMENDACIONES: Implementar un sistema de recolección de información del ausentismo que se alimente de manera sistemática y continua para tener información suficiente, oportuna y confiable que permita analizarla y generar planes de acción. revisar las actividades que la empresa ha implementado para identificar, evaluar, gestionar los factores de riesgo psicolaborales; optimizar la detección temprana y prevención de desórdenes musculo esqueléticos. Por último realizar monitoreo evaluación y seguimiento a los trabajadores que presentan más de cinco incapacidades durante el año, con un grupo de salud interdisciplinario que permita implementar acciones de promoción y prevención de salud.

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El ausentismo laboral es un problema para la economía de las empresas y para la sociedad en general, su principal causa son las enfermedades de origen común. Los costos totales son difíciles de cuantificar por la cantidad de factores que influyen en él. METODOLOGIA: Estudio descriptivo de corte transversal que caracterizó el ausentismo laboral teniendo como fuente la base de datos de una empresa del sector terciario de la economía Colombiana, dedicada a las telecomunicaciones a nivel nacional. Se tomó como población universo 3.647 trabajadores a mitad de año de 2013. La población objeto de estudio la conformaron 889 trabajadores que se incapacitaron desde el 1 de enero de 2013 al 31 de diciembre de 2013. RESULTADOS: Se presentaron por enfermedad común 1.097 (83,87%)incapacidades, 740 (83,24%) incapacitados y 7.526 (57,28%) de días perdidos. Las mujeres son las que presentaron mayor número de incapacidades 63,3% (694). Según la clasificación de grupos diagnósticos del CIE 10, el sistema que generó mayor número de días perdidos fue el osteomuscular con el 13,40%. El diagnostico individual que genero mayor número de días perdidos fue el trastorno mixto de ansiedad y depresión 4% (301). Los trabajadores con cinco o más incapacidades durante el año fueron 26 (3,51%) que generaron el 33,3% (2.506) de los días perdidos. Los accidentes de trabajo no son una causa importante de ausentismo. RECOMENDACIONES: Implementar un sistema de recolección de información del ausentismo que se alimente de manera sistemática y continua para tener información suficiente, oportuna y confiable que permita analizarla y generar planes de acción. revisar las actividades que la empresa ha implementado para identificar, evaluar, gestionar los factores de riesgo psicolaborales; optimizar la detección temprana y prevención de desórdenes musculo esqueléticos. Por último realizar monitoreo evaluación y seguimiento a los trabajadores que presentan más de cinco incapacidades durante el año, con un grupo de salud interdisciplinario que permita implementar acciones de promoción y prevención de salud.

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Nas últimas décadas, a indústria alimentar tem demonstrado uma grande capacidade de desenvolvimento, quer nas metodologias de produção dos géneros alimentícios, quer nos meios de controlo da segurança dos alimentos. A contaminação e desenvolvimento de microrganismos é uma preocupação sempre presente na indústria de produtos cárneos. De modo a controlar este problema garantindo a inocuidade microbiológica e a estabilidade comercial dos alimentos, o uso de boas práticas de fabrico associadas a tecnologias de conservação são essenciais. Dado que os produtos cárneos fatiados são alimentos mais susceptíveis ao desenvolvimento microbiano, influenciando a sua qualidade e segurança, neste estudo, visou-se comparar a evolução microbiológica do fiambre em peça e fatiado e a influência dos conservantes no prolongamento da vida útil garantindo a segurança do consumidor, para este efeito, avaliou-se a qualidade higiénico-sanitária do fiambre bem como o efeito do diacetato de sódio na estabilidade microbiológica do mesmo, durante o seu período de vida útil sob temperaturas de refrigeração diferenciadas. Os resultados obtidos demonstraram que os fiambres analisados não demonstraram a presença de microrganismos patogénicos. No entanto, o fiambre fatiado revelou a presença de microrganismos de deterioração, não se verificando, contudo, diferenças significativas entre o fiambre teste e controlo.

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O presente trabalho tem por objetivo abordar o tema microcrédito e analisar sua experiência mais bem sucedida no Brasil, o CrediAMIGO, do Banco do Nordeste. Há uma descrição do programa e uma análise quantitativa de sua atuação, que será feita a partir de uma base de dados composta pelas pesquisas Ecinf de 1997 e 2003, utilizando regressões logísticas e o método de diferenças em diferenças. Em termos substantivos concluímos que há experiência de microcrédito na região mais pobre do Brasil, baseada em aval solidário, proporcionando aumento no acesso a crédito superior ao resto do país.

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This work investigates the impact of schooling Oil income distribution in statesjregions of Brazil. Using a semi-parametric model, discussed in DiNardo, Fortin & Lemieux (1996), we measure how much income diíferences between the Northeast and Southeast regions- the country's poorest and richest - and between the states of Ceará and São Paulo in those regions - can be explained by differences in schooling leveIs of the resident population. Using data from the National Household Survey (PNAD), we construct counterfactual densities by reweighting the distribution of the poorest region/state by the schooling profile of the richest. We conclude that: (i) more than 50% of the income di:fference is explained by the difference in schooling; (ii) the highest deciles of the income distribution gain more from an increase in schooling, closely approaching the wage distribution of the richest region/state; and (iii) an increase in schooling, holding the wage structure constant, aggravates the wage disparity in the poorest regions/ states.

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We develop and calibrate a model where diferences in factor en-dowments lead countries to trade di¤erent goods, so that the existence of international trade changes the sectorial composition of output from one country to another. Gains from trade re ect in total factor productivity. We perform a development decomposition, to assess the impact of trade and barriers to trade on measured TFP. In our sample, the median size of that e¤ect is about 6.5% of output, with a median of 17% and a maximum of 89%. Also, the model predicts that changes in the terms of trade cause a change of productivity, and that efect has an average elasticity of 0.71.

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O presente estudo objetiva averiguar a possibilidade de diferentes organizações escolares de provocarem modificações nos traços não-cognitivos de clientela de classe social baixa. Efetuou-se wna comparação entre gr~pos de alunos filhos de operários frequentando os cursos de,~trendiZagem de menores do Serviço Naeibnal de Aprendizagem Indpstrial (SENAI) e de alUnos com caracterIsticas sociais e edu~;iionaiS similaresde escolas acadêmicas da cidade do Rio de Jªne·· ' • • -. ".. ._....... '.> '- .... ,~. Os dados oriundos da observação revelaram que' o SENAI soube capitalizar as experiências da empresa industrial, aparelhando-se metodologicamente para moldar o aprendiz segundo os traços de conduta reclamados pelo mundo do trabalho. As escolas acadêmicas analisadas, embora proclamem objetivos mais amplos a auto-realização do educando, não possuem a infra-estrutura material e humana para tal, chegando mesmo a provocar nos uma atitude de aversão ã escola. alunos Os resultados quantitativos evidenciaram maiores esc~ res em modernidade para os alunos da escola acadêmica, enquanto que na escala de autoritarismo não houve diferenças significativas entre os dois grupos.

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Water injection is the most widely used method for supplementary recovery in many oil fields due to various reasons, like the fact that water is an effective displacing agent of low viscosity oils, the water injection projects are relatively simple to establish and the water availability at a relatively low cost. For design of water injection projects is necessary to do reservoir studies in order to define the various parameters needed to increase the effectiveness of the method. For this kind of study can be used several mathematical models classified into two general categories: analytical or numerical. The present work aims to do a comparative analysis between the results presented by flow lines simulator and conventional finite differences simulator; both types of simulators are based on numerical methods designed to model light oil reservoirs subjected to water injection. Therefore, it was defined two reservoir models: the first one was a heterogeneous model whose petrophysical properties vary along the reservoir and the other one was created using average petrophysical properties obtained from the first model. Comparisons were done considering that the results of these two models were always in the same operational conditions. Then some rock and fluid parameters have been changed in both models and again the results were compared. From the factorial design, that was done to study the sensitivity analysis of reservoir parameters, a few cases were chosen to study the role of water injection rate and the vertical position of wells perforations in production forecast. It was observed that the results from the two simulators are quite similar in most of the cases; differences were found only in those cases where there was an increase in gas solubility ratio of the model. Thus, it was concluded that in flow simulation of reservoirs analogous of those now studied, mainly when the gas solubility ratio is low, the conventional finite differences simulator may be replaced by flow lines simulator the production forecast is compatible but the computational processing time is lower.

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Avaliou-se a reação de contraimunoeletroforese (CIE) como teste gênero-específico para diagnóstico da leptospirose suína, usando-se três extratos solúveis de Leptospira sp, sorovares pomona, icterohaemorrhagiae e patoc, obtidos pelo tratamento com Triton X-100 a quente e aplicados a amostras de soro de suínos subdivididos em três grupos: Grupo 1, 10 suínos experimentalmente infectados com estirpe Pomona; Grupo 2, 50 suínos naturalmente infectados e Grupo 3, controle. As amostras de soros foram submetidas à reação de CIE e os resultados comparados aos da Soroaglutinação Microscópica (SAM), técnica de referência pela WHO. Os Grupos 1 e 3 foram monitorados por 93 dias após a inoculação (p.i.). Pela SAM a soroconversão do Grupo 1 ocorreu por volta do 10º dia p.i., enquanto pela CIE, empregando-se qualquer extrato antigênico, foi anterior à SAM. Quando a CIE foi realizada frente a antigeno homólogo à infecção, seus resultados foram equivalentes aos da SAM, não se verificando o mesmo frente aos antígenos heterólogos. Neste aspecto, os Grupos 1 e 3 mostraram comportamento diferente pois não houve diferença significativa entre os resultados da CIE frente aos três antígenos, o que poderia significar serem independentes do sorovar responsável pelo surto ou infectante. Embora a CIE seja segura, rápida, de fácil execução, de baixo custo e ideal para análise em grande escala de amostras, revelou-se de limitada capacidade gênero-específica, o que não é desejavel para testes de triagem de campo; mas poderia ser útil na detecção precoce de resposta sorológica em relação à SAM.

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Central Nervous System are the most common pediatric solid tumors. 60% of these tumors arise in posterior fossa, mainly in cerebellum. The first therapeutic approach is surgical resection. Malignant tumors require additional strategies - chemotherapy and radiotherapy. The increasing survival evidences that childhood brain tumors result in academic and social difficulties that compromise the quality of life of the patients. This study investigated the intellectual functioning of children between 7 to 15 years diagnosed with posterior fossa tumors and treated at CEHOPE - Recife / PE. 21 children were eligible - including 13 children with pilocytic astrocytoma (G1) who underwent only surgery resection, and eight children with medulloblastoma (G2) - submitted to surgical resection, chemotherapy and craniospinal radiotherapy. Participants were evaluated by the Wechsler Intelligence Scale for Children - WISC-III. Children of G1 scored better than children of G2. Inferential tools (Mann-Whitney Ü Test) identified significant diferences (p ≤ 0.05) between the Performance IQ (PIQ) and Processing Speed Index (PSI) as a function of treatment modality; Full Scale IQ (FSIQ), PIQ and PSI as a function of parental educational level; PIQ, FSIQ, IVP and Freedom from Distractibility (FDI) as a function of time between diagnosis and evaluation. These results showed the late and progressive impact of radiotherapy on white matter and information processing speed. Furthermore, children whose parents have higher educational level showed better intellectual performance, indicating the influence of xxii socio-cultural variables on cognitive development. The impact of cancer and its treatment on cognitive development and learning should not be underestimated. These results support the need to increase the understanding of such effects in order to propose therapeutic strategies which ensure that, in addition to the cure, the full development of children with this pathology

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Two-level factorial designs are widely used in industrial experimentation. However, many factors in such a design require a large number of runs to perform the experiment, and too many replications of the treatments may not be feasible, considering limitations of resources and of time, making it expensive. In these cases, unreplicated designs are used. But, with only one replicate, there is no internal estimate of experimental error to make judgments about the significance of the observed efects. One of the possible solutions for this problem is to use normal plots or half-normal plots of the efects. Many experimenters use the normal plot, while others prefer the half-normal plot and, often, for both cases, without justification. The controversy about the use of these two graphical techniques motivates this work, once there is no register of formal procedure or statistical test that indicates \which one is best". The choice between the two plots seems to be a subjective issue. The central objective of this master's thesis is, then, to perform an experimental comparative study of the normal plot and half-normal plot in the context of the analysis of the 2k unreplicated factorial experiments. This study involves the construction of simulated scenarios, in which the graphics performance to detect significant efects and to identify outliers is evaluated in order to verify the following questions: Can be a plot better than other? In which situations? What kind of information does a plot increase to the analysis of the experiment that might complement those provided by the other plot? What are the restrictions on the use of graphics? Herewith, this work intends to confront these two techniques; to examine them simultaneously in order to identify similarities, diferences or relationships that contribute to the construction of a theoretical reference to justify or to aid in the experimenter's decision about which of the two graphical techniques to use and the reason for this use. The simulation results show that the half-normal plot is better to assist in the judgement of the efects, while the normal plot is recommended to detect outliers in the data

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The objective of this research is to know the conscience, the sensibility and the interperformance's vision man-environment of some residents from Areado's slum, theirs attitudes and motivations to link individual and collectively with their environment seeking ransom the diferences and compare them in relacion of an scientific look. The study to the valorization of experience from individual or from the group consisted of humanist approach of Geography having the phenomenology as underlying philosophy. The theorical formulations manifested from ideas whole, detaching the effort to discipline the use at least these concepts: landscape, space, place and environment. Opposite the importance of knowing the interelation manenvironment, we insert more two concepts: topofilia (felling joins people to the place where they lives) and topophobia, because our preoccupations in the ambit of evironmental question, immediate to the human beings. The research had been developed from interview and percepition workshop, when the interviewed people answered about they understand what are environiment and Areado's environment. The gotten results allow a reflection about the evironmental thought thinking found there, constituting in subsidy to programs of evironmental education that be worried about local problems

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The cage farming of aquatic organisms was initiated 50 years ago, and was introduced to Brazil in the 1990's. In these systems, there is an input of organic matter from ration that is not totally used by the cage fishes, becoming available for the organisms of adjacent biota, including fish fauna. The aim of this work is to evaluate the interference in the diet of three dominant fish species (Plagioscion squamosissimus Heckel, 1840, Astyanax altiparanae Garutti and Britski, 2000 and Metynnis maculatus Kner, 1858) associated with ish cage farming. For determination of the diet, the Alimentary Index (AI) was used. In both stretches (around cage farm and control), P. squamosissimus selected aquatic insects, while A. altiparanae preferred terrestrial insects and M. maculatus eats ration remains. Diferences in abundance of these feeding resources found of the stomach content were observed among the two stretches. Thus, the small alterations in the diets of P. squamosissimus and A. altiparanae, indicate that cage farming can change the diet of resident species in reservoirs. This practice also influences the population structure of fish species, since higher middle standard lengths were found in A. altiparanae and P. squamosissimus populations resident around cage farms, in relation to the control stretch.