941 resultados para Linear coregionalization model
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The objectives of the current study were to investigate the additive genetic associations between heifer pregnancy at 16 months of age (HP16) and age at first calving (AFC) with weight gain from birth to weaning (WG), yearling weight (YW) and mature weight (MW), in order to verify the possibility of using the traits measured directly in females as selection criteria for the genetic improvement of sexual precocity in Nelore cattle. (Co)variance components were estimated by Bayesian inference using a linear animal model for AFC, WG, YW and MW and a nonlinear (threshold) animal model for HP16. The posterior means of direct heritability estimates were: 0.45 +/- 0.02; 0.10 +/- 0.01; 023 +/- 0.02; 0.36 +/- 0.01 and 0.39 +/- 0.04, for HP16, AFC, WG, YW and MW, respectively. Maternal heritability estimate for WG was 0.07 +/- 0.01. Genetic correlations estimated between HP16 and WG, YW and MW were 0.19 +/- 0.04; 0.25 +/- 0.06 and 0.14 +/- 0.05, respectively. The genetic correlations of AFC with WG, YW and MW were low to moderate and negative, with values of -0.18 +/- 0.06; -0.22 +/- 0.05 and -0.12 +/- 0.05, respectively. The high heritability estimated for HP16 suggests that this trait seem to be a better selection criterion for females sexual precocity than AFC. Long-term selection for animals that are heavier at young ages tends to improve the heifers sexual precocity evaluated by HP16 or AFC. Predicted breeding values for HP16 can be used to select bulls and it can lead to an improvement in sexual precocity. The inclusion of HP16 in a selection index will result in small or no response for females mature weight. (C) 2011 Elsevier B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A hierarchical fuzzy control scheme is applied to improve vibration suppression by using an electro-mechanical system based on the lever principle. The hierarchical intelligent controller consists of a hierarchical fuzzy supervisor, one fuzzy controller and one robust controller. The supervisor combines controllers output signal to generate the control signal that will be applied on the plant. The objective is to improve the performance of the electromechanical system, considering that the supervisor could take advantage of the different techniques based controllers. The robust controller design is based on a linear mathematical model. Genetic algorithms are used on the fuzzy controller and the supervisor tuning, which are based on non-linear mathematical model. In order to attest the efficiency of the hierarchical fuzzy control scheme, digital simulations were employed. Some comparisons involving the optimized hierarchical controller and the non-optimized hierarchical controller will be made to prove the efficiency of the genetic algorithms and the advantages of its use
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Objetivou-se neste trabalho avaliar diferentes períodos de controle e de convivência de uma comunidade de plantas daninhas na cultura da batata 'Atlantic'. O experimento foi realizado no município de Botucatu-SP, e o delineamento experimental utilizado foi de blocos ao acaso com quatro repetições. Os tratamentos constituíram-se de seis períodos de controle, nos quais a cultura foi mantida livre da comunidade de plantas daninhas e após cada período, as plantas daninhas foram deixadas crescer livremente; e de seis períodos de convivência, nos quais a cultura foi mantida na presença da comunidade de plantas daninhas e após cada período, as plantas daninhas foram eliminadas até a colheita. Os períodos foram de 7, 14, 21, 28, 35 e 42 dias após o plantio dos tubérculos, além de uma testemunha mantida sempre livre de plantas daninhas e outra mantida sempre na presença dessas plantas. Foram identificadas 9 famílias e 15 espécies de plantas daninhas, com destaque para Bidens pilosa, Galinsoga parviflora,Brachiaria plantaginea,Commelina benghalensis e Digitaria horizontalis. Os resultados de produção de tubérculos ajustaram-se ao modelo de regressão não-linear: y = 8,907+(17,722/[1+(x/16,865)-8,412]), (R² = 0,963*) - equação para os períodos de controle e y = 5,728+(24,789/[1+(x/39,292)2,247 ]), (R² = 0,947*) - equação para os períodos de convivência. Assim, considerando perda de 5% na produtividade como aceitável, foram determinados o período anterior à interferência (PAI), que foi de 20 dias; o período total de prevenção à interferência (PTPI), de 21 dias; e o período crítico de prevenção da interferência (PCPI), de apenas de um dia, dos 20 aos 21 dias após o plantio dos tubérculos.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A simple, sensitive, and specific biodiffusion assay for the! antibacterial ceftazidime was developed using a strain of Staphylococcus epidermidis (ATCC 12228) as the test organism. Ceftazidime was measured in powder for injection at concentrations ranging from 100 to 400 mu g/mL. The calibration graph for ceftazidime was linear (r(2) = 1), and the method validation showed that it was precise (relative standard deviation = 0.415) and accurate. The results obtained by biodiffusion assay were statistically calculated by linear parallel model and by means of regression analysis and were verified using analysis of variance. It was concluded that the microbiological assay is satisfactory for in vitro quantification of the antibacterial activity of ceftazidime in pharmaceuticals.
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Introduction: The aging process causes quantitative and qualitative changes in sleeping. Such changes affects more than half of the adults above 65 years old, that live in the community and 70% of the institutionalized, a great negative impact in their quality of life. One of the pathological displays of aging, that share some characteristics with sleeping disorders and predict similar results, is the Frailty Syndrome, that characterize the most weakened and vulnerable elderly. The way sleeping disorders play a role in the frailty pathogeneses remains uncertain. Objective: Evaluate the relation between the sleeping and the frailty syndrome on institutionalized elderly. Methodology: A transversal study was performed with 69 elderly in institutions in the city of João Pessoa PB. Were used the Pittsburgh Sleeping Quality Index and actigraphy to subjective and objective variables, respectively, and questionnaires and specific tests to frailty phenotype variant (Fried Frailty Criteria). In the statistic analysis were used the Pearson correlation test, Chi Square and One-way ANOVA test, with Tukey-Krammer posttest. Subsequently, a Simple Linear Regression model was built. On every statistical analysis were considered a confidence interval of 95% and a p < 0,05. Results: The sample was characterized by the prevalence of the frail (49,3%), women (62,3%), single (50,7%) and 77,52 (±7,82).The frail elderly obtained the worst sleeping quality 10,37 (±4,31) (f = 4,15, p = 0,02), when compared with the non-frail. The sleep latency influenced more the frailty (R2 = 0,13, β standard = 1,76, β = 0,41, p = 0,001). Weren t found differences between the standard resting-activity variable and the frailty phenotype categories. Conclusion: Sleeping alterations, including bad sleeping quality, prolonged sleep latency, low sleep efficiency and day drowsiness, influenced the frailty in institutionalized elderly
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The term fatigability concerns the degree of fatigue associated with performing an activity of any type (physical, mental, emotional and / or social). Recently scales for assessing fatigue in the English language were created, however, gaps exist regarding the validity of these scales in relation to oxygen consumption and levels of perceived fatigue. Objective: To investigate the validity of perceived fatigability scale in older women frail and non-frail by the expired gases kinetics. Methods: This is a study of type validation, where were evaluated 48 elderly. The evaluation was conducted at two different sessions. In the first, data were collected demographic partners, as well as assessment of cognitive function, physical health, and the phenotype of frailty. The second was composed by the test 6-minute walk (6MWT) associated the expired gases kinects and assessment of perceived fatigability. Statistical analysis was performed a descriptive analysis and then we used the Pearson correlation test to evaluate the relationship between the measure of perceived fatigue and variables oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory exchange ratio (RER)before and after 6MWT. We used a linear regression model initially considering the following explanatory variable: age, Body Mass Index (BMI), presence of frailty, comorbidities, level of physical activity, distance covered in the 6MWT , the energy cost of walking and severity of fatigability on performance. Results: The final sample consisted of 44 elderly women, 4 elderly were excluded because they didn t complete all phases of this study. The mean age obtained was 75 years (± 7.2 years). There was no significant correlation between fatigability measures and the values of VO2 ( r = .09 , p = .56 ) , VCO2 ( r = .173 , p = .26 ) , RER ( r = - .121 , p = .43 ). The final linear regression model showed that the energy cost of walking, the usual level of physical activity and the performance severity of fatigability explained 83.5 % (R2 = 0.835, p < 0.01) of the variation in the perceived fatigability. Conclusion: Our findings indicate a relationship between greater severity of fatigability and lower levels of physical activity and increased energy cost in walking, suggesting that the fatigability analyses using a simple numeric scale is valid and viable for assessment of fatigue in older women
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The objectives of this research were characterizing the dairy goat production systems and model it using linear program. On the first step of this research, the model was developed using data from farms that was affiliated in the ACCOMIG/Caprileite, used a similar dairy goat production systems and have a partnership program with Universidade Federal de Minas Gerais . The data of research were from a structured questionnaire applied with farmers and monitoring of production systems during a guided visit on their farms. The results permitted identify that all farms were classified as a small and have a intensive production system. The average herd size had 63.75 dairy goats on lactation; it permits a production of 153, 38 kg of goat milk per day. It was observed that existing more than one channel of commercialization for the goat milk and their derivative products. The data obtained, on the first step of this research, was used to develop a linear program model. It was evaluated in two goat production systems, called P1 and P2. The results showed that the P1 system, with an annual birth and lactation during approximately 300 days was the best alternative for business. These results were compared with a mixed (beef and dairy) goat system in the semiarid region, which indicated merged with both systems. Therefore, to achieve profits and sustainability of the system, in all simulations it was necessary a minimum limit of funding of U.S. $ 10,000.00; this value permit earning of U.S. $ 792.00 per month and pay the investment within 5 years
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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O objetivo deste trabalho foi estimar os ganhos genéticos de um teste de progênies de seringueira para a produção de borracha seca e, com base no maior tamanho efetivo populacional e maior ganho genético, obter os melhores indivíduos. Foram utilizadas 30 progênies de meios-irmãos, provenientes de sementes de polinização mista - alogamia e autogamia - de testes clonais no Estado de São Paulo. Utilizou-se o delineamento experimental de blocos ao acaso, com 30 tratamentos (progênies), 3 repetições e parcelas lineares de 10 plantas, em um espaçamento de 3x3 m, o que totalizou 900 plantas úteis. Aos três anos, o perímetro, a 50 cm do solo (PA50), e a produção de borracha seca (PBS) foram avaliadas por meio do teste precoce de produção Hamaker Morris-Mann (HMM). As variáveis foram analisadas pelo método de modelo linear misto, via procedimento REML/BLUP, em progênies com sistema reprodutivo misto e taxa de autofecundação de 22%. A identificação dos 20 melhores indivíduos quanto à PBS e ao PA50 proporcionou ganho genético de 67,96 e 16,48%, respectivamente, e um coeficiente de endogamia de aproximadamente 2,82%. O teste de progênies proporciona produção de sementes com melhor valor genético, grande variabilidade e baixa endogamia
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Objective-To compare the ability of a sidestream capnograph and a mainstream capnograph to measure end-tidal CO2 (ETCO2) and provide accurate estimates of Paco(2) in mechanically ventilated dogs.Design-Randomized, double Latin square.Animals-6 healthy adult dogs.Procedure-Anesthesia was induced and neuromuscular blockade achieved by IV administration of pancuronium bromide. Mechanical ventilation was used to induce conditions of standard ventilation, hyperventilation, and hypoventilation. While tidal volume was held constant, changes in minute volume ventilation and Paco(2) were made by changing the respiratory rate. Arterial blood gas analysis was performed and ETCO2 measurements were obtained by use of either a mainstream or a sidestream capnographic analyzer.Results-A linear regression model and bias analysis were used to compare Paco(2) and ETCO2 measurements; ETCO2 measurements obtained by both capnographs correlated well with Paco(2). Compared with Paco(2), mainstream ETCO2 values differed by 3.15 +/- 4.89 mm Hg (mean bias +/- SD), whereas the bias observed with the sidestream ETCO2 system was significantly higher (5.65 +/- 5.57 mm Hg). Regardless of the device used to measure ETCO2, bias increased as Paco(2) exceeded 60 mm Hg.Conclusions and Clinical Relevance-Although the mainstream capnograph was slightly more accurate, both methods of ETCO2 measurement correlated well with Paco(2) and reflected changes in the ventilatory status. However, ETCO2 values > 45 mm Hg may inaccurately reflect the severity of hypoventilation as Paco(2) may be underestimated during conditions of hypercapnia (Paco(2) > 60 mm Hg).
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Objective - Kidney dysfunction is a common complication after cardiac surgery. It occurs in 7 to 31% of the patients. The lowest haematocrit after cardiopulmonary bypass surgery (LHCT) has been identified as a risk factor for kidney dysfunction after cardiac surgery. The aim of this study is to determine whether different levels of haematocrit during cardiopulmonary bypass surgery are related to kidney dysfunction.Methods and results-A prospective study was conducted on consecutive adult patients undergoing myocardial revascularization. Preoperative renal function was assessed by baseline serum creatinine level (CrPre). Peak postoperative creatinine (CrPost) was defined as the highest daily in-hospital postoperative value. Peak fractional change in creatinine (% Delta Cr) was defined as the difference between the CrPre and CrePost represented as a percentage of the preoperative value. The LHTC was defined as the lowest recorded haematocrit prior to weaning from the initial pump run. A category variable was created for haematocrit based on the distribution of values. The category variable had the following cut-off points: less than 23%, 23.1 to 28% and greater than 28.1 %. Lowest haematocrit (26.62 +/- 4.15%), CPB (74.71 +/- 24.90 min), CrPre (1.23 +/- 0.37 mg/dl) and highest CrPost (1.52 +/- 0.47 mg/dl) data varied in near-normal fashion. Statistical significance has been observed in the < 23% lowest haematocrit group (CrIPOD and Cr5POD; P = 0.006) and the 23.1 28% lowest haematocrit level group (CrPre and Cr2POD; P = 0.047). CrPre and Cr5POD did not differ between groups (P > 0.05). The multiple linear regression model confirmed that the determinants for higher %Delta Cr were age, body surface area and preoperative serum creatinine level.Conclusion - The LHTC was not identified as a risk factor for kidney dysfunction after myocardial revascularization.
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In this work we have developed a way to grow Fe/MgO(100) monocrystals by magnetron sputtering DC. We investigated the growing in a temperature range among 100 oC and 300 oC. Structural and magneto-crystalline properties were studied by different experimental techniques. Thickness and surface roughness of the films were investigated by atomic force microscopy, while magneto-crystalline properties were investigated by magneto-optical Kerr effect and ferromagnetic resonance. Our results show that as we increase the deposition temperature, the magneto-crystalline anisotropy of the films also increases, following the equation of Avrami. The best temperature value to make a film is 300 oC. As the main result, we built a base of magnetoresistence devices and as an aplication, we present measurements of Fe/Cr/Fe trilayer coupling. In a second work we investigated the temperature dependence of the first three interlayer spacings of Ag(100) surface using low energy electron diffraction. A linear expansion model of crystal surface was used and the values of Debye temperatures of the first two layers and thermal expansion coefficient were determinated. A relaxation of 1% was found for Ag(100) surface and these results are matched with faces (110) and (111) of the silver. iv
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OBJETIVO: Pesquisar um fator de correção para avaliação do erro refrativo sem a utilização da cicloplegia. MÉTODOS: Foram estudados 623 pacientes (1.246 olhos), de ambos os sexos, com idade entre 3 e 40 anos. As refratometrias estática e dinâmica foram obtidas usando-se o refrator automático Shin-Nippon Accuref-K 9001. A cicloplegia foi obtida com a instilação de uma gota de colírio ciclopentolato a 1%, com refratometria estática 30 minutos após. Os dados foram submetidos à análise estatística usando a técnica do modelo de regressão linear e modelo de regressão múltipla do valor dióptrico com e sem cicloplegia, em função da idade. RESULTADOS: A correlação entre valores dióptricos sem e com cicloplegia quanto ao erro astigmático variou de 81,52% a 92,27%. Quanto ao valor dióptrico esférico, a correlação foi menor (53,57% a 87,78%). O mesmo se observou em relação ao eixo do astigmatismo (28,86% a 58,80%). O modelo de regressão múltipla em função da idade mostrou coeficiente de determinação múltiplo maior para a miopia (86,38%) e astigmatismo (79,79%). O menor coeficiente foi observado para o eixo do astigmatismo (17,70%). CONCLUSÃO: Avaliando-se os erros refrativos com e sem cicloplegia, observou-se alta correlação nas ametropias cilíndricas. Foram desenvolvidas equações matemáticas como fator de correção para refratometrias dos pacientes sem cicloplegia, portadores de ametropias cilíndricas e esféricas.