988 resultados para Hermite Associated Functions


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Cropp and Gabric [Ecosystem adaptation: do ecosystems maximise resilience? Ecology. In press] used a simple phytoplanktonzooplankton-nutrient model and a genetic algorithm to determine the parameter values that would maximize the value of certain goal functions. These goal functions were to maximize biomass, maximize flux, maximize flux to biomass ratio, and maximize resilience. It was found that maximizing goal functions maximized resilience. The objective of this study was to investigate whether the Cropp and Gabric [Ecosystem adaptation: do ecosystems maximise resilience? Ecology. In press] result was indicative of a general ecosystem principle, or peculiar to the model and parameter ranges used. This study successfully replicated the Cropp and Gabric [Ecosystem adaptation: do ecosystems maximise resilience? Ecology. In press] experiment for a number of different model types, however, a different interpretation of the results is made. A new metric, concordance, was devised to describe the agreement between goal functions. It was found that resilience has the highest concordance of all goal functions trialled. for most model types. This implies that resilience offers a compromise between the established ecological goal functions. The parameter value range used is found to affect the parameter versus goal function relationships. Local maxima and minima affected the relationship between parameters and goal functions, and between goal functions. (C) 2003 Elsevier B.V. All rights reserved.

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Deterioration of concrete or reinforcing steel through excessive contaminant concentration is often the result of repeated wetting and drying cycles. At each cycle, the absorption of water carries new contaminants into the unsaturated concrete. Nuclear Magnetic Resonance (NMR) is used with large concrete samples to observe the shape of the wetting profile during a simple one-dimensional wetting process. The absorption of water by dry concrete is modelled by a nonlinear diffusion equation with the unsaturated hydraulic diffusivity being a strongly nonlinear function of the moisture content. Exponential and power functions are used for the hydraulic diffusivity and corresponding solutions of the diffusion equation adequately predict the shape of the experimental wetting profile. The shape parameters, describing the wetting profile, vary little between different blends and are relatively insensitive to subsequent re-wetting experiments allowing universal parameters to be suggested for these concretes.

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Background/Aims: Host factors such as increased body mass index (BMI) and genotype-specific viral factors contribute to the development of steatosis in patients with chronic hepatitis C (HCV). We hypothesized that host metabolic factors associated with increased BMI may play a role in disease progression. Methods: Fasting serum was collected from 160 patients with chronic HCV at the time of liver biopsy and 45 age, gender and BMI matched controls, and assessed for levels of insulin, c-peptide and leptin. Results: Patients with viral genotype 3 had more severe steatosis (P = 0.0001) and developed stages 1 and 2 fibrosis at a younger age (P < 0.05) than patients with genotype 1. For both genotypes, overweight patients had significantly more steatosis and increased insulin and leptin levels. In contrast to lean patients, there was a statistically significant increase in circulating insulin levels with increasing fibrosis in overweight patients with chronic HCV (P = 0.03). Following multivariate analysis, insulin was independently associated with fibrosis (P = 0.046) but not inflammation (P = 0.83). There was no association between serum leptin levels and stage of fibrosis. Conclusions: Increasing circulating insulin levels may be a factor responsible for the association between BMI and fibrosis in patients with HCV, irrespective of viral genotype. (C) 2003 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

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Although obesity is associated with increased risks of morbidity and death in the general population, a number of studies of patients undergoing hemodialysis have demonstrated that increasing body mass index (BMI) is correlated with decreased mortality risk. Whether this association holds true among patients treated with peritoneal dialysis (PD) has been less well studied. The aim of this investigation was to examine the association between BMI and outcomes among new PD patients in a large cohort, with long-term follow-up monitoring. Using data from the Australia and New Zealand Dialysis and Transplant Registry, an analysis of all new adult patients (n = 9679) who underwent an episode of PD treatment in Australia or New Zealand between April 1, 1991, and March 31, 2002, was performed. Patients were classified as obese (BMI of greater than or equal to30 kg/m(2)), overweight (BMI of 25.0 to 29.9 kg/m(2)), normal weight (BMI of 20 to 24.9 kg/m(2)), or underweight (BMI of

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Adolescents and adults with CF have lower bone mineral density (BMD) than normal, but its relationship with phenotype is not well understood. Point FEV1% predicted (FEV) and rate of change of FEV are biased estimates of disease severity, because progressively older subjects represent a selected survivor population, with females at greater risk of death than males. To investigate the relationship between BMD and phenotype we used an index (predicted age at death) derived from Bayesian estimates of slope and intercept of FEV, age at last measurement and survival status. Predictive equations for the index were derived from 97 subjects (78 survivors) from the RCH CF clinic, and applied to a group of 102 comparable subjects who had BMD measured, classified as having‘mild’ ()75th), ‘moderate’ (25– 75th), or ‘severe’ (-25th centile) phenotype. Total body (TB) and lumbar spine (LS) BMD z-scores (Z) were compared, adjustingfor gender effects, using 2-way ANOVA. Annual mean change in FEV segregated, as expected, according to phenotype, ‘severe’ (ns25), ‘moderate’ (ns51) and ‘mild’ (ns25) y3.01(y3.73 to y2.30)%, y0.85(y1.36 to y0.35)%, 2.70(1.92 to 3.46)%, respectively, with no gender difference. LS and TB BMDZ were different in each phenotype (P-s 0.002), LS BMDZ for ‘severe’, ‘moderate’ and ‘mild’ y1.63(CI: y2.07 to y 1.19), y0.86(CI: y1.17 to y0.55), y0.06(CI: y0.54 to 0.41). Males had lower LS BMDZ than females overall (y1.22 (CI: y1.54 to y0.91) vs. y0.48(CI: y 0.84 to y0.12) Ps0.002). In the ‘severe’ group, males had lower TB BMDZ and LS BMDZ (PF0.002). Low BMD is associated with ‘moderate’ and ‘severe’ phenotypes, with relative preservation in females in the ‘severe’ group. Female biology (reproductive fitness) might promote resistance to bone resorption at a critical level of BMD loss.

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In this paper we present a technique for visualising hierarchical and symmetric, multimodal fitness functions that have been investigated in the evolutionary computation literature. The focus of this technique is on landscapes in moderate-dimensional, binary spaces (i.e., fitness functions defined over {0, 1}(n), for n less than or equal to 16). The visualisation approach involves an unfolding of the hyperspace into a two-dimensional graph, whose layout represents the topology of the space using a recursive relationship, and whose shading defines the shape of the cost surface defined on the space. Using this technique we present case-study explorations of three fitness functions: royal road, hierarchical-if-and-only-if (H-IFF), and hierarchically decomposable functions (HDF). The visualisation approach provides an insight into the properties of these functions, particularly with respect to the size and shape of the basins of attraction around each of the local optima.

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Trabalho realizado durante a vigência de bolsa de produtividade em pesquisa/CNPq.

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A pesquisa busca mostrar como o discurso religioso do gênero sermão, na voz do enunciador Frei Gregório José Maria de Bene, pode influir na estratégia de adesão e convencimento dos escravos da região de Serra, província do Espírito Santo, para a construção da igreja do Queimado. O sermão citado é o recorte fundamental do discurso literário O Templo e a Forca (1999), recriado por Luiz Guilherme Santos Neves, analisado a partir de cena englobante legitimadora. O trabalho insere-se nos estudos da Analise do Discurso (AD) de linha francesa, pelo referencial teórico de Dominique Maingueneau, que nos orientará quanto às cenografias do padre, sua imagem de enunciador, as condições de produção do sermão, ressaltando elementos que interagem no embate, visando à sociedade da época e às questões culturais dos envolvidos na eclosão da revolta. O principal objetivo é examinar as cenas de enunciação e como se constrói o ethos religioso em cada cena e suas variadas funções. É elementar dizer que o religioso se reconstrói a cada momento a partir do comprometimento com as situações de comunicação. Para maior entendi-mento, dizemos que essas diversas reconstruções apresentam nos discursos diferentes encenações desse tão fomentado religioso com suas estratégias de adesão, apresentando-se ora com a imagem daquele que fala em nome de Deus, preza a docilidade da vida do campo à sombra das andirobeiras gigantes onde se pode sentir o silêncio que convida à contemplação e à prece; ora aquele comprometido com seus propósitos interesseiros e pessoais. Fala para não ser entendido, e o que vale é erguer a casa de São José sem poupar a carne e o sangue das mortes que virão. Importa ressaltar que sempre há possibilidade de olhar ingênuo sobre texto religioso, que, conforme Main-gueneau (2010), só é legível relacionado a vasto intertexto que contribuirá para estruturar o discurso. Para enriquecer ainda mais este estudo, afora o gênero sermão usamos recortes que estruturam o discurso de Neves e sinalizam as variadas cenografias e a forma como se constituem enquanto gêneros: Diálogo interior – momentos solitários do frade – Visão do frade e Monólogo; Diálogo Compartilhado – segmenta diálogos entre o enunciador e seus vários co-enunciadores, que estruturam os acontecimentos do discurso; e o gênero exortação, do padre aos escravos. Os recortes são momentos de grandes embates recriados pelo autor, em discurso leve fazendo seu leitor transitar prazerosamente junto ao frade entre as suas variadas imagens nos discursos. Levando o leitor a acreditar tratar-se de cenas relacionadas ao gênero cômico. E talvez o fosse, se não terminasse em revolta.

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In the last decade, population ageing has been registered as a global phenomenon. A relation exists between falling and ageing, since falling frequency increases significantly with age. In fact, one in three older adult falls annually. Although ageing is generically associated with decrease and degeneration of psychological and physical functions, it is still not common for the correct identification of risk factors to lead to a clinical prognosis of the elder being in risk of falling. Therefore, the goal of this review article is to identify, categorise and analyse typical ageing and fall factors mentioned in the literature as well as to quantify the number of times they were referenced. The research considered hundreds of publications, but analysis was then restricted to the 87 most pertinent articles written in English and published in journals or scientific magazines between 1995 and 2010. We concluded that falls among older adults can be characterised by the following: anatomic characteristics and physiological consequences of ageing; the pathologies that induce falls, which can be neurological, musculoskeletal, cardiovascular and other diseases; causes and risk factors of falls that can be behavioural, biological, environmental or socio-economic; type of physical consequences of falls, including fractures, bruises, injuries or other physical consequences; and strategies to prevent, mitigate or rehabilitate, which can be of a physical, environmental or behavioural nature.

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In the last decade, population ageing has been registered as a global phenomenon. A relation exists between falling and ageing, since falling frequency increases significantly with age. In fact, one in three older adult falls annually. Although ageing is generically associated with decrease and degeneration of psychological and physical functions, it is still not common for the correct identification of risk factors to lead to a clinical prognosis of the elder being in risk of falling. Therefore, the goal of this review article is to identify, categorise and analyse typical ageing and fall factors mentioned in the literature as well as to quantify the number of times they were referenced. The research considered hundreds of publications, but analysis was then restricted to the 87 most pertinent articles written in English and published in journals or scientific magazines between 1995 and 2010. We concluded that falls among older adults can be characterised by the following: anatomic characteristics and physiological consequences of ageing; the pathologies that induce falls, which can be neurological, musculoskeletal, cardiovascular and other diseases; causes and risk factors of falls that can be behavioural, biological, environmental or socio-economic; type of physical consequences of falls, including fractures, bruises, injuries or other physical consequences; and strategies to prevent, mitigate or rehabilitate, which can be of a physical, environmental or behavioural nature.

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The purpose of this study is to characterize how Portuguese Small and Medium Enterprises (SMEs) view the Occupational Health and Safety Management Systems (OHSMSs) certification process, after receiving the Quality Management System (QMS) certification. References were based on the ISO 9001 standard for a QMS and OHSAS 18001 for OHSMS. The method used to evaluate the implemented systems, was by form of questionnaire. Those questioned had to have a certified quality management system, an implemented OHSMS and be a SME. The questionnaire was sent to 300 SMEs; 46 responses were received and validated. Of them, only 12 SMEs had the OHSMS certificate according to OHSAS 18001. Within those 12 companies that participated: 7 SMEs are from the industrial sector; 3 belong to the electricity/telecommunications sector and 2 SMEs are from the trade/services activity sector. The size of the sample was small, but corresponds to Portuguese reality. Moreover, 34 SMEs did not have the OHSMS certificate. The questionnaire requested the main reasons for SMEs to opt for non-certification and it was related with high costs, while the main reasons to certificate were, among others, needed to eliminate or minimize risks to workers. The main benefits that Portuguese SMEs have gained from the referred certifications have been, improved working conditions, ensuring compliance with legislation and better internal communication about risks and hazards. Also presented are the main difficulties in achieving an OHSMS certification including high certification costs, difficulties motivating personnel, difficulties in changing the company’s culture and increased bureaucracy.

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The biological nitrogen fixation is an alternative to supply the nitrogen needed for maize. The objective of this study was to evaluate the development and yield of maize in response to inoculation with Azospirillum associated with nitrogen fertilization. We conducted two field experiments in the summer harvest, the first in the 2000/2001 crop year in the region of Marechal Cândido Rondon, under conventional tillage, and second in the 2002/2003 agricultural year in the region of Cascavel, under no tillage. The experimental design in both experiments was a randomized complete block, with four replications, 2x2x2 factorial, with two levels of nitrogen at sowing (zero and 20 kg ha-1), two levels of inoculum (zero and 200 g ha-1) and two levels of nitrogen in topdressing (zero and 100 kg ha-1). There was evaluated the height of ear insertion, total plant height, leaf N content, shoot dry biomass and grain yield. The height of ear insertion and total plant height were not influenced by the factors under study. Nitrogen fertilization at sowing increased the leaf N content, causing the opposite effect when combined with inoculation. Inoculation with Azospirillum in the absence of nitrogen, provide productivity increases of 15.4% and 7.4% for 2000/2001 and 2002/2003 crops, respectively. The inoculation provided productivity similar to that obtained with 100 kg ha-1 in topdressing in crop 2000/2001, while in association with the topdressing, reduced productivity and shoot dry biomass in crop 2002/2003.

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Education for health is a process in which all public health and medical care personnel are involved. People learn both formally (planned learning experiences) and informally (unplanned learning experiences). Since the patient, the client, the consummer and the community expect public health and medical care personnel to assist them with health and disease issues and problems, the response of the professional "educates" the customer whether the professional intends to educate or not. Therefore, it is incumbent on all public health and medical care professionals to understand their educational functions and their role in health education. It is also important that the role of the specialist in education be clear. The specialist, as to all other specialists, has an in-depth knowledge of his area of expertise, i.e., the teaching/learning process; s/he may function as a consultant to others to enhance the educational potential of their role or s/he may work with a team or with communities or groups of patients. Specific competencies and knowledge are required of the health education specialist; and there is a body of learning and social change theory which provides a frame of reference for planning, implementing and evaluating educational programs. Working with others to enhance their potential to learn and to make informed decisions about health/disease issues is the hallmark of the health education specialist.