812 resultados para Population data


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The wood mouse is a common and abundant species in agricultural landscape and is a focal species in pesticide risk assessment. Empirical studies on the ecology of the wood mouse have provided sufficient information for the species to be modelled mechanistically. An individual-based model was constructed to explicitly represent the locations and movement patterns of individual mice. This together with the schedule of pesticide application allows prediction of the risk to the population from pesticide exposure. The model included life-history traits of wood mice as well as typical landscape dynamics in agricultural farmland in the UK. The model obtains a good fit to the available population data and is fit for risk assessment purposes. It can help identify spatio-temporal situations with the largest potential risk of exposure and enables extrapolation from individual-level endpoints to population-level effects. Largest risk of exposure to pesticides was found when good crop growth in the “sink” fields coincided with high “source” population densities in the hedgerows. Keywords: Population dynamics, Pesticides, Ecological risk assessment, Habitat choice, Agent-based model, NetLogo

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Earthworms are important organisms in soil communities and so are used as model organisms in environmental risk assessments of chemicals. However current risk assessments of soil invertebrates are based on short-term laboratory studies, of limited ecological relevance, supplemented if necessary by site-specific field trials, which sometimes are challenging to apply across the whole agricultural landscape. Here, we investigate whether population responses to environmental stressors and pesticide exposure can be accurately predicted by combining energy budget and agent-based models (ABMs), based on knowledge of how individuals respond to their local circumstances. A simple energy budget model was implemented within each earthworm Eisenia fetida in the ABM, based on a priori parameter estimates. From broadly accepted physiological principles, simple algorithms specify how energy acquisition and expenditure drive life cycle processes. Each individual allocates energy between maintenance, growth and/or reproduction under varying conditions of food density, soil temperature and soil moisture. When simulating published experiments, good model fits were obtained to experimental data on individual growth, reproduction and starvation. Using the energy budget model as a platform we developed methods to identify which of the physiological parameters in the energy budget model (rates of ingestion, maintenance, growth or reproduction) are primarily affected by pesticide applications, producing four hypotheses about how toxicity acts. We tested these hypotheses by comparing model outputs with published toxicity data on the effects of copper oxychloride and chlorpyrifos on E. fetida. Both growth and reproduction were directly affected in experiments in which sufficient food was provided, whilst maintenance was targeted under food limitation. Although we only incorporate toxic effects at the individual level we show how ABMs can readily extrapolate to larger scales by providing good model fits to field population data. The ability of the presented model to fit the available field and laboratory data for E. fetida demonstrates the promise of the agent-based approach in ecology, by showing how biological knowledge can be used to make ecological inferences. Further work is required to extend the approach to populations of more ecologically relevant species studied at the field scale. Such a model could help extrapolate from laboratory to field conditions and from one set of field conditions to another or from species to species.

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Children with an autism spectrum disorder (ASD) may be vulnerable to social isolation and bullying. We measured the friendship, fighting/bullying and victimization experiences of 10–12-year-old children with an ASD (N = 100) using parent, teacher and child self-report. Parent and teacher reports were compared to an IQ-matched group of children with special educational needs (SEN) without ASD (N = 80) and UK population data. Parents and teachers reported a lower prevalence of friendships compared to population norms and to children with SEN without an ASD. Parents but not teachers reported higher levels of victimization than the SEN group. Half of the children with an ASD reported having friendships that involved mutuality. By teacher report children with an ASD who were less socially impaired in mainstream school experienced higher levels of victimization than more socially impaired children; whereas for more socially impaired children victimization did not vary by school placement. Strategies are required to support and improve the social interaction skills of children with an ASD, to enable them to develop and maintain meaningful peer friendships and avoid victimization.

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Objective. Estimate cataract surgical rates (CSR) for Brazil and each federal unit in 2006 and 2007 based on the number of surgeries performed by the Unified Health System to help plan a comprehensive ophthalmology network in order to eliminate cataract blindness in compliance with the target set by the World Health Organization (WHO) of 3 000 cataract surgeries per million inhabitants per year. Methods. This descriptive study calculates CSR by using the number of cataract surgeries carried out by the Brazilian Unified Health System for each federal unit and estimates the need for cataract surgery in Brazil for 2006-2007, with official population data provided by the Brazilian Institute of Geography and Statistics. The number of cataract surgeries was compared with the WHO target. Results. To reach the WHO goal for eliminating age-related cataract blindness in Brazil, 560 312 cataract surgeries in 2006 and 568 006 surgeries in 2007 needed to be done. In 2006, 179 121 cataract surgeries were done by the Unified Health System, corresponding to a CSR of 959 per million population; in 2007, 223 317 were performed, with a CSR of 1 179. With the Brazilian Council of Ophthalmology estimation of 165 000 surgeries each year by the non-public services, the CSR for Brazil would be 1 842 for 2006 and 2 051 for 2007. The proportions needed to achieve the proposed target were 38.6% in 2006 and 31.6% in 2007. Conclusions. Human resources, technical expertise, and equipment are crucial to reach the WHO goal. Brazil has enough ophthalmologists but needs improved planning and infrastructure in order to eliminate the problem, aspects that require greater financial investment and stronger political commitment.

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The problems of finding best facility locations require complete and accurate road network with the corresponding population data in a specific area. However the data obtained in road network databases usually do not fit in this usage. In this paper we propose our procedure of converting the road network database to a road graph which could be used in localization problems. The road network data come from the National road data base in Sweden. The graph derived is cleaned, and reduced to a suitable level for localization problems. The population points are also processed in ordered to match with that graph. The reduction of the graph is done maintaining most of the accuracy for distance measures in the network.

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Unemployment as an unintended consequence of social assistance recipiency: results from a time-series analysis of aggregated population data Does the frequency of unemployment have a tendency to increase the number of social assistance recipients, or does the relationship work the other way around? This article utilizes Swedish annual data on aggregated unemployment and means-tested social assistance recipiency in the period 1946–1990 and proposes a multiple time-series approach based on vector error-correction modelling to establish the direction of influence. First, we show that rates of unemployment and receipt of social assistance is co-integrated. Second, we demonstrate that adjustments to the long-run equilibrium are made through adjustments of the unemployment. This indicates that the level of unemployment reacts to changes in rates of social assistance recipiency rather than vice versa. It is also shown that lagged changes in the level of unemployment do not predict changes in rates of social assistance recipients in short-term. Together these findings demonstrate that the number of social assistance recipients does increase the number of unemployed in a period characterized by low unemployment and high employment.

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Os efeitos provocados por radiações são conhecidos na literatura por meio dos estudos em usinas nucleares e em testes bélicos. Entretanto, os efeitos da radiação natural vêm despertando a atenção das autoridades da saúde, dentre as quais se destaca a Environmental Protection Agency (EPA) nos Estados Unidos e a National Radiological Protection Board (NRPB) no Reino Unido. Os efeitos epidemiológicos ocasionados por radiação de origem natural, mais especificamente a radiação emanada pelo gás radônio que fica acumulado em residências enclausuradas por muito tempo, tem sido alvo de intensas investigações. Nessa dissertação, foi realizada uma avaliação ambiental preliminar da radiação natural devida ao radônio como elemento epidemiológico no Escudo Sul-riograndense. Os dados utilizados para determinar o risco epidemiológico foram: neoplasias, radiação, geologia e população. O banco de dados dos casos de óbitos por neoplasias do estado foi obtido da Secretaria da Saúde, por meio do Núcleo de Informação em Saúde. A radiação natural devida ao radônio foi determinada a partir dos dados gamaespectrométricos obtidos de levantamento aerogeofísico da CPRM no Escudo Sul-riograndense, nos projetos Camaquã e Extremo Sudeste do Brasil realizados nos anos de 1973 e 1978, respectivamente. Os dados geológicos foram obtidos do Mapa Geológico do Estado de 1989. Os dados de população foram obtidos junto ao Instituto Brasileiro de Geografia e Estatística (IBGE). A integração de dados foi realizada usando a metodologia de matriz de sobreposição entre os dados de casos de óbitos por neoplasia e de gamaespectrometria. Os dados de população foram empregados para normalizar os dados de neoplasias, e o dado de geologia para correlacionar com a gamaespectrometria. Os resultados da integração são mapas classificados pelo grau de risco epidemiológico, nos quais é apresentada a relação entre os casos de neoplasias pela intensidade de radiação devida ao radônio. Nesse sentido, uma boa relação foi assinalada e são recomendados estudos adicionais sobre esse mesmo banco de dados.

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Este trabalho teve o prof5sito de utilizar o Modelo de Likert (mensuração das variáveis causais, intervenientes e de resultado) nos Departamentos da Universidade Federal do Espirito Santo. Esta iniciativa decorreu da intenção de obter o perfil administrativo dos Departamentos, bem como de seu respectivo desempenho (mensuração das variáveis de resultado). De posse das mensurações dos três grupos de variáveis (causais, intervenientes e de resultado), pôde-se efetuar comparações dos 50 Departamentos objeto de pesquisa. preliminarmente, procurou-se de maneira bastante abrangente enfatizar o estudo, seus objetivos, importância e, finalmente, a organização do trabalho (Capitulo 1). Na segunda etapa, proporcionou-se uma ampla visão da teoria organizacional, procurando salientar as quatro grandes correntes. A seguir, apresentou-se o Modelo de Likert com todas as suas especificidades (Capitulo 2). Com relação a terceira etapa, foi estabelecida toda a operacionalização do trabalho, iniciando com a definição da população e amostra, passando pela coleta de da- \ dos, trabalho de campo, análise dos dados e, finalmente, enfatizando as inúmeras limitações da pesquisa (Capitulo 3). No tocante a quarta etapa, antes de iniciar a apresentação e análise dos resultados, fez-se uma retrospectiva histórica da estrutura da Universidade Federal do Espirito Santo, com o intuito de buscar suas origens e facilitar o entendimento da análise (Capítulo 4). Finalmente, na quinta etapa, procurou-se registrar todos os pontos conclusivos decorrentes da utilização do Modelo de Likert junto aos Departamentos da Universidade Federal do Espírito Santo. Neste capitulo, ficou evidenciada, sobretudo, a necessidade de a Universidade procurar otimizar seus recursos (Capítulo 5).

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OBJETIVO: Apresentar revisão de literatura sobre o uso do copo/xícara como método alternativo de alimentação para recém-nascidos prematuros e verificar se há consenso sobre sua indicação para essa população. FONTES DE DADOS: Revisão de literatura narrativa, tendo sido selecionados artigos nas bases de dados Medline, Lilacs, SciELO e Cochrane, independentemente do ano, usando descritores específicos: alimentação artificial, recém-nascido prematuro, aleitamento materno, métodos de alimentação. SÍNTESE DOS DADOS: Apesar de alguns estudos afirmarem que o método do copo/xícara é eficaz e seguro para alimentar recém-nascidos pré-termo e a termo, tais estudos não avaliam de forma objetiva o efeito do método sobre a deglutição desses pacientes. CONCLUSÕES: Verificou-se não haver consenso na literatura quanto à complementação da alimentação de recém-nascidos prematuros por meio do copo/xícara. Estudos controlados devem ser realizados com a finalidade de rever riscos e benefícios do uso de métodos alternativos na alimentação do recém-nascido prematuro.

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Considerando o Diabetes mellitus (DM) como um relevante problema de saúde no Brasil e a importância das estimativas de prevalência para planejamento e estratégias em saúde pública, propôs-se este trabalho com o objetivo de estimar a razão de prevalências do DM nos diferentes estados brasileiros nos períodos de 2002 a 2004 e 2005 a 2007. Trata-se de estudo descritivo, baseado em dados da população brasileira com diagnóstico de DM cadastrada no Sistema de Informação da Atenção Básica (SIAB) junto ao Ministério da Saúde. As taxas de prevalência foram calculadas para o período de 2002 a 2004 e para 2005 a 2007, e posteriormente estimou-se a Razão de Prevalências (R) por ponto e por intervalo de 95% de confiança (IC95%). Observou-se alta prevalência de DM nos estados brasileiros com aumento significativo (R>1; IC95%>1) entre os períodos em todos os estados brasileiros, com destaque para o Distrito Federal (R=1,9800; IC95%=1,97241,9876) e o estado do Maranhão (R=1,5217; IC95%=1,51981,5235). Pode-se concluir que houve aumento significativo na prevalência de DM no Brasil de 2002 a 2007, sinalizando para a necessidade de formulação de estratégias de prevenção e controle da doença.

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

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The relative contribution of migration of Rhizoctonia solani anastomosis group 3 (AG-3) on infested potato seed tubers originating from production areas in Canada, Maine, and Wisconsin (source population) to the genetic diversity and structure of populations of R. solani AG-3 in North Carolina (NC) soil (recipient population) was examined. The frequency of alleles detected by multilocus polymerase chain reaction-restriction fragment length polymorphisms, heterozygosity at individual loci, and gametic phase disequilibrium between all pairs of loci were determined for subpopulations of R. solani AG-3 from eight sources of potato seed tubers and from five soils in NC. Analysis of molecular variation revealed little variation between seed source and NC recipient soil populations or between subpopulations within each region. Analysis of population data with a Bayesian-based statistical method previously developed for detecting migration in human populations suggested that six multilocus genotypes from the NC soil population had a statistically significant probability of being migrants from the northern source population. The one-way (unidirectional) migration of genotypes of R. solani AG-3 into NC on infested potato seed tubers from Canada, Maine, and Wisconsin provides a plausible explanation for the lack of genetic subdivision (differentiation) between populations of the pathogen in NC soils or between the northern source and the NC recipient soil populations.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Doenças Tropicais - FMB