1,287 research outputs found
A Multi-Criteria Approach for Irrigation Water Management
The major implications that the European Union (EU) Water Framework Directive (WFD) may have in irrigated agriculture were analysed using alternative water policy measures. The consequences of policy change were evaluated in a case study (Baixo Alentejo, Portugal), using a Multi-Criteria Decision Making (MCDM) model that simulates farmers’ preferred behaviour. The study compares the effects of water pricing (volumetric and flat tariffs) and consumption quotas, in farmer’s income, water agency revenues, agricultural employment and water demand for irrigation. Model results indicate that the adjustments in farmer’s responses are dependent on the policy strategy enforced and on the policy level.Water Framework Directive, Flat Pricing, Volumetric Pricing, Multi- Objective Programming, Water Management, Portugal,
Prediction of maximum oxygen uptake from a modified Ymca 3-minute step test
The relationship between post exercise recovery heart rate (PERHR) and maximum oxygen uptake using a height specific bench with a modified Young Men\u27s Christian Association (YMCA) 3-Minute Step Test was investigated. Sixty apparently healthy males and females between the ages of 18 and 55 years stepped on a height specific bench for 3 minutes in order to obtain their 1-minute and 15-second post exercise recovery heart rates. An EKG monitored post exercise recovery heart rates. Maximum oxygen uptake was measured by open circuit spirometry on a motor-driven treadmill. Correlation and regression statistics were used to analyze the data. Results indicate a significant correlation between the 1-minute PERHR and maximum oxygen uptake (r =.5796, r{dollar}\sb{\rm critical}{dollar} =.2108) and a significant correlation between the 15-second PERHR and maximum oxygen uptake (r =.5428, r{dollar}\sb{\rm critical}{dollar} =.2108)
El espejismo de las dos culturas
El 8 de mayo de 1794, tres meses antes de la caída de Robespierre, Lavoisier fue decapitado. La sentencia se ejecutó tras denegarle el aplazamiento solicitado para terminar unos experimentos que de otro modo
quedarían inconclusos. La respuesta que recibió del tribunal de apelación fue sumaria: "La République n'a pas besoin de savants". ¡Que grandiosa estupidez! Desde entonces disponemos de un hermoso símbolo para reflexionar sobre las difíciles relaciones históricas entre las dos repúblicas, la de los sabios y la de los políticos.
A patir de esta experiencia, se identifican otros casos, antiguos y modernos, que permiten una reflexión sobre el mito de las dos culturas.Peer reviewe
Effectiveness of COVID-19 Vaccines: Evidence from the First-Year Rollout of Vaccination Programs
Antonio, N., Rita, P., & Saraiva, P. (2022). Effectiveness of COVID-19 Vaccines: Evidence from the First-Year Rollout of Vaccination Programs. Vaccines, 10(3), 1-19. [409]. https://doi.org/10.3390/vaccines10030409 ---------------- The work by Nuno António, Paulo Rita, and Pedro Saraiva was supported by Fundação para a Ciência e a Tecnologia (FCT) within the Project: UIDB/04152/2020-Centro de Investigação em Gestão de Informação (MagIC).The COVID-19 pandemic has raised a number of new realities, sets of data, and opportunities for data-driven approaches, decisions, and conclusions. One particular area for which developments and data have been made available in record time is related to vaccines and their impacts on health conditions and saving lives. In this article, we use public domain information to study the prevalence of vaccines in different countries and how they can save lives. We conclude that there are different clusters of countries, for some of which solid statistical models were built, and show that vaccination rates provide significant contributions to saving lives in such countries, with impacts that can be computed by simulations based upon these models.publishersversionpublishe
Laboratory activities and physics learning at high school: an exploratory study in portuguese settings
In this paper we present findings of an exploratory study, included in a wider investigation which intends to promote meaningful learning of physics concepts, based on experimental work and supported by metacognition tools. The aim of this research was to recognize promoting learning situations in Physics lab. Interviews and questionnaires were applied to teachers and students from four Lisbon high schools. Results show that lab work in physics has a low frequency and, generally, has a demonstration format. Both teachers and students recognize potentialities of lab work to promote learning. Learning is poor when students just observe and/or accomplish commands. Both teachers and students consider the relation theory/experimentation and students doing themselves as fundamental to achieve better learning. In addition to pointing out several problems concerning lab work, teachers envisage it in a very traditional way. So, innovative strategies and methodologies, such as computer use and open-ended problems, pointed by research in science investigation as promoting learning, are left aside
A Estratégia de Qualidade “LARG” na rede de abastecimento da Indústria Automóvel como uma rede de Cooperação
A estrutura, organização, integração e coordenação das redes de abastecimento
são fundamentais para melhorar o desempenho global e ajudá-las a alcançar os
seus objetivos estratégicos e operacionais. A literatura sugere que as cadeias de
abastecimento eficientes, ágeis, resilientes e sustentáveis se adaptam melhor ao
cenário dinâmico e instável sendo mais competitivas.
Este artigo tem como objetivo apresentar um modelo para a implementação de
uma estratégia de qualidade baseada nos paradigmas: (L)ean, (A)gilidade,
(R)esiliência e (G)reen – sustentabilidade ambiental), cujas iniciais irão formar o
acrónimo “LARG”, usado para mais facilmente designar a estratégia adequada à
extrema competitividade que caracteriza a indústria automóvel.
Usando uma "abordagem construção de teoria", apoiada por um estudo de caso,
realizado em quatro empresas que integram a rede de abastecimento da indústria
automóvel, foram definidas as questões de pesquisa e proposto um modelo
conceptual e uma metodologia de aplicação do mesmo.
Este estudo contribui para a literatura, por empiricamente investigar os princípios
que devem nortear a implementação da estratégia de qualidade “LARG”, assim
como a estruturação e o desempenho da rede de abastecimento, propondo uma
abordagem por processos aplicada a uma estrutura em rede virtual, com o objetivo
de melhorar a eficiência da rede. A análise dos dados suporta algumas conclusões
interessantes como a sugestão de mudar a designação da cadeia de abastecimento
para rede de abastecimento
Esquemas interpretativos e estratégias institucionais : estudo de caso em um sistema de cooperativas de crédito
Orientador : Prof. Dr. João Marcelo CrubellateDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Sociais Aplicadas, Programa de Pós-Graduação em Administração. Defesa: Curitiba, 30/03/2010Bibliografia: fls. 120-123Área de concentração: Estratégia e OrganizaçõesResumo: O presente trabalho procurou descrever e analisar as mudanças ocorridas nos esquemas interpretativos predominantes na Cooperativa Central de Crédito do Paraná – Central Sicredi PR durante o período de 1995 a 2008, bem como investigar as relações existentes entre tais mudanças e as estratégias institucionais implementadas ou apoiadas por aquela cooperativa central no mesmo período. O campo da pesquisa foi escolhido em razão da observação de que o cooperativismo de crédito é um setor da economia que tem apresentado significativo crescimento e uma história recente repleta de mudanças, tanto de características técnicas quanto institucionais. Por isso, o estudo partiu da premissa de que o desenvolvimento das cooperativas de crédito tem sido positivamente influenciado por mudanças nas regras institucionais do setor e visou investigar a agência das próprias cooperativas nesse processo de mudança institucional. Trata-se de um estudo de natureza qualitativa-descritiva, baseado em conceitos desenvolvidos no ramo sociológico da teoria institucional e na noção de interação recíproca entre agência e estrutura. A estratégia de pesquisa foi a de estudo de caso único com uma perspectiva de corte seccional, porém com características longitudinais, considerando o levantamento de dados históricos. O nível de análise foi o organizacional e a unidade de análise foram os dirigentes que compunham o Conselho de Administração da Central Sicredi PR. As técnicas de tratamento dos dados foram a análise de conteúdo e a elaboração de mapas cognitivos. A análise de conteúdo foi qualitativa e a unidade de significação foi o tema. A coleta e o tratamento dos dados foram realizados em três etapas, sendo as duas primeiras relativas à coleta de dados documentais e a terceira referente a entrevistas com gestores, escolhidos em razão de seu envolvimento com as estratégias institucionais identificadas. O principal resultado alcançado foi a caracterização de uma relação de reciprocidade entre as mudanças na visão de mundo dos dirigentes e a implementação das estratégias institucionais, em um processo cujo resultado foi a construção de uma nova identidade organizacional, carregada de valores e interesses emprestados da lógica corporativa do mercado financeiro e focada no desenvolvimento do próprio sistema.Abstract: The objective of this study was to describe and analyse the changes occurred at the prevalent interpretive schemes in a Brazilian Credit Cooperative Federation . Central Sicredi PR - between 1995 and 2008, and to investigate the relations between those changes and the institutional strategies implemented by that Federation during the same period. This research field was chosen because the credit cooperative segment has shown a significant growth and has recently undergone through many changes on its technical and institutional characteristics. Therefore, this study took the premise that the development of credit cooperatives has been positively influenced by changes occurred in the institutional rules and aimed to investigate the credit cooperative agency in this process. It is a qualitative descriptive study based on concepts developed in the sociological branch of institutional theory, as well as the notion of reciprocal interaction between agency and structure. The single case study research strategy was chosen. The perspective was a cross sectional with longitudinal characteristics, considering the historical data collection. The organizational level of analysis was used and the unit of analysis was the members of the Board of Directors of Central Sicredi PR. The content analysis and construction of cognitive maps were the techniques used to process the data. Content analysis was qualitative, using subject as the unit of meaning. Data were collected and processed in three stages: the first two stages relating to the collection of documentary data and the third relating to interviews with managers chosen due to their involvement with institutional strategies. The main result achieved was the characterization of a reciprocal relationship between changes in the leaders. worldview and the implementation of institutional strategies, in a process that resulted in the building of a new organizational identity, full of interests and values borrowed from the business logic of the financial market and focused on the development of the federation itself
Modeling boron adsorption on five soils before and after removal of organic matter
Boron-B concentrations that cause deficiency and those that cause toxicity appear to be very similar, compared to other nutrients, which can complicate successful management of this element in soils. In this study, B adsorption onto two Oxisols from Brazil (Rhodic Eutroperox and Anionic Acroperox), two Alfisols (Natric Palexeralf and Aridic Paleustalf) and an Entisol (Xeric Torrifluvent) from the United States of America were evaluated. The samples were treated with sodium hypochlorite in order to remove soil organic matter. Both treated and untreated samples were used to determine B adsorption isotherms using different B concentrations (0- 4.630 mmol L–1) and NaNO3 (0.05 M) as background electrolyte solution at pH 7. Boron adsorption envelopes were also measured using 0.463 mmol L–1 B at three ionic strengths (0.05, 0.1 and 1M) and NaNO3 as background electrolyte solutions at different pH values (3-12). The cation exchange capacity, specific surface area, free Al and Fe oxides, organic and inorganic carbon content, mineralogy and particle size distribution of the soils were also determined. The Langmuir isotherm and the constant capacitance model were fit to the B adsorption data and the parameters obtained were related to the chemical attributes by multiple linear regression equations. Boron maximum adsorption capacity (BMAC) and the complexation constant for the SH3BO4 – inner-sphere complex (LogKB–) could be predicted under all experimental conditions. The Alc content was the main soil chemical attribute associated with the BMAC under the conditions evaluated and the LogKB–(int) in untreated and treated samples
Maltitol:Analytical Determination Methods, Applications in the Food Industry, Metabolism and Health Impacts
Bulk sweetener maltitol belongs to the polyols family and there have been several dietary applications in the past few years, during which the food industry has used it in many food products: bakery and dairy products, chocolate, sweets. This review paper addresses and discusses in detail the most relevant aspects concerning the analytical methods employed to determine maltitol’s food safety and industry applications, its metabolism and its impacts on human health. According to our main research outcome, we can assume that maltitol at lower doses poses little risk to humans and is a good alternative to using sucrose. However, it causes diarrhoea and foetus complications at high doses. Regarding its determination, high-performance liquid chromatography proved the primary method in various food matrices. The future role of maltitol in the food industry is likely to become more relevant as processors seek alternative sweeteners in product formulation without compromising health
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