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- O comprometimento organizacional e o bem-estar dos colaboradores ao longo da vida : um estudo empíricoPublication . Sousa, Áurea; Mota, Vera; Batista, Maria Da Graça[…]. A presente investigação tem como principal objetivo relacionar o bem-estar subjetivo dos colaboradores com o comprometimento organizacional com base num estudo empírico. […]. Os trabalhadores da amostra global percecionam níveis satisfatórios de auto-comprometimento organizacional global, sendo de salientar, ainda, a existência de uma relação entre o comprometimento organizacional dos colaboradores e o seu bem-estar subjetivo. A aplicação do método das k-médias, […], permitiu detetar três grupos de indivíduos, de acordo com as pontuações obtidas nas escalas que avaliam o bem-estar subjetivo, sendo de ressaltar que os indivíduos nos diferentes clusters auto-percecionaram diferentes níveis de comprometimento organizacional. A aplicação da Análise em Componentes Principais Categórica (CatPCA) permitiu reduzir a dimensionalidade dos dados e sintetizar de uma forma visual os principais resultados do estudo.
- Economic and financial model to the mass‐rearing of Macrolophus pygmaeus (Rambur) (Heteroptera: Miridae), a biological control agent against the tomato moth Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in protected culturePublication . Dutra, Tiago M.; Batista, Maria Da Graça; Teixeira, João; Todorova, Silvia; Oliveira, Luísa; Tavares, João; Borges, Isabel; Soares, António O.ABSTRACT: BACKGROUND - Tuta absoluta (Meyrick) is a major pest of tomato produced in glasshouses and open field, causing severe damages to crops, reducing the quality of tomato fruits. The current maintenance of the pest populations below the economic threshold is not achieved by natural and classical control, thus requiring the continuous application of biological control agents (BCAs), under an augmentative or inoculative approach. The present study aims to develop an economic and financial model to evaluate the commercial viability of a continuous mass production of Macrolophus pygmaeus (Rambur), a BCA commonly used against the tomato moth, Tuta absoluta, in protected culture. The estimations for our model were based on two approaches: the farm-level impact analysis and the benefit–cost analysis. RESULTS - The results of the farm-level analysis show that the adoption of a more sustainable biological control approach is profitable for farmers and the benefit–cost analysis provides evidence that the investment on a new factory dedicated to the mass rearing of M. pygmaeus to control tomato moth populations generates a positive net present value (NPV) of 7.2 million euros, corresponding to an internal rate of return (IRR) of 28.4% per year. CONCLUSION - Our results are in line with (i) the more recent European Commission proposals for a new Regulation on sustainable use of plant protection products, which includes the reduction of 50% the use and risk of chemical pesticides by 2030 and (ii) most of the existing literature which conclude that new projects on BCA production are worth investments.