5 resultados para N5 - Agriculture, Natural Resources, Environment, and Extractive Industries
em Instituto Politécnico do Porto, Portugal
Resumo:
This work reports a relatively rapid procedure for the forecasting of the remediation time (RT) of sandy soils contaminated with cyclohexane using vapour extraction. The RT estimated through the mathematical fitting of experimental results was compared with that of real soils. The main objectives were: (i) to predict the RT of soils with natural organic matter (NOM) and water contents different from those used in experiments; and (ii) to analyse the time and efficiency of remediation, and the distribution of contaminants into the soil matrix after the remediation process, according to the soil contents of: (ii1) NOM; and (ii2) water. For sandy soils with negligible clay contents, artificially contaminated with cyclohexane before vapour extraction, it was concluded that: (i) if the NOM and water contents belonged to the range of the prepared soils, the RT of real soils could be predicted with relative differences not higher than 12%; (ii1) the increase of NOM content from 0% to 7.5% increased the RT (1.8–13 h) and decreased the remediation efficiency (RE) (99–90%) and (ii2) the increase of soil water content from 0% to 6% increased the RT (1.8–4.9 h) and decreased the RE (99–97%). NOM increases the monolayer capacity leading to a higher sorption into the solid phase. Increasing of soil water content reduces the mass transfer coefficient between phases. Concluding, NOM and water contents influence negatively the remediation process, turning it less efficient and more time consuming, and consequently more expensive.
Resumo:
This study examined the joint effects of home environment and center-based child care quality on children’s language, communication, and early literacy development, while also considering prior developmental level. Participants were 95 children (46 boys), assessed as toddlers (mean age = 26.33 months;Time 1) and preschoolers (mean age = 68.71 months; Time 2) and their families. At both times, children attended center-based child care classrooms in the metropolitan area of Porto, Portugal. Results from hierarchical linear models indicated that home environment and preschool quality, but not center-based toddler child care quality, were associated with children’s language and literacy outcomes at Time 2. Moreover, the quality of preschool classrooms moderated the association between home environment quality and children’s language and early literacy skills – but not communication skills – at Time 2, suggesting the positive cumulative effects of home environment and preschool quality. Findings further support the existence of a detrimental effect of low preschool quality on children’s language and early literacy outcomes: positive associations among home environment quality and children’s developmental outcomes were found to reduce substantially when children attended low-quality preschool classrooms.
Resumo:
This paper examines the relationship between the level of satisfaction towards Human Resources Management practices among repatriates and the decision to remain on the home company after expatriation. Data was collected through semi-structured interviews of 28 Portuguese repatriates who remain and 16 organisational representatives from eight companies located in Portugal. The results show that (1) compensation system during the international assignment; (2) permanent support during the international assignment and; (3) recognition upon the return of the work and effort of expatriates during the international assignment are the most important HRM practices for promoting satisfaction among repatriates. Moreover, it is at repatriation phase that repatriates show higher dissatisfaction with HRM support. These findings will be discussed in detail and implications and suggestions for future research will be proposed as well.
Resumo:
The purpose of this study is to investigate the association between the satisfaction with HRM practices in an organization and the workers' perceived performance. We are interested in learning if indeed workers that are more satisfied with the organization’s practices will also perceive themselves as more hardworking than others, thus confirming the happy-productive worker hypothesis, from an individual perception standpoint. Data originates from a large Portuguese hospital, with a sample of 952 clinical and nonclinical hospital workers. Data was originally explored using SPSS software and later tested in AMOS software where a multiple regression model was constructed and tested. Results indicate that overall satisfaction with HRM practices are related with the workers’ perceived performance; most of the HRM satisfaction subscales also relate, except for pay and performance appraisal, that do not seem to be good predictors of the workers perceived performance. The present study is based on a single large public hospital, and thus, these findings need to be further tested in other settings. This study offers some clues regarding the areas of HRM that seem to be more related with the workers’ perceived performance, and hence provide an interesting framework for managers dealing with healthcare teams. This study contributes to the happy-productive worker hypothesis research, by including seldom used variables in the equation and taking a different perspective. Results provide new clues for investigation and practice regarding the areas of action in HRM that seem to be more prone to elicit perceived effort from the workers.