Browsing by Author "Ferreira, Isabel"
Now showing 1 - 5 of 5
Results Per Page
Sort Options
- Environmental impact of intensive horticulture practices on groundwater content of nitrates, sodium, potassium and pesticidesPublication . Pinto, Edgar; Melo, A.; Mansilha, C.; Ferreira, IsabelRecent changes in agricultural practices during the last 20th century have significantly contributed to increase the concentrations of pollutant substances is water, soil and air. Groundwater is a valuable natural resource and as such should be protected from deterioration and chemical pollution. A monitoring program of nitrate, nitrite, potassium, sodium and 28 pesticides was carried out in water samples from an intensive horticulture area in a vulnerable zone from North of Portugal. Eight collecting points were selected and water analyzed in five sampling campaigns, during one year.
- Exposure risks to carcinogens in food: formation of heterocyclic aromatic amines (HAs) and polycyclic aromatic hydrocarbons (PAHs) in grilled muscle foodsPublication . Pinto, Edgar; Viegas, O.; Pinho, O.; Ferreira, IsabelDiet contains almost all the necessary ingredients to support the human life. However, chemicals that had a deleterious effect may also be present. Such chemicals can occur naturally in the food, others are synthetic and some are produced during cooking. Cooking toxicants have been receiving special attention in the last decades concerning their formation, occurrence, mitigation, and the impact on human health. The risk of exposure to these compounds depends on the kind of diet, eating habits and cooking practices.
- Influence of Soil Chemistry and Plant Physiology in the Phytoremediation of Cu, Mn, and ZnPublication . Pinto, Edgar; Aguiar, Ana; Ferreira, IsabelDifferent anthropogenic sources of metals can result from agricultural, industrial, military, mining and urban activities that contribute to environmental pollution. Plants can be grown for phytoremediation to remove or stabilize contaminants in water and soil. Copper (Cu), manganese (Mn) and zinc (Zn) are trace essential metals for plants, although their role in homeostasis in plants must be strictly regulated to avoid toxicity. In this review, we summarize the processes involved in the bioavailability, uptake, transport and storage of Cu, Mn and Zn in plants. The efficiency of phytoremediation depends on several factors including metal bioavailability and plant uptake, translocation and tolerance mechanisms. Soil parameters, such as clay fraction, organic matter content, oxidation state, pH, redox potential, aeration, and the presence of specific organisms, play fundamental roles in the uptake of trace essential metals. Key processes in the metal homeostasis network in plants have been identified. Membrane transporters involved in the acquisition, transport and storage of trace essential metals are reviewed. Recent advances in understanding the biochemical and molecular mechanisms of Cu, Mn and Zn hyperaccumulation are described. The use of plant-bacteria associations, plant-fungi associations and genetic engineering has opened a new range of opportunities to improve the efficiency of phytoremediation. The main directions for future research are proposed from the investigation of published results.
- Initial dilemmas in IST research: design science and design research, a clarification of conceptsPublication . Ferreira, Isabel; Silva, Cândida; Ferreira, Sílvia; Carvalho, João ÁlvaroThe inter-disciplinarity of information systems, applied discipline and activity of design, and the study from different paradigms perspectives explains the diversity of problems addressed. The context is broad and includes important issues beyond technology, as the application, use, effectiveness, efficiency and their organizational and social impacts. In design science, the research interest is in contributing to the improvement of the processes of the design activity itself. The relevance of research in design science is associated with the result obtained for the improvement of living conditions in organizational, inter-organizational and Society contexts. In the research whose results are artifacts, the adoption of design research as a process of research is crucial to ensure discipline, rigor and transparency. Based on a literature review, this paper clarifies the terms of design science and design research. This is the main motivation for presenting this paper, determinant for the phase in research in technologies and information systems which are the three research projects presented. As a result the three projects are discussed in relation to the concepts of design science and design research.
- Interpretative research in information systems: two qualitative research design projectsPublication . Silva, Cândida; Ferreira, Isabel; Ramos, Isabel; Amaral, LuísIn a scientific research project is important to define the underlying philosophical orientation of the project, because this will influence the choices made in respect of scientific methods used, as well as the way they will be applied. It is crucial, therefore, that the philosophy and research design strategy are consistent with each other. These questions become even more relevant in qualitative research. Historically, the interpretive research philosophy is more associated to the scientific areas of social sciences and humanities where the subjectivity inherent to human intervention is more explicitly defined. Information systems field are, primarily, trapped in computer science field, though it also integrates issues related with management and organizations field. This shift from a purely technological guidance for the consideration of the problems of management and organizations has fostered the rise of research projects according to the interpretive philosophy and using qualitative methods. This paper explores the importance of alignment between the epistemological orientation and research design strategy, in qualitative research projects. As a result, it is presented two PhD projects, with different research design strategies, that are being developed in the technology and information systems field, in the light of the interpretive paradigm.