2 resultados para Hydrophobic and Hydrophilic Interactions
em Repositório Digital da UNIVERSIDADE DA MADEIRA - Portugal
Resumo:
Tomato (Lycopersicon esculentum L.) is one of the main constituents of the Mediterranean diet. Its consumption has been proposed to reduce the risk of cardiovascular diseases and certain types of cancer. It is therefore one of the most popular and extensively consumed vegetable crop worldwide. To gain insights on the potential of Lycopersicon esculentum L. as bioactive food, two analytical methodologies were developed to determine the levels of the lipophilic -tocopherol, α-tocopherol, β-carotene, lycopene; and hydrophilic antioxidants ascorbic acid. The quantification of total carotenoids (β-carotene and lycopene) was assessed through a liquid–liquid ultrasound assisted extraction (LL-USAE) in combination with ultraviolet-visible spectroscopy (UV-Vis), according to method of mean, for total carotenoids (λmáx = 450 nm. The ultra-high performance liquid chromatographic using both photodiode array and fluorescence detection (UHPLC-PDA/FLR), allows the identification and quantification of the target lipophilic and hydrophilic antioxidants. This methodology UHPLC-PDA/FLR is fast, simple and revealed a high sensitivity for the compounds under study. The limits of detection (LODs) and quantification (LOQs) obtained were much lower (about 10 times) than the reported in literature. The method LL-USAE/UV-Vis was validated and applied to different tomato foodstuffs. The results reveal a small increase of carotenoids content during maturation, reaching the maximum level when ripe. These results complement those obtained by the ORAC and TBARS assays that show an increase of antioxidant capacity during maturation. The LODs ans LOQs obtained were also about 10 times lower than reported in literature. The carotenoid content was also evaluated by LL-USAE/UV-Vis in different tomatoes varieties. Regional variety present the high carotenoid level, followed by campari and gordal, and at last grape. This methodology was also applied to different processed food samples containing tomatoes derivatives. Highest carotenoids content were obtained in concentrated tomato foodstuffs.
Resumo:
In many creative and technical areas, professionals make use of paper sketches for developing and expressing concepts and models. Paper offers an almost constraint free environment where they have as much freedom to express themselves as they need. However, paper does have some disadvantages, such as size and not being able to manipulate the content (other than remove it or scratch it), which can be overcome by creating systems that can offer the same freedom people have from paper but none of the disadvantages and limitations. Only in recent years has the technology become massively available that allows doing precisely that, with the development in touch‐sensitive screens that also have the ability to interact with a stylus. In this project a prototype was created with the objective of finding a set of the most useful and usable interactions, which are composed of combinations of multi‐touch and pen. The project selected Computer Aided Software Engineering (CASE) tools as its application domain, because it addresses a solid and well‐defined discipline with still sufficient room for new developments. This was the result from the area research conducted to find an application domain, which involved analyzing sketching tools from several possible areas and domains. User studies were conducted using Model Driven Inquiry (MDI) to have a better understanding of the human sketch creation activities and concepts devised. Then the prototype was implemented, through which it was possible to execute user evaluations of the interaction concepts created. Results validated most interactions, in the face of limited testing only being possible at the time. Users had more problems using the pen, however handwriting and ink recognition were very effective, and users quickly learned the manipulations and gestures from the Natural User Interface (NUI).