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A crescente importância política, económica e social dos países em vias de desenvolvimento, a evolução rápida da sua população fez concentrar, durante o século XX, as atenções da opinião pública quase exclusivamente no crescimento demográfico. Quando se falava em população, falava-se sempre no receio das consequências da explosão demográfica. Os cenários elaborados pelas Nações Unidas, na segunda metade do século XX, apontavam para um mundo, no final do século XXI, com uma população próxima dos 20 milhares de milhão de habitantes (quatro vezes mais a população mundial existente em 1990 - 5 milhares de milhão).

A multidisciplinary, long term project aimed at developing and testing assessment and evaluation tools for the ecological management of the landscape is being developed in the University of Évora (Portugal). The main project is divided in three sub-projects (Characterization of the conservation value of the SE Alentejo Region; Identification of the main ecological processes and functions in Évora; and Analysis of the significance of ecological characterization methods in Apostiça). The main objectives to be achieved are to describe the ecological potential of the landscape, and determine the land-use practices and land-use intensities necessary to ensure the maintenance and promotion of the conservation value of landscape, in order to assess the ecological value of a land-use structure and also evaluate the sustainability of alternative land-use patterns. As preliminary conclusions we could say that the evaluation of the stability of a landscape by comparing the degree of correspondence of the nature of both levels of characterization - land-use distribution and homogeneous landscape units - is of particular importance in the evaluation of the fragmentation degree of that landscape, and the real disturbance determined by proposed land-use changes.

No presente artigo é apresentado o trabalho realizado no Laboratório de Sistemas Industriais, onde se pretende controlar a passagem de objectos num tapete rolante através de visão por computador. O sistema desenvolvido consiste num tapete rolante accionado por um servo motor da OMRON, com transmissão por correia. O controlo do servo motor é realizado por computador através de uma placa da National Instruments PCI-7344 com o adaptador UMI-7764. O sistema de visão consiste numa placa Matrox Meteor II e uma câmara CCD a cores. Pretende-se controlar a velocidade do tapete em função do numero de objectos a identificar e do tempo de processamento do anel de visão. Para tal foi necessário calibrar o sistema de visão, baseado num PC- Pentium II a 350 MHz com 32 Mb de RAM, tendo o software sido desenvolvido em Visual C++. O sistema de controlo encontra-se centralizado num PC-Pentium III a 850 MHz com 128 Mb de RAM, tendo o software sido desenvolvido no programa LABVIEW

The aim of this work is to evaluate the methodology to obtain an extract rich in caffeic acid (CAD) derivatives in spent coffee ground (SCG) and evaluate its free radical scavenging activity. Eighteen SCG samples and coffee beverage were collected from different brands and coffee shops. The SCG extracts were prepared by three methods: A) ethanol 96o according Campos et al [1]; B) extracts prepared in A were hydrolysed with HCl 37% (1:10), according Markham [2]; C) water extraction. All samples were screened by HPLC/DAD for phenolic profile characterization and structural identification and quantification of CAD [1]. Among caffeine the majority of the compounds found in the coffee beverage were CAD and in the SCG the compounds remaining the same. The hydrolysed extracts confirmed its existence, possible as glycosides (Fig. 1). The matrix resulting from the hydrolysis of the SCG can also be used to explore further bioactivities for therapeutic consideration once the released aglycones are in general more active. Method A was the most efficient (4.305 mg CAD/g SCG). Nevertheless the results were different according to the products. The caffeine ratio between SCG and expresso coffee was 17% and the ratio of CAD in both samples was 8%. A significant free radical scavenging potential (activity of DPPH) was founded yet in SCG (EC50 = 1.857 µg/mL) comparing with the coffee beverage (EC50 = 0.172 µg/mL) around 10% lower. The results show that the SCG has potential for future biological screening showing a stable compound profile and constitutes a much simpler matrix than the beverage, simplifying its analysis and further studies for potential bioactivities.