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Service Orientation has been an extensively used approach to model the services Collaborative Networks' (CN) members are willing to provide to customers. The evolution of this paradigm has followed an improvement path since its early forms. Nevertheless bottlenecks still exist, namely in what concerns: 1) a gap between the business and the information and communication technology perspectives; 2) an adequate Quality of Service (QoS) assessment mechanism for the CN context. As a contribution to these issues, this paper proposes: 1) the creation of a collaborative Service Ecosystem, introducing pro-activeness elements towards an auto-initiative representation of CN member's services; 2) the introduction of a QoS mechanism needed to facilitate the assessment of services in a CN context.

Within a Collaborative Business Ecosystem context, as the network evolves, the competition between members increases and, as a consequence, members face the challenge to improve the chances their services have to be selected. On the other hand, the distance between Business Services and “Computational Services” is still a bottleneck for the automation of service provision. This paper extends the Pro-Active Service Entity Framework, proposing a mechanism to improve the service selection chances, based on the refinement of a Quality of Service concept for this context, and introduces a new class of actors for the framework – the intermediaries, needed to shorten the distance between Business and Computational perspectives.

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Supply chains ({SC)} in an attempt to be more competitive, are adopting new management paradigm. Among these paradigms there are four that deserve particular mention because of their importance to better {SC} performance: lean, agile, resilient and green. The main objective of this paper is to propose a conceptual model for a lean, agile, resilience and green {SC}, with the purpose of improving their operational, economic and environmental performance. In this attempt a set of {SC} management practices, which were named {LARG} practices, and several performance measures are suggested. This model is based in the literature review about the four {SC} management paradigms and also {SC} performance measurement. Among the suggested {LARG} practices the ones influencing more the {SC} performance are the just in time and also the supplier relationships. Also the {SC} performance measures with more {LARG} practices influencing them are the inventory levels and the time, that is, the {SC's} operational performance is the most affected.

The objective of this study was to analyse the behaviour of prestress strand anchorages by bonding with an epoxy adhesive for structural strengthening use. Pull-out and push-in tests were carried out on 15·2 mm diameter prestress steel strands sealed in 18 mm diameter holes with several embedment lengths, complemented by long-term tests. Experimental results are presented and compared with theoretical results regarding maximum pull-out and transmittable loads and also draw-in results. Theoretical results are obtained by solving the governing equation of the bond phenomenon adopting a non-linear local bond/slip law derived from pull-out tests with short embedment length. The study shows that it is reasonable to assume an average constant bond stress for anchorage design with the studied epoxy adhesive in the range of the studied values of anchor embedment length and diameter. The average values for bond stress to be used for determining the maximum pull-out and transmittable loads were found to be 12·0 and 5·2 MPa, respectively. Experimental draw-in values show a great variability, and so determining transmission length based on draw-in values may lead to a false perception that the transmission length is very variable.

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A three-dimensional (3D) numerical implementation of the limit analysis upper-bound theorem is used to determine passive horizontal earth-pressure coefficients. An extension technique allowing determination of the 3D passive earth pressures for any width-to-height ratios greater than 7 is presented. The horizontal passive earth-pressure coefficients are presented and compared with solutions published previously. Results of the ratio between the 3D and two-dimensional horizontal passive earth-pressure coefficients are shown and found to be almost independent of the soil-to-wall friction ratio. A simple equation is proposed for calculating this passive earth-pressure ratio.

Photosynthesis is one of the key processes to be affected by water deficits, via decreased CO2 diffusion to the chloroplast and metabolic constraints. The relative impact of those limitations varies with the intensity of the stress, the occurrence (or not) of superimposed stresses, and the species we are dealing with. Total plant carbon uptake is further reduced due to the concomitant or even earlier inhibition of growth. Leaf carbohydrate status, altered directly by water deficits or indirectly (via decreased growth), acts as a metabolic signal although its role is not totally clear. Other relevant signals acting under water deficits comprise: abscisic acid (ABA), with an impact on stomatal aperture and the regulation at the transcription level of a large number of genes related to plant stress response; other hormones that act either concurrently (brassinosteroids, jasmonates, and salycilic acid) or antagonistically (auxin, cytokinin, or ethylene) with ABA; and redox control of the energy balance of photosynthetic cells deprived of CO2 by stomatal closure. In an attempt to systematize current knowledge on the complex network of interactions and regulation of photosynthesis in plants subjected to water deficits, a meta-analysis has been performed covering > 450 papers published in the last 15 years. This analysis shows the interplay of sugars, reactive oxygen species (ROS), and hormones with photosynthetic responses to drought, involving many metabolic events. However, more significantly it highlights (i) how fragmented and often non-comparable the results are and (ii) how hard it is to relate molecular events to plant physiological status, namely photosynthetic activity, and to stress intensity. Indeed, the same data set usually does not integrate these different levels of analysis. Considering these limitations, it was hard to find a general trend, particularly concerning molecular responses to drought, with the exception of the genes ABI1 and ABI3. These genes, irrespective of the stress type (acute versus chronic) and intensity, show a similar response to water shortage in the two plant systems analysed (Arabidopsis and barley). Both are associated with ABA-mediated metabolic responses to stress and the regulation of stomatal aperture. Under drought, ABI1 transcription is up-regulated while ABI3 is usually down-regulated. Recently ABI3 has been hypothesized to be essential for successful drought recovery.