The role of competencies and interests in developing complex IT-artefacts: the case of a metering system.

In this paper we aim at contributing to the ongoing debate on the relationship between artefacts and organizational structuration. Current literature emphasises the role of artefacts as mediators between interests of different categories of actors, namely between designers and users. Alternatively, it concentrates on the processes of learning and interacting between each actor and the artefacts themselves. We explore an arrangement which is not captured by these characterizations, and yet is becoming more and more common, that is situations in which complexity imposes an integration of different actors focusing on knowledge domains which are only partly overlapping. To explore these issues, we examine the dynamics surrounding the design of a complex artefact: an electronic metering system developed by a consortium of firms. The main results emerging from the case study are 1) the relevance of each actor's interests as the main rationale for explaining the technical features of the artefact; 2) the role of negotiation and consensus in determining the final shape of the artefact in term of its features; 3) the bundling/unbundling of features within the physical object as the cooperative effort rises/falls.artefacts; interests; ambiguity; competencies

Sustainable cooperative distance learning system for education in developing countries

The use of Information and Communication Technologies (ICTs) in a cooperative way can give a good improvement in the educational field; in developing countries, especially in Sub-Saharan area. Sustainable technologies and collaborative LMS are investigated in a case study as possible ways to improve, towards distance learning systems, education and towards it, social empowerment and development. A web-based system, customized for an academic year proposal in medicine and surgery field, helps the development of cooperation among universities and research empowerment and exchange, useful for both entities and their stakeholders. Different uses and approaches to the technological solution allow different participants to model and interact with the project despite difficulties and environmental gabs that could occur in some territories of the Sub-Saharan countries

Studies on the Synthesis of Vitamin D Analogs with Aromatic D-Ring

Herein, we describe our studies on the synthesis of 1α,25-dihydroxyvitamin D3 analogs possessing a benzene ring replacing the natural 5-membered D-ring by the Wittig-Horner and dienyne approaches. A key feature is the synthesis of a Cr(CO)3-complexed previtamin D derivative that enables the construction of vitamin D analogs with aromatic D-ring through a thermal [1,7]-H sigmatropic shift. This study establishes the basis for the design of new vitamin D analogs containing aromatic D-ring, complexed or uncomplexed to Cr(CO)3 type moieties for specific molecular recognition and drug research and developmentWe thank Xunta de Galicia (project GPC2014/001) and for financial support. Silvina Eduardo thanks the Spanish MEC for a fellowship. Rita Sigüeiro thanks Xunta de Galicia for a post-doctoral fellowship (Axudas posdoutorais, plan I2C, mod B)S

Determination of density and concentration from fluorescent images of a gas flow

A fluorescent image analysis procedure to determine the distribution of species concentration and density in a gas flow is proposed. The fluorescent emission is due to the excitation of atoms/molecules of a gas that is intercepted by an electron blade. The intensity of the fluorescent light is proportional to the local number density of the gas. When the gas flow is a mixture of different species, this proportionality can be exploited to extract the contribution associated to the species from the spectral superposition acquired by a digital camera. This yields a method that simultaneously reveals species concentrations and mass density of the mixture. The procedure is applied to two under-expanded sonic jets discharged into a different gas ambient - Helium into Argon and Argon into Helium - to measure the concentration and density distribution along the jet axis and across it. A comparison with experimental and numerical results obtained by other authors when observing under-expanded jets at different Mach numbers is made with the density distribution along the axis of the jet. This density distribution appears to be self-similar.Comment: New figures in portable .eps forma

Hypersonic Jets in Astrophysical Conditions: Focus on Spreading and Asymmetric Stability Properties

High Mach number jets emanating from young stars show remarkable collimation, low opening angle and resilience against the growth of instabilities, especially the asymmetric ones. In recent laboratory experiments instances of asymmetric three-dimensional low amplitude long waves aligned with the jet axis were observed by Belan et al (2013 Astron. Astrophys. 554 A99). To explore the collimation, spreading, and asymmetric stability properties of hypersonic jets we carried out laboratory experiments and numerical simulations in two and three spatial dimensions. We find that laboratory hydrodynamic jets with high Mach numbers remain collimated, for hundreds of jet radii in length and maintain low opening angles. These findings are confirmed by 3D numerical simulations carried out after time-dependent, asymmetric perturbations are applied at the jet inlet. Both experimental and perturbed simulated jets show non-axial modes with long wavelengths, whose growth does not disrupt the jet in the domain considered

image segmentation and polishing of the surface

Publisher Copyright: © SISEF.The identification of Amazonian timber species is a complex problem due to their great diversity and the lack of leaf material in the post-harvest inspec-tion often hampers a correct recognition of the wood species. In this context, we developed a pattern recognition system of wood images to identify com-monly traded species, with the aim of increasing the accuracy and efficiency of current identification methods. We used ten different species with three polishing treatments and twenty images for each wood species. As for the image recognition system, the textural segmentation associated with Haralick characteristics and classified by Artificial Neural Networks was used. We veri-fied that the improvement of sandpaper granulometry increased the accuracy of species recognition. The developed model based on linear regression achieved a recognition rate of 94% in the training phase, and a post-training recognition rate of 65% for wood treated with 120-grit sandpaper mesh. We concluded that the wood pattern recognition model presented has the potential to correctly identify the wood species studied.publishersversionpublishe

Custom-Made Implants in Ankle Bone Loss: A Retrospective Assessment of Reconstruction/Arthrodesis in Sequelae of Septic Non-Union of the Tibial Pilon

Background and Objectives: Treating segmental tibial and ankle bone loss after radical surgery for chronic osteomyelitis is one of the most challenging problems encountered by orthopaedic surgeons. Open tibia and ankle fractures occur with an incidence of 3.4 per 100,000 and 1.6 per 100,000, respectively, and there is a high propensity of developing fracture-related infection with associated chronic osteomyelitis in patients. Segmental tibial and ankle bone loss have recently received new and improved treatments. Materials and Methods: Above all, 3D printing allows for the customization of implants based on the anatomy of each patient, using a personalized process through the layer-by-layer deposition of materials. Results: This article presents different cases from the authors' experience. Specifically, four patients suffered tibia and ankle fractures and after radical surgery for chronic osteomyelitis combined with high-performance antibiotic therapy underwent ankle reconstruction/arthrodesis with custom-made tibial spacers. Conclusions: Thanks to 3D-printed patient-specific devices, it is possible to perform surgical procedures that, for anatomical reasons, would have been impossible otherwise. Moreover, an improvement in overall functionality and an important reduction in pain were shown in the last follow-up in all patients

Identifying pathways between psychiatric symptoms and psychosocial functioning in the general population

The present study aims to identify pathways between psychiatric network symptoms and psychosocial functioning and their associated variables among functioning clusters in the general population. A cross-sectional web-based survey was administered in a total of 3,023 individuals in Brazil. The functioning clusters were derived by a previous study identifying three different groups based on the online Functioning Assessment Short Test. Networking analysis was fitted with all items of the Patient-Reported Outcomes Measurement Information System for depression and for anxiety (PROMIS) using the mixed graphical model. A decision tree model was used to identify the demographic and clinical characteristics of good and low functioning. A total of 926 (30.63%) subjects showed good functioning, 1,436 (47.50%) participants intermediate functioning, and 661 (21.86%) individuals low functioning. Anxiety and uneasy symptoms were the most important nodes for good and intermediate clusters but anxiety, feeling of failure, and depression were the most relevant symptoms for low functioning. The decision tree model was applied to identify variables capable to discriminate individuals with good and low functioning. The algorithm achieved balanced accuracy 0.75, sensitivity 0.87, specificity 0.63, positive predictive value 0.63 negative predictive value 0.87 (p<0.001), and an area under the curve of 0.83 (95%CI:0.79–0.86, p<0.01). Our results show that individuals who present psychological distress are more likely to experience poor functional status, suggesting that this subgroup should receive a more comprehensive psychiatric assessment and mental health care