Browsing by Issue Date, starting with "2015-12"
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- Transition to the maternal role in women with addiction problems to psychoactive substances: conceptual mapPublication . Henriques, Carolina; Botelho, Maria Antonia Rebelo; Catarino, HelenaThe transition to motherhood is seen as a phenomenon where are interwoven multiple variables, where the experience of being a mother can be so significant andfull of pleasure, as associated with suffering and unhappiness processes.If we associate this phenomenon, itself multidimensional, the problem of adding the psychoactive substances, the spectrum of its complexity increases, whereas the mother experiences a set of changes associated with pregnancy, childbirth and postpartum, at the same time with their behaviourto addition to psychoactive substances. Looking for the integration of the concepts involved in the problems of transition to the maternal role in women with addition problems to psychoactive substances, we used the conceptual map as a basic tool for the organization of scientific knowledge in the field of study. We conclude from its analysis, that women with addition problems to psychoactive substances, in the process of transition to the maternal role, experience adjustment processes of adaptation and transition, where their past contexts, present and future perspectives converge maternal identity, as the individual characteristics of each woman (self-esteem, personal integrity and self-confidence).
- Fatigue behaviour of epoxy-steel single lap joints under variable frequencyPublication . Reis, P.N.B.; Monteiro, J.F.R.; Pereira, António; Ferreira, J.F.R.; J.D.M. CostaThis work investigates the loading frequency effects on the fatigue behaviour of adhesively-bonded steel lap joints. S-N diagrams of fatigue tests, under constant amplitude loading, were obtained for frequencies ranging between 2 and 40 Hz. The fatigue life for variable frequency tests was estimated based on constant frequency S-N curves, using a linear cumulative damage rule. It is possible to conclude that, for the higher shear stresses, the frequency presents only a marginal effect on fatigue life. On the other hand, for the lower shear stresses, the fatigue life of the adhesive joints is very dependant on the frequency level. Good correlations were obtained between fatigue life predictions and experimental results. © 2015 Elsevier Ltd. All rights reserved.
- Geometric transforms and reference picture list optimization for efficient disparity compensationPublication . Ricardo J. S. Monteiro; M. M. Rodrigues, Nuno; Faria, SergioThis paper presents a method to increase the efficiency of the disparity compensation process performed by state-of-the-art video coding extensions for 3D and multiview. Disparity compensation relies traditionally on a block matching algorithm limited to two degrees of freedom, that in many cases does not adequately address the disparity created by the camera arrays. The proposed method is combined with MV-HEVC in order to improve the efficiency of inter-frame prediction, by generating additional reference pictures, using 3D scene information. The new geometrically compensated pictures are chosen and reordered based on their usefulness for prediction and associated cost in the encoding process. When compared to MV-HEVC, the proposed scheme is able to achieve bitrate savings of up to 3.19% for convergent camera arrangements and 2.41% for parallel camera arrangements.
- Contributions to lossless coding of medical images using minimum rate predictorsPublication . Joao M. Santos; Guarda, André; M. M. Rodrigues, Nuno; Faria, SergioMedical imaging compression is experiencing a growth in terms of usage and image resolution, namely in diagnostics systems that require a large set of images, like MRI or CT. Furthermore, legal and diagnosis restrictions impose the use of lossless compression and data archival for several years. These facts create a demand for more efficient compression tools, used for archiving and communication. In this work, we first evaluate the performance of traditional medical image compression algorithms against that of recent state of the art lossless image encoders. We then propose a method to improve the Minimum Rate Predictors lossless encoder, by exploiting inter picture redundancy in volumetric anatomical images. Results show that the proposed method is more efficient than state of the art encoders, such as HEVC, by about 28.8%, and achieves a gain of up to 57.8% in compression ratio when compared with traditional methods.
- Effect of adherends and environment on static and transverse impact response of adhesive lap jointsPublication . Reis, P.N.B.; Soares, J.R.L.; Pereira, António; Ferreira, J.A.M.Impact response of adhesive joints has received limited attention compared to quasi-static loading. On the other hand, there are very few studies combining moisture and its effect on the impact strength. Therefore, the present paper aims to study the effect of moisture on the tensile and impact strength of single lap joints with different adherends (high limit elastic steel and a commercial composite). It was possible to conclude that adhesive joints with steel adherends are very sensitive to the environment and exposure time. For adhesive joints with composite adherends, the water showed a marginal effect. A marked hygrothermal effect was observed for all joints. For impact loads the environment effect is similar, but much more severe than that observed in tensile tests. For both tests, adhesive failures occurred for adhesive joints with steel adherends and delaminations for joints involving composite.
- On the mechanical properties of PLC–bioactive glass scaffolds fabricated via BioExtrusionPublication . Fiedler, T.; Videira, A.C.; Bartolo, Paulo; Strauch, M.; Murch, G.E.; Ferreira, J.M.F.This paper addresses the mechanical characterization of polycaprolactone (PCL)–bioglass (FastOs®BG) composites and scaffolds intended for use in tissue engineering. Tissue engineering scaffolds support the self-healing mechanism of the human body and promote the regrowth of damaged tissue. These implants can dissolve after successful tissue regeneration minimising the immune reaction and the need for revision surgery. However, their mechanical properties should match surrounding tissue in order to avoid strain concentration and possible separation at the interface. Therefore, an extensive experimental testing programme of this advanced material using uni-axial compressive testing was conducted. Tests were performed at low strain rates corresponding to quasi-static loading conditions. The initial elastic gradient, plateau stress and densification strain were obtained. Tested specimens varied according to their average density and material composition. In total, four groups of solid and robocast porous PCL samples containing 0, 20, 30, and 35% bioglass, respectively were tested. The addition of bioglass was found to slightly decrease the initial elastic gradient and the plateau stress of the biomaterial scaffolds.
- Searching for the corner seismic moment in worldwide dataPublication . Felgueiras, Miguel; Santos, Rui; Oliveira Martins, João PauloIn this paper the existence of the corner frequency value for the seismic moment distribution is investigated, analysing worldwide data. Pareto based distributions, usually considered as the most suitable to this type of data, are fitted to the most recent data, available in a global earthquake catalog. Despite the undeniable finite nature of the seismic moment data, we conclude that no corner frequency can be established considering the available data set. © 2015 AIP Publishing LLC.
- Distributed processing system for gas odorizationPublication . Reis, Mario; Perdigoto, Filipe; Pires, Antonio; Henriques, Fernando; Faria, Sergio; Fernandes, Telmo, Telmo Rui Carvalhinho Cunha, Telmo R.This paper proposes an advanced industrial controller prepared for hazardous industrial environments, namely natural gas odorisation. Its design and conception is focused on robustness and reliability, with high flexibility to allow local and remote monitoring and control. Instead of a centralized approach, where the computational load relies on a unique processor, we propose a distributed architecture, where the various control tasks are distributed among the existing microprocessors, like in a DCS system, but yet exhibiting a fast response time between inputs and outputs, like a PLC.The proposed architecture presents a high degree of flexibility and scalability, in order to allow an easy addition of new modules. By resorting to a script language interpreter installed in each I/O board, they may be reconfigured to a different functionally, thus increasing the system reliability and safety. An efficient and synchronized communication between boards ensures that all memory boards share the system status information, thus allowing each board to process individually. With the same performance and flexibility of a high-end PLC controller with full extras, like tactile HMI and TCP/IP remote control, we present an affordable gas odorizing system, which can be easily adapted for other industrial applications.
- Physical therapy provision in multiple sclerosis across Europe: a regional lottery?Publication . Rasova, K; Martinkova, P; Pavlikoma, M; Cattaneo, D; Jonsdottir, J; Henze, T; Baert, I; Van Asch, P; Santovo, C; Smedal, T; Beiske, A G; Stachowiak, M; Kovalewski, M; Nedeljkovic, U; Bakalidou, D; Alves-Guerreiro, José; Nilsagård, Y; Dimitrova, E N; Habek, M; Armutlu, K; Donzé, C; Ross, E; Ilie, A M; Martić, AThis paper provides information about an ongoing multi-staged online web questionnaire survey established by a core group within the Special Interest Group in Mobility, Rehabilitation in Multiple Sclerosis (www.eurims.org). The aims of the survey were to document the following across Europe: the availability and setting in which physical therapy for multiple sclerosis (MS) is delivered; the level of awareness and knowledge of different physical therapy approaches; the actual content of physical therapy and applied evaluation tools.
- Transcranial direct current stimulation in the neuromodulation of pain in fibromyalgia: A case study.Publication . DalĺAgnol, L; Pascoal-Faria, Paula; Barros Cecílio, S; Corrêa, F IAssessing effects of herbivory across broad gradients of varying ocean climate conditions and over small spatial scales is crucial for understanding its influence on primary producers. Effects of herbivory on the distribution and abundance of kelp recruits were examined experimentally at two regions under contrasting ocean climate. Specifically, the abundance and survivorship of kelp recruits and the abundance of macro-herbivores were compared between a ‘cool’ and a ‘warm’ region in northern and central Portugal, respectively. In each region, the abundance of kelp recruits and the intensity of grazing were compared between habitats of different topography within reefs (open reef vs. crevices). Compared to the ‘warm’ region, the abundance of kelp recruits was 3.9 times greater in the ‘cool’ region, where 85% of recruits were found in open reef habitats. In contrast, 87% of recruits in the ‘warm’ region were restricted to crevices. The ‘warm’ region had 140 times greater abundances of sea urchins, 45 times more herbi vorous fish and 4.1 times more grazing marks on kelp recruits than the ‘cool’ region. Grazing assays showed ca. 50 times higher rates of kelp biomass consumption, mainly by fishes, and zero survivorship of kelp recruits in the ‘warm’ relative to the ‘cool’ region. This study suggests both temperature and herbivores affect abundances of kelp recruits across latitudes, and demonstrates how herbivores affect their distribution at local scales, driving kelp recruits into ‘hiding’ in crevices under intense herbivory. Consequently, where net recruitment success is compromised by herbivory, the persistence of kelps will be contingent on availability of topographical refuges.