612 research outputs found
Rice husk-earth based composites: A novel bio-based panel for buildings refurbishment
With the aim of developing economic and ecological bio-based composite panels to be used on indoor wall or ceiling coating systems, contributing to hygrothermal comfort and health, three different composite formulations were produced, differing on the content and pre-treatment of rice husk: 15% and 30%, only dried or previously boiled. Composite samples were tested for biological development and several physic-mechanical characteristics. Increasing on rice husk content decreases thermal conductivity due to bulk density decrease, decreasing ultrasound velocity, flexural strength, abrasion and fire resistance, but improving the moisture buffering capacity at least in 20%. For high rice husk-content composites, its pre-boiling decreases biological susceptibility although decreasing resistance to fire, most probably due to destruction of the cellulose wall, but significantly increases abrasion resistance and compressive strength, probably because of a better bond between the rice husk and the earthen matrix, quicker reaching a high water vapour adsorption limit
Interference suppression with physical-layer network coding and MIMO for multi-way channels
Orthogonal techniques (such as TDMA – time division multiple access) are traditionally used when a set of terminals wants to exchange data and a relay is required when wireless terminals cannot communicate directly. This paper proposes two schemes to address multi-way channels when a set of terminals wants to exchange data. Both proposed schemes consist of a first phase based on virtual MIMO with lattice reduction-aided (LRA) detection at the relay, establishing a multiple access channel (MAC). Two new strategies are then proposed for the second (multicast) phase; one for single antenna terminals and another for multiple-input multiple-output (MIMO) terminals. The second strategy achieves interference suppression by successively combining physical layer network coding and MIMO detection (with LRA detectors also at the terminals). The paper assesses a 3 terminals network with a relay for which a TDMA-based scheme would require 6 time-slots, while the proposed strategy for MIMO terminals is able to exchange the information between all terminals using 2 time-slots only. This latter scheme is easily scalable to a higher number of terminals, and always able to accomplish the exchange of messages between all of them in just 2 time-slots, although limited by the number of antennas that the terminals can fit and also the MIMO processing complexity they can afford.info:eu-repo/semantics/acceptedVersio
Qualidade nos cuidados de enfermagem: que realidade?
Este trabalho de revisão bibliográfica foi realizado no âmbito do IX Programa de Doutoramento em Enfermagem, do Instituto de Ciências da Saúde da Universidade Católica Portuguesa do Porto. A existência de sistemas de saúde que garantam a prestação efectiva de cuidados de qualidade é, actualmente uma das prioridades de variadas organizações, entre elas constam: a ODCE, OMS, SNS e OE. A qualidade dos cuidados de enfermagem para além da importância que tem para a instituição e doente, deve ter uma importância máxima para o prestador de cuidados. O enfermeiro deve almejar a qualidade em cada gesto realizado, deve procurar que o desempenho da sua função seja mais do que uma simples execução de tarefas (Ascensão, 2010). Objectivos: Conhecer o estado da arte em lÃngua portuguesa em termos da qualidade dos cuidados de enfermagem. Conhecer as metodologias usadas no estudo da qualidade dos cuidados de enfermagem. Material e Tratou-se de uma revisão de literatura tendo por finalidade identificar o conhecimento existente sobre esta temática. Foi realizada uma pesquisa na base de dados B-On, tendo em conta Dissertações de Licenciatura, de Mestrado, de Doutoramento e artigos, disponÃveis em texto integral, que tivessem como palavras-chave no tÃtulo: Cuidados, Qualidade e Enfermagem. A pesquisa foi efectuada para documentos em português entre os anos de 2000 e 2013. Resultados: A pesquisa encontrou, na B-on dezoito documentos, artigos de periódicos da área da saúde. Destes dezoito um artigo encontrava-se em quadruplicado e outro em duplicado. Quatro deles não foram incluÃdos por não dizerem respeito à área em questão. No final, após aplicação dos critérios de pesquisa, reunimos um conjunto de dez documentos (cinco teses, três artigos e duas comunicações em conferências) que se constituÃram como o nosso corpus de análise. Os documentos estão disponÃveis em texto integral. Discussão e Conclusão: Depois de analisados os documentos encontrados concluÃmos que os enfermeiros proporcionam um importante contributo na melhoria da qualidade das organizações (Aleixo, 2010). Conclui-se também que existe uma urgência na execução de ações de educação continuada, uma vez que a formação é considerada instrumento de reflexão e mudança, sendo esta um dos pilares para a prestação de cuidados de enfermagem de excelência (Padilha, 2010; Castro, 2007). Paralelamente, conclui-se que os principais resultados da qualidade dos cuidados de enfermagem envolvem mais trabalho e decisão em equipa multidisciplinar, mais recursos materiais e humanos e melhores condições fÃsicas (Carvalhais, 2010)
Aneuploidy facilitates dysplastic and tumorigenic phenotypes in the Drosophila gut
Aneuploidy has been strongly linked to cancer development, and published evidence has suggested that aneuploidy can have an oncogenic or a tumor suppressor role depending on the tissue context. Using the Drosophila midgut as a model, we have recently described that adult intestinal stem cells (ISCs), do not activate programmed cell death upon aneuploidy induction, leading to an increase in ISC proliferation rate, and tissue dysplasia. How aneuploidy impacts ISCs in intestinal tumorigenic models remains to be investigated, and it represents a very important biological question to address since data from multiple in vivo models suggests that the cellular impact of aneuploidy is highly dependent on the cellular and tissue context. Using manipulation of different genetic pathways such as EGFR, JAK-STAT and Notch that cause dysplastic phenotypes in the Drosophila gut, we found that concomitant aneuploidy induction by impairment of the Spindle Assembly Checkpoint (SAC) consistently leads to a more severe progression of intestinal dysplasia or tumorigenesis. This is characterized by an accumulation of progenitor cells, high tissue cell density and higher stem cell proliferation rates, revealing an additive or synergistic effect depending on the misregulated pathway in which aneuploidy was induced. Thus, our data suggests that in the Drosophila gut, both dysplasia and tumorigenic phenotypes can be fueled by inducing genomic instability of resident stem cells.This work was funded by National Funds through FCT – Fundação para a Ciência e a Tecnologia, I.P., under the project UIDB/04293/2020
A Novel Adaptive Lighting System Which Considers Behavioral Adaptation Aspects for Visually Impaired People
The number of visually impaired people and elderly people groups are significant, but the current lighting system used in buildings, which is based on the current standard, cannot provide the necessary lighting comfort for them. The lighting system should provide the correct illuminance for every activity and even pattern of light. This research presents the work in progress in developing the novel adaptive lighting system tailored for visually impaired people, which becomes the solution to the problem. The behavioral adaptation aspects and the experience and memory principle are taken into account in the system design. It also makes use of the latest independent adjustable artificial light (LED) technology, to get an even pattern of lighting, while still considering efficient energy usage. The proposed system structure uses a wireless sensor network (WSN), big data processing, and the Artificial Intelligence (AI) sub-system, which can predict and adaptively regulate the illumination level based on the occupant’s needs and routines. The initial simulation of the lighting model is presented in this paper. The simulation uses five scenarios in different seasons and daylight. The simulation shows satisfactory results for illuminance values 200, 250, 300, 500, and 750 lux, needed by the occupants
Assessing the impact of universities’ entrepreneurial activity on regional competitiveness
The aim of this study is to test the multidimensional construct of the Entrepreneurial University (EU), and therefore to confirm whether EU factors make a positive contribution to regional competitiveness. Data were collected from ten Portuguese Public Universities (PPUs) through a self-administered questionnaire. First- and second-order confirmatory factor analyses (CFA) were performed through factor and multiple linear regression analyses. The main findings show that EU related factors—perceived and combined with actual regional metrics—especially entrepreneurial supporting measures, positively contributed to regional competitiveness. This study shows policy makers that universities are not merely cost centres but provide knowledge spillovers that can have a positive influence on regional competitiveness.info:eu-repo/semantics/publishedVersio
Effectiveness of mortars composition on the embodied carbon long-term impact
Refurbishment activities represent more than 17% of the saving potential of the EU up to 2050. However, studies on buildings structure and finishing reparation of rendering mortars using LCA are still lacking. An innovative design approach is required to drive the minimisation of embodied carbon using objective performance information of buildings behaviour. This research work is focused on the reparation of rendering mortars and intends to demonstrate that the choice of mortars for buildings affects the maintenance actions needed and can increase the construction environment liability and embodied carbon expenditure. A new leaching risk analysis combined with LCA of different mortars composition (cement and lime based) was implemented enabling to predict the longevity of the rendering and the embodied carbon expenditure on 20th century buildings. It is demonstrated that some mortars may have a higher impact at the outset, such as cement-based mortars, but result in a much lower impact across the building service life. The embodied carbon of repair actions of mortars similar to OPC are expected to reduce the environmental impact of rendering repair actions at least in 10 times in comparison to less hydraulic mortars
Parallel strategies for Direct Multisearch
Publisher Copyright:
© 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Direct multisearch (DMS) is a derivative-free optimization class of algorithms, suited for computing approximations to the complete Pareto front of a given multiobjective optimization problem. In DMS class, constraints are addressed with an extreme barrier approach, only evaluating feasible points. It has a well-supported convergence analysis and simple implementations present a good numerical performance, both in academic test sets and in real applications. Recently, this numerical performance was improved with the definition of a search step based on the minimization of quadratic polynomial models, corresponding to the algorithm BoostDMS. In this work, we propose and numerically evaluate strategies to improve the performance of BoostDMS, mainly through parallelization applied to the search and to the poll steps. The final parallelized version not only considerably decreases the computational time required for solving a multiobjective optimization problem, but also increases the quality of the computed approximation to the Pareto front. Extensive numerical results will be reported in an academic test set and in a chemical engineering application.preprintpublishe
Ocular neuromyotonia
Ocular neuromyotonia is a rare, albeit treatable, ocular motor disorder, characterised by recurrent brief episodes of diplopia due to tonic extraocular muscle contraction. Ephaptic transmission in a chronically damaged ocular motor nerve is the possible underlying mechanism. It usually improves with carbamazepine. A 53-year-old woman presented with a 4-month history of recurrent episodes of binocular vertical diplopia (up to 40/day), either spontaneously or after sustained downward gaze. Between episodes she had a mild left fourth nerve palsy. Sustained downward gaze consistently triggered downward left eye tonic deviation, lasting around 1 min. MR scan of the brain was normal. She improved on starting carbamazepine but developed a rash that necessitated stopping the drug. Switching to lacosamide controlled her symptoms.info:eu-repo/semantics/publishedVersio
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