A utilização sustentável das malhas estruturais de madeira

As malhas estruturais de madeira são estruturas com características muito particulares que lhe conferem a sustentabilidade que hoje em dia se procura na construção. Contudo, a sua utilização tem que ser analisada considerando essas características ímpares que lhe podem conferir uma ajustada utilização, ou não, tendo em conta o contexto em que se insere e o desenho da própria malha. Nesse sentido, é necessário compreender estas malhas como um todo. Desde o seu enorme potencial formal e espacial até às suas limitações geométricas, físicas e construtivas. Apenas com uma base informada se pode, sequer, esboçar a sua adequada utilização. Neste trabalho, com base num caso de estudo, vai tentar-se perceber a adequação de uma malha estrutural de madeira. Uma utilização completa ou parcial compreendendo as ditas limitações da solução e negociando as qualidades de cada opção.Este trabalho é financiado pela FEDER através do Programa Operacional de Fatores Competitivos - COMPETE e por fundos nacionais através da FCT - Fundação para Ciência e Tecnologia no âmbito do projeto POCI-01-0145-FEDER-007633. Agradece-se o apoio da Fundação para a Ciência e Tecnologia (FCT) através da bolsa de doutorado SFRH / BD / 104677/2014.info:eu-repo/semantics/publishedVersio

Tectonic design of elastic timber gridshells

This paper aims to 'bridge the gap' between engineers and architects for a better understanding of the design process of elastic timber gridshells. The purpose is to inspire architects to develop innovative timber structural forms informed by engineering knowledge. This paper is organised in two parts: the first part is a theoretical reflection on the concept of tectonic and on the combined application of architectural and structural knowledge; the second part is dedicated to the review and definition of the various decisions and consequences during the design and construction of elastic timber gridshells.This work is financed by FEDER funds through the Competitively Factors Operational Programme - COMPETE and by national funds through FCT –Foundation for Science and Technology within the scope of the project POCI-01-0145-FEDER-007633. The support of the Foundation for Science and Technology (FCT) through doctoral fellowship SFRH/BD/104677/2014 is grateful. The support of the Aarhus University through the financial support for participation in this conference

Experimental Demonstration of a Structured Material with Extreme Effective Parameters at Microwaves

Following our recent theoretical studies [M. G. Silveirinha, C. A. Fernandes, Phys. Rev. B, 78, 033108, 2008], it is experimentally verified that an array of crossed metallic wires may behave as a nonresonant material with extremely large index of refraction at microwaves, and may enable the realization of ultra-subwavelength waveguides.Comment: accepted for publication in Applied Physics Letters (in press). Applied Physics Letters (in press) (2008

ADENOPATIA CERVICAL COMO MANIFESTAÇÃO DE CANCRO DO CÓLON

Introduction: Colorectal cancer is one of the most frequent cancers worldwide, being the third most common cancer diagnosed and corresponding to the second cause of death by cancer. Approximately 25% of patients have already disseminated disease at the time of diagnosis. Case Report: We present the case of a 68-year-old female patient presented with complaints of cervical mass. She was then submitted to a biopsy of the cervical adenopathy that revealed metastatic adenocarcinoma tissue with probable gastrointestinal origin. A work-up was performed and revealed a sigmoid colon adenocarcinoma. Due to associated morbidities she was submitted to supportive treatment. Discussion: This case demonstrates the singularity of metastatic pattern in colon carcinoma. The mechanism of distant lymph node metastases in colorectal cancer still remains uncertain, nevertheless this represents an advanced stage of the disease that bears a poor prognosis. Conclusion: Few reports in the literature showed a good outcome with primary tumor excision and adjuvant chemotherapy but this decision should be discussed in a multidisciplinary team in order to decide the best treatment option for each patient.Introdução: O cancro colorectal é um dos cancros mais frequentes a nível mundial, sendo o terceiro cancro mais frequentemente diagnosticado e corresponde à segunda causa de morte por cancro. Cerca de 25% dos doentes apresentam doença disseminada à data de diagnóstico. Caso Clínico: Os autores apresentam o caso de uma doente de 68 anos, do sexo feminino, que se apresentou com queixas de uma tumefacção cervical. Foi posteriormente submetida a biópsia excisional que revelou a presença de metástase de adenocarcinoma provavelmente intestinal. Foi realizado o estudo complementar com identificação de um adenocarcinoma do cólon sigmoide. Devido às morbilidades associadas foi oferecido tratamento de suporte. Discussão: Este caso representa a singularidade do padrão de metastização do cancro do cólon. O mecanismo de metastização ganglionar à distância não se encontra totalmente esclarecido, no entanto, representa um estadio de doença avançado com um mau prognóstico associado. Conclusão: Alguns casos na literatura demonstraram bons resultados com a excisão do tumor primário seguida de quimioterapia adjuvante, esta decisão deve ser realizada por uma equipa multidisciplinar de forma a avaliar a melhor opção terapêutica para cada doente

Exploring the Small Mass Limit of Stationary Black Holes in Theories with Gauss-Bonnet Terms

In this work we examine the small mass limit of black holes, with and without spin, in theories with a scalar field non-minimally coupled to a Gauss-Bonnet term. First, we provide an analytical example for a theory where a static closed-form solution with a small mass limit is known, and later use analytical and numerical techniques to explore this limit in standard scalar-Gauss-Bonnet theories with dilatonic, linear and quadratic couplings. In most cases, we find an inner singularity that overlaps with the event horizon of the static black hole as the small mass limit is reached. Moreover, since solutions in this limit possess a non-vanishing Hawking temperature, a naked singularity is expected to be reached through evaporation, raising questions concerning the consistency of these theories altogether. On the other hand, we provide for the first time an example of a coupling where the small mass limit is never reached, thus preferred from the point of view of cosmic censorship. Finally, we consider black holes with spin and numerically investigate how this changes the picture, using these to place the tightest upper bounds to date on the coupling constant for the dilatonic and linear theories, with $\sqrt{\overline{\alpha}} < 1$ km.Comment: 18 pages, 8 figure

Magneto-mechanically induced antimicrobial properties of cone-like shaped surfaces

Hygienic surfaces that prevent the proliferation of harmful microorganisms are required in a large variety of environments, including medical areas. Novel strategies are being developed to impede microorganisms colonization of surfaces. In this work, Terfenol-D cone-like shaped nanopatterned surfaces are fabricated by sputtering. The bactericidal effect of such surfaces owed to their morphology is increased in combination with an alternating magnetic field, which boosts the mechanical injury caused to the planktonic cells. Bactericidal assays with Gram-negative Escherichia coli are carried out under static (i.e. without any external stimuli) and dynamic (under the application of an alternating magnetic field) conditions for control silicon substrates, Terfenol-D films and nanostructured surfaces. The nanostructured surfaces at the dynamic condition exhibit the larger bactericidal effect. Bacterial adhesion on the materials was analyzed, and results show a reduction of the attachment surface of bacterial cells on Terfenol-D surfaces in comparison with the control silicon that are attributed both to material properties and nanostructuration. Thus, this work exhibits a method to induce and/or improve the mechanical antimicrobial behavior of surfaces via application of a magnetic field, as an alternative or in combination with chemical methods, which are losing effectiveness due to the increase of antibiotic resistance.FCT -Fundação para a Ciência e a Tecnologia(P2018/NMT-4321)info:eu-repo/semantics/publishedVersio