Conjunto para habitação social com princípios bioclimáticos para o município de Governador Valadares, MG

Este artigo apresenta a aplicação de conceitos da arquitetura bioclimática em um projeto para habitação social concebido para o município de Governador Valadares-MG, para o qual foram propostas tipologias distintas de habitação e áreas de uso comum. Objetiva incentivar a promoção de projetos mais racionais do ponto de vista energético, os quais sejam economicamente viáveis em longo prazo, confortáveis para seus habitantes e adequados ambientalmente. Além dos princípios bioclimáticos, foram utilizados conceitos da engenharia simultânea para direcionar as decisões de projeto de maneira simultânea e interligada. O desenho urbano e as edificações foram projetados considerando as especificadades locais como o clima quente e úmido, o relevo acidentado, e a existência de um curso d’água no terreno, dentre outros condicionantes projetuais. O ordenamento considerou os cálculos de declividade do terreno, das densidades populacionais e da proporção entre a área construída, livre e arborizada. Também foram respeitadas as normas de circulação e de acessibilidade urbana. Na fase de pré-projeto, o uso das tabelas de Mahoney foi fundamental para determinar as principais diretrizes climáticas do desenho urbano e das edificações.  A declividade do terreno natural foi avaliada a partir de um programa computacional – ArcMap, que gerou mapas temáticos. A execução de maquete física do terreno auxiliou também nos estudos de ventilação e insolação, realizados, respectivamente, em túnel de ventos e heliodon. As necessidades sociais foram respeitadas baseando-se em um levantamento do padrão familiar e social da cidade. Além disso, os materiais e as técnicas construtivas foram escolhidos conforme as características locais. De uma área total de 5 hectare, 64% foi parcelada em lotes; o restante foi destinado ao sistema de circulação, à implantação de equipamentos comunitários e aos espaços livres. Foram propostas quatro tipologias distintas de habitações

Phase Diagram of the Electron-Doped Cuprate Superconductors

We investigate the phase diagram of the electron-doped systems in high-Tc cuprates. We calculate the superconducting transition temperature Tc, the antiferromagnetic transition temperature TN, the NMR relaxation rate 1/T1 with the antiferromagnetic fluctuations in the fluctuation-exchange (FLEX) approximation and with the superconducting fluctuations in the self-consistent t-matrix approximation. Obtained phase diagram has common features as those in the hole-doped systems, including the antiferromagnetic state, the superconducting state and the spin gap phenomenon. Doping-dependences of TN, Tc and Tsg (spin gap temperature) are, however, different with those in the hole-doped systems. These differences are due to the intrinsic nature of the ingap states which are intimately related with the Zhang-Rice singlets in the hole-doped systems and are correlated d-electrons in the electron-doped systems, respectively, which has been shown in the d-p model.Comment: 4 pages, 3 figure

Anomalous Transport Phenomena in Fermi Liquids with Strong Magnetic Fluctuations

In many strongly correlated electron systems, remarkable violation of the relaxation time approximation (RTA) is observed. The most famous example would be high-Tc superconductors (HTSCs), and similar anomalous transport phenomena have been observed in metals near their antiferromagnetic (AF) quantum critical point (QCP). Here, we develop a transport theory involving resistivity and Hall coefficient on the basis of the microscopic Fermi liquid theory, by considering the current vertex correction (CVC). In nearly AF Fermi liquids, the CVC accounts for the significant enhancements in the Hall coefficient, magnetoresistance, thermoelectric power, and Nernst coefficient in nearly AF metals. According to the numerical study, aspects of anomalous transport phenomena in HTSC are explained in a unified way by considering the CVC, without introducing any fitting parameters; this strongly supports the idea that HTSCs are Fermi liquids with strong AF fluctuations. In addition, the striking \omega-dependence of the AC Hall coefficient and the remarkable effects of impurities on the transport coefficients in HTSCs appear to fit naturally into the present theory. The present theory also explains very similar anomalous transport phenomena occurring in CeCoIn5 and CeRhIn5, which is a heavy-fermion system near the AF QCP, and in the organic superconductor \kappa-(BEDT-TTF).Comment: 100 pages, Rep. Prog. Phys. 71, 026501 (2008

Critical temperature of an anisotropic superconductor containing both nonmagnetic and magnetic impurities

The combined effect of both nonmagnetic and magnetic impurities on the superconducting transition temperature is studied theoretically within the BCS model. An expression for the critical temperature as a function of potential and spin-flip scattering rates is derived for a two-dimensional superconductor with arbitrary in-plane anisotropy of the superconducting order parameter, ranging from isotropic s-wave to d-wave (or any pairing state with nonzero angular momentum) and including anisotropic s-wave and mixed (d+s)-wave as particular cases. This expression generalizes the well-known Abrikosov-Gor'kov formula for the critical temperature of impure superconductors. The effect of defects and impurities in high temperature superconductors is discussed.Comment: 4 eps figure

Percepção sonora e conforto acústico em espaços urbanos do município de Belo Horizonte, MG

Resumo O presente artigo tem como objetivo apresentar e analisar as respostas dos usuários de espaços urbanos abertos com relação à percepção do volume sonoro e à avaliação de conforto acústico, com base em dados coletados em campo durante o ano de 2013, em duas praças do município de Belo Horizonte, MG. Durante os levantamentos, dados acústicos foram medidos simultaneamente à aplicação de questionários, utilizados para coleta de variáveis subjetivas e individuais. O LAeq,T foi o índice utilizado para caracterização dos ambientes sonoros. Os resultados demonstram que, sob as mesmas condições acústicas, tanto no que diz respeito à percepção do volume sonoro quanto à avaliação de conforto acústico, os indivíduos tendem a ser mais tolerantes na praça que possui a melhor ambiência e as melhores condições de conforto térmico. As faixas de percepção do volume sonoro definidas neste estudo foram: Baixo, LAeq < 35 dB(A); Normal, 36 < LAeq < 67 dB(A); Alto, LAeq > 68 dB(A). Com relação à avaliação do conforto acústico, as faixas definidas foram: Confortável, LAeq < 67 dB(A); e Desconfortável, LAeq > 68 dB(A). Espera-se que esses resultados contribuam para um maior entendimento das questões relativas ao conforto acústico urbano

Amplification of telomerase (hTERT) gene is a poor prognostic marker in non-small-cell lung cancer

Telomerase reactivation is a hallmark of human carcinogenesis. Increased telomerase activity may result from gene amplification and/or overexpression. This study evaluates the prognostic value of hTERT gene amplification and mRNA overexpression in 144 resectable non-small-cell lung cancer (NSCLC) specimens. The hTERT gene copy number was assessed by quantitative polymerase chain reaction (qPCR) on laser-capture microdissected tumour cells of 81 tumours, and by fluorescence in situ hybridisation (FISH) on a subset of 59 tumours. hTERT mRNA level was determined by reverse transcription (RT)–qPCR in 130 tumours. In total, 57% of (46 out of 81) primary NSCLC specimens demonstrated hTERT amplification, which was significantly more common (P<0.001) in adenocarcinoma (30 out of 40) than in squamous cell carcinoma (13 out of 37). The hTERT mRNA overexpression was noted in 74% (94 out of 130) of tumours; it was more frequent in squamous cell than in adenocarcinoma (87 vs 68%, P=0.03). Overexpression was significantly associated with amplification (P=0.03), especially in adenocarcinoma. The hTERT gene amplification was prognostic for shorter recurrence-free survival (hazard ratio=2.16, P=0.03). These data indicate that gene amplification is an important mechanism for hTERT overexpression in lung adenocarcinoma and is an independent poor prognostic marker for disease-free survival in NSCLC

Evaluation of Spin-Triplet Superconductivity in Sr2RuO4

This review presents a summary and evaluations of the superconducting properties of the layered ruthenate Sr2RuO4 as they are known in the autumn of 2011. This paper appends the main progress that has been made since the preceding review by Mackenzie and Maeno was published in 2003. Here, special focus is placed on the critical evaluation of the spin-triplet, odd-parity pairing scenario applied to Sr2RuO4. After an introduction to superconductors with possible odd-parity pairing, accumulated evidence for the pairing symmetry of Sr2RuO4 is examined. Then, significant recent progress on the theoretical approaches to the superconducting pairing by Coulomb repulsion is reviewed. A section is devoted to some experimental properties of Sr2RuO4 that seem to defy simple explanations in terms of currently available spin-triplet scenario. The next section deals with some new developments using eutectic boundaries and micro-crystals, which reveals novel superconducting phenomena related to chiral edge states, odd-frequency pairing states, and half-fluxoid states. Some of these properties are intimately connected with the properties as a topological superconductor. The article concludes with a summary of knowledge emerged from the study of Sr2RuO4 that are now more widely applied to understand the physics of other unconventional superconductors, as well as with a brief discussion of relatively unexplored but promising areas of ongoing and future studies of Sr2RuO4.Comment: 31 pages, 35 figures, published in J. Phys. Soc. Jpn. as a review article of Special Topic

A Defined, Feeder-Free, Serum-Free System to Generate In Vitro Hematopoietic Progenitors and Differentiated Blood Cells from hESCs and hiPSCs

Human ESC and iPSC are an attractive source of cells of high quantity and purity to be used to elucidate early human development processes, for drug discovery, and in clinical cell therapy applications. To efficiently differentiate pluripotent cells into a pure population of hematopoietic progenitors we have developed a new 2-dimentional, defined and highly efficient protocol that avoids the use of feeder cells, serum or embryoid body formation. Here we showed that a single matrix protein in combination with growth factors and a hypoxic environment is sufficient to generate from pluripotent cells hematopoietic progenitors capable of differentiating further in mature cell types of different lineages of the blood system. We tested the differentiation method using hESCs and 9 iPSC lines generated from different tissues. These data indicate the robustness of the protocol providing a valuable tool for the generation of clinical-grade hematopoietic cells from pluripotent cells